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         if (selinux_initialized() &&
 286             isec->initialized != LABEL_INITIALIZED) {
 287                 if (!may_sleep)
 288                         return -ECHILD;
 289
 290                 /*
 291                  * Try reloading the inode security label.  This will fail if
 292                  * @opt_dentry is NULL and no dentry for this inode can be
 293                  * found; in that case, continue using the old label.
 294                  */
 295                 inode_doinit_with_dentry(inode, dentry);
 296         }
 297         return 0;
 298 }
 299
 300 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 301 {
 302         return selinux_inode(inode);
 303 }
 304
 305 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 306 {
 307         int error;
 308
 309         error = __inode_security_revalidate(inode, NULL, !rcu);
 310         if (error)
 311                 return ERR_PTR(error);
 312         return selinux_inode(inode);
 313 }
 314
 315 /*
 316  * Get the security label of an inode.
 317  */
 318 static struct inode_security_struct *inode_security(struct inode *inode)
 319 {
 320         __inode_security_revalidate(inode, NULL, true);
 321         return selinux_inode(inode);
 322 }
 323
 324 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 325 {
 326         struct inode *inode = d_backing_inode(dentry);
 327
 328         return selinux_inode(inode);
 329 }
 330
 331 /*
 332  * Get the security label of a dentry's backing inode.
 333  */
 334 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 335 {
 336         struct inode *inode = d_backing_inode(dentry);
 337
 338         __inode_security_revalidate(inode, dentry, true);
 339         return selinux_inode(inode);
 340 }
 341
 342 static void inode_free_security(struct inode *inode)
 343 {
 344         struct inode_security_struct *isec = selinux_inode(inode);
 345         struct superblock_security_struct *sbsec;
 346
 347         if (!isec)
 348                 return;
 349         sbsec = selinux_superblock(inode->i_sb);
 350         /*
 351          * As not all inode security structures are in a list, we check for
 352          * empty list outside of the lock to make sure that we won't waste
 353          * time taking a lock doing nothing.
 354          *
 355          * The list_del_init() function can be safely called more than once.
 356          * It should not be possible for this function to be called with
 357          * concurrent list_add(), but for better safety against future changes
 358          * in the code, we use list_empty_careful() here.
 359          */
 360         if (!list_empty_careful(&isec->list)) {
 361                 spin_lock(&sbsec->isec_lock);
 362                 list_del_init(&isec->list);
 363                 spin_unlock(&sbsec->isec_lock);
 364         }
 365 }
 366
 367 struct selinux_mnt_opts {
 368         u32 fscontext_sid;
 369         u32 context_sid;
 370         u32 rootcontext_sid;
 371         u32 defcontext_sid;
 372 };
 373
 374 static void selinux_free_mnt_opts(void *mnt_opts)
 375 {
 376         kfree(mnt_opts);
 377 }
 378
 379 enum {
 380         Opt_error = -1,
 381         Opt_context = 0,
 382         Opt_defcontext = 1,
 383         Opt_fscontext = 2,
 384         Opt_rootcontext = 3,
 385         Opt_seclabel = 4,
 386 };
 387
 388 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
 389 static const struct {
 390         const char *name;
 391         int len;
 392         int opt;
 393         bool has_arg;
 394 } tokens[] = {
 395         A(context, true),
 396         A(fscontext, true),
 397         A(defcontext, true),
 398         A(rootcontext, true),
 399         A(seclabel, false),
 400 };
 401 #undef A
 402
 403 static int match_opt_prefix(char *s, int l, char **arg)
 404 {
 405         int i;
 406
 407         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 408                 size_t len = tokens[i].len;
 409                 if (len > l || memcmp(s, tokens[i].name, len))
 410                         continue;
 411                 if (tokens[i].has_arg) {
 412                         if (len == l || s[len] != '=')
 413                                 continue;
 414                         *arg = s + len + 1;
 415                 } else if (len != l)
 416                         continue;
 417                 return tokens[i].opt;
 418         }
 419         return Opt_error;
 420 }
 421
 422 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 423
 424 static int may_context_mount_sb_relabel(u32 sid,
 425                         struct superblock_security_struct *sbsec,
 426                         const struct cred *cred)
 427 {
 428         const struct task_security_struct *tsec = selinux_cred(cred);
 429         int rc;
 430
 431         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 432                           FILESYSTEM__RELABELFROM, NULL);
 433         if (rc)
 434                 return rc;
 435
 436         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 437                           FILESYSTEM__RELABELTO, NULL);
 438         return rc;
 439 }
 440
 441 static int may_context_mount_inode_relabel(u32 sid,
 442                         struct superblock_security_struct *sbsec,
 443                         const struct cred *cred)
 444 {
 445         const struct task_security_struct *tsec = selinux_cred(cred);
 446         int rc;
 447         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 448                           FILESYSTEM__RELABELFROM, NULL);
 449         if (rc)
 450                 return rc;
 451
 452         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 453                           FILESYSTEM__ASSOCIATE, NULL);
 454         return rc;
 455 }
 456
 457 static int selinux_is_genfs_special_handling(struct super_block *sb)
 458 {
 459         /* Special handling. Genfs but also in-core setxattr handler */
 460         return  !strcmp(sb->s_type->name, "sysfs") ||
 461                 !strcmp(sb->s_type->name, "pstore") ||
 462                 !strcmp(sb->s_type->name, "debugfs") ||
 463                 !strcmp(sb->s_type->name, "tracefs") ||
 464                 !strcmp(sb->s_type->name, "rootfs") ||
 465                 (selinux_policycap_cgroupseclabel() &&
 466                  (!strcmp(sb->s_type->name, "cgroup") ||
 467                   !strcmp(sb->s_type->name, "cgroup2")));
 468 }
 469
 470 static int selinux_is_sblabel_mnt(struct super_block *sb)
 471 {
 472         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 473
 474         /*
 475          * IMPORTANT: Double-check logic in this function when adding a new
 476          * SECURITY_FS_USE_* definition!
 477          */
 478         BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
 479
 480         switch (sbsec->behavior) {
 481         case SECURITY_FS_USE_XATTR:
 482         case SECURITY_FS_USE_TRANS:
 483         case SECURITY_FS_USE_TASK:
 484         case SECURITY_FS_USE_NATIVE:
 485                 return 1;
 486
 487         case SECURITY_FS_USE_GENFS:
 488                 return selinux_is_genfs_special_handling(sb);
 489
 490         /* Never allow relabeling on context mounts */
 491         case SECURITY_FS_USE_MNTPOINT:
 492         case SECURITY_FS_USE_NONE:
 493         default:
 494                 return 0;
 495         }
 496 }
 497
 498 static int sb_check_xattr_support(struct super_block *sb)
 499 {
 500         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 501         struct dentry *root = sb->s_root;
 502         struct inode *root_inode = d_backing_inode(root);
 503         u32 sid;
 504         int rc;
 505
 506         /*
 507          * Make sure that the xattr handler exists and that no
 508          * error other than -ENODATA is returned by getxattr on
 509          * the root directory.  -ENODATA is ok, as this may be
 510          * the first boot of the SELinux kernel before we have
 511          * assigned xattr values to the filesystem.
 512          */
 513         if (!(root_inode->i_opflags & IOP_XATTR)) {
 514                 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
 515                         sb->s_id, sb->s_type->name);
 516                 goto fallback;
 517         }
 518
 519         rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 520         if (rc < 0 && rc != -ENODATA) {
 521                 if (rc == -EOPNOTSUPP) {
 522                         pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
 523                                 sb->s_id, sb->s_type->name);
 524                         goto fallback;
 525                 } else {
 526                         pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
 527                                 sb->s_id, sb->s_type->name, -rc);
 528                         return rc;
 529                 }
 530         }
 531         return 0;
 532
 533 fallback:
 534         /* No xattr support - try to fallback to genfs if possible. */
 535         rc = security_genfs_sid(sb->s_type->name, "/",
 536                                 SECCLASS_DIR, &sid);
 537         if (rc)
 538                 return -EOPNOTSUPP;
 539
 540         pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
 541                 sb->s_id, sb->s_type->name);
 542         sbsec->behavior = SECURITY_FS_USE_GENFS;
 543         sbsec->sid = sid;
 544         return 0;
 545 }
 546
 547 static int sb_finish_set_opts(struct super_block *sb)
 548 {
 549         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 550         struct dentry *root = sb->s_root;
 551         struct inode *root_inode = d_backing_inode(root);
 552         int rc = 0;
 553
 554         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 555                 rc = sb_check_xattr_support(sb);
 556                 if (rc)
 557                         return rc;
 558         }
 559
 560         sbsec->flags |= SE_SBINITIALIZED;
 561
 562         /*
 563          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 564          * leave the flag untouched because sb_clone_mnt_opts might be handing
 565          * us a superblock that needs the flag to be cleared.
 566          */
 567         if (selinux_is_sblabel_mnt(sb))
 568                 sbsec->flags |= SBLABEL_MNT;
 569         else
 570                 sbsec->flags &= ~SBLABEL_MNT;
 571
 572         /* Initialize the root inode. */
 573         rc = inode_doinit_with_dentry(root_inode, root);
 574
 575         /* Initialize any other inodes associated with the superblock, e.g.
 576            inodes created prior to initial policy load or inodes created
 577            during get_sb by a pseudo filesystem that directly
 578            populates itself. */
 579         spin_lock(&sbsec->isec_lock);
 580         while (!list_empty(&sbsec->isec_head)) {
 581                 struct inode_security_struct *isec =
 582                                 list_first_entry(&sbsec->isec_head,
 583                                            struct inode_security_struct, list);
 584                 struct inode *inode = isec->inode;
 585                 list_del_init(&isec->list);
 586                 spin_unlock(&sbsec->isec_lock);
 587                 inode = igrab(inode);
 588                 if (inode) {
 589                         if (!IS_PRIVATE(inode))
 590                                 inode_doinit_with_dentry(inode, NULL);
 591                         iput(inode);
 592                 }
 593                 spin_lock(&sbsec->isec_lock);
 594         }
 595         spin_unlock(&sbsec->isec_lock);
 596         return rc;
 597 }
 598
 599 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 600                       u32 old_sid, u32 new_sid)
 601 {
 602         char mnt_flags = sbsec->flags & SE_MNTMASK;
 603
 604         /* check if the old mount command had the same options */
 605         if (sbsec->flags & SE_SBINITIALIZED)
 606                 if (!(sbsec->flags & flag) ||
 607                     (old_sid != new_sid))
 608                         return 1;
 609
 610         /* check if we were passed the same options twice,
 611          * aka someone passed context=a,context=b
 612          */
 613         if (!(sbsec->flags & SE_SBINITIALIZED))
 614                 if (mnt_flags & flag)
 615                         return 1;
 616         return 0;
 617 }
 618
 619 /*
 620  * Allow filesystems with binary mount data to explicitly set mount point
 621  * labeling information.
 622  */
 623 static int selinux_set_mnt_opts(struct super_block *sb,
 624                                 void *mnt_opts,
 625                                 unsigned long kern_flags,
 626                                 unsigned long *set_kern_flags)
 627 {
 628         const struct cred *cred = current_cred();
 629         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 630         struct dentry *root = sb->s_root;
 631         struct selinux_mnt_opts *opts = mnt_opts;
 632         struct inode_security_struct *root_isec;
 633         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 634         u32 defcontext_sid = 0;
 635         int rc = 0;
 636
 637         /*
 638          * Specifying internal flags without providing a place to
 639          * place the results is not allowed
 640          */
 641         if (kern_flags && !set_kern_flags)
 642                 return -EINVAL;
 643
 644         mutex_lock(&sbsec->lock);
 645
 646         if (!selinux_initialized()) {
 647                 if (!opts) {
 648                         /* Defer initialization until selinux_complete_init,
 649                            after the initial policy is loaded and the security
 650                            server is ready to handle calls. */
 651                         if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 652                                 sbsec->flags |= SE_SBNATIVE;
 653                                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 654                         }
 655                         goto out;
 656                 }
 657                 rc = -EINVAL;
 658                 pr_warn("SELinux: Unable to set superblock options "
 659                         "before the security server is initialized\n");
 660                 goto out;
 661         }
 662
 663         /*
 664          * Binary mount data FS will come through this function twice.  Once
 665          * from an explicit call and once from the generic calls from the vfs.
 666          * Since the generic VFS calls will not contain any security mount data
 667          * we need to skip the double mount verification.
 668          *
 669          * This does open a hole in which we will not notice if the first
 670          * mount using this sb set explicit options and a second mount using
 671          * this sb does not set any security options.  (The first options
 672          * will be used for both mounts)
 673          */
 674         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 675             && !opts)
 676                 goto out;
 677
 678         root_isec = backing_inode_security_novalidate(root);
 679
 680         /*
 681          * parse the mount options, check if they are valid sids.
 682          * also check if someone is trying to mount the same sb more
 683          * than once with different security options.
 684          */
 685         if (opts) {
 686                 if (opts->fscontext_sid) {
 687                         fscontext_sid = opts->fscontext_sid;
 688                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 689                                         fscontext_sid))
 690                                 goto out_double_mount;
 691                         sbsec->flags |= FSCONTEXT_MNT;
 692                 }
 693                 if (opts->context_sid) {
 694                         context_sid = opts->context_sid;
 695                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 696                                         context_sid))
 697                                 goto out_double_mount;
 698                         sbsec->flags |= CONTEXT_MNT;
 699                 }
 700                 if (opts->rootcontext_sid) {
 701                         rootcontext_sid = opts->rootcontext_sid;
 702                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 703                                         rootcontext_sid))
 704                                 goto out_double_mount;
 705                         sbsec->flags |= ROOTCONTEXT_MNT;
 706                 }
 707                 if (opts->defcontext_sid) {
 708                         defcontext_sid = opts->defcontext_sid;
 709                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 710                                         defcontext_sid))
 711                                 goto out_double_mount;
 712                         sbsec->flags |= DEFCONTEXT_MNT;
 713                 }
 714         }
 715
 716         if (sbsec->flags & SE_SBINITIALIZED) {
 717                 /* previously mounted with options, but not on this attempt? */
 718                 if ((sbsec->flags & SE_MNTMASK) && !opts)
 719                         goto out_double_mount;
 720                 rc = 0;
 721                 goto out;
 722         }
 723
 724         if (strcmp(sb->s_type->name, "proc") == 0)
 725                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 726
 727         if (!strcmp(sb->s_type->name, "debugfs") ||
 728             !strcmp(sb->s_type->name, "tracefs") ||
 729             !strcmp(sb->s_type->name, "binder") ||
 730             !strcmp(sb->s_type->name, "bpf") ||
 731             !strcmp(sb->s_type->name, "pstore") ||
 732             !strcmp(sb->s_type->name, "securityfs"))
 733                 sbsec->flags |= SE_SBGENFS;
 734
 735         if (!strcmp(sb->s_type->name, "sysfs") ||
 736             !strcmp(sb->s_type->name, "cgroup") ||
 737             !strcmp(sb->s_type->name, "cgroup2"))
 738                 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 739
 740         if (!sbsec->behavior) {
 741                 /*
 742                  * Determine the labeling behavior to use for this
 743                  * filesystem type.
 744                  */
 745                 rc = security_fs_use(sb);
 746                 if (rc) {
 747                         pr_warn("%s: security_fs_use(%s) returned %d\n",
 748                                         __func__, sb->s_type->name, rc);
 749                         goto out;
 750                 }
 751         }
 752
 753         /*
 754          * If this is a user namespace mount and the filesystem type is not
 755          * explicitly whitelisted, then no contexts are allowed on the command
 756          * line and security labels must be ignored.
 757          */
 758         if (sb->s_user_ns != &init_user_ns &&
 759             strcmp(sb->s_type->name, "tmpfs") &&
 760             strcmp(sb->s_type->name, "ramfs") &&
 761             strcmp(sb->s_type->name, "devpts") &&
 762             strcmp(sb->s_type->name, "overlay")) {
 763                 if (context_sid || fscontext_sid || rootcontext_sid ||
 764                     defcontext_sid) {
 765                         rc = -EACCES;
 766                         goto out;
 767                 }
 768                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 769                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 770                         rc = security_transition_sid(current_sid(),
 771                                                      current_sid(),
 772                                                      SECCLASS_FILE, NULL,
 773                                                      &sbsec->mntpoint_sid);
 774                         if (rc)
 775                                 goto out;
 776                 }
 777                 goto out_set_opts;
 778         }
 779
 780         /* sets the context of the superblock for the fs being mounted. */
 781         if (fscontext_sid) {
 782                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 783                 if (rc)
 784                         goto out;
 785
 786                 sbsec->sid = fscontext_sid;
 787         }
 788
 789         /*
 790          * Switch to using mount point labeling behavior.
 791          * sets the label used on all file below the mountpoint, and will set
 792          * the superblock context if not already set.
 793          */
 794         if (sbsec->flags & SE_SBNATIVE) {
 795                 /*
 796                  * This means we are initializing a superblock that has been
 797                  * mounted before the SELinux was initialized and the
 798                  * filesystem requested native labeling. We had already
 799                  * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
 800                  * in the original mount attempt, so now we just need to set
 801                  * the SECURITY_FS_USE_NATIVE behavior.
 802                  */
 803                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 804         } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 805                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 806                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 807         }
 808
 809         if (context_sid) {
 810                 if (!fscontext_sid) {
 811                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 812                                                           cred);
 813                         if (rc)
 814                                 goto out;
 815                         sbsec->sid = context_sid;
 816                 } else {
 817                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 818                                                              cred);
 819                         if (rc)
 820                                 goto out;
 821                 }
 822                 if (!rootcontext_sid)
 823                         rootcontext_sid = context_sid;
 824
 825                 sbsec->mntpoint_sid = context_sid;
 826                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 827         }
 828
 829         if (rootcontext_sid) {
 830                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 831                                                      cred);
 832                 if (rc)
 833                         goto out;
 834
 835                 root_isec->sid = rootcontext_sid;
 836                 root_isec->initialized = LABEL_INITIALIZED;
 837         }
 838
 839         if (defcontext_sid) {
 840                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 841                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 842                         rc = -EINVAL;
 843                         pr_warn("SELinux: defcontext option is "
 844                                "invalid for this filesystem type\n");
 845                         goto out;
 846                 }
 847
 848                 if (defcontext_sid != sbsec->def_sid) {
 849                         rc = may_context_mount_inode_relabel(defcontext_sid,
 850                                                              sbsec, cred);
 851                         if (rc)
 852                                 goto out;
 853                 }
 854
 855                 sbsec->def_sid = defcontext_sid;
 856         }
 857
 858 out_set_opts:
 859         rc = sb_finish_set_opts(sb);
 860 out:
 861         mutex_unlock(&sbsec->lock);
 862         return rc;
 863 out_double_mount:
 864         rc = -EINVAL;
 865         pr_warn("SELinux: mount invalid.  Same superblock, different "
 866                "security settings for (dev %s, type %s)\n", sb->s_id,
 867                sb->s_type->name);
 868         goto out;
 869 }
 870
 871 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 872                                     const struct super_block *newsb)
 873 {
 874         struct superblock_security_struct *old = selinux_superblock(oldsb);
 875         struct superblock_security_struct *new = selinux_superblock(newsb);
 876         char oldflags = old->flags & SE_MNTMASK;
 877         char newflags = new->flags & SE_MNTMASK;
 878
 879         if (oldflags != newflags)
 880                 goto mismatch;
 881         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 882                 goto mismatch;
 883         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 884                 goto mismatch;
 885         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 886                 goto mismatch;
 887         if (oldflags & ROOTCONTEXT_MNT) {
 888                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 889                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 890                 if (oldroot->sid != newroot->sid)
 891                         goto mismatch;
 892         }
 893         return 0;
 894 mismatch:
 895         pr_warn("SELinux: mount invalid.  Same superblock, "
 896                             "different security settings for (dev %s, "
 897                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 898         return -EBUSY;
 899 }
 900
 901 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 902                                         struct super_block *newsb,
 903                                         unsigned long kern_flags,
 904                                         unsigned long *set_kern_flags)
 905 {
 906         int rc = 0;
 907         const struct superblock_security_struct *oldsbsec =
 908                                                 selinux_superblock(oldsb);
 909         struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
 910
 911         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 912         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 913         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 914
 915         /*
 916          * Specifying internal flags without providing a place to
 917          * place the results is not allowed.
 918          */
 919         if (kern_flags && !set_kern_flags)
 920                 return -EINVAL;
 921
 922         mutex_lock(&newsbsec->lock);
 923
 924         /*
 925          * if the parent was able to be mounted it clearly had no special lsm
 926          * mount options.  thus we can safely deal with this superblock later
 927          */
 928         if (!selinux_initialized()) {
 929                 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 930                         newsbsec->flags |= SE_SBNATIVE;
 931                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 932                 }
 933                 goto out;
 934         }
 935
 936         /* how can we clone if the old one wasn't set up?? */
 937         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 938
 939         /* if fs is reusing a sb, make sure that the contexts match */
 940         if (newsbsec->flags & SE_SBINITIALIZED) {
 941                 mutex_unlock(&newsbsec->lock);
 942                 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
 943                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 944                 return selinux_cmp_sb_context(oldsb, newsb);
 945         }
 946
 947         newsbsec->flags = oldsbsec->flags;
 948
 949         newsbsec->sid = oldsbsec->sid;
 950         newsbsec->def_sid = oldsbsec->def_sid;
 951         newsbsec->behavior = oldsbsec->behavior;
 952
 953         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
 954                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
 955                 rc = security_fs_use(newsb);
 956                 if (rc)
 957                         goto out;
 958         }
 959
 960         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
 961                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
 962                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 963         }
 964
 965         if (set_context) {
 966                 u32 sid = oldsbsec->mntpoint_sid;
 967
 968                 if (!set_fscontext)
 969                         newsbsec->sid = sid;
 970                 if (!set_rootcontext) {
 971                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 972                         newisec->sid = sid;
 973                 }
 974                 newsbsec->mntpoint_sid = sid;
 975         }
 976         if (set_rootcontext) {
 977                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
 978                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 979
 980                 newisec->sid = oldisec->sid;
 981         }
 982
 983         sb_finish_set_opts(newsb);
 984 out:
 985         mutex_unlock(&newsbsec->lock);
 986         return rc;
 987 }
 988
 989 /*
 990  * NOTE: the caller is responsible for freeing the memory even if on error.
