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[J-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         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, void **ctx,
2873                                         u32 *ctxlen)
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         return security_sid_to_context(newsid, (char **)ctx,
2889                                        ctxlen);
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_CLOSE_NOWRITE))
3408                 perm |= FILE__WATCH_READS;
3409
3410         return path_has_perm(current_cred(), path, perm);
3411 }
3412
3413 /*
3414  * Copy the inode security context value to the user.
3415  *
3416  * Permission check is handled by selinux_inode_getxattr hook.
3417  */
3418 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3419                                      struct inode *inode, const char *name,
3420                                      void **buffer, bool alloc)
3421 {
3422         u32 size;
3423         int error;
3424         char *context = NULL;
3425         struct inode_security_struct *isec;
3426
3427         /*
3428          * If we're not initialized yet, then we can't validate contexts, so
3429          * just let vfs_getxattr fall back to using the on-disk xattr.
3430          */
3431         if (!selinux_initialized() ||
3432             strcmp(name, XATTR_SELINUX_SUFFIX))
3433                 return -EOPNOTSUPP;
3434
3435         /*
3436          * If the caller has CAP_MAC_ADMIN, then get the raw context
3437          * value even if it is not defined by current policy; otherwise,
3438          * use the in-core value under current policy.
3439          * Use the non-auditing forms of the permission checks since
3440          * getxattr may be called by unprivileged processes commonly
3441          * and lack of permission just means that we fall back to the
3442          * in-core context value, not a denial.
3443          */
3444         isec = inode_security(inode);
3445         if (has_cap_mac_admin(false))
3446                 error = security_sid_to_context_force(isec->sid, &context,
3447                                                       &size);
3448         else
3449                 error = security_sid_to_context(isec->sid,
3450                                                 &context, &size);
3451         if (error)
3452                 return error;
3453         error = size;
3454         if (alloc) {
3455                 *buffer = context;
3456                 goto out_nofree;
3457         }
3458         kfree(context);
3459 out_nofree:
3460         return error;
3461 }
3462
3463 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3464                                      const void *value, size_t size, int flags)
3465 {
3466         struct inode_security_struct *isec = inode_security_novalidate(inode);
3467         struct superblock_security_struct *sbsec;
3468         u32 newsid;
3469         int rc;
3470
3471         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3472                 return -EOPNOTSUPP;
3473
3474         sbsec = selinux_superblock(inode->i_sb);
3475         if (!(sbsec->flags & SBLABEL_MNT))
3476                 return -EOPNOTSUPP;
3477
3478         if (!value || !size)
3479                 return -EACCES;
3480
3481         rc = security_context_to_sid(value, size, &newsid,
3482                                      GFP_KERNEL);
3483         if (rc)
3484                 return rc;
3485
3486         spin_lock(&isec->lock);
3487         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3488         isec->sid = newsid;
3489         isec->initialized = LABEL_INITIALIZED;
3490         spin_unlock(&isec->lock);
3491         return 0;
3492 }
3493
3494 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3495 {
3496         const int len = sizeof(XATTR_NAME_SELINUX);
3497
3498         if (!selinux_initialized())
3499                 return 0;
3500
3501         if (buffer && len <= buffer_size)
3502                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3503         return len;
3504 }
3505
3506 static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
3507 {
3508         struct inode_security_struct *isec = inode_security_novalidate(inode);
3509
3510         prop->selinux.secid = isec->sid;
3511 }
3512
3513 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3514 {
3515         struct lsm_prop prop;
3516         struct task_security_struct *tsec;
3517         struct cred *new_creds = *new;
3518
3519         if (new_creds == NULL) {
3520                 new_creds = prepare_creds();
3521                 if (!new_creds)
3522                         return -ENOMEM;
3523         }
3524
3525         tsec = selinux_cred(new_creds);
3526         /* Get label from overlay inode and set it in create_sid */
3527         selinux_inode_getlsmprop(d_inode(src), &prop);
3528         tsec->create_sid = prop.selinux.secid;
3529         *new = new_creds;
3530         return 0;
3531 }
3532
3533 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name)
3534 {
3535         /* The copy_up hook above sets the initial context on an inode, but we
3536          * don't then want to overwrite it by blindly copying all the lower
3537          * xattrs up.  Instead, filter out SELinux-related xattrs following
3538          * policy load.
3539          */
3540         if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX))
3541                 return -ECANCELED; /* Discard */
3542         /*
3543          * Any other attribute apart from SELINUX is not claimed, supported
3544          * by selinux.
3545          */
3546         return -EOPNOTSUPP;
3547 }
3548
3549 /* kernfs node operations */
3550
3551 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3552                                         struct kernfs_node *kn)
3553 {
3554         const struct task_security_struct *tsec = selinux_cred(current_cred());
3555         u32 parent_sid, newsid, clen;
3556         int rc;
3557         char *context;
3558
3559         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3560         if (rc == -ENODATA)
3561                 return 0;
3562         else if (rc < 0)
3563                 return rc;
3564
3565         clen = (u32)rc;
3566         context = kmalloc(clen, GFP_KERNEL);
3567         if (!context)
3568                 return -ENOMEM;
3569
3570         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3571         if (rc < 0) {
3572                 kfree(context);
3573                 return rc;
3574         }
3575
3576         rc = security_context_to_sid(context, clen, &parent_sid,
3577                                      GFP_KERNEL);
3578         kfree(context);
3579         if (rc)
3580                 return rc;
3581
3582         if (tsec->create_sid) {
3583                 newsid = tsec->create_sid;
3584         } else {
3585                 u16 secclass = inode_mode_to_security_class(kn->mode);
3586                 struct qstr q;
3587
3588                 q.name = kn->name;
3589                 q.hash_len = hashlen_string(kn_dir, kn->name);
3590
3591                 rc = security_transition_sid(tsec->sid,
3592                                              parent_sid, secclass, &q,
3593                                              &newsid);
3594                 if (rc)
3595                         return rc;
3596         }
3597
3598         rc = security_sid_to_context_force(newsid,
3599                                            &context, &clen);
3600         if (rc)
3601                 return rc;
3602
3603         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3604                               XATTR_CREATE);
3605         kfree(context);
3606         return rc;
3607 }
3608
3609
3610 /* file security operations */
3611
3612 static int selinux_revalidate_file_permission(struct file *file, int mask)
3613 {
3614         const struct cred *cred = current_cred();
3615         struct inode *inode = file_inode(file);
3616
3617         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3618         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3619                 mask |= MAY_APPEND;
3620
3621         return file_has_perm(cred, file,
3622                              file_mask_to_av(inode->i_mode, mask));
3623 }
3624
3625 static int selinux_file_permission(struct file *file, int mask)
3626 {
3627         struct inode *inode = file_inode(file);
3628         struct file_security_struct *fsec = selinux_file(file);
3629         struct inode_security_struct *isec;
3630         u32 sid = current_sid();
3631
3632         if (!mask)
3633                 /* No permission to check.  Existence test. */
3634                 return 0;
3635
3636         isec = inode_security(inode);
3637         if (sid == fsec->sid && fsec->isid == isec->sid &&
3638             fsec->pseqno == avc_policy_seqno())
3639                 /* No change since file_open check. */
3640                 return 0;
3641
3642         return selinux_revalidate_file_permission(file, mask);
3643 }
3644
3645 static int selinux_file_alloc_security(struct file *file)
3646 {
3647         struct file_security_struct *fsec = selinux_file(file);
3648         u32 sid = current_sid();
3649
3650         fsec->sid = sid;
3651         fsec->fown_sid = sid;
3652
3653         return 0;
3654 }
3655
3656 /*
3657  * Check whether a task has the ioctl permission and cmd
3658  * operation to an inode.
3659  */
3660 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3661                 u32 requested, u16 cmd)
3662 {
3663         struct common_audit_data ad;
3664         struct file_security_struct *fsec = selinux_file(file);
3665         struct inode *inode = file_inode(file);
3666         struct inode_security_struct *isec;
3667         struct lsm_ioctlop_audit ioctl;
3668         u32 ssid = cred_sid(cred);
3669         int rc;
3670         u8 driver = cmd >> 8;
3671         u8 xperm = cmd & 0xff;
3672
3673         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3674         ad.u.op = &ioctl;
3675         ad.u.op->cmd = cmd;
3676         ad.u.op->path = file->f_path;
3677
3678         if (ssid != fsec->sid) {
3679                 rc = avc_has_perm(ssid, fsec->sid,
3680                                 SECCLASS_FD,
3681                                 FD__USE,
3682                                 &ad);
3683                 if (rc)
3684                         goto out;
3685         }
3686
3687         if (unlikely(IS_PRIVATE(inode)))
3688                 return 0;
3689
3690         isec = inode_security(inode);
3691         rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3692                                     requested, driver, xperm, &ad);
3693 out:
3694         return rc;
3695 }
3696
3697 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3698                               unsigned long arg)
3699 {
3700         const struct cred *cred = current_cred();
3701         int error = 0;
3702
3703         switch (cmd) {
3704         case FIONREAD:
3705         case FIBMAP:
3706         case FIGETBSZ:
3707         case FS_IOC_GETFLAGS:
3708         case FS_IOC_GETVERSION:
3709                 error = file_has_perm(cred, file, FILE__GETATTR);
3710                 break;
3711
3712         case FS_IOC_SETFLAGS:
3713         case FS_IOC_SETVERSION:
3714                 error = file_has_perm(cred, file, FILE__SETATTR);
3715                 break;
3716
3717         /* sys_ioctl() checks */
3718         case FIONBIO:
3719         case FIOASYNC:
3720                 error = file_has_perm(cred, file, 0);
3721                 break;
3722
3723         case KDSKBENT:
3724         case KDSKBSENT:
3725                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3726                                             CAP_OPT_NONE, true);
3727                 break;
3728
3729         case FIOCLEX:
3730         case FIONCLEX:
3731                 if (!selinux_policycap_ioctl_skip_cloexec())
3732                         error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3733                 break;
3734
3735         /* default case assumes that the command will go
3736          * to the file's ioctl() function.
3737          */
3738         default:
3739                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3740         }
3741         return error;
3742 }
3743
3744 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3745                               unsigned long arg)
3746 {
3747         /*
3748          * If we are in a 64-bit kernel running 32-bit userspace, we need to
3749          * make sure we don't compare 32-bit flags to 64-bit flags.
3750          */
3751         switch (cmd) {
3752         case FS_IOC32_GETFLAGS:
3753                 cmd = FS_IOC_GETFLAGS;
3754                 break;
3755         case FS_IOC32_SETFLAGS:
3756                 cmd = FS_IOC_SETFLAGS;
3757                 break;
3758         case FS_IOC32_GETVERSION:
3759                 cmd = FS_IOC_GETVERSION;
3760                 break;
3761         case FS_IOC32_SETVERSION:
3762                 cmd = FS_IOC_SETVERSION;
3763                 break;
3764         default:
3765                 break;
3766         }
3767
3768         return selinux_file_ioctl(file, cmd, arg);
3769 }
3770
3771 static int default_noexec __ro_after_init;
3772
3773 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3774 {
3775         const struct cred *cred = current_cred();
3776         u32 sid = cred_sid(cred);
3777         int rc = 0;
3778
3779         if (default_noexec &&
3780             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3781                                    (!shared && (prot & PROT_WRITE)))) {
3782                 /*
3783                  * We are making executable an anonymous mapping or a
3784                  * private file mapping that will also be writable.
3785                  * This has an additional check.
3786                  */
3787                 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3788                                   PROCESS__EXECMEM, NULL);
3789                 if (rc)
3790                         goto error;
3791         }
3792
3793         if (file) {
3794                 /* read access is always possible with a mapping */
3795                 u32 av = FILE__READ;
3796
3797                 /* write access only matters if the mapping is shared */
3798                 if (shared && (prot & PROT_WRITE))
3799                         av |= FILE__WRITE;
3800
3801                 if (prot & PROT_EXEC)
3802                         av |= FILE__EXECUTE;
3803
3804                 return file_has_perm(cred, file, av);
3805         }
3806
3807 error:
3808         return rc;
3809 }
3810
3811 static int selinux_mmap_addr(unsigned long addr)
3812 {
3813         int rc = 0;
3814
3815         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3816                 u32 sid = current_sid();
3817                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3818                                   MEMPROTECT__MMAP_ZERO, NULL);
3819         }
3820
3821         return rc;
3822 }
3823
3824 static int selinux_mmap_file(struct file *file,
3825                              unsigned long reqprot __always_unused,
3826                              unsigned long prot, unsigned long flags)
3827 {
3828         struct common_audit_data ad;
3829         int rc;
3830
3831         if (file) {
3832                 ad.type = LSM_AUDIT_DATA_FILE;
3833                 ad.u.file = file;
3834                 rc = inode_has_perm(current_cred(), file_inode(file),
3835                                     FILE__MAP, &ad);
3836                 if (rc)
3837                         return rc;
3838         }
3839
3840         return file_map_prot_check(file, prot,
3841                                    (flags & MAP_TYPE) == MAP_SHARED);
3842 }
3843
3844 static int selinux_file_mprotect(struct vm_area_struct *vma,
3845                                  unsigned long reqprot __always_unused,
3846                                  unsigned long prot)
3847 {
3848         const struct cred *cred = current_cred();
3849         u32 sid = cred_sid(cred);
3850
3851         if (default_noexec &&
3852             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3853                 int rc = 0;
3854                 /*
3855                  * We don't use the vma_is_initial_heap() helper as it has
3856                  * a history of problems and is currently broken on systems
3857                  * where there is no heap, e.g. brk == start_brk.  Before
3858                  * replacing the conditional below with vma_is_initial_heap(),
3859                  * or something similar, please ensure that the logic is the
3860                  * same as what we have below or you have tested every possible
3861                  * corner case you can think to test.
3862                  */
3863                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3864                     vma->vm_end <= vma->vm_mm->brk) {
3865                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3866                                           PROCESS__EXECHEAP, NULL);
3867                 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3868                             vma_is_stack_for_current(vma))) {
3869                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3870                                           PROCESS__EXECSTACK, NULL);
3871                 } else if (vma->vm_file && vma->anon_vma) {
3872                         /*
3873                          * We are making executable a file mapping that has
3874                          * had some COW done. Since pages might have been
3875                          * written, check ability to execute the possibly
3876                          * modified content.  This typically should only
3877                          * occur for text relocations.
