security/selinux/hooks.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Security-Enhanced Linux (SELinux) security module
   4  *
   5  *  This file contains the SELinux hook function implementations.
   6  *
   7  *  Authors:  Stephen Smalley, <stephen.smalley.work@gmail.com>
   8  *            Chris Vance, <cvance@nai.com>
   9  *            Wayne Salamon, <wsalamon@nai.com>
  10  *            James Morris <jmorris@redhat.com>
  11  *
  12  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  13  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  14  *                                         Eric Paris <eparis@redhat.com>
  15  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  16  *                          <dgoeddel@trustedcs.com>
  17  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  18  *      Paul Moore <paul@paul-moore.com>
  19  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  20  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  21  *  Copyright (C) 2016 Mellanox Technologies
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/kd.h>
  26 #include <linux/kernel.h>
  27 #include <linux/kernel_read_file.h>
  28 #include <linux/errno.h>
  29 #include <linux/sched/signal.h>
  30 #include <linux/sched/task.h>
  31 #include <linux/lsm_hooks.h>
  32 #include <linux/xattr.h>
  33 #include <linux/capability.h>
  34 #include <linux/unistd.h>
  35 #include <linux/mm.h>
  36 #include <linux/mman.h>
  37 #include <linux/slab.h>
  38 #include <linux/pagemap.h>
  39 #include <linux/proc_fs.h>
  40 #include <linux/swap.h>
  41 #include <linux/spinlock.h>
  42 #include <linux/syscalls.h>
  43 #include <linux/dcache.h>
  44 #include <linux/file.h>
  45 #include <linux/fdtable.h>
  46 #include <linux/namei.h>
  47 #include <linux/mount.h>
  48 #include <linux/fs_context.h>
  49 #include <linux/fs_parser.h>
  50 #include <linux/netfilter_ipv4.h>
  51 #include <linux/netfilter_ipv6.h>
  52 #include <linux/tty.h>
  53 #include <net/icmp.h>
  54 #include <net/ip.h>             /* for local_port_range[] */
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/inet_connection_sock.h>
  57 #include <net/net_namespace.h>
  58 #include <net/netlabel.h>
  59 #include <linux/uaccess.h>
  60 #include <asm/ioctls.h>
  61 #include <linux/atomic.h>
  62 #include <linux/bitops.h>
  63 #include <linux/interrupt.h>
  64 #include <linux/netdevice.h>    /* for network interface checks */
  65 #include <net/netlink.h>
  66 #include <linux/tcp.h>
  67 #include <linux/udp.h>
  68 #include <linux/dccp.h>
  69 #include <linux/sctp.h>
  70 #include <net/sctp/structs.h>
  71 #include <linux/quota.h>
  72 #include <linux/un.h>           /* for Unix socket types */
  73 #include <net/af_unix.h>        /* for Unix socket types */
  74 #include <linux/parser.h>
  75 #include <linux/nfs_mount.h>
  76 #include <net/ipv6.h>
  77 #include <linux/hugetlb.h>
  78 #include <linux/personality.h>
  79 #include <linux/audit.h>
  80 #include <linux/string.h>
  81 #include <linux/mutex.h>
  82 #include <linux/posix-timers.h>
  83 #include <linux/syslog.h>
  84 #include <linux/user_namespace.h>
  85 #include <linux/export.h>
  86 #include <linux/msg.h>
  87 #include <linux/shm.h>
  88 #include <uapi/linux/shm.h>
  89 #include <linux/bpf.h>
  90 #include <linux/kernfs.h>
  91 #include <linux/stringhash.h>   /* for hashlen_string() */
  92 #include <uapi/linux/mount.h>
  93 #include <linux/fsnotify.h>
  94 #include <linux/fanotify.h>
  95 #include <linux/io_uring/cmd.h>
  96 #include <uapi/linux/lsm.h>
  97
  98 #include "avc.h"
  99 #include "objsec.h"
 100 #include "netif.h"
 101 #include "netnode.h"
 102 #include "netport.h"
 103 #include "ibpkey.h"
 104 #include "xfrm.h"
 105 #include "netlabel.h"
 106 #include "audit.h"
 107 #include "avc_ss.h"
 108
 109 #define SELINUX_INODE_INIT_XATTRS 1
 110
 111 struct selinux_state selinux_state;
 112
 113 /* SECMARK reference count */
 114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 115
 116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 117 static int selinux_enforcing_boot __initdata;
 118
 119 static int __init enforcing_setup(char *str)
 120 {
 121         unsigned long enforcing;
 122         if (!kstrtoul(str, 0, &enforcing))
 123                 selinux_enforcing_boot = enforcing ? 1 : 0;
 124         return 1;
 125 }
 126 __setup("enforcing=", enforcing_setup);
 127 #else
 128 #define selinux_enforcing_boot 1
 129 #endif
 130
 131 int selinux_enabled_boot __initdata = 1;
 132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 133 static int __init selinux_enabled_setup(char *str)
 134 {
 135         unsigned long enabled;
 136         if (!kstrtoul(str, 0, &enabled))
 137                 selinux_enabled_boot = enabled ? 1 : 0;
 138         return 1;
 139 }
 140 __setup("selinux=", selinux_enabled_setup);
 141 #endif
 142
 143 static int __init checkreqprot_setup(char *str)
 144 {
 145         unsigned long checkreqprot;
 146
 147         if (!kstrtoul(str, 0, &checkreqprot)) {
 148                 if (checkreqprot)
 149                         pr_err("SELinux: checkreqprot set to 1 via kernel parameter.  This is no longer supported.\n");
 150         }
 151         return 1;
 152 }
 153 __setup("checkreqprot=", checkreqprot_setup);
 154
 155 /**
 156  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 157  *
 158  * Description:
 159  * This function checks the SECMARK reference counter to see if any SECMARK
 160  * targets are currently configured, if the reference counter is greater than
 161  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 162  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 163  * policy capability is enabled, SECMARK is always considered enabled.
 164  *
 165  */
 166 static int selinux_secmark_enabled(void)
 167 {
 168         return (selinux_policycap_alwaysnetwork() ||
 169                 atomic_read(&selinux_secmark_refcount));
 170 }
 171
 172 /**
 173  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 174  *
 175  * Description:
 176  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 177  * (1) if any are enabled or false (0) if neither are enabled.  If the
 178  * always_check_network policy capability is enabled, peer labeling
 179  * is always considered enabled.
 180  *
 181  */
 182 static int selinux_peerlbl_enabled(void)
 183 {
 184         return (selinux_policycap_alwaysnetwork() ||
 185                 netlbl_enabled() || selinux_xfrm_enabled());
 186 }
 187
 188 static int selinux_netcache_avc_callback(u32 event)
 189 {
 190         if (event == AVC_CALLBACK_RESET) {
 191                 sel_netif_flush();
 192                 sel_netnode_flush();
 193                 sel_netport_flush();
 194                 synchronize_net();
 195         }
 196         return 0;
 197 }
 198
 199 static int selinux_lsm_notifier_avc_callback(u32 event)
 200 {
 201         if (event == AVC_CALLBACK_RESET) {
 202                 sel_ib_pkey_flush();
 203                 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 204         }
 205
 206         return 0;
 207 }
 208
 209 /*
 210  * initialise the security for the init task
 211  */
 212 static void cred_init_security(void)
 213 {
 214         struct task_security_struct *tsec;
 215
 216         tsec = selinux_cred(unrcu_pointer(current->real_cred));
 217         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 218 }
 219
 220 /*
 221  * get the security ID of a set of credentials
 222  */
 223 static inline u32 cred_sid(const struct cred *cred)
 224 {
 225         const struct task_security_struct *tsec;
 226
 227         tsec = selinux_cred(cred);
 228         return tsec->sid;
 229 }
 230
 231 static void __ad_net_init(struct common_audit_data *ad,
 232                           struct lsm_network_audit *net,
 233                           int ifindex, struct sock *sk, u16 family)
 234 {
 235         ad->type = LSM_AUDIT_DATA_NET;
 236         ad->u.net = net;
 237         net->netif = ifindex;
 238         net->sk = sk;
 239         net->family = family;
 240 }
 241
 242 static void ad_net_init_from_sk(struct common_audit_data *ad,
 243                                 struct lsm_network_audit *net,
 244                                 struct sock *sk)
 245 {
 246         __ad_net_init(ad, net, 0, sk, 0);
 247 }
 248
 249 static void ad_net_init_from_iif(struct common_audit_data *ad,
 250                                  struct lsm_network_audit *net,
 251                                  int ifindex, u16 family)
 252 {
 253         __ad_net_init(ad, net, ifindex, NULL, family);
 254 }
 255
 256 /*
 257  * get the objective security ID of a task
 258  */
 259 static inline u32 task_sid_obj(const struct task_struct *task)
 260 {
 261         u32 sid;
 262
 263         rcu_read_lock();
 264         sid = cred_sid(__task_cred(task));
 265         rcu_read_unlock();
 266         return sid;
 267 }
 268
 269 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 270
 271 /*
 272  * Try reloading inode security labels that have been marked as invalid.  The
 273  * @may_sleep parameter indicates when sleeping and thus reloading labels is
 274  * allowed; when set to false, returns -ECHILD when the label is
 275  * invalid.  The @dentry parameter should be set to a dentry of the inode.
 276  */
 277 static int __inode_security_revalidate(struct inode *inode,
 278                                        struct dentry *dentry,
 279                                        bool may_sleep)
 280 {
 281         struct inode_security_struct *isec = selinux_inode(inode);
 282
 283         might_sleep_if(may_sleep);
 284
 285         if (selinux_initialized() &&
 286             isec->initialized != LABEL_INITIALIZED) {
 287                 if (!may_sleep)
 288                         return -ECHILD;
 289
 290                 /*
 291                  * Try reloading the inode security label.  This will fail if
 292                  * @opt_dentry is NULL and no dentry for this inode can be
 293                  * found; in that case, continue using the old label.
 294                  */
 295                 inode_doinit_with_dentry(inode, dentry);
 296         }
 297         return 0;
 298 }
 299
 300 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 301 {
 302         return selinux_inode(inode);
 303 }
 304
 305 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 306 {
 307         int error;
 308
 309         error = __inode_security_revalidate(inode, NULL, !rcu);
 310         if (error)
 311                 return ERR_PTR(error);
 312         return selinux_inode(inode);
 313 }
 314
 315 /*
 316  * Get the security label of an inode.
 317  */
 318 static struct inode_security_struct *inode_security(struct inode *inode)
 319 {
 320         __inode_security_revalidate(inode, NULL, true);
 321         return selinux_inode(inode);
 322 }
 323
 324 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 325 {
 326         struct inode *inode = d_backing_inode(dentry);
 327
 328         return selinux_inode(inode);
 329 }
 330
 331 /*
 332  * Get the security label of a dentry's backing inode.
 333  */
 334 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 335 {
 336         struct inode *inode = d_backing_inode(dentry);
 337
 338         __inode_security_revalidate(inode, dentry, true);
 339         return selinux_inode(inode);
 340 }
 341
 342 static void inode_free_security(struct inode *inode)
 343 {
 344         struct inode_security_struct *isec = selinux_inode(inode);
 345         struct superblock_security_struct *sbsec;
 346
 347         if (!isec)
 348                 return;
 349         sbsec = selinux_superblock(inode->i_sb);
 350         /*
 351          * As not all inode security structures are in a list, we check for
 352          * empty list outside of the lock to make sure that we won't waste
 353          * time taking a lock doing nothing.
 354          *
 355          * The list_del_init() function can be safely called more than once.
 356          * It should not be possible for this function to be called with
 357          * concurrent list_add(), but for better safety against future changes
 358          * in the code, we use list_empty_careful() here.
 359          */
 360         if (!list_empty_careful(&isec->list)) {
 361                 spin_lock(&sbsec->isec_lock);
 362                 list_del_init(&isec->list);
 363                 spin_unlock(&sbsec->isec_lock);
 364         }
 365 }
 366
 367 struct selinux_mnt_opts {
 368         u32 fscontext_sid;
 369         u32 context_sid;
 370         u32 rootcontext_sid;
 371         u32 defcontext_sid;
 372 };
 373
 374 static void selinux_free_mnt_opts(void *mnt_opts)
 375 {
 376         kfree(mnt_opts);
 377 }
 378
 379 enum {
 380         Opt_error = -1,
 381         Opt_context = 0,
 382         Opt_defcontext = 1,
 383         Opt_fscontext = 2,
 384         Opt_rootcontext = 3,
 385         Opt_seclabel = 4,
 386 };
 387
 388 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
 389 static const struct {
 390         const char *name;
 391         int len;
 392         int opt;
 393         bool has_arg;
 394 } tokens[] = {
 395         A(context, true),
 396         A(fscontext, true),
 397         A(defcontext, true),
 398         A(rootcontext, true),
 399         A(seclabel, false),
 400 };
 401 #undef A
 402
 403 static int match_opt_prefix(char *s, int l, char **arg)
 404 {
 405         int i;
 406
 407         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 408                 size_t len = tokens[i].len;
 409                 if (len > l || memcmp(s, tokens[i].name, len))
 410                         continue;
 411                 if (tokens[i].has_arg) {
 412                         if (len == l || s[len] != '=')
 413                                 continue;
 414                         *arg = s + len + 1;
 415                 } else if (len != l)
 416                         continue;
 417                 return tokens[i].opt;
 418         }
 419         return Opt_error;
 420 }
 421
 422 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 423
 424 static int may_context_mount_sb_relabel(u32 sid,
 425                         struct superblock_security_struct *sbsec,
 426                         const struct cred *cred)
 427 {
 428         const struct task_security_struct *tsec = selinux_cred(cred);
 429         int rc;
 430
 431         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 432                           FILESYSTEM__RELABELFROM, NULL);
 433         if (rc)
 434                 return rc;
 435
 436         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 437                           FILESYSTEM__RELABELTO, NULL);
 438         return rc;
 439 }
 440
 441 static int may_context_mount_inode_relabel(u32 sid,
 442                         struct superblock_security_struct *sbsec,
 443                         const struct cred *cred)
 444 {
 445         const struct task_security_struct *tsec = selinux_cred(cred);
 446         int rc;
 447         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 448                           FILESYSTEM__RELABELFROM, NULL);
 449         if (rc)
 450                 return rc;
 451
 452         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 453                           FILESYSTEM__ASSOCIATE, NULL);
 454         return rc;
 455 }
 456
 457 static int selinux_is_genfs_special_handling(struct super_block *sb)
 458 {
 459         /* Special handling. Genfs but also in-core setxattr handler */
 460         return  !strcmp(sb->s_type->name, "sysfs") ||
 461                 !strcmp(sb->s_type->name, "pstore") ||
 462                 !strcmp(sb->s_type->name, "debugfs") ||
 463                 !strcmp(sb->s_type->name, "tracefs") ||
 464                 !strcmp(sb->s_type->name, "rootfs") ||
 465                 (selinux_policycap_cgroupseclabel() &&
 466                  (!strcmp(sb->s_type->name, "cgroup") ||
 467                   !strcmp(sb->s_type->name, "cgroup2")));
 468 }
 469
 470 static int selinux_is_sblabel_mnt(struct super_block *sb)
 471 {
 472         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 473
 474         /*
 475          * IMPORTANT: Double-check logic in this function when adding a new
 476          * SECURITY_FS_USE_* definition!
 477          */
 478         BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
 479
 480         switch (sbsec->behavior) {
 481         case SECURITY_FS_USE_XATTR:
 482         case SECURITY_FS_USE_TRANS:
 483         case SECURITY_FS_USE_TASK:
 484         case SECURITY_FS_USE_NATIVE:
 485                 return 1;
 486
 487         case SECURITY_FS_USE_GENFS:
 488                 return selinux_is_genfs_special_handling(sb);
 489
 490         /* Never allow relabeling on context mounts */
 491         case SECURITY_FS_USE_MNTPOINT:
 492         case SECURITY_FS_USE_NONE:
 493         default:
 494                 return 0;
 495         }
 496 }
 497
 498 static int sb_check_xattr_support(struct super_block *sb)
 499 {
 500         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 501         struct dentry *root = sb->s_root;
 502         struct inode *root_inode = d_backing_inode(root);
 503         u32 sid;
 504         int rc;
 505
 506         /*
 507          * Make sure that the xattr handler exists and that no
 508          * error other than -ENODATA is returned by getxattr on
 509          * the root directory.  -ENODATA is ok, as this may be
 510          * the first boot of the SELinux kernel before we have
 511          * assigned xattr values to the filesystem.
 512          */
 513         if (!(root_inode->i_opflags & IOP_XATTR)) {
 514                 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
 515                         sb->s_id, sb->s_type->name);
 516                 goto fallback;
 517         }
 518
 519         rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 520         if (rc < 0 && rc != -ENODATA) {
 521                 if (rc == -EOPNOTSUPP) {
 522                         pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
 523                                 sb->s_id, sb->s_type->name);
 524                         goto fallback;
 525                 } else {
 526                         pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
 527                                 sb->s_id, sb->s_type->name, -rc);
 528                         return rc;
 529                 }
 530         }
 531         return 0;
 532
 533 fallback:
 534         /* No xattr support - try to fallback to genfs if possible. */
 535         rc = security_genfs_sid(sb->s_type->name, "/",
 536                                 SECCLASS_DIR, &sid);
 537         if (rc)
 538                 return -EOPNOTSUPP;
 539
 540         pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
 541                 sb->s_id, sb->s_type->name);
 542         sbsec->behavior = SECURITY_FS_USE_GENFS;
 543         sbsec->sid = sid;
 544         return 0;
 545 }
 546
 547 static int sb_finish_set_opts(struct super_block *sb)
 548 {
 549         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 550         struct dentry *root = sb->s_root;
 551         struct inode *root_inode = d_backing_inode(root);
 552         int rc = 0;
 553
 554         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 555                 rc = sb_check_xattr_support(sb);
 556                 if (rc)
 557                         return rc;
 558         }
 559
 560         sbsec->flags |= SE_SBINITIALIZED;
 561
 562         /*
 563          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 564          * leave the flag untouched because sb_clone_mnt_opts might be handing
 565          * us a superblock that needs the flag to be cleared.
 566          */
 567         if (selinux_is_sblabel_mnt(sb))
 568                 sbsec->flags |= SBLABEL_MNT;
 569         else
 570                 sbsec->flags &= ~SBLABEL_MNT;
 571
 572         /* Initialize the root inode. */
 573         rc = inode_doinit_with_dentry(root_inode, root);
 574
 575         /* Initialize any other inodes associated with the superblock, e.g.
 576            inodes created prior to initial policy load or inodes created
 577            during get_sb by a pseudo filesystem that directly
 578            populates itself. */
 579         spin_lock(&sbsec->isec_lock);
 580         while (!list_empty(&sbsec->isec_head)) {
 581                 struct inode_security_struct *isec =
 582                                 list_first_entry(&sbsec->isec_head,
 583                                            struct inode_security_struct, list);
 584                 struct inode *inode = isec->inode;
 585                 list_del_init(&isec->list);
 586                 spin_unlock(&sbsec->isec_lock);
 587                 inode = igrab(inode);
 588                 if (inode) {
 589                         if (!IS_PRIVATE(inode))
 590                                 inode_doinit_with_dentry(inode, NULL);
 591                         iput(inode);
 592                 }
 593                 spin_lock(&sbsec->isec_lock);
 594         }
 595         spin_unlock(&sbsec->isec_lock);
 596         return rc;
 597 }
 598
 599 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 600                       u32 old_sid, u32 new_sid)
 601 {
 602         char mnt_flags = sbsec->flags & SE_MNTMASK;
 603
 604         /* check if the old mount command had the same options */
 605         if (sbsec->flags & SE_SBINITIALIZED)
 606                 if (!(sbsec->flags & flag) ||
 607                     (old_sid != new_sid))
 608                         return 1;
 609
 610         /* check if we were passed the same options twice,
 611          * aka someone passed context=a,context=b
 612          */
 613         if (!(sbsec->flags & SE_SBINITIALIZED))
 614                 if (mnt_flags & flag)
 615                         return 1;
 616         return 0;
 617 }
 618
 619 /*
 620  * Allow filesystems with binary mount data to explicitly set mount point
 621  * labeling information.
 622  */
 623 static int selinux_set_mnt_opts(struct super_block *sb,
 624                                 void *mnt_opts,
 625                                 unsigned long kern_flags,
 626                                 unsigned long *set_kern_flags)
 627 {
 628         const struct cred *cred = current_cred();
 629         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 630         struct dentry *root = sb->s_root;
 631         struct selinux_mnt_opts *opts = mnt_opts;
 632         struct inode_security_struct *root_isec;
 633         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 634         u32 defcontext_sid = 0;
 635         int rc = 0;
 636
 637         /*
 638          * Specifying internal flags without providing a place to
 639          * place the results is not allowed
 640          */
 641         if (kern_flags && !set_kern_flags)
 642                 return -EINVAL;
 643
 644         mutex_lock(&sbsec->lock);
 645
 646         if (!selinux_initialized()) {
 647                 if (!opts) {
 648                         /* Defer initialization until selinux_complete_init,
 649                            after the initial policy is loaded and the security
 650                            server is ready to handle calls. */
 651                         if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 652                                 sbsec->flags |= SE_SBNATIVE;
 653                                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 654                         }
 655                         goto out;
 656                 }
 657                 rc = -EINVAL;
 658                 pr_warn("SELinux: Unable to set superblock options "
 659                         "before the security server is initialized\n");
 660                 goto out;
 661         }
 662
 663         /*
 664          * Binary mount data FS will come through this function twice.  Once
 665          * from an explicit call and once from the generic calls from the vfs.
 666          * Since the generic VFS calls will not contain any security mount data
 667          * we need to skip the double mount verification.
 668          *
 669          * This does open a hole in which we will not notice if the first
 670          * mount using this sb set explicit options and a second mount using
 671          * this sb does not set any security options.  (The first options
 672          * will be used for both mounts)
 673          */
 674         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 675             && !opts)
 676                 goto out;
 677
 678         root_isec = backing_inode_security_novalidate(root);
 679
 680         /*
 681          * parse the mount options, check if they are valid sids.
 682          * also check if someone is trying to mount the same sb more
 683          * than once with different security options.
 684          */
 685         if (opts) {
 686                 if (opts->fscontext_sid) {
 687                         fscontext_sid = opts->fscontext_sid;
 688                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 689                                         fscontext_sid))
 690                                 goto out_double_mount;
 691                         sbsec->flags |= FSCONTEXT_MNT;
 692                 }
 693                 if (opts->context_sid) {
 694                         context_sid = opts->context_sid;
 695                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 696                                         context_sid))
 697                                 goto out_double_mount;
 698                         sbsec->flags |= CONTEXT_MNT;
 699                 }
 700                 if (opts->rootcontext_sid) {
 701                         rootcontext_sid = opts->rootcontext_sid;
 702                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 703                                         rootcontext_sid))
 704                                 goto out_double_mount;
 705                         sbsec->flags |= ROOTCONTEXT_MNT;
 706                 }
 707                 if (opts->defcontext_sid) {
 708                         defcontext_sid = opts->defcontext_sid;
 709                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 710                                         defcontext_sid))
 711                                 goto out_double_mount;
 712                         sbsec->flags |= DEFCONTEXT_MNT;
 713                 }
 714         }
 715
 716         if (sbsec->flags & SE_SBINITIALIZED) {
 717                 /* previously mounted with options, but not on this attempt? */
 718                 if ((sbsec->flags & SE_MNTMASK) && !opts)
 719                         goto out_double_mount;
 720                 rc = 0;
 721                 goto out;
 722         }
 723
 724         if (strcmp(sb->s_type->name, "proc") == 0)
 725                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 726
 727         if (!strcmp(sb->s_type->name, "debugfs") ||
 728             !strcmp(sb->s_type->name, "tracefs") ||
 729             !strcmp(sb->s_type->name, "binder") ||
 730             !strcmp(sb->s_type->name, "bpf") ||
 731             !strcmp(sb->s_type->name, "pstore") ||
 732             !strcmp(sb->s_type->name, "securityfs"))
 733                 sbsec->flags |= SE_SBGENFS;
 734
 735         if (!strcmp(sb->s_type->name, "sysfs") ||
 736             !strcmp(sb->s_type->name, "cgroup") ||
 737             !strcmp(sb->s_type->name, "cgroup2"))
 738                 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 739
 740         if (!sbsec->behavior) {
 741                 /*
 742                  * Determine the labeling behavior to use for this
 743                  * filesystem type.
 744                  */
 745                 rc = security_fs_use(sb);
 746                 if (rc) {
 747                         pr_warn("%s: security_fs_use(%s) returned %d\n",
 748                                         __func__, sb->s_type->name, rc);
 749                         goto out;
 750                 }
 751         }
 752
 753         /*
 754          * If this is a user namespace mount and the filesystem type is not
 755          * explicitly whitelisted, then no contexts are allowed on the command
 756          * line and security labels must be ignored.
 757          */
 758         if (sb->s_user_ns != &init_user_ns &&
 759             strcmp(sb->s_type->name, "tmpfs") &&
 760             strcmp(sb->s_type->name, "ramfs") &&
 761             strcmp(sb->s_type->name, "devpts") &&
 762             strcmp(sb->s_type->name, "overlay")) {
 763                 if (context_sid || fscontext_sid || rootcontext_sid ||
 764                     defcontext_sid) {
 765                         rc = -EACCES;
 766                         goto out;
 767                 }
 768                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 769                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 770                         rc = security_transition_sid(current_sid(),
 771                                                      current_sid(),
 772                                                      SECCLASS_FILE, NULL,
 773                                                      &sbsec->mntpoint_sid);
 774                         if (rc)
 775                                 goto out;
 776                 }
 777                 goto out_set_opts;
 778         }
 779
 780         /* sets the context of the superblock for the fs being mounted. */
 781         if (fscontext_sid) {
 782                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 783                 if (rc)
 784                         goto out;
 785
 786                 sbsec->sid = fscontext_sid;
 787         }
 788
 789         /*
 790          * Switch to using mount point labeling behavior.
 791          * sets the label used on all file below the mountpoint, and will set
 792          * the superblock context if not already set.
 793          */
 794         if (sbsec->flags & SE_SBNATIVE) {
 795                 /*
 796                  * This means we are initializing a superblock that has been
 797                  * mounted before the SELinux was initialized and the
 798                  * filesystem requested native labeling. We had already
 799                  * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
 800                  * in the original mount attempt, so now we just need to set
 801                  * the SECURITY_FS_USE_NATIVE behavior.
