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 @dentry parameter should be set to a dentry of the inode.
 278  */
 279 static int __inode_security_revalidate(struct inode *inode,
 280                                        struct dentry *dentry,
 281                                        bool may_sleep)
 282 {
 283         struct inode_security_struct *isec = inode->i_security;
 284
 285         might_sleep_if(may_sleep);
 286
 287         if (selinux_state.initialized &&
 288             isec->initialized != LABEL_INITIALIZED) {
 289                 if (!may_sleep)
 290                         return -ECHILD;
 291
 292                 /*
 293                  * Try reloading the inode security label.  This will fail if
 294                  * @opt_dentry is NULL and no dentry for this inode can be
 295                  * found; in that case, continue using the old label.
 296                  */
 297                 inode_doinit_with_dentry(inode, dentry);
 298         }
 299         return 0;
 300 }
 301
 302 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 303 {
 304         return inode->i_security;
 305 }
 306
 307 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 308 {
 309         int error;
 310
 311         error = __inode_security_revalidate(inode, NULL, !rcu);
 312         if (error)
 313                 return ERR_PTR(error);
 314         return inode->i_security;
 315 }
 316
 317 /*
 318  * Get the security label of an inode.
 319  */
 320 static struct inode_security_struct *inode_security(struct inode *inode)
 321 {
 322         __inode_security_revalidate(inode, NULL, true);
 323         return inode->i_security;
 324 }
 325
 326 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 327 {
 328         struct inode *inode = d_backing_inode(dentry);
 329
 330         return inode->i_security;
 331 }
 332
 333 /*
 334  * Get the security label of a dentry's backing inode.
 335  */
 336 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 337 {
 338         struct inode *inode = d_backing_inode(dentry);
 339
 340         __inode_security_revalidate(inode, dentry, true);
 341         return inode->i_security;
 342 }
 343
 344 static void inode_free_rcu(struct rcu_head *head)
 345 {
 346         struct inode_security_struct *isec;
 347
 348         isec = container_of(head, struct inode_security_struct, rcu);
 349         kmem_cache_free(sel_inode_cache, isec);
 350 }
 351
 352 static void inode_free_security(struct inode *inode)
 353 {
 354         struct inode_security_struct *isec = inode->i_security;
 355         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 356
 357         /*
 358          * As not all inode security structures are in a list, we check for
 359          * empty list outside of the lock to make sure that we won't waste
 360          * time taking a lock doing nothing.
 361          *
 362          * The list_del_init() function can be safely called more than once.
 363          * It should not be possible for this function to be called with
 364          * concurrent list_add(), but for better safety against future changes
 365          * in the code, we use list_empty_careful() here.
 366          */
 367         if (!list_empty_careful(&isec->list)) {
 368                 spin_lock(&sbsec->isec_lock);
 369                 list_del_init(&isec->list);
 370                 spin_unlock(&sbsec->isec_lock);
 371         }
 372
 373         /*
 374          * The inode may still be referenced in a path walk and
 375          * a call to selinux_inode_permission() can be made
 376          * after inode_free_security() is called. Ideally, the VFS
 377          * wouldn't do this, but fixing that is a much harder
 378          * job. For now, simply free the i_security via RCU, and
 379          * leave the current inode->i_security pointer intact.
 380          * The inode will be freed after the RCU grace period too.
 381          */
 382         call_rcu(&isec->rcu, inode_free_rcu);
 383 }
 384
 385 static int file_alloc_security(struct file *file)
 386 {
 387         struct file_security_struct *fsec;
 388         u32 sid = current_sid();
 389
 390         fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
 391         if (!fsec)
 392                 return -ENOMEM;
 393
 394         fsec->sid = sid;
 395         fsec->fown_sid = sid;
 396         file->f_security = fsec;
 397
 398         return 0;
 399 }
 400
 401 static void file_free_security(struct file *file)
 402 {
 403         struct file_security_struct *fsec = file->f_security;
 404         file->f_security = NULL;
 405         kmem_cache_free(file_security_cache, fsec);
 406 }
 407
 408 static int superblock_alloc_security(struct super_block *sb)
 409 {
 410         struct superblock_security_struct *sbsec;
 411
 412         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 413         if (!sbsec)
 414                 return -ENOMEM;
 415
 416         mutex_init(&sbsec->lock);
 417         INIT_LIST_HEAD(&sbsec->isec_head);
 418         spin_lock_init(&sbsec->isec_lock);
 419         sbsec->sb = sb;
 420         sbsec->sid = SECINITSID_UNLABELED;
 421         sbsec->def_sid = SECINITSID_FILE;
 422         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 423         sb->s_security = sbsec;
 424
 425         return 0;
 426 }
 427
 428 static void superblock_free_security(struct super_block *sb)
 429 {
 430         struct superblock_security_struct *sbsec = sb->s_security;
 431         sb->s_security = NULL;
 432         kfree(sbsec);
 433 }
 434
 435 static inline int inode_doinit(struct inode *inode)
 436 {
 437         return inode_doinit_with_dentry(inode, NULL);
