security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <[email protected]>
   7  *            Chris Vance, <[email protected]>
   8  *            Wayne Salamon, <[email protected]>
   9  *            James Morris <[email protected]>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <[email protected]>
  13  *                                         Eric Paris <[email protected]>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <[email protected]>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <[email protected]>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <[email protected]>
  20  *  Copyright (C) 2016 Mellanox Technologies
  21  *
  22  *      This program is free software; you can redistribute it and/or modify
  23  *      it under the terms of the GNU General Public License version 2,
  24  *      as published by the Free Software Foundation.
  25  */
  26
  27 #include <linux/init.h>
  28 #include <linux/kd.h>
  29 #include <linux/kernel.h>
  30 #include <linux/tracehook.h>
  31 #include <linux/errno.h>
  32 #include <linux/sched/signal.h>
  33 #include <linux/sched/task.h>
  34 #include <linux/lsm_hooks.h>
  35 #include <linux/xattr.h>
  36 #include <linux/capability.h>
  37 #include <linux/unistd.h>
  38 #include <linux/mm.h>
  39 #include <linux/mman.h>
  40 #include <linux/slab.h>
  41 #include <linux/pagemap.h>
  42 #include <linux/proc_fs.h>
  43 #include <linux/swap.h>
  44 #include <linux/spinlock.h>
  45 #include <linux/syscalls.h>
  46 #include <linux/dcache.h>
  47 #include <linux/file.h>
  48 #include <linux/fdtable.h>
  49 #include <linux/namei.h>
  50 #include <linux/mount.h>
  51 #include <linux/netfilter_ipv4.h>
  52 #include <linux/netfilter_ipv6.h>
  53 #include <linux/tty.h>
  54 #include <net/icmp.h>
  55 #include <net/ip.h>             /* for local_port_range[] */
  56 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  57 #include <net/inet_connection_sock.h>
  58 #include <net/net_namespace.h>
  59 #include <net/netlabel.h>
  60 #include <linux/uaccess.h>
  61 #include <asm/ioctls.h>
  62 #include <linux/atomic.h>
  63 #include <linux/bitops.h>
  64 #include <linux/interrupt.h>
  65 #include <linux/netdevice.h>    /* for network interface checks */
  66 #include <net/netlink.h>
  67 #include <linux/tcp.h>
  68 #include <linux/udp.h>
  69 #include <linux/dccp.h>
  70 #include <linux/sctp.h>
  71 #include <net/sctp/structs.h>
  72 #include <linux/quota.h>
  73 #include <linux/un.h>           /* for Unix socket types */
  74 #include <net/af_unix.h>        /* for Unix socket types */
  75 #include <linux/parser.h>
  76 #include <linux/nfs_mount.h>
  77 #include <net/ipv6.h>
  78 #include <linux/hugetlb.h>
  79 #include <linux/personality.h>
  80 #include <linux/audit.h>
  81 #include <linux/string.h>
  82 #include <linux/selinux.h>
  83 #include <linux/mutex.h>
  84 #include <linux/posix-timers.h>
  85 #include <linux/syslog.h>
  86 #include <linux/user_namespace.h>
  87 #include <linux/export.h>
  88 #include <linux/msg.h>
  89 #include <linux/shm.h>
  90 #include <linux/bpf.h>
  91
  92 #include "avc.h"
  93 #include "objsec.h"
  94 #include "netif.h"
  95 #include "netnode.h"
  96 #include "netport.h"
  97 #include "ibpkey.h"
  98 #include "xfrm.h"
  99 #include "netlabel.h"
 100 #include "audit.h"
 101 #include "avc_ss.h"
 102
 103 struct selinux_state selinux_state;
 104
 105 /* SECMARK reference count */
 106 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 107
 108 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 109 static int selinux_enforcing_boot;
 110
 111 static int __init enforcing_setup(char *str)
 112 {
 113         unsigned long enforcing;
 114         if (!kstrtoul(str, 0, &enforcing))
 115                 selinux_enforcing_boot = enforcing ? 1 : 0;
 116         return 1;
 117 }
 118 __setup("enforcing=", enforcing_setup);
 119 #else
 120 #define selinux_enforcing_boot 1
 121 #endif
 122
 123 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 124 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 125
 126 static int __init selinux_enabled_setup(char *str)
 127 {
 128         unsigned long enabled;
 129         if (!kstrtoul(str, 0, &enabled))
 130                 selinux_enabled = enabled ? 1 : 0;
 131         return 1;
 132 }
 133 __setup("selinux=", selinux_enabled_setup);
 134 #else
 135 int selinux_enabled = 1;
 136 #endif
 137
 138 static unsigned int selinux_checkreqprot_boot =
 139         CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
 140
 141 static int __init checkreqprot_setup(char *str)
 142 {
 143         unsigned long checkreqprot;
 144
 145         if (!kstrtoul(str, 0, &checkreqprot))
 146                 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
 147         return 1;
 148 }
 149 __setup("checkreqprot=", checkreqprot_setup);
 150
 151 static struct kmem_cache *sel_inode_cache;
 152 static struct kmem_cache *file_security_cache;
 153
 154 /**
 155  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 156  *
 157  * Description:
 158  * This function checks the SECMARK reference counter to see if any SECMARK
 159  * targets are currently configured, if the reference counter is greater than
 160  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 161  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 162  * policy capability is enabled, SECMARK is always considered enabled.
 163  *
 164  */
 165 static int selinux_secmark_enabled(void)
 166 {
 167         return (selinux_policycap_alwaysnetwork() ||
 168                 atomic_read(&selinux_secmark_refcount));
 169 }
 170
 171 /**
 172  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 173  *
 174  * Description:
 175  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 176  * (1) if any are enabled or false (0) if neither are enabled.  If the
 177  * always_check_network policy capability is enabled, peer labeling
 178  * is always considered enabled.
 179  *
 180  */
 181 static int selinux_peerlbl_enabled(void)
 182 {
 183         return (selinux_policycap_alwaysnetwork() ||
 184                 netlbl_enabled() || selinux_xfrm_enabled());
 185 }
 186
 187 static int selinux_netcache_avc_callback(u32 event)
 188 {
 189         if (event == AVC_CALLBACK_RESET) {
 190                 sel_netif_flush();
 191                 sel_netnode_flush();
 192                 sel_netport_flush();
 193                 synchronize_net();
 194         }
 195         return 0;
 196 }
 197
 198 static int selinux_lsm_notifier_avc_callback(u32 event)
 199 {
 200         if (event == AVC_CALLBACK_RESET) {
 201                 sel_ib_pkey_flush();
 202                 call_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 203         }
 204
 205         return 0;
 206 }
 207
 208 /*
 209  * initialise the security for the init task
 210  */
 211 static void cred_init_security(void)
 212 {
 213         struct cred *cred = (struct cred *) current->real_cred;
 214         struct task_security_struct *tsec;
 215
 216         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 217         if (!tsec)
 218                 panic("SELinux:  Failed to initialize initial task.\n");
 219
 220         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 221         cred->security = tsec;
 222 }
 223
 224 /*
 225  * get the security ID of a set of credentials
 226  */
 227 static inline u32 cred_sid(const struct cred *cred)
 228 {
 229         const struct task_security_struct *tsec;
 230
 231         tsec = cred->security;
 232         return tsec->sid;
 233 }
 234
 235 /*
 236  * get the objective security ID of a task
 237  */
 238 static inline u32 task_sid(const struct task_struct *task)
 239 {
 240         u32 sid;
 241
 242         rcu_read_lock();
 243         sid = cred_sid(__task_cred(task));
 244         rcu_read_unlock();
 245         return sid;
 246 }
 247
 248 /* Allocate and free functions for each kind of security blob. */
 249
 250 static int inode_alloc_security(struct inode *inode)
 251 {
 252         struct inode_security_struct *isec;
 253         u32 sid = current_sid();
 254
 255         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 256         if (!isec)
 257                 return -ENOMEM;
 258
 259         spin_lock_init(&isec->lock);
 260         INIT_LIST_HEAD(&isec->list);
 261         isec->inode = inode;
 262         isec->sid = SECINITSID_UNLABELED;
 263         isec->sclass = SECCLASS_FILE;
 264         isec->task_sid = sid;
 265         isec->initialized = LABEL_INVALID;
 266         inode->i_security = isec;
 267
 268         return 0;
 269 }
 270
 271 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 272
 273 /*
 274  * Try reloading inode security labels that have been marked as invalid.  The
 275  * @may_sleep parameter indicates when sleeping and thus reloading labels is
 276  * allowed; when set to false, returns -ECHILD when the label is
 277  * invalid.  The @opt_dentry parameter should be set to a dentry of the inode;
 278  * when no dentry is available, set it to NULL instead.
 279  */
 280 static int __inode_security_revalidate(struct inode *inode,
 281                                        struct dentry *opt_dentry,
 282                                        bool may_sleep)
 283 {
 284         struct inode_security_struct *isec = inode->i_security;
 285
 286         might_sleep_if(may_sleep);
 287
 288         if (selinux_state.initialized &&
 289             isec->initialized != LABEL_INITIALIZED) {
 290                 if (!may_sleep)
 291                         return -ECHILD;
 292
 293                 /*
 294                  * Try reloading the inode security label.  This will fail if
 295                  * @opt_dentry is NULL and no dentry for this inode can be
 296                  * found; in that case, continue using the old label.
 297                  */
 298                 inode_doinit_with_dentry(inode, opt_dentry);
 299         }
 300         return 0;
 301 }
 302
 303 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 304 {
 305         return inode->i_security;
 306 }
 307
 308 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 309 {
 310         int error;
 311
 312         error = __inode_security_revalidate(inode, NULL, !rcu);
 313         if (error)
 314                 return ERR_PTR(error);
 315         return inode->i_security;
 316 }
 317
 318 /*
 319  * Get the security label of an inode.
 320  */
 321 static struct inode_security_struct *inode_security(struct inode *inode)
 322 {
 323         __inode_security_revalidate(inode, NULL, true);
 324         return inode->i_security;
 325 }
 326
 327 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 328 {
 329         struct inode *inode = d_backing_inode(dentry);
 330
 331         return inode->i_security;
 332 }
 333
 334 /*
 335  * Get the security label of a dentry's backing inode.
 336  */
 337 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 338 {
 339         struct inode *inode = d_backing_inode(dentry);
 340
 341         __inode_security_revalidate(inode, dentry, true);
 342         return inode->i_security;
 343 }
 344
 345 static void inode_free_rcu(struct rcu_head *head)
 346 {
 347         struct inode_security_struct *isec;
 348
 349         isec = container_of(head, struct inode_security_struct, rcu);
 350         kmem_cache_free(sel_inode_cache, isec);
 351 }
 352
 353 static void inode_free_security(struct inode *inode)
 354 {
 355         struct inode_security_struct *isec = inode->i_security;
 356         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 357
 358         /*
 359          * As not all inode security structures are in a list, we check for
 360          * empty list outside of the lock to make sure that we won't waste
 361          * time taking a lock doing nothing.
 362          *
 363          * The list_del_init() function can be safely called more than once.
 364          * It should not be possible for this function to be called with
 365          * concurrent list_add(), but for better safety against future changes
 366          * in the code, we use list_empty_careful() here.
 367          */
 368         if (!list_empty_careful(&isec->list)) {
 369                 spin_lock(&sbsec->isec_lock);
 370                 list_del_init(&isec->list);
 371                 spin_unlock(&sbsec->isec_lock);
 372         }
 373
 374         /*
 375          * The inode may still be referenced in a path walk and
 376          * a call to selinux_inode_permission() can be made
 377          * after inode_free_security() is called. Ideally, the VFS
 378          * wouldn't do this, but fixing that is a much harder
 379          * job. For now, simply free the i_security via RCU, and
 380          * leave the current inode->i_security pointer intact.
 381          * The inode will be freed after the RCU grace period too.
 382          */
 383         call_rcu(&isec->rcu, inode_free_rcu);
 384 }
 385
 386 static int file_alloc_security(struct file *file)
 387 {
 388         struct file_security_struct *fsec;
 389         u32 sid = current_sid();
 390
 391         fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
 392         if (!fsec)
 393                 return -ENOMEM;
 394
 395         fsec->sid = sid;
 396         fsec->fown_sid = sid;
 397         file->f_security = fsec;
 398
 399         return 0;
 400 }
 401
 402 static void file_free_security(struct file *file)
 403 {
 404         struct file_security_struct *fsec = file->f_security;
 405         file->f_security = NULL;
 406         kmem_cache_free(file_security_cache, fsec);
 407 }
 408
 409 static int superblock_alloc_security(struct super_block *sb)
 410 {
 411         struct superblock_security_struct *sbsec;
 412
 413         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 414         if (!sbsec)
 415                 return -ENOMEM;
 416
 417         mutex_init(&sbsec->lock);
 418         INIT_LIST_HEAD(&sbsec->isec_head);
 419         spin_lock_init(&sbsec->isec_lock);
 420         sbsec->sb = sb;
 421         sbsec->sid = SECINITSID_UNLABELED;
 422         sbsec->def_sid = SECINITSID_FILE;
 423         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 424         sb->s_security = sbsec;
 425
 426         return 0;
 427 }
 428
 429 static void superblock_free_security(struct super_block *sb)
 430 {
 431         struct superblock_security_struct *sbsec = sb->s_security;
 432         sb->s_security = NULL;
 433         kfree(sbsec);
 434 }
 435
 436 static inline int inode_doinit(struct inode *inode)
 437 {
 438         return inode_doinit_with_dentry(inode, NULL);
 439 }
 440
 441 enum {
 442         Opt_error = -1,
 443         Opt_context = 1,
 444         Opt_fscontext = 2,
 445         Opt_defcontext = 3,
 446         Opt_rootcontext = 4,
 447         Opt_labelsupport = 5,
 448         Opt_nextmntopt = 6,
 449 };
 450
 451 #define NUM_SEL_MNT_OPTS        (Opt_nextmntopt - 1)
 452
 453 static const match_table_t tokens = {
 454         {Opt_context, CONTEXT_STR "%s"},
 455         {Opt_fscontext, FSCONTEXT_STR "%s"},
 456         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 457         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 458         {Opt_labelsupport, LABELSUPP_STR},
 459         {Opt_error, NULL},
 460 };
 461
 462 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 463
 464 static int may_context_mount_sb_relabel(u32 sid,
 465                         struct superblock_security_struct *sbsec,
 466                         const struct cred *cred)
 467 {
 468         const struct task_security_struct *tsec = cred->security;
 469         int rc;
 470
 471         rc = avc_has_perm(&selinux_state,
 472                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 473                           FILESYSTEM__RELABELFROM, NULL);
 474         if (rc)
 475                 return rc;
 476
 477         rc = avc_has_perm(&selinux_state,
 478                           tsec->sid, sid, SECCLASS_FILESYSTEM,
 479                           FILESYSTEM__RELABELTO, NULL);
 480         return rc;
 481 }
 482
 483 static int may_context_mount_inode_relabel(u32 sid,
 484                         struct superblock_security_struct *sbsec,
 485                         const struct cred *cred)
 486 {
 487         const struct task_security_struct *tsec = cred->security;
 488         int rc;
 489         rc = avc_has_perm(&selinux_state,
 490                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 491                           FILESYSTEM__RELABELFROM, NULL);
 492         if (rc)
 493                 return rc;
 494
 495         rc = avc_has_perm(&selinux_state,
 496                           sid, sbsec->sid, SECCLASS_FILESYSTEM,
 497                           FILESYSTEM__ASSOCIATE, NULL);
 498         return rc;
 499 }
 500
 501 static int selinux_is_sblabel_mnt(struct super_block *sb)
 502 {
 503         struct superblock_security_struct *sbsec = sb->s_security;
 504
 505         return sbsec->behavior == SECURITY_FS_USE_XATTR ||
 506                 sbsec->behavior == SECURITY_FS_USE_TRANS ||
 507                 sbsec->behavior == SECURITY_FS_USE_TASK ||
 508                 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
 509                 /* Special handling. Genfs but also in-core setxattr handler */
 510                 !strcmp(sb->s_type->name, "sysfs") ||
 511                 !strcmp(sb->s_type->name, "pstore") ||
 512                 !strcmp(sb->s_type->name, "debugfs") ||
 513                 !strcmp(sb->s_type->name, "tracefs") ||
 514                 !strcmp(sb->s_type->name, "rootfs") ||
 515                 (selinux_policycap_cgroupseclabel() &&
 516                  (!strcmp(sb->s_type->name, "cgroup") ||
 517                   !strcmp(sb->s_type->name, "cgroup2")));
 518 }
 519
 520 static int sb_finish_set_opts(struct super_block *sb)
 521 {
 522         struct superblock_security_struct *sbsec = sb->s_security;
 523         struct dentry *root = sb->s_root;
 524         struct inode *root_inode = d_backing_inode(root);
 525         int rc = 0;
 526
 527         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 528                 /* Make sure that the xattr handler exists and that no
 529                    error other than -ENODATA is returned by getxattr on
 530                    the root directory.  -ENODATA is ok, as this may be
 531                    the first boot of the SELinux kernel before we have
 532                    assigned xattr values to the filesystem. */
 533                 if (!(root_inode->i_opflags & IOP_XATTR)) {
 534                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 535                                "xattr support\n", sb->s_id, sb->s_type->name);
 536                         rc = -EOPNOTSUPP;
 537                         goto out;
 538                 }
 539
 540                 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 541                 if (rc < 0 && rc != -ENODATA) {
 542                         if (rc == -EOPNOTSUPP)
 543                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 544                                        "%s) has no security xattr handler\n",
 545                                        sb->s_id, sb->s_type->name);
 546                         else
 547                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 548                                        "%s) getxattr errno %d\n", sb->s_id,
 549                                        sb->s_type->name, -rc);
 550                         goto out;
 551                 }
 552         }
 553
 554         sbsec->flags |= SE_SBINITIALIZED;
 555
 556         /*
 557          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 558          * leave the flag untouched because sb_clone_mnt_opts might be handing
 559          * us a superblock that needs the flag to be cleared.
 560          */
 561         if (selinux_is_sblabel_mnt(sb))
 562                 sbsec->flags |= SBLABEL_MNT;
 563         else
 564                 sbsec->flags &= ~SBLABEL_MNT;
 565
 566         /* Initialize the root inode. */
 567         rc = inode_doinit_with_dentry(root_inode, root);
 568
 569         /* Initialize any other inodes associated with the superblock, e.g.
 570            inodes created prior to initial policy load or inodes created
 571            during get_sb by a pseudo filesystem that directly
 572            populates itself. */
 573         spin_lock(&sbsec->isec_lock);
 574 next_inode:
 575         if (!list_empty(&sbsec->isec_head)) {
 576                 struct inode_security_struct *isec =
 577                                 list_entry(sbsec->isec_head.next,
 578                                            struct inode_security_struct, list);
 579                 struct inode *inode = isec->inode;
 580                 list_del_init(&isec->list);
 581                 spin_unlock(&sbsec->isec_lock);
 582                 inode = igrab(inode);
 583                 if (inode) {
 584                         if (!IS_PRIVATE(inode))
 585                                 inode_doinit(inode);
 586                         iput(inode);
 587                 }
 588                 spin_lock(&sbsec->isec_lock);
 589                 goto next_inode;
 590         }
 591         spin_unlock(&sbsec->isec_lock);
 592 out:
 593         return rc;
 594 }
 595
 596 /*
 597  * This function should allow an FS to ask what it's mount security
 598  * options were so it can use those later for submounts, displaying
 599  * mount options, or whatever.
 600  */
 601 static int selinux_get_mnt_opts(const struct super_block *sb,
 602                                 struct security_mnt_opts *opts)
 603 {
 604         int rc = 0, i;
 605         struct superblock_security_struct *sbsec = sb->s_security;
 606         char *context = NULL;
 607         u32 len;
 608         char tmp;
 609
 610         security_init_mnt_opts(opts);
 611
 612         if (!(sbsec->flags & SE_SBINITIALIZED))
 613                 return -EINVAL;
 614
 615         if (!selinux_state.initialized)
 616                 return -EINVAL;
 617
 618         /* make sure we always check enough bits to cover the mask */
 619         BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
 620
 621         tmp = sbsec->flags & SE_MNTMASK;
 622         /* count the number of mount options for this sb */
 623         for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
 624                 if (tmp & 0x01)
 625                         opts->num_mnt_opts++;
 626                 tmp >>= 1;
 627         }
 628         /* Check if the Label support flag is set */
 629         if (sbsec->flags & SBLABEL_MNT)
 630                 opts->num_mnt_opts++;
 631
 632         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 633         if (!opts->mnt_opts) {
 634                 rc = -ENOMEM;
 635                 goto out_free;
 636         }
 637
 638         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 639         if (!opts->mnt_opts_flags) {
 640                 rc = -ENOMEM;
 641                 goto out_free;
 642         }
 643
 644         i = 0;
 645         if (sbsec->flags & FSCONTEXT_MNT) {
 646                 rc = security_sid_to_context(&selinux_state, sbsec->sid,
 647                                              &context, &len);
 648                 if (rc)
 649                         goto out_free;
 650                 opts->mnt_opts[i] = context;
 651                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 652         }
 653         if (sbsec->flags & CONTEXT_MNT) {
 654                 rc = security_sid_to_context(&selinux_state,
 655                                              sbsec->mntpoint_sid,
 656                                              &context, &len);
 657                 if (rc)
 658                         goto out_free;
 659                 opts->mnt_opts[i] = context;
 660                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 661         }
 662         if (sbsec->flags & DEFCONTEXT_MNT) {
 663                 rc = security_sid_to_context(&selinux_state, sbsec->def_sid,
 664                                              &context, &len);
 665                 if (rc)
 666                         goto out_free;
 667                 opts->mnt_opts[i] = context;
 668                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 669         }
 670         if (sbsec->flags & ROOTCONTEXT_MNT) {
 671                 struct dentry *root = sbsec->sb->s_root;
 672                 struct inode_security_struct *isec = backing_inode_security(root);
 673
 674                 rc = security_sid_to_context(&selinux_state, isec->sid,
 675                                              &context, &len);
 676                 if (rc)
 677                         goto out_free;
 678                 opts->mnt_opts[i] = context;
 679                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 680         }
 681         if (sbsec->flags & SBLABEL_MNT) {
 682                 opts->mnt_opts[i] = NULL;
 683                 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
 684         }
 685
 686         BUG_ON(i != opts->num_mnt_opts);
 687
 688         return 0;
 689
 690 out_free:
 691         security_free_mnt_opts(opts);
 692         return rc;
 693 }
 694
 695 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 696                       u32 old_sid, u32 new_sid)
 697 {
 698         char mnt_flags = sbsec->flags & SE_MNTMASK;
 699
 700         /* check if the old mount command had the same options */
 701         if (sbsec->flags & SE_SBINITIALIZED)
 702                 if (!(sbsec->flags & flag) ||
 703                     (old_sid != new_sid))
 704                         return 1;
 705
 706         /* check if we were passed the same options twice,
 707          * aka someone passed context=a,context=b
 708          */
 709         if (!(sbsec->flags & SE_SBINITIALIZED))
 710                 if (mnt_flags & flag)
 711                         return 1;
 712         return 0;
 713 }
 714
 715 /*
 716  * Allow filesystems with binary mount data to explicitly set mount point
 717  * labeling information.
 718  */
 719 static int selinux_set_mnt_opts(struct super_block *sb,
 720                                 struct security_mnt_opts *opts,
 721                                 unsigned long kern_flags,
 722                                 unsigned long *set_kern_flags)
 723 {
 724         const struct cred *cred = current_cred();
 725         int rc = 0, i;
 726         struct superblock_security_struct *sbsec = sb->s_security;
 727         const char *name = sb->s_type->name;
 728         struct dentry *root = sbsec->sb->s_root;
 729         struct inode_security_struct *root_isec;
 730         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 731         u32 defcontext_sid = 0;
 732         char **mount_options = opts->mnt_opts;
 733         int *flags = opts->mnt_opts_flags;
 734         int num_opts = opts->num_mnt_opts;
 735
 736         mutex_lock(&sbsec->lock);
 737
 738         if (!selinux_state.initialized) {
 739                 if (!num_opts) {
 740                         /* Defer initialization until selinux_complete_init,
 741                            after the initial policy is loaded and the security
 742                            server is ready to handle calls. */
 743                         goto out;
 744                 }
 745                 rc = -EINVAL;
 746                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 747                         "before the security server is initialized\n");
 748                 goto out;
 749         }
 750         if (kern_flags && !set_kern_flags) {
 751                 /* Specifying internal flags without providing a place to
 752                  * place the results is not allowed */
 753                 rc = -EINVAL;
 754                 goto out;
 755         }
 756
 757         /*
 758          * Binary mount data FS will come through this function twice.  Once
 759          * from an explicit call and once from the generic calls from the vfs.
 760          * Since the generic VFS calls will not contain any security mount data
 761          * we need to skip the double mount verification.
 762          *
 763          * This does open a hole in which we will not notice if the first
 764          * mount using this sb set explict options and a second mount using
 765          * this sb does not set any security options.  (The first options
 766          * will be used for both mounts)
 767          */
 768         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 769             && (num_opts == 0))
 770                 goto out;
 771
 772         root_isec = backing_inode_security_novalidate(root);
 773
 774         /*
 775          * parse the mount options, check if they are valid sids.
 776          * also check if someone is trying to mount the same sb more
 777          * than once with different security options.
 778          */
 779         for (i = 0; i < num_opts; i++) {
 780                 u32 sid;
 781
 782                 if (flags[i] == SBLABEL_MNT)
 783                         continue;
 784                 rc = security_context_str_to_sid(&selinux_state,
 785                                                  mount_options[i], &sid,
 786                                                  GFP_KERNEL);
 787                 if (rc) {
 788                         printk(KERN_WARNING "SELinux: security_context_str_to_sid"
 789                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 790                                mount_options[i], sb->s_id, name, rc);
 791                         goto out;
 792                 }
 793                 switch (flags[i]) {
 794                 case FSCONTEXT_MNT:
 795                         fscontext_sid = sid;
 796
 797                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 798                                         fscontext_sid))
 799                                 goto out_double_mount;
 800
 801                         sbsec->flags |= FSCONTEXT_MNT;
 802                         break;
 803                 case CONTEXT_MNT:
 804                         context_sid = sid;
 805
 806                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 807                                         context_sid))
 808                                 goto out_double_mount;
 809
 810                         sbsec->flags |= CONTEXT_MNT;
 811                         break;
 812                 case ROOTCONTEXT_MNT:
 813                         rootcontext_sid = sid;
 814
 815                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 816                                         rootcontext_sid))
 817                                 goto out_double_mount;
 818
 819                         sbsec->flags |= ROOTCONTEXT_MNT;
 820
 821                         break;
 822                 case DEFCONTEXT_MNT:
 823                         defcontext_sid = sid;
 824
 825                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 826                                         defcontext_sid))
 827                                 goto out_double_mount;
 828
 829                         sbsec->flags |= DEFCONTEXT_MNT;
 830
 831                         break;
 832                 default:
 833                         rc = -EINVAL;
 834                         goto out;
 835                 }
 836         }
 837
 838         if (sbsec->flags & SE_SBINITIALIZED) {
 839                 /* previously mounted with options, but not on this attempt? */
 840                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 841                         goto out_double_mount;
 842                 rc = 0;
 843                 goto out;
 844         }
 845
 846         if (strcmp(sb->s_type->name, "proc") == 0)
 847                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 848
 849         if (!strcmp(sb->s_type->name, "debugfs") ||
 850             !strcmp(sb->s_type->name, "tracefs") ||
 851             !strcmp(sb->s_type->name, "sysfs") ||
 852             !strcmp(sb->s_type->name, "pstore") ||
 853             !strcmp(sb->s_type->name, "cgroup") ||
 854             !strcmp(sb->s_type->name, "cgroup2"))
 855                 sbsec->flags |= SE_SBGENFS;
 856
 857         if (!sbsec->behavior) {
 858                 /*
 859                  * Determine the labeling behavior to use for this
 860                  * filesystem type.