 991  */
 992 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 993 {
 994         struct selinux_mnt_opts *opts = *mnt_opts;
 995         u32 *dst_sid;
 996         int rc;
 997
 998         if (token == Opt_seclabel)
 999                 /* eaten and completely ignored */
1000                 return 0;
1001         if (!s)
1002                 return -EINVAL;
1003
1004         if (!selinux_initialized()) {
1005                 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1006                 return -EINVAL;
1007         }
1008
1009         if (!opts) {
1010                 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1011                 if (!opts)
1012                         return -ENOMEM;
1013                 *mnt_opts = opts;
1014         }
1015
1016         switch (token) {
1017         case Opt_context:
1018                 if (opts->context_sid || opts->defcontext_sid)
1019                         goto err;
1020                 dst_sid = &opts->context_sid;
1021                 break;
1022         case Opt_fscontext:
1023                 if (opts->fscontext_sid)
1024                         goto err;
1025                 dst_sid = &opts->fscontext_sid;
1026                 break;
1027         case Opt_rootcontext:
1028                 if (opts->rootcontext_sid)
1029                         goto err;
1030                 dst_sid = &opts->rootcontext_sid;
1031                 break;
1032         case Opt_defcontext:
1033                 if (opts->context_sid || opts->defcontext_sid)
1034                         goto err;
1035                 dst_sid = &opts->defcontext_sid;
1036                 break;
1037         default:
1038                 WARN_ON(1);
1039                 return -EINVAL;
1040         }
1041         rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1042         if (rc)
1043                 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1044                         s, rc);
1045         return rc;
1046
1047 err:
1048         pr_warn(SEL_MOUNT_FAIL_MSG);
1049         return -EINVAL;
1050 }
1051
1052 static int show_sid(struct seq_file *m, u32 sid)
1053 {
1054         char *context = NULL;
1055         u32 len;
1056         int rc;
1057
1058         rc = security_sid_to_context(sid, &context, &len);
1059         if (!rc) {
1060                 bool has_comma = strchr(context, ',');
1061
1062                 seq_putc(m, '=');
1063                 if (has_comma)
1064                         seq_putc(m, '\"');
1065                 seq_escape(m, context, "\"\n\\");
1066                 if (has_comma)
1067                         seq_putc(m, '\"');
1068         }
1069         kfree(context);
1070         return rc;
1071 }
1072
1073 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1074 {
1075         struct superblock_security_struct *sbsec = selinux_superblock(sb);
1076         int rc;
1077
1078         if (!(sbsec->flags & SE_SBINITIALIZED))
1079                 return 0;
1080
1081         if (!selinux_initialized())
1082                 return 0;
1083
1084         if (sbsec->flags & FSCONTEXT_MNT) {
1085                 seq_putc(m, ',');
1086                 seq_puts(m, FSCONTEXT_STR);
1087                 rc = show_sid(m, sbsec->sid);
1088                 if (rc)
1089                         return rc;
1090         }
1091         if (sbsec->flags & CONTEXT_MNT) {
1092                 seq_putc(m, ',');
1093                 seq_puts(m, CONTEXT_STR);
1094                 rc = show_sid(m, sbsec->mntpoint_sid);
1095                 if (rc)
1096                         return rc;
1097         }
1098         if (sbsec->flags & DEFCONTEXT_MNT) {
1099                 seq_putc(m, ',');
1100                 seq_puts(m, DEFCONTEXT_STR);
1101                 rc = show_sid(m, sbsec->def_sid);
1102                 if (rc)
1103                         return rc;
1104         }
1105         if (sbsec->flags & ROOTCONTEXT_MNT) {
1106                 struct dentry *root = sb->s_root;
1107                 struct inode_security_struct *isec = backing_inode_security(root);
1108                 seq_putc(m, ',');
1109                 seq_puts(m, ROOTCONTEXT_STR);
1110                 rc = show_sid(m, isec->sid);
1111                 if (rc)
1112                         return rc;
1113         }
1114         if (sbsec->flags & SBLABEL_MNT) {
1115                 seq_putc(m, ',');
1116                 seq_puts(m, SECLABEL_STR);
1117         }
1118         return 0;
1119 }
1120
1121 static inline u16 inode_mode_to_security_class(umode_t mode)
1122 {
1123         switch (mode & S_IFMT) {
1124         case S_IFSOCK:
1125                 return SECCLASS_SOCK_FILE;
1126         case S_IFLNK:
1127                 return SECCLASS_LNK_FILE;
1128         case S_IFREG:
1129                 return SECCLASS_FILE;
1130         case S_IFBLK:
1131                 return SECCLASS_BLK_FILE;
1132         case S_IFDIR:
1133                 return SECCLASS_DIR;
1134         case S_IFCHR:
1135                 return SECCLASS_CHR_FILE;
1136         case S_IFIFO:
1137                 return SECCLASS_FIFO_FILE;
1138
1139         }
1140
1141         return SECCLASS_FILE;
1142 }
1143
1144 static inline int default_protocol_stream(int protocol)
1145 {
1146         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1147                 protocol == IPPROTO_MPTCP);
1148 }
1149
1150 static inline int default_protocol_dgram(int protocol)
1151 {
1152         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1153 }
1154
1155 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1156 {
1157         bool extsockclass = selinux_policycap_extsockclass();
1158
1159         switch (family) {
1160         case PF_UNIX:
1161                 switch (type) {
1162                 case SOCK_STREAM:
1163                 case SOCK_SEQPACKET:
1164                         return SECCLASS_UNIX_STREAM_SOCKET;
1165                 case SOCK_DGRAM:
1166                 case SOCK_RAW:
1167                         return SECCLASS_UNIX_DGRAM_SOCKET;
1168                 }
1169                 break;
1170         case PF_INET:
1171         case PF_INET6:
1172                 switch (type) {
1173                 case SOCK_STREAM:
1174                 case SOCK_SEQPACKET:
1175                         if (default_protocol_stream(protocol))
1176                                 return SECCLASS_TCP_SOCKET;
1177                         else if (extsockclass && protocol == IPPROTO_SCTP)
1178                                 return SECCLASS_SCTP_SOCKET;
1179                         else
1180                                 return SECCLASS_RAWIP_SOCKET;
1181                 case SOCK_DGRAM:
1182                         if (default_protocol_dgram(protocol))
1183                                 return SECCLASS_UDP_SOCKET;
1184                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1185                                                   protocol == IPPROTO_ICMPV6))
1186                                 return SECCLASS_ICMP_SOCKET;
1187                         else
1188                                 return SECCLASS_RAWIP_SOCKET;
1189                 case SOCK_DCCP:
1190                         return SECCLASS_DCCP_SOCKET;
1191                 default:
1192                         return SECCLASS_RAWIP_SOCKET;
1193                 }
1194                 break;
1195         case PF_NETLINK:
1196                 switch (protocol) {
1197                 case NETLINK_ROUTE:
1198                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1199                 case NETLINK_SOCK_DIAG:
1200                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1201                 case NETLINK_NFLOG:
1202                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1203                 case NETLINK_XFRM:
1204                         return SECCLASS_NETLINK_XFRM_SOCKET;
1205                 case NETLINK_SELINUX:
1206                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1207                 case NETLINK_ISCSI:
1208                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1209                 case NETLINK_AUDIT:
1210                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1211                 case NETLINK_FIB_LOOKUP:
1212                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1213                 case NETLINK_CONNECTOR:
1214                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1215                 case NETLINK_NETFILTER:
1216                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1217                 case NETLINK_DNRTMSG:
1218                         return SECCLASS_NETLINK_DNRT_SOCKET;
1219                 case NETLINK_KOBJECT_UEVENT:
1220                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1221                 case NETLINK_GENERIC:
1222                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1223                 case NETLINK_SCSITRANSPORT:
1224                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1225                 case NETLINK_RDMA:
1226                         return SECCLASS_NETLINK_RDMA_SOCKET;
1227                 case NETLINK_CRYPTO:
1228                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1229                 default:
1230                         return SECCLASS_NETLINK_SOCKET;
1231                 }
1232         case PF_PACKET:
1233                 return SECCLASS_PACKET_SOCKET;
1234         case PF_KEY:
1235                 return SECCLASS_KEY_SOCKET;
1236         case PF_APPLETALK:
1237                 return SECCLASS_APPLETALK_SOCKET;
1238         }
1239
1240         if (extsockclass) {
1241                 switch (family) {
1242                 case PF_AX25:
1243                         return SECCLASS_AX25_SOCKET;
1244                 case PF_IPX:
1245                         return SECCLASS_IPX_SOCKET;
1246                 case PF_NETROM:
1247                         return SECCLASS_NETROM_SOCKET;
1248                 case PF_ATMPVC:
1249                         return SECCLASS_ATMPVC_SOCKET;
1250                 case PF_X25:
1251                         return SECCLASS_X25_SOCKET;
1252                 case PF_ROSE:
1253                         return SECCLASS_ROSE_SOCKET;
1254                 case PF_DECnet:
1255                         return SECCLASS_DECNET_SOCKET;
1256                 case PF_ATMSVC:
1257                         return SECCLASS_ATMSVC_SOCKET;
1258                 case PF_RDS:
1259                         return SECCLASS_RDS_SOCKET;
1260                 case PF_IRDA:
1261                         return SECCLASS_IRDA_SOCKET;
1262                 case PF_PPPOX:
1263                         return SECCLASS_PPPOX_SOCKET;
1264                 case PF_LLC:
1265                         return SECCLASS_LLC_SOCKET;
1266                 case PF_CAN:
1267                         return SECCLASS_CAN_SOCKET;
1268                 case PF_TIPC:
1269                         return SECCLASS_TIPC_SOCKET;
1270                 case PF_BLUETOOTH:
1271                         return SECCLASS_BLUETOOTH_SOCKET;
1272                 case PF_IUCV:
1273                         return SECCLASS_IUCV_SOCKET;
1274                 case PF_RXRPC:
1275                         return SECCLASS_RXRPC_SOCKET;
1276                 case PF_ISDN:
1277                         return SECCLASS_ISDN_SOCKET;
1278                 case PF_PHONET:
1279                         return SECCLASS_PHONET_SOCKET;
1280                 case PF_IEEE802154:
1281                         return SECCLASS_IEEE802154_SOCKET;
1282                 case PF_CAIF:
1283                         return SECCLASS_CAIF_SOCKET;
1284                 case PF_ALG:
1285                         return SECCLASS_ALG_SOCKET;
1286                 case PF_NFC:
1287                         return SECCLASS_NFC_SOCKET;
1288                 case PF_VSOCK:
1289                         return SECCLASS_VSOCK_SOCKET;
1290                 case PF_KCM:
1291                         return SECCLASS_KCM_SOCKET;
1292                 case PF_QIPCRTR:
1293                         return SECCLASS_QIPCRTR_SOCKET;
1294                 case PF_SMC:
1295                         return SECCLASS_SMC_SOCKET;
1296                 case PF_XDP:
1297                         return SECCLASS_XDP_SOCKET;
1298                 case PF_MCTP:
1299                         return SECCLASS_MCTP_SOCKET;
1300 #if PF_MAX > 46
1301 #error New address family defined, please update this function.
1302 #endif
1303                 }
1304         }
1305
1306         return SECCLASS_SOCKET;
1307 }
1308
1309 static int selinux_genfs_get_sid(struct dentry *dentry,
1310                                  u16 tclass,
1311                                  u16 flags,
1312                                  u32 *sid)
1313 {
1314         int rc;
1315         struct super_block *sb = dentry->d_sb;
1316         char *buffer, *path;
1317
1318         buffer = (char *)__get_free_page(GFP_KERNEL);
1319         if (!buffer)
1320                 return -ENOMEM;
1321
1322         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1323         if (IS_ERR(path))
1324                 rc = PTR_ERR(path);
1325         else {
1326                 if (flags & SE_SBPROC) {
1327                         /* each process gets a /proc/PID/ entry. Strip off the
1328                          * PID part to get a valid selinux labeling.
1329                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1330                         while (path[1] >= '0' && path[1] <= '9') {
1331                                 path[1] = '/';
1332                                 path++;
1333                         }
1334                 }
1335                 rc = security_genfs_sid(sb->s_type->name,
1336                                         path, tclass, sid);
1337                 if (rc == -ENOENT) {
1338                         /* No match in policy, mark as unlabeled. */
1339                         *sid = SECINITSID_UNLABELED;
1340                         rc = 0;
1341                 }
1342         }
1343         free_page((unsigned long)buffer);
1344         return rc;
1345 }
1346
1347 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1348                                   u32 def_sid, u32 *sid)
1349 {
1350 #define INITCONTEXTLEN 255
1351         char *context;
1352         unsigned int len;
1353         int rc;
1354
1355         len = INITCONTEXTLEN;
1356         context = kmalloc(len + 1, GFP_NOFS);
1357         if (!context)
1358                 return -ENOMEM;
1359
1360         context[len] = '\0';
1361         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1362         if (rc == -ERANGE) {
1363                 kfree(context);
1364
1365                 /* Need a larger buffer.  Query for the right size. */
1366                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1367                 if (rc < 0)
1368                         return rc;
1369
1370                 len = rc;
1371                 context = kmalloc(len + 1, GFP_NOFS);
1372                 if (!context)
1373                         return -ENOMEM;
1374
1375                 context[len] = '\0';
1376                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1377                                     context, len);
1378         }
1379         if (rc < 0) {
1380                 kfree(context);
1381                 if (rc != -ENODATA) {
1382                         pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1383                                 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1384                         return rc;
1385                 }
1386                 *sid = def_sid;
1387                 return 0;
1388         }
1389
1390         rc = security_context_to_sid_default(context, rc, sid,
1391                                              def_sid, GFP_NOFS);
1392         if (rc) {
1393                 char *dev = inode->i_sb->s_id;
1394                 unsigned long ino = inode->i_ino;
1395
1396                 if (rc == -EINVAL) {
1397                         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",
1398                                               ino, dev, context);
1399                 } else {
1400                         pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1401                                 __func__, context, -rc, dev, ino);
1402                 }
1403         }
1404         kfree(context);
1405         return 0;
1406 }
1407
1408 /* The inode's security attributes must be initialized before first use. */
1409 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1410 {
1411         struct superblock_security_struct *sbsec = NULL;
1412         struct inode_security_struct *isec = selinux_inode(inode);
1413         u32 task_sid, sid = 0;
1414         u16 sclass;
1415         struct dentry *dentry;
1416         int rc = 0;
1417
1418         if (isec->initialized == LABEL_INITIALIZED)
1419                 return 0;
1420
1421         spin_lock(&isec->lock);
1422         if (isec->initialized == LABEL_INITIALIZED)
1423                 goto out_unlock;
1424
1425         if (isec->sclass == SECCLASS_FILE)
1426                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1427
1428         sbsec = selinux_superblock(inode->i_sb);
1429         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1430                 /* Defer initialization until selinux_complete_init,
1431                    after the initial policy is loaded and the security
1432                    server is ready to handle calls. */
1433                 spin_lock(&sbsec->isec_lock);
1434                 if (list_empty(&isec->list))
1435                         list_add(&isec->list, &sbsec->isec_head);
1436                 spin_unlock(&sbsec->isec_lock);
1437                 goto out_unlock;
1438         }
1439
1440         sclass = isec->sclass;
1441         task_sid = isec->task_sid;
1442         sid = isec->sid;
1443         isec->initialized = LABEL_PENDING;
1444         spin_unlock(&isec->lock);
1445
1446         switch (sbsec->behavior) {
1447         /*
1448          * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1449          * via xattr when called from delayed_superblock_init().
1450          */
1451         case SECURITY_FS_USE_NATIVE:
1452         case SECURITY_FS_USE_XATTR:
1453                 if (!(inode->i_opflags & IOP_XATTR)) {
1454                         sid = sbsec->def_sid;
1455                         break;
1456                 }
1457                 /* Need a dentry, since the xattr API requires one.
1458                    Life would be simpler if we could just pass the inode. */
1459                 if (opt_dentry) {
1460                         /* Called from d_instantiate or d_splice_alias. */
1461                         dentry = dget(opt_dentry);
1462                 } else {
1463                         /*
1464                          * Called from selinux_complete_init, try to find a dentry.
1465                          * Some filesystems really want a connected one, so try
1466                          * that first.  We could split SECURITY_FS_USE_XATTR in
1467                          * two, depending upon that...
1468                          */
1469                         dentry = d_find_alias(inode);
1470                         if (!dentry)
1471                                 dentry = d_find_any_alias(inode);
1472                 }
1473                 if (!dentry) {
1474                         /*
1475                          * this is can be hit on boot when a file is accessed
1476                          * before the policy is loaded.  When we load policy we
1477                          * may find inodes that have no dentry on the
1478                          * sbsec->isec_head list.  No reason to complain as these
1479                          * will get fixed up the next time we go through
1480                          * inode_doinit with a dentry, before these inodes could
1481                          * be used again by userspace.
1482                          */
1483                         goto out_invalid;
1484                 }
1485
1486                 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1487                                             &sid);
1488                 dput(dentry);
1489                 if (rc)
1490                         goto out;
1491                 break;
1492         case SECURITY_FS_USE_TASK:
1493                 sid = task_sid;
1494                 break;
1495         case SECURITY_FS_USE_TRANS:
1496                 /* Default to the fs SID. */
1497                 sid = sbsec->sid;
1498
1499                 /* Try to obtain a transition SID. */
1500                 rc = security_transition_sid(task_sid, sid,
1501                                              sclass, NULL, &sid);
1502                 if (rc)
1503                         goto out;
1504                 break;
1505         case SECURITY_FS_USE_MNTPOINT:
1506                 sid = sbsec->mntpoint_sid;
1507                 break;
1508         default:
1509                 /* Default to the fs superblock SID. */
1510                 sid = sbsec->sid;
1511
1512                 if ((sbsec->flags & SE_SBGENFS) &&
1513                      (!S_ISLNK(inode->i_mode) ||
1514                       selinux_policycap_genfs_seclabel_symlinks())) {
1515                         /* We must have a dentry to determine the label on
1516                          * procfs inodes */
1517                         if (opt_dentry) {
1518                                 /* Called from d_instantiate or
1519                                  * d_splice_alias. */
1520                                 dentry = dget(opt_dentry);
1521                         } else {
1522                                 /* Called from selinux_complete_init, try to
1523                                  * find a dentry.  Some filesystems really want
1524                                  * a connected one, so try that first.
1525                                  */
1526                                 dentry = d_find_alias(inode);
1527                                 if (!dentry)
1528                                         dentry = d_find_any_alias(inode);
1529                         }
1530                         /*
1531                          * This can be hit on boot when a file is accessed
1532                          * before the policy is loaded.  When we load policy we
1533                          * may find inodes that have no dentry on the
1534                          * sbsec->isec_head list.  No reason to complain as
1535                          * these will get fixed up the next time we go through
1536                          * inode_doinit() with a dentry, before these inodes
1537                          * could be used again by userspace.
1538                          */
1539                         if (!dentry)
1540                                 goto out_invalid;
1541                         rc = selinux_genfs_get_sid(dentry, sclass,
1542                                                    sbsec->flags, &sid);
1543                         if (rc) {
1544                                 dput(dentry);
1545                                 goto out;
1546                         }
1547
1548                         if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1549                             (inode->i_opflags & IOP_XATTR)) {
1550                                 rc = inode_doinit_use_xattr(inode, dentry,
1551                                                             sid, &sid);
1552                                 if (rc) {
1553                                         dput(dentry);
1554                                         goto out;
1555                                 }
1556                         }
1557                         dput(dentry);
1558                 }
1559                 break;
1560         }
1561
1562 out:
1563         spin_lock(&isec->lock);
1564         if (isec->initialized == LABEL_PENDING) {
1565                 if (rc) {
1566                         isec->initialized = LABEL_INVALID;
1567                         goto out_unlock;
1568                 }
1569                 isec->initialized = LABEL_INITIALIZED;
1570                 isec->sid = sid;
1571         }
1572
1573 out_unlock:
1574         spin_unlock(&isec->lock);
1575         return rc;
1576
1577 out_invalid:
1578         spin_lock(&isec->lock);
1579         if (isec->initialized == LABEL_PENDING) {
1580                 isec->initialized = LABEL_INVALID;
1581                 isec->sid = sid;
1582         }
1583         spin_unlock(&isec->lock);
1584         return 0;
1585 }
1586
1587 /* Convert a Linux signal to an access vector. */
1588 static inline u32 signal_to_av(int sig)
1589 {
1590         u32 perm = 0;
1591
1592         switch (sig) {
1593         case SIGCHLD:
1594                 /* Commonly granted from child to parent. */
1595                 perm = PROCESS__SIGCHLD;
1596                 break;
1597         case SIGKILL:
1598                 /* Cannot be caught or ignored */
1599                 perm = PROCESS__SIGKILL;
1600                 break;
1601         case SIGSTOP:
1602                 /* Cannot be caught or ignored */
1603                 perm = PROCESS__SIGSTOP;
1604                 break;
1605         default:
1606                 /* All other signals. */
1607                 perm = PROCESS__SIGNAL;
1608                 break;
1609         }
1610
1611         return perm;
1612 }
1613
1614 #if CAP_LAST_CAP > 63
1615 #error Fix SELinux to handle capabilities > 63.
1616 #endif
1617
1618 /* Check whether a task is allowed to use a capability. */
1619 static int cred_has_capability(const struct cred *cred,
1620                                int cap, unsigned int opts, bool initns)
1621 {
1622         struct common_audit_data ad;
1623         struct av_decision avd;
1624         u16 sclass;
1625         u32 sid = cred_sid(cred);
1626         u32 av = CAP_TO_MASK(cap);
1627         int rc;
1628
1629         ad.type = LSM_AUDIT_DATA_CAP;
1630         ad.u.cap = cap;
1631
1632         switch (CAP_TO_INDEX(cap)) {
1633         case 0:
1634                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1635                 break;
1636         case 1:
1637                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1638                 break;
1639         default:
1640                 pr_err("SELinux:  out of range capability %d\n", cap);
1641                 BUG();
1642                 return -EINVAL;
1643         }
1644
1645         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1646         if (!(opts & CAP_OPT_NOAUDIT)) {
1647                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1648                 if (rc2)
1649                         return rc2;
1650         }
1651         return rc;
1652 }
1653
1654 /* Check whether a task has a particular permission to an inode.
1655    The 'adp' parameter is optional and allows other audit
1656    data to be passed (e.g. the dentry). */
1657 static int inode_has_perm(const struct cred *cred,
1658                           struct inode *inode,
1659                           u32 perms,
1660                           struct common_audit_data *adp)
1661 {
1662         struct inode_security_struct *isec;
1663         u32 sid;
1664
1665         if (unlikely(IS_PRIVATE(inode)))
1666                 return 0;
1667
1668         sid = cred_sid(cred);
1669         isec = selinux_inode(inode);
1670
1671         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1672 }
1673
1674 /* Same as inode_has_perm, but pass explicit audit data containing
1675    the dentry to help the auditing code to more easily generate the
1676    pathname if needed. */
1677 static inline int dentry_has_perm(const struct cred *cred,
1678                                   struct dentry *dentry,
1679                                   u32 av)
1680 {
1681         struct inode *inode = d_backing_inode(dentry);
1682         struct common_audit_data ad;
1683
1684         ad.type = LSM_AUDIT_DATA_DENTRY;
1685         ad.u.dentry = dentry;
1686         __inode_security_revalidate(inode, dentry, true);
1687         return inode_has_perm(cred, inode, av, &ad);
1688 }
1689
1690 /* Same as inode_has_perm, but pass explicit audit data containing
1691    the path to help the auditing code to more easily generate the
1692    pathname if needed. */
1693 static inline int path_has_perm(const struct cred *cred,
1694                                 const struct path *path,
1695                                 u32 av)
1696 {
1697         struct inode *inode = d_backing_inode(path->dentry);
1698         struct common_audit_data ad;
1699
1700         ad.type = LSM_AUDIT_DATA_PATH;
1701         ad.u.path = *path;
1702         __inode_security_revalidate(inode, path->dentry, true);
1703         return inode_has_perm(cred, inode, av, &ad);
1704 }
1705
1706 /* Same as path_has_perm, but uses the inode from the file struct. */
1707 static inline int file_path_has_perm(const struct cred *cred,
1708                                      struct file *file,
1709                                      u32 av)
1710 {
1711         struct common_audit_data ad;
1712
1713         ad.type = LSM_AUDIT_DATA_FILE;
1714         ad.u.file = file;
1715         return inode_has_perm(cred, file_inode(file), av, &ad);
1716 }
1717
1718 #ifdef CONFIG_BPF_SYSCALL
1719 static int bpf_fd_pass(const struct file *file, u32 sid);
1720 #endif
1721
1722 /* Check whether a task can use an open file descriptor to
1723    access an inode in a given way.  Check access to the
1724    descriptor itself, and then use dentry_has_perm to
1725    check a particular permission to the file.
1726    Access to the descriptor is implicitly granted if it
1727    has the same SID as the process.  If av is zero, then
1728    access to the file is not checked, e.g. for cases
1729    where only the descriptor is affected like seek. */
1730 static int file_has_perm(const struct cred *cred,
1731                          struct file *file,
1732                          u32 av)
1733 {
1734         struct file_security_struct *fsec = selinux_file(file);
1735         struct inode *inode = file_inode(file);
1736         struct common_audit_data ad;
1737         u32 sid = cred_sid(cred);
1738         int rc;
1739
1740         ad.type = LSM_AUDIT_DATA_FILE;
1741         ad.u.file = file;
1742
1743         if (sid != fsec->sid) {
1744                 rc = avc_has_perm(sid, fsec->sid,
1745                                   SECCLASS_FD,
1746                                   FD__USE,
1747                                   &ad);
1748                 if (rc)
1749                         goto out;
1750         }
1751
1752 #ifdef CONFIG_BPF_SYSCALL
1753         rc = bpf_fd_pass(file, cred_sid(cred));
1754         if (rc)
1755                 return rc;
1756 #endif
1757
1758         /* av is zero if only checking access to the descriptor. */
1759         rc = 0;
1760         if (av)
1761                 rc = inode_has_perm(cred, inode, av, &ad);
1762
1763 out:
1764         return rc;
1765 }
1766
1767 /*
1768  * Determine the label for an inode that might be unioned.
1769  */
1770 static int
1771 selinux_determine_inode_label(const struct task_security_struct *tsec,
1772                                  struct inode *dir,
1773                                  const struct qstr *name, u16 tclass,
1774                                  u32 *_new_isid)
1775 {
1776         const struct superblock_security_struct *sbsec =
1777                                                 selinux_superblock(dir->i_sb);
1778
1779         if ((sbsec->flags & SE_SBINITIALIZED) &&
1780             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1781                 *_new_isid = sbsec->mntpoint_sid;
1782         } else if ((sbsec->flags & SBLABEL_MNT) &&
1783                    tsec->create_sid) {
1784                 *_new_isid = tsec->create_sid;
1785         } else {
1786                 const struct inode_security_struct *dsec = inode_security(dir);
1787                 return security_transition_sid(tsec->sid,
1788                                                dsec->sid, tclass,
1789                                                name, _new_isid);
1790         }
1791
1792         return 0;
1793 }
1794
1795 /* Check whether a task can create a file. */
1796 static int may_create(struct inode *dir,
1797                       struct dentry *dentry,
1798                       u16 tclass)
1799 {
1800         const struct task_security_struct *tsec = selinux_cred(current_cred());
1801         struct inode_security_struct *dsec;
1802         struct superblock_security_struct *sbsec;
1803         u32 sid, newsid;
1804         struct common_audit_data ad;
1805         int rc;
1806
1807         dsec = inode_security(dir);
1808         sbsec = selinux_superblock(dir->i_sb);
1809
1810         sid = tsec->sid;
1811
1812         ad.type = LSM_AUDIT_DATA_DENTRY;
1813         ad.u.dentry = dentry;
1814
1815         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1816                           DIR__ADD_NAME | DIR__SEARCH,
1817                           &ad);
1818         if (rc)
1819                 return rc;
1820
1821         rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1822                                            &newsid);
1823         if (rc)
1824                 return rc;
1825
1826         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1827         if (rc)
1828                 return rc;
1829
1830         return avc_has_perm(newsid, sbsec->sid,
1831                             SECCLASS_FILESYSTEM,
1832                             FILESYSTEM__ASSOCIATE, &ad);
1833 }
1834
1835 #define MAY_LINK        0
1836 #define MAY_UNLINK      1
1837 #define MAY_RMDIR       2
1838
1839 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1840 static int may_link(struct inode *dir,
1841                     struct dentry *dentry,
1842                     int kind)
1843
1844 {
1845         struct inode_security_struct *dsec, *isec;
1846         struct common_audit_data ad;
1847         u32 sid = current_sid();
1848         u32 av;
1849         int rc;
1850
1851         dsec = inode_security(dir);
1852         isec = backing_inode_security(dentry);
1853
1854         ad.type = LSM_AUDIT_DATA_DENTRY;
1855         ad.u.dentry = dentry;
1856
1857         av = DIR__SEARCH;
1858         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1859         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1860         if (rc)
1861                 return rc;
1862
1863         switch (kind) {
1864         case MAY_LINK:
1865                 av = FILE__LINK;
1866                 break;
1867         case MAY_UNLINK:
1868                 av = FILE__UNLINK;
1869                 break;
1870         case MAY_RMDIR:
1871                 av = DIR__RMDIR;
1872                 break;
1873         default:
1874                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
1875                         __func__, kind);
1876                 return 0;
1877         }
1878
1879         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1880         return rc;
1881 }
1882
1883 static inline int may_rename(struct inode *old_dir,
1884                              struct dentry *old_dentry,
1885                              struct inode *new_dir,
1886                              struct dentry *new_dentry)
1887 {
1888         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1889         struct common_audit_data ad;
1890         u32 sid = current_sid();
1891         u32 av;
1892         int old_is_dir, new_is_dir;
1893         int rc;
1894
1895         old_dsec = inode_security(old_dir);
1896         old_isec = backing_inode_security(old_dentry);
1897         old_is_dir = d_is_dir(old_dentry);
1898         new_dsec = inode_security(new_dir);
1899
1900         ad.type = LSM_AUDIT_DATA_DENTRY;
1901
1902         ad.u.dentry = old_dentry;
1903         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1904                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1905         if (rc)
1906                 return rc;
1907         rc = avc_has_perm(sid, old_isec->sid,
1908                           old_isec->sclass, FILE__RENAME, &ad);
1909         if (rc)
1910                 return rc;
1911         if (old_is_dir && new_dir != old_dir) {
1912                 rc = avc_has_perm(sid, old_isec->sid,
1913                                   old_isec->sclass, DIR__REPARENT, &ad);
1914                 if (rc)
1915                         return rc;
1916         }
1917
1918         ad.u.dentry = new_dentry;
1919         av = DIR__ADD_NAME | DIR__SEARCH;
1920         if (d_is_positive(new_dentry))
1921                 av |= DIR__REMOVE_NAME;
1922         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1923         if (rc)
1924                 return rc;
1925         if (d_is_positive(new_dentry)) {
1926                 new_isec = backing_inode_security(new_dentry);
1927                 new_is_dir = d_is_dir(new_dentry);
1928                 rc = avc_has_perm(sid, new_isec->sid,
1929                                   new_isec->sclass,
1930                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1931                 if (rc)
1932                         return rc;
1933         }
1934
1935         return 0;
1936 }
1937
1938 /* Check whether a task can perform a filesystem operation. */
1939 static int superblock_has_perm(const struct cred *cred,
1940                                const struct super_block *sb,
1941                                u32 perms,
1942                                struct common_audit_data *ad)
1943 {
1944         struct superblock_security_struct *sbsec;
1945         u32 sid = cred_sid(cred);
1946
1947         sbsec = selinux_superblock(sb);
1948         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1949 }
1950
1951 /* Convert a Linux mode and permission mask to an access vector. */
1952 static inline u32 file_mask_to_av(int mode, int mask)
1953 {
1954         u32 av = 0;
1955
1956         if (!S_ISDIR(mode)) {
1957                 if (mask & MAY_EXEC)
1958                         av |= FILE__EXECUTE;
1959                 if (mask & MAY_READ)
1960                         av |= FILE__READ;
1961
1962                 if (mask & MAY_APPEND)
1963                         av |= FILE__APPEND;
1964                 else if (mask & MAY_WRITE)
1965                         av |= FILE__WRITE;
1966
1967         } else {
1968                 if (mask & MAY_EXEC)
1969                         av |= DIR__SEARCH;
1970                 if (mask & MAY_WRITE)
1971                         av |= DIR__WRITE;
1972                 if (mask & MAY_READ)
1973                         av |= DIR__READ;
1974         }
1975
1976         return av;
1977 }
1978
1979 /* Convert a Linux file to an access vector. */
1980 static inline u32 file_to_av(const struct file *file)
1981 {
1982         u32 av = 0;
1983
1984         if (file->f_mode & FMODE_READ)
1985                 av |= FILE__READ;
1986         if (file->f_mode & FMODE_WRITE) {
1987                 if (file->f_flags & O_APPEND)
1988                         av |= FILE__APPEND;
1989                 else
1990                         av |= FILE__WRITE;
1991         }
1992         if (!av) {
1993                 /*
1994                  * Special file opened with flags 3 for ioctl-only use.