 438 }
 439
 440 enum {
 441         Opt_error = -1,
 442         Opt_context = 1,
 443         Opt_fscontext = 2,
 444         Opt_defcontext = 3,
 445         Opt_rootcontext = 4,
 446         Opt_labelsupport = 5,
 447         Opt_nextmntopt = 6,
 448 };
 449
 450 #define NUM_SEL_MNT_OPTS        (Opt_nextmntopt - 1)
 451
 452 static const match_table_t tokens = {
 453         {Opt_context, CONTEXT_STR "%s"},
 454         {Opt_fscontext, FSCONTEXT_STR "%s"},
 455         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 456         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 457         {Opt_labelsupport, LABELSUPP_STR},
 458         {Opt_error, NULL},
 459 };
 460
 461 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 462
 463 static int may_context_mount_sb_relabel(u32 sid,
 464                         struct superblock_security_struct *sbsec,
 465                         const struct cred *cred)
 466 {
 467         const struct task_security_struct *tsec = cred->security;
 468         int rc;
 469
 470         rc = avc_has_perm(&selinux_state,
 471                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 472                           FILESYSTEM__RELABELFROM, NULL);
 473         if (rc)
 474                 return rc;
 475
 476         rc = avc_has_perm(&selinux_state,
 477                           tsec->sid, sid, SECCLASS_FILESYSTEM,
 478                           FILESYSTEM__RELABELTO, NULL);
 479         return rc;
 480 }
 481
 482 static int may_context_mount_inode_relabel(u32 sid,
 483                         struct superblock_security_struct *sbsec,
 484                         const struct cred *cred)
 485 {
 486         const struct task_security_struct *tsec = cred->security;
 487         int rc;
 488         rc = avc_has_perm(&selinux_state,
 489                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 490                           FILESYSTEM__RELABELFROM, NULL);
 491         if (rc)
 492                 return rc;
 493
 494         rc = avc_has_perm(&selinux_state,
 495                           sid, sbsec->sid, SECCLASS_FILESYSTEM,
 496                           FILESYSTEM__ASSOCIATE, NULL);
 497         return rc;
 498 }
 499
 500 static int selinux_is_sblabel_mnt(struct super_block *sb)
 501 {
 502         struct superblock_security_struct *sbsec = sb->s_security;
 503
 504         return sbsec->behavior == SECURITY_FS_USE_XATTR ||
 505                 sbsec->behavior == SECURITY_FS_USE_TRANS ||
 506                 sbsec->behavior == SECURITY_FS_USE_TASK ||
 507                 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
 508                 /* Special handling. Genfs but also in-core setxattr handler */
 509                 !strcmp(sb->s_type->name, "sysfs") ||
 510                 !strcmp(sb->s_type->name, "pstore") ||
 511                 !strcmp(sb->s_type->name, "debugfs") ||
 512                 !strcmp(sb->s_type->name, "tracefs") ||
 513                 !strcmp(sb->s_type->name, "rootfs") ||
 514                 (selinux_policycap_cgroupseclabel() &&
 515                  (!strcmp(sb->s_type->name, "cgroup") ||
 516                   !strcmp(sb->s_type->name, "cgroup2")));
 517 }
 518
 519 static int sb_finish_set_opts(struct super_block *sb)
 520 {
 521         struct superblock_security_struct *sbsec = sb->s_security;
 522         struct dentry *root = sb->s_root;
 523         struct inode *root_inode = d_backing_inode(root);
 524         int rc = 0;
 525
 526         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 527                 /* Make sure that the xattr handler exists and that no
 528                    error other than -ENODATA is returned by getxattr on
 529                    the root directory.  -ENODATA is ok, as this may be
 530                    the first boot of the SELinux kernel before we have
 531                    assigned xattr values to the filesystem. */
 532                 if (!(root_inode->i_opflags & IOP_XATTR)) {
 533                         pr_warn("SELinux: (dev %s, type %s) has no "
 534                                "xattr support\n", sb->s_id, sb->s_type->name);
 535                         rc = -EOPNOTSUPP;
 536                         goto out;
 537                 }
 538
 539                 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 540                 if (rc < 0 && rc != -ENODATA) {
 541                         if (rc == -EOPNOTSUPP)
 542                                 pr_warn("SELinux: (dev %s, type "
 543                                        "%s) has no security xattr handler\n",
 544                                        sb->s_id, sb->s_type->name);
 545                         else
 546                                 pr_warn("SELinux: (dev %s, type "
 547                                        "%s) getxattr errno %d\n", sb->s_id,
 548                                        sb->s_type->name, -rc);
 549                         goto out;
 550                 }
 551         }
 552
 553         sbsec->flags |= SE_SBINITIALIZED;
 554
 555         /*
 556          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 557          * leave the flag untouched because sb_clone_mnt_opts might be handing
 558          * us a superblock that needs the flag to be cleared.
 559          */
 560         if (selinux_is_sblabel_mnt(sb))
 561                 sbsec->flags |= SBLABEL_MNT;
 562         else
 563                 sbsec->flags &= ~SBLABEL_MNT;
 564
 565         /* Initialize the root inode. */
 566         rc = inode_doinit_with_dentry(root_inode, root);
 567
 568         /* Initialize any other inodes associated with the superblock, e.g.