 861                  */
 862                 rc = security_fs_use(&selinux_state, sb);
 863                 if (rc) {
 864                         printk(KERN_WARNING
 865                                 "%s: security_fs_use(%s) returned %d\n",
 866                                         __func__, sb->s_type->name, rc);
 867                         goto out;
 868                 }
 869         }
 870
 871         /*
 872          * If this is a user namespace mount and the filesystem type is not
 873          * explicitly whitelisted, then no contexts are allowed on the command
 874          * line and security labels must be ignored.
 875          */
 876         if (sb->s_user_ns != &init_user_ns &&
 877             strcmp(sb->s_type->name, "tmpfs") &&
 878             strcmp(sb->s_type->name, "ramfs") &&
 879             strcmp(sb->s_type->name, "devpts")) {
 880                 if (context_sid || fscontext_sid || rootcontext_sid ||
 881                     defcontext_sid) {
 882                         rc = -EACCES;
 883                         goto out;
 884                 }
 885                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 886                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 887                         rc = security_transition_sid(&selinux_state,
 888                                                      current_sid(),
 889                                                      current_sid(),
 890                                                      SECCLASS_FILE, NULL,
 891                                                      &sbsec->mntpoint_sid);
 892                         if (rc)
 893                                 goto out;
 894                 }
 895                 goto out_set_opts;
 896         }
 897
 898         /* sets the context of the superblock for the fs being mounted. */
 899         if (fscontext_sid) {
 900                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 901                 if (rc)
 902                         goto out;
 903
 904                 sbsec->sid = fscontext_sid;
 905         }
 906
 907         /*
 908          * Switch to using mount point labeling behavior.
 909          * sets the label used on all file below the mountpoint, and will set
 910          * the superblock context if not already set.
 911          */
 912         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 913                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 914                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 915         }
 916
 917         if (context_sid) {
 918                 if (!fscontext_sid) {
 919                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 920                                                           cred);
 921                         if (rc)
 922                                 goto out;
 923                         sbsec->sid = context_sid;
 924                 } else {
 925                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 926                                                              cred);
 927                         if (rc)
 928                                 goto out;
 929                 }
 930                 if (!rootcontext_sid)
 931                         rootcontext_sid = context_sid;
 932
 933                 sbsec->mntpoint_sid = context_sid;
 934                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 935         }
 936
 937         if (rootcontext_sid) {
 938                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 939                                                      cred);
 940                 if (rc)
 941                         goto out;
 942
 943                 root_isec->sid = rootcontext_sid;
 944                 root_isec->initialized = LABEL_INITIALIZED;
 945         }
 946
 947         if (defcontext_sid) {
 948                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 949                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 950                         rc = -EINVAL;
 951                         printk(KERN_WARNING "SELinux: defcontext option is "
 952                                "invalid for this filesystem type\n");
 953                         goto out;
 954                 }
 955
 956                 if (defcontext_sid != sbsec->def_sid) {
 957                         rc = may_context_mount_inode_relabel(defcontext_sid,
 958                                                              sbsec, cred);
 959                         if (rc)
 960                                 goto out;
 961                 }
 962
 963                 sbsec->def_sid = defcontext_sid;
 964         }
 965
 966 out_set_opts:
 967         rc = sb_finish_set_opts(sb);
 968 out:
 969         mutex_unlock(&sbsec->lock);
 970         return rc;
 971 out_double_mount:
 972         rc = -EINVAL;
 973         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 974                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 975         goto out;
 976 }
 977
 978 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 979                                     const struct super_block *newsb)
 980 {
 981         struct superblock_security_struct *old = oldsb->s_security;
 982         struct superblock_security_struct *new = newsb->s_security;
 983         char oldflags = old->flags & SE_MNTMASK;
 984         char newflags = new->flags & SE_MNTMASK;
 985
 986         if (oldflags != newflags)
 987                 goto mismatch;
 988         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 989                 goto mismatch;
 990         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 991                 goto mismatch;
 992         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 993                 goto mismatch;
 994         if (oldflags & ROOTCONTEXT_MNT) {
 995                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 996                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 997                 if (oldroot->sid != newroot->sid)
 998                         goto mismatch;
 999         }
1000         return 0;
1001 mismatch:
1002         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
1003                             "different security settings for (dev %s, "
1004                             "type %s)\n", newsb->s_id, newsb->s_type->name);
1005         return -EBUSY;
1006 }
1007
1008 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
1009                                         struct super_block *newsb,
1010                                         unsigned long kern_flags,
1011                                         unsigned long *set_kern_flags)
1012 {
1013         int rc = 0;
1014         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
1015         struct superblock_security_struct *newsbsec = newsb->s_security;
1016
1017         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
1018         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
1019         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
1020
1021         /*
1022          * if the parent was able to be mounted it clearly had no special lsm
1023          * mount options.  thus we can safely deal with this superblock later
1024          */
1025         if (!selinux_state.initialized)
1026                 return 0;
1027
1028         /*
1029          * Specifying internal flags without providing a place to
1030          * place the results is not allowed.
1031          */
1032         if (kern_flags && !set_kern_flags)
1033                 return -EINVAL;
1034
1035         /* how can we clone if the old one wasn't set up?? */
1036         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
1037
1038         /* if fs is reusing a sb, make sure that the contexts match */
1039         if (newsbsec->flags & SE_SBINITIALIZED)
1040                 return selinux_cmp_sb_context(oldsb, newsb);
1041
1042         mutex_lock(&newsbsec->lock);
1043
1044         newsbsec->flags = oldsbsec->flags;
1045
1046         newsbsec->sid = oldsbsec->sid;
1047         newsbsec->def_sid = oldsbsec->def_sid;
1048         newsbsec->behavior = oldsbsec->behavior;
1049
1050         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
1051                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
1052                 rc = security_fs_use(&selinux_state, newsb);
1053                 if (rc)
1054                         goto out;
1055         }
1056
1057         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
1058                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
1059                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
1060         }
1061
1062         if (set_context) {
1063                 u32 sid = oldsbsec->mntpoint_sid;
1064
1065                 if (!set_fscontext)
1066                         newsbsec->sid = sid;
1067                 if (!set_rootcontext) {
1068                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1069                         newisec->sid = sid;
1070                 }
1071                 newsbsec->mntpoint_sid = sid;
1072         }
1073         if (set_rootcontext) {
1074                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
1075                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1076
1077                 newisec->sid = oldisec->sid;
1078         }
1079
1080         sb_finish_set_opts(newsb);
1081 out:
1082         mutex_unlock(&newsbsec->lock);
1083         return rc;
1084 }
1085
1086 static int selinux_parse_opts_str(char *options,
1087                                   struct security_mnt_opts *opts)
1088 {
1089         char *p;
1090         char *context = NULL, *defcontext = NULL;
1091         char *fscontext = NULL, *rootcontext = NULL;
1092         int rc, num_mnt_opts = 0;
1093
1094         opts->num_mnt_opts = 0;
1095
1096         /* Standard string-based options. */
1097         while ((p = strsep(&options, "|")) != NULL) {
1098                 int token;
1099                 substring_t args[MAX_OPT_ARGS];
1100
1101                 if (!*p)
1102                         continue;
1103
1104                 token = match_token(p, tokens, args);
1105
1106                 switch (token) {
1107                 case Opt_context:
1108                         if (context || defcontext) {
1109                                 rc = -EINVAL;
1110                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1111                                 goto out_err;
1112                         }
1113                         context = match_strdup(&args[0]);
1114                         if (!context) {
1115                                 rc = -ENOMEM;
1116                                 goto out_err;
1117                         }
1118                         break;
1119
1120                 case Opt_fscontext:
1121                         if (fscontext) {
1122                                 rc = -EINVAL;
1123                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1124                                 goto out_err;
1125                         }
1126                         fscontext = match_strdup(&args[0]);
1127                         if (!fscontext) {
1128                                 rc = -ENOMEM;
1129                                 goto out_err;
1130                         }
1131                         break;
1132
1133                 case Opt_rootcontext:
1134                         if (rootcontext) {
1135                                 rc = -EINVAL;
1136                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1137                                 goto out_err;
1138                         }
1139                         rootcontext = match_strdup(&args[0]);
1140                         if (!rootcontext) {
1141                                 rc = -ENOMEM;
1142                                 goto out_err;
1143                         }
1144                         break;
1145
1146                 case Opt_defcontext:
1147                         if (context || defcontext) {
1148                                 rc = -EINVAL;
1149                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1150                                 goto out_err;
1151                         }
1152                         defcontext = match_strdup(&args[0]);
1153                         if (!defcontext) {
1154                                 rc = -ENOMEM;
1155                                 goto out_err;
1156                         }
1157                         break;
1158                 case Opt_labelsupport:
1159                         break;
1160                 default:
1161                         rc = -EINVAL;
1162                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
1163                         goto out_err;
1164
1165                 }
1166         }
1167
1168         rc = -ENOMEM;
1169         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1170         if (!opts->mnt_opts)
1171                 goto out_err;
1172
1173         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
1174                                        GFP_KERNEL);
1175         if (!opts->mnt_opts_flags)
1176                 goto out_err;
1177
1178         if (fscontext) {
1179                 opts->mnt_opts[num_mnt_opts] = fscontext;
1180                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1181         }
1182         if (context) {
1183                 opts->mnt_opts[num_mnt_opts] = context;
1184                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1185         }
1186         if (rootcontext) {
1187                 opts->mnt_opts[num_mnt_opts] = rootcontext;
1188                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1189         }
1190         if (defcontext) {
1191                 opts->mnt_opts[num_mnt_opts] = defcontext;
1192                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1193         }
1194
1195         opts->num_mnt_opts = num_mnt_opts;
1196         return 0;
1197
1198 out_err:
1199         security_free_mnt_opts(opts);
1200         kfree(context);
1201         kfree(defcontext);
1202         kfree(fscontext);
1203         kfree(rootcontext);
1204         return rc;
1205 }
1206 /*
1207  * string mount options parsing and call set the sbsec
1208  */
1209 static int superblock_doinit(struct super_block *sb, void *data)
1210 {
1211         int rc = 0;
1212         char *options = data;
1213         struct security_mnt_opts opts;
1214
1215         security_init_mnt_opts(&opts);
1216
1217         if (!data)
1218                 goto out;
1219
1220         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1221
1222         rc = selinux_parse_opts_str(options, &opts);
1223         if (rc)
1224                 goto out_err;
1225
1226 out:
1227         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1228
1229 out_err:
1230         security_free_mnt_opts(&opts);
1231         return rc;
1232 }
1233
1234 static void selinux_write_opts(struct seq_file *m,
1235                                struct security_mnt_opts *opts)
1236 {
1237         int i;
1238         char *prefix;
1239
1240         for (i = 0; i < opts->num_mnt_opts; i++) {
1241                 char *has_comma;
1242
1243                 if (opts->mnt_opts[i])
1244                         has_comma = strchr(opts->mnt_opts[i], ',');
1245                 else
1246                         has_comma = NULL;
1247
1248                 switch (opts->mnt_opts_flags[i]) {
1249                 case CONTEXT_MNT:
1250                         prefix = CONTEXT_STR;
1251                         break;
1252                 case FSCONTEXT_MNT:
1253                         prefix = FSCONTEXT_STR;
1254                         break;
1255                 case ROOTCONTEXT_MNT:
1256                         prefix = ROOTCONTEXT_STR;
1257                         break;
1258                 case DEFCONTEXT_MNT:
1259                         prefix = DEFCONTEXT_STR;
1260                         break;
1261                 case SBLABEL_MNT:
1262                         seq_putc(m, ',');
1263                         seq_puts(m, LABELSUPP_STR);
1264                         continue;
1265                 default:
1266                         BUG();
1267                         return;
1268                 };
1269                 /* we need a comma before each option */
1270                 seq_putc(m, ',');
1271                 seq_puts(m, prefix);
1272                 if (has_comma)
1273                         seq_putc(m, '\"');
1274                 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1275                 if (has_comma)
1276                         seq_putc(m, '\"');
1277         }
1278 }
1279
1280 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1281 {
1282         struct security_mnt_opts opts;
1283         int rc;
1284
1285         rc = selinux_get_mnt_opts(sb, &opts);
1286         if (rc) {
1287                 /* before policy load we may get EINVAL, don't show anything */
1288                 if (rc == -EINVAL)
1289                         rc = 0;
1290                 return rc;
1291         }
1292
1293         selinux_write_opts(m, &opts);
1294
1295         security_free_mnt_opts(&opts);
1296
1297         return rc;
1298 }
1299
1300 static inline u16 inode_mode_to_security_class(umode_t mode)
1301 {
1302         switch (mode & S_IFMT) {
1303         case S_IFSOCK:
1304                 return SECCLASS_SOCK_FILE;
1305         case S_IFLNK:
1306                 return SECCLASS_LNK_FILE;
1307         case S_IFREG:
1308                 return SECCLASS_FILE;
1309         case S_IFBLK:
1310                 return SECCLASS_BLK_FILE;
1311         case S_IFDIR:
1312                 return SECCLASS_DIR;
1313         case S_IFCHR:
1314                 return SECCLASS_CHR_FILE;
1315         case S_IFIFO:
1316                 return SECCLASS_FIFO_FILE;
1317
1318         }
1319
1320         return SECCLASS_FILE;
1321 }
1322
1323 static inline int default_protocol_stream(int protocol)
1324 {
1325         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1326 }
1327
1328 static inline int default_protocol_dgram(int protocol)
1329 {
1330         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1331 }
1332
1333 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1334 {
1335         int extsockclass = selinux_policycap_extsockclass();
1336
1337         switch (family) {
1338         case PF_UNIX:
1339                 switch (type) {
1340                 case SOCK_STREAM:
1341                 case SOCK_SEQPACKET:
1342                         return SECCLASS_UNIX_STREAM_SOCKET;
1343                 case SOCK_DGRAM:
1344                 case SOCK_RAW:
1345                         return SECCLASS_UNIX_DGRAM_SOCKET;
1346                 }
1347                 break;
1348         case PF_INET:
1349         case PF_INET6:
1350                 switch (type) {
1351                 case SOCK_STREAM:
1352                 case SOCK_SEQPACKET:
1353                         if (default_protocol_stream(protocol))
1354                                 return SECCLASS_TCP_SOCKET;
1355                         else if (extsockclass && protocol == IPPROTO_SCTP)
1356                                 return SECCLASS_SCTP_SOCKET;
1357                         else
1358                                 return SECCLASS_RAWIP_SOCKET;
1359                 case SOCK_DGRAM:
1360                         if (default_protocol_dgram(protocol))
1361                                 return SECCLASS_UDP_SOCKET;
1362                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1363                                                   protocol == IPPROTO_ICMPV6))
1364                                 return SECCLASS_ICMP_SOCKET;
1365                         else
1366                                 return SECCLASS_RAWIP_SOCKET;
1367                 case SOCK_DCCP:
1368                         return SECCLASS_DCCP_SOCKET;
1369                 default:
1370                         return SECCLASS_RAWIP_SOCKET;
1371                 }
1372                 break;
1373         case PF_NETLINK:
1374                 switch (protocol) {
1375                 case NETLINK_ROUTE:
1376                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1377                 case NETLINK_SOCK_DIAG:
1378                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1379                 case NETLINK_NFLOG:
1380                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1381                 case NETLINK_XFRM:
1382                         return SECCLASS_NETLINK_XFRM_SOCKET;
1383                 case NETLINK_SELINUX:
1384                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1385                 case NETLINK_ISCSI:
1386                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1387                 case NETLINK_AUDIT:
1388                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1389                 case NETLINK_FIB_LOOKUP:
1390                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1391                 case NETLINK_CONNECTOR:
1392                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1393                 case NETLINK_NETFILTER:
1394                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1395                 case NETLINK_DNRTMSG:
1396                         return SECCLASS_NETLINK_DNRT_SOCKET;
1397                 case NETLINK_KOBJECT_UEVENT:
1398                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1399                 case NETLINK_GENERIC:
1400                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1401                 case NETLINK_SCSITRANSPORT:
1402                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1403                 case NETLINK_RDMA:
1404                         return SECCLASS_NETLINK_RDMA_SOCKET;
1405                 case NETLINK_CRYPTO:
1406                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1407                 default:
1408                         return SECCLASS_NETLINK_SOCKET;
1409                 }
1410         case PF_PACKET:
1411                 return SECCLASS_PACKET_SOCKET;
1412         case PF_KEY:
1413                 return SECCLASS_KEY_SOCKET;
1414         case PF_APPLETALK:
1415                 return SECCLASS_APPLETALK_SOCKET;
1416         }
1417
1418         if (extsockclass) {
1419                 switch (family) {
1420                 case PF_AX25:
1421                         return SECCLASS_AX25_SOCKET;
1422                 case PF_IPX:
1423                         return SECCLASS_IPX_SOCKET;
1424                 case PF_NETROM:
1425                         return SECCLASS_NETROM_SOCKET;
1426                 case PF_ATMPVC:
1427                         return SECCLASS_ATMPVC_SOCKET;
1428                 case PF_X25:
1429                         return SECCLASS_X25_SOCKET;
1430                 case PF_ROSE:
1431                         return SECCLASS_ROSE_SOCKET;
1432                 case PF_DECnet:
1433                         return SECCLASS_DECNET_SOCKET;
1434                 case PF_ATMSVC:
1435                         return SECCLASS_ATMSVC_SOCKET;
1436                 case PF_RDS:
1437                         return SECCLASS_RDS_SOCKET;
1438                 case PF_IRDA:
1439                         return SECCLASS_IRDA_SOCKET;
1440                 case PF_PPPOX:
1441                         return SECCLASS_PPPOX_SOCKET;
1442                 case PF_LLC:
1443                         return SECCLASS_LLC_SOCKET;
1444                 case PF_CAN:
1445                         return SECCLASS_CAN_SOCKET;
1446                 case PF_TIPC:
1447                         return SECCLASS_TIPC_SOCKET;
1448                 case PF_BLUETOOTH:
1449                         return SECCLASS_BLUETOOTH_SOCKET;
1450                 case PF_IUCV:
1451                         return SECCLASS_IUCV_SOCKET;
1452                 case PF_RXRPC:
1453                         return SECCLASS_RXRPC_SOCKET;
1454                 case PF_ISDN:
1455                         return SECCLASS_ISDN_SOCKET;
1456                 case PF_PHONET:
1457                         return SECCLASS_PHONET_SOCKET;
1458                 case PF_IEEE802154:
1459                         return SECCLASS_IEEE802154_SOCKET;
1460                 case PF_CAIF:
1461                         return SECCLASS_CAIF_SOCKET;
1462                 case PF_ALG:
1463                         return SECCLASS_ALG_SOCKET;
1464                 case PF_NFC:
1465                         return SECCLASS_NFC_SOCKET;
1466                 case PF_VSOCK:
1467                         return SECCLASS_VSOCK_SOCKET;
1468                 case PF_KCM:
1469                         return SECCLASS_KCM_SOCKET;
1470                 case PF_QIPCRTR:
1471                         return SECCLASS_QIPCRTR_SOCKET;
1472                 case PF_SMC:
1473                         return SECCLASS_SMC_SOCKET;
1474                 case PF_XDP:
1475                         return SECCLASS_XDP_SOCKET;
1476 #if PF_MAX > 45
1477 #error New address family defined, please update this function.
1478 #endif
1479                 }
1480         }
1481
1482         return SECCLASS_SOCKET;
1483 }
1484
1485 static int selinux_genfs_get_sid(struct dentry *dentry,
1486                                  u16 tclass,
1487                                  u16 flags,
1488                                  u32 *sid)
1489 {
1490         int rc;
1491         struct super_block *sb = dentry->d_sb;
1492         char *buffer, *path;
1493
1494         buffer = (char *)__get_free_page(GFP_KERNEL);
1495         if (!buffer)
1496                 return -ENOMEM;
1497
1498         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1499         if (IS_ERR(path))
1500                 rc = PTR_ERR(path);
1501         else {
1502                 if (flags & SE_SBPROC) {
1503                         /* each process gets a /proc/PID/ entry. Strip off the
1504                          * PID part to get a valid selinux labeling.
1505                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1506                         while (path[1] >= '0' && path[1] <= '9') {
1507                                 path[1] = '/';
1508                                 path++;
1509                         }
1510                 }
1511                 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1512                                         path, tclass, sid);
1513         }
1514         free_page((unsigned long)buffer);
1515         return rc;
1516 }
1517
1518 /* The inode's security attributes must be initialized before first use. */
1519 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1520 {
1521         struct superblock_security_struct *sbsec = NULL;
1522         struct inode_security_struct *isec = inode->i_security;
1523         u32 task_sid, sid = 0;
1524         u16 sclass;
1525         struct dentry *dentry;
1526 #define INITCONTEXTLEN 255
1527         char *context = NULL;
1528         unsigned len = 0;
1529         int rc = 0;
1530
1531         if (isec->initialized == LABEL_INITIALIZED)
1532                 return 0;
1533
1534         spin_lock(&isec->lock);
1535         if (isec->initialized == LABEL_INITIALIZED)
1536                 goto out_unlock;
1537
1538         if (isec->sclass == SECCLASS_FILE)
1539                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1540
1541         sbsec = inode->i_sb->s_security;
1542         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1543                 /* Defer initialization until selinux_complete_init,
1544                    after the initial policy is loaded and the security
1545                    server is ready to handle calls. */
1546                 spin_lock(&sbsec->isec_lock);
1547                 if (list_empty(&isec->list))
1548                         list_add(&isec->list, &sbsec->isec_head);
1549                 spin_unlock(&sbsec->isec_lock);
1550                 goto out_unlock;
1551         }
1552
1553         sclass = isec->sclass;
1554         task_sid = isec->task_sid;
1555         sid = isec->sid;
1556         isec->initialized = LABEL_PENDING;
1557         spin_unlock(&isec->lock);
1558
1559         switch (sbsec->behavior) {
1560         case SECURITY_FS_USE_NATIVE:
1561                 break;
1562         case SECURITY_FS_USE_XATTR:
1563                 if (!(inode->i_opflags & IOP_XATTR)) {
1564                         sid = sbsec->def_sid;
1565                         break;
1566                 }
1567                 /* Need a dentry, since the xattr API requires one.
1568                    Life would be simpler if we could just pass the inode. */
1569                 if (opt_dentry) {
1570                         /* Called from d_instantiate or d_splice_alias. */
1571                         dentry = dget(opt_dentry);
1572                 } else {
1573                         /* Called from selinux_complete_init, try to find a dentry. */
1574                         dentry = d_find_alias(inode);
1575                 }
1576                 if (!dentry) {
1577                         /*
1578                          * this is can be hit on boot when a file is accessed
1579                          * before the policy is loaded.  When we load policy we
1580                          * may find inodes that have no dentry on the
1581                          * sbsec->isec_head list.  No reason to complain as these
1582                          * will get fixed up the next time we go through
1583                          * inode_doinit with a dentry, before these inodes could
1584                          * be used again by userspace.
1585                          */
1586                         goto out;
1587                 }
1588
1589                 len = INITCONTEXTLEN;
1590                 context = kmalloc(len+1, GFP_NOFS);
1591                 if (!context) {
1592                         rc = -ENOMEM;
1593                         dput(dentry);
1594                         goto out;
1595                 }
1596                 context[len] = '\0';
1597                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1598                 if (rc == -ERANGE) {
1599                         kfree(context);
1600
1601                         /* Need a larger buffer.  Query for the right size. */
1602                         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1603                         if (rc < 0) {
1604                                 dput(dentry);
1605                                 goto out;
1606                         }
1607                         len = rc;
1608                         context = kmalloc(len+1, GFP_NOFS);
1609                         if (!context) {
1610                                 rc = -ENOMEM;
1611                                 dput(dentry);
1612                                 goto out;
1613                         }
1614                         context[len] = '\0';
1615                         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1616                 }
1617                 dput(dentry);
1618                 if (rc < 0) {
1619                         if (rc != -ENODATA) {
1620                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1621                                        "%d for dev=%s ino=%ld\n", __func__,
1622                                        -rc, inode->i_sb->s_id, inode->i_ino);
1623                                 kfree(context);
1624                                 goto out;
1625                         }
1626                         /* Map ENODATA to the default file SID */
1627                         sid = sbsec->def_sid;
1628                         rc = 0;
1629                 } else {
1630                         rc = security_context_to_sid_default(&selinux_state,
1631                                                              context, rc, &sid,
1632                                                              sbsec->def_sid,
1633                                                              GFP_NOFS);
1634                         if (rc) {
1635                                 char *dev = inode->i_sb->s_id;
1636                                 unsigned long ino = inode->i_ino;
1637
1638                                 if (rc == -EINVAL) {
1639                                         if (printk_ratelimit())
1640                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1641                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1642                                                         "filesystem in question.\n", ino, dev, context);
1643                                 } else {
1644                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1645                                                "returned %d for dev=%s ino=%ld\n",
1646                                                __func__, context, -rc, dev, ino);
1647                                 }
1648                                 kfree(context);
1649                                 /* Leave with the unlabeled SID */
1650                                 rc = 0;
1651                                 break;
1652                         }
1653                 }
1654                 kfree(context);
1655                 break;
1656         case SECURITY_FS_USE_TASK:
1657                 sid = task_sid;
1658                 break;
1659         case SECURITY_FS_USE_TRANS:
1660                 /* Default to the fs SID. */
1661                 sid = sbsec->sid;
1662
1663                 /* Try to obtain a transition SID. */
1664                 rc = security_transition_sid(&selinux_state, task_sid, sid,
1665                                              sclass, NULL, &sid);
1666                 if (rc)
1667                         goto out;
1668                 break;
1669         case SECURITY_FS_USE_MNTPOINT:
1670                 sid = sbsec->mntpoint_sid;
1671                 break;
1672         default:
1673                 /* Default to the fs superblock SID. */
1674                 sid = sbsec->sid;
1675
1676                 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1677                         /* We must have a dentry to determine the label on
1678                          * procfs inodes */
1679                         if (opt_dentry)
1680                                 /* Called from d_instantiate or
1681                                  * d_splice_alias. */
1682                                 dentry = dget(opt_dentry);
1683                         else
1684                                 /* Called from selinux_complete_init, try to
1685                                  * find a dentry. */
1686                                 dentry = d_find_alias(inode);
1687                         /*
1688                          * This can be hit on boot when a file is accessed
1689                          * before the policy is loaded.  When we load policy we
1690                          * may find inodes that have no dentry on the
1691                          * sbsec->isec_head list.  No reason to complain as
1692                          * these will get fixed up the next time we go through
1693                          * inode_doinit() with a dentry, before these inodes
1694                          * could be used again by userspace.
