security/selinux/hooks.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  NSA 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 <linux/bpf.h>
  89 #include <linux/kernfs.h>
  90 #include <linux/stringhash.h>   /* for hashlen_string() */
  91 #include <uapi/linux/mount.h>
  92 #include <linux/fsnotify.h>
  93 #include <linux/fanotify.h>
  94 #include <linux/io_uring.h>
  95
  96 #include "avc.h"
  97 #include "objsec.h"
  98 #include "netif.h"
  99 #include "netnode.h"
 100 #include "netport.h"
 101 #include "ibpkey.h"
 102 #include "xfrm.h"
 103 #include "netlabel.h"
 104 #include "audit.h"
 105 #include "avc_ss.h"
 106
 107 struct selinux_state selinux_state;
 108
 109 /* SECMARK reference count */
 110 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 111
 112 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 113 static int selinux_enforcing_boot __initdata;
 114
 115 static int __init enforcing_setup(char *str)
 116 {
 117         unsigned long enforcing;
 118         if (!kstrtoul(str, 0, &enforcing))
 119                 selinux_enforcing_boot = enforcing ? 1 : 0;
 120         return 1;
 121 }
 122 __setup("enforcing=", enforcing_setup);
 123 #else
 124 #define selinux_enforcing_boot 1
 125 #endif
 126
 127 int selinux_enabled_boot __initdata = 1;
 128 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 129 static int __init selinux_enabled_setup(char *str)
 130 {
 131         unsigned long enabled;
 132         if (!kstrtoul(str, 0, &enabled))
 133                 selinux_enabled_boot = enabled ? 1 : 0;
 134         return 1;
 135 }
 136 __setup("selinux=", selinux_enabled_setup);
 137 #endif
 138
 139 static unsigned int selinux_checkreqprot_boot =
 140         CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
 141
 142 static int __init checkreqprot_setup(char *str)
 143 {
 144         unsigned long checkreqprot;
 145
 146         if (!kstrtoul(str, 0, &checkreqprot)) {
 147                 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
 148                 if (checkreqprot)
 149                         pr_err("SELinux: checkreqprot set to 1 via kernel parameter.  This is deprecated and will be rejected in a future kernel release.\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 /*
 232  * get the objective security ID of a task
 233  */
 234 static inline u32 task_sid_obj(const struct task_struct *task)
 235 {
 236         u32 sid;
 237
 238         rcu_read_lock();
 239         sid = cred_sid(__task_cred(task));
 240         rcu_read_unlock();
 241         return sid;
 242 }
 243
 244 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 245
 246 /*
 247  * Try reloading inode security labels that have been marked as invalid.  The
 248  * @may_sleep parameter indicates when sleeping and thus reloading labels is
 249  * allowed; when set to false, returns -ECHILD when the label is
 250  * invalid.  The @dentry parameter should be set to a dentry of the inode.
 251  */
 252 static int __inode_security_revalidate(struct inode *inode,
 253                                        struct dentry *dentry,
 254                                        bool may_sleep)
 255 {
 256         struct inode_security_struct *isec = selinux_inode(inode);
 257
 258         might_sleep_if(may_sleep);
 259
 260         if (selinux_initialized(&selinux_state) &&
 261             isec->initialized != LABEL_INITIALIZED) {
 262                 if (!may_sleep)
 263                         return -ECHILD;
 264
 265                 /*
 266                  * Try reloading the inode security label.  This will fail if
 267                  * @opt_dentry is NULL and no dentry for this inode can be
 268                  * found; in that case, continue using the old label.
 269                  */
 270                 inode_doinit_with_dentry(inode, dentry);
 271         }
 272         return 0;
 273 }
 274
 275 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 276 {
 277         return selinux_inode(inode);
 278 }
 279
 280 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 281 {
 282         int error;
 283
 284         error = __inode_security_revalidate(inode, NULL, !rcu);
 285         if (error)
 286                 return ERR_PTR(error);
 287         return selinux_inode(inode);
 288 }
 289
 290 /*
 291  * Get the security label of an inode.
 292  */
 293 static struct inode_security_struct *inode_security(struct inode *inode)
 294 {
 295         __inode_security_revalidate(inode, NULL, true);
 296         return selinux_inode(inode);
 297 }
 298
 299 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 300 {
 301         struct inode *inode = d_backing_inode(dentry);
 302
 303         return selinux_inode(inode);
 304 }
 305
 306 /*
 307  * Get the security label of a dentry's backing inode.
 308  */
 309 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 310 {
 311         struct inode *inode = d_backing_inode(dentry);
 312
 313         __inode_security_revalidate(inode, dentry, true);
 314         return selinux_inode(inode);
 315 }
 316
 317 static void inode_free_security(struct inode *inode)
 318 {
 319         struct inode_security_struct *isec = selinux_inode(inode);
 320         struct superblock_security_struct *sbsec;
 321
 322         if (!isec)
 323                 return;
 324         sbsec = selinux_superblock(inode->i_sb);
 325         /*
 326          * As not all inode security structures are in a list, we check for
 327          * empty list outside of the lock to make sure that we won't waste
 328          * time taking a lock doing nothing.
 329          *
 330          * The list_del_init() function can be safely called more than once.
 331          * It should not be possible for this function to be called with
 332          * concurrent list_add(), but for better safety against future changes
 333          * in the code, we use list_empty_careful() here.
 334          */
 335         if (!list_empty_careful(&isec->list)) {
 336                 spin_lock(&sbsec->isec_lock);
 337                 list_del_init(&isec->list);
 338                 spin_unlock(&sbsec->isec_lock);
 339         }
 340 }
 341
 342 struct selinux_mnt_opts {
 343         u32 fscontext_sid;
 344         u32 context_sid;
 345         u32 rootcontext_sid;
 346         u32 defcontext_sid;
 347 };
 348
 349 static void selinux_free_mnt_opts(void *mnt_opts)
 350 {
 351         kfree(mnt_opts);
 352 }
 353
 354 enum {
 355         Opt_error = -1,
 356         Opt_context = 0,
 357         Opt_defcontext = 1,
 358         Opt_fscontext = 2,
 359         Opt_rootcontext = 3,
 360         Opt_seclabel = 4,
 361 };
 362
 363 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
 364 static struct {
 365         const char *name;
 366         int len;
 367         int opt;
 368         bool has_arg;
 369 } tokens[] = {
 370         A(context, true),
 371         A(fscontext, true),
 372         A(defcontext, true),
 373         A(rootcontext, true),
 374         A(seclabel, false),
 375 };
 376 #undef A
 377
 378 static int match_opt_prefix(char *s, int l, char **arg)
 379 {
 380         int i;
 381
 382         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 383                 size_t len = tokens[i].len;
 384                 if (len > l || memcmp(s, tokens[i].name, len))
 385                         continue;
 386                 if (tokens[i].has_arg) {
 387                         if (len == l || s[len] != '=')
 388                                 continue;
 389                         *arg = s + len + 1;
 390                 } else if (len != l)
 391                         continue;
 392                 return tokens[i].opt;
 393         }
 394         return Opt_error;
 395 }
 396
 397 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 398
 399 static int may_context_mount_sb_relabel(u32 sid,
 400                         struct superblock_security_struct *sbsec,
 401                         const struct cred *cred)
 402 {
 403         const struct task_security_struct *tsec = selinux_cred(cred);
 404         int rc;
 405
 406         rc = avc_has_perm(&selinux_state,
 407                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 408                           FILESYSTEM__RELABELFROM, NULL);
 409         if (rc)
 410                 return rc;
 411
 412         rc = avc_has_perm(&selinux_state,
 413                           tsec->sid, sid, SECCLASS_FILESYSTEM,
 414                           FILESYSTEM__RELABELTO, NULL);
 415         return rc;
 416 }
 417
 418 static int may_context_mount_inode_relabel(u32 sid,
 419                         struct superblock_security_struct *sbsec,
 420                         const struct cred *cred)
 421 {
 422         const struct task_security_struct *tsec = selinux_cred(cred);
 423         int rc;
 424         rc = avc_has_perm(&selinux_state,
 425                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 426                           FILESYSTEM__RELABELFROM, NULL);
 427         if (rc)
 428                 return rc;
 429
 430         rc = avc_has_perm(&selinux_state,
 431                           sid, sbsec->sid, SECCLASS_FILESYSTEM,
 432                           FILESYSTEM__ASSOCIATE, NULL);
 433         return rc;
 434 }
 435
 436 static int selinux_is_genfs_special_handling(struct super_block *sb)
 437 {
 438         /* Special handling. Genfs but also in-core setxattr handler */
 439         return  !strcmp(sb->s_type->name, "sysfs") ||
 440                 !strcmp(sb->s_type->name, "pstore") ||
 441                 !strcmp(sb->s_type->name, "debugfs") ||
 442                 !strcmp(sb->s_type->name, "tracefs") ||
 443                 !strcmp(sb->s_type->name, "rootfs") ||
 444                 (selinux_policycap_cgroupseclabel() &&
 445                  (!strcmp(sb->s_type->name, "cgroup") ||
 446                   !strcmp(sb->s_type->name, "cgroup2")));
 447 }
 448
 449 static int selinux_is_sblabel_mnt(struct super_block *sb)
 450 {
 451         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 452
 453         /*
 454          * IMPORTANT: Double-check logic in this function when adding a new
 455          * SECURITY_FS_USE_* definition!
 456          */
 457         BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
 458
 459         switch (sbsec->behavior) {
 460         case SECURITY_FS_USE_XATTR:
 461         case SECURITY_FS_USE_TRANS:
 462         case SECURITY_FS_USE_TASK:
 463         case SECURITY_FS_USE_NATIVE:
 464                 return 1;
 465
 466         case SECURITY_FS_USE_GENFS:
 467                 return selinux_is_genfs_special_handling(sb);
 468
 469         /* Never allow relabeling on context mounts */
 470         case SECURITY_FS_USE_MNTPOINT:
 471         case SECURITY_FS_USE_NONE:
 472         default:
 473                 return 0;
 474         }
 475 }
 476
 477 static int sb_check_xattr_support(struct super_block *sb)
 478 {
 479         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 480         struct dentry *root = sb->s_root;
 481         struct inode *root_inode = d_backing_inode(root);
 482         u32 sid;
 483         int rc;
 484
 485         /*
 486          * Make sure that the xattr handler exists and that no
 487          * error other than -ENODATA is returned by getxattr on
 488          * the root directory.  -ENODATA is ok, as this may be
 489          * the first boot of the SELinux kernel before we have
 490          * assigned xattr values to the filesystem.
 491          */
 492         if (!(root_inode->i_opflags & IOP_XATTR)) {
 493                 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
 494                         sb->s_id, sb->s_type->name);
 495                 goto fallback;
 496         }
 497
 498         rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 499         if (rc < 0 && rc != -ENODATA) {
 500                 if (rc == -EOPNOTSUPP) {
 501                         pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
 502                                 sb->s_id, sb->s_type->name);
 503                         goto fallback;
 504                 } else {
 505                         pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
 506                                 sb->s_id, sb->s_type->name, -rc);
 507                         return rc;
 508                 }
 509         }
 510         return 0;
 511
 512 fallback:
 513         /* No xattr support - try to fallback to genfs if possible. */
 514         rc = security_genfs_sid(&selinux_state, sb->s_type->name, "/",
 515                                 SECCLASS_DIR, &sid);
 516         if (rc)
 517                 return -EOPNOTSUPP;
 518
 519         pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
 520                 sb->s_id, sb->s_type->name);
 521         sbsec->behavior = SECURITY_FS_USE_GENFS;
 522         sbsec->sid = sid;
 523         return 0;
 524 }
 525
 526 static int sb_finish_set_opts(struct super_block *sb)
 527 {
 528         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 529         struct dentry *root = sb->s_root;
 530         struct inode *root_inode = d_backing_inode(root);
 531         int rc = 0;
 532
 533         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 534                 rc = sb_check_xattr_support(sb);
 535                 if (rc)
 536                         return rc;
 537         }
 538
 539         sbsec->flags |= SE_SBINITIALIZED;
 540
 541         /*
 542          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 543          * leave the flag untouched because sb_clone_mnt_opts might be handing
 544          * us a superblock that needs the flag to be cleared.
 545          */
 546         if (selinux_is_sblabel_mnt(sb))
 547                 sbsec->flags |= SBLABEL_MNT;
 548         else
 549                 sbsec->flags &= ~SBLABEL_MNT;
 550
 551         /* Initialize the root inode. */
 552         rc = inode_doinit_with_dentry(root_inode, root);
 553
 554         /* Initialize any other inodes associated with the superblock, e.g.
 555            inodes created prior to initial policy load or inodes created
 556            during get_sb by a pseudo filesystem that directly
 557            populates itself. */
 558         spin_lock(&sbsec->isec_lock);
 559         while (!list_empty(&sbsec->isec_head)) {
 560                 struct inode_security_struct *isec =
 561                                 list_first_entry(&sbsec->isec_head,
 562                                            struct inode_security_struct, list);
 563                 struct inode *inode = isec->inode;
 564                 list_del_init(&isec->list);
 565                 spin_unlock(&sbsec->isec_lock);
 566                 inode = igrab(inode);
 567                 if (inode) {
 568                         if (!IS_PRIVATE(inode))
 569                                 inode_doinit_with_dentry(inode, NULL);
 570                         iput(inode);
 571                 }
 572                 spin_lock(&sbsec->isec_lock);
 573         }
 574         spin_unlock(&sbsec->isec_lock);
 575         return rc;
 576 }
 577
 578 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 579                       u32 old_sid, u32 new_sid)
 580 {
 581         char mnt_flags = sbsec->flags & SE_MNTMASK;
 582
 583         /* check if the old mount command had the same options */
 584         if (sbsec->flags & SE_SBINITIALIZED)
 585                 if (!(sbsec->flags & flag) ||
 586                     (old_sid != new_sid))
 587                         return 1;
 588
 589         /* check if we were passed the same options twice,
 590          * aka someone passed context=a,context=b
 591          */
 592         if (!(sbsec->flags & SE_SBINITIALIZED))
 593                 if (mnt_flags & flag)
 594                         return 1;
 595         return 0;
 596 }
 597
 598 /*
 599  * Allow filesystems with binary mount data to explicitly set mount point
 600  * labeling information.
 601  */
 602 static int selinux_set_mnt_opts(struct super_block *sb,
 603                                 void *mnt_opts,
 604                                 unsigned long kern_flags,
 605                                 unsigned long *set_kern_flags)
 606 {
 607         const struct cred *cred = current_cred();
 608         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 609         struct dentry *root = sb->s_root;
 610         struct selinux_mnt_opts *opts = mnt_opts;
 611         struct inode_security_struct *root_isec;
 612         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 613         u32 defcontext_sid = 0;
 614         int rc = 0;
 615
 616         mutex_lock(&sbsec->lock);
 617
 618         if (!selinux_initialized(&selinux_state)) {
 619                 if (!opts) {
 620                         /* Defer initialization until selinux_complete_init,
 621                            after the initial policy is loaded and the security
 622                            server is ready to handle calls. */
 623                         goto out;
 624                 }
 625                 rc = -EINVAL;
 626                 pr_warn("SELinux: Unable to set superblock options "
 627                         "before the security server is initialized\n");
 628                 goto out;
 629         }
 630         if (kern_flags && !set_kern_flags) {
 631                 /* Specifying internal flags without providing a place to
 632                  * place the results is not allowed */
 633                 rc = -EINVAL;
 634                 goto out;
 635         }
 636
 637         /*
 638          * Binary mount data FS will come through this function twice.  Once
 639          * from an explicit call and once from the generic calls from the vfs.
 640          * Since the generic VFS calls will not contain any security mount data
 641          * we need to skip the double mount verification.
 642          *
 643          * This does open a hole in which we will not notice if the first
 644          * mount using this sb set explicit options and a second mount using
 645          * this sb does not set any security options.  (The first options
 646          * will be used for both mounts)
 647          */
 648         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 649             && !opts)
 650                 goto out;
 651
 652         root_isec = backing_inode_security_novalidate(root);
 653
 654         /*
 655          * parse the mount options, check if they are valid sids.
 656          * also check if someone is trying to mount the same sb more
 657          * than once with different security options.
 658          */
 659         if (opts) {
 660                 if (opts->fscontext_sid) {
 661                         fscontext_sid = opts->fscontext_sid;
 662                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 663                                         fscontext_sid))
 664                                 goto out_double_mount;
 665                         sbsec->flags |= FSCONTEXT_MNT;
 666                 }
 667                 if (opts->context_sid) {
 668                         context_sid = opts->context_sid;
 669                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 670                                         context_sid))
 671                                 goto out_double_mount;
 672                         sbsec->flags |= CONTEXT_MNT;
 673                 }
 674                 if (opts->rootcontext_sid) {
 675                         rootcontext_sid = opts->rootcontext_sid;
 676                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 677                                         rootcontext_sid))
 678                                 goto out_double_mount;
 679                         sbsec->flags |= ROOTCONTEXT_MNT;
 680                 }
 681                 if (opts->defcontext_sid) {
 682                         defcontext_sid = opts->defcontext_sid;
 683                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 684                                         defcontext_sid))
 685                                 goto out_double_mount;
 686                         sbsec->flags |= DEFCONTEXT_MNT;
 687                 }
 688         }
 689
 690         if (sbsec->flags & SE_SBINITIALIZED) {
 691                 /* previously mounted with options, but not on this attempt? */
 692                 if ((sbsec->flags & SE_MNTMASK) && !opts)
 693                         goto out_double_mount;
 694                 rc = 0;
 695                 goto out;
 696         }
 697
 698         if (strcmp(sb->s_type->name, "proc") == 0)
 699                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 700
 701         if (!strcmp(sb->s_type->name, "debugfs") ||
 702             !strcmp(sb->s_type->name, "tracefs") ||
 703             !strcmp(sb->s_type->name, "binder") ||
 704             !strcmp(sb->s_type->name, "bpf") ||
 705             !strcmp(sb->s_type->name, "pstore") ||
 706             !strcmp(sb->s_type->name, "securityfs"))
 707                 sbsec->flags |= SE_SBGENFS;
 708
 709         if (!strcmp(sb->s_type->name, "sysfs") ||
 710             !strcmp(sb->s_type->name, "cgroup") ||
 711             !strcmp(sb->s_type->name, "cgroup2"))
 712                 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 713
 714         if (!sbsec->behavior) {
 715                 /*
 716                  * Determine the labeling behavior to use for this
 717                  * filesystem type.
 718                  */
 719                 rc = security_fs_use(&selinux_state, sb);
 720                 if (rc) {
 721                         pr_warn("%s: security_fs_use(%s) returned %d\n",
 722                                         __func__, sb->s_type->name, rc);
 723                         goto out;
 724                 }
 725         }
 726
 727         /*
 728          * If this is a user namespace mount and the filesystem type is not
 729          * explicitly whitelisted, then no contexts are allowed on the command
 730          * line and security labels must be ignored.
 731          */
 732         if (sb->s_user_ns != &init_user_ns &&
 733             strcmp(sb->s_type->name, "tmpfs") &&
 734             strcmp(sb->s_type->name, "ramfs") &&
 735             strcmp(sb->s_type->name, "devpts") &&
 736             strcmp(sb->s_type->name, "overlay")) {
 737                 if (context_sid || fscontext_sid || rootcontext_sid ||
 738                     defcontext_sid) {
 739                         rc = -EACCES;
 740                         goto out;
 741                 }
 742                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 743                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 744                         rc = security_transition_sid(&selinux_state,
 745                                                      current_sid(),
 746                                                      current_sid(),
 747                                                      SECCLASS_FILE, NULL,
 748                                                      &sbsec->mntpoint_sid);
 749                         if (rc)
 750                                 goto out;
 751                 }
 752                 goto out_set_opts;
 753         }
 754
 755         /* sets the context of the superblock for the fs being mounted. */
 756         if (fscontext_sid) {
 757                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 758                 if (rc)
 759                         goto out;
 760
 761                 sbsec->sid = fscontext_sid;
 762         }
 763
 764         /*
 765          * Switch to using mount point labeling behavior.
 766          * sets the label used on all file below the mountpoint, and will set
 767          * the superblock context if not already set.
 768          */
 769         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 770                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 771                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 772         }
 773
 774         if (context_sid) {
 775                 if (!fscontext_sid) {
 776                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 777                                                           cred);
 778                         if (rc)
 779                                 goto out;
 780                         sbsec->sid = context_sid;
 781                 } else {
 782                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 783                                                              cred);
 784                         if (rc)
 785                                 goto out;
 786                 }
 787                 if (!rootcontext_sid)
 788                         rootcontext_sid = context_sid;
 789
 790                 sbsec->mntpoint_sid = context_sid;
 791                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 792         }
 793
 794         if (rootcontext_sid) {
 795                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 796                                                      cred);
 797                 if (rc)
 798                         goto out;
 799
 800                 root_isec->sid = rootcontext_sid;
 801                 root_isec->initialized = LABEL_INITIALIZED;
 802         }
 803
 804         if (defcontext_sid) {
 805                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 806                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 807                         rc = -EINVAL;
 808                         pr_warn("SELinux: defcontext option is "
 809                                "invalid for this filesystem type\n");
 810                         goto out;
 811                 }
 812
 813                 if (defcontext_sid != sbsec->def_sid) {
 814                         rc = may_context_mount_inode_relabel(defcontext_sid,
 815                                                              sbsec, cred);
 816                         if (rc)
 817                                 goto out;
 818                 }
 819
 820                 sbsec->def_sid = defcontext_sid;
 821         }
 822
 823 out_set_opts:
 824         rc = sb_finish_set_opts(sb);
 825 out:
 826         mutex_unlock(&sbsec->lock);
 827         return rc;
 828 out_double_mount:
 829         rc = -EINVAL;
 830         pr_warn("SELinux: mount invalid.  Same superblock, different "
 831                "security settings for (dev %s, type %s)\n", sb->s_id,
 832                sb->s_type->name);
 833         goto out;
 834 }
 835
 836 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 837                                     const struct super_block *newsb)
 838 {
 839         struct superblock_security_struct *old = selinux_superblock(oldsb);
 840         struct superblock_security_struct *new = selinux_superblock(newsb);
 841         char oldflags = old->flags & SE_MNTMASK;
 842         char newflags = new->flags & SE_MNTMASK;
 843
 844         if (oldflags != newflags)
 845                 goto mismatch;
 846         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 847                 goto mismatch;
 848         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 849                 goto mismatch;
 850         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 851                 goto mismatch;
 852         if (oldflags & ROOTCONTEXT_MNT) {
 853                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 854                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 855                 if (oldroot->sid != newroot->sid)
 856                         goto mismatch;
 857         }
 858         return 0;
 859 mismatch:
 860         pr_warn("SELinux: mount invalid.  Same superblock, "
 861                             "different security settings for (dev %s, "
 862                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 863         return -EBUSY;
 864 }
 865
 866 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 867                                         struct super_block *newsb,
 868                                         unsigned long kern_flags,
 869                                         unsigned long *set_kern_flags)
 870 {
 871         int rc = 0;
 872         const struct superblock_security_struct *oldsbsec =
 873                                                 selinux_superblock(oldsb);
 874         struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
 875
 876         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 877         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 878         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 879
 880         /*
 881          * if the parent was able to be mounted it clearly had no special lsm
 882          * mount options.  thus we can safely deal with this superblock later
 883          */
 884         if (!selinux_initialized(&selinux_state))
 885                 return 0;
 886
 887         /*
 888          * Specifying internal flags without providing a place to
 889          * place the results is not allowed.
 890          */
 891         if (kern_flags && !set_kern_flags)
 892                 return -EINVAL;
 893
 894         /* how can we clone if the old one wasn't set up?? */
 895         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 896
 897         /* if fs is reusing a sb, make sure that the contexts match */
 898         if (newsbsec->flags & SE_SBINITIALIZED) {
 899                 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
 900                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 901                 return selinux_cmp_sb_context(oldsb, newsb);
 902         }
 903
 904         mutex_lock(&newsbsec->lock);
 905
 906         newsbsec->flags = oldsbsec->flags;
 907
 908         newsbsec->sid = oldsbsec->sid;
 909         newsbsec->def_sid = oldsbsec->def_sid;
 910         newsbsec->behavior = oldsbsec->behavior;
 911
 912         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
 913                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
 914                 rc = security_fs_use(&selinux_state, newsb);
 915                 if (rc)
 916                         goto out;
 917         }
 918
 919         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
 920                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
 921                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 922         }
 923
 924         if (set_context) {
 925                 u32 sid = oldsbsec->mntpoint_sid;
 926
 927                 if (!set_fscontext)
 928                         newsbsec->sid = sid;
 929                 if (!set_rootcontext) {
 930                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 931                         newisec->sid = sid;
 932                 }
 933                 newsbsec->mntpoint_sid = sid;
 934         }
 935         if (set_rootcontext) {
 936                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
 937                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 938
 939                 newisec->sid = oldisec->sid;
 940         }
 941
 942         sb_finish_set_opts(newsb);
 943 out:
 944         mutex_unlock(&newsbsec->lock);
 945         return rc;
 946 }
 947
 948 /*
 949  * NOTE: the caller is resposible for freeing the memory even if on error.
