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[linux.git] / security / selinux / hooks.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Security-Enhanced Linux (SELinux) security module
4  *
5  *  This file contains the SELinux hook function implementations.
6  *
7  *  Authors:  Stephen Smalley, <[email protected]>
8  *            Chris Vance, <[email protected]>
9  *            Wayne Salamon, <[email protected]>
10  *            James Morris <[email protected]>
11  *
12  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
13  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <[email protected]>
14  *                                         Eric Paris <[email protected]>
15  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
16  *                          <[email protected]>
17  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
18  *      Paul Moore <[email protected]>
19  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
20  *                     Yuichi Nakamura <[email protected]>
21  *  Copyright (C) 2016 Mellanox Technologies
22  */
23
24 #include <linux/init.h>
25 #include <linux/kd.h>
26 #include <linux/kernel.h>
27 #include <linux/kernel_read_file.h>
28 #include <linux/errno.h>
29 #include <linux/sched/signal.h>
30 #include <linux/sched/task.h>
31 #include <linux/lsm_hooks.h>
32 #include <linux/xattr.h>
33 #include <linux/capability.h>
34 #include <linux/unistd.h>
35 #include <linux/mm.h>
36 #include <linux/mman.h>
37 #include <linux/slab.h>
38 #include <linux/pagemap.h>
39 #include <linux/proc_fs.h>
40 #include <linux/swap.h>
41 #include <linux/spinlock.h>
42 #include <linux/syscalls.h>
43 #include <linux/dcache.h>
44 #include <linux/file.h>
45 #include <linux/fdtable.h>
46 #include <linux/namei.h>
47 #include <linux/mount.h>
48 #include <linux/fs_context.h>
49 #include <linux/fs_parser.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h>             /* for local_port_range[] */
55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
56 #include <net/inet_connection_sock.h>
57 #include <net/net_namespace.h>
58 #include <net/netlabel.h>
59 #include <linux/uaccess.h>
60 #include <asm/ioctls.h>
61 #include <linux/atomic.h>
62 #include <linux/bitops.h>
63 #include <linux/interrupt.h>
64 #include <linux/netdevice.h>    /* for network interface checks */
65 #include <net/netlink.h>
66 #include <linux/tcp.h>
67 #include <linux/udp.h>
68 #include <linux/dccp.h>
69 #include <linux/sctp.h>
70 #include <net/sctp/structs.h>
71 #include <linux/quota.h>
72 #include <linux/un.h>           /* for Unix socket types */
73 #include <net/af_unix.h>        /* for Unix socket types */
74 #include <linux/parser.h>
75 #include <linux/nfs_mount.h>
76 #include <net/ipv6.h>
77 #include <linux/hugetlb.h>
78 #include <linux/personality.h>
79 #include <linux/audit.h>
80 #include <linux/string.h>
81 #include <linux/mutex.h>
82 #include <linux/posix-timers.h>
83 #include <linux/syslog.h>
84 #include <linux/user_namespace.h>
85 #include <linux/export.h>
86 #include <linux/msg.h>
87 #include <linux/shm.h>
88 #include <uapi/linux/shm.h>
89 #include <linux/bpf.h>
90 #include <linux/kernfs.h>
91 #include <linux/stringhash.h>   /* for hashlen_string() */
92 #include <uapi/linux/mount.h>
93 #include <linux/fsnotify.h>
94 #include <linux/fanotify.h>
95 #include <linux/io_uring/cmd.h>
96 #include <uapi/linux/lsm.h>
97
98 #include "avc.h"
99 #include "objsec.h"
100 #include "netif.h"
101 #include "netnode.h"
102 #include "netport.h"
103 #include "ibpkey.h"
104 #include "xfrm.h"
105 #include "netlabel.h"
106 #include "audit.h"
107 #include "avc_ss.h"
108
109 #define SELINUX_INODE_INIT_XATTRS 1
110
111 struct selinux_state selinux_state;
112
113 /* SECMARK reference count */
114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
115
116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
117 static int selinux_enforcing_boot __initdata;
118
119 static int __init enforcing_setup(char *str)
120 {
121         unsigned long enforcing;
122         if (!kstrtoul(str, 0, &enforcing))
123                 selinux_enforcing_boot = enforcing ? 1 : 0;
124         return 1;
125 }
126 __setup("enforcing=", enforcing_setup);
127 #else
128 #define selinux_enforcing_boot 1
129 #endif
130
131 int selinux_enabled_boot __initdata = 1;
132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
133 static int __init selinux_enabled_setup(char *str)
134 {
135         unsigned long enabled;
136         if (!kstrtoul(str, 0, &enabled))
137                 selinux_enabled_boot = enabled ? 1 : 0;
138         return 1;
139 }
140 __setup("selinux=", selinux_enabled_setup);
141 #endif
142
143 static int __init checkreqprot_setup(char *str)
144 {
145         unsigned long checkreqprot;
146
147         if (!kstrtoul(str, 0, &checkreqprot)) {
148                 if (checkreqprot)
149                         pr_err("SELinux: checkreqprot set to 1 via kernel parameter.  This is no longer supported.\n");
150         }
151         return 1;
152 }
153 __setup("checkreqprot=", checkreqprot_setup);
154
155 /**
156  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
157  *
158  * Description:
159  * This function checks the SECMARK reference counter to see if any SECMARK
160  * targets are currently configured, if the reference counter is greater than
161  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
162  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
163  * policy capability is enabled, SECMARK is always considered enabled.
164  *
165  */
166 static int selinux_secmark_enabled(void)
167 {
168         return (selinux_policycap_alwaysnetwork() ||
169                 atomic_read(&selinux_secmark_refcount));
170 }
171
172 /**
173  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
174  *
175  * Description:
176  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
177  * (1) if any are enabled or false (0) if neither are enabled.  If the
178  * always_check_network policy capability is enabled, peer labeling
179  * is always considered enabled.
180  *
181  */
182 static int selinux_peerlbl_enabled(void)
183 {
184         return (selinux_policycap_alwaysnetwork() ||
185                 netlbl_enabled() || selinux_xfrm_enabled());
186 }
187
188 static int selinux_netcache_avc_callback(u32 event)
189 {
190         if (event == AVC_CALLBACK_RESET) {
191                 sel_netif_flush();
192                 sel_netnode_flush();
193                 sel_netport_flush();
194                 synchronize_net();
195         }
196         return 0;
197 }
198
199 static int selinux_lsm_notifier_avc_callback(u32 event)
200 {
201         if (event == AVC_CALLBACK_RESET) {
202                 sel_ib_pkey_flush();
203                 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
204         }
205
206         return 0;
207 }
208
209 /*
210  * initialise the security for the init task
211  */
212 static void cred_init_security(void)
213 {
214         struct task_security_struct *tsec;
215
216         tsec = selinux_cred(unrcu_pointer(current->real_cred));
217         tsec->osid = tsec->sid = SECINITSID_KERNEL;
218 }
219
220 /*
221  * get the security ID of a set of credentials
222  */
223 static inline u32 cred_sid(const struct cred *cred)
224 {
225         const struct task_security_struct *tsec;
226
227         tsec = selinux_cred(cred);
228         return tsec->sid;
229 }
230
231 static void __ad_net_init(struct common_audit_data *ad,
232                           struct lsm_network_audit *net,
233                           int ifindex, struct sock *sk, u16 family)
234 {
235         ad->type = LSM_AUDIT_DATA_NET;
236         ad->u.net = net;
237         net->netif = ifindex;
238         net->sk = sk;
239         net->family = family;
240 }
241
242 static void ad_net_init_from_sk(struct common_audit_data *ad,
243                                 struct lsm_network_audit *net,
244                                 struct sock *sk)
245 {
246         __ad_net_init(ad, net, 0, sk, 0);
247 }
248
249 static void ad_net_init_from_iif(struct common_audit_data *ad,
250                                  struct lsm_network_audit *net,
251                                  int ifindex, u16 family)
252 {
253         __ad_net_init(ad, net, ifindex, NULL, family);
254 }
255
256 /*
257  * get the objective security ID of a task
258  */
259 static inline u32 task_sid_obj(const struct task_struct *task)
260 {
261         u32 sid;
262
263         rcu_read_lock();
264         sid = cred_sid(__task_cred(task));
265         rcu_read_unlock();
266         return sid;
267 }
268
269 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
270
271 /*
272  * Try reloading inode security labels that have been marked as invalid.  The
273  * @may_sleep parameter indicates when sleeping and thus reloading labels is
274  * allowed; when set to false, returns -ECHILD when the label is
275  * invalid.  The @dentry parameter should be set to a dentry of the inode.
276  */
277 static int __inode_security_revalidate(struct inode *inode,
278                                        struct dentry *dentry,
279                                        bool may_sleep)
280 {
281         struct inode_security_struct *isec = selinux_inode(inode);
282
283         might_sleep_if(may_sleep);
284
285         /*
286          * The check of isec->initialized below is racy but
287          * inode_doinit_with_dentry() will recheck with
288          * isec->lock held.
289          */
290         if (selinux_initialized() &&
291             data_race(isec->initialized != LABEL_INITIALIZED)) {
292                 if (!may_sleep)
293                         return -ECHILD;
294
295                 /*
296                  * Try reloading the inode security label.  This will fail if
297                  * @opt_dentry is NULL and no dentry for this inode can be
298                  * found; in that case, continue using the old label.
299                  */
300                 inode_doinit_with_dentry(inode, dentry);
301         }
302         return 0;
303 }
304
305 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
306 {
307         return selinux_inode(inode);
308 }
309
310 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
311 {
312         int error;
313
314         error = __inode_security_revalidate(inode, NULL, !rcu);
315         if (error)
316                 return ERR_PTR(error);
317         return selinux_inode(inode);
318 }
319
320 /*
321  * Get the security label of an inode.
322  */
323 static struct inode_security_struct *inode_security(struct inode *inode)
324 {
325         __inode_security_revalidate(inode, NULL, true);
326         return selinux_inode(inode);
327 }
328
329 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
330 {
331         struct inode *inode = d_backing_inode(dentry);
332
333         return selinux_inode(inode);
334 }
335
336 /*
337  * Get the security label of a dentry's backing inode.
338  */
339 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
340 {
341         struct inode *inode = d_backing_inode(dentry);
342
343         __inode_security_revalidate(inode, dentry, true);
344         return selinux_inode(inode);
345 }
346
347 static void inode_free_security(struct inode *inode)
348 {
349         struct inode_security_struct *isec = selinux_inode(inode);
350         struct superblock_security_struct *sbsec;
351
352         if (!isec)
353                 return;
354         sbsec = selinux_superblock(inode->i_sb);
355         /*
356          * As not all inode security structures are in a list, we check for
357          * empty list outside of the lock to make sure that we won't waste
358          * time taking a lock doing nothing.
359          *
360          * The list_del_init() function can be safely called more than once.
361          * It should not be possible for this function to be called with
362          * concurrent list_add(), but for better safety against future changes
363          * in the code, we use list_empty_careful() here.
364          */
365         if (!list_empty_careful(&isec->list)) {
366                 spin_lock(&sbsec->isec_lock);
367                 list_del_init(&isec->list);
368                 spin_unlock(&sbsec->isec_lock);
369         }
370 }
371
372 struct selinux_mnt_opts {
373         u32 fscontext_sid;
374         u32 context_sid;
375         u32 rootcontext_sid;
376         u32 defcontext_sid;
377 };
378
379 static void selinux_free_mnt_opts(void *mnt_opts)
380 {
381         kfree(mnt_opts);
382 }
383
384 enum {
385         Opt_error = -1,
386         Opt_context = 0,
387         Opt_defcontext = 1,
388         Opt_fscontext = 2,
389         Opt_rootcontext = 3,
390         Opt_seclabel = 4,
391 };
392
393 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
394 static const struct {
395         const char *name;
396         int len;
397         int opt;
398         bool has_arg;
399 } tokens[] = {
400         A(context, true),
401         A(fscontext, true),
402         A(defcontext, true),
403         A(rootcontext, true),
404         A(seclabel, false),
405 };
406 #undef A
407
408 static int match_opt_prefix(char *s, int l, char **arg)
409 {
410         unsigned int i;
411
412         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
413                 size_t len = tokens[i].len;
414                 if (len > l || memcmp(s, tokens[i].name, len))
415                         continue;
416                 if (tokens[i].has_arg) {
417                         if (len == l || s[len] != '=')
418                                 continue;
419                         *arg = s + len + 1;
420                 } else if (len != l)
421                         continue;
422                 return tokens[i].opt;
423         }
424         return Opt_error;
425 }
426
427 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
428
429 static int may_context_mount_sb_relabel(u32 sid,
430                         struct superblock_security_struct *sbsec,
431                         const struct cred *cred)
432 {
433         const struct task_security_struct *tsec = selinux_cred(cred);
434         int rc;
435
436         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
437                           FILESYSTEM__RELABELFROM, NULL);
438         if (rc)
439                 return rc;
440
441         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
442                           FILESYSTEM__RELABELTO, NULL);
443         return rc;
444 }
445
446 static int may_context_mount_inode_relabel(u32 sid,
447                         struct superblock_security_struct *sbsec,
448                         const struct cred *cred)
449 {
450         const struct task_security_struct *tsec = selinux_cred(cred);
451         int rc;
452         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
453                           FILESYSTEM__RELABELFROM, NULL);
454         if (rc)
455                 return rc;
456
457         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
458                           FILESYSTEM__ASSOCIATE, NULL);
459         return rc;
460 }
461
462 static int selinux_is_genfs_special_handling(struct super_block *sb)
463 {
464         /* Special handling. Genfs but also in-core setxattr handler */
465         return  !strcmp(sb->s_type->name, "sysfs") ||
466                 !strcmp(sb->s_type->name, "pstore") ||
467                 !strcmp(sb->s_type->name, "debugfs") ||
468                 !strcmp(sb->s_type->name, "tracefs") ||
469                 !strcmp(sb->s_type->name, "rootfs") ||
470                 (selinux_policycap_cgroupseclabel() &&
471                  (!strcmp(sb->s_type->name, "cgroup") ||
472                   !strcmp(sb->s_type->name, "cgroup2")));
473 }
474
475 static int selinux_is_sblabel_mnt(struct super_block *sb)
476 {
477         struct superblock_security_struct *sbsec = selinux_superblock(sb);
478
479         /*
480          * IMPORTANT: Double-check logic in this function when adding a new
481          * SECURITY_FS_USE_* definition!
482          */
483         BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
484
485         switch (sbsec->behavior) {
486         case SECURITY_FS_USE_XATTR:
487         case SECURITY_FS_USE_TRANS:
488         case SECURITY_FS_USE_TASK:
489         case SECURITY_FS_USE_NATIVE:
490                 return 1;
491
492         case SECURITY_FS_USE_GENFS:
493                 return selinux_is_genfs_special_handling(sb);
494
495         /* Never allow relabeling on context mounts */
496         case SECURITY_FS_USE_MNTPOINT:
497         case SECURITY_FS_USE_NONE:
498         default:
499                 return 0;
500         }
501 }
502
503 static int sb_check_xattr_support(struct super_block *sb)
504 {
505         struct superblock_security_struct *sbsec = selinux_superblock(sb);
506         struct dentry *root = sb->s_root;
507         struct inode *root_inode = d_backing_inode(root);
508         u32 sid;
509         int rc;
510
511         /*
512          * Make sure that the xattr handler exists and that no
513          * error other than -ENODATA is returned by getxattr on
514          * the root directory.  -ENODATA is ok, as this may be
515          * the first boot of the SELinux kernel before we have
516          * assigned xattr values to the filesystem.
517          */
518         if (!(root_inode->i_opflags & IOP_XATTR)) {
519                 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
520                         sb->s_id, sb->s_type->name);
521                 goto fallback;
522         }
523
524         rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
525         if (rc < 0 && rc != -ENODATA) {
526                 if (rc == -EOPNOTSUPP) {
527                         pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
528                                 sb->s_id, sb->s_type->name);
529                         goto fallback;
530                 } else {
531                         pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
532                                 sb->s_id, sb->s_type->name, -rc);
533                         return rc;
534                 }
535         }
536         return 0;
537
538 fallback:
539         /* No xattr support - try to fallback to genfs if possible. */
540         rc = security_genfs_sid(sb->s_type->name, "/",
541                                 SECCLASS_DIR, &sid);
542         if (rc)
543                 return -EOPNOTSUPP;
544
545         pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
546                 sb->s_id, sb->s_type->name);
547         sbsec->behavior = SECURITY_FS_USE_GENFS;
548         sbsec->sid = sid;
549         return 0;
550 }
551
552 static int sb_finish_set_opts(struct super_block *sb)
553 {
554         struct superblock_security_struct *sbsec = selinux_superblock(sb);
555         struct dentry *root = sb->s_root;
556         struct inode *root_inode = d_backing_inode(root);
557         int rc = 0;
558
559         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
560                 rc = sb_check_xattr_support(sb);
561                 if (rc)
562                         return rc;
563         }
564
565         sbsec->flags |= SE_SBINITIALIZED;
566
567         /*
568          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
569          * leave the flag untouched because sb_clone_mnt_opts might be handing
570          * us a superblock that needs the flag to be cleared.
571          */
572         if (selinux_is_sblabel_mnt(sb))
573                 sbsec->flags |= SBLABEL_MNT;
574         else
575                 sbsec->flags &= ~SBLABEL_MNT;
576
577         /* Initialize the root inode. */
578         rc = inode_doinit_with_dentry(root_inode, root);
579
580         /* Initialize any other inodes associated with the superblock, e.g.
581            inodes created prior to initial policy load or inodes created
582            during get_sb by a pseudo filesystem that directly
583            populates itself. */
584         spin_lock(&sbsec->isec_lock);
585         while (!list_empty(&sbsec->isec_head)) {
586                 struct inode_security_struct *isec =
587                                 list_first_entry(&sbsec->isec_head,
588                                            struct inode_security_struct, list);
589                 struct inode *inode = isec->inode;
590                 list_del_init(&isec->list);
591                 spin_unlock(&sbsec->isec_lock);
592                 inode = igrab(inode);
593                 if (inode) {
594                         if (!IS_PRIVATE(inode))
595                                 inode_doinit_with_dentry(inode, NULL);
596                         iput(inode);
597                 }
598                 spin_lock(&sbsec->isec_lock);
599         }
600         spin_unlock(&sbsec->isec_lock);
601         return rc;
602 }
603
604 static int bad_option(struct superblock_security_struct *sbsec, char flag,
605                       u32 old_sid, u32 new_sid)
606 {
607         char mnt_flags = sbsec->flags & SE_MNTMASK;
608
609         /* check if the old mount command had the same options */
610         if (sbsec->flags & SE_SBINITIALIZED)
611                 if (!(sbsec->flags & flag) ||
612                     (old_sid != new_sid))
613                         return 1;
614
615         /* check if we were passed the same options twice,
616          * aka someone passed context=a,context=b
617          */
618         if (!(sbsec->flags & SE_SBINITIALIZED))
619                 if (mnt_flags & flag)
620                         return 1;
621         return 0;
622 }
623
624 /*
625  * Allow filesystems with binary mount data to explicitly set mount point
626  * labeling information.
627  */
628 static int selinux_set_mnt_opts(struct super_block *sb,
629                                 void *mnt_opts,
630                                 unsigned long kern_flags,
631                                 unsigned long *set_kern_flags)
632 {
633         const struct cred *cred = current_cred();
634         struct superblock_security_struct *sbsec = selinux_superblock(sb);
635         struct dentry *root = sb->s_root;
636         struct selinux_mnt_opts *opts = mnt_opts;
637         struct inode_security_struct *root_isec;
638         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
639         u32 defcontext_sid = 0;
640         int rc = 0;
641
642         /*
643          * Specifying internal flags without providing a place to
644          * place the results is not allowed
645          */
646         if (kern_flags && !set_kern_flags)
647                 return -EINVAL;
648
649         mutex_lock(&sbsec->lock);
650
651         if (!selinux_initialized()) {
652                 if (!opts) {
653                         /* Defer initialization until selinux_complete_init,
654                            after the initial policy is loaded and the security
655                            server is ready to handle calls. */
656                         if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
657                                 sbsec->flags |= SE_SBNATIVE;
658                                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
659                         }
660                         goto out;
661                 }
662                 rc = -EINVAL;
663                 pr_warn("SELinux: Unable to set superblock options "
664                         "before the security server is initialized\n");
665                 goto out;
666         }
667
668         /*
669          * Binary mount data FS will come through this function twice.  Once
670          * from an explicit call and once from the generic calls from the vfs.
671          * Since the generic VFS calls will not contain any security mount data
672          * we need to skip the double mount verification.
673          *
674          * This does open a hole in which we will not notice if the first
675          * mount using this sb set explicit options and a second mount using
676          * this sb does not set any security options.  (The first options
677          * will be used for both mounts)
678          */
679         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
680             && !opts)
681                 goto out;
682
683         root_isec = backing_inode_security_novalidate(root);
684
685         /*
686          * parse the mount options, check if they are valid sids.
687          * also check if someone is trying to mount the same sb more
688          * than once with different security options.
689          */
690         if (opts) {
691                 if (opts->fscontext_sid) {
692                         fscontext_sid = opts->fscontext_sid;
693                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
694                                         fscontext_sid))
695                                 goto out_double_mount;
696                         sbsec->flags |= FSCONTEXT_MNT;
697                 }
698                 if (opts->context_sid) {
699                         context_sid = opts->context_sid;
700                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
701                                         context_sid))
702                                 goto out_double_mount;
703                         sbsec->flags |= CONTEXT_MNT;
704                 }
705                 if (opts->rootcontext_sid) {
706                         rootcontext_sid = opts->rootcontext_sid;
707                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
708                                         rootcontext_sid))
709                                 goto out_double_mount;
710                         sbsec->flags |= ROOTCONTEXT_MNT;
711                 }
712                 if (opts->defcontext_sid) {
713                         defcontext_sid = opts->defcontext_sid;
714                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
715                                         defcontext_sid))
716                                 goto out_double_mount;
717                         sbsec->flags |= DEFCONTEXT_MNT;
718                 }
719         }
720
721         if (sbsec->flags & SE_SBINITIALIZED) {
722                 /* previously mounted with options, but not on this attempt? */
723                 if ((sbsec->flags & SE_MNTMASK) && !opts)
724                         goto out_double_mount;
725                 rc = 0;
726                 goto out;
727         }
728
729         if (strcmp(sb->s_type->name, "proc") == 0)
730                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
731
732         if (!strcmp(sb->s_type->name, "debugfs") ||
733             !strcmp(sb->s_type->name, "tracefs") ||
734             !strcmp(sb->s_type->name, "binder") ||
735             !strcmp(sb->s_type->name, "bpf") ||
736             !strcmp(sb->s_type->name, "pstore") ||
737             !strcmp(sb->s_type->name, "securityfs"))
738                 sbsec->flags |= SE_SBGENFS;
739
740         if (!strcmp(sb->s_type->name, "sysfs") ||
741             !strcmp(sb->s_type->name, "cgroup") ||
742             !strcmp(sb->s_type->name, "cgroup2"))
743                 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
744
745         if (!sbsec->behavior) {
746                 /*
747                  * Determine the labeling behavior to use for this
748                  * filesystem type.
749                  */
750                 rc = security_fs_use(sb);
751                 if (rc) {
752                         pr_warn("%s: security_fs_use(%s) returned %d\n",
753                                         __func__, sb->s_type->name, rc);
754                         goto out;
755                 }
756         }
757
758         /*
759          * If this is a user namespace mount and the filesystem type is not
760          * explicitly whitelisted, then no contexts are allowed on the command
761          * line and security labels must be ignored.
762          */
763         if (sb->s_user_ns != &init_user_ns &&
764             strcmp(sb->s_type->name, "tmpfs") &&
765             strcmp(sb->s_type->name, "ramfs") &&
766             strcmp(sb->s_type->name, "devpts") &&
767             strcmp(sb->s_type->name, "overlay")) {
768                 if (context_sid || fscontext_sid || rootcontext_sid ||
769                     defcontext_sid) {
770                         rc = -EACCES;
771                         goto out;
772                 }
773                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
774                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
775                         rc = security_transition_sid(current_sid(),
776                                                      current_sid(),
777                                                      SECCLASS_FILE, NULL,
778                                                      &sbsec->mntpoint_sid);
779                         if (rc)
780                                 goto out;
781                 }
782                 goto out_set_opts;
783         }
784
785         /* sets the context of the superblock for the fs being mounted. */
786         if (fscontext_sid) {
787                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
788                 if (rc)
789                         goto out;
790
791                 sbsec->sid = fscontext_sid;
792         }
793
794         /*
795          * Switch to using mount point labeling behavior.
796          * sets the label used on all file below the mountpoint, and will set
797          * the superblock context if not already set.
798          */
799         if (sbsec->flags & SE_SBNATIVE) {
800                 /*
801                  * This means we are initializing a superblock that has been
802                  * mounted before the SELinux was initialized and the
803                  * filesystem requested native labeling. We had already
804                  * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
805                  * in the original mount attempt, so now we just need to set
806                  * the SECURITY_FS_USE_NATIVE behavior.
807                  */
808                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
809         } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
810                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
811                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
812         }
813
814         if (context_sid) {
815                 if (!fscontext_sid) {
816                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
817                                                           cred);
818                         if (rc)
819                                 goto out;
820                         sbsec->sid = context_sid;
821                 } else {
822                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
823                                                              cred);
824                         if (rc)
825                                 goto out;
826                 }
827                 if (!rootcontext_sid)
828                         rootcontext_sid = context_sid;
829
830                 sbsec->mntpoint_sid = context_sid;
831                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
832         }
833
834         if (rootcontext_sid) {
835                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
836                                                      cred);
837                 if (rc)
838                         goto out;
839
840                 root_isec->sid = rootcontext_sid;
841                 root_isec->initialized = LABEL_INITIALIZED;
842         }
843
844         if (defcontext_sid) {
845                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
846                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
847                         rc = -EINVAL;
848                         pr_warn("SELinux: defcontext option is "
849                                "invalid for this filesystem type\n");
850                         goto out;
851                 }
852
853                 if (defcontext_sid != sbsec->def_sid) {
854                         rc = may_context_mount_inode_relabel(defcontext_sid,
855                                                              sbsec, cred);
856                         if (rc)
857                                 goto out;
858                 }
859
860                 sbsec->def_sid = defcontext_sid;
861         }
862
863 out_set_opts:
864         rc = sb_finish_set_opts(sb);
865 out:
866         mutex_unlock(&sbsec->lock);
867         return rc;
868 out_double_mount:
869         rc = -EINVAL;
870         pr_warn("SELinux: mount invalid.  Same superblock, different "
871                "security settings for (dev %s, type %s)\n", sb->s_id,
872                sb->s_type->name);
873         goto out;
874 }
875
876 static int selinux_cmp_sb_context(const struct super_block *oldsb,
877                                     const struct super_block *newsb)
878 {
879         struct superblock_security_struct *old = selinux_superblock(oldsb);
880         struct superblock_security_struct *new = selinux_superblock(newsb);
881         char oldflags = old->flags & SE_MNTMASK;
882         char newflags = new->flags & SE_MNTMASK;
883
884         if (oldflags != newflags)
885                 goto mismatch;
886         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
887                 goto mismatch;
888         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
889                 goto mismatch;
890         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
891                 goto mismatch;
892         if (oldflags & ROOTCONTEXT_MNT) {
893                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
894                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
895                 if (oldroot->sid != newroot->sid)
896                         goto mismatch;
897         }
898         return 0;
899 mismatch:
900         pr_warn("SELinux: mount invalid.  Same superblock, "
901                             "different security settings for (dev %s, "
902                             "type %s)\n", newsb->s_id, newsb->s_type->name);
903         return -EBUSY;
904 }
905
906 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
907                                         struct super_block *newsb,
908                                         unsigned long kern_flags,
909                                         unsigned long *set_kern_flags)
910 {
911         int rc = 0;
912         const struct superblock_security_struct *oldsbsec =
913                                                 selinux_superblock(oldsb);
914         struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
915
916         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
917         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
918         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
919
920         /*
921          * Specifying internal flags without providing a place to
922          * place the results is not allowed.