 569            inodes created prior to initial policy load or inodes created
 570            during get_sb by a pseudo filesystem that directly
 571            populates itself. */
 572         spin_lock(&sbsec->isec_lock);
 573 next_inode:
 574         if (!list_empty(&sbsec->isec_head)) {
 575                 struct inode_security_struct *isec =
 576                                 list_entry(sbsec->isec_head.next,
 577                                            struct inode_security_struct, list);
 578                 struct inode *inode = isec->inode;
 579                 list_del_init(&isec->list);
 580                 spin_unlock(&sbsec->isec_lock);
 581                 inode = igrab(inode);
 582                 if (inode) {
 583                         if (!IS_PRIVATE(inode))
 584                                 inode_doinit(inode);
 585                         iput(inode);
 586                 }
 587                 spin_lock(&sbsec->isec_lock);
 588                 goto next_inode;
 589         }
 590         spin_unlock(&sbsec->isec_lock);
 591 out:
 592         return rc;
 593 }
 594
 595 /*
 596  * This function should allow an FS to ask what it's mount security
 597  * options were so it can use those later for submounts, displaying
 598  * mount options, or whatever.
 599  */
 600 static int selinux_get_mnt_opts(const struct super_block *sb,
 601                                 struct security_mnt_opts *opts)
 602 {
 603         int rc = 0, i;
 604         struct superblock_security_struct *sbsec = sb->s_security;
 605         char *context = NULL;
 606         u32 len;
 607         char tmp;
 608
 609         security_init_mnt_opts(opts);
 610
 611         if (!(sbsec->flags & SE_SBINITIALIZED))
 612                 return -EINVAL;
 613
 614         if (!selinux_state.initialized)
 615                 return -EINVAL;
 616
 617         /* make sure we always check enough bits to cover the mask */
 618         BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
 619
 620         tmp = sbsec->flags & SE_MNTMASK;
 621         /* count the number of mount options for this sb */
 622         for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
 623                 if (tmp & 0x01)
 624                         opts->num_mnt_opts++;
 625                 tmp >>= 1;
 626         }
 627         /* Check if the Label support flag is set */
 628         if (sbsec->flags & SBLABEL_MNT)
 629                 opts->num_mnt_opts++;
 630
 631         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 632         if (!opts->mnt_opts) {
 633                 rc = -ENOMEM;
 634                 goto out_free;
 635         }
 636
 637         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 638         if (!opts->mnt_opts_flags) {
 639                 rc = -ENOMEM;
 640                 goto out_free;
 641         }
 642
 643         i = 0;
 644         if (sbsec->flags & FSCONTEXT_MNT) {
 645                 rc = security_sid_to_context(&selinux_state, sbsec->sid,
 646                                              &context, &len);
 647                 if (rc)
 648                         goto out_free;
 649                 opts->mnt_opts[i] = context;
 650                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 651         }
 652         if (sbsec->flags & CONTEXT_MNT) {
 653                 rc = security_sid_to_context(&selinux_state,
 654                                              sbsec->mntpoint_sid,
 655                                              &context, &len);
 656                 if (rc)
 657                         goto out_free;
 658                 opts->mnt_opts[i] = context;
 659                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 660         }
 661         if (sbsec->flags & DEFCONTEXT_MNT) {
 662                 rc = security_sid_to_context(&selinux_state, sbsec->def_sid,
 663                                              &context, &len);
 664                 if (rc)
 665                         goto out_free;
 666                 opts->mnt_opts[i] = context;
 667                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 668         }
 669         if (sbsec->flags & ROOTCONTEXT_MNT) {
 670                 struct dentry *root = sbsec->sb->s_root;
 671                 struct inode_security_struct *isec = backing_inode_security(root);
 672
 673                 rc = security_sid_to_context(&selinux_state, isec->sid,
 674                                              &context, &len);
 675                 if (rc)
 676                         goto out_free;
 677                 opts->mnt_opts[i] = context;
 678                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 679         }
 680         if (sbsec->flags & SBLABEL_MNT) {
 681                 opts->mnt_opts[i] = NULL;
 682                 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
 683         }
 684
 685         BUG_ON(i != opts->num_mnt_opts);
 686
 687         return 0;
 688
 689 out_free:
 690         security_free_mnt_opts(opts);
 691         return rc;
 692 }
 693
 694 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 695                       u32 old_sid, u32 new_sid)
 696 {
 697         char mnt_flags = sbsec->flags & SE_MNTMASK;
 698
 699         /* check if the old mount command had the same options */
 700         if (sbsec->flags & SE_SBINITIALIZED)
 701                 if (!(sbsec->flags & flag) ||
 702                     (old_sid != new_sid))
 703                         return 1;
 704
 705         /* check if we were passed the same options twice,
 706          * aka someone passed context=a,context=b
 707          */
 708         if (!(sbsec->flags & SE_SBINITIALIZED))
 709                 if (mnt_flags & flag)
 710                         return 1;
 711         return 0;
 712 }
 713
 714 /*
 715  * Allow filesystems with binary mount data to explicitly set mount point
 716  * labeling information.