1995                  */
1996                 av = FILE__IOCTL;
1997         }
1998
1999         return av;
2000 }
2001
2002 /*
2003  * Convert a file to an access vector and include the correct
2004  * open permission.
2005  */
2006 static inline u32 open_file_to_av(struct file *file)
2007 {
2008         u32 av = file_to_av(file);
2009         struct inode *inode = file_inode(file);
2010
2011         if (selinux_policycap_openperm() &&
2012             inode->i_sb->s_magic != SOCKFS_MAGIC)
2013                 av |= FILE__OPEN;
2014
2015         return av;
2016 }
2017
2018 /* Hook functions begin here. */
2019
2020 static int selinux_binder_set_context_mgr(const struct cred *mgr)
2021 {
2022         return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2023                             BINDER__SET_CONTEXT_MGR, NULL);
2024 }
2025
2026 static int selinux_binder_transaction(const struct cred *from,
2027                                       const struct cred *to)
2028 {
2029         u32 mysid = current_sid();
2030         u32 fromsid = cred_sid(from);
2031         u32 tosid = cred_sid(to);
2032         int rc;
2033
2034         if (mysid != fromsid) {
2035                 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2036                                   BINDER__IMPERSONATE, NULL);
2037                 if (rc)
2038                         return rc;
2039         }
2040
2041         return avc_has_perm(fromsid, tosid,
2042                             SECCLASS_BINDER, BINDER__CALL, NULL);
2043 }
2044
2045 static int selinux_binder_transfer_binder(const struct cred *from,
2046                                           const struct cred *to)
2047 {
2048         return avc_has_perm(cred_sid(from), cred_sid(to),
2049                             SECCLASS_BINDER, BINDER__TRANSFER,
2050                             NULL);
2051 }
2052
2053 static int selinux_binder_transfer_file(const struct cred *from,
2054                                         const struct cred *to,
2055                                         const struct file *file)
2056 {
2057         u32 sid = cred_sid(to);
2058         struct file_security_struct *fsec = selinux_file(file);
2059         struct dentry *dentry = file->f_path.dentry;
2060         struct inode_security_struct *isec;
2061         struct common_audit_data ad;
2062         int rc;
2063
2064         ad.type = LSM_AUDIT_DATA_PATH;
2065         ad.u.path = file->f_path;
2066
2067         if (sid != fsec->sid) {
2068                 rc = avc_has_perm(sid, fsec->sid,
2069                                   SECCLASS_FD,
2070                                   FD__USE,
2071                                   &ad);
2072                 if (rc)
2073                         return rc;
2074         }
2075
2076 #ifdef CONFIG_BPF_SYSCALL
2077         rc = bpf_fd_pass(file, sid);
2078         if (rc)
2079                 return rc;
2080 #endif
2081
2082         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2083                 return 0;
2084
2085         isec = backing_inode_security(dentry);
2086         return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2087                             &ad);
2088 }
2089
2090 static int selinux_ptrace_access_check(struct task_struct *child,
2091                                        unsigned int mode)
2092 {
2093         u32 sid = current_sid();
2094         u32 csid = task_sid_obj(child);
2095
2096         if (mode & PTRACE_MODE_READ)
2097                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2098                                 NULL);
2099
2100         return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2101                         NULL);
2102 }
2103
2104 static int selinux_ptrace_traceme(struct task_struct *parent)
2105 {
2106         return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2107                             SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2108 }
2109
2110 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2111                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2112 {
2113         return avc_has_perm(current_sid(), task_sid_obj(target),
2114                         SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2115 }
2116
2117 static int selinux_capset(struct cred *new, const struct cred *old,
2118                           const kernel_cap_t *effective,
2119                           const kernel_cap_t *inheritable,
2120                           const kernel_cap_t *permitted)
2121 {
2122         return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2123                             PROCESS__SETCAP, NULL);
2124 }
2125
2126 /*
2127  * (This comment used to live with the selinux_task_setuid hook,
2128  * which was removed).
2129  *
2130  * Since setuid only affects the current process, and since the SELinux
2131  * controls are not based on the Linux identity attributes, SELinux does not
2132  * need to control this operation.  However, SELinux does control the use of
2133  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2134  */
2135
2136 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2137                            int cap, unsigned int opts)
2138 {
2139         return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2140 }
2141
2142 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2143 {
2144         const struct cred *cred = current_cred();
2145         int rc = 0;
2146
2147         if (!sb)
2148                 return 0;
2149
2150         switch (cmds) {
2151         case Q_SYNC:
2152         case Q_QUOTAON:
2153         case Q_QUOTAOFF:
2154         case Q_SETINFO:
2155         case Q_SETQUOTA:
2156         case Q_XQUOTAOFF:
2157         case Q_XQUOTAON:
2158         case Q_XSETQLIM:
2159                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2160                 break;
2161         case Q_GETFMT:
2162         case Q_GETINFO:
2163         case Q_GETQUOTA:
2164         case Q_XGETQUOTA:
2165         case Q_XGETQSTAT:
2166         case Q_XGETQSTATV:
2167         case Q_XGETNEXTQUOTA:
2168                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2169                 break;
2170         default:
2171                 rc = 0;  /* let the kernel handle invalid cmds */
2172                 break;
2173         }
2174         return rc;
2175 }
2176
2177 static int selinux_quota_on(struct dentry *dentry)
2178 {
2179         const struct cred *cred = current_cred();
2180
2181         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2182 }
2183
2184 static int selinux_syslog(int type)
2185 {
2186         switch (type) {
2187         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2188         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2189                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2190                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2191         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2192         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2193         /* Set level of messages printed to console */
2194         case SYSLOG_ACTION_CONSOLE_LEVEL:
2195                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2196                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2197                                     NULL);
2198         }
2199         /* All other syslog types */
2200         return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2201                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2202 }
2203
2204 /*
2205  * Check that a process has enough memory to allocate a new virtual
2206  * mapping. 0 means there is enough memory for the allocation to
2207  * succeed and -ENOMEM implies there is not.
2208  *
2209  * Do not audit the selinux permission check, as this is applied to all
2210  * processes that allocate mappings.
2211  */
2212 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2213 {
2214         int rc, cap_sys_admin = 0;
2215
2216         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2217                                  CAP_OPT_NOAUDIT, true);
2218         if (rc == 0)
2219                 cap_sys_admin = 1;
2220
2221         return cap_sys_admin;
2222 }
2223
2224 /* binprm security operations */
2225
2226 static u32 ptrace_parent_sid(void)
2227 {
2228         u32 sid = 0;
2229         struct task_struct *tracer;
2230
2231         rcu_read_lock();
2232         tracer = ptrace_parent(current);
2233         if (tracer)
2234                 sid = task_sid_obj(tracer);
2235         rcu_read_unlock();
2236
2237         return sid;
2238 }
2239
2240 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2241                             const struct task_security_struct *old_tsec,
2242                             const struct task_security_struct *new_tsec)
2243 {
2244         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2245         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2246         int rc;
2247         u32 av;
2248
2249         if (!nnp && !nosuid)
2250                 return 0; /* neither NNP nor nosuid */
2251
2252         if (new_tsec->sid == old_tsec->sid)
2253                 return 0; /* No change in credentials */
2254
2255         /*
2256          * If the policy enables the nnp_nosuid_transition policy capability,
2257          * then we permit transitions under NNP or nosuid if the
2258          * policy allows the corresponding permission between
2259          * the old and new contexts.
2260          */
2261         if (selinux_policycap_nnp_nosuid_transition()) {
2262                 av = 0;
2263                 if (nnp)
2264                         av |= PROCESS2__NNP_TRANSITION;
2265                 if (nosuid)
2266                         av |= PROCESS2__NOSUID_TRANSITION;
2267                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2268                                   SECCLASS_PROCESS2, av, NULL);
2269                 if (!rc)
2270                         return 0;
2271         }
2272
2273         /*
2274          * We also permit NNP or nosuid transitions to bounded SIDs,
2275          * i.e. SIDs that are guaranteed to only be allowed a subset
2276          * of the permissions of the current SID.
2277          */
2278         rc = security_bounded_transition(old_tsec->sid,
2279                                          new_tsec->sid);
2280         if (!rc)
2281                 return 0;
2282
2283         /*
2284          * On failure, preserve the errno values for NNP vs nosuid.
2285          * NNP:  Operation not permitted for caller.
2286          * nosuid:  Permission denied to file.
2287          */
2288         if (nnp)
2289                 return -EPERM;
2290         return -EACCES;
2291 }
2292
2293 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2294 {
2295         const struct task_security_struct *old_tsec;
2296         struct task_security_struct *new_tsec;
2297         struct inode_security_struct *isec;
2298         struct common_audit_data ad;
2299         struct inode *inode = file_inode(bprm->file);
2300         int rc;
2301
2302         /* SELinux context only depends on initial program or script and not
2303          * the script interpreter */
2304
2305         old_tsec = selinux_cred(current_cred());
2306         new_tsec = selinux_cred(bprm->cred);
2307         isec = inode_security(inode);
2308
2309         /* Default to the current task SID. */
2310         new_tsec->sid = old_tsec->sid;
2311         new_tsec->osid = old_tsec->sid;
2312
2313         /* Reset fs, key, and sock SIDs on execve. */
2314         new_tsec->create_sid = 0;
2315         new_tsec->keycreate_sid = 0;
2316         new_tsec->sockcreate_sid = 0;
2317
2318         /*
2319          * Before policy is loaded, label any task outside kernel space
2320          * as SECINITSID_INIT, so that any userspace tasks surviving from
2321          * early boot end up with a label different from SECINITSID_KERNEL
2322          * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2323          */
2324         if (!selinux_initialized()) {
2325                 new_tsec->sid = SECINITSID_INIT;
2326                 /* also clear the exec_sid just in case */
2327                 new_tsec->exec_sid = 0;
2328                 return 0;
2329         }
2330
2331         if (old_tsec->exec_sid) {
2332                 new_tsec->sid = old_tsec->exec_sid;
2333                 /* Reset exec SID on execve. */
2334                 new_tsec->exec_sid = 0;
2335
2336                 /* Fail on NNP or nosuid if not an allowed transition. */
2337                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2338                 if (rc)
2339                         return rc;
2340         } else {
2341                 /* Check for a default transition on this program. */
2342                 rc = security_transition_sid(old_tsec->sid,
2343                                              isec->sid, SECCLASS_PROCESS, NULL,
2344                                              &new_tsec->sid);
2345                 if (rc)
2346                         return rc;
2347
2348                 /*
2349                  * Fallback to old SID on NNP or nosuid if not an allowed
2350                  * transition.
2351                  */
2352                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2353                 if (rc)
2354                         new_tsec->sid = old_tsec->sid;
2355         }
2356
2357         ad.type = LSM_AUDIT_DATA_FILE;
2358         ad.u.file = bprm->file;
2359
2360         if (new_tsec->sid == old_tsec->sid) {
2361                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2362                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2363                 if (rc)
2364                         return rc;
2365         } else {
2366                 /* Check permissions for the transition. */
2367                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2368                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2369                 if (rc)
2370                         return rc;
2371
2372                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2373                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2374                 if (rc)
2375                         return rc;
2376
2377                 /* Check for shared state */
2378                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2379                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2380                                           SECCLASS_PROCESS, PROCESS__SHARE,
2381                                           NULL);
2382                         if (rc)
2383                                 return -EPERM;
2384                 }
2385
2386                 /* Make sure that anyone attempting to ptrace over a task that
2387                  * changes its SID has the appropriate permit */
2388                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2389                         u32 ptsid = ptrace_parent_sid();
2390                         if (ptsid != 0) {
2391                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2392                                                   SECCLASS_PROCESS,
2393                                                   PROCESS__PTRACE, NULL);
2394                                 if (rc)
2395                                         return -EPERM;
2396                         }
2397                 }
2398
2399                 /* Clear any possibly unsafe personality bits on exec: */
2400                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2401
2402                 /* Enable secure mode for SIDs transitions unless
2403                    the noatsecure permission is granted between
2404                    the two SIDs, i.e. ahp returns 0. */
2405                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2406                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2407                                   NULL);
2408                 bprm->secureexec |= !!rc;
2409         }
2410
2411         return 0;
2412 }
2413
2414 static int match_file(const void *p, struct file *file, unsigned fd)
2415 {
2416         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2417 }
2418
2419 /* Derived from fs/exec.c:flush_old_files. */
2420 static inline void flush_unauthorized_files(const struct cred *cred,
2421                                             struct files_struct *files)
2422 {
2423         struct file *file, *devnull = NULL;
2424         struct tty_struct *tty;
2425         int drop_tty = 0;
2426         unsigned n;
2427
2428         tty = get_current_tty();
2429         if (tty) {
2430                 spin_lock(&tty->files_lock);
2431                 if (!list_empty(&tty->tty_files)) {
2432                         struct tty_file_private *file_priv;
2433
2434                         /* Revalidate access to controlling tty.
2435                            Use file_path_has_perm on the tty path directly
2436                            rather than using file_has_perm, as this particular
2437                            open file may belong to another process and we are
2438                            only interested in the inode-based check here. */
2439                         file_priv = list_first_entry(&tty->tty_files,
2440                                                 struct tty_file_private, list);
2441                         file = file_priv->file;
2442                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2443                                 drop_tty = 1;
2444                 }
2445                 spin_unlock(&tty->files_lock);
2446                 tty_kref_put(tty);
2447         }
2448         /* Reset controlling tty. */
2449         if (drop_tty)
2450                 no_tty();
2451
2452         /* Revalidate access to inherited open files. */
2453         n = iterate_fd(files, 0, match_file, cred);
2454         if (!n) /* none found? */
2455                 return;
2456
2457         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2458         if (IS_ERR(devnull))
2459                 devnull = NULL;
2460         /* replace all the matching ones with this */
2461         do {
2462                 replace_fd(n - 1, devnull, 0);
2463         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2464         if (devnull)
2465                 fput(devnull);
2466 }
2467
2468 /*
2469  * Prepare a process for imminent new credential changes due to exec
2470  */
2471 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2472 {
2473         struct task_security_struct *new_tsec;
2474         struct rlimit *rlim, *initrlim;
2475         int rc, i;
2476
2477         new_tsec = selinux_cred(bprm->cred);
2478         if (new_tsec->sid == new_tsec->osid)
2479                 return;
2480
2481         /* Close files for which the new task SID is not authorized. */
2482         flush_unauthorized_files(bprm->cred, current->files);
2483
2484         /* Always clear parent death signal on SID transitions. */
2485         current->pdeath_signal = 0;
2486
2487         /* Check whether the new SID can inherit resource limits from the old
2488          * SID.  If not, reset all soft limits to the lower of the current
2489          * task's hard limit and the init task's soft limit.
2490          *
2491          * Note that the setting of hard limits (even to lower them) can be
2492          * controlled by the setrlimit check.  The inclusion of the init task's
2493          * soft limit into the computation is to avoid resetting soft limits
2494          * higher than the default soft limit for cases where the default is
2495          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2496          */
2497         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2498                           PROCESS__RLIMITINH, NULL);
2499         if (rc) {
2500                 /* protect against do_prlimit() */
2501                 task_lock(current);
2502                 for (i = 0; i < RLIM_NLIMITS; i++) {
2503                         rlim = current->signal->rlim + i;
2504                         initrlim = init_task.signal->rlim + i;
2505                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2506                 }
2507                 task_unlock(current);
2508                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2509                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2510         }
2511 }
2512
2513 /*
2514  * Clean up the process immediately after the installation of new credentials
2515  * due to exec
2516  */
2517 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2518 {
2519         const struct task_security_struct *tsec = selinux_cred(current_cred());
2520         u32 osid, sid;
2521         int rc;
2522
2523         osid = tsec->osid;
2524         sid = tsec->sid;
2525
2526         if (sid == osid)
2527                 return;
2528
2529         /* Check whether the new SID can inherit signal state from the old SID.
2530          * If not, clear itimers to avoid subsequent signal generation and
2531          * flush and unblock signals.
2532          *
2533          * This must occur _after_ the task SID has been updated so that any
2534          * kill done after the flush will be checked against the new SID.
2535          */
2536         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2537         if (rc) {
2538                 clear_itimer();
2539
2540                 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2541                 if (!fatal_signal_pending(current)) {
2542                         flush_sigqueue(&current->pending);
2543                         flush_sigqueue(&current->signal->shared_pending);
2544                         flush_signal_handlers(current, 1);
2545                         sigemptyset(&current->blocked);
2546                         recalc_sigpending();
2547                 }
2548                 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2549         }
2550
2551         /* Wake up the parent if it is waiting so that it can recheck
2552          * wait permission to the new task SID. */
2553         read_lock(&tasklist_lock);
2554         __wake_up_parent(current, unrcu_pointer(current->real_parent));
2555         read_unlock(&tasklist_lock);
2556 }
2557
2558 /* superblock security operations */
2559
2560 static int selinux_sb_alloc_security(struct super_block *sb)
2561 {
2562         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2563
2564         mutex_init(&sbsec->lock);
2565         INIT_LIST_HEAD(&sbsec->isec_head);
2566         spin_lock_init(&sbsec->isec_lock);
2567         sbsec->sid = SECINITSID_UNLABELED;
2568         sbsec->def_sid = SECINITSID_FILE;
2569         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2570
2571         return 0;
2572 }
2573
2574 static inline int opt_len(const char *s)
2575 {
2576         bool open_quote = false;
2577         int len;
2578         char c;
2579
2580         for (len = 0; (c = s[len]) != '\0'; len++) {
2581                 if (c == '"')
2582                         open_quote = !open_quote;
2583                 if (c == ',' && !open_quote)
2584                         break;
2585         }
2586         return len;
2587 }
2588
2589 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2590 {
2591         char *from = options;
2592         char *to = options;
2593         bool first = true;
2594         int rc;
2595
2596         while (1) {
2597                 int len = opt_len(from);
2598                 int token;
2599                 char *arg = NULL;
2600
2601                 token = match_opt_prefix(from, len, &arg);
2602
2603                 if (token != Opt_error) {
2604                         char *p, *q;
2605
2606                         /* strip quotes */
2607                         if (arg) {
2608                                 for (p = q = arg; p < from + len; p++) {
2609                                         char c = *p;
2610                                         if (c != '"')
2611                                                 *q++ = c;
2612                                 }
2613                                 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2614                                 if (!arg) {
2615                                         rc = -ENOMEM;
2616                                         goto free_opt;
2617                                 }
2618                         }
2619                         rc = selinux_add_opt(token, arg, mnt_opts);
2620                         kfree(arg);
2621                         arg = NULL;
2622                         if (unlikely(rc)) {
2623                                 goto free_opt;
2624                         }
2625                 } else {
2626                         if (!first) {   // copy with preceding comma
2627                                 from--;
2628                                 len++;
2629                         }
2630                         if (to != from)
2631                                 memmove(to, from, len);
2632                         to += len;
2633                         first = false;
2634                 }
2635                 if (!from[len])
2636                         break;
2637                 from += len + 1;
2638         }
2639         *to = '\0';
2640         return 0;
2641
2642 free_opt:
2643         if (*mnt_opts) {
2644                 selinux_free_mnt_opts(*mnt_opts);
2645                 *mnt_opts = NULL;
2646         }
2647         return rc;
2648 }
2649
2650 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2651 {
2652         struct selinux_mnt_opts *opts = mnt_opts;
2653         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2654
2655         /*
2656          * Superblock not initialized (i.e. no options) - reject if any
2657          * options specified, otherwise accept.
2658          */
2659         if (!(sbsec->flags & SE_SBINITIALIZED))
2660                 return opts ? 1 : 0;
2661
2662         /*
2663          * Superblock initialized and no options specified - reject if
2664          * superblock has any options set, otherwise accept.
2665          */
2666         if (!opts)
2667                 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2668
2669         if (opts->fscontext_sid) {
2670                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2671                                opts->fscontext_sid))
2672                         return 1;
2673         }
2674         if (opts->context_sid) {
2675                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2676                                opts->context_sid))
2677                         return 1;
2678         }
2679         if (opts->rootcontext_sid) {
2680                 struct inode_security_struct *root_isec;
2681
2682                 root_isec = backing_inode_security(sb->s_root);
2683                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2684                                opts->rootcontext_sid))
2685                         return 1;
2686         }
2687         if (opts->defcontext_sid) {
2688                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2689                                opts->defcontext_sid))
2690                         return 1;
2691         }
2692         return 0;
2693 }
2694
2695 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2696 {
2697         struct selinux_mnt_opts *opts = mnt_opts;
2698         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2699
2700         if (!(sbsec->flags & SE_SBINITIALIZED))
2701                 return 0;
2702
2703         if (!opts)
2704                 return 0;
2705
2706         if (opts->fscontext_sid) {
2707                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2708                                opts->fscontext_sid))
2709                         goto out_bad_option;
2710         }
2711         if (opts->context_sid) {
2712                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2713                                opts->context_sid))
2714                         goto out_bad_option;
2715         }
2716         if (opts->rootcontext_sid) {
2717                 struct inode_security_struct *root_isec;
2718                 root_isec = backing_inode_security(sb->s_root);
2719                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2720                                opts->rootcontext_sid))
2721                         goto out_bad_option;
2722         }
2723         if (opts->defcontext_sid) {
2724                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2725                                opts->defcontext_sid))
2726                         goto out_bad_option;
2727         }
2728         return 0;
2729
2730 out_bad_option:
2731         pr_warn("SELinux: unable to change security options "
2732                "during remount (dev %s, type=%s)\n", sb->s_id,
2733                sb->s_type->name);
2734         return -EINVAL;
2735 }
2736
2737 static int selinux_sb_kern_mount(const struct super_block *sb)
2738 {
2739         const struct cred *cred = current_cred();
2740         struct common_audit_data ad;
2741
2742         ad.type = LSM_AUDIT_DATA_DENTRY;
2743         ad.u.dentry = sb->s_root;
2744         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2745 }
2746
2747 static int selinux_sb_statfs(struct dentry *dentry)
2748 {
2749         const struct cred *cred = current_cred();
2750         struct common_audit_data ad;
2751
2752         ad.type = LSM_AUDIT_DATA_DENTRY;
2753         ad.u.dentry = dentry->d_sb->s_root;
2754         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2755 }
2756
2757 static int selinux_mount(const char *dev_name,
2758                          const struct path *path,
2759                          const char *type,
2760                          unsigned long flags,
2761                          void *data)
2762 {
2763         const struct cred *cred = current_cred();
2764
2765         if (flags & MS_REMOUNT)
2766                 return superblock_has_perm(cred, path->dentry->d_sb,
2767                                            FILESYSTEM__REMOUNT, NULL);
2768         else
2769                 return path_has_perm(cred, path, FILE__MOUNTON);
2770 }
2771
2772 static int selinux_move_mount(const struct path *from_path,
2773                               const struct path *to_path)
2774 {
2775         const struct cred *cred = current_cred();
2776
2777         return path_has_perm(cred, to_path, FILE__MOUNTON);
2778 }
2779
2780 static int selinux_umount(struct vfsmount *mnt, int flags)
2781 {
2782         const struct cred *cred = current_cred();
2783
2784         return superblock_has_perm(cred, mnt->mnt_sb,
2785                                    FILESYSTEM__UNMOUNT, NULL);
2786 }
2787
2788 static int selinux_fs_context_submount(struct fs_context *fc,
2789                                    struct super_block *reference)
2790 {
2791         const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2792         struct selinux_mnt_opts *opts;
2793
2794         /*
2795          * Ensure that fc->security remains NULL when no options are set
2796          * as expected by selinux_set_mnt_opts().