 950  */
 951 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 952 {
 953         struct selinux_mnt_opts *opts = *mnt_opts;
 954         u32 *dst_sid;
 955         int rc;
 956
 957         if (token == Opt_seclabel)
 958                 /* eaten and completely ignored */
 959                 return 0;
 960         if (!s)
 961                 return -EINVAL;
 962
 963         if (!selinux_initialized(&selinux_state)) {
 964                 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
 965                 return -EINVAL;
 966         }
 967
 968         if (!opts) {
 969                 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 970                 if (!opts)
 971                         return -ENOMEM;
 972                 *mnt_opts = opts;
 973         }
 974
 975         switch (token) {
 976         case Opt_context:
 977                 if (opts->context_sid || opts->defcontext_sid)
 978                         goto err;
 979                 dst_sid = &opts->context_sid;
 980                 break;
 981         case Opt_fscontext:
 982                 if (opts->fscontext_sid)
 983                         goto err;
 984                 dst_sid = &opts->fscontext_sid;
 985                 break;
 986         case Opt_rootcontext:
 987                 if (opts->rootcontext_sid)
 988                         goto err;
 989                 dst_sid = &opts->rootcontext_sid;
 990                 break;
 991         case Opt_defcontext:
 992                 if (opts->context_sid || opts->defcontext_sid)
 993                         goto err;
 994                 dst_sid = &opts->defcontext_sid;
 995                 break;
 996         default:
 997                 WARN_ON(1);
 998                 return -EINVAL;
 999         }
1000         rc = security_context_str_to_sid(&selinux_state, s, dst_sid, GFP_KERNEL);
1001         if (rc)
1002                 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1003                         s, rc);
1004         return rc;
1005
1006 err:
1007         pr_warn(SEL_MOUNT_FAIL_MSG);
1008         return -EINVAL;
1009 }
1010
1011 static int show_sid(struct seq_file *m, u32 sid)
1012 {
1013         char *context = NULL;
1014         u32 len;
1015         int rc;
1016
1017         rc = security_sid_to_context(&selinux_state, sid,
1018                                              &context, &len);
1019         if (!rc) {
1020                 bool has_comma = strchr(context, ',');
1021
1022                 seq_putc(m, '=');
1023                 if (has_comma)
1024                         seq_putc(m, '\"');
1025                 seq_escape(m, context, "\"\n\\");
1026                 if (has_comma)
1027                         seq_putc(m, '\"');
1028         }
1029         kfree(context);
1030         return rc;
1031 }
1032
1033 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1034 {
1035         struct superblock_security_struct *sbsec = selinux_superblock(sb);
1036         int rc;
1037
1038         if (!(sbsec->flags & SE_SBINITIALIZED))
1039                 return 0;
1040
1041         if (!selinux_initialized(&selinux_state))
1042                 return 0;
1043
1044         if (sbsec->flags & FSCONTEXT_MNT) {
1045                 seq_putc(m, ',');
1046                 seq_puts(m, FSCONTEXT_STR);
1047                 rc = show_sid(m, sbsec->sid);
1048                 if (rc)
1049                         return rc;
1050         }
1051         if (sbsec->flags & CONTEXT_MNT) {
1052                 seq_putc(m, ',');
1053                 seq_puts(m, CONTEXT_STR);
1054                 rc = show_sid(m, sbsec->mntpoint_sid);
1055                 if (rc)
1056                         return rc;
1057         }
1058         if (sbsec->flags & DEFCONTEXT_MNT) {
1059                 seq_putc(m, ',');
1060                 seq_puts(m, DEFCONTEXT_STR);
1061                 rc = show_sid(m, sbsec->def_sid);
1062                 if (rc)
1063                         return rc;
1064         }
1065         if (sbsec->flags & ROOTCONTEXT_MNT) {
1066                 struct dentry *root = sb->s_root;
1067                 struct inode_security_struct *isec = backing_inode_security(root);
1068                 seq_putc(m, ',');
1069                 seq_puts(m, ROOTCONTEXT_STR);
1070                 rc = show_sid(m, isec->sid);
1071                 if (rc)
1072                         return rc;
1073         }
1074         if (sbsec->flags & SBLABEL_MNT) {
1075                 seq_putc(m, ',');
1076                 seq_puts(m, SECLABEL_STR);
1077         }
1078         return 0;
1079 }
1080
1081 static inline u16 inode_mode_to_security_class(umode_t mode)
1082 {
1083         switch (mode & S_IFMT) {
1084         case S_IFSOCK:
1085                 return SECCLASS_SOCK_FILE;
1086         case S_IFLNK:
1087                 return SECCLASS_LNK_FILE;
1088         case S_IFREG:
1089                 return SECCLASS_FILE;
1090         case S_IFBLK:
1091                 return SECCLASS_BLK_FILE;
1092         case S_IFDIR:
1093                 return SECCLASS_DIR;
1094         case S_IFCHR:
1095                 return SECCLASS_CHR_FILE;
1096         case S_IFIFO:
1097                 return SECCLASS_FIFO_FILE;
1098
1099         }
1100
1101         return SECCLASS_FILE;
1102 }
1103
1104 static inline int default_protocol_stream(int protocol)
1105 {
1106         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1107                 protocol == IPPROTO_MPTCP);
1108 }
1109
1110 static inline int default_protocol_dgram(int protocol)
1111 {
1112         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1113 }
1114
1115 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1116 {
1117         int extsockclass = selinux_policycap_extsockclass();
1118
1119         switch (family) {
1120         case PF_UNIX:
1121                 switch (type) {
1122                 case SOCK_STREAM:
1123                 case SOCK_SEQPACKET:
1124                         return SECCLASS_UNIX_STREAM_SOCKET;
1125                 case SOCK_DGRAM:
1126                 case SOCK_RAW:
1127                         return SECCLASS_UNIX_DGRAM_SOCKET;
1128                 }
1129                 break;
1130         case PF_INET:
1131         case PF_INET6:
1132                 switch (type) {
1133                 case SOCK_STREAM:
1134                 case SOCK_SEQPACKET:
1135                         if (default_protocol_stream(protocol))
1136                                 return SECCLASS_TCP_SOCKET;
1137                         else if (extsockclass && protocol == IPPROTO_SCTP)
1138                                 return SECCLASS_SCTP_SOCKET;
1139                         else
1140                                 return SECCLASS_RAWIP_SOCKET;
1141                 case SOCK_DGRAM:
1142                         if (default_protocol_dgram(protocol))
1143                                 return SECCLASS_UDP_SOCKET;
1144                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1145                                                   protocol == IPPROTO_ICMPV6))
1146                                 return SECCLASS_ICMP_SOCKET;
1147                         else
1148                                 return SECCLASS_RAWIP_SOCKET;
1149                 case SOCK_DCCP:
1150                         return SECCLASS_DCCP_SOCKET;
1151                 default:
1152                         return SECCLASS_RAWIP_SOCKET;
1153                 }
1154                 break;
1155         case PF_NETLINK:
1156                 switch (protocol) {
1157                 case NETLINK_ROUTE:
1158                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1159                 case NETLINK_SOCK_DIAG:
1160                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1161                 case NETLINK_NFLOG:
1162                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1163                 case NETLINK_XFRM:
1164                         return SECCLASS_NETLINK_XFRM_SOCKET;
1165                 case NETLINK_SELINUX:
1166                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1167                 case NETLINK_ISCSI:
1168                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1169                 case NETLINK_AUDIT:
1170                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1171                 case NETLINK_FIB_LOOKUP:
1172                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1173                 case NETLINK_CONNECTOR:
1174                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1175                 case NETLINK_NETFILTER:
1176                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1177                 case NETLINK_DNRTMSG:
1178                         return SECCLASS_NETLINK_DNRT_SOCKET;
1179                 case NETLINK_KOBJECT_UEVENT:
1180                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1181                 case NETLINK_GENERIC:
1182                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1183                 case NETLINK_SCSITRANSPORT:
1184                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1185                 case NETLINK_RDMA:
1186                         return SECCLASS_NETLINK_RDMA_SOCKET;
1187                 case NETLINK_CRYPTO:
1188                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1189                 default:
1190                         return SECCLASS_NETLINK_SOCKET;
1191                 }
1192         case PF_PACKET:
1193                 return SECCLASS_PACKET_SOCKET;
1194         case PF_KEY:
1195                 return SECCLASS_KEY_SOCKET;
1196         case PF_APPLETALK:
1197                 return SECCLASS_APPLETALK_SOCKET;
1198         }
1199
1200         if (extsockclass) {
1201                 switch (family) {
1202                 case PF_AX25:
1203                         return SECCLASS_AX25_SOCKET;
1204                 case PF_IPX:
1205                         return SECCLASS_IPX_SOCKET;
1206                 case PF_NETROM:
1207                         return SECCLASS_NETROM_SOCKET;
1208                 case PF_ATMPVC:
1209                         return SECCLASS_ATMPVC_SOCKET;
1210                 case PF_X25:
1211                         return SECCLASS_X25_SOCKET;
1212                 case PF_ROSE:
1213                         return SECCLASS_ROSE_SOCKET;
1214                 case PF_DECnet:
1215                         return SECCLASS_DECNET_SOCKET;
1216                 case PF_ATMSVC:
1217                         return SECCLASS_ATMSVC_SOCKET;
1218                 case PF_RDS:
1219                         return SECCLASS_RDS_SOCKET;
1220                 case PF_IRDA:
1221                         return SECCLASS_IRDA_SOCKET;
1222                 case PF_PPPOX:
1223                         return SECCLASS_PPPOX_SOCKET;
1224                 case PF_LLC:
1225                         return SECCLASS_LLC_SOCKET;
1226                 case PF_CAN:
1227                         return SECCLASS_CAN_SOCKET;
1228                 case PF_TIPC:
1229                         return SECCLASS_TIPC_SOCKET;
1230                 case PF_BLUETOOTH:
1231                         return SECCLASS_BLUETOOTH_SOCKET;
1232                 case PF_IUCV:
1233                         return SECCLASS_IUCV_SOCKET;
1234                 case PF_RXRPC:
1235                         return SECCLASS_RXRPC_SOCKET;
1236                 case PF_ISDN:
1237                         return SECCLASS_ISDN_SOCKET;
1238                 case PF_PHONET:
1239                         return SECCLASS_PHONET_SOCKET;
1240                 case PF_IEEE802154:
1241                         return SECCLASS_IEEE802154_SOCKET;
1242                 case PF_CAIF:
1243                         return SECCLASS_CAIF_SOCKET;
1244                 case PF_ALG:
1245                         return SECCLASS_ALG_SOCKET;
1246                 case PF_NFC:
1247                         return SECCLASS_NFC_SOCKET;
1248                 case PF_VSOCK:
1249                         return SECCLASS_VSOCK_SOCKET;
1250                 case PF_KCM:
1251                         return SECCLASS_KCM_SOCKET;
1252                 case PF_QIPCRTR:
1253                         return SECCLASS_QIPCRTR_SOCKET;
1254                 case PF_SMC:
1255                         return SECCLASS_SMC_SOCKET;
1256                 case PF_XDP:
1257                         return SECCLASS_XDP_SOCKET;
1258                 case PF_MCTP:
1259                         return SECCLASS_MCTP_SOCKET;
1260 #if PF_MAX > 46
1261 #error New address family defined, please update this function.
1262 #endif
1263                 }
1264         }
1265
1266         return SECCLASS_SOCKET;
1267 }
1268
1269 static int selinux_genfs_get_sid(struct dentry *dentry,
1270                                  u16 tclass,
1271                                  u16 flags,
1272                                  u32 *sid)
1273 {
1274         int rc;
1275         struct super_block *sb = dentry->d_sb;
1276         char *buffer, *path;
1277
1278         buffer = (char *)__get_free_page(GFP_KERNEL);
1279         if (!buffer)
1280                 return -ENOMEM;
1281
1282         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1283         if (IS_ERR(path))
1284                 rc = PTR_ERR(path);
1285         else {
1286                 if (flags & SE_SBPROC) {
1287                         /* each process gets a /proc/PID/ entry. Strip off the
1288                          * PID part to get a valid selinux labeling.
1289                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1290                         while (path[1] >= '0' && path[1] <= '9') {
1291                                 path[1] = '/';
1292                                 path++;
1293                         }
1294                 }
1295                 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1296                                         path, tclass, sid);
1297                 if (rc == -ENOENT) {
1298                         /* No match in policy, mark as unlabeled. */
1299                         *sid = SECINITSID_UNLABELED;
1300                         rc = 0;
1301                 }
1302         }
1303         free_page((unsigned long)buffer);
1304         return rc;
1305 }
1306
1307 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1308                                   u32 def_sid, u32 *sid)
1309 {
1310 #define INITCONTEXTLEN 255
1311         char *context;
1312         unsigned int len;
1313         int rc;
1314
1315         len = INITCONTEXTLEN;
1316         context = kmalloc(len + 1, GFP_NOFS);
1317         if (!context)
1318                 return -ENOMEM;
1319
1320         context[len] = '\0';
1321         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1322         if (rc == -ERANGE) {
1323                 kfree(context);
1324
1325                 /* Need a larger buffer.  Query for the right size. */
1326                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1327                 if (rc < 0)
1328                         return rc;
1329
1330                 len = rc;
1331                 context = kmalloc(len + 1, GFP_NOFS);
1332                 if (!context)
1333                         return -ENOMEM;
1334
1335                 context[len] = '\0';
1336                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1337                                     context, len);
1338         }
1339         if (rc < 0) {
1340                 kfree(context);
1341                 if (rc != -ENODATA) {
1342                         pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1343                                 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1344                         return rc;
1345                 }
1346                 *sid = def_sid;
1347                 return 0;
1348         }
1349
1350         rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1351                                              def_sid, GFP_NOFS);
1352         if (rc) {
1353                 char *dev = inode->i_sb->s_id;
1354                 unsigned long ino = inode->i_ino;
1355
1356                 if (rc == -EINVAL) {
1357                         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",
1358                                               ino, dev, context);
1359                 } else {
1360                         pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1361                                 __func__, context, -rc, dev, ino);
1362                 }
1363         }
1364         kfree(context);
1365         return 0;
1366 }
1367
1368 /* The inode's security attributes must be initialized before first use. */
1369 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1370 {
1371         struct superblock_security_struct *sbsec = NULL;
1372         struct inode_security_struct *isec = selinux_inode(inode);
1373         u32 task_sid, sid = 0;
1374         u16 sclass;
1375         struct dentry *dentry;
1376         int rc = 0;
1377
1378         if (isec->initialized == LABEL_INITIALIZED)
1379                 return 0;
1380
1381         spin_lock(&isec->lock);
1382         if (isec->initialized == LABEL_INITIALIZED)
1383                 goto out_unlock;
1384
1385         if (isec->sclass == SECCLASS_FILE)
1386                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1387
1388         sbsec = selinux_superblock(inode->i_sb);
1389         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1390                 /* Defer initialization until selinux_complete_init,
1391                    after the initial policy is loaded and the security
1392                    server is ready to handle calls. */
1393                 spin_lock(&sbsec->isec_lock);
1394                 if (list_empty(&isec->list))
1395                         list_add(&isec->list, &sbsec->isec_head);
1396                 spin_unlock(&sbsec->isec_lock);
1397                 goto out_unlock;
1398         }
1399
1400         sclass = isec->sclass;
1401         task_sid = isec->task_sid;
1402         sid = isec->sid;
1403         isec->initialized = LABEL_PENDING;
1404         spin_unlock(&isec->lock);
1405
1406         switch (sbsec->behavior) {
1407         case SECURITY_FS_USE_NATIVE:
1408                 break;
1409         case SECURITY_FS_USE_XATTR:
1410                 if (!(inode->i_opflags & IOP_XATTR)) {
1411                         sid = sbsec->def_sid;
1412                         break;
1413                 }
1414                 /* Need a dentry, since the xattr API requires one.
1415                    Life would be simpler if we could just pass the inode. */
1416                 if (opt_dentry) {
1417                         /* Called from d_instantiate or d_splice_alias. */
1418                         dentry = dget(opt_dentry);
1419                 } else {
1420                         /*
1421                          * Called from selinux_complete_init, try to find a dentry.
1422                          * Some filesystems really want a connected one, so try
1423                          * that first.  We could split SECURITY_FS_USE_XATTR in
1424                          * two, depending upon that...
1425                          */
1426                         dentry = d_find_alias(inode);
1427                         if (!dentry)
1428                                 dentry = d_find_any_alias(inode);
1429                 }
1430                 if (!dentry) {
1431                         /*
1432                          * this is can be hit on boot when a file is accessed
1433                          * before the policy is loaded.  When we load policy we
1434                          * may find inodes that have no dentry on the
1435                          * sbsec->isec_head list.  No reason to complain as these
1436                          * will get fixed up the next time we go through
1437                          * inode_doinit with a dentry, before these inodes could
1438                          * be used again by userspace.
1439                          */
1440                         goto out_invalid;
1441                 }
1442
1443                 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1444                                             &sid);
1445                 dput(dentry);
1446                 if (rc)
1447                         goto out;
1448                 break;
1449         case SECURITY_FS_USE_TASK:
1450                 sid = task_sid;
1451                 break;
1452         case SECURITY_FS_USE_TRANS:
1453                 /* Default to the fs SID. */
1454                 sid = sbsec->sid;
1455
1456                 /* Try to obtain a transition SID. */
1457                 rc = security_transition_sid(&selinux_state, task_sid, sid,
1458                                              sclass, NULL, &sid);
1459                 if (rc)
1460                         goto out;
1461                 break;
1462         case SECURITY_FS_USE_MNTPOINT:
1463                 sid = sbsec->mntpoint_sid;
1464                 break;
1465         default:
1466                 /* Default to the fs superblock SID. */
1467                 sid = sbsec->sid;
1468
1469                 if ((sbsec->flags & SE_SBGENFS) &&
1470                      (!S_ISLNK(inode->i_mode) ||
1471                       selinux_policycap_genfs_seclabel_symlinks())) {
1472                         /* We must have a dentry to determine the label on
1473                          * procfs inodes */
1474                         if (opt_dentry) {
1475                                 /* Called from d_instantiate or
1476                                  * d_splice_alias. */
1477                                 dentry = dget(opt_dentry);
1478                         } else {
1479                                 /* Called from selinux_complete_init, try to
1480                                  * find a dentry.  Some filesystems really want
1481                                  * a connected one, so try that first.
1482                                  */
1483                                 dentry = d_find_alias(inode);
1484                                 if (!dentry)
1485                                         dentry = d_find_any_alias(inode);
1486                         }
1487                         /*
1488                          * This can be hit on boot when a file is accessed
1489                          * before the policy is loaded.  When we load policy we
1490                          * may find inodes that have no dentry on the
1491                          * sbsec->isec_head list.  No reason to complain as
1492                          * these will get fixed up the next time we go through
1493                          * inode_doinit() with a dentry, before these inodes
1494                          * could be used again by userspace.
1495                          */
1496                         if (!dentry)
1497                                 goto out_invalid;
1498                         rc = selinux_genfs_get_sid(dentry, sclass,
1499                                                    sbsec->flags, &sid);
1500                         if (rc) {
1501                                 dput(dentry);
1502                                 goto out;
1503                         }
1504
1505                         if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1506                             (inode->i_opflags & IOP_XATTR)) {
1507                                 rc = inode_doinit_use_xattr(inode, dentry,
1508                                                             sid, &sid);
1509                                 if (rc) {
1510                                         dput(dentry);
1511                                         goto out;
1512                                 }
1513                         }
1514                         dput(dentry);
1515                 }
1516                 break;
1517         }
1518
1519 out:
1520         spin_lock(&isec->lock);
1521         if (isec->initialized == LABEL_PENDING) {
1522                 if (rc) {
1523                         isec->initialized = LABEL_INVALID;
1524                         goto out_unlock;
1525                 }
1526                 isec->initialized = LABEL_INITIALIZED;
1527                 isec->sid = sid;
1528         }
1529
1530 out_unlock:
1531         spin_unlock(&isec->lock);
1532         return rc;
1533
1534 out_invalid:
1535         spin_lock(&isec->lock);
1536         if (isec->initialized == LABEL_PENDING) {
1537                 isec->initialized = LABEL_INVALID;
1538                 isec->sid = sid;
1539         }
1540         spin_unlock(&isec->lock);
1541         return 0;
1542 }
1543
1544 /* Convert a Linux signal to an access vector. */
1545 static inline u32 signal_to_av(int sig)
1546 {
1547         u32 perm = 0;
1548
1549         switch (sig) {
1550         case SIGCHLD:
1551                 /* Commonly granted from child to parent. */
1552                 perm = PROCESS__SIGCHLD;
1553                 break;
1554         case SIGKILL:
1555                 /* Cannot be caught or ignored */
1556                 perm = PROCESS__SIGKILL;
1557                 break;
1558         case SIGSTOP:
1559                 /* Cannot be caught or ignored */
1560                 perm = PROCESS__SIGSTOP;
1561                 break;
1562         default:
1563                 /* All other signals. */
1564                 perm = PROCESS__SIGNAL;
1565                 break;
1566         }
1567
1568         return perm;
1569 }
1570
1571 #if CAP_LAST_CAP > 63
1572 #error Fix SELinux to handle capabilities > 63.
1573 #endif
1574
1575 /* Check whether a task is allowed to use a capability. */
1576 static int cred_has_capability(const struct cred *cred,
1577                                int cap, unsigned int opts, bool initns)
1578 {
1579         struct common_audit_data ad;
1580         struct av_decision avd;
1581         u16 sclass;
1582         u32 sid = cred_sid(cred);
1583         u32 av = CAP_TO_MASK(cap);
1584         int rc;
1585
1586         ad.type = LSM_AUDIT_DATA_CAP;
1587         ad.u.cap = cap;
1588
1589         switch (CAP_TO_INDEX(cap)) {
1590         case 0:
1591                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1592                 break;
1593         case 1:
1594                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1595                 break;
1596         default:
1597                 pr_err("SELinux:  out of range capability %d\n", cap);
1598                 BUG();
1599                 return -EINVAL;
1600         }
1601
1602         rc = avc_has_perm_noaudit(&selinux_state,
1603                                   sid, sid, sclass, av, 0, &avd);
1604         if (!(opts & CAP_OPT_NOAUDIT)) {
1605                 int rc2 = avc_audit(&selinux_state,
1606                                     sid, sid, sclass, av, &avd, rc, &ad);
1607                 if (rc2)
1608                         return rc2;
1609         }
1610         return rc;
1611 }
1612
1613 /* Check whether a task has a particular permission to an inode.
1614    The 'adp' parameter is optional and allows other audit
1615    data to be passed (e.g. the dentry). */
1616 static int inode_has_perm(const struct cred *cred,
1617                           struct inode *inode,
1618                           u32 perms,
1619                           struct common_audit_data *adp)
1620 {
1621         struct inode_security_struct *isec;
1622         u32 sid;
1623
1624         validate_creds(cred);
1625
1626         if (unlikely(IS_PRIVATE(inode)))
1627                 return 0;
1628
1629         sid = cred_sid(cred);
1630         isec = selinux_inode(inode);
1631
1632         return avc_has_perm(&selinux_state,
1633                             sid, isec->sid, isec->sclass, perms, adp);
1634 }
1635
1636 /* Same as inode_has_perm, but pass explicit audit data containing
1637    the dentry to help the auditing code to more easily generate the
1638    pathname if needed. */
1639 static inline int dentry_has_perm(const struct cred *cred,
1640                                   struct dentry *dentry,
1641                                   u32 av)
1642 {
1643         struct inode *inode = d_backing_inode(dentry);
1644         struct common_audit_data ad;
1645
1646         ad.type = LSM_AUDIT_DATA_DENTRY;
1647         ad.u.dentry = dentry;
1648         __inode_security_revalidate(inode, dentry, true);
1649         return inode_has_perm(cred, inode, av, &ad);
1650 }
1651
1652 /* Same as inode_has_perm, but pass explicit audit data containing
1653    the path to help the auditing code to more easily generate the
1654    pathname if needed. */
1655 static inline int path_has_perm(const struct cred *cred,
1656                                 const struct path *path,
1657                                 u32 av)
1658 {
1659         struct inode *inode = d_backing_inode(path->dentry);
1660         struct common_audit_data ad;
1661
1662         ad.type = LSM_AUDIT_DATA_PATH;
1663         ad.u.path = *path;
1664         __inode_security_revalidate(inode, path->dentry, true);
1665         return inode_has_perm(cred, inode, av, &ad);
1666 }
1667
1668 /* Same as path_has_perm, but uses the inode from the file struct. */
1669 static inline int file_path_has_perm(const struct cred *cred,
1670                                      struct file *file,
1671                                      u32 av)
1672 {
1673         struct common_audit_data ad;
1674
1675         ad.type = LSM_AUDIT_DATA_FILE;
1676         ad.u.file = file;
1677         return inode_has_perm(cred, file_inode(file), av, &ad);
1678 }
1679
1680 #ifdef CONFIG_BPF_SYSCALL
1681 static int bpf_fd_pass(struct file *file, u32 sid);
1682 #endif
1683
1684 /* Check whether a task can use an open file descriptor to
1685    access an inode in a given way.  Check access to the
1686    descriptor itself, and then use dentry_has_perm to
1687    check a particular permission to the file.
1688    Access to the descriptor is implicitly granted if it
1689    has the same SID as the process.  If av is zero, then
1690    access to the file is not checked, e.g. for cases
1691    where only the descriptor is affected like seek. */
1692 static int file_has_perm(const struct cred *cred,
1693                          struct file *file,
1694                          u32 av)
1695 {
1696         struct file_security_struct *fsec = selinux_file(file);
1697         struct inode *inode = file_inode(file);
1698         struct common_audit_data ad;
1699         u32 sid = cred_sid(cred);
1700         int rc;
1701
1702         ad.type = LSM_AUDIT_DATA_FILE;
1703         ad.u.file = file;
1704
1705         if (sid != fsec->sid) {
1706                 rc = avc_has_perm(&selinux_state,
1707                                   sid, fsec->sid,
1708                                   SECCLASS_FD,
1709                                   FD__USE,
1710                                   &ad);
1711                 if (rc)
1712                         goto out;
1713         }
1714
1715 #ifdef CONFIG_BPF_SYSCALL
1716         rc = bpf_fd_pass(file, cred_sid(cred));
1717         if (rc)
1718                 return rc;
1719 #endif
1720
1721         /* av is zero if only checking access to the descriptor. */
1722         rc = 0;
1723         if (av)
1724                 rc = inode_has_perm(cred, inode, av, &ad);
1725
1726 out:
1727         return rc;
1728 }
1729
1730 /*
1731  * Determine the label for an inode that might be unioned.
1732  */
1733 static int
1734 selinux_determine_inode_label(const struct task_security_struct *tsec,
1735                                  struct inode *dir,
1736                                  const struct qstr *name, u16 tclass,
1737                                  u32 *_new_isid)
1738 {
1739         const struct superblock_security_struct *sbsec =
1740                                                 selinux_superblock(dir->i_sb);
1741
1742         if ((sbsec->flags & SE_SBINITIALIZED) &&
1743             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1744                 *_new_isid = sbsec->mntpoint_sid;
1745         } else if ((sbsec->flags & SBLABEL_MNT) &&
1746                    tsec->create_sid) {
1747                 *_new_isid = tsec->create_sid;
1748         } else {
1749                 const struct inode_security_struct *dsec = inode_security(dir);
1750                 return security_transition_sid(&selinux_state, tsec->sid,
1751                                                dsec->sid, tclass,
1752                                                name, _new_isid);
1753         }
1754
1755         return 0;
1756 }
1757
1758 /* Check whether a task can create a file. */
1759 static int may_create(struct inode *dir,
1760                       struct dentry *dentry,
1761                       u16 tclass)
1762 {
1763         const struct task_security_struct *tsec = selinux_cred(current_cred());
1764         struct inode_security_struct *dsec;
1765         struct superblock_security_struct *sbsec;
1766         u32 sid, newsid;
1767         struct common_audit_data ad;
1768         int rc;
1769
1770         dsec = inode_security(dir);
1771         sbsec = selinux_superblock(dir->i_sb);
1772
1773         sid = tsec->sid;
1774
1775         ad.type = LSM_AUDIT_DATA_DENTRY;
1776         ad.u.dentry = dentry;
1777
1778         rc = avc_has_perm(&selinux_state,
1779                           sid, dsec->sid, SECCLASS_DIR,
1780                           DIR__ADD_NAME | DIR__SEARCH,
1781                           &ad);
1782         if (rc)
1783                 return rc;
1784
1785         rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1786                                            &newsid);
1787         if (rc)
1788                 return rc;
1789
1790         rc = avc_has_perm(&selinux_state,
1791                           sid, newsid, tclass, FILE__CREATE, &ad);
1792         if (rc)
1793                 return rc;
1794
1795         return avc_has_perm(&selinux_state,
1796                             newsid, sbsec->sid,
1797                             SECCLASS_FILESYSTEM,
1798                             FILESYSTEM__ASSOCIATE, &ad);
1799 }
1800
1801 #define MAY_LINK        0
1802 #define MAY_UNLINK      1
1803 #define MAY_RMDIR       2
1804
1805 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1806 static int may_link(struct inode *dir,
1807                     struct dentry *dentry,
1808                     int kind)
1809
1810 {
1811         struct inode_security_struct *dsec, *isec;
1812         struct common_audit_data ad;
1813         u32 sid = current_sid();
1814         u32 av;
1815         int rc;
1816
1817         dsec = inode_security(dir);
1818         isec = backing_inode_security(dentry);
1819
1820         ad.type = LSM_AUDIT_DATA_DENTRY;
1821         ad.u.dentry = dentry;
1822
1823         av = DIR__SEARCH;
1824         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1825         rc = avc_has_perm(&selinux_state,
1826                           sid, dsec->sid, SECCLASS_DIR, av, &ad);
1827         if (rc)
1828                 return rc;
1829
1830         switch (kind) {
1831         case MAY_LINK:
1832                 av = FILE__LINK;
1833                 break;
1834         case MAY_UNLINK:
1835                 av = FILE__UNLINK;
1836                 break;
1837         case MAY_RMDIR:
1838                 av = DIR__RMDIR;
1839                 break;
1840         default:
1841                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
1842                         __func__, kind);
1843                 return 0;
1844         }
1845
1846         rc = avc_has_perm(&selinux_state,
1847                           sid, isec->sid, isec->sclass, av, &ad);
1848         return rc;
1849 }
1850
1851 static inline int may_rename(struct inode *old_dir,
1852                              struct dentry *old_dentry,
1853                              struct inode *new_dir,
1854                              struct dentry *new_dentry)
1855 {
1856         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1857         struct common_audit_data ad;
1858         u32 sid = current_sid();
1859         u32 av;
1860         int old_is_dir, new_is_dir;
1861         int rc;
1862
1863         old_dsec = inode_security(old_dir);
1864         old_isec = backing_inode_security(old_dentry);
1865         old_is_dir = d_is_dir(old_dentry);
1866         new_dsec = inode_security(new_dir);
1867
1868         ad.type = LSM_AUDIT_DATA_DENTRY;
1869
1870         ad.u.dentry = old_dentry;
1871         rc = avc_has_perm(&selinux_state,
1872                           sid, old_dsec->sid, SECCLASS_DIR,
1873                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1874         if (rc)
1875                 return rc;
1876         rc = avc_has_perm(&selinux_state,
1877                           sid, old_isec->sid,
1878                           old_isec->sclass, FILE__RENAME, &ad);
1879         if (rc)
1880                 return rc;
1881         if (old_is_dir && new_dir != old_dir) {
1882                 rc = avc_has_perm(&selinux_state,
1883                                   sid, old_isec->sid,
1884                                   old_isec->sclass, DIR__REPARENT, &ad);
1885                 if (rc)
1886                         return rc;
1887         }
1888
1889         ad.u.dentry = new_dentry;
1890         av = DIR__ADD_NAME | DIR__SEARCH;
1891         if (d_is_positive(new_dentry))
1892                 av |= DIR__REMOVE_NAME;
1893         rc = avc_has_perm(&selinux_state,
1894                           sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1895         if (rc)
1896                 return rc;
1897         if (d_is_positive(new_dentry)) {
1898                 new_isec = backing_inode_security(new_dentry);
1899                 new_is_dir = d_is_dir(new_dentry);
1900                 rc = avc_has_perm(&selinux_state,
1901                                   sid, new_isec->sid,
1902                                   new_isec->sclass,
1903                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1904                 if (rc)
1905                         return rc;
1906         }
1907
1908         return 0;
1909 }
1910
1911 /* Check whether a task can perform a filesystem operation. */
1912 static int superblock_has_perm(const struct cred *cred,
1913                                struct super_block *sb,
1914                                u32 perms,
1915                                struct common_audit_data *ad)
1916 {
1917         struct superblock_security_struct *sbsec;
1918         u32 sid = cred_sid(cred);
1919
1920         sbsec = selinux_superblock(sb);
1921         return avc_has_perm(&selinux_state,
1922                             sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1923 }
1924
1925 /* Convert a Linux mode and permission mask to an access vector. */
1926 static inline u32 file_mask_to_av(int mode, int mask)
1927 {
1928         u32 av = 0;
1929
1930         if (!S_ISDIR(mode)) {
1931                 if (mask & MAY_EXEC)
1932                         av |= FILE__EXECUTE;
1933                 if (mask & MAY_READ)
1934                         av |= FILE__READ;
1935
1936                 if (mask & MAY_APPEND)
1937                         av |= FILE__APPEND;
1938                 else if (mask & MAY_WRITE)
1939                         av |= FILE__WRITE;
1940
1941         } else {
1942                 if (mask & MAY_EXEC)
1943                         av |= DIR__SEARCH;
1944                 if (mask & MAY_WRITE)
1945                         av |= DIR__WRITE;
1946                 if (mask & MAY_READ)
1947                         av |= DIR__READ;
1948         }
1949
1950         return av;
1951 }
1952
1953 /* Convert a Linux file to an access vector. */
1954 static inline u32 file_to_av(struct file *file)
1955 {
1956         u32 av = 0;
1957
1958         if (file->f_mode & FMODE_READ)
1959                 av |= FILE__READ;
1960         if (file->f_mode & FMODE_WRITE) {
1961                 if (file->f_flags & O_APPEND)
1962                         av |= FILE__APPEND;
1963                 else
1964                         av |= FILE__WRITE;
1965         }
1966         if (!av) {
1967                 /*
1968                  * Special file opened with flags 3 for ioctl-only use.