 717  */
 718 static int selinux_set_mnt_opts(struct super_block *sb,
 719                                 struct security_mnt_opts *opts,
 720                                 unsigned long kern_flags,
 721                                 unsigned long *set_kern_flags)
 722 {
 723         const struct cred *cred = current_cred();
 724         int rc = 0, i;
 725         struct superblock_security_struct *sbsec = sb->s_security;
 726         const char *name = sb->s_type->name;
 727         struct dentry *root = sbsec->sb->s_root;
 728         struct inode_security_struct *root_isec;
 729         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 730         u32 defcontext_sid = 0;
 731         char **mount_options = opts->mnt_opts;
 732         int *flags = opts->mnt_opts_flags;
 733         int num_opts = opts->num_mnt_opts;
 734
 735         mutex_lock(&sbsec->lock);
 736
 737         if (!selinux_state.initialized) {
 738                 if (!num_opts) {
 739                         /* Defer initialization until selinux_complete_init,
 740                            after the initial policy is loaded and the security
 741                            server is ready to handle calls. */
 742                         goto out;
 743                 }
 744                 rc = -EINVAL;
 745                 pr_warn("SELinux: Unable to set superblock options "
 746                         "before the security server is initialized\n");
 747                 goto out;
 748         }
 749         if (kern_flags && !set_kern_flags) {
 750                 /* Specifying internal flags without providing a place to
 751                  * place the results is not allowed */
 752                 rc = -EINVAL;
 753                 goto out;
 754         }
 755
 756         /*
 757          * Binary mount data FS will come through this function twice.  Once
 758          * from an explicit call and once from the generic calls from the vfs.
 759          * Since the generic VFS calls will not contain any security mount data
 760          * we need to skip the double mount verification.
 761          *
 762          * This does open a hole in which we will not notice if the first
 763          * mount using this sb set explict options and a second mount using
 764          * this sb does not set any security options.  (The first options
 765          * will be used for both mounts)
 766          */
 767         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 768             && (num_opts == 0))
 769                 goto out;
 770
 771         root_isec = backing_inode_security_novalidate(root);
 772
 773         /*
 774          * parse the mount options, check if they are valid sids.
 775          * also check if someone is trying to mount the same sb more
 776          * than once with different security options.
 777          */
 778         for (i = 0; i < num_opts; i++) {
 779                 u32 sid;
 780
 781                 if (flags[i] == SBLABEL_MNT)
 782                         continue;
 783                 rc = security_context_str_to_sid(&selinux_state,
 784                                                  mount_options[i], &sid,
 785                                                  GFP_KERNEL);
 786                 if (rc) {
 787                         pr_warn("SELinux: security_context_str_to_sid"
 788                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 789                                mount_options[i], sb->s_id, name, rc);
 790                         goto out;
 791                 }
 792                 switch (flags[i]) {
 793                 case FSCONTEXT_MNT:
 794                         fscontext_sid = sid;
 795
 796                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 797                                         fscontext_sid))
 798                                 goto out_double_mount;
 799
 800                         sbsec->flags |= FSCONTEXT_MNT;
 801                         break;
 802                 case CONTEXT_MNT:
 803                         context_sid = sid;
 804
 805                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 806                                         context_sid))
 807                                 goto out_double_mount;
 808
 809                         sbsec->flags |= CONTEXT_MNT;
 810                         break;
 811                 case ROOTCONTEXT_MNT:
 812                         rootcontext_sid = sid;
 813
 814                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 815                                         rootcontext_sid))
 816                                 goto out_double_mount;
 817
 818                         sbsec->flags |= ROOTCONTEXT_MNT;
 819
 820                         break;
 821                 case DEFCONTEXT_MNT:
 822                         defcontext_sid = sid;
 823
 824                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 825                                         defcontext_sid))
 826                                 goto out_double_mount;
 827
 828                         sbsec->flags |= DEFCONTEXT_MNT;
 829
 830                         break;
 831                 default:
 832                         rc = -EINVAL;
 833                         goto out;
 834                 }
 835         }
 836
 837         if (sbsec->flags & SE_SBINITIALIZED) {
 838                 /* previously mounted with options, but not on this attempt? */
 839                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 840                         goto out_double_mount;
 841                 rc = 0;
 842                 goto out;
 843         }
 844
 845         if (strcmp(sb->s_type->name, "proc") == 0)
 846                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 847
 848         if (!strcmp(sb->s_type->name, "debugfs") ||
 849             !strcmp(sb->s_type->name, "tracefs") ||
 850             !strcmp(sb->s_type->name, "sysfs") ||
 851             !strcmp(sb->s_type->name, "pstore") ||
 852             !strcmp(sb->s_type->name, "cgroup") ||
 853             !strcmp(sb->s_type->name, "cgroup2"))
 854                 sbsec->flags |= SE_SBGENFS;
 855
 856         if (!sbsec->behavior) {
 857                 /*
 858                  * Determine the labeling behavior to use for this
 859                  * filesystem type.
 860                  */
 861                 rc = security_fs_use(&selinux_state, sb);
 862                 if (rc) {
 863                         pr_warn("%s: security_fs_use(%s) returned %d\n",
 864                                         __func__, sb->s_type->name, rc);
 865                         goto out;
 866                 }
 867         }
 868
 869         /*
 870          * If this is a user namespace mount and the filesystem type is not
 871          * explicitly whitelisted, then no contexts are allowed on the command
 872          * line and security labels must be ignored.