3878                          */
3879                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3880                 }
3881                 if (rc)
3882                         return rc;
3883         }
3884
3885         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3886 }
3887
3888 static int selinux_file_lock(struct file *file, unsigned int cmd)
3889 {
3890         const struct cred *cred = current_cred();
3891
3892         return file_has_perm(cred, file, FILE__LOCK);
3893 }
3894
3895 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3896                               unsigned long arg)
3897 {
3898         const struct cred *cred = current_cred();
3899         int err = 0;
3900
3901         switch (cmd) {
3902         case F_SETFL:
3903                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3904                         err = file_has_perm(cred, file, FILE__WRITE);
3905                         break;
3906                 }
3907                 fallthrough;
3908         case F_SETOWN:
3909         case F_SETSIG:
3910         case F_GETFL:
3911         case F_GETOWN:
3912         case F_GETSIG:
3913         case F_GETOWNER_UIDS:
3914                 /* Just check FD__USE permission */
3915                 err = file_has_perm(cred, file, 0);
3916                 break;
3917         case F_GETLK:
3918         case F_SETLK:
3919         case F_SETLKW:
3920         case F_OFD_GETLK:
3921         case F_OFD_SETLK:
3922         case F_OFD_SETLKW:
3923 #if BITS_PER_LONG == 32
3924         case F_GETLK64:
3925         case F_SETLK64:
3926         case F_SETLKW64:
3927 #endif
3928                 err = file_has_perm(cred, file, FILE__LOCK);
3929                 break;
3930         }
3931
3932         return err;
3933 }
3934
3935 static void selinux_file_set_fowner(struct file *file)
3936 {
3937         struct file_security_struct *fsec;
3938
3939         fsec = selinux_file(file);
3940         fsec->fown_sid = current_sid();
3941 }
3942
3943 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3944                                        struct fown_struct *fown, int signum)
3945 {
3946         struct file *file;
3947         u32 sid = task_sid_obj(tsk);
3948         u32 perm;
3949         struct file_security_struct *fsec;
3950
3951         /* struct fown_struct is never outside the context of a struct file */
3952         file = fown->file;
3953
3954         fsec = selinux_file(file);
3955
3956         if (!signum)
3957                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3958         else
3959                 perm = signal_to_av(signum);
3960
3961         return avc_has_perm(fsec->fown_sid, sid,
3962                             SECCLASS_PROCESS, perm, NULL);
3963 }
3964
3965 static int selinux_file_receive(struct file *file)
3966 {
3967         const struct cred *cred = current_cred();
3968
3969         return file_has_perm(cred, file, file_to_av(file));
3970 }
3971
3972 static int selinux_file_open(struct file *file)
3973 {
3974         struct file_security_struct *fsec;
3975         struct inode_security_struct *isec;
3976
3977         fsec = selinux_file(file);
3978         isec = inode_security(file_inode(file));
3979         /*
3980          * Save inode label and policy sequence number
3981          * at open-time so that selinux_file_permission
3982          * can determine whether revalidation is necessary.
3983          * Task label is already saved in the file security
3984          * struct as its SID.
3985          */
3986         fsec->isid = isec->sid;
3987         fsec->pseqno = avc_policy_seqno();
3988         /*
3989          * Since the inode label or policy seqno may have changed
3990          * between the selinux_inode_permission check and the saving
3991          * of state above, recheck that access is still permitted.
3992          * Otherwise, access might never be revalidated against the
3993          * new inode label or new policy.
3994          * This check is not redundant - do not remove.
3995          */
3996         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3997 }
3998
3999 /* task security operations */
4000
4001 static int selinux_task_alloc(struct task_struct *task,
4002                               unsigned long clone_flags)
4003 {
4004         u32 sid = current_sid();
4005
4006         return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4007 }
4008
4009 /*
4010  * prepare a new set of credentials for modification
4011  */
4012 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4013                                 gfp_t gfp)
4014 {
4015         const struct task_security_struct *old_tsec = selinux_cred(old);
4016         struct task_security_struct *tsec = selinux_cred(new);
4017
4018         *tsec = *old_tsec;
4019         return 0;
4020 }
4021
4022 /*
4023  * transfer the SELinux data to a blank set of creds
4024  */
4025 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4026 {
4027         const struct task_security_struct *old_tsec = selinux_cred(old);
4028         struct task_security_struct *tsec = selinux_cred(new);
4029
4030         *tsec = *old_tsec;
4031 }
4032
4033 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4034 {
4035         *secid = cred_sid(c);
4036 }
4037
4038 static void selinux_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
4039 {
4040         prop->selinux.secid = cred_sid(c);
4041 }
4042
4043 /*
4044  * set the security data for a kernel service
4045  * - all the creation contexts are set to unlabelled
4046  */
4047 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4048 {
4049         struct task_security_struct *tsec = selinux_cred(new);
4050         u32 sid = current_sid();
4051         int ret;
4052
4053         ret = avc_has_perm(sid, secid,
4054                            SECCLASS_KERNEL_SERVICE,
4055                            KERNEL_SERVICE__USE_AS_OVERRIDE,
4056                            NULL);
4057         if (ret == 0) {
4058                 tsec->sid = secid;
4059                 tsec->create_sid = 0;
4060                 tsec->keycreate_sid = 0;
4061                 tsec->sockcreate_sid = 0;
4062         }
4063         return ret;
4064 }
4065
4066 /*
4067  * set the file creation context in a security record to the same as the
4068  * objective context of the specified inode
4069  */
4070 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4071 {
4072         struct inode_security_struct *isec = inode_security(inode);
4073         struct task_security_struct *tsec = selinux_cred(new);
4074         u32 sid = current_sid();
4075         int ret;
4076
4077         ret = avc_has_perm(sid, isec->sid,
4078                            SECCLASS_KERNEL_SERVICE,
4079                            KERNEL_SERVICE__CREATE_FILES_AS,
4080                            NULL);
4081
4082         if (ret == 0)
4083                 tsec->create_sid = isec->sid;
4084         return ret;
4085 }
4086
4087 static int selinux_kernel_module_request(char *kmod_name)
4088 {
4089         struct common_audit_data ad;
4090
4091         ad.type = LSM_AUDIT_DATA_KMOD;
4092         ad.u.kmod_name = kmod_name;
4093
4094         return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4095                             SYSTEM__MODULE_REQUEST, &ad);
4096 }
4097
4098 static int selinux_kernel_module_from_file(struct file *file)
4099 {
4100         struct common_audit_data ad;
4101         struct inode_security_struct *isec;
4102         struct file_security_struct *fsec;
4103         u32 sid = current_sid();
4104         int rc;
4105
4106         /* init_module */
4107         if (file == NULL)
4108                 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4109                                         SYSTEM__MODULE_LOAD, NULL);
4110
4111         /* finit_module */
4112
4113         ad.type = LSM_AUDIT_DATA_FILE;
4114         ad.u.file = file;
4115
4116         fsec = selinux_file(file);
4117         if (sid != fsec->sid) {
4118                 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4119                 if (rc)
4120                         return rc;
4121         }
4122
4123         isec = inode_security(file_inode(file));
4124         return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4125                                 SYSTEM__MODULE_LOAD, &ad);
4126 }
4127
4128 static int selinux_kernel_read_file(struct file *file,
4129                                     enum kernel_read_file_id id,
4130                                     bool contents)
4131 {
4132         int rc = 0;
4133
4134         switch (id) {
4135         case READING_MODULE:
4136                 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4137                 break;
4138         default:
4139                 break;
4140         }
4141
4142         return rc;
4143 }
4144
4145 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4146 {
4147         int rc = 0;
4148
4149         switch (id) {
4150         case LOADING_MODULE:
4151                 rc = selinux_kernel_module_from_file(NULL);
4152                 break;
4153         default:
4154                 break;
4155         }
4156
4157         return rc;
4158 }
4159
4160 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4161 {
4162         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4163                             PROCESS__SETPGID, NULL);
4164 }
4165
4166 static int selinux_task_getpgid(struct task_struct *p)
4167 {
4168         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4169                             PROCESS__GETPGID, NULL);
4170 }
4171
4172 static int selinux_task_getsid(struct task_struct *p)
4173 {
4174         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4175                             PROCESS__GETSESSION, NULL);
4176 }
4177
4178 static void selinux_current_getlsmprop_subj(struct lsm_prop *prop)
4179 {
4180         prop->selinux.secid = current_sid();
4181 }
4182
4183 static void selinux_task_getlsmprop_obj(struct task_struct *p,
4184                                         struct lsm_prop *prop)
4185 {
4186         prop->selinux.secid = task_sid_obj(p);
4187 }
4188
4189 static int selinux_task_setnice(struct task_struct *p, int nice)
4190 {
4191         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4192                             PROCESS__SETSCHED, NULL);
4193 }
4194
4195 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4196 {
4197         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4198                             PROCESS__SETSCHED, NULL);
4199 }
4200
4201 static int selinux_task_getioprio(struct task_struct *p)
4202 {
4203         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4204                             PROCESS__GETSCHED, NULL);
4205 }
4206
4207 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4208                                 unsigned int flags)
4209 {
4210         u32 av = 0;
4211
4212         if (!flags)
4213                 return 0;
4214         if (flags & LSM_PRLIMIT_WRITE)
4215                 av |= PROCESS__SETRLIMIT;
4216         if (flags & LSM_PRLIMIT_READ)
4217                 av |= PROCESS__GETRLIMIT;
4218         return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4219                             SECCLASS_PROCESS, av, NULL);
4220 }
4221
4222 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4223                 struct rlimit *new_rlim)
4224 {
4225         struct rlimit *old_rlim = p->signal->rlim + resource;
4226
4227         /* Control the ability to change the hard limit (whether
4228            lowering or raising it), so that the hard limit can
4229            later be used as a safe reset point for the soft limit
4230            upon context transitions.  See selinux_bprm_committing_creds. */
4231         if (old_rlim->rlim_max != new_rlim->rlim_max)
4232                 return avc_has_perm(current_sid(), task_sid_obj(p),
4233                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4234
4235         return 0;
4236 }
4237
4238 static int selinux_task_setscheduler(struct task_struct *p)
4239 {
4240         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4241                             PROCESS__SETSCHED, NULL);
4242 }
4243
4244 static int selinux_task_getscheduler(struct task_struct *p)
4245 {
4246         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4247                             PROCESS__GETSCHED, NULL);
4248 }
4249
4250 static int selinux_task_movememory(struct task_struct *p)
4251 {
4252         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4253                             PROCESS__SETSCHED, NULL);
4254 }
4255
4256 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4257                                 int sig, const struct cred *cred)
4258 {
4259         u32 secid;
4260         u32 perm;
4261
4262         if (!sig)
4263                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4264         else
4265                 perm = signal_to_av(sig);
4266         if (!cred)
4267                 secid = current_sid();
4268         else
4269                 secid = cred_sid(cred);
4270         return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4271 }
4272
4273 static void selinux_task_to_inode(struct task_struct *p,
4274                                   struct inode *inode)
4275 {
4276         struct inode_security_struct *isec = selinux_inode(inode);
4277         u32 sid = task_sid_obj(p);
4278
4279         spin_lock(&isec->lock);
4280         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4281         isec->sid = sid;
4282         isec->initialized = LABEL_INITIALIZED;
4283         spin_unlock(&isec->lock);
4284 }
4285
4286 static int selinux_userns_create(const struct cred *cred)
4287 {
4288         u32 sid = current_sid();
4289
4290         return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4291                         USER_NAMESPACE__CREATE, NULL);
4292 }
4293
4294 /* Returns error only if unable to parse addresses */
4295 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4296                         struct common_audit_data *ad, u8 *proto)
4297 {
4298         int offset, ihlen, ret = -EINVAL;
4299         struct iphdr _iph, *ih;
4300
4301         offset = skb_network_offset(skb);
4302         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4303         if (ih == NULL)
4304                 goto out;
4305
4306         ihlen = ih->ihl * 4;
4307         if (ihlen < sizeof(_iph))
4308                 goto out;
4309
4310         ad->u.net->v4info.saddr = ih->saddr;
4311         ad->u.net->v4info.daddr = ih->daddr;
4312         ret = 0;
4313
4314         if (proto)
4315                 *proto = ih->protocol;
4316
4317         switch (ih->protocol) {
4318         case IPPROTO_TCP: {
4319                 struct tcphdr _tcph, *th;
4320
4321                 if (ntohs(ih->frag_off) & IP_OFFSET)
4322                         break;
4323
4324                 offset += ihlen;
4325                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4326                 if (th == NULL)
4327                         break;
4328
4329                 ad->u.net->sport = th->source;
4330                 ad->u.net->dport = th->dest;
4331                 break;
4332         }
4333
4334         case IPPROTO_UDP: {
4335                 struct udphdr _udph, *uh;
4336
4337                 if (ntohs(ih->frag_off) & IP_OFFSET)
4338                         break;
4339
4340                 offset += ihlen;
4341                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4342                 if (uh == NULL)
4343                         break;
4344
4345                 ad->u.net->sport = uh->source;
4346                 ad->u.net->dport = uh->dest;
4347                 break;
4348         }
4349
4350         case IPPROTO_DCCP: {
4351                 struct dccp_hdr _dccph, *dh;
4352
4353                 if (ntohs(ih->frag_off) & IP_OFFSET)
4354                         break;
4355
4356                 offset += ihlen;
4357                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4358                 if (dh == NULL)
4359                         break;
4360
4361                 ad->u.net->sport = dh->dccph_sport;
4362                 ad->u.net->dport = dh->dccph_dport;
4363                 break;
4364         }
4365
4366 #if IS_ENABLED(CONFIG_IP_SCTP)
4367         case IPPROTO_SCTP: {
4368                 struct sctphdr _sctph, *sh;
4369
4370                 if (ntohs(ih->frag_off) & IP_OFFSET)
4371                         break;
4372
4373                 offset += ihlen;
4374                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4375                 if (sh == NULL)
4376                         break;
4377
4378                 ad->u.net->sport = sh->source;
4379                 ad->u.net->dport = sh->dest;
4380                 break;
4381         }
4382 #endif
4383         default:
4384                 break;
4385         }
4386 out:
4387         return ret;
4388 }
4389
4390 #if IS_ENABLED(CONFIG_IPV6)
4391
4392 /* Returns error only if unable to parse addresses */
4393 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4394                         struct common_audit_data *ad, u8 *proto)
4395 {
4396         u8 nexthdr;
4397         int ret = -EINVAL, offset;
4398         struct ipv6hdr _ipv6h, *ip6;
4399         __be16 frag_off;
4400
4401         offset = skb_network_offset(skb);
4402         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4403         if (ip6 == NULL)
4404                 goto out;
4405
4406         ad->u.net->v6info.saddr = ip6->saddr;
4407         ad->u.net->v6info.daddr = ip6->daddr;
4408         ret = 0;
4409
4410         nexthdr = ip6->nexthdr;
4411         offset += sizeof(_ipv6h);
4412         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4413         if (offset < 0)
4414                 goto out;
4415
4416         if (proto)
4417                 *proto = nexthdr;
4418
4419         switch (nexthdr) {
4420         case IPPROTO_TCP: {
4421                 struct tcphdr _tcph, *th;
4422
4423                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4424                 if (th == NULL)
4425                         break;
4426
4427                 ad->u.net->sport = th->source;
4428                 ad->u.net->dport = th->dest;
4429                 break;
4430         }
4431
4432         case IPPROTO_UDP: {
4433                 struct udphdr _udph, *uh;
4434
4435                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4436                 if (uh == NULL)
4437                         break;
4438
4439                 ad->u.net->sport = uh->source;
4440                 ad->u.net->dport = uh->dest;
4441                 break;
4442         }
4443
4444         case IPPROTO_DCCP: {
4445                 struct dccp_hdr _dccph, *dh;
4446
4447                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4448                 if (dh == NULL)
4449                         break;
4450
4451                 ad->u.net->sport = dh->dccph_sport;
4452                 ad->u.net->dport = dh->dccph_dport;
4453                 break;
4454         }
4455
4456 #if IS_ENABLED(CONFIG_IP_SCTP)
4457         case IPPROTO_SCTP: {
4458                 struct sctphdr _sctph, *sh;
4459
4460                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4461                 if (sh == NULL)
4462                         break;
4463
4464                 ad->u.net->sport = sh->source;
4465                 ad->u.net->dport = sh->dest;
4466                 break;
4467         }
4468 #endif
4469         /* includes fragments */
4470         default:
4471                 break;
4472         }
4473 out:
4474         return ret;
4475 }
4476
4477 #endif /* IPV6 */
4478
4479 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4480                              char **_addrp, int src, u8 *proto)
4481 {
4482         char *addrp;
4483         int ret;
4484
4485         switch (ad->u.net->family) {
4486         case PF_INET:
4487                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4488                 if (ret)
4489                         goto parse_error;
4490                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4491                                        &ad->u.net->v4info.daddr);
4492                 goto okay;
4493
4494 #if IS_ENABLED(CONFIG_IPV6)
4495         case PF_INET6:
4496                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4497                 if (ret)
4498                         goto parse_error;
4499                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4500                                        &ad->u.net->v6info.daddr);
4501                 goto okay;
4502 #endif  /* IPV6 */
4503         default:
4504                 addrp = NULL;
4505                 goto okay;
4506         }
4507
4508 parse_error:
4509         pr_warn(
4510                "SELinux: failure in selinux_parse_skb(),"
4511                " unable to parse packet\n");
4512         return ret;
4513
4514 okay:
4515         if (_addrp)
4516                 *_addrp = addrp;
4517         return 0;
4518 }
4519
4520 /**
4521  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4522  * @skb: the packet
4523  * @family: protocol family
4524  * @sid: the packet's peer label SID
4525  *
4526  * Description:
4527  * Check the various different forms of network peer labeling and determine
4528  * the peer label/SID for the packet; most of the magic actually occurs in
4529  * the security server function security_net_peersid_cmp().  The function
4530  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4531  * or -EACCES if @sid is invalid due to inconsistencies with the different
4532  * peer labels.