923          */
924         if (kern_flags && !set_kern_flags)
925                 return -EINVAL;
926
927         mutex_lock(&newsbsec->lock);
928
929         /*
930          * if the parent was able to be mounted it clearly had no special lsm
931          * mount options.  thus we can safely deal with this superblock later
932          */
933         if (!selinux_initialized()) {
934                 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
935                         newsbsec->flags |= SE_SBNATIVE;
936                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
937                 }
938                 goto out;
939         }
940
941         /* how can we clone if the old one wasn't set up?? */
942         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
943
944         /* if fs is reusing a sb, make sure that the contexts match */
945         if (newsbsec->flags & SE_SBINITIALIZED) {
946                 mutex_unlock(&newsbsec->lock);
947                 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
948                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
949                 return selinux_cmp_sb_context(oldsb, newsb);
950         }
951
952         newsbsec->flags = oldsbsec->flags;
953
954         newsbsec->sid = oldsbsec->sid;
955         newsbsec->def_sid = oldsbsec->def_sid;
956         newsbsec->behavior = oldsbsec->behavior;
957
958         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
959                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
960                 rc = security_fs_use(newsb);
961                 if (rc)
962                         goto out;
963         }
964
965         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
966                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
967                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
968         }
969
970         if (set_context) {
971                 u32 sid = oldsbsec->mntpoint_sid;
972
973                 if (!set_fscontext)
974                         newsbsec->sid = sid;
975                 if (!set_rootcontext) {
976                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
977                         newisec->sid = sid;
978                 }
979                 newsbsec->mntpoint_sid = sid;
980         }
981         if (set_rootcontext) {
982                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
983                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
984
985                 newisec->sid = oldisec->sid;
986         }
987
988         sb_finish_set_opts(newsb);
989 out:
990         mutex_unlock(&newsbsec->lock);
991         return rc;
992 }
993
994 /*
995  * NOTE: the caller is responsible for freeing the memory even if on error.
996  */
997 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
998 {
999         struct selinux_mnt_opts *opts = *mnt_opts;
1000         u32 *dst_sid;
1001         int rc;
1002
1003         if (token == Opt_seclabel)
1004                 /* eaten and completely ignored */
1005                 return 0;
1006         if (!s)
1007                 return -EINVAL;
1008
1009         if (!selinux_initialized()) {
1010                 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1011                 return -EINVAL;
1012         }
1013
1014         if (!opts) {
1015                 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1016                 if (!opts)
1017                         return -ENOMEM;
1018                 *mnt_opts = opts;
1019         }
1020
1021         switch (token) {
1022         case Opt_context:
1023                 if (opts->context_sid || opts->defcontext_sid)
1024                         goto err;
1025                 dst_sid = &opts->context_sid;
1026                 break;
1027         case Opt_fscontext:
1028                 if (opts->fscontext_sid)
1029                         goto err;
1030                 dst_sid = &opts->fscontext_sid;
1031                 break;
1032         case Opt_rootcontext:
1033                 if (opts->rootcontext_sid)
1034                         goto err;
1035                 dst_sid = &opts->rootcontext_sid;
1036                 break;
1037         case Opt_defcontext:
1038                 if (opts->context_sid || opts->defcontext_sid)
1039                         goto err;
1040                 dst_sid = &opts->defcontext_sid;
1041                 break;
1042         default:
1043                 WARN_ON(1);
1044                 return -EINVAL;
1045         }
1046         rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1047         if (rc)
1048                 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1049                         s, rc);
1050         return rc;
1051
1052 err:
1053         pr_warn(SEL_MOUNT_FAIL_MSG);
1054         return -EINVAL;
1055 }
1056
1057 static int show_sid(struct seq_file *m, u32 sid)
1058 {
1059         char *context = NULL;
1060         u32 len;
1061         int rc;
1062
1063         rc = security_sid_to_context(sid, &context, &len);
1064         if (!rc) {
1065                 bool has_comma = strchr(context, ',');
1066
1067                 seq_putc(m, '=');
1068                 if (has_comma)
1069                         seq_putc(m, '\"');
1070                 seq_escape(m, context, "\"\n\\");
1071                 if (has_comma)
1072                         seq_putc(m, '\"');
1073         }
1074         kfree(context);
1075         return rc;
1076 }
1077
1078 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1079 {
1080         struct superblock_security_struct *sbsec = selinux_superblock(sb);
1081         int rc;
1082
1083         if (!(sbsec->flags & SE_SBINITIALIZED))
1084                 return 0;
1085
1086         if (!selinux_initialized())
1087                 return 0;
1088
1089         if (sbsec->flags & FSCONTEXT_MNT) {
1090                 seq_putc(m, ',');
1091                 seq_puts(m, FSCONTEXT_STR);
1092                 rc = show_sid(m, sbsec->sid);
1093                 if (rc)
1094                         return rc;
1095         }
1096         if (sbsec->flags & CONTEXT_MNT) {
1097                 seq_putc(m, ',');
1098                 seq_puts(m, CONTEXT_STR);
1099                 rc = show_sid(m, sbsec->mntpoint_sid);
1100                 if (rc)
1101                         return rc;
1102         }
1103         if (sbsec->flags & DEFCONTEXT_MNT) {
1104                 seq_putc(m, ',');
1105                 seq_puts(m, DEFCONTEXT_STR);
1106                 rc = show_sid(m, sbsec->def_sid);
1107                 if (rc)
1108                         return rc;
1109         }
1110         if (sbsec->flags & ROOTCONTEXT_MNT) {
1111                 struct dentry *root = sb->s_root;
1112                 struct inode_security_struct *isec = backing_inode_security(root);
1113                 seq_putc(m, ',');
1114                 seq_puts(m, ROOTCONTEXT_STR);
1115                 rc = show_sid(m, isec->sid);
1116                 if (rc)
1117                         return rc;
1118         }
1119         if (sbsec->flags & SBLABEL_MNT) {
1120                 seq_putc(m, ',');
1121                 seq_puts(m, SECLABEL_STR);
1122         }
1123         return 0;
1124 }
1125
1126 static inline u16 inode_mode_to_security_class(umode_t mode)
1127 {
1128         switch (mode & S_IFMT) {
1129         case S_IFSOCK:
1130                 return SECCLASS_SOCK_FILE;
1131         case S_IFLNK:
1132                 return SECCLASS_LNK_FILE;
1133         case S_IFREG:
1134                 return SECCLASS_FILE;
1135         case S_IFBLK:
1136                 return SECCLASS_BLK_FILE;
1137         case S_IFDIR:
1138                 return SECCLASS_DIR;
1139         case S_IFCHR:
1140                 return SECCLASS_CHR_FILE;
1141         case S_IFIFO:
1142                 return SECCLASS_FIFO_FILE;
1143
1144         }
1145
1146         return SECCLASS_FILE;
1147 }
1148
1149 static inline int default_protocol_stream(int protocol)
1150 {
1151         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1152                 protocol == IPPROTO_MPTCP);
1153 }
1154
1155 static inline int default_protocol_dgram(int protocol)
1156 {
1157         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1158 }
1159
1160 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1161 {
1162         bool extsockclass = selinux_policycap_extsockclass();
1163
1164         switch (family) {
1165         case PF_UNIX:
1166                 switch (type) {
1167                 case SOCK_STREAM:
1168                 case SOCK_SEQPACKET:
1169                         return SECCLASS_UNIX_STREAM_SOCKET;
1170                 case SOCK_DGRAM:
1171                 case SOCK_RAW:
1172                         return SECCLASS_UNIX_DGRAM_SOCKET;
1173                 }
1174                 break;
1175         case PF_INET:
1176         case PF_INET6:
1177                 switch (type) {
1178                 case SOCK_STREAM:
1179                 case SOCK_SEQPACKET:
1180                         if (default_protocol_stream(protocol))
1181                                 return SECCLASS_TCP_SOCKET;
1182                         else if (extsockclass && protocol == IPPROTO_SCTP)
1183                                 return SECCLASS_SCTP_SOCKET;
1184                         else
1185                                 return SECCLASS_RAWIP_SOCKET;
1186                 case SOCK_DGRAM:
1187                         if (default_protocol_dgram(protocol))
1188                                 return SECCLASS_UDP_SOCKET;
1189                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1190                                                   protocol == IPPROTO_ICMPV6))
1191                                 return SECCLASS_ICMP_SOCKET;
1192                         else
1193                                 return SECCLASS_RAWIP_SOCKET;
1194                 case SOCK_DCCP:
1195                         return SECCLASS_DCCP_SOCKET;
1196                 default:
1197                         return SECCLASS_RAWIP_SOCKET;
1198                 }
1199                 break;
1200         case PF_NETLINK:
1201                 switch (protocol) {
1202                 case NETLINK_ROUTE:
1203                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1204                 case NETLINK_SOCK_DIAG:
1205                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1206                 case NETLINK_NFLOG:
1207                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1208                 case NETLINK_XFRM:
1209                         return SECCLASS_NETLINK_XFRM_SOCKET;
1210                 case NETLINK_SELINUX:
1211                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1212                 case NETLINK_ISCSI:
1213                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1214                 case NETLINK_AUDIT:
1215                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1216                 case NETLINK_FIB_LOOKUP:
1217                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1218                 case NETLINK_CONNECTOR:
1219                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1220                 case NETLINK_NETFILTER:
1221                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1222                 case NETLINK_DNRTMSG:
1223                         return SECCLASS_NETLINK_DNRT_SOCKET;
1224                 case NETLINK_KOBJECT_UEVENT:
1225                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1226                 case NETLINK_GENERIC:
1227                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1228                 case NETLINK_SCSITRANSPORT:
1229                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1230                 case NETLINK_RDMA:
1231                         return SECCLASS_NETLINK_RDMA_SOCKET;
1232                 case NETLINK_CRYPTO:
1233                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1234                 default:
1235                         return SECCLASS_NETLINK_SOCKET;
1236                 }
1237         case PF_PACKET:
1238                 return SECCLASS_PACKET_SOCKET;
1239         case PF_KEY:
1240                 return SECCLASS_KEY_SOCKET;
1241         case PF_APPLETALK:
1242                 return SECCLASS_APPLETALK_SOCKET;
1243         }
1244
1245         if (extsockclass) {
1246                 switch (family) {
1247                 case PF_AX25:
1248                         return SECCLASS_AX25_SOCKET;
1249                 case PF_IPX:
1250                         return SECCLASS_IPX_SOCKET;
1251                 case PF_NETROM:
1252                         return SECCLASS_NETROM_SOCKET;
1253                 case PF_ATMPVC:
1254                         return SECCLASS_ATMPVC_SOCKET;
1255                 case PF_X25:
1256                         return SECCLASS_X25_SOCKET;
1257                 case PF_ROSE:
1258                         return SECCLASS_ROSE_SOCKET;
1259                 case PF_DECnet:
1260                         return SECCLASS_DECNET_SOCKET;
1261                 case PF_ATMSVC:
1262                         return SECCLASS_ATMSVC_SOCKET;
1263                 case PF_RDS:
1264                         return SECCLASS_RDS_SOCKET;
1265                 case PF_IRDA:
1266                         return SECCLASS_IRDA_SOCKET;
1267                 case PF_PPPOX:
1268                         return SECCLASS_PPPOX_SOCKET;
1269                 case PF_LLC:
1270                         return SECCLASS_LLC_SOCKET;
1271                 case PF_CAN:
1272                         return SECCLASS_CAN_SOCKET;
1273                 case PF_TIPC:
1274                         return SECCLASS_TIPC_SOCKET;
1275                 case PF_BLUETOOTH:
1276                         return SECCLASS_BLUETOOTH_SOCKET;
1277                 case PF_IUCV:
1278                         return SECCLASS_IUCV_SOCKET;
1279                 case PF_RXRPC:
1280                         return SECCLASS_RXRPC_SOCKET;
1281                 case PF_ISDN:
1282                         return SECCLASS_ISDN_SOCKET;
1283                 case PF_PHONET:
1284                         return SECCLASS_PHONET_SOCKET;
1285                 case PF_IEEE802154:
1286                         return SECCLASS_IEEE802154_SOCKET;
1287                 case PF_CAIF:
1288                         return SECCLASS_CAIF_SOCKET;
1289                 case PF_ALG:
1290                         return SECCLASS_ALG_SOCKET;
1291                 case PF_NFC:
1292                         return SECCLASS_NFC_SOCKET;
1293                 case PF_VSOCK:
1294                         return SECCLASS_VSOCK_SOCKET;
1295                 case PF_KCM:
1296                         return SECCLASS_KCM_SOCKET;
1297                 case PF_QIPCRTR:
1298                         return SECCLASS_QIPCRTR_SOCKET;
1299                 case PF_SMC:
1300                         return SECCLASS_SMC_SOCKET;
1301                 case PF_XDP:
1302                         return SECCLASS_XDP_SOCKET;
1303                 case PF_MCTP:
1304                         return SECCLASS_MCTP_SOCKET;
1305 #if PF_MAX > 46
1306 #error New address family defined, please update this function.
1307 #endif
1308                 }
1309         }
1310
1311         return SECCLASS_SOCKET;
1312 }
1313
1314 static int selinux_genfs_get_sid(struct dentry *dentry,
1315                                  u16 tclass,
1316                                  u16 flags,
1317                                  u32 *sid)
1318 {
1319         int rc;
1320         struct super_block *sb = dentry->d_sb;
1321         char *buffer, *path;
1322
1323         buffer = (char *)__get_free_page(GFP_KERNEL);
1324         if (!buffer)
1325                 return -ENOMEM;
1326
1327         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1328         if (IS_ERR(path))
1329                 rc = PTR_ERR(path);
1330         else {
1331                 if (flags & SE_SBPROC) {
1332                         /* each process gets a /proc/PID/ entry. Strip off the
1333                          * PID part to get a valid selinux labeling.
1334                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1335                         while (path[1] >= '0' && path[1] <= '9') {
1336                                 path[1] = '/';
1337                                 path++;
1338                         }
1339                 }
1340                 rc = security_genfs_sid(sb->s_type->name,
1341                                         path, tclass, sid);
1342                 if (rc == -ENOENT) {
1343                         /* No match in policy, mark as unlabeled. */
1344                         *sid = SECINITSID_UNLABELED;
1345                         rc = 0;
1346                 }
1347         }
1348         free_page((unsigned long)buffer);
1349         return rc;
1350 }
1351
1352 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1353                                   u32 def_sid, u32 *sid)
1354 {
1355 #define INITCONTEXTLEN 255
1356         char *context;
1357         unsigned int len;
1358         int rc;
1359
1360         len = INITCONTEXTLEN;
1361         context = kmalloc(len + 1, GFP_NOFS);
1362         if (!context)
1363                 return -ENOMEM;
1364
1365         context[len] = '\0';
1366         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1367         if (rc == -ERANGE) {
1368                 kfree(context);
1369
1370                 /* Need a larger buffer.  Query for the right size. */
1371                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1372                 if (rc < 0)
1373                         return rc;
1374
1375                 len = rc;
1376                 context = kmalloc(len + 1, GFP_NOFS);
1377                 if (!context)
1378                         return -ENOMEM;
1379
1380                 context[len] = '\0';
1381                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1382                                     context, len);
1383         }
1384         if (rc < 0) {
1385                 kfree(context);
1386                 if (rc != -ENODATA) {
1387                         pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1388                                 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1389                         return rc;
1390                 }
1391                 *sid = def_sid;
1392                 return 0;
1393         }
1394
1395         rc = security_context_to_sid_default(context, rc, sid,
1396                                              def_sid, GFP_NOFS);
1397         if (rc) {
1398                 char *dev = inode->i_sb->s_id;
1399                 unsigned long ino = inode->i_ino;
1400
1401                 if (rc == -EINVAL) {
1402                         pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1403                                               ino, dev, context);
1404                 } else {
1405                         pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1406                                 __func__, context, -rc, dev, ino);
1407                 }
1408         }
1409         kfree(context);
1410         return 0;
1411 }
1412
1413 /* The inode's security attributes must be initialized before first use. */
1414 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1415 {
1416         struct superblock_security_struct *sbsec = NULL;
1417         struct inode_security_struct *isec = selinux_inode(inode);
1418         u32 task_sid, sid = 0;
1419         u16 sclass;
1420         struct dentry *dentry;
1421         int rc = 0;
1422
1423         if (isec->initialized == LABEL_INITIALIZED)
1424                 return 0;
1425
1426         spin_lock(&isec->lock);
1427         if (isec->initialized == LABEL_INITIALIZED)
1428                 goto out_unlock;
1429
1430         if (isec->sclass == SECCLASS_FILE)
1431                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1432
1433         sbsec = selinux_superblock(inode->i_sb);
1434         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1435                 /* Defer initialization until selinux_complete_init,
1436                    after the initial policy is loaded and the security
1437                    server is ready to handle calls. */
1438                 spin_lock(&sbsec->isec_lock);
1439                 if (list_empty(&isec->list))
1440                         list_add(&isec->list, &sbsec->isec_head);
1441                 spin_unlock(&sbsec->isec_lock);
1442                 goto out_unlock;
1443         }
1444
1445         sclass = isec->sclass;
1446         task_sid = isec->task_sid;
1447         sid = isec->sid;
1448         isec->initialized = LABEL_PENDING;
1449         spin_unlock(&isec->lock);
1450
1451         switch (sbsec->behavior) {
1452         /*
1453          * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1454          * via xattr when called from delayed_superblock_init().
1455          */
1456         case SECURITY_FS_USE_NATIVE:
1457         case SECURITY_FS_USE_XATTR:
1458                 if (!(inode->i_opflags & IOP_XATTR)) {
1459                         sid = sbsec->def_sid;
1460                         break;
1461                 }
1462                 /* Need a dentry, since the xattr API requires one.
1463                    Life would be simpler if we could just pass the inode. */
1464                 if (opt_dentry) {
1465                         /* Called from d_instantiate or d_splice_alias. */
1466                         dentry = dget(opt_dentry);
1467                 } else {
1468                         /*
1469                          * Called from selinux_complete_init, try to find a dentry.
1470                          * Some filesystems really want a connected one, so try
1471                          * that first.  We could split SECURITY_FS_USE_XATTR in
1472                          * two, depending upon that...
1473                          */
1474                         dentry = d_find_alias(inode);
1475                         if (!dentry)
1476                                 dentry = d_find_any_alias(inode);
1477                 }
1478                 if (!dentry) {
1479                         /*
1480                          * this is can be hit on boot when a file is accessed
1481                          * before the policy is loaded.  When we load policy we
1482                          * may find inodes that have no dentry on the
1483                          * sbsec->isec_head list.  No reason to complain as these
1484                          * will get fixed up the next time we go through
1485                          * inode_doinit with a dentry, before these inodes could
1486                          * be used again by userspace.
1487                          */
1488                         goto out_invalid;
1489                 }
1490
1491                 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1492                                             &sid);
1493                 dput(dentry);
1494                 if (rc)
1495                         goto out;
1496                 break;
1497         case SECURITY_FS_USE_TASK:
1498                 sid = task_sid;
1499                 break;
1500         case SECURITY_FS_USE_TRANS:
1501                 /* Default to the fs SID. */
1502                 sid = sbsec->sid;
1503
1504                 /* Try to obtain a transition SID. */
1505                 rc = security_transition_sid(task_sid, sid,
1506                                              sclass, NULL, &sid);
1507                 if (rc)
1508                         goto out;
1509                 break;
1510         case SECURITY_FS_USE_MNTPOINT:
1511                 sid = sbsec->mntpoint_sid;
1512                 break;
1513         default:
1514                 /* Default to the fs superblock SID. */
1515                 sid = sbsec->sid;
1516
1517                 if ((sbsec->flags & SE_SBGENFS) &&
1518                      (!S_ISLNK(inode->i_mode) ||
1519                       selinux_policycap_genfs_seclabel_symlinks())) {
1520                         /* We must have a dentry to determine the label on
1521                          * procfs inodes */
1522                         if (opt_dentry) {
1523                                 /* Called from d_instantiate or
1524                                  * d_splice_alias. */
1525                                 dentry = dget(opt_dentry);
1526                         } else {
1527                                 /* Called from selinux_complete_init, try to
1528                                  * find a dentry.  Some filesystems really want
1529                                  * a connected one, so try that first.
1530                                  */
1531                                 dentry = d_find_alias(inode);
1532                                 if (!dentry)
1533                                         dentry = d_find_any_alias(inode);
1534                         }
1535                         /*
1536                          * This can be hit on boot when a file is accessed
1537                          * before the policy is loaded.  When we load policy we
1538                          * may find inodes that have no dentry on the
1539                          * sbsec->isec_head list.  No reason to complain as
1540                          * these will get fixed up the next time we go through
1541                          * inode_doinit() with a dentry, before these inodes
1542                          * could be used again by userspace.
1543                          */
1544                         if (!dentry)
1545                                 goto out_invalid;
1546                         rc = selinux_genfs_get_sid(dentry, sclass,
1547                                                    sbsec->flags, &sid);
1548                         if (rc) {
1549                                 dput(dentry);
1550                                 goto out;
1551                         }
1552
1553                         if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1554                             (inode->i_opflags & IOP_XATTR)) {
1555                                 rc = inode_doinit_use_xattr(inode, dentry,
1556                                                             sid, &sid);
1557                                 if (rc) {
1558                                         dput(dentry);
1559                                         goto out;
1560                                 }
1561                         }
1562                         dput(dentry);
1563                 }
1564                 break;
1565         }
1566
1567 out:
1568         spin_lock(&isec->lock);
1569         if (isec->initialized == LABEL_PENDING) {
1570                 if (rc) {
1571                         isec->initialized = LABEL_INVALID;
1572                         goto out_unlock;
1573                 }
1574                 isec->initialized = LABEL_INITIALIZED;
1575                 isec->sid = sid;
1576         }
1577
1578 out_unlock:
1579         spin_unlock(&isec->lock);
1580         return rc;
1581
1582 out_invalid:
1583         spin_lock(&isec->lock);
1584         if (isec->initialized == LABEL_PENDING) {
1585                 isec->initialized = LABEL_INVALID;
1586                 isec->sid = sid;
1587         }
1588         spin_unlock(&isec->lock);
1589         return 0;
1590 }
1591
1592 /* Convert a Linux signal to an access vector. */
1593 static inline u32 signal_to_av(int sig)
1594 {
1595         u32 perm = 0;
1596
1597         switch (sig) {
1598         case SIGCHLD:
1599                 /* Commonly granted from child to parent. */
1600                 perm = PROCESS__SIGCHLD;
1601                 break;
1602         case SIGKILL:
1603                 /* Cannot be caught or ignored */
1604                 perm = PROCESS__SIGKILL;
1605                 break;
1606         case SIGSTOP:
1607                 /* Cannot be caught or ignored */
1608                 perm = PROCESS__SIGSTOP;
1609                 break;
1610         default:
1611                 /* All other signals. */
1612                 perm = PROCESS__SIGNAL;
1613                 break;
1614         }
1615
1616         return perm;
1617 }
1618
1619 #if CAP_LAST_CAP > 63
1620 #error Fix SELinux to handle capabilities > 63.
1621 #endif
1622
1623 /* Check whether a task is allowed to use a capability. */
1624 static int cred_has_capability(const struct cred *cred,
1625                                int cap, unsigned int opts, bool initns)
1626 {
1627         struct common_audit_data ad;
1628         struct av_decision avd;
1629         u16 sclass;
1630         u32 sid = cred_sid(cred);
1631         u32 av = CAP_TO_MASK(cap);
1632         int rc;
1633
1634         ad.type = LSM_AUDIT_DATA_CAP;
1635         ad.u.cap = cap;
1636
1637         switch (CAP_TO_INDEX(cap)) {
1638         case 0:
1639                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1640                 break;
1641         case 1:
1642                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1643                 break;
1644         default:
1645                 pr_err("SELinux:  out of range capability %d\n", cap);
1646                 BUG();
1647                 return -EINVAL;
1648         }
1649
1650         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1651         if (!(opts & CAP_OPT_NOAUDIT)) {
1652                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1653                 if (rc2)
1654                         return rc2;
1655         }
1656         return rc;
1657 }
1658
1659 /* Check whether a task has a particular permission to an inode.
1660    The 'adp' parameter is optional and allows other audit
1661    data to be passed (e.g. the dentry). */
1662 static int inode_has_perm(const struct cred *cred,
1663                           struct inode *inode,
1664                           u32 perms,
1665                           struct common_audit_data *adp)
1666 {
1667         struct inode_security_struct *isec;
1668         u32 sid;
1669
1670         if (unlikely(IS_PRIVATE(inode)))
1671                 return 0;
1672
1673         sid = cred_sid(cred);
1674         isec = selinux_inode(inode);
1675
1676         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1677 }
1678
1679 /* Same as inode_has_perm, but pass explicit audit data containing
1680    the dentry to help the auditing code to more easily generate the
1681    pathname if needed. */
1682 static inline int dentry_has_perm(const struct cred *cred,
1683                                   struct dentry *dentry,
1684                                   u32 av)
1685 {
1686         struct inode *inode = d_backing_inode(dentry);
1687         struct common_audit_data ad;
1688
1689         ad.type = LSM_AUDIT_DATA_DENTRY;
1690         ad.u.dentry = dentry;
1691         __inode_security_revalidate(inode, dentry, true);
1692         return inode_has_perm(cred, inode, av, &ad);
1693 }
1694
1695 /* Same as inode_has_perm, but pass explicit audit data containing
1696    the path to help the auditing code to more easily generate the
1697    pathname if needed. */
1698 static inline int path_has_perm(const struct cred *cred,
1699                                 const struct path *path,
1700                                 u32 av)
1701 {
1702         struct inode *inode = d_backing_inode(path->dentry);
1703         struct common_audit_data ad;
1704
1705         ad.type = LSM_AUDIT_DATA_PATH;
1706         ad.u.path = *path;
1707         __inode_security_revalidate(inode, path->dentry, true);
1708         return inode_has_perm(cred, inode, av, &ad);
1709 }
1710
1711 /* Same as path_has_perm, but uses the inode from the file struct. */
1712 static inline int file_path_has_perm(const struct cred *cred,
1713                                      struct file *file,
1714                                      u32 av)
1715 {
1716         struct common_audit_data ad;
1717
1718         ad.type = LSM_AUDIT_DATA_FILE;
1719         ad.u.file = file;
1720         return inode_has_perm(cred, file_inode(file), av, &ad);
1721 }
1722
1723 #ifdef CONFIG_BPF_SYSCALL
1724 static int bpf_fd_pass(const struct file *file, u32 sid);
1725 #endif
1726
1727 /* Check whether a task can use an open file descriptor to
1728    access an inode in a given way.  Check access to the
1729    descriptor itself, and then use dentry_has_perm to
1730    check a particular permission to the file.
1731    Access to the descriptor is implicitly granted if it
1732    has the same SID as the process.  If av is zero, then
1733    access to the file is not checked, e.g. for cases
1734    where only the descriptor is affected like seek. */
1735 static int file_has_perm(const struct cred *cred,
1736                          struct file *file,
1737                          u32 av)
1738 {
1739         struct file_security_struct *fsec = selinux_file(file);
1740         struct inode *inode = file_inode(file);
1741         struct common_audit_data ad;
1742         u32 sid = cred_sid(cred);
1743         int rc;
1744
1745         ad.type = LSM_AUDIT_DATA_FILE;
1746         ad.u.file = file;
1747
1748         if (sid != fsec->sid) {
1749                 rc = avc_has_perm(sid, fsec->sid,
1750                                   SECCLASS_FD,
1751                                   FD__USE,
1752                                   &ad);
1753                 if (rc)
1754                         goto out;
1755         }
1756
1757 #ifdef CONFIG_BPF_SYSCALL
1758         rc = bpf_fd_pass(file, cred_sid(cred));
1759         if (rc)
1760                 return rc;
1761 #endif
1762
1763         /* av is zero if only checking access to the descriptor. */
1764         rc = 0;
1765         if (av)
1766                 rc = inode_has_perm(cred, inode, av, &ad);
1767
1768 out:
1769         return rc;
1770 }
1771
1772 /*
1773  * Determine the label for an inode that might be unioned.