 873          */
 874         if (sb->s_user_ns != &init_user_ns &&
 875             strcmp(sb->s_type->name, "tmpfs") &&
 876             strcmp(sb->s_type->name, "ramfs") &&
 877             strcmp(sb->s_type->name, "devpts")) {
 878                 if (context_sid || fscontext_sid || rootcontext_sid ||
 879                     defcontext_sid) {
 880                         rc = -EACCES;
 881                         goto out;
 882                 }
 883                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 884                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 885                         rc = security_transition_sid(&selinux_state,
 886                                                      current_sid(),
 887                                                      current_sid(),
 888                                                      SECCLASS_FILE, NULL,
 889                                                      &sbsec->mntpoint_sid);
 890                         if (rc)
 891                                 goto out;
 892                 }
 893                 goto out_set_opts;
 894         }
 895
 896         /* sets the context of the superblock for the fs being mounted. */
 897         if (fscontext_sid) {
 898                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 899                 if (rc)
 900                         goto out;
 901
 902                 sbsec->sid = fscontext_sid;
 903         }
 904
 905         /*
 906          * Switch to using mount point labeling behavior.
 907          * sets the label used on all file below the mountpoint, and will set
 908          * the superblock context if not already set.
 909          */
 910         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 911                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 912                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 913         }
 914
 915         if (context_sid) {
 916                 if (!fscontext_sid) {
 917                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 918                                                           cred);
 919                         if (rc)
 920                                 goto out;
 921                         sbsec->sid = context_sid;
 922                 } else {
 923                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 924                                                              cred);
 925                         if (rc)
 926                                 goto out;
 927                 }
 928                 if (!rootcontext_sid)
 929                         rootcontext_sid = context_sid;
 930
 931                 sbsec->mntpoint_sid = context_sid;
 932                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 933         }
 934
 935         if (rootcontext_sid) {
 936                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 937                                                      cred);
 938                 if (rc)
 939                         goto out;
 940
 941                 root_isec->sid = rootcontext_sid;
 942                 root_isec->initialized = LABEL_INITIALIZED;
 943         }
 944
 945         if (defcontext_sid) {
 946                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 947                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 948                         rc = -EINVAL;
 949                         pr_warn("SELinux: defcontext option is "
 950                                "invalid for this filesystem type\n");
 951                         goto out;
 952                 }
 953
 954                 if (defcontext_sid != sbsec->def_sid) {
 955                         rc = may_context_mount_inode_relabel(defcontext_sid,
 956                                                              sbsec, cred);
 957                         if (rc)
 958                                 goto out;
 959                 }
 960
 961                 sbsec->def_sid = defcontext_sid;
 962         }
 963
 964 out_set_opts:
 965         rc = sb_finish_set_opts(sb);
 966 out:
 967         mutex_unlock(&sbsec->lock);
 968         return rc;
 969 out_double_mount:
 970         rc = -EINVAL;
 971         pr_warn("SELinux: mount invalid.  Same superblock, different "
 972                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 973         goto out;
 974 }
 975
 976 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 977                                     const struct super_block *newsb)
 978 {
 979         struct superblock_security_struct *old = oldsb->s_security;
 980         struct superblock_security_struct *new = newsb->s_security;
 981         char oldflags = old->flags & SE_MNTMASK;
 982         char newflags = new->flags & SE_MNTMASK;
 983
 984         if (oldflags != newflags)
 985                 goto mismatch;
 986         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 987                 goto mismatch;
 988         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 989                 goto mismatch;
 990         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 991                 goto mismatch;
 992         if (oldflags & ROOTCONTEXT_MNT) {
 993                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 994                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 995                 if (oldroot->sid != newroot->sid)
 996                         goto mismatch;
 997         }
 998         return 0;
 999 mismatch:
1000         pr_warn("SELinux: mount invalid.  Same superblock, "
1001                             "different security settings for (dev %s, "
1002                             "type %s)\n", newsb->s_id, newsb->s_type->name);
1003         return -EBUSY;
1004 }
1005
1006 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
1007                                         struct super_block *newsb,
1008                                         unsigned long kern_flags,
1009                                         unsigned long *set_kern_flags)
1010 {
1011         int rc = 0;
1012         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
1013         struct superblock_security_struct *newsbsec = newsb->s_security;
1014
1015         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
1016         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
1017         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
1018
1019         /*
1020          * if the parent was able to be mounted it clearly had no special lsm
1021          * mount options.  thus we can safely deal with this superblock later
1022          */
1023         if (!selinux_state.initialized)
1024                 return 0;
1025
1026         /*
1027          * Specifying internal flags without providing a place to
1028          * place the results is not allowed.