1969                  */
1970                 av = FILE__IOCTL;
1971         }
1972
1973         return av;
1974 }
1975
1976 /*
1977  * Convert a file to an access vector and include the correct
1978  * open permission.
1979  */
1980 static inline u32 open_file_to_av(struct file *file)
1981 {
1982         u32 av = file_to_av(file);
1983         struct inode *inode = file_inode(file);
1984
1985         if (selinux_policycap_openperm() &&
1986             inode->i_sb->s_magic != SOCKFS_MAGIC)
1987                 av |= FILE__OPEN;
1988
1989         return av;
1990 }
1991
1992 /* Hook functions begin here. */
1993
1994 static int selinux_binder_set_context_mgr(const struct cred *mgr)
1995 {
1996         return avc_has_perm(&selinux_state,
1997                             current_sid(), cred_sid(mgr), SECCLASS_BINDER,
1998                             BINDER__SET_CONTEXT_MGR, NULL);
1999 }
2000
2001 static int selinux_binder_transaction(const struct cred *from,
2002                                       const struct cred *to)
2003 {
2004         u32 mysid = current_sid();
2005         u32 fromsid = cred_sid(from);
2006         u32 tosid = cred_sid(to);
2007         int rc;
2008
2009         if (mysid != fromsid) {
2010                 rc = avc_has_perm(&selinux_state,
2011                                   mysid, fromsid, SECCLASS_BINDER,
2012                                   BINDER__IMPERSONATE, NULL);
2013                 if (rc)
2014                         return rc;
2015         }
2016
2017         return avc_has_perm(&selinux_state, fromsid, tosid,
2018                             SECCLASS_BINDER, BINDER__CALL, NULL);
2019 }
2020
2021 static int selinux_binder_transfer_binder(const struct cred *from,
2022                                           const struct cred *to)
2023 {
2024         return avc_has_perm(&selinux_state,
2025                             cred_sid(from), cred_sid(to),
2026                             SECCLASS_BINDER, BINDER__TRANSFER,
2027                             NULL);
2028 }
2029
2030 static int selinux_binder_transfer_file(const struct cred *from,
2031                                         const struct cred *to,
2032                                         struct file *file)
2033 {
2034         u32 sid = cred_sid(to);
2035         struct file_security_struct *fsec = selinux_file(file);
2036         struct dentry *dentry = file->f_path.dentry;
2037         struct inode_security_struct *isec;
2038         struct common_audit_data ad;
2039         int rc;
2040
2041         ad.type = LSM_AUDIT_DATA_PATH;
2042         ad.u.path = file->f_path;
2043
2044         if (sid != fsec->sid) {
2045                 rc = avc_has_perm(&selinux_state,
2046                                   sid, fsec->sid,
2047                                   SECCLASS_FD,
2048                                   FD__USE,
2049                                   &ad);
2050                 if (rc)
2051                         return rc;
2052         }
2053
2054 #ifdef CONFIG_BPF_SYSCALL
2055         rc = bpf_fd_pass(file, sid);
2056         if (rc)
2057                 return rc;
2058 #endif
2059
2060         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2061                 return 0;
2062
2063         isec = backing_inode_security(dentry);
2064         return avc_has_perm(&selinux_state,
2065                             sid, isec->sid, isec->sclass, file_to_av(file),
2066                             &ad);
2067 }
2068
2069 static int selinux_ptrace_access_check(struct task_struct *child,
2070                                        unsigned int mode)
2071 {
2072         u32 sid = current_sid();
2073         u32 csid = task_sid_obj(child);
2074
2075         if (mode & PTRACE_MODE_READ)
2076                 return avc_has_perm(&selinux_state,
2077                                     sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2078
2079         return avc_has_perm(&selinux_state,
2080                             sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2081 }
2082
2083 static int selinux_ptrace_traceme(struct task_struct *parent)
2084 {
2085         return avc_has_perm(&selinux_state,
2086                             task_sid_obj(parent), task_sid_obj(current),
2087                             SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2088 }
2089
2090 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2091                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2092 {
2093         return avc_has_perm(&selinux_state,
2094                             current_sid(), task_sid_obj(target), SECCLASS_PROCESS,
2095                             PROCESS__GETCAP, NULL);
2096 }
2097
2098 static int selinux_capset(struct cred *new, const struct cred *old,
2099                           const kernel_cap_t *effective,
2100                           const kernel_cap_t *inheritable,
2101                           const kernel_cap_t *permitted)
2102 {
2103         return avc_has_perm(&selinux_state,
2104                             cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2105                             PROCESS__SETCAP, NULL);
2106 }
2107
2108 /*
2109  * (This comment used to live with the selinux_task_setuid hook,
2110  * which was removed).
2111  *
2112  * Since setuid only affects the current process, and since the SELinux
2113  * controls are not based on the Linux identity attributes, SELinux does not
2114  * need to control this operation.  However, SELinux does control the use of
2115  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2116  */
2117
2118 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2119                            int cap, unsigned int opts)
2120 {
2121         return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2122 }
2123
2124 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2125 {
2126         const struct cred *cred = current_cred();
2127         int rc = 0;
2128
2129         if (!sb)
2130                 return 0;
2131
2132         switch (cmds) {
2133         case Q_SYNC:
2134         case Q_QUOTAON:
2135         case Q_QUOTAOFF:
2136         case Q_SETINFO:
2137         case Q_SETQUOTA:
2138         case Q_XQUOTAOFF:
2139         case Q_XQUOTAON:
2140         case Q_XSETQLIM:
2141                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2142                 break;
2143         case Q_GETFMT:
2144         case Q_GETINFO:
2145         case Q_GETQUOTA:
2146         case Q_XGETQUOTA:
2147         case Q_XGETQSTAT:
2148         case Q_XGETQSTATV:
2149         case Q_XGETNEXTQUOTA:
2150                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2151                 break;
2152         default:
2153                 rc = 0;  /* let the kernel handle invalid cmds */
2154                 break;
2155         }
2156         return rc;
2157 }
2158
2159 static int selinux_quota_on(struct dentry *dentry)
2160 {
2161         const struct cred *cred = current_cred();
2162
2163         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2164 }
2165
2166 static int selinux_syslog(int type)
2167 {
2168         switch (type) {
2169         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2170         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2171                 return avc_has_perm(&selinux_state,
2172                                     current_sid(), SECINITSID_KERNEL,
2173                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2174         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2175         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2176         /* Set level of messages printed to console */
2177         case SYSLOG_ACTION_CONSOLE_LEVEL:
2178                 return avc_has_perm(&selinux_state,
2179                                     current_sid(), SECINITSID_KERNEL,
2180                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2181                                     NULL);
2182         }
2183         /* All other syslog types */
2184         return avc_has_perm(&selinux_state,
2185                             current_sid(), SECINITSID_KERNEL,
2186                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2187 }
2188
2189 /*
2190  * Check that a process has enough memory to allocate a new virtual
2191  * mapping. 0 means there is enough memory for the allocation to
2192  * succeed and -ENOMEM implies there is not.
2193  *
2194  * Do not audit the selinux permission check, as this is applied to all
2195  * processes that allocate mappings.
2196  */
2197 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2198 {
2199         int rc, cap_sys_admin = 0;
2200
2201         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2202                                  CAP_OPT_NOAUDIT, true);
2203         if (rc == 0)
2204                 cap_sys_admin = 1;
2205
2206         return cap_sys_admin;
2207 }
2208
2209 /* binprm security operations */
2210
2211 static u32 ptrace_parent_sid(void)
2212 {
2213         u32 sid = 0;
2214         struct task_struct *tracer;
2215
2216         rcu_read_lock();
2217         tracer = ptrace_parent(current);
2218         if (tracer)
2219                 sid = task_sid_obj(tracer);
2220         rcu_read_unlock();
2221
2222         return sid;
2223 }
2224
2225 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2226                             const struct task_security_struct *old_tsec,
2227                             const struct task_security_struct *new_tsec)
2228 {
2229         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2230         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2231         int rc;
2232         u32 av;
2233
2234         if (!nnp && !nosuid)
2235                 return 0; /* neither NNP nor nosuid */
2236
2237         if (new_tsec->sid == old_tsec->sid)
2238                 return 0; /* No change in credentials */
2239
2240         /*
2241          * If the policy enables the nnp_nosuid_transition policy capability,
2242          * then we permit transitions under NNP or nosuid if the
2243          * policy allows the corresponding permission between
2244          * the old and new contexts.
2245          */
2246         if (selinux_policycap_nnp_nosuid_transition()) {
2247                 av = 0;
2248                 if (nnp)
2249                         av |= PROCESS2__NNP_TRANSITION;
2250                 if (nosuid)
2251                         av |= PROCESS2__NOSUID_TRANSITION;
2252                 rc = avc_has_perm(&selinux_state,
2253                                   old_tsec->sid, new_tsec->sid,
2254                                   SECCLASS_PROCESS2, av, NULL);
2255                 if (!rc)
2256                         return 0;
2257         }
2258
2259         /*
2260          * We also permit NNP or nosuid transitions to bounded SIDs,
2261          * i.e. SIDs that are guaranteed to only be allowed a subset
2262          * of the permissions of the current SID.
2263          */
2264         rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2265                                          new_tsec->sid);
2266         if (!rc)
2267                 return 0;
2268
2269         /*
2270          * On failure, preserve the errno values for NNP vs nosuid.
2271          * NNP:  Operation not permitted for caller.
2272          * nosuid:  Permission denied to file.
2273          */
2274         if (nnp)
2275                 return -EPERM;
2276         return -EACCES;
2277 }
2278
2279 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2280 {
2281         const struct task_security_struct *old_tsec;
2282         struct task_security_struct *new_tsec;
2283         struct inode_security_struct *isec;
2284         struct common_audit_data ad;
2285         struct inode *inode = file_inode(bprm->file);
2286         int rc;
2287
2288         /* SELinux context only depends on initial program or script and not
2289          * the script interpreter */
2290
2291         old_tsec = selinux_cred(current_cred());
2292         new_tsec = selinux_cred(bprm->cred);
2293         isec = inode_security(inode);
2294
2295         /* Default to the current task SID. */
2296         new_tsec->sid = old_tsec->sid;
2297         new_tsec->osid = old_tsec->sid;
2298
2299         /* Reset fs, key, and sock SIDs on execve. */
2300         new_tsec->create_sid = 0;
2301         new_tsec->keycreate_sid = 0;
2302         new_tsec->sockcreate_sid = 0;
2303
2304         if (old_tsec->exec_sid) {
2305                 new_tsec->sid = old_tsec->exec_sid;
2306                 /* Reset exec SID on execve. */
2307                 new_tsec->exec_sid = 0;
2308
2309                 /* Fail on NNP or nosuid if not an allowed transition. */
2310                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2311                 if (rc)
2312                         return rc;
2313         } else {
2314                 /* Check for a default transition on this program. */
2315                 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2316                                              isec->sid, SECCLASS_PROCESS, NULL,
2317                                              &new_tsec->sid);
2318                 if (rc)
2319                         return rc;
2320
2321                 /*
2322                  * Fallback to old SID on NNP or nosuid if not an allowed
2323                  * transition.
2324                  */
2325                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2326                 if (rc)
2327                         new_tsec->sid = old_tsec->sid;
2328         }
2329
2330         ad.type = LSM_AUDIT_DATA_FILE;
2331         ad.u.file = bprm->file;
2332
2333         if (new_tsec->sid == old_tsec->sid) {
2334                 rc = avc_has_perm(&selinux_state,
2335                                   old_tsec->sid, isec->sid,
2336                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2337                 if (rc)
2338                         return rc;
2339         } else {
2340                 /* Check permissions for the transition. */
2341                 rc = avc_has_perm(&selinux_state,
2342                                   old_tsec->sid, new_tsec->sid,
2343                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2344                 if (rc)
2345                         return rc;
2346
2347                 rc = avc_has_perm(&selinux_state,
2348                                   new_tsec->sid, isec->sid,
2349                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2350                 if (rc)
2351                         return rc;
2352
2353                 /* Check for shared state */
2354                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2355                         rc = avc_has_perm(&selinux_state,
2356                                           old_tsec->sid, new_tsec->sid,
2357                                           SECCLASS_PROCESS, PROCESS__SHARE,
2358                                           NULL);
2359                         if (rc)
2360                                 return -EPERM;
2361                 }
2362
2363                 /* Make sure that anyone attempting to ptrace over a task that
2364                  * changes its SID has the appropriate permit */
2365                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2366                         u32 ptsid = ptrace_parent_sid();
2367                         if (ptsid != 0) {
2368                                 rc = avc_has_perm(&selinux_state,
2369                                                   ptsid, new_tsec->sid,
2370                                                   SECCLASS_PROCESS,
2371                                                   PROCESS__PTRACE, NULL);
2372                                 if (rc)
2373                                         return -EPERM;
2374                         }
2375                 }
2376
2377                 /* Clear any possibly unsafe personality bits on exec: */
2378                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2379
2380                 /* Enable secure mode for SIDs transitions unless
2381                    the noatsecure permission is granted between
2382                    the two SIDs, i.e. ahp returns 0. */
2383                 rc = avc_has_perm(&selinux_state,
2384                                   old_tsec->sid, new_tsec->sid,
2385                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2386                                   NULL);
2387                 bprm->secureexec |= !!rc;
2388         }
2389
2390         return 0;
2391 }
2392
2393 static int match_file(const void *p, struct file *file, unsigned fd)
2394 {
2395         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2396 }
2397
2398 /* Derived from fs/exec.c:flush_old_files. */
2399 static inline void flush_unauthorized_files(const struct cred *cred,
2400                                             struct files_struct *files)
2401 {
2402         struct file *file, *devnull = NULL;
2403         struct tty_struct *tty;
2404         int drop_tty = 0;
2405         unsigned n;
2406
2407         tty = get_current_tty();
2408         if (tty) {
2409                 spin_lock(&tty->files_lock);
2410                 if (!list_empty(&tty->tty_files)) {
2411                         struct tty_file_private *file_priv;
2412
2413                         /* Revalidate access to controlling tty.
2414                            Use file_path_has_perm on the tty path directly
2415                            rather than using file_has_perm, as this particular
2416                            open file may belong to another process and we are
2417                            only interested in the inode-based check here. */
2418                         file_priv = list_first_entry(&tty->tty_files,
2419                                                 struct tty_file_private, list);
2420                         file = file_priv->file;
2421                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2422                                 drop_tty = 1;
2423                 }
2424                 spin_unlock(&tty->files_lock);
2425                 tty_kref_put(tty);
2426         }
2427         /* Reset controlling tty. */
2428         if (drop_tty)
2429                 no_tty();
2430
2431         /* Revalidate access to inherited open files. */
2432         n = iterate_fd(files, 0, match_file, cred);
2433         if (!n) /* none found? */
2434                 return;
2435
2436         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2437         if (IS_ERR(devnull))
2438                 devnull = NULL;
2439         /* replace all the matching ones with this */
2440         do {
2441                 replace_fd(n - 1, devnull, 0);
2442         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2443         if (devnull)
2444                 fput(devnull);
2445 }
2446
2447 /*
2448  * Prepare a process for imminent new credential changes due to exec
2449  */
2450 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2451 {
2452         struct task_security_struct *new_tsec;
2453         struct rlimit *rlim, *initrlim;
2454         int rc, i;
2455
2456         new_tsec = selinux_cred(bprm->cred);
2457         if (new_tsec->sid == new_tsec->osid)
2458                 return;
2459
2460         /* Close files for which the new task SID is not authorized. */
2461         flush_unauthorized_files(bprm->cred, current->files);
2462
2463         /* Always clear parent death signal on SID transitions. */
2464         current->pdeath_signal = 0;
2465
2466         /* Check whether the new SID can inherit resource limits from the old
2467          * SID.  If not, reset all soft limits to the lower of the current
2468          * task's hard limit and the init task's soft limit.
2469          *
2470          * Note that the setting of hard limits (even to lower them) can be
2471          * controlled by the setrlimit check.  The inclusion of the init task's
2472          * soft limit into the computation is to avoid resetting soft limits
2473          * higher than the default soft limit for cases where the default is
2474          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2475          */
2476         rc = avc_has_perm(&selinux_state,
2477                           new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2478                           PROCESS__RLIMITINH, NULL);
2479         if (rc) {
2480                 /* protect against do_prlimit() */
2481                 task_lock(current);
2482                 for (i = 0; i < RLIM_NLIMITS; i++) {
2483                         rlim = current->signal->rlim + i;
2484                         initrlim = init_task.signal->rlim + i;
2485                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2486                 }
2487                 task_unlock(current);
2488                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2489                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2490         }
2491 }
2492
2493 /*
2494  * Clean up the process immediately after the installation of new credentials
2495  * due to exec
2496  */
2497 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2498 {
2499         const struct task_security_struct *tsec = selinux_cred(current_cred());
2500         u32 osid, sid;
2501         int rc;
2502
2503         osid = tsec->osid;
2504         sid = tsec->sid;
2505
2506         if (sid == osid)
2507                 return;
2508
2509         /* Check whether the new SID can inherit signal state from the old SID.
2510          * If not, clear itimers to avoid subsequent signal generation and
2511          * flush and unblock signals.
2512          *
2513          * This must occur _after_ the task SID has been updated so that any
2514          * kill done after the flush will be checked against the new SID.
2515          */
2516         rc = avc_has_perm(&selinux_state,
2517                           osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2518         if (rc) {
2519                 clear_itimer();
2520
2521                 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2522                 if (!fatal_signal_pending(current)) {
2523                         flush_sigqueue(&current->pending);
2524                         flush_sigqueue(&current->signal->shared_pending);
2525                         flush_signal_handlers(current, 1);
2526                         sigemptyset(&current->blocked);
2527                         recalc_sigpending();
2528                 }
2529                 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2530         }
2531
2532         /* Wake up the parent if it is waiting so that it can recheck
2533          * wait permission to the new task SID. */
2534         read_lock(&tasklist_lock);
2535         __wake_up_parent(current, unrcu_pointer(current->real_parent));
2536         read_unlock(&tasklist_lock);
2537 }
2538
2539 /* superblock security operations */
2540
2541 static int selinux_sb_alloc_security(struct super_block *sb)
2542 {
2543         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2544
2545         mutex_init(&sbsec->lock);
2546         INIT_LIST_HEAD(&sbsec->isec_head);
2547         spin_lock_init(&sbsec->isec_lock);
2548         sbsec->sid = SECINITSID_UNLABELED;
2549         sbsec->def_sid = SECINITSID_FILE;
2550         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2551
2552         return 0;
2553 }
2554
2555 static inline int opt_len(const char *s)
2556 {
2557         bool open_quote = false;
2558         int len;
2559         char c;
2560
2561         for (len = 0; (c = s[len]) != '\0'; len++) {
2562                 if (c == '"')
2563                         open_quote = !open_quote;
2564                 if (c == ',' && !open_quote)
2565                         break;
2566         }
2567         return len;
2568 }
2569
2570 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2571 {
2572         char *from = options;
2573         char *to = options;
2574         bool first = true;
2575         int rc;
2576
2577         while (1) {
2578                 int len = opt_len(from);
2579                 int token;
2580                 char *arg = NULL;
2581
2582                 token = match_opt_prefix(from, len, &arg);
2583
2584                 if (token != Opt_error) {
2585                         char *p, *q;
2586
2587                         /* strip quotes */
2588                         if (arg) {
2589                                 for (p = q = arg; p < from + len; p++) {
2590                                         char c = *p;
2591                                         if (c != '"')
2592                                                 *q++ = c;
2593                                 }
2594                                 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2595                                 if (!arg) {
2596                                         rc = -ENOMEM;
2597                                         goto free_opt;
2598                                 }
2599                         }
2600                         rc = selinux_add_opt(token, arg, mnt_opts);
2601                         kfree(arg);
2602                         arg = NULL;
2603                         if (unlikely(rc)) {
2604                                 goto free_opt;
2605                         }
2606                 } else {
2607                         if (!first) {   // copy with preceding comma
2608                                 from--;
2609                                 len++;
2610                         }
2611                         if (to != from)
2612                                 memmove(to, from, len);
2613                         to += len;
2614                         first = false;
2615                 }
2616                 if (!from[len])
2617                         break;
2618                 from += len + 1;
2619         }
2620         *to = '\0';
2621         return 0;
2622
2623 free_opt:
2624         if (*mnt_opts) {
2625                 selinux_free_mnt_opts(*mnt_opts);
2626                 *mnt_opts = NULL;
2627         }
2628         return rc;
2629 }
2630
2631 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2632 {
2633         struct selinux_mnt_opts *opts = mnt_opts;
2634         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2635
2636         /*
2637          * Superblock not initialized (i.e. no options) - reject if any
2638          * options specified, otherwise accept.
2639          */
2640         if (!(sbsec->flags & SE_SBINITIALIZED))
2641                 return opts ? 1 : 0;
2642
2643         /*
2644          * Superblock initialized and no options specified - reject if
2645          * superblock has any options set, otherwise accept.