1695                          */
1696                         if (!dentry)
1697                                 goto out;
1698                         rc = selinux_genfs_get_sid(dentry, sclass,
1699                                                    sbsec->flags, &sid);
1700                         dput(dentry);
1701                         if (rc)
1702                                 goto out;
1703                 }
1704                 break;
1705         }
1706
1707 out:
1708         spin_lock(&isec->lock);
1709         if (isec->initialized == LABEL_PENDING) {
1710                 if (!sid || rc) {
1711                         isec->initialized = LABEL_INVALID;
1712                         goto out_unlock;
1713                 }
1714
1715                 isec->initialized = LABEL_INITIALIZED;
1716                 isec->sid = sid;
1717         }
1718
1719 out_unlock:
1720         spin_unlock(&isec->lock);
1721         return rc;
1722 }
1723
1724 /* Convert a Linux signal to an access vector. */
1725 static inline u32 signal_to_av(int sig)
1726 {
1727         u32 perm = 0;
1728
1729         switch (sig) {
1730         case SIGCHLD:
1731                 /* Commonly granted from child to parent. */
1732                 perm = PROCESS__SIGCHLD;
1733                 break;
1734         case SIGKILL:
1735                 /* Cannot be caught or ignored */
1736                 perm = PROCESS__SIGKILL;
1737                 break;
1738         case SIGSTOP:
1739                 /* Cannot be caught or ignored */
1740                 perm = PROCESS__SIGSTOP;
1741                 break;
1742         default:
1743                 /* All other signals. */
1744                 perm = PROCESS__SIGNAL;
1745                 break;
1746         }
1747
1748         return perm;
1749 }
1750
1751 #if CAP_LAST_CAP > 63
1752 #error Fix SELinux to handle capabilities > 63.
1753 #endif
1754
1755 /* Check whether a task is allowed to use a capability. */
1756 static int cred_has_capability(const struct cred *cred,
1757                                int cap, int audit, bool initns)
1758 {
1759         struct common_audit_data ad;
1760         struct av_decision avd;
1761         u16 sclass;
1762         u32 sid = cred_sid(cred);
1763         u32 av = CAP_TO_MASK(cap);
1764         int rc;
1765
1766         ad.type = LSM_AUDIT_DATA_CAP;
1767         ad.u.cap = cap;
1768
1769         switch (CAP_TO_INDEX(cap)) {
1770         case 0:
1771                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1772                 break;
1773         case 1:
1774                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1775                 break;
1776         default:
1777                 printk(KERN_ERR
1778                        "SELinux:  out of range capability %d\n", cap);
1779                 BUG();
1780                 return -EINVAL;
1781         }
1782
1783         rc = avc_has_perm_noaudit(&selinux_state,
1784                                   sid, sid, sclass, av, 0, &avd);
1785         if (audit == SECURITY_CAP_AUDIT) {
1786                 int rc2 = avc_audit(&selinux_state,
1787                                     sid, sid, sclass, av, &avd, rc, &ad, 0);
1788                 if (rc2)
1789                         return rc2;
1790         }
1791         return rc;
1792 }
1793
1794 /* Check whether a task has a particular permission to an inode.
1795    The 'adp' parameter is optional and allows other audit
1796    data to be passed (e.g. the dentry). */
1797 static int inode_has_perm(const struct cred *cred,
1798                           struct inode *inode,
1799                           u32 perms,
1800                           struct common_audit_data *adp)
1801 {
1802         struct inode_security_struct *isec;
1803         u32 sid;
1804
1805         validate_creds(cred);
1806
1807         if (unlikely(IS_PRIVATE(inode)))
1808                 return 0;
1809
1810         sid = cred_sid(cred);
1811         isec = inode->i_security;
1812
1813         return avc_has_perm(&selinux_state,
1814                             sid, isec->sid, isec->sclass, perms, adp);
1815 }
1816
1817 /* Same as inode_has_perm, but pass explicit audit data containing
1818    the dentry to help the auditing code to more easily generate the
1819    pathname if needed. */
1820 static inline int dentry_has_perm(const struct cred *cred,
1821                                   struct dentry *dentry,
1822                                   u32 av)
1823 {
1824         struct inode *inode = d_backing_inode(dentry);
1825         struct common_audit_data ad;
1826
1827         ad.type = LSM_AUDIT_DATA_DENTRY;
1828         ad.u.dentry = dentry;
1829         __inode_security_revalidate(inode, dentry, true);
1830         return inode_has_perm(cred, inode, av, &ad);
1831 }
1832
1833 /* Same as inode_has_perm, but pass explicit audit data containing
1834    the path to help the auditing code to more easily generate the
1835    pathname if needed. */
1836 static inline int path_has_perm(const struct cred *cred,
1837                                 const struct path *path,
1838                                 u32 av)
1839 {
1840         struct inode *inode = d_backing_inode(path->dentry);
1841         struct common_audit_data ad;
1842
1843         ad.type = LSM_AUDIT_DATA_PATH;
1844         ad.u.path = *path;
1845         __inode_security_revalidate(inode, path->dentry, true);
1846         return inode_has_perm(cred, inode, av, &ad);
1847 }
1848
1849 /* Same as path_has_perm, but uses the inode from the file struct. */
1850 static inline int file_path_has_perm(const struct cred *cred,
1851                                      struct file *file,
1852                                      u32 av)
1853 {
1854         struct common_audit_data ad;
1855
1856         ad.type = LSM_AUDIT_DATA_FILE;
1857         ad.u.file = file;
1858         return inode_has_perm(cred, file_inode(file), av, &ad);
1859 }
1860
1861 #ifdef CONFIG_BPF_SYSCALL
1862 static int bpf_fd_pass(struct file *file, u32 sid);
1863 #endif
1864
1865 /* Check whether a task can use an open file descriptor to
1866    access an inode in a given way.  Check access to the
1867    descriptor itself, and then use dentry_has_perm to
1868    check a particular permission to the file.
1869    Access to the descriptor is implicitly granted if it
1870    has the same SID as the process.  If av is zero, then
1871    access to the file is not checked, e.g. for cases
1872    where only the descriptor is affected like seek. */
1873 static int file_has_perm(const struct cred *cred,
1874                          struct file *file,
1875                          u32 av)
1876 {
1877         struct file_security_struct *fsec = file->f_security;
1878         struct inode *inode = file_inode(file);
1879         struct common_audit_data ad;
1880         u32 sid = cred_sid(cred);
1881         int rc;
1882
1883         ad.type = LSM_AUDIT_DATA_FILE;
1884         ad.u.file = file;
1885
1886         if (sid != fsec->sid) {
1887                 rc = avc_has_perm(&selinux_state,
1888                                   sid, fsec->sid,
1889                                   SECCLASS_FD,
1890                                   FD__USE,
1891                                   &ad);
1892                 if (rc)
1893                         goto out;
1894         }
1895
1896 #ifdef CONFIG_BPF_SYSCALL
1897         rc = bpf_fd_pass(file, cred_sid(cred));
1898         if (rc)
1899                 return rc;
1900 #endif
1901
1902         /* av is zero if only checking access to the descriptor. */
1903         rc = 0;
1904         if (av)
1905                 rc = inode_has_perm(cred, inode, av, &ad);
1906
1907 out:
1908         return rc;
1909 }
1910
1911 /*
1912  * Determine the label for an inode that might be unioned.
1913  */
1914 static int
1915 selinux_determine_inode_label(const struct task_security_struct *tsec,
1916                                  struct inode *dir,
1917                                  const struct qstr *name, u16 tclass,
1918                                  u32 *_new_isid)
1919 {
1920         const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1921
1922         if ((sbsec->flags & SE_SBINITIALIZED) &&
1923             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1924                 *_new_isid = sbsec->mntpoint_sid;
1925         } else if ((sbsec->flags & SBLABEL_MNT) &&
1926                    tsec->create_sid) {
1927                 *_new_isid = tsec->create_sid;
1928         } else {
1929                 const struct inode_security_struct *dsec = inode_security(dir);
1930                 return security_transition_sid(&selinux_state, tsec->sid,
1931                                                dsec->sid, tclass,
1932                                                name, _new_isid);
1933         }
1934
1935         return 0;
1936 }
1937
1938 /* Check whether a task can create a file. */
1939 static int may_create(struct inode *dir,
1940                       struct dentry *dentry,
1941                       u16 tclass)
1942 {
1943         const struct task_security_struct *tsec = current_security();
1944         struct inode_security_struct *dsec;
1945         struct superblock_security_struct *sbsec;
1946         u32 sid, newsid;
1947         struct common_audit_data ad;
1948         int rc;
1949
1950         dsec = inode_security(dir);
1951         sbsec = dir->i_sb->s_security;
1952
1953         sid = tsec->sid;
1954
1955         ad.type = LSM_AUDIT_DATA_DENTRY;
1956         ad.u.dentry = dentry;
1957
1958         rc = avc_has_perm(&selinux_state,
1959                           sid, dsec->sid, SECCLASS_DIR,
1960                           DIR__ADD_NAME | DIR__SEARCH,
1961                           &ad);
1962         if (rc)
1963                 return rc;
1964
1965         rc = selinux_determine_inode_label(current_security(), dir,
1966                                            &dentry->d_name, tclass, &newsid);
1967         if (rc)
1968                 return rc;
1969
1970         rc = avc_has_perm(&selinux_state,
1971                           sid, newsid, tclass, FILE__CREATE, &ad);
1972         if (rc)
1973                 return rc;
1974
1975         return avc_has_perm(&selinux_state,
1976                             newsid, sbsec->sid,
1977                             SECCLASS_FILESYSTEM,
1978                             FILESYSTEM__ASSOCIATE, &ad);
1979 }
1980
1981 #define MAY_LINK        0
1982 #define MAY_UNLINK      1
1983 #define MAY_RMDIR       2
1984
1985 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1986 static int may_link(struct inode *dir,
1987                     struct dentry *dentry,
1988                     int kind)
1989
1990 {
1991         struct inode_security_struct *dsec, *isec;
1992         struct common_audit_data ad;
1993         u32 sid = current_sid();
1994         u32 av;
1995         int rc;
1996
1997         dsec = inode_security(dir);
1998         isec = backing_inode_security(dentry);
1999
2000         ad.type = LSM_AUDIT_DATA_DENTRY;
2001         ad.u.dentry = dentry;
2002
2003         av = DIR__SEARCH;
2004         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
2005         rc = avc_has_perm(&selinux_state,
2006                           sid, dsec->sid, SECCLASS_DIR, av, &ad);
2007         if (rc)
2008                 return rc;
2009
2010         switch (kind) {
2011         case MAY_LINK:
2012                 av = FILE__LINK;
2013                 break;
2014         case MAY_UNLINK:
2015                 av = FILE__UNLINK;
2016                 break;
2017         case MAY_RMDIR:
2018                 av = DIR__RMDIR;
2019                 break;
2020         default:
2021                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
2022                         __func__, kind);
2023                 return 0;
2024         }
2025
2026         rc = avc_has_perm(&selinux_state,
2027                           sid, isec->sid, isec->sclass, av, &ad);
2028         return rc;
2029 }
2030
2031 static inline int may_rename(struct inode *old_dir,
2032                              struct dentry *old_dentry,
2033                              struct inode *new_dir,
2034                              struct dentry *new_dentry)
2035 {
2036         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
2037         struct common_audit_data ad;
2038         u32 sid = current_sid();
2039         u32 av;
2040         int old_is_dir, new_is_dir;
2041         int rc;
2042
2043         old_dsec = inode_security(old_dir);
2044         old_isec = backing_inode_security(old_dentry);
2045         old_is_dir = d_is_dir(old_dentry);
2046         new_dsec = inode_security(new_dir);
2047
2048         ad.type = LSM_AUDIT_DATA_DENTRY;
2049
2050         ad.u.dentry = old_dentry;
2051         rc = avc_has_perm(&selinux_state,
2052                           sid, old_dsec->sid, SECCLASS_DIR,
2053                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
2054         if (rc)
2055                 return rc;
2056         rc = avc_has_perm(&selinux_state,
2057                           sid, old_isec->sid,
2058                           old_isec->sclass, FILE__RENAME, &ad);
2059         if (rc)
2060                 return rc;
2061         if (old_is_dir && new_dir != old_dir) {
2062                 rc = avc_has_perm(&selinux_state,
2063                                   sid, old_isec->sid,
2064                                   old_isec->sclass, DIR__REPARENT, &ad);
2065                 if (rc)
2066                         return rc;
2067         }
2068
2069         ad.u.dentry = new_dentry;
2070         av = DIR__ADD_NAME | DIR__SEARCH;
2071         if (d_is_positive(new_dentry))
2072                 av |= DIR__REMOVE_NAME;
2073         rc = avc_has_perm(&selinux_state,
2074                           sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
2075         if (rc)
2076                 return rc;
2077         if (d_is_positive(new_dentry)) {
2078                 new_isec = backing_inode_security(new_dentry);
2079                 new_is_dir = d_is_dir(new_dentry);
2080                 rc = avc_has_perm(&selinux_state,
2081                                   sid, new_isec->sid,
2082                                   new_isec->sclass,
2083                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
2084                 if (rc)
2085                         return rc;
2086         }
2087
2088         return 0;
2089 }
2090
2091 /* Check whether a task can perform a filesystem operation. */
2092 static int superblock_has_perm(const struct cred *cred,
2093                                struct super_block *sb,
2094                                u32 perms,
2095                                struct common_audit_data *ad)
2096 {
2097         struct superblock_security_struct *sbsec;
2098         u32 sid = cred_sid(cred);
2099
2100         sbsec = sb->s_security;
2101         return avc_has_perm(&selinux_state,
2102                             sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
2103 }
2104
2105 /* Convert a Linux mode and permission mask to an access vector. */
2106 static inline u32 file_mask_to_av(int mode, int mask)
2107 {
2108         u32 av = 0;
2109
2110         if (!S_ISDIR(mode)) {
2111                 if (mask & MAY_EXEC)
2112                         av |= FILE__EXECUTE;
2113                 if (mask & MAY_READ)
2114                         av |= FILE__READ;
2115
2116                 if (mask & MAY_APPEND)
2117                         av |= FILE__APPEND;
2118                 else if (mask & MAY_WRITE)
2119                         av |= FILE__WRITE;
2120
2121         } else {
2122                 if (mask & MAY_EXEC)
2123                         av |= DIR__SEARCH;
2124                 if (mask & MAY_WRITE)
2125                         av |= DIR__WRITE;
2126                 if (mask & MAY_READ)
2127                         av |= DIR__READ;
2128         }
2129
2130         return av;
2131 }
2132
2133 /* Convert a Linux file to an access vector. */
2134 static inline u32 file_to_av(struct file *file)
2135 {
2136         u32 av = 0;
2137
2138         if (file->f_mode & FMODE_READ)
2139                 av |= FILE__READ;
2140         if (file->f_mode & FMODE_WRITE) {
2141                 if (file->f_flags & O_APPEND)
2142                         av |= FILE__APPEND;
2143                 else
2144                         av |= FILE__WRITE;
2145         }
2146         if (!av) {
2147                 /*
2148                  * Special file opened with flags 3 for ioctl-only use.
2149                  */
2150                 av = FILE__IOCTL;
2151         }
2152
2153         return av;
2154 }
2155
2156 /*
2157  * Convert a file to an access vector and include the correct open
2158  * open permission.
2159  */
2160 static inline u32 open_file_to_av(struct file *file)
2161 {
2162         u32 av = file_to_av(file);
2163         struct inode *inode = file_inode(file);
2164
2165         if (selinux_policycap_openperm() &&
2166             inode->i_sb->s_magic != SOCKFS_MAGIC)
2167                 av |= FILE__OPEN;
2168
2169         return av;
2170 }
2171
2172 /* Hook functions begin here. */
2173
2174 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2175 {
2176         u32 mysid = current_sid();
2177         u32 mgrsid = task_sid(mgr);
2178
2179         return avc_has_perm(&selinux_state,
2180                             mysid, mgrsid, SECCLASS_BINDER,
2181                             BINDER__SET_CONTEXT_MGR, NULL);
2182 }
2183
2184 static int selinux_binder_transaction(struct task_struct *from,
2185                                       struct task_struct *to)
2186 {
2187         u32 mysid = current_sid();
2188         u32 fromsid = task_sid(from);
2189         u32 tosid = task_sid(to);
2190         int rc;
2191
2192         if (mysid != fromsid) {
2193                 rc = avc_has_perm(&selinux_state,
2194                                   mysid, fromsid, SECCLASS_BINDER,
2195                                   BINDER__IMPERSONATE, NULL);
2196                 if (rc)
2197                         return rc;
2198         }
2199
2200         return avc_has_perm(&selinux_state,
2201                             fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2202                             NULL);
2203 }
2204
2205 static int selinux_binder_transfer_binder(struct task_struct *from,
2206                                           struct task_struct *to)
2207 {
2208         u32 fromsid = task_sid(from);
2209         u32 tosid = task_sid(to);
2210
2211         return avc_has_perm(&selinux_state,
2212                             fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2213                             NULL);
2214 }
2215
2216 static int selinux_binder_transfer_file(struct task_struct *from,
2217                                         struct task_struct *to,
2218                                         struct file *file)
2219 {
2220         u32 sid = task_sid(to);
2221         struct file_security_struct *fsec = file->f_security;
2222         struct dentry *dentry = file->f_path.dentry;
2223         struct inode_security_struct *isec;
2224         struct common_audit_data ad;
2225         int rc;
2226
2227         ad.type = LSM_AUDIT_DATA_PATH;
2228         ad.u.path = file->f_path;
2229
2230         if (sid != fsec->sid) {
2231                 rc = avc_has_perm(&selinux_state,
2232                                   sid, fsec->sid,
2233                                   SECCLASS_FD,
2234                                   FD__USE,
2235                                   &ad);
2236                 if (rc)
2237                         return rc;
2238         }
2239
2240 #ifdef CONFIG_BPF_SYSCALL
2241         rc = bpf_fd_pass(file, sid);
2242         if (rc)
2243                 return rc;
2244 #endif
2245
2246         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2247                 return 0;
2248
2249         isec = backing_inode_security(dentry);
2250         return avc_has_perm(&selinux_state,
2251                             sid, isec->sid, isec->sclass, file_to_av(file),
2252                             &ad);
2253 }
2254
2255 static int selinux_ptrace_access_check(struct task_struct *child,
2256                                      unsigned int mode)
2257 {
2258         u32 sid = current_sid();
2259         u32 csid = task_sid(child);
2260
2261         if (mode & PTRACE_MODE_READ)
2262                 return avc_has_perm(&selinux_state,
2263                                     sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2264
2265         return avc_has_perm(&selinux_state,
2266                             sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2267 }
2268
2269 static int selinux_ptrace_traceme(struct task_struct *parent)
2270 {
2271         return avc_has_perm(&selinux_state,
2272                             task_sid(parent), current_sid(), SECCLASS_PROCESS,
2273                             PROCESS__PTRACE, NULL);
2274 }
2275
2276 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2277                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2278 {
2279         return avc_has_perm(&selinux_state,
2280                             current_sid(), task_sid(target), SECCLASS_PROCESS,
2281                             PROCESS__GETCAP, NULL);
2282 }
2283
2284 static int selinux_capset(struct cred *new, const struct cred *old,
2285                           const kernel_cap_t *effective,
2286                           const kernel_cap_t *inheritable,
2287                           const kernel_cap_t *permitted)
2288 {
2289         return avc_has_perm(&selinux_state,
2290                             cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2291                             PROCESS__SETCAP, NULL);
2292 }
2293
2294 /*
2295  * (This comment used to live with the selinux_task_setuid hook,
2296  * which was removed).
2297  *
2298  * Since setuid only affects the current process, and since the SELinux
2299  * controls are not based on the Linux identity attributes, SELinux does not
2300  * need to control this operation.  However, SELinux does control the use of
2301  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2302  */
2303
2304 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2305                            int cap, int audit)
2306 {
2307         return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2308 }
2309
2310 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2311 {
2312         const struct cred *cred = current_cred();
2313         int rc = 0;
2314
2315         if (!sb)
2316                 return 0;
2317
2318         switch (cmds) {
2319         case Q_SYNC:
2320         case Q_QUOTAON:
2321         case Q_QUOTAOFF:
2322         case Q_SETINFO:
2323         case Q_SETQUOTA:
2324                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2325                 break;
2326         case Q_GETFMT:
2327         case Q_GETINFO:
2328         case Q_GETQUOTA:
2329                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2330                 break;
2331         default:
2332                 rc = 0;  /* let the kernel handle invalid cmds */
2333                 break;
2334         }
2335         return rc;
2336 }
2337
2338 static int selinux_quota_on(struct dentry *dentry)
2339 {
2340         const struct cred *cred = current_cred();
2341
2342         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2343 }
2344
2345 static int selinux_syslog(int type)
2346 {
2347         switch (type) {
2348         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2349         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2350                 return avc_has_perm(&selinux_state,
2351                                     current_sid(), SECINITSID_KERNEL,
2352                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2353         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2354         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2355         /* Set level of messages printed to console */
2356         case SYSLOG_ACTION_CONSOLE_LEVEL:
2357                 return avc_has_perm(&selinux_state,
2358                                     current_sid(), SECINITSID_KERNEL,
2359                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2360                                     NULL);
2361         }
2362         /* All other syslog types */
2363         return avc_has_perm(&selinux_state,
2364                             current_sid(), SECINITSID_KERNEL,
2365                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2366 }
2367
2368 /*
2369  * Check that a process has enough memory to allocate a new virtual
2370  * mapping. 0 means there is enough memory for the allocation to
2371  * succeed and -ENOMEM implies there is not.
2372  *
2373  * Do not audit the selinux permission check, as this is applied to all
2374  * processes that allocate mappings.
2375  */
2376 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2377 {
2378         int rc, cap_sys_admin = 0;
2379
2380         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2381                                  SECURITY_CAP_NOAUDIT, true);
2382         if (rc == 0)
2383                 cap_sys_admin = 1;
2384
2385         return cap_sys_admin;
2386 }
2387
2388 /* binprm security operations */
2389
2390 static u32 ptrace_parent_sid(void)
2391 {
2392         u32 sid = 0;
2393         struct task_struct *tracer;
2394
2395         rcu_read_lock();
2396         tracer = ptrace_parent(current);
2397         if (tracer)
2398                 sid = task_sid(tracer);
2399         rcu_read_unlock();
2400
2401         return sid;
2402 }
2403
2404 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2405                             const struct task_security_struct *old_tsec,
2406                             const struct task_security_struct *new_tsec)
2407 {
2408         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2409         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2410         int rc;
2411         u32 av;
2412
2413         if (!nnp && !nosuid)
2414                 return 0; /* neither NNP nor nosuid */
2415
2416         if (new_tsec->sid == old_tsec->sid)
2417                 return 0; /* No change in credentials */
2418
2419         /*
2420          * If the policy enables the nnp_nosuid_transition policy capability,
2421          * then we permit transitions under NNP or nosuid if the
2422          * policy allows the corresponding permission between
2423          * the old and new contexts.
2424          */
2425         if (selinux_policycap_nnp_nosuid_transition()) {
2426                 av = 0;
2427                 if (nnp)
2428                         av |= PROCESS2__NNP_TRANSITION;
2429                 if (nosuid)
2430                         av |= PROCESS2__NOSUID_TRANSITION;
2431                 rc = avc_has_perm(&selinux_state,
2432                                   old_tsec->sid, new_tsec->sid,
2433                                   SECCLASS_PROCESS2, av, NULL);
2434                 if (!rc)
2435                         return 0;
2436         }
2437
2438         /*
2439          * We also permit NNP or nosuid transitions to bounded SIDs,
2440          * i.e. SIDs that are guaranteed to only be allowed a subset
2441          * of the permissions of the current SID.
2442          */
2443         rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2444                                          new_tsec->sid);
2445         if (!rc)
2446                 return 0;
2447
2448         /*
2449          * On failure, preserve the errno values for NNP vs nosuid.
2450          * NNP:  Operation not permitted for caller.
2451          * nosuid:  Permission denied to file.
2452          */
2453         if (nnp)
2454                 return -EPERM;
2455         return -EACCES;
2456 }
2457
2458 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2459 {
2460         const struct task_security_struct *old_tsec;
2461         struct task_security_struct *new_tsec;
2462         struct inode_security_struct *isec;
2463         struct common_audit_data ad;
2464         struct inode *inode = file_inode(bprm->file);
2465         int rc;
2466
2467         /* SELinux context only depends on initial program or script and not
2468          * the script interpreter */
2469         if (bprm->called_set_creds)
2470                 return 0;
2471
2472         old_tsec = current_security();
2473         new_tsec = bprm->cred->security;
2474         isec = inode_security(inode);
2475
2476         /* Default to the current task SID. */
2477         new_tsec->sid = old_tsec->sid;
2478         new_tsec->osid = old_tsec->sid;
2479
2480         /* Reset fs, key, and sock SIDs on execve. */
2481         new_tsec->create_sid = 0;
2482         new_tsec->keycreate_sid = 0;
2483         new_tsec->sockcreate_sid = 0;
2484
2485         if (old_tsec->exec_sid) {
2486                 new_tsec->sid = old_tsec->exec_sid;
2487                 /* Reset exec SID on execve. */
2488                 new_tsec->exec_sid = 0;
2489
2490                 /* Fail on NNP or nosuid if not an allowed transition. */
2491                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2492                 if (rc)
2493                         return rc;
2494         } else {
2495                 /* Check for a default transition on this program. */
2496                 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2497                                              isec->sid, SECCLASS_PROCESS, NULL,
2498                                              &new_tsec->sid);
2499                 if (rc)
2500                         return rc;
2501
2502                 /*
2503                  * Fallback to old SID on NNP or nosuid if not an allowed
2504                  * transition.
2505                  */
2506                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2507                 if (rc)
2508                         new_tsec->sid = old_tsec->sid;
2509         }
2510
2511         ad.type = LSM_AUDIT_DATA_FILE;
2512         ad.u.file = bprm->file;
2513
2514         if (new_tsec->sid == old_tsec->sid) {
2515                 rc = avc_has_perm(&selinux_state,
2516                                   old_tsec->sid, isec->sid,
2517                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2518                 if (rc)
2519                         return rc;
2520         } else {
2521                 /* Check permissions for the transition. */
2522                 rc = avc_has_perm(&selinux_state,
2523                                   old_tsec->sid, new_tsec->sid,
2524                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2525                 if (rc)
2526                         return rc;
2527
2528                 rc = avc_has_perm(&selinux_state,
2529                                   new_tsec->sid, isec->sid,
2530                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2531                 if (rc)
2532                         return rc;
2533
2534                 /* Check for shared state */
2535                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2536                         rc = avc_has_perm(&selinux_state,
2537                                           old_tsec->sid, new_tsec->sid,
2538                                           SECCLASS_PROCESS, PROCESS__SHARE,
2539                                           NULL);
2540                         if (rc)
2541                                 return -EPERM;
2542                 }
2543
2544                 /* Make sure that anyone attempting to ptrace over a task that
2545                  * changes its SID has the appropriate permit */
2546                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2547                         u32 ptsid = ptrace_parent_sid();
2548                         if (ptsid != 0) {
2549                                 rc = avc_has_perm(&selinux_state,
2550                                                   ptsid, new_tsec->sid,
2551                                                   SECCLASS_PROCESS,
2552                                                   PROCESS__PTRACE, NULL);
2553                                 if (rc)
2554                                         return -EPERM;
2555                         }
2556                 }
2557
2558                 /* Clear any possibly unsafe personality bits on exec: */
2559                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2560
2561                 /* Enable secure mode for SIDs transitions unless
2562                    the noatsecure permission is granted between
2563                    the two SIDs, i.e. ahp returns 0. */
2564                 rc = avc_has_perm(&selinux_state,
2565                                   old_tsec->sid, new_tsec->sid,
2566                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2567                                   NULL);
2568                 bprm->secureexec |= !!rc;
2569         }
2570
2571         return 0;
2572 }
2573
2574 static int match_file(const void *p, struct file *file, unsigned fd)
2575 {
2576         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2577 }
2578
2579 /* Derived from fs/exec.c:flush_old_files. */
2580 static inline void flush_unauthorized_files(const struct cred *cred,
2581                                             struct files_struct *files)
2582 {
2583         struct file *file, *devnull = NULL;
2584         struct tty_struct *tty;
2585         int drop_tty = 0;
2586         unsigned n;
2587
2588         tty = get_current_tty();
2589         if (tty) {
2590                 spin_lock(&tty->files_lock);
2591                 if (!list_empty(&tty->tty_files)) {
2592                         struct tty_file_private *file_priv;
2593
2594                         /* Revalidate access to controlling tty.