1029          */
1030         if (kern_flags && !set_kern_flags)
1031                 return -EINVAL;
1032
1033         /* how can we clone if the old one wasn't set up?? */
1034         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
1035
1036         /* if fs is reusing a sb, make sure that the contexts match */
1037         if (newsbsec->flags & SE_SBINITIALIZED)
1038                 return selinux_cmp_sb_context(oldsb, newsb);
1039
1040         mutex_lock(&newsbsec->lock);
1041
1042         newsbsec->flags = oldsbsec->flags;
1043
1044         newsbsec->sid = oldsbsec->sid;
1045         newsbsec->def_sid = oldsbsec->def_sid;
1046         newsbsec->behavior = oldsbsec->behavior;
1047
1048         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
1049                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
1050                 rc = security_fs_use(&selinux_state, newsb);
1051                 if (rc)
1052                         goto out;
1053         }
1054
1055         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
1056                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
1057                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
1058         }
1059
1060         if (set_context) {
1061                 u32 sid = oldsbsec->mntpoint_sid;
1062
1063                 if (!set_fscontext)
1064                         newsbsec->sid = sid;
1065                 if (!set_rootcontext) {
1066                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1067                         newisec->sid = sid;
1068                 }
1069                 newsbsec->mntpoint_sid = sid;
1070         }
1071         if (set_rootcontext) {
1072                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
1073                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1074
1075                 newisec->sid = oldisec->sid;
1076         }
1077
1078         sb_finish_set_opts(newsb);
1079 out:
1080         mutex_unlock(&newsbsec->lock);
1081         return rc;
1082 }
1083
1084 static int selinux_parse_opts_str(char *options,
1085                                   struct security_mnt_opts *opts)
1086 {
1087         char *p;
1088         char *context = NULL, *defcontext = NULL;
1089         char *fscontext = NULL, *rootcontext = NULL;
1090         int rc, num_mnt_opts = 0;
1091
1092         opts->num_mnt_opts = 0;
1093
1094         /* Standard string-based options. */
1095         while ((p = strsep(&options, "|")) != NULL) {
1096                 int token;
1097                 substring_t args[MAX_OPT_ARGS];
1098
1099                 if (!*p)
1100                         continue;
1101
1102                 token = match_token(p, tokens, args);
1103
1104                 switch (token) {
1105                 case Opt_context:
1106                         if (context || defcontext) {
1107                                 rc = -EINVAL;
1108                                 pr_warn(SEL_MOUNT_FAIL_MSG);
1109                                 goto out_err;
1110                         }
1111                         context = match_strdup(&args[0]);
1112                         if (!context) {
1113                                 rc = -ENOMEM;
1114                                 goto out_err;
1115                         }
1116                         break;
1117
1118                 case Opt_fscontext:
1119                         if (fscontext) {
1120                                 rc = -EINVAL;
1121                                 pr_warn(SEL_MOUNT_FAIL_MSG);
1122                                 goto out_err;
1123                         }
1124                         fscontext = match_strdup(&args[0]);
1125                         if (!fscontext) {
1126                                 rc = -ENOMEM;
1127                                 goto out_err;
1128                         }
1129                         break;
1130
1131                 case Opt_rootcontext:
1132                         if (rootcontext) {
1133                                 rc = -EINVAL;
1134                                 pr_warn(SEL_MOUNT_FAIL_MSG);
1135                                 goto out_err;
1136                         }
1137                         rootcontext = match_strdup(&args[0]);
1138                         if (!rootcontext) {
1139                                 rc = -ENOMEM;
1140                                 goto out_err;
1141                         }
1142                         break;
1143
1144                 case Opt_defcontext:
1145                         if (context || defcontext) {
1146                                 rc = -EINVAL;
1147                                 pr_warn(SEL_MOUNT_FAIL_MSG);
1148                                 goto out_err;
1149                         }
1150                         defcontext = match_strdup(&args[0]);
1151                         if (!defcontext) {
1152                                 rc = -ENOMEM;
1153                                 goto out_err;
1154                         }
1155                         break;
1156                 case Opt_labelsupport:
1157                         break;
1158                 default:
1159                         rc = -EINVAL;
1160                         pr_warn("SELinux:  unknown mount option\n");
1161                         goto out_err;
1162
1163                 }
1164         }
1165
1166         rc = -ENOMEM;
1167         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1168         if (!opts->mnt_opts)
1169                 goto out_err;
1170
1171         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
1172                                        GFP_KERNEL);
1173         if (!opts->mnt_opts_flags)
1174                 goto out_err;
1175
1176         if (fscontext) {
1177                 opts->mnt_opts[num_mnt_opts] = fscontext;
1178                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1179         }
1180         if (context) {
1181                 opts->mnt_opts[num_mnt_opts] = context;
1182                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1183         }
1184         if (rootcontext) {
1185                 opts->mnt_opts[num_mnt_opts] = rootcontext;