4533  *
4534  */
4535 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4536 {
4537         int err;
4538         u32 xfrm_sid;
4539         u32 nlbl_sid;
4540         u32 nlbl_type;
4541
4542         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4543         if (unlikely(err))
4544                 return -EACCES;
4545         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4546         if (unlikely(err))
4547                 return -EACCES;
4548
4549         err = security_net_peersid_resolve(nlbl_sid,
4550                                            nlbl_type, xfrm_sid, sid);
4551         if (unlikely(err)) {
4552                 pr_warn(
4553                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4554                        " unable to determine packet's peer label\n");
4555                 return -EACCES;
4556         }
4557
4558         return 0;
4559 }
4560
4561 /**
4562  * selinux_conn_sid - Determine the child socket label for a connection
4563  * @sk_sid: the parent socket's SID
4564  * @skb_sid: the packet's SID
4565  * @conn_sid: the resulting connection SID
4566  *
4567  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4568  * combined with the MLS information from @skb_sid in order to create
4569  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4570  * of @sk_sid.  Returns zero on success, negative values on failure.
4571  *
4572  */
4573 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4574 {
4575         int err = 0;
4576
4577         if (skb_sid != SECSID_NULL)
4578                 err = security_sid_mls_copy(sk_sid, skb_sid,
4579                                             conn_sid);
4580         else
4581                 *conn_sid = sk_sid;
4582
4583         return err;
4584 }
4585
4586 /* socket security operations */
4587
4588 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4589                                  u16 secclass, u32 *socksid)
4590 {
4591         if (tsec->sockcreate_sid > SECSID_NULL) {
4592                 *socksid = tsec->sockcreate_sid;
4593                 return 0;
4594         }
4595
4596         return security_transition_sid(tsec->sid, tsec->sid,
4597                                        secclass, NULL, socksid);
4598 }
4599
4600 static bool sock_skip_has_perm(u32 sid)
4601 {
4602         if (sid == SECINITSID_KERNEL)
4603                 return true;
4604
4605         /*
4606          * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4607          * inherited the kernel context from early boot used to be skipped
4608          * here, so preserve that behavior unless the capability is set.
4609          *
4610          * By setting the capability the policy signals that it is ready
4611          * for this quirk to be fixed. Note that sockets created by a kernel
4612          * thread or a usermode helper executed without a transition will
4613          * still be skipped in this check regardless of the policycap
4614          * setting.
4615          */
4616         if (!selinux_policycap_userspace_initial_context() &&
4617             sid == SECINITSID_INIT)
4618                 return true;
4619         return false;
4620 }
4621
4622
4623 static int sock_has_perm(struct sock *sk, u32 perms)
4624 {
4625         struct sk_security_struct *sksec = sk->sk_security;
4626         struct common_audit_data ad;
4627         struct lsm_network_audit net;
4628
4629         if (sock_skip_has_perm(sksec->sid))
4630                 return 0;
4631
4632         ad_net_init_from_sk(&ad, &net, sk);
4633
4634         return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4635                             &ad);
4636 }
4637
4638 static int selinux_socket_create(int family, int type,
4639                                  int protocol, int kern)
4640 {
4641         const struct task_security_struct *tsec = selinux_cred(current_cred());
4642         u32 newsid;
4643         u16 secclass;
4644         int rc;
4645
4646         if (kern)
4647                 return 0;
4648
4649         secclass = socket_type_to_security_class(family, type, protocol);
4650         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4651         if (rc)
4652                 return rc;
4653
4654         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4655 }
4656
4657 static int selinux_socket_post_create(struct socket *sock, int family,
4658                                       int type, int protocol, int kern)
4659 {
4660         const struct task_security_struct *tsec = selinux_cred(current_cred());
4661         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4662         struct sk_security_struct *sksec;
4663         u16 sclass = socket_type_to_security_class(family, type, protocol);
4664         u32 sid = SECINITSID_KERNEL;
4665         int err = 0;
4666
4667         if (!kern) {
4668                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4669                 if (err)
4670                         return err;
4671         }
4672
4673         isec->sclass = sclass;
4674         isec->sid = sid;
4675         isec->initialized = LABEL_INITIALIZED;
4676
4677         if (sock->sk) {
4678                 sksec = selinux_sock(sock->sk);
4679                 sksec->sclass = sclass;
4680                 sksec->sid = sid;
4681                 /* Allows detection of the first association on this socket */
4682                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4683                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4684
4685                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4686         }
4687
4688         return err;
4689 }
4690
4691 static int selinux_socket_socketpair(struct socket *socka,
4692                                      struct socket *sockb)
4693 {
4694         struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
4695         struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
4696
4697         sksec_a->peer_sid = sksec_b->sid;
4698         sksec_b->peer_sid = sksec_a->sid;
4699
4700         return 0;
4701 }
4702
4703 /* Range of port numbers used to automatically bind.
4704    Need to determine whether we should perform a name_bind
4705    permission check between the socket and the port number. */
4706
4707 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4708 {
4709         struct sock *sk = sock->sk;
4710         struct sk_security_struct *sksec = selinux_sock(sk);
4711         u16 family;
4712         int err;
4713
4714         err = sock_has_perm(sk, SOCKET__BIND);
4715         if (err)
4716                 goto out;
4717
4718         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4719         family = sk->sk_family;
4720         if (family == PF_INET || family == PF_INET6) {
4721                 char *addrp;
4722                 struct common_audit_data ad;
4723                 struct lsm_network_audit net = {0,};
4724                 struct sockaddr_in *addr4 = NULL;
4725                 struct sockaddr_in6 *addr6 = NULL;
4726                 u16 family_sa;
4727                 unsigned short snum;
4728                 u32 sid, node_perm;
4729
4730                 /*
4731                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4732                  * that validates multiple binding addresses. Because of this
4733                  * need to check address->sa_family as it is possible to have
4734                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4735                  */
4736                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4737                         return -EINVAL;
4738                 family_sa = address->sa_family;
4739                 switch (family_sa) {
4740                 case AF_UNSPEC:
4741                 case AF_INET:
4742                         if (addrlen < sizeof(struct sockaddr_in))
4743                                 return -EINVAL;
4744                         addr4 = (struct sockaddr_in *)address;
4745                         if (family_sa == AF_UNSPEC) {
4746                                 if (family == PF_INET6) {
4747                                         /* Length check from inet6_bind_sk() */
4748                                         if (addrlen < SIN6_LEN_RFC2133)
4749                                                 return -EINVAL;
4750                                         /* Family check from __inet6_bind() */
4751                                         goto err_af;
4752                                 }
4753                                 /* see __inet_bind(), we only want to allow
4754                                  * AF_UNSPEC if the address is INADDR_ANY
4755                                  */
4756                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4757                                         goto err_af;
4758                                 family_sa = AF_INET;
4759                         }
4760                         snum = ntohs(addr4->sin_port);
4761                         addrp = (char *)&addr4->sin_addr.s_addr;
4762                         break;
4763                 case AF_INET6:
4764                         if (addrlen < SIN6_LEN_RFC2133)
4765                                 return -EINVAL;
4766                         addr6 = (struct sockaddr_in6 *)address;
4767                         snum = ntohs(addr6->sin6_port);
4768                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4769                         break;
4770                 default:
4771                         goto err_af;
4772                 }
4773
4774                 ad.type = LSM_AUDIT_DATA_NET;
4775                 ad.u.net = &net;
4776                 ad.u.net->sport = htons(snum);
4777                 ad.u.net->family = family_sa;
4778
4779                 if (snum) {
4780                         int low, high;
4781
4782                         inet_get_local_port_range(sock_net(sk), &low, &high);
4783
4784                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4785                             snum < low || snum > high) {
4786                                 err = sel_netport_sid(sk->sk_protocol,
4787                                                       snum, &sid);
4788                                 if (err)
4789                                         goto out;
4790                                 err = avc_has_perm(sksec->sid, sid,
4791                                                    sksec->sclass,
4792                                                    SOCKET__NAME_BIND, &ad);
4793                                 if (err)
4794                                         goto out;
4795                         }
4796                 }
4797
4798                 switch (sksec->sclass) {
4799                 case SECCLASS_TCP_SOCKET:
4800                         node_perm = TCP_SOCKET__NODE_BIND;
4801                         break;
4802
4803                 case SECCLASS_UDP_SOCKET:
4804                         node_perm = UDP_SOCKET__NODE_BIND;
4805                         break;
4806
4807                 case SECCLASS_DCCP_SOCKET:
4808                         node_perm = DCCP_SOCKET__NODE_BIND;
4809                         break;
4810
4811                 case SECCLASS_SCTP_SOCKET:
4812                         node_perm = SCTP_SOCKET__NODE_BIND;
4813                         break;
4814
4815                 default:
4816                         node_perm = RAWIP_SOCKET__NODE_BIND;
4817                         break;
4818                 }
4819
4820                 err = sel_netnode_sid(addrp, family_sa, &sid);
4821                 if (err)
4822                         goto out;
4823
4824                 if (family_sa == AF_INET)
4825                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4826                 else
4827                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4828
4829                 err = avc_has_perm(sksec->sid, sid,
4830                                    sksec->sclass, node_perm, &ad);
4831                 if (err)
4832                         goto out;
4833         }
4834 out:
4835         return err;
4836 err_af:
4837         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4838         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4839                 return -EINVAL;
4840         return -EAFNOSUPPORT;
4841 }
4842
4843 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4844  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4845  */
4846 static int selinux_socket_connect_helper(struct socket *sock,
4847                                          struct sockaddr *address, int addrlen)
4848 {
4849         struct sock *sk = sock->sk;
4850         struct sk_security_struct *sksec = selinux_sock(sk);
4851         int err;
4852
4853         err = sock_has_perm(sk, SOCKET__CONNECT);
4854         if (err)
4855                 return err;
4856         if (addrlen < offsetofend(struct sockaddr, sa_family))
4857                 return -EINVAL;
4858
4859         /* connect(AF_UNSPEC) has special handling, as it is a documented
4860          * way to disconnect the socket
4861          */
4862         if (address->sa_family == AF_UNSPEC)
4863                 return 0;
4864
4865         /*
4866          * If a TCP, DCCP or SCTP socket, check name_connect permission
4867          * for the port.
4868          */
4869         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4870             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4871             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4872                 struct common_audit_data ad;
4873                 struct lsm_network_audit net = {0,};
4874                 struct sockaddr_in *addr4 = NULL;
4875                 struct sockaddr_in6 *addr6 = NULL;
4876                 unsigned short snum;
4877                 u32 sid, perm;
4878
4879                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4880                  * that validates multiple connect addresses. Because of this
4881                  * need to check address->sa_family as it is possible to have
4882                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4883                  */
4884                 switch (address->sa_family) {
4885                 case AF_INET:
4886                         addr4 = (struct sockaddr_in *)address;
4887                         if (addrlen < sizeof(struct sockaddr_in))
4888                                 return -EINVAL;
4889                         snum = ntohs(addr4->sin_port);
4890                         break;
4891                 case AF_INET6:
4892                         addr6 = (struct sockaddr_in6 *)address;
4893                         if (addrlen < SIN6_LEN_RFC2133)
4894                                 return -EINVAL;
4895                         snum = ntohs(addr6->sin6_port);
4896                         break;
4897                 default:
4898                         /* Note that SCTP services expect -EINVAL, whereas
4899                          * others expect -EAFNOSUPPORT.