2797          */
2798         if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2799                 return 0;
2800
2801         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2802         if (!opts)
2803                 return -ENOMEM;
2804
2805         if (sbsec->flags & FSCONTEXT_MNT)
2806                 opts->fscontext_sid = sbsec->sid;
2807         if (sbsec->flags & CONTEXT_MNT)
2808                 opts->context_sid = sbsec->mntpoint_sid;
2809         if (sbsec->flags & DEFCONTEXT_MNT)
2810                 opts->defcontext_sid = sbsec->def_sid;
2811         fc->security = opts;
2812         return 0;
2813 }
2814
2815 static int selinux_fs_context_dup(struct fs_context *fc,
2816                                   struct fs_context *src_fc)
2817 {
2818         const struct selinux_mnt_opts *src = src_fc->security;
2819
2820         if (!src)
2821                 return 0;
2822
2823         fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2824         return fc->security ? 0 : -ENOMEM;
2825 }
2826
2827 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2828         fsparam_string(CONTEXT_STR,     Opt_context),
2829         fsparam_string(DEFCONTEXT_STR,  Opt_defcontext),
2830         fsparam_string(FSCONTEXT_STR,   Opt_fscontext),
2831         fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2832         fsparam_flag  (SECLABEL_STR,    Opt_seclabel),
2833         {}
2834 };
2835
2836 static int selinux_fs_context_parse_param(struct fs_context *fc,
2837                                           struct fs_parameter *param)
2838 {
2839         struct fs_parse_result result;
2840         int opt;
2841
2842         opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2843         if (opt < 0)
2844                 return opt;
2845
2846         return selinux_add_opt(opt, param->string, &fc->security);
2847 }
2848
2849 /* inode security operations */
2850
2851 static int selinux_inode_alloc_security(struct inode *inode)
2852 {
2853         struct inode_security_struct *isec = selinux_inode(inode);
2854         u32 sid = current_sid();
2855
2856         spin_lock_init(&isec->lock);
2857         INIT_LIST_HEAD(&isec->list);
2858         isec->inode = inode;
2859         isec->sid = SECINITSID_UNLABELED;
2860         isec->sclass = SECCLASS_FILE;
2861         isec->task_sid = sid;
2862         isec->initialized = LABEL_INVALID;
2863
2864         return 0;
2865 }
2866
2867 static void selinux_inode_free_security(struct inode *inode)
2868 {
2869         inode_free_security(inode);
2870 }
2871
2872 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2873                                         const struct qstr *name,
2874                                         const char **xattr_name, void **ctx,
2875                                         u32 *ctxlen)
2876 {
2877         u32 newsid;
2878         int rc;
2879
2880         rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2881                                            d_inode(dentry->d_parent), name,
2882                                            inode_mode_to_security_class(mode),
2883                                            &newsid);
2884         if (rc)
2885                 return rc;
2886
2887         if (xattr_name)
2888                 *xattr_name = XATTR_NAME_SELINUX;
2889
2890         return security_sid_to_context(newsid, (char **)ctx,
2891                                        ctxlen);
2892 }
2893
2894 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2895                                           struct qstr *name,
2896                                           const struct cred *old,
2897                                           struct cred *new)
2898 {
2899         u32 newsid;
2900         int rc;
2901         struct task_security_struct *tsec;
2902
2903         rc = selinux_determine_inode_label(selinux_cred(old),
2904                                            d_inode(dentry->d_parent), name,
2905                                            inode_mode_to_security_class(mode),
2906                                            &newsid);
2907         if (rc)
2908                 return rc;
2909
2910         tsec = selinux_cred(new);
2911         tsec->create_sid = newsid;
2912         return 0;
2913 }
2914
2915 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2916                                        const struct qstr *qstr,
2917                                        struct xattr *xattrs, int *xattr_count)
2918 {
2919         const struct task_security_struct *tsec = selinux_cred(current_cred());
2920         struct superblock_security_struct *sbsec;
2921         struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2922         u32 newsid, clen;
2923         u16 newsclass;
2924         int rc;
2925         char *context;
2926
2927         sbsec = selinux_superblock(dir->i_sb);
2928
2929         newsid = tsec->create_sid;
2930         newsclass = inode_mode_to_security_class(inode->i_mode);
2931         rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid);
2932         if (rc)
2933                 return rc;
2934
2935         /* Possibly defer initialization to selinux_complete_init. */
2936         if (sbsec->flags & SE_SBINITIALIZED) {
2937                 struct inode_security_struct *isec = selinux_inode(inode);
2938                 isec->sclass = newsclass;
2939                 isec->sid = newsid;
2940                 isec->initialized = LABEL_INITIALIZED;
2941         }
2942
2943         if (!selinux_initialized() ||
2944             !(sbsec->flags & SBLABEL_MNT))
2945                 return -EOPNOTSUPP;
2946
2947         if (xattr) {
2948                 rc = security_sid_to_context_force(newsid,
2949                                                    &context, &clen);
2950                 if (rc)
2951                         return rc;
2952                 xattr->value = context;
2953                 xattr->value_len = clen;
2954                 xattr->name = XATTR_SELINUX_SUFFIX;
2955         }
2956
2957         return 0;
2958 }
2959
2960 static int selinux_inode_init_security_anon(struct inode *inode,
2961                                             const struct qstr *name,
2962                                             const struct inode *context_inode)
2963 {
2964         u32 sid = current_sid();
2965         struct common_audit_data ad;
2966         struct inode_security_struct *isec;
2967         int rc;
2968
2969         if (unlikely(!selinux_initialized()))
2970                 return 0;
2971
2972         isec = selinux_inode(inode);
2973
2974         /*
2975          * We only get here once per ephemeral inode.  The inode has
2976          * been initialized via inode_alloc_security but is otherwise
2977          * untouched.
2978          */
2979
2980         if (context_inode) {
2981                 struct inode_security_struct *context_isec =
2982                         selinux_inode(context_inode);
2983                 if (context_isec->initialized != LABEL_INITIALIZED) {
2984                         pr_err("SELinux:  context_inode is not initialized\n");
2985                         return -EACCES;
2986                 }
2987
2988                 isec->sclass = context_isec->sclass;
2989                 isec->sid = context_isec->sid;
2990         } else {
2991                 isec->sclass = SECCLASS_ANON_INODE;
2992                 rc = security_transition_sid(
2993                         sid, sid,
2994                         isec->sclass, name, &isec->sid);
2995                 if (rc)
2996                         return rc;
2997         }
2998
2999         isec->initialized = LABEL_INITIALIZED;
3000         /*
3001          * Now that we've initialized security, check whether we're
3002          * allowed to actually create this type of anonymous inode.
3003          */
3004
3005         ad.type = LSM_AUDIT_DATA_ANONINODE;
3006         ad.u.anonclass = name ? (const char *)name->name : "?";
3007
3008         return avc_has_perm(sid,
3009                             isec->sid,
3010                             isec->sclass,
3011                             FILE__CREATE,
3012                             &ad);
3013 }
3014
3015 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3016 {
3017         return may_create(dir, dentry, SECCLASS_FILE);
3018 }
3019
3020 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3021 {
3022         return may_link(dir, old_dentry, MAY_LINK);
3023 }
3024
3025 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3026 {
3027         return may_link(dir, dentry, MAY_UNLINK);
3028 }
3029
3030 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3031 {
3032         return may_create(dir, dentry, SECCLASS_LNK_FILE);
3033 }
3034
3035 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3036 {
3037         return may_create(dir, dentry, SECCLASS_DIR);
3038 }
3039
3040 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3041 {
3042         return may_link(dir, dentry, MAY_RMDIR);
3043 }
3044
3045 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3046 {
3047         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3048 }
3049
3050 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3051                                 struct inode *new_inode, struct dentry *new_dentry)
3052 {
3053         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3054 }
3055
3056 static int selinux_inode_readlink(struct dentry *dentry)
3057 {
3058         const struct cred *cred = current_cred();
3059
3060         return dentry_has_perm(cred, dentry, FILE__READ);
3061 }
3062
3063 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3064                                      bool rcu)
3065 {
3066         struct common_audit_data ad;
3067         struct inode_security_struct *isec;
3068         u32 sid = current_sid();
3069
3070         ad.type = LSM_AUDIT_DATA_DENTRY;
3071         ad.u.dentry = dentry;
3072         isec = inode_security_rcu(inode, rcu);
3073         if (IS_ERR(isec))
3074                 return PTR_ERR(isec);
3075
3076         return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3077 }
3078
3079 static noinline int audit_inode_permission(struct inode *inode,
3080                                            u32 perms, u32 audited, u32 denied,
3081                                            int result)
3082 {
3083         struct common_audit_data ad;
3084         struct inode_security_struct *isec = selinux_inode(inode);
3085
3086         ad.type = LSM_AUDIT_DATA_INODE;
3087         ad.u.inode = inode;
3088
3089         return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3090                             audited, denied, result, &ad);
3091 }
3092
3093 static int selinux_inode_permission(struct inode *inode, int mask)
3094 {
3095         u32 perms;
3096         bool from_access;
3097         bool no_block = mask & MAY_NOT_BLOCK;
3098         struct inode_security_struct *isec;
3099         u32 sid = current_sid();
3100         struct av_decision avd;
3101         int rc, rc2;
3102         u32 audited, denied;
3103
3104         from_access = mask & MAY_ACCESS;
3105         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3106
3107         /* No permission to check.  Existence test. */
3108         if (!mask)
3109                 return 0;
3110
3111         if (unlikely(IS_PRIVATE(inode)))
3112                 return 0;
3113
3114         perms = file_mask_to_av(inode->i_mode, mask);
3115
3116         isec = inode_security_rcu(inode, no_block);
3117         if (IS_ERR(isec))
3118                 return PTR_ERR(isec);
3119
3120         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3121                                   &avd);
3122         audited = avc_audit_required(perms, &avd, rc,
3123                                      from_access ? FILE__AUDIT_ACCESS : 0,
3124                                      &denied);
3125         if (likely(!audited))
3126                 return rc;
3127
3128         rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3129         if (rc2)
3130                 return rc2;
3131         return rc;
3132 }
3133
3134 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
3135                                  struct iattr *iattr)
3136 {
3137         const struct cred *cred = current_cred();
3138         struct inode *inode = d_backing_inode(dentry);
3139         unsigned int ia_valid = iattr->ia_valid;
3140         __u32 av = FILE__WRITE;
3141
3142         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3143         if (ia_valid & ATTR_FORCE) {
3144                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3145                               ATTR_FORCE);
3146                 if (!ia_valid)
3147                         return 0;
3148         }
3149
3150         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3151                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3152                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3153
3154         if (selinux_policycap_openperm() &&
3155             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3156             (ia_valid & ATTR_SIZE) &&
3157             !(ia_valid & ATTR_FILE))
3158                 av |= FILE__OPEN;
3159
3160         return dentry_has_perm(cred, dentry, av);
3161 }
3162
3163 static int selinux_inode_getattr(const struct path *path)
3164 {
3165         return path_has_perm(current_cred(), path, FILE__GETATTR);
3166 }
3167
3168 static bool has_cap_mac_admin(bool audit)
3169 {
3170         const struct cred *cred = current_cred();
3171         unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3172
3173         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3174                 return false;
3175         if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3176                 return false;
3177         return true;
3178 }
3179
3180 /**
3181  * selinux_inode_xattr_skipcap - Skip the xattr capability checks?
3182  * @name: name of the xattr
3183  *
3184  * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs
3185  * named @name; the LSM layer should avoid enforcing any traditional
3186  * capability based access controls on this xattr.  Returns 0 to indicate that
3187  * SELinux does not "own" the access control rights to xattrs named @name and is
3188  * deferring to the LSM layer for further access controls, including capability
3189  * based controls.
3190  */
3191 static int selinux_inode_xattr_skipcap(const char *name)
3192 {
3193         /* require capability check if not a selinux xattr */
3194         return !strcmp(name, XATTR_NAME_SELINUX);
3195 }
3196
3197 static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3198                                   struct dentry *dentry, const char *name,
3199                                   const void *value, size_t size, int flags)
3200 {
3201         struct inode *inode = d_backing_inode(dentry);
3202         struct inode_security_struct *isec;
3203         struct superblock_security_struct *sbsec;
3204         struct common_audit_data ad;
3205         u32 newsid, sid = current_sid();
3206         int rc = 0;
3207
3208         /* if not a selinux xattr, only check the ordinary setattr perm */
3209         if (strcmp(name, XATTR_NAME_SELINUX))
3210                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3211
3212         if (!selinux_initialized())
3213                 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3214
3215         sbsec = selinux_superblock(inode->i_sb);
3216         if (!(sbsec->flags & SBLABEL_MNT))
3217                 return -EOPNOTSUPP;
3218
3219         if (!inode_owner_or_capable(idmap, inode))
3220                 return -EPERM;
3221
3222         ad.type = LSM_AUDIT_DATA_DENTRY;
3223         ad.u.dentry = dentry;
3224
3225         isec = backing_inode_security(dentry);
3226         rc = avc_has_perm(sid, isec->sid, isec->sclass,
3227                           FILE__RELABELFROM, &ad);
3228         if (rc)
3229                 return rc;
3230
3231         rc = security_context_to_sid(value, size, &newsid,
3232                                      GFP_KERNEL);
3233         if (rc == -EINVAL) {
3234                 if (!has_cap_mac_admin(true)) {
3235                         struct audit_buffer *ab;
3236                         size_t audit_size;
3237
3238                         /* We strip a nul only if it is at the end, otherwise the
3239                          * context contains a nul and we should audit that */
3240                         if (value) {
3241                                 const char *str = value;
3242
3243                                 if (str[size - 1] == '\0')
3244                                         audit_size = size - 1;
3245                                 else
3246                                         audit_size = size;
3247                         } else {
3248                                 audit_size = 0;
3249                         }
3250                         ab = audit_log_start(audit_context(),
3251                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3252                         if (!ab)
3253                                 return rc;
3254                         audit_log_format(ab, "op=setxattr invalid_context=");
3255                         audit_log_n_untrustedstring(ab, value, audit_size);
3256                         audit_log_end(ab);
3257
3258                         return rc;
3259                 }
3260                 rc = security_context_to_sid_force(value,
3261                                                    size, &newsid);
3262         }
3263         if (rc)
3264                 return rc;
3265
3266         rc = avc_has_perm(sid, newsid, isec->sclass,
3267                           FILE__RELABELTO, &ad);
3268         if (rc)
3269                 return rc;
3270
3271         rc = security_validate_transition(isec->sid, newsid,
3272                                           sid, isec->sclass);
3273         if (rc)
3274                 return rc;
3275
3276         return avc_has_perm(newsid,
3277                             sbsec->sid,
3278                             SECCLASS_FILESYSTEM,
3279                             FILESYSTEM__ASSOCIATE,
3280                             &ad);
3281 }
3282
3283 static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3284                                  struct dentry *dentry, const char *acl_name,
3285                                  struct posix_acl *kacl)
3286 {
3287         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3288 }
3289
3290 static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3291                                  struct dentry *dentry, const char *acl_name)
3292 {
3293         return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3294 }
3295
3296 static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3297                                     struct dentry *dentry, const char *acl_name)
3298 {
3299         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3300 }
3301
3302 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3303                                         const void *value, size_t size,
3304                                         int flags)
3305 {
3306         struct inode *inode = d_backing_inode(dentry);
3307         struct inode_security_struct *isec;
3308         u32 newsid;
3309         int rc;
3310
3311         if (strcmp(name, XATTR_NAME_SELINUX)) {
3312                 /* Not an attribute we recognize, so nothing to do. */
3313                 return;
3314         }
3315
3316         if (!selinux_initialized()) {
3317                 /* If we haven't even been initialized, then we can't validate
3318                  * against a policy, so leave the label as invalid. It may
3319                  * resolve to a valid label on the next revalidation try if
3320                  * we've since initialized.
3321                  */
3322                 return;
3323         }
3324
3325         rc = security_context_to_sid_force(value, size,
3326                                            &newsid);
3327         if (rc) {
3328                 pr_err("SELinux:  unable to map context to SID"
3329                        "for (%s, %lu), rc=%d\n",
3330                        inode->i_sb->s_id, inode->i_ino, -rc);
3331                 return;
3332         }
3333
3334         isec = backing_inode_security(dentry);
3335         spin_lock(&isec->lock);
3336         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3337         isec->sid = newsid;
3338         isec->initialized = LABEL_INITIALIZED;
3339         spin_unlock(&isec->lock);
3340 }
3341
3342 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3343 {
3344         const struct cred *cred = current_cred();
3345
3346         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3347 }
3348
3349 static int selinux_inode_listxattr(struct dentry *dentry)
3350 {
3351         const struct cred *cred = current_cred();
3352
3353         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3354 }
3355
3356 static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3357                                      struct dentry *dentry, const char *name)
3358 {
3359         /* if not a selinux xattr, only check the ordinary setattr perm */
3360         if (strcmp(name, XATTR_NAME_SELINUX))
3361                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3362
3363         if (!selinux_initialized())
3364                 return 0;
3365
3366         /* No one is allowed to remove a SELinux security label.
3367            You can change the label, but all data must be labeled. */
3368         return -EACCES;
3369 }
3370
3371 static int selinux_path_notify(const struct path *path, u64 mask,
3372                                                 unsigned int obj_type)
3373 {
3374         int ret;
3375         u32 perm;
3376
3377         struct common_audit_data ad;
3378
3379         ad.type = LSM_AUDIT_DATA_PATH;
3380         ad.u.path = *path;
3381
3382         /*
3383          * Set permission needed based on the type of mark being set.
3384          * Performs an additional check for sb watches.
3385          */
3386         switch (obj_type) {
3387         case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3388                 perm = FILE__WATCH_MOUNT;
3389                 break;
3390         case FSNOTIFY_OBJ_TYPE_SB:
3391                 perm = FILE__WATCH_SB;
3392                 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3393                                                 FILESYSTEM__WATCH, &ad);
3394                 if (ret)
3395                         return ret;
3396                 break;
3397         case FSNOTIFY_OBJ_TYPE_INODE:
3398                 perm = FILE__WATCH;
3399                 break;
3400         default:
3401                 return -EINVAL;
3402         }
3403
3404         /* blocking watches require the file:watch_with_perm permission */
3405         if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3406                 perm |= FILE__WATCH_WITH_PERM;
3407
3408         /* watches on read-like events need the file:watch_reads permission */
3409         if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3410                 perm |= FILE__WATCH_READS;
3411
3412         return path_has_perm(current_cred(), path, perm);
3413 }
3414
3415 /*
3416  * Copy the inode security context value to the user.
3417  *
3418  * Permission check is handled by selinux_inode_getxattr hook.
3419  */
3420 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3421                                      struct inode *inode, const char *name,
3422                                      void **buffer, bool alloc)
3423 {
3424         u32 size;
3425         int error;
3426         char *context = NULL;
3427         struct inode_security_struct *isec;
3428
3429         /*
3430          * If we're not initialized yet, then we can't validate contexts, so
3431          * just let vfs_getxattr fall back to using the on-disk xattr.
3432          */
3433         if (!selinux_initialized() ||
3434             strcmp(name, XATTR_SELINUX_SUFFIX))
3435                 return -EOPNOTSUPP;
3436
3437         /*
3438          * If the caller has CAP_MAC_ADMIN, then get the raw context
3439          * value even if it is not defined by current policy; otherwise,
3440          * use the in-core value under current policy.
3441          * Use the non-auditing forms of the permission checks since
3442          * getxattr may be called by unprivileged processes commonly
3443          * and lack of permission just means that we fall back to the
3444          * in-core context value, not a denial.
3445          */
3446         isec = inode_security(inode);
3447         if (has_cap_mac_admin(false))
3448                 error = security_sid_to_context_force(isec->sid, &context,
3449                                                       &size);
3450         else
3451                 error = security_sid_to_context(isec->sid,
3452                                                 &context, &size);
3453         if (error)
3454                 return error;
3455         error = size;
3456         if (alloc) {
3457                 *buffer = context;
3458                 goto out_nofree;
3459         }
3460         kfree(context);
3461 out_nofree:
3462         return error;
3463 }
3464
3465 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3466                                      const void *value, size_t size, int flags)
3467 {
3468         struct inode_security_struct *isec = inode_security_novalidate(inode);
3469         struct superblock_security_struct *sbsec;
3470         u32 newsid;
3471         int rc;
3472
3473         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3474                 return -EOPNOTSUPP;
3475
3476         sbsec = selinux_superblock(inode->i_sb);
3477         if (!(sbsec->flags & SBLABEL_MNT))
3478                 return -EOPNOTSUPP;
3479
3480         if (!value || !size)
3481                 return -EACCES;
3482
3483         rc = security_context_to_sid(value, size, &newsid,
3484                                      GFP_KERNEL);
3485         if (rc)
3486                 return rc;
3487
3488         spin_lock(&isec->lock);
3489         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3490         isec->sid = newsid;
3491         isec->initialized = LABEL_INITIALIZED;
3492         spin_unlock(&isec->lock);
3493         return 0;
3494 }
3495
3496 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3497 {
3498         const int len = sizeof(XATTR_NAME_SELINUX);
3499
3500         if (!selinux_initialized())
3501                 return 0;
3502
3503         if (buffer && len <= buffer_size)
3504                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3505         return len;
3506 }
3507
3508 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3509 {
3510         struct inode_security_struct *isec = inode_security_novalidate(inode);
3511         *secid = isec->sid;
3512 }
3513
3514 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3515 {
3516         u32 sid;
3517         struct task_security_struct *tsec;
3518         struct cred *new_creds = *new;
3519
3520         if (new_creds == NULL) {
3521                 new_creds = prepare_creds();
3522                 if (!new_creds)
3523                         return -ENOMEM;
3524         }
3525
3526         tsec = selinux_cred(new_creds);
3527         /* Get label from overlay inode and set it in create_sid */
3528         selinux_inode_getsecid(d_inode(src), &sid);
3529         tsec->create_sid = sid;
3530         *new = new_creds;
3531         return 0;
3532 }
3533
3534 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name)
3535 {
3536         /* The copy_up hook above sets the initial context on an inode, but we
3537          * don't then want to overwrite it by blindly copying all the lower
3538          * xattrs up.  Instead, filter out SELinux-related xattrs following
3539          * policy load.
3540          */
3541         if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0)
3542                 return 1; /* Discard */
3543         /*
3544          * Any other attribute apart from SELINUX is not claimed, supported
3545          * by selinux.
3546          */
3547         return -EOPNOTSUPP;
3548 }
3549
3550 /* kernfs node operations */
3551
3552 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3553                                         struct kernfs_node *kn)
3554 {
3555         const struct task_security_struct *tsec = selinux_cred(current_cred());
3556         u32 parent_sid, newsid, clen;
3557         int rc;
3558         char *context;
3559
3560         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3561         if (rc == -ENODATA)
3562                 return 0;
3563         else if (rc < 0)
3564                 return rc;
3565
3566         clen = (u32)rc;
3567         context = kmalloc(clen, GFP_KERNEL);
3568         if (!context)
3569                 return -ENOMEM;
3570
3571         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3572         if (rc < 0) {
3573                 kfree(context);
3574                 return rc;
3575         }
3576
3577         rc = security_context_to_sid(context, clen, &parent_sid,
3578                                      GFP_KERNEL);
3579         kfree(context);
3580         if (rc)
3581                 return rc;
3582
3583         if (tsec->create_sid) {
3584                 newsid = tsec->create_sid;
3585         } else {
3586                 u16 secclass = inode_mode_to_security_class(kn->mode);
3587                 struct qstr q;
3588
3589                 q.name = kn->name;
3590                 q.hash_len = hashlen_string(kn_dir, kn->name);
3591
3592                 rc = security_transition_sid(tsec->sid,
3593                                              parent_sid, secclass, &q,
3594                                              &newsid);
3595                 if (rc)
3596                         return rc;
3597         }
3598
3599         rc = security_sid_to_context_force(newsid,
3600                                            &context, &clen);
3601         if (rc)
3602                 return rc;
3603
3604         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3605                               XATTR_CREATE);
3606         kfree(context);
3607         return rc;
3608 }
3609
3610
3611 /* file security operations */
3612
3613 static int selinux_revalidate_file_permission(struct file *file, int mask)
3614 {
3615         const struct cred *cred = current_cred();
3616         struct inode *inode = file_inode(file);
3617
3618         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3619         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3620                 mask |= MAY_APPEND;
3621
3622         return file_has_perm(cred, file,
3623                              file_mask_to_av(inode->i_mode, mask));
3624 }
3625
3626 static int selinux_file_permission(struct file *file, int mask)
3627 {
3628         struct inode *inode = file_inode(file);
3629         struct file_security_struct *fsec = selinux_file(file);
3630         struct inode_security_struct *isec;
3631         u32 sid = current_sid();
3632
3633         if (!mask)
3634                 /* No permission to check.  Existence test. */
3635                 return 0;
3636
3637         isec = inode_security(inode);
3638         if (sid == fsec->sid && fsec->isid == isec->sid &&
3639             fsec->pseqno == avc_policy_seqno())
3640                 /* No change since file_open check. */
3641                 return 0;
3642
3643         return selinux_revalidate_file_permission(file, mask);
3644 }
3645
3646 static int selinux_file_alloc_security(struct file *file)
3647 {
3648         struct file_security_struct *fsec = selinux_file(file);
3649         u32 sid = current_sid();
3650
3651         fsec->sid = sid;
3652         fsec->fown_sid = sid;
3653
3654         return 0;
3655 }
3656
3657 /*
3658  * Check whether a task has the ioctl permission and cmd
3659  * operation to an inode.
3660  */
3661 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3662                 u32 requested, u16 cmd)
3663 {
3664         struct common_audit_data ad;
3665         struct file_security_struct *fsec = selinux_file(file);
3666         struct inode *inode = file_inode(file);
3667         struct inode_security_struct *isec;
3668         struct lsm_ioctlop_audit ioctl;
3669         u32 ssid = cred_sid(cred);
3670         int rc;
3671         u8 driver = cmd >> 8;
3672         u8 xperm = cmd & 0xff;
3673
3674         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3675         ad.u.op = &ioctl;
3676         ad.u.op->cmd = cmd;
3677         ad.u.op->path = file->f_path;
3678
3679         if (ssid != fsec->sid) {
3680                 rc = avc_has_perm(ssid, fsec->sid,
3681                                 SECCLASS_FD,
3682                                 FD__USE,
3683                                 &ad);
3684                 if (rc)
3685                         goto out;
3686         }
3687
3688         if (unlikely(IS_PRIVATE(inode)))
3689                 return 0;
3690
3691         isec = inode_security(inode);
3692         rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3693                                     requested, driver, xperm, &ad);
3694 out:
3695         return rc;
3696 }
3697
3698 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3699                               unsigned long arg)
3700 {
3701         const struct cred *cred = current_cred();
3702         int error = 0;
3703
3704         switch (cmd) {
3705         case FIONREAD:
3706         case FIBMAP:
3707         case FIGETBSZ:
3708         case FS_IOC_GETFLAGS:
3709         case FS_IOC_GETVERSION:
3710                 error = file_has_perm(cred, file, FILE__GETATTR);
3711                 break;
3712
3713         case FS_IOC_SETFLAGS:
3714         case FS_IOC_SETVERSION:
3715                 error = file_has_perm(cred, file, FILE__SETATTR);
3716                 break;
3717
3718         /* sys_ioctl() checks */
3719         case FIONBIO:
3720         case FIOASYNC:
3721                 error = file_has_perm(cred, file, 0);
3722                 break;
3723
3724         case KDSKBENT:
3725         case KDSKBSENT:
3726                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3727                                             CAP_OPT_NONE, true);
3728                 break;
3729
3730         case FIOCLEX:
3731         case FIONCLEX:
3732                 if (!selinux_policycap_ioctl_skip_cloexec())
3733                         error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3734                 break;
3735
3736         /* default case assumes that the command will go
3737          * to the file's ioctl() function.
3738          */
3739         default:
3740                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3741         }
3742         return error;
3743 }
3744
3745 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3746                               unsigned long arg)
3747 {
3748         /*
3749          * If we are in a 64-bit kernel running 32-bit userspace, we need to
3750          * make sure we don't compare 32-bit flags to 64-bit flags.