1774  */
1775 static int
1776 selinux_determine_inode_label(const struct task_security_struct *tsec,
1777                                  struct inode *dir,
1778                                  const struct qstr *name, u16 tclass,
1779                                  u32 *_new_isid)
1780 {
1781         const struct superblock_security_struct *sbsec =
1782                                                 selinux_superblock(dir->i_sb);
1783
1784         if ((sbsec->flags & SE_SBINITIALIZED) &&
1785             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1786                 *_new_isid = sbsec->mntpoint_sid;
1787         } else if ((sbsec->flags & SBLABEL_MNT) &&
1788                    tsec->create_sid) {
1789                 *_new_isid = tsec->create_sid;
1790         } else {
1791                 const struct inode_security_struct *dsec = inode_security(dir);
1792                 return security_transition_sid(tsec->sid,
1793                                                dsec->sid, tclass,
1794                                                name, _new_isid);
1795         }
1796
1797         return 0;
1798 }
1799
1800 /* Check whether a task can create a file. */
1801 static int may_create(struct inode *dir,
1802                       struct dentry *dentry,
1803                       u16 tclass)
1804 {
1805         const struct task_security_struct *tsec = selinux_cred(current_cred());
1806         struct inode_security_struct *dsec;
1807         struct superblock_security_struct *sbsec;
1808         u32 sid, newsid;
1809         struct common_audit_data ad;
1810         int rc;
1811
1812         dsec = inode_security(dir);
1813         sbsec = selinux_superblock(dir->i_sb);
1814
1815         sid = tsec->sid;
1816
1817         ad.type = LSM_AUDIT_DATA_DENTRY;
1818         ad.u.dentry = dentry;
1819
1820         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1821                           DIR__ADD_NAME | DIR__SEARCH,
1822                           &ad);
1823         if (rc)
1824                 return rc;
1825
1826         rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1827                                            &newsid);
1828         if (rc)
1829                 return rc;
1830
1831         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1832         if (rc)
1833                 return rc;
1834
1835         return avc_has_perm(newsid, sbsec->sid,
1836                             SECCLASS_FILESYSTEM,
1837                             FILESYSTEM__ASSOCIATE, &ad);
1838 }
1839
1840 #define MAY_LINK        0
1841 #define MAY_UNLINK      1
1842 #define MAY_RMDIR       2
1843
1844 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1845 static int may_link(struct inode *dir,
1846                     struct dentry *dentry,
1847                     int kind)
1848
1849 {
1850         struct inode_security_struct *dsec, *isec;
1851         struct common_audit_data ad;
1852         u32 sid = current_sid();
1853         u32 av;
1854         int rc;
1855
1856         dsec = inode_security(dir);
1857         isec = backing_inode_security(dentry);
1858
1859         ad.type = LSM_AUDIT_DATA_DENTRY;
1860         ad.u.dentry = dentry;
1861
1862         av = DIR__SEARCH;
1863         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1864         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1865         if (rc)
1866                 return rc;
1867
1868         switch (kind) {
1869         case MAY_LINK:
1870                 av = FILE__LINK;
1871                 break;
1872         case MAY_UNLINK:
1873                 av = FILE__UNLINK;
1874                 break;
1875         case MAY_RMDIR:
1876                 av = DIR__RMDIR;
1877                 break;
1878         default:
1879                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
1880                         __func__, kind);
1881                 return 0;
1882         }
1883
1884         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1885         return rc;
1886 }
1887
1888 static inline int may_rename(struct inode *old_dir,
1889                              struct dentry *old_dentry,
1890                              struct inode *new_dir,
1891                              struct dentry *new_dentry)
1892 {
1893         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1894         struct common_audit_data ad;
1895         u32 sid = current_sid();
1896         u32 av;
1897         int old_is_dir, new_is_dir;
1898         int rc;
1899
1900         old_dsec = inode_security(old_dir);
1901         old_isec = backing_inode_security(old_dentry);
1902         old_is_dir = d_is_dir(old_dentry);
1903         new_dsec = inode_security(new_dir);
1904
1905         ad.type = LSM_AUDIT_DATA_DENTRY;
1906
1907         ad.u.dentry = old_dentry;
1908         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1909                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1910         if (rc)
1911                 return rc;
1912         rc = avc_has_perm(sid, old_isec->sid,
1913                           old_isec->sclass, FILE__RENAME, &ad);
1914         if (rc)
1915                 return rc;
1916         if (old_is_dir && new_dir != old_dir) {
1917                 rc = avc_has_perm(sid, old_isec->sid,
1918                                   old_isec->sclass, DIR__REPARENT, &ad);
1919                 if (rc)
1920                         return rc;
1921         }
1922
1923         ad.u.dentry = new_dentry;
1924         av = DIR__ADD_NAME | DIR__SEARCH;
1925         if (d_is_positive(new_dentry))
1926                 av |= DIR__REMOVE_NAME;
1927         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1928         if (rc)
1929                 return rc;
1930         if (d_is_positive(new_dentry)) {
1931                 new_isec = backing_inode_security(new_dentry);
1932                 new_is_dir = d_is_dir(new_dentry);
1933                 rc = avc_has_perm(sid, new_isec->sid,
1934                                   new_isec->sclass,
1935                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1936                 if (rc)
1937                         return rc;
1938         }
1939
1940         return 0;
1941 }
1942
1943 /* Check whether a task can perform a filesystem operation. */
1944 static int superblock_has_perm(const struct cred *cred,
1945                                const struct super_block *sb,
1946                                u32 perms,
1947                                struct common_audit_data *ad)
1948 {
1949         struct superblock_security_struct *sbsec;
1950         u32 sid = cred_sid(cred);
1951
1952         sbsec = selinux_superblock(sb);
1953         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1954 }
1955
1956 /* Convert a Linux mode and permission mask to an access vector. */
1957 static inline u32 file_mask_to_av(int mode, int mask)
1958 {
1959         u32 av = 0;
1960
1961         if (!S_ISDIR(mode)) {
1962                 if (mask & MAY_EXEC)
1963                         av |= FILE__EXECUTE;
1964                 if (mask & MAY_READ)
1965                         av |= FILE__READ;
1966
1967                 if (mask & MAY_APPEND)
1968                         av |= FILE__APPEND;
1969                 else if (mask & MAY_WRITE)
1970                         av |= FILE__WRITE;
1971
1972         } else {
1973                 if (mask & MAY_EXEC)
1974                         av |= DIR__SEARCH;
1975                 if (mask & MAY_WRITE)
1976                         av |= DIR__WRITE;
1977                 if (mask & MAY_READ)
1978                         av |= DIR__READ;
1979         }
1980
1981         return av;
1982 }
1983
1984 /* Convert a Linux file to an access vector. */
1985 static inline u32 file_to_av(const struct file *file)
1986 {
1987         u32 av = 0;
1988
1989         if (file->f_mode & FMODE_READ)
1990                 av |= FILE__READ;
1991         if (file->f_mode & FMODE_WRITE) {
1992                 if (file->f_flags & O_APPEND)
1993                         av |= FILE__APPEND;
1994                 else
1995                         av |= FILE__WRITE;
1996         }
1997         if (!av) {
1998                 /*
1999                  * Special file opened with flags 3 for ioctl-only use.
2000                  */
2001                 av = FILE__IOCTL;
2002         }
2003
2004         return av;
2005 }
2006
2007 /*
2008  * Convert a file to an access vector and include the correct
2009  * open permission.
2010  */
2011 static inline u32 open_file_to_av(struct file *file)
2012 {
2013         u32 av = file_to_av(file);
2014         struct inode *inode = file_inode(file);
2015
2016         if (selinux_policycap_openperm() &&
2017             inode->i_sb->s_magic != SOCKFS_MAGIC)
2018                 av |= FILE__OPEN;
2019
2020         return av;
2021 }
2022
2023 /* Hook functions begin here. */
2024
2025 static int selinux_binder_set_context_mgr(const struct cred *mgr)
2026 {
2027         return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2028                             BINDER__SET_CONTEXT_MGR, NULL);
2029 }
2030
2031 static int selinux_binder_transaction(const struct cred *from,
2032                                       const struct cred *to)
2033 {
2034         u32 mysid = current_sid();
2035         u32 fromsid = cred_sid(from);
2036         u32 tosid = cred_sid(to);
2037         int rc;
2038
2039         if (mysid != fromsid) {
2040                 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2041                                   BINDER__IMPERSONATE, NULL);
2042                 if (rc)
2043                         return rc;
2044         }
2045
2046         return avc_has_perm(fromsid, tosid,
2047                             SECCLASS_BINDER, BINDER__CALL, NULL);
2048 }
2049
2050 static int selinux_binder_transfer_binder(const struct cred *from,
2051                                           const struct cred *to)
2052 {
2053         return avc_has_perm(cred_sid(from), cred_sid(to),
2054                             SECCLASS_BINDER, BINDER__TRANSFER,
2055                             NULL);
2056 }
2057
2058 static int selinux_binder_transfer_file(const struct cred *from,
2059                                         const struct cred *to,
2060                                         const struct file *file)
2061 {
2062         u32 sid = cred_sid(to);
2063         struct file_security_struct *fsec = selinux_file(file);
2064         struct dentry *dentry = file->f_path.dentry;
2065         struct inode_security_struct *isec;
2066         struct common_audit_data ad;
2067         int rc;
2068
2069         ad.type = LSM_AUDIT_DATA_PATH;
2070         ad.u.path = file->f_path;
2071
2072         if (sid != fsec->sid) {
2073                 rc = avc_has_perm(sid, fsec->sid,
2074                                   SECCLASS_FD,
2075                                   FD__USE,
2076                                   &ad);
2077                 if (rc)
2078                         return rc;
2079         }
2080
2081 #ifdef CONFIG_BPF_SYSCALL
2082         rc = bpf_fd_pass(file, sid);
2083         if (rc)
2084                 return rc;
2085 #endif
2086
2087         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2088                 return 0;
2089
2090         isec = backing_inode_security(dentry);
2091         return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2092                             &ad);
2093 }
2094
2095 static int selinux_ptrace_access_check(struct task_struct *child,
2096                                        unsigned int mode)
2097 {
2098         u32 sid = current_sid();
2099         u32 csid = task_sid_obj(child);
2100
2101         if (mode & PTRACE_MODE_READ)
2102                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2103                                 NULL);
2104
2105         return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2106                         NULL);
2107 }
2108
2109 static int selinux_ptrace_traceme(struct task_struct *parent)
2110 {
2111         return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2112                             SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2113 }
2114
2115 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2116                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2117 {
2118         return avc_has_perm(current_sid(), task_sid_obj(target),
2119                         SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2120 }
2121
2122 static int selinux_capset(struct cred *new, const struct cred *old,
2123                           const kernel_cap_t *effective,
2124                           const kernel_cap_t *inheritable,
2125                           const kernel_cap_t *permitted)
2126 {
2127         return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2128                             PROCESS__SETCAP, NULL);
2129 }
2130
2131 /*
2132  * (This comment used to live with the selinux_task_setuid hook,
2133  * which was removed).
2134  *
2135  * Since setuid only affects the current process, and since the SELinux
2136  * controls are not based on the Linux identity attributes, SELinux does not
2137  * need to control this operation.  However, SELinux does control the use of
2138  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2139  */
2140
2141 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2142                            int cap, unsigned int opts)
2143 {
2144         return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2145 }
2146
2147 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2148 {
2149         const struct cred *cred = current_cred();
2150         int rc = 0;
2151
2152         if (!sb)
2153                 return 0;
2154
2155         switch (cmds) {
2156         case Q_SYNC:
2157         case Q_QUOTAON:
2158         case Q_QUOTAOFF:
2159         case Q_SETINFO:
2160         case Q_SETQUOTA:
2161         case Q_XQUOTAOFF:
2162         case Q_XQUOTAON:
2163         case Q_XSETQLIM:
2164                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2165                 break;
2166         case Q_GETFMT:
2167         case Q_GETINFO:
2168         case Q_GETQUOTA:
2169         case Q_XGETQUOTA:
2170         case Q_XGETQSTAT:
2171         case Q_XGETQSTATV:
2172         case Q_XGETNEXTQUOTA:
2173                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2174                 break;
2175         default:
2176                 rc = 0;  /* let the kernel handle invalid cmds */
2177                 break;
2178         }
2179         return rc;
2180 }
2181
2182 static int selinux_quota_on(struct dentry *dentry)
2183 {
2184         const struct cred *cred = current_cred();
2185
2186         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2187 }
2188
2189 static int selinux_syslog(int type)
2190 {
2191         switch (type) {
2192         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2193         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2194                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2195                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2196         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2197         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2198         /* Set level of messages printed to console */
2199         case SYSLOG_ACTION_CONSOLE_LEVEL:
2200                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2201                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2202                                     NULL);
2203         }
2204         /* All other syslog types */
2205         return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2206                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2207 }
2208
2209 /*
2210  * Check permission for allocating a new virtual mapping. Returns
2211  * 0 if permission is granted, negative error code if not.
2212  *
2213  * Do not audit the selinux permission check, as this is applied to all
2214  * processes that allocate mappings.
2215  */
2216 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2217 {
2218         return cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2219                                    CAP_OPT_NOAUDIT, true);
2220 }
2221
2222 /* binprm security operations */
2223
2224 static u32 ptrace_parent_sid(void)
2225 {
2226         u32 sid = 0;
2227         struct task_struct *tracer;
2228
2229         rcu_read_lock();
2230         tracer = ptrace_parent(current);
2231         if (tracer)
2232                 sid = task_sid_obj(tracer);
2233         rcu_read_unlock();
2234
2235         return sid;
2236 }
2237
2238 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2239                             const struct task_security_struct *old_tsec,
2240                             const struct task_security_struct *new_tsec)
2241 {
2242         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2243         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2244         int rc;
2245         u32 av;
2246
2247         if (!nnp && !nosuid)
2248                 return 0; /* neither NNP nor nosuid */
2249
2250         if (new_tsec->sid == old_tsec->sid)
2251                 return 0; /* No change in credentials */
2252
2253         /*
2254          * If the policy enables the nnp_nosuid_transition policy capability,
2255          * then we permit transitions under NNP or nosuid if the
2256          * policy allows the corresponding permission between
2257          * the old and new contexts.
2258          */
2259         if (selinux_policycap_nnp_nosuid_transition()) {
2260                 av = 0;
2261                 if (nnp)
2262                         av |= PROCESS2__NNP_TRANSITION;
2263                 if (nosuid)
2264                         av |= PROCESS2__NOSUID_TRANSITION;
2265                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2266                                   SECCLASS_PROCESS2, av, NULL);
2267                 if (!rc)
2268                         return 0;
2269         }
2270
2271         /*
2272          * We also permit NNP or nosuid transitions to bounded SIDs,
2273          * i.e. SIDs that are guaranteed to only be allowed a subset
2274          * of the permissions of the current SID.
2275          */
2276         rc = security_bounded_transition(old_tsec->sid,
2277                                          new_tsec->sid);
2278         if (!rc)
2279                 return 0;
2280
2281         /*
2282          * On failure, preserve the errno values for NNP vs nosuid.
2283          * NNP:  Operation not permitted for caller.
2284          * nosuid:  Permission denied to file.
2285          */
2286         if (nnp)
2287                 return -EPERM;
2288         return -EACCES;
2289 }
2290
2291 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2292 {
2293         const struct task_security_struct *old_tsec;
2294         struct task_security_struct *new_tsec;
2295         struct inode_security_struct *isec;
2296         struct common_audit_data ad;
2297         struct inode *inode = file_inode(bprm->file);
2298         int rc;
2299
2300         /* SELinux context only depends on initial program or script and not
2301          * the script interpreter */
2302
2303         old_tsec = selinux_cred(current_cred());
2304         new_tsec = selinux_cred(bprm->cred);
2305         isec = inode_security(inode);
2306
2307         /* Default to the current task SID. */
2308         new_tsec->sid = old_tsec->sid;
2309         new_tsec->osid = old_tsec->sid;
2310
2311         /* Reset fs, key, and sock SIDs on execve. */
2312         new_tsec->create_sid = 0;
2313         new_tsec->keycreate_sid = 0;
2314         new_tsec->sockcreate_sid = 0;
2315
2316         /*
2317          * Before policy is loaded, label any task outside kernel space
2318          * as SECINITSID_INIT, so that any userspace tasks surviving from
2319          * early boot end up with a label different from SECINITSID_KERNEL
2320          * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2321          */
2322         if (!selinux_initialized()) {
2323                 new_tsec->sid = SECINITSID_INIT;
2324                 /* also clear the exec_sid just in case */
2325                 new_tsec->exec_sid = 0;
2326                 return 0;
2327         }
2328
2329         if (old_tsec->exec_sid) {
2330                 new_tsec->sid = old_tsec->exec_sid;
2331                 /* Reset exec SID on execve. */
2332                 new_tsec->exec_sid = 0;
2333
2334                 /* Fail on NNP or nosuid if not an allowed transition. */
2335                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2336                 if (rc)
2337                         return rc;
2338         } else {
2339                 /* Check for a default transition on this program. */
2340                 rc = security_transition_sid(old_tsec->sid,
2341                                              isec->sid, SECCLASS_PROCESS, NULL,
2342                                              &new_tsec->sid);
2343                 if (rc)
2344                         return rc;
2345
2346                 /*
2347                  * Fallback to old SID on NNP or nosuid if not an allowed
2348                  * transition.
2349                  */
2350                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2351                 if (rc)
2352                         new_tsec->sid = old_tsec->sid;
2353         }
2354
2355         ad.type = LSM_AUDIT_DATA_FILE;
2356         ad.u.file = bprm->file;
2357
2358         if (new_tsec->sid == old_tsec->sid) {
2359                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2360                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2361                 if (rc)
2362                         return rc;
2363         } else {
2364                 /* Check permissions for the transition. */
2365                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2366                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2367                 if (rc)
2368                         return rc;
2369
2370                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2371                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2372                 if (rc)
2373                         return rc;
2374
2375                 /* Check for shared state */
2376                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2377                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2378                                           SECCLASS_PROCESS, PROCESS__SHARE,
2379                                           NULL);
2380                         if (rc)
2381                                 return -EPERM;
2382                 }
2383
2384                 /* Make sure that anyone attempting to ptrace over a task that
2385                  * changes its SID has the appropriate permit */
2386                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2387                         u32 ptsid = ptrace_parent_sid();
2388                         if (ptsid != 0) {
2389                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2390                                                   SECCLASS_PROCESS,
2391                                                   PROCESS__PTRACE, NULL);
2392                                 if (rc)
2393                                         return -EPERM;
2394                         }
2395                 }
2396
2397                 /* Clear any possibly unsafe personality bits on exec: */
2398                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2399
2400                 /* Enable secure mode for SIDs transitions unless
2401                    the noatsecure permission is granted between
2402                    the two SIDs, i.e. ahp returns 0. */
2403                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2404                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2405                                   NULL);
2406                 bprm->secureexec |= !!rc;
2407         }
2408
2409         return 0;
2410 }
2411
2412 static int match_file(const void *p, struct file *file, unsigned fd)
2413 {
2414         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2415 }
2416
2417 /* Derived from fs/exec.c:flush_old_files. */
2418 static inline void flush_unauthorized_files(const struct cred *cred,
2419                                             struct files_struct *files)
2420 {
2421         struct file *file, *devnull = NULL;
2422         struct tty_struct *tty;
2423         int drop_tty = 0;
2424         unsigned n;
2425
2426         tty = get_current_tty();
2427         if (tty) {
2428                 spin_lock(&tty->files_lock);
2429                 if (!list_empty(&tty->tty_files)) {
2430                         struct tty_file_private *file_priv;
2431
2432                         /* Revalidate access to controlling tty.
2433                            Use file_path_has_perm on the tty path directly
2434                            rather than using file_has_perm, as this particular
2435                            open file may belong to another process and we are
2436                            only interested in the inode-based check here. */
2437                         file_priv = list_first_entry(&tty->tty_files,
2438                                                 struct tty_file_private, list);
2439                         file = file_priv->file;
2440                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2441                                 drop_tty = 1;
2442                 }
2443                 spin_unlock(&tty->files_lock);
2444                 tty_kref_put(tty);
2445         }
2446         /* Reset controlling tty. */
2447         if (drop_tty)
2448                 no_tty();
2449
2450         /* Revalidate access to inherited open files. */
2451         n = iterate_fd(files, 0, match_file, cred);
2452         if (!n) /* none found? */
2453                 return;
2454
2455         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2456         if (IS_ERR(devnull))
2457                 devnull = NULL;
2458         /* replace all the matching ones with this */
2459         do {
2460                 replace_fd(n - 1, devnull, 0);
2461         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2462         if (devnull)
2463                 fput(devnull);
2464 }
2465
2466 /*
2467  * Prepare a process for imminent new credential changes due to exec
2468  */
2469 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2470 {
2471         struct task_security_struct *new_tsec;
2472         struct rlimit *rlim, *initrlim;
2473         int rc, i;
2474
2475         new_tsec = selinux_cred(bprm->cred);
2476         if (new_tsec->sid == new_tsec->osid)
2477                 return;
2478
2479         /* Close files for which the new task SID is not authorized. */
2480         flush_unauthorized_files(bprm->cred, current->files);
2481
2482         /* Always clear parent death signal on SID transitions. */
2483         current->pdeath_signal = 0;
2484
2485         /* Check whether the new SID can inherit resource limits from the old
2486          * SID.  If not, reset all soft limits to the lower of the current
2487          * task's hard limit and the init task's soft limit.
2488          *
2489          * Note that the setting of hard limits (even to lower them) can be
2490          * controlled by the setrlimit check.  The inclusion of the init task's
2491          * soft limit into the computation is to avoid resetting soft limits
2492          * higher than the default soft limit for cases where the default is
2493          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2494          */
2495         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2496                           PROCESS__RLIMITINH, NULL);
2497         if (rc) {
2498                 /* protect against do_prlimit() */
2499                 task_lock(current);
2500                 for (i = 0; i < RLIM_NLIMITS; i++) {
2501                         rlim = current->signal->rlim + i;
2502                         initrlim = init_task.signal->rlim + i;
2503                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2504                 }
2505                 task_unlock(current);
2506                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2507                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2508         }
2509 }
2510
2511 /*
2512  * Clean up the process immediately after the installation of new credentials
2513  * due to exec
2514  */
2515 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2516 {
2517         const struct task_security_struct *tsec = selinux_cred(current_cred());
2518         u32 osid, sid;
2519         int rc;
2520
2521         osid = tsec->osid;
2522         sid = tsec->sid;
2523
2524         if (sid == osid)
2525                 return;
2526
2527         /* Check whether the new SID can inherit signal state from the old SID.
2528          * If not, clear itimers to avoid subsequent signal generation and
2529          * flush and unblock signals.
2530          *
2531          * This must occur _after_ the task SID has been updated so that any
2532          * kill done after the flush will be checked against the new SID.
2533          */
2534         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2535         if (rc) {
2536                 clear_itimer();
2537
2538                 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2539                 if (!fatal_signal_pending(current)) {
2540                         flush_sigqueue(&current->pending);
2541                         flush_sigqueue(&current->signal->shared_pending);
2542                         flush_signal_handlers(current, 1);
2543                         sigemptyset(&current->blocked);
2544                         recalc_sigpending();
2545                 }
2546                 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2547         }
2548
2549         /* Wake up the parent if it is waiting so that it can recheck
2550          * wait permission to the new task SID. */
2551         read_lock(&tasklist_lock);
2552         __wake_up_parent(current, unrcu_pointer(current->real_parent));
2553         read_unlock(&tasklist_lock);
2554 }
2555
2556 /* superblock security operations */
2557
2558 static int selinux_sb_alloc_security(struct super_block *sb)
2559 {
2560         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2561
2562         mutex_init(&sbsec->lock);
2563         INIT_LIST_HEAD(&sbsec->isec_head);
2564         spin_lock_init(&sbsec->isec_lock);
2565         sbsec->sid = SECINITSID_UNLABELED;
2566         sbsec->def_sid = SECINITSID_FILE;
2567         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2568
2569         return 0;
2570 }
2571
2572 static inline int opt_len(const char *s)
2573 {
2574         bool open_quote = false;
2575         int len;
2576         char c;
2577
2578         for (len = 0; (c = s[len]) != '\0'; len++) {
2579                 if (c == '"')
2580                         open_quote = !open_quote;
2581                 if (c == ',' && !open_quote)
2582                         break;
2583         }
2584         return len;
2585 }
2586
2587 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2588 {
2589         char *from = options;
2590         char *to = options;
2591         bool first = true;
2592         int rc;
2593
2594         while (1) {
2595                 int len = opt_len(from);
2596                 int token;
2597                 char *arg = NULL;
2598
2599                 token = match_opt_prefix(from, len, &arg);
2600
2601                 if (token != Opt_error) {
2602                         char *p, *q;
2603
2604                         /* strip quotes */
2605                         if (arg) {
2606                                 for (p = q = arg; p < from + len; p++) {
2607                                         char c = *p;
2608                                         if (c != '"')
2609                                                 *q++ = c;
2610                                 }
2611                                 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2612                                 if (!arg) {
2613                                         rc = -ENOMEM;
2614                                         goto free_opt;
2615                                 }
2616                         }
2617                         rc = selinux_add_opt(token, arg, mnt_opts);
2618                         kfree(arg);
2619                         arg = NULL;
2620                         if (unlikely(rc)) {
2621                                 goto free_opt;
2622                         }
2623                 } else {
2624                         if (!first) {   // copy with preceding comma
2625                                 from--;
2626                                 len++;
2627                         }
2628                         if (to != from)
2629                                 memmove(to, from, len);
2630                         to += len;
2631                         first = false;
2632                 }
2633                 if (!from[len])
2634                         break;
2635                 from += len + 1;
2636         }
2637         *to = '\0';
2638         return 0;
2639
2640 free_opt:
2641         if (*mnt_opts) {
2642                 selinux_free_mnt_opts(*mnt_opts);
2643                 *mnt_opts = NULL;
2644         }
2645         return rc;
2646 }
2647
2648 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2649 {
2650         struct selinux_mnt_opts *opts = mnt_opts;
2651         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2652
2653         /*
2654          * Superblock not initialized (i.e. no options) - reject if any
2655          * options specified, otherwise accept.
2656          */
2657         if (!(sbsec->flags & SE_SBINITIALIZED))
2658                 return opts ? 1 : 0;
2659
2660         /*
2661          * Superblock initialized and no options specified - reject if
2662          * superblock has any options set, otherwise accept.