4900                          */
4901                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4902                                 return -EINVAL;
4903                         else
4904                                 return -EAFNOSUPPORT;
4905                 }
4906
4907                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4908                 if (err)
4909                         return err;
4910
4911                 switch (sksec->sclass) {
4912                 case SECCLASS_TCP_SOCKET:
4913                         perm = TCP_SOCKET__NAME_CONNECT;
4914                         break;
4915                 case SECCLASS_DCCP_SOCKET:
4916                         perm = DCCP_SOCKET__NAME_CONNECT;
4917                         break;
4918                 case SECCLASS_SCTP_SOCKET:
4919                         perm = SCTP_SOCKET__NAME_CONNECT;
4920                         break;
4921                 }
4922
4923                 ad.type = LSM_AUDIT_DATA_NET;
4924                 ad.u.net = &net;
4925                 ad.u.net->dport = htons(snum);
4926                 ad.u.net->family = address->sa_family;
4927                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4928                 if (err)
4929                         return err;
4930         }
4931
4932         return 0;
4933 }
4934
4935 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4936 static int selinux_socket_connect(struct socket *sock,
4937                                   struct sockaddr *address, int addrlen)
4938 {
4939         int err;
4940         struct sock *sk = sock->sk;
4941
4942         err = selinux_socket_connect_helper(sock, address, addrlen);
4943         if (err)
4944                 return err;
4945
4946         return selinux_netlbl_socket_connect(sk, address);
4947 }
4948
4949 static int selinux_socket_listen(struct socket *sock, int backlog)
4950 {
4951         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4952 }
4953
4954 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4955 {
4956         int err;
4957         struct inode_security_struct *isec;
4958         struct inode_security_struct *newisec;
4959         u16 sclass;
4960         u32 sid;
4961
4962         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4963         if (err)
4964                 return err;
4965
4966         isec = inode_security_novalidate(SOCK_INODE(sock));
4967         spin_lock(&isec->lock);
4968         sclass = isec->sclass;
4969         sid = isec->sid;
4970         spin_unlock(&isec->lock);
4971
4972         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4973         newisec->sclass = sclass;
4974         newisec->sid = sid;
4975         newisec->initialized = LABEL_INITIALIZED;
4976
4977         return 0;
4978 }
4979
4980 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4981                                   int size)
4982 {
4983         return sock_has_perm(sock->sk, SOCKET__WRITE);
4984 }
4985
4986 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4987                                   int size, int flags)
4988 {
4989         return sock_has_perm(sock->sk, SOCKET__READ);
4990 }
4991
4992 static int selinux_socket_getsockname(struct socket *sock)
4993 {
4994         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4995 }
4996
4997 static int selinux_socket_getpeername(struct socket *sock)
4998 {
4999         return sock_has_perm(sock->sk, SOCKET__GETATTR);
5000 }
5001
5002 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5003 {
5004         int err;
5005
5006         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5007         if (err)
5008                 return err;
5009
5010         return selinux_netlbl_socket_setsockopt(sock, level, optname);
5011 }
5012
5013 static int selinux_socket_getsockopt(struct socket *sock, int level,
5014                                      int optname)
5015 {
5016         return sock_has_perm(sock->sk, SOCKET__GETOPT);
5017 }
5018
5019 static int selinux_socket_shutdown(struct socket *sock, int how)
5020 {
5021         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5022 }
5023
5024 static int selinux_socket_unix_stream_connect(struct sock *sock,
5025                                               struct sock *other,
5026                                               struct sock *newsk)
5027 {
5028         struct sk_security_struct *sksec_sock = selinux_sock(sock);
5029         struct sk_security_struct *sksec_other = selinux_sock(other);
5030         struct sk_security_struct *sksec_new = selinux_sock(newsk);
5031         struct common_audit_data ad;
5032         struct lsm_network_audit net;
5033         int err;
5034
5035         ad_net_init_from_sk(&ad, &net, other);
5036
5037         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5038                            sksec_other->sclass,
5039                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5040         if (err)
5041                 return err;
5042
5043         /* server child socket */
5044         sksec_new->peer_sid = sksec_sock->sid;
5045         err = security_sid_mls_copy(sksec_other->sid,
5046                                     sksec_sock->sid, &sksec_new->sid);
5047         if (err)
5048                 return err;
5049
5050         /* connecting socket */
5051         sksec_sock->peer_sid = sksec_new->sid;
5052
5053         return 0;
5054 }
5055
5056 static int selinux_socket_unix_may_send(struct socket *sock,
5057                                         struct socket *other)
5058 {
5059         struct sk_security_struct *ssec = selinux_sock(sock->sk);
5060         struct sk_security_struct *osec = selinux_sock(other->sk);
5061         struct common_audit_data ad;
5062         struct lsm_network_audit net;
5063
5064         ad_net_init_from_sk(&ad, &net, other->sk);
5065
5066         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5067                             &ad);
5068 }
5069
5070 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5071                                     char *addrp, u16 family, u32 peer_sid,
5072                                     struct common_audit_data *ad)
5073 {
5074         int err;
5075         u32 if_sid;
5076         u32 node_sid;
5077
5078         err = sel_netif_sid(ns, ifindex, &if_sid);
5079         if (err)
5080                 return err;
5081         err = avc_has_perm(peer_sid, if_sid,
5082                            SECCLASS_NETIF, NETIF__INGRESS, ad);
5083         if (err)
5084                 return err;
5085
5086         err = sel_netnode_sid(addrp, family, &node_sid);
5087         if (err)
5088                 return err;
5089         return avc_has_perm(peer_sid, node_sid,
5090                             SECCLASS_NODE, NODE__RECVFROM, ad);
5091 }
5092
5093 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5094                                        u16 family)
5095 {
5096         int err = 0;
5097         struct sk_security_struct *sksec = selinux_sock(sk);
5098         u32 sk_sid = sksec->sid;
5099         struct common_audit_data ad;
5100         struct lsm_network_audit net;
5101         char *addrp;
5102
5103         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5104         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5105         if (err)
5106                 return err;
5107
5108         if (selinux_secmark_enabled()) {
5109                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5110                                    PACKET__RECV, &ad);
5111                 if (err)
5112                         return err;
5113         }
5114
5115         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5116         if (err)
5117                 return err;
5118         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5119
5120         return err;
5121 }
5122
5123 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5124 {
5125         int err, peerlbl_active, secmark_active;
5126         struct sk_security_struct *sksec = selinux_sock(sk);
5127         u16 family = sk->sk_family;
5128         u32 sk_sid = sksec->sid;
5129         struct common_audit_data ad;
5130         struct lsm_network_audit net;
5131         char *addrp;
5132
5133         if (family != PF_INET && family != PF_INET6)
5134                 return 0;
5135
5136         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5137         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5138                 family = PF_INET;
5139
5140         /* If any sort of compatibility mode is enabled then handoff processing
5141          * to the selinux_sock_rcv_skb_compat() function to deal with the
5142          * special handling.  We do this in an attempt to keep this function
5143          * as fast and as clean as possible. */
5144         if (!selinux_policycap_netpeer())
5145                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5146
5147         secmark_active = selinux_secmark_enabled();
5148         peerlbl_active = selinux_peerlbl_enabled();
5149         if (!secmark_active && !peerlbl_active)
5150                 return 0;
5151
5152         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5153         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5154         if (err)
5155                 return err;
5156
5157         if (peerlbl_active) {
5158                 u32 peer_sid;
5159
5160                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5161                 if (err)
5162                         return err;
5163                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5164                                                addrp, family, peer_sid, &ad);
5165                 if (err) {
5166                         selinux_netlbl_err(skb, family, err, 0);
5167                         return err;
5168                 }
5169                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5170                                    PEER__RECV, &ad);
5171                 if (err) {
5172                         selinux_netlbl_err(skb, family, err, 0);
5173                         return err;
5174                 }
5175         }
5176
5177         if (secmark_active) {
5178                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5179                                    PACKET__RECV, &ad);
5180                 if (err)
5181                         return err;
5182         }
5183
5184         return err;
5185 }
5186
5187 static int selinux_socket_getpeersec_stream(struct socket *sock,
5188                                             sockptr_t optval, sockptr_t optlen,
5189                                             unsigned int len)
5190 {
5191         int err = 0;
5192         char *scontext = NULL;
5193         u32 scontext_len;
5194         struct sk_security_struct *sksec = selinux_sock(sock->sk);
5195         u32 peer_sid = SECSID_NULL;
5196
5197         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5198             sksec->sclass == SECCLASS_TCP_SOCKET ||
5199             sksec->sclass == SECCLASS_SCTP_SOCKET)
5200                 peer_sid = sksec->peer_sid;
5201         if (peer_sid == SECSID_NULL)
5202                 return -ENOPROTOOPT;
5203
5204         err = security_sid_to_context(peer_sid, &scontext,
5205                                       &scontext_len);
5206         if (err)
5207                 return err;
5208         if (scontext_len > len) {
5209                 err = -ERANGE;
5210                 goto out_len;
5211         }
5212
5213         if (copy_to_sockptr(optval, scontext, scontext_len))
5214                 err = -EFAULT;
5215 out_len:
5216         if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5217                 err = -EFAULT;
5218         kfree(scontext);
5219         return err;
5220 }
5221
5222 static int selinux_socket_getpeersec_dgram(struct socket *sock,
5223                                            struct sk_buff *skb, u32 *secid)
5224 {
5225         u32 peer_secid = SECSID_NULL;
5226         u16 family;
5227
5228         if (skb && skb->protocol == htons(ETH_P_IP))
5229                 family = PF_INET;
5230         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5231                 family = PF_INET6;
5232         else if (sock)
5233                 family = sock->sk->sk_family;
5234         else {
5235                 *secid = SECSID_NULL;
5236                 return -EINVAL;
5237         }
5238
5239         if (sock && family == PF_UNIX) {
5240                 struct inode_security_struct *isec;
5241                 isec = inode_security_novalidate(SOCK_INODE(sock));
5242                 peer_secid = isec->sid;
5243         } else if (skb)
5244                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5245
5246         *secid = peer_secid;
5247         if (peer_secid == SECSID_NULL)
5248                 return -ENOPROTOOPT;
5249         return 0;
5250 }
5251
5252 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5253 {
5254         struct sk_security_struct *sksec = selinux_sock(sk);
5255
5256         sksec->peer_sid = SECINITSID_UNLABELED;
5257         sksec->sid = SECINITSID_UNLABELED;
5258         sksec->sclass = SECCLASS_SOCKET;
5259         selinux_netlbl_sk_security_reset(sksec);
5260
5261         return 0;
5262 }
5263
5264 static void selinux_sk_free_security(struct sock *sk)
5265 {
5266         struct sk_security_struct *sksec = selinux_sock(sk);
5267
5268         selinux_netlbl_sk_security_free(sksec);
5269 }
5270
5271 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5272 {
5273         struct sk_security_struct *sksec = selinux_sock(sk);
5274         struct sk_security_struct *newsksec = selinux_sock(newsk);
5275
5276         newsksec->sid = sksec->sid;
5277         newsksec->peer_sid = sksec->peer_sid;
5278         newsksec->sclass = sksec->sclass;
5279
5280         selinux_netlbl_sk_security_reset(newsksec);
5281 }
5282
5283 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5284 {
5285         if (!sk)
5286                 *secid = SECINITSID_ANY_SOCKET;
5287         else {
5288                 const struct sk_security_struct *sksec = selinux_sock(sk);
5289
5290                 *secid = sksec->sid;
5291         }
5292 }
5293
5294 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5295 {
5296         struct inode_security_struct *isec =
5297                 inode_security_novalidate(SOCK_INODE(parent));
5298         struct sk_security_struct *sksec = selinux_sock(sk);
5299
5300         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5301             sk->sk_family == PF_UNIX)
5302                 isec->sid = sksec->sid;
5303         sksec->sclass = isec->sclass;
5304 }
5305
5306 /*
5307  * Determines peer_secid for the asoc and updates socket's peer label
5308  * if it's the first association on the socket.
5309  */
5310 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5311                                           struct sk_buff *skb)
5312 {
5313         struct sock *sk = asoc->base.sk;
5314         u16 family = sk->sk_family;
5315         struct sk_security_struct *sksec = selinux_sock(sk);
5316         struct common_audit_data ad;
5317         struct lsm_network_audit net;
5318         int err;
5319
5320         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5321         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5322                 family = PF_INET;
5323
5324         if (selinux_peerlbl_enabled()) {
5325                 asoc->peer_secid = SECSID_NULL;
5326
5327                 /* This will return peer_sid = SECSID_NULL if there are
5328                  * no peer labels, see security_net_peersid_resolve().
5329                  */
5330                 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5331                 if (err)
5332                         return err;
5333
5334                 if (asoc->peer_secid == SECSID_NULL)
5335                         asoc->peer_secid = SECINITSID_UNLABELED;
5336         } else {
5337                 asoc->peer_secid = SECINITSID_UNLABELED;
5338         }
5339
5340         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5341                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5342
5343                 /* Here as first association on socket. As the peer SID
5344                  * was allowed by peer recv (and the netif/node checks),
5345                  * then it is approved by policy and used as the primary
5346                  * peer SID for getpeercon(3).
5347                  */
5348                 sksec->peer_sid = asoc->peer_secid;
5349         } else if (sksec->peer_sid != asoc->peer_secid) {
5350                 /* Other association peer SIDs are checked to enforce
5351                  * consistency among the peer SIDs.
5352                  */
5353                 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5354                 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5355                                    sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5356                                    &ad);
5357                 if (err)
5358                         return err;
5359         }
5360         return 0;
5361 }
5362
5363 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5364  * happens on an incoming connect(2), sctp_connectx(3) or
5365  * sctp_sendmsg(3) (with no association already present).
5366  */
5367 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5368                                       struct sk_buff *skb)
5369 {
5370         struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5371         u32 conn_sid;
5372         int err;
5373
5374         if (!selinux_policycap_extsockclass())
5375                 return 0;
5376
5377         err = selinux_sctp_process_new_assoc(asoc, skb);
5378         if (err)
5379                 return err;
5380
5381         /* Compute the MLS component for the connection and store
5382          * the information in asoc. This will be used by SCTP TCP type
5383          * sockets and peeled off connections as they cause a new
5384          * socket to be generated. selinux_sctp_sk_clone() will then
5385          * plug this into the new socket.
5386          */
5387         err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5388         if (err)
5389                 return err;
5390
5391         asoc->secid = conn_sid;
5392
5393         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5394         return selinux_netlbl_sctp_assoc_request(asoc, skb);
5395 }
5396
5397 /* Called when SCTP receives a COOKIE ACK chunk as the final
5398  * response to an association request (initited by us).
5399  */
5400 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5401                                           struct sk_buff *skb)
5402 {
5403         struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5404
5405         if (!selinux_policycap_extsockclass())
5406                 return 0;
5407
5408         /* Inherit secid from the parent socket - this will be picked up
5409          * by selinux_sctp_sk_clone() if the association gets peeled off
5410          * into a new socket.
5411          */
5412         asoc->secid = sksec->sid;
5413
5414         return selinux_sctp_process_new_assoc(asoc, skb);
5415 }
5416
5417 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5418  * based on their @optname.
5419  */
5420 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5421                                      struct sockaddr *address,
5422                                      int addrlen)
5423 {
5424         int len, err = 0, walk_size = 0;
5425         void *addr_buf;
5426         struct sockaddr *addr;
5427         struct socket *sock;
5428
5429         if (!selinux_policycap_extsockclass())
5430                 return 0;
5431
5432         /* Process one or more addresses that may be IPv4 or IPv6 */
5433         sock = sk->sk_socket;
5434         addr_buf = address;
5435
5436         while (walk_size < addrlen) {
5437                 if (walk_size + sizeof(sa_family_t) > addrlen)
5438                         return -EINVAL;
5439
5440                 addr = addr_buf;
5441                 switch (addr->sa_family) {
5442                 case AF_UNSPEC:
5443                 case AF_INET:
5444                         len = sizeof(struct sockaddr_in);
5445                         break;
5446                 case AF_INET6:
5447                         len = sizeof(struct sockaddr_in6);
5448                         break;
5449                 default:
5450                         return -EINVAL;
5451                 }
5452
5453                 if (walk_size + len > addrlen)
5454                         return -EINVAL;
5455
5456                 err = -EINVAL;
5457                 switch (optname) {
5458                 /* Bind checks */
5459                 case SCTP_PRIMARY_ADDR:
5460                 case SCTP_SET_PEER_PRIMARY_ADDR:
5461                 case SCTP_SOCKOPT_BINDX_ADD:
5462                         err = selinux_socket_bind(sock, addr, len);
5463                         break;
5464                 /* Connect checks */
5465                 case SCTP_SOCKOPT_CONNECTX:
5466                 case SCTP_PARAM_SET_PRIMARY:
5467                 case SCTP_PARAM_ADD_IP:
5468                 case SCTP_SENDMSG_CONNECT:
5469                         err = selinux_socket_connect_helper(sock, addr, len);
5470                         if (err)
5471                                 return err;
5472
5473                         /* As selinux_sctp_bind_connect() is called by the
5474                          * SCTP protocol layer, the socket is already locked,
5475                          * therefore selinux_netlbl_socket_connect_locked()
5476                          * is called here. The situations handled are:
5477                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5478                          * whenever a new IP address is added or when a new
5479                          * primary address is selected.