 802                  */
 803                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 804         } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 805                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 806                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 807         }
 808
 809         if (context_sid) {
 810                 if (!fscontext_sid) {
 811                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 812                                                           cred);
 813                         if (rc)
 814                                 goto out;
 815                         sbsec->sid = context_sid;
 816                 } else {
 817                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 818                                                              cred);
 819                         if (rc)
 820                                 goto out;
 821                 }
 822                 if (!rootcontext_sid)
 823                         rootcontext_sid = context_sid;
 824
 825                 sbsec->mntpoint_sid = context_sid;
 826                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 827         }
 828
 829         if (rootcontext_sid) {
 830                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 831                                                      cred);
 832                 if (rc)
 833                         goto out;
 834
 835                 root_isec->sid = rootcontext_sid;
 836                 root_isec->initialized = LABEL_INITIALIZED;
 837         }
 838
 839         if (defcontext_sid) {
 840                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 841                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 842                         rc = -EINVAL;
 843                         pr_warn("SELinux: defcontext option is "
 844                                "invalid for this filesystem type\n");
 845                         goto out;
 846                 }
 847
 848                 if (defcontext_sid != sbsec->def_sid) {
 849                         rc = may_context_mount_inode_relabel(defcontext_sid,
 850                                                              sbsec, cred);
 851                         if (rc)
 852                                 goto out;
 853                 }
 854
 855                 sbsec->def_sid = defcontext_sid;
 856         }
 857
 858 out_set_opts:
 859         rc = sb_finish_set_opts(sb);
 860 out:
 861         mutex_unlock(&sbsec->lock);
 862         return rc;
 863 out_double_mount:
 864         rc = -EINVAL;
 865         pr_warn("SELinux: mount invalid.  Same superblock, different "
 866                "security settings for (dev %s, type %s)\n", sb->s_id,
 867                sb->s_type->name);
 868         goto out;
 869 }
 870
 871 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 872                                     const struct super_block *newsb)
 873 {
 874         struct superblock_security_struct *old = selinux_superblock(oldsb);
 875         struct superblock_security_struct *new = selinux_superblock(newsb);
 876         char oldflags = old->flags & SE_MNTMASK;
 877         char newflags = new->flags & SE_MNTMASK;
 878
 879         if (oldflags != newflags)
 880                 goto mismatch;
 881         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 882                 goto mismatch;
 883         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 884                 goto mismatch;
 885         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 886                 goto mismatch;
 887         if (oldflags & ROOTCONTEXT_MNT) {
 888                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 889                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 890                 if (oldroot->sid != newroot->sid)
 891                         goto mismatch;
 892         }
 893         return 0;
 894 mismatch:
 895         pr_warn("SELinux: mount invalid.  Same superblock, "
 896                             "different security settings for (dev %s, "
 897                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 898         return -EBUSY;
 899 }
 900
 901 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 902                                         struct super_block *newsb,
 903                                         unsigned long kern_flags,
 904                                         unsigned long *set_kern_flags)
 905 {
 906         int rc = 0;
 907         const struct superblock_security_struct *oldsbsec =
 908                                                 selinux_superblock(oldsb);
 909         struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
 910
 911         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 912         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 913         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 914
 915         /*
 916          * Specifying internal flags without providing a place to
 917          * place the results is not allowed.
 918          */
 919         if (kern_flags && !set_kern_flags)
 920                 return -EINVAL;
 921
 922         mutex_lock(&newsbsec->lock);
 923
 924         /*
 925          * if the parent was able to be mounted it clearly had no special lsm
 926          * mount options.  thus we can safely deal with this superblock later
 927          */
 928         if (!selinux_initialized()) {
 929                 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 930                         newsbsec->flags |= SE_SBNATIVE;
 931                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 932                 }
 933                 goto out;
 934         }
 935
 936         /* how can we clone if the old one wasn't set up?? */
 937         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 938
 939         /* if fs is reusing a sb, make sure that the contexts match */
 940         if (newsbsec->flags & SE_SBINITIALIZED) {
 941                 mutex_unlock(&newsbsec->lock);
 942                 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
 943                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 944                 return selinux_cmp_sb_context(oldsb, newsb);
 945         }
 946
 947         newsbsec->flags = oldsbsec->flags;
 948
 949         newsbsec->sid = oldsbsec->sid;
 950         newsbsec->def_sid = oldsbsec->def_sid;
 951         newsbsec->behavior = oldsbsec->behavior;
 952
 953         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
 954                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
 955                 rc = security_fs_use(newsb);
 956                 if (rc)
 957                         goto out;
 958         }
 959
 960         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
 961                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
 962                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 963         }
 964
 965         if (set_context) {
 966                 u32 sid = oldsbsec->mntpoint_sid;
 967
 968                 if (!set_fscontext)
 969                         newsbsec->sid = sid;
 970                 if (!set_rootcontext) {
 971                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 972                         newisec->sid = sid;
 973                 }
 974                 newsbsec->mntpoint_sid = sid;
 975         }
 976         if (set_rootcontext) {
 977                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
 978                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 979
 980                 newisec->sid = oldisec->sid;
 981         }
 982
 983         sb_finish_set_opts(newsb);
 984 out:
 985         mutex_unlock(&newsbsec->lock);
 986         return rc;
 987 }
 988
 989 /*
 990  * NOTE: the caller is responsible for freeing the memory even if on error.
 991  */
 992 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 993 {
 994         struct selinux_mnt_opts *opts = *mnt_opts;
 995         u32 *dst_sid;
 996         int rc;
 997
 998         if (token == Opt_seclabel)
 999                 /* eaten and completely ignored */
1000                 return 0;
1001         if (!s)
1002                 return -EINVAL;
1003
1004         if (!selinux_initialized()) {
1005                 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1006                 return -EINVAL;
1007         }
1008
1009         if (!opts) {
1010                 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1011                 if (!opts)
1012                         return -ENOMEM;
1013                 *mnt_opts = opts;
1014         }
1015
1016         switch (token) {
1017         case Opt_context:
1018                 if (opts->context_sid || opts->defcontext_sid)
1019                         goto err;
1020                 dst_sid = &opts->context_sid;
1021                 break;
1022         case Opt_fscontext:
1023                 if (opts->fscontext_sid)
1024                         goto err;
1025                 dst_sid = &opts->fscontext_sid;
1026                 break;
1027         case Opt_rootcontext:
1028                 if (opts->rootcontext_sid)
1029                         goto err;
1030                 dst_sid = &opts->rootcontext_sid;
1031                 break;
1032         case Opt_defcontext:
1033                 if (opts->context_sid || opts->defcontext_sid)
1034                         goto err;
1035                 dst_sid = &opts->defcontext_sid;
1036                 break;
1037         default:
1038                 WARN_ON(1);
1039                 return -EINVAL;
1040         }
1041         rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1042         if (rc)
1043                 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1044                         s, rc);
1045         return rc;
1046
1047 err:
1048         pr_warn(SEL_MOUNT_FAIL_MSG);
1049         return -EINVAL;
1050 }
1051
1052 static int show_sid(struct seq_file *m, u32 sid)
1053 {
1054         char *context = NULL;
1055         u32 len;
1056         int rc;
1057
1058         rc = security_sid_to_context(sid, &context, &len);
1059         if (!rc) {
1060                 bool has_comma = strchr(context, ',');
1061
1062                 seq_putc(m, '=');
1063                 if (has_comma)
1064                         seq_putc(m, '\"');
1065                 seq_escape(m, context, "\"\n\\");
1066                 if (has_comma)
1067                         seq_putc(m, '\"');
1068         }
1069         kfree(context);
1070         return rc;
1071 }
1072
1073 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1074 {
1075         struct superblock_security_struct *sbsec = selinux_superblock(sb);
1076         int rc;
1077
1078         if (!(sbsec->flags & SE_SBINITIALIZED))
1079                 return 0;
1080
1081         if (!selinux_initialized())
1082                 return 0;
1083
1084         if (sbsec->flags & FSCONTEXT_MNT) {
1085                 seq_putc(m, ',');
1086                 seq_puts(m, FSCONTEXT_STR);
1087                 rc = show_sid(m, sbsec->sid);
1088                 if (rc)
1089                         return rc;
1090         }
1091         if (sbsec->flags & CONTEXT_MNT) {
1092                 seq_putc(m, ',');
1093                 seq_puts(m, CONTEXT_STR);
1094                 rc = show_sid(m, sbsec->mntpoint_sid);
1095                 if (rc)
1096                         return rc;
1097         }
1098         if (sbsec->flags & DEFCONTEXT_MNT) {
1099                 seq_putc(m, ',');
1100                 seq_puts(m, DEFCONTEXT_STR);
1101                 rc = show_sid(m, sbsec->def_sid);
1102                 if (rc)
1103                         return rc;
1104         }
1105         if (sbsec->flags & ROOTCONTEXT_MNT) {
1106                 struct dentry *root = sb->s_root;
1107                 struct inode_security_struct *isec = backing_inode_security(root);
1108                 seq_putc(m, ',');
1109                 seq_puts(m, ROOTCONTEXT_STR);
1110                 rc = show_sid(m, isec->sid);
1111                 if (rc)
1112                         return rc;
1113         }
1114         if (sbsec->flags & SBLABEL_MNT) {
1115                 seq_putc(m, ',');
1116                 seq_puts(m, SECLABEL_STR);
1117         }
1118         return 0;
1119 }
1120
1121 static inline u16 inode_mode_to_security_class(umode_t mode)
1122 {
1123         switch (mode & S_IFMT) {
1124         case S_IFSOCK:
1125                 return SECCLASS_SOCK_FILE;
1126         case S_IFLNK:
1127                 return SECCLASS_LNK_FILE;
1128         case S_IFREG:
1129                 return SECCLASS_FILE;
1130         case S_IFBLK:
1131                 return SECCLASS_BLK_FILE;
1132         case S_IFDIR:
1133                 return SECCLASS_DIR;
1134         case S_IFCHR:
1135                 return SECCLASS_CHR_FILE;
1136         case S_IFIFO:
1137                 return SECCLASS_FIFO_FILE;
1138
1139         }
1140
1141         return SECCLASS_FILE;
1142 }
1143
1144 static inline int default_protocol_stream(int protocol)
1145 {
1146         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1147                 protocol == IPPROTO_MPTCP);
1148 }
1149
1150 static inline int default_protocol_dgram(int protocol)
1151 {
1152         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1153 }
1154
1155 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1156 {
1157         bool extsockclass = selinux_policycap_extsockclass();
1158
1159         switch (family) {
1160         case PF_UNIX:
1161                 switch (type) {
1162                 case SOCK_STREAM:
1163                 case SOCK_SEQPACKET:
1164                         return SECCLASS_UNIX_STREAM_SOCKET;
1165                 case SOCK_DGRAM:
1166                 case SOCK_RAW:
1167                         return SECCLASS_UNIX_DGRAM_SOCKET;
1168                 }
1169                 break;
1170         case PF_INET:
1171         case PF_INET6:
1172                 switch (type) {
1173                 case SOCK_STREAM:
1174                 case SOCK_SEQPACKET:
1175                         if (default_protocol_stream(protocol))
1176                                 return SECCLASS_TCP_SOCKET;
1177                         else if (extsockclass && protocol == IPPROTO_SCTP)
1178                                 return SECCLASS_SCTP_SOCKET;
1179                         else
1180                                 return SECCLASS_RAWIP_SOCKET;
1181                 case SOCK_DGRAM:
1182                         if (default_protocol_dgram(protocol))
1183                                 return SECCLASS_UDP_SOCKET;
1184                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1185                                                   protocol == IPPROTO_ICMPV6))
1186                                 return SECCLASS_ICMP_SOCKET;
1187                         else
1188                                 return SECCLASS_RAWIP_SOCKET;
1189                 case SOCK_DCCP:
1190                         return SECCLASS_DCCP_SOCKET;
1191                 default:
1192                         return SECCLASS_RAWIP_SOCKET;
1193                 }
1194                 break;
1195         case PF_NETLINK:
1196                 switch (protocol) {
1197                 case NETLINK_ROUTE:
1198                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1199                 case NETLINK_SOCK_DIAG:
1200                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1201                 case NETLINK_NFLOG:
1202                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1203                 case NETLINK_XFRM:
1204                         return SECCLASS_NETLINK_XFRM_SOCKET;
1205                 case NETLINK_SELINUX:
1206                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1207                 case NETLINK_ISCSI:
1208                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1209                 case NETLINK_AUDIT:
1210                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1211                 case NETLINK_FIB_LOOKUP:
1212                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1213                 case NETLINK_CONNECTOR:
1214                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1215                 case NETLINK_NETFILTER:
1216                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1217                 case NETLINK_DNRTMSG:
1218                         return SECCLASS_NETLINK_DNRT_SOCKET;
1219                 case NETLINK_KOBJECT_UEVENT:
1220                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1221                 case NETLINK_GENERIC:
1222                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1223                 case NETLINK_SCSITRANSPORT:
1224                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1225                 case NETLINK_RDMA:
1226                         return SECCLASS_NETLINK_RDMA_SOCKET;
1227                 case NETLINK_CRYPTO:
1228                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1229                 default:
1230                         return SECCLASS_NETLINK_SOCKET;
1231                 }
1232         case PF_PACKET:
1233                 return SECCLASS_PACKET_SOCKET;
1234         case PF_KEY:
1235                 return SECCLASS_KEY_SOCKET;
1236         case PF_APPLETALK:
1237                 return SECCLASS_APPLETALK_SOCKET;
1238         }
1239
1240         if (extsockclass) {
1241                 switch (family) {
1242                 case PF_AX25:
1243                         return SECCLASS_AX25_SOCKET;
1244                 case PF_IPX:
1245                         return SECCLASS_IPX_SOCKET;
1246                 case PF_NETROM:
1247                         return SECCLASS_NETROM_SOCKET;
1248                 case PF_ATMPVC:
1249                         return SECCLASS_ATMPVC_SOCKET;
1250                 case PF_X25:
1251                         return SECCLASS_X25_SOCKET;
1252                 case PF_ROSE:
1253                         return SECCLASS_ROSE_SOCKET;
1254                 case PF_DECnet:
1255                         return SECCLASS_DECNET_SOCKET;
1256                 case PF_ATMSVC:
1257                         return SECCLASS_ATMSVC_SOCKET;
1258                 case PF_RDS:
1259                         return SECCLASS_RDS_SOCKET;
1260                 case PF_IRDA:
1261                         return SECCLASS_IRDA_SOCKET;
1262                 case PF_PPPOX:
1263                         return SECCLASS_PPPOX_SOCKET;
1264                 case PF_LLC:
1265                         return SECCLASS_LLC_SOCKET;
1266                 case PF_CAN:
1267                         return SECCLASS_CAN_SOCKET;
1268                 case PF_TIPC:
1269                         return SECCLASS_TIPC_SOCKET;
1270                 case PF_BLUETOOTH:
1271                         return SECCLASS_BLUETOOTH_SOCKET;
1272                 case PF_IUCV:
1273                         return SECCLASS_IUCV_SOCKET;
1274                 case PF_RXRPC:
1275                         return SECCLASS_RXRPC_SOCKET;
1276                 case PF_ISDN:
1277                         return SECCLASS_ISDN_SOCKET;
1278                 case PF_PHONET:
1279                         return SECCLASS_PHONET_SOCKET;
1280                 case PF_IEEE802154:
1281                         return SECCLASS_IEEE802154_SOCKET;
1282                 case PF_CAIF:
1283                         return SECCLASS_CAIF_SOCKET;
1284                 case PF_ALG:
1285                         return SECCLASS_ALG_SOCKET;
1286                 case PF_NFC:
1287                         return SECCLASS_NFC_SOCKET;
1288                 case PF_VSOCK:
1289                         return SECCLASS_VSOCK_SOCKET;
1290                 case PF_KCM:
1291                         return SECCLASS_KCM_SOCKET;
1292                 case PF_QIPCRTR:
1293                         return SECCLASS_QIPCRTR_SOCKET;
1294                 case PF_SMC:
1295                         return SECCLASS_SMC_SOCKET;
1296                 case PF_XDP:
1297                         return SECCLASS_XDP_SOCKET;
1298                 case PF_MCTP:
1299                         return SECCLASS_MCTP_SOCKET;
1300 #if PF_MAX > 46
1301 #error New address family defined, please update this function.
1302 #endif
1303                 }
1304         }
1305
1306         return SECCLASS_SOCKET;
1307 }
1308
1309 static int selinux_genfs_get_sid(struct dentry *dentry,
1310                                  u16 tclass,
1311                                  u16 flags,
1312                                  u32 *sid)
1313 {
1314         int rc;
1315         struct super_block *sb = dentry->d_sb;
1316         char *buffer, *path;
1317
1318         buffer = (char *)__get_free_page(GFP_KERNEL);
1319         if (!buffer)
1320                 return -ENOMEM;
1321
1322         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1323         if (IS_ERR(path))
1324                 rc = PTR_ERR(path);
1325         else {
1326                 if (flags & SE_SBPROC) {
1327                         /* each process gets a /proc/PID/ entry. Strip off the
1328                          * PID part to get a valid selinux labeling.
1329                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1330                         while (path[1] >= '0' && path[1] <= '9') {
1331                                 path[1] = '/';
1332                                 path++;
1333                         }
1334                 }
1335                 rc = security_genfs_sid(sb->s_type->name,
1336                                         path, tclass, sid);
1337                 if (rc == -ENOENT) {
1338                         /* No match in policy, mark as unlabeled. */
1339                         *sid = SECINITSID_UNLABELED;
1340                         rc = 0;
1341                 }
1342         }
1343         free_page((unsigned long)buffer);
1344         return rc;
1345 }
1346
1347 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1348                                   u32 def_sid, u32 *sid)
1349 {
1350 #define INITCONTEXTLEN 255
1351         char *context;
1352         unsigned int len;
1353         int rc;
1354
1355         len = INITCONTEXTLEN;
1356         context = kmalloc(len + 1, GFP_NOFS);
1357         if (!context)
1358                 return -ENOMEM;
1359
1360         context[len] = '\0';
1361         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1362         if (rc == -ERANGE) {
1363                 kfree(context);
1364
1365                 /* Need a larger buffer.  Query for the right size. */
1366                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1367                 if (rc < 0)
1368                         return rc;
1369
1370                 len = rc;
1371                 context = kmalloc(len + 1, GFP_NOFS);
1372                 if (!context)
1373                         return -ENOMEM;
1374
1375                 context[len] = '\0';
1376                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1377                                     context, len);
1378         }
1379         if (rc < 0) {
1380                 kfree(context);
1381                 if (rc != -ENODATA) {
1382                         pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1383                                 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1384                         return rc;
1385                 }
1386                 *sid = def_sid;
1387                 return 0;
1388         }
1389
1390         rc = security_context_to_sid_default(context, rc, sid,
1391                                              def_sid, GFP_NOFS);
1392         if (rc) {
1393                 char *dev = inode->i_sb->s_id;
1394                 unsigned long ino = inode->i_ino;
1395
1396                 if (rc == -EINVAL) {
1397                         pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1398                                               ino, dev, context);
1399                 } else {
1400                         pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1401                                 __func__, context, -rc, dev, ino);
1402                 }
1403         }
1404         kfree(context);
1405         return 0;
1406 }
1407
1408 /* The inode's security attributes must be initialized before first use. */
1409 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1410 {
1411         struct superblock_security_struct *sbsec = NULL;
1412         struct inode_security_struct *isec = selinux_inode(inode);
1413         u32 task_sid, sid = 0;
1414         u16 sclass;
1415         struct dentry *dentry;
1416         int rc = 0;
1417
1418         if (isec->initialized == LABEL_INITIALIZED)
1419                 return 0;
1420
1421         spin_lock(&isec->lock);
1422         if (isec->initialized == LABEL_INITIALIZED)
1423                 goto out_unlock;
1424
1425         if (isec->sclass == SECCLASS_FILE)
1426                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1427
1428         sbsec = selinux_superblock(inode->i_sb);
1429         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1430                 /* Defer initialization until selinux_complete_init,
1431                    after the initial policy is loaded and the security
1432                    server is ready to handle calls. */
1433                 spin_lock(&sbsec->isec_lock);
1434                 if (list_empty(&isec->list))
1435                         list_add(&isec->list, &sbsec->isec_head);
1436                 spin_unlock(&sbsec->isec_lock);
1437                 goto out_unlock;
1438         }
1439
1440         sclass = isec->sclass;
1441         task_sid = isec->task_sid;
1442         sid = isec->sid;
1443         isec->initialized = LABEL_PENDING;
1444         spin_unlock(&isec->lock);
1445
1446         switch (sbsec->behavior) {
1447         /*
1448          * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1449          * via xattr when called from delayed_superblock_init().
1450          */
1451         case SECURITY_FS_USE_NATIVE:
1452         case SECURITY_FS_USE_XATTR:
1453                 if (!(inode->i_opflags & IOP_XATTR)) {
1454                         sid = sbsec->def_sid;
1455                         break;
1456                 }
1457                 /* Need a dentry, since the xattr API requires one.
1458                    Life would be simpler if we could just pass the inode. */
1459                 if (opt_dentry) {
1460                         /* Called from d_instantiate or d_splice_alias. */
1461                         dentry = dget(opt_dentry);
1462                 } else {
1463                         /*
1464                          * Called from selinux_complete_init, try to find a dentry.
1465                          * Some filesystems really want a connected one, so try
1466                          * that first.  We could split SECURITY_FS_USE_XATTR in
1467                          * two, depending upon that...
1468                          */
1469                         dentry = d_find_alias(inode);
1470                         if (!dentry)
1471                                 dentry = d_find_any_alias(inode);
1472                 }
1473                 if (!dentry) {
1474                         /*
1475                          * this is can be hit on boot when a file is accessed
1476                          * before the policy is loaded.  When we load policy we
1477                          * may find inodes that have no dentry on the
1478                          * sbsec->isec_head list.  No reason to complain as these
1479                          * will get fixed up the next time we go through
1480                          * inode_doinit with a dentry, before these inodes could
1481                          * be used again by userspace.
1482                          */
1483                         goto out_invalid;
1484                 }
1485
1486                 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1487                                             &sid);
1488                 dput(dentry);
1489                 if (rc)
1490                         goto out;
1491                 break;
1492         case SECURITY_FS_USE_TASK:
1493                 sid = task_sid;
1494                 break;
1495         case SECURITY_FS_USE_TRANS:
1496                 /* Default to the fs SID. */
1497                 sid = sbsec->sid;
1498
1499                 /* Try to obtain a transition SID. */
1500                 rc = security_transition_sid(task_sid, sid,
1501                                              sclass, NULL, &sid);
1502                 if (rc)
1503                         goto out;
1504                 break;
1505         case SECURITY_FS_USE_MNTPOINT:
1506                 sid = sbsec->mntpoint_sid;
1507                 break;
1508         default:
1509                 /* Default to the fs superblock SID. */
1510                 sid = sbsec->sid;
1511
1512                 if ((sbsec->flags & SE_SBGENFS) &&
1513                      (!S_ISLNK(inode->i_mode) ||
1514                       selinux_policycap_genfs_seclabel_symlinks())) {
1515                         /* We must have a dentry to determine the label on
1516                          * procfs inodes */
1517                         if (opt_dentry) {
1518                                 /* Called from d_instantiate or
1519                                  * d_splice_alias. */
1520                                 dentry = dget(opt_dentry);
1521                         } else {
1522                                 /* Called from selinux_complete_init, try to
1523                                  * find a dentry.  Some filesystems really want
1524                                  * a connected one, so try that first.
1525                                  */
1526                                 dentry = d_find_alias(inode);
1527                                 if (!dentry)
1528                                         dentry = d_find_any_alias(inode);
1529                         }
1530                         /*
1531                          * This can be hit on boot when a file is accessed
1532                          * before the policy is loaded.  When we load policy we
1533                          * may find inodes that have no dentry on the
1534                          * sbsec->isec_head list.  No reason to complain as
1535                          * these will get fixed up the next time we go through
1536                          * inode_doinit() with a dentry, before these inodes
1537                          * could be used again by userspace.
1538                          */
1539                         if (!dentry)
1540                                 goto out_invalid;
1541                         rc = selinux_genfs_get_sid(dentry, sclass,
1542                                                    sbsec->flags, &sid);
1543                         if (rc) {
1544                                 dput(dentry);
1545                                 goto out;
1546                         }
1547
1548                         if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1549                             (inode->i_opflags & IOP_XATTR)) {
1550                                 rc = inode_doinit_use_xattr(inode, dentry,
1551                                                             sid, &sid);
1552                                 if (rc) {
1553                                         dput(dentry);
1554                                         goto out;
1555                                 }
1556                         }
1557                         dput(dentry);
1558                 }
1559                 break;
1560         }
1561
1562 out:
1563         spin_lock(&isec->lock);
1564         if (isec->initialized == LABEL_PENDING) {
1565                 if (rc) {
1566                         isec->initialized = LABEL_INVALID;
1567                         goto out_unlock;
1568                 }
1569                 isec->initialized = LABEL_INITIALIZED;
1570                 isec->sid = sid;
1571         }
1572
1573 out_unlock:
1574         spin_unlock(&isec->lock);
1575         return rc;
1576
1577 out_invalid:
1578         spin_lock(&isec->lock);
1579         if (isec->initialized == LABEL_PENDING) {
1580                 isec->initialized = LABEL_INVALID;
1581                 isec->sid = sid;
1582         }
1583         spin_unlock(&isec->lock);
1584         return 0;
1585 }
1586
1587 /* Convert a Linux signal to an access vector. */
1588 static inline u32 signal_to_av(int sig)
1589 {
1590         u32 perm = 0;
1591
1592         switch (sig) {
1593         case SIGCHLD:
1594                 /* Commonly granted from child to parent. */
1595                 perm = PROCESS__SIGCHLD;
1596                 break;
1597         case SIGKILL:
1598                 /* Cannot be caught or ignored */
1599                 perm = PROCESS__SIGKILL;
1600                 break;
1601         case SIGSTOP:
1602                 /* Cannot be caught or ignored */
1603                 perm = PROCESS__SIGSTOP;
1604                 break;
1605         default:
1606                 /* All other signals. */
1607                 perm = PROCESS__SIGNAL;
1608                 break;
1609         }
1610
1611         return perm;
1612 }
1613
1614 #if CAP_LAST_CAP > 63
1615 #error Fix SELinux to handle capabilities > 63.
1616 #endif
1617
1618 /* Check whether a task is allowed to use a capability. */
1619 static int cred_has_capability(const struct cred *cred,
1620                                int cap, unsigned int opts, bool initns)
1621 {
1622         struct common_audit_data ad;
1623         struct av_decision avd;
1624         u16 sclass;
1625         u32 sid = cred_sid(cred);
1626         u32 av = CAP_TO_MASK(cap);
1627         int rc;
1628
1629         ad.type = LSM_AUDIT_DATA_CAP;
1630         ad.u.cap = cap;
1631
1632         switch (CAP_TO_INDEX(cap)) {
1633         case 0:
1634                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1635                 break;
1636         case 1:
1637                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1638                 break;
1639         default:
1640                 pr_err("SELinux:  out of range capability %d\n", cap);
1641                 BUG();
1642                 return -EINVAL;
1643         }
1644
1645         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1646         if (!(opts & CAP_OPT_NOAUDIT)) {
1647                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1648                 if (rc2)
1649                         return rc2;
1650         }
1651         return rc;
1652 }
1653
1654 /* Check whether a task has a particular permission to an inode.
1655    The 'adp' parameter is optional and allows other audit
1656    data to be passed (e.g. the dentry). */
1657 static int inode_has_perm(const struct cred *cred,
1658                           struct inode *inode,
1659                           u32 perms,
1660                           struct common_audit_data *adp)
1661 {
1662         struct inode_security_struct *isec;
1663         u32 sid;
1664
1665         if (unlikely(IS_PRIVATE(inode)))
1666                 return 0;
1667
1668         sid = cred_sid(cred);
1669         isec = selinux_inode(inode);
1670
1671         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1672 }
1673
1674 /* Same as inode_has_perm, but pass explicit audit data containing
1675    the dentry to help the auditing code to more easily generate the
1676    pathname if needed. */
1677 static inline int dentry_has_perm(const struct cred *cred,
1678                                   struct dentry *dentry,
1679                                   u32 av)
1680 {
1681         struct inode *inode = d_backing_inode(dentry);
1682         struct common_audit_data ad;
1683
1684         ad.type = LSM_AUDIT_DATA_DENTRY;
1685         ad.u.dentry = dentry;
1686         __inode_security_revalidate(inode, dentry, true);
1687         return inode_has_perm(cred, inode, av, &ad);
1688 }
1689
1690 /* Same as inode_has_perm, but pass explicit audit data containing
1691    the path to help the auditing code to more easily generate the
1692    pathname if needed. */
1693 static inline int path_has_perm(const struct cred *cred,
1694                                 const struct path *path,
1695                                 u32 av)
1696 {
1697         struct inode *inode = d_backing_inode(path->dentry);
1698         struct common_audit_data ad;
1699
1700         ad.type = LSM_AUDIT_DATA_PATH;
1701         ad.u.path = *path;
1702         __inode_security_revalidate(inode, path->dentry, true);
1703         return inode_has_perm(cred, inode, av, &ad);
1704 }
1705
1706 /* Same as path_has_perm, but uses the inode from the file struct. */
1707 static inline int file_path_has_perm(const struct cred *cred,
1708                                      struct file *file,
1709                                      u32 av)
1710 {
1711         struct common_audit_data ad;
1712
1713         ad.type = LSM_AUDIT_DATA_FILE;
1714         ad.u.file = file;
1715         return inode_has_perm(cred, file_inode(file), av, &ad);
1716 }
1717
1718 #ifdef CONFIG_BPF_SYSCALL
1719 static int bpf_fd_pass(const struct file *file, u32 sid);
1720 #endif
1721
1722 /* Check whether a task can use an open file descriptor to
1723    access an inode in a given way.  Check access to the
1724    descriptor itself, and then use dentry_has_perm to
1725    check a particular permission to the file.