2595                            Use file_path_has_perm on the tty path directly
2596                            rather than using file_has_perm, as this particular
2597                            open file may belong to another process and we are
2598                            only interested in the inode-based check here. */
2599                         file_priv = list_first_entry(&tty->tty_files,
2600                                                 struct tty_file_private, list);
2601                         file = file_priv->file;
2602                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2603                                 drop_tty = 1;
2604                 }
2605                 spin_unlock(&tty->files_lock);
2606                 tty_kref_put(tty);
2607         }
2608         /* Reset controlling tty. */
2609         if (drop_tty)
2610                 no_tty();
2611
2612         /* Revalidate access to inherited open files. */
2613         n = iterate_fd(files, 0, match_file, cred);
2614         if (!n) /* none found? */
2615                 return;
2616
2617         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2618         if (IS_ERR(devnull))
2619                 devnull = NULL;
2620         /* replace all the matching ones with this */
2621         do {
2622                 replace_fd(n - 1, devnull, 0);
2623         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2624         if (devnull)
2625                 fput(devnull);
2626 }
2627
2628 /*
2629  * Prepare a process for imminent new credential changes due to exec
2630  */
2631 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2632 {
2633         struct task_security_struct *new_tsec;
2634         struct rlimit *rlim, *initrlim;
2635         int rc, i;
2636
2637         new_tsec = bprm->cred->security;
2638         if (new_tsec->sid == new_tsec->osid)
2639                 return;
2640
2641         /* Close files for which the new task SID is not authorized. */
2642         flush_unauthorized_files(bprm->cred, current->files);
2643
2644         /* Always clear parent death signal on SID transitions. */
2645         current->pdeath_signal = 0;
2646
2647         /* Check whether the new SID can inherit resource limits from the old
2648          * SID.  If not, reset all soft limits to the lower of the current
2649          * task's hard limit and the init task's soft limit.
2650          *
2651          * Note that the setting of hard limits (even to lower them) can be
2652          * controlled by the setrlimit check.  The inclusion of the init task's
2653          * soft limit into the computation is to avoid resetting soft limits
2654          * higher than the default soft limit for cases where the default is
2655          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2656          */
2657         rc = avc_has_perm(&selinux_state,
2658                           new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2659                           PROCESS__RLIMITINH, NULL);
2660         if (rc) {
2661                 /* protect against do_prlimit() */
2662                 task_lock(current);
2663                 for (i = 0; i < RLIM_NLIMITS; i++) {
2664                         rlim = current->signal->rlim + i;
2665                         initrlim = init_task.signal->rlim + i;
2666                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2667                 }
2668                 task_unlock(current);
2669                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2670                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2671         }
2672 }
2673
2674 /*
2675  * Clean up the process immediately after the installation of new credentials
2676  * due to exec
2677  */
2678 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2679 {
2680         const struct task_security_struct *tsec = current_security();
2681         struct itimerval itimer;
2682         u32 osid, sid;
2683         int rc, i;
2684
2685         osid = tsec->osid;
2686         sid = tsec->sid;
2687
2688         if (sid == osid)
2689                 return;
2690
2691         /* Check whether the new SID can inherit signal state from the old SID.
2692          * If not, clear itimers to avoid subsequent signal generation and
2693          * flush and unblock signals.
2694          *
2695          * This must occur _after_ the task SID has been updated so that any
2696          * kill done after the flush will be checked against the new SID.
2697          */
2698         rc = avc_has_perm(&selinux_state,
2699                           osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2700         if (rc) {
2701                 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2702                         memset(&itimer, 0, sizeof itimer);
2703                         for (i = 0; i < 3; i++)
2704                                 do_setitimer(i, &itimer, NULL);
2705                 }
2706                 spin_lock_irq(&current->sighand->siglock);
2707                 if (!fatal_signal_pending(current)) {
2708                         flush_sigqueue(&current->pending);
2709                         flush_sigqueue(&current->signal->shared_pending);
2710                         flush_signal_handlers(current, 1);
2711                         sigemptyset(&current->blocked);
2712                         recalc_sigpending();
2713                 }
2714                 spin_unlock_irq(&current->sighand->siglock);
2715         }
2716
2717         /* Wake up the parent if it is waiting so that it can recheck
2718          * wait permission to the new task SID. */
2719         read_lock(&tasklist_lock);
2720         __wake_up_parent(current, current->real_parent);
2721         read_unlock(&tasklist_lock);
2722 }
2723
2724 /* superblock security operations */
2725
2726 static int selinux_sb_alloc_security(struct super_block *sb)
2727 {
2728         return superblock_alloc_security(sb);
2729 }
2730
2731 static void selinux_sb_free_security(struct super_block *sb)
2732 {
2733         superblock_free_security(sb);
2734 }
2735
2736 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2737 {
2738         if (plen > olen)
2739                 return 0;
2740
2741         return !memcmp(prefix, option, plen);
2742 }
2743
2744 static inline int selinux_option(char *option, int len)
2745 {
2746         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2747                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2748                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2749                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2750                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2751 }
2752
2753 static inline void take_option(char **to, char *from, int *first, int len)
2754 {
2755         if (!*first) {
2756                 **to = ',';
2757                 *to += 1;
2758         } else
2759                 *first = 0;
2760         memcpy(*to, from, len);
2761         *to += len;
2762 }
2763
2764 static inline void take_selinux_option(char **to, char *from, int *first,
2765                                        int len)
2766 {
2767         int current_size = 0;
2768
2769         if (!*first) {
2770                 **to = '|';
2771                 *to += 1;
2772         } else
2773                 *first = 0;
2774
2775         while (current_size < len) {
2776                 if (*from != '"') {
2777                         **to = *from;
2778                         *to += 1;
2779                 }
2780                 from += 1;
2781                 current_size += 1;
2782         }
2783 }
2784
2785 static int selinux_sb_copy_data(char *orig, char *copy)
2786 {
2787         int fnosec, fsec, rc = 0;
2788         char *in_save, *in_curr, *in_end;
2789         char *sec_curr, *nosec_save, *nosec;
2790         int open_quote = 0;
2791
2792         in_curr = orig;
2793         sec_curr = copy;
2794
2795         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2796         if (!nosec) {
2797                 rc = -ENOMEM;
2798                 goto out;
2799         }
2800
2801         nosec_save = nosec;
2802         fnosec = fsec = 1;
2803         in_save = in_end = orig;
2804
2805         do {
2806                 if (*in_end == '"')
2807                         open_quote = !open_quote;
2808                 if ((*in_end == ',' && open_quote == 0) ||
2809                                 *in_end == '\0') {
2810                         int len = in_end - in_curr;
2811
2812                         if (selinux_option(in_curr, len))
2813                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2814                         else
2815                                 take_option(&nosec, in_curr, &fnosec, len);
2816
2817                         in_curr = in_end + 1;
2818                 }
2819         } while (*in_end++);
2820
2821         strcpy(in_save, nosec_save);
2822         free_page((unsigned long)nosec_save);
2823 out:
2824         return rc;
2825 }
2826
2827 static int selinux_sb_remount(struct super_block *sb, void *data)
2828 {
2829         int rc, i, *flags;
2830         struct security_mnt_opts opts;
2831         char *secdata, **mount_options;
2832         struct superblock_security_struct *sbsec = sb->s_security;
2833
2834         if (!(sbsec->flags & SE_SBINITIALIZED))
2835                 return 0;
2836
2837         if (!data)
2838                 return 0;
2839
2840         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2841                 return 0;
2842
2843         security_init_mnt_opts(&opts);
2844         secdata = alloc_secdata();
2845         if (!secdata)
2846                 return -ENOMEM;
2847         rc = selinux_sb_copy_data(data, secdata);
2848         if (rc)
2849                 goto out_free_secdata;
2850
2851         rc = selinux_parse_opts_str(secdata, &opts);
2852         if (rc)
2853                 goto out_free_secdata;
2854
2855         mount_options = opts.mnt_opts;
2856         flags = opts.mnt_opts_flags;
2857
2858         for (i = 0; i < opts.num_mnt_opts; i++) {
2859                 u32 sid;
2860
2861                 if (flags[i] == SBLABEL_MNT)
2862                         continue;
2863                 rc = security_context_str_to_sid(&selinux_state,
2864                                                  mount_options[i], &sid,
2865                                                  GFP_KERNEL);
2866                 if (rc) {
2867                         printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2868                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2869                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2870                         goto out_free_opts;
2871                 }
2872                 rc = -EINVAL;
2873                 switch (flags[i]) {
2874                 case FSCONTEXT_MNT:
2875                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2876                                 goto out_bad_option;
2877                         break;
2878                 case CONTEXT_MNT:
2879                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2880                                 goto out_bad_option;
2881                         break;
2882                 case ROOTCONTEXT_MNT: {
2883                         struct inode_security_struct *root_isec;
2884                         root_isec = backing_inode_security(sb->s_root);
2885
2886                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2887                                 goto out_bad_option;
2888                         break;
2889                 }
2890                 case DEFCONTEXT_MNT:
2891                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2892                                 goto out_bad_option;
2893                         break;
2894                 default:
2895                         goto out_free_opts;
2896                 }
2897         }
2898
2899         rc = 0;
2900 out_free_opts:
2901         security_free_mnt_opts(&opts);
2902 out_free_secdata:
2903         free_secdata(secdata);
2904         return rc;
2905 out_bad_option:
2906         printk(KERN_WARNING "SELinux: unable to change security options "
2907                "during remount (dev %s, type=%s)\n", sb->s_id,
2908                sb->s_type->name);
2909         goto out_free_opts;
2910 }
2911
2912 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2913 {
2914         const struct cred *cred = current_cred();
2915         struct common_audit_data ad;
2916         int rc;
2917
2918         rc = superblock_doinit(sb, data);
2919         if (rc)
2920                 return rc;
2921
2922         /* Allow all mounts performed by the kernel */
2923         if (flags & MS_KERNMOUNT)
2924                 return 0;
2925
2926         ad.type = LSM_AUDIT_DATA_DENTRY;
2927         ad.u.dentry = sb->s_root;
2928         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2929 }
2930
2931 static int selinux_sb_statfs(struct dentry *dentry)
2932 {
2933         const struct cred *cred = current_cred();
2934         struct common_audit_data ad;
2935
2936         ad.type = LSM_AUDIT_DATA_DENTRY;
2937         ad.u.dentry = dentry->d_sb->s_root;
2938         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2939 }
2940
2941 static int selinux_mount(const char *dev_name,
2942                          const struct path *path,
2943                          const char *type,
2944                          unsigned long flags,
2945                          void *data)
2946 {
2947         const struct cred *cred = current_cred();
2948
2949         if (flags & MS_REMOUNT)
2950                 return superblock_has_perm(cred, path->dentry->d_sb,
2951                                            FILESYSTEM__REMOUNT, NULL);
2952         else
2953                 return path_has_perm(cred, path, FILE__MOUNTON);
2954 }
2955
2956 static int selinux_umount(struct vfsmount *mnt, int flags)
2957 {
2958         const struct cred *cred = current_cred();
2959
2960         return superblock_has_perm(cred, mnt->mnt_sb,
2961                                    FILESYSTEM__UNMOUNT, NULL);
2962 }
2963
2964 /* inode security operations */
2965
2966 static int selinux_inode_alloc_security(struct inode *inode)
2967 {
2968         return inode_alloc_security(inode);
2969 }
2970
2971 static void selinux_inode_free_security(struct inode *inode)
2972 {
2973         inode_free_security(inode);
2974 }
2975
2976 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2977                                         const struct qstr *name, void **ctx,
2978                                         u32 *ctxlen)
2979 {
2980         u32 newsid;
2981         int rc;
2982
2983         rc = selinux_determine_inode_label(current_security(),
2984                                            d_inode(dentry->d_parent), name,
2985                                            inode_mode_to_security_class(mode),
2986                                            &newsid);
2987         if (rc)
2988                 return rc;
2989
2990         return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2991                                        ctxlen);
2992 }
2993
2994 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2995                                           struct qstr *name,
2996                                           const struct cred *old,
2997                                           struct cred *new)
2998 {
2999         u32 newsid;
3000         int rc;
3001         struct task_security_struct *tsec;
3002
3003         rc = selinux_determine_inode_label(old->security,
3004                                            d_inode(dentry->d_parent), name,
3005                                            inode_mode_to_security_class(mode),
3006                                            &newsid);
3007         if (rc)
3008                 return rc;
3009
3010         tsec = new->security;
3011         tsec->create_sid = newsid;
3012         return 0;
3013 }
3014
3015 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
3016                                        const struct qstr *qstr,
3017                                        const char **name,
3018                                        void **value, size_t *len)
3019 {
3020         const struct task_security_struct *tsec = current_security();
3021         struct superblock_security_struct *sbsec;
3022         u32 newsid, clen;
3023         int rc;
3024         char *context;
3025
3026         sbsec = dir->i_sb->s_security;
3027
3028         newsid = tsec->create_sid;
3029
3030         rc = selinux_determine_inode_label(current_security(),
3031                 dir, qstr,
3032                 inode_mode_to_security_class(inode->i_mode),
3033                 &newsid);
3034         if (rc)
3035                 return rc;
3036
3037         /* Possibly defer initialization to selinux_complete_init. */
3038         if (sbsec->flags & SE_SBINITIALIZED) {
3039                 struct inode_security_struct *isec = inode->i_security;
3040                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3041                 isec->sid = newsid;
3042                 isec->initialized = LABEL_INITIALIZED;
3043         }
3044
3045         if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT))
3046                 return -EOPNOTSUPP;
3047
3048         if (name)
3049                 *name = XATTR_SELINUX_SUFFIX;
3050
3051         if (value && len) {
3052                 rc = security_sid_to_context_force(&selinux_state, newsid,
3053                                                    &context, &clen);
3054                 if (rc)
3055                         return rc;
3056                 *value = context;
3057                 *len = clen;
3058         }
3059
3060         return 0;
3061 }
3062
3063 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3064 {
3065         return may_create(dir, dentry, SECCLASS_FILE);
3066 }
3067
3068 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3069 {
3070         return may_link(dir, old_dentry, MAY_LINK);
3071 }
3072
3073 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3074 {
3075         return may_link(dir, dentry, MAY_UNLINK);
3076 }
3077
3078 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3079 {
3080         return may_create(dir, dentry, SECCLASS_LNK_FILE);
3081 }
3082
3083 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3084 {
3085         return may_create(dir, dentry, SECCLASS_DIR);
3086 }
3087
3088 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3089 {
3090         return may_link(dir, dentry, MAY_RMDIR);
3091 }
3092
3093 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3094 {
3095         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3096 }
3097
3098 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3099                                 struct inode *new_inode, struct dentry *new_dentry)
3100 {
3101         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3102 }
3103
3104 static int selinux_inode_readlink(struct dentry *dentry)
3105 {
3106         const struct cred *cred = current_cred();
3107
3108         return dentry_has_perm(cred, dentry, FILE__READ);
3109 }
3110
3111 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3112                                      bool rcu)
3113 {
3114         const struct cred *cred = current_cred();
3115         struct common_audit_data ad;
3116         struct inode_security_struct *isec;
3117         u32 sid;
3118
3119         validate_creds(cred);
3120
3121         ad.type = LSM_AUDIT_DATA_DENTRY;
3122         ad.u.dentry = dentry;
3123         sid = cred_sid(cred);
3124         isec = inode_security_rcu(inode, rcu);
3125         if (IS_ERR(isec))
3126                 return PTR_ERR(isec);
3127
3128         return avc_has_perm_flags(&selinux_state,
3129                                   sid, isec->sid, isec->sclass, FILE__READ, &ad,
3130                                   rcu ? MAY_NOT_BLOCK : 0);
3131 }
3132
3133 static noinline int audit_inode_permission(struct inode *inode,
3134                                            u32 perms, u32 audited, u32 denied,
3135                                            int result,
3136                                            unsigned flags)
3137 {
3138         struct common_audit_data ad;
3139         struct inode_security_struct *isec = inode->i_security;
3140         int rc;
3141
3142         ad.type = LSM_AUDIT_DATA_INODE;
3143         ad.u.inode = inode;
3144
3145         rc = slow_avc_audit(&selinux_state,
3146                             current_sid(), isec->sid, isec->sclass, perms,
3147                             audited, denied, result, &ad, flags);
3148         if (rc)
3149                 return rc;
3150         return 0;
3151 }
3152
3153 static int selinux_inode_permission(struct inode *inode, int mask)
3154 {
3155         const struct cred *cred = current_cred();
3156         u32 perms;
3157         bool from_access;
3158         unsigned flags = mask & MAY_NOT_BLOCK;
3159         struct inode_security_struct *isec;
3160         u32 sid;
3161         struct av_decision avd;
3162         int rc, rc2;
3163         u32 audited, denied;
3164
3165         from_access = mask & MAY_ACCESS;
3166         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3167
3168         /* No permission to check.  Existence test. */
3169         if (!mask)
3170                 return 0;
3171
3172         validate_creds(cred);
3173
3174         if (unlikely(IS_PRIVATE(inode)))
3175                 return 0;
3176
3177         perms = file_mask_to_av(inode->i_mode, mask);
3178
3179         sid = cred_sid(cred);
3180         isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3181         if (IS_ERR(isec))
3182                 return PTR_ERR(isec);
3183
3184         rc = avc_has_perm_noaudit(&selinux_state,
3185                                   sid, isec->sid, isec->sclass, perms, 0, &avd);
3186         audited = avc_audit_required(perms, &avd, rc,
3187                                      from_access ? FILE__AUDIT_ACCESS : 0,
3188                                      &denied);
3189         if (likely(!audited))
3190                 return rc;
3191
3192         rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3193         if (rc2)
3194                 return rc2;
3195         return rc;
3196 }
3197
3198 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3199 {
3200         const struct cred *cred = current_cred();
3201         struct inode *inode = d_backing_inode(dentry);
3202         unsigned int ia_valid = iattr->ia_valid;
3203         __u32 av = FILE__WRITE;
3204
3205         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3206         if (ia_valid & ATTR_FORCE) {
3207                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3208                               ATTR_FORCE);
3209                 if (!ia_valid)
3210                         return 0;
3211         }
3212
3213         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3214                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3215                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3216
3217         if (selinux_policycap_openperm() &&
3218             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3219             (ia_valid & ATTR_SIZE) &&
3220             !(ia_valid & ATTR_FILE))
3221                 av |= FILE__OPEN;
3222
3223         return dentry_has_perm(cred, dentry, av);
3224 }
3225
3226 static int selinux_inode_getattr(const struct path *path)
3227 {
3228         return path_has_perm(current_cred(), path, FILE__GETATTR);
3229 }
3230
3231 static bool has_cap_mac_admin(bool audit)
3232 {
3233         const struct cred *cred = current_cred();
3234         int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT;
3235
3236         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit))
3237                 return false;
3238         if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true))
3239                 return false;
3240         return true;
3241 }
3242
3243 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3244                                   const void *value, size_t size, int flags)
3245 {
3246         struct inode *inode = d_backing_inode(dentry);
3247         struct inode_security_struct *isec;
3248         struct superblock_security_struct *sbsec;
3249         struct common_audit_data ad;
3250         u32 newsid, sid = current_sid();
3251         int rc = 0;
3252
3253         if (strcmp(name, XATTR_NAME_SELINUX)) {
3254                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3255                 if (rc)
3256                         return rc;
3257
3258                 /* Not an attribute we recognize, so just check the
3259                    ordinary setattr permission. */
3260                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3261         }
3262
3263         sbsec = inode->i_sb->s_security;
3264         if (!(sbsec->flags & SBLABEL_MNT))
3265                 return -EOPNOTSUPP;
3266
3267         if (!inode_owner_or_capable(inode))
3268                 return -EPERM;
3269
3270         ad.type = LSM_AUDIT_DATA_DENTRY;
3271         ad.u.dentry = dentry;
3272
3273         isec = backing_inode_security(dentry);
3274         rc = avc_has_perm(&selinux_state,
3275                           sid, isec->sid, isec->sclass,
3276                           FILE__RELABELFROM, &ad);
3277         if (rc)
3278                 return rc;
3279
3280         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3281                                      GFP_KERNEL);
3282         if (rc == -EINVAL) {
3283                 if (!has_cap_mac_admin(true)) {
3284                         struct audit_buffer *ab;
3285                         size_t audit_size;
3286
3287                         /* We strip a nul only if it is at the end, otherwise the
3288                          * context contains a nul and we should audit that */
3289                         if (value) {
3290                                 const char *str = value;
3291
3292                                 if (str[size - 1] == '\0')
3293                                         audit_size = size - 1;
3294                                 else
3295                                         audit_size = size;
3296                         } else {
3297                                 audit_size = 0;
3298                         }
3299                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3300                         audit_log_format(ab, "op=setxattr invalid_context=");
3301                         audit_log_n_untrustedstring(ab, value, audit_size);
3302                         audit_log_end(ab);
3303
3304                         return rc;
3305                 }
3306                 rc = security_context_to_sid_force(&selinux_state, value,
3307                                                    size, &newsid);
3308         }
3309         if (rc)
3310                 return rc;
3311
3312         rc = avc_has_perm(&selinux_state,
3313                           sid, newsid, isec->sclass,
3314                           FILE__RELABELTO, &ad);
3315         if (rc)
3316                 return rc;
3317
3318         rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3319                                           sid, isec->sclass);
3320         if (rc)
3321                 return rc;
3322
3323         return avc_has_perm(&selinux_state,
3324                             newsid,
3325                             sbsec->sid,
3326                             SECCLASS_FILESYSTEM,
3327                             FILESYSTEM__ASSOCIATE,
3328                             &ad);
3329 }
3330
3331 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3332                                         const void *value, size_t size,
3333                                         int flags)
3334 {
3335         struct inode *inode = d_backing_inode(dentry);
3336         struct inode_security_struct *isec;
3337         u32 newsid;
3338         int rc;
3339
3340         if (strcmp(name, XATTR_NAME_SELINUX)) {
3341                 /* Not an attribute we recognize, so nothing to do. */
3342                 return;
3343         }
3344
3345         rc = security_context_to_sid_force(&selinux_state, value, size,
3346                                            &newsid);
3347         if (rc) {
3348                 printk(KERN_ERR "SELinux:  unable to map context to SID"
3349                        "for (%s, %lu), rc=%d\n",
3350                        inode->i_sb->s_id, inode->i_ino, -rc);
3351                 return;
3352         }
3353
3354         isec = backing_inode_security(dentry);
3355         spin_lock(&isec->lock);
3356         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3357         isec->sid = newsid;
3358         isec->initialized = LABEL_INITIALIZED;
3359         spin_unlock(&isec->lock);
3360
3361         return;
3362 }
3363
3364 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3365 {
3366         const struct cred *cred = current_cred();
3367
3368         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3369 }
3370
3371 static int selinux_inode_listxattr(struct dentry *dentry)
3372 {
3373         const struct cred *cred = current_cred();
3374
3375         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3376 }
3377
3378 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3379 {
3380         if (strcmp(name, XATTR_NAME_SELINUX)) {
3381                 int rc = cap_inode_removexattr(dentry, name);
3382                 if (rc)
3383                         return rc;
3384
3385                 /* Not an attribute we recognize, so just check the
3386                    ordinary setattr permission. */
3387                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3388         }
3389
3390         /* No one is allowed to remove a SELinux security label.
3391            You can change the label, but all data must be labeled. */
3392         return -EACCES;
3393 }
3394
3395 /*
3396  * Copy the inode security context value to the user.
3397  *
3398  * Permission check is handled by selinux_inode_getxattr hook.
3399  */
3400 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3401 {
3402         u32 size;
3403         int error;
3404         char *context = NULL;
3405         struct inode_security_struct *isec;
3406
3407         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3408                 return -EOPNOTSUPP;
3409
3410         /*
3411          * If the caller has CAP_MAC_ADMIN, then get the raw context
3412          * value even if it is not defined by current policy; otherwise,
3413          * use the in-core value under current policy.
3414          * Use the non-auditing forms of the permission checks since
3415          * getxattr may be called by unprivileged processes commonly
3416          * and lack of permission just means that we fall back to the
3417          * in-core context value, not a denial.
3418          */
3419         isec = inode_security(inode);
3420         if (has_cap_mac_admin(false))
3421                 error = security_sid_to_context_force(&selinux_state,
3422                                                       isec->sid, &context,
3423                                                       &size);
3424         else
3425                 error = security_sid_to_context(&selinux_state, isec->sid,
3426                                                 &context, &size);
3427         if (error)
3428                 return error;
3429         error = size;
3430         if (alloc) {
3431                 *buffer = context;
3432                 goto out_nofree;
3433         }
3434         kfree(context);
3435 out_nofree:
3436         return error;
3437 }
3438
3439 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3440                                      const void *value, size_t size, int flags)
3441 {
3442         struct inode_security_struct *isec = inode_security_novalidate(inode);
3443         u32 newsid;
3444         int rc;
3445
3446         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3447                 return -EOPNOTSUPP;
3448
3449         if (!value || !size)
3450                 return -EACCES;
3451
3452         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3453                                      GFP_KERNEL);
3454         if (rc)
3455                 return rc;
3456
3457         spin_lock(&isec->lock);
3458         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3459         isec->sid = newsid;
3460         isec->initialized = LABEL_INITIALIZED;
3461         spin_unlock(&isec->lock);
3462         return 0;
3463 }
3464
3465 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3466 {
3467         const int len = sizeof(XATTR_NAME_SELINUX);
3468         if (buffer && len <= buffer_size)
3469                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3470         return len;
3471 }
3472
3473 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3474 {
3475         struct inode_security_struct *isec = inode_security_novalidate(inode);
3476         *secid = isec->sid;
3477 }
3478
3479 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3480 {
3481         u32 sid;
3482         struct task_security_struct *tsec;
3483         struct cred *new_creds = *new;
3484
3485         if (new_creds == NULL) {
3486                 new_creds = prepare_creds();
3487                 if (!new_creds)
3488                         return -ENOMEM;
3489         }
3490
3491         tsec = new_creds->security;
3492         /* Get label from overlay inode and set it in create_sid */
3493         selinux_inode_getsecid(d_inode(src), &sid);
3494         tsec->create_sid = sid;
3495         *new = new_creds;
3496         return 0;
3497 }
3498
3499 static int selinux_inode_copy_up_xattr(const char *name)
3500 {
3501         /* The copy_up hook above sets the initial context on an inode, but we
3502          * don't then want to overwrite it by blindly copying all the lower
3503          * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3504          */
3505         if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3506                 return 1; /* Discard */
3507         /*
3508          * Any other attribute apart from SELINUX is not claimed, supported
3509          * by selinux.