5480                          * Note that an SCTP connect(2) call happens before
5481                          * the SCTP protocol layer and is handled via
5482                          * selinux_socket_connect().
5483                          */
5484                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5485                         break;
5486                 }
5487
5488                 if (err)
5489                         return err;
5490
5491                 addr_buf += len;
5492                 walk_size += len;
5493         }
5494
5495         return 0;
5496 }
5497
5498 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5499 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5500                                   struct sock *newsk)
5501 {
5502         struct sk_security_struct *sksec = selinux_sock(sk);
5503         struct sk_security_struct *newsksec = selinux_sock(newsk);
5504
5505         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5506          * the non-sctp clone version.
5507          */
5508         if (!selinux_policycap_extsockclass())
5509                 return selinux_sk_clone_security(sk, newsk);
5510
5511         newsksec->sid = asoc->secid;
5512         newsksec->peer_sid = asoc->peer_secid;
5513         newsksec->sclass = sksec->sclass;
5514         selinux_netlbl_sctp_sk_clone(sk, newsk);
5515 }
5516
5517 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5518 {
5519         struct sk_security_struct *ssksec = selinux_sock(ssk);
5520         struct sk_security_struct *sksec = selinux_sock(sk);
5521
5522         ssksec->sclass = sksec->sclass;
5523         ssksec->sid = sksec->sid;
5524
5525         /* replace the existing subflow label deleting the existing one
5526          * and re-recreating a new label using the updated context
5527          */
5528         selinux_netlbl_sk_security_free(ssksec);
5529         return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5530 }
5531
5532 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5533                                      struct request_sock *req)
5534 {
5535         struct sk_security_struct *sksec = selinux_sock(sk);
5536         int err;
5537         u16 family = req->rsk_ops->family;
5538         u32 connsid;
5539         u32 peersid;
5540
5541         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5542         if (err)
5543                 return err;
5544         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5545         if (err)
5546                 return err;
5547         req->secid = connsid;
5548         req->peer_secid = peersid;
5549
5550         return selinux_netlbl_inet_conn_request(req, family);
5551 }
5552
5553 static void selinux_inet_csk_clone(struct sock *newsk,
5554                                    const struct request_sock *req)
5555 {
5556         struct sk_security_struct *newsksec = selinux_sock(newsk);
5557
5558         newsksec->sid = req->secid;
5559         newsksec->peer_sid = req->peer_secid;
5560         /* NOTE: Ideally, we should also get the isec->sid for the
5561            new socket in sync, but we don't have the isec available yet.
5562            So we will wait until sock_graft to do it, by which
5563            time it will have been created and available. */
5564
5565         /* We don't need to take any sort of lock here as we are the only
5566          * thread with access to newsksec */
5567         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5568 }
5569
5570 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5571 {
5572         u16 family = sk->sk_family;
5573         struct sk_security_struct *sksec = selinux_sock(sk);
5574
5575         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5576         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5577                 family = PF_INET;
5578
5579         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5580 }
5581
5582 static int selinux_secmark_relabel_packet(u32 sid)
5583 {
5584         return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5585                             NULL);
5586 }
5587
5588 static void selinux_secmark_refcount_inc(void)
5589 {
5590         atomic_inc(&selinux_secmark_refcount);
5591 }
5592
5593 static void selinux_secmark_refcount_dec(void)
5594 {
5595         atomic_dec(&selinux_secmark_refcount);
5596 }
5597
5598 static void selinux_req_classify_flow(const struct request_sock *req,
5599                                       struct flowi_common *flic)
5600 {
5601         flic->flowic_secid = req->secid;
5602 }
5603
5604 static int selinux_tun_dev_alloc_security(void *security)
5605 {
5606         struct tun_security_struct *tunsec = selinux_tun_dev(security);
5607
5608         tunsec->sid = current_sid();
5609         return 0;
5610 }
5611
5612 static int selinux_tun_dev_create(void)
5613 {
5614         u32 sid = current_sid();
5615
5616         /* we aren't taking into account the "sockcreate" SID since the socket
5617          * that is being created here is not a socket in the traditional sense,
5618          * instead it is a private sock, accessible only to the kernel, and
5619          * representing a wide range of network traffic spanning multiple
5620          * connections unlike traditional sockets - check the TUN driver to
5621          * get a better understanding of why this socket is special */
5622
5623         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5624                             NULL);
5625 }
5626
5627 static int selinux_tun_dev_attach_queue(void *security)
5628 {
5629         struct tun_security_struct *tunsec = selinux_tun_dev(security);
5630
5631         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5632                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5633 }
5634
5635 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5636 {
5637         struct tun_security_struct *tunsec = selinux_tun_dev(security);
5638         struct sk_security_struct *sksec = selinux_sock(sk);
5639
5640         /* we don't currently perform any NetLabel based labeling here and it
5641          * isn't clear that we would want to do so anyway; while we could apply
5642          * labeling without the support of the TUN user the resulting labeled
5643          * traffic from the other end of the connection would almost certainly
5644          * cause confusion to the TUN user that had no idea network labeling
5645          * protocols were being used */
5646
5647         sksec->sid = tunsec->sid;
5648         sksec->sclass = SECCLASS_TUN_SOCKET;
5649
5650         return 0;
5651 }
5652
5653 static int selinux_tun_dev_open(void *security)
5654 {
5655         struct tun_security_struct *tunsec = selinux_tun_dev(security);
5656         u32 sid = current_sid();
5657         int err;
5658
5659         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5660                            TUN_SOCKET__RELABELFROM, NULL);
5661         if (err)
5662                 return err;
5663         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5664                            TUN_SOCKET__RELABELTO, NULL);
5665         if (err)
5666                 return err;
5667         tunsec->sid = sid;
5668
5669         return 0;
5670 }
5671
5672 #ifdef CONFIG_NETFILTER
5673
5674 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5675                                        const struct nf_hook_state *state)
5676 {
5677         int ifindex;
5678         u16 family;
5679         char *addrp;
5680         u32 peer_sid;
5681         struct common_audit_data ad;
5682         struct lsm_network_audit net;
5683         int secmark_active, peerlbl_active;
5684
5685         if (!selinux_policycap_netpeer())
5686                 return NF_ACCEPT;
5687
5688         secmark_active = selinux_secmark_enabled();
5689         peerlbl_active = selinux_peerlbl_enabled();
5690         if (!secmark_active && !peerlbl_active)
5691                 return NF_ACCEPT;
5692
5693         family = state->pf;
5694         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5695                 return NF_DROP;
5696
5697         ifindex = state->in->ifindex;
5698         ad_net_init_from_iif(&ad, &net, ifindex, family);
5699         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5700                 return NF_DROP;
5701
5702         if (peerlbl_active) {
5703                 int err;
5704
5705                 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5706                                                addrp, family, peer_sid, &ad);
5707                 if (err) {
5708                         selinux_netlbl_err(skb, family, err, 1);
5709                         return NF_DROP;
5710                 }
5711         }
5712
5713         if (secmark_active)
5714                 if (avc_has_perm(peer_sid, skb->secmark,
5715                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5716                         return NF_DROP;
5717
5718         if (netlbl_enabled())
5719                 /* we do this in the FORWARD path and not the POST_ROUTING
5720                  * path because we want to make sure we apply the necessary
5721                  * labeling before IPsec is applied so we can leverage AH
5722                  * protection */
5723                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5724                         return NF_DROP;
5725
5726         return NF_ACCEPT;
5727 }
5728
5729 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5730                                       const struct nf_hook_state *state)
5731 {
5732         struct sock *sk;
5733         u32 sid;
5734
5735         if (!netlbl_enabled())
5736                 return NF_ACCEPT;
5737
5738         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5739          * because we want to make sure we apply the necessary labeling
5740          * before IPsec is applied so we can leverage AH protection */
5741         sk = sk_to_full_sk(skb->sk);
5742         if (sk) {
5743                 struct sk_security_struct *sksec;
5744
5745                 if (sk_listener(sk))
5746                         /* if the socket is the listening state then this
5747                          * packet is a SYN-ACK packet which means it needs to
5748                          * be labeled based on the connection/request_sock and
5749                          * not the parent socket.  unfortunately, we can't
5750                          * lookup the request_sock yet as it isn't queued on
5751                          * the parent socket until after the SYN-ACK is sent.
5752                          * the "solution" is to simply pass the packet as-is
5753                          * as any IP option based labeling should be copied
5754                          * from the initial connection request (in the IP
5755                          * layer).  it is far from ideal, but until we get a
5756                          * security label in the packet itself this is the
5757                          * best we can do. */
5758                         return NF_ACCEPT;
5759
5760                 /* standard practice, label using the parent socket */
5761                 sksec = selinux_sock(sk);
5762                 sid = sksec->sid;
5763         } else
5764                 sid = SECINITSID_KERNEL;
5765         if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5766                 return NF_DROP;
5767
5768         return NF_ACCEPT;
5769 }
5770
5771
5772 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5773                                         const struct nf_hook_state *state)
5774 {
5775         struct sock *sk;
5776         struct sk_security_struct *sksec;
5777         struct common_audit_data ad;
5778         struct lsm_network_audit net;
5779         u8 proto = 0;
5780
5781         sk = skb_to_full_sk(skb);
5782         if (sk == NULL)
5783                 return NF_ACCEPT;
5784         sksec = selinux_sock(sk);
5785
5786         ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5787         if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5788                 return NF_DROP;
5789
5790         if (selinux_secmark_enabled())
5791                 if (avc_has_perm(sksec->sid, skb->secmark,
5792                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5793                         return NF_DROP_ERR(-ECONNREFUSED);
5794
5795         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5796                 return NF_DROP_ERR(-ECONNREFUSED);
5797
5798         return NF_ACCEPT;
5799 }
5800
5801 static unsigned int selinux_ip_postroute(void *priv,
5802                                          struct sk_buff *skb,
5803                                          const struct nf_hook_state *state)
5804 {
5805         u16 family;
5806         u32 secmark_perm;
5807         u32 peer_sid;
5808         int ifindex;
5809         struct sock *sk;
5810         struct common_audit_data ad;
5811         struct lsm_network_audit net;
5812         char *addrp;
5813         int secmark_active, peerlbl_active;
5814
5815         /* If any sort of compatibility mode is enabled then handoff processing
5816          * to the selinux_ip_postroute_compat() function to deal with the
5817          * special handling.  We do this in an attempt to keep this function
5818          * as fast and as clean as possible. */
5819         if (!selinux_policycap_netpeer())
5820                 return selinux_ip_postroute_compat(skb, state);
5821
5822         secmark_active = selinux_secmark_enabled();
5823         peerlbl_active = selinux_peerlbl_enabled();
5824         if (!secmark_active && !peerlbl_active)
5825                 return NF_ACCEPT;
5826
5827         sk = skb_to_full_sk(skb);
5828
5829 #ifdef CONFIG_XFRM
5830         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5831          * packet transformation so allow the packet to pass without any checks
5832          * since we'll have another chance to perform access control checks
5833          * when the packet is on it's final way out.
5834          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5835          *       is NULL, in this case go ahead and apply access control.