1726    Access to the descriptor is implicitly granted if it
1727    has the same SID as the process.  If av is zero, then
1728    access to the file is not checked, e.g. for cases
1729    where only the descriptor is affected like seek. */
1730 static int file_has_perm(const struct cred *cred,
1731                          struct file *file,
1732                          u32 av)
1733 {
1734         struct file_security_struct *fsec = selinux_file(file);
1735         struct inode *inode = file_inode(file);
1736         struct common_audit_data ad;
1737         u32 sid = cred_sid(cred);
1738         int rc;
1739
1740         ad.type = LSM_AUDIT_DATA_FILE;
1741         ad.u.file = file;
1742
1743         if (sid != fsec->sid) {
1744                 rc = avc_has_perm(sid, fsec->sid,
1745                                   SECCLASS_FD,
1746                                   FD__USE,
1747                                   &ad);
1748                 if (rc)
1749                         goto out;
1750         }
1751
1752 #ifdef CONFIG_BPF_SYSCALL
1753         rc = bpf_fd_pass(file, cred_sid(cred));
1754         if (rc)
1755                 return rc;
1756 #endif
1757
1758         /* av is zero if only checking access to the descriptor. */
1759         rc = 0;
1760         if (av)
1761                 rc = inode_has_perm(cred, inode, av, &ad);
1762
1763 out:
1764         return rc;
1765 }
1766
1767 /*
1768  * Determine the label for an inode that might be unioned.
1769  */
1770 static int
1771 selinux_determine_inode_label(const struct task_security_struct *tsec,
1772                                  struct inode *dir,
1773                                  const struct qstr *name, u16 tclass,
1774                                  u32 *_new_isid)
1775 {
1776         const struct superblock_security_struct *sbsec =
1777                                                 selinux_superblock(dir->i_sb);
1778
1779         if ((sbsec->flags & SE_SBINITIALIZED) &&
1780             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1781                 *_new_isid = sbsec->mntpoint_sid;
1782         } else if ((sbsec->flags & SBLABEL_MNT) &&
1783                    tsec->create_sid) {
1784                 *_new_isid = tsec->create_sid;
1785         } else {
1786                 const struct inode_security_struct *dsec = inode_security(dir);
1787                 return security_transition_sid(tsec->sid,
1788                                                dsec->sid, tclass,
1789                                                name, _new_isid);
1790         }
1791
1792         return 0;
1793 }
1794
1795 /* Check whether a task can create a file. */
1796 static int may_create(struct inode *dir,
1797                       struct dentry *dentry,
1798                       u16 tclass)
1799 {
1800         const struct task_security_struct *tsec = selinux_cred(current_cred());
1801         struct inode_security_struct *dsec;
1802         struct superblock_security_struct *sbsec;
1803         u32 sid, newsid;
1804         struct common_audit_data ad;
1805         int rc;
1806
1807         dsec = inode_security(dir);
1808         sbsec = selinux_superblock(dir->i_sb);
1809
1810         sid = tsec->sid;
1811
1812         ad.type = LSM_AUDIT_DATA_DENTRY;
1813         ad.u.dentry = dentry;
1814
1815         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1816                           DIR__ADD_NAME | DIR__SEARCH,
1817                           &ad);
1818         if (rc)
1819                 return rc;
1820
1821         rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1822                                            &newsid);
1823         if (rc)
1824                 return rc;
1825
1826         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1827         if (rc)
1828                 return rc;
1829
1830         return avc_has_perm(newsid, sbsec->sid,
1831                             SECCLASS_FILESYSTEM,
1832                             FILESYSTEM__ASSOCIATE, &ad);
1833 }
1834
1835 #define MAY_LINK        0
1836 #define MAY_UNLINK      1
1837 #define MAY_RMDIR       2
1838
1839 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1840 static int may_link(struct inode *dir,
1841                     struct dentry *dentry,
1842                     int kind)
1843
1844 {
1845         struct inode_security_struct *dsec, *isec;
1846         struct common_audit_data ad;
1847         u32 sid = current_sid();
1848         u32 av;
1849         int rc;
1850
1851         dsec = inode_security(dir);
1852         isec = backing_inode_security(dentry);
1853
1854         ad.type = LSM_AUDIT_DATA_DENTRY;
1855         ad.u.dentry = dentry;
1856
1857         av = DIR__SEARCH;
1858         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1859         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1860         if (rc)
1861                 return rc;
1862
1863         switch (kind) {
1864         case MAY_LINK:
1865                 av = FILE__LINK;
1866                 break;
1867         case MAY_UNLINK:
1868                 av = FILE__UNLINK;
1869                 break;
1870         case MAY_RMDIR:
1871                 av = DIR__RMDIR;
1872                 break;
1873         default:
1874                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
1875                         __func__, kind);
1876                 return 0;
1877         }
1878
1879         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1880         return rc;
1881 }
1882
1883 static inline int may_rename(struct inode *old_dir,
1884                              struct dentry *old_dentry,
1885                              struct inode *new_dir,
1886                              struct dentry *new_dentry)
1887 {
1888         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1889         struct common_audit_data ad;
1890         u32 sid = current_sid();
1891         u32 av;
1892         int old_is_dir, new_is_dir;
1893         int rc;
1894
1895         old_dsec = inode_security(old_dir);
1896         old_isec = backing_inode_security(old_dentry);
1897         old_is_dir = d_is_dir(old_dentry);
1898         new_dsec = inode_security(new_dir);
1899
1900         ad.type = LSM_AUDIT_DATA_DENTRY;
1901
1902         ad.u.dentry = old_dentry;
1903         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1904                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1905         if (rc)
1906                 return rc;
1907         rc = avc_has_perm(sid, old_isec->sid,
1908                           old_isec->sclass, FILE__RENAME, &ad);
1909         if (rc)
1910                 return rc;
1911         if (old_is_dir && new_dir != old_dir) {
1912                 rc = avc_has_perm(sid, old_isec->sid,
1913                                   old_isec->sclass, DIR__REPARENT, &ad);
1914                 if (rc)
1915                         return rc;
1916         }
1917
1918         ad.u.dentry = new_dentry;
1919         av = DIR__ADD_NAME | DIR__SEARCH;
1920         if (d_is_positive(new_dentry))
1921                 av |= DIR__REMOVE_NAME;
1922         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1923         if (rc)
1924                 return rc;
1925         if (d_is_positive(new_dentry)) {
1926                 new_isec = backing_inode_security(new_dentry);
1927                 new_is_dir = d_is_dir(new_dentry);
1928                 rc = avc_has_perm(sid, new_isec->sid,
1929                                   new_isec->sclass,
1930                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1931                 if (rc)
1932                         return rc;
1933         }
1934
1935         return 0;
1936 }
1937
1938 /* Check whether a task can perform a filesystem operation. */
1939 static int superblock_has_perm(const struct cred *cred,
1940                                const struct super_block *sb,
1941                                u32 perms,
1942                                struct common_audit_data *ad)
1943 {
1944         struct superblock_security_struct *sbsec;
1945         u32 sid = cred_sid(cred);
1946
1947         sbsec = selinux_superblock(sb);
1948         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1949 }
1950
1951 /* Convert a Linux mode and permission mask to an access vector. */
1952 static inline u32 file_mask_to_av(int mode, int mask)
1953 {
1954         u32 av = 0;
1955
1956         if (!S_ISDIR(mode)) {
1957                 if (mask & MAY_EXEC)
1958                         av |= FILE__EXECUTE;
1959                 if (mask & MAY_READ)
1960                         av |= FILE__READ;
1961
1962                 if (mask & MAY_APPEND)
1963                         av |= FILE__APPEND;
1964                 else if (mask & MAY_WRITE)
1965                         av |= FILE__WRITE;
1966
1967         } else {
1968                 if (mask & MAY_EXEC)
1969                         av |= DIR__SEARCH;
1970                 if (mask & MAY_WRITE)
1971                         av |= DIR__WRITE;
1972                 if (mask & MAY_READ)
1973                         av |= DIR__READ;
1974         }
1975
1976         return av;
1977 }
1978
1979 /* Convert a Linux file to an access vector. */
1980 static inline u32 file_to_av(const struct file *file)
1981 {
1982         u32 av = 0;
1983
1984         if (file->f_mode & FMODE_READ)
1985                 av |= FILE__READ;
1986         if (file->f_mode & FMODE_WRITE) {
1987                 if (file->f_flags & O_APPEND)
1988                         av |= FILE__APPEND;
1989                 else
1990                         av |= FILE__WRITE;
1991         }
1992         if (!av) {
1993                 /*
1994                  * Special file opened with flags 3 for ioctl-only use.
1995                  */
1996                 av = FILE__IOCTL;
1997         }
1998
1999         return av;
2000 }
2001
2002 /*
2003  * Convert a file to an access vector and include the correct
2004  * open permission.
2005  */
2006 static inline u32 open_file_to_av(struct file *file)
2007 {
2008         u32 av = file_to_av(file);
2009         struct inode *inode = file_inode(file);
2010
2011         if (selinux_policycap_openperm() &&
2012             inode->i_sb->s_magic != SOCKFS_MAGIC)
2013                 av |= FILE__OPEN;
2014
2015         return av;
2016 }
2017
2018 /* Hook functions begin here. */
2019
2020 static int selinux_binder_set_context_mgr(const struct cred *mgr)
2021 {
2022         return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2023                             BINDER__SET_CONTEXT_MGR, NULL);
2024 }
2025
2026 static int selinux_binder_transaction(const struct cred *from,
2027                                       const struct cred *to)
2028 {
2029         u32 mysid = current_sid();
2030         u32 fromsid = cred_sid(from);
2031         u32 tosid = cred_sid(to);
2032         int rc;
2033
2034         if (mysid != fromsid) {
2035                 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2036                                   BINDER__IMPERSONATE, NULL);
2037                 if (rc)
2038                         return rc;
2039         }
2040
2041         return avc_has_perm(fromsid, tosid,
2042                             SECCLASS_BINDER, BINDER__CALL, NULL);
2043 }
2044
2045 static int selinux_binder_transfer_binder(const struct cred *from,
2046                                           const struct cred *to)
2047 {
2048         return avc_has_perm(cred_sid(from), cred_sid(to),
2049                             SECCLASS_BINDER, BINDER__TRANSFER,
2050                             NULL);
2051 }
2052
2053 static int selinux_binder_transfer_file(const struct cred *from,
2054                                         const struct cred *to,
2055                                         const struct file *file)
2056 {
2057         u32 sid = cred_sid(to);
2058         struct file_security_struct *fsec = selinux_file(file);
2059         struct dentry *dentry = file->f_path.dentry;
2060         struct inode_security_struct *isec;
2061         struct common_audit_data ad;
2062         int rc;
2063
2064         ad.type = LSM_AUDIT_DATA_PATH;
2065         ad.u.path = file->f_path;
2066
2067         if (sid != fsec->sid) {
2068                 rc = avc_has_perm(sid, fsec->sid,
2069                                   SECCLASS_FD,
2070                                   FD__USE,
2071                                   &ad);
2072                 if (rc)
2073                         return rc;
2074         }
2075
2076 #ifdef CONFIG_BPF_SYSCALL
2077         rc = bpf_fd_pass(file, sid);
2078         if (rc)
2079                 return rc;
2080 #endif
2081
2082         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2083                 return 0;
2084
2085         isec = backing_inode_security(dentry);
2086         return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2087                             &ad);
2088 }
2089
2090 static int selinux_ptrace_access_check(struct task_struct *child,
2091                                        unsigned int mode)
2092 {
2093         u32 sid = current_sid();
2094         u32 csid = task_sid_obj(child);
2095
2096         if (mode & PTRACE_MODE_READ)
2097                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2098                                 NULL);
2099
2100         return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2101                         NULL);
2102 }
2103
2104 static int selinux_ptrace_traceme(struct task_struct *parent)
2105 {
2106         return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2107                             SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2108 }
2109
2110 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2111                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2112 {
2113         return avc_has_perm(current_sid(), task_sid_obj(target),
2114                         SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2115 }
2116
2117 static int selinux_capset(struct cred *new, const struct cred *old,
2118                           const kernel_cap_t *effective,
2119                           const kernel_cap_t *inheritable,
2120                           const kernel_cap_t *permitted)
2121 {
2122         return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2123                             PROCESS__SETCAP, NULL);
2124 }
2125
2126 /*
2127  * (This comment used to live with the selinux_task_setuid hook,
2128  * which was removed).
2129  *
2130  * Since setuid only affects the current process, and since the SELinux
2131  * controls are not based on the Linux identity attributes, SELinux does not
2132  * need to control this operation.  However, SELinux does control the use of
2133  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2134  */
2135
2136 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2137                            int cap, unsigned int opts)
2138 {
2139         return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2140 }
2141
2142 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2143 {
2144         const struct cred *cred = current_cred();
2145         int rc = 0;
2146
2147         if (!sb)
2148                 return 0;
2149
2150         switch (cmds) {
2151         case Q_SYNC:
2152         case Q_QUOTAON:
2153         case Q_QUOTAOFF:
2154         case Q_SETINFO:
2155         case Q_SETQUOTA:
2156         case Q_XQUOTAOFF:
2157         case Q_XQUOTAON:
2158         case Q_XSETQLIM:
2159                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2160                 break;
2161         case Q_GETFMT:
2162         case Q_GETINFO:
2163         case Q_GETQUOTA:
2164         case Q_XGETQUOTA:
2165         case Q_XGETQSTAT:
2166         case Q_XGETQSTATV:
2167         case Q_XGETNEXTQUOTA:
2168                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2169                 break;
2170         default:
2171                 rc = 0;  /* let the kernel handle invalid cmds */
2172                 break;
2173         }
2174         return rc;
2175 }
2176
2177 static int selinux_quota_on(struct dentry *dentry)
2178 {
2179         const struct cred *cred = current_cred();
2180
2181         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2182 }
2183
2184 static int selinux_syslog(int type)
2185 {
2186         switch (type) {
2187         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2188         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2189                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2190                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2191         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2192         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2193         /* Set level of messages printed to console */
2194         case SYSLOG_ACTION_CONSOLE_LEVEL:
2195                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2196                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2197                                     NULL);
2198         }
2199         /* All other syslog types */
2200         return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2201                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2202 }
2203
2204 /*
2205  * Check that a process has enough memory to allocate a new virtual
2206  * mapping. 0 means there is enough memory for the allocation to
2207  * succeed and -ENOMEM implies there is not.
2208  *
2209  * Do not audit the selinux permission check, as this is applied to all
2210  * processes that allocate mappings.
2211  */
2212 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2213 {
2214         int rc, cap_sys_admin = 0;
2215
2216         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2217                                  CAP_OPT_NOAUDIT, true);
2218         if (rc == 0)
2219                 cap_sys_admin = 1;
2220
2221         return cap_sys_admin;
2222 }
2223
2224 /* binprm security operations */
2225
2226 static u32 ptrace_parent_sid(void)
2227 {
2228         u32 sid = 0;
2229         struct task_struct *tracer;
2230
2231         rcu_read_lock();
2232         tracer = ptrace_parent(current);
2233         if (tracer)
2234                 sid = task_sid_obj(tracer);
2235         rcu_read_unlock();
2236
2237         return sid;
2238 }
2239
2240 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2241                             const struct task_security_struct *old_tsec,
2242                             const struct task_security_struct *new_tsec)
2243 {
2244         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2245         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2246         int rc;
2247         u32 av;
2248
2249         if (!nnp && !nosuid)
2250                 return 0; /* neither NNP nor nosuid */
2251
2252         if (new_tsec->sid == old_tsec->sid)
2253                 return 0; /* No change in credentials */
2254
2255         /*
2256          * If the policy enables the nnp_nosuid_transition policy capability,
2257          * then we permit transitions under NNP or nosuid if the
2258          * policy allows the corresponding permission between
2259          * the old and new contexts.
2260          */
2261         if (selinux_policycap_nnp_nosuid_transition()) {
2262                 av = 0;
2263                 if (nnp)
2264                         av |= PROCESS2__NNP_TRANSITION;
2265                 if (nosuid)
2266                         av |= PROCESS2__NOSUID_TRANSITION;
2267                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2268                                   SECCLASS_PROCESS2, av, NULL);
2269                 if (!rc)
2270                         return 0;
2271         }
2272
2273         /*
2274          * We also permit NNP or nosuid transitions to bounded SIDs,
2275          * i.e. SIDs that are guaranteed to only be allowed a subset
2276          * of the permissions of the current SID.
2277          */
2278         rc = security_bounded_transition(old_tsec->sid,
2279                                          new_tsec->sid);
2280         if (!rc)
2281                 return 0;
2282
2283         /*
2284          * On failure, preserve the errno values for NNP vs nosuid.
2285          * NNP:  Operation not permitted for caller.
2286          * nosuid:  Permission denied to file.
2287          */
2288         if (nnp)
2289                 return -EPERM;
2290         return -EACCES;
2291 }
2292
2293 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2294 {
2295         const struct task_security_struct *old_tsec;
2296         struct task_security_struct *new_tsec;
2297         struct inode_security_struct *isec;
2298         struct common_audit_data ad;
2299         struct inode *inode = file_inode(bprm->file);
2300         int rc;
2301
2302         /* SELinux context only depends on initial program or script and not
2303          * the script interpreter */
2304
2305         old_tsec = selinux_cred(current_cred());
2306         new_tsec = selinux_cred(bprm->cred);
2307         isec = inode_security(inode);
2308
2309         /* Default to the current task SID. */
2310         new_tsec->sid = old_tsec->sid;
2311         new_tsec->osid = old_tsec->sid;
2312
2313         /* Reset fs, key, and sock SIDs on execve. */
2314         new_tsec->create_sid = 0;
2315         new_tsec->keycreate_sid = 0;
2316         new_tsec->sockcreate_sid = 0;
2317
2318         /*
2319          * Before policy is loaded, label any task outside kernel space
2320          * as SECINITSID_INIT, so that any userspace tasks surviving from
2321          * early boot end up with a label different from SECINITSID_KERNEL
2322          * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2323          */
2324         if (!selinux_initialized()) {
2325                 new_tsec->sid = SECINITSID_INIT;
2326                 /* also clear the exec_sid just in case */
2327                 new_tsec->exec_sid = 0;
2328                 return 0;
2329         }
2330
2331         if (old_tsec->exec_sid) {
2332                 new_tsec->sid = old_tsec->exec_sid;
2333                 /* Reset exec SID on execve. */
2334                 new_tsec->exec_sid = 0;
2335
2336                 /* Fail on NNP or nosuid if not an allowed transition. */
2337                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2338                 if (rc)
2339                         return rc;
2340         } else {
2341                 /* Check for a default transition on this program. */
2342                 rc = security_transition_sid(old_tsec->sid,
2343                                              isec->sid, SECCLASS_PROCESS, NULL,
2344                                              &new_tsec->sid);
2345                 if (rc)
2346                         return rc;
2347
2348                 /*
2349                  * Fallback to old SID on NNP or nosuid if not an allowed
2350                  * transition.
2351                  */
2352                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2353                 if (rc)
2354                         new_tsec->sid = old_tsec->sid;
2355         }
2356
2357         ad.type = LSM_AUDIT_DATA_FILE;
2358         ad.u.file = bprm->file;
2359
2360         if (new_tsec->sid == old_tsec->sid) {
2361                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2362                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2363                 if (rc)
2364                         return rc;
2365         } else {
2366                 /* Check permissions for the transition. */
2367                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2368                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2369                 if (rc)
2370                         return rc;
2371
2372                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2373                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2374                 if (rc)
2375                         return rc;
2376
2377                 /* Check for shared state */
2378                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2379                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2380                                           SECCLASS_PROCESS, PROCESS__SHARE,
2381                                           NULL);
2382                         if (rc)
2383                                 return -EPERM;
2384                 }
2385
2386                 /* Make sure that anyone attempting to ptrace over a task that
2387                  * changes its SID has the appropriate permit */
2388                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2389                         u32 ptsid = ptrace_parent_sid();
2390                         if (ptsid != 0) {
2391                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2392                                                   SECCLASS_PROCESS,
2393                                                   PROCESS__PTRACE, NULL);
2394                                 if (rc)
2395                                         return -EPERM;
2396                         }
2397                 }
2398
2399                 /* Clear any possibly unsafe personality bits on exec: */
2400                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2401
2402                 /* Enable secure mode for SIDs transitions unless
2403                    the noatsecure permission is granted between
2404                    the two SIDs, i.e. ahp returns 0. */
2405                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2406                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2407                                   NULL);
2408                 bprm->secureexec |= !!rc;
2409         }
2410
2411         return 0;
2412 }
2413
2414 static int match_file(const void *p, struct file *file, unsigned fd)
2415 {
2416         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2417 }
2418
2419 /* Derived from fs/exec.c:flush_old_files. */
2420 static inline void flush_unauthorized_files(const struct cred *cred,
2421                                             struct files_struct *files)
2422 {
2423         struct file *file, *devnull = NULL;
2424         struct tty_struct *tty;
2425         int drop_tty = 0;
2426         unsigned n;
2427
2428         tty = get_current_tty();
2429         if (tty) {
2430                 spin_lock(&tty->files_lock);
2431                 if (!list_empty(&tty->tty_files)) {
2432                         struct tty_file_private *file_priv;
2433
2434                         /* Revalidate access to controlling tty.
2435                            Use file_path_has_perm on the tty path directly
2436                            rather than using file_has_perm, as this particular
2437                            open file may belong to another process and we are
2438                            only interested in the inode-based check here. */
2439                         file_priv = list_first_entry(&tty->tty_files,
2440                                                 struct tty_file_private, list);
2441                         file = file_priv->file;
2442                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2443                                 drop_tty = 1;
2444                 }
2445                 spin_unlock(&tty->files_lock);
2446                 tty_kref_put(tty);
2447         }
2448         /* Reset controlling tty. */
2449         if (drop_tty)
2450                 no_tty();
2451
2452         /* Revalidate access to inherited open files. */
2453         n = iterate_fd(files, 0, match_file, cred);
2454         if (!n) /* none found? */
2455                 return;
2456
2457         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2458         if (IS_ERR(devnull))
2459                 devnull = NULL;
2460         /* replace all the matching ones with this */
2461         do {
2462                 replace_fd(n - 1, devnull, 0);
2463         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2464         if (devnull)
2465                 fput(devnull);
2466 }
2467
2468 /*
2469  * Prepare a process for imminent new credential changes due to exec
2470  */
2471 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2472 {
2473         struct task_security_struct *new_tsec;
2474         struct rlimit *rlim, *initrlim;
2475         int rc, i;
2476
2477         new_tsec = selinux_cred(bprm->cred);
2478         if (new_tsec->sid == new_tsec->osid)
2479                 return;
2480
2481         /* Close files for which the new task SID is not authorized. */
2482         flush_unauthorized_files(bprm->cred, current->files);
2483
2484         /* Always clear parent death signal on SID transitions. */
2485         current->pdeath_signal = 0;
2486
2487         /* Check whether the new SID can inherit resource limits from the old
2488          * SID.  If not, reset all soft limits to the lower of the current
2489          * task's hard limit and the init task's soft limit.
2490          *
2491          * Note that the setting of hard limits (even to lower them) can be
2492          * controlled by the setrlimit check.  The inclusion of the init task's
2493          * soft limit into the computation is to avoid resetting soft limits
2494          * higher than the default soft limit for cases where the default is
2495          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2496          */
2497         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2498                           PROCESS__RLIMITINH, NULL);
2499         if (rc) {
2500                 /* protect against do_prlimit() */
2501                 task_lock(current);
2502                 for (i = 0; i < RLIM_NLIMITS; i++) {
2503                         rlim = current->signal->rlim + i;
2504                         initrlim = init_task.signal->rlim + i;
2505                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2506                 }
2507                 task_unlock(current);
2508                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2509                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2510         }
2511 }
2512
2513 /*
2514  * Clean up the process immediately after the installation of new credentials
2515  * due to exec
2516  */
2517 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2518 {
2519         const struct task_security_struct *tsec = selinux_cred(current_cred());
2520         u32 osid, sid;
2521         int rc;
2522
2523         osid = tsec->osid;
2524         sid = tsec->sid;
2525
2526         if (sid == osid)
2527                 return;
2528
2529         /* Check whether the new SID can inherit signal state from the old SID.
2530          * If not, clear itimers to avoid subsequent signal generation and
2531          * flush and unblock signals.
2532          *
2533          * This must occur _after_ the task SID has been updated so that any
2534          * kill done after the flush will be checked against the new SID.
2535          */
2536         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2537         if (rc) {
2538                 clear_itimer();
2539
2540                 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2541                 if (!fatal_signal_pending(current)) {
2542                         flush_sigqueue(&current->pending);
2543                         flush_sigqueue(&current->signal->shared_pending);
2544                         flush_signal_handlers(current, 1);
2545                         sigemptyset(&current->blocked);
2546                         recalc_sigpending();
2547                 }
2548                 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2549         }
2550
2551         /* Wake up the parent if it is waiting so that it can recheck
2552          * wait permission to the new task SID. */
2553         read_lock(&tasklist_lock);
2554         __wake_up_parent(current, unrcu_pointer(current->real_parent));
2555         read_unlock(&tasklist_lock);
2556 }
2557
2558 /* superblock security operations */
2559
2560 static int selinux_sb_alloc_security(struct super_block *sb)
2561 {
2562         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2563
2564         mutex_init(&sbsec->lock);
2565         INIT_LIST_HEAD(&sbsec->isec_head);
2566         spin_lock_init(&sbsec->isec_lock);
2567         sbsec->sid = SECINITSID_UNLABELED;
2568         sbsec->def_sid = SECINITSID_FILE;
2569         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2570
2571         return 0;
2572 }
2573
2574 static inline int opt_len(const char *s)
2575 {
2576         bool open_quote = false;
2577         int len;
2578         char c;
2579
2580         for (len = 0; (c = s[len]) != '\0'; len++) {
2581                 if (c == '"')
2582                         open_quote = !open_quote;
2583                 if (c == ',' && !open_quote)
2584                         break;
2585         }
2586         return len;
2587 }
2588
2589 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2590 {
2591         char *from = options;
2592         char *to = options;
2593         bool first = true;
2594         int rc;
2595
2596         while (1) {
2597                 int len = opt_len(from);
2598                 int token;
2599                 char *arg = NULL;
2600
2601                 token = match_opt_prefix(from, len, &arg);
2602
2603                 if (token != Opt_error) {
2604                         char *p, *q;
2605
2606                         /* strip quotes */
2607                         if (arg) {
2608                                 for (p = q = arg; p < from + len; p++) {
2609                                         char c = *p;
2610                                         if (c != '"')
2611                                                 *q++ = c;
2612                                 }
2613                                 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2614                                 if (!arg) {
2615                                         rc = -ENOMEM;
2616                                         goto free_opt;
2617                                 }
2618                         }
2619                         rc = selinux_add_opt(token, arg, mnt_opts);
2620                         kfree(arg);
2621                         arg = NULL;
2622                         if (unlikely(rc)) {
2623                                 goto free_opt;
2624                         }
2625                 } else {
2626                         if (!first) {   // copy with preceding comma
2627                                 from--;
2628                                 len++;
2629                         }
2630                         if (to != from)
2631                                 memmove(to, from, len);
2632                         to += len;
2633                         first = false;
2634                 }
2635                 if (!from[len])
2636                         break;
2637                 from += len + 1;
2638         }
2639         *to = '\0';
2640         return 0;
2641
2642 free_opt:
2643         if (*mnt_opts) {
2644                 selinux_free_mnt_opts(*mnt_opts);
2645                 *mnt_opts = NULL;
2646         }
2647         return rc;
2648 }
2649
2650 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2651 {
2652         struct selinux_mnt_opts *opts = mnt_opts;
2653         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2654
2655         /*
2656          * Superblock not initialized (i.e. no options) - reject if any
2657          * options specified, otherwise accept.