2663          */
2664         if (!opts)
2665                 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2666
2667         if (opts->fscontext_sid) {
2668                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2669                                opts->fscontext_sid))
2670                         return 1;
2671         }
2672         if (opts->context_sid) {
2673                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2674                                opts->context_sid))
2675                         return 1;
2676         }
2677         if (opts->rootcontext_sid) {
2678                 struct inode_security_struct *root_isec;
2679
2680                 root_isec = backing_inode_security(sb->s_root);
2681                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2682                                opts->rootcontext_sid))
2683                         return 1;
2684         }
2685         if (opts->defcontext_sid) {
2686                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2687                                opts->defcontext_sid))
2688                         return 1;
2689         }
2690         return 0;
2691 }
2692
2693 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2694 {
2695         struct selinux_mnt_opts *opts = mnt_opts;
2696         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2697
2698         if (!(sbsec->flags & SE_SBINITIALIZED))
2699                 return 0;
2700
2701         if (!opts)
2702                 return 0;
2703
2704         if (opts->fscontext_sid) {
2705                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2706                                opts->fscontext_sid))
2707                         goto out_bad_option;
2708         }
2709         if (opts->context_sid) {
2710                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2711                                opts->context_sid))
2712                         goto out_bad_option;
2713         }
2714         if (opts->rootcontext_sid) {
2715                 struct inode_security_struct *root_isec;
2716                 root_isec = backing_inode_security(sb->s_root);
2717                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2718                                opts->rootcontext_sid))
2719                         goto out_bad_option;
2720         }
2721         if (opts->defcontext_sid) {
2722                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2723                                opts->defcontext_sid))
2724                         goto out_bad_option;
2725         }
2726         return 0;
2727
2728 out_bad_option:
2729         pr_warn("SELinux: unable to change security options "
2730                "during remount (dev %s, type=%s)\n", sb->s_id,
2731                sb->s_type->name);
2732         return -EINVAL;
2733 }
2734
2735 static int selinux_sb_kern_mount(const struct super_block *sb)
2736 {
2737         const struct cred *cred = current_cred();
2738         struct common_audit_data ad;
2739
2740         ad.type = LSM_AUDIT_DATA_DENTRY;
2741         ad.u.dentry = sb->s_root;
2742         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2743 }
2744
2745 static int selinux_sb_statfs(struct dentry *dentry)
2746 {
2747         const struct cred *cred = current_cred();
2748         struct common_audit_data ad;
2749
2750         ad.type = LSM_AUDIT_DATA_DENTRY;
2751         ad.u.dentry = dentry->d_sb->s_root;
2752         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2753 }
2754
2755 static int selinux_mount(const char *dev_name,
2756                          const struct path *path,
2757                          const char *type,
2758                          unsigned long flags,
2759                          void *data)
2760 {
2761         const struct cred *cred = current_cred();
2762
2763         if (flags & MS_REMOUNT)
2764                 return superblock_has_perm(cred, path->dentry->d_sb,
2765                                            FILESYSTEM__REMOUNT, NULL);
2766         else
2767                 return path_has_perm(cred, path, FILE__MOUNTON);
2768 }
2769
2770 static int selinux_move_mount(const struct path *from_path,
2771                               const struct path *to_path)
2772 {
2773         const struct cred *cred = current_cred();
2774
2775         return path_has_perm(cred, to_path, FILE__MOUNTON);
2776 }
2777
2778 static int selinux_umount(struct vfsmount *mnt, int flags)
2779 {
2780         const struct cred *cred = current_cred();
2781
2782         return superblock_has_perm(cred, mnt->mnt_sb,
2783                                    FILESYSTEM__UNMOUNT, NULL);
2784 }
2785
2786 static int selinux_fs_context_submount(struct fs_context *fc,
2787                                    struct super_block *reference)
2788 {
2789         const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2790         struct selinux_mnt_opts *opts;
2791
2792         /*
2793          * Ensure that fc->security remains NULL when no options are set
2794          * as expected by selinux_set_mnt_opts().
2795          */
2796         if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2797                 return 0;
2798
2799         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2800         if (!opts)
2801                 return -ENOMEM;
2802
2803         if (sbsec->flags & FSCONTEXT_MNT)
2804                 opts->fscontext_sid = sbsec->sid;
2805         if (sbsec->flags & CONTEXT_MNT)
2806                 opts->context_sid = sbsec->mntpoint_sid;
2807         if (sbsec->flags & DEFCONTEXT_MNT)
2808                 opts->defcontext_sid = sbsec->def_sid;
2809         fc->security = opts;
2810         return 0;
2811 }
2812
2813 static int selinux_fs_context_dup(struct fs_context *fc,
2814                                   struct fs_context *src_fc)
2815 {
2816         const struct selinux_mnt_opts *src = src_fc->security;
2817
2818         if (!src)
2819                 return 0;
2820
2821         fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2822         return fc->security ? 0 : -ENOMEM;
2823 }
2824
2825 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2826         fsparam_string(CONTEXT_STR,     Opt_context),
2827         fsparam_string(DEFCONTEXT_STR,  Opt_defcontext),
2828         fsparam_string(FSCONTEXT_STR,   Opt_fscontext),
2829         fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2830         fsparam_flag  (SECLABEL_STR,    Opt_seclabel),
2831         {}
2832 };
2833
2834 static int selinux_fs_context_parse_param(struct fs_context *fc,
2835                                           struct fs_parameter *param)
2836 {
2837         struct fs_parse_result result;
2838         int opt;
2839
2840         opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2841         if (opt < 0)
2842                 return opt;
2843
2844         return selinux_add_opt(opt, param->string, &fc->security);
2845 }
2846
2847 /* inode security operations */
2848
2849 static int selinux_inode_alloc_security(struct inode *inode)
2850 {
2851         struct inode_security_struct *isec = selinux_inode(inode);
2852         u32 sid = current_sid();
2853
2854         spin_lock_init(&isec->lock);
2855         INIT_LIST_HEAD(&isec->list);
2856         isec->inode = inode;
2857         isec->sid = SECINITSID_UNLABELED;
2858         isec->sclass = SECCLASS_FILE;
2859         isec->task_sid = sid;
2860         isec->initialized = LABEL_INVALID;
2861
2862         return 0;
2863 }
2864
2865 static void selinux_inode_free_security(struct inode *inode)
2866 {
2867         inode_free_security(inode);
2868 }
2869
2870 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2871                                         const struct qstr *name,
2872                                         const char **xattr_name,
2873                                         struct lsm_context *cp)
2874 {
2875         u32 newsid;
2876         int rc;
2877
2878         rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2879                                            d_inode(dentry->d_parent), name,
2880                                            inode_mode_to_security_class(mode),
2881                                            &newsid);
2882         if (rc)
2883                 return rc;
2884
2885         if (xattr_name)
2886                 *xattr_name = XATTR_NAME_SELINUX;
2887
2888         cp->id = LSM_ID_SELINUX;
2889         return security_sid_to_context(newsid, &cp->context, &cp->len);
2890 }
2891
2892 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2893                                           struct qstr *name,
2894                                           const struct cred *old,
2895                                           struct cred *new)
2896 {
2897         u32 newsid;
2898         int rc;
2899         struct task_security_struct *tsec;
2900
2901         rc = selinux_determine_inode_label(selinux_cred(old),
2902                                            d_inode(dentry->d_parent), name,
2903                                            inode_mode_to_security_class(mode),
2904                                            &newsid);
2905         if (rc)
2906                 return rc;
2907
2908         tsec = selinux_cred(new);
2909         tsec->create_sid = newsid;
2910         return 0;
2911 }
2912
2913 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2914                                        const struct qstr *qstr,
2915                                        struct xattr *xattrs, int *xattr_count)
2916 {
2917         const struct task_security_struct *tsec = selinux_cred(current_cred());
2918         struct superblock_security_struct *sbsec;
2919         struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2920         u32 newsid, clen;
2921         u16 newsclass;
2922         int rc;
2923         char *context;
2924
2925         sbsec = selinux_superblock(dir->i_sb);
2926
2927         newsid = tsec->create_sid;
2928         newsclass = inode_mode_to_security_class(inode->i_mode);
2929         rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid);
2930         if (rc)
2931                 return rc;
2932
2933         /* Possibly defer initialization to selinux_complete_init. */
2934         if (sbsec->flags & SE_SBINITIALIZED) {
2935                 struct inode_security_struct *isec = selinux_inode(inode);
2936                 isec->sclass = newsclass;
2937                 isec->sid = newsid;
2938                 isec->initialized = LABEL_INITIALIZED;
2939         }
2940
2941         if (!selinux_initialized() ||
2942             !(sbsec->flags & SBLABEL_MNT))
2943                 return -EOPNOTSUPP;
2944
2945         if (xattr) {
2946                 rc = security_sid_to_context_force(newsid,
2947                                                    &context, &clen);
2948                 if (rc)
2949                         return rc;
2950                 xattr->value = context;
2951                 xattr->value_len = clen;
2952                 xattr->name = XATTR_SELINUX_SUFFIX;
2953         }
2954
2955         return 0;
2956 }
2957
2958 static int selinux_inode_init_security_anon(struct inode *inode,
2959                                             const struct qstr *name,
2960                                             const struct inode *context_inode)
2961 {
2962         u32 sid = current_sid();
2963         struct common_audit_data ad;
2964         struct inode_security_struct *isec;
2965         int rc;
2966
2967         if (unlikely(!selinux_initialized()))
2968                 return 0;
2969
2970         isec = selinux_inode(inode);
2971
2972         /*
2973          * We only get here once per ephemeral inode.  The inode has
2974          * been initialized via inode_alloc_security but is otherwise
2975          * untouched.
2976          */
2977
2978         if (context_inode) {
2979                 struct inode_security_struct *context_isec =
2980                         selinux_inode(context_inode);
2981                 if (context_isec->initialized != LABEL_INITIALIZED) {
2982                         pr_err("SELinux:  context_inode is not initialized\n");
2983                         return -EACCES;
2984                 }
2985
2986                 isec->sclass = context_isec->sclass;
2987                 isec->sid = context_isec->sid;
2988         } else {
2989                 isec->sclass = SECCLASS_ANON_INODE;
2990                 rc = security_transition_sid(
2991                         sid, sid,
2992                         isec->sclass, name, &isec->sid);
2993                 if (rc)
2994                         return rc;
2995         }
2996
2997         isec->initialized = LABEL_INITIALIZED;
2998         /*
2999          * Now that we've initialized security, check whether we're
3000          * allowed to actually create this type of anonymous inode.
3001          */
3002
3003         ad.type = LSM_AUDIT_DATA_ANONINODE;
3004         ad.u.anonclass = name ? (const char *)name->name : "?";
3005
3006         return avc_has_perm(sid,
3007                             isec->sid,
3008                             isec->sclass,
3009                             FILE__CREATE,
3010                             &ad);
3011 }
3012
3013 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3014 {
3015         return may_create(dir, dentry, SECCLASS_FILE);
3016 }
3017
3018 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3019 {
3020         return may_link(dir, old_dentry, MAY_LINK);
3021 }
3022
3023 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3024 {
3025         return may_link(dir, dentry, MAY_UNLINK);
3026 }
3027
3028 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3029 {
3030         return may_create(dir, dentry, SECCLASS_LNK_FILE);
3031 }
3032
3033 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3034 {
3035         return may_create(dir, dentry, SECCLASS_DIR);
3036 }
3037
3038 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3039 {
3040         return may_link(dir, dentry, MAY_RMDIR);
3041 }
3042
3043 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3044 {
3045         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3046 }
3047
3048 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3049                                 struct inode *new_inode, struct dentry *new_dentry)
3050 {
3051         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3052 }
3053
3054 static int selinux_inode_readlink(struct dentry *dentry)
3055 {
3056         const struct cred *cred = current_cred();
3057
3058         return dentry_has_perm(cred, dentry, FILE__READ);
3059 }
3060
3061 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3062                                      bool rcu)
3063 {
3064         struct common_audit_data ad;
3065         struct inode_security_struct *isec;
3066         u32 sid = current_sid();
3067
3068         ad.type = LSM_AUDIT_DATA_DENTRY;
3069         ad.u.dentry = dentry;
3070         isec = inode_security_rcu(inode, rcu);
3071         if (IS_ERR(isec))
3072                 return PTR_ERR(isec);
3073
3074         return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3075 }
3076
3077 static noinline int audit_inode_permission(struct inode *inode,
3078                                            u32 perms, u32 audited, u32 denied,
3079                                            int result)
3080 {
3081         struct common_audit_data ad;
3082         struct inode_security_struct *isec = selinux_inode(inode);
3083
3084         ad.type = LSM_AUDIT_DATA_INODE;
3085         ad.u.inode = inode;
3086
3087         return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3088                             audited, denied, result, &ad);
3089 }
3090
3091 static int selinux_inode_permission(struct inode *inode, int mask)
3092 {
3093         u32 perms;
3094         bool from_access;
3095         bool no_block = mask & MAY_NOT_BLOCK;
3096         struct inode_security_struct *isec;
3097         u32 sid = current_sid();
3098         struct av_decision avd;
3099         int rc, rc2;
3100         u32 audited, denied;
3101
3102         from_access = mask & MAY_ACCESS;
3103         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3104
3105         /* No permission to check.  Existence test. */
3106         if (!mask)
3107                 return 0;
3108
3109         if (unlikely(IS_PRIVATE(inode)))
3110                 return 0;
3111
3112         perms = file_mask_to_av(inode->i_mode, mask);
3113
3114         isec = inode_security_rcu(inode, no_block);
3115         if (IS_ERR(isec))
3116                 return PTR_ERR(isec);
3117
3118         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3119                                   &avd);
3120         audited = avc_audit_required(perms, &avd, rc,
3121                                      from_access ? FILE__AUDIT_ACCESS : 0,
3122                                      &denied);
3123         if (likely(!audited))
3124                 return rc;
3125
3126         rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3127         if (rc2)
3128                 return rc2;
3129         return rc;
3130 }
3131
3132 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
3133                                  struct iattr *iattr)
3134 {
3135         const struct cred *cred = current_cred();
3136         struct inode *inode = d_backing_inode(dentry);
3137         unsigned int ia_valid = iattr->ia_valid;
3138         u32 av = FILE__WRITE;
3139
3140         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3141         if (ia_valid & ATTR_FORCE) {
3142                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3143                               ATTR_FORCE);
3144                 if (!ia_valid)
3145                         return 0;
3146         }
3147
3148         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3149                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3150                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3151
3152         if (selinux_policycap_openperm() &&
3153             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3154             (ia_valid & ATTR_SIZE) &&
3155             !(ia_valid & ATTR_FILE))
3156                 av |= FILE__OPEN;
3157
3158         return dentry_has_perm(cred, dentry, av);
3159 }
3160
3161 static int selinux_inode_getattr(const struct path *path)
3162 {
3163         return path_has_perm(current_cred(), path, FILE__GETATTR);
3164 }
3165
3166 static bool has_cap_mac_admin(bool audit)
3167 {
3168         const struct cred *cred = current_cred();
3169         unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3170
3171         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3172                 return false;
3173         if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3174                 return false;
3175         return true;
3176 }
3177
3178 /**
3179  * selinux_inode_xattr_skipcap - Skip the xattr capability checks?
3180  * @name: name of the xattr
3181  *
3182  * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs
3183  * named @name; the LSM layer should avoid enforcing any traditional
3184  * capability based access controls on this xattr.  Returns 0 to indicate that
3185  * SELinux does not "own" the access control rights to xattrs named @name and is
3186  * deferring to the LSM layer for further access controls, including capability
3187  * based controls.
3188  */
3189 static int selinux_inode_xattr_skipcap(const char *name)
3190 {
3191         /* require capability check if not a selinux xattr */
3192         return !strcmp(name, XATTR_NAME_SELINUX);
3193 }
3194
3195 static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3196                                   struct dentry *dentry, const char *name,
3197                                   const void *value, size_t size, int flags)
3198 {
3199         struct inode *inode = d_backing_inode(dentry);
3200         struct inode_security_struct *isec;
3201         struct superblock_security_struct *sbsec;
3202         struct common_audit_data ad;
3203         u32 newsid, sid = current_sid();
3204         int rc = 0;
3205
3206         /* if not a selinux xattr, only check the ordinary setattr perm */
3207         if (strcmp(name, XATTR_NAME_SELINUX))
3208                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3209
3210         if (!selinux_initialized())
3211                 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3212
3213         sbsec = selinux_superblock(inode->i_sb);
3214         if (!(sbsec->flags & SBLABEL_MNT))
3215                 return -EOPNOTSUPP;
3216
3217         if (!inode_owner_or_capable(idmap, inode))
3218                 return -EPERM;
3219
3220         ad.type = LSM_AUDIT_DATA_DENTRY;
3221         ad.u.dentry = dentry;
3222
3223         isec = backing_inode_security(dentry);
3224         rc = avc_has_perm(sid, isec->sid, isec->sclass,
3225                           FILE__RELABELFROM, &ad);
3226         if (rc)
3227                 return rc;
3228
3229         rc = security_context_to_sid(value, size, &newsid,
3230                                      GFP_KERNEL);
3231         if (rc == -EINVAL) {
3232                 if (!has_cap_mac_admin(true)) {
3233                         struct audit_buffer *ab;
3234                         size_t audit_size;
3235
3236                         /* We strip a nul only if it is at the end, otherwise the
3237                          * context contains a nul and we should audit that */
3238                         if (value) {
3239                                 const char *str = value;
3240
3241                                 if (str[size - 1] == '\0')
3242                                         audit_size = size - 1;
3243                                 else
3244                                         audit_size = size;
3245                         } else {
3246                                 audit_size = 0;
3247                         }
3248                         ab = audit_log_start(audit_context(),
3249                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3250                         if (!ab)
3251                                 return rc;
3252                         audit_log_format(ab, "op=setxattr invalid_context=");
3253                         audit_log_n_untrustedstring(ab, value, audit_size);
3254                         audit_log_end(ab);
3255
3256                         return rc;
3257                 }
3258                 rc = security_context_to_sid_force(value,
3259                                                    size, &newsid);
3260         }
3261         if (rc)
3262                 return rc;
3263
3264         rc = avc_has_perm(sid, newsid, isec->sclass,
3265                           FILE__RELABELTO, &ad);
3266         if (rc)
3267                 return rc;
3268
3269         rc = security_validate_transition(isec->sid, newsid,
3270                                           sid, isec->sclass);
3271         if (rc)
3272                 return rc;
3273
3274         return avc_has_perm(newsid,
3275                             sbsec->sid,
3276                             SECCLASS_FILESYSTEM,
3277                             FILESYSTEM__ASSOCIATE,
3278                             &ad);
3279 }
3280
3281 static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3282                                  struct dentry *dentry, const char *acl_name,
3283                                  struct posix_acl *kacl)
3284 {
3285         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3286 }
3287
3288 static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3289                                  struct dentry *dentry, const char *acl_name)
3290 {
3291         return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3292 }
3293
3294 static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3295                                     struct dentry *dentry, const char *acl_name)
3296 {
3297         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3298 }
3299
3300 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3301                                         const void *value, size_t size,
3302                                         int flags)
3303 {
3304         struct inode *inode = d_backing_inode(dentry);
3305         struct inode_security_struct *isec;
3306         u32 newsid;
3307         int rc;
3308
3309         if (strcmp(name, XATTR_NAME_SELINUX)) {
3310                 /* Not an attribute we recognize, so nothing to do. */
3311                 return;
3312         }
3313
3314         if (!selinux_initialized()) {
3315                 /* If we haven't even been initialized, then we can't validate
3316                  * against a policy, so leave the label as invalid. It may
3317                  * resolve to a valid label on the next revalidation try if
3318                  * we've since initialized.
3319                  */
3320                 return;
3321         }
3322
3323         rc = security_context_to_sid_force(value, size,
3324                                            &newsid);
3325         if (rc) {
3326                 pr_err("SELinux:  unable to map context to SID"
3327                        "for (%s, %lu), rc=%d\n",
3328                        inode->i_sb->s_id, inode->i_ino, -rc);
3329                 return;
3330         }
3331
3332         isec = backing_inode_security(dentry);
3333         spin_lock(&isec->lock);
3334         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3335         isec->sid = newsid;
3336         isec->initialized = LABEL_INITIALIZED;
3337         spin_unlock(&isec->lock);
3338 }
3339
3340 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3341 {
3342         const struct cred *cred = current_cred();
3343
3344         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3345 }
3346
3347 static int selinux_inode_listxattr(struct dentry *dentry)
3348 {
3349         const struct cred *cred = current_cred();
3350
3351         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3352 }
3353
3354 static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3355                                      struct dentry *dentry, const char *name)
3356 {
3357         /* if not a selinux xattr, only check the ordinary setattr perm */
3358         if (strcmp(name, XATTR_NAME_SELINUX))
3359                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3360
3361         if (!selinux_initialized())
3362                 return 0;
3363
3364         /* No one is allowed to remove a SELinux security label.
3365            You can change the label, but all data must be labeled. */
3366         return -EACCES;
3367 }
3368
3369 static int selinux_path_notify(const struct path *path, u64 mask,
3370                                                 unsigned int obj_type)
3371 {
3372         int ret;
3373         u32 perm;
3374
3375         struct common_audit_data ad;
3376
3377         ad.type = LSM_AUDIT_DATA_PATH;
3378         ad.u.path = *path;
3379
3380         /*
3381          * Set permission needed based on the type of mark being set.
3382          * Performs an additional check for sb watches.
3383          */
3384         switch (obj_type) {
3385         case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3386                 perm = FILE__WATCH_MOUNT;
3387                 break;
3388         case FSNOTIFY_OBJ_TYPE_SB:
3389                 perm = FILE__WATCH_SB;
3390                 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3391                                                 FILESYSTEM__WATCH, &ad);
3392                 if (ret)
3393                         return ret;
3394                 break;
3395         case FSNOTIFY_OBJ_TYPE_INODE:
3396                 perm = FILE__WATCH;
3397                 break;
3398         default:
3399                 return -EINVAL;
3400         }
3401
3402         /* blocking watches require the file:watch_with_perm permission */
3403         if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3404                 perm |= FILE__WATCH_WITH_PERM;
3405
3406         /* watches on read-like events need the file:watch_reads permission */
3407         if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_PRE_ACCESS |
3408                     FS_CLOSE_NOWRITE))
3409                 perm |= FILE__WATCH_READS;
3410
3411         return path_has_perm(current_cred(), path, perm);
3412 }
3413
3414 /*
3415  * Copy the inode security context value to the user.
3416  *
3417  * Permission check is handled by selinux_inode_getxattr hook.
3418  */
3419 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3420                                      struct inode *inode, const char *name,
3421                                      void **buffer, bool alloc)
3422 {
3423         u32 size;
3424         int error;
3425         char *context = NULL;
3426         struct inode_security_struct *isec;
3427
3428         /*
3429          * If we're not initialized yet, then we can't validate contexts, so
3430          * just let vfs_getxattr fall back to using the on-disk xattr.
3431          */
3432         if (!selinux_initialized() ||
3433             strcmp(name, XATTR_SELINUX_SUFFIX))
3434                 return -EOPNOTSUPP;
3435
3436         /*
3437          * If the caller has CAP_MAC_ADMIN, then get the raw context
3438          * value even if it is not defined by current policy; otherwise,
3439          * use the in-core value under current policy.
3440          * Use the non-auditing forms of the permission checks since
3441          * getxattr may be called by unprivileged processes commonly
3442          * and lack of permission just means that we fall back to the
3443          * in-core context value, not a denial.
3444          */
3445         isec = inode_security(inode);
3446         if (has_cap_mac_admin(false))
3447                 error = security_sid_to_context_force(isec->sid, &context,
3448                                                       &size);
3449         else
3450                 error = security_sid_to_context(isec->sid,
3451                                                 &context, &size);
3452         if (error)
3453                 return error;
3454         error = size;
3455         if (alloc) {
3456                 *buffer = context;
3457                 goto out_nofree;
3458         }
3459         kfree(context);
3460 out_nofree:
3461         return error;
3462 }
3463
3464 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3465                                      const void *value, size_t size, int flags)
3466 {
3467         struct inode_security_struct *isec = inode_security_novalidate(inode);
3468         struct superblock_security_struct *sbsec;
3469         u32 newsid;
3470         int rc;
3471
3472         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3473                 return -EOPNOTSUPP;
3474
3475         sbsec = selinux_superblock(inode->i_sb);
3476         if (!(sbsec->flags & SBLABEL_MNT))
3477                 return -EOPNOTSUPP;
3478
3479         if (!value || !size)
3480                 return -EACCES;
3481
3482         rc = security_context_to_sid(value, size, &newsid,
3483                                      GFP_KERNEL);
3484         if (rc)
3485                 return rc;
3486
3487         spin_lock(&isec->lock);
3488         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3489         isec->sid = newsid;
3490         isec->initialized = LABEL_INITIALIZED;
3491         spin_unlock(&isec->lock);
3492         return 0;
3493 }
3494
3495 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3496 {
3497         const int len = sizeof(XATTR_NAME_SELINUX);
3498
3499         if (!selinux_initialized())
3500                 return 0;
3501
3502         if (buffer && len <= buffer_size)
3503                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3504         return len;
3505 }
3506
3507 static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
3508 {
3509         struct inode_security_struct *isec = inode_security_novalidate(inode);
3510
3511         prop->selinux.secid = isec->sid;
3512 }
3513
3514 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3515 {
3516         struct lsm_prop prop;
3517         struct task_security_struct *tsec;
3518         struct cred *new_creds = *new;
3519
3520         if (new_creds == NULL) {
3521                 new_creds = prepare_creds();
3522                 if (!new_creds)
3523                         return -ENOMEM;
3524         }
3525
3526         tsec = selinux_cred(new_creds);
3527         /* Get label from overlay inode and set it in create_sid */
3528         selinux_inode_getlsmprop(d_inode(src), &prop);
3529         tsec->create_sid = prop.selinux.secid;
3530         *new = new_creds;
3531         return 0;
3532 }
3533
3534 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name)
3535 {
3536         /* The copy_up hook above sets the initial context on an inode, but we
3537          * don't then want to overwrite it by blindly copying all the lower
3538          * xattrs up.  Instead, filter out SELinux-related xattrs following
3539          * policy load.
3540          */
3541         if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX))
3542                 return -ECANCELED; /* Discard */
3543         /*
3544          * Any other attribute apart from SELINUX is not claimed, supported
3545          * by selinux.
3546          */
3547         return -EOPNOTSUPP;
3548 }
3549
3550 /* kernfs node operations */
3551
3552 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3553                                         struct kernfs_node *kn)
3554 {
3555         const struct task_security_struct *tsec = selinux_cred(current_cred());
3556         u32 parent_sid, newsid, clen;
3557         int rc;
3558         char *context;
3559
3560         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3561         if (rc == -ENODATA)
3562                 return 0;
3563         else if (rc < 0)
3564                 return rc;
3565
3566         clen = (u32)rc;
3567         context = kmalloc(clen, GFP_KERNEL);
3568         if (!context)
3569                 return -ENOMEM;
3570
3571         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3572         if (rc < 0) {
3573                 kfree(context);
3574                 return rc;
3575         }
3576
3577         rc = security_context_to_sid(context, clen, &parent_sid,
3578                                      GFP_KERNEL);
3579         kfree(context);
3580         if (rc)
3581                 return rc;
3582
3583         if (tsec->create_sid) {
3584                 newsid = tsec->create_sid;
3585         } else {
3586                 u16 secclass = inode_mode_to_security_class(kn->mode);
3587                 struct qstr q;
3588
3589                 q.name = kn->name;
3590                 q.hash_len = hashlen_string(kn_dir, kn->name);
3591
3592                 rc = security_transition_sid(tsec->sid,
3593                                              parent_sid, secclass, &q,
3594                                              &newsid);
3595                 if (rc)
3596                         return rc;
3597         }
3598
3599         rc = security_sid_to_context_force(newsid,
3600                                            &context, &clen);
3601         if (rc)
3602                 return rc;
3603
3604         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3605                               XATTR_CREATE);
3606         kfree(context);
3607         return rc;
3608 }
3609
3610
3611 /* file security operations */
3612
3613 static int selinux_revalidate_file_permission(struct file *file, int mask)
3614 {
3615         const struct cred *cred = current_cred();
3616         struct inode *inode = file_inode(file);
3617
3618         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3619         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3620                 mask |= MAY_APPEND;
3621
3622         return file_has_perm(cred, file,
3623                              file_mask_to_av(inode->i_mode, mask));
3624 }
3625
3626 static int selinux_file_permission(struct file *file, int mask)
3627 {
3628         struct inode *inode = file_inode(file);
3629         struct file_security_struct *fsec = selinux_file(file);
3630         struct inode_security_struct *isec;
3631         u32 sid = current_sid();
3632
3633         if (!mask)
3634                 /* No permission to check.  Existence test. */
3635                 return 0;
3636
3637         isec = inode_security(inode);
3638         if (sid == fsec->sid && fsec->isid == isec->sid &&
3639             fsec->pseqno == avc_policy_seqno())
3640                 /* No change since file_open check. */
3641                 return 0;
3642
3643         return selinux_revalidate_file_permission(file, mask);
3644 }
3645
3646 static int selinux_file_alloc_security(struct file *file)
3647 {
3648         struct file_security_struct *fsec = selinux_file(file);
3649         u32 sid = current_sid();
3650
3651         fsec->sid = sid;
3652         fsec->fown_sid = sid;
3653
3654         return 0;
3655 }
3656
3657 /*
3658  * Check whether a task has the ioctl permission and cmd
3659  * operation to an inode.