5836          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5837          *       TCP listening state we cannot wait until the XFRM processing
5838          *       is done as we will miss out on the SA label if we do;
5839          *       unfortunately, this means more work, but it is only once per
5840          *       connection. */
5841         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5842             !(sk && sk_listener(sk)))
5843                 return NF_ACCEPT;
5844 #endif
5845
5846         family = state->pf;
5847         if (sk == NULL) {
5848                 /* Without an associated socket the packet is either coming
5849                  * from the kernel or it is being forwarded; check the packet
5850                  * to determine which and if the packet is being forwarded
5851                  * query the packet directly to determine the security label. */
5852                 if (skb->skb_iif) {
5853                         secmark_perm = PACKET__FORWARD_OUT;
5854                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5855                                 return NF_DROP;
5856                 } else {
5857                         secmark_perm = PACKET__SEND;
5858                         peer_sid = SECINITSID_KERNEL;
5859                 }
5860         } else if (sk_listener(sk)) {
5861                 /* Locally generated packet but the associated socket is in the
5862                  * listening state which means this is a SYN-ACK packet.  In
5863                  * this particular case the correct security label is assigned
5864                  * to the connection/request_sock but unfortunately we can't
5865                  * query the request_sock as it isn't queued on the parent
5866                  * socket until after the SYN-ACK packet is sent; the only
5867                  * viable choice is to regenerate the label like we do in
5868                  * selinux_inet_conn_request().  See also selinux_ip_output()
5869                  * for similar problems. */
5870                 u32 skb_sid;
5871                 struct sk_security_struct *sksec;
5872
5873                 sksec = selinux_sock(sk);
5874                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5875                         return NF_DROP;
5876                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5877                  * and the packet has been through at least one XFRM
5878                  * transformation then we must be dealing with the "final"
5879                  * form of labeled IPsec packet; since we've already applied
5880                  * all of our access controls on this packet we can safely
5881                  * pass the packet. */
5882                 if (skb_sid == SECSID_NULL) {
5883                         switch (family) {
5884                         case PF_INET:
5885                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5886                                         return NF_ACCEPT;
5887                                 break;
5888                         case PF_INET6:
5889                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5890                                         return NF_ACCEPT;
5891                                 break;
5892                         default:
5893                                 return NF_DROP_ERR(-ECONNREFUSED);
5894                         }
5895                 }
5896                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5897                         return NF_DROP;
5898                 secmark_perm = PACKET__SEND;
5899         } else {
5900                 /* Locally generated packet, fetch the security label from the
5901                  * associated socket. */
5902                 struct sk_security_struct *sksec = selinux_sock(sk);
5903                 peer_sid = sksec->sid;
5904                 secmark_perm = PACKET__SEND;
5905         }
5906
5907         ifindex = state->out->ifindex;
5908         ad_net_init_from_iif(&ad, &net, ifindex, family);
5909         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5910                 return NF_DROP;
5911
5912         if (secmark_active)
5913                 if (avc_has_perm(peer_sid, skb->secmark,
5914                                  SECCLASS_PACKET, secmark_perm, &ad))
5915                         return NF_DROP_ERR(-ECONNREFUSED);
5916
5917         if (peerlbl_active) {
5918                 u32 if_sid;
5919                 u32 node_sid;
5920
5921                 if (sel_netif_sid(state->net, ifindex, &if_sid))
5922                         return NF_DROP;
5923                 if (avc_has_perm(peer_sid, if_sid,
5924                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5925                         return NF_DROP_ERR(-ECONNREFUSED);
5926
5927                 if (sel_netnode_sid(addrp, family, &node_sid))
5928                         return NF_DROP;
5929                 if (avc_has_perm(peer_sid, node_sid,
5930                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5931                         return NF_DROP_ERR(-ECONNREFUSED);
5932         }
5933
5934         return NF_ACCEPT;
5935 }
5936 #endif  /* CONFIG_NETFILTER */
5937
5938 static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type)
5939 {
5940         struct sk_security_struct *sksec = sk->sk_security;
5941         struct common_audit_data ad;
5942         struct lsm_network_audit net;
5943         u8 driver;
5944         u8 xperm;
5945
5946         if (sock_skip_has_perm(sksec->sid))
5947                 return 0;
5948
5949         ad_net_init_from_sk(&ad, &net, sk);
5950
5951         driver = nlmsg_type >> 8;
5952         xperm = nlmsg_type & 0xff;
5953
5954         return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass,
5955                         perms, driver, xperm, &ad);
5956 }
5957
5958 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5959 {
5960         int rc = 0;
5961         unsigned int msg_len;
5962         unsigned int data_len = skb->len;
5963         unsigned char *data = skb->data;
5964         struct nlmsghdr *nlh;
5965         struct sk_security_struct *sksec = selinux_sock(sk);
5966         u16 sclass = sksec->sclass;
5967         u32 perm;
5968
5969         while (data_len >= nlmsg_total_size(0)) {
5970                 nlh = (struct nlmsghdr *)data;
5971
5972                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5973                  *       users which means we can't reject skb's with bogus
5974                  *       length fields; our solution is to follow what
5975                  *       netlink_rcv_skb() does and simply skip processing at
5976                  *       messages with length fields that are clearly junk
5977                  */
5978                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5979                         return 0;
5980
5981                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5982                 if (rc == 0) {
5983                         if (selinux_policycap_netlink_xperm()) {
5984                                 rc = nlmsg_sock_has_extended_perms(
5985                                         sk, perm, nlh->nlmsg_type);
5986                         } else {
5987                                 rc = sock_has_perm(sk, perm);
5988                         }
5989                         if (rc)
5990                                 return rc;
5991                 } else if (rc == -EINVAL) {
5992                         /* -EINVAL is a missing msg/perm mapping */
5993                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5994                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5995                                 " pid=%d comm=%s\n",
5996                                 sk->sk_protocol, nlh->nlmsg_type,
5997                                 secclass_map[sclass - 1].name,
5998                                 task_pid_nr(current), current->comm);
5999                         if (enforcing_enabled() &&
6000                             !security_get_allow_unknown())
6001                                 return rc;
6002                         rc = 0;
6003                 } else if (rc == -ENOENT) {
6004                         /* -ENOENT is a missing socket/class mapping, ignore */
6005                         rc = 0;
6006                 } else {
6007                         return rc;
6008                 }
6009
6010                 /* move to the next message after applying netlink padding */
6011                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6012                 if (msg_len >= data_len)
6013                         return 0;
6014                 data_len -= msg_len;
6015                 data += msg_len;
6016         }
6017
6018         return rc;
6019 }
6020
6021 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6022 {
6023         isec->sclass = sclass;
6024         isec->sid = current_sid();
6025 }
6026
6027 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6028                         u32 perms)
6029 {
6030         struct ipc_security_struct *isec;
6031         struct common_audit_data ad;
6032         u32 sid = current_sid();
6033
6034         isec = selinux_ipc(ipc_perms);
6035
6036         ad.type = LSM_AUDIT_DATA_IPC;
6037         ad.u.ipc_id = ipc_perms->key;
6038
6039         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6040 }
6041
6042 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6043 {
6044         struct msg_security_struct *msec;
6045
6046         msec = selinux_msg_msg(msg);
6047         msec->sid = SECINITSID_UNLABELED;
6048
6049         return 0;
6050 }
6051
6052 /* message queue security operations */
6053 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6054 {
6055         struct ipc_security_struct *isec;
6056         struct common_audit_data ad;
6057         u32 sid = current_sid();
6058
6059         isec = selinux_ipc(msq);
6060         ipc_init_security(isec, SECCLASS_MSGQ);
6061
6062         ad.type = LSM_AUDIT_DATA_IPC;
6063         ad.u.ipc_id = msq->key;
6064
6065         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6066                             MSGQ__CREATE, &ad);
6067 }
6068
6069 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6070 {
6071         struct ipc_security_struct *isec;
6072         struct common_audit_data ad;
6073         u32 sid = current_sid();
6074
6075         isec = selinux_ipc(msq);
6076
6077         ad.type = LSM_AUDIT_DATA_IPC;
6078         ad.u.ipc_id = msq->key;
6079
6080         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6081                             MSGQ__ASSOCIATE, &ad);
6082 }
6083
6084 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6085 {
6086         u32 perms;
6087
6088         switch (cmd) {
6089         case IPC_INFO:
6090         case MSG_INFO:
6091                 /* No specific object, just general system-wide information. */
6092                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6093                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6094         case IPC_STAT:
6095         case MSG_STAT:
6096         case MSG_STAT_ANY:
6097                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6098                 break;
6099         case IPC_SET:
6100                 perms = MSGQ__SETATTR;
6101                 break;
6102         case IPC_RMID:
6103                 perms = MSGQ__DESTROY;
6104                 break;
6105         default:
6106                 return 0;
6107         }
6108
6109         return ipc_has_perm(msq, perms);
6110 }
6111
6112 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6113 {
6114         struct ipc_security_struct *isec;
6115         struct msg_security_struct *msec;
6116         struct common_audit_data ad;
6117         u32 sid = current_sid();
6118         int rc;
6119
6120         isec = selinux_ipc(msq);
6121         msec = selinux_msg_msg(msg);
6122
6123         /*
6124          * First time through, need to assign label to the message
6125          */
6126         if (msec->sid == SECINITSID_UNLABELED) {
6127                 /*
6128                  * Compute new sid based on current process and
6129                  * message queue this message will be stored in
6130                  */
6131                 rc = security_transition_sid(sid, isec->sid,
6132                                              SECCLASS_MSG, NULL, &msec->sid);
6133                 if (rc)
6134                         return rc;
6135         }
6136
6137         ad.type = LSM_AUDIT_DATA_IPC;
6138         ad.u.ipc_id = msq->key;
6139
6140         /* Can this process write to the queue? */
6141         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6142                           MSGQ__WRITE, &ad);
6143         if (!rc)
6144                 /* Can this process send the message */
6145                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6146                                   MSG__SEND, &ad);
6147         if (!rc)
6148                 /* Can the message be put in the queue? */
6149                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6150                                   MSGQ__ENQUEUE, &ad);
6151
6152         return rc;
6153 }
6154
6155 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6156                                     struct task_struct *target,
6157                                     long type, int mode)
6158 {
6159         struct ipc_security_struct *isec;
6160         struct msg_security_struct *msec;
6161         struct common_audit_data ad;
6162         u32 sid = task_sid_obj(target);
6163         int rc;
6164
6165         isec = selinux_ipc(msq);
6166         msec = selinux_msg_msg(msg);
6167
6168         ad.type = LSM_AUDIT_DATA_IPC;
6169         ad.u.ipc_id = msq->key;
6170
6171         rc = avc_has_perm(sid, isec->sid,
6172                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6173         if (!rc)
6174                 rc = avc_has_perm(sid, msec->sid,
6175                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6176         return rc;
6177 }
6178
6179 /* Shared Memory security operations */
6180 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6181 {
6182         struct ipc_security_struct *isec;
6183         struct common_audit_data ad;
6184         u32 sid = current_sid();
6185
6186         isec = selinux_ipc(shp);
6187         ipc_init_security(isec, SECCLASS_SHM);
6188
6189         ad.type = LSM_AUDIT_DATA_IPC;
6190         ad.u.ipc_id = shp->key;
6191
6192         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6193                             SHM__CREATE, &ad);
6194 }
6195
6196 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6197 {
6198         struct ipc_security_struct *isec;
6199         struct common_audit_data ad;
6200         u32 sid = current_sid();
6201
6202         isec = selinux_ipc(shp);
6203
6204         ad.type = LSM_AUDIT_DATA_IPC;
6205         ad.u.ipc_id = shp->key;
6206
6207         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6208                             SHM__ASSOCIATE, &ad);
6209 }
6210
6211 /* Note, at this point, shp is locked down */
6212 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6213 {
6214         u32 perms;
6215
6216         switch (cmd) {
6217         case IPC_INFO:
6218         case SHM_INFO:
6219                 /* No specific object, just general system-wide information. */
6220                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6221                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6222         case IPC_STAT:
6223         case SHM_STAT:
6224         case SHM_STAT_ANY:
6225                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6226                 break;
6227         case IPC_SET:
6228                 perms = SHM__SETATTR;
6229                 break;
6230         case SHM_LOCK:
6231         case SHM_UNLOCK:
6232                 perms = SHM__LOCK;
6233                 break;
6234         case IPC_RMID:
6235                 perms = SHM__DESTROY;
6236                 break;
6237         default:
6238                 return 0;
6239         }
6240
6241         return ipc_has_perm(shp, perms);
6242 }
6243
6244 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6245                              char __user *shmaddr, int shmflg)
6246 {
6247         u32 perms;
6248
6249         if (shmflg & SHM_RDONLY)
6250                 perms = SHM__READ;
6251         else
6252                 perms = SHM__READ | SHM__WRITE;
6253
6254         return ipc_has_perm(shp, perms);
6255 }
6256
6257 /* Semaphore security operations */
6258 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6259 {
6260         struct ipc_security_struct *isec;
6261         struct common_audit_data ad;
6262         u32 sid = current_sid();
6263
6264         isec = selinux_ipc(sma);
6265         ipc_init_security(isec, SECCLASS_SEM);
6266
6267         ad.type = LSM_AUDIT_DATA_IPC;
6268         ad.u.ipc_id = sma->key;
6269
6270         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6271                             SEM__CREATE, &ad);
6272 }
6273
6274 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6275 {
6276         struct ipc_security_struct *isec;
6277         struct common_audit_data ad;
6278         u32 sid = current_sid();
6279
6280         isec = selinux_ipc(sma);
6281
6282         ad.type = LSM_AUDIT_DATA_IPC;
6283         ad.u.ipc_id = sma->key;
6284
6285         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6286                             SEM__ASSOCIATE, &ad);
6287 }
6288
6289 /* Note, at this point, sma is locked down */
6290 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6291 {
6292         int err;
6293         u32 perms;
6294
6295         switch (cmd) {
6296         case IPC_INFO:
6297         case SEM_INFO:
6298                 /* No specific object, just general system-wide information. */
6299                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6300                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6301         case GETPID:
6302         case GETNCNT:
6303         case GETZCNT:
6304                 perms = SEM__GETATTR;
6305                 break;
6306         case GETVAL:
6307         case GETALL:
6308                 perms = SEM__READ;
6309                 break;
6310         case SETVAL:
6311         case SETALL:
6312                 perms = SEM__WRITE;
6313                 break;
6314         case IPC_RMID:
6315                 perms = SEM__DESTROY;
6316                 break;
6317         case IPC_SET:
6318                 perms = SEM__SETATTR;
6319                 break;
6320         case IPC_STAT:
6321         case SEM_STAT:
6322         case SEM_STAT_ANY:
6323                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6324                 break;
6325         default:
6326                 return 0;
6327         }
6328
6329         err = ipc_has_perm(sma, perms);
6330         return err;
6331 }
6332
6333 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6334                              struct sembuf *sops, unsigned nsops, int alter)
6335 {
6336         u32 perms;
6337
6338         if (alter)
6339                 perms = SEM__READ | SEM__WRITE;
6340         else
6341                 perms = SEM__READ;
6342
6343         return ipc_has_perm(sma, perms);
6344 }
6345
6346 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6347 {
6348         u32 av = 0;
6349
6350         av = 0;
6351         if (flag & S_IRUGO)
6352                 av |= IPC__UNIX_READ;
6353         if (flag & S_IWUGO)
6354                 av |= IPC__UNIX_WRITE;
6355
6356         if (av == 0)
6357                 return 0;
6358
6359         return ipc_has_perm(ipcp, av);
6360 }
6361
6362 static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp,
6363                                    struct lsm_prop *prop)
6364 {
6365         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6366         prop->selinux.secid = isec->sid;
6367 }
6368
6369 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6370 {
6371         if (inode)
6372                 inode_doinit_with_dentry(inode, dentry);
6373 }
6374
6375 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6376                                char **value)
6377 {
6378         const struct task_security_struct *tsec;
6379         int error;
6380         u32 sid;
6381         u32 len;
6382
6383         rcu_read_lock();
6384         tsec = selinux_cred(__task_cred(p));
6385         if (p != current) {
6386                 error = avc_has_perm(current_sid(), tsec->sid,
6387                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6388                 if (error)
6389                         goto err_unlock;
6390         }
6391         switch (attr) {
6392         case LSM_ATTR_CURRENT:
6393                 sid = tsec->sid;
6394                 break;
6395         case LSM_ATTR_PREV:
6396                 sid = tsec->osid;
6397                 break;
6398         case LSM_ATTR_EXEC:
6399                 sid = tsec->exec_sid;
6400                 break;
6401         case LSM_ATTR_FSCREATE:
6402                 sid = tsec->create_sid;
6403                 break;
6404         case LSM_ATTR_KEYCREATE:
6405                 sid = tsec->keycreate_sid;
6406                 break;
6407         case LSM_ATTR_SOCKCREATE:
6408                 sid = tsec->sockcreate_sid;
6409                 break;
6410         default:
6411                 error = -EOPNOTSUPP;
6412                 goto err_unlock;
6413         }
6414         rcu_read_unlock();
6415
6416         if (sid == SECSID_NULL) {
6417                 *value = NULL;
6418                 return 0;
6419         }
6420
6421         error = security_sid_to_context(sid, value, &len);
6422         if (error)
6423                 return error;
6424         return len;
6425
6426 err_unlock:
6427         rcu_read_unlock();
6428         return error;
6429 }
6430
6431 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6432 {
6433         struct task_security_struct *tsec;
6434         struct cred *new;
6435         u32 mysid = current_sid(), sid = 0, ptsid;
6436         int error;
6437         char *str = value;
6438
6439         /*
6440          * Basic control over ability to set these attributes at all.