2658          */
2659         if (!(sbsec->flags & SE_SBINITIALIZED))
2660                 return opts ? 1 : 0;
2661
2662         /*
2663          * Superblock initialized and no options specified - reject if
2664          * superblock has any options set, otherwise accept.
2665          */
2666         if (!opts)
2667                 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2668
2669         if (opts->fscontext_sid) {
2670                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2671                                opts->fscontext_sid))
2672                         return 1;
2673         }
2674         if (opts->context_sid) {
2675                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2676                                opts->context_sid))
2677                         return 1;
2678         }
2679         if (opts->rootcontext_sid) {
2680                 struct inode_security_struct *root_isec;
2681
2682                 root_isec = backing_inode_security(sb->s_root);
2683                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2684                                opts->rootcontext_sid))
2685                         return 1;
2686         }
2687         if (opts->defcontext_sid) {
2688                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2689                                opts->defcontext_sid))
2690                         return 1;
2691         }
2692         return 0;
2693 }
2694
2695 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2696 {
2697         struct selinux_mnt_opts *opts = mnt_opts;
2698         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2699
2700         if (!(sbsec->flags & SE_SBINITIALIZED))
2701                 return 0;
2702
2703         if (!opts)
2704                 return 0;
2705
2706         if (opts->fscontext_sid) {
2707                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2708                                opts->fscontext_sid))
2709                         goto out_bad_option;
2710         }
2711         if (opts->context_sid) {
2712                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2713                                opts->context_sid))
2714                         goto out_bad_option;
2715         }
2716         if (opts->rootcontext_sid) {
2717                 struct inode_security_struct *root_isec;
2718                 root_isec = backing_inode_security(sb->s_root);
2719                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2720                                opts->rootcontext_sid))
2721                         goto out_bad_option;
2722         }
2723         if (opts->defcontext_sid) {
2724                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2725                                opts->defcontext_sid))
2726                         goto out_bad_option;
2727         }
2728         return 0;
2729
2730 out_bad_option:
2731         pr_warn("SELinux: unable to change security options "
2732                "during remount (dev %s, type=%s)\n", sb->s_id,
2733                sb->s_type->name);
2734         return -EINVAL;
2735 }
2736
2737 static int selinux_sb_kern_mount(const struct super_block *sb)
2738 {
2739         const struct cred *cred = current_cred();
2740         struct common_audit_data ad;
2741
2742         ad.type = LSM_AUDIT_DATA_DENTRY;
2743         ad.u.dentry = sb->s_root;
2744         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2745 }
2746
2747 static int selinux_sb_statfs(struct dentry *dentry)
2748 {
2749         const struct cred *cred = current_cred();
2750         struct common_audit_data ad;
2751
2752         ad.type = LSM_AUDIT_DATA_DENTRY;
2753         ad.u.dentry = dentry->d_sb->s_root;
2754         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2755 }
2756
2757 static int selinux_mount(const char *dev_name,
2758                          const struct path *path,
2759                          const char *type,
2760                          unsigned long flags,
2761                          void *data)
2762 {
2763         const struct cred *cred = current_cred();
2764
2765         if (flags & MS_REMOUNT)
2766                 return superblock_has_perm(cred, path->dentry->d_sb,
2767                                            FILESYSTEM__REMOUNT, NULL);
2768         else
2769                 return path_has_perm(cred, path, FILE__MOUNTON);
2770 }
2771
2772 static int selinux_move_mount(const struct path *from_path,
2773                               const struct path *to_path)
2774 {
2775         const struct cred *cred = current_cred();
2776
2777         return path_has_perm(cred, to_path, FILE__MOUNTON);
2778 }
2779
2780 static int selinux_umount(struct vfsmount *mnt, int flags)
2781 {
2782         const struct cred *cred = current_cred();
2783
2784         return superblock_has_perm(cred, mnt->mnt_sb,
2785                                    FILESYSTEM__UNMOUNT, NULL);
2786 }
2787
2788 static int selinux_fs_context_submount(struct fs_context *fc,
2789                                    struct super_block *reference)
2790 {
2791         const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2792         struct selinux_mnt_opts *opts;
2793
2794         /*
2795          * Ensure that fc->security remains NULL when no options are set
2796          * as expected by selinux_set_mnt_opts().
2797          */
2798         if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2799                 return 0;
2800
2801         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2802         if (!opts)
2803                 return -ENOMEM;
2804
2805         if (sbsec->flags & FSCONTEXT_MNT)
2806                 opts->fscontext_sid = sbsec->sid;
2807         if (sbsec->flags & CONTEXT_MNT)
2808                 opts->context_sid = sbsec->mntpoint_sid;
2809         if (sbsec->flags & DEFCONTEXT_MNT)
2810                 opts->defcontext_sid = sbsec->def_sid;
2811         fc->security = opts;
2812         return 0;
2813 }
2814
2815 static int selinux_fs_context_dup(struct fs_context *fc,
2816                                   struct fs_context *src_fc)
2817 {
2818         const struct selinux_mnt_opts *src = src_fc->security;
2819
2820         if (!src)
2821                 return 0;
2822
2823         fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2824         return fc->security ? 0 : -ENOMEM;
2825 }
2826
2827 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2828         fsparam_string(CONTEXT_STR,     Opt_context),
2829         fsparam_string(DEFCONTEXT_STR,  Opt_defcontext),
2830         fsparam_string(FSCONTEXT_STR,   Opt_fscontext),
2831         fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2832         fsparam_flag  (SECLABEL_STR,    Opt_seclabel),
2833         {}
2834 };
2835
2836 static int selinux_fs_context_parse_param(struct fs_context *fc,
2837                                           struct fs_parameter *param)
2838 {
2839         struct fs_parse_result result;
2840         int opt;
2841
2842         opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2843         if (opt < 0)
2844                 return opt;
2845
2846         return selinux_add_opt(opt, param->string, &fc->security);
2847 }
2848
2849 /* inode security operations */
2850
2851 static int selinux_inode_alloc_security(struct inode *inode)
2852 {
2853         struct inode_security_struct *isec = selinux_inode(inode);
2854         u32 sid = current_sid();
2855
2856         spin_lock_init(&isec->lock);
2857         INIT_LIST_HEAD(&isec->list);
2858         isec->inode = inode;
2859         isec->sid = SECINITSID_UNLABELED;
2860         isec->sclass = SECCLASS_FILE;
2861         isec->task_sid = sid;
2862         isec->initialized = LABEL_INVALID;
2863
2864         return 0;
2865 }
2866
2867 static void selinux_inode_free_security(struct inode *inode)
2868 {
2869         inode_free_security(inode);
2870 }
2871
2872 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2873                                         const struct qstr *name,
2874                                         const char **xattr_name, void **ctx,
2875                                         u32 *ctxlen)
2876 {
2877         u32 newsid;
2878         int rc;
2879
2880         rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2881                                            d_inode(dentry->d_parent), name,
2882                                            inode_mode_to_security_class(mode),
2883                                            &newsid);
2884         if (rc)
2885                 return rc;
2886
2887         if (xattr_name)
2888                 *xattr_name = XATTR_NAME_SELINUX;
2889
2890         return security_sid_to_context(newsid, (char **)ctx,
2891                                        ctxlen);
2892 }
2893
2894 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2895                                           struct qstr *name,
2896                                           const struct cred *old,
2897                                           struct cred *new)
2898 {
2899         u32 newsid;
2900         int rc;
2901         struct task_security_struct *tsec;
2902
2903         rc = selinux_determine_inode_label(selinux_cred(old),
2904                                            d_inode(dentry->d_parent), name,
2905                                            inode_mode_to_security_class(mode),
2906                                            &newsid);
2907         if (rc)
2908                 return rc;
2909
2910         tsec = selinux_cred(new);
2911         tsec->create_sid = newsid;
2912         return 0;
2913 }
2914
2915 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2916                                        const struct qstr *qstr,
2917                                        struct xattr *xattrs, int *xattr_count)
2918 {
2919         const struct task_security_struct *tsec = selinux_cred(current_cred());
2920         struct superblock_security_struct *sbsec;
2921         struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2922         u32 newsid, clen;
2923         u16 newsclass;
2924         int rc;
2925         char *context;
2926
2927         sbsec = selinux_superblock(dir->i_sb);
2928
2929         newsid = tsec->create_sid;
2930         newsclass = inode_mode_to_security_class(inode->i_mode);
2931         rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid);
2932         if (rc)
2933                 return rc;
2934
2935         /* Possibly defer initialization to selinux_complete_init. */
2936         if (sbsec->flags & SE_SBINITIALIZED) {
2937                 struct inode_security_struct *isec = selinux_inode(inode);
2938                 isec->sclass = newsclass;
2939                 isec->sid = newsid;
2940                 isec->initialized = LABEL_INITIALIZED;
2941         }
2942
2943         if (!selinux_initialized() ||
2944             !(sbsec->flags & SBLABEL_MNT))
2945                 return -EOPNOTSUPP;
2946
2947         if (xattr) {
2948                 rc = security_sid_to_context_force(newsid,
2949                                                    &context, &clen);
2950                 if (rc)
2951                         return rc;
2952                 xattr->value = context;
2953                 xattr->value_len = clen;
2954                 xattr->name = XATTR_SELINUX_SUFFIX;
2955         }
2956
2957         return 0;
2958 }
2959
2960 static int selinux_inode_init_security_anon(struct inode *inode,
2961                                             const struct qstr *name,
2962                                             const struct inode *context_inode)
2963 {
2964         u32 sid = current_sid();
2965         struct common_audit_data ad;
2966         struct inode_security_struct *isec;
2967         int rc;
2968
2969         if (unlikely(!selinux_initialized()))
2970                 return 0;
2971
2972         isec = selinux_inode(inode);
2973
2974         /*
2975          * We only get here once per ephemeral inode.  The inode has
2976          * been initialized via inode_alloc_security but is otherwise
2977          * untouched.
2978          */
2979
2980         if (context_inode) {
2981                 struct inode_security_struct *context_isec =
2982                         selinux_inode(context_inode);
2983                 if (context_isec->initialized != LABEL_INITIALIZED) {
2984                         pr_err("SELinux:  context_inode is not initialized\n");
2985                         return -EACCES;
2986                 }
2987
2988                 isec->sclass = context_isec->sclass;
2989                 isec->sid = context_isec->sid;
2990         } else {
2991                 isec->sclass = SECCLASS_ANON_INODE;
2992                 rc = security_transition_sid(
2993                         sid, sid,
2994                         isec->sclass, name, &isec->sid);
2995                 if (rc)
2996                         return rc;
2997         }
2998
2999         isec->initialized = LABEL_INITIALIZED;
3000         /*
3001          * Now that we've initialized security, check whether we're
3002          * allowed to actually create this type of anonymous inode.
3003          */
3004
3005         ad.type = LSM_AUDIT_DATA_ANONINODE;
3006         ad.u.anonclass = name ? (const char *)name->name : "?";
3007
3008         return avc_has_perm(sid,
3009                             isec->sid,
3010                             isec->sclass,
3011                             FILE__CREATE,
3012                             &ad);
3013 }
3014
3015 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3016 {
3017         return may_create(dir, dentry, SECCLASS_FILE);
3018 }
3019
3020 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3021 {
3022         return may_link(dir, old_dentry, MAY_LINK);
3023 }
3024
3025 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3026 {
3027         return may_link(dir, dentry, MAY_UNLINK);
3028 }
3029
3030 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3031 {
3032         return may_create(dir, dentry, SECCLASS_LNK_FILE);
3033 }
3034
3035 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3036 {
3037         return may_create(dir, dentry, SECCLASS_DIR);
3038 }
3039
3040 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3041 {
3042         return may_link(dir, dentry, MAY_RMDIR);
3043 }
3044
3045 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3046 {
3047         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3048 }
3049
3050 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3051                                 struct inode *new_inode, struct dentry *new_dentry)
3052 {
3053         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3054 }
3055
3056 static int selinux_inode_readlink(struct dentry *dentry)
3057 {
3058         const struct cred *cred = current_cred();
3059
3060         return dentry_has_perm(cred, dentry, FILE__READ);
3061 }
3062
3063 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3064                                      bool rcu)
3065 {
3066         struct common_audit_data ad;
3067         struct inode_security_struct *isec;
3068         u32 sid = current_sid();
3069
3070         ad.type = LSM_AUDIT_DATA_DENTRY;
3071         ad.u.dentry = dentry;
3072         isec = inode_security_rcu(inode, rcu);
3073         if (IS_ERR(isec))
3074                 return PTR_ERR(isec);
3075
3076         return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3077 }
3078
3079 static noinline int audit_inode_permission(struct inode *inode,
3080                                            u32 perms, u32 audited, u32 denied,
3081                                            int result)
3082 {
3083         struct common_audit_data ad;
3084         struct inode_security_struct *isec = selinux_inode(inode);
3085
3086         ad.type = LSM_AUDIT_DATA_INODE;
3087         ad.u.inode = inode;
3088
3089         return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3090                             audited, denied, result, &ad);
3091 }
3092
3093 static int selinux_inode_permission(struct inode *inode, int mask)
3094 {
3095         u32 perms;
3096         bool from_access;
3097         bool no_block = mask & MAY_NOT_BLOCK;
3098         struct inode_security_struct *isec;
3099         u32 sid = current_sid();
3100         struct av_decision avd;
3101         int rc, rc2;
3102         u32 audited, denied;
3103
3104         from_access = mask & MAY_ACCESS;
3105         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3106
3107         /* No permission to check.  Existence test. */
3108         if (!mask)
3109                 return 0;
3110
3111         if (unlikely(IS_PRIVATE(inode)))
3112                 return 0;
3113
3114         perms = file_mask_to_av(inode->i_mode, mask);
3115
3116         isec = inode_security_rcu(inode, no_block);
3117         if (IS_ERR(isec))
3118                 return PTR_ERR(isec);
3119
3120         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3121                                   &avd);
3122         audited = avc_audit_required(perms, &avd, rc,
3123                                      from_access ? FILE__AUDIT_ACCESS : 0,
3124                                      &denied);
3125         if (likely(!audited))
3126                 return rc;
3127
3128         rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3129         if (rc2)
3130                 return rc2;
3131         return rc;
3132 }
3133
3134 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
3135                                  struct iattr *iattr)
3136 {
3137         const struct cred *cred = current_cred();
3138         struct inode *inode = d_backing_inode(dentry);
3139         unsigned int ia_valid = iattr->ia_valid;
3140         __u32 av = FILE__WRITE;
3141
3142         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3143         if (ia_valid & ATTR_FORCE) {
3144                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3145                               ATTR_FORCE);
3146                 if (!ia_valid)
3147                         return 0;
3148         }
3149
3150         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3151                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3152                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3153
3154         if (selinux_policycap_openperm() &&
3155             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3156             (ia_valid & ATTR_SIZE) &&
3157             !(ia_valid & ATTR_FILE))
3158                 av |= FILE__OPEN;
3159
3160         return dentry_has_perm(cred, dentry, av);
3161 }
3162
3163 static int selinux_inode_getattr(const struct path *path)
3164 {
3165         return path_has_perm(current_cred(), path, FILE__GETATTR);
3166 }
3167
3168 static bool has_cap_mac_admin(bool audit)
3169 {
3170         const struct cred *cred = current_cred();
3171         unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3172
3173         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3174                 return false;
3175         if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3176                 return false;
3177         return true;
3178 }
3179
3180 static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3181                                   struct dentry *dentry, const char *name,
3182                                   const void *value, size_t size, int flags)
3183 {
3184         struct inode *inode = d_backing_inode(dentry);
3185         struct inode_security_struct *isec;
3186         struct superblock_security_struct *sbsec;
3187         struct common_audit_data ad;
3188         u32 newsid, sid = current_sid();
3189         int rc = 0;
3190
3191         if (strcmp(name, XATTR_NAME_SELINUX)) {
3192                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3193                 if (rc)
3194                         return rc;
3195
3196                 /* Not an attribute we recognize, so just check the
3197                    ordinary setattr permission. */
3198                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3199         }
3200
3201         if (!selinux_initialized())
3202                 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3203
3204         sbsec = selinux_superblock(inode->i_sb);
3205         if (!(sbsec->flags & SBLABEL_MNT))
3206                 return -EOPNOTSUPP;
3207
3208         if (!inode_owner_or_capable(idmap, inode))
3209                 return -EPERM;
3210
3211         ad.type = LSM_AUDIT_DATA_DENTRY;
3212         ad.u.dentry = dentry;
3213
3214         isec = backing_inode_security(dentry);
3215         rc = avc_has_perm(sid, isec->sid, isec->sclass,
3216                           FILE__RELABELFROM, &ad);
3217         if (rc)
3218                 return rc;
3219
3220         rc = security_context_to_sid(value, size, &newsid,
3221                                      GFP_KERNEL);
3222         if (rc == -EINVAL) {
3223                 if (!has_cap_mac_admin(true)) {
3224                         struct audit_buffer *ab;
3225                         size_t audit_size;
3226
3227                         /* We strip a nul only if it is at the end, otherwise the
3228                          * context contains a nul and we should audit that */
3229                         if (value) {
3230                                 const char *str = value;
3231
3232                                 if (str[size - 1] == '\0')
3233                                         audit_size = size - 1;
3234                                 else
3235                                         audit_size = size;
3236                         } else {
3237                                 audit_size = 0;
3238                         }
3239                         ab = audit_log_start(audit_context(),
3240                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3241                         if (!ab)
3242                                 return rc;
3243                         audit_log_format(ab, "op=setxattr invalid_context=");
3244                         audit_log_n_untrustedstring(ab, value, audit_size);
3245                         audit_log_end(ab);
3246
3247                         return rc;
3248                 }
3249                 rc = security_context_to_sid_force(value,
3250                                                    size, &newsid);
3251         }
3252         if (rc)
3253                 return rc;
3254
3255         rc = avc_has_perm(sid, newsid, isec->sclass,
3256                           FILE__RELABELTO, &ad);
3257         if (rc)
3258                 return rc;
3259
3260         rc = security_validate_transition(isec->sid, newsid,
3261                                           sid, isec->sclass);
3262         if (rc)
3263                 return rc;
3264
3265         return avc_has_perm(newsid,
3266                             sbsec->sid,
3267                             SECCLASS_FILESYSTEM,
3268                             FILESYSTEM__ASSOCIATE,
3269                             &ad);
3270 }
3271
3272 static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3273                                  struct dentry *dentry, const char *acl_name,
3274                                  struct posix_acl *kacl)
3275 {
3276         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3277 }
3278
3279 static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3280                                  struct dentry *dentry, const char *acl_name)
3281 {
3282         return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3283 }
3284
3285 static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3286                                     struct dentry *dentry, const char *acl_name)
3287 {
3288         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3289 }
3290
3291 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3292                                         const void *value, size_t size,
3293                                         int flags)
3294 {
3295         struct inode *inode = d_backing_inode(dentry);
3296         struct inode_security_struct *isec;
3297         u32 newsid;
3298         int rc;
3299
3300         if (strcmp(name, XATTR_NAME_SELINUX)) {
3301                 /* Not an attribute we recognize, so nothing to do. */
3302                 return;
3303         }
3304
3305         if (!selinux_initialized()) {
3306                 /* If we haven't even been initialized, then we can't validate
3307                  * against a policy, so leave the label as invalid. It may
3308                  * resolve to a valid label on the next revalidation try if
3309                  * we've since initialized.
3310                  */
3311                 return;
3312         }
3313
3314         rc = security_context_to_sid_force(value, size,
3315                                            &newsid);
3316         if (rc) {
3317                 pr_err("SELinux:  unable to map context to SID"
3318                        "for (%s, %lu), rc=%d\n",
3319                        inode->i_sb->s_id, inode->i_ino, -rc);
3320                 return;
3321         }
3322
3323         isec = backing_inode_security(dentry);
3324         spin_lock(&isec->lock);
3325         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3326         isec->sid = newsid;
3327         isec->initialized = LABEL_INITIALIZED;
3328         spin_unlock(&isec->lock);
3329 }
3330
3331 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3332 {
3333         const struct cred *cred = current_cred();
3334
3335         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3336 }
3337
3338 static int selinux_inode_listxattr(struct dentry *dentry)
3339 {
3340         const struct cred *cred = current_cred();
3341
3342         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3343 }
3344
3345 static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3346                                      struct dentry *dentry, const char *name)
3347 {
3348         if (strcmp(name, XATTR_NAME_SELINUX)) {
3349                 int rc = cap_inode_removexattr(idmap, dentry, name);
3350                 if (rc)
3351                         return rc;
3352
3353                 /* Not an attribute we recognize, so just check the
3354                    ordinary setattr permission. */
3355                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3356         }
3357
3358         if (!selinux_initialized())
3359                 return 0;
3360
3361         /* No one is allowed to remove a SELinux security label.
3362            You can change the label, but all data must be labeled. */
3363         return -EACCES;
3364 }
3365
3366 static int selinux_path_notify(const struct path *path, u64 mask,
3367                                                 unsigned int obj_type)
3368 {
3369         int ret;
3370         u32 perm;
3371
3372         struct common_audit_data ad;
3373
3374         ad.type = LSM_AUDIT_DATA_PATH;
3375         ad.u.path = *path;
3376
3377         /*
3378          * Set permission needed based on the type of mark being set.
3379          * Performs an additional check for sb watches.
3380          */
3381         switch (obj_type) {
3382         case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3383                 perm = FILE__WATCH_MOUNT;
3384                 break;
3385         case FSNOTIFY_OBJ_TYPE_SB:
3386                 perm = FILE__WATCH_SB;
3387                 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3388                                                 FILESYSTEM__WATCH, &ad);
3389                 if (ret)
3390                         return ret;
3391                 break;
3392         case FSNOTIFY_OBJ_TYPE_INODE:
3393                 perm = FILE__WATCH;
3394                 break;
3395         default:
3396                 return -EINVAL;
3397         }
3398
3399         /* blocking watches require the file:watch_with_perm permission */
3400         if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3401                 perm |= FILE__WATCH_WITH_PERM;
3402
3403         /* watches on read-like events need the file:watch_reads permission */
3404         if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3405                 perm |= FILE__WATCH_READS;
3406
3407         return path_has_perm(current_cred(), path, perm);
3408 }
3409
3410 /*
3411  * Copy the inode security context value to the user.
3412  *
3413  * Permission check is handled by selinux_inode_getxattr hook.
3414  */
3415 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3416                                      struct inode *inode, const char *name,
3417                                      void **buffer, bool alloc)
3418 {
3419         u32 size;
3420         int error;
3421         char *context = NULL;
3422         struct inode_security_struct *isec;
3423
3424         /*
3425          * If we're not initialized yet, then we can't validate contexts, so
3426          * just let vfs_getxattr fall back to using the on-disk xattr.
3427          */
3428         if (!selinux_initialized() ||
3429             strcmp(name, XATTR_SELINUX_SUFFIX))
3430                 return -EOPNOTSUPP;
3431
3432         /*
3433          * If the caller has CAP_MAC_ADMIN, then get the raw context
3434          * value even if it is not defined by current policy; otherwise,
3435          * use the in-core value under current policy.
3436          * Use the non-auditing forms of the permission checks since
3437          * getxattr may be called by unprivileged processes commonly
3438          * and lack of permission just means that we fall back to the
3439          * in-core context value, not a denial.
3440          */
3441         isec = inode_security(inode);
3442         if (has_cap_mac_admin(false))
3443                 error = security_sid_to_context_force(isec->sid, &context,
3444                                                       &size);
3445         else
3446                 error = security_sid_to_context(isec->sid,
3447                                                 &context, &size);
3448         if (error)
3449                 return error;
3450         error = size;
3451         if (alloc) {
3452                 *buffer = context;
3453                 goto out_nofree;
3454         }
3455         kfree(context);
3456 out_nofree:
3457         return error;
3458 }
3459
3460 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3461                                      const void *value, size_t size, int flags)
3462 {
3463         struct inode_security_struct *isec = inode_security_novalidate(inode);
3464         struct superblock_security_struct *sbsec;
3465         u32 newsid;
3466         int rc;
3467
3468         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3469                 return -EOPNOTSUPP;
3470
3471         sbsec = selinux_superblock(inode->i_sb);
3472         if (!(sbsec->flags & SBLABEL_MNT))
3473                 return -EOPNOTSUPP;
3474
3475         if (!value || !size)
3476                 return -EACCES;
3477
3478         rc = security_context_to_sid(value, size, &newsid,
3479                                      GFP_KERNEL);
3480         if (rc)
3481                 return rc;
3482
3483         spin_lock(&isec->lock);
3484         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3485         isec->sid = newsid;
3486         isec->initialized = LABEL_INITIALIZED;
3487         spin_unlock(&isec->lock);
3488         return 0;
3489 }
3490
3491 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3492 {
3493         const int len = sizeof(XATTR_NAME_SELINUX);
3494
3495         if (!selinux_initialized())
3496                 return 0;
3497
3498         if (buffer && len <= buffer_size)
3499                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3500         return len;
3501 }
3502
3503 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3504 {
3505         struct inode_security_struct *isec = inode_security_novalidate(inode);
3506         *secid = isec->sid;
3507 }
3508
3509 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3510 {
3511         u32 sid;
3512         struct task_security_struct *tsec;
3513         struct cred *new_creds = *new;
3514
3515         if (new_creds == NULL) {
3516                 new_creds = prepare_creds();
3517                 if (!new_creds)
3518                         return -ENOMEM;
3519         }
3520
3521         tsec = selinux_cred(new_creds);
3522         /* Get label from overlay inode and set it in create_sid */
3523         selinux_inode_getsecid(d_inode(src), &sid);
3524         tsec->create_sid = sid;
3525         *new = new_creds;
3526         return 0;
3527 }
3528
3529 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name)
3530 {
3531         /* The copy_up hook above sets the initial context on an inode, but we
3532          * don't then want to overwrite it by blindly copying all the lower
3533          * xattrs up.  Instead, filter out SELinux-related xattrs following
3534          * policy load.
3535          */
3536         if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0)
3537                 return 1; /* Discard */
3538         /*
3539          * Any other attribute apart from SELINUX is not claimed, supported
3540          * by selinux.