3660  */
3661 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3662                 u32 requested, u16 cmd)
3663 {
3664         struct common_audit_data ad;
3665         struct file_security_struct *fsec = selinux_file(file);
3666         struct inode *inode = file_inode(file);
3667         struct inode_security_struct *isec;
3668         struct lsm_ioctlop_audit ioctl;
3669         u32 ssid = cred_sid(cred);
3670         int rc;
3671         u8 driver = cmd >> 8;
3672         u8 xperm = cmd & 0xff;
3673
3674         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3675         ad.u.op = &ioctl;
3676         ad.u.op->cmd = cmd;
3677         ad.u.op->path = file->f_path;
3678
3679         if (ssid != fsec->sid) {
3680                 rc = avc_has_perm(ssid, fsec->sid,
3681                                 SECCLASS_FD,
3682                                 FD__USE,
3683                                 &ad);
3684                 if (rc)
3685                         goto out;
3686         }
3687
3688         if (unlikely(IS_PRIVATE(inode)))
3689                 return 0;
3690
3691         isec = inode_security(inode);
3692         rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, requested,
3693                                     driver, AVC_EXT_IOCTL, xperm, &ad);
3694 out:
3695         return rc;
3696 }
3697
3698 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3699                               unsigned long arg)
3700 {
3701         const struct cred *cred = current_cred();
3702         int error = 0;
3703
3704         switch (cmd) {
3705         case FIONREAD:
3706         case FIBMAP:
3707         case FIGETBSZ:
3708         case FS_IOC_GETFLAGS:
3709         case FS_IOC_GETVERSION:
3710                 error = file_has_perm(cred, file, FILE__GETATTR);
3711                 break;
3712
3713         case FS_IOC_SETFLAGS:
3714         case FS_IOC_SETVERSION:
3715                 error = file_has_perm(cred, file, FILE__SETATTR);
3716                 break;
3717
3718         /* sys_ioctl() checks */
3719         case FIONBIO:
3720         case FIOASYNC:
3721                 error = file_has_perm(cred, file, 0);
3722                 break;
3723
3724         case KDSKBENT:
3725         case KDSKBSENT:
3726                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3727                                             CAP_OPT_NONE, true);
3728                 break;
3729
3730         case FIOCLEX:
3731         case FIONCLEX:
3732                 if (!selinux_policycap_ioctl_skip_cloexec())
3733                         error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3734                 break;
3735
3736         /* default case assumes that the command will go
3737          * to the file's ioctl() function.
3738          */
3739         default:
3740                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3741         }
3742         return error;
3743 }
3744
3745 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3746                               unsigned long arg)
3747 {
3748         /*
3749          * If we are in a 64-bit kernel running 32-bit userspace, we need to
3750          * make sure we don't compare 32-bit flags to 64-bit flags.
3751          */
3752         switch (cmd) {
3753         case FS_IOC32_GETFLAGS:
3754                 cmd = FS_IOC_GETFLAGS;
3755                 break;
3756         case FS_IOC32_SETFLAGS:
3757                 cmd = FS_IOC_SETFLAGS;
3758                 break;
3759         case FS_IOC32_GETVERSION:
3760                 cmd = FS_IOC_GETVERSION;
3761                 break;
3762         case FS_IOC32_SETVERSION:
3763                 cmd = FS_IOC_SETVERSION;
3764                 break;
3765         default:
3766                 break;
3767         }
3768
3769         return selinux_file_ioctl(file, cmd, arg);
3770 }
3771
3772 static int default_noexec __ro_after_init;
3773
3774 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3775 {
3776         const struct cred *cred = current_cred();
3777         u32 sid = cred_sid(cred);
3778         int rc = 0;
3779
3780         if (default_noexec &&
3781             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3782                                    (!shared && (prot & PROT_WRITE)))) {
3783                 /*
3784                  * We are making executable an anonymous mapping or a
3785                  * private file mapping that will also be writable.
3786                  * This has an additional check.
3787                  */
3788                 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3789                                   PROCESS__EXECMEM, NULL);
3790                 if (rc)
3791                         goto error;
3792         }
3793
3794         if (file) {
3795                 /* read access is always possible with a mapping */
3796                 u32 av = FILE__READ;
3797
3798                 /* write access only matters if the mapping is shared */
3799                 if (shared && (prot & PROT_WRITE))
3800                         av |= FILE__WRITE;
3801
3802                 if (prot & PROT_EXEC)
3803                         av |= FILE__EXECUTE;
3804
3805                 return file_has_perm(cred, file, av);
3806         }
3807
3808 error:
3809         return rc;
3810 }
3811
3812 static int selinux_mmap_addr(unsigned long addr)
3813 {
3814         int rc = 0;
3815
3816         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3817                 u32 sid = current_sid();
3818                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3819                                   MEMPROTECT__MMAP_ZERO, NULL);
3820         }
3821
3822         return rc;
3823 }
3824
3825 static int selinux_mmap_file(struct file *file,
3826                              unsigned long reqprot __always_unused,
3827                              unsigned long prot, unsigned long flags)
3828 {
3829         struct common_audit_data ad;
3830         int rc;
3831
3832         if (file) {
3833                 ad.type = LSM_AUDIT_DATA_FILE;
3834                 ad.u.file = file;
3835                 rc = inode_has_perm(current_cred(), file_inode(file),
3836                                     FILE__MAP, &ad);
3837                 if (rc)
3838                         return rc;
3839         }
3840
3841         return file_map_prot_check(file, prot,
3842                                    (flags & MAP_TYPE) == MAP_SHARED);
3843 }
3844
3845 static int selinux_file_mprotect(struct vm_area_struct *vma,
3846                                  unsigned long reqprot __always_unused,
3847                                  unsigned long prot)
3848 {
3849         const struct cred *cred = current_cred();
3850         u32 sid = cred_sid(cred);
3851
3852         if (default_noexec &&
3853             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3854                 int rc = 0;
3855                 /*
3856                  * We don't use the vma_is_initial_heap() helper as it has
3857                  * a history of problems and is currently broken on systems
3858                  * where there is no heap, e.g. brk == start_brk.  Before
3859                  * replacing the conditional below with vma_is_initial_heap(),
3860                  * or something similar, please ensure that the logic is the
3861                  * same as what we have below or you have tested every possible
3862                  * corner case you can think to test.
3863                  */
3864                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3865                     vma->vm_end <= vma->vm_mm->brk) {
3866                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3867                                           PROCESS__EXECHEAP, NULL);
3868                 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3869                             vma_is_stack_for_current(vma))) {
3870                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3871                                           PROCESS__EXECSTACK, NULL);
3872                 } else if (vma->vm_file && vma->anon_vma) {
3873                         /*
3874                          * We are making executable a file mapping that has
3875                          * had some COW done. Since pages might have been
3876                          * written, check ability to execute the possibly
3877                          * modified content.  This typically should only
3878                          * occur for text relocations.
3879                          */
3880                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3881                 }
3882                 if (rc)
3883                         return rc;
3884         }
3885
3886         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3887 }
3888
3889 static int selinux_file_lock(struct file *file, unsigned int cmd)
3890 {
3891         const struct cred *cred = current_cred();
3892
3893         return file_has_perm(cred, file, FILE__LOCK);
3894 }
3895
3896 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3897                               unsigned long arg)
3898 {
3899         const struct cred *cred = current_cred();
3900         int err = 0;
3901
3902         switch (cmd) {
3903         case F_SETFL:
3904                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3905                         err = file_has_perm(cred, file, FILE__WRITE);
3906                         break;
3907                 }
3908                 fallthrough;
3909         case F_SETOWN:
3910         case F_SETSIG:
3911         case F_GETFL:
3912         case F_GETOWN:
3913         case F_GETSIG:
3914         case F_GETOWNER_UIDS:
3915                 /* Just check FD__USE permission */
3916                 err = file_has_perm(cred, file, 0);
3917                 break;
3918         case F_GETLK:
3919         case F_SETLK:
3920         case F_SETLKW:
3921         case F_OFD_GETLK:
3922         case F_OFD_SETLK:
3923         case F_OFD_SETLKW:
3924 #if BITS_PER_LONG == 32
3925         case F_GETLK64:
3926         case F_SETLK64:
3927         case F_SETLKW64:
3928 #endif
3929                 err = file_has_perm(cred, file, FILE__LOCK);
3930                 break;
3931         }
3932
3933         return err;
3934 }
3935
3936 static void selinux_file_set_fowner(struct file *file)
3937 {
3938         struct file_security_struct *fsec;
3939
3940         fsec = selinux_file(file);
3941         fsec->fown_sid = current_sid();
3942 }
3943
3944 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3945                                        struct fown_struct *fown, int signum)
3946 {
3947         struct file *file;
3948         u32 sid = task_sid_obj(tsk);
3949         u32 perm;
3950         struct file_security_struct *fsec;
3951
3952         /* struct fown_struct is never outside the context of a struct file */
3953         file = fown->file;
3954
3955         fsec = selinux_file(file);
3956
3957         if (!signum)
3958                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3959         else
3960                 perm = signal_to_av(signum);
3961
3962         return avc_has_perm(fsec->fown_sid, sid,
3963                             SECCLASS_PROCESS, perm, NULL);
3964 }
3965
3966 static int selinux_file_receive(struct file *file)
3967 {
3968         const struct cred *cred = current_cred();
3969
3970         return file_has_perm(cred, file, file_to_av(file));
3971 }
3972
3973 static int selinux_file_open(struct file *file)
3974 {
3975         struct file_security_struct *fsec;
3976         struct inode_security_struct *isec;
3977
3978         fsec = selinux_file(file);
3979         isec = inode_security(file_inode(file));
3980         /*
3981          * Save inode label and policy sequence number
3982          * at open-time so that selinux_file_permission
3983          * can determine whether revalidation is necessary.
3984          * Task label is already saved in the file security
3985          * struct as its SID.
3986          */
3987         fsec->isid = isec->sid;
3988         fsec->pseqno = avc_policy_seqno();
3989         /*
3990          * Since the inode label or policy seqno may have changed
3991          * between the selinux_inode_permission check and the saving
3992          * of state above, recheck that access is still permitted.
3993          * Otherwise, access might never be revalidated against the
3994          * new inode label or new policy.
3995          * This check is not redundant - do not remove.
3996          */
3997         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3998 }
3999
4000 /* task security operations */
4001
4002 static int selinux_task_alloc(struct task_struct *task,
4003                               unsigned long clone_flags)
4004 {
4005         u32 sid = current_sid();
4006
4007         return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4008 }
4009
4010 /*
4011  * prepare a new set of credentials for modification
4012  */
4013 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4014                                 gfp_t gfp)
4015 {
4016         const struct task_security_struct *old_tsec = selinux_cred(old);
4017         struct task_security_struct *tsec = selinux_cred(new);
4018
4019         *tsec = *old_tsec;
4020         return 0;
4021 }
4022
4023 /*
4024  * transfer the SELinux data to a blank set of creds
4025  */
4026 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4027 {
4028         const struct task_security_struct *old_tsec = selinux_cred(old);
4029         struct task_security_struct *tsec = selinux_cred(new);
4030
4031         *tsec = *old_tsec;
4032 }
4033
4034 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4035 {
4036         *secid = cred_sid(c);
4037 }
4038
4039 static void selinux_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
4040 {
4041         prop->selinux.secid = cred_sid(c);
4042 }
4043
4044 /*
4045  * set the security data for a kernel service
4046  * - all the creation contexts are set to unlabelled
4047  */
4048 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4049 {
4050         struct task_security_struct *tsec = selinux_cred(new);
4051         u32 sid = current_sid();
4052         int ret;
4053
4054         ret = avc_has_perm(sid, secid,
4055                            SECCLASS_KERNEL_SERVICE,
4056                            KERNEL_SERVICE__USE_AS_OVERRIDE,
4057                            NULL);
4058         if (ret == 0) {
4059                 tsec->sid = secid;
4060                 tsec->create_sid = 0;
4061                 tsec->keycreate_sid = 0;
4062                 tsec->sockcreate_sid = 0;
4063         }
4064         return ret;
4065 }
4066
4067 /*
4068  * set the file creation context in a security record to the same as the
4069  * objective context of the specified inode
4070  */
4071 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4072 {
4073         struct inode_security_struct *isec = inode_security(inode);
4074         struct task_security_struct *tsec = selinux_cred(new);
4075         u32 sid = current_sid();
4076         int ret;
4077
4078         ret = avc_has_perm(sid, isec->sid,
4079                            SECCLASS_KERNEL_SERVICE,
4080                            KERNEL_SERVICE__CREATE_FILES_AS,
4081                            NULL);
4082
4083         if (ret == 0)
4084                 tsec->create_sid = isec->sid;
4085         return ret;
4086 }
4087
4088 static int selinux_kernel_module_request(char *kmod_name)
4089 {
4090         struct common_audit_data ad;
4091
4092         ad.type = LSM_AUDIT_DATA_KMOD;
4093         ad.u.kmod_name = kmod_name;
4094
4095         return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4096                             SYSTEM__MODULE_REQUEST, &ad);
4097 }
4098
4099 static int selinux_kernel_module_from_file(struct file *file)
4100 {
4101         struct common_audit_data ad;
4102         struct inode_security_struct *isec;
4103         struct file_security_struct *fsec;
4104         u32 sid = current_sid();
4105         int rc;
4106
4107         /* init_module */
4108         if (file == NULL)
4109                 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4110                                         SYSTEM__MODULE_LOAD, NULL);
4111
4112         /* finit_module */
4113
4114         ad.type = LSM_AUDIT_DATA_FILE;
4115         ad.u.file = file;
4116
4117         fsec = selinux_file(file);
4118         if (sid != fsec->sid) {
4119                 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4120                 if (rc)
4121                         return rc;
4122         }
4123
4124         isec = inode_security(file_inode(file));
4125         return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4126                                 SYSTEM__MODULE_LOAD, &ad);
4127 }
4128
4129 static int selinux_kernel_read_file(struct file *file,
4130                                     enum kernel_read_file_id id,
4131                                     bool contents)
4132 {
4133         int rc = 0;
4134
4135         switch (id) {
4136         case READING_MODULE:
4137                 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4138                 break;
4139         default:
4140                 break;
4141         }
4142
4143         return rc;
4144 }
4145
4146 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4147 {
4148         int rc = 0;
4149
4150         switch (id) {
4151         case LOADING_MODULE:
4152                 rc = selinux_kernel_module_from_file(NULL);
4153                 break;
4154         default:
4155                 break;
4156         }
4157
4158         return rc;
4159 }
4160
4161 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4162 {
4163         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4164                             PROCESS__SETPGID, NULL);
4165 }
4166
4167 static int selinux_task_getpgid(struct task_struct *p)
4168 {
4169         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4170                             PROCESS__GETPGID, NULL);
4171 }
4172
4173 static int selinux_task_getsid(struct task_struct *p)
4174 {
4175         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4176                             PROCESS__GETSESSION, NULL);
4177 }
4178
4179 static void selinux_current_getlsmprop_subj(struct lsm_prop *prop)
4180 {
4181         prop->selinux.secid = current_sid();
4182 }
4183
4184 static void selinux_task_getlsmprop_obj(struct task_struct *p,
4185                                         struct lsm_prop *prop)
4186 {
4187         prop->selinux.secid = task_sid_obj(p);
4188 }
4189
4190 static int selinux_task_setnice(struct task_struct *p, int nice)
4191 {
4192         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4193                             PROCESS__SETSCHED, NULL);
4194 }
4195
4196 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4197 {
4198         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4199                             PROCESS__SETSCHED, NULL);
4200 }
4201
4202 static int selinux_task_getioprio(struct task_struct *p)
4203 {
4204         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4205                             PROCESS__GETSCHED, NULL);
4206 }
4207
4208 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4209                                 unsigned int flags)
4210 {
4211         u32 av = 0;
4212
4213         if (!flags)
4214                 return 0;
4215         if (flags & LSM_PRLIMIT_WRITE)
4216                 av |= PROCESS__SETRLIMIT;
4217         if (flags & LSM_PRLIMIT_READ)
4218                 av |= PROCESS__GETRLIMIT;
4219         return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4220                             SECCLASS_PROCESS, av, NULL);
4221 }
4222
4223 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4224                 struct rlimit *new_rlim)
4225 {
4226         struct rlimit *old_rlim = p->signal->rlim + resource;
4227
4228         /* Control the ability to change the hard limit (whether
4229            lowering or raising it), so that the hard limit can
4230            later be used as a safe reset point for the soft limit
4231            upon context transitions.  See selinux_bprm_committing_creds. */
4232         if (old_rlim->rlim_max != new_rlim->rlim_max)
4233                 return avc_has_perm(current_sid(), task_sid_obj(p),
4234                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4235
4236         return 0;
4237 }
4238
4239 static int selinux_task_setscheduler(struct task_struct *p)
4240 {
4241         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4242                             PROCESS__SETSCHED, NULL);
4243 }
4244
4245 static int selinux_task_getscheduler(struct task_struct *p)
4246 {
4247         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4248                             PROCESS__GETSCHED, NULL);
4249 }
4250
4251 static int selinux_task_movememory(struct task_struct *p)
4252 {
4253         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4254                             PROCESS__SETSCHED, NULL);
4255 }
4256
4257 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4258                                 int sig, const struct cred *cred)
4259 {
4260         u32 secid;
4261         u32 perm;
4262
4263         if (!sig)
4264                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4265         else
4266                 perm = signal_to_av(sig);
4267         if (!cred)
4268                 secid = current_sid();
4269         else
4270                 secid = cred_sid(cred);
4271         return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4272 }
4273
4274 static void selinux_task_to_inode(struct task_struct *p,
4275                                   struct inode *inode)
4276 {
4277         struct inode_security_struct *isec = selinux_inode(inode);
4278         u32 sid = task_sid_obj(p);
4279
4280         spin_lock(&isec->lock);
4281         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4282         isec->sid = sid;
4283         isec->initialized = LABEL_INITIALIZED;
4284         spin_unlock(&isec->lock);
4285 }
4286
4287 static int selinux_userns_create(const struct cred *cred)
4288 {
4289         u32 sid = current_sid();
4290
4291         return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4292                         USER_NAMESPACE__CREATE, NULL);
4293 }
4294
4295 /* Returns error only if unable to parse addresses */
4296 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4297                         struct common_audit_data *ad, u8 *proto)
4298 {
4299         int offset, ihlen, ret = -EINVAL;
4300         struct iphdr _iph, *ih;
4301
4302         offset = skb_network_offset(skb);
4303         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4304         if (ih == NULL)
4305                 goto out;
4306
4307         ihlen = ih->ihl * 4;
4308         if (ihlen < sizeof(_iph))
4309                 goto out;
4310
4311         ad->u.net->v4info.saddr = ih->saddr;
4312         ad->u.net->v4info.daddr = ih->daddr;
4313         ret = 0;
4314
4315         if (proto)
4316                 *proto = ih->protocol;
4317
4318         switch (ih->protocol) {
4319         case IPPROTO_TCP: {
4320                 struct tcphdr _tcph, *th;
4321
4322                 if (ntohs(ih->frag_off) & IP_OFFSET)
4323                         break;
4324
4325                 offset += ihlen;
4326                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4327                 if (th == NULL)
4328                         break;
4329
4330                 ad->u.net->sport = th->source;
4331                 ad->u.net->dport = th->dest;
4332                 break;
4333         }
4334
4335         case IPPROTO_UDP: {
4336                 struct udphdr _udph, *uh;
4337
4338                 if (ntohs(ih->frag_off) & IP_OFFSET)
4339                         break;
4340
4341                 offset += ihlen;
4342                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4343                 if (uh == NULL)
4344                         break;
4345
4346                 ad->u.net->sport = uh->source;
4347                 ad->u.net->dport = uh->dest;
4348                 break;
4349         }
4350
4351         case IPPROTO_DCCP: {
4352                 struct dccp_hdr _dccph, *dh;
4353
4354                 if (ntohs(ih->frag_off) & IP_OFFSET)
4355                         break;
4356
4357                 offset += ihlen;
4358                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4359                 if (dh == NULL)
4360                         break;
4361
4362                 ad->u.net->sport = dh->dccph_sport;
4363                 ad->u.net->dport = dh->dccph_dport;
4364                 break;
4365         }
4366
4367 #if IS_ENABLED(CONFIG_IP_SCTP)
4368         case IPPROTO_SCTP: {
4369                 struct sctphdr _sctph, *sh;
4370
4371                 if (ntohs(ih->frag_off) & IP_OFFSET)
4372                         break;
4373
4374                 offset += ihlen;
4375                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4376                 if (sh == NULL)
4377                         break;
4378
4379                 ad->u.net->sport = sh->source;
4380                 ad->u.net->dport = sh->dest;
4381                 break;
4382         }
4383 #endif
4384         default:
4385                 break;
4386         }
4387 out:
4388         return ret;
4389 }
4390
4391 #if IS_ENABLED(CONFIG_IPV6)
4392
4393 /* Returns error only if unable to parse addresses */
4394 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4395                         struct common_audit_data *ad, u8 *proto)
4396 {
4397         u8 nexthdr;
4398         int ret = -EINVAL, offset;
4399         struct ipv6hdr _ipv6h, *ip6;
4400         __be16 frag_off;
4401
4402         offset = skb_network_offset(skb);
4403         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4404         if (ip6 == NULL)
4405                 goto out;
4406
4407         ad->u.net->v6info.saddr = ip6->saddr;
4408         ad->u.net->v6info.daddr = ip6->daddr;
4409         ret = 0;
4410
4411         nexthdr = ip6->nexthdr;
4412         offset += sizeof(_ipv6h);
4413         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4414         if (offset < 0)
4415                 goto out;
4416
4417         if (proto)
4418                 *proto = nexthdr;
4419
4420         switch (nexthdr) {
4421         case IPPROTO_TCP: {
4422                 struct tcphdr _tcph, *th;
4423
4424                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4425                 if (th == NULL)
4426                         break;
4427
4428                 ad->u.net->sport = th->source;
4429                 ad->u.net->dport = th->dest;
4430                 break;
4431         }
4432
4433         case IPPROTO_UDP: {
4434                 struct udphdr _udph, *uh;
4435
4436                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4437                 if (uh == NULL)
4438                         break;
4439
4440                 ad->u.net->sport = uh->source;
4441                 ad->u.net->dport = uh->dest;
4442                 break;
4443         }
4444
4445         case IPPROTO_DCCP: {
4446                 struct dccp_hdr _dccph, *dh;
4447
4448                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4449                 if (dh == NULL)
4450                         break;
4451
4452                 ad->u.net->sport = dh->dccph_sport;
4453                 ad->u.net->dport = dh->dccph_dport;
4454                 break;
4455         }
4456
4457 #if IS_ENABLED(CONFIG_IP_SCTP)
4458         case IPPROTO_SCTP: {
4459                 struct sctphdr _sctph, *sh;
4460
4461                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4462                 if (sh == NULL)
4463                         break;
4464
4465                 ad->u.net->sport = sh->source;
4466                 ad->u.net->dport = sh->dest;
4467                 break;
4468         }
4469 #endif
4470         /* includes fragments */
4471         default:
4472                 break;
4473         }
4474 out:
4475         return ret;
4476 }
4477
4478 #endif /* IPV6 */
4479
4480 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4481                              char **_addrp, int src, u8 *proto)
4482 {
4483         char *addrp;
4484         int ret;
4485
4486         switch (ad->u.net->family) {
4487         case PF_INET:
4488                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4489                 if (ret)
4490                         goto parse_error;
4491                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4492                                        &ad->u.net->v4info.daddr);
4493                 goto okay;
4494
4495 #if IS_ENABLED(CONFIG_IPV6)
4496         case PF_INET6:
4497                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4498                 if (ret)
4499                         goto parse_error;
4500                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4501                                        &ad->u.net->v6info.daddr);
4502                 goto okay;
4503 #endif  /* IPV6 */
4504         default:
4505                 addrp = NULL;
4506                 goto okay;
4507         }
4508
4509 parse_error:
4510         pr_warn(
4511                "SELinux: failure in selinux_parse_skb(),"
4512                " unable to parse packet\n");
4513         return ret;
4514
4515 okay:
4516         if (_addrp)
4517                 *_addrp = addrp;
4518         return 0;
4519 }
4520
4521 /**
4522  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4523  * @skb: the packet
4524  * @family: protocol family
4525  * @sid: the packet's peer label SID
4526  *
4527  * Description:
4528  * Check the various different forms of network peer labeling and determine
4529  * the peer label/SID for the packet; most of the magic actually occurs in
4530  * the security server function security_net_peersid_cmp().  The function
4531  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4532  * or -EACCES if @sid is invalid due to inconsistencies with the different
4533  * peer labels.
4534  *
4535  */
4536 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4537 {
4538         int err;
4539         u32 xfrm_sid;
4540         u32 nlbl_sid;
4541         u32 nlbl_type;
4542
4543         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4544         if (unlikely(err))
4545                 return -EACCES;
4546         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4547         if (unlikely(err))
4548                 return -EACCES;
4549
4550         err = security_net_peersid_resolve(nlbl_sid,
4551                                            nlbl_type, xfrm_sid, sid);
4552         if (unlikely(err)) {
4553                 pr_warn(
4554                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4555                        " unable to determine packet's peer label\n");
4556                 return -EACCES;
4557         }
4558
4559         return 0;
4560 }
4561
4562 /**
4563  * selinux_conn_sid - Determine the child socket label for a connection
4564  * @sk_sid: the parent socket's SID
4565  * @skb_sid: the packet's SID
4566  * @conn_sid: the resulting connection SID
4567  *
4568  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4569  * combined with the MLS information from @skb_sid in order to create
4570  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4571  * of @sk_sid.  Returns zero on success, negative values on failure.
4572  *
4573  */
4574 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4575 {
4576         int err = 0;
4577
4578         if (skb_sid != SECSID_NULL)
4579                 err = security_sid_mls_copy(sk_sid, skb_sid,
4580                                             conn_sid);
4581         else
4582                 *conn_sid = sk_sid;
4583
4584         return err;
4585 }
4586
4587 /* socket security operations */
4588
4589 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4590                                  u16 secclass, u32 *socksid)
4591 {
4592         if (tsec->sockcreate_sid > SECSID_NULL) {
4593                 *socksid = tsec->sockcreate_sid;
4594                 return 0;
4595         }
4596
4597         return security_transition_sid(tsec->sid, tsec->sid,
4598                                        secclass, NULL, socksid);
4599 }
4600
4601 static bool sock_skip_has_perm(u32 sid)
4602 {
4603         if (sid == SECINITSID_KERNEL)
4604                 return true;
4605
4606         /*
4607          * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4608          * inherited the kernel context from early boot used to be skipped
4609          * here, so preserve that behavior unless the capability is set.
4610          *
4611          * By setting the capability the policy signals that it is ready
4612          * for this quirk to be fixed. Note that sockets created by a kernel
4613          * thread or a usermode helper executed without a transition will
4614          * still be skipped in this check regardless of the policycap
4615          * setting.
4616          */
4617         if (!selinux_policycap_userspace_initial_context() &&
4618             sid == SECINITSID_INIT)
4619                 return true;
4620         return false;
4621 }
4622
4623
4624 static int sock_has_perm(struct sock *sk, u32 perms)
4625 {
4626         struct sk_security_struct *sksec = sk->sk_security;
4627         struct common_audit_data ad;
4628         struct lsm_network_audit net;
4629
4630         if (sock_skip_has_perm(sksec->sid))
4631                 return 0;
4632
4633         ad_net_init_from_sk(&ad, &net, sk);
4634
4635         return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4636                             &ad);
4637 }
4638
4639 static int selinux_socket_create(int family, int type,
4640                                  int protocol, int kern)
4641 {
4642         const struct task_security_struct *tsec = selinux_cred(current_cred());
4643         u32 newsid;
4644         u16 secclass;
4645         int rc;
4646
4647         if (kern)
4648                 return 0;
4649
4650         secclass = socket_type_to_security_class(family, type, protocol);
4651         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4652         if (rc)
4653                 return rc;
4654
4655         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4656 }
4657
4658 static int selinux_socket_post_create(struct socket *sock, int family,
4659                                       int type, int protocol, int kern)
4660 {
4661         const struct task_security_struct *tsec = selinux_cred(current_cred());
4662         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4663         struct sk_security_struct *sksec;
4664         u16 sclass = socket_type_to_security_class(family, type, protocol);
4665         u32 sid = SECINITSID_KERNEL;
4666         int err = 0;
4667
4668         if (!kern) {
4669                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4670                 if (err)
4671                         return err;
4672         }
4673
4674         isec->sclass = sclass;
4675         isec->sid = sid;
4676         isec->initialized = LABEL_INITIALIZED;
4677
4678         if (sock->sk) {
4679                 sksec = selinux_sock(sock->sk);
4680                 sksec->sclass = sclass;
4681                 sksec->sid = sid;
4682                 /* Allows detection of the first association on this socket */
4683                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4684                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4685
4686                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4687         }
4688
4689         return err;
4690 }
4691
4692 static int selinux_socket_socketpair(struct socket *socka,
4693                                      struct socket *sockb)
4694 {
4695         struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
4696         struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
4697
4698         sksec_a->peer_sid = sksec_b->sid;
4699         sksec_b->peer_sid = sksec_a->sid;
4700
4701         return 0;
4702 }
4703
4704 /* Range of port numbers used to automatically bind.