6441          */
6442         switch (attr) {
6443         case LSM_ATTR_EXEC:
6444                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6445                                      PROCESS__SETEXEC, NULL);
6446                 break;
6447         case LSM_ATTR_FSCREATE:
6448                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6449                                      PROCESS__SETFSCREATE, NULL);
6450                 break;
6451         case LSM_ATTR_KEYCREATE:
6452                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6453                                      PROCESS__SETKEYCREATE, NULL);
6454                 break;
6455         case LSM_ATTR_SOCKCREATE:
6456                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6457                                      PROCESS__SETSOCKCREATE, NULL);
6458                 break;
6459         case LSM_ATTR_CURRENT:
6460                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6461                                      PROCESS__SETCURRENT, NULL);
6462                 break;
6463         default:
6464                 error = -EOPNOTSUPP;
6465                 break;
6466         }
6467         if (error)
6468                 return error;
6469
6470         /* Obtain a SID for the context, if one was specified. */
6471         if (size && str[0] && str[0] != '\n') {
6472                 if (str[size-1] == '\n') {
6473                         str[size-1] = 0;
6474                         size--;
6475                 }
6476                 error = security_context_to_sid(value, size,
6477                                                 &sid, GFP_KERNEL);
6478                 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6479                         if (!has_cap_mac_admin(true)) {
6480                                 struct audit_buffer *ab;
6481                                 size_t audit_size;
6482
6483                                 /* We strip a nul only if it is at the end,
6484                                  * otherwise the context contains a nul and
6485                                  * we should audit that */
6486                                 if (str[size - 1] == '\0')
6487                                         audit_size = size - 1;
6488                                 else
6489                                         audit_size = size;
6490                                 ab = audit_log_start(audit_context(),
6491                                                      GFP_ATOMIC,
6492                                                      AUDIT_SELINUX_ERR);
6493                                 if (!ab)
6494                                         return error;
6495                                 audit_log_format(ab, "op=fscreate invalid_context=");
6496                                 audit_log_n_untrustedstring(ab, value,
6497                                                             audit_size);
6498                                 audit_log_end(ab);
6499
6500                                 return error;
6501                         }
6502                         error = security_context_to_sid_force(value, size,
6503                                                         &sid);
6504                 }
6505                 if (error)
6506                         return error;
6507         }
6508
6509         new = prepare_creds();
6510         if (!new)
6511                 return -ENOMEM;
6512
6513         /* Permission checking based on the specified context is
6514            performed during the actual operation (execve,
6515            open/mkdir/...), when we know the full context of the
6516            operation.  See selinux_bprm_creds_for_exec for the execve
6517            checks and may_create for the file creation checks. The
6518            operation will then fail if the context is not permitted. */
6519         tsec = selinux_cred(new);
6520         if (attr == LSM_ATTR_EXEC) {
6521                 tsec->exec_sid = sid;
6522         } else if (attr == LSM_ATTR_FSCREATE) {
6523                 tsec->create_sid = sid;
6524         } else if (attr == LSM_ATTR_KEYCREATE) {
6525                 if (sid) {
6526                         error = avc_has_perm(mysid, sid,
6527                                              SECCLASS_KEY, KEY__CREATE, NULL);
6528                         if (error)
6529                                 goto abort_change;
6530                 }
6531                 tsec->keycreate_sid = sid;
6532         } else if (attr == LSM_ATTR_SOCKCREATE) {
6533                 tsec->sockcreate_sid = sid;
6534         } else if (attr == LSM_ATTR_CURRENT) {
6535                 error = -EINVAL;
6536                 if (sid == 0)
6537                         goto abort_change;
6538
6539                 if (!current_is_single_threaded()) {
6540                         error = security_bounded_transition(tsec->sid, sid);
6541                         if (error)
6542                                 goto abort_change;
6543                 }
6544
6545                 /* Check permissions for the transition. */
6546                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6547                                      PROCESS__DYNTRANSITION, NULL);
6548                 if (error)
6549                         goto abort_change;
6550
6551                 /* Check for ptracing, and update the task SID if ok.
6552                    Otherwise, leave SID unchanged and fail. */
6553                 ptsid = ptrace_parent_sid();
6554                 if (ptsid != 0) {
6555                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6556                                              PROCESS__PTRACE, NULL);
6557                         if (error)
6558                                 goto abort_change;
6559                 }
6560
6561                 tsec->sid = sid;
6562         } else {
6563                 error = -EINVAL;
6564                 goto abort_change;
6565         }
6566
6567         commit_creds(new);
6568         return size;
6569
6570 abort_change:
6571         abort_creds(new);
6572         return error;
6573 }
6574
6575 /**
6576  * selinux_getselfattr - Get SELinux current task attributes
6577  * @attr: the requested attribute
6578  * @ctx: buffer to receive the result
6579  * @size: buffer size (input), buffer size used (output)
6580  * @flags: unused
6581  *
6582  * Fill the passed user space @ctx with the details of the requested
6583  * attribute.
6584  *
6585  * Returns the number of attributes on success, an error code otherwise.
6586  * There will only ever be one attribute.
6587  */
6588 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6589                                u32 *size, u32 flags)
6590 {
6591         int rc;
6592         char *val = NULL;
6593         int val_len;
6594
6595         val_len = selinux_lsm_getattr(attr, current, &val);
6596         if (val_len < 0)
6597                 return val_len;
6598         rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6599         kfree(val);
6600         return (!rc ? 1 : rc);
6601 }
6602
6603 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6604                                u32 size, u32 flags)
6605 {
6606         int rc;
6607
6608         rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6609         if (rc > 0)
6610                 return 0;
6611         return rc;
6612 }
6613
6614 static int selinux_getprocattr(struct task_struct *p,
6615                                const char *name, char **value)
6616 {
6617         unsigned int attr = lsm_name_to_attr(name);
6618         int rc;
6619
6620         if (attr) {
6621                 rc = selinux_lsm_getattr(attr, p, value);
6622                 if (rc != -EOPNOTSUPP)
6623                         return rc;
6624         }
6625
6626         return -EINVAL;
6627 }
6628
6629 static int selinux_setprocattr(const char *name, void *value, size_t size)
6630 {
6631         int attr = lsm_name_to_attr(name);
6632
6633         if (attr)
6634                 return selinux_lsm_setattr(attr, value, size);
6635         return -EINVAL;
6636 }
6637
6638 static int selinux_ismaclabel(const char *name)
6639 {
6640         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6641 }
6642
6643 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6644 {
6645         return security_sid_to_context(secid, secdata, seclen);
6646 }
6647
6648 static int selinux_lsmprop_to_secctx(struct lsm_prop *prop, char **secdata,
6649                                      u32 *seclen)
6650 {
6651         return selinux_secid_to_secctx(prop->selinux.secid, secdata, seclen);
6652 }
6653
6654 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6655 {
6656         return security_context_to_sid(secdata, seclen,
6657                                        secid, GFP_KERNEL);
6658 }
6659
6660 static void selinux_release_secctx(char *secdata, u32 seclen)
6661 {
6662         kfree(secdata);
6663 }
6664
6665 static void selinux_inode_invalidate_secctx(struct inode *inode)
6666 {
6667         struct inode_security_struct *isec = selinux_inode(inode);
6668
6669         spin_lock(&isec->lock);
6670         isec->initialized = LABEL_INVALID;
6671         spin_unlock(&isec->lock);
6672 }
6673
6674 /*
6675  *      called with inode->i_mutex locked
6676  */
6677 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6678 {
6679         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6680                                            ctx, ctxlen, 0);
6681         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6682         return rc == -EOPNOTSUPP ? 0 : rc;
6683 }
6684
6685 /*
6686  *      called with inode->i_mutex locked
6687  */
6688 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6689 {
6690         return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6691                                      ctx, ctxlen, 0, NULL);
6692 }
6693
6694 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6695 {
6696         int len = 0;
6697         len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6698                                         XATTR_SELINUX_SUFFIX, ctx, true);
6699         if (len < 0)
6700                 return len;
6701         *ctxlen = len;
6702         return 0;
6703 }
6704 #ifdef CONFIG_KEYS
6705
6706 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6707                              unsigned long flags)
6708 {
6709         const struct task_security_struct *tsec;
6710         struct key_security_struct *ksec = selinux_key(k);
6711
6712         tsec = selinux_cred(cred);
6713         if (tsec->keycreate_sid)
6714                 ksec->sid = tsec->keycreate_sid;
6715         else
6716                 ksec->sid = tsec->sid;
6717
6718         return 0;
6719 }
6720
6721 static int selinux_key_permission(key_ref_t key_ref,
6722                                   const struct cred *cred,
6723                                   enum key_need_perm need_perm)
6724 {
6725         struct key *key;
6726         struct key_security_struct *ksec;
6727         u32 perm, sid;
6728
6729         switch (need_perm) {
6730         case KEY_NEED_VIEW:
6731                 perm = KEY__VIEW;
6732                 break;
6733         case KEY_NEED_READ:
6734                 perm = KEY__READ;
6735                 break;
6736         case KEY_NEED_WRITE:
6737                 perm = KEY__WRITE;
6738                 break;
6739         case KEY_NEED_SEARCH:
6740                 perm = KEY__SEARCH;
6741                 break;
6742         case KEY_NEED_LINK:
6743                 perm = KEY__LINK;
6744                 break;
6745         case KEY_NEED_SETATTR:
6746                 perm = KEY__SETATTR;
6747                 break;
6748         case KEY_NEED_UNLINK:
6749         case KEY_SYSADMIN_OVERRIDE:
6750         case KEY_AUTHTOKEN_OVERRIDE:
6751         case KEY_DEFER_PERM_CHECK:
6752                 return 0;
6753         default:
6754                 WARN_ON(1);
6755                 return -EPERM;
6756
6757         }
6758
6759         sid = cred_sid(cred);
6760         key = key_ref_to_ptr(key_ref);
6761         ksec = selinux_key(key);
6762
6763         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6764 }
6765
6766 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6767 {
6768         struct key_security_struct *ksec = selinux_key(key);
6769         char *context = NULL;
6770         unsigned len;
6771         int rc;
6772
6773         rc = security_sid_to_context(ksec->sid,
6774                                      &context, &len);
6775         if (!rc)
6776                 rc = len;
6777         *_buffer = context;
6778         return rc;
6779 }
6780
6781 #ifdef CONFIG_KEY_NOTIFICATIONS
6782 static int selinux_watch_key(struct key *key)
6783 {
6784         struct key_security_struct *ksec = selinux_key(key);
6785         u32 sid = current_sid();
6786
6787         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6788 }
6789 #endif
6790 #endif
6791
6792 #ifdef CONFIG_SECURITY_INFINIBAND
6793 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6794 {
6795         struct common_audit_data ad;
6796         int err;
6797         u32 sid = 0;
6798         struct ib_security_struct *sec = ib_sec;
6799         struct lsm_ibpkey_audit ibpkey;
6800
6801         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6802         if (err)
6803                 return err;
6804
6805         ad.type = LSM_AUDIT_DATA_IBPKEY;
6806         ibpkey.subnet_prefix = subnet_prefix;
6807         ibpkey.pkey = pkey_val;
6808         ad.u.ibpkey = &ibpkey;
6809         return avc_has_perm(sec->sid, sid,
6810                             SECCLASS_INFINIBAND_PKEY,
6811                             INFINIBAND_PKEY__ACCESS, &ad);
6812 }
6813
6814 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6815                                             u8 port_num)
6816 {
6817         struct common_audit_data ad;
6818         int err;
6819         u32 sid = 0;
6820         struct ib_security_struct *sec = ib_sec;
6821         struct lsm_ibendport_audit ibendport;
6822
6823         err = security_ib_endport_sid(dev_name, port_num,
6824                                       &sid);
6825
6826         if (err)
6827                 return err;
6828
6829         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6830         ibendport.dev_name = dev_name;
6831         ibendport.port = port_num;
6832         ad.u.ibendport = &ibendport;
6833         return avc_has_perm(sec->sid, sid,
6834                             SECCLASS_INFINIBAND_ENDPORT,
6835                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6836 }
6837
6838 static int selinux_ib_alloc_security(void *ib_sec)
6839 {
6840         struct ib_security_struct *sec = selinux_ib(ib_sec);
6841
6842         sec->sid = current_sid();
6843         return 0;
6844 }
6845 #endif
6846
6847 #ifdef CONFIG_BPF_SYSCALL
6848 static int selinux_bpf(int cmd, union bpf_attr *attr,
6849                                      unsigned int size)
6850 {
6851         u32 sid = current_sid();
6852         int ret;
6853
6854         switch (cmd) {
6855         case BPF_MAP_CREATE:
6856                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6857                                    NULL);
6858                 break;
6859         case BPF_PROG_LOAD:
6860                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6861                                    NULL);
6862                 break;
6863         default:
6864                 ret = 0;
6865                 break;
6866         }
6867
6868         return ret;
6869 }
6870
6871 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6872 {
6873         u32 av = 0;
6874
6875         if (fmode & FMODE_READ)
6876                 av |= BPF__MAP_READ;
6877         if (fmode & FMODE_WRITE)
6878                 av |= BPF__MAP_WRITE;
6879         return av;
6880 }
6881
6882 /* This function will check the file pass through unix socket or binder to see
6883  * if it is a bpf related object. And apply corresponding checks on the bpf
6884  * object based on the type. The bpf maps and programs, not like other files and
6885  * socket, are using a shared anonymous inode inside the kernel as their inode.
6886  * So checking that inode cannot identify if the process have privilege to
6887  * access the bpf object and that's why we have to add this additional check in
6888  * selinux_file_receive and selinux_binder_transfer_files.