2646          */
2647         if (!opts)
2648                 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2649
2650         if (opts->fscontext_sid) {
2651                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2652                                opts->fscontext_sid))
2653                         return 1;
2654         }
2655         if (opts->context_sid) {
2656                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2657                                opts->context_sid))
2658                         return 1;
2659         }
2660         if (opts->rootcontext_sid) {
2661                 struct inode_security_struct *root_isec;
2662
2663                 root_isec = backing_inode_security(sb->s_root);
2664                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2665                                opts->rootcontext_sid))
2666                         return 1;
2667         }
2668         if (opts->defcontext_sid) {
2669                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2670                                opts->defcontext_sid))
2671                         return 1;
2672         }
2673         return 0;
2674 }
2675
2676 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2677 {
2678         struct selinux_mnt_opts *opts = mnt_opts;
2679         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2680
2681         if (!(sbsec->flags & SE_SBINITIALIZED))
2682                 return 0;
2683
2684         if (!opts)
2685                 return 0;
2686
2687         if (opts->fscontext_sid) {
2688                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2689                                opts->fscontext_sid))
2690                         goto out_bad_option;
2691         }
2692         if (opts->context_sid) {
2693                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2694                                opts->context_sid))
2695                         goto out_bad_option;
2696         }
2697         if (opts->rootcontext_sid) {
2698                 struct inode_security_struct *root_isec;
2699                 root_isec = backing_inode_security(sb->s_root);
2700                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2701                                opts->rootcontext_sid))
2702                         goto out_bad_option;
2703         }
2704         if (opts->defcontext_sid) {
2705                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2706                                opts->defcontext_sid))
2707                         goto out_bad_option;
2708         }
2709         return 0;
2710
2711 out_bad_option:
2712         pr_warn("SELinux: unable to change security options "
2713                "during remount (dev %s, type=%s)\n", sb->s_id,
2714                sb->s_type->name);
2715         return -EINVAL;
2716 }
2717
2718 static int selinux_sb_kern_mount(struct super_block *sb)
2719 {
2720         const struct cred *cred = current_cred();
2721         struct common_audit_data ad;
2722
2723         ad.type = LSM_AUDIT_DATA_DENTRY;
2724         ad.u.dentry = sb->s_root;
2725         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2726 }
2727
2728 static int selinux_sb_statfs(struct dentry *dentry)
2729 {
2730         const struct cred *cred = current_cred();
2731         struct common_audit_data ad;
2732
2733         ad.type = LSM_AUDIT_DATA_DENTRY;
2734         ad.u.dentry = dentry->d_sb->s_root;
2735         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2736 }
2737
2738 static int selinux_mount(const char *dev_name,
2739                          const struct path *path,
2740                          const char *type,
2741                          unsigned long flags,
2742                          void *data)
2743 {
2744         const struct cred *cred = current_cred();
2745
2746         if (flags & MS_REMOUNT)
2747                 return superblock_has_perm(cred, path->dentry->d_sb,
2748                                            FILESYSTEM__REMOUNT, NULL);
2749         else
2750                 return path_has_perm(cred, path, FILE__MOUNTON);
2751 }
2752
2753 static int selinux_move_mount(const struct path *from_path,
2754                               const struct path *to_path)
2755 {
2756         const struct cred *cred = current_cred();
2757
2758         return path_has_perm(cred, to_path, FILE__MOUNTON);
2759 }
2760
2761 static int selinux_umount(struct vfsmount *mnt, int flags)
2762 {
2763         const struct cred *cred = current_cred();
2764
2765         return superblock_has_perm(cred, mnt->mnt_sb,
2766                                    FILESYSTEM__UNMOUNT, NULL);
2767 }
2768
2769 static int selinux_fs_context_dup(struct fs_context *fc,
2770                                   struct fs_context *src_fc)
2771 {
2772         const struct selinux_mnt_opts *src = src_fc->security;
2773
2774         if (!src)
2775                 return 0;
2776
2777         fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2778         return fc->security ? 0 : -ENOMEM;
2779 }
2780
2781 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2782         fsparam_string(CONTEXT_STR,     Opt_context),
2783         fsparam_string(DEFCONTEXT_STR,  Opt_defcontext),
2784         fsparam_string(FSCONTEXT_STR,   Opt_fscontext),
2785         fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2786         fsparam_flag  (SECLABEL_STR,    Opt_seclabel),
2787         {}
2788 };
2789
2790 static int selinux_fs_context_parse_param(struct fs_context *fc,
2791                                           struct fs_parameter *param)
2792 {
2793         struct fs_parse_result result;
2794         int opt;
2795
2796         opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2797         if (opt < 0)
2798                 return opt;
2799
2800         return selinux_add_opt(opt, param->string, &fc->security);
2801 }
2802
2803 /* inode security operations */
2804
2805 static int selinux_inode_alloc_security(struct inode *inode)
2806 {
2807         struct inode_security_struct *isec = selinux_inode(inode);
2808         u32 sid = current_sid();
2809
2810         spin_lock_init(&isec->lock);
2811         INIT_LIST_HEAD(&isec->list);
2812         isec->inode = inode;
2813         isec->sid = SECINITSID_UNLABELED;
2814         isec->sclass = SECCLASS_FILE;
2815         isec->task_sid = sid;
2816         isec->initialized = LABEL_INVALID;
2817
2818         return 0;
2819 }
2820
2821 static void selinux_inode_free_security(struct inode *inode)
2822 {
2823         inode_free_security(inode);
2824 }
2825
2826 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2827                                         const struct qstr *name,
2828                                         const char **xattr_name, void **ctx,
2829                                         u32 *ctxlen)
2830 {
2831         u32 newsid;
2832         int rc;
2833
2834         rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2835                                            d_inode(dentry->d_parent), name,
2836                                            inode_mode_to_security_class(mode),
2837                                            &newsid);
2838         if (rc)
2839                 return rc;
2840
2841         if (xattr_name)
2842                 *xattr_name = XATTR_NAME_SELINUX;
2843
2844         return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2845                                        ctxlen);
2846 }
2847
2848 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2849                                           struct qstr *name,
2850                                           const struct cred *old,
2851                                           struct cred *new)
2852 {
2853         u32 newsid;
2854         int rc;
2855         struct task_security_struct *tsec;
2856
2857         rc = selinux_determine_inode_label(selinux_cred(old),
2858                                            d_inode(dentry->d_parent), name,
2859                                            inode_mode_to_security_class(mode),
2860                                            &newsid);
2861         if (rc)
2862                 return rc;
2863
2864         tsec = selinux_cred(new);
2865         tsec->create_sid = newsid;
2866         return 0;
2867 }
2868
2869 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2870                                        const struct qstr *qstr,
2871                                        const char **name,
2872                                        void **value, size_t *len)
2873 {
2874         const struct task_security_struct *tsec = selinux_cred(current_cred());
2875         struct superblock_security_struct *sbsec;
2876         u32 newsid, clen;
2877         int rc;
2878         char *context;
2879
2880         sbsec = selinux_superblock(dir->i_sb);
2881
2882         newsid = tsec->create_sid;
2883
2884         rc = selinux_determine_inode_label(tsec, dir, qstr,
2885                 inode_mode_to_security_class(inode->i_mode),
2886                 &newsid);
2887         if (rc)
2888                 return rc;
2889
2890         /* Possibly defer initialization to selinux_complete_init. */
2891         if (sbsec->flags & SE_SBINITIALIZED) {
2892                 struct inode_security_struct *isec = selinux_inode(inode);
2893                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2894                 isec->sid = newsid;
2895                 isec->initialized = LABEL_INITIALIZED;
2896         }
2897
2898         if (!selinux_initialized(&selinux_state) ||
2899             !(sbsec->flags & SBLABEL_MNT))
2900                 return -EOPNOTSUPP;
2901
2902         if (name)
2903                 *name = XATTR_SELINUX_SUFFIX;
2904
2905         if (value && len) {
2906                 rc = security_sid_to_context_force(&selinux_state, newsid,
2907                                                    &context, &clen);
2908                 if (rc)
2909                         return rc;
2910                 *value = context;
2911                 *len = clen;
2912         }
2913
2914         return 0;
2915 }
2916
2917 static int selinux_inode_init_security_anon(struct inode *inode,
2918                                             const struct qstr *name,
2919                                             const struct inode *context_inode)
2920 {
2921         const struct task_security_struct *tsec = selinux_cred(current_cred());
2922         struct common_audit_data ad;
2923         struct inode_security_struct *isec;
2924         int rc;
2925
2926         if (unlikely(!selinux_initialized(&selinux_state)))
2927                 return 0;
2928
2929         isec = selinux_inode(inode);
2930
2931         /*
2932          * We only get here once per ephemeral inode.  The inode has
2933          * been initialized via inode_alloc_security but is otherwise
2934          * untouched.
2935          */
2936
2937         if (context_inode) {
2938                 struct inode_security_struct *context_isec =
2939                         selinux_inode(context_inode);
2940                 if (context_isec->initialized != LABEL_INITIALIZED) {
2941                         pr_err("SELinux:  context_inode is not initialized");
2942                         return -EACCES;
2943                 }
2944
2945                 isec->sclass = context_isec->sclass;
2946                 isec->sid = context_isec->sid;
2947         } else {
2948                 isec->sclass = SECCLASS_ANON_INODE;
2949                 rc = security_transition_sid(
2950                         &selinux_state, tsec->sid, tsec->sid,
2951                         isec->sclass, name, &isec->sid);
2952                 if (rc)
2953                         return rc;
2954         }
2955
2956         isec->initialized = LABEL_INITIALIZED;
2957         /*
2958          * Now that we've initialized security, check whether we're
2959          * allowed to actually create this type of anonymous inode.
2960          */
2961
2962         ad.type = LSM_AUDIT_DATA_ANONINODE;
2963         ad.u.anonclass = name ? (const char *)name->name : "?";
2964
2965         return avc_has_perm(&selinux_state,
2966                             tsec->sid,
2967                             isec->sid,
2968                             isec->sclass,
2969                             FILE__CREATE,
2970                             &ad);
2971 }
2972
2973 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2974 {
2975         return may_create(dir, dentry, SECCLASS_FILE);
2976 }
2977
2978 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2979 {
2980         return may_link(dir, old_dentry, MAY_LINK);
2981 }
2982
2983 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2984 {
2985         return may_link(dir, dentry, MAY_UNLINK);
2986 }
2987
2988 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2989 {
2990         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2991 }
2992
2993 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2994 {
2995         return may_create(dir, dentry, SECCLASS_DIR);
2996 }
2997
2998 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2999 {
3000         return may_link(dir, dentry, MAY_RMDIR);
3001 }
3002
3003 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3004 {
3005         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3006 }
3007
3008 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3009                                 struct inode *new_inode, struct dentry *new_dentry)
3010 {
3011         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3012 }
3013
3014 static int selinux_inode_readlink(struct dentry *dentry)
3015 {
3016         const struct cred *cred = current_cred();
3017
3018         return dentry_has_perm(cred, dentry, FILE__READ);
3019 }
3020
3021 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3022                                      bool rcu)
3023 {
3024         const struct cred *cred = current_cred();
3025         struct common_audit_data ad;
3026         struct inode_security_struct *isec;
3027         u32 sid;
3028
3029         validate_creds(cred);
3030
3031         ad.type = LSM_AUDIT_DATA_DENTRY;
3032         ad.u.dentry = dentry;
3033         sid = cred_sid(cred);
3034         isec = inode_security_rcu(inode, rcu);
3035         if (IS_ERR(isec))
3036                 return PTR_ERR(isec);
3037
3038         return avc_has_perm(&selinux_state,
3039                                   sid, isec->sid, isec->sclass, FILE__READ, &ad);
3040 }
3041
3042 static noinline int audit_inode_permission(struct inode *inode,
3043                                            u32 perms, u32 audited, u32 denied,
3044                                            int result)
3045 {
3046         struct common_audit_data ad;
3047         struct inode_security_struct *isec = selinux_inode(inode);
3048
3049         ad.type = LSM_AUDIT_DATA_INODE;
3050         ad.u.inode = inode;
3051
3052         return slow_avc_audit(&selinux_state,
3053                             current_sid(), isec->sid, isec->sclass, perms,
3054                             audited, denied, result, &ad);
3055 }
3056
3057 static int selinux_inode_permission(struct inode *inode, int mask)
3058 {
3059         const struct cred *cred = current_cred();
3060         u32 perms;
3061         bool from_access;
3062         bool no_block = mask & MAY_NOT_BLOCK;
3063         struct inode_security_struct *isec;
3064         u32 sid;
3065         struct av_decision avd;
3066         int rc, rc2;
3067         u32 audited, denied;
3068
3069         from_access = mask & MAY_ACCESS;
3070         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3071
3072         /* No permission to check.  Existence test. */
3073         if (!mask)
3074                 return 0;
3075
3076         validate_creds(cred);
3077
3078         if (unlikely(IS_PRIVATE(inode)))
3079                 return 0;
3080
3081         perms = file_mask_to_av(inode->i_mode, mask);
3082
3083         sid = cred_sid(cred);
3084         isec = inode_security_rcu(inode, no_block);
3085         if (IS_ERR(isec))
3086                 return PTR_ERR(isec);
3087
3088         rc = avc_has_perm_noaudit(&selinux_state,
3089                                   sid, isec->sid, isec->sclass, perms, 0,
3090                                   &avd);
3091         audited = avc_audit_required(perms, &avd, rc,
3092                                      from_access ? FILE__AUDIT_ACCESS : 0,
3093                                      &denied);
3094         if (likely(!audited))
3095                 return rc;
3096
3097         rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3098         if (rc2)
3099                 return rc2;
3100         return rc;
3101 }
3102
3103 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3104 {
3105         const struct cred *cred = current_cred();
3106         struct inode *inode = d_backing_inode(dentry);
3107         unsigned int ia_valid = iattr->ia_valid;
3108         __u32 av = FILE__WRITE;
3109
3110         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3111         if (ia_valid & ATTR_FORCE) {
3112                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3113                               ATTR_FORCE);
3114                 if (!ia_valid)
3115                         return 0;
3116         }
3117
3118         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3119                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3120                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3121
3122         if (selinux_policycap_openperm() &&
3123             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3124             (ia_valid & ATTR_SIZE) &&
3125             !(ia_valid & ATTR_FILE))
3126                 av |= FILE__OPEN;
3127
3128         return dentry_has_perm(cred, dentry, av);
3129 }
3130
3131 static int selinux_inode_getattr(const struct path *path)
3132 {
3133         return path_has_perm(current_cred(), path, FILE__GETATTR);
3134 }
3135
3136 static bool has_cap_mac_admin(bool audit)
3137 {
3138         const struct cred *cred = current_cred();
3139         unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3140
3141         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3142                 return false;
3143         if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3144                 return false;
3145         return true;
3146 }
3147
3148 static int selinux_inode_setxattr(struct user_namespace *mnt_userns,
3149                                   struct dentry *dentry, const char *name,
3150                                   const void *value, size_t size, int flags)
3151 {
3152         struct inode *inode = d_backing_inode(dentry);
3153         struct inode_security_struct *isec;
3154         struct superblock_security_struct *sbsec;
3155         struct common_audit_data ad;
3156         u32 newsid, sid = current_sid();
3157         int rc = 0;
3158
3159         if (strcmp(name, XATTR_NAME_SELINUX)) {
3160                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3161                 if (rc)
3162                         return rc;
3163
3164                 /* Not an attribute we recognize, so just check the
3165                    ordinary setattr permission. */
3166                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3167         }
3168
3169         if (!selinux_initialized(&selinux_state))
3170                 return (inode_owner_or_capable(mnt_userns, inode) ? 0 : -EPERM);
3171
3172         sbsec = selinux_superblock(inode->i_sb);
3173         if (!(sbsec->flags & SBLABEL_MNT))
3174                 return -EOPNOTSUPP;
3175
3176         if (!inode_owner_or_capable(mnt_userns, inode))
3177                 return -EPERM;
3178
3179         ad.type = LSM_AUDIT_DATA_DENTRY;
3180         ad.u.dentry = dentry;
3181
3182         isec = backing_inode_security(dentry);
3183         rc = avc_has_perm(&selinux_state,
3184                           sid, isec->sid, isec->sclass,
3185                           FILE__RELABELFROM, &ad);
3186         if (rc)
3187                 return rc;
3188
3189         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3190                                      GFP_KERNEL);
3191         if (rc == -EINVAL) {
3192                 if (!has_cap_mac_admin(true)) {
3193                         struct audit_buffer *ab;
3194                         size_t audit_size;
3195
3196                         /* We strip a nul only if it is at the end, otherwise the
3197                          * context contains a nul and we should audit that */
3198                         if (value) {
3199                                 const char *str = value;
3200
3201                                 if (str[size - 1] == '\0')
3202                                         audit_size = size - 1;
3203                                 else
3204                                         audit_size = size;
3205                         } else {
3206                                 audit_size = 0;
3207                         }
3208                         ab = audit_log_start(audit_context(),
3209                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3210                         if (!ab)
3211                                 return rc;
3212                         audit_log_format(ab, "op=setxattr invalid_context=");
3213                         audit_log_n_untrustedstring(ab, value, audit_size);
3214                         audit_log_end(ab);
3215
3216                         return rc;
3217                 }
3218                 rc = security_context_to_sid_force(&selinux_state, value,
3219                                                    size, &newsid);
3220         }
3221         if (rc)
3222                 return rc;
3223
3224         rc = avc_has_perm(&selinux_state,
3225                           sid, newsid, isec->sclass,
3226                           FILE__RELABELTO, &ad);
3227         if (rc)
3228                 return rc;
3229
3230         rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3231                                           sid, isec->sclass);
3232         if (rc)
3233                 return rc;
3234
3235         return avc_has_perm(&selinux_state,
3236                             newsid,
3237                             sbsec->sid,
3238                             SECCLASS_FILESYSTEM,
3239                             FILESYSTEM__ASSOCIATE,
3240                             &ad);
3241 }
3242
3243 static int selinux_inode_set_acl(struct user_namespace *mnt_userns,
3244                                  struct dentry *dentry, const char *acl_name,
3245                                  struct posix_acl *kacl)
3246 {
3247         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3248 }
3249
3250 static int selinux_inode_get_acl(struct user_namespace *mnt_userns,
3251                                  struct dentry *dentry, const char *acl_name)
3252 {
3253         return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3254 }
3255
3256 static int selinux_inode_remove_acl(struct user_namespace *mnt_userns,
3257                                     struct dentry *dentry, const char *acl_name)
3258 {
3259         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3260 }
3261
3262 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3263                                         const void *value, size_t size,
3264                                         int flags)
3265 {
3266         struct inode *inode = d_backing_inode(dentry);
3267         struct inode_security_struct *isec;
3268         u32 newsid;
3269         int rc;
3270
3271         if (strcmp(name, XATTR_NAME_SELINUX)) {
3272                 /* Not an attribute we recognize, so nothing to do. */
3273                 return;
3274         }
3275
3276         if (!selinux_initialized(&selinux_state)) {
3277                 /* If we haven't even been initialized, then we can't validate
3278                  * against a policy, so leave the label as invalid. It may
3279                  * resolve to a valid label on the next revalidation try if
3280                  * we've since initialized.
3281                  */
3282                 return;
3283         }
3284
3285         rc = security_context_to_sid_force(&selinux_state, value, size,
3286                                            &newsid);
3287         if (rc) {
3288                 pr_err("SELinux:  unable to map context to SID"
3289                        "for (%s, %lu), rc=%d\n",
3290                        inode->i_sb->s_id, inode->i_ino, -rc);
3291                 return;
3292         }
3293
3294         isec = backing_inode_security(dentry);
3295         spin_lock(&isec->lock);
3296         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3297         isec->sid = newsid;
3298         isec->initialized = LABEL_INITIALIZED;
3299         spin_unlock(&isec->lock);
3300 }
3301
3302 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3303 {
3304         const struct cred *cred = current_cred();
3305
3306         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3307 }
3308
3309 static int selinux_inode_listxattr(struct dentry *dentry)
3310 {
3311         const struct cred *cred = current_cred();
3312
3313         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3314 }
3315
3316 static int selinux_inode_removexattr(struct user_namespace *mnt_userns,
3317                                      struct dentry *dentry, const char *name)
3318 {
3319         if (strcmp(name, XATTR_NAME_SELINUX)) {
3320                 int rc = cap_inode_removexattr(mnt_userns, dentry, name);
3321                 if (rc)
3322                         return rc;
3323
3324                 /* Not an attribute we recognize, so just check the
3325                    ordinary setattr permission. */
3326                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3327         }
3328
3329         if (!selinux_initialized(&selinux_state))
3330                 return 0;
3331
3332         /* No one is allowed to remove a SELinux security label.
3333            You can change the label, but all data must be labeled. */
3334         return -EACCES;
3335 }
3336
3337 static int selinux_path_notify(const struct path *path, u64 mask,
3338                                                 unsigned int obj_type)
3339 {
3340         int ret;
3341         u32 perm;
3342
3343         struct common_audit_data ad;
3344
3345         ad.type = LSM_AUDIT_DATA_PATH;
3346         ad.u.path = *path;
3347
3348         /*
3349          * Set permission needed based on the type of mark being set.
3350          * Performs an additional check for sb watches.
3351          */
3352         switch (obj_type) {
3353         case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3354                 perm = FILE__WATCH_MOUNT;
3355                 break;
3356         case FSNOTIFY_OBJ_TYPE_SB:
3357                 perm = FILE__WATCH_SB;
3358                 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3359                                                 FILESYSTEM__WATCH, &ad);
3360                 if (ret)
3361                         return ret;
3362                 break;
3363         case FSNOTIFY_OBJ_TYPE_INODE:
3364                 perm = FILE__WATCH;
3365                 break;
3366         default:
3367                 return -EINVAL;
3368         }
3369
3370         /* blocking watches require the file:watch_with_perm permission */
3371         if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3372                 perm |= FILE__WATCH_WITH_PERM;
3373
3374         /* watches on read-like events need the file:watch_reads permission */
3375         if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3376                 perm |= FILE__WATCH_READS;
3377
3378         return path_has_perm(current_cred(), path, perm);
3379 }
3380
3381 /*
3382  * Copy the inode security context value to the user.
3383  *
3384  * Permission check is handled by selinux_inode_getxattr hook.
3385  */
3386 static int selinux_inode_getsecurity(struct user_namespace *mnt_userns,
3387                                      struct inode *inode, const char *name,
3388                                      void **buffer, bool alloc)
3389 {
3390         u32 size;
3391         int error;
3392         char *context = NULL;
3393         struct inode_security_struct *isec;
3394
3395         /*
3396          * If we're not initialized yet, then we can't validate contexts, so
3397          * just let vfs_getxattr fall back to using the on-disk xattr.
3398          */
3399         if (!selinux_initialized(&selinux_state) ||
3400             strcmp(name, XATTR_SELINUX_SUFFIX))
3401                 return -EOPNOTSUPP;
3402
3403         /*
3404          * If the caller has CAP_MAC_ADMIN, then get the raw context
3405          * value even if it is not defined by current policy; otherwise,
3406          * use the in-core value under current policy.
3407          * Use the non-auditing forms of the permission checks since
3408          * getxattr may be called by unprivileged processes commonly
3409          * and lack of permission just means that we fall back to the
3410          * in-core context value, not a denial.
3411          */
3412         isec = inode_security(inode);
3413         if (has_cap_mac_admin(false))
3414                 error = security_sid_to_context_force(&selinux_state,
3415                                                       isec->sid, &context,
3416                                                       &size);
3417         else
3418                 error = security_sid_to_context(&selinux_state, isec->sid,
3419                                                 &context, &size);
3420         if (error)
3421                 return error;
3422         error = size;
3423         if (alloc) {
3424                 *buffer = context;
3425                 goto out_nofree;
3426         }
3427         kfree(context);
3428 out_nofree:
3429         return error;
3430 }
3431
3432 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3433                                      const void *value, size_t size, int flags)
3434 {
3435         struct inode_security_struct *isec = inode_security_novalidate(inode);
3436         struct superblock_security_struct *sbsec;
3437         u32 newsid;
3438         int rc;
3439
3440         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3441                 return -EOPNOTSUPP;
3442
3443         sbsec = selinux_superblock(inode->i_sb);
3444         if (!(sbsec->flags & SBLABEL_MNT))
3445                 return -EOPNOTSUPP;
3446
3447         if (!value || !size)
3448                 return -EACCES;
3449
3450         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3451                                      GFP_KERNEL);
3452         if (rc)
3453                 return rc;
3454
3455         spin_lock(&isec->lock);
3456         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3457         isec->sid = newsid;
3458         isec->initialized = LABEL_INITIALIZED;
3459         spin_unlock(&isec->lock);
3460         return 0;
3461 }
3462
3463 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3464 {
3465         const int len = sizeof(XATTR_NAME_SELINUX);
3466
3467         if (!selinux_initialized(&selinux_state))
3468                 return 0;
3469
3470         if (buffer && len <= buffer_size)
3471                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3472         return len;
3473 }
3474
3475 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3476 {
3477         struct inode_security_struct *isec = inode_security_novalidate(inode);
3478         *secid = isec->sid;
3479 }
3480
3481 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3482 {
3483         u32 sid;
3484         struct task_security_struct *tsec;
3485         struct cred *new_creds = *new;
3486
3487         if (new_creds == NULL) {
3488                 new_creds = prepare_creds();
3489                 if (!new_creds)
3490                         return -ENOMEM;
3491         }
3492
3493         tsec = selinux_cred(new_creds);
3494         /* Get label from overlay inode and set it in create_sid */
3495         selinux_inode_getsecid(d_inode(src), &sid);
3496         tsec->create_sid = sid;
3497         *new = new_creds;
3498         return 0;
3499 }
3500
3501 static int selinux_inode_copy_up_xattr(const char *name)
3502 {
3503         /* The copy_up hook above sets the initial context on an inode, but we
3504          * don't then want to overwrite it by blindly copying all the lower
3505          * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3506          */
3507         if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3508                 return 1; /* Discard */
3509         /*
3510          * Any other attribute apart from SELINUX is not claimed, supported
3511          * by selinux.
3512          */
3513         return -EOPNOTSUPP;
3514 }
3515
3516 /* kernfs node operations */
3517
3518 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3519                                         struct kernfs_node *kn)
3520 {
3521         const struct task_security_struct *tsec = selinux_cred(current_cred());
3522         u32 parent_sid, newsid, clen;
3523         int rc;
3524         char *context;
3525
3526         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3527         if (rc == -ENODATA)
3528                 return 0;
3529         else if (rc < 0)
3530                 return rc;
3531
3532         clen = (u32)rc;
3533         context = kmalloc(clen, GFP_KERNEL);
3534         if (!context)
3535                 return -ENOMEM;
3536
3537         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3538         if (rc < 0) {
3539                 kfree(context);
3540                 return rc;
3541         }
3542
3543         rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3544                                      GFP_KERNEL);
3545         kfree(context);
3546         if (rc)
3547                 return rc;
3548
3549         if (tsec->create_sid) {
3550                 newsid = tsec->create_sid;
3551         } else {
3552                 u16 secclass = inode_mode_to_security_class(kn->mode);
3553                 struct qstr q;
3554
3555                 q.name = kn->name;
3556                 q.hash_len = hashlen_string(kn_dir, kn->name);
3557
3558                 rc = security_transition_sid(&selinux_state, tsec->sid,
3559                                              parent_sid, secclass, &q,
3560                                              &newsid);
3561                 if (rc)
3562                         return rc;
3563         }
3564
3565         rc = security_sid_to_context_force(&selinux_state, newsid,
3566                                            &context, &clen);
3567         if (rc)
3568                 return rc;
3569
3570         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3571                               XATTR_CREATE);
3572         kfree(context);
3573         return rc;
3574 }
3575
3576
3577 /* file security operations */
3578
3579 static int selinux_revalidate_file_permission(struct file *file, int mask)
3580 {
3581         const struct cred *cred = current_cred();
3582         struct inode *inode = file_inode(file);
3583
3584         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3585         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3586                 mask |= MAY_APPEND;
3587
3588         return file_has_perm(cred, file,
3589                              file_mask_to_av(inode->i_mode, mask));
3590 }
3591
3592 static int selinux_file_permission(struct file *file, int mask)
3593 {
3594         struct inode *inode = file_inode(file);
3595         struct file_security_struct *fsec = selinux_file(file);
3596         struct inode_security_struct *isec;
3597         u32 sid = current_sid();
3598
3599         if (!mask)
3600                 /* No permission to check.  Existence test. */
3601                 return 0;
3602
3603         isec = inode_security(inode);
3604         if (sid == fsec->sid && fsec->isid == isec->sid &&
3605             fsec->pseqno == avc_policy_seqno(&selinux_state))
3606                 /* No change since file_open check. */
3607                 return 0;
3608
3609         return selinux_revalidate_file_permission(file, mask);
3610 }
3611
3612 static int selinux_file_alloc_security(struct file *file)
3613 {
3614         struct file_security_struct *fsec = selinux_file(file);
3615         u32 sid = current_sid();
3616
3617         fsec->sid = sid;
3618         fsec->fown_sid = sid;
3619
3620         return 0;
3621 }
3622
3623 /*
3624  * Check whether a task has the ioctl permission and cmd
3625  * operation to an inode.
3626  */
3627 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3628                 u32 requested, u16 cmd)
3629 {
3630         struct common_audit_data ad;
3631         struct file_security_struct *fsec = selinux_file(file);
3632         struct inode *inode = file_inode(file);
3633         struct inode_security_struct *isec;
3634         struct lsm_ioctlop_audit ioctl;
3635         u32 ssid = cred_sid(cred);
3636         int rc;
3637         u8 driver = cmd >> 8;
3638         u8 xperm = cmd & 0xff;
3639
3640         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3641         ad.u.op = &ioctl;
3642         ad.u.op->cmd = cmd;
3643         ad.u.op->path = file->f_path;
3644
3645         if (ssid != fsec->sid) {
3646                 rc = avc_has_perm(&selinux_state,
3647                                   ssid, fsec->sid,
3648                                 SECCLASS_FD,
3649                                 FD__USE,
3650                                 &ad);
3651                 if (rc)
3652                         goto out;
3653         }
3654
3655         if (unlikely(IS_PRIVATE(inode)))
3656                 return 0;
3657
3658         isec = inode_security(inode);
3659         rc = avc_has_extended_perms(&selinux_state,
3660                                     ssid, isec->sid, isec->sclass,
3661                                     requested, driver, xperm, &ad);
3662 out:
3663         return rc;
3664 }
3665
3666 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3667                               unsigned long arg)
3668 {
3669         const struct cred *cred = current_cred();
3670         int error = 0;
3671
3672         switch (cmd) {
3673         case FIONREAD:
3674         case FIBMAP:
3675         case FIGETBSZ:
3676         case FS_IOC_GETFLAGS:
3677         case FS_IOC_GETVERSION:
3678                 error = file_has_perm(cred, file, FILE__GETATTR);
3679                 break;
3680
3681         case FS_IOC_SETFLAGS:
3682         case FS_IOC_SETVERSION:
3683                 error = file_has_perm(cred, file, FILE__SETATTR);
3684                 break;
3685
3686         /* sys_ioctl() checks */
3687         case FIONBIO:
3688         case FIOASYNC:
3689                 error = file_has_perm(cred, file, 0);
3690                 break;
3691
3692         case KDSKBENT:
3693         case KDSKBSENT:
3694                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3695                                             CAP_OPT_NONE, true);
3696                 break;
3697
3698         case FIOCLEX:
3699         case FIONCLEX:
3700                 if (!selinux_policycap_ioctl_skip_cloexec())
3701                         error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3702                 break;
3703
3704         /* default case assumes that the command will go
3705          * to the file's ioctl() function.