3541          */
3542         return -EOPNOTSUPP;
3543 }
3544
3545 /* kernfs node operations */
3546
3547 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3548                                         struct kernfs_node *kn)
3549 {
3550         const struct task_security_struct *tsec = selinux_cred(current_cred());
3551         u32 parent_sid, newsid, clen;
3552         int rc;
3553         char *context;
3554
3555         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3556         if (rc == -ENODATA)
3557                 return 0;
3558         else if (rc < 0)
3559                 return rc;
3560
3561         clen = (u32)rc;
3562         context = kmalloc(clen, GFP_KERNEL);
3563         if (!context)
3564                 return -ENOMEM;
3565
3566         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3567         if (rc < 0) {
3568                 kfree(context);
3569                 return rc;
3570         }
3571
3572         rc = security_context_to_sid(context, clen, &parent_sid,
3573                                      GFP_KERNEL);
3574         kfree(context);
3575         if (rc)
3576                 return rc;
3577
3578         if (tsec->create_sid) {
3579                 newsid = tsec->create_sid;
3580         } else {
3581                 u16 secclass = inode_mode_to_security_class(kn->mode);
3582                 struct qstr q;
3583
3584                 q.name = kn->name;
3585                 q.hash_len = hashlen_string(kn_dir, kn->name);
3586
3587                 rc = security_transition_sid(tsec->sid,
3588                                              parent_sid, secclass, &q,
3589                                              &newsid);
3590                 if (rc)
3591                         return rc;
3592         }
3593
3594         rc = security_sid_to_context_force(newsid,
3595                                            &context, &clen);
3596         if (rc)
3597                 return rc;
3598
3599         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3600                               XATTR_CREATE);
3601         kfree(context);
3602         return rc;
3603 }
3604
3605
3606 /* file security operations */
3607
3608 static int selinux_revalidate_file_permission(struct file *file, int mask)
3609 {
3610         const struct cred *cred = current_cred();
3611         struct inode *inode = file_inode(file);
3612
3613         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3614         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3615                 mask |= MAY_APPEND;
3616
3617         return file_has_perm(cred, file,
3618                              file_mask_to_av(inode->i_mode, mask));
3619 }
3620
3621 static int selinux_file_permission(struct file *file, int mask)
3622 {
3623         struct inode *inode = file_inode(file);
3624         struct file_security_struct *fsec = selinux_file(file);
3625         struct inode_security_struct *isec;
3626         u32 sid = current_sid();
3627
3628         if (!mask)
3629                 /* No permission to check.  Existence test. */
3630                 return 0;
3631
3632         isec = inode_security(inode);
3633         if (sid == fsec->sid && fsec->isid == isec->sid &&
3634             fsec->pseqno == avc_policy_seqno())
3635                 /* No change since file_open check. */
3636                 return 0;
3637
3638         return selinux_revalidate_file_permission(file, mask);
3639 }
3640
3641 static int selinux_file_alloc_security(struct file *file)
3642 {
3643         struct file_security_struct *fsec = selinux_file(file);
3644         u32 sid = current_sid();
3645
3646         fsec->sid = sid;
3647         fsec->fown_sid = sid;
3648
3649         return 0;
3650 }
3651
3652 /*
3653  * Check whether a task has the ioctl permission and cmd
3654  * operation to an inode.
3655  */
3656 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3657                 u32 requested, u16 cmd)
3658 {
3659         struct common_audit_data ad;
3660         struct file_security_struct *fsec = selinux_file(file);
3661         struct inode *inode = file_inode(file);
3662         struct inode_security_struct *isec;
3663         struct lsm_ioctlop_audit ioctl;
3664         u32 ssid = cred_sid(cred);
3665         int rc;
3666         u8 driver = cmd >> 8;
3667         u8 xperm = cmd & 0xff;
3668
3669         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3670         ad.u.op = &ioctl;
3671         ad.u.op->cmd = cmd;
3672         ad.u.op->path = file->f_path;
3673
3674         if (ssid != fsec->sid) {
3675                 rc = avc_has_perm(ssid, fsec->sid,
3676                                 SECCLASS_FD,
3677                                 FD__USE,
3678                                 &ad);
3679                 if (rc)
3680                         goto out;
3681         }
3682
3683         if (unlikely(IS_PRIVATE(inode)))
3684                 return 0;
3685
3686         isec = inode_security(inode);
3687         rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3688                                     requested, driver, xperm, &ad);
3689 out:
3690         return rc;
3691 }
3692
3693 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3694                               unsigned long arg)
3695 {
3696         const struct cred *cred = current_cred();
3697         int error = 0;
3698
3699         switch (cmd) {
3700         case FIONREAD:
3701         case FIBMAP:
3702         case FIGETBSZ:
3703         case FS_IOC_GETFLAGS:
3704         case FS_IOC_GETVERSION:
3705                 error = file_has_perm(cred, file, FILE__GETATTR);
3706                 break;
3707
3708         case FS_IOC_SETFLAGS:
3709         case FS_IOC_SETVERSION:
3710                 error = file_has_perm(cred, file, FILE__SETATTR);
3711                 break;
3712
3713         /* sys_ioctl() checks */
3714         case FIONBIO:
3715         case FIOASYNC:
3716                 error = file_has_perm(cred, file, 0);
3717                 break;
3718
3719         case KDSKBENT:
3720         case KDSKBSENT:
3721                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3722                                             CAP_OPT_NONE, true);
3723                 break;
3724
3725         case FIOCLEX:
3726         case FIONCLEX:
3727                 if (!selinux_policycap_ioctl_skip_cloexec())
3728                         error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3729                 break;
3730
3731         /* default case assumes that the command will go
3732          * to the file's ioctl() function.
3733          */
3734         default:
3735                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3736         }
3737         return error;
3738 }
3739
3740 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3741                               unsigned long arg)
3742 {
3743         /*
3744          * If we are in a 64-bit kernel running 32-bit userspace, we need to
3745          * make sure we don't compare 32-bit flags to 64-bit flags.
3746          */
3747         switch (cmd) {
3748         case FS_IOC32_GETFLAGS:
3749                 cmd = FS_IOC_GETFLAGS;
3750                 break;
3751         case FS_IOC32_SETFLAGS:
3752                 cmd = FS_IOC_SETFLAGS;
3753                 break;
3754         case FS_IOC32_GETVERSION:
3755                 cmd = FS_IOC_GETVERSION;
3756                 break;
3757         case FS_IOC32_SETVERSION:
3758                 cmd = FS_IOC_SETVERSION;
3759                 break;
3760         default:
3761                 break;
3762         }
3763
3764         return selinux_file_ioctl(file, cmd, arg);
3765 }
3766
3767 static int default_noexec __ro_after_init;
3768
3769 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3770 {
3771         const struct cred *cred = current_cred();
3772         u32 sid = cred_sid(cred);
3773         int rc = 0;
3774
3775         if (default_noexec &&
3776             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3777                                    (!shared && (prot & PROT_WRITE)))) {
3778                 /*
3779                  * We are making executable an anonymous mapping or a
3780                  * private file mapping that will also be writable.
3781                  * This has an additional check.
3782                  */
3783                 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3784                                   PROCESS__EXECMEM, NULL);
3785                 if (rc)
3786                         goto error;
3787         }
3788
3789         if (file) {
3790                 /* read access is always possible with a mapping */
3791                 u32 av = FILE__READ;
3792
3793                 /* write access only matters if the mapping is shared */
3794                 if (shared && (prot & PROT_WRITE))
3795                         av |= FILE__WRITE;
3796
3797                 if (prot & PROT_EXEC)
3798                         av |= FILE__EXECUTE;
3799
3800                 return file_has_perm(cred, file, av);
3801         }
3802
3803 error:
3804         return rc;
3805 }
3806
3807 static int selinux_mmap_addr(unsigned long addr)
3808 {
3809         int rc = 0;
3810
3811         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3812                 u32 sid = current_sid();
3813                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3814                                   MEMPROTECT__MMAP_ZERO, NULL);
3815         }
3816
3817         return rc;
3818 }
3819
3820 static int selinux_mmap_file(struct file *file,
3821                              unsigned long reqprot __always_unused,
3822                              unsigned long prot, unsigned long flags)
3823 {
3824         struct common_audit_data ad;
3825         int rc;
3826
3827         if (file) {
3828                 ad.type = LSM_AUDIT_DATA_FILE;
3829                 ad.u.file = file;
3830                 rc = inode_has_perm(current_cred(), file_inode(file),
3831                                     FILE__MAP, &ad);
3832                 if (rc)
3833                         return rc;
3834         }
3835
3836         return file_map_prot_check(file, prot,
3837                                    (flags & MAP_TYPE) == MAP_SHARED);
3838 }
3839
3840 static int selinux_file_mprotect(struct vm_area_struct *vma,
3841                                  unsigned long reqprot __always_unused,
3842                                  unsigned long prot)
3843 {
3844         const struct cred *cred = current_cred();
3845         u32 sid = cred_sid(cred);
3846
3847         if (default_noexec &&
3848             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3849                 int rc = 0;
3850                 if (vma_is_initial_heap(vma)) {
3851                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3852                                           PROCESS__EXECHEAP, NULL);
3853                 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3854                             vma_is_stack_for_current(vma))) {
3855                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3856                                           PROCESS__EXECSTACK, NULL);
3857                 } else if (vma->vm_file && vma->anon_vma) {
3858                         /*
3859                          * We are making executable a file mapping that has
3860                          * had some COW done. Since pages might have been
3861                          * written, check ability to execute the possibly
3862                          * modified content.  This typically should only
3863                          * occur for text relocations.
3864                          */
3865                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3866                 }
3867                 if (rc)
3868                         return rc;
3869         }
3870
3871         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3872 }
3873
3874 static int selinux_file_lock(struct file *file, unsigned int cmd)
3875 {
3876         const struct cred *cred = current_cred();
3877
3878         return file_has_perm(cred, file, FILE__LOCK);
3879 }
3880
3881 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3882                               unsigned long arg)
3883 {
3884         const struct cred *cred = current_cred();
3885         int err = 0;
3886
3887         switch (cmd) {
3888         case F_SETFL:
3889                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3890                         err = file_has_perm(cred, file, FILE__WRITE);
3891                         break;
3892                 }
3893                 fallthrough;
3894         case F_SETOWN:
3895         case F_SETSIG:
3896         case F_GETFL:
3897         case F_GETOWN:
3898         case F_GETSIG:
3899         case F_GETOWNER_UIDS:
3900                 /* Just check FD__USE permission */
3901                 err = file_has_perm(cred, file, 0);
3902                 break;
3903         case F_GETLK:
3904         case F_SETLK:
3905         case F_SETLKW:
3906         case F_OFD_GETLK:
3907         case F_OFD_SETLK:
3908         case F_OFD_SETLKW:
3909 #if BITS_PER_LONG == 32
3910         case F_GETLK64:
3911         case F_SETLK64:
3912         case F_SETLKW64:
3913 #endif
3914                 err = file_has_perm(cred, file, FILE__LOCK);
3915                 break;
3916         }
3917
3918         return err;
3919 }
3920
3921 static void selinux_file_set_fowner(struct file *file)
3922 {
3923         struct file_security_struct *fsec;
3924
3925         fsec = selinux_file(file);
3926         fsec->fown_sid = current_sid();
3927 }
3928
3929 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3930                                        struct fown_struct *fown, int signum)
3931 {
3932         struct file *file;
3933         u32 sid = task_sid_obj(tsk);
3934         u32 perm;
3935         struct file_security_struct *fsec;
3936
3937         /* struct fown_struct is never outside the context of a struct file */
3938         file = container_of(fown, struct file, f_owner);
3939
3940         fsec = selinux_file(file);
3941
3942         if (!signum)
3943                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3944         else
3945                 perm = signal_to_av(signum);
3946
3947         return avc_has_perm(fsec->fown_sid, sid,
3948                             SECCLASS_PROCESS, perm, NULL);
3949 }
3950
3951 static int selinux_file_receive(struct file *file)
3952 {
3953         const struct cred *cred = current_cred();
3954
3955         return file_has_perm(cred, file, file_to_av(file));
3956 }
3957
3958 static int selinux_file_open(struct file *file)
3959 {
3960         struct file_security_struct *fsec;
3961         struct inode_security_struct *isec;
3962
3963         fsec = selinux_file(file);
3964         isec = inode_security(file_inode(file));
3965         /*
3966          * Save inode label and policy sequence number
3967          * at open-time so that selinux_file_permission
3968          * can determine whether revalidation is necessary.
3969          * Task label is already saved in the file security
3970          * struct as its SID.
3971          */
3972         fsec->isid = isec->sid;
3973         fsec->pseqno = avc_policy_seqno();
3974         /*
3975          * Since the inode label or policy seqno may have changed
3976          * between the selinux_inode_permission check and the saving
3977          * of state above, recheck that access is still permitted.
3978          * Otherwise, access might never be revalidated against the
3979          * new inode label or new policy.
3980          * This check is not redundant - do not remove.
3981          */
3982         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3983 }
3984
3985 /* task security operations */
3986
3987 static int selinux_task_alloc(struct task_struct *task,
3988                               unsigned long clone_flags)
3989 {
3990         u32 sid = current_sid();
3991
3992         return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3993 }
3994
3995 /*
3996  * prepare a new set of credentials for modification
3997  */
3998 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3999                                 gfp_t gfp)
4000 {
4001         const struct task_security_struct *old_tsec = selinux_cred(old);
4002         struct task_security_struct *tsec = selinux_cred(new);
4003
4004         *tsec = *old_tsec;
4005         return 0;
4006 }
4007
4008 /*
4009  * transfer the SELinux data to a blank set of creds
4010  */
4011 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4012 {
4013         const struct task_security_struct *old_tsec = selinux_cred(old);
4014         struct task_security_struct *tsec = selinux_cred(new);
4015
4016         *tsec = *old_tsec;
4017 }
4018
4019 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4020 {
4021         *secid = cred_sid(c);
4022 }
4023
4024 /*
4025  * set the security data for a kernel service
4026  * - all the creation contexts are set to unlabelled
4027  */
4028 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4029 {
4030         struct task_security_struct *tsec = selinux_cred(new);
4031         u32 sid = current_sid();
4032         int ret;
4033
4034         ret = avc_has_perm(sid, secid,
4035                            SECCLASS_KERNEL_SERVICE,
4036                            KERNEL_SERVICE__USE_AS_OVERRIDE,
4037                            NULL);
4038         if (ret == 0) {
4039                 tsec->sid = secid;
4040                 tsec->create_sid = 0;
4041                 tsec->keycreate_sid = 0;
4042                 tsec->sockcreate_sid = 0;
4043         }
4044         return ret;
4045 }
4046
4047 /*
4048  * set the file creation context in a security record to the same as the
4049  * objective context of the specified inode
4050  */
4051 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4052 {
4053         struct inode_security_struct *isec = inode_security(inode);
4054         struct task_security_struct *tsec = selinux_cred(new);
4055         u32 sid = current_sid();
4056         int ret;
4057
4058         ret = avc_has_perm(sid, isec->sid,
4059                            SECCLASS_KERNEL_SERVICE,
4060                            KERNEL_SERVICE__CREATE_FILES_AS,
4061                            NULL);
4062
4063         if (ret == 0)
4064                 tsec->create_sid = isec->sid;
4065         return ret;
4066 }
4067
4068 static int selinux_kernel_module_request(char *kmod_name)
4069 {
4070         struct common_audit_data ad;
4071
4072         ad.type = LSM_AUDIT_DATA_KMOD;
4073         ad.u.kmod_name = kmod_name;
4074
4075         return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4076                             SYSTEM__MODULE_REQUEST, &ad);
4077 }
4078
4079 static int selinux_kernel_module_from_file(struct file *file)
4080 {
4081         struct common_audit_data ad;
4082         struct inode_security_struct *isec;
4083         struct file_security_struct *fsec;
4084         u32 sid = current_sid();
4085         int rc;
4086
4087         /* init_module */
4088         if (file == NULL)
4089                 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4090                                         SYSTEM__MODULE_LOAD, NULL);
4091
4092         /* finit_module */
4093
4094         ad.type = LSM_AUDIT_DATA_FILE;
4095         ad.u.file = file;
4096
4097         fsec = selinux_file(file);
4098         if (sid != fsec->sid) {
4099                 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4100                 if (rc)
4101                         return rc;
4102         }
4103
4104         isec = inode_security(file_inode(file));
4105         return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4106                                 SYSTEM__MODULE_LOAD, &ad);
4107 }
4108
4109 static int selinux_kernel_read_file(struct file *file,
4110                                     enum kernel_read_file_id id,
4111                                     bool contents)
4112 {
4113         int rc = 0;
4114
4115         switch (id) {
4116         case READING_MODULE:
4117                 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4118                 break;
4119         default:
4120                 break;
4121         }
4122
4123         return rc;
4124 }
4125
4126 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4127 {
4128         int rc = 0;
4129
4130         switch (id) {
4131         case LOADING_MODULE:
4132                 rc = selinux_kernel_module_from_file(NULL);
4133                 break;
4134         default:
4135                 break;
4136         }
4137
4138         return rc;
4139 }
4140
4141 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4142 {
4143         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4144                             PROCESS__SETPGID, NULL);
4145 }
4146
4147 static int selinux_task_getpgid(struct task_struct *p)
4148 {
4149         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4150                             PROCESS__GETPGID, NULL);
4151 }
4152
4153 static int selinux_task_getsid(struct task_struct *p)
4154 {
4155         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4156                             PROCESS__GETSESSION, NULL);
4157 }
4158
4159 static void selinux_current_getsecid_subj(u32 *secid)
4160 {
4161         *secid = current_sid();
4162 }
4163
4164 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4165 {
4166         *secid = task_sid_obj(p);
4167 }
4168
4169 static int selinux_task_setnice(struct task_struct *p, int nice)
4170 {
4171         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4172                             PROCESS__SETSCHED, NULL);
4173 }
4174
4175 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4176 {
4177         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4178                             PROCESS__SETSCHED, NULL);
4179 }
4180
4181 static int selinux_task_getioprio(struct task_struct *p)
4182 {
4183         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4184                             PROCESS__GETSCHED, NULL);
4185 }
4186
4187 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4188                                 unsigned int flags)
4189 {
4190         u32 av = 0;
4191
4192         if (!flags)
4193                 return 0;
4194         if (flags & LSM_PRLIMIT_WRITE)
4195                 av |= PROCESS__SETRLIMIT;
4196         if (flags & LSM_PRLIMIT_READ)
4197                 av |= PROCESS__GETRLIMIT;
4198         return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4199                             SECCLASS_PROCESS, av, NULL);
4200 }
4201
4202 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4203                 struct rlimit *new_rlim)
4204 {
4205         struct rlimit *old_rlim = p->signal->rlim + resource;
4206
4207         /* Control the ability to change the hard limit (whether
4208            lowering or raising it), so that the hard limit can
4209            later be used as a safe reset point for the soft limit
4210            upon context transitions.  See selinux_bprm_committing_creds. */
4211         if (old_rlim->rlim_max != new_rlim->rlim_max)
4212                 return avc_has_perm(current_sid(), task_sid_obj(p),
4213                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4214
4215         return 0;
4216 }
4217
4218 static int selinux_task_setscheduler(struct task_struct *p)
4219 {
4220         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4221                             PROCESS__SETSCHED, NULL);
4222 }
4223
4224 static int selinux_task_getscheduler(struct task_struct *p)
4225 {
4226         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4227                             PROCESS__GETSCHED, NULL);
4228 }
4229
4230 static int selinux_task_movememory(struct task_struct *p)
4231 {
4232         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4233                             PROCESS__SETSCHED, NULL);
4234 }
4235
4236 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4237                                 int sig, const struct cred *cred)
4238 {
4239         u32 secid;
4240         u32 perm;
4241
4242         if (!sig)
4243                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4244         else
4245                 perm = signal_to_av(sig);
4246         if (!cred)
4247                 secid = current_sid();
4248         else
4249                 secid = cred_sid(cred);
4250         return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4251 }
4252
4253 static void selinux_task_to_inode(struct task_struct *p,
4254                                   struct inode *inode)
4255 {
4256         struct inode_security_struct *isec = selinux_inode(inode);
4257         u32 sid = task_sid_obj(p);
4258
4259         spin_lock(&isec->lock);
4260         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4261         isec->sid = sid;
4262         isec->initialized = LABEL_INITIALIZED;
4263         spin_unlock(&isec->lock);
4264 }
4265
4266 static int selinux_userns_create(const struct cred *cred)
4267 {
4268         u32 sid = current_sid();
4269
4270         return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4271                         USER_NAMESPACE__CREATE, NULL);
4272 }
4273
4274 /* Returns error only if unable to parse addresses */
4275 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4276                         struct common_audit_data *ad, u8 *proto)
4277 {
4278         int offset, ihlen, ret = -EINVAL;
4279         struct iphdr _iph, *ih;
4280
4281         offset = skb_network_offset(skb);
4282         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4283         if (ih == NULL)
4284                 goto out;
4285
4286         ihlen = ih->ihl * 4;
4287         if (ihlen < sizeof(_iph))
4288                 goto out;
4289
4290         ad->u.net->v4info.saddr = ih->saddr;
4291         ad->u.net->v4info.daddr = ih->daddr;
4292         ret = 0;
4293
4294         if (proto)
4295                 *proto = ih->protocol;
4296
4297         switch (ih->protocol) {
4298         case IPPROTO_TCP: {
4299                 struct tcphdr _tcph, *th;
4300
4301                 if (ntohs(ih->frag_off) & IP_OFFSET)
4302                         break;
4303
4304                 offset += ihlen;
4305                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4306                 if (th == NULL)
4307                         break;
4308
4309                 ad->u.net->sport = th->source;
4310                 ad->u.net->dport = th->dest;
4311                 break;
4312         }
4313
4314         case IPPROTO_UDP: {
4315                 struct udphdr _udph, *uh;
4316
4317                 if (ntohs(ih->frag_off) & IP_OFFSET)
4318                         break;
4319
4320                 offset += ihlen;
4321                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4322                 if (uh == NULL)
4323                         break;
4324
4325                 ad->u.net->sport = uh->source;
4326                 ad->u.net->dport = uh->dest;
4327                 break;
4328         }
4329
4330         case IPPROTO_DCCP: {
4331                 struct dccp_hdr _dccph, *dh;
4332
4333                 if (ntohs(ih->frag_off) & IP_OFFSET)
4334                         break;
4335
4336                 offset += ihlen;
4337                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4338                 if (dh == NULL)
4339                         break;
4340
4341                 ad->u.net->sport = dh->dccph_sport;
4342                 ad->u.net->dport = dh->dccph_dport;
4343                 break;
4344         }
4345
4346 #if IS_ENABLED(CONFIG_IP_SCTP)
4347         case IPPROTO_SCTP: {
4348                 struct sctphdr _sctph, *sh;
4349
4350                 if (ntohs(ih->frag_off) & IP_OFFSET)
4351                         break;
4352
4353                 offset += ihlen;
4354                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4355                 if (sh == NULL)
4356                         break;
4357
4358                 ad->u.net->sport = sh->source;
4359                 ad->u.net->dport = sh->dest;
4360                 break;
4361         }
4362 #endif
4363         default:
4364                 break;
4365         }
4366 out:
4367         return ret;
4368 }
4369
4370 #if IS_ENABLED(CONFIG_IPV6)
4371
4372 /* Returns error only if unable to parse addresses */
4373 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4374                         struct common_audit_data *ad, u8 *proto)
4375 {
4376         u8 nexthdr;
4377         int ret = -EINVAL, offset;
4378         struct ipv6hdr _ipv6h, *ip6;
4379         __be16 frag_off;
4380
4381         offset = skb_network_offset(skb);
4382         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4383         if (ip6 == NULL)
4384                 goto out;
4385
4386         ad->u.net->v6info.saddr = ip6->saddr;
4387         ad->u.net->v6info.daddr = ip6->daddr;
4388         ret = 0;
4389
4390         nexthdr = ip6->nexthdr;
4391         offset += sizeof(_ipv6h);
4392         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4393         if (offset < 0)
4394                 goto out;
4395
4396         if (proto)
4397                 *proto = nexthdr;
4398
4399         switch (nexthdr) {
4400         case IPPROTO_TCP: {
4401                 struct tcphdr _tcph, *th;
4402
4403                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4404                 if (th == NULL)
4405                         break;
4406
4407                 ad->u.net->sport = th->source;
4408                 ad->u.net->dport = th->dest;
4409                 break;
4410         }
4411
4412         case IPPROTO_UDP: {
4413                 struct udphdr _udph, *uh;
4414
4415                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4416                 if (uh == NULL)
4417                         break;
4418
4419                 ad->u.net->sport = uh->source;
4420                 ad->u.net->dport = uh->dest;
4421                 break;
4422         }
4423
4424         case IPPROTO_DCCP: {
4425                 struct dccp_hdr _dccph, *dh;
4426
4427                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4428                 if (dh == NULL)
4429                         break;
4430
4431                 ad->u.net->sport = dh->dccph_sport;
4432                 ad->u.net->dport = dh->dccph_dport;
4433                 break;
4434         }
4435
4436 #if IS_ENABLED(CONFIG_IP_SCTP)
4437         case IPPROTO_SCTP: {
4438                 struct sctphdr _sctph, *sh;
4439
4440                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4441                 if (sh == NULL)
4442                         break;
4443
4444                 ad->u.net->sport = sh->source;
4445                 ad->u.net->dport = sh->dest;
4446                 break;
4447         }
4448 #endif
4449         /* includes fragments */
4450         default:
4451                 break;
4452         }
4453 out:
4454         return ret;
4455 }
4456
4457 #endif /* IPV6 */
4458
4459 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4460                              char **_addrp, int src, u8 *proto)
4461 {
4462         char *addrp;
4463         int ret;
4464
4465         switch (ad->u.net->family) {
4466         case PF_INET:
4467                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4468                 if (ret)
4469                         goto parse_error;
4470                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4471                                        &ad->u.net->v4info.daddr);
4472                 goto okay;
4473
4474 #if IS_ENABLED(CONFIG_IPV6)
4475         case PF_INET6:
4476                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4477                 if (ret)
4478                         goto parse_error;
4479                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4480                                        &ad->u.net->v6info.daddr);
4481                 goto okay;
4482 #endif  /* IPV6 */
4483         default:
4484                 addrp = NULL;
4485                 goto okay;
4486         }
4487
4488 parse_error:
4489         pr_warn(
4490                "SELinux: failure in selinux_parse_skb(),"
4491                " unable to parse packet\n");
4492         return ret;
4493
4494 okay:
4495         if (_addrp)
4496                 *_addrp = addrp;
4497         return 0;
4498 }
4499
4500 /**
4501  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4502  * @skb: the packet
4503  * @family: protocol family
4504  * @sid: the packet's peer label SID
4505  *
4506  * Description:
4507  * Check the various different forms of network peer labeling and determine
4508  * the peer label/SID for the packet; most of the magic actually occurs in
4509  * the security server function security_net_peersid_cmp().  The function
4510  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4511  * or -EACCES if @sid is invalid due to inconsistencies with the different
4512  * peer labels.
4513  *
4514  */
4515 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4516 {
4517         int err;
4518         u32 xfrm_sid;
4519         u32 nlbl_sid;
4520         u32 nlbl_type;
4521
4522         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4523         if (unlikely(err))
4524                 return -EACCES;
4525         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4526         if (unlikely(err))
4527                 return -EACCES;
4528
4529         err = security_net_peersid_resolve(nlbl_sid,
4530                                            nlbl_type, xfrm_sid, sid);
4531         if (unlikely(err)) {
4532                 pr_warn(
4533                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4534                        " unable to determine packet's peer label\n");
4535                 return -EACCES;
4536         }
4537
4538         return 0;
4539 }
4540
4541 /**
4542  * selinux_conn_sid - Determine the child socket label for a connection
4543  * @sk_sid: the parent socket's SID
4544  * @skb_sid: the packet's SID
4545  * @conn_sid: the resulting connection SID
4546  *
4547  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4548  * combined with the MLS information from @skb_sid in order to create
4549  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4550  * of @sk_sid.  Returns zero on success, negative values on failure.
4551  *
4552  */
4553 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4554 {
4555         int err = 0;
4556
4557         if (skb_sid != SECSID_NULL)
4558                 err = security_sid_mls_copy(sk_sid, skb_sid,
4559                                             conn_sid);
4560         else
4561                 *conn_sid = sk_sid;
4562
4563         return err;
4564 }
4565
4566 /* socket security operations */
4567
4568 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4569                                  u16 secclass, u32 *socksid)
4570 {
4571         if (tsec->sockcreate_sid > SECSID_NULL) {
4572                 *socksid = tsec->sockcreate_sid;
4573                 return 0;
4574         }
4575
4576         return security_transition_sid(tsec->sid, tsec->sid,
4577                                        secclass, NULL, socksid);
4578 }
4579
4580 static int sock_has_perm(struct sock *sk, u32 perms)
4581 {
4582         struct sk_security_struct *sksec = sk->sk_security;
4583         struct common_audit_data ad;
4584         struct lsm_network_audit net;
4585
4586         if (sksec->sid == SECINITSID_KERNEL)
4587                 return 0;
4588
4589         /*
4590          * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4591          * inherited the kernel context from early boot used to be skipped
4592          * here, so preserve that behavior unless the capability is set.
4593          *
4594          * By setting the capability the policy signals that it is ready
4595          * for this quirk to be fixed. Note that sockets created by a kernel
4596          * thread or a usermode helper executed without a transition will
4597          * still be skipped in this check regardless of the policycap
4598          * setting.