6889  */
6890 static int bpf_fd_pass(const struct file *file, u32 sid)
6891 {
6892         struct bpf_security_struct *bpfsec;
6893         struct bpf_prog *prog;
6894         struct bpf_map *map;
6895         int ret;
6896
6897         if (file->f_op == &bpf_map_fops) {
6898                 map = file->private_data;
6899                 bpfsec = map->security;
6900                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6901                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6902                 if (ret)
6903                         return ret;
6904         } else if (file->f_op == &bpf_prog_fops) {
6905                 prog = file->private_data;
6906                 bpfsec = prog->aux->security;
6907                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6908                                    BPF__PROG_RUN, NULL);
6909                 if (ret)
6910                         return ret;
6911         }
6912         return 0;
6913 }
6914
6915 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6916 {
6917         u32 sid = current_sid();
6918         struct bpf_security_struct *bpfsec;
6919
6920         bpfsec = map->security;
6921         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6922                             bpf_map_fmode_to_av(fmode), NULL);
6923 }
6924
6925 static int selinux_bpf_prog(struct bpf_prog *prog)
6926 {
6927         u32 sid = current_sid();
6928         struct bpf_security_struct *bpfsec;
6929
6930         bpfsec = prog->aux->security;
6931         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6932                             BPF__PROG_RUN, NULL);
6933 }
6934
6935 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6936                                   struct bpf_token *token)
6937 {
6938         struct bpf_security_struct *bpfsec;
6939
6940         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6941         if (!bpfsec)
6942                 return -ENOMEM;
6943
6944         bpfsec->sid = current_sid();
6945         map->security = bpfsec;
6946
6947         return 0;
6948 }
6949
6950 static void selinux_bpf_map_free(struct bpf_map *map)
6951 {
6952         struct bpf_security_struct *bpfsec = map->security;
6953
6954         map->security = NULL;
6955         kfree(bpfsec);
6956 }
6957
6958 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6959                                  struct bpf_token *token)
6960 {
6961         struct bpf_security_struct *bpfsec;
6962
6963         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6964         if (!bpfsec)
6965                 return -ENOMEM;
6966
6967         bpfsec->sid = current_sid();
6968         prog->aux->security = bpfsec;
6969
6970         return 0;
6971 }
6972
6973 static void selinux_bpf_prog_free(struct bpf_prog *prog)
6974 {
6975         struct bpf_security_struct *bpfsec = prog->aux->security;
6976
6977         prog->aux->security = NULL;
6978         kfree(bpfsec);
6979 }
6980
6981 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
6982                                     const struct path *path)
6983 {
6984         struct bpf_security_struct *bpfsec;
6985
6986         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6987         if (!bpfsec)
6988                 return -ENOMEM;
6989
6990         bpfsec->sid = current_sid();
6991         token->security = bpfsec;
6992
6993         return 0;
6994 }
6995
6996 static void selinux_bpf_token_free(struct bpf_token *token)
6997 {
6998         struct bpf_security_struct *bpfsec = token->security;
6999
7000         token->security = NULL;
7001         kfree(bpfsec);
7002 }
7003 #endif
7004
7005 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
7006         .lbs_cred = sizeof(struct task_security_struct),
7007         .lbs_file = sizeof(struct file_security_struct),
7008         .lbs_inode = sizeof(struct inode_security_struct),
7009         .lbs_ipc = sizeof(struct ipc_security_struct),
7010         .lbs_key = sizeof(struct key_security_struct),
7011         .lbs_msg_msg = sizeof(struct msg_security_struct),
7012 #ifdef CONFIG_PERF_EVENTS
7013         .lbs_perf_event = sizeof(struct perf_event_security_struct),
7014 #endif
7015         .lbs_sock = sizeof(struct sk_security_struct),
7016         .lbs_superblock = sizeof(struct superblock_security_struct),
7017         .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7018         .lbs_tun_dev = sizeof(struct tun_security_struct),
7019         .lbs_ib = sizeof(struct ib_security_struct),
7020 };
7021
7022 #ifdef CONFIG_PERF_EVENTS
7023 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7024 {
7025         u32 requested, sid = current_sid();
7026
7027         if (type == PERF_SECURITY_OPEN)
7028                 requested = PERF_EVENT__OPEN;
7029         else if (type == PERF_SECURITY_CPU)
7030                 requested = PERF_EVENT__CPU;
7031         else if (type == PERF_SECURITY_KERNEL)
7032                 requested = PERF_EVENT__KERNEL;
7033         else if (type == PERF_SECURITY_TRACEPOINT)
7034                 requested = PERF_EVENT__TRACEPOINT;
7035         else
7036                 return -EINVAL;
7037
7038         return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7039                             requested, NULL);
7040 }
7041
7042 static int selinux_perf_event_alloc(struct perf_event *event)
7043 {
7044         struct perf_event_security_struct *perfsec;
7045
7046         perfsec = selinux_perf_event(event->security);
7047         perfsec->sid = current_sid();
7048
7049         return 0;
7050 }
7051
7052 static int selinux_perf_event_read(struct perf_event *event)
7053 {
7054         struct perf_event_security_struct *perfsec = event->security;
7055         u32 sid = current_sid();
7056
7057         return avc_has_perm(sid, perfsec->sid,
7058                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7059 }
7060
7061 static int selinux_perf_event_write(struct perf_event *event)
7062 {
7063         struct perf_event_security_struct *perfsec = event->security;
7064         u32 sid = current_sid();
7065
7066         return avc_has_perm(sid, perfsec->sid,
7067                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7068 }
7069 #endif
7070
7071 #ifdef CONFIG_IO_URING
7072 /**
7073  * selinux_uring_override_creds - check the requested cred override
7074  * @new: the target creds
7075  *
7076  * Check to see if the current task is allowed to override it's credentials
7077  * to service an io_uring operation.
7078  */
7079 static int selinux_uring_override_creds(const struct cred *new)
7080 {
7081         return avc_has_perm(current_sid(), cred_sid(new),
7082                             SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7083 }
7084
7085 /**
7086  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7087  *
7088  * Check to see if the current task is allowed to create a new io_uring
7089  * kernel polling thread.
7090  */
7091 static int selinux_uring_sqpoll(void)
7092 {
7093         u32 sid = current_sid();
7094
7095         return avc_has_perm(sid, sid,
7096                             SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7097 }
7098
7099 /**
7100  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7101  * @ioucmd: the io_uring command structure
7102  *
7103  * Check to see if the current domain is allowed to execute an
7104  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7105  *
7106  */
7107 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7108 {
7109         struct file *file = ioucmd->file;
7110         struct inode *inode = file_inode(file);
7111         struct inode_security_struct *isec = selinux_inode(inode);
7112         struct common_audit_data ad;
7113
7114         ad.type = LSM_AUDIT_DATA_FILE;
7115         ad.u.file = file;
7116
7117         return avc_has_perm(current_sid(), isec->sid,
7118                             SECCLASS_IO_URING, IO_URING__CMD, &ad);
7119 }
7120 #endif /* CONFIG_IO_URING */
7121
7122 static const struct lsm_id selinux_lsmid = {
7123         .name = "selinux",
7124         .id = LSM_ID_SELINUX,
7125 };
7126
7127 /*
7128  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7129  * 1. any hooks that don't belong to (2.) or (3.) below,
7130  * 2. hooks that both access structures allocated by other hooks, and allocate
7131  *    structures that can be later accessed by other hooks (mostly "cloning"
7132  *    hooks),
7133  * 3. hooks that only allocate structures that can be later accessed by other
7134  *    hooks ("allocating" hooks).
7135  *
7136  * Please follow block comment delimiters in the list to keep this order.
7137  */
7138 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7139         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7140         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7141         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7142         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7143
7144         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7145         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7146         LSM_HOOK_INIT(capget, selinux_capget),
7147         LSM_HOOK_INIT(capset, selinux_capset),
7148         LSM_HOOK_INIT(capable, selinux_capable),
7149         LSM_HOOK_INIT(quotactl, selinux_quotactl),
7150         LSM_HOOK_INIT(quota_on, selinux_quota_on),
7151         LSM_HOOK_INIT(syslog, selinux_syslog),
7152         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7153
7154         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7155
7156         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7157         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7158         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7159
7160         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7161         LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7162         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7163         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7164         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7165         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7166         LSM_HOOK_INIT(sb_mount, selinux_mount),
7167         LSM_HOOK_INIT(sb_umount, selinux_umount),
7168         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7169         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7170
7171         LSM_HOOK_INIT(move_mount, selinux_move_mount),
7172
7173         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7174         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7175
7176         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7177         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7178         LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7179         LSM_HOOK_INIT(inode_create, selinux_inode_create),
7180         LSM_HOOK_INIT(inode_link, selinux_inode_link),
7181         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7182         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7183         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7184         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7185         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7186         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7187         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7188         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7189         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7190         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7191         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7192         LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap),
7193         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7194         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7195         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7196         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7197         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7198         LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7199         LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7200         LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7201         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7202         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7203         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7204         LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop),
7205         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7206         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7207         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7208
7209         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7210
7211         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7212         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7213         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7214         LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7215         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7216         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7217         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7218         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7219         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7220         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7221         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7222         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7223
7224         LSM_HOOK_INIT(file_open, selinux_file_open),
7225
7226         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7227         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7228         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7229         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7230         LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop),
7231         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7232         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7233         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7234         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7235         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7236         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7237         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7238         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7239         LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj),
7240         LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj),
7241         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7242         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7243         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7244         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7245         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7246         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7247         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7248         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7249         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7250         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7251         LSM_HOOK_INIT(userns_create, selinux_userns_create),
7252
7253         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7254         LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop),
7255
7256         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7257         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7258         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7259         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7260
7261         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7262         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7263         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7264
7265         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7266         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7267         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7268
7269         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7270
7271         LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7272         LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7273         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7274         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7275
7276         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7277         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7278         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7279         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7280         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7281         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7282
7283         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7284         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7285
7286         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7287         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7288         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7289         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7290         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7291         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7292         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7293         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7294         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7295         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7296         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7297         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7298         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7299         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7300         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7301         LSM_HOOK_INIT(socket_getpeersec_stream,
7302                         selinux_socket_getpeersec_stream),
7303         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7304         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7305         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7306         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7307         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7308         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7309         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7310         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7311         LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7312         LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7313         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7314         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7315         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7316         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7317         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7318         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7319         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7320         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7321         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7322         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7323         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7324 #ifdef CONFIG_SECURITY_INFINIBAND
7325         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7326         LSM_HOOK_INIT(ib_endport_manage_subnet,
7327                       selinux_ib_endport_manage_subnet),
7328 #endif
7329 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7330         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7331         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7332         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7333         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7334         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7335         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7336                         selinux_xfrm_state_pol_flow_match),
7337         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7338 #endif
7339
7340 #ifdef CONFIG_KEYS
7341         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7342         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7343 #ifdef CONFIG_KEY_NOTIFICATIONS
7344         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7345 #endif
7346 #endif
7347
7348 #ifdef CONFIG_AUDIT
7349         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7350         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7351         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7352 #endif
7353
7354 #ifdef CONFIG_BPF_SYSCALL
7355         LSM_HOOK_INIT(bpf, selinux_bpf),
7356         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7357         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7358         LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7359         LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7360         LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7361 #endif
7362
7363 #ifdef CONFIG_PERF_EVENTS
7364         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7365         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7366         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7367 #endif
7368
7369 #ifdef CONFIG_IO_URING
7370         LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7371         LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7372         LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7373 #endif
7374
7375         /*
7376          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7377          */
7378         LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7379         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7380         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7381         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7382 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7383         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7384 #endif
7385
7386         /*
7387          * PUT "ALLOCATING" HOOKS HERE
7388          */
7389         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7390         LSM_HOOK_INIT(msg_queue_alloc_security,
7391                       selinux_msg_queue_alloc_security),
7392         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7393         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7394         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7395         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7396         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7397         LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx),
7398         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7399         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7400         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7401 #ifdef CONFIG_SECURITY_INFINIBAND
7402         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7403 #endif
7404 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7405         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7406         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7407         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7408                       selinux_xfrm_state_alloc_acquire),
7409 #endif
7410 #ifdef CONFIG_KEYS
7411         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7412 #endif
7413 #ifdef CONFIG_AUDIT
7414         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7415 #endif
7416 #ifdef CONFIG_BPF_SYSCALL
7417         LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7418         LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7419         LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7420 #endif
7421 #ifdef CONFIG_PERF_EVENTS
7422         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7423 #endif
7424 };
7425
7426 static __init int selinux_init(void)
7427 {
7428         pr_info("SELinux:  Initializing.\n");
7429
7430         memset(&selinux_state, 0, sizeof(selinux_state));
7431         enforcing_set(selinux_enforcing_boot);
7432         selinux_avc_init();
7433         mutex_init(&selinux_state.status_lock);
7434         mutex_init(&selinux_state.policy_mutex);
7435
7436         /* Set the security state for the initial task. */
7437         cred_init_security();
7438
7439         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7440         if (!default_noexec)
7441                 pr_notice("SELinux:  virtual memory is executable by default\n");
7442
7443         avc_init();
7444
7445         avtab_cache_init();
7446
7447         ebitmap_cache_init();
7448
7449         hashtab_cache_init();
7450
7451         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7452                            &selinux_lsmid);
7453
7454         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7455                 panic("SELinux: Unable to register AVC netcache callback\n");
7456
7457         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7458                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7459
7460         if (selinux_enforcing_boot)
7461                 pr_debug("SELinux:  Starting in enforcing mode\n");
7462         else
7463                 pr_debug("SELinux:  Starting in permissive mode\n");
7464
7465         fs_validate_description("selinux", selinux_fs_parameters);
7466
7467         return 0;
7468 }
7469
7470 static void delayed_superblock_init(struct super_block *sb, void *unused)
7471 {
7472         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7473 }
7474
7475 void selinux_complete_init(void)
7476 {
7477         pr_debug("SELinux:  Completing initialization.\n");
7478
7479         /* Set up any superblocks initialized prior to the policy load. */
7480         pr_debug("SELinux:  Setting up existing superblocks.\n");
7481         iterate_supers(delayed_superblock_init, NULL);
7482 }
7483
7484 /* SELinux requires early initialization in order to label
7485    all processes and objects when they are created. */
7486 DEFINE_LSM(selinux) = {
7487         .name = "selinux",
7488         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7489         .enabled = &selinux_enabled_boot,
7490         .blobs = &selinux_blob_sizes,
7491         .init = selinux_init,
7492 };
7493
7494 #if defined(CONFIG_NETFILTER)
7495 static const struct nf_hook_ops selinux_nf_ops[] = {
7496         {
7497                 .hook =         selinux_ip_postroute,
7498                 .pf =           NFPROTO_IPV4,
7499                 .hooknum =      NF_INET_POST_ROUTING,
7500                 .priority =     NF_IP_PRI_SELINUX_LAST,
7501         },
7502         {
7503                 .hook =         selinux_ip_forward,
7504                 .pf =           NFPROTO_IPV4,
7505                 .hooknum =      NF_INET_FORWARD,
7506                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7507         },
7508         {
7509                 .hook =         selinux_ip_output,
7510                 .pf =           NFPROTO_IPV4,
7511                 .hooknum =      NF_INET_LOCAL_OUT,
7512                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7513         },
7514 #if IS_ENABLED(CONFIG_IPV6)
7515         {
7516                 .hook =         selinux_ip_postroute,
7517                 .pf =           NFPROTO_IPV6,
7518                 .hooknum =      NF_INET_POST_ROUTING,
7519                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7520         },
7521         {
7522                 .hook =         selinux_ip_forward,
7523                 .pf =           NFPROTO_IPV6,
7524                 .hooknum =      NF_INET_FORWARD,
7525                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7526         },
7527         {
7528                 .hook =         selinux_ip_output,
7529                 .pf =           NFPROTO_IPV6,
7530                 .hooknum =      NF_INET_LOCAL_OUT,
7531                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7532         },
7533 #endif  /* IPV6 */
7534 };
7535
7536 static int __net_init selinux_nf_register(struct net *net)
7537 {
7538         return nf_register_net_hooks(net, selinux_nf_ops,
7539                                      ARRAY_SIZE(selinux_nf_ops));
7540 }
7541
7542 static void __net_exit selinux_nf_unregister(struct net *net)
7543 {
7544         nf_unregister_net_hooks(net, selinux_nf_ops,
7545                                 ARRAY_SIZE(selinux_nf_ops));
7546 }
7547
7548 static struct pernet_operations selinux_net_ops = {
7549         .init = selinux_nf_register,
7550         .exit = selinux_nf_unregister,
7551 };
7552
7553 static int __init selinux_nf_ip_init(void)
7554 {
7555         int err;
7556
7557         if (!selinux_enabled_boot)
7558                 return 0;
7559
7560         pr_debug("SELinux:  Registering netfilter hooks\n");
7561
7562         err = register_pernet_subsys(&selinux_net_ops);
7563         if (err)
7564                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7565
7566         return 0;
7567 }
7568 __initcall(selinux_nf_ip_init);
7569 #endif /* CONFIG_NETFILTER */
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