3751          */
3752         switch (cmd) {
3753         case FS_IOC32_GETFLAGS:
3754                 cmd = FS_IOC_GETFLAGS;
3755                 break;
3756         case FS_IOC32_SETFLAGS:
3757                 cmd = FS_IOC_SETFLAGS;
3758                 break;
3759         case FS_IOC32_GETVERSION:
3760                 cmd = FS_IOC_GETVERSION;
3761                 break;
3762         case FS_IOC32_SETVERSION:
3763                 cmd = FS_IOC_SETVERSION;
3764                 break;
3765         default:
3766                 break;
3767         }
3768
3769         return selinux_file_ioctl(file, cmd, arg);
3770 }
3771
3772 static int default_noexec __ro_after_init;
3773
3774 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3775 {
3776         const struct cred *cred = current_cred();
3777         u32 sid = cred_sid(cred);
3778         int rc = 0;
3779
3780         if (default_noexec &&
3781             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3782                                    (!shared && (prot & PROT_WRITE)))) {
3783                 /*
3784                  * We are making executable an anonymous mapping or a
3785                  * private file mapping that will also be writable.
3786                  * This has an additional check.
3787                  */
3788                 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3789                                   PROCESS__EXECMEM, NULL);
3790                 if (rc)
3791                         goto error;
3792         }
3793
3794         if (file) {
3795                 /* read access is always possible with a mapping */
3796                 u32 av = FILE__READ;
3797
3798                 /* write access only matters if the mapping is shared */
3799                 if (shared && (prot & PROT_WRITE))
3800                         av |= FILE__WRITE;
3801
3802                 if (prot & PROT_EXEC)
3803                         av |= FILE__EXECUTE;
3804
3805                 return file_has_perm(cred, file, av);
3806         }
3807
3808 error:
3809         return rc;
3810 }
3811
3812 static int selinux_mmap_addr(unsigned long addr)
3813 {
3814         int rc = 0;
3815
3816         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3817                 u32 sid = current_sid();
3818                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3819                                   MEMPROTECT__MMAP_ZERO, NULL);
3820         }
3821
3822         return rc;
3823 }
3824
3825 static int selinux_mmap_file(struct file *file,
3826                              unsigned long reqprot __always_unused,
3827                              unsigned long prot, unsigned long flags)
3828 {
3829         struct common_audit_data ad;
3830         int rc;
3831
3832         if (file) {
3833                 ad.type = LSM_AUDIT_DATA_FILE;
3834                 ad.u.file = file;
3835                 rc = inode_has_perm(current_cred(), file_inode(file),
3836                                     FILE__MAP, &ad);
3837                 if (rc)
3838                         return rc;
3839         }
3840
3841         return file_map_prot_check(file, prot,
3842                                    (flags & MAP_TYPE) == MAP_SHARED);
3843 }
3844
3845 static int selinux_file_mprotect(struct vm_area_struct *vma,
3846                                  unsigned long reqprot __always_unused,
3847                                  unsigned long prot)
3848 {
3849         const struct cred *cred = current_cred();
3850         u32 sid = cred_sid(cred);
3851
3852         if (default_noexec &&
3853             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3854                 int rc = 0;
3855                 /*
3856                  * We don't use the vma_is_initial_heap() helper as it has
3857                  * a history of problems and is currently broken on systems
3858                  * where there is no heap, e.g. brk == start_brk.  Before
3859                  * replacing the conditional below with vma_is_initial_heap(),
3860                  * or something similar, please ensure that the logic is the
3861                  * same as what we have below or you have tested every possible
3862                  * corner case you can think to test.
3863                  */
3864                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3865                     vma->vm_end <= vma->vm_mm->brk) {
3866                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3867                                           PROCESS__EXECHEAP, NULL);
3868                 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3869                             vma_is_stack_for_current(vma))) {
3870                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3871                                           PROCESS__EXECSTACK, NULL);
3872                 } else if (vma->vm_file && vma->anon_vma) {
3873                         /*
3874                          * We are making executable a file mapping that has
3875                          * had some COW done. Since pages might have been
3876                          * written, check ability to execute the possibly
3877                          * modified content.  This typically should only
3878                          * occur for text relocations.
3879                          */
3880                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3881                 }
3882                 if (rc)
3883                         return rc;
3884         }
3885
3886         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3887 }
3888
3889 static int selinux_file_lock(struct file *file, unsigned int cmd)
3890 {
3891         const struct cred *cred = current_cred();
3892
3893         return file_has_perm(cred, file, FILE__LOCK);
3894 }
3895
3896 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3897                               unsigned long arg)
3898 {
3899         const struct cred *cred = current_cred();
3900         int err = 0;
3901
3902         switch (cmd) {
3903         case F_SETFL:
3904                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3905                         err = file_has_perm(cred, file, FILE__WRITE);
3906                         break;
3907                 }
3908                 fallthrough;
3909         case F_SETOWN:
3910         case F_SETSIG:
3911         case F_GETFL:
3912         case F_GETOWN:
3913         case F_GETSIG:
3914         case F_GETOWNER_UIDS:
3915                 /* Just check FD__USE permission */
3916                 err = file_has_perm(cred, file, 0);
3917                 break;
3918         case F_GETLK:
3919         case F_SETLK:
3920         case F_SETLKW:
3921         case F_OFD_GETLK:
3922         case F_OFD_SETLK:
3923         case F_OFD_SETLKW:
3924 #if BITS_PER_LONG == 32
3925         case F_GETLK64:
3926         case F_SETLK64:
3927         case F_SETLKW64:
3928 #endif
3929                 err = file_has_perm(cred, file, FILE__LOCK);
3930                 break;
3931         }
3932
3933         return err;
3934 }
3935
3936 static void selinux_file_set_fowner(struct file *file)
3937 {
3938         struct file_security_struct *fsec;
3939
3940         fsec = selinux_file(file);
3941         fsec->fown_sid = current_sid();
3942 }
3943
3944 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3945                                        struct fown_struct *fown, int signum)
3946 {
3947         struct file *file;
3948         u32 sid = task_sid_obj(tsk);
3949         u32 perm;
3950         struct file_security_struct *fsec;
3951
3952         /* struct fown_struct is never outside the context of a struct file */
3953         file = fown->file;
3954
3955         fsec = selinux_file(file);
3956
3957         if (!signum)
3958                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3959         else
3960                 perm = signal_to_av(signum);
3961
3962         return avc_has_perm(fsec->fown_sid, sid,
3963                             SECCLASS_PROCESS, perm, NULL);
3964 }
3965
3966 static int selinux_file_receive(struct file *file)
3967 {
3968         const struct cred *cred = current_cred();
3969
3970         return file_has_perm(cred, file, file_to_av(file));
3971 }
3972
3973 static int selinux_file_open(struct file *file)
3974 {
3975         struct file_security_struct *fsec;
3976         struct inode_security_struct *isec;
3977
3978         fsec = selinux_file(file);
3979         isec = inode_security(file_inode(file));
3980         /*
3981          * Save inode label and policy sequence number
3982          * at open-time so that selinux_file_permission
3983          * can determine whether revalidation is necessary.
3984          * Task label is already saved in the file security
3985          * struct as its SID.
3986          */
3987         fsec->isid = isec->sid;
3988         fsec->pseqno = avc_policy_seqno();
3989         /*
3990          * Since the inode label or policy seqno may have changed
3991          * between the selinux_inode_permission check and the saving
3992          * of state above, recheck that access is still permitted.
3993          * Otherwise, access might never be revalidated against the
3994          * new inode label or new policy.
3995          * This check is not redundant - do not remove.
3996          */
3997         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3998 }
3999
4000 /* task security operations */
4001
4002 static int selinux_task_alloc(struct task_struct *task,
4003                               unsigned long clone_flags)
4004 {
4005         u32 sid = current_sid();
4006
4007         return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4008 }
4009
4010 /*
4011  * prepare a new set of credentials for modification
4012  */
4013 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4014                                 gfp_t gfp)
4015 {
4016         const struct task_security_struct *old_tsec = selinux_cred(old);
4017         struct task_security_struct *tsec = selinux_cred(new);
4018
4019         *tsec = *old_tsec;
4020         return 0;
4021 }
4022
4023 /*
4024  * transfer the SELinux data to a blank set of creds
4025  */
4026 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4027 {
4028         const struct task_security_struct *old_tsec = selinux_cred(old);
4029         struct task_security_struct *tsec = selinux_cred(new);
4030
4031         *tsec = *old_tsec;
4032 }
4033
4034 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4035 {
4036         *secid = cred_sid(c);
4037 }
4038
4039 /*
4040  * set the security data for a kernel service
4041  * - all the creation contexts are set to unlabelled
4042  */
4043 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4044 {
4045         struct task_security_struct *tsec = selinux_cred(new);
4046         u32 sid = current_sid();
4047         int ret;
4048
4049         ret = avc_has_perm(sid, secid,
4050                            SECCLASS_KERNEL_SERVICE,
4051                            KERNEL_SERVICE__USE_AS_OVERRIDE,
4052                            NULL);
4053         if (ret == 0) {
4054                 tsec->sid = secid;
4055                 tsec->create_sid = 0;
4056                 tsec->keycreate_sid = 0;
4057                 tsec->sockcreate_sid = 0;
4058         }
4059         return ret;
4060 }
4061
4062 /*
4063  * set the file creation context in a security record to the same as the
4064  * objective context of the specified inode
4065  */
4066 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4067 {
4068         struct inode_security_struct *isec = inode_security(inode);
4069         struct task_security_struct *tsec = selinux_cred(new);
4070         u32 sid = current_sid();
4071         int ret;
4072
4073         ret = avc_has_perm(sid, isec->sid,
4074                            SECCLASS_KERNEL_SERVICE,
4075                            KERNEL_SERVICE__CREATE_FILES_AS,
4076                            NULL);
4077
4078         if (ret == 0)
4079                 tsec->create_sid = isec->sid;
4080         return ret;
4081 }
4082
4083 static int selinux_kernel_module_request(char *kmod_name)
4084 {
4085         struct common_audit_data ad;
4086
4087         ad.type = LSM_AUDIT_DATA_KMOD;
4088         ad.u.kmod_name = kmod_name;
4089
4090         return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4091                             SYSTEM__MODULE_REQUEST, &ad);
4092 }
4093
4094 static int selinux_kernel_module_from_file(struct file *file)
4095 {
4096         struct common_audit_data ad;
4097         struct inode_security_struct *isec;
4098         struct file_security_struct *fsec;
4099         u32 sid = current_sid();
4100         int rc;
4101
4102         /* init_module */
4103         if (file == NULL)
4104                 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4105                                         SYSTEM__MODULE_LOAD, NULL);
4106
4107         /* finit_module */
4108
4109         ad.type = LSM_AUDIT_DATA_FILE;
4110         ad.u.file = file;
4111
4112         fsec = selinux_file(file);
4113         if (sid != fsec->sid) {
4114                 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4115                 if (rc)
4116                         return rc;
4117         }
4118
4119         isec = inode_security(file_inode(file));
4120         return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4121                                 SYSTEM__MODULE_LOAD, &ad);
4122 }
4123
4124 static int selinux_kernel_read_file(struct file *file,
4125                                     enum kernel_read_file_id id,
4126                                     bool contents)
4127 {
4128         int rc = 0;
4129
4130         switch (id) {
4131         case READING_MODULE:
4132                 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4133                 break;
4134         default:
4135                 break;
4136         }
4137
4138         return rc;
4139 }
4140
4141 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4142 {
4143         int rc = 0;
4144
4145         switch (id) {
4146         case LOADING_MODULE:
4147                 rc = selinux_kernel_module_from_file(NULL);
4148                 break;
4149         default:
4150                 break;
4151         }
4152
4153         return rc;
4154 }
4155
4156 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4157 {
4158         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4159                             PROCESS__SETPGID, NULL);
4160 }
4161
4162 static int selinux_task_getpgid(struct task_struct *p)
4163 {
4164         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4165                             PROCESS__GETPGID, NULL);
4166 }
4167
4168 static int selinux_task_getsid(struct task_struct *p)
4169 {
4170         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4171                             PROCESS__GETSESSION, NULL);
4172 }
4173
4174 static void selinux_current_getsecid_subj(u32 *secid)
4175 {
4176         *secid = current_sid();
4177 }
4178
4179 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4180 {
4181         *secid = task_sid_obj(p);
4182 }
4183
4184 static int selinux_task_setnice(struct task_struct *p, int nice)
4185 {
4186         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4187                             PROCESS__SETSCHED, NULL);
4188 }
4189
4190 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4191 {
4192         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4193                             PROCESS__SETSCHED, NULL);
4194 }
4195
4196 static int selinux_task_getioprio(struct task_struct *p)
4197 {
4198         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4199                             PROCESS__GETSCHED, NULL);
4200 }
4201
4202 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4203                                 unsigned int flags)
4204 {
4205         u32 av = 0;
4206
4207         if (!flags)
4208                 return 0;
4209         if (flags & LSM_PRLIMIT_WRITE)
4210                 av |= PROCESS__SETRLIMIT;
4211         if (flags & LSM_PRLIMIT_READ)
4212                 av |= PROCESS__GETRLIMIT;
4213         return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4214                             SECCLASS_PROCESS, av, NULL);
4215 }
4216
4217 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4218                 struct rlimit *new_rlim)
4219 {
4220         struct rlimit *old_rlim = p->signal->rlim + resource;
4221
4222         /* Control the ability to change the hard limit (whether
4223            lowering or raising it), so that the hard limit can
4224            later be used as a safe reset point for the soft limit
4225            upon context transitions.  See selinux_bprm_committing_creds. */
4226         if (old_rlim->rlim_max != new_rlim->rlim_max)
4227                 return avc_has_perm(current_sid(), task_sid_obj(p),
4228                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4229
4230         return 0;
4231 }
4232
4233 static int selinux_task_setscheduler(struct task_struct *p)
4234 {
4235         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4236                             PROCESS__SETSCHED, NULL);
4237 }
4238
4239 static int selinux_task_getscheduler(struct task_struct *p)
4240 {
4241         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4242                             PROCESS__GETSCHED, NULL);
4243 }
4244
4245 static int selinux_task_movememory(struct task_struct *p)
4246 {
4247         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4248                             PROCESS__SETSCHED, NULL);
4249 }
4250
4251 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4252                                 int sig, const struct cred *cred)
4253 {
4254         u32 secid;
4255         u32 perm;
4256
4257         if (!sig)
4258                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4259         else
4260                 perm = signal_to_av(sig);
4261         if (!cred)
4262                 secid = current_sid();
4263         else
4264                 secid = cred_sid(cred);
4265         return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4266 }
4267
4268 static void selinux_task_to_inode(struct task_struct *p,
4269                                   struct inode *inode)
4270 {
4271         struct inode_security_struct *isec = selinux_inode(inode);
4272         u32 sid = task_sid_obj(p);
4273
4274         spin_lock(&isec->lock);
4275         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4276         isec->sid = sid;
4277         isec->initialized = LABEL_INITIALIZED;
4278         spin_unlock(&isec->lock);
4279 }
4280
4281 static int selinux_userns_create(const struct cred *cred)
4282 {
4283         u32 sid = current_sid();
4284
4285         return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4286                         USER_NAMESPACE__CREATE, NULL);
4287 }
4288
4289 /* Returns error only if unable to parse addresses */
4290 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4291                         struct common_audit_data *ad, u8 *proto)
4292 {
4293         int offset, ihlen, ret = -EINVAL;
4294         struct iphdr _iph, *ih;
4295
4296         offset = skb_network_offset(skb);
4297         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4298         if (ih == NULL)
4299                 goto out;
4300
4301         ihlen = ih->ihl * 4;
4302         if (ihlen < sizeof(_iph))
4303                 goto out;
4304
4305         ad->u.net->v4info.saddr = ih->saddr;
4306         ad->u.net->v4info.daddr = ih->daddr;
4307         ret = 0;
4308
4309         if (proto)
4310                 *proto = ih->protocol;
4311
4312         switch (ih->protocol) {
4313         case IPPROTO_TCP: {
4314                 struct tcphdr _tcph, *th;
4315
4316                 if (ntohs(ih->frag_off) & IP_OFFSET)
4317                         break;
4318
4319                 offset += ihlen;
4320                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4321                 if (th == NULL)
4322                         break;
4323
4324                 ad->u.net->sport = th->source;
4325                 ad->u.net->dport = th->dest;
4326                 break;
4327         }
4328
4329         case IPPROTO_UDP: {
4330                 struct udphdr _udph, *uh;
4331
4332                 if (ntohs(ih->frag_off) & IP_OFFSET)
4333                         break;
4334
4335                 offset += ihlen;
4336                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4337                 if (uh == NULL)
4338                         break;
4339
4340                 ad->u.net->sport = uh->source;
4341                 ad->u.net->dport = uh->dest;
4342                 break;
4343         }
4344
4345         case IPPROTO_DCCP: {
4346                 struct dccp_hdr _dccph, *dh;
4347
4348                 if (ntohs(ih->frag_off) & IP_OFFSET)
4349                         break;
4350
4351                 offset += ihlen;
4352                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4353                 if (dh == NULL)
4354                         break;
4355
4356                 ad->u.net->sport = dh->dccph_sport;
4357                 ad->u.net->dport = dh->dccph_dport;
4358                 break;
4359         }
4360
4361 #if IS_ENABLED(CONFIG_IP_SCTP)
4362         case IPPROTO_SCTP: {
4363                 struct sctphdr _sctph, *sh;
4364
4365                 if (ntohs(ih->frag_off) & IP_OFFSET)
4366                         break;
4367
4368                 offset += ihlen;
4369                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4370                 if (sh == NULL)
4371                         break;
4372
4373                 ad->u.net->sport = sh->source;
4374                 ad->u.net->dport = sh->dest;
4375                 break;
4376         }
4377 #endif
4378         default:
4379                 break;
4380         }
4381 out:
4382         return ret;
4383 }
4384
4385 #if IS_ENABLED(CONFIG_IPV6)
4386
4387 /* Returns error only if unable to parse addresses */
4388 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4389                         struct common_audit_data *ad, u8 *proto)
4390 {
4391         u8 nexthdr;
4392         int ret = -EINVAL, offset;
4393         struct ipv6hdr _ipv6h, *ip6;
4394         __be16 frag_off;
4395
4396         offset = skb_network_offset(skb);
4397         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4398         if (ip6 == NULL)
4399                 goto out;
4400
4401         ad->u.net->v6info.saddr = ip6->saddr;
4402         ad->u.net->v6info.daddr = ip6->daddr;
4403         ret = 0;
4404
4405         nexthdr = ip6->nexthdr;
4406         offset += sizeof(_ipv6h);
4407         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4408         if (offset < 0)
4409                 goto out;
4410
4411         if (proto)
4412                 *proto = nexthdr;
4413
4414         switch (nexthdr) {
4415         case IPPROTO_TCP: {
4416                 struct tcphdr _tcph, *th;
4417
4418                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4419                 if (th == NULL)
4420                         break;
4421
4422                 ad->u.net->sport = th->source;
4423                 ad->u.net->dport = th->dest;
4424                 break;
4425         }
4426
4427         case IPPROTO_UDP: {
4428                 struct udphdr _udph, *uh;
4429
4430                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4431                 if (uh == NULL)
4432                         break;
4433
4434                 ad->u.net->sport = uh->source;
4435                 ad->u.net->dport = uh->dest;
4436                 break;
4437         }
4438
4439         case IPPROTO_DCCP: {
4440                 struct dccp_hdr _dccph, *dh;
4441
4442                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4443                 if (dh == NULL)
4444                         break;
4445
4446                 ad->u.net->sport = dh->dccph_sport;
4447                 ad->u.net->dport = dh->dccph_dport;
4448                 break;
4449         }
4450
4451 #if IS_ENABLED(CONFIG_IP_SCTP)
4452         case IPPROTO_SCTP: {
4453                 struct sctphdr _sctph, *sh;
4454
4455                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4456                 if (sh == NULL)
4457                         break;
4458
4459                 ad->u.net->sport = sh->source;
4460                 ad->u.net->dport = sh->dest;
4461                 break;
4462         }
4463 #endif
4464         /* includes fragments */
4465         default:
4466                 break;
4467         }
4468 out:
4469         return ret;
4470 }
4471
4472 #endif /* IPV6 */
4473
4474 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4475                              char **_addrp, int src, u8 *proto)
4476 {
4477         char *addrp;
4478         int ret;
4479
4480         switch (ad->u.net->family) {
4481         case PF_INET:
4482                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4483                 if (ret)
4484                         goto parse_error;
4485                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4486                                        &ad->u.net->v4info.daddr);
4487                 goto okay;
4488
4489 #if IS_ENABLED(CONFIG_IPV6)
4490         case PF_INET6:
4491                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4492                 if (ret)
4493                         goto parse_error;
4494                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4495                                        &ad->u.net->v6info.daddr);
4496                 goto okay;
4497 #endif  /* IPV6 */
4498         default:
4499                 addrp = NULL;
4500                 goto okay;
4501         }
4502
4503 parse_error:
4504         pr_warn(
4505                "SELinux: failure in selinux_parse_skb(),"
4506                " unable to parse packet\n");
4507         return ret;
4508
4509 okay:
4510         if (_addrp)
4511                 *_addrp = addrp;
4512         return 0;
4513 }
4514
4515 /**
4516  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4517  * @skb: the packet
4518  * @family: protocol family
4519  * @sid: the packet's peer label SID
4520  *
4521  * Description:
4522  * Check the various different forms of network peer labeling and determine
4523  * the peer label/SID for the packet; most of the magic actually occurs in
4524  * the security server function security_net_peersid_cmp().  The function
4525  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4526  * or -EACCES if @sid is invalid due to inconsistencies with the different
4527  * peer labels.
4528  *
4529  */
4530 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4531 {
4532         int err;
4533         u32 xfrm_sid;
4534         u32 nlbl_sid;
4535         u32 nlbl_type;
4536
4537         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4538         if (unlikely(err))
4539                 return -EACCES;
4540         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4541         if (unlikely(err))
4542                 return -EACCES;
4543
4544         err = security_net_peersid_resolve(nlbl_sid,
4545                                            nlbl_type, xfrm_sid, sid);
4546         if (unlikely(err)) {
4547                 pr_warn(
4548                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4549                        " unable to determine packet's peer label\n");
4550                 return -EACCES;
4551         }
4552
4553         return 0;
4554 }
4555
4556 /**
4557  * selinux_conn_sid - Determine the child socket label for a connection
4558  * @sk_sid: the parent socket's SID
4559  * @skb_sid: the packet's SID
4560  * @conn_sid: the resulting connection SID
4561  *
4562  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4563  * combined with the MLS information from @skb_sid in order to create
4564  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4565  * of @sk_sid.  Returns zero on success, negative values on failure.
4566  *
4567  */
4568 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4569 {
4570         int err = 0;
4571
4572         if (skb_sid != SECSID_NULL)
4573                 err = security_sid_mls_copy(sk_sid, skb_sid,
4574                                             conn_sid);
4575         else
4576                 *conn_sid = sk_sid;
4577
4578         return err;
4579 }
4580
4581 /* socket security operations */
4582
4583 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4584                                  u16 secclass, u32 *socksid)
4585 {
4586         if (tsec->sockcreate_sid > SECSID_NULL) {
4587                 *socksid = tsec->sockcreate_sid;
4588                 return 0;
4589         }
4590
4591         return security_transition_sid(tsec->sid, tsec->sid,
4592                                        secclass, NULL, socksid);
4593 }
4594
4595 static int sock_has_perm(struct sock *sk, u32 perms)
4596 {
4597         struct sk_security_struct *sksec = sk->sk_security;
4598         struct common_audit_data ad;
4599         struct lsm_network_audit net;
4600
4601         if (sksec->sid == SECINITSID_KERNEL)
4602                 return 0;
4603
4604         /*
4605          * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4606          * inherited the kernel context from early boot used to be skipped
4607          * here, so preserve that behavior unless the capability is set.
4608          *
4609          * By setting the capability the policy signals that it is ready
4610          * for this quirk to be fixed. Note that sockets created by a kernel
4611          * thread or a usermode helper executed without a transition will
4612          * still be skipped in this check regardless of the policycap
4613          * setting.
4614          */
4615         if (!selinux_policycap_userspace_initial_context() &&
4616             sksec->sid == SECINITSID_INIT)
4617                 return 0;
4618
4619         ad_net_init_from_sk(&ad, &net, sk);
4620
4621         return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4622                             &ad);
4623 }
4624
4625 static int selinux_socket_create(int family, int type,
4626                                  int protocol, int kern)
4627 {
4628         const struct task_security_struct *tsec = selinux_cred(current_cred());
4629         u32 newsid;
4630         u16 secclass;
4631         int rc;
4632
4633         if (kern)
4634                 return 0;
4635
4636         secclass = socket_type_to_security_class(family, type, protocol);
4637         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4638         if (rc)
4639                 return rc;
4640
4641         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4642 }
4643
4644 static int selinux_socket_post_create(struct socket *sock, int family,
4645                                       int type, int protocol, int kern)
4646 {
4647         const struct task_security_struct *tsec = selinux_cred(current_cred());
4648         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4649         struct sk_security_struct *sksec;
4650         u16 sclass = socket_type_to_security_class(family, type, protocol);
4651         u32 sid = SECINITSID_KERNEL;
4652         int err = 0;
4653
4654         if (!kern) {
4655                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4656                 if (err)
4657                         return err;
4658         }
4659
4660         isec->sclass = sclass;
4661         isec->sid = sid;
4662         isec->initialized = LABEL_INITIALIZED;
4663
4664         if (sock->sk) {
4665                 sksec = sock->sk->sk_security;
4666                 sksec->sclass = sclass;
4667                 sksec->sid = sid;
4668                 /* Allows detection of the first association on this socket */
4669                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4670                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4671
4672                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4673         }
4674
4675         return err;
4676 }
4677
4678 static int selinux_socket_socketpair(struct socket *socka,
4679                                      struct socket *sockb)
4680 {
4681         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4682         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4683
4684         sksec_a->peer_sid = sksec_b->sid;
4685         sksec_b->peer_sid = sksec_a->sid;
4686
4687         return 0;
4688 }
4689
4690 /* Range of port numbers used to automatically bind.