3706          */
3707         default:
3708                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3709         }
3710         return error;
3711 }
3712
3713 static int default_noexec __ro_after_init;
3714
3715 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3716 {
3717         const struct cred *cred = current_cred();
3718         u32 sid = cred_sid(cred);
3719         int rc = 0;
3720
3721         if (default_noexec &&
3722             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3723                                    (!shared && (prot & PROT_WRITE)))) {
3724                 /*
3725                  * We are making executable an anonymous mapping or a
3726                  * private file mapping that will also be writable.
3727                  * This has an additional check.
3728                  */
3729                 rc = avc_has_perm(&selinux_state,
3730                                   sid, sid, SECCLASS_PROCESS,
3731                                   PROCESS__EXECMEM, NULL);
3732                 if (rc)
3733                         goto error;
3734         }
3735
3736         if (file) {
3737                 /* read access is always possible with a mapping */
3738                 u32 av = FILE__READ;
3739
3740                 /* write access only matters if the mapping is shared */
3741                 if (shared && (prot & PROT_WRITE))
3742                         av |= FILE__WRITE;
3743
3744                 if (prot & PROT_EXEC)
3745                         av |= FILE__EXECUTE;
3746
3747                 return file_has_perm(cred, file, av);
3748         }
3749
3750 error:
3751         return rc;
3752 }
3753
3754 static int selinux_mmap_addr(unsigned long addr)
3755 {
3756         int rc = 0;
3757
3758         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3759                 u32 sid = current_sid();
3760                 rc = avc_has_perm(&selinux_state,
3761                                   sid, sid, SECCLASS_MEMPROTECT,
3762                                   MEMPROTECT__MMAP_ZERO, NULL);
3763         }
3764
3765         return rc;
3766 }
3767
3768 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3769                              unsigned long prot, unsigned long flags)
3770 {
3771         struct common_audit_data ad;
3772         int rc;
3773
3774         if (file) {
3775                 ad.type = LSM_AUDIT_DATA_FILE;
3776                 ad.u.file = file;
3777                 rc = inode_has_perm(current_cred(), file_inode(file),
3778                                     FILE__MAP, &ad);
3779                 if (rc)
3780                         return rc;
3781         }
3782
3783         if (checkreqprot_get(&selinux_state))
3784                 prot = reqprot;
3785
3786         return file_map_prot_check(file, prot,
3787                                    (flags & MAP_TYPE) == MAP_SHARED);
3788 }
3789
3790 static int selinux_file_mprotect(struct vm_area_struct *vma,
3791                                  unsigned long reqprot,
3792                                  unsigned long prot)
3793 {
3794         const struct cred *cred = current_cred();
3795         u32 sid = cred_sid(cred);
3796
3797         if (checkreqprot_get(&selinux_state))
3798                 prot = reqprot;
3799
3800         if (default_noexec &&
3801             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3802                 int rc = 0;
3803                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3804                     vma->vm_end <= vma->vm_mm->brk) {
3805                         rc = avc_has_perm(&selinux_state,
3806                                           sid, sid, SECCLASS_PROCESS,
3807                                           PROCESS__EXECHEAP, NULL);
3808                 } else if (!vma->vm_file &&
3809                            ((vma->vm_start <= vma->vm_mm->start_stack &&
3810                              vma->vm_end >= vma->vm_mm->start_stack) ||
3811                             vma_is_stack_for_current(vma))) {
3812                         rc = avc_has_perm(&selinux_state,
3813                                           sid, sid, SECCLASS_PROCESS,
3814                                           PROCESS__EXECSTACK, NULL);
3815                 } else if (vma->vm_file && vma->anon_vma) {
3816                         /*
3817                          * We are making executable a file mapping that has
3818                          * had some COW done. Since pages might have been
3819                          * written, check ability to execute the possibly
3820                          * modified content.  This typically should only
3821                          * occur for text relocations.
3822                          */
3823                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3824                 }
3825                 if (rc)
3826                         return rc;
3827         }
3828
3829         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3830 }
3831
3832 static int selinux_file_lock(struct file *file, unsigned int cmd)
3833 {
3834         const struct cred *cred = current_cred();
3835
3836         return file_has_perm(cred, file, FILE__LOCK);
3837 }
3838
3839 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3840                               unsigned long arg)
3841 {
3842         const struct cred *cred = current_cred();
3843         int err = 0;
3844
3845         switch (cmd) {
3846         case F_SETFL:
3847                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3848                         err = file_has_perm(cred, file, FILE__WRITE);
3849                         break;
3850                 }
3851                 fallthrough;
3852         case F_SETOWN:
3853         case F_SETSIG:
3854         case F_GETFL:
3855         case F_GETOWN:
3856         case F_GETSIG:
3857         case F_GETOWNER_UIDS:
3858                 /* Just check FD__USE permission */
3859                 err = file_has_perm(cred, file, 0);
3860                 break;
3861         case F_GETLK:
3862         case F_SETLK:
3863         case F_SETLKW:
3864         case F_OFD_GETLK:
3865         case F_OFD_SETLK:
3866         case F_OFD_SETLKW:
3867 #if BITS_PER_LONG == 32
3868         case F_GETLK64:
3869         case F_SETLK64:
3870         case F_SETLKW64:
3871 #endif
3872                 err = file_has_perm(cred, file, FILE__LOCK);
3873                 break;
3874         }
3875
3876         return err;
3877 }
3878
3879 static void selinux_file_set_fowner(struct file *file)
3880 {
3881         struct file_security_struct *fsec;
3882
3883         fsec = selinux_file(file);
3884         fsec->fown_sid = current_sid();
3885 }
3886
3887 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3888                                        struct fown_struct *fown, int signum)
3889 {
3890         struct file *file;
3891         u32 sid = task_sid_obj(tsk);
3892         u32 perm;
3893         struct file_security_struct *fsec;
3894
3895         /* struct fown_struct is never outside the context of a struct file */
3896         file = container_of(fown, struct file, f_owner);
3897
3898         fsec = selinux_file(file);
3899
3900         if (!signum)
3901                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3902         else
3903                 perm = signal_to_av(signum);
3904
3905         return avc_has_perm(&selinux_state,
3906                             fsec->fown_sid, sid,
3907                             SECCLASS_PROCESS, perm, NULL);
3908 }
3909
3910 static int selinux_file_receive(struct file *file)
3911 {
3912         const struct cred *cred = current_cred();
3913
3914         return file_has_perm(cred, file, file_to_av(file));
3915 }
3916
3917 static int selinux_file_open(struct file *file)
3918 {
3919         struct file_security_struct *fsec;
3920         struct inode_security_struct *isec;
3921
3922         fsec = selinux_file(file);
3923         isec = inode_security(file_inode(file));
3924         /*
3925          * Save inode label and policy sequence number
3926          * at open-time so that selinux_file_permission
3927          * can determine whether revalidation is necessary.
3928          * Task label is already saved in the file security
3929          * struct as its SID.
3930          */
3931         fsec->isid = isec->sid;
3932         fsec->pseqno = avc_policy_seqno(&selinux_state);
3933         /*
3934          * Since the inode label or policy seqno may have changed
3935          * between the selinux_inode_permission check and the saving
3936          * of state above, recheck that access is still permitted.
3937          * Otherwise, access might never be revalidated against the
3938          * new inode label or new policy.
3939          * This check is not redundant - do not remove.
3940          */
3941         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3942 }
3943
3944 /* task security operations */
3945
3946 static int selinux_task_alloc(struct task_struct *task,
3947                               unsigned long clone_flags)
3948 {
3949         u32 sid = current_sid();
3950
3951         return avc_has_perm(&selinux_state,
3952                             sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3953 }
3954
3955 /*
3956  * prepare a new set of credentials for modification
3957  */
3958 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3959                                 gfp_t gfp)
3960 {
3961         const struct task_security_struct *old_tsec = selinux_cred(old);
3962         struct task_security_struct *tsec = selinux_cred(new);
3963
3964         *tsec = *old_tsec;
3965         return 0;
3966 }
3967
3968 /*
3969  * transfer the SELinux data to a blank set of creds
3970  */
3971 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3972 {
3973         const struct task_security_struct *old_tsec = selinux_cred(old);
3974         struct task_security_struct *tsec = selinux_cred(new);
3975
3976         *tsec = *old_tsec;
3977 }
3978
3979 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3980 {
3981         *secid = cred_sid(c);
3982 }
3983
3984 /*
3985  * set the security data for a kernel service
3986  * - all the creation contexts are set to unlabelled
3987  */
3988 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3989 {
3990         struct task_security_struct *tsec = selinux_cred(new);
3991         u32 sid = current_sid();
3992         int ret;
3993
3994         ret = avc_has_perm(&selinux_state,
3995                            sid, secid,
3996                            SECCLASS_KERNEL_SERVICE,
3997                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3998                            NULL);
3999         if (ret == 0) {
4000                 tsec->sid = secid;
4001                 tsec->create_sid = 0;
4002                 tsec->keycreate_sid = 0;
4003                 tsec->sockcreate_sid = 0;
4004         }
4005         return ret;
4006 }
4007
4008 /*
4009  * set the file creation context in a security record to the same as the
4010  * objective context of the specified inode
4011  */
4012 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4013 {
4014         struct inode_security_struct *isec = inode_security(inode);
4015         struct task_security_struct *tsec = selinux_cred(new);
4016         u32 sid = current_sid();
4017         int ret;
4018
4019         ret = avc_has_perm(&selinux_state,
4020                            sid, isec->sid,
4021                            SECCLASS_KERNEL_SERVICE,
4022                            KERNEL_SERVICE__CREATE_FILES_AS,
4023                            NULL);
4024
4025         if (ret == 0)
4026                 tsec->create_sid = isec->sid;
4027         return ret;
4028 }
4029
4030 static int selinux_kernel_module_request(char *kmod_name)
4031 {
4032         struct common_audit_data ad;
4033
4034         ad.type = LSM_AUDIT_DATA_KMOD;
4035         ad.u.kmod_name = kmod_name;
4036
4037         return avc_has_perm(&selinux_state,
4038                             current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4039                             SYSTEM__MODULE_REQUEST, &ad);
4040 }
4041
4042 static int selinux_kernel_module_from_file(struct file *file)
4043 {
4044         struct common_audit_data ad;
4045         struct inode_security_struct *isec;
4046         struct file_security_struct *fsec;
4047         u32 sid = current_sid();
4048         int rc;
4049
4050         /* init_module */
4051         if (file == NULL)
4052                 return avc_has_perm(&selinux_state,
4053                                     sid, sid, SECCLASS_SYSTEM,
4054                                         SYSTEM__MODULE_LOAD, NULL);
4055
4056         /* finit_module */
4057
4058         ad.type = LSM_AUDIT_DATA_FILE;
4059         ad.u.file = file;
4060
4061         fsec = selinux_file(file);
4062         if (sid != fsec->sid) {
4063                 rc = avc_has_perm(&selinux_state,
4064                                   sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4065                 if (rc)
4066                         return rc;
4067         }
4068
4069         isec = inode_security(file_inode(file));
4070         return avc_has_perm(&selinux_state,
4071                             sid, isec->sid, SECCLASS_SYSTEM,
4072                                 SYSTEM__MODULE_LOAD, &ad);
4073 }
4074
4075 static int selinux_kernel_read_file(struct file *file,
4076                                     enum kernel_read_file_id id,
4077                                     bool contents)
4078 {
4079         int rc = 0;
4080
4081         switch (id) {
4082         case READING_MODULE:
4083                 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4084                 break;
4085         default:
4086                 break;
4087         }
4088
4089         return rc;
4090 }
4091
4092 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4093 {
4094         int rc = 0;
4095
4096         switch (id) {
4097         case LOADING_MODULE:
4098                 rc = selinux_kernel_module_from_file(NULL);
4099                 break;
4100         default:
4101                 break;
4102         }
4103
4104         return rc;
4105 }
4106
4107 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4108 {
4109         return avc_has_perm(&selinux_state,
4110                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4111                             PROCESS__SETPGID, NULL);
4112 }
4113
4114 static int selinux_task_getpgid(struct task_struct *p)
4115 {
4116         return avc_has_perm(&selinux_state,
4117                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4118                             PROCESS__GETPGID, NULL);
4119 }
4120
4121 static int selinux_task_getsid(struct task_struct *p)
4122 {
4123         return avc_has_perm(&selinux_state,
4124                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4125                             PROCESS__GETSESSION, NULL);
4126 }
4127
4128 static void selinux_current_getsecid_subj(u32 *secid)
4129 {
4130         *secid = current_sid();
4131 }
4132
4133 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4134 {
4135         *secid = task_sid_obj(p);
4136 }
4137
4138 static int selinux_task_setnice(struct task_struct *p, int nice)
4139 {
4140         return avc_has_perm(&selinux_state,
4141                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4142                             PROCESS__SETSCHED, NULL);
4143 }
4144
4145 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4146 {
4147         return avc_has_perm(&selinux_state,
4148                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4149                             PROCESS__SETSCHED, NULL);
4150 }
4151
4152 static int selinux_task_getioprio(struct task_struct *p)
4153 {
4154         return avc_has_perm(&selinux_state,
4155                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4156                             PROCESS__GETSCHED, NULL);
4157 }
4158
4159 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4160                                 unsigned int flags)
4161 {
4162         u32 av = 0;
4163
4164         if (!flags)
4165                 return 0;
4166         if (flags & LSM_PRLIMIT_WRITE)
4167                 av |= PROCESS__SETRLIMIT;
4168         if (flags & LSM_PRLIMIT_READ)
4169                 av |= PROCESS__GETRLIMIT;
4170         return avc_has_perm(&selinux_state,
4171                             cred_sid(cred), cred_sid(tcred),
4172                             SECCLASS_PROCESS, av, NULL);
4173 }
4174
4175 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4176                 struct rlimit *new_rlim)
4177 {
4178         struct rlimit *old_rlim = p->signal->rlim + resource;
4179
4180         /* Control the ability to change the hard limit (whether
4181            lowering or raising it), so that the hard limit can
4182            later be used as a safe reset point for the soft limit
4183            upon context transitions.  See selinux_bprm_committing_creds. */
4184         if (old_rlim->rlim_max != new_rlim->rlim_max)
4185                 return avc_has_perm(&selinux_state,
4186                                     current_sid(), task_sid_obj(p),
4187                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4188
4189         return 0;
4190 }
4191
4192 static int selinux_task_setscheduler(struct task_struct *p)
4193 {
4194         return avc_has_perm(&selinux_state,
4195                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4196                             PROCESS__SETSCHED, NULL);
4197 }
4198
4199 static int selinux_task_getscheduler(struct task_struct *p)
4200 {
4201         return avc_has_perm(&selinux_state,
4202                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4203                             PROCESS__GETSCHED, NULL);
4204 }
4205
4206 static int selinux_task_movememory(struct task_struct *p)
4207 {
4208         return avc_has_perm(&selinux_state,
4209                             current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4210                             PROCESS__SETSCHED, NULL);
4211 }
4212
4213 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4214                                 int sig, const struct cred *cred)
4215 {
4216         u32 secid;
4217         u32 perm;
4218
4219         if (!sig)
4220                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4221         else
4222                 perm = signal_to_av(sig);
4223         if (!cred)
4224                 secid = current_sid();
4225         else
4226                 secid = cred_sid(cred);
4227         return avc_has_perm(&selinux_state,
4228                             secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4229 }
4230
4231 static void selinux_task_to_inode(struct task_struct *p,
4232                                   struct inode *inode)
4233 {
4234         struct inode_security_struct *isec = selinux_inode(inode);
4235         u32 sid = task_sid_obj(p);
4236
4237         spin_lock(&isec->lock);
4238         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4239         isec->sid = sid;
4240         isec->initialized = LABEL_INITIALIZED;
4241         spin_unlock(&isec->lock);
4242 }
4243
4244 static int selinux_userns_create(const struct cred *cred)
4245 {
4246         u32 sid = current_sid();
4247
4248         return avc_has_perm(&selinux_state, sid, sid, SECCLASS_USER_NAMESPACE,
4249                                                 USER_NAMESPACE__CREATE, NULL);
4250 }
4251
4252 /* Returns error only if unable to parse addresses */
4253 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4254                         struct common_audit_data *ad, u8 *proto)
4255 {
4256         int offset, ihlen, ret = -EINVAL;
4257         struct iphdr _iph, *ih;
4258
4259         offset = skb_network_offset(skb);
4260         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4261         if (ih == NULL)
4262                 goto out;
4263
4264         ihlen = ih->ihl * 4;
4265         if (ihlen < sizeof(_iph))
4266                 goto out;
4267
4268         ad->u.net->v4info.saddr = ih->saddr;
4269         ad->u.net->v4info.daddr = ih->daddr;
4270         ret = 0;
4271
4272         if (proto)
4273                 *proto = ih->protocol;
4274
4275         switch (ih->protocol) {
4276         case IPPROTO_TCP: {
4277                 struct tcphdr _tcph, *th;
4278
4279                 if (ntohs(ih->frag_off) & IP_OFFSET)
4280                         break;
4281
4282                 offset += ihlen;
4283                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4284                 if (th == NULL)
4285                         break;
4286
4287                 ad->u.net->sport = th->source;
4288                 ad->u.net->dport = th->dest;
4289                 break;
4290         }
4291
4292         case IPPROTO_UDP: {
4293                 struct udphdr _udph, *uh;
4294
4295                 if (ntohs(ih->frag_off) & IP_OFFSET)
4296                         break;
4297
4298                 offset += ihlen;
4299                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4300                 if (uh == NULL)
4301                         break;
4302
4303                 ad->u.net->sport = uh->source;
4304                 ad->u.net->dport = uh->dest;
4305                 break;
4306         }
4307
4308         case IPPROTO_DCCP: {
4309                 struct dccp_hdr _dccph, *dh;
4310
4311                 if (ntohs(ih->frag_off) & IP_OFFSET)
4312                         break;
4313
4314                 offset += ihlen;
4315                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4316                 if (dh == NULL)
4317                         break;
4318
4319                 ad->u.net->sport = dh->dccph_sport;
4320                 ad->u.net->dport = dh->dccph_dport;
4321                 break;
4322         }
4323
4324 #if IS_ENABLED(CONFIG_IP_SCTP)
4325         case IPPROTO_SCTP: {
4326                 struct sctphdr _sctph, *sh;
4327
4328                 if (ntohs(ih->frag_off) & IP_OFFSET)
4329                         break;
4330
4331                 offset += ihlen;
4332                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4333                 if (sh == NULL)
4334                         break;
4335
4336                 ad->u.net->sport = sh->source;
4337                 ad->u.net->dport = sh->dest;
4338                 break;
4339         }
4340 #endif
4341         default:
4342                 break;
4343         }
4344 out:
4345         return ret;
4346 }
4347
4348 #if IS_ENABLED(CONFIG_IPV6)
4349
4350 /* Returns error only if unable to parse addresses */
4351 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4352                         struct common_audit_data *ad, u8 *proto)
4353 {
4354         u8 nexthdr;
4355         int ret = -EINVAL, offset;
4356         struct ipv6hdr _ipv6h, *ip6;
4357         __be16 frag_off;
4358
4359         offset = skb_network_offset(skb);
4360         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4361         if (ip6 == NULL)
4362                 goto out;
4363
4364         ad->u.net->v6info.saddr = ip6->saddr;
4365         ad->u.net->v6info.daddr = ip6->daddr;
4366         ret = 0;
4367
4368         nexthdr = ip6->nexthdr;
4369         offset += sizeof(_ipv6h);
4370         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4371         if (offset < 0)
4372                 goto out;
4373
4374         if (proto)
4375                 *proto = nexthdr;
4376
4377         switch (nexthdr) {
4378         case IPPROTO_TCP: {
4379                 struct tcphdr _tcph, *th;
4380
4381                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4382                 if (th == NULL)
4383                         break;
4384
4385                 ad->u.net->sport = th->source;
4386                 ad->u.net->dport = th->dest;
4387                 break;
4388         }
4389
4390         case IPPROTO_UDP: {
4391                 struct udphdr _udph, *uh;
4392
4393                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4394                 if (uh == NULL)
4395                         break;
4396
4397                 ad->u.net->sport = uh->source;
4398                 ad->u.net->dport = uh->dest;
4399                 break;
4400         }
4401
4402         case IPPROTO_DCCP: {
4403                 struct dccp_hdr _dccph, *dh;
4404
4405                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4406                 if (dh == NULL)
4407                         break;
4408
4409                 ad->u.net->sport = dh->dccph_sport;
4410                 ad->u.net->dport = dh->dccph_dport;
4411                 break;
4412         }
4413
4414 #if IS_ENABLED(CONFIG_IP_SCTP)
4415         case IPPROTO_SCTP: {
4416                 struct sctphdr _sctph, *sh;
4417
4418                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4419                 if (sh == NULL)
4420                         break;
4421
4422                 ad->u.net->sport = sh->source;
4423                 ad->u.net->dport = sh->dest;
4424                 break;
4425         }
4426 #endif
4427         /* includes fragments */
4428         default:
4429                 break;
4430         }
4431 out:
4432         return ret;
4433 }
4434
4435 #endif /* IPV6 */
4436
4437 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4438                              char **_addrp, int src, u8 *proto)
4439 {
4440         char *addrp;
4441         int ret;
4442
4443         switch (ad->u.net->family) {
4444         case PF_INET:
4445                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4446                 if (ret)
4447                         goto parse_error;
4448                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4449                                        &ad->u.net->v4info.daddr);
4450                 goto okay;
4451
4452 #if IS_ENABLED(CONFIG_IPV6)
4453         case PF_INET6:
4454                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4455                 if (ret)
4456                         goto parse_error;
4457                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4458                                        &ad->u.net->v6info.daddr);
4459                 goto okay;
4460 #endif  /* IPV6 */
4461         default:
4462                 addrp = NULL;
4463                 goto okay;
4464         }
4465
4466 parse_error:
4467         pr_warn(
4468                "SELinux: failure in selinux_parse_skb(),"
4469                " unable to parse packet\n");
4470         return ret;
4471
4472 okay:
4473         if (_addrp)
4474                 *_addrp = addrp;
4475         return 0;
4476 }
4477
4478 /**
4479  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4480  * @skb: the packet
4481  * @family: protocol family
4482  * @sid: the packet's peer label SID
4483  *
4484  * Description:
4485  * Check the various different forms of network peer labeling and determine
4486  * the peer label/SID for the packet; most of the magic actually occurs in
4487  * the security server function security_net_peersid_cmp().  The function
4488  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4489  * or -EACCES if @sid is invalid due to inconsistencies with the different
4490  * peer labels.
4491  *
4492  */
4493 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4494 {
4495         int err;
4496         u32 xfrm_sid;
4497         u32 nlbl_sid;
4498         u32 nlbl_type;
4499
4500         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4501         if (unlikely(err))
4502                 return -EACCES;
4503         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4504         if (unlikely(err))
4505                 return -EACCES;
4506
4507         err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4508                                            nlbl_type, xfrm_sid, sid);
4509         if (unlikely(err)) {
4510                 pr_warn(
4511                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4512                        " unable to determine packet's peer label\n");
4513                 return -EACCES;
4514         }
4515
4516         return 0;
4517 }
4518
4519 /**
4520  * selinux_conn_sid - Determine the child socket label for a connection
4521  * @sk_sid: the parent socket's SID
4522  * @skb_sid: the packet's SID
4523  * @conn_sid: the resulting connection SID
4524  *
4525  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4526  * combined with the MLS information from @skb_sid in order to create
4527  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4528  * of @sk_sid.  Returns zero on success, negative values on failure.
4529  *
4530  */
4531 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4532 {
4533         int err = 0;
4534
4535         if (skb_sid != SECSID_NULL)
4536                 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4537                                             conn_sid);
4538         else
4539                 *conn_sid = sk_sid;
4540
4541         return err;
4542 }
4543
4544 /* socket security operations */
4545
4546 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4547                                  u16 secclass, u32 *socksid)
4548 {
4549         if (tsec->sockcreate_sid > SECSID_NULL) {
4550                 *socksid = tsec->sockcreate_sid;
4551                 return 0;
4552         }
4553
4554         return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4555                                        secclass, NULL, socksid);
4556 }
4557
4558 static int sock_has_perm(struct sock *sk, u32 perms)
4559 {
4560         struct sk_security_struct *sksec = sk->sk_security;
4561         struct common_audit_data ad;
4562         struct lsm_network_audit net = {0,};
4563
4564         if (sksec->sid == SECINITSID_KERNEL)
4565                 return 0;
4566
4567         ad.type = LSM_AUDIT_DATA_NET;
4568         ad.u.net = &net;
4569         ad.u.net->sk = sk;
4570
4571         return avc_has_perm(&selinux_state,
4572                             current_sid(), sksec->sid, sksec->sclass, perms,
4573                             &ad);
4574 }
4575
4576 static int selinux_socket_create(int family, int type,
4577                                  int protocol, int kern)
4578 {
4579         const struct task_security_struct *tsec = selinux_cred(current_cred());
4580         u32 newsid;
4581         u16 secclass;
4582         int rc;
4583
4584         if (kern)
4585                 return 0;
4586
4587         secclass = socket_type_to_security_class(family, type, protocol);
4588         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4589         if (rc)
4590                 return rc;
4591
4592         return avc_has_perm(&selinux_state,
4593                             tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4594 }
4595
4596 static int selinux_socket_post_create(struct socket *sock, int family,
4597                                       int type, int protocol, int kern)
4598 {
4599         const struct task_security_struct *tsec = selinux_cred(current_cred());
4600         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4601         struct sk_security_struct *sksec;
4602         u16 sclass = socket_type_to_security_class(family, type, protocol);
4603         u32 sid = SECINITSID_KERNEL;
4604         int err = 0;
4605
4606         if (!kern) {
4607                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4608                 if (err)
4609                         return err;
4610         }
4611
4612         isec->sclass = sclass;
4613         isec->sid = sid;
4614         isec->initialized = LABEL_INITIALIZED;
4615
4616         if (sock->sk) {
4617                 sksec = sock->sk->sk_security;
4618                 sksec->sclass = sclass;
4619                 sksec->sid = sid;
4620                 /* Allows detection of the first association on this socket */
4621                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4622                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4623
4624                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4625         }
4626
4627         return err;
4628 }
4629
4630 static int selinux_socket_socketpair(struct socket *socka,
4631                                      struct socket *sockb)
4632 {
4633         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4634         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4635
4636         sksec_a->peer_sid = sksec_b->sid;
4637         sksec_b->peer_sid = sksec_a->sid;
4638
4639         return 0;
4640 }
4641
4642 /* Range of port numbers used to automatically bind.