4599          */
4600         if (!selinux_policycap_userspace_initial_context() &&
4601             sksec->sid == SECINITSID_INIT)
4602                 return 0;
4603
4604         ad_net_init_from_sk(&ad, &net, sk);
4605
4606         return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4607                             &ad);
4608 }
4609
4610 static int selinux_socket_create(int family, int type,
4611                                  int protocol, int kern)
4612 {
4613         const struct task_security_struct *tsec = selinux_cred(current_cred());
4614         u32 newsid;
4615         u16 secclass;
4616         int rc;
4617
4618         if (kern)
4619                 return 0;
4620
4621         secclass = socket_type_to_security_class(family, type, protocol);
4622         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4623         if (rc)
4624                 return rc;
4625
4626         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4627 }
4628
4629 static int selinux_socket_post_create(struct socket *sock, int family,
4630                                       int type, int protocol, int kern)
4631 {
4632         const struct task_security_struct *tsec = selinux_cred(current_cred());
4633         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4634         struct sk_security_struct *sksec;
4635         u16 sclass = socket_type_to_security_class(family, type, protocol);
4636         u32 sid = SECINITSID_KERNEL;
4637         int err = 0;
4638
4639         if (!kern) {
4640                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4641                 if (err)
4642                         return err;
4643         }
4644
4645         isec->sclass = sclass;
4646         isec->sid = sid;
4647         isec->initialized = LABEL_INITIALIZED;
4648
4649         if (sock->sk) {
4650                 sksec = sock->sk->sk_security;
4651                 sksec->sclass = sclass;
4652                 sksec->sid = sid;
4653                 /* Allows detection of the first association on this socket */
4654                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4655                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4656
4657                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4658         }
4659
4660         return err;
4661 }
4662
4663 static int selinux_socket_socketpair(struct socket *socka,
4664                                      struct socket *sockb)
4665 {
4666         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4667         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4668
4669         sksec_a->peer_sid = sksec_b->sid;
4670         sksec_b->peer_sid = sksec_a->sid;
4671
4672         return 0;
4673 }
4674
4675 /* Range of port numbers used to automatically bind.
4676    Need to determine whether we should perform a name_bind
4677    permission check between the socket and the port number. */
4678
4679 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4680 {
4681         struct sock *sk = sock->sk;
4682         struct sk_security_struct *sksec = sk->sk_security;
4683         u16 family;
4684         int err;
4685
4686         err = sock_has_perm(sk, SOCKET__BIND);
4687         if (err)
4688                 goto out;
4689
4690         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4691         family = sk->sk_family;
4692         if (family == PF_INET || family == PF_INET6) {
4693                 char *addrp;
4694                 struct common_audit_data ad;
4695                 struct lsm_network_audit net = {0,};
4696                 struct sockaddr_in *addr4 = NULL;
4697                 struct sockaddr_in6 *addr6 = NULL;
4698                 u16 family_sa;
4699                 unsigned short snum;
4700                 u32 sid, node_perm;
4701
4702                 /*
4703                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4704                  * that validates multiple binding addresses. Because of this
4705                  * need to check address->sa_family as it is possible to have
4706                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4707                  */
4708                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4709                         return -EINVAL;
4710                 family_sa = address->sa_family;
4711                 switch (family_sa) {
4712                 case AF_UNSPEC:
4713                 case AF_INET:
4714                         if (addrlen < sizeof(struct sockaddr_in))
4715                                 return -EINVAL;
4716                         addr4 = (struct sockaddr_in *)address;
4717                         if (family_sa == AF_UNSPEC) {
4718                                 if (family == PF_INET6) {
4719                                         /* Length check from inet6_bind_sk() */
4720                                         if (addrlen < SIN6_LEN_RFC2133)
4721                                                 return -EINVAL;
4722                                         /* Family check from __inet6_bind() */
4723                                         goto err_af;
4724                                 }
4725                                 /* see __inet_bind(), we only want to allow
4726                                  * AF_UNSPEC if the address is INADDR_ANY
4727                                  */
4728                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4729                                         goto err_af;
4730                                 family_sa = AF_INET;
4731                         }
4732                         snum = ntohs(addr4->sin_port);
4733                         addrp = (char *)&addr4->sin_addr.s_addr;
4734                         break;
4735                 case AF_INET6:
4736                         if (addrlen < SIN6_LEN_RFC2133)
4737                                 return -EINVAL;
4738                         addr6 = (struct sockaddr_in6 *)address;
4739                         snum = ntohs(addr6->sin6_port);
4740                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4741                         break;
4742                 default:
4743                         goto err_af;
4744                 }
4745
4746                 ad.type = LSM_AUDIT_DATA_NET;
4747                 ad.u.net = &net;
4748                 ad.u.net->sport = htons(snum);
4749                 ad.u.net->family = family_sa;
4750
4751                 if (snum) {
4752                         int low, high;
4753
4754                         inet_get_local_port_range(sock_net(sk), &low, &high);
4755
4756                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4757                             snum < low || snum > high) {
4758                                 err = sel_netport_sid(sk->sk_protocol,
4759                                                       snum, &sid);
4760                                 if (err)
4761                                         goto out;
4762                                 err = avc_has_perm(sksec->sid, sid,
4763                                                    sksec->sclass,
4764                                                    SOCKET__NAME_BIND, &ad);
4765                                 if (err)
4766                                         goto out;
4767                         }
4768                 }
4769
4770                 switch (sksec->sclass) {
4771                 case SECCLASS_TCP_SOCKET:
4772                         node_perm = TCP_SOCKET__NODE_BIND;
4773                         break;
4774
4775                 case SECCLASS_UDP_SOCKET:
4776                         node_perm = UDP_SOCKET__NODE_BIND;
4777                         break;
4778
4779                 case SECCLASS_DCCP_SOCKET:
4780                         node_perm = DCCP_SOCKET__NODE_BIND;
4781                         break;
4782
4783                 case SECCLASS_SCTP_SOCKET:
4784                         node_perm = SCTP_SOCKET__NODE_BIND;
4785                         break;
4786
4787                 default:
4788                         node_perm = RAWIP_SOCKET__NODE_BIND;
4789                         break;
4790                 }
4791
4792                 err = sel_netnode_sid(addrp, family_sa, &sid);
4793                 if (err)
4794                         goto out;
4795
4796                 if (family_sa == AF_INET)
4797                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4798                 else
4799                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4800
4801                 err = avc_has_perm(sksec->sid, sid,
4802                                    sksec->sclass, node_perm, &ad);
4803                 if (err)
4804                         goto out;
4805         }
4806 out:
4807         return err;
4808 err_af:
4809         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4810         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4811                 return -EINVAL;
4812         return -EAFNOSUPPORT;
4813 }
4814
4815 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4816  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4817  */
4818 static int selinux_socket_connect_helper(struct socket *sock,
4819                                          struct sockaddr *address, int addrlen)
4820 {
4821         struct sock *sk = sock->sk;
4822         struct sk_security_struct *sksec = sk->sk_security;
4823         int err;
4824
4825         err = sock_has_perm(sk, SOCKET__CONNECT);
4826         if (err)
4827                 return err;
4828         if (addrlen < offsetofend(struct sockaddr, sa_family))
4829                 return -EINVAL;
4830
4831         /* connect(AF_UNSPEC) has special handling, as it is a documented
4832          * way to disconnect the socket
4833          */
4834         if (address->sa_family == AF_UNSPEC)
4835                 return 0;
4836
4837         /*
4838          * If a TCP, DCCP or SCTP socket, check name_connect permission
4839          * for the port.
4840          */
4841         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4842             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4843             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4844                 struct common_audit_data ad;
4845                 struct lsm_network_audit net = {0,};
4846                 struct sockaddr_in *addr4 = NULL;
4847                 struct sockaddr_in6 *addr6 = NULL;
4848                 unsigned short snum;
4849                 u32 sid, perm;
4850
4851                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4852                  * that validates multiple connect addresses. Because of this
4853                  * need to check address->sa_family as it is possible to have
4854                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4855                  */
4856                 switch (address->sa_family) {
4857                 case AF_INET:
4858                         addr4 = (struct sockaddr_in *)address;
4859                         if (addrlen < sizeof(struct sockaddr_in))
4860                                 return -EINVAL;
4861                         snum = ntohs(addr4->sin_port);
4862                         break;
4863                 case AF_INET6:
4864                         addr6 = (struct sockaddr_in6 *)address;
4865                         if (addrlen < SIN6_LEN_RFC2133)
4866                                 return -EINVAL;
4867                         snum = ntohs(addr6->sin6_port);
4868                         break;
4869                 default:
4870                         /* Note that SCTP services expect -EINVAL, whereas
4871                          * others expect -EAFNOSUPPORT.
4872                          */
4873                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4874                                 return -EINVAL;
4875                         else
4876                                 return -EAFNOSUPPORT;
4877                 }
4878
4879                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4880                 if (err)
4881                         return err;
4882
4883                 switch (sksec->sclass) {
4884                 case SECCLASS_TCP_SOCKET:
4885                         perm = TCP_SOCKET__NAME_CONNECT;
4886                         break;
4887                 case SECCLASS_DCCP_SOCKET:
4888                         perm = DCCP_SOCKET__NAME_CONNECT;
4889                         break;
4890                 case SECCLASS_SCTP_SOCKET:
4891                         perm = SCTP_SOCKET__NAME_CONNECT;
4892                         break;
4893                 }
4894
4895                 ad.type = LSM_AUDIT_DATA_NET;
4896                 ad.u.net = &net;
4897                 ad.u.net->dport = htons(snum);
4898                 ad.u.net->family = address->sa_family;
4899                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4900                 if (err)
4901                         return err;
4902         }
4903
4904         return 0;
4905 }
4906
4907 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4908 static int selinux_socket_connect(struct socket *sock,
4909                                   struct sockaddr *address, int addrlen)
4910 {
4911         int err;
4912         struct sock *sk = sock->sk;
4913
4914         err = selinux_socket_connect_helper(sock, address, addrlen);
4915         if (err)
4916                 return err;
4917
4918         return selinux_netlbl_socket_connect(sk, address);
4919 }
4920
4921 static int selinux_socket_listen(struct socket *sock, int backlog)
4922 {
4923         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4924 }
4925
4926 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4927 {
4928         int err;
4929         struct inode_security_struct *isec;
4930         struct inode_security_struct *newisec;
4931         u16 sclass;
4932         u32 sid;
4933
4934         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4935         if (err)
4936                 return err;
4937
4938         isec = inode_security_novalidate(SOCK_INODE(sock));
4939         spin_lock(&isec->lock);
4940         sclass = isec->sclass;
4941         sid = isec->sid;
4942         spin_unlock(&isec->lock);
4943
4944         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4945         newisec->sclass = sclass;
4946         newisec->sid = sid;
4947         newisec->initialized = LABEL_INITIALIZED;
4948
4949         return 0;
4950 }
4951
4952 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4953                                   int size)
4954 {
4955         return sock_has_perm(sock->sk, SOCKET__WRITE);
4956 }
4957
4958 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4959                                   int size, int flags)
4960 {
4961         return sock_has_perm(sock->sk, SOCKET__READ);
4962 }
4963
4964 static int selinux_socket_getsockname(struct socket *sock)
4965 {
4966         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4967 }
4968
4969 static int selinux_socket_getpeername(struct socket *sock)
4970 {
4971         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4972 }
4973
4974 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4975 {
4976         int err;
4977
4978         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4979         if (err)
4980                 return err;
4981
4982         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4983 }
4984
4985 static int selinux_socket_getsockopt(struct socket *sock, int level,
4986                                      int optname)
4987 {
4988         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4989 }
4990
4991 static int selinux_socket_shutdown(struct socket *sock, int how)
4992 {
4993         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4994 }
4995
4996 static int selinux_socket_unix_stream_connect(struct sock *sock,
4997                                               struct sock *other,
4998                                               struct sock *newsk)
4999 {
5000         struct sk_security_struct *sksec_sock = sock->sk_security;
5001         struct sk_security_struct *sksec_other = other->sk_security;
5002         struct sk_security_struct *sksec_new = newsk->sk_security;
5003         struct common_audit_data ad;
5004         struct lsm_network_audit net;
5005         int err;
5006
5007         ad_net_init_from_sk(&ad, &net, other);
5008
5009         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5010                            sksec_other->sclass,
5011                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5012         if (err)
5013                 return err;
5014
5015         /* server child socket */
5016         sksec_new->peer_sid = sksec_sock->sid;
5017         err = security_sid_mls_copy(sksec_other->sid,
5018                                     sksec_sock->sid, &sksec_new->sid);
5019         if (err)
5020                 return err;
5021
5022         /* connecting socket */
5023         sksec_sock->peer_sid = sksec_new->sid;
5024
5025         return 0;
5026 }
5027
5028 static int selinux_socket_unix_may_send(struct socket *sock,
5029                                         struct socket *other)
5030 {
5031         struct sk_security_struct *ssec = sock->sk->sk_security;
5032         struct sk_security_struct *osec = other->sk->sk_security;
5033         struct common_audit_data ad;
5034         struct lsm_network_audit net;
5035
5036         ad_net_init_from_sk(&ad, &net, other->sk);
5037
5038         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5039                             &ad);
5040 }
5041
5042 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5043                                     char *addrp, u16 family, u32 peer_sid,
5044                                     struct common_audit_data *ad)
5045 {
5046         int err;
5047         u32 if_sid;
5048         u32 node_sid;
5049
5050         err = sel_netif_sid(ns, ifindex, &if_sid);
5051         if (err)
5052                 return err;
5053         err = avc_has_perm(peer_sid, if_sid,
5054                            SECCLASS_NETIF, NETIF__INGRESS, ad);
5055         if (err)
5056                 return err;
5057
5058         err = sel_netnode_sid(addrp, family, &node_sid);
5059         if (err)
5060                 return err;
5061         return avc_has_perm(peer_sid, node_sid,
5062                             SECCLASS_NODE, NODE__RECVFROM, ad);
5063 }
5064
5065 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5066                                        u16 family)
5067 {
5068         int err = 0;
5069         struct sk_security_struct *sksec = sk->sk_security;
5070         u32 sk_sid = sksec->sid;
5071         struct common_audit_data ad;
5072         struct lsm_network_audit net;
5073         char *addrp;
5074
5075         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5076         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5077         if (err)
5078                 return err;
5079
5080         if (selinux_secmark_enabled()) {
5081                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5082                                    PACKET__RECV, &ad);
5083                 if (err)
5084                         return err;
5085         }
5086
5087         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5088         if (err)
5089                 return err;
5090         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5091
5092         return err;
5093 }
5094
5095 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5096 {
5097         int err, peerlbl_active, secmark_active;
5098         struct sk_security_struct *sksec = sk->sk_security;
5099         u16 family = sk->sk_family;
5100         u32 sk_sid = sksec->sid;
5101         struct common_audit_data ad;
5102         struct lsm_network_audit net;
5103         char *addrp;
5104
5105         if (family != PF_INET && family != PF_INET6)
5106                 return 0;
5107
5108         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5109         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5110                 family = PF_INET;
5111
5112         /* If any sort of compatibility mode is enabled then handoff processing
5113          * to the selinux_sock_rcv_skb_compat() function to deal with the
5114          * special handling.  We do this in an attempt to keep this function
5115          * as fast and as clean as possible. */
5116         if (!selinux_policycap_netpeer())
5117                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5118
5119         secmark_active = selinux_secmark_enabled();
5120         peerlbl_active = selinux_peerlbl_enabled();
5121         if (!secmark_active && !peerlbl_active)
5122                 return 0;
5123
5124         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5125         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5126         if (err)
5127                 return err;
5128
5129         if (peerlbl_active) {
5130                 u32 peer_sid;
5131
5132                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5133                 if (err)
5134                         return err;
5135                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5136                                                addrp, family, peer_sid, &ad);
5137                 if (err) {
5138                         selinux_netlbl_err(skb, family, err, 0);
5139                         return err;
5140                 }
5141                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5142                                    PEER__RECV, &ad);
5143                 if (err) {
5144                         selinux_netlbl_err(skb, family, err, 0);
5145                         return err;
5146                 }
5147         }
5148
5149         if (secmark_active) {
5150                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5151                                    PACKET__RECV, &ad);
5152                 if (err)
5153                         return err;
5154         }
5155
5156         return err;
5157 }
5158
5159 static int selinux_socket_getpeersec_stream(struct socket *sock,
5160                                             sockptr_t optval, sockptr_t optlen,
5161                                             unsigned int len)
5162 {
5163         int err = 0;
5164         char *scontext = NULL;
5165         u32 scontext_len;
5166         struct sk_security_struct *sksec = sock->sk->sk_security;
5167         u32 peer_sid = SECSID_NULL;
5168
5169         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5170             sksec->sclass == SECCLASS_TCP_SOCKET ||
5171             sksec->sclass == SECCLASS_SCTP_SOCKET)
5172                 peer_sid = sksec->peer_sid;
5173         if (peer_sid == SECSID_NULL)
5174                 return -ENOPROTOOPT;
5175
5176         err = security_sid_to_context(peer_sid, &scontext,
5177                                       &scontext_len);
5178         if (err)
5179                 return err;
5180         if (scontext_len > len) {
5181                 err = -ERANGE;
5182                 goto out_len;
5183         }
5184
5185         if (copy_to_sockptr(optval, scontext, scontext_len))
5186                 err = -EFAULT;
5187 out_len:
5188         if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5189                 err = -EFAULT;
5190         kfree(scontext);
5191         return err;
5192 }
5193
5194 static int selinux_socket_getpeersec_dgram(struct socket *sock,
5195                                            struct sk_buff *skb, u32 *secid)
5196 {
5197         u32 peer_secid = SECSID_NULL;
5198         u16 family;
5199
5200         if (skb && skb->protocol == htons(ETH_P_IP))
5201                 family = PF_INET;
5202         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5203                 family = PF_INET6;
5204         else if (sock)
5205                 family = sock->sk->sk_family;
5206         else {
5207                 *secid = SECSID_NULL;
5208                 return -EINVAL;
5209         }
5210
5211         if (sock && family == PF_UNIX) {
5212                 struct inode_security_struct *isec;
5213                 isec = inode_security_novalidate(SOCK_INODE(sock));
5214                 peer_secid = isec->sid;
5215         } else if (skb)
5216                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5217
5218         *secid = peer_secid;
5219         if (peer_secid == SECSID_NULL)
5220                 return -ENOPROTOOPT;
5221         return 0;
5222 }
5223
5224 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5225 {
5226         struct sk_security_struct *sksec;
5227
5228         sksec = kzalloc(sizeof(*sksec), priority);
5229         if (!sksec)
5230                 return -ENOMEM;
5231
5232         sksec->peer_sid = SECINITSID_UNLABELED;
5233         sksec->sid = SECINITSID_UNLABELED;
5234         sksec->sclass = SECCLASS_SOCKET;
5235         selinux_netlbl_sk_security_reset(sksec);
5236         sk->sk_security = sksec;
5237
5238         return 0;
5239 }
5240
5241 static void selinux_sk_free_security(struct sock *sk)
5242 {
5243         struct sk_security_struct *sksec = sk->sk_security;
5244
5245         sk->sk_security = NULL;
5246         selinux_netlbl_sk_security_free(sksec);
5247         kfree(sksec);
5248 }
5249
5250 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5251 {
5252         struct sk_security_struct *sksec = sk->sk_security;
5253         struct sk_security_struct *newsksec = newsk->sk_security;
5254
5255         newsksec->sid = sksec->sid;
5256         newsksec->peer_sid = sksec->peer_sid;
5257         newsksec->sclass = sksec->sclass;
5258
5259         selinux_netlbl_sk_security_reset(newsksec);
5260 }
5261
5262 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5263 {
5264         if (!sk)
5265                 *secid = SECINITSID_ANY_SOCKET;
5266         else {
5267                 const struct sk_security_struct *sksec = sk->sk_security;
5268
5269                 *secid = sksec->sid;
5270         }
5271 }
5272
5273 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5274 {
5275         struct inode_security_struct *isec =
5276                 inode_security_novalidate(SOCK_INODE(parent));
5277         struct sk_security_struct *sksec = sk->sk_security;
5278
5279         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5280             sk->sk_family == PF_UNIX)
5281                 isec->sid = sksec->sid;
5282         sksec->sclass = isec->sclass;
5283 }
5284
5285 /*
5286  * Determines peer_secid for the asoc and updates socket's peer label
5287  * if it's the first association on the socket.
5288  */
5289 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5290                                           struct sk_buff *skb)
5291 {
5292         struct sock *sk = asoc->base.sk;
5293         u16 family = sk->sk_family;
5294         struct sk_security_struct *sksec = sk->sk_security;
5295         struct common_audit_data ad;
5296         struct lsm_network_audit net;
5297         int err;
5298
5299         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5300         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5301                 family = PF_INET;
5302
5303         if (selinux_peerlbl_enabled()) {
5304                 asoc->peer_secid = SECSID_NULL;
5305
5306                 /* This will return peer_sid = SECSID_NULL if there are
5307                  * no peer labels, see security_net_peersid_resolve().
5308                  */
5309                 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5310                 if (err)
5311                         return err;
5312
5313                 if (asoc->peer_secid == SECSID_NULL)
5314                         asoc->peer_secid = SECINITSID_UNLABELED;
5315         } else {
5316                 asoc->peer_secid = SECINITSID_UNLABELED;
5317         }
5318
5319         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5320                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5321
5322                 /* Here as first association on socket. As the peer SID
5323                  * was allowed by peer recv (and the netif/node checks),
5324                  * then it is approved by policy and used as the primary
5325                  * peer SID for getpeercon(3).
5326                  */
5327                 sksec->peer_sid = asoc->peer_secid;
5328         } else if (sksec->peer_sid != asoc->peer_secid) {
5329                 /* Other association peer SIDs are checked to enforce
5330                  * consistency among the peer SIDs.
5331                  */
5332                 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5333                 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5334                                    sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5335                                    &ad);
5336                 if (err)
5337                         return err;
5338         }
5339         return 0;
5340 }
5341
5342 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5343  * happens on an incoming connect(2), sctp_connectx(3) or
5344  * sctp_sendmsg(3) (with no association already present).
5345  */
5346 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5347                                       struct sk_buff *skb)
5348 {
5349         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5350         u32 conn_sid;
5351         int err;
5352
5353         if (!selinux_policycap_extsockclass())
5354                 return 0;
5355
5356         err = selinux_sctp_process_new_assoc(asoc, skb);
5357         if (err)
5358                 return err;
5359
5360         /* Compute the MLS component for the connection and store
5361          * the information in asoc. This will be used by SCTP TCP type
5362          * sockets and peeled off connections as they cause a new
5363          * socket to be generated. selinux_sctp_sk_clone() will then
5364          * plug this into the new socket.
5365          */
5366         err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5367         if (err)
5368                 return err;
5369
5370         asoc->secid = conn_sid;
5371
5372         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5373         return selinux_netlbl_sctp_assoc_request(asoc, skb);
5374 }
5375
5376 /* Called when SCTP receives a COOKIE ACK chunk as the final
5377  * response to an association request (initited by us).
5378  */
5379 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5380                                           struct sk_buff *skb)
5381 {
5382         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5383
5384         if (!selinux_policycap_extsockclass())
5385                 return 0;
5386
5387         /* Inherit secid from the parent socket - this will be picked up
5388          * by selinux_sctp_sk_clone() if the association gets peeled off
5389          * into a new socket.
5390          */
5391         asoc->secid = sksec->sid;
5392
5393         return selinux_sctp_process_new_assoc(asoc, skb);
5394 }
5395
5396 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5397  * based on their @optname.
5398  */
5399 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5400                                      struct sockaddr *address,
5401                                      int addrlen)
5402 {
5403         int len, err = 0, walk_size = 0;
5404         void *addr_buf;
5405         struct sockaddr *addr;
5406         struct socket *sock;
5407
5408         if (!selinux_policycap_extsockclass())
5409                 return 0;
5410
5411         /* Process one or more addresses that may be IPv4 or IPv6 */
5412         sock = sk->sk_socket;
5413         addr_buf = address;
5414
5415         while (walk_size < addrlen) {
5416                 if (walk_size + sizeof(sa_family_t) > addrlen)
5417                         return -EINVAL;
5418
5419                 addr = addr_buf;
5420                 switch (addr->sa_family) {
5421                 case AF_UNSPEC:
5422                 case AF_INET:
5423                         len = sizeof(struct sockaddr_in);
5424                         break;
5425                 case AF_INET6:
5426                         len = sizeof(struct sockaddr_in6);
5427                         break;
5428                 default:
5429                         return -EINVAL;
5430                 }
5431
5432                 if (walk_size + len > addrlen)
5433                         return -EINVAL;
5434
5435                 err = -EINVAL;
5436                 switch (optname) {
5437                 /* Bind checks */
5438                 case SCTP_PRIMARY_ADDR:
5439                 case SCTP_SET_PEER_PRIMARY_ADDR:
5440                 case SCTP_SOCKOPT_BINDX_ADD:
5441                         err = selinux_socket_bind(sock, addr, len);
5442                         break;
5443                 /* Connect checks */
5444                 case SCTP_SOCKOPT_CONNECTX:
5445                 case SCTP_PARAM_SET_PRIMARY:
5446                 case SCTP_PARAM_ADD_IP:
5447                 case SCTP_SENDMSG_CONNECT:
5448                         err = selinux_socket_connect_helper(sock, addr, len);
5449                         if (err)
5450                                 return err;
5451
5452                         /* As selinux_sctp_bind_connect() is called by the
5453                          * SCTP protocol layer, the socket is already locked,
5454                          * therefore selinux_netlbl_socket_connect_locked()
5455                          * is called here. The situations handled are:
5456                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5457                          * whenever a new IP address is added or when a new
5458                          * primary address is selected.
5459                          * Note that an SCTP connect(2) call happens before
5460                          * the SCTP protocol layer and is handled via
5461                          * selinux_socket_connect().
5462                          */
5463                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5464                         break;
5465                 }
5466
5467                 if (err)
5468                         return err;
5469
5470                 addr_buf += len;
5471                 walk_size += len;
5472         }
5473
5474         return 0;
5475 }
5476
5477 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5478 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5479                                   struct sock *newsk)
5480 {
5481         struct sk_security_struct *sksec = sk->sk_security;
5482         struct sk_security_struct *newsksec = newsk->sk_security;
5483
5484         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5485          * the non-sctp clone version.
5486          */
5487         if (!selinux_policycap_extsockclass())
5488                 return selinux_sk_clone_security(sk, newsk);
5489
5490         newsksec->sid = asoc->secid;
5491         newsksec->peer_sid = asoc->peer_secid;
5492         newsksec->sclass = sksec->sclass;
5493         selinux_netlbl_sctp_sk_clone(sk, newsk);
5494 }
5495
5496 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5497 {
5498         struct sk_security_struct *ssksec = ssk->sk_security;
5499         struct sk_security_struct *sksec = sk->sk_security;
5500
5501         ssksec->sclass = sksec->sclass;
5502         ssksec->sid = sksec->sid;
5503
5504         /* replace the existing subflow label deleting the existing one
5505          * and re-recreating a new label using the updated context
5506          */
5507         selinux_netlbl_sk_security_free(ssksec);
5508         return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5509 }
5510
5511 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5512                                      struct request_sock *req)
5513 {
5514         struct sk_security_struct *sksec = sk->sk_security;
5515         int err;
5516         u16 family = req->rsk_ops->family;
5517         u32 connsid;
5518         u32 peersid;
5519
5520         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5521         if (err)
5522                 return err;
5523         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5524         if (err)
5525                 return err;
5526         req->secid = connsid;
5527         req->peer_secid = peersid;
5528
5529         return selinux_netlbl_inet_conn_request(req, family);
5530 }
5531
5532 static void selinux_inet_csk_clone(struct sock *newsk,
5533                                    const struct request_sock *req)
5534 {
5535         struct sk_security_struct *newsksec = newsk->sk_security;
5536
5537         newsksec->sid = req->secid;
5538         newsksec->peer_sid = req->peer_secid;
5539         /* NOTE: Ideally, we should also get the isec->sid for the
5540            new socket in sync, but we don't have the isec available yet.