3510          */
3511         return -EOPNOTSUPP;
3512 }
3513
3514 /* file security operations */
3515
3516 static int selinux_revalidate_file_permission(struct file *file, int mask)
3517 {
3518         const struct cred *cred = current_cred();
3519         struct inode *inode = file_inode(file);
3520
3521         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3522         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3523                 mask |= MAY_APPEND;
3524
3525         return file_has_perm(cred, file,
3526                              file_mask_to_av(inode->i_mode, mask));
3527 }
3528
3529 static int selinux_file_permission(struct file *file, int mask)
3530 {
3531         struct inode *inode = file_inode(file);
3532         struct file_security_struct *fsec = file->f_security;
3533         struct inode_security_struct *isec;
3534         u32 sid = current_sid();
3535
3536         if (!mask)
3537                 /* No permission to check.  Existence test. */
3538                 return 0;
3539
3540         isec = inode_security(inode);
3541         if (sid == fsec->sid && fsec->isid == isec->sid &&
3542             fsec->pseqno == avc_policy_seqno(&selinux_state))
3543                 /* No change since file_open check. */
3544                 return 0;
3545
3546         return selinux_revalidate_file_permission(file, mask);
3547 }
3548
3549 static int selinux_file_alloc_security(struct file *file)
3550 {
3551         return file_alloc_security(file);
3552 }
3553
3554 static void selinux_file_free_security(struct file *file)
3555 {
3556         file_free_security(file);
3557 }
3558
3559 /*
3560  * Check whether a task has the ioctl permission and cmd
3561  * operation to an inode.
3562  */
3563 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3564                 u32 requested, u16 cmd)
3565 {
3566         struct common_audit_data ad;
3567         struct file_security_struct *fsec = file->f_security;
3568         struct inode *inode = file_inode(file);
3569         struct inode_security_struct *isec;
3570         struct lsm_ioctlop_audit ioctl;
3571         u32 ssid = cred_sid(cred);
3572         int rc;
3573         u8 driver = cmd >> 8;
3574         u8 xperm = cmd & 0xff;
3575
3576         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3577         ad.u.op = &ioctl;
3578         ad.u.op->cmd = cmd;
3579         ad.u.op->path = file->f_path;
3580
3581         if (ssid != fsec->sid) {
3582                 rc = avc_has_perm(&selinux_state,
3583                                   ssid, fsec->sid,
3584                                 SECCLASS_FD,
3585                                 FD__USE,
3586                                 &ad);
3587                 if (rc)
3588                         goto out;
3589         }
3590
3591         if (unlikely(IS_PRIVATE(inode)))
3592                 return 0;
3593
3594         isec = inode_security(inode);
3595         rc = avc_has_extended_perms(&selinux_state,
3596                                     ssid, isec->sid, isec->sclass,
3597                                     requested, driver, xperm, &ad);
3598 out:
3599         return rc;
3600 }
3601
3602 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3603                               unsigned long arg)
3604 {
3605         const struct cred *cred = current_cred();
3606         int error = 0;
3607
3608         switch (cmd) {
3609         case FIONREAD:
3610         /* fall through */
3611         case FIBMAP:
3612         /* fall through */
3613         case FIGETBSZ:
3614         /* fall through */
3615         case FS_IOC_GETFLAGS:
3616         /* fall through */
3617         case FS_IOC_GETVERSION:
3618                 error = file_has_perm(cred, file, FILE__GETATTR);
3619                 break;
3620
3621         case FS_IOC_SETFLAGS:
3622         /* fall through */
3623         case FS_IOC_SETVERSION:
3624                 error = file_has_perm(cred, file, FILE__SETATTR);
3625                 break;
3626
3627         /* sys_ioctl() checks */
3628         case FIONBIO:
3629         /* fall through */
3630         case FIOASYNC:
3631                 error = file_has_perm(cred, file, 0);
3632                 break;
3633
3634         case KDSKBENT:
3635         case KDSKBSENT:
3636                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3637                                             SECURITY_CAP_AUDIT, true);
3638                 break;
3639
3640         /* default case assumes that the command will go
3641          * to the file's ioctl() function.
3642          */
3643         default:
3644                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3645         }
3646         return error;
3647 }
3648
3649 static int default_noexec;
3650
3651 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3652 {
3653         const struct cred *cred = current_cred();
3654         u32 sid = cred_sid(cred);
3655         int rc = 0;
3656
3657         if (default_noexec &&
3658             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3659                                    (!shared && (prot & PROT_WRITE)))) {
3660                 /*
3661                  * We are making executable an anonymous mapping or a
3662                  * private file mapping that will also be writable.
3663                  * This has an additional check.
3664                  */
3665                 rc = avc_has_perm(&selinux_state,
3666                                   sid, sid, SECCLASS_PROCESS,
3667                                   PROCESS__EXECMEM, NULL);
3668                 if (rc)
3669                         goto error;
3670         }
3671
3672         if (file) {
3673                 /* read access is always possible with a mapping */
3674                 u32 av = FILE__READ;
3675
3676                 /* write access only matters if the mapping is shared */
3677                 if (shared && (prot & PROT_WRITE))
3678                         av |= FILE__WRITE;
3679
3680                 if (prot & PROT_EXEC)
3681                         av |= FILE__EXECUTE;
3682
3683                 return file_has_perm(cred, file, av);
3684         }
3685
3686 error:
3687         return rc;
3688 }
3689
3690 static int selinux_mmap_addr(unsigned long addr)
3691 {
3692         int rc = 0;
3693
3694         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3695                 u32 sid = current_sid();
3696                 rc = avc_has_perm(&selinux_state,
3697                                   sid, sid, SECCLASS_MEMPROTECT,
3698                                   MEMPROTECT__MMAP_ZERO, NULL);
3699         }
3700
3701         return rc;
3702 }
3703
3704 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3705                              unsigned long prot, unsigned long flags)
3706 {
3707         struct common_audit_data ad;
3708         int rc;
3709
3710         if (file) {
3711                 ad.type = LSM_AUDIT_DATA_FILE;
3712                 ad.u.file = file;
3713                 rc = inode_has_perm(current_cred(), file_inode(file),
3714                                     FILE__MAP, &ad);
3715                 if (rc)
3716                         return rc;
3717         }
3718
3719         if (selinux_state.checkreqprot)
3720                 prot = reqprot;
3721
3722         return file_map_prot_check(file, prot,
3723                                    (flags & MAP_TYPE) == MAP_SHARED);
3724 }
3725
3726 static int selinux_file_mprotect(struct vm_area_struct *vma,
3727                                  unsigned long reqprot,
3728                                  unsigned long prot)
3729 {
3730         const struct cred *cred = current_cred();
3731         u32 sid = cred_sid(cred);
3732
3733         if (selinux_state.checkreqprot)
3734                 prot = reqprot;
3735
3736         if (default_noexec &&
3737             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3738                 int rc = 0;
3739                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3740                     vma->vm_end <= vma->vm_mm->brk) {
3741                         rc = avc_has_perm(&selinux_state,
3742                                           sid, sid, SECCLASS_PROCESS,
3743                                           PROCESS__EXECHEAP, NULL);
3744                 } else if (!vma->vm_file &&
3745                            ((vma->vm_start <= vma->vm_mm->start_stack &&
3746                              vma->vm_end >= vma->vm_mm->start_stack) ||
3747                             vma_is_stack_for_current(vma))) {
3748                         rc = avc_has_perm(&selinux_state,
3749                                           sid, sid, SECCLASS_PROCESS,
3750                                           PROCESS__EXECSTACK, NULL);
3751                 } else if (vma->vm_file && vma->anon_vma) {
3752                         /*
3753                          * We are making executable a file mapping that has
3754                          * had some COW done. Since pages might have been
3755                          * written, check ability to execute the possibly
3756                          * modified content.  This typically should only
3757                          * occur for text relocations.
3758                          */
3759                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3760                 }
3761                 if (rc)
3762                         return rc;
3763         }
3764
3765         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3766 }
3767
3768 static int selinux_file_lock(struct file *file, unsigned int cmd)
3769 {
3770         const struct cred *cred = current_cred();
3771
3772         return file_has_perm(cred, file, FILE__LOCK);
3773 }
3774
3775 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3776                               unsigned long arg)
3777 {
3778         const struct cred *cred = current_cred();
3779         int err = 0;
3780
3781         switch (cmd) {
3782         case F_SETFL:
3783                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3784                         err = file_has_perm(cred, file, FILE__WRITE);
3785                         break;
3786                 }
3787                 /* fall through */
3788         case F_SETOWN:
3789         case F_SETSIG:
3790         case F_GETFL:
3791         case F_GETOWN:
3792         case F_GETSIG:
3793         case F_GETOWNER_UIDS:
3794                 /* Just check FD__USE permission */
3795                 err = file_has_perm(cred, file, 0);
3796                 break;
3797         case F_GETLK:
3798         case F_SETLK:
3799         case F_SETLKW:
3800         case F_OFD_GETLK:
3801         case F_OFD_SETLK:
3802         case F_OFD_SETLKW:
3803 #if BITS_PER_LONG == 32
3804         case F_GETLK64:
3805         case F_SETLK64:
3806         case F_SETLKW64:
3807 #endif
3808                 err = file_has_perm(cred, file, FILE__LOCK);
3809                 break;
3810         }
3811
3812         return err;
3813 }
3814
3815 static void selinux_file_set_fowner(struct file *file)
3816 {
3817         struct file_security_struct *fsec;
3818
3819         fsec = file->f_security;
3820         fsec->fown_sid = current_sid();
3821 }
3822
3823 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3824                                        struct fown_struct *fown, int signum)
3825 {
3826         struct file *file;
3827         u32 sid = task_sid(tsk);
3828         u32 perm;
3829         struct file_security_struct *fsec;
3830
3831         /* struct fown_struct is never outside the context of a struct file */
3832         file = container_of(fown, struct file, f_owner);
3833
3834         fsec = file->f_security;
3835
3836         if (!signum)
3837                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3838         else
3839                 perm = signal_to_av(signum);
3840
3841         return avc_has_perm(&selinux_state,
3842                             fsec->fown_sid, sid,
3843                             SECCLASS_PROCESS, perm, NULL);
3844 }
3845
3846 static int selinux_file_receive(struct file *file)
3847 {
3848         const struct cred *cred = current_cred();
3849
3850         return file_has_perm(cred, file, file_to_av(file));
3851 }
3852
3853 static int selinux_file_open(struct file *file, const struct cred *cred)
3854 {
3855         struct file_security_struct *fsec;
3856         struct inode_security_struct *isec;
3857
3858         fsec = file->f_security;
3859         isec = inode_security(file_inode(file));
3860         /*
3861          * Save inode label and policy sequence number
3862          * at open-time so that selinux_file_permission
3863          * can determine whether revalidation is necessary.
3864          * Task label is already saved in the file security
3865          * struct as its SID.
3866          */
3867         fsec->isid = isec->sid;
3868         fsec->pseqno = avc_policy_seqno(&selinux_state);
3869         /*
3870          * Since the inode label or policy seqno may have changed
3871          * between the selinux_inode_permission check and the saving
3872          * of state above, recheck that access is still permitted.
3873          * Otherwise, access might never be revalidated against the
3874          * new inode label or new policy.
3875          * This check is not redundant - do not remove.
3876          */
3877         return file_path_has_perm(cred, file, open_file_to_av(file));
3878 }
3879
3880 /* task security operations */
3881
3882 static int selinux_task_alloc(struct task_struct *task,
3883                               unsigned long clone_flags)
3884 {
3885         u32 sid = current_sid();
3886
3887         return avc_has_perm(&selinux_state,
3888                             sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3889 }
3890
3891 /*
3892  * allocate the SELinux part of blank credentials
3893  */
3894 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3895 {
3896         struct task_security_struct *tsec;
3897
3898         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3899         if (!tsec)
3900                 return -ENOMEM;
3901
3902         cred->security = tsec;
3903         return 0;
3904 }
3905
3906 /*
3907  * detach and free the LSM part of a set of credentials
3908  */
3909 static void selinux_cred_free(struct cred *cred)
3910 {
3911         struct task_security_struct *tsec = cred->security;
3912
3913         /*
3914          * cred->security == NULL if security_cred_alloc_blank() or
3915          * security_prepare_creds() returned an error.
3916          */
3917         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3918         cred->security = (void *) 0x7UL;
3919         kfree(tsec);
3920 }
3921
3922 /*
3923  * prepare a new set of credentials for modification
3924  */
3925 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3926                                 gfp_t gfp)
3927 {
3928         const struct task_security_struct *old_tsec;
3929         struct task_security_struct *tsec;
3930
3931         old_tsec = old->security;
3932
3933         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3934         if (!tsec)
3935                 return -ENOMEM;
3936
3937         new->security = tsec;
3938         return 0;
3939 }
3940
3941 /*
3942  * transfer the SELinux data to a blank set of creds
3943  */
3944 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3945 {
3946         const struct task_security_struct *old_tsec = old->security;
3947         struct task_security_struct *tsec = new->security;
3948
3949         *tsec = *old_tsec;
3950 }
3951
3952 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3953 {
3954         *secid = cred_sid(c);
3955 }
3956
3957 /*
3958  * set the security data for a kernel service
3959  * - all the creation contexts are set to unlabelled
3960  */
3961 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3962 {
3963         struct task_security_struct *tsec = new->security;
3964         u32 sid = current_sid();
3965         int ret;
3966
3967         ret = avc_has_perm(&selinux_state,
3968                            sid, secid,
3969                            SECCLASS_KERNEL_SERVICE,
3970                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3971                            NULL);
3972         if (ret == 0) {
3973                 tsec->sid = secid;
3974                 tsec->create_sid = 0;
3975                 tsec->keycreate_sid = 0;
3976                 tsec->sockcreate_sid = 0;
3977         }
3978         return ret;
3979 }
3980
3981 /*
3982  * set the file creation context in a security record to the same as the
3983  * objective context of the specified inode
3984  */
3985 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3986 {
3987         struct inode_security_struct *isec = inode_security(inode);
3988         struct task_security_struct *tsec = new->security;
3989         u32 sid = current_sid();
3990         int ret;
3991
3992         ret = avc_has_perm(&selinux_state,
3993                            sid, isec->sid,
3994                            SECCLASS_KERNEL_SERVICE,
3995                            KERNEL_SERVICE__CREATE_FILES_AS,
3996                            NULL);
3997
3998         if (ret == 0)
3999                 tsec->create_sid = isec->sid;
4000         return ret;
4001 }
4002
4003 static int selinux_kernel_module_request(char *kmod_name)
4004 {
4005         struct common_audit_data ad;
4006
4007         ad.type = LSM_AUDIT_DATA_KMOD;
4008         ad.u.kmod_name = kmod_name;
4009
4010         return avc_has_perm(&selinux_state,
4011                             current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4012                             SYSTEM__MODULE_REQUEST, &ad);
4013 }
4014
4015 static int selinux_kernel_module_from_file(struct file *file)
4016 {
4017         struct common_audit_data ad;
4018         struct inode_security_struct *isec;
4019         struct file_security_struct *fsec;
4020         u32 sid = current_sid();
4021         int rc;
4022
4023         /* init_module */
4024         if (file == NULL)
4025                 return avc_has_perm(&selinux_state,
4026                                     sid, sid, SECCLASS_SYSTEM,
4027                                         SYSTEM__MODULE_LOAD, NULL);
4028
4029         /* finit_module */
4030
4031         ad.type = LSM_AUDIT_DATA_FILE;
4032         ad.u.file = file;
4033
4034         fsec = file->f_security;
4035         if (sid != fsec->sid) {
4036                 rc = avc_has_perm(&selinux_state,
4037                                   sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4038                 if (rc)
4039                         return rc;
4040         }
4041
4042         isec = inode_security(file_inode(file));
4043         return avc_has_perm(&selinux_state,
4044                             sid, isec->sid, SECCLASS_SYSTEM,
4045                                 SYSTEM__MODULE_LOAD, &ad);
4046 }
4047
4048 static int selinux_kernel_read_file(struct file *file,
4049                                     enum kernel_read_file_id id)
4050 {
4051         int rc = 0;
4052
4053         switch (id) {
4054         case READING_MODULE:
4055                 rc = selinux_kernel_module_from_file(file);
4056                 break;
4057         default:
4058                 break;
4059         }
4060
4061         return rc;
4062 }
4063
4064 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4065 {
4066         return avc_has_perm(&selinux_state,
4067                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4068                             PROCESS__SETPGID, NULL);
4069 }
4070
4071 static int selinux_task_getpgid(struct task_struct *p)
4072 {
4073         return avc_has_perm(&selinux_state,
4074                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4075                             PROCESS__GETPGID, NULL);
4076 }
4077
4078 static int selinux_task_getsid(struct task_struct *p)
4079 {
4080         return avc_has_perm(&selinux_state,
4081                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4082                             PROCESS__GETSESSION, NULL);
4083 }
4084
4085 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4086 {
4087         *secid = task_sid(p);
4088 }
4089
4090 static int selinux_task_setnice(struct task_struct *p, int nice)
4091 {
4092         return avc_has_perm(&selinux_state,
4093                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4094                             PROCESS__SETSCHED, NULL);
4095 }
4096
4097 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4098 {
4099         return avc_has_perm(&selinux_state,
4100                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4101                             PROCESS__SETSCHED, NULL);
4102 }
4103
4104 static int selinux_task_getioprio(struct task_struct *p)
4105 {
4106         return avc_has_perm(&selinux_state,
4107                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4108                             PROCESS__GETSCHED, NULL);
4109 }
4110
4111 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4112                                 unsigned int flags)
4113 {
4114         u32 av = 0;
4115
4116         if (!flags)
4117                 return 0;
4118         if (flags & LSM_PRLIMIT_WRITE)
4119                 av |= PROCESS__SETRLIMIT;
4120         if (flags & LSM_PRLIMIT_READ)
4121                 av |= PROCESS__GETRLIMIT;
4122         return avc_has_perm(&selinux_state,
4123                             cred_sid(cred), cred_sid(tcred),
4124                             SECCLASS_PROCESS, av, NULL);
4125 }
4126
4127 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4128                 struct rlimit *new_rlim)
4129 {
4130         struct rlimit *old_rlim = p->signal->rlim + resource;
4131
4132         /* Control the ability to change the hard limit (whether
4133            lowering or raising it), so that the hard limit can
4134            later be used as a safe reset point for the soft limit
4135            upon context transitions.  See selinux_bprm_committing_creds. */
4136         if (old_rlim->rlim_max != new_rlim->rlim_max)
4137                 return avc_has_perm(&selinux_state,
4138                                     current_sid(), task_sid(p),
4139                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4140
4141         return 0;
4142 }
4143
4144 static int selinux_task_setscheduler(struct task_struct *p)
4145 {
4146         return avc_has_perm(&selinux_state,
4147                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4148                             PROCESS__SETSCHED, NULL);
4149 }
4150
4151 static int selinux_task_getscheduler(struct task_struct *p)
4152 {
4153         return avc_has_perm(&selinux_state,
4154                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4155                             PROCESS__GETSCHED, NULL);
4156 }
4157
4158 static int selinux_task_movememory(struct task_struct *p)
4159 {
4160         return avc_has_perm(&selinux_state,
4161                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4162                             PROCESS__SETSCHED, NULL);
4163 }
4164
4165 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
4166                                 int sig, const struct cred *cred)
4167 {
4168         u32 secid;
4169         u32 perm;
4170
4171         if (!sig)
4172                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4173         else
4174                 perm = signal_to_av(sig);
4175         if (!cred)
4176                 secid = current_sid();
4177         else
4178                 secid = cred_sid(cred);
4179         return avc_has_perm(&selinux_state,
4180                             secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4181 }
4182
4183 static void selinux_task_to_inode(struct task_struct *p,
4184                                   struct inode *inode)
4185 {
4186         struct inode_security_struct *isec = inode->i_security;
4187         u32 sid = task_sid(p);
4188
4189         spin_lock(&isec->lock);
4190         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4191         isec->sid = sid;
4192         isec->initialized = LABEL_INITIALIZED;
4193         spin_unlock(&isec->lock);
4194 }
4195
4196 /* Returns error only if unable to parse addresses */
4197 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4198                         struct common_audit_data *ad, u8 *proto)
4199 {
4200         int offset, ihlen, ret = -EINVAL;
4201         struct iphdr _iph, *ih;
4202
4203         offset = skb_network_offset(skb);
4204         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4205         if (ih == NULL)
4206                 goto out;
4207
4208         ihlen = ih->ihl * 4;
4209         if (ihlen < sizeof(_iph))
4210                 goto out;
4211
4212         ad->u.net->v4info.saddr = ih->saddr;
4213         ad->u.net->v4info.daddr = ih->daddr;
4214         ret = 0;
4215
4216         if (proto)
4217                 *proto = ih->protocol;
4218
4219         switch (ih->protocol) {
4220         case IPPROTO_TCP: {
4221                 struct tcphdr _tcph, *th;
4222
4223                 if (ntohs(ih->frag_off) & IP_OFFSET)
4224                         break;
4225
4226                 offset += ihlen;
4227                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4228                 if (th == NULL)
4229                         break;
4230
4231                 ad->u.net->sport = th->source;
4232                 ad->u.net->dport = th->dest;
4233                 break;
4234         }
4235
4236         case IPPROTO_UDP: {
4237                 struct udphdr _udph, *uh;
4238
4239                 if (ntohs(ih->frag_off) & IP_OFFSET)
4240                         break;
4241
4242                 offset += ihlen;
4243                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4244                 if (uh == NULL)
4245                         break;
4246
4247                 ad->u.net->sport = uh->source;
4248                 ad->u.net->dport = uh->dest;
4249                 break;
4250         }
4251
4252         case IPPROTO_DCCP: {
4253                 struct dccp_hdr _dccph, *dh;
4254
4255                 if (ntohs(ih->frag_off) & IP_OFFSET)
4256                         break;
4257
4258                 offset += ihlen;
4259                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4260                 if (dh == NULL)
4261                         break;
4262
4263                 ad->u.net->sport = dh->dccph_sport;
4264                 ad->u.net->dport = dh->dccph_dport;
4265                 break;
4266         }
4267
4268 #if IS_ENABLED(CONFIG_IP_SCTP)
4269         case IPPROTO_SCTP: {
4270                 struct sctphdr _sctph, *sh;
4271
4272                 if (ntohs(ih->frag_off) & IP_OFFSET)
4273                         break;
4274
4275                 offset += ihlen;
4276                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4277                 if (sh == NULL)
4278                         break;
4279
4280                 ad->u.net->sport = sh->source;
4281                 ad->u.net->dport = sh->dest;
4282                 break;
4283         }
4284 #endif
4285         default:
4286                 break;
4287         }
4288 out:
4289         return ret;
4290 }
4291
4292 #if IS_ENABLED(CONFIG_IPV6)
4293
4294 /* Returns error only if unable to parse addresses */
4295 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4296                         struct common_audit_data *ad, u8 *proto)
4297 {
4298         u8 nexthdr;
4299         int ret = -EINVAL, offset;
4300         struct ipv6hdr _ipv6h, *ip6;
4301         __be16 frag_off;
4302
4303         offset = skb_network_offset(skb);
4304         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4305         if (ip6 == NULL)
4306                 goto out;
4307
4308         ad->u.net->v6info.saddr = ip6->saddr;
4309         ad->u.net->v6info.daddr = ip6->daddr;
4310         ret = 0;
4311
4312         nexthdr = ip6->nexthdr;
4313         offset += sizeof(_ipv6h);
4314         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4315         if (offset < 0)
4316                 goto out;
4317
4318         if (proto)
4319                 *proto = nexthdr;
4320
4321         switch (nexthdr) {
4322         case IPPROTO_TCP: {
4323                 struct tcphdr _tcph, *th;
4324
4325                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4326                 if (th == NULL)
4327                         break;
4328
4329                 ad->u.net->sport = th->source;
4330                 ad->u.net->dport = th->dest;
4331                 break;
4332         }
4333
4334         case IPPROTO_UDP: {
4335                 struct udphdr _udph, *uh;
4336
4337                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4338                 if (uh == NULL)
4339                         break;
4340
4341                 ad->u.net->sport = uh->source;
4342                 ad->u.net->dport = uh->dest;
4343                 break;
4344         }
4345
4346         case IPPROTO_DCCP: {
4347                 struct dccp_hdr _dccph, *dh;
4348
4349                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4350                 if (dh == NULL)
4351                         break;
4352
4353                 ad->u.net->sport = dh->dccph_sport;
4354                 ad->u.net->dport = dh->dccph_dport;
4355                 break;
4356         }
4357
4358 #if IS_ENABLED(CONFIG_IP_SCTP)
4359         case IPPROTO_SCTP: {
4360                 struct sctphdr _sctph, *sh;
4361
4362                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4363                 if (sh == NULL)
4364                         break;
4365
4366                 ad->u.net->sport = sh->source;
4367                 ad->u.net->dport = sh->dest;
4368                 break;
4369         }
4370 #endif
4371         /* includes fragments */
4372         default:
4373                 break;
4374         }
4375 out:
4376         return ret;
4377 }
4378
4379 #endif /* IPV6 */
4380
4381 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4382                              char **_addrp, int src, u8 *proto)
4383 {
4384         char *addrp;
4385         int ret;
4386
4387         switch (ad->u.net->family) {
4388         case PF_INET:
4389                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4390                 if (ret)
4391                         goto parse_error;
4392                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4393                                        &ad->u.net->v4info.daddr);
4394                 goto okay;
4395
4396 #if IS_ENABLED(CONFIG_IPV6)
4397         case PF_INET6:
4398                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4399                 if (ret)
4400                         goto parse_error;
4401                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4402                                        &ad->u.net->v6info.daddr);
4403                 goto okay;
4404 #endif  /* IPV6 */
4405         default:
4406                 addrp = NULL;
4407                 goto okay;
4408         }
4409
4410 parse_error:
4411         printk(KERN_WARNING
4412                "SELinux: failure in selinux_parse_skb(),"
4413                " unable to parse packet\n");
4414         return ret;
4415
4416 okay:
4417         if (_addrp)
4418                 *_addrp = addrp;
4419         return 0;
4420 }
4421
4422 /**
4423  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4424  * @skb: the packet
4425  * @family: protocol family
4426  * @sid: the packet's peer label SID
4427  *
4428  * Description:
4429  * Check the various different forms of network peer labeling and determine
4430  * the peer label/SID for the packet; most of the magic actually occurs in
4431  * the security server function security_net_peersid_cmp().  The function
4432  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4433  * or -EACCES if @sid is invalid due to inconsistencies with the different
4434  * peer labels.
4435  *
4436  */
4437 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4438 {
4439         int err;
4440         u32 xfrm_sid;
4441         u32 nlbl_sid;
4442         u32 nlbl_type;
4443
4444         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4445         if (unlikely(err))
4446                 return -EACCES;
4447         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4448         if (unlikely(err))
4449                 return -EACCES;
4450
4451         err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4452                                            nlbl_type, xfrm_sid, sid);
4453         if (unlikely(err)) {
4454                 printk(KERN_WARNING
4455                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4456                        " unable to determine packet's peer label\n");
4457                 return -EACCES;
4458         }
4459
4460         return 0;
4461 }
4462
4463 /**
4464  * selinux_conn_sid - Determine the child socket label for a connection
4465  * @sk_sid: the parent socket's SID
4466  * @skb_sid: the packet's SID
4467  * @conn_sid: the resulting connection SID
4468  *
4469  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4470  * combined with the MLS information from @skb_sid in order to create
4471  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4472  * of @sk_sid.  Returns zero on success, negative values on failure.