1186                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1187         }
1188         if (defcontext) {
1189                 opts->mnt_opts[num_mnt_opts] = defcontext;
1190                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1191         }
1192
1193         opts->num_mnt_opts = num_mnt_opts;
1194         return 0;
1195
1196 out_err:
1197         security_free_mnt_opts(opts);
1198         kfree(context);
1199         kfree(defcontext);
1200         kfree(fscontext);
1201         kfree(rootcontext);
1202         return rc;
1203 }
1204 /*
1205  * string mount options parsing and call set the sbsec
1206  */
1207 static int superblock_doinit(struct super_block *sb, void *data)
1208 {
1209         int rc = 0;
1210         char *options = data;
1211         struct security_mnt_opts opts;
1212
1213         security_init_mnt_opts(&opts);
1214
1215         if (!data)
1216                 goto out;
1217
1218         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1219
1220         rc = selinux_parse_opts_str(options, &opts);
1221         if (rc)
1222                 goto out_err;
1223
1224 out:
1225         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1226
1227 out_err:
1228         security_free_mnt_opts(&opts);
1229         return rc;
1230 }
1231
1232 static void selinux_write_opts(struct seq_file *m,
1233                                struct security_mnt_opts *opts)
1234 {
1235         int i;
1236         char *prefix;
1237
1238         for (i = 0; i < opts->num_mnt_opts; i++) {
1239                 char *has_comma;
1240
1241                 if (opts->mnt_opts[i])
1242                         has_comma = strchr(opts->mnt_opts[i], ',');
1243                 else
1244                         has_comma = NULL;
1245
1246                 switch (opts->mnt_opts_flags[i]) {
1247                 case CONTEXT_MNT:
1248                         prefix = CONTEXT_STR;
1249                         break;
1250                 case FSCONTEXT_MNT:
1251                         prefix = FSCONTEXT_STR;
1252                         break;
1253                 case ROOTCONTEXT_MNT:
1254                         prefix = ROOTCONTEXT_STR;
1255                         break;
1256                 case DEFCONTEXT_MNT:
1257                         prefix = DEFCONTEXT_STR;
1258                         break;
1259                 case SBLABEL_MNT:
1260                         seq_putc(m, ',');
1261                         seq_puts(m, LABELSUPP_STR);
1262                         continue;
1263                 default:
1264                         BUG();
1265                         return;
1266                 };
1267                 /* we need a comma before each option */
1268                 seq_putc(m, ',');
1269                 seq_puts(m, prefix);
1270                 if (has_comma)
1271                         seq_putc(m, '\"');
1272                 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1273                 if (has_comma)
1274                         seq_putc(m, '\"');
1275         }
1276 }
1277
1278 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1279 {
1280         struct security_mnt_opts opts;
1281         int rc;
1282
1283         rc = selinux_get_mnt_opts(sb, &opts);
1284         if (rc) {
1285                 /* before policy load we may get EINVAL, don't show anything */
1286                 if (rc == -EINVAL)
1287                         rc = 0;
1288                 return rc;
1289         }
1290
1291         selinux_write_opts(m, &opts);
1292
1293         security_free_mnt_opts(&opts);
1294
1295         return rc;
1296 }
1297
1298 static inline u16 inode_mode_to_security_class(umode_t mode)
1299 {
1300         switch (mode & S_IFMT) {
1301         case S_IFSOCK:
1302                 return SECCLASS_SOCK_FILE;
1303         case S_IFLNK:
1304                 return SECCLASS_LNK_FILE;
1305         case S_IFREG:
1306                 return SECCLASS_FILE;
1307         case S_IFBLK:
1308                 return SECCLASS_BLK_FILE;
1309         case S_IFDIR:
1310                 return SECCLASS_DIR;
1311         case S_IFCHR:
1312                 return SECCLASS_CHR_FILE;
1313         case S_IFIFO:
1314                 return SECCLASS_FIFO_FILE;
1315
1316         }
1317
1318         return SECCLASS_FILE;
1319 }
1320
1321 static inline int default_protocol_stream(int protocol)
1322 {
1323         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1324 }
1325
1326 static inline int default_protocol_dgram(int protocol)
1327 {
1328         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1329 }
1330
1331 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1332 {
1333         int extsockclass = selinux_policycap_extsockclass();
1334
1335         switch (family) {
1336         case PF_UNIX:
1337                 switch (type) {
1338                 case SOCK_STREAM:
1339                 case SOCK_SEQPACKET:
1340                         return SECCLASS_UNIX_STREAM_SOCKET;
1341                 case SOCK_DGRAM:
1342                 case SOCK_RAW:
1343                         return SECCLASS_UNIX_DGRAM_SOCKET;
1344                 }
1345                 break;
1346         case PF_INET:
1347         case PF_INET6:
1348                 switch (type) {
1349                 case SOCK_STREAM:
1350                 case SOCK_SEQPACKET:
1351                         if (default_protocol_stream(protocol))
1352                                 return SECCLASS_TCP_SOCKET;
1353                         else if (extsockclass && protocol == IPPROTO_SCTP)
1354                                 return SECCLASS_SCTP_SOCKET;
1355                         else
1356                                 return SECCLASS_RAWIP_SOCKET;
1357                 case SOCK_DGRAM:
1358                         if (default_protocol_dgram(protocol))
1359                                 return SECCLASS_UDP_SOCKET;
1360                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1361                                                   protocol == IPPROTO_ICMPV6))
1362                                 return SECCLASS_ICMP_SOCKET;
1363                         else
1364                                 return SECCLASS_RAWIP_SOCKET;
1365                 case SOCK_DCCP:
1366                         return SECCLASS_DCCP_SOCKET;