5541            So we will wait until sock_graft to do it, by which
5542            time it will have been created and available. */
5543
5544         /* We don't need to take any sort of lock here as we are the only
5545          * thread with access to newsksec */
5546         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5547 }
5548
5549 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5550 {
5551         u16 family = sk->sk_family;
5552         struct sk_security_struct *sksec = sk->sk_security;
5553
5554         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5555         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5556                 family = PF_INET;
5557
5558         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5559 }
5560
5561 static int selinux_secmark_relabel_packet(u32 sid)
5562 {
5563         return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5564                             NULL);
5565 }
5566
5567 static void selinux_secmark_refcount_inc(void)
5568 {
5569         atomic_inc(&selinux_secmark_refcount);
5570 }
5571
5572 static void selinux_secmark_refcount_dec(void)
5573 {
5574         atomic_dec(&selinux_secmark_refcount);
5575 }
5576
5577 static void selinux_req_classify_flow(const struct request_sock *req,
5578                                       struct flowi_common *flic)
5579 {
5580         flic->flowic_secid = req->secid;
5581 }
5582
5583 static int selinux_tun_dev_alloc_security(void **security)
5584 {
5585         struct tun_security_struct *tunsec;
5586
5587         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5588         if (!tunsec)
5589                 return -ENOMEM;
5590         tunsec->sid = current_sid();
5591
5592         *security = tunsec;
5593         return 0;
5594 }
5595
5596 static void selinux_tun_dev_free_security(void *security)
5597 {
5598         kfree(security);
5599 }
5600
5601 static int selinux_tun_dev_create(void)
5602 {
5603         u32 sid = current_sid();
5604
5605         /* we aren't taking into account the "sockcreate" SID since the socket
5606          * that is being created here is not a socket in the traditional sense,
5607          * instead it is a private sock, accessible only to the kernel, and
5608          * representing a wide range of network traffic spanning multiple
5609          * connections unlike traditional sockets - check the TUN driver to
5610          * get a better understanding of why this socket is special */
5611
5612         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5613                             NULL);
5614 }
5615
5616 static int selinux_tun_dev_attach_queue(void *security)
5617 {
5618         struct tun_security_struct *tunsec = security;
5619
5620         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5621                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5622 }
5623
5624 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5625 {
5626         struct tun_security_struct *tunsec = security;
5627         struct sk_security_struct *sksec = sk->sk_security;
5628
5629         /* we don't currently perform any NetLabel based labeling here and it
5630          * isn't clear that we would want to do so anyway; while we could apply
5631          * labeling without the support of the TUN user the resulting labeled
5632          * traffic from the other end of the connection would almost certainly
5633          * cause confusion to the TUN user that had no idea network labeling
5634          * protocols were being used */
5635
5636         sksec->sid = tunsec->sid;
5637         sksec->sclass = SECCLASS_TUN_SOCKET;
5638
5639         return 0;
5640 }
5641
5642 static int selinux_tun_dev_open(void *security)
5643 {
5644         struct tun_security_struct *tunsec = security;
5645         u32 sid = current_sid();
5646         int err;
5647
5648         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5649                            TUN_SOCKET__RELABELFROM, NULL);
5650         if (err)
5651                 return err;
5652         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5653                            TUN_SOCKET__RELABELTO, NULL);
5654         if (err)
5655                 return err;
5656         tunsec->sid = sid;
5657
5658         return 0;
5659 }
5660
5661 #ifdef CONFIG_NETFILTER
5662
5663 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5664                                        const struct nf_hook_state *state)
5665 {
5666         int ifindex;
5667         u16 family;
5668         char *addrp;
5669         u32 peer_sid;
5670         struct common_audit_data ad;
5671         struct lsm_network_audit net;
5672         int secmark_active, peerlbl_active;
5673
5674         if (!selinux_policycap_netpeer())
5675                 return NF_ACCEPT;
5676
5677         secmark_active = selinux_secmark_enabled();
5678         peerlbl_active = selinux_peerlbl_enabled();
5679         if (!secmark_active && !peerlbl_active)
5680                 return NF_ACCEPT;
5681
5682         family = state->pf;
5683         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5684                 return NF_DROP;
5685
5686         ifindex = state->in->ifindex;
5687         ad_net_init_from_iif(&ad, &net, ifindex, family);
5688         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5689                 return NF_DROP;
5690
5691         if (peerlbl_active) {
5692                 int err;
5693
5694                 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5695                                                addrp, family, peer_sid, &ad);
5696                 if (err) {
5697                         selinux_netlbl_err(skb, family, err, 1);
5698                         return NF_DROP;
5699                 }
5700         }
5701
5702         if (secmark_active)
5703                 if (avc_has_perm(peer_sid, skb->secmark,
5704                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5705                         return NF_DROP;
5706
5707         if (netlbl_enabled())
5708                 /* we do this in the FORWARD path and not the POST_ROUTING
5709                  * path because we want to make sure we apply the necessary
5710                  * labeling before IPsec is applied so we can leverage AH
5711                  * protection */
5712                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5713                         return NF_DROP;
5714
5715         return NF_ACCEPT;
5716 }
5717
5718 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5719                                       const struct nf_hook_state *state)
5720 {
5721         struct sock *sk;
5722         u32 sid;
5723
5724         if (!netlbl_enabled())
5725                 return NF_ACCEPT;
5726
5727         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5728          * because we want to make sure we apply the necessary labeling
5729          * before IPsec is applied so we can leverage AH protection */
5730         sk = skb->sk;
5731         if (sk) {
5732                 struct sk_security_struct *sksec;
5733
5734                 if (sk_listener(sk))
5735                         /* if the socket is the listening state then this
5736                          * packet is a SYN-ACK packet which means it needs to
5737                          * be labeled based on the connection/request_sock and
5738                          * not the parent socket.  unfortunately, we can't
5739                          * lookup the request_sock yet as it isn't queued on
5740                          * the parent socket until after the SYN-ACK is sent.
5741                          * the "solution" is to simply pass the packet as-is
5742                          * as any IP option based labeling should be copied
5743                          * from the initial connection request (in the IP
5744                          * layer).  it is far from ideal, but until we get a
5745                          * security label in the packet itself this is the
5746                          * best we can do. */
5747                         return NF_ACCEPT;
5748
5749                 /* standard practice, label using the parent socket */
5750                 sksec = sk->sk_security;
5751                 sid = sksec->sid;
5752         } else
5753                 sid = SECINITSID_KERNEL;
5754         if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5755                 return NF_DROP;
5756
5757         return NF_ACCEPT;
5758 }
5759
5760
5761 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5762                                         const struct nf_hook_state *state)
5763 {
5764         struct sock *sk;
5765         struct sk_security_struct *sksec;
5766         struct common_audit_data ad;
5767         struct lsm_network_audit net;
5768         u8 proto = 0;
5769
5770         sk = skb_to_full_sk(skb);
5771         if (sk == NULL)
5772                 return NF_ACCEPT;
5773         sksec = sk->sk_security;
5774
5775         ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5776         if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5777                 return NF_DROP;
5778
5779         if (selinux_secmark_enabled())
5780                 if (avc_has_perm(sksec->sid, skb->secmark,
5781                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5782                         return NF_DROP_ERR(-ECONNREFUSED);
5783
5784         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5785                 return NF_DROP_ERR(-ECONNREFUSED);
5786
5787         return NF_ACCEPT;
5788 }
5789
5790 static unsigned int selinux_ip_postroute(void *priv,
5791                                          struct sk_buff *skb,
5792                                          const struct nf_hook_state *state)
5793 {
5794         u16 family;
5795         u32 secmark_perm;
5796         u32 peer_sid;
5797         int ifindex;
5798         struct sock *sk;
5799         struct common_audit_data ad;
5800         struct lsm_network_audit net;
5801         char *addrp;
5802         int secmark_active, peerlbl_active;
5803
5804         /* If any sort of compatibility mode is enabled then handoff processing
5805          * to the selinux_ip_postroute_compat() function to deal with the
5806          * special handling.  We do this in an attempt to keep this function
5807          * as fast and as clean as possible. */
5808         if (!selinux_policycap_netpeer())
5809                 return selinux_ip_postroute_compat(skb, state);
5810
5811         secmark_active = selinux_secmark_enabled();
5812         peerlbl_active = selinux_peerlbl_enabled();
5813         if (!secmark_active && !peerlbl_active)
5814                 return NF_ACCEPT;
5815
5816         sk = skb_to_full_sk(skb);
5817
5818 #ifdef CONFIG_XFRM
5819         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5820          * packet transformation so allow the packet to pass without any checks
5821          * since we'll have another chance to perform access control checks
5822          * when the packet is on it's final way out.
5823          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5824          *       is NULL, in this case go ahead and apply access control.
5825          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5826          *       TCP listening state we cannot wait until the XFRM processing
5827          *       is done as we will miss out on the SA label if we do;
5828          *       unfortunately, this means more work, but it is only once per
5829          *       connection. */
5830         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5831             !(sk && sk_listener(sk)))
5832                 return NF_ACCEPT;
5833 #endif
5834
5835         family = state->pf;
5836         if (sk == NULL) {
5837                 /* Without an associated socket the packet is either coming
5838                  * from the kernel or it is being forwarded; check the packet
5839                  * to determine which and if the packet is being forwarded
5840                  * query the packet directly to determine the security label. */
5841                 if (skb->skb_iif) {
5842                         secmark_perm = PACKET__FORWARD_OUT;
5843                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5844                                 return NF_DROP;
5845                 } else {
5846                         secmark_perm = PACKET__SEND;
5847                         peer_sid = SECINITSID_KERNEL;
5848                 }
5849         } else if (sk_listener(sk)) {
5850                 /* Locally generated packet but the associated socket is in the
5851                  * listening state which means this is a SYN-ACK packet.  In
5852                  * this particular case the correct security label is assigned
5853                  * to the connection/request_sock but unfortunately we can't
5854                  * query the request_sock as it isn't queued on the parent
5855                  * socket until after the SYN-ACK packet is sent; the only
5856                  * viable choice is to regenerate the label like we do in
5857                  * selinux_inet_conn_request().  See also selinux_ip_output()
5858                  * for similar problems. */
5859                 u32 skb_sid;
5860                 struct sk_security_struct *sksec;
5861
5862                 sksec = sk->sk_security;
5863                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5864                         return NF_DROP;
5865                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5866                  * and the packet has been through at least one XFRM
5867                  * transformation then we must be dealing with the "final"
5868                  * form of labeled IPsec packet; since we've already applied
5869                  * all of our access controls on this packet we can safely
5870                  * pass the packet. */
5871                 if (skb_sid == SECSID_NULL) {
5872                         switch (family) {
5873                         case PF_INET:
5874                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5875                                         return NF_ACCEPT;
5876                                 break;
5877                         case PF_INET6:
5878                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5879                                         return NF_ACCEPT;
5880                                 break;
5881                         default:
5882                                 return NF_DROP_ERR(-ECONNREFUSED);
5883                         }
5884                 }
5885                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5886                         return NF_DROP;
5887                 secmark_perm = PACKET__SEND;
5888         } else {
5889                 /* Locally generated packet, fetch the security label from the
5890                  * associated socket. */
5891                 struct sk_security_struct *sksec = sk->sk_security;
5892                 peer_sid = sksec->sid;
5893                 secmark_perm = PACKET__SEND;
5894         }
5895
5896         ifindex = state->out->ifindex;
5897         ad_net_init_from_iif(&ad, &net, ifindex, family);
5898         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5899                 return NF_DROP;
5900
5901         if (secmark_active)
5902                 if (avc_has_perm(peer_sid, skb->secmark,
5903                                  SECCLASS_PACKET, secmark_perm, &ad))
5904                         return NF_DROP_ERR(-ECONNREFUSED);
5905
5906         if (peerlbl_active) {
5907                 u32 if_sid;
5908                 u32 node_sid;
5909
5910                 if (sel_netif_sid(state->net, ifindex, &if_sid))
5911                         return NF_DROP;
5912                 if (avc_has_perm(peer_sid, if_sid,
5913                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5914                         return NF_DROP_ERR(-ECONNREFUSED);
5915
5916                 if (sel_netnode_sid(addrp, family, &node_sid))
5917                         return NF_DROP;
5918                 if (avc_has_perm(peer_sid, node_sid,
5919                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5920                         return NF_DROP_ERR(-ECONNREFUSED);
5921         }
5922
5923         return NF_ACCEPT;
5924 }
5925 #endif  /* CONFIG_NETFILTER */
5926
5927 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5928 {
5929         int rc = 0;
5930         unsigned int msg_len;
5931         unsigned int data_len = skb->len;
5932         unsigned char *data = skb->data;
5933         struct nlmsghdr *nlh;
5934         struct sk_security_struct *sksec = sk->sk_security;
5935         u16 sclass = sksec->sclass;
5936         u32 perm;
5937
5938         while (data_len >= nlmsg_total_size(0)) {
5939                 nlh = (struct nlmsghdr *)data;
5940
5941                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5942                  *       users which means we can't reject skb's with bogus
5943                  *       length fields; our solution is to follow what
5944                  *       netlink_rcv_skb() does and simply skip processing at
5945                  *       messages with length fields that are clearly junk
5946                  */
5947                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5948                         return 0;
5949
5950                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5951                 if (rc == 0) {
5952                         rc = sock_has_perm(sk, perm);
5953                         if (rc)
5954                                 return rc;
5955                 } else if (rc == -EINVAL) {
5956                         /* -EINVAL is a missing msg/perm mapping */
5957                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5958                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5959                                 " pid=%d comm=%s\n",
5960                                 sk->sk_protocol, nlh->nlmsg_type,
5961                                 secclass_map[sclass - 1].name,
5962                                 task_pid_nr(current), current->comm);
5963                         if (enforcing_enabled() &&
5964                             !security_get_allow_unknown())
5965                                 return rc;
5966                         rc = 0;
5967                 } else if (rc == -ENOENT) {
5968                         /* -ENOENT is a missing socket/class mapping, ignore */
5969                         rc = 0;
5970                 } else {
5971                         return rc;
5972                 }
5973
5974                 /* move to the next message after applying netlink padding */
5975                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5976                 if (msg_len >= data_len)
5977                         return 0;
5978                 data_len -= msg_len;
5979                 data += msg_len;
5980         }
5981
5982         return rc;
5983 }
5984
5985 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5986 {
5987         isec->sclass = sclass;
5988         isec->sid = current_sid();
5989 }
5990
5991 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5992                         u32 perms)
5993 {
5994         struct ipc_security_struct *isec;
5995         struct common_audit_data ad;
5996         u32 sid = current_sid();
5997
5998         isec = selinux_ipc(ipc_perms);
5999
6000         ad.type = LSM_AUDIT_DATA_IPC;
6001         ad.u.ipc_id = ipc_perms->key;
6002
6003         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6004 }
6005
6006 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6007 {
6008         struct msg_security_struct *msec;
6009
6010         msec = selinux_msg_msg(msg);
6011         msec->sid = SECINITSID_UNLABELED;
6012
6013         return 0;
6014 }
6015
6016 /* message queue security operations */
6017 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6018 {
6019         struct ipc_security_struct *isec;
6020         struct common_audit_data ad;
6021         u32 sid = current_sid();
6022
6023         isec = selinux_ipc(msq);
6024         ipc_init_security(isec, SECCLASS_MSGQ);
6025
6026         ad.type = LSM_AUDIT_DATA_IPC;
6027         ad.u.ipc_id = msq->key;
6028
6029         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6030                             MSGQ__CREATE, &ad);
6031 }
6032
6033 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6034 {
6035         struct ipc_security_struct *isec;
6036         struct common_audit_data ad;
6037         u32 sid = current_sid();
6038
6039         isec = selinux_ipc(msq);
6040
6041         ad.type = LSM_AUDIT_DATA_IPC;
6042         ad.u.ipc_id = msq->key;
6043
6044         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6045                             MSGQ__ASSOCIATE, &ad);
6046 }
6047
6048 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6049 {
6050         u32 perms;
6051
6052         switch (cmd) {
6053         case IPC_INFO:
6054         case MSG_INFO:
6055                 /* No specific object, just general system-wide information. */
6056                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6057                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6058         case IPC_STAT:
6059         case MSG_STAT:
6060         case MSG_STAT_ANY:
6061                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6062                 break;
6063         case IPC_SET:
6064                 perms = MSGQ__SETATTR;
6065                 break;
6066         case IPC_RMID:
6067                 perms = MSGQ__DESTROY;
6068                 break;
6069         default:
6070                 return 0;
6071         }
6072
6073         return ipc_has_perm(msq, perms);
6074 }
6075
6076 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6077 {
6078         struct ipc_security_struct *isec;
6079         struct msg_security_struct *msec;
6080         struct common_audit_data ad;
6081         u32 sid = current_sid();
6082         int rc;
6083
6084         isec = selinux_ipc(msq);
6085         msec = selinux_msg_msg(msg);
6086
6087         /*
6088          * First time through, need to assign label to the message
6089          */
6090         if (msec->sid == SECINITSID_UNLABELED) {
6091                 /*
6092                  * Compute new sid based on current process and
6093                  * message queue this message will be stored in
6094                  */
6095                 rc = security_transition_sid(sid, isec->sid,
6096                                              SECCLASS_MSG, NULL, &msec->sid);
6097                 if (rc)
6098                         return rc;
6099         }
6100
6101         ad.type = LSM_AUDIT_DATA_IPC;
6102         ad.u.ipc_id = msq->key;
6103
6104         /* Can this process write to the queue? */
6105         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6106                           MSGQ__WRITE, &ad);
6107         if (!rc)
6108                 /* Can this process send the message */
6109                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6110                                   MSG__SEND, &ad);
6111         if (!rc)
6112                 /* Can the message be put in the queue? */
6113                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6114                                   MSGQ__ENQUEUE, &ad);
6115
6116         return rc;
6117 }
6118
6119 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6120                                     struct task_struct *target,
6121                                     long type, int mode)
6122 {
6123         struct ipc_security_struct *isec;
6124         struct msg_security_struct *msec;
6125         struct common_audit_data ad;
6126         u32 sid = task_sid_obj(target);
6127         int rc;
6128
6129         isec = selinux_ipc(msq);
6130         msec = selinux_msg_msg(msg);
6131
6132         ad.type = LSM_AUDIT_DATA_IPC;
6133         ad.u.ipc_id = msq->key;
6134
6135         rc = avc_has_perm(sid, isec->sid,
6136                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6137         if (!rc)
6138                 rc = avc_has_perm(sid, msec->sid,
6139                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6140         return rc;
6141 }
6142
6143 /* Shared Memory security operations */
6144 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6145 {
6146         struct ipc_security_struct *isec;
6147         struct common_audit_data ad;
6148         u32 sid = current_sid();
6149
6150         isec = selinux_ipc(shp);
6151         ipc_init_security(isec, SECCLASS_SHM);
6152
6153         ad.type = LSM_AUDIT_DATA_IPC;
6154         ad.u.ipc_id = shp->key;
6155
6156         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6157                             SHM__CREATE, &ad);
6158 }
6159
6160 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6161 {
6162         struct ipc_security_struct *isec;
6163         struct common_audit_data ad;
6164         u32 sid = current_sid();
6165
6166         isec = selinux_ipc(shp);
6167
6168         ad.type = LSM_AUDIT_DATA_IPC;
6169         ad.u.ipc_id = shp->key;
6170
6171         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6172                             SHM__ASSOCIATE, &ad);
6173 }
6174
6175 /* Note, at this point, shp is locked down */
6176 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6177 {
6178         u32 perms;
6179
6180         switch (cmd) {
6181         case IPC_INFO:
6182         case SHM_INFO:
6183                 /* No specific object, just general system-wide information. */
6184                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6185                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6186         case IPC_STAT:
6187         case SHM_STAT:
6188         case SHM_STAT_ANY:
6189                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6190                 break;
6191         case IPC_SET:
6192                 perms = SHM__SETATTR;
6193                 break;
6194         case SHM_LOCK:
6195         case SHM_UNLOCK:
6196                 perms = SHM__LOCK;
6197                 break;
6198         case IPC_RMID:
6199                 perms = SHM__DESTROY;
6200                 break;
6201         default:
6202                 return 0;
6203         }
6204
6205         return ipc_has_perm(shp, perms);
6206 }
6207
6208 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6209                              char __user *shmaddr, int shmflg)
6210 {
6211         u32 perms;
6212
6213         if (shmflg & SHM_RDONLY)
6214                 perms = SHM__READ;
6215         else
6216                 perms = SHM__READ | SHM__WRITE;
6217
6218         return ipc_has_perm(shp, perms);
6219 }
6220
6221 /* Semaphore security operations */
6222 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6223 {
6224         struct ipc_security_struct *isec;
6225         struct common_audit_data ad;
6226         u32 sid = current_sid();
6227
6228         isec = selinux_ipc(sma);
6229         ipc_init_security(isec, SECCLASS_SEM);
6230
6231         ad.type = LSM_AUDIT_DATA_IPC;
6232         ad.u.ipc_id = sma->key;
6233
6234         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6235                             SEM__CREATE, &ad);
6236 }
6237
6238 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6239 {
6240         struct ipc_security_struct *isec;
6241         struct common_audit_data ad;
6242         u32 sid = current_sid();
6243
6244         isec = selinux_ipc(sma);
6245
6246         ad.type = LSM_AUDIT_DATA_IPC;
6247         ad.u.ipc_id = sma->key;
6248
6249         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6250                             SEM__ASSOCIATE, &ad);
6251 }
6252
6253 /* Note, at this point, sma is locked down */
6254 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6255 {
6256         int err;
6257         u32 perms;
6258
6259         switch (cmd) {
6260         case IPC_INFO:
6261         case SEM_INFO:
6262                 /* No specific object, just general system-wide information. */
6263                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6264                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6265         case GETPID:
6266         case GETNCNT:
6267         case GETZCNT:
6268                 perms = SEM__GETATTR;
6269                 break;
6270         case GETVAL:
6271         case GETALL:
6272                 perms = SEM__READ;
6273                 break;
6274         case SETVAL:
6275         case SETALL:
6276                 perms = SEM__WRITE;
6277                 break;
6278         case IPC_RMID:
6279                 perms = SEM__DESTROY;
6280                 break;
6281         case IPC_SET:
6282                 perms = SEM__SETATTR;
6283                 break;
6284         case IPC_STAT:
6285         case SEM_STAT:
6286         case SEM_STAT_ANY:
6287                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6288                 break;
6289         default:
6290                 return 0;
6291         }
6292
6293         err = ipc_has_perm(sma, perms);
6294         return err;
6295 }
6296
6297 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6298                              struct sembuf *sops, unsigned nsops, int alter)
6299 {
6300         u32 perms;
6301
6302         if (alter)
6303                 perms = SEM__READ | SEM__WRITE;
6304         else
6305                 perms = SEM__READ;
6306
6307         return ipc_has_perm(sma, perms);
6308 }
6309
6310 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6311 {
6312         u32 av = 0;
6313
6314         av = 0;
6315         if (flag & S_IRUGO)
6316                 av |= IPC__UNIX_READ;
6317         if (flag & S_IWUGO)
6318                 av |= IPC__UNIX_WRITE;
6319
6320         if (av == 0)
6321                 return 0;
6322
6323         return ipc_has_perm(ipcp, av);
6324 }
6325
6326 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6327 {
6328         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6329         *secid = isec->sid;
6330 }
6331
6332 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6333 {
6334         if (inode)
6335                 inode_doinit_with_dentry(inode, dentry);
6336 }
6337
6338 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6339                                char **value)
6340 {
6341         const struct task_security_struct *tsec;
6342         int error;
6343         u32 sid;
6344         u32 len;
6345
6346         rcu_read_lock();
6347         tsec = selinux_cred(__task_cred(p));
6348         if (p != current) {
6349                 error = avc_has_perm(current_sid(), tsec->sid,
6350                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6351                 if (error)
6352                         goto err_unlock;
6353         }
6354         switch (attr) {
6355         case LSM_ATTR_CURRENT:
6356                 sid = tsec->sid;
6357                 break;
6358         case LSM_ATTR_PREV:
6359                 sid = tsec->osid;
6360                 break;
6361         case LSM_ATTR_EXEC:
6362                 sid = tsec->exec_sid;
6363                 break;
6364         case LSM_ATTR_FSCREATE:
6365                 sid = tsec->create_sid;
6366                 break;
6367         case LSM_ATTR_KEYCREATE:
6368                 sid = tsec->keycreate_sid;
6369                 break;
6370         case LSM_ATTR_SOCKCREATE:
6371                 sid = tsec->sockcreate_sid;
6372                 break;
6373         default:
6374                 error = -EOPNOTSUPP;
6375                 goto err_unlock;
6376         }
6377         rcu_read_unlock();
6378
6379         if (sid == SECSID_NULL) {
6380                 *value = NULL;
6381                 return 0;
6382         }
6383
6384         error = security_sid_to_context(sid, value, &len);
6385         if (error)
6386                 return error;
6387         return len;
6388
6389 err_unlock:
6390         rcu_read_unlock();
6391         return error;
6392 }
6393
6394 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6395 {
6396         struct task_security_struct *tsec;
6397         struct cred *new;
6398         u32 mysid = current_sid(), sid = 0, ptsid;
6399         int error;
6400         char *str = value;
6401
6402         /*
6403          * Basic control over ability to set these attributes at all.
6404          */
6405         switch (attr) {
6406         case LSM_ATTR_EXEC:
6407                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6408                                      PROCESS__SETEXEC, NULL);
6409                 break;
6410         case LSM_ATTR_FSCREATE:
6411                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6412                                      PROCESS__SETFSCREATE, NULL);
6413                 break;
6414         case LSM_ATTR_KEYCREATE:
6415                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6416                                      PROCESS__SETKEYCREATE, NULL);
6417                 break;
6418         case LSM_ATTR_SOCKCREATE:
6419                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6420                                      PROCESS__SETSOCKCREATE, NULL);
6421                 break;
6422         case LSM_ATTR_CURRENT:
6423                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6424                                      PROCESS__SETCURRENT, NULL);
6425                 break;
6426         default:
6427                 error = -EOPNOTSUPP;
6428                 break;
6429         }
6430         if (error)
6431                 return error;
6432
6433         /* Obtain a SID for the context, if one was specified. */
6434         if (size && str[0] && str[0] != '\n') {
6435                 if (str[size-1] == '\n') {
6436                         str[size-1] = 0;
6437                         size--;
6438                 }
6439                 error = security_context_to_sid(value, size,
6440                                                 &sid, GFP_KERNEL);
6441                 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6442                         if (!has_cap_mac_admin(true)) {
6443                                 struct audit_buffer *ab;
6444                                 size_t audit_size;
6445
6446                                 /* We strip a nul only if it is at the end,
6447                                  * otherwise the context contains a nul and
6448                                  * we should audit that */
6449                                 if (str[size - 1] == '\0')
6450                                         audit_size = size - 1;
6451                                 else
6452                                         audit_size = size;
6453                                 ab = audit_log_start(audit_context(),
6454                                                      GFP_ATOMIC,
6455                                                      AUDIT_SELINUX_ERR);
6456                                 if (!ab)
6457                                         return error;
6458                                 audit_log_format(ab, "op=fscreate invalid_context=");
6459                                 audit_log_n_untrustedstring(ab, value,
6460                                                             audit_size);
6461                                 audit_log_end(ab);
6462
6463                                 return error;
6464                         }
6465                         error = security_context_to_sid_force(value, size,
6466                                                         &sid);
6467                 }
6468                 if (error)
6469                         return error;
6470         }
6471
6472         new = prepare_creds();
6473         if (!new)
6474                 return -ENOMEM;
6475
6476         /* Permission checking based on the specified context is
6477            performed during the actual operation (execve,
6478            open/mkdir/...), when we know the full context of the
6479            operation.  See selinux_bprm_creds_for_exec for the execve
6480            checks and may_create for the file creation checks. The
6481            operation will then fail if the context is not permitted. */
6482         tsec = selinux_cred(new);
6483         if (attr == LSM_ATTR_EXEC) {
6484                 tsec->exec_sid = sid;
6485         } else if (attr == LSM_ATTR_FSCREATE) {
6486                 tsec->create_sid = sid;
6487         } else if (attr == LSM_ATTR_KEYCREATE) {
6488                 if (sid) {
6489                         error = avc_has_perm(mysid, sid,
6490                                              SECCLASS_KEY, KEY__CREATE, NULL);
6491                         if (error)
6492                                 goto abort_change;
6493                 }
6494                 tsec->keycreate_sid = sid;
6495         } else if (attr == LSM_ATTR_SOCKCREATE) {
6496                 tsec->sockcreate_sid = sid;
6497         } else if (attr == LSM_ATTR_CURRENT) {
6498                 error = -EINVAL;
6499                 if (sid == 0)
6500                         goto abort_change;
6501
6502                 if (!current_is_single_threaded()) {
6503                         error = security_bounded_transition(tsec->sid, sid);
6504                         if (error)
6505                                 goto abort_change;
6506                 }
6507
6508                 /* Check permissions for the transition. */
6509                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6510                                      PROCESS__DYNTRANSITION, NULL);
6511                 if (error)
6512                         goto abort_change;
6513
6514                 /* Check for ptracing, and update the task SID if ok.