4705    Need to determine whether we should perform a name_bind
4706    permission check between the socket and the port number. */
4707
4708 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4709 {
4710         struct sock *sk = sock->sk;
4711         struct sk_security_struct *sksec = selinux_sock(sk);
4712         u16 family;
4713         int err;
4714
4715         err = sock_has_perm(sk, SOCKET__BIND);
4716         if (err)
4717                 goto out;
4718
4719         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4720         family = sk->sk_family;
4721         if (family == PF_INET || family == PF_INET6) {
4722                 char *addrp;
4723                 struct common_audit_data ad;
4724                 struct lsm_network_audit net = {0,};
4725                 struct sockaddr_in *addr4 = NULL;
4726                 struct sockaddr_in6 *addr6 = NULL;
4727                 u16 family_sa;
4728                 unsigned short snum;
4729                 u32 sid, node_perm;
4730
4731                 /*
4732                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4733                  * that validates multiple binding addresses. Because of this
4734                  * need to check address->sa_family as it is possible to have
4735                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4736                  */
4737                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4738                         return -EINVAL;
4739                 family_sa = address->sa_family;
4740                 switch (family_sa) {
4741                 case AF_UNSPEC:
4742                 case AF_INET:
4743                         if (addrlen < sizeof(struct sockaddr_in))
4744                                 return -EINVAL;
4745                         addr4 = (struct sockaddr_in *)address;
4746                         if (family_sa == AF_UNSPEC) {
4747                                 if (family == PF_INET6) {
4748                                         /* Length check from inet6_bind_sk() */
4749                                         if (addrlen < SIN6_LEN_RFC2133)
4750                                                 return -EINVAL;
4751                                         /* Family check from __inet6_bind() */
4752                                         goto err_af;
4753                                 }
4754                                 /* see __inet_bind(), we only want to allow
4755                                  * AF_UNSPEC if the address is INADDR_ANY
4756                                  */
4757                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4758                                         goto err_af;
4759                                 family_sa = AF_INET;
4760                         }
4761                         snum = ntohs(addr4->sin_port);
4762                         addrp = (char *)&addr4->sin_addr.s_addr;
4763                         break;
4764                 case AF_INET6:
4765                         if (addrlen < SIN6_LEN_RFC2133)
4766                                 return -EINVAL;
4767                         addr6 = (struct sockaddr_in6 *)address;
4768                         snum = ntohs(addr6->sin6_port);
4769                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4770                         break;
4771                 default:
4772                         goto err_af;
4773                 }
4774
4775                 ad.type = LSM_AUDIT_DATA_NET;
4776                 ad.u.net = &net;
4777                 ad.u.net->sport = htons(snum);
4778                 ad.u.net->family = family_sa;
4779
4780                 if (snum) {
4781                         int low, high;
4782
4783                         inet_get_local_port_range(sock_net(sk), &low, &high);
4784
4785                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4786                             snum < low || snum > high) {
4787                                 err = sel_netport_sid(sk->sk_protocol,
4788                                                       snum, &sid);
4789                                 if (err)
4790                                         goto out;
4791                                 err = avc_has_perm(sksec->sid, sid,
4792                                                    sksec->sclass,
4793                                                    SOCKET__NAME_BIND, &ad);
4794                                 if (err)
4795                                         goto out;
4796                         }
4797                 }
4798
4799                 switch (sksec->sclass) {
4800                 case SECCLASS_TCP_SOCKET:
4801                         node_perm = TCP_SOCKET__NODE_BIND;
4802                         break;
4803
4804                 case SECCLASS_UDP_SOCKET:
4805                         node_perm = UDP_SOCKET__NODE_BIND;
4806                         break;
4807
4808                 case SECCLASS_DCCP_SOCKET:
4809                         node_perm = DCCP_SOCKET__NODE_BIND;
4810                         break;
4811
4812                 case SECCLASS_SCTP_SOCKET:
4813                         node_perm = SCTP_SOCKET__NODE_BIND;
4814                         break;
4815
4816                 default:
4817                         node_perm = RAWIP_SOCKET__NODE_BIND;
4818                         break;
4819                 }
4820
4821                 err = sel_netnode_sid(addrp, family_sa, &sid);
4822                 if (err)
4823                         goto out;
4824
4825                 if (family_sa == AF_INET)
4826                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4827                 else
4828                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4829
4830                 err = avc_has_perm(sksec->sid, sid,
4831                                    sksec->sclass, node_perm, &ad);
4832                 if (err)
4833                         goto out;
4834         }
4835 out:
4836         return err;
4837 err_af:
4838         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4839         if (sk->sk_protocol == IPPROTO_SCTP)
4840                 return -EINVAL;
4841         return -EAFNOSUPPORT;
4842 }
4843
4844 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4845  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4846  */
4847 static int selinux_socket_connect_helper(struct socket *sock,
4848                                          struct sockaddr *address, int addrlen)
4849 {
4850         struct sock *sk = sock->sk;
4851         struct sk_security_struct *sksec = selinux_sock(sk);
4852         int err;
4853
4854         err = sock_has_perm(sk, SOCKET__CONNECT);
4855         if (err)
4856                 return err;
4857         if (addrlen < offsetofend(struct sockaddr, sa_family))
4858                 return -EINVAL;
4859
4860         /* connect(AF_UNSPEC) has special handling, as it is a documented
4861          * way to disconnect the socket
4862          */
4863         if (address->sa_family == AF_UNSPEC)
4864                 return 0;
4865
4866         /*
4867          * If a TCP, DCCP or SCTP socket, check name_connect permission
4868          * for the port.
4869          */
4870         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4871             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4872             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4873                 struct common_audit_data ad;
4874                 struct lsm_network_audit net = {0,};
4875                 struct sockaddr_in *addr4 = NULL;
4876                 struct sockaddr_in6 *addr6 = NULL;
4877                 unsigned short snum;
4878                 u32 sid, perm;
4879
4880                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4881                  * that validates multiple connect addresses. Because of this
4882                  * need to check address->sa_family as it is possible to have
4883                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4884                  */
4885                 switch (address->sa_family) {
4886                 case AF_INET:
4887                         addr4 = (struct sockaddr_in *)address;
4888                         if (addrlen < sizeof(struct sockaddr_in))
4889                                 return -EINVAL;
4890                         snum = ntohs(addr4->sin_port);
4891                         break;
4892                 case AF_INET6:
4893                         addr6 = (struct sockaddr_in6 *)address;
4894                         if (addrlen < SIN6_LEN_RFC2133)
4895                                 return -EINVAL;
4896                         snum = ntohs(addr6->sin6_port);
4897                         break;
4898                 default:
4899                         /* Note that SCTP services expect -EINVAL, whereas
4900                          * others expect -EAFNOSUPPORT.
4901                          */
4902                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4903                                 return -EINVAL;
4904                         else
4905                                 return -EAFNOSUPPORT;
4906                 }
4907
4908                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4909                 if (err)
4910                         return err;
4911
4912                 switch (sksec->sclass) {
4913                 case SECCLASS_TCP_SOCKET:
4914                         perm = TCP_SOCKET__NAME_CONNECT;
4915                         break;
4916                 case SECCLASS_DCCP_SOCKET:
4917                         perm = DCCP_SOCKET__NAME_CONNECT;
4918                         break;
4919                 case SECCLASS_SCTP_SOCKET:
4920                         perm = SCTP_SOCKET__NAME_CONNECT;
4921                         break;
4922                 }
4923
4924                 ad.type = LSM_AUDIT_DATA_NET;
4925                 ad.u.net = &net;
4926                 ad.u.net->dport = htons(snum);
4927                 ad.u.net->family = address->sa_family;
4928                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4929                 if (err)
4930                         return err;
4931         }
4932
4933         return 0;
4934 }
4935
4936 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4937 static int selinux_socket_connect(struct socket *sock,
4938                                   struct sockaddr *address, int addrlen)
4939 {
4940         int err;
4941         struct sock *sk = sock->sk;
4942
4943         err = selinux_socket_connect_helper(sock, address, addrlen);
4944         if (err)
4945                 return err;
4946
4947         return selinux_netlbl_socket_connect(sk, address);
4948 }
4949
4950 static int selinux_socket_listen(struct socket *sock, int backlog)
4951 {
4952         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4953 }
4954
4955 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4956 {
4957         int err;
4958         struct inode_security_struct *isec;
4959         struct inode_security_struct *newisec;
4960         u16 sclass;
4961         u32 sid;
4962
4963         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4964         if (err)
4965                 return err;
4966
4967         isec = inode_security_novalidate(SOCK_INODE(sock));
4968         spin_lock(&isec->lock);
4969         sclass = isec->sclass;
4970         sid = isec->sid;
4971         spin_unlock(&isec->lock);
4972
4973         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4974         newisec->sclass = sclass;
4975         newisec->sid = sid;
4976         newisec->initialized = LABEL_INITIALIZED;
4977
4978         return 0;
4979 }
4980
4981 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4982                                   int size)
4983 {
4984         return sock_has_perm(sock->sk, SOCKET__WRITE);
4985 }
4986
4987 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4988                                   int size, int flags)
4989 {
4990         return sock_has_perm(sock->sk, SOCKET__READ);
4991 }
4992
4993 static int selinux_socket_getsockname(struct socket *sock)
4994 {
4995         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4996 }
4997
4998 static int selinux_socket_getpeername(struct socket *sock)
4999 {
5000         return sock_has_perm(sock->sk, SOCKET__GETATTR);
5001 }
5002
5003 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5004 {
5005         int err;
5006
5007         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5008         if (err)
5009                 return err;
5010
5011         return selinux_netlbl_socket_setsockopt(sock, level, optname);
5012 }
5013
5014 static int selinux_socket_getsockopt(struct socket *sock, int level,
5015                                      int optname)
5016 {
5017         return sock_has_perm(sock->sk, SOCKET__GETOPT);
5018 }
5019
5020 static int selinux_socket_shutdown(struct socket *sock, int how)
5021 {
5022         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5023 }
5024
5025 static int selinux_socket_unix_stream_connect(struct sock *sock,
5026                                               struct sock *other,
5027                                               struct sock *newsk)
5028 {
5029         struct sk_security_struct *sksec_sock = selinux_sock(sock);
5030         struct sk_security_struct *sksec_other = selinux_sock(other);
5031         struct sk_security_struct *sksec_new = selinux_sock(newsk);
5032         struct common_audit_data ad;
5033         struct lsm_network_audit net;
5034         int err;
5035
5036         ad_net_init_from_sk(&ad, &net, other);
5037
5038         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5039                            sksec_other->sclass,
5040                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5041         if (err)
5042                 return err;
5043
5044         /* server child socket */
5045         sksec_new->peer_sid = sksec_sock->sid;
5046         err = security_sid_mls_copy(sksec_other->sid,
5047                                     sksec_sock->sid, &sksec_new->sid);
5048         if (err)
5049                 return err;
5050
5051         /* connecting socket */
5052         sksec_sock->peer_sid = sksec_new->sid;
5053
5054         return 0;
5055 }
5056
5057 static int selinux_socket_unix_may_send(struct socket *sock,
5058                                         struct socket *other)
5059 {
5060         struct sk_security_struct *ssec = selinux_sock(sock->sk);
5061         struct sk_security_struct *osec = selinux_sock(other->sk);
5062         struct common_audit_data ad;
5063         struct lsm_network_audit net;
5064
5065         ad_net_init_from_sk(&ad, &net, other->sk);
5066
5067         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5068                             &ad);
5069 }
5070
5071 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5072                                     char *addrp, u16 family, u32 peer_sid,
5073                                     struct common_audit_data *ad)
5074 {
5075         int err;
5076         u32 if_sid;
5077         u32 node_sid;
5078
5079         err = sel_netif_sid(ns, ifindex, &if_sid);
5080         if (err)
5081                 return err;
5082         err = avc_has_perm(peer_sid, if_sid,
5083                            SECCLASS_NETIF, NETIF__INGRESS, ad);
5084         if (err)
5085                 return err;
5086
5087         err = sel_netnode_sid(addrp, family, &node_sid);
5088         if (err)
5089                 return err;
5090         return avc_has_perm(peer_sid, node_sid,
5091                             SECCLASS_NODE, NODE__RECVFROM, ad);
5092 }
5093
5094 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5095                                        u16 family)
5096 {
5097         int err = 0;
5098         struct sk_security_struct *sksec = selinux_sock(sk);
5099         u32 sk_sid = sksec->sid;
5100         struct common_audit_data ad;
5101         struct lsm_network_audit net;
5102         char *addrp;
5103
5104         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5105         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5106         if (err)
5107                 return err;
5108
5109         if (selinux_secmark_enabled()) {
5110                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5111                                    PACKET__RECV, &ad);
5112                 if (err)
5113                         return err;
5114         }
5115
5116         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5117         if (err)
5118                 return err;
5119         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5120
5121         return err;
5122 }
5123
5124 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5125 {
5126         int err, peerlbl_active, secmark_active;
5127         struct sk_security_struct *sksec = selinux_sock(sk);
5128         u16 family = sk->sk_family;
5129         u32 sk_sid = sksec->sid;
5130         struct common_audit_data ad;
5131         struct lsm_network_audit net;
5132         char *addrp;
5133
5134         if (family != PF_INET && family != PF_INET6)
5135                 return 0;
5136
5137         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5138         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5139                 family = PF_INET;
5140
5141         /* If any sort of compatibility mode is enabled then handoff processing
5142          * to the selinux_sock_rcv_skb_compat() function to deal with the
5143          * special handling.  We do this in an attempt to keep this function
5144          * as fast and as clean as possible. */
5145         if (!selinux_policycap_netpeer())
5146                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5147
5148         secmark_active = selinux_secmark_enabled();
5149         peerlbl_active = selinux_peerlbl_enabled();
5150         if (!secmark_active && !peerlbl_active)
5151                 return 0;
5152
5153         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5154         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5155         if (err)
5156                 return err;
5157
5158         if (peerlbl_active) {
5159                 u32 peer_sid;
5160
5161                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5162                 if (err)
5163                         return err;
5164                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5165                                                addrp, family, peer_sid, &ad);
5166                 if (err) {
5167                         selinux_netlbl_err(skb, family, err, 0);
5168                         return err;
5169                 }
5170                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5171                                    PEER__RECV, &ad);
5172                 if (err) {
5173                         selinux_netlbl_err(skb, family, err, 0);
5174                         return err;
5175                 }
5176         }
5177
5178         if (secmark_active) {
5179                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5180                                    PACKET__RECV, &ad);
5181                 if (err)
5182                         return err;
5183         }
5184
5185         return err;
5186 }
5187
5188 static int selinux_socket_getpeersec_stream(struct socket *sock,
5189                                             sockptr_t optval, sockptr_t optlen,
5190                                             unsigned int len)
5191 {
5192         int err = 0;
5193         char *scontext = NULL;
5194         u32 scontext_len;
5195         struct sk_security_struct *sksec = selinux_sock(sock->sk);
5196         u32 peer_sid = SECSID_NULL;
5197
5198         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5199             sksec->sclass == SECCLASS_TCP_SOCKET ||
5200             sksec->sclass == SECCLASS_SCTP_SOCKET)
5201                 peer_sid = sksec->peer_sid;
5202         if (peer_sid == SECSID_NULL)
5203                 return -ENOPROTOOPT;
5204
5205         err = security_sid_to_context(peer_sid, &scontext,
5206                                       &scontext_len);
5207         if (err)
5208                 return err;
5209         if (scontext_len > len) {
5210                 err = -ERANGE;
5211                 goto out_len;
5212         }
5213
5214         if (copy_to_sockptr(optval, scontext, scontext_len))
5215                 err = -EFAULT;
5216 out_len:
5217         if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5218                 err = -EFAULT;
5219         kfree(scontext);
5220         return err;
5221 }
5222
5223 static int selinux_socket_getpeersec_dgram(struct socket *sock,
5224                                            struct sk_buff *skb, u32 *secid)
5225 {
5226         u32 peer_secid = SECSID_NULL;
5227         u16 family;
5228
5229         if (skb && skb->protocol == htons(ETH_P_IP))
5230                 family = PF_INET;
5231         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5232                 family = PF_INET6;
5233         else if (sock)
5234                 family = sock->sk->sk_family;
5235         else {
5236                 *secid = SECSID_NULL;
5237                 return -EINVAL;
5238         }
5239
5240         if (sock && family == PF_UNIX) {
5241                 struct inode_security_struct *isec;
5242                 isec = inode_security_novalidate(SOCK_INODE(sock));
5243                 peer_secid = isec->sid;
5244         } else if (skb)
5245                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5246
5247         *secid = peer_secid;
5248         if (peer_secid == SECSID_NULL)
5249                 return -ENOPROTOOPT;
5250         return 0;
5251 }
5252
5253 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5254 {
5255         struct sk_security_struct *sksec = selinux_sock(sk);
5256
5257         sksec->peer_sid = SECINITSID_UNLABELED;
5258         sksec->sid = SECINITSID_UNLABELED;
5259         sksec->sclass = SECCLASS_SOCKET;
5260         selinux_netlbl_sk_security_reset(sksec);
5261
5262         return 0;
5263 }
5264
5265 static void selinux_sk_free_security(struct sock *sk)
5266 {
5267         struct sk_security_struct *sksec = selinux_sock(sk);
5268
5269         selinux_netlbl_sk_security_free(sksec);
5270 }
5271
5272 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5273 {
5274         struct sk_security_struct *sksec = selinux_sock(sk);
5275         struct sk_security_struct *newsksec = selinux_sock(newsk);
5276
5277         newsksec->sid = sksec->sid;
5278         newsksec->peer_sid = sksec->peer_sid;
5279         newsksec->sclass = sksec->sclass;
5280
5281         selinux_netlbl_sk_security_reset(newsksec);
5282 }
5283
5284 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5285 {
5286         if (!sk)
5287                 *secid = SECINITSID_ANY_SOCKET;
5288         else {
5289                 const struct sk_security_struct *sksec = selinux_sock(sk);
5290
5291                 *secid = sksec->sid;
5292         }
5293 }
5294
5295 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5296 {
5297         struct inode_security_struct *isec =
5298                 inode_security_novalidate(SOCK_INODE(parent));
5299         struct sk_security_struct *sksec = selinux_sock(sk);
5300
5301         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5302             sk->sk_family == PF_UNIX)
5303                 isec->sid = sksec->sid;
5304         sksec->sclass = isec->sclass;
5305 }
5306
5307 /*
5308  * Determines peer_secid for the asoc and updates socket's peer label
5309  * if it's the first association on the socket.
5310  */
5311 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5312                                           struct sk_buff *skb)
5313 {
5314         struct sock *sk = asoc->base.sk;
5315         u16 family = sk->sk_family;
5316         struct sk_security_struct *sksec = selinux_sock(sk);
5317         struct common_audit_data ad;
5318         struct lsm_network_audit net;
5319         int err;
5320
5321         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5322         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5323                 family = PF_INET;
5324
5325         if (selinux_peerlbl_enabled()) {
5326                 asoc->peer_secid = SECSID_NULL;
5327
5328                 /* This will return peer_sid = SECSID_NULL if there are
5329                  * no peer labels, see security_net_peersid_resolve().
5330                  */
5331                 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5332                 if (err)
5333                         return err;
5334
5335                 if (asoc->peer_secid == SECSID_NULL)
5336                         asoc->peer_secid = SECINITSID_UNLABELED;
5337         } else {
5338                 asoc->peer_secid = SECINITSID_UNLABELED;
5339         }
5340
5341         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5342                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5343
5344                 /* Here as first association on socket. As the peer SID
5345                  * was allowed by peer recv (and the netif/node checks),
5346                  * then it is approved by policy and used as the primary
5347                  * peer SID for getpeercon(3).
5348                  */
5349                 sksec->peer_sid = asoc->peer_secid;
5350         } else if (sksec->peer_sid != asoc->peer_secid) {
5351                 /* Other association peer SIDs are checked to enforce
5352                  * consistency among the peer SIDs.
5353                  */
5354                 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5355                 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5356                                    sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5357                                    &ad);
5358                 if (err)
5359                         return err;
5360         }
5361         return 0;
5362 }
5363
5364 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5365  * happens on an incoming connect(2), sctp_connectx(3) or
5366  * sctp_sendmsg(3) (with no association already present).
5367  */
5368 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5369                                       struct sk_buff *skb)
5370 {
5371         struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5372         u32 conn_sid;
5373         int err;
5374
5375         if (!selinux_policycap_extsockclass())
5376                 return 0;
5377
5378         err = selinux_sctp_process_new_assoc(asoc, skb);
5379         if (err)
5380                 return err;
5381
5382         /* Compute the MLS component for the connection and store
5383          * the information in asoc. This will be used by SCTP TCP type
5384          * sockets and peeled off connections as they cause a new
5385          * socket to be generated. selinux_sctp_sk_clone() will then
5386          * plug this into the new socket.
5387          */
5388         err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5389         if (err)
5390                 return err;
5391
5392         asoc->secid = conn_sid;
5393
5394         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5395         return selinux_netlbl_sctp_assoc_request(asoc, skb);
5396 }
5397
5398 /* Called when SCTP receives a COOKIE ACK chunk as the final
5399  * response to an association request (initited by us).
5400  */
5401 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5402                                           struct sk_buff *skb)
5403 {
5404         struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5405
5406         if (!selinux_policycap_extsockclass())
5407                 return 0;
5408
5409         /* Inherit secid from the parent socket - this will be picked up
5410          * by selinux_sctp_sk_clone() if the association gets peeled off
5411          * into a new socket.
5412          */
5413         asoc->secid = sksec->sid;
5414
5415         return selinux_sctp_process_new_assoc(asoc, skb);
5416 }
5417
5418 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5419  * based on their @optname.
5420  */
5421 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5422                                      struct sockaddr *address,
5423                                      int addrlen)
5424 {
5425         int len, err = 0, walk_size = 0;
5426         void *addr_buf;
5427         struct sockaddr *addr;
5428         struct socket *sock;
5429
5430         if (!selinux_policycap_extsockclass())
5431                 return 0;
5432
5433         /* Process one or more addresses that may be IPv4 or IPv6 */
5434         sock = sk->sk_socket;
5435         addr_buf = address;
5436
5437         while (walk_size < addrlen) {
5438                 if (walk_size + sizeof(sa_family_t) > addrlen)
5439                         return -EINVAL;
5440
5441                 addr = addr_buf;
5442                 switch (addr->sa_family) {
5443                 case AF_UNSPEC:
5444                 case AF_INET:
5445                         len = sizeof(struct sockaddr_in);
5446                         break;
5447                 case AF_INET6:
5448                         len = sizeof(struct sockaddr_in6);
5449                         break;
5450                 default:
5451                         return -EINVAL;
5452                 }
5453
5454                 if (walk_size + len > addrlen)
5455                         return -EINVAL;
5456
5457                 err = -EINVAL;
5458                 switch (optname) {
5459                 /* Bind checks */
5460                 case SCTP_PRIMARY_ADDR:
5461                 case SCTP_SET_PEER_PRIMARY_ADDR:
5462                 case SCTP_SOCKOPT_BINDX_ADD:
5463                         err = selinux_socket_bind(sock, addr, len);
5464                         break;
5465                 /* Connect checks */
5466                 case SCTP_SOCKOPT_CONNECTX:
5467                 case SCTP_PARAM_SET_PRIMARY:
5468                 case SCTP_PARAM_ADD_IP:
5469                 case SCTP_SENDMSG_CONNECT:
5470                         err = selinux_socket_connect_helper(sock, addr, len);
5471                         if (err)
5472                                 return err;
5473
5474                         /* As selinux_sctp_bind_connect() is called by the
5475                          * SCTP protocol layer, the socket is already locked,
5476                          * therefore selinux_netlbl_socket_connect_locked()
5477                          * is called here. The situations handled are:
5478                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5479                          * whenever a new IP address is added or when a new
5480                          * primary address is selected.
5481                          * Note that an SCTP connect(2) call happens before
5482                          * the SCTP protocol layer and is handled via
5483                          * selinux_socket_connect().
5484                          */
5485                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5486                         break;
5487                 }
5488
5489                 if (err)
5490                         return err;
5491
5492                 addr_buf += len;
5493                 walk_size += len;
5494         }
5495
5496         return 0;
5497 }
5498
5499 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5500 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5501                                   struct sock *newsk)
5502 {
5503         struct sk_security_struct *sksec = selinux_sock(sk);
5504         struct sk_security_struct *newsksec = selinux_sock(newsk);
5505
5506         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5507          * the non-sctp clone version.
5508          */
5509         if (!selinux_policycap_extsockclass())
5510                 return selinux_sk_clone_security(sk, newsk);
5511
5512         newsksec->sid = asoc->secid;
5513         newsksec->peer_sid = asoc->peer_secid;
5514         newsksec->sclass = sksec->sclass;
5515         selinux_netlbl_sctp_sk_clone(sk, newsk);
5516 }
5517
5518 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5519 {
5520         struct sk_security_struct *ssksec = selinux_sock(ssk);
5521         struct sk_security_struct *sksec = selinux_sock(sk);
5522
5523         ssksec->sclass = sksec->sclass;
5524         ssksec->sid = sksec->sid;
5525
5526         /* replace the existing subflow label deleting the existing one
5527          * and re-recreating a new label using the updated context
5528          */
5529         selinux_netlbl_sk_security_free(ssksec);
5530         return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5531 }
5532
5533 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5534                                      struct request_sock *req)
5535 {
5536         struct sk_security_struct *sksec = selinux_sock(sk);
5537         int err;
5538         u16 family = req->rsk_ops->family;
5539         u32 connsid;
5540         u32 peersid;
5541
5542         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5543         if (err)
5544                 return err;
5545         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5546         if (err)
5547                 return err;
5548         req->secid = connsid;
5549         req->peer_secid = peersid;
5550
5551         return selinux_netlbl_inet_conn_request(req, family);
5552 }
5553
5554 static void selinux_inet_csk_clone(struct sock *newsk,
5555                                    const struct request_sock *req)
5556 {
5557         struct sk_security_struct *newsksec = selinux_sock(newsk);
5558
5559         newsksec->sid = req->secid;
5560         newsksec->peer_sid = req->peer_secid;
5561         /* NOTE: Ideally, we should also get the isec->sid for the
5562            new socket in sync, but we don't have the isec available yet.