4643    Need to determine whether we should perform a name_bind
4644    permission check between the socket and the port number. */
4645
4646 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4647 {
4648         struct sock *sk = sock->sk;
4649         struct sk_security_struct *sksec = sk->sk_security;
4650         u16 family;
4651         int err;
4652
4653         err = sock_has_perm(sk, SOCKET__BIND);
4654         if (err)
4655                 goto out;
4656
4657         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4658         family = sk->sk_family;
4659         if (family == PF_INET || family == PF_INET6) {
4660                 char *addrp;
4661                 struct common_audit_data ad;
4662                 struct lsm_network_audit net = {0,};
4663                 struct sockaddr_in *addr4 = NULL;
4664                 struct sockaddr_in6 *addr6 = NULL;
4665                 u16 family_sa;
4666                 unsigned short snum;
4667                 u32 sid, node_perm;
4668
4669                 /*
4670                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4671                  * that validates multiple binding addresses. Because of this
4672                  * need to check address->sa_family as it is possible to have
4673                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4674                  */
4675                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4676                         return -EINVAL;
4677                 family_sa = address->sa_family;
4678                 switch (family_sa) {
4679                 case AF_UNSPEC:
4680                 case AF_INET:
4681                         if (addrlen < sizeof(struct sockaddr_in))
4682                                 return -EINVAL;
4683                         addr4 = (struct sockaddr_in *)address;
4684                         if (family_sa == AF_UNSPEC) {
4685                                 /* see __inet_bind(), we only want to allow
4686                                  * AF_UNSPEC if the address is INADDR_ANY
4687                                  */
4688                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4689                                         goto err_af;
4690                                 family_sa = AF_INET;
4691                         }
4692                         snum = ntohs(addr4->sin_port);
4693                         addrp = (char *)&addr4->sin_addr.s_addr;
4694                         break;
4695                 case AF_INET6:
4696                         if (addrlen < SIN6_LEN_RFC2133)
4697                                 return -EINVAL;
4698                         addr6 = (struct sockaddr_in6 *)address;
4699                         snum = ntohs(addr6->sin6_port);
4700                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4701                         break;
4702                 default:
4703                         goto err_af;
4704                 }
4705
4706                 ad.type = LSM_AUDIT_DATA_NET;
4707                 ad.u.net = &net;
4708                 ad.u.net->sport = htons(snum);
4709                 ad.u.net->family = family_sa;
4710
4711                 if (snum) {
4712                         int low, high;
4713
4714                         inet_get_local_port_range(sock_net(sk), &low, &high);
4715
4716                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4717                             snum < low || snum > high) {
4718                                 err = sel_netport_sid(sk->sk_protocol,
4719                                                       snum, &sid);
4720                                 if (err)
4721                                         goto out;
4722                                 err = avc_has_perm(&selinux_state,
4723                                                    sksec->sid, sid,
4724                                                    sksec->sclass,
4725                                                    SOCKET__NAME_BIND, &ad);
4726                                 if (err)
4727                                         goto out;
4728                         }
4729                 }
4730
4731                 switch (sksec->sclass) {
4732                 case SECCLASS_TCP_SOCKET:
4733                         node_perm = TCP_SOCKET__NODE_BIND;
4734                         break;
4735
4736                 case SECCLASS_UDP_SOCKET:
4737                         node_perm = UDP_SOCKET__NODE_BIND;
4738                         break;
4739
4740                 case SECCLASS_DCCP_SOCKET:
4741                         node_perm = DCCP_SOCKET__NODE_BIND;
4742                         break;
4743
4744                 case SECCLASS_SCTP_SOCKET:
4745                         node_perm = SCTP_SOCKET__NODE_BIND;
4746                         break;
4747
4748                 default:
4749                         node_perm = RAWIP_SOCKET__NODE_BIND;
4750                         break;
4751                 }
4752
4753                 err = sel_netnode_sid(addrp, family_sa, &sid);
4754                 if (err)
4755                         goto out;
4756
4757                 if (family_sa == AF_INET)
4758                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4759                 else
4760                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4761
4762                 err = avc_has_perm(&selinux_state,
4763                                    sksec->sid, sid,
4764                                    sksec->sclass, node_perm, &ad);
4765                 if (err)
4766                         goto out;
4767         }
4768 out:
4769         return err;
4770 err_af:
4771         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4772         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4773                 return -EINVAL;
4774         return -EAFNOSUPPORT;
4775 }
4776
4777 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4778  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4779  */
4780 static int selinux_socket_connect_helper(struct socket *sock,
4781                                          struct sockaddr *address, int addrlen)
4782 {
4783         struct sock *sk = sock->sk;
4784         struct sk_security_struct *sksec = sk->sk_security;
4785         int err;
4786
4787         err = sock_has_perm(sk, SOCKET__CONNECT);
4788         if (err)
4789                 return err;
4790         if (addrlen < offsetofend(struct sockaddr, sa_family))
4791                 return -EINVAL;
4792
4793         /* connect(AF_UNSPEC) has special handling, as it is a documented
4794          * way to disconnect the socket
4795          */
4796         if (address->sa_family == AF_UNSPEC)
4797                 return 0;
4798
4799         /*
4800          * If a TCP, DCCP or SCTP socket, check name_connect permission
4801          * for the port.
4802          */
4803         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4804             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4805             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4806                 struct common_audit_data ad;
4807                 struct lsm_network_audit net = {0,};
4808                 struct sockaddr_in *addr4 = NULL;
4809                 struct sockaddr_in6 *addr6 = NULL;
4810                 unsigned short snum;
4811                 u32 sid, perm;
4812
4813                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4814                  * that validates multiple connect addresses. Because of this
4815                  * need to check address->sa_family as it is possible to have
4816                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4817                  */
4818                 switch (address->sa_family) {
4819                 case AF_INET:
4820                         addr4 = (struct sockaddr_in *)address;
4821                         if (addrlen < sizeof(struct sockaddr_in))
4822                                 return -EINVAL;
4823                         snum = ntohs(addr4->sin_port);
4824                         break;
4825                 case AF_INET6:
4826                         addr6 = (struct sockaddr_in6 *)address;
4827                         if (addrlen < SIN6_LEN_RFC2133)
4828                                 return -EINVAL;
4829                         snum = ntohs(addr6->sin6_port);
4830                         break;
4831                 default:
4832                         /* Note that SCTP services expect -EINVAL, whereas
4833                          * others expect -EAFNOSUPPORT.
4834                          */
4835                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4836                                 return -EINVAL;
4837                         else
4838                                 return -EAFNOSUPPORT;
4839                 }
4840
4841                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4842                 if (err)
4843                         return err;
4844
4845                 switch (sksec->sclass) {
4846                 case SECCLASS_TCP_SOCKET:
4847                         perm = TCP_SOCKET__NAME_CONNECT;
4848                         break;
4849                 case SECCLASS_DCCP_SOCKET:
4850                         perm = DCCP_SOCKET__NAME_CONNECT;
4851                         break;
4852                 case SECCLASS_SCTP_SOCKET:
4853                         perm = SCTP_SOCKET__NAME_CONNECT;
4854                         break;
4855                 }
4856
4857                 ad.type = LSM_AUDIT_DATA_NET;
4858                 ad.u.net = &net;
4859                 ad.u.net->dport = htons(snum);
4860                 ad.u.net->family = address->sa_family;
4861                 err = avc_has_perm(&selinux_state,
4862                                    sksec->sid, sid, sksec->sclass, perm, &ad);
4863                 if (err)
4864                         return err;
4865         }
4866
4867         return 0;
4868 }
4869
4870 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4871 static int selinux_socket_connect(struct socket *sock,
4872                                   struct sockaddr *address, int addrlen)
4873 {
4874         int err;
4875         struct sock *sk = sock->sk;
4876
4877         err = selinux_socket_connect_helper(sock, address, addrlen);
4878         if (err)
4879                 return err;
4880
4881         return selinux_netlbl_socket_connect(sk, address);
4882 }
4883
4884 static int selinux_socket_listen(struct socket *sock, int backlog)
4885 {
4886         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4887 }
4888
4889 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4890 {
4891         int err;
4892         struct inode_security_struct *isec;
4893         struct inode_security_struct *newisec;
4894         u16 sclass;
4895         u32 sid;
4896
4897         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4898         if (err)
4899                 return err;
4900
4901         isec = inode_security_novalidate(SOCK_INODE(sock));
4902         spin_lock(&isec->lock);
4903         sclass = isec->sclass;
4904         sid = isec->sid;
4905         spin_unlock(&isec->lock);
4906
4907         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4908         newisec->sclass = sclass;
4909         newisec->sid = sid;
4910         newisec->initialized = LABEL_INITIALIZED;
4911
4912         return 0;
4913 }
4914
4915 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4916                                   int size)
4917 {
4918         return sock_has_perm(sock->sk, SOCKET__WRITE);
4919 }
4920
4921 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4922                                   int size, int flags)
4923 {
4924         return sock_has_perm(sock->sk, SOCKET__READ);
4925 }
4926
4927 static int selinux_socket_getsockname(struct socket *sock)
4928 {
4929         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4930 }
4931
4932 static int selinux_socket_getpeername(struct socket *sock)
4933 {
4934         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4935 }
4936
4937 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4938 {
4939         int err;
4940
4941         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4942         if (err)
4943                 return err;
4944
4945         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4946 }
4947
4948 static int selinux_socket_getsockopt(struct socket *sock, int level,
4949                                      int optname)
4950 {
4951         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4952 }
4953
4954 static int selinux_socket_shutdown(struct socket *sock, int how)
4955 {
4956         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4957 }
4958
4959 static int selinux_socket_unix_stream_connect(struct sock *sock,
4960                                               struct sock *other,
4961                                               struct sock *newsk)
4962 {
4963         struct sk_security_struct *sksec_sock = sock->sk_security;
4964         struct sk_security_struct *sksec_other = other->sk_security;
4965         struct sk_security_struct *sksec_new = newsk->sk_security;
4966         struct common_audit_data ad;
4967         struct lsm_network_audit net = {0,};
4968         int err;
4969
4970         ad.type = LSM_AUDIT_DATA_NET;
4971         ad.u.net = &net;
4972         ad.u.net->sk = other;
4973
4974         err = avc_has_perm(&selinux_state,
4975                            sksec_sock->sid, sksec_other->sid,
4976                            sksec_other->sclass,
4977                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4978         if (err)
4979                 return err;
4980
4981         /* server child socket */
4982         sksec_new->peer_sid = sksec_sock->sid;
4983         err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4984                                     sksec_sock->sid, &sksec_new->sid);
4985         if (err)
4986                 return err;
4987
4988         /* connecting socket */
4989         sksec_sock->peer_sid = sksec_new->sid;
4990
4991         return 0;
4992 }
4993
4994 static int selinux_socket_unix_may_send(struct socket *sock,
4995                                         struct socket *other)
4996 {
4997         struct sk_security_struct *ssec = sock->sk->sk_security;
4998         struct sk_security_struct *osec = other->sk->sk_security;
4999         struct common_audit_data ad;
5000         struct lsm_network_audit net = {0,};
5001
5002         ad.type = LSM_AUDIT_DATA_NET;
5003         ad.u.net = &net;
5004         ad.u.net->sk = other->sk;
5005
5006         return avc_has_perm(&selinux_state,
5007                             ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5008                             &ad);
5009 }
5010
5011 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5012                                     char *addrp, u16 family, u32 peer_sid,
5013                                     struct common_audit_data *ad)
5014 {
5015         int err;
5016         u32 if_sid;
5017         u32 node_sid;
5018
5019         err = sel_netif_sid(ns, ifindex, &if_sid);
5020         if (err)
5021                 return err;
5022         err = avc_has_perm(&selinux_state,
5023                            peer_sid, if_sid,
5024                            SECCLASS_NETIF, NETIF__INGRESS, ad);
5025         if (err)
5026                 return err;
5027
5028         err = sel_netnode_sid(addrp, family, &node_sid);
5029         if (err)
5030                 return err;
5031         return avc_has_perm(&selinux_state,
5032                             peer_sid, node_sid,
5033                             SECCLASS_NODE, NODE__RECVFROM, ad);
5034 }
5035
5036 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5037                                        u16 family)
5038 {
5039         int err = 0;
5040         struct sk_security_struct *sksec = sk->sk_security;
5041         u32 sk_sid = sksec->sid;
5042         struct common_audit_data ad;
5043         struct lsm_network_audit net = {0,};
5044         char *addrp;
5045
5046         ad.type = LSM_AUDIT_DATA_NET;
5047         ad.u.net = &net;
5048         ad.u.net->netif = skb->skb_iif;
5049         ad.u.net->family = family;
5050         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5051         if (err)
5052                 return err;
5053
5054         if (selinux_secmark_enabled()) {
5055                 err = avc_has_perm(&selinux_state,
5056                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5057                                    PACKET__RECV, &ad);
5058                 if (err)
5059                         return err;
5060         }
5061
5062         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5063         if (err)
5064                 return err;
5065         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5066
5067         return err;
5068 }
5069
5070 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5071 {
5072         int err;
5073         struct sk_security_struct *sksec = sk->sk_security;
5074         u16 family = sk->sk_family;
5075         u32 sk_sid = sksec->sid;
5076         struct common_audit_data ad;
5077         struct lsm_network_audit net = {0,};
5078         char *addrp;
5079         u8 secmark_active;
5080         u8 peerlbl_active;
5081
5082         if (family != PF_INET && family != PF_INET6)
5083                 return 0;
5084
5085         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5086         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5087                 family = PF_INET;
5088
5089         /* If any sort of compatibility mode is enabled then handoff processing
5090          * to the selinux_sock_rcv_skb_compat() function to deal with the
5091          * special handling.  We do this in an attempt to keep this function
5092          * as fast and as clean as possible. */
5093         if (!selinux_policycap_netpeer())
5094                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5095
5096         secmark_active = selinux_secmark_enabled();
5097         peerlbl_active = selinux_peerlbl_enabled();
5098         if (!secmark_active && !peerlbl_active)
5099                 return 0;
5100
5101         ad.type = LSM_AUDIT_DATA_NET;
5102         ad.u.net = &net;
5103         ad.u.net->netif = skb->skb_iif;
5104         ad.u.net->family = family;
5105         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5106         if (err)
5107                 return err;
5108
5109         if (peerlbl_active) {
5110                 u32 peer_sid;
5111
5112                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5113                 if (err)
5114                         return err;
5115                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5116                                                addrp, family, peer_sid, &ad);
5117                 if (err) {
5118                         selinux_netlbl_err(skb, family, err, 0);
5119                         return err;
5120                 }
5121                 err = avc_has_perm(&selinux_state,
5122                                    sk_sid, peer_sid, SECCLASS_PEER,
5123                                    PEER__RECV, &ad);
5124                 if (err) {
5125                         selinux_netlbl_err(skb, family, err, 0);
5126                         return err;
5127                 }
5128         }
5129
5130         if (secmark_active) {
5131                 err = avc_has_perm(&selinux_state,
5132                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5133                                    PACKET__RECV, &ad);
5134                 if (err)
5135                         return err;
5136         }
5137
5138         return err;
5139 }
5140
5141 static int selinux_socket_getpeersec_stream(struct socket *sock,
5142                                             sockptr_t optval, sockptr_t optlen,
5143                                             unsigned int len)
5144 {
5145         int err = 0;
5146         char *scontext = NULL;
5147         u32 scontext_len;
5148         struct sk_security_struct *sksec = sock->sk->sk_security;
5149         u32 peer_sid = SECSID_NULL;
5150
5151         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5152             sksec->sclass == SECCLASS_TCP_SOCKET ||
5153             sksec->sclass == SECCLASS_SCTP_SOCKET)
5154                 peer_sid = sksec->peer_sid;
5155         if (peer_sid == SECSID_NULL)
5156                 return -ENOPROTOOPT;
5157
5158         err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5159                                       &scontext_len);
5160         if (err)
5161                 return err;
5162         if (scontext_len > len) {
5163                 err = -ERANGE;
5164                 goto out_len;
5165         }
5166
5167         if (copy_to_sockptr(optval, scontext, scontext_len))
5168                 err = -EFAULT;
5169 out_len:
5170         if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5171                 err = -EFAULT;
5172         kfree(scontext);
5173         return err;
5174 }
5175
5176 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5177 {
5178         u32 peer_secid = SECSID_NULL;
5179         u16 family;
5180         struct inode_security_struct *isec;
5181
5182         if (skb && skb->protocol == htons(ETH_P_IP))
5183                 family = PF_INET;
5184         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5185                 family = PF_INET6;
5186         else if (sock)
5187                 family = sock->sk->sk_family;
5188         else
5189                 goto out;
5190
5191         if (sock && family == PF_UNIX) {
5192                 isec = inode_security_novalidate(SOCK_INODE(sock));
5193                 peer_secid = isec->sid;
5194         } else if (skb)
5195                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5196
5197 out:
5198         *secid = peer_secid;
5199         if (peer_secid == SECSID_NULL)
5200                 return -EINVAL;
5201         return 0;
5202 }
5203
5204 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5205 {
5206         struct sk_security_struct *sksec;
5207
5208         sksec = kzalloc(sizeof(*sksec), priority);
5209         if (!sksec)
5210                 return -ENOMEM;
5211
5212         sksec->peer_sid = SECINITSID_UNLABELED;
5213         sksec->sid = SECINITSID_UNLABELED;
5214         sksec->sclass = SECCLASS_SOCKET;
5215         selinux_netlbl_sk_security_reset(sksec);
5216         sk->sk_security = sksec;
5217
5218         return 0;
5219 }
5220
5221 static void selinux_sk_free_security(struct sock *sk)
5222 {
5223         struct sk_security_struct *sksec = sk->sk_security;
5224
5225         sk->sk_security = NULL;
5226         selinux_netlbl_sk_security_free(sksec);
5227         kfree(sksec);
5228 }
5229
5230 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5231 {
5232         struct sk_security_struct *sksec = sk->sk_security;
5233         struct sk_security_struct *newsksec = newsk->sk_security;
5234
5235         newsksec->sid = sksec->sid;
5236         newsksec->peer_sid = sksec->peer_sid;
5237         newsksec->sclass = sksec->sclass;
5238
5239         selinux_netlbl_sk_security_reset(newsksec);
5240 }
5241
5242 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5243 {
5244         if (!sk)
5245                 *secid = SECINITSID_ANY_SOCKET;
5246         else {
5247                 struct sk_security_struct *sksec = sk->sk_security;
5248
5249                 *secid = sksec->sid;
5250         }
5251 }
5252
5253 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5254 {
5255         struct inode_security_struct *isec =
5256                 inode_security_novalidate(SOCK_INODE(parent));
5257         struct sk_security_struct *sksec = sk->sk_security;
5258
5259         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5260             sk->sk_family == PF_UNIX)
5261                 isec->sid = sksec->sid;
5262         sksec->sclass = isec->sclass;
5263 }
5264
5265 /*
5266  * Determines peer_secid for the asoc and updates socket's peer label
5267  * if it's the first association on the socket.
5268  */
5269 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5270                                           struct sk_buff *skb)
5271 {
5272         struct sock *sk = asoc->base.sk;
5273         u16 family = sk->sk_family;
5274         struct sk_security_struct *sksec = sk->sk_security;
5275         struct common_audit_data ad;
5276         struct lsm_network_audit net = {0,};
5277         int err;
5278
5279         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5280         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5281                 family = PF_INET;
5282
5283         if (selinux_peerlbl_enabled()) {
5284                 asoc->peer_secid = SECSID_NULL;
5285
5286                 /* This will return peer_sid = SECSID_NULL if there are
5287                  * no peer labels, see security_net_peersid_resolve().
5288                  */
5289                 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5290                 if (err)
5291                         return err;
5292
5293                 if (asoc->peer_secid == SECSID_NULL)
5294                         asoc->peer_secid = SECINITSID_UNLABELED;
5295         } else {
5296                 asoc->peer_secid = SECINITSID_UNLABELED;
5297         }
5298
5299         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5300                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5301
5302                 /* Here as first association on socket. As the peer SID
5303                  * was allowed by peer recv (and the netif/node checks),
5304                  * then it is approved by policy and used as the primary
5305                  * peer SID for getpeercon(3).
5306                  */
5307                 sksec->peer_sid = asoc->peer_secid;
5308         } else if (sksec->peer_sid != asoc->peer_secid) {
5309                 /* Other association peer SIDs are checked to enforce
5310                  * consistency among the peer SIDs.
5311                  */
5312                 ad.type = LSM_AUDIT_DATA_NET;
5313                 ad.u.net = &net;
5314                 ad.u.net->sk = asoc->base.sk;
5315                 err = avc_has_perm(&selinux_state,
5316                                    sksec->peer_sid, asoc->peer_secid,
5317                                    sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5318                                    &ad);
5319                 if (err)
5320                         return err;
5321         }
5322         return 0;
5323 }
5324
5325 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5326  * happens on an incoming connect(2), sctp_connectx(3) or
5327  * sctp_sendmsg(3) (with no association already present).
5328  */
5329 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5330                                       struct sk_buff *skb)
5331 {
5332         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5333         u32 conn_sid;
5334         int err;
5335
5336         if (!selinux_policycap_extsockclass())
5337                 return 0;
5338
5339         err = selinux_sctp_process_new_assoc(asoc, skb);
5340         if (err)
5341                 return err;
5342
5343         /* Compute the MLS component for the connection and store
5344          * the information in asoc. This will be used by SCTP TCP type
5345          * sockets and peeled off connections as they cause a new
5346          * socket to be generated. selinux_sctp_sk_clone() will then
5347          * plug this into the new socket.
5348          */
5349         err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5350         if (err)
5351                 return err;
5352
5353         asoc->secid = conn_sid;
5354
5355         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5356         return selinux_netlbl_sctp_assoc_request(asoc, skb);
5357 }
5358
5359 /* Called when SCTP receives a COOKIE ACK chunk as the final
5360  * response to an association request (initited by us).
5361  */
5362 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5363                                           struct sk_buff *skb)
5364 {
5365         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5366
5367         if (!selinux_policycap_extsockclass())
5368                 return 0;
5369
5370         /* Inherit secid from the parent socket - this will be picked up
5371          * by selinux_sctp_sk_clone() if the association gets peeled off
5372          * into a new socket.
5373          */
5374         asoc->secid = sksec->sid;
5375
5376         return selinux_sctp_process_new_assoc(asoc, skb);
5377 }
5378
5379 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5380  * based on their @optname.
5381  */
5382 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5383                                      struct sockaddr *address,
5384                                      int addrlen)
5385 {
5386         int len, err = 0, walk_size = 0;
5387         void *addr_buf;
5388         struct sockaddr *addr;
5389         struct socket *sock;
5390
5391         if (!selinux_policycap_extsockclass())
5392                 return 0;
5393
5394         /* Process one or more addresses that may be IPv4 or IPv6 */
5395         sock = sk->sk_socket;
5396         addr_buf = address;
5397
5398         while (walk_size < addrlen) {
5399                 if (walk_size + sizeof(sa_family_t) > addrlen)
5400                         return -EINVAL;
5401
5402                 addr = addr_buf;
5403                 switch (addr->sa_family) {
5404                 case AF_UNSPEC:
5405                 case AF_INET:
5406                         len = sizeof(struct sockaddr_in);
5407                         break;
5408                 case AF_INET6:
5409                         len = sizeof(struct sockaddr_in6);
5410                         break;
5411                 default:
5412                         return -EINVAL;
5413                 }
5414
5415                 if (walk_size + len > addrlen)
5416                         return -EINVAL;
5417
5418                 err = -EINVAL;
5419                 switch (optname) {
5420                 /* Bind checks */
5421                 case SCTP_PRIMARY_ADDR:
5422                 case SCTP_SET_PEER_PRIMARY_ADDR:
5423                 case SCTP_SOCKOPT_BINDX_ADD:
5424                         err = selinux_socket_bind(sock, addr, len);
5425                         break;
5426                 /* Connect checks */
5427                 case SCTP_SOCKOPT_CONNECTX:
5428                 case SCTP_PARAM_SET_PRIMARY:
5429                 case SCTP_PARAM_ADD_IP:
5430                 case SCTP_SENDMSG_CONNECT:
5431                         err = selinux_socket_connect_helper(sock, addr, len);
5432                         if (err)
5433                                 return err;
5434
5435                         /* As selinux_sctp_bind_connect() is called by the
5436                          * SCTP protocol layer, the socket is already locked,
5437                          * therefore selinux_netlbl_socket_connect_locked()
5438                          * is called here. The situations handled are:
5439                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5440                          * whenever a new IP address is added or when a new
5441                          * primary address is selected.
5442                          * Note that an SCTP connect(2) call happens before
5443                          * the SCTP protocol layer and is handled via
5444                          * selinux_socket_connect().
5445                          */
5446                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5447                         break;
5448                 }
5449
5450                 if (err)
5451                         return err;
5452
5453                 addr_buf += len;
5454                 walk_size += len;
5455         }
5456
5457         return 0;
5458 }
5459
5460 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5461 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5462                                   struct sock *newsk)
5463 {
5464         struct sk_security_struct *sksec = sk->sk_security;
5465         struct sk_security_struct *newsksec = newsk->sk_security;
5466
5467         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5468          * the non-sctp clone version.
5469          */
5470         if (!selinux_policycap_extsockclass())
5471                 return selinux_sk_clone_security(sk, newsk);
5472
5473         newsksec->sid = asoc->secid;
5474         newsksec->peer_sid = asoc->peer_secid;
5475         newsksec->sclass = sksec->sclass;
5476         selinux_netlbl_sctp_sk_clone(sk, newsk);
5477 }
5478
5479 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5480                                      struct request_sock *req)
5481 {
5482         struct sk_security_struct *sksec = sk->sk_security;
5483         int err;
5484         u16 family = req->rsk_ops->family;
5485         u32 connsid;
5486         u32 peersid;
5487
5488         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5489         if (err)
5490                 return err;
5491         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5492         if (err)
5493                 return err;
5494         req->secid = connsid;
5495         req->peer_secid = peersid;
5496
5497         return selinux_netlbl_inet_conn_request(req, family);
5498 }
5499
5500 static void selinux_inet_csk_clone(struct sock *newsk,
5501                                    const struct request_sock *req)
5502 {
5503         struct sk_security_struct *newsksec = newsk->sk_security;
5504
5505         newsksec->sid = req->secid;
5506         newsksec->peer_sid = req->peer_secid;
5507         /* NOTE: Ideally, we should also get the isec->sid for the
5508            new socket in sync, but we don't have the isec available yet.