4691    Need to determine whether we should perform a name_bind
4692    permission check between the socket and the port number. */
4693
4694 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4695 {
4696         struct sock *sk = sock->sk;
4697         struct sk_security_struct *sksec = sk->sk_security;
4698         u16 family;
4699         int err;
4700
4701         err = sock_has_perm(sk, SOCKET__BIND);
4702         if (err)
4703                 goto out;
4704
4705         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4706         family = sk->sk_family;
4707         if (family == PF_INET || family == PF_INET6) {
4708                 char *addrp;
4709                 struct common_audit_data ad;
4710                 struct lsm_network_audit net = {0,};
4711                 struct sockaddr_in *addr4 = NULL;
4712                 struct sockaddr_in6 *addr6 = NULL;
4713                 u16 family_sa;
4714                 unsigned short snum;
4715                 u32 sid, node_perm;
4716
4717                 /*
4718                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4719                  * that validates multiple binding addresses. Because of this
4720                  * need to check address->sa_family as it is possible to have
4721                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4722                  */
4723                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4724                         return -EINVAL;
4725                 family_sa = address->sa_family;
4726                 switch (family_sa) {
4727                 case AF_UNSPEC:
4728                 case AF_INET:
4729                         if (addrlen < sizeof(struct sockaddr_in))
4730                                 return -EINVAL;
4731                         addr4 = (struct sockaddr_in *)address;
4732                         if (family_sa == AF_UNSPEC) {
4733                                 if (family == PF_INET6) {
4734                                         /* Length check from inet6_bind_sk() */
4735                                         if (addrlen < SIN6_LEN_RFC2133)
4736                                                 return -EINVAL;
4737                                         /* Family check from __inet6_bind() */
4738                                         goto err_af;
4739                                 }
4740                                 /* see __inet_bind(), we only want to allow
4741                                  * AF_UNSPEC if the address is INADDR_ANY
4742                                  */
4743                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4744                                         goto err_af;
4745                                 family_sa = AF_INET;
4746                         }
4747                         snum = ntohs(addr4->sin_port);
4748                         addrp = (char *)&addr4->sin_addr.s_addr;
4749                         break;
4750                 case AF_INET6:
4751                         if (addrlen < SIN6_LEN_RFC2133)
4752                                 return -EINVAL;
4753                         addr6 = (struct sockaddr_in6 *)address;
4754                         snum = ntohs(addr6->sin6_port);
4755                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4756                         break;
4757                 default:
4758                         goto err_af;
4759                 }
4760
4761                 ad.type = LSM_AUDIT_DATA_NET;
4762                 ad.u.net = &net;
4763                 ad.u.net->sport = htons(snum);
4764                 ad.u.net->family = family_sa;
4765
4766                 if (snum) {
4767                         int low, high;
4768
4769                         inet_get_local_port_range(sock_net(sk), &low, &high);
4770
4771                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4772                             snum < low || snum > high) {
4773                                 err = sel_netport_sid(sk->sk_protocol,
4774                                                       snum, &sid);
4775                                 if (err)
4776                                         goto out;
4777                                 err = avc_has_perm(sksec->sid, sid,
4778                                                    sksec->sclass,
4779                                                    SOCKET__NAME_BIND, &ad);
4780                                 if (err)
4781                                         goto out;
4782                         }
4783                 }
4784
4785                 switch (sksec->sclass) {
4786                 case SECCLASS_TCP_SOCKET:
4787                         node_perm = TCP_SOCKET__NODE_BIND;
4788                         break;
4789
4790                 case SECCLASS_UDP_SOCKET:
4791                         node_perm = UDP_SOCKET__NODE_BIND;
4792                         break;
4793
4794                 case SECCLASS_DCCP_SOCKET:
4795                         node_perm = DCCP_SOCKET__NODE_BIND;
4796                         break;
4797
4798                 case SECCLASS_SCTP_SOCKET:
4799                         node_perm = SCTP_SOCKET__NODE_BIND;
4800                         break;
4801
4802                 default:
4803                         node_perm = RAWIP_SOCKET__NODE_BIND;
4804                         break;
4805                 }
4806
4807                 err = sel_netnode_sid(addrp, family_sa, &sid);
4808                 if (err)
4809                         goto out;
4810
4811                 if (family_sa == AF_INET)
4812                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4813                 else
4814                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4815
4816                 err = avc_has_perm(sksec->sid, sid,
4817                                    sksec->sclass, node_perm, &ad);
4818                 if (err)
4819                         goto out;
4820         }
4821 out:
4822         return err;
4823 err_af:
4824         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4825         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4826                 return -EINVAL;
4827         return -EAFNOSUPPORT;
4828 }
4829
4830 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4831  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4832  */
4833 static int selinux_socket_connect_helper(struct socket *sock,
4834                                          struct sockaddr *address, int addrlen)
4835 {
4836         struct sock *sk = sock->sk;
4837         struct sk_security_struct *sksec = sk->sk_security;
4838         int err;
4839
4840         err = sock_has_perm(sk, SOCKET__CONNECT);
4841         if (err)
4842                 return err;
4843         if (addrlen < offsetofend(struct sockaddr, sa_family))
4844                 return -EINVAL;
4845
4846         /* connect(AF_UNSPEC) has special handling, as it is a documented
4847          * way to disconnect the socket
4848          */
4849         if (address->sa_family == AF_UNSPEC)
4850                 return 0;
4851
4852         /*
4853          * If a TCP, DCCP or SCTP socket, check name_connect permission
4854          * for the port.
4855          */
4856         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4857             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4858             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4859                 struct common_audit_data ad;
4860                 struct lsm_network_audit net = {0,};
4861                 struct sockaddr_in *addr4 = NULL;
4862                 struct sockaddr_in6 *addr6 = NULL;
4863                 unsigned short snum;
4864                 u32 sid, perm;
4865
4866                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4867                  * that validates multiple connect addresses. Because of this
4868                  * need to check address->sa_family as it is possible to have
4869                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4870                  */
4871                 switch (address->sa_family) {
4872                 case AF_INET:
4873                         addr4 = (struct sockaddr_in *)address;
4874                         if (addrlen < sizeof(struct sockaddr_in))
4875                                 return -EINVAL;
4876                         snum = ntohs(addr4->sin_port);
4877                         break;
4878                 case AF_INET6:
4879                         addr6 = (struct sockaddr_in6 *)address;
4880                         if (addrlen < SIN6_LEN_RFC2133)
4881                                 return -EINVAL;
4882                         snum = ntohs(addr6->sin6_port);
4883                         break;
4884                 default:
4885                         /* Note that SCTP services expect -EINVAL, whereas
4886                          * others expect -EAFNOSUPPORT.
4887                          */
4888                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4889                                 return -EINVAL;
4890                         else
4891                                 return -EAFNOSUPPORT;
4892                 }
4893
4894                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4895                 if (err)
4896                         return err;
4897
4898                 switch (sksec->sclass) {
4899                 case SECCLASS_TCP_SOCKET:
4900                         perm = TCP_SOCKET__NAME_CONNECT;
4901                         break;
4902                 case SECCLASS_DCCP_SOCKET:
4903                         perm = DCCP_SOCKET__NAME_CONNECT;
4904                         break;
4905                 case SECCLASS_SCTP_SOCKET:
4906                         perm = SCTP_SOCKET__NAME_CONNECT;
4907                         break;
4908                 }
4909
4910                 ad.type = LSM_AUDIT_DATA_NET;
4911                 ad.u.net = &net;
4912                 ad.u.net->dport = htons(snum);
4913                 ad.u.net->family = address->sa_family;
4914                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4915                 if (err)
4916                         return err;
4917         }
4918
4919         return 0;
4920 }
4921
4922 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4923 static int selinux_socket_connect(struct socket *sock,
4924                                   struct sockaddr *address, int addrlen)
4925 {
4926         int err;
4927         struct sock *sk = sock->sk;
4928
4929         err = selinux_socket_connect_helper(sock, address, addrlen);
4930         if (err)
4931                 return err;
4932
4933         return selinux_netlbl_socket_connect(sk, address);
4934 }
4935
4936 static int selinux_socket_listen(struct socket *sock, int backlog)
4937 {
4938         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4939 }
4940
4941 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4942 {
4943         int err;
4944         struct inode_security_struct *isec;
4945         struct inode_security_struct *newisec;
4946         u16 sclass;
4947         u32 sid;
4948
4949         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4950         if (err)
4951                 return err;
4952
4953         isec = inode_security_novalidate(SOCK_INODE(sock));
4954         spin_lock(&isec->lock);
4955         sclass = isec->sclass;
4956         sid = isec->sid;
4957         spin_unlock(&isec->lock);
4958
4959         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4960         newisec->sclass = sclass;
4961         newisec->sid = sid;
4962         newisec->initialized = LABEL_INITIALIZED;
4963
4964         return 0;
4965 }
4966
4967 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4968                                   int size)
4969 {
4970         return sock_has_perm(sock->sk, SOCKET__WRITE);
4971 }
4972
4973 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4974                                   int size, int flags)
4975 {
4976         return sock_has_perm(sock->sk, SOCKET__READ);
4977 }
4978
4979 static int selinux_socket_getsockname(struct socket *sock)
4980 {
4981         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4982 }
4983
4984 static int selinux_socket_getpeername(struct socket *sock)
4985 {
4986         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4987 }
4988
4989 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4990 {
4991         int err;
4992
4993         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4994         if (err)
4995                 return err;
4996
4997         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4998 }
4999
5000 static int selinux_socket_getsockopt(struct socket *sock, int level,
5001                                      int optname)
5002 {
5003         return sock_has_perm(sock->sk, SOCKET__GETOPT);
5004 }
5005
5006 static int selinux_socket_shutdown(struct socket *sock, int how)
5007 {
5008         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5009 }
5010
5011 static int selinux_socket_unix_stream_connect(struct sock *sock,
5012                                               struct sock *other,
5013                                               struct sock *newsk)
5014 {
5015         struct sk_security_struct *sksec_sock = sock->sk_security;
5016         struct sk_security_struct *sksec_other = other->sk_security;
5017         struct sk_security_struct *sksec_new = newsk->sk_security;
5018         struct common_audit_data ad;
5019         struct lsm_network_audit net;
5020         int err;
5021
5022         ad_net_init_from_sk(&ad, &net, other);
5023
5024         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5025                            sksec_other->sclass,
5026                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5027         if (err)
5028                 return err;
5029
5030         /* server child socket */
5031         sksec_new->peer_sid = sksec_sock->sid;
5032         err = security_sid_mls_copy(sksec_other->sid,
5033                                     sksec_sock->sid, &sksec_new->sid);
5034         if (err)
5035                 return err;
5036
5037         /* connecting socket */
5038         sksec_sock->peer_sid = sksec_new->sid;
5039
5040         return 0;
5041 }
5042
5043 static int selinux_socket_unix_may_send(struct socket *sock,
5044                                         struct socket *other)
5045 {
5046         struct sk_security_struct *ssec = sock->sk->sk_security;
5047         struct sk_security_struct *osec = other->sk->sk_security;
5048         struct common_audit_data ad;
5049         struct lsm_network_audit net;
5050
5051         ad_net_init_from_sk(&ad, &net, other->sk);
5052
5053         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5054                             &ad);
5055 }
5056
5057 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5058                                     char *addrp, u16 family, u32 peer_sid,
5059                                     struct common_audit_data *ad)
5060 {
5061         int err;
5062         u32 if_sid;
5063         u32 node_sid;
5064
5065         err = sel_netif_sid(ns, ifindex, &if_sid);
5066         if (err)
5067                 return err;
5068         err = avc_has_perm(peer_sid, if_sid,
5069                            SECCLASS_NETIF, NETIF__INGRESS, ad);
5070         if (err)
5071                 return err;
5072
5073         err = sel_netnode_sid(addrp, family, &node_sid);
5074         if (err)
5075                 return err;
5076         return avc_has_perm(peer_sid, node_sid,
5077                             SECCLASS_NODE, NODE__RECVFROM, ad);
5078 }
5079
5080 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5081                                        u16 family)
5082 {
5083         int err = 0;
5084         struct sk_security_struct *sksec = sk->sk_security;
5085         u32 sk_sid = sksec->sid;
5086         struct common_audit_data ad;
5087         struct lsm_network_audit net;
5088         char *addrp;
5089
5090         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5091         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5092         if (err)
5093                 return err;
5094
5095         if (selinux_secmark_enabled()) {
5096                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5097                                    PACKET__RECV, &ad);
5098                 if (err)
5099                         return err;
5100         }
5101
5102         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5103         if (err)
5104                 return err;
5105         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5106
5107         return err;
5108 }
5109
5110 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5111 {
5112         int err, peerlbl_active, secmark_active;
5113         struct sk_security_struct *sksec = sk->sk_security;
5114         u16 family = sk->sk_family;
5115         u32 sk_sid = sksec->sid;
5116         struct common_audit_data ad;
5117         struct lsm_network_audit net;
5118         char *addrp;
5119
5120         if (family != PF_INET && family != PF_INET6)
5121                 return 0;
5122
5123         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5124         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5125                 family = PF_INET;
5126
5127         /* If any sort of compatibility mode is enabled then handoff processing
5128          * to the selinux_sock_rcv_skb_compat() function to deal with the
5129          * special handling.  We do this in an attempt to keep this function
5130          * as fast and as clean as possible. */
5131         if (!selinux_policycap_netpeer())
5132                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5133
5134         secmark_active = selinux_secmark_enabled();
5135         peerlbl_active = selinux_peerlbl_enabled();
5136         if (!secmark_active && !peerlbl_active)
5137                 return 0;
5138
5139         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5140         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5141         if (err)
5142                 return err;
5143
5144         if (peerlbl_active) {
5145                 u32 peer_sid;
5146
5147                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5148                 if (err)
5149                         return err;
5150                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5151                                                addrp, family, peer_sid, &ad);
5152                 if (err) {
5153                         selinux_netlbl_err(skb, family, err, 0);
5154                         return err;
5155                 }
5156                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5157                                    PEER__RECV, &ad);
5158                 if (err) {
5159                         selinux_netlbl_err(skb, family, err, 0);
5160                         return err;
5161                 }
5162         }
5163
5164         if (secmark_active) {
5165                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5166                                    PACKET__RECV, &ad);
5167                 if (err)
5168                         return err;
5169         }
5170
5171         return err;
5172 }
5173
5174 static int selinux_socket_getpeersec_stream(struct socket *sock,
5175                                             sockptr_t optval, sockptr_t optlen,
5176                                             unsigned int len)
5177 {
5178         int err = 0;
5179         char *scontext = NULL;
5180         u32 scontext_len;
5181         struct sk_security_struct *sksec = sock->sk->sk_security;
5182         u32 peer_sid = SECSID_NULL;
5183
5184         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5185             sksec->sclass == SECCLASS_TCP_SOCKET ||
5186             sksec->sclass == SECCLASS_SCTP_SOCKET)
5187                 peer_sid = sksec->peer_sid;
5188         if (peer_sid == SECSID_NULL)
5189                 return -ENOPROTOOPT;
5190
5191         err = security_sid_to_context(peer_sid, &scontext,
5192                                       &scontext_len);
5193         if (err)
5194                 return err;
5195         if (scontext_len > len) {
5196                 err = -ERANGE;
5197                 goto out_len;
5198         }
5199
5200         if (copy_to_sockptr(optval, scontext, scontext_len))
5201                 err = -EFAULT;
5202 out_len:
5203         if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5204                 err = -EFAULT;
5205         kfree(scontext);
5206         return err;
5207 }
5208
5209 static int selinux_socket_getpeersec_dgram(struct socket *sock,
5210                                            struct sk_buff *skb, u32 *secid)
5211 {
5212         u32 peer_secid = SECSID_NULL;
5213         u16 family;
5214
5215         if (skb && skb->protocol == htons(ETH_P_IP))
5216                 family = PF_INET;
5217         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5218                 family = PF_INET6;
5219         else if (sock)
5220                 family = sock->sk->sk_family;
5221         else {
5222                 *secid = SECSID_NULL;
5223                 return -EINVAL;
5224         }
5225
5226         if (sock && family == PF_UNIX) {
5227                 struct inode_security_struct *isec;
5228                 isec = inode_security_novalidate(SOCK_INODE(sock));
5229                 peer_secid = isec->sid;
5230         } else if (skb)
5231                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5232
5233         *secid = peer_secid;
5234         if (peer_secid == SECSID_NULL)
5235                 return -ENOPROTOOPT;
5236         return 0;
5237 }
5238
5239 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5240 {
5241         struct sk_security_struct *sksec;
5242
5243         sksec = kzalloc(sizeof(*sksec), priority);
5244         if (!sksec)
5245                 return -ENOMEM;
5246
5247         sksec->peer_sid = SECINITSID_UNLABELED;
5248         sksec->sid = SECINITSID_UNLABELED;
5249         sksec->sclass = SECCLASS_SOCKET;
5250         selinux_netlbl_sk_security_reset(sksec);
5251         sk->sk_security = sksec;
5252
5253         return 0;
5254 }
5255
5256 static void selinux_sk_free_security(struct sock *sk)
5257 {
5258         struct sk_security_struct *sksec = sk->sk_security;
5259
5260         sk->sk_security = NULL;
5261         selinux_netlbl_sk_security_free(sksec);
5262         kfree(sksec);
5263 }
5264
5265 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5266 {
5267         struct sk_security_struct *sksec = sk->sk_security;
5268         struct sk_security_struct *newsksec = newsk->sk_security;
5269
5270         newsksec->sid = sksec->sid;
5271         newsksec->peer_sid = sksec->peer_sid;
5272         newsksec->sclass = sksec->sclass;
5273
5274         selinux_netlbl_sk_security_reset(newsksec);
5275 }
5276
5277 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5278 {
5279         if (!sk)
5280                 *secid = SECINITSID_ANY_SOCKET;
5281         else {
5282                 const struct sk_security_struct *sksec = sk->sk_security;
5283
5284                 *secid = sksec->sid;
5285         }
5286 }
5287
5288 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5289 {
5290         struct inode_security_struct *isec =
5291                 inode_security_novalidate(SOCK_INODE(parent));
5292         struct sk_security_struct *sksec = sk->sk_security;
5293
5294         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5295             sk->sk_family == PF_UNIX)
5296                 isec->sid = sksec->sid;
5297         sksec->sclass = isec->sclass;
5298 }
5299
5300 /*
5301  * Determines peer_secid for the asoc and updates socket's peer label
5302  * if it's the first association on the socket.
5303  */
5304 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5305                                           struct sk_buff *skb)
5306 {
5307         struct sock *sk = asoc->base.sk;
5308         u16 family = sk->sk_family;
5309         struct sk_security_struct *sksec = sk->sk_security;
5310         struct common_audit_data ad;
5311         struct lsm_network_audit net;
5312         int err;
5313
5314         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5315         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5316                 family = PF_INET;
5317
5318         if (selinux_peerlbl_enabled()) {
5319                 asoc->peer_secid = SECSID_NULL;
5320
5321                 /* This will return peer_sid = SECSID_NULL if there are
5322                  * no peer labels, see security_net_peersid_resolve().
5323                  */
5324                 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5325                 if (err)
5326                         return err;
5327
5328                 if (asoc->peer_secid == SECSID_NULL)
5329                         asoc->peer_secid = SECINITSID_UNLABELED;
5330         } else {
5331                 asoc->peer_secid = SECINITSID_UNLABELED;
5332         }
5333
5334         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5335                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5336
5337                 /* Here as first association on socket. As the peer SID
5338                  * was allowed by peer recv (and the netif/node checks),
5339                  * then it is approved by policy and used as the primary
5340                  * peer SID for getpeercon(3).
5341                  */
5342                 sksec->peer_sid = asoc->peer_secid;
5343         } else if (sksec->peer_sid != asoc->peer_secid) {
5344                 /* Other association peer SIDs are checked to enforce
5345                  * consistency among the peer SIDs.
5346                  */
5347                 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5348                 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5349                                    sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5350                                    &ad);
5351                 if (err)
5352                         return err;
5353         }
5354         return 0;
5355 }
5356
5357 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5358  * happens on an incoming connect(2), sctp_connectx(3) or
5359  * sctp_sendmsg(3) (with no association already present).
5360  */
5361 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5362                                       struct sk_buff *skb)
5363 {
5364         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5365         u32 conn_sid;
5366         int err;
5367
5368         if (!selinux_policycap_extsockclass())
5369                 return 0;
5370
5371         err = selinux_sctp_process_new_assoc(asoc, skb);
5372         if (err)
5373                 return err;
5374
5375         /* Compute the MLS component for the connection and store
5376          * the information in asoc. This will be used by SCTP TCP type
5377          * sockets and peeled off connections as they cause a new
5378          * socket to be generated. selinux_sctp_sk_clone() will then
5379          * plug this into the new socket.
5380          */
5381         err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5382         if (err)
5383                 return err;
5384
5385         asoc->secid = conn_sid;
5386
5387         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5388         return selinux_netlbl_sctp_assoc_request(asoc, skb);
5389 }
5390
5391 /* Called when SCTP receives a COOKIE ACK chunk as the final
5392  * response to an association request (initited by us).
5393  */
5394 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5395                                           struct sk_buff *skb)
5396 {
5397         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5398
5399         if (!selinux_policycap_extsockclass())
5400                 return 0;
5401
5402         /* Inherit secid from the parent socket - this will be picked up
5403          * by selinux_sctp_sk_clone() if the association gets peeled off
5404          * into a new socket.
5405          */
5406         asoc->secid = sksec->sid;
5407
5408         return selinux_sctp_process_new_assoc(asoc, skb);
5409 }
5410
5411 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5412  * based on their @optname.
5413  */
5414 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5415                                      struct sockaddr *address,
5416                                      int addrlen)
5417 {
5418         int len, err = 0, walk_size = 0;
5419         void *addr_buf;
5420         struct sockaddr *addr;
5421         struct socket *sock;
5422
5423         if (!selinux_policycap_extsockclass())
5424                 return 0;
5425
5426         /* Process one or more addresses that may be IPv4 or IPv6 */
5427         sock = sk->sk_socket;
5428         addr_buf = address;
5429
5430         while (walk_size < addrlen) {
5431                 if (walk_size + sizeof(sa_family_t) > addrlen)
5432                         return -EINVAL;
5433
5434                 addr = addr_buf;
5435                 switch (addr->sa_family) {
5436                 case AF_UNSPEC:
5437                 case AF_INET:
5438                         len = sizeof(struct sockaddr_in);
5439                         break;
5440                 case AF_INET6:
5441                         len = sizeof(struct sockaddr_in6);
5442                         break;
5443                 default:
5444                         return -EINVAL;
5445                 }
5446
5447                 if (walk_size + len > addrlen)
5448                         return -EINVAL;
5449
5450                 err = -EINVAL;
5451                 switch (optname) {
5452                 /* Bind checks */
5453                 case SCTP_PRIMARY_ADDR:
5454                 case SCTP_SET_PEER_PRIMARY_ADDR:
5455                 case SCTP_SOCKOPT_BINDX_ADD:
5456                         err = selinux_socket_bind(sock, addr, len);
5457                         break;
5458                 /* Connect checks */
5459                 case SCTP_SOCKOPT_CONNECTX:
5460                 case SCTP_PARAM_SET_PRIMARY:
5461                 case SCTP_PARAM_ADD_IP:
5462                 case SCTP_SENDMSG_CONNECT:
5463                         err = selinux_socket_connect_helper(sock, addr, len);
5464                         if (err)
5465                                 return err;
5466
5467                         /* As selinux_sctp_bind_connect() is called by the
5468                          * SCTP protocol layer, the socket is already locked,
5469                          * therefore selinux_netlbl_socket_connect_locked()
5470                          * is called here. The situations handled are:
5471                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5472                          * whenever a new IP address is added or when a new
5473                          * primary address is selected.
5474                          * Note that an SCTP connect(2) call happens before
5475                          * the SCTP protocol layer and is handled via
5476                          * selinux_socket_connect().
5477                          */
5478                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5479                         break;
5480                 }
5481
5482                 if (err)
5483                         return err;
5484
5485                 addr_buf += len;
5486                 walk_size += len;
5487         }
5488
5489         return 0;
5490 }
5491
5492 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5493 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5494                                   struct sock *newsk)
5495 {
5496         struct sk_security_struct *sksec = sk->sk_security;
5497         struct sk_security_struct *newsksec = newsk->sk_security;
5498
5499         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5500          * the non-sctp clone version.
5501          */
5502         if (!selinux_policycap_extsockclass())
5503                 return selinux_sk_clone_security(sk, newsk);
5504
5505         newsksec->sid = asoc->secid;
5506         newsksec->peer_sid = asoc->peer_secid;
5507         newsksec->sclass = sksec->sclass;
5508         selinux_netlbl_sctp_sk_clone(sk, newsk);
5509 }
5510
5511 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5512 {
5513         struct sk_security_struct *ssksec = ssk->sk_security;
5514         struct sk_security_struct *sksec = sk->sk_security;
5515
5516         ssksec->sclass = sksec->sclass;
5517         ssksec->sid = sksec->sid;
5518
5519         /* replace the existing subflow label deleting the existing one
5520          * and re-recreating a new label using the updated context
5521          */
5522         selinux_netlbl_sk_security_free(ssksec);
5523         return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5524 }
5525
5526 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5527                                      struct request_sock *req)
5528 {
5529         struct sk_security_struct *sksec = sk->sk_security;
5530         int err;
5531         u16 family = req->rsk_ops->family;
5532         u32 connsid;
5533         u32 peersid;
5534
5535         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5536         if (err)
5537                 return err;
5538         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5539         if (err)
5540                 return err;
5541         req->secid = connsid;
5542         req->peer_secid = peersid;
5543
5544         return selinux_netlbl_inet_conn_request(req, family);
5545 }
5546
5547 static void selinux_inet_csk_clone(struct sock *newsk,
5548                                    const struct request_sock *req)
5549 {
5550         struct sk_security_struct *newsksec = newsk->sk_security;
5551
5552         newsksec->sid = req->secid;
5553         newsksec->peer_sid = req->peer_secid;
5554         /* NOTE: Ideally, we should also get the isec->sid for the
5555            new socket in sync, but we don't have the isec available yet.