5563            So we will wait until sock_graft to do it, by which
5564            time it will have been created and available. */
5565
5566         /* We don't need to take any sort of lock here as we are the only
5567          * thread with access to newsksec */
5568         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5569 }
5570
5571 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5572 {
5573         u16 family = sk->sk_family;
5574         struct sk_security_struct *sksec = selinux_sock(sk);
5575
5576         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5577         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5578                 family = PF_INET;
5579
5580         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5581 }
5582
5583 static int selinux_secmark_relabel_packet(u32 sid)
5584 {
5585         return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5586                             NULL);
5587 }
5588
5589 static void selinux_secmark_refcount_inc(void)
5590 {
5591         atomic_inc(&selinux_secmark_refcount);
5592 }
5593
5594 static void selinux_secmark_refcount_dec(void)
5595 {
5596         atomic_dec(&selinux_secmark_refcount);
5597 }
5598
5599 static void selinux_req_classify_flow(const struct request_sock *req,
5600                                       struct flowi_common *flic)
5601 {
5602         flic->flowic_secid = req->secid;
5603 }
5604
5605 static int selinux_tun_dev_alloc_security(void *security)
5606 {
5607         struct tun_security_struct *tunsec = selinux_tun_dev(security);
5608
5609         tunsec->sid = current_sid();
5610         return 0;
5611 }
5612
5613 static int selinux_tun_dev_create(void)
5614 {
5615         u32 sid = current_sid();
5616
5617         /* we aren't taking into account the "sockcreate" SID since the socket
5618          * that is being created here is not a socket in the traditional sense,
5619          * instead it is a private sock, accessible only to the kernel, and
5620          * representing a wide range of network traffic spanning multiple
5621          * connections unlike traditional sockets - check the TUN driver to
5622          * get a better understanding of why this socket is special */
5623
5624         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5625                             NULL);
5626 }
5627
5628 static int selinux_tun_dev_attach_queue(void *security)
5629 {
5630         struct tun_security_struct *tunsec = selinux_tun_dev(security);
5631
5632         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5633                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5634 }
5635
5636 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5637 {
5638         struct tun_security_struct *tunsec = selinux_tun_dev(security);
5639         struct sk_security_struct *sksec = selinux_sock(sk);
5640
5641         /* we don't currently perform any NetLabel based labeling here and it
5642          * isn't clear that we would want to do so anyway; while we could apply
5643          * labeling without the support of the TUN user the resulting labeled
5644          * traffic from the other end of the connection would almost certainly
5645          * cause confusion to the TUN user that had no idea network labeling
5646          * protocols were being used */
5647
5648         sksec->sid = tunsec->sid;
5649         sksec->sclass = SECCLASS_TUN_SOCKET;
5650
5651         return 0;
5652 }
5653
5654 static int selinux_tun_dev_open(void *security)
5655 {
5656         struct tun_security_struct *tunsec = selinux_tun_dev(security);
5657         u32 sid = current_sid();
5658         int err;
5659
5660         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5661                            TUN_SOCKET__RELABELFROM, NULL);
5662         if (err)
5663                 return err;
5664         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5665                            TUN_SOCKET__RELABELTO, NULL);
5666         if (err)
5667                 return err;
5668         tunsec->sid = sid;
5669
5670         return 0;
5671 }
5672
5673 #ifdef CONFIG_NETFILTER
5674
5675 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5676                                        const struct nf_hook_state *state)
5677 {
5678         int ifindex;
5679         u16 family;
5680         char *addrp;
5681         u32 peer_sid;
5682         struct common_audit_data ad;
5683         struct lsm_network_audit net;
5684         int secmark_active, peerlbl_active;
5685
5686         if (!selinux_policycap_netpeer())
5687                 return NF_ACCEPT;
5688
5689         secmark_active = selinux_secmark_enabled();
5690         peerlbl_active = selinux_peerlbl_enabled();
5691         if (!secmark_active && !peerlbl_active)
5692                 return NF_ACCEPT;
5693
5694         family = state->pf;
5695         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5696                 return NF_DROP;
5697
5698         ifindex = state->in->ifindex;
5699         ad_net_init_from_iif(&ad, &net, ifindex, family);
5700         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5701                 return NF_DROP;
5702
5703         if (peerlbl_active) {
5704                 int err;
5705
5706                 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5707                                                addrp, family, peer_sid, &ad);
5708                 if (err) {
5709                         selinux_netlbl_err(skb, family, err, 1);
5710                         return NF_DROP;
5711                 }
5712         }
5713
5714         if (secmark_active)
5715                 if (avc_has_perm(peer_sid, skb->secmark,
5716                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5717                         return NF_DROP;
5718
5719         if (netlbl_enabled())
5720                 /* we do this in the FORWARD path and not the POST_ROUTING
5721                  * path because we want to make sure we apply the necessary
5722                  * labeling before IPsec is applied so we can leverage AH
5723                  * protection */
5724                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5725                         return NF_DROP;
5726
5727         return NF_ACCEPT;
5728 }
5729
5730 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5731                                       const struct nf_hook_state *state)
5732 {
5733         struct sock *sk;
5734         u32 sid;
5735
5736         if (!netlbl_enabled())
5737                 return NF_ACCEPT;
5738
5739         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5740          * because we want to make sure we apply the necessary labeling
5741          * before IPsec is applied so we can leverage AH protection */
5742         sk = sk_to_full_sk(skb->sk);
5743         if (sk) {
5744                 struct sk_security_struct *sksec;
5745
5746                 if (sk_listener(sk))
5747                         /* if the socket is the listening state then this
5748                          * packet is a SYN-ACK packet which means it needs to
5749                          * be labeled based on the connection/request_sock and
5750                          * not the parent socket.  unfortunately, we can't
5751                          * lookup the request_sock yet as it isn't queued on
5752                          * the parent socket until after the SYN-ACK is sent.
5753                          * the "solution" is to simply pass the packet as-is
5754                          * as any IP option based labeling should be copied
5755                          * from the initial connection request (in the IP
5756                          * layer).  it is far from ideal, but until we get a
5757                          * security label in the packet itself this is the
5758                          * best we can do. */
5759                         return NF_ACCEPT;
5760
5761                 /* standard practice, label using the parent socket */
5762                 sksec = selinux_sock(sk);
5763                 sid = sksec->sid;
5764         } else
5765                 sid = SECINITSID_KERNEL;
5766         if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5767                 return NF_DROP;
5768
5769         return NF_ACCEPT;
5770 }
5771
5772
5773 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5774                                         const struct nf_hook_state *state)
5775 {
5776         struct sock *sk;
5777         struct sk_security_struct *sksec;
5778         struct common_audit_data ad;
5779         struct lsm_network_audit net;
5780         u8 proto = 0;
5781
5782         sk = skb_to_full_sk(skb);
5783         if (sk == NULL)
5784                 return NF_ACCEPT;
5785         sksec = selinux_sock(sk);
5786
5787         ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5788         if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5789                 return NF_DROP;
5790
5791         if (selinux_secmark_enabled())
5792                 if (avc_has_perm(sksec->sid, skb->secmark,
5793                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5794                         return NF_DROP_ERR(-ECONNREFUSED);
5795
5796         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5797                 return NF_DROP_ERR(-ECONNREFUSED);
5798
5799         return NF_ACCEPT;
5800 }
5801
5802 static unsigned int selinux_ip_postroute(void *priv,
5803                                          struct sk_buff *skb,
5804                                          const struct nf_hook_state *state)
5805 {
5806         u16 family;
5807         u32 secmark_perm;
5808         u32 peer_sid;
5809         int ifindex;
5810         struct sock *sk;
5811         struct common_audit_data ad;
5812         struct lsm_network_audit net;
5813         char *addrp;
5814         int secmark_active, peerlbl_active;
5815
5816         /* If any sort of compatibility mode is enabled then handoff processing
5817          * to the selinux_ip_postroute_compat() function to deal with the
5818          * special handling.  We do this in an attempt to keep this function
5819          * as fast and as clean as possible. */
5820         if (!selinux_policycap_netpeer())
5821                 return selinux_ip_postroute_compat(skb, state);
5822
5823         secmark_active = selinux_secmark_enabled();
5824         peerlbl_active = selinux_peerlbl_enabled();
5825         if (!secmark_active && !peerlbl_active)
5826                 return NF_ACCEPT;
5827
5828         sk = skb_to_full_sk(skb);
5829
5830 #ifdef CONFIG_XFRM
5831         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5832          * packet transformation so allow the packet to pass without any checks
5833          * since we'll have another chance to perform access control checks
5834          * when the packet is on it's final way out.
5835          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5836          *       is NULL, in this case go ahead and apply access control.
5837          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5838          *       TCP listening state we cannot wait until the XFRM processing
5839          *       is done as we will miss out on the SA label if we do;
5840          *       unfortunately, this means more work, but it is only once per
5841          *       connection. */
5842         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5843             !(sk && sk_listener(sk)))
5844                 return NF_ACCEPT;
5845 #endif
5846
5847         family = state->pf;
5848         if (sk == NULL) {
5849                 /* Without an associated socket the packet is either coming
5850                  * from the kernel or it is being forwarded; check the packet
5851                  * to determine which and if the packet is being forwarded
5852                  * query the packet directly to determine the security label. */
5853                 if (skb->skb_iif) {
5854                         secmark_perm = PACKET__FORWARD_OUT;
5855                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5856                                 return NF_DROP;
5857                 } else {
5858                         secmark_perm = PACKET__SEND;
5859                         peer_sid = SECINITSID_KERNEL;
5860                 }
5861         } else if (sk_listener(sk)) {
5862                 /* Locally generated packet but the associated socket is in the
5863                  * listening state which means this is a SYN-ACK packet.  In
5864                  * this particular case the correct security label is assigned
5865                  * to the connection/request_sock but unfortunately we can't
5866                  * query the request_sock as it isn't queued on the parent
5867                  * socket until after the SYN-ACK packet is sent; the only
5868                  * viable choice is to regenerate the label like we do in
5869                  * selinux_inet_conn_request().  See also selinux_ip_output()
5870                  * for similar problems. */
5871                 u32 skb_sid;
5872                 struct sk_security_struct *sksec;
5873
5874                 sksec = selinux_sock(sk);
5875                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5876                         return NF_DROP;
5877                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5878                  * and the packet has been through at least one XFRM
5879                  * transformation then we must be dealing with the "final"
5880                  * form of labeled IPsec packet; since we've already applied
5881                  * all of our access controls on this packet we can safely
5882                  * pass the packet. */
5883                 if (skb_sid == SECSID_NULL) {
5884                         switch (family) {
5885                         case PF_INET:
5886                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5887                                         return NF_ACCEPT;
5888                                 break;
5889                         case PF_INET6:
5890                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5891                                         return NF_ACCEPT;
5892                                 break;
5893                         default:
5894                                 return NF_DROP_ERR(-ECONNREFUSED);
5895                         }
5896                 }
5897                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5898                         return NF_DROP;
5899                 secmark_perm = PACKET__SEND;
5900         } else {
5901                 /* Locally generated packet, fetch the security label from the
5902                  * associated socket. */
5903                 struct sk_security_struct *sksec = selinux_sock(sk);
5904                 peer_sid = sksec->sid;
5905                 secmark_perm = PACKET__SEND;
5906         }
5907
5908         ifindex = state->out->ifindex;
5909         ad_net_init_from_iif(&ad, &net, ifindex, family);
5910         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5911                 return NF_DROP;
5912
5913         if (secmark_active)
5914                 if (avc_has_perm(peer_sid, skb->secmark,
5915                                  SECCLASS_PACKET, secmark_perm, &ad))
5916                         return NF_DROP_ERR(-ECONNREFUSED);
5917
5918         if (peerlbl_active) {
5919                 u32 if_sid;
5920                 u32 node_sid;
5921
5922                 if (sel_netif_sid(state->net, ifindex, &if_sid))
5923                         return NF_DROP;
5924                 if (avc_has_perm(peer_sid, if_sid,
5925                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5926                         return NF_DROP_ERR(-ECONNREFUSED);
5927
5928                 if (sel_netnode_sid(addrp, family, &node_sid))
5929                         return NF_DROP;
5930                 if (avc_has_perm(peer_sid, node_sid,
5931                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5932                         return NF_DROP_ERR(-ECONNREFUSED);
5933         }
5934
5935         return NF_ACCEPT;
5936 }
5937 #endif  /* CONFIG_NETFILTER */
5938
5939 static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type)
5940 {
5941         struct sk_security_struct *sksec = sk->sk_security;
5942         struct common_audit_data ad;
5943         u8 driver;
5944         u8 xperm;
5945
5946         if (sock_skip_has_perm(sksec->sid))
5947                 return 0;
5948
5949         ad.type = LSM_AUDIT_DATA_NLMSGTYPE;
5950         ad.u.nlmsg_type = nlmsg_type;
5951
5952         driver = nlmsg_type >> 8;
5953         xperm = nlmsg_type & 0xff;
5954
5955         return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass,
5956                                       perms, driver, AVC_EXT_NLMSG, xperm, &ad);
5957 }
5958
5959 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5960 {
5961         int rc = 0;
5962         unsigned int msg_len;
5963         unsigned int data_len = skb->len;
5964         unsigned char *data = skb->data;
5965         struct nlmsghdr *nlh;
5966         struct sk_security_struct *sksec = selinux_sock(sk);
5967         u16 sclass = sksec->sclass;
5968         u32 perm;
5969
5970         while (data_len >= nlmsg_total_size(0)) {
5971                 nlh = (struct nlmsghdr *)data;
5972
5973                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5974                  *       users which means we can't reject skb's with bogus
5975                  *       length fields; our solution is to follow what
5976                  *       netlink_rcv_skb() does and simply skip processing at
5977                  *       messages with length fields that are clearly junk
5978                  */
5979                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5980                         return 0;
5981
5982                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5983                 if (rc == 0) {
5984                         if (selinux_policycap_netlink_xperm()) {
5985                                 rc = nlmsg_sock_has_extended_perms(
5986                                         sk, perm, nlh->nlmsg_type);
5987                         } else {
5988                                 rc = sock_has_perm(sk, perm);
5989                         }
5990                         if (rc)
5991                                 return rc;
5992                 } else if (rc == -EINVAL) {
5993                         /* -EINVAL is a missing msg/perm mapping */
5994                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5995                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5996                                 " pid=%d comm=%s\n",
5997                                 sk->sk_protocol, nlh->nlmsg_type,
5998                                 secclass_map[sclass - 1].name,
5999                                 task_pid_nr(current), current->comm);
6000                         if (enforcing_enabled() &&
6001                             !security_get_allow_unknown())
6002                                 return rc;
6003                         rc = 0;
6004                 } else if (rc == -ENOENT) {
6005                         /* -ENOENT is a missing socket/class mapping, ignore */
6006                         rc = 0;
6007                 } else {
6008                         return rc;
6009                 }
6010
6011                 /* move to the next message after applying netlink padding */
6012                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6013                 if (msg_len >= data_len)
6014                         return 0;
6015                 data_len -= msg_len;
6016                 data += msg_len;
6017         }
6018
6019         return rc;
6020 }
6021
6022 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6023 {
6024         isec->sclass = sclass;
6025         isec->sid = current_sid();
6026 }
6027
6028 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6029                         u32 perms)
6030 {
6031         struct ipc_security_struct *isec;
6032         struct common_audit_data ad;
6033         u32 sid = current_sid();
6034
6035         isec = selinux_ipc(ipc_perms);
6036
6037         ad.type = LSM_AUDIT_DATA_IPC;
6038         ad.u.ipc_id = ipc_perms->key;
6039
6040         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6041 }
6042
6043 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6044 {
6045         struct msg_security_struct *msec;
6046
6047         msec = selinux_msg_msg(msg);
6048         msec->sid = SECINITSID_UNLABELED;
6049
6050         return 0;
6051 }
6052
6053 /* message queue security operations */
6054 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6055 {
6056         struct ipc_security_struct *isec;
6057         struct common_audit_data ad;
6058         u32 sid = current_sid();
6059
6060         isec = selinux_ipc(msq);
6061         ipc_init_security(isec, SECCLASS_MSGQ);
6062
6063         ad.type = LSM_AUDIT_DATA_IPC;
6064         ad.u.ipc_id = msq->key;
6065
6066         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6067                             MSGQ__CREATE, &ad);
6068 }
6069
6070 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6071 {
6072         struct ipc_security_struct *isec;
6073         struct common_audit_data ad;
6074         u32 sid = current_sid();
6075
6076         isec = selinux_ipc(msq);
6077
6078         ad.type = LSM_AUDIT_DATA_IPC;
6079         ad.u.ipc_id = msq->key;
6080
6081         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6082                             MSGQ__ASSOCIATE, &ad);
6083 }
6084
6085 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6086 {
6087         u32 perms;
6088
6089         switch (cmd) {
6090         case IPC_INFO:
6091         case MSG_INFO:
6092                 /* No specific object, just general system-wide information. */
6093                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6094                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6095         case IPC_STAT:
6096         case MSG_STAT:
6097         case MSG_STAT_ANY:
6098                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6099                 break;
6100         case IPC_SET:
6101                 perms = MSGQ__SETATTR;
6102                 break;
6103         case IPC_RMID:
6104                 perms = MSGQ__DESTROY;
6105                 break;
6106         default:
6107                 return 0;
6108         }
6109
6110         return ipc_has_perm(msq, perms);
6111 }
6112
6113 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6114 {
6115         struct ipc_security_struct *isec;
6116         struct msg_security_struct *msec;
6117         struct common_audit_data ad;
6118         u32 sid = current_sid();
6119         int rc;
6120
6121         isec = selinux_ipc(msq);
6122         msec = selinux_msg_msg(msg);
6123
6124         /*
6125          * First time through, need to assign label to the message
6126          */
6127         if (msec->sid == SECINITSID_UNLABELED) {
6128                 /*
6129                  * Compute new sid based on current process and
6130                  * message queue this message will be stored in
6131                  */
6132                 rc = security_transition_sid(sid, isec->sid,
6133                                              SECCLASS_MSG, NULL, &msec->sid);
6134                 if (rc)
6135                         return rc;
6136         }
6137
6138         ad.type = LSM_AUDIT_DATA_IPC;
6139         ad.u.ipc_id = msq->key;
6140
6141         /* Can this process write to the queue? */
6142         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6143                           MSGQ__WRITE, &ad);
6144         if (!rc)
6145                 /* Can this process send the message */
6146                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6147                                   MSG__SEND, &ad);
6148         if (!rc)
6149                 /* Can the message be put in the queue? */
6150                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6151                                   MSGQ__ENQUEUE, &ad);
6152
6153         return rc;
6154 }
6155
6156 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6157                                     struct task_struct *target,
6158                                     long type, int mode)
6159 {
6160         struct ipc_security_struct *isec;
6161         struct msg_security_struct *msec;
6162         struct common_audit_data ad;
6163         u32 sid = task_sid_obj(target);
6164         int rc;
6165
6166         isec = selinux_ipc(msq);
6167         msec = selinux_msg_msg(msg);
6168
6169         ad.type = LSM_AUDIT_DATA_IPC;
6170         ad.u.ipc_id = msq->key;
6171
6172         rc = avc_has_perm(sid, isec->sid,
6173                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6174         if (!rc)
6175                 rc = avc_has_perm(sid, msec->sid,
6176                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6177         return rc;
6178 }
6179
6180 /* Shared Memory security operations */
6181 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6182 {
6183         struct ipc_security_struct *isec;
6184         struct common_audit_data ad;
6185         u32 sid = current_sid();
6186
6187         isec = selinux_ipc(shp);
6188         ipc_init_security(isec, SECCLASS_SHM);
6189
6190         ad.type = LSM_AUDIT_DATA_IPC;
6191         ad.u.ipc_id = shp->key;
6192
6193         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6194                             SHM__CREATE, &ad);
6195 }
6196
6197 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6198 {
6199         struct ipc_security_struct *isec;
6200         struct common_audit_data ad;
6201         u32 sid = current_sid();
6202
6203         isec = selinux_ipc(shp);
6204
6205         ad.type = LSM_AUDIT_DATA_IPC;
6206         ad.u.ipc_id = shp->key;
6207
6208         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6209                             SHM__ASSOCIATE, &ad);
6210 }
6211
6212 /* Note, at this point, shp is locked down */
6213 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6214 {
6215         u32 perms;
6216
6217         switch (cmd) {
6218         case IPC_INFO:
6219         case SHM_INFO:
6220                 /* No specific object, just general system-wide information. */
6221                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6222                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6223         case IPC_STAT:
6224         case SHM_STAT:
6225         case SHM_STAT_ANY:
6226                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6227                 break;
6228         case IPC_SET:
6229                 perms = SHM__SETATTR;
6230                 break;
6231         case SHM_LOCK:
6232         case SHM_UNLOCK:
6233                 perms = SHM__LOCK;
6234                 break;
6235         case IPC_RMID:
6236                 perms = SHM__DESTROY;
6237                 break;
6238         default:
6239                 return 0;
6240         }
6241
6242         return ipc_has_perm(shp, perms);
6243 }
6244
6245 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6246                              char __user *shmaddr, int shmflg)
6247 {
6248         u32 perms;
6249
6250         if (shmflg & SHM_RDONLY)
6251                 perms = SHM__READ;
6252         else
6253                 perms = SHM__READ | SHM__WRITE;
6254
6255         return ipc_has_perm(shp, perms);
6256 }
6257
6258 /* Semaphore security operations */
6259 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6260 {
6261         struct ipc_security_struct *isec;
6262         struct common_audit_data ad;
6263         u32 sid = current_sid();
6264
6265         isec = selinux_ipc(sma);
6266         ipc_init_security(isec, SECCLASS_SEM);
6267
6268         ad.type = LSM_AUDIT_DATA_IPC;
6269         ad.u.ipc_id = sma->key;
6270
6271         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6272                             SEM__CREATE, &ad);
6273 }
6274
6275 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6276 {
6277         struct ipc_security_struct *isec;
6278         struct common_audit_data ad;
6279         u32 sid = current_sid();
6280
6281         isec = selinux_ipc(sma);
6282
6283         ad.type = LSM_AUDIT_DATA_IPC;
6284         ad.u.ipc_id = sma->key;
6285
6286         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6287                             SEM__ASSOCIATE, &ad);
6288 }
6289
6290 /* Note, at this point, sma is locked down */
6291 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6292 {
6293         int err;
6294         u32 perms;
6295
6296         switch (cmd) {
6297         case IPC_INFO:
6298         case SEM_INFO:
6299                 /* No specific object, just general system-wide information. */
6300                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6301                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6302         case GETPID:
6303         case GETNCNT:
6304         case GETZCNT:
6305                 perms = SEM__GETATTR;
6306                 break;
6307         case GETVAL:
6308         case GETALL:
6309                 perms = SEM__READ;
6310                 break;
6311         case SETVAL:
6312         case SETALL:
6313                 perms = SEM__WRITE;
6314                 break;
6315         case IPC_RMID:
6316                 perms = SEM__DESTROY;
6317                 break;
6318         case IPC_SET:
6319                 perms = SEM__SETATTR;
6320                 break;
6321         case IPC_STAT:
6322         case SEM_STAT:
6323         case SEM_STAT_ANY:
6324                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6325                 break;
6326         default:
6327                 return 0;
6328         }
6329
6330         err = ipc_has_perm(sma, perms);
6331         return err;
6332 }
6333
6334 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6335                              struct sembuf *sops, unsigned nsops, int alter)
6336 {
6337         u32 perms;
6338
6339         if (alter)
6340                 perms = SEM__READ | SEM__WRITE;
6341         else
6342                 perms = SEM__READ;
6343
6344         return ipc_has_perm(sma, perms);
6345 }
6346
6347 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6348 {
6349         u32 av = 0;
6350
6351         av = 0;
6352         if (flag & S_IRUGO)
6353                 av |= IPC__UNIX_READ;
6354         if (flag & S_IWUGO)
6355                 av |= IPC__UNIX_WRITE;
6356
6357         if (av == 0)
6358                 return 0;
6359
6360         return ipc_has_perm(ipcp, av);
6361 }
6362
6363 static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp,
6364                                    struct lsm_prop *prop)
6365 {
6366         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6367         prop->selinux.secid = isec->sid;
6368 }
6369
6370 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6371 {
6372         if (inode)
6373                 inode_doinit_with_dentry(inode, dentry);
6374 }
6375
6376 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6377                                char **value)
6378 {
6379         const struct task_security_struct *tsec;
6380         int error;
6381         u32 sid;
6382         u32 len;
6383
6384         rcu_read_lock();
6385         tsec = selinux_cred(__task_cred(p));
6386         if (p != current) {
6387                 error = avc_has_perm(current_sid(), tsec->sid,
6388                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6389                 if (error)
6390                         goto err_unlock;
6391         }
6392         switch (attr) {
6393         case LSM_ATTR_CURRENT:
6394                 sid = tsec->sid;
6395                 break;
6396         case LSM_ATTR_PREV:
6397                 sid = tsec->osid;
6398                 break;
6399         case LSM_ATTR_EXEC:
6400                 sid = tsec->exec_sid;
6401                 break;
6402         case LSM_ATTR_FSCREATE:
6403                 sid = tsec->create_sid;
6404                 break;
6405         case LSM_ATTR_KEYCREATE:
6406                 sid = tsec->keycreate_sid;
6407                 break;
6408         case LSM_ATTR_SOCKCREATE:
6409                 sid = tsec->sockcreate_sid;
6410                 break;
6411         default:
6412                 error = -EOPNOTSUPP;
6413                 goto err_unlock;
6414         }
6415         rcu_read_unlock();
6416
6417         if (sid == SECSID_NULL) {
6418                 *value = NULL;
6419                 return 0;
6420         }
6421
6422         error = security_sid_to_context(sid, value, &len);
6423         if (error)
6424                 return error;
6425         return len;
6426
6427 err_unlock:
6428         rcu_read_unlock();
6429         return error;
6430 }
6431
6432 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6433 {
6434         struct task_security_struct *tsec;
6435         struct cred *new;
6436         u32 mysid = current_sid(), sid = 0, ptsid;
6437         int error;
6438         char *str = value;
6439
6440         /*
6441          * Basic control over ability to set these attributes at all.
6442          */
6443         switch (attr) {
6444         case LSM_ATTR_EXEC:
6445                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6446                                      PROCESS__SETEXEC, NULL);
6447                 break;
6448         case LSM_ATTR_FSCREATE:
6449                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6450                                      PROCESS__SETFSCREATE, NULL);
6451                 break;
6452         case LSM_ATTR_KEYCREATE:
6453                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6454                                      PROCESS__SETKEYCREATE, NULL);
6455                 break;
6456         case LSM_ATTR_SOCKCREATE:
6457                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6458                                      PROCESS__SETSOCKCREATE, NULL);
6459                 break;
6460         case LSM_ATTR_CURRENT:
6461                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6462                                      PROCESS__SETCURRENT, NULL);
6463                 break;
6464         default:
6465                 error = -EOPNOTSUPP;
6466                 break;
6467         }
6468         if (error)
6469                 return error;
6470
6471         /* Obtain a SID for the context, if one was specified. */
6472         if (size && str[0] && str[0] != '\n') {
6473                 if (str[size-1] == '\n') {
6474                         str[size-1] = 0;
6475                         size--;
6476                 }
6477                 error = security_context_to_sid(value, size,
6478                                                 &sid, GFP_KERNEL);
6479                 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6480                         if (!has_cap_mac_admin(true)) {
6481                                 struct audit_buffer *ab;
6482                                 size_t audit_size;
6483
6484                                 /* We strip a nul only if it is at the end,
6485                                  * otherwise the context contains a nul and
6486                                  * we should audit that */
6487                                 if (str[size - 1] == '\0')
6488                                         audit_size = size - 1;
6489                                 else
6490                                         audit_size = size;
6491                                 ab = audit_log_start(audit_context(),
6492                                                      GFP_ATOMIC,
6493                                                      AUDIT_SELINUX_ERR);
6494                                 if (!ab)
6495                                         return error;
6496                                 audit_log_format(ab, "op=fscreate invalid_context=");
6497                                 audit_log_n_untrustedstring(ab, value,
6498                                                             audit_size);
6499                                 audit_log_end(ab);
6500
6501                                 return error;
6502                         }
6503                         error = security_context_to_sid_force(value, size,
6504                                                         &sid);
6505                 }
6506                 if (error)
6507                         return error;
6508         }
6509
6510         new = prepare_creds();
6511         if (!new)
6512                 return -ENOMEM;
6513
6514         /* Permission checking based on the specified context is
6515            performed during the actual operation (execve,
6516            open/mkdir/...), when we know the full context of the
6517            operation.  See selinux_bprm_creds_for_exec for the execve
6518            checks and may_create for the file creation checks. The
6519            operation will then fail if the context is not permitted. */
6520         tsec = selinux_cred(new);
6521         if (attr == LSM_ATTR_EXEC) {
6522                 tsec->exec_sid = sid;
6523         } else if (attr == LSM_ATTR_FSCREATE) {
6524                 tsec->create_sid = sid;
6525         } else if (attr == LSM_ATTR_KEYCREATE) {
6526                 if (sid) {
6527                         error = avc_has_perm(mysid, sid,
6528                                              SECCLASS_KEY, KEY__CREATE, NULL);
6529                         if (error)
6530                                 goto abort_change;
6531                 }
6532                 tsec->keycreate_sid = sid;
6533         } else if (attr == LSM_ATTR_SOCKCREATE) {
6534                 tsec->sockcreate_sid = sid;
6535         } else if (attr == LSM_ATTR_CURRENT) {
6536                 error = -EINVAL;
6537                 if (sid == 0)
6538                         goto abort_change;
6539
6540                 if (!current_is_single_threaded()) {
6541                         error = security_bounded_transition(tsec->sid, sid);
6542                         if (error)
6543                                 goto abort_change;
6544                 }
6545
6546                 /* Check permissions for the transition. */
6547                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6548                                      PROCESS__DYNTRANSITION, NULL);
6549                 if (error)
6550                         goto abort_change;
6551
6552                 /* Check for ptracing, and update the task SID if ok.