4473  *
4474  */
4475 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4476 {
4477         int err = 0;
4478
4479         if (skb_sid != SECSID_NULL)
4480                 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4481                                             conn_sid);
4482         else
4483                 *conn_sid = sk_sid;
4484
4485         return err;
4486 }
4487
4488 /* socket security operations */
4489
4490 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4491                                  u16 secclass, u32 *socksid)
4492 {
4493         if (tsec->sockcreate_sid > SECSID_NULL) {
4494                 *socksid = tsec->sockcreate_sid;
4495                 return 0;
4496         }
4497
4498         return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4499                                        secclass, NULL, socksid);
4500 }
4501
4502 static int sock_has_perm(struct sock *sk, u32 perms)
4503 {
4504         struct sk_security_struct *sksec = sk->sk_security;
4505         struct common_audit_data ad;
4506         struct lsm_network_audit net = {0,};
4507
4508         if (sksec->sid == SECINITSID_KERNEL)
4509                 return 0;
4510
4511         ad.type = LSM_AUDIT_DATA_NET;
4512         ad.u.net = &net;
4513         ad.u.net->sk = sk;
4514
4515         return avc_has_perm(&selinux_state,
4516                             current_sid(), sksec->sid, sksec->sclass, perms,
4517                             &ad);
4518 }
4519
4520 static int selinux_socket_create(int family, int type,
4521                                  int protocol, int kern)
4522 {
4523         const struct task_security_struct *tsec = current_security();
4524         u32 newsid;
4525         u16 secclass;
4526         int rc;
4527
4528         if (kern)
4529                 return 0;
4530
4531         secclass = socket_type_to_security_class(family, type, protocol);
4532         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4533         if (rc)
4534                 return rc;
4535
4536         return avc_has_perm(&selinux_state,
4537                             tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4538 }
4539
4540 static int selinux_socket_post_create(struct socket *sock, int family,
4541                                       int type, int protocol, int kern)
4542 {
4543         const struct task_security_struct *tsec = current_security();
4544         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4545         struct sk_security_struct *sksec;
4546         u16 sclass = socket_type_to_security_class(family, type, protocol);
4547         u32 sid = SECINITSID_KERNEL;
4548         int err = 0;
4549
4550         if (!kern) {
4551                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4552                 if (err)
4553                         return err;
4554         }
4555
4556         isec->sclass = sclass;
4557         isec->sid = sid;
4558         isec->initialized = LABEL_INITIALIZED;
4559
4560         if (sock->sk) {
4561                 sksec = sock->sk->sk_security;
4562                 sksec->sclass = sclass;
4563                 sksec->sid = sid;
4564                 /* Allows detection of the first association on this socket */
4565                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4566                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4567
4568                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4569         }
4570
4571         return err;
4572 }
4573
4574 /* Range of port numbers used to automatically bind.
4575    Need to determine whether we should perform a name_bind
4576    permission check between the socket and the port number. */
4577
4578 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4579 {
4580         struct sock *sk = sock->sk;
4581         u16 family;
4582         int err;
4583
4584         err = sock_has_perm(sk, SOCKET__BIND);
4585         if (err)
4586                 goto out;
4587
4588         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4589         family = sk->sk_family;
4590         if (family == PF_INET || family == PF_INET6) {
4591                 char *addrp;
4592                 struct sk_security_struct *sksec = sk->sk_security;
4593                 struct common_audit_data ad;
4594                 struct lsm_network_audit net = {0,};
4595                 struct sockaddr_in *addr4 = NULL;
4596                 struct sockaddr_in6 *addr6 = NULL;
4597                 unsigned short snum;
4598                 u32 sid, node_perm;
4599
4600                 /*
4601                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4602                  * that validates multiple binding addresses. Because of this
4603                  * need to check address->sa_family as it is possible to have
4604                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4605                  */
4606                 switch (address->sa_family) {
4607                 case AF_INET:
4608                         if (addrlen < sizeof(struct sockaddr_in))
4609                                 return -EINVAL;
4610                         addr4 = (struct sockaddr_in *)address;
4611                         snum = ntohs(addr4->sin_port);
4612                         addrp = (char *)&addr4->sin_addr.s_addr;
4613                         break;
4614                 case AF_INET6:
4615                         if (addrlen < SIN6_LEN_RFC2133)
4616                                 return -EINVAL;
4617                         addr6 = (struct sockaddr_in6 *)address;
4618                         snum = ntohs(addr6->sin6_port);
4619                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4620                         break;
4621                 default:
4622                         /* Note that SCTP services expect -EINVAL, whereas
4623                          * others expect -EAFNOSUPPORT.
4624                          */
4625                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4626                                 return -EINVAL;
4627                         else
4628                                 return -EAFNOSUPPORT;
4629                 }
4630
4631                 if (snum) {
4632                         int low, high;
4633
4634                         inet_get_local_port_range(sock_net(sk), &low, &high);
4635
4636                         if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
4637                             snum > high) {
4638                                 err = sel_netport_sid(sk->sk_protocol,
4639                                                       snum, &sid);
4640                                 if (err)
4641                                         goto out;
4642                                 ad.type = LSM_AUDIT_DATA_NET;
4643                                 ad.u.net = &net;
4644                                 ad.u.net->sport = htons(snum);
4645                                 ad.u.net->family = family;
4646                                 err = avc_has_perm(&selinux_state,
4647                                                    sksec->sid, sid,
4648                                                    sksec->sclass,
4649                                                    SOCKET__NAME_BIND, &ad);
4650                                 if (err)
4651                                         goto out;
4652                         }
4653                 }
4654
4655                 switch (sksec->sclass) {
4656                 case SECCLASS_TCP_SOCKET:
4657                         node_perm = TCP_SOCKET__NODE_BIND;
4658                         break;
4659
4660                 case SECCLASS_UDP_SOCKET:
4661                         node_perm = UDP_SOCKET__NODE_BIND;
4662                         break;
4663
4664                 case SECCLASS_DCCP_SOCKET:
4665                         node_perm = DCCP_SOCKET__NODE_BIND;
4666                         break;
4667
4668                 case SECCLASS_SCTP_SOCKET:
4669                         node_perm = SCTP_SOCKET__NODE_BIND;
4670                         break;
4671
4672                 default:
4673                         node_perm = RAWIP_SOCKET__NODE_BIND;
4674                         break;
4675                 }
4676
4677                 err = sel_netnode_sid(addrp, family, &sid);
4678                 if (err)
4679                         goto out;
4680
4681                 ad.type = LSM_AUDIT_DATA_NET;
4682                 ad.u.net = &net;
4683                 ad.u.net->sport = htons(snum);
4684                 ad.u.net->family = family;
4685
4686                 if (address->sa_family == AF_INET)
4687                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4688                 else
4689                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4690
4691                 err = avc_has_perm(&selinux_state,
4692                                    sksec->sid, sid,
4693                                    sksec->sclass, node_perm, &ad);
4694                 if (err)
4695                         goto out;
4696         }
4697 out:
4698         return err;
4699 }
4700
4701 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4702  * and sctp_sendmsg(3) as described in Documentation/security/LSM-sctp.txt
4703  */
4704 static int selinux_socket_connect_helper(struct socket *sock,
4705                                          struct sockaddr *address, int addrlen)
4706 {
4707         struct sock *sk = sock->sk;
4708         struct sk_security_struct *sksec = sk->sk_security;
4709         int err;
4710
4711         err = sock_has_perm(sk, SOCKET__CONNECT);
4712         if (err)
4713                 return err;
4714
4715         /*
4716          * If a TCP, DCCP or SCTP socket, check name_connect permission
4717          * for the port.
4718          */
4719         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4720             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4721             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4722                 struct common_audit_data ad;
4723                 struct lsm_network_audit net = {0,};
4724                 struct sockaddr_in *addr4 = NULL;
4725                 struct sockaddr_in6 *addr6 = NULL;
4726                 unsigned short snum;
4727                 u32 sid, perm;
4728
4729                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4730                  * that validates multiple connect addresses. Because of this
4731                  * need to check address->sa_family as it is possible to have
4732                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4733                  */
4734                 switch (address->sa_family) {
4735                 case AF_INET:
4736                         addr4 = (struct sockaddr_in *)address;
4737                         if (addrlen < sizeof(struct sockaddr_in))
4738                                 return -EINVAL;
4739                         snum = ntohs(addr4->sin_port);
4740                         break;
4741                 case AF_INET6:
4742                         addr6 = (struct sockaddr_in6 *)address;
4743                         if (addrlen < SIN6_LEN_RFC2133)
4744                                 return -EINVAL;
4745                         snum = ntohs(addr6->sin6_port);
4746                         break;
4747                 default:
4748                         /* Note that SCTP services expect -EINVAL, whereas
4749                          * others expect -EAFNOSUPPORT.
4750                          */
4751                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4752                                 return -EINVAL;
4753                         else
4754                                 return -EAFNOSUPPORT;
4755                 }
4756
4757                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4758                 if (err)
4759                         return err;
4760
4761                 switch (sksec->sclass) {
4762                 case SECCLASS_TCP_SOCKET:
4763                         perm = TCP_SOCKET__NAME_CONNECT;
4764                         break;
4765                 case SECCLASS_DCCP_SOCKET:
4766                         perm = DCCP_SOCKET__NAME_CONNECT;
4767                         break;
4768                 case SECCLASS_SCTP_SOCKET:
4769                         perm = SCTP_SOCKET__NAME_CONNECT;
4770                         break;
4771                 }
4772
4773                 ad.type = LSM_AUDIT_DATA_NET;
4774                 ad.u.net = &net;
4775                 ad.u.net->dport = htons(snum);
4776                 ad.u.net->family = sk->sk_family;
4777                 err = avc_has_perm(&selinux_state,
4778                                    sksec->sid, sid, sksec->sclass, perm, &ad);
4779                 if (err)
4780                         return err;
4781         }
4782
4783         return 0;
4784 }
4785
4786 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4787 static int selinux_socket_connect(struct socket *sock,
4788                                   struct sockaddr *address, int addrlen)
4789 {
4790         int err;
4791         struct sock *sk = sock->sk;
4792
4793         err = selinux_socket_connect_helper(sock, address, addrlen);
4794         if (err)
4795                 return err;
4796
4797         return selinux_netlbl_socket_connect(sk, address);
4798 }
4799
4800 static int selinux_socket_listen(struct socket *sock, int backlog)
4801 {
4802         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4803 }
4804
4805 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4806 {
4807         int err;
4808         struct inode_security_struct *isec;
4809         struct inode_security_struct *newisec;
4810         u16 sclass;
4811         u32 sid;
4812
4813         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4814         if (err)
4815                 return err;
4816
4817         isec = inode_security_novalidate(SOCK_INODE(sock));
4818         spin_lock(&isec->lock);
4819         sclass = isec->sclass;
4820         sid = isec->sid;
4821         spin_unlock(&isec->lock);
4822
4823         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4824         newisec->sclass = sclass;
4825         newisec->sid = sid;
4826         newisec->initialized = LABEL_INITIALIZED;
4827
4828         return 0;
4829 }
4830
4831 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4832                                   int size)
4833 {
4834         return sock_has_perm(sock->sk, SOCKET__WRITE);
4835 }
4836
4837 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4838                                   int size, int flags)
4839 {
4840         return sock_has_perm(sock->sk, SOCKET__READ);
4841 }
4842
4843 static int selinux_socket_getsockname(struct socket *sock)
4844 {
4845         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4846 }
4847
4848 static int selinux_socket_getpeername(struct socket *sock)
4849 {
4850         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4851 }
4852
4853 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4854 {
4855         int err;
4856
4857         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4858         if (err)
4859                 return err;
4860
4861         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4862 }
4863
4864 static int selinux_socket_getsockopt(struct socket *sock, int level,
4865                                      int optname)
4866 {
4867         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4868 }
4869
4870 static int selinux_socket_shutdown(struct socket *sock, int how)
4871 {
4872         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4873 }
4874
4875 static int selinux_socket_unix_stream_connect(struct sock *sock,
4876                                               struct sock *other,
4877                                               struct sock *newsk)
4878 {
4879         struct sk_security_struct *sksec_sock = sock->sk_security;
4880         struct sk_security_struct *sksec_other = other->sk_security;
4881         struct sk_security_struct *sksec_new = newsk->sk_security;
4882         struct common_audit_data ad;
4883         struct lsm_network_audit net = {0,};
4884         int err;
4885
4886         ad.type = LSM_AUDIT_DATA_NET;
4887         ad.u.net = &net;
4888         ad.u.net->sk = other;
4889
4890         err = avc_has_perm(&selinux_state,
4891                            sksec_sock->sid, sksec_other->sid,
4892                            sksec_other->sclass,
4893                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4894         if (err)
4895                 return err;
4896
4897         /* server child socket */
4898         sksec_new->peer_sid = sksec_sock->sid;
4899         err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4900                                     sksec_sock->sid, &sksec_new->sid);
4901         if (err)
4902                 return err;
4903
4904         /* connecting socket */
4905         sksec_sock->peer_sid = sksec_new->sid;
4906
4907         return 0;
4908 }
4909
4910 static int selinux_socket_unix_may_send(struct socket *sock,
4911                                         struct socket *other)
4912 {
4913         struct sk_security_struct *ssec = sock->sk->sk_security;
4914         struct sk_security_struct *osec = other->sk->sk_security;
4915         struct common_audit_data ad;
4916         struct lsm_network_audit net = {0,};
4917
4918         ad.type = LSM_AUDIT_DATA_NET;
4919         ad.u.net = &net;
4920         ad.u.net->sk = other->sk;
4921
4922         return avc_has_perm(&selinux_state,
4923                             ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4924                             &ad);
4925 }
4926
4927 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4928                                     char *addrp, u16 family, u32 peer_sid,
4929                                     struct common_audit_data *ad)
4930 {
4931         int err;
4932         u32 if_sid;
4933         u32 node_sid;
4934
4935         err = sel_netif_sid(ns, ifindex, &if_sid);
4936         if (err)
4937                 return err;
4938         err = avc_has_perm(&selinux_state,
4939                            peer_sid, if_sid,
4940                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4941         if (err)
4942                 return err;
4943
4944         err = sel_netnode_sid(addrp, family, &node_sid);
4945         if (err)
4946                 return err;
4947         return avc_has_perm(&selinux_state,
4948                             peer_sid, node_sid,
4949                             SECCLASS_NODE, NODE__RECVFROM, ad);
4950 }
4951
4952 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4953                                        u16 family)
4954 {
4955         int err = 0;
4956         struct sk_security_struct *sksec = sk->sk_security;
4957         u32 sk_sid = sksec->sid;
4958         struct common_audit_data ad;
4959         struct lsm_network_audit net = {0,};
4960         char *addrp;
4961
4962         ad.type = LSM_AUDIT_DATA_NET;
4963         ad.u.net = &net;
4964         ad.u.net->netif = skb->skb_iif;
4965         ad.u.net->family = family;
4966         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4967         if (err)
4968                 return err;
4969
4970         if (selinux_secmark_enabled()) {
4971                 err = avc_has_perm(&selinux_state,
4972                                    sk_sid, skb->secmark, SECCLASS_PACKET,
4973                                    PACKET__RECV, &ad);
4974                 if (err)
4975                         return err;
4976         }
4977
4978         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4979         if (err)
4980                 return err;
4981         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4982
4983         return err;
4984 }
4985
4986 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4987 {
4988         int err;
4989         struct sk_security_struct *sksec = sk->sk_security;
4990         u16 family = sk->sk_family;
4991         u32 sk_sid = sksec->sid;
4992         struct common_audit_data ad;
4993         struct lsm_network_audit net = {0,};
4994         char *addrp;
4995         u8 secmark_active;
4996         u8 peerlbl_active;
4997
4998         if (family != PF_INET && family != PF_INET6)
4999                 return 0;
5000
5001         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5002         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5003                 family = PF_INET;
5004
5005         /* If any sort of compatibility mode is enabled then handoff processing
5006          * to the selinux_sock_rcv_skb_compat() function to deal with the
5007          * special handling.  We do this in an attempt to keep this function
5008          * as fast and as clean as possible. */
5009         if (!selinux_policycap_netpeer())
5010                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5011
5012         secmark_active = selinux_secmark_enabled();
5013         peerlbl_active = selinux_peerlbl_enabled();
5014         if (!secmark_active && !peerlbl_active)
5015                 return 0;
5016
5017         ad.type = LSM_AUDIT_DATA_NET;
5018         ad.u.net = &net;
5019         ad.u.net->netif = skb->skb_iif;
5020         ad.u.net->family = family;
5021         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5022         if (err)
5023                 return err;
5024
5025         if (peerlbl_active) {
5026                 u32 peer_sid;
5027
5028                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5029                 if (err)
5030                         return err;
5031                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5032                                                addrp, family, peer_sid, &ad);
5033                 if (err) {
5034                         selinux_netlbl_err(skb, family, err, 0);
5035                         return err;
5036                 }
5037                 err = avc_has_perm(&selinux_state,
5038                                    sk_sid, peer_sid, SECCLASS_PEER,
5039                                    PEER__RECV, &ad);
5040                 if (err) {
5041                         selinux_netlbl_err(skb, family, err, 0);
5042                         return err;
5043                 }
5044         }
5045
5046         if (secmark_active) {
5047                 err = avc_has_perm(&selinux_state,
5048                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5049                                    PACKET__RECV, &ad);
5050                 if (err)
5051                         return err;
5052         }
5053
5054         return err;
5055 }
5056
5057 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5058                                             int __user *optlen, unsigned len)
5059 {
5060         int err = 0;
5061         char *scontext;
5062         u32 scontext_len;
5063         struct sk_security_struct *sksec = sock->sk->sk_security;
5064         u32 peer_sid = SECSID_NULL;
5065
5066         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5067             sksec->sclass == SECCLASS_TCP_SOCKET ||
5068             sksec->sclass == SECCLASS_SCTP_SOCKET)
5069                 peer_sid = sksec->peer_sid;
5070         if (peer_sid == SECSID_NULL)
5071                 return -ENOPROTOOPT;
5072
5073         err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5074                                       &scontext_len);
5075         if (err)
5076                 return err;
5077
5078         if (scontext_len > len) {
5079                 err = -ERANGE;
5080                 goto out_len;
5081         }
5082
5083         if (copy_to_user(optval, scontext, scontext_len))
5084                 err = -EFAULT;
5085
5086 out_len:
5087         if (put_user(scontext_len, optlen))
5088                 err = -EFAULT;
5089         kfree(scontext);
5090         return err;
5091 }
5092
5093 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5094 {
5095         u32 peer_secid = SECSID_NULL;
5096         u16 family;
5097         struct inode_security_struct *isec;
5098
5099         if (skb && skb->protocol == htons(ETH_P_IP))
5100                 family = PF_INET;
5101         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5102                 family = PF_INET6;
5103         else if (sock)
5104                 family = sock->sk->sk_family;
5105         else
5106                 goto out;
5107
5108         if (sock && family == PF_UNIX) {
5109                 isec = inode_security_novalidate(SOCK_INODE(sock));
5110                 peer_secid = isec->sid;
5111         } else if (skb)
5112                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5113
5114 out:
5115         *secid = peer_secid;
5116         if (peer_secid == SECSID_NULL)
5117                 return -EINVAL;
5118         return 0;
5119 }
5120
5121 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5122 {
5123         struct sk_security_struct *sksec;
5124
5125         sksec = kzalloc(sizeof(*sksec), priority);
5126         if (!sksec)
5127                 return -ENOMEM;
5128
5129         sksec->peer_sid = SECINITSID_UNLABELED;
5130         sksec->sid = SECINITSID_UNLABELED;
5131         sksec->sclass = SECCLASS_SOCKET;
5132         selinux_netlbl_sk_security_reset(sksec);
5133         sk->sk_security = sksec;
5134
5135         return 0;
5136 }
5137
5138 static void selinux_sk_free_security(struct sock *sk)
5139 {
5140         struct sk_security_struct *sksec = sk->sk_security;
5141
5142         sk->sk_security = NULL;
5143         selinux_netlbl_sk_security_free(sksec);
5144         kfree(sksec);
5145 }
5146
5147 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5148 {
5149         struct sk_security_struct *sksec = sk->sk_security;
5150         struct sk_security_struct *newsksec = newsk->sk_security;
5151
5152         newsksec->sid = sksec->sid;
5153         newsksec->peer_sid = sksec->peer_sid;
5154         newsksec->sclass = sksec->sclass;
5155
5156         selinux_netlbl_sk_security_reset(newsksec);
5157 }
5158
5159 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5160 {
5161         if (!sk)
5162                 *secid = SECINITSID_ANY_SOCKET;
5163         else {
5164                 struct sk_security_struct *sksec = sk->sk_security;
5165
5166                 *secid = sksec->sid;
5167         }
5168 }
5169
5170 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5171 {
5172         struct inode_security_struct *isec =
5173                 inode_security_novalidate(SOCK_INODE(parent));
5174         struct sk_security_struct *sksec = sk->sk_security;
5175
5176         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5177             sk->sk_family == PF_UNIX)
5178                 isec->sid = sksec->sid;
5179         sksec->sclass = isec->sclass;
5180 }
5181
5182 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5183  * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5184  * already present).
5185  */
5186 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5187                                       struct sk_buff *skb)
5188 {
5189         struct sk_security_struct *sksec = ep->base.sk->sk_security;
5190         struct common_audit_data ad;
5191         struct lsm_network_audit net = {0,};
5192         u8 peerlbl_active;
5193         u32 peer_sid = SECINITSID_UNLABELED;
5194         u32 conn_sid;
5195         int err = 0;
5196
5197         if (!selinux_policycap_extsockclass())
5198                 return 0;
5199
5200         peerlbl_active = selinux_peerlbl_enabled();
5201
5202         if (peerlbl_active) {
5203                 /* This will return peer_sid = SECSID_NULL if there are
5204                  * no peer labels, see security_net_peersid_resolve().
5205                  */
5206                 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5207                                               &peer_sid);
5208                 if (err)
5209                         return err;
5210
5211                 if (peer_sid == SECSID_NULL)
5212                         peer_sid = SECINITSID_UNLABELED;
5213         }
5214
5215         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5216                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5217
5218                 /* Here as first association on socket. As the peer SID
5219                  * was allowed by peer recv (and the netif/node checks),
5220                  * then it is approved by policy and used as the primary
5221                  * peer SID for getpeercon(3).
5222                  */
5223                 sksec->peer_sid = peer_sid;
5224         } else if  (sksec->peer_sid != peer_sid) {
5225                 /* Other association peer SIDs are checked to enforce
5226                  * consistency among the peer SIDs.
5227                  */
5228                 ad.type = LSM_AUDIT_DATA_NET;
5229                 ad.u.net = &net;
5230                 ad.u.net->sk = ep->base.sk;
5231                 err = avc_has_perm(&selinux_state,
5232                                    sksec->peer_sid, peer_sid, sksec->sclass,
5233                                    SCTP_SOCKET__ASSOCIATION, &ad);
5234                 if (err)
5235                         return err;
5236         }
5237
5238         /* Compute the MLS component for the connection and store
5239          * the information in ep. This will be used by SCTP TCP type
5240          * sockets and peeled off connections as they cause a new
5241          * socket to be generated. selinux_sctp_sk_clone() will then
5242          * plug this into the new socket.
5243          */
5244         err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5245         if (err)
5246                 return err;
5247
5248         ep->secid = conn_sid;
5249         ep->peer_secid = peer_sid;
5250
5251         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5252         return selinux_netlbl_sctp_assoc_request(ep, skb);
5253 }
5254
5255 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5256  * based on their @optname.
5257  */
5258 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5259                                      struct sockaddr *address,
5260                                      int addrlen)
5261 {
5262         int len, err = 0, walk_size = 0;
5263         void *addr_buf;
5264         struct sockaddr *addr;
5265         struct socket *sock;
5266
5267         if (!selinux_policycap_extsockclass())
5268                 return 0;
5269
5270         /* Process one or more addresses that may be IPv4 or IPv6 */
5271         sock = sk->sk_socket;
5272         addr_buf = address;
5273
5274         while (walk_size < addrlen) {
5275                 addr = addr_buf;
5276                 switch (addr->sa_family) {
5277                 case AF_INET:
5278                         len = sizeof(struct sockaddr_in);
5279                         break;
5280                 case AF_INET6:
5281                         len = sizeof(struct sockaddr_in6);
5282                         break;
5283                 default:
5284                         return -EAFNOSUPPORT;
5285                 }
5286
5287                 err = -EINVAL;
5288                 switch (optname) {
5289                 /* Bind checks */
5290                 case SCTP_PRIMARY_ADDR:
5291                 case SCTP_SET_PEER_PRIMARY_ADDR:
5292                 case SCTP_SOCKOPT_BINDX_ADD:
5293                         err = selinux_socket_bind(sock, addr, len);
5294                         break;
5295                 /* Connect checks */
5296                 case SCTP_SOCKOPT_CONNECTX:
5297                 case SCTP_PARAM_SET_PRIMARY:
5298                 case SCTP_PARAM_ADD_IP:
5299                 case SCTP_SENDMSG_CONNECT:
5300                         err = selinux_socket_connect_helper(sock, addr, len);
5301                         if (err)
5302                                 return err;
5303
5304                         /* As selinux_sctp_bind_connect() is called by the
5305                          * SCTP protocol layer, the socket is already locked,
5306                          * therefore selinux_netlbl_socket_connect_locked() is
5307                          * is called here. The situations handled are:
5308                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5309                          * whenever a new IP address is added or when a new
5310                          * primary address is selected.
5311                          * Note that an SCTP connect(2) call happens before
5312                          * the SCTP protocol layer and is handled via
5313                          * selinux_socket_connect().
5314                          */
5315                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5316                         break;
5317                 }
5318
5319                 if (err)
5320                         return err;
5321
5322                 addr_buf += len;
5323                 walk_size += len;
5324         }
5325
5326         return 0;
5327 }
5328
5329 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5330 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5331                                   struct sock *newsk)
5332 {
5333         struct sk_security_struct *sksec = sk->sk_security;
5334         struct sk_security_struct *newsksec = newsk->sk_security;
5335
5336         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5337          * the non-sctp clone version.
5338          */
5339         if (!selinux_policycap_extsockclass())
5340                 return selinux_sk_clone_security(sk, newsk);
5341
5342         newsksec->sid = ep->secid;
5343         newsksec->peer_sid = ep->peer_secid;
5344         newsksec->sclass = sksec->sclass;
5345         selinux_netlbl_sctp_sk_clone(sk, newsk);
5346 }
5347
5348 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5349                                      struct request_sock *req)
5350 {
5351         struct sk_security_struct *sksec = sk->sk_security;
5352         int err;
5353         u16 family = req->rsk_ops->family;
5354         u32 connsid;
5355         u32 peersid;
5356
5357         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5358         if (err)
5359                 return err;
5360         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5361         if (err)
5362                 return err;
5363         req->secid = connsid;
5364         req->peer_secid = peersid;
5365
5366         return selinux_netlbl_inet_conn_request(req, family);
5367 }
5368
5369 static void selinux_inet_csk_clone(struct sock *newsk,
5370                                    const struct request_sock *req)
5371 {
5372         struct sk_security_struct *newsksec = newsk->sk_security;
5373
5374         newsksec->sid = req->secid;
5375         newsksec->peer_sid = req->peer_secid;
5376         /* NOTE: Ideally, we should also get the isec->sid for the
5377            new socket in sync, but we don't have the isec available yet.