5556            So we will wait until sock_graft to do it, by which
5557            time it will have been created and available. */
5558
5559         /* We don't need to take any sort of lock here as we are the only
5560          * thread with access to newsksec */
5561         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5562 }
5563
5564 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5565 {
5566         u16 family = sk->sk_family;
5567         struct sk_security_struct *sksec = sk->sk_security;
5568
5569         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5570         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5571                 family = PF_INET;
5572
5573         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5574 }
5575
5576 static int selinux_secmark_relabel_packet(u32 sid)
5577 {
5578         return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5579                             NULL);
5580 }
5581
5582 static void selinux_secmark_refcount_inc(void)
5583 {
5584         atomic_inc(&selinux_secmark_refcount);
5585 }
5586
5587 static void selinux_secmark_refcount_dec(void)
5588 {
5589         atomic_dec(&selinux_secmark_refcount);
5590 }
5591
5592 static void selinux_req_classify_flow(const struct request_sock *req,
5593                                       struct flowi_common *flic)
5594 {
5595         flic->flowic_secid = req->secid;
5596 }
5597
5598 static int selinux_tun_dev_alloc_security(void **security)
5599 {
5600         struct tun_security_struct *tunsec;
5601
5602         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5603         if (!tunsec)
5604                 return -ENOMEM;
5605         tunsec->sid = current_sid();
5606
5607         *security = tunsec;
5608         return 0;
5609 }
5610
5611 static void selinux_tun_dev_free_security(void *security)
5612 {
5613         kfree(security);
5614 }
5615
5616 static int selinux_tun_dev_create(void)
5617 {
5618         u32 sid = current_sid();
5619
5620         /* we aren't taking into account the "sockcreate" SID since the socket
5621          * that is being created here is not a socket in the traditional sense,
5622          * instead it is a private sock, accessible only to the kernel, and
5623          * representing a wide range of network traffic spanning multiple
5624          * connections unlike traditional sockets - check the TUN driver to
5625          * get a better understanding of why this socket is special */
5626
5627         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5628                             NULL);
5629 }
5630
5631 static int selinux_tun_dev_attach_queue(void *security)
5632 {
5633         struct tun_security_struct *tunsec = security;
5634
5635         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5636                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5637 }
5638
5639 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5640 {
5641         struct tun_security_struct *tunsec = security;
5642         struct sk_security_struct *sksec = sk->sk_security;
5643
5644         /* we don't currently perform any NetLabel based labeling here and it
5645          * isn't clear that we would want to do so anyway; while we could apply
5646          * labeling without the support of the TUN user the resulting labeled
5647          * traffic from the other end of the connection would almost certainly
5648          * cause confusion to the TUN user that had no idea network labeling
5649          * protocols were being used */
5650
5651         sksec->sid = tunsec->sid;
5652         sksec->sclass = SECCLASS_TUN_SOCKET;
5653
5654         return 0;
5655 }
5656
5657 static int selinux_tun_dev_open(void *security)
5658 {
5659         struct tun_security_struct *tunsec = security;
5660         u32 sid = current_sid();
5661         int err;
5662
5663         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5664                            TUN_SOCKET__RELABELFROM, NULL);
5665         if (err)
5666                 return err;
5667         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5668                            TUN_SOCKET__RELABELTO, NULL);
5669         if (err)
5670                 return err;
5671         tunsec->sid = sid;
5672
5673         return 0;
5674 }
5675
5676 #ifdef CONFIG_NETFILTER
5677
5678 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5679                                        const struct nf_hook_state *state)
5680 {
5681         int ifindex;
5682         u16 family;
5683         char *addrp;
5684         u32 peer_sid;
5685         struct common_audit_data ad;
5686         struct lsm_network_audit net;
5687         int secmark_active, peerlbl_active;
5688
5689         if (!selinux_policycap_netpeer())
5690                 return NF_ACCEPT;
5691
5692         secmark_active = selinux_secmark_enabled();
5693         peerlbl_active = selinux_peerlbl_enabled();
5694         if (!secmark_active && !peerlbl_active)
5695                 return NF_ACCEPT;
5696
5697         family = state->pf;
5698         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5699                 return NF_DROP;
5700
5701         ifindex = state->in->ifindex;
5702         ad_net_init_from_iif(&ad, &net, ifindex, family);
5703         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5704                 return NF_DROP;
5705
5706         if (peerlbl_active) {
5707                 int err;
5708
5709                 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5710                                                addrp, family, peer_sid, &ad);
5711                 if (err) {
5712                         selinux_netlbl_err(skb, family, err, 1);
5713                         return NF_DROP;
5714                 }
5715         }
5716
5717         if (secmark_active)
5718                 if (avc_has_perm(peer_sid, skb->secmark,
5719                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5720                         return NF_DROP;
5721
5722         if (netlbl_enabled())
5723                 /* we do this in the FORWARD path and not the POST_ROUTING
5724                  * path because we want to make sure we apply the necessary
5725                  * labeling before IPsec is applied so we can leverage AH
5726                  * protection */
5727                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5728                         return NF_DROP;
5729
5730         return NF_ACCEPT;
5731 }
5732
5733 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5734                                       const struct nf_hook_state *state)
5735 {
5736         struct sock *sk;
5737         u32 sid;
5738
5739         if (!netlbl_enabled())
5740                 return NF_ACCEPT;
5741
5742         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5743          * because we want to make sure we apply the necessary labeling
5744          * before IPsec is applied so we can leverage AH protection */
5745         sk = skb->sk;
5746         if (sk) {
5747                 struct sk_security_struct *sksec;
5748
5749                 if (sk_listener(sk))
5750                         /* if the socket is the listening state then this
5751                          * packet is a SYN-ACK packet which means it needs to
5752                          * be labeled based on the connection/request_sock and
5753                          * not the parent socket.  unfortunately, we can't
5754                          * lookup the request_sock yet as it isn't queued on
5755                          * the parent socket until after the SYN-ACK is sent.
5756                          * the "solution" is to simply pass the packet as-is
5757                          * as any IP option based labeling should be copied
5758                          * from the initial connection request (in the IP
5759                          * layer).  it is far from ideal, but until we get a
5760                          * security label in the packet itself this is the
5761                          * best we can do. */
5762                         return NF_ACCEPT;
5763
5764                 /* standard practice, label using the parent socket */
5765                 sksec = sk->sk_security;
5766                 sid = sksec->sid;
5767         } else
5768                 sid = SECINITSID_KERNEL;
5769         if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5770                 return NF_DROP;
5771
5772         return NF_ACCEPT;
5773 }
5774
5775
5776 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5777                                         const struct nf_hook_state *state)
5778 {
5779         struct sock *sk;
5780         struct sk_security_struct *sksec;
5781         struct common_audit_data ad;
5782         struct lsm_network_audit net;
5783         u8 proto = 0;
5784
5785         sk = skb_to_full_sk(skb);
5786         if (sk == NULL)
5787                 return NF_ACCEPT;
5788         sksec = sk->sk_security;
5789
5790         ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5791         if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5792                 return NF_DROP;
5793
5794         if (selinux_secmark_enabled())
5795                 if (avc_has_perm(sksec->sid, skb->secmark,
5796                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5797                         return NF_DROP_ERR(-ECONNREFUSED);
5798
5799         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5800                 return NF_DROP_ERR(-ECONNREFUSED);
5801
5802         return NF_ACCEPT;
5803 }
5804
5805 static unsigned int selinux_ip_postroute(void *priv,
5806                                          struct sk_buff *skb,
5807                                          const struct nf_hook_state *state)
5808 {
5809         u16 family;
5810         u32 secmark_perm;
5811         u32 peer_sid;
5812         int ifindex;
5813         struct sock *sk;
5814         struct common_audit_data ad;
5815         struct lsm_network_audit net;
5816         char *addrp;
5817         int secmark_active, peerlbl_active;
5818
5819         /* If any sort of compatibility mode is enabled then handoff processing
5820          * to the selinux_ip_postroute_compat() function to deal with the
5821          * special handling.  We do this in an attempt to keep this function
5822          * as fast and as clean as possible. */
5823         if (!selinux_policycap_netpeer())
5824                 return selinux_ip_postroute_compat(skb, state);
5825
5826         secmark_active = selinux_secmark_enabled();
5827         peerlbl_active = selinux_peerlbl_enabled();
5828         if (!secmark_active && !peerlbl_active)
5829                 return NF_ACCEPT;
5830
5831         sk = skb_to_full_sk(skb);
5832
5833 #ifdef CONFIG_XFRM
5834         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5835          * packet transformation so allow the packet to pass without any checks
5836          * since we'll have another chance to perform access control checks
5837          * when the packet is on it's final way out.
5838          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5839          *       is NULL, in this case go ahead and apply access control.
5840          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5841          *       TCP listening state we cannot wait until the XFRM processing
5842          *       is done as we will miss out on the SA label if we do;
5843          *       unfortunately, this means more work, but it is only once per
5844          *       connection. */
5845         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5846             !(sk && sk_listener(sk)))
5847                 return NF_ACCEPT;
5848 #endif
5849
5850         family = state->pf;
5851         if (sk == NULL) {
5852                 /* Without an associated socket the packet is either coming
5853                  * from the kernel or it is being forwarded; check the packet
5854                  * to determine which and if the packet is being forwarded
5855                  * query the packet directly to determine the security label. */
5856                 if (skb->skb_iif) {
5857                         secmark_perm = PACKET__FORWARD_OUT;
5858                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5859                                 return NF_DROP;
5860                 } else {
5861                         secmark_perm = PACKET__SEND;
5862                         peer_sid = SECINITSID_KERNEL;
5863                 }
5864         } else if (sk_listener(sk)) {
5865                 /* Locally generated packet but the associated socket is in the
5866                  * listening state which means this is a SYN-ACK packet.  In
5867                  * this particular case the correct security label is assigned
5868                  * to the connection/request_sock but unfortunately we can't
5869                  * query the request_sock as it isn't queued on the parent
5870                  * socket until after the SYN-ACK packet is sent; the only
5871                  * viable choice is to regenerate the label like we do in
5872                  * selinux_inet_conn_request().  See also selinux_ip_output()
5873                  * for similar problems. */
5874                 u32 skb_sid;
5875                 struct sk_security_struct *sksec;
5876
5877                 sksec = sk->sk_security;
5878                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5879                         return NF_DROP;
5880                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5881                  * and the packet has been through at least one XFRM
5882                  * transformation then we must be dealing with the "final"
5883                  * form of labeled IPsec packet; since we've already applied
5884                  * all of our access controls on this packet we can safely
5885                  * pass the packet. */
5886                 if (skb_sid == SECSID_NULL) {
5887                         switch (family) {
5888                         case PF_INET:
5889                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5890                                         return NF_ACCEPT;
5891                                 break;
5892                         case PF_INET6:
5893                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5894                                         return NF_ACCEPT;
5895                                 break;
5896                         default:
5897                                 return NF_DROP_ERR(-ECONNREFUSED);
5898                         }
5899                 }
5900                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5901                         return NF_DROP;
5902                 secmark_perm = PACKET__SEND;
5903         } else {
5904                 /* Locally generated packet, fetch the security label from the
5905                  * associated socket. */
5906                 struct sk_security_struct *sksec = sk->sk_security;
5907                 peer_sid = sksec->sid;
5908                 secmark_perm = PACKET__SEND;
5909         }
5910
5911         ifindex = state->out->ifindex;
5912         ad_net_init_from_iif(&ad, &net, ifindex, family);
5913         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5914                 return NF_DROP;
5915
5916         if (secmark_active)
5917                 if (avc_has_perm(peer_sid, skb->secmark,
5918                                  SECCLASS_PACKET, secmark_perm, &ad))
5919                         return NF_DROP_ERR(-ECONNREFUSED);
5920
5921         if (peerlbl_active) {
5922                 u32 if_sid;
5923                 u32 node_sid;
5924
5925                 if (sel_netif_sid(state->net, ifindex, &if_sid))
5926                         return NF_DROP;
5927                 if (avc_has_perm(peer_sid, if_sid,
5928                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5929                         return NF_DROP_ERR(-ECONNREFUSED);
5930
5931                 if (sel_netnode_sid(addrp, family, &node_sid))
5932                         return NF_DROP;
5933                 if (avc_has_perm(peer_sid, node_sid,
5934                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5935                         return NF_DROP_ERR(-ECONNREFUSED);
5936         }
5937
5938         return NF_ACCEPT;
5939 }
5940 #endif  /* CONFIG_NETFILTER */
5941
5942 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5943 {
5944         int rc = 0;
5945         unsigned int msg_len;
5946         unsigned int data_len = skb->len;
5947         unsigned char *data = skb->data;
5948         struct nlmsghdr *nlh;
5949         struct sk_security_struct *sksec = sk->sk_security;
5950         u16 sclass = sksec->sclass;
5951         u32 perm;
5952
5953         while (data_len >= nlmsg_total_size(0)) {
5954                 nlh = (struct nlmsghdr *)data;
5955
5956                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5957                  *       users which means we can't reject skb's with bogus
5958                  *       length fields; our solution is to follow what
5959                  *       netlink_rcv_skb() does and simply skip processing at
5960                  *       messages with length fields that are clearly junk
5961                  */
5962                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5963                         return 0;
5964
5965                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5966                 if (rc == 0) {
5967                         rc = sock_has_perm(sk, perm);
5968                         if (rc)
5969                                 return rc;
5970                 } else if (rc == -EINVAL) {
5971                         /* -EINVAL is a missing msg/perm mapping */
5972                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5973                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5974                                 " pid=%d comm=%s\n",
5975                                 sk->sk_protocol, nlh->nlmsg_type,
5976                                 secclass_map[sclass - 1].name,
5977                                 task_pid_nr(current), current->comm);
5978                         if (enforcing_enabled() &&
5979                             !security_get_allow_unknown())
5980                                 return rc;
5981                         rc = 0;
5982                 } else if (rc == -ENOENT) {
5983                         /* -ENOENT is a missing socket/class mapping, ignore */
5984                         rc = 0;
5985                 } else {
5986                         return rc;
5987                 }
5988
5989                 /* move to the next message after applying netlink padding */
5990                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5991                 if (msg_len >= data_len)
5992                         return 0;
5993                 data_len -= msg_len;
5994                 data += msg_len;
5995         }
5996
5997         return rc;
5998 }
5999
6000 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6001 {
6002         isec->sclass = sclass;
6003         isec->sid = current_sid();
6004 }
6005
6006 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6007                         u32 perms)
6008 {
6009         struct ipc_security_struct *isec;
6010         struct common_audit_data ad;
6011         u32 sid = current_sid();
6012
6013         isec = selinux_ipc(ipc_perms);
6014
6015         ad.type = LSM_AUDIT_DATA_IPC;
6016         ad.u.ipc_id = ipc_perms->key;
6017
6018         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6019 }
6020
6021 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6022 {
6023         struct msg_security_struct *msec;
6024
6025         msec = selinux_msg_msg(msg);
6026         msec->sid = SECINITSID_UNLABELED;
6027
6028         return 0;
6029 }
6030
6031 /* message queue security operations */
6032 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6033 {
6034         struct ipc_security_struct *isec;
6035         struct common_audit_data ad;
6036         u32 sid = current_sid();
6037
6038         isec = selinux_ipc(msq);
6039         ipc_init_security(isec, SECCLASS_MSGQ);
6040
6041         ad.type = LSM_AUDIT_DATA_IPC;
6042         ad.u.ipc_id = msq->key;
6043
6044         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6045                             MSGQ__CREATE, &ad);
6046 }
6047
6048 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6049 {
6050         struct ipc_security_struct *isec;
6051         struct common_audit_data ad;
6052         u32 sid = current_sid();
6053
6054         isec = selinux_ipc(msq);
6055
6056         ad.type = LSM_AUDIT_DATA_IPC;
6057         ad.u.ipc_id = msq->key;
6058
6059         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6060                             MSGQ__ASSOCIATE, &ad);
6061 }
6062
6063 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6064 {
6065         u32 perms;
6066
6067         switch (cmd) {
6068         case IPC_INFO:
6069         case MSG_INFO:
6070                 /* No specific object, just general system-wide information. */
6071                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6072                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6073         case IPC_STAT:
6074         case MSG_STAT:
6075         case MSG_STAT_ANY:
6076                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6077                 break;
6078         case IPC_SET:
6079                 perms = MSGQ__SETATTR;
6080                 break;
6081         case IPC_RMID:
6082                 perms = MSGQ__DESTROY;
6083                 break;
6084         default:
6085                 return 0;
6086         }
6087
6088         return ipc_has_perm(msq, perms);
6089 }
6090
6091 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6092 {
6093         struct ipc_security_struct *isec;
6094         struct msg_security_struct *msec;
6095         struct common_audit_data ad;
6096         u32 sid = current_sid();
6097         int rc;
6098
6099         isec = selinux_ipc(msq);
6100         msec = selinux_msg_msg(msg);
6101
6102         /*
6103          * First time through, need to assign label to the message
6104          */
6105         if (msec->sid == SECINITSID_UNLABELED) {
6106                 /*
6107                  * Compute new sid based on current process and
6108                  * message queue this message will be stored in
6109                  */
6110                 rc = security_transition_sid(sid, isec->sid,
6111                                              SECCLASS_MSG, NULL, &msec->sid);
6112                 if (rc)
6113                         return rc;
6114         }
6115
6116         ad.type = LSM_AUDIT_DATA_IPC;
6117         ad.u.ipc_id = msq->key;
6118
6119         /* Can this process write to the queue? */
6120         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6121                           MSGQ__WRITE, &ad);
6122         if (!rc)
6123                 /* Can this process send the message */
6124                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6125                                   MSG__SEND, &ad);
6126         if (!rc)
6127                 /* Can the message be put in the queue? */
6128                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6129                                   MSGQ__ENQUEUE, &ad);
6130
6131         return rc;
6132 }
6133
6134 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6135                                     struct task_struct *target,
6136                                     long type, int mode)
6137 {
6138         struct ipc_security_struct *isec;
6139         struct msg_security_struct *msec;
6140         struct common_audit_data ad;
6141         u32 sid = task_sid_obj(target);
6142         int rc;
6143
6144         isec = selinux_ipc(msq);
6145         msec = selinux_msg_msg(msg);
6146
6147         ad.type = LSM_AUDIT_DATA_IPC;
6148         ad.u.ipc_id = msq->key;
6149
6150         rc = avc_has_perm(sid, isec->sid,
6151                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6152         if (!rc)
6153                 rc = avc_has_perm(sid, msec->sid,
6154                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6155         return rc;
6156 }
6157
6158 /* Shared Memory security operations */
6159 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6160 {
6161         struct ipc_security_struct *isec;
6162         struct common_audit_data ad;
6163         u32 sid = current_sid();
6164
6165         isec = selinux_ipc(shp);
6166         ipc_init_security(isec, SECCLASS_SHM);
6167
6168         ad.type = LSM_AUDIT_DATA_IPC;
6169         ad.u.ipc_id = shp->key;
6170
6171         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6172                             SHM__CREATE, &ad);
6173 }
6174
6175 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6176 {
6177         struct ipc_security_struct *isec;
6178         struct common_audit_data ad;
6179         u32 sid = current_sid();
6180
6181         isec = selinux_ipc(shp);
6182
6183         ad.type = LSM_AUDIT_DATA_IPC;
6184         ad.u.ipc_id = shp->key;
6185
6186         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6187                             SHM__ASSOCIATE, &ad);
6188 }
6189
6190 /* Note, at this point, shp is locked down */
6191 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6192 {
6193         u32 perms;
6194
6195         switch (cmd) {
6196         case IPC_INFO:
6197         case SHM_INFO:
6198                 /* No specific object, just general system-wide information. */
6199                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6200                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6201         case IPC_STAT:
6202         case SHM_STAT:
6203         case SHM_STAT_ANY:
6204                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6205                 break;
6206         case IPC_SET:
6207                 perms = SHM__SETATTR;
6208                 break;
6209         case SHM_LOCK:
6210         case SHM_UNLOCK:
6211                 perms = SHM__LOCK;
6212                 break;
6213         case IPC_RMID:
6214                 perms = SHM__DESTROY;
6215                 break;
6216         default:
6217                 return 0;
6218         }
6219
6220         return ipc_has_perm(shp, perms);
6221 }
6222
6223 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6224                              char __user *shmaddr, int shmflg)
6225 {
6226         u32 perms;
6227
6228         if (shmflg & SHM_RDONLY)
6229                 perms = SHM__READ;
6230         else
6231                 perms = SHM__READ | SHM__WRITE;
6232
6233         return ipc_has_perm(shp, perms);
6234 }
6235
6236 /* Semaphore security operations */
6237 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6238 {
6239         struct ipc_security_struct *isec;
6240         struct common_audit_data ad;
6241         u32 sid = current_sid();
6242
6243         isec = selinux_ipc(sma);
6244         ipc_init_security(isec, SECCLASS_SEM);
6245
6246         ad.type = LSM_AUDIT_DATA_IPC;
6247         ad.u.ipc_id = sma->key;
6248
6249         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6250                             SEM__CREATE, &ad);
6251 }
6252
6253 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6254 {
6255         struct ipc_security_struct *isec;
6256         struct common_audit_data ad;
6257         u32 sid = current_sid();
6258
6259         isec = selinux_ipc(sma);
6260
6261         ad.type = LSM_AUDIT_DATA_IPC;
6262         ad.u.ipc_id = sma->key;
6263
6264         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6265                             SEM__ASSOCIATE, &ad);
6266 }
6267
6268 /* Note, at this point, sma is locked down */
6269 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6270 {
6271         int err;
6272         u32 perms;
6273
6274         switch (cmd) {
6275         case IPC_INFO:
6276         case SEM_INFO:
6277                 /* No specific object, just general system-wide information. */
6278                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6279                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6280         case GETPID:
6281         case GETNCNT:
6282         case GETZCNT:
6283                 perms = SEM__GETATTR;
6284                 break;
6285         case GETVAL:
6286         case GETALL:
6287                 perms = SEM__READ;
6288                 break;
6289         case SETVAL:
6290         case SETALL:
6291                 perms = SEM__WRITE;
6292                 break;
6293         case IPC_RMID:
6294                 perms = SEM__DESTROY;
6295                 break;
6296         case IPC_SET:
6297                 perms = SEM__SETATTR;
6298                 break;
6299         case IPC_STAT:
6300         case SEM_STAT:
6301         case SEM_STAT_ANY:
6302                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6303                 break;
6304         default:
6305                 return 0;
6306         }
6307
6308         err = ipc_has_perm(sma, perms);
6309         return err;
6310 }
6311
6312 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6313                              struct sembuf *sops, unsigned nsops, int alter)
6314 {
6315         u32 perms;
6316
6317         if (alter)
6318                 perms = SEM__READ | SEM__WRITE;
6319         else
6320                 perms = SEM__READ;
6321
6322         return ipc_has_perm(sma, perms);
6323 }
6324
6325 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6326 {
6327         u32 av = 0;
6328
6329         av = 0;
6330         if (flag & S_IRUGO)
6331                 av |= IPC__UNIX_READ;
6332         if (flag & S_IWUGO)
6333                 av |= IPC__UNIX_WRITE;
6334
6335         if (av == 0)
6336                 return 0;
6337
6338         return ipc_has_perm(ipcp, av);
6339 }
6340
6341 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6342 {
6343         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6344         *secid = isec->sid;
6345 }
6346
6347 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6348 {
6349         if (inode)
6350                 inode_doinit_with_dentry(inode, dentry);
6351 }
6352
6353 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6354                                char **value)
6355 {
6356         const struct task_security_struct *tsec;
6357         int error;
6358         u32 sid;
6359         u32 len;
6360
6361         rcu_read_lock();
6362         tsec = selinux_cred(__task_cred(p));
6363         if (p != current) {
6364                 error = avc_has_perm(current_sid(), tsec->sid,
6365                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6366                 if (error)
6367                         goto err_unlock;
6368         }
6369         switch (attr) {
6370         case LSM_ATTR_CURRENT:
6371                 sid = tsec->sid;
6372                 break;
6373         case LSM_ATTR_PREV:
6374                 sid = tsec->osid;
6375                 break;
6376         case LSM_ATTR_EXEC:
6377                 sid = tsec->exec_sid;
6378                 break;
6379         case LSM_ATTR_FSCREATE:
6380                 sid = tsec->create_sid;
6381                 break;
6382         case LSM_ATTR_KEYCREATE:
6383                 sid = tsec->keycreate_sid;
6384                 break;
6385         case LSM_ATTR_SOCKCREATE:
6386                 sid = tsec->sockcreate_sid;
6387                 break;
6388         default:
6389                 error = -EOPNOTSUPP;
6390                 goto err_unlock;
6391         }
6392         rcu_read_unlock();
6393
6394         if (sid == SECSID_NULL) {
6395                 *value = NULL;
6396                 return 0;
6397         }
6398
6399         error = security_sid_to_context(sid, value, &len);
6400         if (error)
6401                 return error;
6402         return len;
6403
6404 err_unlock:
6405         rcu_read_unlock();
6406         return error;
6407 }
6408
6409 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6410 {
6411         struct task_security_struct *tsec;
6412         struct cred *new;
6413         u32 mysid = current_sid(), sid = 0, ptsid;
6414         int error;
6415         char *str = value;
6416
6417         /*
6418          * Basic control over ability to set these attributes at all.
6419          */
6420         switch (attr) {
6421         case LSM_ATTR_EXEC:
6422                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6423                                      PROCESS__SETEXEC, NULL);
6424                 break;
6425         case LSM_ATTR_FSCREATE:
6426                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6427                                      PROCESS__SETFSCREATE, NULL);
6428                 break;
6429         case LSM_ATTR_KEYCREATE:
6430                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6431                                      PROCESS__SETKEYCREATE, NULL);
6432                 break;
6433         case LSM_ATTR_SOCKCREATE:
6434                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6435                                      PROCESS__SETSOCKCREATE, NULL);
6436                 break;
6437         case LSM_ATTR_CURRENT:
6438                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6439                                      PROCESS__SETCURRENT, NULL);
6440                 break;
6441         default:
6442                 error = -EOPNOTSUPP;
6443                 break;
6444         }
6445         if (error)
6446                 return error;
6447
6448         /* Obtain a SID for the context, if one was specified. */
6449         if (size && str[0] && str[0] != '\n') {
6450                 if (str[size-1] == '\n') {
6451                         str[size-1] = 0;
6452                         size--;
6453                 }
6454                 error = security_context_to_sid(value, size,
6455                                                 &sid, GFP_KERNEL);
6456                 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6457                         if (!has_cap_mac_admin(true)) {
6458                                 struct audit_buffer *ab;
6459                                 size_t audit_size;
6460
6461                                 /* We strip a nul only if it is at the end,
6462                                  * otherwise the context contains a nul and
6463                                  * we should audit that */
6464                                 if (str[size - 1] == '\0')
6465                                         audit_size = size - 1;
6466                                 else
6467                                         audit_size = size;
6468                                 ab = audit_log_start(audit_context(),
6469                                                      GFP_ATOMIC,
6470                                                      AUDIT_SELINUX_ERR);
6471                                 if (!ab)
6472                                         return error;
6473                                 audit_log_format(ab, "op=fscreate invalid_context=");
6474                                 audit_log_n_untrustedstring(ab, value,
6475                                                             audit_size);
6476                                 audit_log_end(ab);
6477
6478                                 return error;
6479                         }
6480                         error = security_context_to_sid_force(value, size,
6481                                                         &sid);
6482                 }
6483                 if (error)
6484                         return error;
6485         }
6486
6487         new = prepare_creds();
6488         if (!new)
6489                 return -ENOMEM;
6490
6491         /* Permission checking based on the specified context is
6492            performed during the actual operation (execve,
6493            open/mkdir/...), when we know the full context of the
6494            operation.  See selinux_bprm_creds_for_exec for the execve
6495            checks and may_create for the file creation checks. The
6496            operation will then fail if the context is not permitted. */
6497         tsec = selinux_cred(new);
6498         if (attr == LSM_ATTR_EXEC) {
6499                 tsec->exec_sid = sid;
6500         } else if (attr == LSM_ATTR_FSCREATE) {
6501                 tsec->create_sid = sid;
6502         } else if (attr == LSM_ATTR_KEYCREATE) {
6503                 if (sid) {
6504                         error = avc_has_perm(mysid, sid,
6505                                              SECCLASS_KEY, KEY__CREATE, NULL);
6506                         if (error)
6507                                 goto abort_change;
6508                 }
6509                 tsec->keycreate_sid = sid;
6510         } else if (attr == LSM_ATTR_SOCKCREATE) {
6511                 tsec->sockcreate_sid = sid;
6512         } else if (attr == LSM_ATTR_CURRENT) {
6513                 error = -EINVAL;
6514                 if (sid == 0)
6515                         goto abort_change;
6516
6517                 if (!current_is_single_threaded()) {
6518                         error = security_bounded_transition(tsec->sid, sid);
6519                         if (error)
6520                                 goto abort_change;
6521                 }
6522
6523                 /* Check permissions for the transition. */
6524                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6525                                      PROCESS__DYNTRANSITION, NULL);
6526                 if (error)
6527                         goto abort_change;
6528
6529                 /* Check for ptracing, and update the task SID if ok.