6553                    Otherwise, leave SID unchanged and fail. */
6554                 ptsid = ptrace_parent_sid();
6555                 if (ptsid != 0) {
6556                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6557                                              PROCESS__PTRACE, NULL);
6558                         if (error)
6559                                 goto abort_change;
6560                 }
6561
6562                 tsec->sid = sid;
6563         } else {
6564                 error = -EINVAL;
6565                 goto abort_change;
6566         }
6567
6568         commit_creds(new);
6569         return size;
6570
6571 abort_change:
6572         abort_creds(new);
6573         return error;
6574 }
6575
6576 /**
6577  * selinux_getselfattr - Get SELinux current task attributes
6578  * @attr: the requested attribute
6579  * @ctx: buffer to receive the result
6580  * @size: buffer size (input), buffer size used (output)
6581  * @flags: unused
6582  *
6583  * Fill the passed user space @ctx with the details of the requested
6584  * attribute.
6585  *
6586  * Returns the number of attributes on success, an error code otherwise.
6587  * There will only ever be one attribute.
6588  */
6589 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6590                                u32 *size, u32 flags)
6591 {
6592         int rc;
6593         char *val = NULL;
6594         int val_len;
6595
6596         val_len = selinux_lsm_getattr(attr, current, &val);
6597         if (val_len < 0)
6598                 return val_len;
6599         rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6600         kfree(val);
6601         return (!rc ? 1 : rc);
6602 }
6603
6604 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6605                                u32 size, u32 flags)
6606 {
6607         int rc;
6608
6609         rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6610         if (rc > 0)
6611                 return 0;
6612         return rc;
6613 }
6614
6615 static int selinux_getprocattr(struct task_struct *p,
6616                                const char *name, char **value)
6617 {
6618         unsigned int attr = lsm_name_to_attr(name);
6619         int rc;
6620
6621         if (attr) {
6622                 rc = selinux_lsm_getattr(attr, p, value);
6623                 if (rc != -EOPNOTSUPP)
6624                         return rc;
6625         }
6626
6627         return -EINVAL;
6628 }
6629
6630 static int selinux_setprocattr(const char *name, void *value, size_t size)
6631 {
6632         int attr = lsm_name_to_attr(name);
6633
6634         if (attr)
6635                 return selinux_lsm_setattr(attr, value, size);
6636         return -EINVAL;
6637 }
6638
6639 static int selinux_ismaclabel(const char *name)
6640 {
6641         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6642 }
6643
6644 static int selinux_secid_to_secctx(u32 secid, struct lsm_context *cp)
6645 {
6646         u32 seclen;
6647         int ret;
6648
6649         if (cp) {
6650                 cp->id = LSM_ID_SELINUX;
6651                 ret = security_sid_to_context(secid, &cp->context, &cp->len);
6652                 if (ret < 0)
6653                         return ret;
6654                 return cp->len;
6655         }
6656         ret = security_sid_to_context(secid, NULL, &seclen);
6657         if (ret < 0)
6658                 return ret;
6659         return seclen;
6660 }
6661
6662 static int selinux_lsmprop_to_secctx(struct lsm_prop *prop,
6663                                      struct lsm_context *cp)
6664 {
6665         return selinux_secid_to_secctx(prop->selinux.secid, cp);
6666 }
6667
6668 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6669 {
6670         return security_context_to_sid(secdata, seclen,
6671                                        secid, GFP_KERNEL);
6672 }
6673
6674 static void selinux_release_secctx(struct lsm_context *cp)
6675 {
6676         if (cp->id == LSM_ID_SELINUX) {
6677                 kfree(cp->context);
6678                 cp->context = NULL;
6679                 cp->id = LSM_ID_UNDEF;
6680         }
6681 }
6682
6683 static void selinux_inode_invalidate_secctx(struct inode *inode)
6684 {
6685         struct inode_security_struct *isec = selinux_inode(inode);
6686
6687         spin_lock(&isec->lock);
6688         isec->initialized = LABEL_INVALID;
6689         spin_unlock(&isec->lock);
6690 }
6691
6692 /*
6693  *      called with inode->i_mutex locked
6694  */
6695 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6696 {
6697         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6698                                            ctx, ctxlen, 0);
6699         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6700         return rc == -EOPNOTSUPP ? 0 : rc;
6701 }
6702
6703 /*
6704  *      called with inode->i_mutex locked
6705  */
6706 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6707 {
6708         return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6709                                      ctx, ctxlen, 0, NULL);
6710 }
6711
6712 static int selinux_inode_getsecctx(struct inode *inode, struct lsm_context *cp)
6713 {
6714         int len;
6715         len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6716                                         XATTR_SELINUX_SUFFIX,
6717                                         (void **)&cp->context, true);
6718         if (len < 0)
6719                 return len;
6720         cp->len = len;
6721         cp->id = LSM_ID_SELINUX;
6722         return 0;
6723 }
6724 #ifdef CONFIG_KEYS
6725
6726 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6727                              unsigned long flags)
6728 {
6729         const struct task_security_struct *tsec;
6730         struct key_security_struct *ksec = selinux_key(k);
6731
6732         tsec = selinux_cred(cred);
6733         if (tsec->keycreate_sid)
6734                 ksec->sid = tsec->keycreate_sid;
6735         else
6736                 ksec->sid = tsec->sid;
6737
6738         return 0;
6739 }
6740
6741 static int selinux_key_permission(key_ref_t key_ref,
6742                                   const struct cred *cred,
6743                                   enum key_need_perm need_perm)
6744 {
6745         struct key *key;
6746         struct key_security_struct *ksec;
6747         u32 perm, sid;
6748
6749         switch (need_perm) {
6750         case KEY_NEED_VIEW:
6751                 perm = KEY__VIEW;
6752                 break;
6753         case KEY_NEED_READ:
6754                 perm = KEY__READ;
6755                 break;
6756         case KEY_NEED_WRITE:
6757                 perm = KEY__WRITE;
6758                 break;
6759         case KEY_NEED_SEARCH:
6760                 perm = KEY__SEARCH;
6761                 break;
6762         case KEY_NEED_LINK:
6763                 perm = KEY__LINK;
6764                 break;
6765         case KEY_NEED_SETATTR:
6766                 perm = KEY__SETATTR;
6767                 break;
6768         case KEY_NEED_UNLINK:
6769         case KEY_SYSADMIN_OVERRIDE:
6770         case KEY_AUTHTOKEN_OVERRIDE:
6771         case KEY_DEFER_PERM_CHECK:
6772                 return 0;
6773         default:
6774                 WARN_ON(1);
6775                 return -EPERM;
6776
6777         }
6778
6779         sid = cred_sid(cred);
6780         key = key_ref_to_ptr(key_ref);
6781         ksec = selinux_key(key);
6782
6783         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6784 }
6785
6786 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6787 {
6788         struct key_security_struct *ksec = selinux_key(key);
6789         char *context = NULL;
6790         unsigned len;
6791         int rc;
6792
6793         rc = security_sid_to_context(ksec->sid,
6794                                      &context, &len);
6795         if (!rc)
6796                 rc = len;
6797         *_buffer = context;
6798         return rc;
6799 }
6800
6801 #ifdef CONFIG_KEY_NOTIFICATIONS
6802 static int selinux_watch_key(struct key *key)
6803 {
6804         struct key_security_struct *ksec = selinux_key(key);
6805         u32 sid = current_sid();
6806
6807         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6808 }
6809 #endif
6810 #endif
6811
6812 #ifdef CONFIG_SECURITY_INFINIBAND
6813 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6814 {
6815         struct common_audit_data ad;
6816         int err;
6817         u32 sid = 0;
6818         struct ib_security_struct *sec = ib_sec;
6819         struct lsm_ibpkey_audit ibpkey;
6820
6821         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6822         if (err)
6823                 return err;
6824
6825         ad.type = LSM_AUDIT_DATA_IBPKEY;
6826         ibpkey.subnet_prefix = subnet_prefix;
6827         ibpkey.pkey = pkey_val;
6828         ad.u.ibpkey = &ibpkey;
6829         return avc_has_perm(sec->sid, sid,
6830                             SECCLASS_INFINIBAND_PKEY,
6831                             INFINIBAND_PKEY__ACCESS, &ad);
6832 }
6833
6834 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6835                                             u8 port_num)
6836 {
6837         struct common_audit_data ad;
6838         int err;
6839         u32 sid = 0;
6840         struct ib_security_struct *sec = ib_sec;
6841         struct lsm_ibendport_audit ibendport;
6842
6843         err = security_ib_endport_sid(dev_name, port_num,
6844                                       &sid);
6845
6846         if (err)
6847                 return err;
6848
6849         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6850         ibendport.dev_name = dev_name;
6851         ibendport.port = port_num;
6852         ad.u.ibendport = &ibendport;
6853         return avc_has_perm(sec->sid, sid,
6854                             SECCLASS_INFINIBAND_ENDPORT,
6855                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6856 }
6857
6858 static int selinux_ib_alloc_security(void *ib_sec)
6859 {
6860         struct ib_security_struct *sec = selinux_ib(ib_sec);
6861
6862         sec->sid = current_sid();
6863         return 0;
6864 }
6865 #endif
6866
6867 #ifdef CONFIG_BPF_SYSCALL
6868 static int selinux_bpf(int cmd, union bpf_attr *attr,
6869                                      unsigned int size)
6870 {
6871         u32 sid = current_sid();
6872         int ret;
6873
6874         switch (cmd) {
6875         case BPF_MAP_CREATE:
6876                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6877                                    NULL);
6878                 break;
6879         case BPF_PROG_LOAD:
6880                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6881                                    NULL);
6882                 break;
6883         default:
6884                 ret = 0;
6885                 break;
6886         }
6887
6888         return ret;
6889 }
6890
6891 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6892 {
6893         u32 av = 0;
6894
6895         if (fmode & FMODE_READ)
6896                 av |= BPF__MAP_READ;
6897         if (fmode & FMODE_WRITE)
6898                 av |= BPF__MAP_WRITE;
6899         return av;
6900 }
6901
6902 /* This function will check the file pass through unix socket or binder to see
6903  * if it is a bpf related object. And apply corresponding checks on the bpf
6904  * object based on the type. The bpf maps and programs, not like other files and
6905  * socket, are using a shared anonymous inode inside the kernel as their inode.
6906  * So checking that inode cannot identify if the process have privilege to
6907  * access the bpf object and that's why we have to add this additional check in
6908  * selinux_file_receive and selinux_binder_transfer_files.
6909  */
6910 static int bpf_fd_pass(const struct file *file, u32 sid)
6911 {
6912         struct bpf_security_struct *bpfsec;
6913         struct bpf_prog *prog;
6914         struct bpf_map *map;
6915         int ret;
6916
6917         if (file->f_op == &bpf_map_fops) {
6918                 map = file->private_data;
6919                 bpfsec = map->security;
6920                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6921                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6922                 if (ret)
6923                         return ret;
6924         } else if (file->f_op == &bpf_prog_fops) {
6925                 prog = file->private_data;
6926                 bpfsec = prog->aux->security;
6927                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6928                                    BPF__PROG_RUN, NULL);
6929                 if (ret)
6930                         return ret;
6931         }
6932         return 0;
6933 }
6934
6935 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6936 {
6937         u32 sid = current_sid();
6938         struct bpf_security_struct *bpfsec;
6939
6940         bpfsec = map->security;
6941         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6942                             bpf_map_fmode_to_av(fmode), NULL);
6943 }
6944
6945 static int selinux_bpf_prog(struct bpf_prog *prog)
6946 {
6947         u32 sid = current_sid();
6948         struct bpf_security_struct *bpfsec;
6949
6950         bpfsec = prog->aux->security;
6951         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6952                             BPF__PROG_RUN, NULL);
6953 }
6954
6955 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6956                                   struct bpf_token *token)
6957 {
6958         struct bpf_security_struct *bpfsec;
6959
6960         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6961         if (!bpfsec)
6962                 return -ENOMEM;
6963
6964         bpfsec->sid = current_sid();
6965         map->security = bpfsec;
6966
6967         return 0;
6968 }
6969
6970 static void selinux_bpf_map_free(struct bpf_map *map)
6971 {
6972         struct bpf_security_struct *bpfsec = map->security;
6973
6974         map->security = NULL;
6975         kfree(bpfsec);
6976 }
6977
6978 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6979                                  struct bpf_token *token)
6980 {
6981         struct bpf_security_struct *bpfsec;
6982
6983         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6984         if (!bpfsec)
6985                 return -ENOMEM;
6986
6987         bpfsec->sid = current_sid();
6988         prog->aux->security = bpfsec;
6989
6990         return 0;
6991 }
6992
6993 static void selinux_bpf_prog_free(struct bpf_prog *prog)
6994 {
6995         struct bpf_security_struct *bpfsec = prog->aux->security;
6996
6997         prog->aux->security = NULL;
6998         kfree(bpfsec);
6999 }
7000
7001 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
7002                                     const struct path *path)
7003 {
7004         struct bpf_security_struct *bpfsec;
7005
7006         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
7007         if (!bpfsec)
7008                 return -ENOMEM;
7009
7010         bpfsec->sid = current_sid();
7011         token->security = bpfsec;
7012
7013         return 0;
7014 }
7015
7016 static void selinux_bpf_token_free(struct bpf_token *token)
7017 {
7018         struct bpf_security_struct *bpfsec = token->security;
7019
7020         token->security = NULL;
7021         kfree(bpfsec);
7022 }
7023 #endif
7024
7025 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
7026         .lbs_cred = sizeof(struct task_security_struct),
7027         .lbs_file = sizeof(struct file_security_struct),
7028         .lbs_inode = sizeof(struct inode_security_struct),
7029         .lbs_ipc = sizeof(struct ipc_security_struct),
7030         .lbs_key = sizeof(struct key_security_struct),
7031         .lbs_msg_msg = sizeof(struct msg_security_struct),
7032 #ifdef CONFIG_PERF_EVENTS
7033         .lbs_perf_event = sizeof(struct perf_event_security_struct),
7034 #endif
7035         .lbs_sock = sizeof(struct sk_security_struct),
7036         .lbs_superblock = sizeof(struct superblock_security_struct),
7037         .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7038         .lbs_tun_dev = sizeof(struct tun_security_struct),
7039         .lbs_ib = sizeof(struct ib_security_struct),
7040 };
7041
7042 #ifdef CONFIG_PERF_EVENTS
7043 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7044 {
7045         u32 requested, sid = current_sid();
7046
7047         if (type == PERF_SECURITY_OPEN)
7048                 requested = PERF_EVENT__OPEN;
7049         else if (type == PERF_SECURITY_CPU)
7050                 requested = PERF_EVENT__CPU;
7051         else if (type == PERF_SECURITY_KERNEL)
7052                 requested = PERF_EVENT__KERNEL;
7053         else if (type == PERF_SECURITY_TRACEPOINT)
7054                 requested = PERF_EVENT__TRACEPOINT;
7055         else
7056                 return -EINVAL;
7057
7058         return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7059                             requested, NULL);
7060 }
7061
7062 static int selinux_perf_event_alloc(struct perf_event *event)
7063 {
7064         struct perf_event_security_struct *perfsec;
7065
7066         perfsec = selinux_perf_event(event->security);
7067         perfsec->sid = current_sid();
7068
7069         return 0;
7070 }
7071
7072 static int selinux_perf_event_read(struct perf_event *event)
7073 {
7074         struct perf_event_security_struct *perfsec = event->security;
7075         u32 sid = current_sid();
7076
7077         return avc_has_perm(sid, perfsec->sid,
7078                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7079 }
7080
7081 static int selinux_perf_event_write(struct perf_event *event)
7082 {
7083         struct perf_event_security_struct *perfsec = event->security;
7084         u32 sid = current_sid();
7085
7086         return avc_has_perm(sid, perfsec->sid,
7087                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7088 }
7089 #endif
7090
7091 #ifdef CONFIG_IO_URING
7092 /**
7093  * selinux_uring_override_creds - check the requested cred override
7094  * @new: the target creds
7095  *
7096  * Check to see if the current task is allowed to override it's credentials
7097  * to service an io_uring operation.
7098  */
7099 static int selinux_uring_override_creds(const struct cred *new)
7100 {
7101         return avc_has_perm(current_sid(), cred_sid(new),
7102                             SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7103 }
7104
7105 /**
7106  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7107  *
7108  * Check to see if the current task is allowed to create a new io_uring
7109  * kernel polling thread.
7110  */
7111 static int selinux_uring_sqpoll(void)
7112 {
7113         u32 sid = current_sid();
7114
7115         return avc_has_perm(sid, sid,
7116                             SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7117 }
7118
7119 /**
7120  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7121  * @ioucmd: the io_uring command structure
7122  *
7123  * Check to see if the current domain is allowed to execute an
7124  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7125  *
7126  */
7127 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7128 {
7129         struct file *file = ioucmd->file;
7130         struct inode *inode = file_inode(file);
7131         struct inode_security_struct *isec = selinux_inode(inode);
7132         struct common_audit_data ad;
7133
7134         ad.type = LSM_AUDIT_DATA_FILE;
7135         ad.u.file = file;
7136
7137         return avc_has_perm(current_sid(), isec->sid,
7138                             SECCLASS_IO_URING, IO_URING__CMD, &ad);
7139 }
7140 #endif /* CONFIG_IO_URING */
7141
7142 static const struct lsm_id selinux_lsmid = {
7143         .name = "selinux",
7144         .id = LSM_ID_SELINUX,
7145 };
7146
7147 /*
7148  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7149  * 1. any hooks that don't belong to (2.) or (3.) below,
7150  * 2. hooks that both access structures allocated by other hooks, and allocate
7151  *    structures that can be later accessed by other hooks (mostly "cloning"
7152  *    hooks),
7153  * 3. hooks that only allocate structures that can be later accessed by other
7154  *    hooks ("allocating" hooks).
7155  *
7156  * Please follow block comment delimiters in the list to keep this order.
7157  */
7158 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7159         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7160         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7161         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7162         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7163
7164         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7165         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7166         LSM_HOOK_INIT(capget, selinux_capget),
7167         LSM_HOOK_INIT(capset, selinux_capset),
7168         LSM_HOOK_INIT(capable, selinux_capable),
7169         LSM_HOOK_INIT(quotactl, selinux_quotactl),
7170         LSM_HOOK_INIT(quota_on, selinux_quota_on),
7171         LSM_HOOK_INIT(syslog, selinux_syslog),
7172         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7173
7174         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7175
7176         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7177         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7178         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7179
7180         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7181         LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7182         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7183         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7184         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7185         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7186         LSM_HOOK_INIT(sb_mount, selinux_mount),
7187         LSM_HOOK_INIT(sb_umount, selinux_umount),
7188         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7189         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7190
7191         LSM_HOOK_INIT(move_mount, selinux_move_mount),
7192
7193         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7194         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7195
7196         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7197         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7198         LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7199         LSM_HOOK_INIT(inode_create, selinux_inode_create),
7200         LSM_HOOK_INIT(inode_link, selinux_inode_link),
7201         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7202         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7203         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7204         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7205         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7206         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7207         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7208         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7209         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7210         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7211         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7212         LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap),
7213         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7214         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7215         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7216         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7217         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7218         LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7219         LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7220         LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7221         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7222         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7223         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7224         LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop),
7225         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7226         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7227         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7228
7229         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7230
7231         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7232         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7233         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7234         LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7235         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7236         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7237         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7238         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7239         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7240         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7241         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7242         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7243
7244         LSM_HOOK_INIT(file_open, selinux_file_open),
7245
7246         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7247         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7248         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7249         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7250         LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop),
7251         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7252         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7253         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7254         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7255         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7256         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7257         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7258         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7259         LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj),
7260         LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj),
7261         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7262         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7263         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7264         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7265         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7266         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7267         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7268         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7269         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7270         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7271         LSM_HOOK_INIT(userns_create, selinux_userns_create),
7272
7273         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7274         LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop),
7275
7276         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7277         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7278         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7279         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7280
7281         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7282         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7283         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7284
7285         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7286         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7287         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7288
7289         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7290
7291         LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7292         LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7293         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7294         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7295
7296         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7297         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7298         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7299         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7300         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7301         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7302
7303         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7304         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7305
7306         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7307         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7308         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7309         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7310         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7311         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7312         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7313         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7314         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7315         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7316         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7317         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7318         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7319         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7320         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7321         LSM_HOOK_INIT(socket_getpeersec_stream,
7322                         selinux_socket_getpeersec_stream),
7323         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7324         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7325         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7326         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7327         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7328         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7329         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7330         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7331         LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7332         LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7333         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7334         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7335         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7336         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7337         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7338         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7339         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7340         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7341         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7342         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7343         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7344 #ifdef CONFIG_SECURITY_INFINIBAND
7345         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7346         LSM_HOOK_INIT(ib_endport_manage_subnet,
7347                       selinux_ib_endport_manage_subnet),
7348 #endif
7349 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7350         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7351         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7352         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7353         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7354         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7355         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7356                         selinux_xfrm_state_pol_flow_match),
7357         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7358 #endif
7359
7360 #ifdef CONFIG_KEYS
7361         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7362         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7363 #ifdef CONFIG_KEY_NOTIFICATIONS
7364         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7365 #endif
7366 #endif
7367
7368 #ifdef CONFIG_AUDIT
7369         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7370         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7371         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7372 #endif
7373
7374 #ifdef CONFIG_BPF_SYSCALL
7375         LSM_HOOK_INIT(bpf, selinux_bpf),
7376         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7377         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7378         LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7379         LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7380         LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7381 #endif
7382
7383 #ifdef CONFIG_PERF_EVENTS
7384         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7385         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7386         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7387 #endif
7388
7389 #ifdef CONFIG_IO_URING
7390         LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7391         LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7392         LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7393 #endif
7394
7395         /*
7396          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7397          */
7398         LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7399         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7400         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7401         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7402 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7403         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7404 #endif
7405
7406         /*
7407          * PUT "ALLOCATING" HOOKS HERE
7408          */
7409         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7410         LSM_HOOK_INIT(msg_queue_alloc_security,
7411                       selinux_msg_queue_alloc_security),
7412         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7413         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7414         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7415         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7416         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7417         LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx),
7418         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7419         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7420         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7421 #ifdef CONFIG_SECURITY_INFINIBAND
7422         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7423 #endif
7424 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7425         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7426         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7427         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7428                       selinux_xfrm_state_alloc_acquire),
7429 #endif
7430 #ifdef CONFIG_KEYS
7431         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7432 #endif
7433 #ifdef CONFIG_AUDIT
7434         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7435 #endif
7436 #ifdef CONFIG_BPF_SYSCALL
7437         LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7438         LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7439         LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7440 #endif
7441 #ifdef CONFIG_PERF_EVENTS
7442         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7443 #endif
7444 };
7445
7446 static __init int selinux_init(void)
7447 {
7448         pr_info("SELinux:  Initializing.\n");
7449
7450         memset(&selinux_state, 0, sizeof(selinux_state));
7451         enforcing_set(selinux_enforcing_boot);
7452         selinux_avc_init();
7453         mutex_init(&selinux_state.status_lock);
7454         mutex_init(&selinux_state.policy_mutex);
7455
7456         /* Set the security state for the initial task. */
7457         cred_init_security();
7458
7459         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7460         if (!default_noexec)
7461                 pr_notice("SELinux:  virtual memory is executable by default\n");
7462
7463         avc_init();
7464
7465         avtab_cache_init();
7466
7467         ebitmap_cache_init();
7468
7469         hashtab_cache_init();
7470
7471         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7472                            &selinux_lsmid);
7473
7474         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7475                 panic("SELinux: Unable to register AVC netcache callback\n");
7476
7477         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7478                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7479
7480         if (selinux_enforcing_boot)
7481                 pr_debug("SELinux:  Starting in enforcing mode\n");
7482         else
7483                 pr_debug("SELinux:  Starting in permissive mode\n");
7484
7485         fs_validate_description("selinux", selinux_fs_parameters);
7486
7487         return 0;
7488 }
7489
7490 static void delayed_superblock_init(struct super_block *sb, void *unused)
7491 {
7492         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7493 }
7494
7495 void selinux_complete_init(void)
7496 {
7497         pr_debug("SELinux:  Completing initialization.\n");
7498
7499         /* Set up any superblocks initialized prior to the policy load. */
7500         pr_debug("SELinux:  Setting up existing superblocks.\n");
7501         iterate_supers(delayed_superblock_init, NULL);
7502 }
7503
7504 /* SELinux requires early initialization in order to label
7505    all processes and objects when they are created. */
7506 DEFINE_LSM(selinux) = {
7507         .name = "selinux",
7508         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7509         .enabled = &selinux_enabled_boot,
7510         .blobs = &selinux_blob_sizes,
7511         .init = selinux_init,
7512 };
7513
7514 #if defined(CONFIG_NETFILTER)
7515 static const struct nf_hook_ops selinux_nf_ops[] = {
7516         {
7517                 .hook =         selinux_ip_postroute,
7518                 .pf =           NFPROTO_IPV4,
7519                 .hooknum =      NF_INET_POST_ROUTING,
7520                 .priority =     NF_IP_PRI_SELINUX_LAST,
7521         },
7522         {
7523                 .hook =         selinux_ip_forward,
7524                 .pf =           NFPROTO_IPV4,
7525                 .hooknum =      NF_INET_FORWARD,
7526                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7527         },
7528         {
7529                 .hook =         selinux_ip_output,
7530                 .pf =           NFPROTO_IPV4,
7531                 .hooknum =      NF_INET_LOCAL_OUT,
7532                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7533         },
7534 #if IS_ENABLED(CONFIG_IPV6)
7535         {
7536                 .hook =         selinux_ip_postroute,
7537                 .pf =           NFPROTO_IPV6,
7538                 .hooknum =      NF_INET_POST_ROUTING,
7539                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7540         },
7541         {
7542                 .hook =         selinux_ip_forward,
7543                 .pf =           NFPROTO_IPV6,
7544                 .hooknum =      NF_INET_FORWARD,
7545                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7546         },
7547         {
7548                 .hook =         selinux_ip_output,
7549                 .pf =           NFPROTO_IPV6,
7550                 .hooknum =      NF_INET_LOCAL_OUT,
7551                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7552         },
7553 #endif  /* IPV6 */
7554 };
7555
7556 static int __net_init selinux_nf_register(struct net *net)
7557 {
7558         return nf_register_net_hooks(net, selinux_nf_ops,
7559                                      ARRAY_SIZE(selinux_nf_ops));
7560 }
7561
7562 static void __net_exit selinux_nf_unregister(struct net *net)
7563 {
7564         nf_unregister_net_hooks(net, selinux_nf_ops,
7565                                 ARRAY_SIZE(selinux_nf_ops));
7566 }
7567
7568 static struct pernet_operations selinux_net_ops = {
7569         .init = selinux_nf_register,
7570         .exit = selinux_nf_unregister,
7571 };
7572
7573 static int __init selinux_nf_ip_init(void)
7574 {
7575         int err;
7576
7577         if (!selinux_enabled_boot)
7578                 return 0;
7579
7580         pr_debug("SELinux:  Registering netfilter hooks\n");
7581
7582         err = register_pernet_subsys(&selinux_net_ops);
7583         if (err)
7584                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7585
7586         return 0;
7587 }
7588 __initcall(selinux_nf_ip_init);
7589 #endif /* CONFIG_NETFILTER */
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