5378            So we will wait until sock_graft to do it, by which
5379            time it will have been created and available. */
5380
5381         /* We don't need to take any sort of lock here as we are the only
5382          * thread with access to newsksec */
5383         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5384 }
5385
5386 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5387 {
5388         u16 family = sk->sk_family;
5389         struct sk_security_struct *sksec = sk->sk_security;
5390
5391         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5392         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5393                 family = PF_INET;
5394
5395         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5396 }
5397
5398 static int selinux_secmark_relabel_packet(u32 sid)
5399 {
5400         const struct task_security_struct *__tsec;
5401         u32 tsid;
5402
5403         __tsec = current_security();
5404         tsid = __tsec->sid;
5405
5406         return avc_has_perm(&selinux_state,
5407                             tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5408                             NULL);
5409 }
5410
5411 static void selinux_secmark_refcount_inc(void)
5412 {
5413         atomic_inc(&selinux_secmark_refcount);
5414 }
5415
5416 static void selinux_secmark_refcount_dec(void)
5417 {
5418         atomic_dec(&selinux_secmark_refcount);
5419 }
5420
5421 static void selinux_req_classify_flow(const struct request_sock *req,
5422                                       struct flowi *fl)
5423 {
5424         fl->flowi_secid = req->secid;
5425 }
5426
5427 static int selinux_tun_dev_alloc_security(void **security)
5428 {
5429         struct tun_security_struct *tunsec;
5430
5431         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5432         if (!tunsec)
5433                 return -ENOMEM;
5434         tunsec->sid = current_sid();
5435
5436         *security = tunsec;
5437         return 0;
5438 }
5439
5440 static void selinux_tun_dev_free_security(void *security)
5441 {
5442         kfree(security);
5443 }
5444
5445 static int selinux_tun_dev_create(void)
5446 {
5447         u32 sid = current_sid();
5448
5449         /* we aren't taking into account the "sockcreate" SID since the socket
5450          * that is being created here is not a socket in the traditional sense,
5451          * instead it is a private sock, accessible only to the kernel, and
5452          * representing a wide range of network traffic spanning multiple
5453          * connections unlike traditional sockets - check the TUN driver to
5454          * get a better understanding of why this socket is special */
5455
5456         return avc_has_perm(&selinux_state,
5457                             sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5458                             NULL);
5459 }
5460
5461 static int selinux_tun_dev_attach_queue(void *security)
5462 {
5463         struct tun_security_struct *tunsec = security;
5464
5465         return avc_has_perm(&selinux_state,
5466                             current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5467                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5468 }
5469
5470 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5471 {
5472         struct tun_security_struct *tunsec = security;
5473         struct sk_security_struct *sksec = sk->sk_security;
5474
5475         /* we don't currently perform any NetLabel based labeling here and it
5476          * isn't clear that we would want to do so anyway; while we could apply
5477          * labeling without the support of the TUN user the resulting labeled
5478          * traffic from the other end of the connection would almost certainly
5479          * cause confusion to the TUN user that had no idea network labeling
5480          * protocols were being used */
5481
5482         sksec->sid = tunsec->sid;
5483         sksec->sclass = SECCLASS_TUN_SOCKET;
5484
5485         return 0;
5486 }
5487
5488 static int selinux_tun_dev_open(void *security)
5489 {
5490         struct tun_security_struct *tunsec = security;
5491         u32 sid = current_sid();
5492         int err;
5493
5494         err = avc_has_perm(&selinux_state,
5495                            sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5496                            TUN_SOCKET__RELABELFROM, NULL);
5497         if (err)
5498                 return err;
5499         err = avc_has_perm(&selinux_state,
5500                            sid, sid, SECCLASS_TUN_SOCKET,
5501                            TUN_SOCKET__RELABELTO, NULL);
5502         if (err)
5503                 return err;
5504         tunsec->sid = sid;
5505
5506         return 0;
5507 }
5508
5509 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5510 {
5511         int err = 0;
5512         u32 perm;
5513         struct nlmsghdr *nlh;
5514         struct sk_security_struct *sksec = sk->sk_security;
5515
5516         if (skb->len < NLMSG_HDRLEN) {
5517                 err = -EINVAL;
5518                 goto out;
5519         }
5520         nlh = nlmsg_hdr(skb);
5521
5522         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5523         if (err) {
5524                 if (err == -EINVAL) {
5525                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5526                                " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5527                                " pig=%d comm=%s\n",
5528                                sk->sk_protocol, nlh->nlmsg_type,
5529                                secclass_map[sksec->sclass - 1].name,
5530                                task_pid_nr(current), current->comm);
5531                         if (!enforcing_enabled(&selinux_state) ||
5532                             security_get_allow_unknown(&selinux_state))
5533                                 err = 0;
5534                 }
5535
5536                 /* Ignore */
5537                 if (err == -ENOENT)
5538                         err = 0;
5539                 goto out;
5540         }
5541
5542         err = sock_has_perm(sk, perm);
5543 out:
5544         return err;
5545 }
5546
5547 #ifdef CONFIG_NETFILTER
5548
5549 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5550                                        const struct net_device *indev,
5551                                        u16 family)
5552 {
5553         int err;
5554         char *addrp;
5555         u32 peer_sid;
5556         struct common_audit_data ad;
5557         struct lsm_network_audit net = {0,};
5558         u8 secmark_active;
5559         u8 netlbl_active;
5560         u8 peerlbl_active;
5561
5562         if (!selinux_policycap_netpeer())
5563                 return NF_ACCEPT;
5564
5565         secmark_active = selinux_secmark_enabled();
5566         netlbl_active = netlbl_enabled();
5567         peerlbl_active = selinux_peerlbl_enabled();
5568         if (!secmark_active && !peerlbl_active)
5569                 return NF_ACCEPT;
5570
5571         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5572                 return NF_DROP;
5573
5574         ad.type = LSM_AUDIT_DATA_NET;
5575         ad.u.net = &net;
5576         ad.u.net->netif = indev->ifindex;
5577         ad.u.net->family = family;
5578         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5579                 return NF_DROP;
5580
5581         if (peerlbl_active) {
5582                 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5583                                                addrp, family, peer_sid, &ad);
5584                 if (err) {
5585                         selinux_netlbl_err(skb, family, err, 1);
5586                         return NF_DROP;
5587                 }
5588         }
5589
5590         if (secmark_active)
5591                 if (avc_has_perm(&selinux_state,
5592                                  peer_sid, skb->secmark,
5593                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5594                         return NF_DROP;
5595
5596         if (netlbl_active)
5597                 /* we do this in the FORWARD path and not the POST_ROUTING
5598                  * path because we want to make sure we apply the necessary
5599                  * labeling before IPsec is applied so we can leverage AH
5600                  * protection */
5601                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5602                         return NF_DROP;
5603
5604         return NF_ACCEPT;
5605 }
5606
5607 static unsigned int selinux_ipv4_forward(void *priv,
5608                                          struct sk_buff *skb,
5609                                          const struct nf_hook_state *state)
5610 {
5611         return selinux_ip_forward(skb, state->in, PF_INET);
5612 }
5613
5614 #if IS_ENABLED(CONFIG_IPV6)
5615 static unsigned int selinux_ipv6_forward(void *priv,
5616                                          struct sk_buff *skb,
5617                                          const struct nf_hook_state *state)
5618 {
5619         return selinux_ip_forward(skb, state->in, PF_INET6);
5620 }
5621 #endif  /* IPV6 */
5622
5623 static unsigned int selinux_ip_output(struct sk_buff *skb,
5624                                       u16 family)
5625 {
5626         struct sock *sk;
5627         u32 sid;
5628
5629         if (!netlbl_enabled())
5630                 return NF_ACCEPT;
5631
5632         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5633          * because we want to make sure we apply the necessary labeling
5634          * before IPsec is applied so we can leverage AH protection */
5635         sk = skb->sk;
5636         if (sk) {
5637                 struct sk_security_struct *sksec;
5638
5639                 if (sk_listener(sk))
5640                         /* if the socket is the listening state then this
5641                          * packet is a SYN-ACK packet which means it needs to
5642                          * be labeled based on the connection/request_sock and
5643                          * not the parent socket.  unfortunately, we can't
5644                          * lookup the request_sock yet as it isn't queued on
5645                          * the parent socket until after the SYN-ACK is sent.
5646                          * the "solution" is to simply pass the packet as-is
5647                          * as any IP option based labeling should be copied
5648                          * from the initial connection request (in the IP
5649                          * layer).  it is far from ideal, but until we get a
5650                          * security label in the packet itself this is the
5651                          * best we can do. */
5652                         return NF_ACCEPT;
5653
5654                 /* standard practice, label using the parent socket */
5655                 sksec = sk->sk_security;
5656                 sid = sksec->sid;
5657         } else
5658                 sid = SECINITSID_KERNEL;
5659         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5660                 return NF_DROP;
5661
5662         return NF_ACCEPT;
5663 }
5664
5665 static unsigned int selinux_ipv4_output(void *priv,
5666                                         struct sk_buff *skb,
5667                                         const struct nf_hook_state *state)
5668 {
5669         return selinux_ip_output(skb, PF_INET);
5670 }
5671
5672 #if IS_ENABLED(CONFIG_IPV6)
5673 static unsigned int selinux_ipv6_output(void *priv,
5674                                         struct sk_buff *skb,
5675                                         const struct nf_hook_state *state)
5676 {
5677         return selinux_ip_output(skb, PF_INET6);
5678 }
5679 #endif  /* IPV6 */
5680
5681 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5682                                                 int ifindex,
5683                                                 u16 family)
5684 {
5685         struct sock *sk = skb_to_full_sk(skb);
5686         struct sk_security_struct *sksec;
5687         struct common_audit_data ad;
5688         struct lsm_network_audit net = {0,};
5689         char *addrp;
5690         u8 proto;
5691
5692         if (sk == NULL)
5693                 return NF_ACCEPT;
5694         sksec = sk->sk_security;
5695
5696         ad.type = LSM_AUDIT_DATA_NET;
5697         ad.u.net = &net;
5698         ad.u.net->netif = ifindex;
5699         ad.u.net->family = family;
5700         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5701                 return NF_DROP;
5702
5703         if (selinux_secmark_enabled())
5704                 if (avc_has_perm(&selinux_state,
5705                                  sksec->sid, skb->secmark,
5706                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5707                         return NF_DROP_ERR(-ECONNREFUSED);
5708
5709         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5710                 return NF_DROP_ERR(-ECONNREFUSED);
5711
5712         return NF_ACCEPT;
5713 }
5714
5715 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5716                                          const struct net_device *outdev,
5717                                          u16 family)
5718 {
5719         u32 secmark_perm;
5720         u32 peer_sid;
5721         int ifindex = outdev->ifindex;
5722         struct sock *sk;
5723         struct common_audit_data ad;
5724         struct lsm_network_audit net = {0,};
5725         char *addrp;
5726         u8 secmark_active;
5727         u8 peerlbl_active;
5728
5729         /* If any sort of compatibility mode is enabled then handoff processing
5730          * to the selinux_ip_postroute_compat() function to deal with the
5731          * special handling.  We do this in an attempt to keep this function
5732          * as fast and as clean as possible. */
5733         if (!selinux_policycap_netpeer())
5734                 return selinux_ip_postroute_compat(skb, ifindex, family);
5735
5736         secmark_active = selinux_secmark_enabled();
5737         peerlbl_active = selinux_peerlbl_enabled();
5738         if (!secmark_active && !peerlbl_active)
5739                 return NF_ACCEPT;
5740
5741         sk = skb_to_full_sk(skb);
5742
5743 #ifdef CONFIG_XFRM
5744         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5745          * packet transformation so allow the packet to pass without any checks
5746          * since we'll have another chance to perform access control checks
5747          * when the packet is on it's final way out.
5748          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5749          *       is NULL, in this case go ahead and apply access control.
5750          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5751          *       TCP listening state we cannot wait until the XFRM processing
5752          *       is done as we will miss out on the SA label if we do;
5753          *       unfortunately, this means more work, but it is only once per
5754          *       connection. */
5755         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5756             !(sk && sk_listener(sk)))
5757                 return NF_ACCEPT;
5758 #endif
5759
5760         if (sk == NULL) {
5761                 /* Without an associated socket the packet is either coming
5762                  * from the kernel or it is being forwarded; check the packet
5763                  * to determine which and if the packet is being forwarded
5764                  * query the packet directly to determine the security label. */
5765                 if (skb->skb_iif) {
5766                         secmark_perm = PACKET__FORWARD_OUT;
5767                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5768                                 return NF_DROP;
5769                 } else {
5770                         secmark_perm = PACKET__SEND;
5771                         peer_sid = SECINITSID_KERNEL;
5772                 }
5773         } else if (sk_listener(sk)) {
5774                 /* Locally generated packet but the associated socket is in the
5775                  * listening state which means this is a SYN-ACK packet.  In
5776                  * this particular case the correct security label is assigned
5777                  * to the connection/request_sock but unfortunately we can't
5778                  * query the request_sock as it isn't queued on the parent
5779                  * socket until after the SYN-ACK packet is sent; the only
5780                  * viable choice is to regenerate the label like we do in
5781                  * selinux_inet_conn_request().  See also selinux_ip_output()
5782                  * for similar problems. */
5783                 u32 skb_sid;
5784                 struct sk_security_struct *sksec;
5785
5786                 sksec = sk->sk_security;
5787                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5788                         return NF_DROP;
5789                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5790                  * and the packet has been through at least one XFRM
5791                  * transformation then we must be dealing with the "final"
5792                  * form of labeled IPsec packet; since we've already applied
5793                  * all of our access controls on this packet we can safely
5794                  * pass the packet. */
5795                 if (skb_sid == SECSID_NULL) {
5796                         switch (family) {
5797                         case PF_INET:
5798                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5799                                         return NF_ACCEPT;
5800                                 break;
5801                         case PF_INET6:
5802                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5803                                         return NF_ACCEPT;
5804                                 break;
5805                         default:
5806                                 return NF_DROP_ERR(-ECONNREFUSED);
5807                         }
5808                 }
5809                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5810                         return NF_DROP;
5811                 secmark_perm = PACKET__SEND;
5812         } else {
5813                 /* Locally generated packet, fetch the security label from the
5814                  * associated socket. */
5815                 struct sk_security_struct *sksec = sk->sk_security;
5816                 peer_sid = sksec->sid;
5817                 secmark_perm = PACKET__SEND;
5818         }
5819
5820         ad.type = LSM_AUDIT_DATA_NET;
5821         ad.u.net = &net;
5822         ad.u.net->netif = ifindex;
5823         ad.u.net->family = family;
5824         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5825                 return NF_DROP;
5826
5827         if (secmark_active)
5828                 if (avc_has_perm(&selinux_state,
5829                                  peer_sid, skb->secmark,
5830                                  SECCLASS_PACKET, secmark_perm, &ad))
5831                         return NF_DROP_ERR(-ECONNREFUSED);
5832
5833         if (peerlbl_active) {
5834                 u32 if_sid;
5835                 u32 node_sid;
5836
5837                 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5838                         return NF_DROP;
5839                 if (avc_has_perm(&selinux_state,
5840                                  peer_sid, if_sid,
5841                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5842                         return NF_DROP_ERR(-ECONNREFUSED);
5843
5844                 if (sel_netnode_sid(addrp, family, &node_sid))
5845                         return NF_DROP;
5846                 if (avc_has_perm(&selinux_state,
5847                                  peer_sid, node_sid,
5848                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5849                         return NF_DROP_ERR(-ECONNREFUSED);
5850         }
5851
5852         return NF_ACCEPT;
5853 }
5854
5855 static unsigned int selinux_ipv4_postroute(void *priv,
5856                                            struct sk_buff *skb,
5857                                            const struct nf_hook_state *state)
5858 {
5859         return selinux_ip_postroute(skb, state->out, PF_INET);
5860 }
5861
5862 #if IS_ENABLED(CONFIG_IPV6)
5863 static unsigned int selinux_ipv6_postroute(void *priv,
5864                                            struct sk_buff *skb,
5865                                            const struct nf_hook_state *state)
5866 {
5867         return selinux_ip_postroute(skb, state->out, PF_INET6);
5868 }
5869 #endif  /* IPV6 */
5870
5871 #endif  /* CONFIG_NETFILTER */
5872
5873 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5874 {
5875         return selinux_nlmsg_perm(sk, skb);
5876 }
5877
5878 static int ipc_alloc_security(struct kern_ipc_perm *perm,
5879                               u16 sclass)
5880 {
5881         struct ipc_security_struct *isec;
5882
5883         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5884         if (!isec)
5885                 return -ENOMEM;
5886
5887         isec->sclass = sclass;
5888         isec->sid = current_sid();
5889         perm->security = isec;
5890
5891         return 0;
5892 }
5893
5894 static void ipc_free_security(struct kern_ipc_perm *perm)
5895 {
5896         struct ipc_security_struct *isec = perm->security;
5897         perm->security = NULL;
5898         kfree(isec);
5899 }
5900
5901 static int msg_msg_alloc_security(struct msg_msg *msg)
5902 {
5903         struct msg_security_struct *msec;
5904
5905         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5906         if (!msec)
5907                 return -ENOMEM;
5908
5909         msec->sid = SECINITSID_UNLABELED;
5910         msg->security = msec;
5911
5912         return 0;
5913 }
5914
5915 static void msg_msg_free_security(struct msg_msg *msg)
5916 {
5917         struct msg_security_struct *msec = msg->security;
5918
5919         msg->security = NULL;
5920         kfree(msec);
5921 }
5922
5923 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5924                         u32 perms)
5925 {
5926         struct ipc_security_struct *isec;
5927         struct common_audit_data ad;
5928         u32 sid = current_sid();
5929
5930         isec = ipc_perms->security;
5931
5932         ad.type = LSM_AUDIT_DATA_IPC;
5933         ad.u.ipc_id = ipc_perms->key;
5934
5935         return avc_has_perm(&selinux_state,
5936                             sid, isec->sid, isec->sclass, perms, &ad);
5937 }
5938
5939 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5940 {
5941         return msg_msg_alloc_security(msg);
5942 }
5943
5944 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5945 {
5946         msg_msg_free_security(msg);
5947 }
5948
5949 /* message queue security operations */
5950 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5951 {
5952         struct ipc_security_struct *isec;
5953         struct common_audit_data ad;
5954         u32 sid = current_sid();
5955         int rc;
5956
5957         rc = ipc_alloc_security(msq, SECCLASS_MSGQ);
5958         if (rc)
5959                 return rc;
5960
5961         isec = msq->security;
5962
5963         ad.type = LSM_AUDIT_DATA_IPC;
5964         ad.u.ipc_id = msq->key;
5965
5966         rc = avc_has_perm(&selinux_state,
5967                           sid, isec->sid, SECCLASS_MSGQ,
5968                           MSGQ__CREATE, &ad);
5969         if (rc) {
5970                 ipc_free_security(msq);
5971                 return rc;
5972         }
5973         return 0;
5974 }
5975
5976 static void selinux_msg_queue_free_security(struct kern_ipc_perm *msq)
5977 {
5978         ipc_free_security(msq);
5979 }
5980
5981 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5982 {
5983         struct ipc_security_struct *isec;
5984         struct common_audit_data ad;
5985         u32 sid = current_sid();
5986
5987         isec = msq->security;
5988
5989         ad.type = LSM_AUDIT_DATA_IPC;
5990         ad.u.ipc_id = msq->key;
5991
5992         return avc_has_perm(&selinux_state,
5993                             sid, isec->sid, SECCLASS_MSGQ,
5994                             MSGQ__ASSOCIATE, &ad);
5995 }
5996
5997 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5998 {
5999         int err;
6000         int perms;
6001
6002         switch (cmd) {
6003         case IPC_INFO:
6004         case MSG_INFO:
6005                 /* No specific object, just general system-wide information. */
6006                 return avc_has_perm(&selinux_state,
6007                                     current_sid(), SECINITSID_KERNEL,
6008                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6009         case IPC_STAT:
6010         case MSG_STAT:
6011         case MSG_STAT_ANY:
6012                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6013                 break;
6014         case IPC_SET:
6015                 perms = MSGQ__SETATTR;
6016                 break;
6017         case IPC_RMID:
6018                 perms = MSGQ__DESTROY;
6019                 break;
6020         default:
6021                 return 0;
6022         }
6023
6024         err = ipc_has_perm(msq, perms);
6025         return err;
6026 }
6027
6028 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6029 {
6030         struct ipc_security_struct *isec;
6031         struct msg_security_struct *msec;
6032         struct common_audit_data ad;
6033         u32 sid = current_sid();
6034         int rc;
6035
6036         isec = msq->security;
6037         msec = msg->security;
6038
6039         /*
6040          * First time through, need to assign label to the message
6041          */
6042         if (msec->sid == SECINITSID_UNLABELED) {
6043                 /*
6044                  * Compute new sid based on current process and
6045                  * message queue this message will be stored in
6046                  */
6047                 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6048                                              SECCLASS_MSG, NULL, &msec->sid);
6049                 if (rc)
6050                         return rc;
6051         }
6052
6053         ad.type = LSM_AUDIT_DATA_IPC;
6054         ad.u.ipc_id = msq->key;
6055
6056         /* Can this process write to the queue? */
6057         rc = avc_has_perm(&selinux_state,
6058                           sid, isec->sid, SECCLASS_MSGQ,
6059                           MSGQ__WRITE, &ad);
6060         if (!rc)
6061                 /* Can this process send the message */
6062                 rc = avc_has_perm(&selinux_state,
6063                                   sid, msec->sid, SECCLASS_MSG,
6064                                   MSG__SEND, &ad);
6065         if (!rc)
6066                 /* Can the message be put in the queue? */
6067                 rc = avc_has_perm(&selinux_state,
6068                                   msec->sid, isec->sid, SECCLASS_MSGQ,
6069                                   MSGQ__ENQUEUE, &ad);
6070
6071         return rc;
6072 }
6073
6074 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6075                                     struct task_struct *target,
6076                                     long type, int mode)
6077 {
6078         struct ipc_security_struct *isec;
6079         struct msg_security_struct *msec;
6080         struct common_audit_data ad;
6081         u32 sid = task_sid(target);
6082         int rc;
6083
6084         isec = msq->security;
6085         msec = msg->security;
6086
6087         ad.type = LSM_AUDIT_DATA_IPC;
6088         ad.u.ipc_id = msq->key;
6089
6090         rc = avc_has_perm(&selinux_state,
6091                           sid, isec->sid,
6092                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6093         if (!rc)
6094                 rc = avc_has_perm(&selinux_state,
6095                                   sid, msec->sid,
6096                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6097         return rc;
6098 }
6099
6100 /* Shared Memory security operations */
6101 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6102 {
6103         struct ipc_security_struct *isec;
6104         struct common_audit_data ad;
6105         u32 sid = current_sid();
6106         int rc;
6107
6108         rc = ipc_alloc_security(shp, SECCLASS_SHM);
6109         if (rc)
6110                 return rc;
6111
6112         isec = shp->security;
6113
6114         ad.type = LSM_AUDIT_DATA_IPC;
6115         ad.u.ipc_id = shp->key;
6116
6117         rc = avc_has_perm(&selinux_state,
6118                           sid, isec->sid, SECCLASS_SHM,
6119                           SHM__CREATE, &ad);
6120         if (rc) {
6121                 ipc_free_security(shp);
6122                 return rc;
6123         }
6124         return 0;
6125 }
6126
6127 static void selinux_shm_free_security(struct kern_ipc_perm *shp)
6128 {
6129         ipc_free_security(shp);
6130 }
6131
6132 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6133 {
6134         struct ipc_security_struct *isec;
6135         struct common_audit_data ad;
6136         u32 sid = current_sid();
6137
6138         isec = shp->security;
6139
6140         ad.type = LSM_AUDIT_DATA_IPC;
6141         ad.u.ipc_id = shp->key;
6142
6143         return avc_has_perm(&selinux_state,
6144                             sid, isec->sid, SECCLASS_SHM,
6145                             SHM__ASSOCIATE, &ad);
6146 }
6147
6148 /* Note, at this point, shp is locked down */
6149 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6150 {
6151         int perms;
6152         int err;
6153
6154         switch (cmd) {
6155         case IPC_INFO:
6156         case SHM_INFO:
6157                 /* No specific object, just general system-wide information. */
6158                 return avc_has_perm(&selinux_state,
6159                                     current_sid(), SECINITSID_KERNEL,
6160                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6161         case IPC_STAT:
6162         case SHM_STAT:
6163         case SHM_STAT_ANY:
6164                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6165                 break;
6166         case IPC_SET:
6167                 perms = SHM__SETATTR;
6168                 break;
6169         case SHM_LOCK:
6170         case SHM_UNLOCK:
6171                 perms = SHM__LOCK;
6172                 break;
6173         case IPC_RMID:
6174                 perms = SHM__DESTROY;
6175                 break;
6176         default:
6177                 return 0;
6178         }
6179
6180         err = ipc_has_perm(shp, perms);
6181         return err;
6182 }
6183
6184 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6185                              char __user *shmaddr, int shmflg)
6186 {
6187         u32 perms;
6188
6189         if (shmflg & SHM_RDONLY)
6190                 perms = SHM__READ;
6191         else
6192                 perms = SHM__READ | SHM__WRITE;
6193
6194         return ipc_has_perm(shp, perms);
6195 }
6196
6197 /* Semaphore security operations */
6198 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6199 {
6200         struct ipc_security_struct *isec;
6201         struct common_audit_data ad;
6202         u32 sid = current_sid();
6203         int rc;
6204
6205         rc = ipc_alloc_security(sma, SECCLASS_SEM);
6206         if (rc)
6207                 return rc;
6208
6209         isec = sma->security;
6210
6211         ad.type = LSM_AUDIT_DATA_IPC;
6212         ad.u.ipc_id = sma->key;
6213
6214         rc = avc_has_perm(&selinux_state,
6215                           sid, isec->sid, SECCLASS_SEM,
6216                           SEM__CREATE, &ad);
6217         if (rc) {
6218                 ipc_free_security(sma);
6219                 return rc;
6220         }
6221         return 0;
6222 }
6223
6224 static void selinux_sem_free_security(struct kern_ipc_perm *sma)
6225 {
6226         ipc_free_security(sma);
6227 }
6228
6229 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6230 {
6231         struct ipc_security_struct *isec;
6232         struct common_audit_data ad;
6233         u32 sid = current_sid();
6234
6235         isec = sma->security;
6236
6237         ad.type = LSM_AUDIT_DATA_IPC;
6238         ad.u.ipc_id = sma->key;
6239
6240         return avc_has_perm(&selinux_state,
6241                             sid, isec->sid, SECCLASS_SEM,
6242                             SEM__ASSOCIATE, &ad);
6243 }
6244
6245 /* Note, at this point, sma is locked down */
6246 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6247 {
6248         int err;
6249         u32 perms;
6250
6251         switch (cmd) {
6252         case IPC_INFO:
6253         case SEM_INFO:
6254                 /* No specific object, just general system-wide information. */
6255                 return avc_has_perm(&selinux_state,
6256                                     current_sid(), SECINITSID_KERNEL,
6257                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6258         case GETPID:
6259         case GETNCNT:
6260         case GETZCNT:
6261                 perms = SEM__GETATTR;
6262                 break;
6263         case GETVAL:
6264         case GETALL:
6265                 perms = SEM__READ;
6266                 break;
6267         case SETVAL:
6268         case SETALL:
6269                 perms = SEM__WRITE;
6270                 break;
6271         case IPC_RMID:
6272                 perms = SEM__DESTROY;
6273                 break;
6274         case IPC_SET:
6275                 perms = SEM__SETATTR;
6276                 break;
6277         case IPC_STAT:
6278         case SEM_STAT:
6279         case SEM_STAT_ANY:
6280                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6281                 break;
6282         default:
6283                 return 0;
6284         }
6285
6286         err = ipc_has_perm(sma, perms);
6287         return err;
6288 }
6289
6290 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6291                              struct sembuf *sops, unsigned nsops, int alter)
6292 {
6293         u32 perms;
6294
6295         if (alter)
6296                 perms = SEM__READ | SEM__WRITE;
6297         else
6298                 perms = SEM__READ;
6299
6300         return ipc_has_perm(sma, perms);
6301 }
6302
6303 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6304 {
6305         u32 av = 0;
6306
6307         av = 0;
6308         if (flag & S_IRUGO)
6309                 av |= IPC__UNIX_READ;
6310         if (flag & S_IWUGO)
6311                 av |= IPC__UNIX_WRITE;
6312
6313         if (av == 0)
6314                 return 0;
6315
6316         return ipc_has_perm(ipcp, av);
6317 }
6318
6319 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6320 {
6321         struct ipc_security_struct *isec = ipcp->security;
6322         *secid = isec->sid;
6323 }
6324
6325 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6326 {
6327         if (inode)
6328                 inode_doinit_with_dentry(inode, dentry);
6329 }
6330
6331 static int selinux_getprocattr(struct task_struct *p,
6332                                char *name, char **value)
6333 {
6334         const struct task_security_struct *__tsec;
6335         u32 sid;
6336         int error;
6337         unsigned len;
6338
6339         rcu_read_lock();
6340         __tsec = __task_cred(p)->security;
6341
6342         if (current != p) {
6343                 error = avc_has_perm(&selinux_state,
6344                                      current_sid(), __tsec->sid,
6345                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6346                 if (error)
6347                         goto bad;
6348         }
6349
6350         if (!strcmp(name, "current"))
6351                 sid = __tsec->sid;
6352         else if (!strcmp(name, "prev"))
6353                 sid = __tsec->osid;
6354         else if (!strcmp(name, "exec"))
6355                 sid = __tsec->exec_sid;
6356         else if (!strcmp(name, "fscreate"))
6357                 sid = __tsec->create_sid;
6358         else if (!strcmp(name, "keycreate"))
6359                 sid = __tsec->keycreate_sid;
6360         else if (!strcmp(name, "sockcreate"))
6361                 sid = __tsec->sockcreate_sid;
6362         else {
6363                 error = -EINVAL;
6364                 goto bad;
6365         }
6366         rcu_read_unlock();
6367
6368         if (!sid)
6369                 return 0;
6370
6371         error = security_sid_to_context(&selinux_state, sid, value, &len);
6372         if (error)
6373                 return error;
6374         return len;
6375
6376 bad:
6377         rcu_read_unlock();
6378         return error;
6379 }
6380
6381 static int selinux_setprocattr(const char *name, void *value, size_t size)
6382 {
6383         struct task_security_struct *tsec;
6384         struct cred *new;
6385         u32 mysid = current_sid(), sid = 0, ptsid;
6386         int error;
6387         char *str = value;
6388
6389         /*
6390          * Basic control over ability to set these attributes at all.