6530                    Otherwise, leave SID unchanged and fail. */
6531                 ptsid = ptrace_parent_sid();
6532                 if (ptsid != 0) {
6533                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6534                                              PROCESS__PTRACE, NULL);
6535                         if (error)
6536                                 goto abort_change;
6537                 }
6538
6539                 tsec->sid = sid;
6540         } else {
6541                 error = -EINVAL;
6542                 goto abort_change;
6543         }
6544
6545         commit_creds(new);
6546         return size;
6547
6548 abort_change:
6549         abort_creds(new);
6550         return error;
6551 }
6552
6553 /**
6554  * selinux_getselfattr - Get SELinux current task attributes
6555  * @attr: the requested attribute
6556  * @ctx: buffer to receive the result
6557  * @size: buffer size (input), buffer size used (output)
6558  * @flags: unused
6559  *
6560  * Fill the passed user space @ctx with the details of the requested
6561  * attribute.
6562  *
6563  * Returns the number of attributes on success, an error code otherwise.
6564  * There will only ever be one attribute.
6565  */
6566 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6567                                u32 *size, u32 flags)
6568 {
6569         int rc;
6570         char *val = NULL;
6571         int val_len;
6572
6573         val_len = selinux_lsm_getattr(attr, current, &val);
6574         if (val_len < 0)
6575                 return val_len;
6576         rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6577         kfree(val);
6578         return (!rc ? 1 : rc);
6579 }
6580
6581 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6582                                u32 size, u32 flags)
6583 {
6584         int rc;
6585
6586         rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6587         if (rc > 0)
6588                 return 0;
6589         return rc;
6590 }
6591
6592 static int selinux_getprocattr(struct task_struct *p,
6593                                const char *name, char **value)
6594 {
6595         unsigned int attr = lsm_name_to_attr(name);
6596         int rc;
6597
6598         if (attr) {
6599                 rc = selinux_lsm_getattr(attr, p, value);
6600                 if (rc != -EOPNOTSUPP)
6601                         return rc;
6602         }
6603
6604         return -EINVAL;
6605 }
6606
6607 static int selinux_setprocattr(const char *name, void *value, size_t size)
6608 {
6609         int attr = lsm_name_to_attr(name);
6610
6611         if (attr)
6612                 return selinux_lsm_setattr(attr, value, size);
6613         return -EINVAL;
6614 }
6615
6616 static int selinux_ismaclabel(const char *name)
6617 {
6618         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6619 }
6620
6621 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6622 {
6623         return security_sid_to_context(secid,
6624                                        secdata, seclen);
6625 }
6626
6627 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6628 {
6629         return security_context_to_sid(secdata, seclen,
6630                                        secid, GFP_KERNEL);
6631 }
6632
6633 static void selinux_release_secctx(char *secdata, u32 seclen)
6634 {
6635         kfree(secdata);
6636 }
6637
6638 static void selinux_inode_invalidate_secctx(struct inode *inode)
6639 {
6640         struct inode_security_struct *isec = selinux_inode(inode);
6641
6642         spin_lock(&isec->lock);
6643         isec->initialized = LABEL_INVALID;
6644         spin_unlock(&isec->lock);
6645 }
6646
6647 /*
6648  *      called with inode->i_mutex locked
6649  */
6650 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6651 {
6652         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6653                                            ctx, ctxlen, 0);
6654         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6655         return rc == -EOPNOTSUPP ? 0 : rc;
6656 }
6657
6658 /*
6659  *      called with inode->i_mutex locked
6660  */
6661 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6662 {
6663         return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6664                                      ctx, ctxlen, 0, NULL);
6665 }
6666
6667 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6668 {
6669         int len = 0;
6670         len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6671                                         XATTR_SELINUX_SUFFIX, ctx, true);
6672         if (len < 0)
6673                 return len;
6674         *ctxlen = len;
6675         return 0;
6676 }
6677 #ifdef CONFIG_KEYS
6678
6679 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6680                              unsigned long flags)
6681 {
6682         const struct task_security_struct *tsec;
6683         struct key_security_struct *ksec;
6684
6685         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6686         if (!ksec)
6687                 return -ENOMEM;
6688
6689         tsec = selinux_cred(cred);
6690         if (tsec->keycreate_sid)
6691                 ksec->sid = tsec->keycreate_sid;
6692         else
6693                 ksec->sid = tsec->sid;
6694
6695         k->security = ksec;
6696         return 0;
6697 }
6698
6699 static void selinux_key_free(struct key *k)
6700 {
6701         struct key_security_struct *ksec = k->security;
6702
6703         k->security = NULL;
6704         kfree(ksec);
6705 }
6706
6707 static int selinux_key_permission(key_ref_t key_ref,
6708                                   const struct cred *cred,
6709                                   enum key_need_perm need_perm)
6710 {
6711         struct key *key;
6712         struct key_security_struct *ksec;
6713         u32 perm, sid;
6714
6715         switch (need_perm) {
6716         case KEY_NEED_VIEW:
6717                 perm = KEY__VIEW;
6718                 break;
6719         case KEY_NEED_READ:
6720                 perm = KEY__READ;
6721                 break;
6722         case KEY_NEED_WRITE:
6723                 perm = KEY__WRITE;
6724                 break;
6725         case KEY_NEED_SEARCH:
6726                 perm = KEY__SEARCH;
6727                 break;
6728         case KEY_NEED_LINK:
6729                 perm = KEY__LINK;
6730                 break;
6731         case KEY_NEED_SETATTR:
6732                 perm = KEY__SETATTR;
6733                 break;
6734         case KEY_NEED_UNLINK:
6735         case KEY_SYSADMIN_OVERRIDE:
6736         case KEY_AUTHTOKEN_OVERRIDE:
6737         case KEY_DEFER_PERM_CHECK:
6738                 return 0;
6739         default:
6740                 WARN_ON(1);
6741                 return -EPERM;
6742
6743         }
6744
6745         sid = cred_sid(cred);
6746         key = key_ref_to_ptr(key_ref);
6747         ksec = key->security;
6748
6749         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6750 }
6751
6752 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6753 {
6754         struct key_security_struct *ksec = key->security;
6755         char *context = NULL;
6756         unsigned len;
6757         int rc;
6758
6759         rc = security_sid_to_context(ksec->sid,
6760                                      &context, &len);
6761         if (!rc)
6762                 rc = len;
6763         *_buffer = context;
6764         return rc;
6765 }
6766
6767 #ifdef CONFIG_KEY_NOTIFICATIONS
6768 static int selinux_watch_key(struct key *key)
6769 {
6770         struct key_security_struct *ksec = key->security;
6771         u32 sid = current_sid();
6772
6773         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6774 }
6775 #endif
6776 #endif
6777
6778 #ifdef CONFIG_SECURITY_INFINIBAND
6779 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6780 {
6781         struct common_audit_data ad;
6782         int err;
6783         u32 sid = 0;
6784         struct ib_security_struct *sec = ib_sec;
6785         struct lsm_ibpkey_audit ibpkey;
6786
6787         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6788         if (err)
6789                 return err;
6790
6791         ad.type = LSM_AUDIT_DATA_IBPKEY;
6792         ibpkey.subnet_prefix = subnet_prefix;
6793         ibpkey.pkey = pkey_val;
6794         ad.u.ibpkey = &ibpkey;
6795         return avc_has_perm(sec->sid, sid,
6796                             SECCLASS_INFINIBAND_PKEY,
6797                             INFINIBAND_PKEY__ACCESS, &ad);
6798 }
6799
6800 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6801                                             u8 port_num)
6802 {
6803         struct common_audit_data ad;
6804         int err;
6805         u32 sid = 0;
6806         struct ib_security_struct *sec = ib_sec;
6807         struct lsm_ibendport_audit ibendport;
6808
6809         err = security_ib_endport_sid(dev_name, port_num,
6810                                       &sid);
6811
6812         if (err)
6813                 return err;
6814
6815         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6816         ibendport.dev_name = dev_name;
6817         ibendport.port = port_num;
6818         ad.u.ibendport = &ibendport;
6819         return avc_has_perm(sec->sid, sid,
6820                             SECCLASS_INFINIBAND_ENDPORT,
6821                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6822 }
6823
6824 static int selinux_ib_alloc_security(void **ib_sec)
6825 {
6826         struct ib_security_struct *sec;
6827
6828         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6829         if (!sec)
6830                 return -ENOMEM;
6831         sec->sid = current_sid();
6832
6833         *ib_sec = sec;
6834         return 0;
6835 }
6836
6837 static void selinux_ib_free_security(void *ib_sec)
6838 {
6839         kfree(ib_sec);
6840 }
6841 #endif
6842
6843 #ifdef CONFIG_BPF_SYSCALL
6844 static int selinux_bpf(int cmd, union bpf_attr *attr,
6845                                      unsigned int size)
6846 {
6847         u32 sid = current_sid();
6848         int ret;
6849
6850         switch (cmd) {
6851         case BPF_MAP_CREATE:
6852                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6853                                    NULL);
6854                 break;
6855         case BPF_PROG_LOAD:
6856                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6857                                    NULL);
6858                 break;
6859         default:
6860                 ret = 0;
6861                 break;
6862         }
6863
6864         return ret;
6865 }
6866
6867 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6868 {
6869         u32 av = 0;
6870
6871         if (fmode & FMODE_READ)
6872                 av |= BPF__MAP_READ;
6873         if (fmode & FMODE_WRITE)
6874                 av |= BPF__MAP_WRITE;
6875         return av;
6876 }
6877
6878 /* This function will check the file pass through unix socket or binder to see
6879  * if it is a bpf related object. And apply corresponding checks on the bpf
6880  * object based on the type. The bpf maps and programs, not like other files and
6881  * socket, are using a shared anonymous inode inside the kernel as their inode.
6882  * So checking that inode cannot identify if the process have privilege to
6883  * access the bpf object and that's why we have to add this additional check in
6884  * selinux_file_receive and selinux_binder_transfer_files.
6885  */
6886 static int bpf_fd_pass(const struct file *file, u32 sid)
6887 {
6888         struct bpf_security_struct *bpfsec;
6889         struct bpf_prog *prog;
6890         struct bpf_map *map;
6891         int ret;
6892
6893         if (file->f_op == &bpf_map_fops) {
6894                 map = file->private_data;
6895                 bpfsec = map->security;
6896                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6897                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6898                 if (ret)
6899                         return ret;
6900         } else if (file->f_op == &bpf_prog_fops) {
6901                 prog = file->private_data;
6902                 bpfsec = prog->aux->security;
6903                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6904                                    BPF__PROG_RUN, NULL);
6905                 if (ret)
6906                         return ret;
6907         }
6908         return 0;
6909 }
6910
6911 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6912 {
6913         u32 sid = current_sid();
6914         struct bpf_security_struct *bpfsec;
6915
6916         bpfsec = map->security;
6917         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6918                             bpf_map_fmode_to_av(fmode), NULL);
6919 }
6920
6921 static int selinux_bpf_prog(struct bpf_prog *prog)
6922 {
6923         u32 sid = current_sid();
6924         struct bpf_security_struct *bpfsec;
6925
6926         bpfsec = prog->aux->security;
6927         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6928                             BPF__PROG_RUN, NULL);
6929 }
6930
6931 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6932                                   struct bpf_token *token)
6933 {
6934         struct bpf_security_struct *bpfsec;
6935
6936         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6937         if (!bpfsec)
6938                 return -ENOMEM;
6939
6940         bpfsec->sid = current_sid();
6941         map->security = bpfsec;
6942
6943         return 0;
6944 }
6945
6946 static void selinux_bpf_map_free(struct bpf_map *map)
6947 {
6948         struct bpf_security_struct *bpfsec = map->security;
6949
6950         map->security = NULL;
6951         kfree(bpfsec);
6952 }
6953
6954 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6955                                  struct bpf_token *token)
6956 {
6957         struct bpf_security_struct *bpfsec;
6958
6959         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6960         if (!bpfsec)
6961                 return -ENOMEM;
6962
6963         bpfsec->sid = current_sid();
6964         prog->aux->security = bpfsec;
6965
6966         return 0;
6967 }
6968
6969 static void selinux_bpf_prog_free(struct bpf_prog *prog)
6970 {
6971         struct bpf_security_struct *bpfsec = prog->aux->security;
6972
6973         prog->aux->security = NULL;
6974         kfree(bpfsec);
6975 }
6976
6977 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
6978                                     struct path *path)
6979 {
6980         struct bpf_security_struct *bpfsec;
6981
6982         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6983         if (!bpfsec)
6984                 return -ENOMEM;
6985
6986         bpfsec->sid = current_sid();
6987         token->security = bpfsec;
6988
6989         return 0;
6990 }
6991
6992 static void selinux_bpf_token_free(struct bpf_token *token)
6993 {
6994         struct bpf_security_struct *bpfsec = token->security;
6995
6996         token->security = NULL;
6997         kfree(bpfsec);
6998 }
6999 #endif
7000
7001 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
7002         .lbs_cred = sizeof(struct task_security_struct),
7003         .lbs_file = sizeof(struct file_security_struct),
7004         .lbs_inode = sizeof(struct inode_security_struct),
7005         .lbs_ipc = sizeof(struct ipc_security_struct),
7006         .lbs_msg_msg = sizeof(struct msg_security_struct),
7007         .lbs_superblock = sizeof(struct superblock_security_struct),
7008         .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7009 };
7010
7011 #ifdef CONFIG_PERF_EVENTS
7012 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7013 {
7014         u32 requested, sid = current_sid();
7015
7016         if (type == PERF_SECURITY_OPEN)
7017                 requested = PERF_EVENT__OPEN;
7018         else if (type == PERF_SECURITY_CPU)
7019                 requested = PERF_EVENT__CPU;
7020         else if (type == PERF_SECURITY_KERNEL)
7021                 requested = PERF_EVENT__KERNEL;
7022         else if (type == PERF_SECURITY_TRACEPOINT)
7023                 requested = PERF_EVENT__TRACEPOINT;
7024         else
7025                 return -EINVAL;
7026
7027         return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7028                             requested, NULL);
7029 }
7030
7031 static int selinux_perf_event_alloc(struct perf_event *event)
7032 {
7033         struct perf_event_security_struct *perfsec;
7034
7035         perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
7036         if (!perfsec)
7037                 return -ENOMEM;
7038
7039         perfsec->sid = current_sid();
7040         event->security = perfsec;
7041
7042         return 0;
7043 }
7044
7045 static void selinux_perf_event_free(struct perf_event *event)
7046 {
7047         struct perf_event_security_struct *perfsec = event->security;
7048
7049         event->security = NULL;
7050         kfree(perfsec);
7051 }
7052
7053 static int selinux_perf_event_read(struct perf_event *event)
7054 {
7055         struct perf_event_security_struct *perfsec = event->security;
7056         u32 sid = current_sid();
7057
7058         return avc_has_perm(sid, perfsec->sid,
7059                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7060 }
7061
7062 static int selinux_perf_event_write(struct perf_event *event)
7063 {
7064         struct perf_event_security_struct *perfsec = event->security;
7065         u32 sid = current_sid();
7066
7067         return avc_has_perm(sid, perfsec->sid,
7068                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7069 }
7070 #endif
7071
7072 #ifdef CONFIG_IO_URING
7073 /**
7074  * selinux_uring_override_creds - check the requested cred override
7075  * @new: the target creds
7076  *
7077  * Check to see if the current task is allowed to override it's credentials
7078  * to service an io_uring operation.
7079  */
7080 static int selinux_uring_override_creds(const struct cred *new)
7081 {
7082         return avc_has_perm(current_sid(), cred_sid(new),
7083                             SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7084 }
7085
7086 /**
7087  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7088  *
7089  * Check to see if the current task is allowed to create a new io_uring
7090  * kernel polling thread.
7091  */
7092 static int selinux_uring_sqpoll(void)
7093 {
7094         u32 sid = current_sid();
7095
7096         return avc_has_perm(sid, sid,
7097                             SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7098 }
7099
7100 /**
7101  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7102  * @ioucmd: the io_uring command structure
7103  *
7104  * Check to see if the current domain is allowed to execute an
7105  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7106  *
7107  */
7108 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7109 {
7110         struct file *file = ioucmd->file;
7111         struct inode *inode = file_inode(file);
7112         struct inode_security_struct *isec = selinux_inode(inode);
7113         struct common_audit_data ad;
7114
7115         ad.type = LSM_AUDIT_DATA_FILE;
7116         ad.u.file = file;
7117
7118         return avc_has_perm(current_sid(), isec->sid,
7119                             SECCLASS_IO_URING, IO_URING__CMD, &ad);
7120 }
7121 #endif /* CONFIG_IO_URING */
7122
7123 static const struct lsm_id selinux_lsmid = {
7124         .name = "selinux",
7125         .id = LSM_ID_SELINUX,
7126 };
7127
7128 /*
7129  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7130  * 1. any hooks that don't belong to (2.) or (3.) below,
7131  * 2. hooks that both access structures allocated by other hooks, and allocate
7132  *    structures that can be later accessed by other hooks (mostly "cloning"
7133  *    hooks),
7134  * 3. hooks that only allocate structures that can be later accessed by other
7135  *    hooks ("allocating" hooks).
7136  *
7137  * Please follow block comment delimiters in the list to keep this order.
7138  */
7139 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7140         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7141         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7142         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7143         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7144
7145         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7146         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7147         LSM_HOOK_INIT(capget, selinux_capget),
7148         LSM_HOOK_INIT(capset, selinux_capset),
7149         LSM_HOOK_INIT(capable, selinux_capable),
7150         LSM_HOOK_INIT(quotactl, selinux_quotactl),
7151         LSM_HOOK_INIT(quota_on, selinux_quota_on),
7152         LSM_HOOK_INIT(syslog, selinux_syslog),
7153         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7154
7155         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7156
7157         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7158         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7159         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7160
7161         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7162         LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7163         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7164         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7165         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7166         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7167         LSM_HOOK_INIT(sb_mount, selinux_mount),
7168         LSM_HOOK_INIT(sb_umount, selinux_umount),
7169         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7170         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7171
7172         LSM_HOOK_INIT(move_mount, selinux_move_mount),
7173
7174         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7175         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7176
7177         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7178         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7179         LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7180         LSM_HOOK_INIT(inode_create, selinux_inode_create),
7181         LSM_HOOK_INIT(inode_link, selinux_inode_link),
7182         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7183         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7184         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7185         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7186         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7187         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7188         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7189         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7190         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7191         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7192         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7193         LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap),
7194         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7195         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7196         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7197         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7198         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7199         LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7200         LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7201         LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7202         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7203         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7204         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7205         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7206         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7207         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7208         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7209
7210         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7211
7212         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7213         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7214         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7215         LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7216         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7217         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7218         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7219         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7220         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7221         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7222         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7223         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7224
7225         LSM_HOOK_INIT(file_open, selinux_file_open),
7226
7227         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7228         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7229         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7230         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
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_getsecid_subj, selinux_current_getsecid_subj),
7240         LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_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_getsecid, selinux_ipc_getsecid),
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_free_security, selinux_tun_dev_free_security),
7321         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7322         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7323         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7324         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7325 #ifdef CONFIG_SECURITY_INFINIBAND
7326         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7327         LSM_HOOK_INIT(ib_endport_manage_subnet,
7328                       selinux_ib_endport_manage_subnet),
7329         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7330 #endif
7331 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7332         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7333         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7334         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7335         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7336         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7337         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7338                         selinux_xfrm_state_pol_flow_match),
7339         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7340 #endif
7341
7342 #ifdef CONFIG_KEYS
7343         LSM_HOOK_INIT(key_free, selinux_key_free),
7344         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7345         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7346 #ifdef CONFIG_KEY_NOTIFICATIONS
7347         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7348 #endif
7349 #endif
7350
7351 #ifdef CONFIG_AUDIT
7352         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7353         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7354         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7355 #endif
7356
7357 #ifdef CONFIG_BPF_SYSCALL
7358         LSM_HOOK_INIT(bpf, selinux_bpf),
7359         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7360         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7361         LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7362         LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7363         LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7364 #endif
7365
7366 #ifdef CONFIG_PERF_EVENTS
7367         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7368         LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7369         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7370         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7371 #endif
7372
7373 #ifdef CONFIG_IO_URING
7374         LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7375         LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7376         LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7377 #endif
7378
7379         /*
7380          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7381          */
7382         LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7383         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7384         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7385         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7386 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7387         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7388 #endif
7389
7390         /*
7391          * PUT "ALLOCATING" HOOKS HERE
7392          */
7393         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7394         LSM_HOOK_INIT(msg_queue_alloc_security,
7395                       selinux_msg_queue_alloc_security),
7396         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7397         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7398         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7399         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7400         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7401         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7402         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7403         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7404 #ifdef CONFIG_SECURITY_INFINIBAND
7405         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7406 #endif
7407 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7408         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7409         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7410         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7411                       selinux_xfrm_state_alloc_acquire),
7412 #endif
7413 #ifdef CONFIG_KEYS
7414         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7415 #endif
7416 #ifdef CONFIG_AUDIT
7417         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7418 #endif
7419 #ifdef CONFIG_BPF_SYSCALL
7420         LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7421         LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7422         LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7423 #endif
7424 #ifdef CONFIG_PERF_EVENTS
7425         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7426 #endif
7427 };
7428
7429 static __init int selinux_init(void)
7430 {
7431         pr_info("SELinux:  Initializing.\n");
7432
7433         memset(&selinux_state, 0, sizeof(selinux_state));
7434         enforcing_set(selinux_enforcing_boot);
7435         selinux_avc_init();
7436         mutex_init(&selinux_state.status_lock);
7437         mutex_init(&selinux_state.policy_mutex);
7438
7439         /* Set the security state for the initial task. */
7440         cred_init_security();
7441
7442         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7443         if (!default_noexec)
7444                 pr_notice("SELinux:  virtual memory is executable by default\n");
7445
7446         avc_init();
7447
7448         avtab_cache_init();
7449
7450         ebitmap_cache_init();
7451
7452         hashtab_cache_init();
7453
7454         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7455                            &selinux_lsmid);
7456
7457         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7458                 panic("SELinux: Unable to register AVC netcache callback\n");
7459
7460         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7461                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7462
7463         if (selinux_enforcing_boot)
7464                 pr_debug("SELinux:  Starting in enforcing mode\n");
7465         else
7466                 pr_debug("SELinux:  Starting in permissive mode\n");
7467
7468         fs_validate_description("selinux", selinux_fs_parameters);
7469
7470         return 0;
7471 }
7472
7473 static void delayed_superblock_init(struct super_block *sb, void *unused)
7474 {
7475         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7476 }
7477
7478 void selinux_complete_init(void)
7479 {
7480         pr_debug("SELinux:  Completing initialization.\n");
7481
7482         /* Set up any superblocks initialized prior to the policy load. */
7483         pr_debug("SELinux:  Setting up existing superblocks.\n");
7484         iterate_supers(delayed_superblock_init, NULL);
7485 }
7486
7487 /* SELinux requires early initialization in order to label
7488    all processes and objects when they are created. */
7489 DEFINE_LSM(selinux) = {
7490         .name = "selinux",
7491         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7492         .enabled = &selinux_enabled_boot,
7493         .blobs = &selinux_blob_sizes,
7494         .init = selinux_init,
7495 };
7496
7497 #if defined(CONFIG_NETFILTER)
7498 static const struct nf_hook_ops selinux_nf_ops[] = {
7499         {
7500                 .hook =         selinux_ip_postroute,
7501                 .pf =           NFPROTO_IPV4,
7502                 .hooknum =      NF_INET_POST_ROUTING,
7503                 .priority =     NF_IP_PRI_SELINUX_LAST,
7504         },
7505         {
7506                 .hook =         selinux_ip_forward,
7507                 .pf =           NFPROTO_IPV4,
7508                 .hooknum =      NF_INET_FORWARD,
7509                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7510         },
7511         {
7512                 .hook =         selinux_ip_output,
7513                 .pf =           NFPROTO_IPV4,
7514                 .hooknum =      NF_INET_LOCAL_OUT,
7515                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7516         },
7517 #if IS_ENABLED(CONFIG_IPV6)
7518         {
7519                 .hook =         selinux_ip_postroute,
7520                 .pf =           NFPROTO_IPV6,
7521                 .hooknum =      NF_INET_POST_ROUTING,
7522                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7523         },
7524         {
7525                 .hook =         selinux_ip_forward,
7526                 .pf =           NFPROTO_IPV6,
7527                 .hooknum =      NF_INET_FORWARD,
7528                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7529         },
7530         {
7531                 .hook =         selinux_ip_output,
7532                 .pf =           NFPROTO_IPV6,
7533                 .hooknum =      NF_INET_LOCAL_OUT,
7534                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7535         },
7536 #endif  /* IPV6 */
7537 };
7538
7539 static int __net_init selinux_nf_register(struct net *net)
7540 {
7541         return nf_register_net_hooks(net, selinux_nf_ops,
7542                                      ARRAY_SIZE(selinux_nf_ops));
7543 }
7544
7545 static void __net_exit selinux_nf_unregister(struct net *net)
7546 {
7547         nf_unregister_net_hooks(net, selinux_nf_ops,
7548                                 ARRAY_SIZE(selinux_nf_ops));
7549 }
7550
7551 static struct pernet_operations selinux_net_ops = {
7552         .init = selinux_nf_register,
7553         .exit = selinux_nf_unregister,
7554 };
7555
7556 static int __init selinux_nf_ip_init(void)
7557 {
7558         int err;
7559
7560         if (!selinux_enabled_boot)
7561                 return 0;
7562
7563         pr_debug("SELinux:  Registering netfilter hooks\n");
7564
7565         err = register_pernet_subsys(&selinux_net_ops);
7566         if (err)
7567                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7568
7569         return 0;
7570 }
7571 __initcall(selinux_nf_ip_init);
7572 #endif /* CONFIG_NETFILTER */