5509            So we will wait until sock_graft to do it, by which
5510            time it will have been created and available. */
5511
5512         /* We don't need to take any sort of lock here as we are the only
5513          * thread with access to newsksec */
5514         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5515 }
5516
5517 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5518 {
5519         u16 family = sk->sk_family;
5520         struct sk_security_struct *sksec = sk->sk_security;
5521
5522         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5523         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5524                 family = PF_INET;
5525
5526         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5527 }
5528
5529 static int selinux_secmark_relabel_packet(u32 sid)
5530 {
5531         const struct task_security_struct *__tsec;
5532         u32 tsid;
5533
5534         __tsec = selinux_cred(current_cred());
5535         tsid = __tsec->sid;
5536
5537         return avc_has_perm(&selinux_state,
5538                             tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5539                             NULL);
5540 }
5541
5542 static void selinux_secmark_refcount_inc(void)
5543 {
5544         atomic_inc(&selinux_secmark_refcount);
5545 }
5546
5547 static void selinux_secmark_refcount_dec(void)
5548 {
5549         atomic_dec(&selinux_secmark_refcount);
5550 }
5551
5552 static void selinux_req_classify_flow(const struct request_sock *req,
5553                                       struct flowi_common *flic)
5554 {
5555         flic->flowic_secid = req->secid;
5556 }
5557
5558 static int selinux_tun_dev_alloc_security(void **security)
5559 {
5560         struct tun_security_struct *tunsec;
5561
5562         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5563         if (!tunsec)
5564                 return -ENOMEM;
5565         tunsec->sid = current_sid();
5566
5567         *security = tunsec;
5568         return 0;
5569 }
5570
5571 static void selinux_tun_dev_free_security(void *security)
5572 {
5573         kfree(security);
5574 }
5575
5576 static int selinux_tun_dev_create(void)
5577 {
5578         u32 sid = current_sid();
5579
5580         /* we aren't taking into account the "sockcreate" SID since the socket
5581          * that is being created here is not a socket in the traditional sense,
5582          * instead it is a private sock, accessible only to the kernel, and
5583          * representing a wide range of network traffic spanning multiple
5584          * connections unlike traditional sockets - check the TUN driver to
5585          * get a better understanding of why this socket is special */
5586
5587         return avc_has_perm(&selinux_state,
5588                             sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5589                             NULL);
5590 }
5591
5592 static int selinux_tun_dev_attach_queue(void *security)
5593 {
5594         struct tun_security_struct *tunsec = security;
5595
5596         return avc_has_perm(&selinux_state,
5597                             current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5598                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5599 }
5600
5601 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5602 {
5603         struct tun_security_struct *tunsec = security;
5604         struct sk_security_struct *sksec = sk->sk_security;
5605
5606         /* we don't currently perform any NetLabel based labeling here and it
5607          * isn't clear that we would want to do so anyway; while we could apply
5608          * labeling without the support of the TUN user the resulting labeled
5609          * traffic from the other end of the connection would almost certainly
5610          * cause confusion to the TUN user that had no idea network labeling
5611          * protocols were being used */
5612
5613         sksec->sid = tunsec->sid;
5614         sksec->sclass = SECCLASS_TUN_SOCKET;
5615
5616         return 0;
5617 }
5618
5619 static int selinux_tun_dev_open(void *security)
5620 {
5621         struct tun_security_struct *tunsec = security;
5622         u32 sid = current_sid();
5623         int err;
5624
5625         err = avc_has_perm(&selinux_state,
5626                            sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5627                            TUN_SOCKET__RELABELFROM, NULL);
5628         if (err)
5629                 return err;
5630         err = avc_has_perm(&selinux_state,
5631                            sid, sid, SECCLASS_TUN_SOCKET,
5632                            TUN_SOCKET__RELABELTO, NULL);
5633         if (err)
5634                 return err;
5635         tunsec->sid = sid;
5636
5637         return 0;
5638 }
5639
5640 #ifdef CONFIG_NETFILTER
5641
5642 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5643                                        const struct nf_hook_state *state)
5644 {
5645         int ifindex;
5646         u16 family;
5647         char *addrp;
5648         u32 peer_sid;
5649         struct common_audit_data ad;
5650         struct lsm_network_audit net = {0,};
5651         int secmark_active, peerlbl_active;
5652
5653         if (!selinux_policycap_netpeer())
5654                 return NF_ACCEPT;
5655
5656         secmark_active = selinux_secmark_enabled();
5657         peerlbl_active = selinux_peerlbl_enabled();
5658         if (!secmark_active && !peerlbl_active)
5659                 return NF_ACCEPT;
5660
5661         family = state->pf;
5662         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5663                 return NF_DROP;
5664
5665         ifindex = state->in->ifindex;
5666         ad.type = LSM_AUDIT_DATA_NET;
5667         ad.u.net = &net;
5668         ad.u.net->netif = ifindex;
5669         ad.u.net->family = family;
5670         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5671                 return NF_DROP;
5672
5673         if (peerlbl_active) {
5674                 int err;
5675
5676                 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5677                                                addrp, family, peer_sid, &ad);
5678                 if (err) {
5679                         selinux_netlbl_err(skb, family, err, 1);
5680                         return NF_DROP;
5681                 }
5682         }
5683
5684         if (secmark_active)
5685                 if (avc_has_perm(&selinux_state,
5686                                  peer_sid, skb->secmark,
5687                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5688                         return NF_DROP;
5689
5690         if (netlbl_enabled())
5691                 /* we do this in the FORWARD path and not the POST_ROUTING
5692                  * path because we want to make sure we apply the necessary
5693                  * labeling before IPsec is applied so we can leverage AH
5694                  * protection */
5695                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5696                         return NF_DROP;
5697
5698         return NF_ACCEPT;
5699 }
5700
5701 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5702                                       const struct nf_hook_state *state)
5703 {
5704         struct sock *sk;
5705         u32 sid;
5706
5707         if (!netlbl_enabled())
5708                 return NF_ACCEPT;
5709
5710         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5711          * because we want to make sure we apply the necessary labeling
5712          * before IPsec is applied so we can leverage AH protection */
5713         sk = skb->sk;
5714         if (sk) {
5715                 struct sk_security_struct *sksec;
5716
5717                 if (sk_listener(sk))
5718                         /* if the socket is the listening state then this
5719                          * packet is a SYN-ACK packet which means it needs to
5720                          * be labeled based on the connection/request_sock and
5721                          * not the parent socket.  unfortunately, we can't
5722                          * lookup the request_sock yet as it isn't queued on
5723                          * the parent socket until after the SYN-ACK is sent.
5724                          * the "solution" is to simply pass the packet as-is
5725                          * as any IP option based labeling should be copied
5726                          * from the initial connection request (in the IP
5727                          * layer).  it is far from ideal, but until we get a
5728                          * security label in the packet itself this is the
5729                          * best we can do. */
5730                         return NF_ACCEPT;
5731
5732                 /* standard practice, label using the parent socket */
5733                 sksec = sk->sk_security;
5734                 sid = sksec->sid;
5735         } else
5736                 sid = SECINITSID_KERNEL;
5737         if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5738                 return NF_DROP;
5739
5740         return NF_ACCEPT;
5741 }
5742
5743
5744 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5745                                         const struct nf_hook_state *state)
5746 {
5747         struct sock *sk;
5748         struct sk_security_struct *sksec;
5749         struct common_audit_data ad;
5750         struct lsm_network_audit net = {0,};
5751         u8 proto = 0;
5752
5753         sk = skb_to_full_sk(skb);
5754         if (sk == NULL)
5755                 return NF_ACCEPT;
5756         sksec = sk->sk_security;
5757
5758         ad.type = LSM_AUDIT_DATA_NET;
5759         ad.u.net = &net;
5760         ad.u.net->netif = state->out->ifindex;
5761         ad.u.net->family = state->pf;
5762         if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5763                 return NF_DROP;
5764
5765         if (selinux_secmark_enabled())
5766                 if (avc_has_perm(&selinux_state,
5767                                  sksec->sid, skb->secmark,
5768                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5769                         return NF_DROP_ERR(-ECONNREFUSED);
5770
5771         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5772                 return NF_DROP_ERR(-ECONNREFUSED);
5773
5774         return NF_ACCEPT;
5775 }
5776
5777 static unsigned int selinux_ip_postroute(void *priv,
5778                                          struct sk_buff *skb,
5779                                          const struct nf_hook_state *state)
5780 {
5781         u16 family;
5782         u32 secmark_perm;
5783         u32 peer_sid;
5784         int ifindex;
5785         struct sock *sk;
5786         struct common_audit_data ad;
5787         struct lsm_network_audit net = {0,};
5788         char *addrp;
5789         int secmark_active, peerlbl_active;
5790
5791         /* If any sort of compatibility mode is enabled then handoff processing
5792          * to the selinux_ip_postroute_compat() function to deal with the
5793          * special handling.  We do this in an attempt to keep this function
5794          * as fast and as clean as possible. */
5795         if (!selinux_policycap_netpeer())
5796                 return selinux_ip_postroute_compat(skb, state);
5797
5798         secmark_active = selinux_secmark_enabled();
5799         peerlbl_active = selinux_peerlbl_enabled();
5800         if (!secmark_active && !peerlbl_active)
5801                 return NF_ACCEPT;
5802
5803         sk = skb_to_full_sk(skb);
5804
5805 #ifdef CONFIG_XFRM
5806         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5807          * packet transformation so allow the packet to pass without any checks
5808          * since we'll have another chance to perform access control checks
5809          * when the packet is on it's final way out.
5810          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5811          *       is NULL, in this case go ahead and apply access control.
5812          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5813          *       TCP listening state we cannot wait until the XFRM processing
5814          *       is done as we will miss out on the SA label if we do;
5815          *       unfortunately, this means more work, but it is only once per
5816          *       connection. */
5817         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5818             !(sk && sk_listener(sk)))
5819                 return NF_ACCEPT;
5820 #endif
5821
5822         family = state->pf;
5823         if (sk == NULL) {
5824                 /* Without an associated socket the packet is either coming
5825                  * from the kernel or it is being forwarded; check the packet
5826                  * to determine which and if the packet is being forwarded
5827                  * query the packet directly to determine the security label. */
5828                 if (skb->skb_iif) {
5829                         secmark_perm = PACKET__FORWARD_OUT;
5830                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5831                                 return NF_DROP;
5832                 } else {
5833                         secmark_perm = PACKET__SEND;
5834                         peer_sid = SECINITSID_KERNEL;
5835                 }
5836         } else if (sk_listener(sk)) {
5837                 /* Locally generated packet but the associated socket is in the
5838                  * listening state which means this is a SYN-ACK packet.  In
5839                  * this particular case the correct security label is assigned
5840                  * to the connection/request_sock but unfortunately we can't
5841                  * query the request_sock as it isn't queued on the parent
5842                  * socket until after the SYN-ACK packet is sent; the only
5843                  * viable choice is to regenerate the label like we do in
5844                  * selinux_inet_conn_request().  See also selinux_ip_output()
5845                  * for similar problems. */
5846                 u32 skb_sid;
5847                 struct sk_security_struct *sksec;
5848
5849                 sksec = sk->sk_security;
5850                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5851                         return NF_DROP;
5852                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5853                  * and the packet has been through at least one XFRM
5854                  * transformation then we must be dealing with the "final"
5855                  * form of labeled IPsec packet; since we've already applied
5856                  * all of our access controls on this packet we can safely
5857                  * pass the packet. */
5858                 if (skb_sid == SECSID_NULL) {
5859                         switch (family) {
5860                         case PF_INET:
5861                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5862                                         return NF_ACCEPT;
5863                                 break;
5864                         case PF_INET6:
5865                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5866                                         return NF_ACCEPT;
5867                                 break;
5868                         default:
5869                                 return NF_DROP_ERR(-ECONNREFUSED);
5870                         }
5871                 }
5872                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5873                         return NF_DROP;
5874                 secmark_perm = PACKET__SEND;
5875         } else {
5876                 /* Locally generated packet, fetch the security label from the
5877                  * associated socket. */
5878                 struct sk_security_struct *sksec = sk->sk_security;
5879                 peer_sid = sksec->sid;
5880                 secmark_perm = PACKET__SEND;
5881         }
5882
5883         ifindex = state->out->ifindex;
5884         ad.type = LSM_AUDIT_DATA_NET;
5885         ad.u.net = &net;
5886         ad.u.net->netif = ifindex;
5887         ad.u.net->family = family;
5888         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5889                 return NF_DROP;
5890
5891         if (secmark_active)
5892                 if (avc_has_perm(&selinux_state,
5893                                  peer_sid, skb->secmark,
5894                                  SECCLASS_PACKET, secmark_perm, &ad))
5895                         return NF_DROP_ERR(-ECONNREFUSED);
5896
5897         if (peerlbl_active) {
5898                 u32 if_sid;
5899                 u32 node_sid;
5900
5901                 if (sel_netif_sid(state->net, ifindex, &if_sid))
5902                         return NF_DROP;
5903                 if (avc_has_perm(&selinux_state,
5904                                  peer_sid, if_sid,
5905                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5906                         return NF_DROP_ERR(-ECONNREFUSED);
5907
5908                 if (sel_netnode_sid(addrp, family, &node_sid))
5909                         return NF_DROP;
5910                 if (avc_has_perm(&selinux_state,
5911                                  peer_sid, node_sid,
5912                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5913                         return NF_DROP_ERR(-ECONNREFUSED);
5914         }
5915
5916         return NF_ACCEPT;
5917 }
5918 #endif  /* CONFIG_NETFILTER */
5919
5920 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5921 {
5922         int rc = 0;
5923         unsigned int msg_len;
5924         unsigned int data_len = skb->len;
5925         unsigned char *data = skb->data;
5926         struct nlmsghdr *nlh;
5927         struct sk_security_struct *sksec = sk->sk_security;
5928         u16 sclass = sksec->sclass;
5929         u32 perm;
5930
5931         while (data_len >= nlmsg_total_size(0)) {
5932                 nlh = (struct nlmsghdr *)data;
5933
5934                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5935                  *       users which means we can't reject skb's with bogus
5936                  *       length fields; our solution is to follow what
5937                  *       netlink_rcv_skb() does and simply skip processing at
5938                  *       messages with length fields that are clearly junk
5939                  */
5940                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5941                         return 0;
5942
5943                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5944                 if (rc == 0) {
5945                         rc = sock_has_perm(sk, perm);
5946                         if (rc)
5947                                 return rc;
5948                 } else if (rc == -EINVAL) {
5949                         /* -EINVAL is a missing msg/perm mapping */
5950                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5951                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5952                                 " pid=%d comm=%s\n",
5953                                 sk->sk_protocol, nlh->nlmsg_type,
5954                                 secclass_map[sclass - 1].name,
5955                                 task_pid_nr(current), current->comm);
5956                         if (enforcing_enabled(&selinux_state) &&
5957                             !security_get_allow_unknown(&selinux_state))
5958                                 return rc;
5959                         rc = 0;
5960                 } else if (rc == -ENOENT) {
5961                         /* -ENOENT is a missing socket/class mapping, ignore */
5962                         rc = 0;
5963                 } else {
5964                         return rc;
5965                 }
5966
5967                 /* move to the next message after applying netlink padding */
5968                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5969                 if (msg_len >= data_len)
5970                         return 0;
5971                 data_len -= msg_len;
5972                 data += msg_len;
5973         }
5974
5975         return rc;
5976 }
5977
5978 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5979 {
5980         isec->sclass = sclass;
5981         isec->sid = current_sid();
5982 }
5983
5984 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5985                         u32 perms)
5986 {
5987         struct ipc_security_struct *isec;
5988         struct common_audit_data ad;
5989         u32 sid = current_sid();
5990
5991         isec = selinux_ipc(ipc_perms);
5992
5993         ad.type = LSM_AUDIT_DATA_IPC;
5994         ad.u.ipc_id = ipc_perms->key;
5995
5996         return avc_has_perm(&selinux_state,
5997                             sid, isec->sid, isec->sclass, perms, &ad);
5998 }
5999
6000 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6001 {
6002         struct msg_security_struct *msec;
6003
6004         msec = selinux_msg_msg(msg);
6005         msec->sid = SECINITSID_UNLABELED;
6006
6007         return 0;
6008 }
6009
6010 /* message queue security operations */
6011 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6012 {
6013         struct ipc_security_struct *isec;
6014         struct common_audit_data ad;
6015         u32 sid = current_sid();
6016
6017         isec = selinux_ipc(msq);
6018         ipc_init_security(isec, SECCLASS_MSGQ);
6019
6020         ad.type = LSM_AUDIT_DATA_IPC;
6021         ad.u.ipc_id = msq->key;
6022
6023         return avc_has_perm(&selinux_state,
6024                             sid, isec->sid, SECCLASS_MSGQ,
6025                             MSGQ__CREATE, &ad);
6026 }
6027
6028 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6029 {
6030         struct ipc_security_struct *isec;
6031         struct common_audit_data ad;
6032         u32 sid = current_sid();
6033
6034         isec = selinux_ipc(msq);
6035
6036         ad.type = LSM_AUDIT_DATA_IPC;
6037         ad.u.ipc_id = msq->key;
6038
6039         return avc_has_perm(&selinux_state,
6040                             sid, isec->sid, SECCLASS_MSGQ,
6041                             MSGQ__ASSOCIATE, &ad);
6042 }
6043
6044 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6045 {
6046         int err;
6047         int perms;
6048
6049         switch (cmd) {
6050         case IPC_INFO:
6051         case MSG_INFO:
6052                 /* No specific object, just general system-wide information. */
6053                 return avc_has_perm(&selinux_state,
6054                                     current_sid(), SECINITSID_KERNEL,
6055                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6056         case IPC_STAT:
6057         case MSG_STAT:
6058         case MSG_STAT_ANY:
6059                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6060                 break;
6061         case IPC_SET:
6062                 perms = MSGQ__SETATTR;
6063                 break;
6064         case IPC_RMID:
6065                 perms = MSGQ__DESTROY;
6066                 break;
6067         default:
6068                 return 0;
6069         }
6070
6071         err = ipc_has_perm(msq, perms);
6072         return err;
6073 }
6074
6075 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6076 {
6077         struct ipc_security_struct *isec;
6078         struct msg_security_struct *msec;
6079         struct common_audit_data ad;
6080         u32 sid = current_sid();
6081         int rc;
6082
6083         isec = selinux_ipc(msq);
6084         msec = selinux_msg_msg(msg);
6085
6086         /*
6087          * First time through, need to assign label to the message
6088          */
6089         if (msec->sid == SECINITSID_UNLABELED) {
6090                 /*
6091                  * Compute new sid based on current process and
6092                  * message queue this message will be stored in
6093                  */
6094                 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6095                                              SECCLASS_MSG, NULL, &msec->sid);
6096                 if (rc)
6097                         return rc;
6098         }
6099
6100         ad.type = LSM_AUDIT_DATA_IPC;
6101         ad.u.ipc_id = msq->key;
6102
6103         /* Can this process write to the queue? */
6104         rc = avc_has_perm(&selinux_state,
6105                           sid, isec->sid, SECCLASS_MSGQ,
6106                           MSGQ__WRITE, &ad);
6107         if (!rc)
6108                 /* Can this process send the message */
6109                 rc = avc_has_perm(&selinux_state,
6110                                   sid, msec->sid, SECCLASS_MSG,
6111                                   MSG__SEND, &ad);
6112         if (!rc)
6113                 /* Can the message be put in the queue? */
6114                 rc = avc_has_perm(&selinux_state,
6115                                   msec->sid, isec->sid, SECCLASS_MSGQ,
6116                                   MSGQ__ENQUEUE, &ad);
6117
6118         return rc;
6119 }
6120
6121 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6122                                     struct task_struct *target,
6123                                     long type, int mode)
6124 {
6125         struct ipc_security_struct *isec;
6126         struct msg_security_struct *msec;
6127         struct common_audit_data ad;
6128         u32 sid = task_sid_obj(target);
6129         int rc;
6130
6131         isec = selinux_ipc(msq);
6132         msec = selinux_msg_msg(msg);
6133
6134         ad.type = LSM_AUDIT_DATA_IPC;
6135         ad.u.ipc_id = msq->key;
6136
6137         rc = avc_has_perm(&selinux_state,
6138                           sid, isec->sid,
6139                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6140         if (!rc)
6141                 rc = avc_has_perm(&selinux_state,
6142                                   sid, msec->sid,
6143                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6144         return rc;
6145 }
6146
6147 /* Shared Memory security operations */
6148 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6149 {
6150         struct ipc_security_struct *isec;
6151         struct common_audit_data ad;
6152         u32 sid = current_sid();
6153
6154         isec = selinux_ipc(shp);
6155         ipc_init_security(isec, SECCLASS_SHM);
6156
6157         ad.type = LSM_AUDIT_DATA_IPC;
6158         ad.u.ipc_id = shp->key;
6159
6160         return avc_has_perm(&selinux_state,
6161                             sid, isec->sid, SECCLASS_SHM,
6162                             SHM__CREATE, &ad);
6163 }
6164
6165 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6166 {
6167         struct ipc_security_struct *isec;
6168         struct common_audit_data ad;
6169         u32 sid = current_sid();
6170
6171         isec = selinux_ipc(shp);
6172
6173         ad.type = LSM_AUDIT_DATA_IPC;
6174         ad.u.ipc_id = shp->key;
6175
6176         return avc_has_perm(&selinux_state,
6177                             sid, isec->sid, SECCLASS_SHM,
6178                             SHM__ASSOCIATE, &ad);
6179 }
6180
6181 /* Note, at this point, shp is locked down */
6182 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6183 {
6184         int perms;
6185         int err;
6186
6187         switch (cmd) {
6188         case IPC_INFO:
6189         case SHM_INFO:
6190                 /* No specific object, just general system-wide information. */
6191                 return avc_has_perm(&selinux_state,
6192                                     current_sid(), SECINITSID_KERNEL,
6193                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6194         case IPC_STAT:
6195         case SHM_STAT:
6196         case SHM_STAT_ANY:
6197                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6198                 break;
6199         case IPC_SET:
6200                 perms = SHM__SETATTR;
6201                 break;
6202         case SHM_LOCK:
6203         case SHM_UNLOCK:
6204                 perms = SHM__LOCK;
6205                 break;
6206         case IPC_RMID:
6207                 perms = SHM__DESTROY;
6208                 break;
6209         default:
6210                 return 0;
6211         }
6212
6213         err = ipc_has_perm(shp, perms);
6214         return err;
6215 }
6216
6217 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6218                              char __user *shmaddr, int shmflg)
6219 {
6220         u32 perms;
6221
6222         if (shmflg & SHM_RDONLY)
6223                 perms = SHM__READ;
6224         else
6225                 perms = SHM__READ | SHM__WRITE;
6226
6227         return ipc_has_perm(shp, perms);
6228 }
6229
6230 /* Semaphore security operations */
6231 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6232 {
6233         struct ipc_security_struct *isec;
6234         struct common_audit_data ad;
6235         u32 sid = current_sid();
6236
6237         isec = selinux_ipc(sma);
6238         ipc_init_security(isec, SECCLASS_SEM);
6239
6240         ad.type = LSM_AUDIT_DATA_IPC;
6241         ad.u.ipc_id = sma->key;
6242
6243         return avc_has_perm(&selinux_state,
6244                             sid, isec->sid, SECCLASS_SEM,
6245                             SEM__CREATE, &ad);
6246 }
6247
6248 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6249 {
6250         struct ipc_security_struct *isec;
6251         struct common_audit_data ad;
6252         u32 sid = current_sid();
6253
6254         isec = selinux_ipc(sma);
6255
6256         ad.type = LSM_AUDIT_DATA_IPC;
6257         ad.u.ipc_id = sma->key;
6258
6259         return avc_has_perm(&selinux_state,
6260                             sid, isec->sid, SECCLASS_SEM,
6261                             SEM__ASSOCIATE, &ad);
6262 }
6263
6264 /* Note, at this point, sma is locked down */
6265 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6266 {
6267         int err;
6268         u32 perms;
6269
6270         switch (cmd) {
6271         case IPC_INFO:
6272         case SEM_INFO:
6273                 /* No specific object, just general system-wide information. */
6274                 return avc_has_perm(&selinux_state,
6275                                     current_sid(), SECINITSID_KERNEL,
6276                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6277         case GETPID:
6278         case GETNCNT:
6279         case GETZCNT:
6280                 perms = SEM__GETATTR;
6281                 break;
6282         case GETVAL:
6283         case GETALL:
6284                 perms = SEM__READ;
6285                 break;
6286         case SETVAL:
6287         case SETALL:
6288                 perms = SEM__WRITE;
6289                 break;
6290         case IPC_RMID:
6291                 perms = SEM__DESTROY;
6292                 break;
6293         case IPC_SET:
6294                 perms = SEM__SETATTR;
6295                 break;
6296         case IPC_STAT:
6297         case SEM_STAT:
6298         case SEM_STAT_ANY:
6299                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6300                 break;
6301         default:
6302                 return 0;
6303         }
6304
6305         err = ipc_has_perm(sma, perms);
6306         return err;
6307 }
6308
6309 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6310                              struct sembuf *sops, unsigned nsops, int alter)
6311 {
6312         u32 perms;
6313
6314         if (alter)
6315                 perms = SEM__READ | SEM__WRITE;
6316         else
6317                 perms = SEM__READ;
6318
6319         return ipc_has_perm(sma, perms);
6320 }
6321
6322 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6323 {
6324         u32 av = 0;
6325
6326         av = 0;
6327         if (flag & S_IRUGO)
6328                 av |= IPC__UNIX_READ;
6329         if (flag & S_IWUGO)
6330                 av |= IPC__UNIX_WRITE;
6331
6332         if (av == 0)
6333                 return 0;
6334
6335         return ipc_has_perm(ipcp, av);
6336 }
6337
6338 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6339 {
6340         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6341         *secid = isec->sid;
6342 }
6343
6344 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6345 {
6346         if (inode)
6347                 inode_doinit_with_dentry(inode, dentry);
6348 }
6349
6350 static int selinux_getprocattr(struct task_struct *p,
6351                                const char *name, char **value)
6352 {
6353         const struct task_security_struct *__tsec;
6354         u32 sid;
6355         int error;
6356         unsigned len;
6357
6358         rcu_read_lock();
6359         __tsec = selinux_cred(__task_cred(p));
6360
6361         if (current != p) {
6362                 error = avc_has_perm(&selinux_state,
6363                                      current_sid(), __tsec->sid,
6364                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6365                 if (error)
6366                         goto bad;
6367         }
6368
6369         if (!strcmp(name, "current"))
6370                 sid = __tsec->sid;
6371         else if (!strcmp(name, "prev"))
6372                 sid = __tsec->osid;
6373         else if (!strcmp(name, "exec"))
6374                 sid = __tsec->exec_sid;
6375         else if (!strcmp(name, "fscreate"))
6376                 sid = __tsec->create_sid;
6377         else if (!strcmp(name, "keycreate"))
6378                 sid = __tsec->keycreate_sid;
6379         else if (!strcmp(name, "sockcreate"))
6380                 sid = __tsec->sockcreate_sid;
6381         else {
6382                 error = -EINVAL;
6383                 goto bad;
6384         }
6385         rcu_read_unlock();
6386
6387         if (!sid)
6388                 return 0;
6389
6390         error = security_sid_to_context(&selinux_state, sid, value, &len);
6391         if (error)
6392                 return error;
6393         return len;
6394
6395 bad:
6396         rcu_read_unlock();
6397         return error;
6398 }
6399
6400 static int selinux_setprocattr(const char *name, void *value, size_t size)
6401 {
6402         struct task_security_struct *tsec;
6403         struct cred *new;
6404         u32 mysid = current_sid(), sid = 0, ptsid;
6405         int error;
6406         char *str = value;
6407
6408         /*
6409          * Basic control over ability to set these attributes at all.
6410          */
6411         if (!strcmp(name, "exec"))
6412                 error = avc_has_perm(&selinux_state,
6413                                      mysid, mysid, SECCLASS_PROCESS,
6414                                      PROCESS__SETEXEC, NULL);
6415         else if (!strcmp(name, "fscreate"))
6416                 error = avc_has_perm(&selinux_state,
6417                                      mysid, mysid, SECCLASS_PROCESS,
6418                                      PROCESS__SETFSCREATE, NULL);
6419         else if (!strcmp(name, "keycreate"))
6420                 error = avc_has_perm(&selinux_state,
6421                                      mysid, mysid, SECCLASS_PROCESS,
6422                                      PROCESS__SETKEYCREATE, NULL);
6423         else if (!strcmp(name, "sockcreate"))
6424                 error = avc_has_perm(&selinux_state,
6425                                      mysid, mysid, SECCLASS_PROCESS,
6426                                      PROCESS__SETSOCKCREATE, NULL);
6427         else if (!strcmp(name, "current"))
6428                 error = avc_has_perm(&selinux_state,
6429                                      mysid, mysid, SECCLASS_PROCESS,
6430                                      PROCESS__SETCURRENT, NULL);
6431         else
6432                 error = -EINVAL;
6433         if (error)
6434                 return error;
6435
6436         /* Obtain a SID for the context, if one was specified. */
6437         if (size && str[0] && str[0] != '\n') {
6438                 if (str[size-1] == '\n') {
6439                         str[size-1] = 0;
6440                         size--;
6441                 }
6442                 error = security_context_to_sid(&selinux_state, value, size,
6443                                                 &sid, GFP_KERNEL);
6444                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6445                         if (!has_cap_mac_admin(true)) {
6446                                 struct audit_buffer *ab;
6447                                 size_t audit_size;
6448
6449                                 /* We strip a nul only if it is at the end, otherwise the
6450                                  * context contains a nul and we should audit that */
6451                                 if (str[size - 1] == '\0')
6452                                         audit_size = size - 1;
6453                                 else
6454                                         audit_size = size;
6455                                 ab = audit_log_start(audit_context(),
6456                                                      GFP_ATOMIC,
6457                                                      AUDIT_SELINUX_ERR);
6458                                 if (!ab)
6459                                         return error;
6460                                 audit_log_format(ab, "op=fscreate invalid_context=");
6461                                 audit_log_n_untrustedstring(ab, value, audit_size);
6462                                 audit_log_end(ab);
6463
6464                                 return error;
6465                         }
6466                         error = security_context_to_sid_force(
6467                                                       &selinux_state,
6468                                                       value, size, &sid);
6469                 }
6470                 if (error)
6471                         return error;
6472         }
6473
6474         new = prepare_creds();
6475         if (!new)
6476                 return -ENOMEM;
6477
6478         /* Permission checking based on the specified context is
6479            performed during the actual operation (execve,
6480            open/mkdir/...), when we know the full context of the
6481            operation.  See selinux_bprm_creds_for_exec for the execve
6482            checks and may_create for the file creation checks. The
6483            operation will then fail if the context is not permitted. */
6484         tsec = selinux_cred(new);
6485         if (!strcmp(name, "exec")) {
6486                 tsec->exec_sid = sid;
6487         } else if (!strcmp(name, "fscreate")) {
6488                 tsec->create_sid = sid;
6489         } else if (!strcmp(name, "keycreate")) {
6490                 if (sid) {
6491                         error = avc_has_perm(&selinux_state, mysid, sid,
6492                                              SECCLASS_KEY, KEY__CREATE, NULL);
6493                         if (error)
6494                                 goto abort_change;
6495                 }
6496                 tsec->keycreate_sid = sid;
6497         } else if (!strcmp(name, "sockcreate")) {
6498                 tsec->sockcreate_sid = sid;
6499         } else if (!strcmp(name, "current")) {
6500                 error = -EINVAL;
6501                 if (sid == 0)
6502                         goto abort_change;
6503
6504                 /* Only allow single threaded processes to change context */
6505                 if (!current_is_single_threaded()) {
6506                         error = security_bounded_transition(&selinux_state,
6507                                                             tsec->sid, sid);
6508                         if (error)
6509                                 goto abort_change;
6510                 }
6511
6512                 /* Check permissions for the transition. */
6513                 error = avc_has_perm(&selinux_state,
6514                                      tsec->sid, sid, SECCLASS_PROCESS,
6515                                      PROCESS__DYNTRANSITION, NULL);
6516                 if (error)
6517                         goto abort_change;
6518
6519                 /* Check for ptracing, and update the task SID if ok.