6391          */
6392         if (!strcmp(name, "exec"))
6393                 error = avc_has_perm(&selinux_state,
6394                                      mysid, mysid, SECCLASS_PROCESS,
6395                                      PROCESS__SETEXEC, NULL);
6396         else if (!strcmp(name, "fscreate"))
6397                 error = avc_has_perm(&selinux_state,
6398                                      mysid, mysid, SECCLASS_PROCESS,
6399                                      PROCESS__SETFSCREATE, NULL);
6400         else if (!strcmp(name, "keycreate"))
6401                 error = avc_has_perm(&selinux_state,
6402                                      mysid, mysid, SECCLASS_PROCESS,
6403                                      PROCESS__SETKEYCREATE, NULL);
6404         else if (!strcmp(name, "sockcreate"))
6405                 error = avc_has_perm(&selinux_state,
6406                                      mysid, mysid, SECCLASS_PROCESS,
6407                                      PROCESS__SETSOCKCREATE, NULL);
6408         else if (!strcmp(name, "current"))
6409                 error = avc_has_perm(&selinux_state,
6410                                      mysid, mysid, SECCLASS_PROCESS,
6411                                      PROCESS__SETCURRENT, NULL);
6412         else
6413                 error = -EINVAL;
6414         if (error)
6415                 return error;
6416
6417         /* Obtain a SID for the context, if one was specified. */
6418         if (size && str[0] && str[0] != '\n') {
6419                 if (str[size-1] == '\n') {
6420                         str[size-1] = 0;
6421                         size--;
6422                 }
6423                 error = security_context_to_sid(&selinux_state, value, size,
6424                                                 &sid, GFP_KERNEL);
6425                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6426                         if (!has_cap_mac_admin(true)) {
6427                                 struct audit_buffer *ab;
6428                                 size_t audit_size;
6429
6430                                 /* We strip a nul only if it is at the end, otherwise the
6431                                  * context contains a nul and we should audit that */
6432                                 if (str[size - 1] == '\0')
6433                                         audit_size = size - 1;
6434                                 else
6435                                         audit_size = size;
6436                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
6437                                 audit_log_format(ab, "op=fscreate invalid_context=");
6438                                 audit_log_n_untrustedstring(ab, value, audit_size);
6439                                 audit_log_end(ab);
6440
6441                                 return error;
6442                         }
6443                         error = security_context_to_sid_force(
6444                                                       &selinux_state,
6445                                                       value, size, &sid);
6446                 }
6447                 if (error)
6448                         return error;
6449         }
6450
6451         new = prepare_creds();
6452         if (!new)
6453                 return -ENOMEM;
6454
6455         /* Permission checking based on the specified context is
6456            performed during the actual operation (execve,
6457            open/mkdir/...), when we know the full context of the
6458            operation.  See selinux_bprm_set_creds for the execve
6459            checks and may_create for the file creation checks. The
6460            operation will then fail if the context is not permitted. */
6461         tsec = new->security;
6462         if (!strcmp(name, "exec")) {
6463                 tsec->exec_sid = sid;
6464         } else if (!strcmp(name, "fscreate")) {
6465                 tsec->create_sid = sid;
6466         } else if (!strcmp(name, "keycreate")) {
6467                 error = avc_has_perm(&selinux_state,
6468                                      mysid, sid, SECCLASS_KEY, KEY__CREATE,
6469                                      NULL);
6470                 if (error)
6471                         goto abort_change;
6472                 tsec->keycreate_sid = sid;
6473         } else if (!strcmp(name, "sockcreate")) {
6474                 tsec->sockcreate_sid = sid;
6475         } else if (!strcmp(name, "current")) {
6476                 error = -EINVAL;
6477                 if (sid == 0)
6478                         goto abort_change;
6479
6480                 /* Only allow single threaded processes to change context */
6481                 error = -EPERM;
6482                 if (!current_is_single_threaded()) {
6483                         error = security_bounded_transition(&selinux_state,
6484                                                             tsec->sid, sid);
6485                         if (error)
6486                                 goto abort_change;
6487                 }
6488
6489                 /* Check permissions for the transition. */
6490                 error = avc_has_perm(&selinux_state,
6491                                      tsec->sid, sid, SECCLASS_PROCESS,
6492                                      PROCESS__DYNTRANSITION, NULL);
6493                 if (error)
6494                         goto abort_change;
6495
6496                 /* Check for ptracing, and update the task SID if ok.
6497                    Otherwise, leave SID unchanged and fail. */
6498                 ptsid = ptrace_parent_sid();
6499                 if (ptsid != 0) {
6500                         error = avc_has_perm(&selinux_state,
6501                                              ptsid, sid, SECCLASS_PROCESS,
6502                                              PROCESS__PTRACE, NULL);
6503                         if (error)
6504                                 goto abort_change;
6505                 }
6506
6507                 tsec->sid = sid;
6508         } else {
6509                 error = -EINVAL;
6510                 goto abort_change;
6511         }
6512
6513         commit_creds(new);
6514         return size;
6515
6516 abort_change:
6517         abort_creds(new);
6518         return error;
6519 }
6520
6521 static int selinux_ismaclabel(const char *name)
6522 {
6523         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6524 }
6525
6526 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6527 {
6528         return security_sid_to_context(&selinux_state, secid,
6529                                        secdata, seclen);
6530 }
6531
6532 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6533 {
6534         return security_context_to_sid(&selinux_state, secdata, seclen,
6535                                        secid, GFP_KERNEL);
6536 }
6537
6538 static void selinux_release_secctx(char *secdata, u32 seclen)
6539 {
6540         kfree(secdata);
6541 }
6542
6543 static void selinux_inode_invalidate_secctx(struct inode *inode)
6544 {
6545         struct inode_security_struct *isec = inode->i_security;
6546
6547         spin_lock(&isec->lock);
6548         isec->initialized = LABEL_INVALID;
6549         spin_unlock(&isec->lock);
6550 }
6551
6552 /*
6553  *      called with inode->i_mutex locked
6554  */
6555 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6556 {
6557         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6558 }
6559
6560 /*
6561  *      called with inode->i_mutex locked
6562  */
6563 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6564 {
6565         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6566 }
6567
6568 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6569 {
6570         int len = 0;
6571         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6572                                                 ctx, true);
6573         if (len < 0)
6574                 return len;
6575         *ctxlen = len;
6576         return 0;
6577 }
6578 #ifdef CONFIG_KEYS
6579
6580 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6581                              unsigned long flags)
6582 {
6583         const struct task_security_struct *tsec;
6584         struct key_security_struct *ksec;
6585
6586         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6587         if (!ksec)
6588                 return -ENOMEM;
6589
6590         tsec = cred->security;
6591         if (tsec->keycreate_sid)
6592                 ksec->sid = tsec->keycreate_sid;
6593         else
6594                 ksec->sid = tsec->sid;
6595
6596         k->security = ksec;
6597         return 0;
6598 }
6599
6600 static void selinux_key_free(struct key *k)
6601 {
6602         struct key_security_struct *ksec = k->security;
6603
6604         k->security = NULL;
6605         kfree(ksec);
6606 }
6607
6608 static int selinux_key_permission(key_ref_t key_ref,
6609                                   const struct cred *cred,
6610                                   unsigned perm)
6611 {
6612         struct key *key;
6613         struct key_security_struct *ksec;
6614         u32 sid;
6615
6616         /* if no specific permissions are requested, we skip the
6617            permission check. No serious, additional covert channels
6618            appear to be created. */
6619         if (perm == 0)
6620                 return 0;
6621
6622         sid = cred_sid(cred);
6623
6624         key = key_ref_to_ptr(key_ref);
6625         ksec = key->security;
6626
6627         return avc_has_perm(&selinux_state,
6628                             sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6629 }
6630
6631 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6632 {
6633         struct key_security_struct *ksec = key->security;
6634         char *context = NULL;
6635         unsigned len;
6636         int rc;
6637
6638         rc = security_sid_to_context(&selinux_state, ksec->sid,
6639                                      &context, &len);
6640         if (!rc)
6641                 rc = len;
6642         *_buffer = context;
6643         return rc;
6644 }
6645 #endif
6646
6647 #ifdef CONFIG_SECURITY_INFINIBAND
6648 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6649 {
6650         struct common_audit_data ad;
6651         int err;
6652         u32 sid = 0;
6653         struct ib_security_struct *sec = ib_sec;
6654         struct lsm_ibpkey_audit ibpkey;
6655
6656         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6657         if (err)
6658                 return err;
6659
6660         ad.type = LSM_AUDIT_DATA_IBPKEY;
6661         ibpkey.subnet_prefix = subnet_prefix;
6662         ibpkey.pkey = pkey_val;
6663         ad.u.ibpkey = &ibpkey;
6664         return avc_has_perm(&selinux_state,
6665                             sec->sid, sid,
6666                             SECCLASS_INFINIBAND_PKEY,
6667                             INFINIBAND_PKEY__ACCESS, &ad);
6668 }
6669
6670 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6671                                             u8 port_num)
6672 {
6673         struct common_audit_data ad;
6674         int err;
6675         u32 sid = 0;
6676         struct ib_security_struct *sec = ib_sec;
6677         struct lsm_ibendport_audit ibendport;
6678
6679         err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6680                                       &sid);
6681
6682         if (err)
6683                 return err;
6684
6685         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6686         strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6687         ibendport.port = port_num;
6688         ad.u.ibendport = &ibendport;
6689         return avc_has_perm(&selinux_state,
6690                             sec->sid, sid,
6691                             SECCLASS_INFINIBAND_ENDPORT,
6692                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6693 }
6694
6695 static int selinux_ib_alloc_security(void **ib_sec)
6696 {
6697         struct ib_security_struct *sec;
6698
6699         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6700         if (!sec)
6701                 return -ENOMEM;
6702         sec->sid = current_sid();
6703
6704         *ib_sec = sec;
6705         return 0;
6706 }
6707
6708 static void selinux_ib_free_security(void *ib_sec)
6709 {
6710         kfree(ib_sec);
6711 }
6712 #endif
6713
6714 #ifdef CONFIG_BPF_SYSCALL
6715 static int selinux_bpf(int cmd, union bpf_attr *attr,
6716                                      unsigned int size)
6717 {
6718         u32 sid = current_sid();
6719         int ret;
6720
6721         switch (cmd) {
6722         case BPF_MAP_CREATE:
6723                 ret = avc_has_perm(&selinux_state,
6724                                    sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6725                                    NULL);
6726                 break;
6727         case BPF_PROG_LOAD:
6728                 ret = avc_has_perm(&selinux_state,
6729                                    sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6730                                    NULL);
6731                 break;
6732         default:
6733                 ret = 0;
6734                 break;
6735         }
6736
6737         return ret;
6738 }
6739
6740 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6741 {
6742         u32 av = 0;
6743
6744         if (fmode & FMODE_READ)
6745                 av |= BPF__MAP_READ;
6746         if (fmode & FMODE_WRITE)
6747                 av |= BPF__MAP_WRITE;
6748         return av;
6749 }
6750
6751 /* This function will check the file pass through unix socket or binder to see
6752  * if it is a bpf related object. And apply correspinding checks on the bpf
6753  * object based on the type. The bpf maps and programs, not like other files and
6754  * socket, are using a shared anonymous inode inside the kernel as their inode.
6755  * So checking that inode cannot identify if the process have privilege to
6756  * access the bpf object and that's why we have to add this additional check in
6757  * selinux_file_receive and selinux_binder_transfer_files.
6758  */
6759 static int bpf_fd_pass(struct file *file, u32 sid)
6760 {
6761         struct bpf_security_struct *bpfsec;
6762         struct bpf_prog *prog;
6763         struct bpf_map *map;
6764         int ret;
6765
6766         if (file->f_op == &bpf_map_fops) {
6767                 map = file->private_data;
6768                 bpfsec = map->security;
6769                 ret = avc_has_perm(&selinux_state,
6770                                    sid, bpfsec->sid, SECCLASS_BPF,
6771                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6772                 if (ret)
6773                         return ret;
6774         } else if (file->f_op == &bpf_prog_fops) {
6775                 prog = file->private_data;
6776                 bpfsec = prog->aux->security;
6777                 ret = avc_has_perm(&selinux_state,
6778                                    sid, bpfsec->sid, SECCLASS_BPF,
6779                                    BPF__PROG_RUN, NULL);
6780                 if (ret)
6781                         return ret;
6782         }
6783         return 0;
6784 }
6785
6786 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6787 {
6788         u32 sid = current_sid();
6789         struct bpf_security_struct *bpfsec;
6790
6791         bpfsec = map->security;
6792         return avc_has_perm(&selinux_state,
6793                             sid, bpfsec->sid, SECCLASS_BPF,
6794                             bpf_map_fmode_to_av(fmode), NULL);
6795 }
6796
6797 static int selinux_bpf_prog(struct bpf_prog *prog)
6798 {
6799         u32 sid = current_sid();
6800         struct bpf_security_struct *bpfsec;
6801
6802         bpfsec = prog->aux->security;
6803         return avc_has_perm(&selinux_state,
6804                             sid, bpfsec->sid, SECCLASS_BPF,
6805                             BPF__PROG_RUN, NULL);
6806 }
6807
6808 static int selinux_bpf_map_alloc(struct bpf_map *map)
6809 {
6810         struct bpf_security_struct *bpfsec;
6811
6812         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6813         if (!bpfsec)
6814                 return -ENOMEM;
6815
6816         bpfsec->sid = current_sid();
6817         map->security = bpfsec;
6818
6819         return 0;
6820 }
6821
6822 static void selinux_bpf_map_free(struct bpf_map *map)
6823 {
6824         struct bpf_security_struct *bpfsec = map->security;
6825
6826         map->security = NULL;
6827         kfree(bpfsec);
6828 }
6829
6830 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6831 {
6832         struct bpf_security_struct *bpfsec;
6833
6834         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6835         if (!bpfsec)
6836                 return -ENOMEM;
6837
6838         bpfsec->sid = current_sid();
6839         aux->security = bpfsec;
6840
6841         return 0;
6842 }
6843
6844 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6845 {
6846         struct bpf_security_struct *bpfsec = aux->security;
6847
6848         aux->security = NULL;
6849         kfree(bpfsec);
6850 }
6851 #endif
6852
6853 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6854         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6855         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6856         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6857         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6858
6859         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6860         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6861         LSM_HOOK_INIT(capget, selinux_capget),
6862         LSM_HOOK_INIT(capset, selinux_capset),
6863         LSM_HOOK_INIT(capable, selinux_capable),
6864         LSM_HOOK_INIT(quotactl, selinux_quotactl),
6865         LSM_HOOK_INIT(quota_on, selinux_quota_on),
6866         LSM_HOOK_INIT(syslog, selinux_syslog),
6867         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6868
6869         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6870
6871         LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6872         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6873         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6874
6875         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6876         LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6877         LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
6878         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6879         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6880         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6881         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6882         LSM_HOOK_INIT(sb_mount, selinux_mount),
6883         LSM_HOOK_INIT(sb_umount, selinux_umount),
6884         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6885         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6886         LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
6887
6888         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6889         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6890
6891         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6892         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6893         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6894         LSM_HOOK_INIT(inode_create, selinux_inode_create),
6895         LSM_HOOK_INIT(inode_link, selinux_inode_link),
6896         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6897         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6898         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6899         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6900         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6901         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6902         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6903         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6904         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6905         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6906         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6907         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6908         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6909         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6910         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6911         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6912         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6913         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6914         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6915         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6916         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6917         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6918
6919         LSM_HOOK_INIT(file_permission, selinux_file_permission),
6920         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6921         LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6922         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6923         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6924         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6925         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6926         LSM_HOOK_INIT(file_lock, selinux_file_lock),
6927         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6928         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6929         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6930         LSM_HOOK_INIT(file_receive, selinux_file_receive),
6931
6932         LSM_HOOK_INIT(file_open, selinux_file_open),
6933
6934         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6935         LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6936         LSM_HOOK_INIT(cred_free, selinux_cred_free),
6937         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6938         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6939         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
6940         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6941         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6942         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6943         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6944         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6945         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6946         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6947         LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6948         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6949         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6950         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6951         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6952         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6953         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6954         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6955         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6956         LSM_HOOK_INIT(task_kill, selinux_task_kill),
6957         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6958
6959         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6960         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6961
6962         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6963         LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6964
6965         LSM_HOOK_INIT(msg_queue_alloc_security,
6966                         selinux_msg_queue_alloc_security),
6967         LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6968         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6969         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6970         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6971         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6972
6973         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6974         LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6975         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6976         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6977         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6978
6979         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6980         LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6981         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6982         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6983         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6984
6985         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6986
6987         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6988         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6989
6990         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6991         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6992         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6993         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6994         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6995         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6996         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6997         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6998
6999         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7000         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7001
7002         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7003         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7004         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7005         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7006         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7007         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7008         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7009         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7010         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7011         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7012         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7013         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7014         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7015         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7016         LSM_HOOK_INIT(socket_getpeersec_stream,
7017                         selinux_socket_getpeersec_stream),
7018         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7019         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7020         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7021         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7022         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7023         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7024         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7025         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7026         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7027         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7028         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7029         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7030         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7031         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7032         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7033         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7034         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7035         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7036         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7037         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7038         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7039         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7040 #ifdef CONFIG_SECURITY_INFINIBAND
7041         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7042         LSM_HOOK_INIT(ib_endport_manage_subnet,
7043                       selinux_ib_endport_manage_subnet),
7044         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7045         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7046 #endif
7047 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7048         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7049         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7050         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7051         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7052         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7053         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7054                         selinux_xfrm_state_alloc_acquire),
7055         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7056         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7057         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7058         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7059                         selinux_xfrm_state_pol_flow_match),
7060         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7061 #endif
7062
7063 #ifdef CONFIG_KEYS
7064         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7065         LSM_HOOK_INIT(key_free, selinux_key_free),
7066         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7067         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7068 #endif
7069
7070 #ifdef CONFIG_AUDIT
7071         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7072         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7073         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7074         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7075 #endif
7076
7077 #ifdef CONFIG_BPF_SYSCALL
7078         LSM_HOOK_INIT(bpf, selinux_bpf),
7079         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7080         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7081         LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7082         LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7083         LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7084         LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7085 #endif
7086 };
7087
7088 static __init int selinux_init(void)
7089 {
7090         if (!security_module_enable("selinux")) {
7091                 selinux_enabled = 0;
7092                 return 0;
7093         }
7094
7095         if (!selinux_enabled) {
7096                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
7097                 return 0;
7098         }
7099
7100         printk(KERN_INFO "SELinux:  Initializing.\n");
7101
7102         memset(&selinux_state, 0, sizeof(selinux_state));
7103         enforcing_set(&selinux_state, selinux_enforcing_boot);
7104         selinux_state.checkreqprot = selinux_checkreqprot_boot;
7105         selinux_ss_init(&selinux_state.ss);
7106         selinux_avc_init(&selinux_state.avc);
7107
7108         /* Set the security state for the initial task. */
7109         cred_init_security();
7110
7111         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7112
7113         sel_inode_cache = kmem_cache_create("selinux_inode_security",
7114                                             sizeof(struct inode_security_struct),
7115                                             0, SLAB_PANIC, NULL);
7116         file_security_cache = kmem_cache_create("selinux_file_security",
7117                                             sizeof(struct file_security_struct),
7118                                             0, SLAB_PANIC, NULL);
7119         avc_init();
7120
7121         avtab_cache_init();
7122
7123         ebitmap_cache_init();
7124
7125         hashtab_cache_init();
7126
7127         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7128
7129         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7130                 panic("SELinux: Unable to register AVC netcache callback\n");
7131
7132         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7133                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7134
7135         if (selinux_enforcing_boot)
7136                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
7137         else
7138                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
7139
7140         return 0;
7141 }
7142
7143 static void delayed_superblock_init(struct super_block *sb, void *unused)
7144 {
7145         superblock_doinit(sb, NULL);
7146 }
7147
7148 void selinux_complete_init(void)
7149 {
7150         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
7151
7152         /* Set up any superblocks initialized prior to the policy load. */
7153         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
7154         iterate_supers(delayed_superblock_init, NULL);
7155 }
7156
7157 /* SELinux requires early initialization in order to label
7158    all processes and objects when they are created. */
7159 security_initcall(selinux_init);
7160
7161 #if defined(CONFIG_NETFILTER)
7162
7163 static const struct nf_hook_ops selinux_nf_ops[] = {
7164         {
7165                 .hook =         selinux_ipv4_postroute,
7166                 .pf =           NFPROTO_IPV4,
7167                 .hooknum =      NF_INET_POST_ROUTING,
7168                 .priority =     NF_IP_PRI_SELINUX_LAST,
7169         },
7170         {
7171                 .hook =         selinux_ipv4_forward,
7172                 .pf =           NFPROTO_IPV4,
7173                 .hooknum =      NF_INET_FORWARD,
7174                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7175         },
7176         {
7177                 .hook =         selinux_ipv4_output,
7178                 .pf =           NFPROTO_IPV4,
7179                 .hooknum =      NF_INET_LOCAL_OUT,
7180                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7181         },
7182 #if IS_ENABLED(CONFIG_IPV6)
7183         {
7184                 .hook =         selinux_ipv6_postroute,
7185                 .pf =           NFPROTO_IPV6,
7186                 .hooknum =      NF_INET_POST_ROUTING,
7187                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7188         },
7189         {
7190                 .hook =         selinux_ipv6_forward,
7191                 .pf =           NFPROTO_IPV6,
7192                 .hooknum =      NF_INET_FORWARD,
7193                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7194         },
7195         {
7196                 .hook =         selinux_ipv6_output,
7197                 .pf =           NFPROTO_IPV6,
7198                 .hooknum =      NF_INET_LOCAL_OUT,
7199                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7200         },
7201 #endif  /* IPV6 */
7202 };
7203
7204 static int __net_init selinux_nf_register(struct net *net)
7205 {
7206         return nf_register_net_hooks(net, selinux_nf_ops,
7207                                      ARRAY_SIZE(selinux_nf_ops));
7208 }
7209
7210 static void __net_exit selinux_nf_unregister(struct net *net)
7211 {
7212         nf_unregister_net_hooks(net, selinux_nf_ops,
7213                                 ARRAY_SIZE(selinux_nf_ops));
7214 }
7215
7216 static struct pernet_operations selinux_net_ops = {
7217         .init = selinux_nf_register,
7218         .exit = selinux_nf_unregister,
7219 };
7220
7221 static int __init selinux_nf_ip_init(void)
7222 {
7223         int err;
7224
7225         if (!selinux_enabled)
7226                 return 0;
7227
7228         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
7229
7230         err = register_pernet_subsys(&selinux_net_ops);
7231         if (err)
7232                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7233
7234         return 0;
7235 }
7236 __initcall(selinux_nf_ip_init);
7237
7238 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7239 static void selinux_nf_ip_exit(void)
7240 {
7241         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
7242
7243         unregister_pernet_subsys(&selinux_net_ops);
7244 }
7245 #endif
7246
7247 #else /* CONFIG_NETFILTER */
7248
7249 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7250 #define selinux_nf_ip_exit()
7251 #endif
7252
7253 #endif /* CONFIG_NETFILTER */
7254
7255 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7256 int selinux_disable(struct selinux_state *state)
7257 {
7258         if (state->initialized) {
7259                 /* Not permitted after initial policy load. */
7260                 return -EINVAL;
7261         }
7262
7263         if (state->disabled) {
7264                 /* Only do this once. */
7265                 return -EINVAL;
7266         }
7267
7268         state->disabled = 1;
7269
7270         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
7271
7272         selinux_enabled = 0;
7273
7274         security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7275
7276         /* Try to destroy the avc node cache */
7277         avc_disable();
7278
7279         /* Unregister netfilter hooks. */
7280         selinux_nf_ip_exit();
7281
7282         /* Unregister selinuxfs. */
7283         exit_sel_fs();
7284
7285         return 0;
7286 }
7287 #endif