6515                    Otherwise, leave SID unchanged and fail. */
6516                 ptsid = ptrace_parent_sid();
6517                 if (ptsid != 0) {
6518                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6519                                              PROCESS__PTRACE, NULL);
6520                         if (error)
6521                                 goto abort_change;
6522                 }
6523
6524                 tsec->sid = sid;
6525         } else {
6526                 error = -EINVAL;
6527                 goto abort_change;
6528         }
6529
6530         commit_creds(new);
6531         return size;
6532
6533 abort_change:
6534         abort_creds(new);
6535         return error;
6536 }
6537
6538 /**
6539  * selinux_getselfattr - Get SELinux current task attributes
6540  * @attr: the requested attribute
6541  * @ctx: buffer to receive the result
6542  * @size: buffer size (input), buffer size used (output)
6543  * @flags: unused
6544  *
6545  * Fill the passed user space @ctx with the details of the requested
6546  * attribute.
6547  *
6548  * Returns the number of attributes on success, an error code otherwise.
6549  * There will only ever be one attribute.
6550  */
6551 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6552                                u32 *size, u32 flags)
6553 {
6554         int rc;
6555         char *val = NULL;
6556         int val_len;
6557
6558         val_len = selinux_lsm_getattr(attr, current, &val);
6559         if (val_len < 0)
6560                 return val_len;
6561         rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6562         kfree(val);
6563         return (!rc ? 1 : rc);
6564 }
6565
6566 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6567                                u32 size, u32 flags)
6568 {
6569         int rc;
6570
6571         rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6572         if (rc > 0)
6573                 return 0;
6574         return rc;
6575 }
6576
6577 static int selinux_getprocattr(struct task_struct *p,
6578                                const char *name, char **value)
6579 {
6580         unsigned int attr = lsm_name_to_attr(name);
6581         int rc;
6582
6583         if (attr) {
6584                 rc = selinux_lsm_getattr(attr, p, value);
6585                 if (rc != -EOPNOTSUPP)
6586                         return rc;
6587         }
6588
6589         return -EINVAL;
6590 }
6591
6592 static int selinux_setprocattr(const char *name, void *value, size_t size)
6593 {
6594         int attr = lsm_name_to_attr(name);
6595
6596         if (attr)
6597                 return selinux_lsm_setattr(attr, value, size);
6598         return -EINVAL;
6599 }
6600
6601 static int selinux_ismaclabel(const char *name)
6602 {
6603         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6604 }
6605
6606 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6607 {
6608         return security_sid_to_context(secid,
6609                                        secdata, seclen);
6610 }
6611
6612 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6613 {
6614         return security_context_to_sid(secdata, seclen,
6615                                        secid, GFP_KERNEL);
6616 }
6617
6618 static void selinux_release_secctx(char *secdata, u32 seclen)
6619 {
6620         kfree(secdata);
6621 }
6622
6623 static void selinux_inode_invalidate_secctx(struct inode *inode)
6624 {
6625         struct inode_security_struct *isec = selinux_inode(inode);
6626
6627         spin_lock(&isec->lock);
6628         isec->initialized = LABEL_INVALID;
6629         spin_unlock(&isec->lock);
6630 }
6631
6632 /*
6633  *      called with inode->i_mutex locked
6634  */
6635 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6636 {
6637         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6638                                            ctx, ctxlen, 0);
6639         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6640         return rc == -EOPNOTSUPP ? 0 : rc;
6641 }
6642
6643 /*
6644  *      called with inode->i_mutex locked
6645  */
6646 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6647 {
6648         return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6649                                      ctx, ctxlen, 0);
6650 }
6651
6652 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6653 {
6654         int len = 0;
6655         len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6656                                         XATTR_SELINUX_SUFFIX, ctx, true);
6657         if (len < 0)
6658                 return len;
6659         *ctxlen = len;
6660         return 0;
6661 }
6662 #ifdef CONFIG_KEYS
6663
6664 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6665                              unsigned long flags)
6666 {
6667         const struct task_security_struct *tsec;
6668         struct key_security_struct *ksec;
6669
6670         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6671         if (!ksec)
6672                 return -ENOMEM;
6673
6674         tsec = selinux_cred(cred);
6675         if (tsec->keycreate_sid)
6676                 ksec->sid = tsec->keycreate_sid;
6677         else
6678                 ksec->sid = tsec->sid;
6679
6680         k->security = ksec;
6681         return 0;
6682 }
6683
6684 static void selinux_key_free(struct key *k)
6685 {
6686         struct key_security_struct *ksec = k->security;
6687
6688         k->security = NULL;
6689         kfree(ksec);
6690 }
6691
6692 static int selinux_key_permission(key_ref_t key_ref,
6693                                   const struct cred *cred,
6694                                   enum key_need_perm need_perm)
6695 {
6696         struct key *key;
6697         struct key_security_struct *ksec;
6698         u32 perm, sid;
6699
6700         switch (need_perm) {
6701         case KEY_NEED_VIEW:
6702                 perm = KEY__VIEW;
6703                 break;
6704         case KEY_NEED_READ:
6705                 perm = KEY__READ;
6706                 break;
6707         case KEY_NEED_WRITE:
6708                 perm = KEY__WRITE;
6709                 break;
6710         case KEY_NEED_SEARCH:
6711                 perm = KEY__SEARCH;
6712                 break;
6713         case KEY_NEED_LINK:
6714                 perm = KEY__LINK;
6715                 break;
6716         case KEY_NEED_SETATTR:
6717                 perm = KEY__SETATTR;
6718                 break;
6719         case KEY_NEED_UNLINK:
6720         case KEY_SYSADMIN_OVERRIDE:
6721         case KEY_AUTHTOKEN_OVERRIDE:
6722         case KEY_DEFER_PERM_CHECK:
6723                 return 0;
6724         default:
6725                 WARN_ON(1);
6726                 return -EPERM;
6727
6728         }
6729
6730         sid = cred_sid(cred);
6731         key = key_ref_to_ptr(key_ref);
6732         ksec = key->security;
6733
6734         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6735 }
6736
6737 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6738 {
6739         struct key_security_struct *ksec = key->security;
6740         char *context = NULL;
6741         unsigned len;
6742         int rc;
6743
6744         rc = security_sid_to_context(ksec->sid,
6745                                      &context, &len);
6746         if (!rc)
6747                 rc = len;
6748         *_buffer = context;
6749         return rc;
6750 }
6751
6752 #ifdef CONFIG_KEY_NOTIFICATIONS
6753 static int selinux_watch_key(struct key *key)
6754 {
6755         struct key_security_struct *ksec = key->security;
6756         u32 sid = current_sid();
6757
6758         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6759 }
6760 #endif
6761 #endif
6762
6763 #ifdef CONFIG_SECURITY_INFINIBAND
6764 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6765 {
6766         struct common_audit_data ad;
6767         int err;
6768         u32 sid = 0;
6769         struct ib_security_struct *sec = ib_sec;
6770         struct lsm_ibpkey_audit ibpkey;
6771
6772         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6773         if (err)
6774                 return err;
6775
6776         ad.type = LSM_AUDIT_DATA_IBPKEY;
6777         ibpkey.subnet_prefix = subnet_prefix;
6778         ibpkey.pkey = pkey_val;
6779         ad.u.ibpkey = &ibpkey;
6780         return avc_has_perm(sec->sid, sid,
6781                             SECCLASS_INFINIBAND_PKEY,
6782                             INFINIBAND_PKEY__ACCESS, &ad);
6783 }
6784
6785 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6786                                             u8 port_num)
6787 {
6788         struct common_audit_data ad;
6789         int err;
6790         u32 sid = 0;
6791         struct ib_security_struct *sec = ib_sec;
6792         struct lsm_ibendport_audit ibendport;
6793
6794         err = security_ib_endport_sid(dev_name, port_num,
6795                                       &sid);
6796
6797         if (err)
6798                 return err;
6799
6800         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6801         ibendport.dev_name = dev_name;
6802         ibendport.port = port_num;
6803         ad.u.ibendport = &ibendport;
6804         return avc_has_perm(sec->sid, sid,
6805                             SECCLASS_INFINIBAND_ENDPORT,
6806                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6807 }
6808
6809 static int selinux_ib_alloc_security(void **ib_sec)
6810 {
6811         struct ib_security_struct *sec;
6812
6813         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6814         if (!sec)
6815                 return -ENOMEM;
6816         sec->sid = current_sid();
6817
6818         *ib_sec = sec;
6819         return 0;
6820 }
6821
6822 static void selinux_ib_free_security(void *ib_sec)
6823 {
6824         kfree(ib_sec);
6825 }
6826 #endif
6827
6828 #ifdef CONFIG_BPF_SYSCALL
6829 static int selinux_bpf(int cmd, union bpf_attr *attr,
6830                                      unsigned int size)
6831 {
6832         u32 sid = current_sid();
6833         int ret;
6834
6835         switch (cmd) {
6836         case BPF_MAP_CREATE:
6837                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6838                                    NULL);
6839                 break;
6840         case BPF_PROG_LOAD:
6841                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6842                                    NULL);
6843                 break;
6844         default:
6845                 ret = 0;
6846                 break;
6847         }
6848
6849         return ret;
6850 }
6851
6852 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6853 {
6854         u32 av = 0;
6855
6856         if (fmode & FMODE_READ)
6857                 av |= BPF__MAP_READ;
6858         if (fmode & FMODE_WRITE)
6859                 av |= BPF__MAP_WRITE;
6860         return av;
6861 }
6862
6863 /* This function will check the file pass through unix socket or binder to see
6864  * if it is a bpf related object. And apply corresponding checks on the bpf
6865  * object based on the type. The bpf maps and programs, not like other files and
6866  * socket, are using a shared anonymous inode inside the kernel as their inode.
6867  * So checking that inode cannot identify if the process have privilege to
6868  * access the bpf object and that's why we have to add this additional check in
6869  * selinux_file_receive and selinux_binder_transfer_files.
6870  */
6871 static int bpf_fd_pass(const struct file *file, u32 sid)
6872 {
6873         struct bpf_security_struct *bpfsec;
6874         struct bpf_prog *prog;
6875         struct bpf_map *map;
6876         int ret;
6877
6878         if (file->f_op == &bpf_map_fops) {
6879                 map = file->private_data;
6880                 bpfsec = map->security;
6881                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6882                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6883                 if (ret)
6884                         return ret;
6885         } else if (file->f_op == &bpf_prog_fops) {
6886                 prog = file->private_data;
6887                 bpfsec = prog->aux->security;
6888                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6889                                    BPF__PROG_RUN, NULL);
6890                 if (ret)
6891                         return ret;
6892         }
6893         return 0;
6894 }
6895
6896 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6897 {
6898         u32 sid = current_sid();
6899         struct bpf_security_struct *bpfsec;
6900
6901         bpfsec = map->security;
6902         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6903                             bpf_map_fmode_to_av(fmode), NULL);
6904 }
6905
6906 static int selinux_bpf_prog(struct bpf_prog *prog)
6907 {
6908         u32 sid = current_sid();
6909         struct bpf_security_struct *bpfsec;
6910
6911         bpfsec = prog->aux->security;
6912         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6913                             BPF__PROG_RUN, NULL);
6914 }
6915
6916 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6917                                   struct bpf_token *token)
6918 {
6919         struct bpf_security_struct *bpfsec;
6920
6921         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6922         if (!bpfsec)
6923                 return -ENOMEM;
6924
6925         bpfsec->sid = current_sid();
6926         map->security = bpfsec;
6927
6928         return 0;
6929 }
6930
6931 static void selinux_bpf_map_free(struct bpf_map *map)
6932 {
6933         struct bpf_security_struct *bpfsec = map->security;
6934
6935         map->security = NULL;
6936         kfree(bpfsec);
6937 }
6938
6939 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6940                                  struct bpf_token *token)
6941 {
6942         struct bpf_security_struct *bpfsec;
6943
6944         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6945         if (!bpfsec)
6946                 return -ENOMEM;
6947
6948         bpfsec->sid = current_sid();
6949         prog->aux->security = bpfsec;
6950
6951         return 0;
6952 }
6953
6954 static void selinux_bpf_prog_free(struct bpf_prog *prog)
6955 {
6956         struct bpf_security_struct *bpfsec = prog->aux->security;
6957
6958         prog->aux->security = NULL;
6959         kfree(bpfsec);
6960 }
6961
6962 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
6963                                     struct path *path)
6964 {
6965         struct bpf_security_struct *bpfsec;
6966
6967         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6968         if (!bpfsec)
6969                 return -ENOMEM;
6970
6971         bpfsec->sid = current_sid();
6972         token->security = bpfsec;
6973
6974         return 0;
6975 }
6976
6977 static void selinux_bpf_token_free(struct bpf_token *token)
6978 {
6979         struct bpf_security_struct *bpfsec = token->security;
6980
6981         token->security = NULL;
6982         kfree(bpfsec);
6983 }
6984 #endif
6985
6986 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
6987         .lbs_cred = sizeof(struct task_security_struct),
6988         .lbs_file = sizeof(struct file_security_struct),
6989         .lbs_inode = sizeof(struct inode_security_struct),
6990         .lbs_ipc = sizeof(struct ipc_security_struct),
6991         .lbs_msg_msg = sizeof(struct msg_security_struct),
6992         .lbs_superblock = sizeof(struct superblock_security_struct),
6993         .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
6994 };
6995
6996 #ifdef CONFIG_PERF_EVENTS
6997 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6998 {
6999         u32 requested, sid = current_sid();
7000
7001         if (type == PERF_SECURITY_OPEN)
7002                 requested = PERF_EVENT__OPEN;
7003         else if (type == PERF_SECURITY_CPU)
7004                 requested = PERF_EVENT__CPU;
7005         else if (type == PERF_SECURITY_KERNEL)
7006                 requested = PERF_EVENT__KERNEL;
7007         else if (type == PERF_SECURITY_TRACEPOINT)
7008                 requested = PERF_EVENT__TRACEPOINT;
7009         else
7010                 return -EINVAL;
7011
7012         return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7013                             requested, NULL);
7014 }
7015
7016 static int selinux_perf_event_alloc(struct perf_event *event)
7017 {
7018         struct perf_event_security_struct *perfsec;
7019
7020         perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
7021         if (!perfsec)
7022                 return -ENOMEM;
7023
7024         perfsec->sid = current_sid();
7025         event->security = perfsec;
7026
7027         return 0;
7028 }
7029
7030 static void selinux_perf_event_free(struct perf_event *event)
7031 {
7032         struct perf_event_security_struct *perfsec = event->security;
7033
7034         event->security = NULL;
7035         kfree(perfsec);
7036 }
7037
7038 static int selinux_perf_event_read(struct perf_event *event)
7039 {
7040         struct perf_event_security_struct *perfsec = event->security;
7041         u32 sid = current_sid();
7042
7043         return avc_has_perm(sid, perfsec->sid,
7044                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7045 }
7046
7047 static int selinux_perf_event_write(struct perf_event *event)
7048 {
7049         struct perf_event_security_struct *perfsec = event->security;
7050         u32 sid = current_sid();
7051
7052         return avc_has_perm(sid, perfsec->sid,
7053                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7054 }
7055 #endif
7056
7057 #ifdef CONFIG_IO_URING
7058 /**
7059  * selinux_uring_override_creds - check the requested cred override
7060  * @new: the target creds
7061  *
7062  * Check to see if the current task is allowed to override it's credentials
7063  * to service an io_uring operation.
7064  */
7065 static int selinux_uring_override_creds(const struct cred *new)
7066 {
7067         return avc_has_perm(current_sid(), cred_sid(new),
7068                             SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7069 }
7070
7071 /**
7072  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7073  *
7074  * Check to see if the current task is allowed to create a new io_uring
7075  * kernel polling thread.
7076  */
7077 static int selinux_uring_sqpoll(void)
7078 {
7079         u32 sid = current_sid();
7080
7081         return avc_has_perm(sid, sid,
7082                             SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7083 }
7084
7085 /**
7086  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7087  * @ioucmd: the io_uring command structure
7088  *
7089  * Check to see if the current domain is allowed to execute an
7090  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7091  *
7092  */
7093 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7094 {
7095         struct file *file = ioucmd->file;
7096         struct inode *inode = file_inode(file);
7097         struct inode_security_struct *isec = selinux_inode(inode);
7098         struct common_audit_data ad;
7099
7100         ad.type = LSM_AUDIT_DATA_FILE;
7101         ad.u.file = file;
7102
7103         return avc_has_perm(current_sid(), isec->sid,
7104                             SECCLASS_IO_URING, IO_URING__CMD, &ad);
7105 }
7106 #endif /* CONFIG_IO_URING */
7107
7108 static const struct lsm_id selinux_lsmid = {
7109         .name = "selinux",
7110         .id = LSM_ID_SELINUX,
7111 };
7112
7113 /*
7114  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7115  * 1. any hooks that don't belong to (2.) or (3.) below,
7116  * 2. hooks that both access structures allocated by other hooks, and allocate
7117  *    structures that can be later accessed by other hooks (mostly "cloning"
7118  *    hooks),
7119  * 3. hooks that only allocate structures that can be later accessed by other
7120  *    hooks ("allocating" hooks).
7121  *
7122  * Please follow block comment delimiters in the list to keep this order.
7123  */
7124 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7125         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7126         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7127         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7128         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7129
7130         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7131         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7132         LSM_HOOK_INIT(capget, selinux_capget),
7133         LSM_HOOK_INIT(capset, selinux_capset),
7134         LSM_HOOK_INIT(capable, selinux_capable),
7135         LSM_HOOK_INIT(quotactl, selinux_quotactl),
7136         LSM_HOOK_INIT(quota_on, selinux_quota_on),
7137         LSM_HOOK_INIT(syslog, selinux_syslog),
7138         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7139
7140         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7141
7142         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7143         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7144         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7145
7146         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7147         LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7148         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7149         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7150         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7151         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7152         LSM_HOOK_INIT(sb_mount, selinux_mount),
7153         LSM_HOOK_INIT(sb_umount, selinux_umount),
7154         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7155         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7156
7157         LSM_HOOK_INIT(move_mount, selinux_move_mount),
7158
7159         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7160         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7161
7162         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7163         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7164         LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7165         LSM_HOOK_INIT(inode_create, selinux_inode_create),
7166         LSM_HOOK_INIT(inode_link, selinux_inode_link),
7167         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7168         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7169         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7170         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7171         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7172         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7173         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7174         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7175         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7176         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7177         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7178         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7179         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7180         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7181         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7182         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7183         LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7184         LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7185         LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7186         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7187         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7188         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7189         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7190         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7191         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7192         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7193
7194         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7195
7196         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7197         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7198         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7199         LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7200         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7201         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7202         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7203         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7204         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7205         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7206         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7207         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7208
7209         LSM_HOOK_INIT(file_open, selinux_file_open),
7210
7211         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7212         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7213         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7214         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7215         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7216         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7217         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7218         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7219         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7220         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7221         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7222         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7223         LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj),
7224         LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7225         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7226         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7227         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7228         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7229         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7230         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7231         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7232         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7233         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7234         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7235         LSM_HOOK_INIT(userns_create, selinux_userns_create),
7236
7237         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7238         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7239
7240         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7241         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7242         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7243         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7244
7245         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7246         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7247         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7248
7249         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7250         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7251         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7252
7253         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7254
7255         LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7256         LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7257         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7258         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7259
7260         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7261         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7262         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7263         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7264         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7265         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7266
7267         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7268         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7269
7270         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7271         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7272         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7273         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7274         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7275         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7276         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7277         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7278         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7279         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7280         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7281         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7282         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7283         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7284         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7285         LSM_HOOK_INIT(socket_getpeersec_stream,
7286                         selinux_socket_getpeersec_stream),
7287         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7288         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7289         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7290         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7291         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7292         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7293         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7294         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7295         LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7296         LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7297         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7298         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7299         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7300         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7301         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7302         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7303         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7304         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7305         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7306         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7307         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7308         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7309 #ifdef CONFIG_SECURITY_INFINIBAND
7310         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7311         LSM_HOOK_INIT(ib_endport_manage_subnet,
7312                       selinux_ib_endport_manage_subnet),
7313         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7314 #endif
7315 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7316         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7317         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7318         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7319         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7320         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7321         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7322                         selinux_xfrm_state_pol_flow_match),
7323         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7324 #endif
7325
7326 #ifdef CONFIG_KEYS
7327         LSM_HOOK_INIT(key_free, selinux_key_free),
7328         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7329         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7330 #ifdef CONFIG_KEY_NOTIFICATIONS
7331         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7332 #endif
7333 #endif
7334
7335 #ifdef CONFIG_AUDIT
7336         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7337         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7338         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7339 #endif
7340
7341 #ifdef CONFIG_BPF_SYSCALL
7342         LSM_HOOK_INIT(bpf, selinux_bpf),
7343         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7344         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7345         LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7346         LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7347         LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7348 #endif
7349
7350 #ifdef CONFIG_PERF_EVENTS
7351         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7352         LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7353         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7354         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7355 #endif
7356
7357 #ifdef CONFIG_IO_URING
7358         LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7359         LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7360         LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7361 #endif
7362
7363         /*
7364          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7365          */
7366         LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7367         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7368         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7369         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7370 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7371         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7372 #endif
7373
7374         /*
7375          * PUT "ALLOCATING" HOOKS HERE
7376          */
7377         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7378         LSM_HOOK_INIT(msg_queue_alloc_security,
7379                       selinux_msg_queue_alloc_security),
7380         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7381         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7382         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7383         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7384         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7385         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7386         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7387         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7388 #ifdef CONFIG_SECURITY_INFINIBAND
7389         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7390 #endif
7391 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7392         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7393         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7394         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7395                       selinux_xfrm_state_alloc_acquire),
7396 #endif
7397 #ifdef CONFIG_KEYS
7398         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7399 #endif
7400 #ifdef CONFIG_AUDIT
7401         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7402 #endif
7403 #ifdef CONFIG_BPF_SYSCALL
7404         LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7405         LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7406         LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7407 #endif
7408 #ifdef CONFIG_PERF_EVENTS
7409         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7410 #endif
7411 };
7412
7413 static __init int selinux_init(void)
7414 {
7415         pr_info("SELinux:  Initializing.\n");
7416
7417         memset(&selinux_state, 0, sizeof(selinux_state));
7418         enforcing_set(selinux_enforcing_boot);
7419         selinux_avc_init();
7420         mutex_init(&selinux_state.status_lock);
7421         mutex_init(&selinux_state.policy_mutex);
7422
7423         /* Set the security state for the initial task. */
7424         cred_init_security();
7425
7426         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7427         if (!default_noexec)
7428                 pr_notice("SELinux:  virtual memory is executable by default\n");
7429
7430         avc_init();
7431
7432         avtab_cache_init();
7433
7434         ebitmap_cache_init();
7435
7436         hashtab_cache_init();
7437
7438         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7439                            &selinux_lsmid);
7440
7441         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7442                 panic("SELinux: Unable to register AVC netcache callback\n");
7443
7444         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7445                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7446
7447         if (selinux_enforcing_boot)
7448                 pr_debug("SELinux:  Starting in enforcing mode\n");
7449         else
7450                 pr_debug("SELinux:  Starting in permissive mode\n");
7451
7452         fs_validate_description("selinux", selinux_fs_parameters);
7453
7454         return 0;
7455 }
7456
7457 static void delayed_superblock_init(struct super_block *sb, void *unused)
7458 {
7459         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7460 }
7461
7462 void selinux_complete_init(void)
7463 {
7464         pr_debug("SELinux:  Completing initialization.\n");
7465
7466         /* Set up any superblocks initialized prior to the policy load. */
7467         pr_debug("SELinux:  Setting up existing superblocks.\n");
7468         iterate_supers(delayed_superblock_init, NULL);
7469 }
7470
7471 /* SELinux requires early initialization in order to label
7472    all processes and objects when they are created. */
7473 DEFINE_LSM(selinux) = {
7474         .name = "selinux",
7475         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7476         .enabled = &selinux_enabled_boot,
7477         .blobs = &selinux_blob_sizes,
7478         .init = selinux_init,
7479 };
7480
7481 #if defined(CONFIG_NETFILTER)
7482 static const struct nf_hook_ops selinux_nf_ops[] = {
7483         {
7484                 .hook =         selinux_ip_postroute,
7485                 .pf =           NFPROTO_IPV4,
7486                 .hooknum =      NF_INET_POST_ROUTING,
7487                 .priority =     NF_IP_PRI_SELINUX_LAST,
7488         },
7489         {
7490                 .hook =         selinux_ip_forward,
7491                 .pf =           NFPROTO_IPV4,
7492                 .hooknum =      NF_INET_FORWARD,
7493                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7494         },
7495         {
7496                 .hook =         selinux_ip_output,
7497                 .pf =           NFPROTO_IPV4,
7498                 .hooknum =      NF_INET_LOCAL_OUT,
7499                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7500         },
7501 #if IS_ENABLED(CONFIG_IPV6)
7502         {
7503                 .hook =         selinux_ip_postroute,
7504                 .pf =           NFPROTO_IPV6,
7505                 .hooknum =      NF_INET_POST_ROUTING,
7506                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7507         },
7508         {
7509                 .hook =         selinux_ip_forward,
7510                 .pf =           NFPROTO_IPV6,
7511                 .hooknum =      NF_INET_FORWARD,
7512                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7513         },
7514         {
7515                 .hook =         selinux_ip_output,
7516                 .pf =           NFPROTO_IPV6,
7517                 .hooknum =      NF_INET_LOCAL_OUT,
7518                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7519         },
7520 #endif  /* IPV6 */
7521 };
7522
7523 static int __net_init selinux_nf_register(struct net *net)
7524 {
7525         return nf_register_net_hooks(net, selinux_nf_ops,
7526                                      ARRAY_SIZE(selinux_nf_ops));
7527 }
7528
7529 static void __net_exit selinux_nf_unregister(struct net *net)
7530 {
7531         nf_unregister_net_hooks(net, selinux_nf_ops,
7532                                 ARRAY_SIZE(selinux_nf_ops));
7533 }
7534
7535 static struct pernet_operations selinux_net_ops = {
7536         .init = selinux_nf_register,
7537         .exit = selinux_nf_unregister,
7538 };
7539
7540 static int __init selinux_nf_ip_init(void)
7541 {
7542         int err;
7543
7544         if (!selinux_enabled_boot)
7545                 return 0;
7546
7547         pr_debug("SELinux:  Registering netfilter hooks\n");
7548
7549         err = register_pernet_subsys(&selinux_net_ops);
7550         if (err)
7551                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7552
7553         return 0;
7554 }
7555 __initcall(selinux_nf_ip_init);
7556 #endif /* CONFIG_NETFILTER */