6520                    Otherwise, leave SID unchanged and fail. */
6521                 ptsid = ptrace_parent_sid();
6522                 if (ptsid != 0) {
6523                         error = avc_has_perm(&selinux_state,
6524                                              ptsid, sid, SECCLASS_PROCESS,
6525                                              PROCESS__PTRACE, NULL);
6526                         if (error)
6527                                 goto abort_change;
6528                 }
6529
6530                 tsec->sid = sid;
6531         } else {
6532                 error = -EINVAL;
6533                 goto abort_change;
6534         }
6535
6536         commit_creds(new);
6537         return size;
6538
6539 abort_change:
6540         abort_creds(new);
6541         return error;
6542 }
6543
6544 static int selinux_ismaclabel(const char *name)
6545 {
6546         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6547 }
6548
6549 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6550 {
6551         return security_sid_to_context(&selinux_state, secid,
6552                                        secdata, seclen);
6553 }
6554
6555 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6556 {
6557         return security_context_to_sid(&selinux_state, secdata, seclen,
6558                                        secid, GFP_KERNEL);
6559 }
6560
6561 static void selinux_release_secctx(char *secdata, u32 seclen)
6562 {
6563         kfree(secdata);
6564 }
6565
6566 static void selinux_inode_invalidate_secctx(struct inode *inode)
6567 {
6568         struct inode_security_struct *isec = selinux_inode(inode);
6569
6570         spin_lock(&isec->lock);
6571         isec->initialized = LABEL_INVALID;
6572         spin_unlock(&isec->lock);
6573 }
6574
6575 /*
6576  *      called with inode->i_mutex locked
6577  */
6578 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6579 {
6580         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6581                                            ctx, ctxlen, 0);
6582         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6583         return rc == -EOPNOTSUPP ? 0 : rc;
6584 }
6585
6586 /*
6587  *      called with inode->i_mutex locked
6588  */
6589 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6590 {
6591         return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SELINUX,
6592                                      ctx, ctxlen, 0);
6593 }
6594
6595 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6596 {
6597         int len = 0;
6598         len = selinux_inode_getsecurity(&init_user_ns, inode,
6599                                         XATTR_SELINUX_SUFFIX, ctx, true);
6600         if (len < 0)
6601                 return len;
6602         *ctxlen = len;
6603         return 0;
6604 }
6605 #ifdef CONFIG_KEYS
6606
6607 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6608                              unsigned long flags)
6609 {
6610         const struct task_security_struct *tsec;
6611         struct key_security_struct *ksec;
6612
6613         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6614         if (!ksec)
6615                 return -ENOMEM;
6616
6617         tsec = selinux_cred(cred);
6618         if (tsec->keycreate_sid)
6619                 ksec->sid = tsec->keycreate_sid;
6620         else
6621                 ksec->sid = tsec->sid;
6622
6623         k->security = ksec;
6624         return 0;
6625 }
6626
6627 static void selinux_key_free(struct key *k)
6628 {
6629         struct key_security_struct *ksec = k->security;
6630
6631         k->security = NULL;
6632         kfree(ksec);
6633 }
6634
6635 static int selinux_key_permission(key_ref_t key_ref,
6636                                   const struct cred *cred,
6637                                   enum key_need_perm need_perm)
6638 {
6639         struct key *key;
6640         struct key_security_struct *ksec;
6641         u32 perm, sid;
6642
6643         switch (need_perm) {
6644         case KEY_NEED_VIEW:
6645                 perm = KEY__VIEW;
6646                 break;
6647         case KEY_NEED_READ:
6648                 perm = KEY__READ;
6649                 break;
6650         case KEY_NEED_WRITE:
6651                 perm = KEY__WRITE;
6652                 break;
6653         case KEY_NEED_SEARCH:
6654                 perm = KEY__SEARCH;
6655                 break;
6656         case KEY_NEED_LINK:
6657                 perm = KEY__LINK;
6658                 break;
6659         case KEY_NEED_SETATTR:
6660                 perm = KEY__SETATTR;
6661                 break;
6662         case KEY_NEED_UNLINK:
6663         case KEY_SYSADMIN_OVERRIDE:
6664         case KEY_AUTHTOKEN_OVERRIDE:
6665         case KEY_DEFER_PERM_CHECK:
6666                 return 0;
6667         default:
6668                 WARN_ON(1);
6669                 return -EPERM;
6670
6671         }
6672
6673         sid = cred_sid(cred);
6674         key = key_ref_to_ptr(key_ref);
6675         ksec = key->security;
6676
6677         return avc_has_perm(&selinux_state,
6678                             sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6679 }
6680
6681 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6682 {
6683         struct key_security_struct *ksec = key->security;
6684         char *context = NULL;
6685         unsigned len;
6686         int rc;
6687
6688         rc = security_sid_to_context(&selinux_state, ksec->sid,
6689                                      &context, &len);
6690         if (!rc)
6691                 rc = len;
6692         *_buffer = context;
6693         return rc;
6694 }
6695
6696 #ifdef CONFIG_KEY_NOTIFICATIONS
6697 static int selinux_watch_key(struct key *key)
6698 {
6699         struct key_security_struct *ksec = key->security;
6700         u32 sid = current_sid();
6701
6702         return avc_has_perm(&selinux_state,
6703                             sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6704 }
6705 #endif
6706 #endif
6707
6708 #ifdef CONFIG_SECURITY_INFINIBAND
6709 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6710 {
6711         struct common_audit_data ad;
6712         int err;
6713         u32 sid = 0;
6714         struct ib_security_struct *sec = ib_sec;
6715         struct lsm_ibpkey_audit ibpkey;
6716
6717         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6718         if (err)
6719                 return err;
6720
6721         ad.type = LSM_AUDIT_DATA_IBPKEY;
6722         ibpkey.subnet_prefix = subnet_prefix;
6723         ibpkey.pkey = pkey_val;
6724         ad.u.ibpkey = &ibpkey;
6725         return avc_has_perm(&selinux_state,
6726                             sec->sid, sid,
6727                             SECCLASS_INFINIBAND_PKEY,
6728                             INFINIBAND_PKEY__ACCESS, &ad);
6729 }
6730
6731 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6732                                             u8 port_num)
6733 {
6734         struct common_audit_data ad;
6735         int err;
6736         u32 sid = 0;
6737         struct ib_security_struct *sec = ib_sec;
6738         struct lsm_ibendport_audit ibendport;
6739
6740         err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6741                                       &sid);
6742
6743         if (err)
6744                 return err;
6745
6746         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6747         ibendport.dev_name = dev_name;
6748         ibendport.port = port_num;
6749         ad.u.ibendport = &ibendport;
6750         return avc_has_perm(&selinux_state,
6751                             sec->sid, sid,
6752                             SECCLASS_INFINIBAND_ENDPORT,
6753                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6754 }
6755
6756 static int selinux_ib_alloc_security(void **ib_sec)
6757 {
6758         struct ib_security_struct *sec;
6759
6760         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6761         if (!sec)
6762                 return -ENOMEM;
6763         sec->sid = current_sid();
6764
6765         *ib_sec = sec;
6766         return 0;
6767 }
6768
6769 static void selinux_ib_free_security(void *ib_sec)
6770 {
6771         kfree(ib_sec);
6772 }
6773 #endif
6774
6775 #ifdef CONFIG_BPF_SYSCALL
6776 static int selinux_bpf(int cmd, union bpf_attr *attr,
6777                                      unsigned int size)
6778 {
6779         u32 sid = current_sid();
6780         int ret;
6781
6782         switch (cmd) {
6783         case BPF_MAP_CREATE:
6784                 ret = avc_has_perm(&selinux_state,
6785                                    sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6786                                    NULL);
6787                 break;
6788         case BPF_PROG_LOAD:
6789                 ret = avc_has_perm(&selinux_state,
6790                                    sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6791                                    NULL);
6792                 break;
6793         default:
6794                 ret = 0;
6795                 break;
6796         }
6797
6798         return ret;
6799 }
6800
6801 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6802 {
6803         u32 av = 0;
6804
6805         if (fmode & FMODE_READ)
6806                 av |= BPF__MAP_READ;
6807         if (fmode & FMODE_WRITE)
6808                 av |= BPF__MAP_WRITE;
6809         return av;
6810 }
6811
6812 /* This function will check the file pass through unix socket or binder to see
6813  * if it is a bpf related object. And apply corresponding checks on the bpf
6814  * object based on the type. The bpf maps and programs, not like other files and
6815  * socket, are using a shared anonymous inode inside the kernel as their inode.
6816  * So checking that inode cannot identify if the process have privilege to
6817  * access the bpf object and that's why we have to add this additional check in
6818  * selinux_file_receive and selinux_binder_transfer_files.
6819  */
6820 static int bpf_fd_pass(struct file *file, u32 sid)
6821 {
6822         struct bpf_security_struct *bpfsec;
6823         struct bpf_prog *prog;
6824         struct bpf_map *map;
6825         int ret;
6826
6827         if (file->f_op == &bpf_map_fops) {
6828                 map = file->private_data;
6829                 bpfsec = map->security;
6830                 ret = avc_has_perm(&selinux_state,
6831                                    sid, bpfsec->sid, SECCLASS_BPF,
6832                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6833                 if (ret)
6834                         return ret;
6835         } else if (file->f_op == &bpf_prog_fops) {
6836                 prog = file->private_data;
6837                 bpfsec = prog->aux->security;
6838                 ret = avc_has_perm(&selinux_state,
6839                                    sid, bpfsec->sid, SECCLASS_BPF,
6840                                    BPF__PROG_RUN, NULL);
6841                 if (ret)
6842                         return ret;
6843         }
6844         return 0;
6845 }
6846
6847 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6848 {
6849         u32 sid = current_sid();
6850         struct bpf_security_struct *bpfsec;
6851
6852         bpfsec = map->security;
6853         return avc_has_perm(&selinux_state,
6854                             sid, bpfsec->sid, SECCLASS_BPF,
6855                             bpf_map_fmode_to_av(fmode), NULL);
6856 }
6857
6858 static int selinux_bpf_prog(struct bpf_prog *prog)
6859 {
6860         u32 sid = current_sid();
6861         struct bpf_security_struct *bpfsec;
6862
6863         bpfsec = prog->aux->security;
6864         return avc_has_perm(&selinux_state,
6865                             sid, bpfsec->sid, SECCLASS_BPF,
6866                             BPF__PROG_RUN, NULL);
6867 }
6868
6869 static int selinux_bpf_map_alloc(struct bpf_map *map)
6870 {
6871         struct bpf_security_struct *bpfsec;
6872
6873         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6874         if (!bpfsec)
6875                 return -ENOMEM;
6876
6877         bpfsec->sid = current_sid();
6878         map->security = bpfsec;
6879
6880         return 0;
6881 }
6882
6883 static void selinux_bpf_map_free(struct bpf_map *map)
6884 {
6885         struct bpf_security_struct *bpfsec = map->security;
6886
6887         map->security = NULL;
6888         kfree(bpfsec);
6889 }
6890
6891 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6892 {
6893         struct bpf_security_struct *bpfsec;
6894
6895         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6896         if (!bpfsec)
6897                 return -ENOMEM;
6898
6899         bpfsec->sid = current_sid();
6900         aux->security = bpfsec;
6901
6902         return 0;
6903 }
6904
6905 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6906 {
6907         struct bpf_security_struct *bpfsec = aux->security;
6908
6909         aux->security = NULL;
6910         kfree(bpfsec);
6911 }
6912 #endif
6913
6914 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
6915         .lbs_cred = sizeof(struct task_security_struct),
6916         .lbs_file = sizeof(struct file_security_struct),
6917         .lbs_inode = sizeof(struct inode_security_struct),
6918         .lbs_ipc = sizeof(struct ipc_security_struct),
6919         .lbs_msg_msg = sizeof(struct msg_security_struct),
6920         .lbs_superblock = sizeof(struct superblock_security_struct),
6921 };
6922
6923 #ifdef CONFIG_PERF_EVENTS
6924 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6925 {
6926         u32 requested, sid = current_sid();
6927
6928         if (type == PERF_SECURITY_OPEN)
6929                 requested = PERF_EVENT__OPEN;
6930         else if (type == PERF_SECURITY_CPU)
6931                 requested = PERF_EVENT__CPU;
6932         else if (type == PERF_SECURITY_KERNEL)
6933                 requested = PERF_EVENT__KERNEL;
6934         else if (type == PERF_SECURITY_TRACEPOINT)
6935                 requested = PERF_EVENT__TRACEPOINT;
6936         else
6937                 return -EINVAL;
6938
6939         return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT,
6940                             requested, NULL);
6941 }
6942
6943 static int selinux_perf_event_alloc(struct perf_event *event)
6944 {
6945         struct perf_event_security_struct *perfsec;
6946
6947         perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
6948         if (!perfsec)
6949                 return -ENOMEM;
6950
6951         perfsec->sid = current_sid();
6952         event->security = perfsec;
6953
6954         return 0;
6955 }
6956
6957 static void selinux_perf_event_free(struct perf_event *event)
6958 {
6959         struct perf_event_security_struct *perfsec = event->security;
6960
6961         event->security = NULL;
6962         kfree(perfsec);
6963 }
6964
6965 static int selinux_perf_event_read(struct perf_event *event)
6966 {
6967         struct perf_event_security_struct *perfsec = event->security;
6968         u32 sid = current_sid();
6969
6970         return avc_has_perm(&selinux_state, sid, perfsec->sid,
6971                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
6972 }
6973
6974 static int selinux_perf_event_write(struct perf_event *event)
6975 {
6976         struct perf_event_security_struct *perfsec = event->security;
6977         u32 sid = current_sid();
6978
6979         return avc_has_perm(&selinux_state, sid, perfsec->sid,
6980                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
6981 }
6982 #endif
6983
6984 #ifdef CONFIG_IO_URING
6985 /**
6986  * selinux_uring_override_creds - check the requested cred override
6987  * @new: the target creds
6988  *
6989  * Check to see if the current task is allowed to override it's credentials
6990  * to service an io_uring operation.
6991  */
6992 static int selinux_uring_override_creds(const struct cred *new)
6993 {
6994         return avc_has_perm(&selinux_state, current_sid(), cred_sid(new),
6995                             SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
6996 }
6997
6998 /**
6999  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7000  *
7001  * Check to see if the current task is allowed to create a new io_uring
7002  * kernel polling thread.
7003  */
7004 static int selinux_uring_sqpoll(void)
7005 {
7006         int sid = current_sid();
7007
7008         return avc_has_perm(&selinux_state, sid, sid,
7009                             SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7010 }
7011
7012 /**
7013  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7014  * @ioucmd: the io_uring command structure
7015  *
7016  * Check to see if the current domain is allowed to execute an
7017  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7018  *
7019  */
7020 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7021 {
7022         struct file *file = ioucmd->file;
7023         struct inode *inode = file_inode(file);
7024         struct inode_security_struct *isec = selinux_inode(inode);
7025         struct common_audit_data ad;
7026
7027         ad.type = LSM_AUDIT_DATA_FILE;
7028         ad.u.file = file;
7029
7030         return avc_has_perm(&selinux_state, current_sid(), isec->sid,
7031                             SECCLASS_IO_URING, IO_URING__CMD, &ad);
7032 }
7033 #endif /* CONFIG_IO_URING */
7034
7035 /*
7036  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7037  * 1. any hooks that don't belong to (2.) or (3.) below,
7038  * 2. hooks that both access structures allocated by other hooks, and allocate
7039  *    structures that can be later accessed by other hooks (mostly "cloning"
7040  *    hooks),
7041  * 3. hooks that only allocate structures that can be later accessed by other
7042  *    hooks ("allocating" hooks).
7043  *
7044  * Please follow block comment delimiters in the list to keep this order.
7045  *
7046  * This ordering is needed for SELinux runtime disable to work at least somewhat
7047  * safely. Breaking the ordering rules above might lead to NULL pointer derefs
7048  * when disabling SELinux at runtime.
7049  */
7050 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
7051         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7052         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7053         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7054         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7055
7056         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7057         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7058         LSM_HOOK_INIT(capget, selinux_capget),
7059         LSM_HOOK_INIT(capset, selinux_capset),
7060         LSM_HOOK_INIT(capable, selinux_capable),
7061         LSM_HOOK_INIT(quotactl, selinux_quotactl),
7062         LSM_HOOK_INIT(quota_on, selinux_quota_on),
7063         LSM_HOOK_INIT(syslog, selinux_syslog),
7064         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7065
7066         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7067
7068         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7069         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7070         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7071
7072         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7073         LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7074         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7075         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7076         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7077         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7078         LSM_HOOK_INIT(sb_mount, selinux_mount),
7079         LSM_HOOK_INIT(sb_umount, selinux_umount),
7080         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7081         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7082
7083         LSM_HOOK_INIT(move_mount, selinux_move_mount),
7084
7085         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7086         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7087
7088         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7089         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7090         LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7091         LSM_HOOK_INIT(inode_create, selinux_inode_create),
7092         LSM_HOOK_INIT(inode_link, selinux_inode_link),
7093         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7094         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7095         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7096         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7097         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7098         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7099         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7100         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7101         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7102         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7103         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7104         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7105         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7106         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7107         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7108         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7109         LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7110         LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7111         LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7112         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7113         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7114         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7115         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7116         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7117         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7118         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7119
7120         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7121
7122         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7123         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7124         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7125         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7126         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7127         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7128         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7129         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7130         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7131         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7132         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7133
7134         LSM_HOOK_INIT(file_open, selinux_file_open),
7135
7136         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7137         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7138         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7139         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7140         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7141         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7142         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7143         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7144         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7145         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7146         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7147         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7148         LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj),
7149         LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7150         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7151         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7152         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7153         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7154         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7155         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7156         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7157         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7158         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7159         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7160         LSM_HOOK_INIT(userns_create, selinux_userns_create),
7161
7162         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7163         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7164
7165         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7166         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7167         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7168         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7169
7170         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7171         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7172         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7173
7174         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7175         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7176         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7177
7178         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7179
7180         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7181         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7182
7183         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7184         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7185         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7186         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7187         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7188         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7189
7190         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7191         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7192
7193         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7194         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7195         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7196         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7197         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7198         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7199         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7200         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7201         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7202         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7203         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7204         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7205         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7206         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7207         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7208         LSM_HOOK_INIT(socket_getpeersec_stream,
7209                         selinux_socket_getpeersec_stream),
7210         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7211         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7212         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7213         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7214         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7215         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7216         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7217         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7218         LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7219         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7220         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7221         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7222         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7223         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7224         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7225         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7226         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7227         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7228         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7229         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7230         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7231 #ifdef CONFIG_SECURITY_INFINIBAND
7232         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7233         LSM_HOOK_INIT(ib_endport_manage_subnet,
7234                       selinux_ib_endport_manage_subnet),
7235         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7236 #endif
7237 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7238         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7239         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7240         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7241         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7242         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7243         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7244                         selinux_xfrm_state_pol_flow_match),
7245         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7246 #endif
7247
7248 #ifdef CONFIG_KEYS
7249         LSM_HOOK_INIT(key_free, selinux_key_free),
7250         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7251         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7252 #ifdef CONFIG_KEY_NOTIFICATIONS
7253         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7254 #endif
7255 #endif
7256
7257 #ifdef CONFIG_AUDIT
7258         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7259         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7260         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7261 #endif
7262
7263 #ifdef CONFIG_BPF_SYSCALL
7264         LSM_HOOK_INIT(bpf, selinux_bpf),
7265         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7266         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7267         LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7268         LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7269 #endif
7270
7271 #ifdef CONFIG_PERF_EVENTS
7272         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7273         LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7274         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7275         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7276 #endif
7277
7278 #ifdef CONFIG_IO_URING
7279         LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7280         LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7281         LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7282 #endif
7283
7284         /*
7285          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7286          */
7287         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7288         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7289         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7290 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7291         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7292 #endif
7293
7294         /*
7295          * PUT "ALLOCATING" HOOKS HERE
7296          */
7297         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7298         LSM_HOOK_INIT(msg_queue_alloc_security,
7299                       selinux_msg_queue_alloc_security),
7300         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7301         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7302         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7303         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7304         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7305         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7306         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7307         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7308 #ifdef CONFIG_SECURITY_INFINIBAND
7309         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7310 #endif
7311 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7312         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7313         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7314         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7315                       selinux_xfrm_state_alloc_acquire),
7316 #endif
7317 #ifdef CONFIG_KEYS
7318         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7319 #endif
7320 #ifdef CONFIG_AUDIT
7321         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7322 #endif
7323 #ifdef CONFIG_BPF_SYSCALL
7324         LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7325         LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7326 #endif
7327 #ifdef CONFIG_PERF_EVENTS
7328         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7329 #endif
7330 };
7331
7332 static __init int selinux_init(void)
7333 {
7334         pr_info("SELinux:  Initializing.\n");
7335
7336         memset(&selinux_state, 0, sizeof(selinux_state));
7337         enforcing_set(&selinux_state, selinux_enforcing_boot);
7338         if (CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE)
7339                 pr_err("SELinux: CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE is non-zero.  This is deprecated and will be rejected in a future kernel release.\n");
7340         checkreqprot_set(&selinux_state, selinux_checkreqprot_boot);
7341         selinux_avc_init(&selinux_state.avc);
7342         mutex_init(&selinux_state.status_lock);
7343         mutex_init(&selinux_state.policy_mutex);
7344
7345         /* Set the security state for the initial task. */
7346         cred_init_security();
7347
7348         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7349
7350         avc_init();
7351
7352         avtab_cache_init();
7353
7354         ebitmap_cache_init();
7355
7356         hashtab_cache_init();
7357
7358         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7359
7360         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7361                 panic("SELinux: Unable to register AVC netcache callback\n");
7362
7363         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7364                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7365
7366         if (selinux_enforcing_boot)
7367                 pr_debug("SELinux:  Starting in enforcing mode\n");
7368         else
7369                 pr_debug("SELinux:  Starting in permissive mode\n");
7370
7371         fs_validate_description("selinux", selinux_fs_parameters);
7372
7373         return 0;
7374 }
7375
7376 static void delayed_superblock_init(struct super_block *sb, void *unused)
7377 {
7378         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7379 }
7380
7381 void selinux_complete_init(void)
7382 {
7383         pr_debug("SELinux:  Completing initialization.\n");
7384
7385         /* Set up any superblocks initialized prior to the policy load. */
7386         pr_debug("SELinux:  Setting up existing superblocks.\n");
7387         iterate_supers(delayed_superblock_init, NULL);
7388 }
7389
7390 /* SELinux requires early initialization in order to label
7391    all processes and objects when they are created. */
7392 DEFINE_LSM(selinux) = {
7393         .name = "selinux",
7394         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7395         .enabled = &selinux_enabled_boot,
7396         .blobs = &selinux_blob_sizes,
7397         .init = selinux_init,
7398 };
7399
7400 #if defined(CONFIG_NETFILTER)
7401
7402 static const struct nf_hook_ops selinux_nf_ops[] = {
7403         {
7404                 .hook =         selinux_ip_postroute,
7405                 .pf =           NFPROTO_IPV4,
7406                 .hooknum =      NF_INET_POST_ROUTING,
7407                 .priority =     NF_IP_PRI_SELINUX_LAST,
7408         },
7409         {
7410                 .hook =         selinux_ip_forward,
7411                 .pf =           NFPROTO_IPV4,
7412                 .hooknum =      NF_INET_FORWARD,
7413                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7414         },
7415         {
7416                 .hook =         selinux_ip_output,
7417                 .pf =           NFPROTO_IPV4,
7418                 .hooknum =      NF_INET_LOCAL_OUT,
7419                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7420         },
7421 #if IS_ENABLED(CONFIG_IPV6)
7422         {
7423                 .hook =         selinux_ip_postroute,
7424                 .pf =           NFPROTO_IPV6,
7425                 .hooknum =      NF_INET_POST_ROUTING,
7426                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7427         },
7428         {
7429                 .hook =         selinux_ip_forward,
7430                 .pf =           NFPROTO_IPV6,
7431                 .hooknum =      NF_INET_FORWARD,
7432                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7433         },
7434         {
7435                 .hook =         selinux_ip_output,
7436                 .pf =           NFPROTO_IPV6,
7437                 .hooknum =      NF_INET_LOCAL_OUT,
7438                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7439         },
7440 #endif  /* IPV6 */
7441 };
7442
7443 static int __net_init selinux_nf_register(struct net *net)
7444 {
7445         return nf_register_net_hooks(net, selinux_nf_ops,
7446                                      ARRAY_SIZE(selinux_nf_ops));
7447 }
7448
7449 static void __net_exit selinux_nf_unregister(struct net *net)
7450 {
7451         nf_unregister_net_hooks(net, selinux_nf_ops,
7452                                 ARRAY_SIZE(selinux_nf_ops));
7453 }
7454
7455 static struct pernet_operations selinux_net_ops = {
7456         .init = selinux_nf_register,
7457         .exit = selinux_nf_unregister,
7458 };
7459
7460 static int __init selinux_nf_ip_init(void)
7461 {
7462         int err;
7463
7464         if (!selinux_enabled_boot)
7465                 return 0;
7466
7467         pr_debug("SELinux:  Registering netfilter hooks\n");
7468
7469         err = register_pernet_subsys(&selinux_net_ops);
7470         if (err)
7471                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7472
7473         return 0;
7474 }
7475 __initcall(selinux_nf_ip_init);
7476
7477 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7478 static void selinux_nf_ip_exit(void)
7479 {
7480         pr_debug("SELinux:  Unregistering netfilter hooks\n");
7481
7482         unregister_pernet_subsys(&selinux_net_ops);
7483 }
7484 #endif
7485
7486 #else /* CONFIG_NETFILTER */
7487
7488 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7489 #define selinux_nf_ip_exit()
7490 #endif
7491
7492 #endif /* CONFIG_NETFILTER */
7493
7494 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7495 int selinux_disable(struct selinux_state *state)
7496 {
7497         if (selinux_initialized(state)) {
7498                 /* Not permitted after initial policy load. */
7499                 return -EINVAL;
7500         }
7501
7502         if (selinux_disabled(state)) {
7503                 /* Only do this once. */
7504                 return -EINVAL;
7505         }
7506
7507         selinux_mark_disabled(state);
7508
7509         pr_info("SELinux:  Disabled at runtime.\n");
7510
7511         /*
7512          * Unregister netfilter hooks.
7513          * Must be done before security_delete_hooks() to avoid breaking
7514          * runtime disable.
7515          */
7516         selinux_nf_ip_exit();
7517
7518         security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7519
7520         /* Try to destroy the avc node cache */
7521         avc_disable();
7522
7523         /* Unregister selinuxfs. */
7524         exit_sel_fs();
7525
7526         return 0;
7527 }
7528 #endif