1367                 default:
1368                         return SECCLASS_RAWIP_SOCKET;
1369                 }
1370                 break;
1371         case PF_NETLINK:
1372                 switch (protocol) {
1373                 case NETLINK_ROUTE:
1374                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1375                 case NETLINK_SOCK_DIAG:
1376                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1377                 case NETLINK_NFLOG:
1378                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1379                 case NETLINK_XFRM:
1380                         return SECCLASS_NETLINK_XFRM_SOCKET;
1381                 case NETLINK_SELINUX:
1382                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1383                 case NETLINK_ISCSI:
1384                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1385                 case NETLINK_AUDIT:
1386                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1387                 case NETLINK_FIB_LOOKUP:
1388                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1389                 case NETLINK_CONNECTOR:
1390                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1391                 case NETLINK_NETFILTER:
1392                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1393                 case NETLINK_DNRTMSG:
1394                         return SECCLASS_NETLINK_DNRT_SOCKET;
1395                 case NETLINK_KOBJECT_UEVENT:
1396                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1397                 case NETLINK_GENERIC:
1398                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1399                 case NETLINK_SCSITRANSPORT:
1400                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1401                 case NETLINK_RDMA:
1402                         return SECCLASS_NETLINK_RDMA_SOCKET;
1403                 case NETLINK_CRYPTO:
1404                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1405                 default:
1406                         return SECCLASS_NETLINK_SOCKET;
1407                 }
1408         case PF_PACKET:
1409                 return SECCLASS_PACKET_SOCKET;
1410         case PF_KEY:
1411                 return SECCLASS_KEY_SOCKET;
1412         case PF_APPLETALK:
1413                 return SECCLASS_APPLETALK_SOCKET;
1414         }
1415
1416         if (extsockclass) {
1417                 switch (family) {
1418                 case PF_AX25:
1419                         return SECCLASS_AX25_SOCKET;
1420                 case PF_IPX:
1421                         return SECCLASS_IPX_SOCKET;
1422                 case PF_NETROM:
1423                         return SECCLASS_NETROM_SOCKET;
1424                 case PF_ATMPVC:
1425                         return SECCLASS_ATMPVC_SOCKET;
1426                 case PF_X25:
1427                         return SECCLASS_X25_SOCKET;
1428                 case PF_ROSE:
1429                         return SECCLASS_ROSE_SOCKET;
1430                 case PF_DECnet:
1431                         return SECCLASS_DECNET_SOCKET;
1432                 case PF_ATMSVC:
1433                         return SECCLASS_ATMSVC_SOCKET;
1434                 case PF_RDS:
1435                         return SECCLASS_RDS_SOCKET;
1436                 case PF_IRDA:
1437                         return SECCLASS_IRDA_SOCKET;
1438                 case PF_PPPOX:
1439                         return SECCLASS_PPPOX_SOCKET;
1440                 case PF_LLC:
1441                         return SECCLASS_LLC_SOCKET;
1442                 case PF_CAN:
1443                         return SECCLASS_CAN_SOCKET;
1444                 case PF_TIPC:
1445                         return SECCLASS_TIPC_SOCKET;
1446                 case PF_BLUETOOTH:
1447                         return SECCLASS_BLUETOOTH_SOCKET;
1448                 case PF_IUCV:
1449                         return SECCLASS_IUCV_SOCKET;
1450                 case PF_RXRPC:
1451                         return SECCLASS_RXRPC_SOCKET;
1452                 case PF_ISDN:
1453                         return SECCLASS_ISDN_SOCKET;
1454                 case PF_PHONET:
1455                         return SECCLASS_PHONET_SOCKET;
1456                 case PF_IEEE802154:
1457                         return SECCLASS_IEEE802154_SOCKET;
1458                 case PF_CAIF:
1459                         return SECCLASS_CAIF_SOCKET;
1460                 case PF_ALG:
1461                         return SECCLASS_ALG_SOCKET;
1462                 case PF_NFC:
1463                         return SECCLASS_NFC_SOCKET;
1464                 case PF_VSOCK:
1465                         return SECCLASS_VSOCK_SOCKET;
1466                 case PF_KCM:
1467                         return SECCLASS_KCM_SOCKET;
1468                 case PF_QIPCRTR:
1469                         return SECCLASS_QIPCRTR_SOCKET;
1470                 case PF_SMC:
1471                         return SECCLASS_SMC_SOCKET;
1472                 case PF_XDP:
1473                         return SECCLASS_XDP_SOCKET;
1474 #if PF_MAX > 45
1475 #error New address family defined, please update this function.
1476 #endif
1477                 }
1478         }
1479
1480         return SECCLASS_SOCKET;
1481 }
1482
1483 static int selinux_genfs_get_sid(struct dentry *dentry,
1484                                  u16 tclass,
1485                                  u16 flags,
1486                                  u32 *sid)
1487 {
1488         int rc;
1489         struct super_block *sb = dentry->d_sb;
1490         char *buffer, *path;
1491
1492         buffer = (char *)__get_free_page(GFP_KERNEL);
1493         if (!buffer)
1494                 return -ENOMEM;
1495
1496         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1497         if (IS_ERR(path))
1498                 rc = PTR_ERR(path);
1499         else {
1500                 if (flags & SE_SBPROC) {
1501                         /* each process gets a /proc/PID/ entry. Strip off the
1502                          * PID part to get a valid selinux labeling.
1503                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1504                         while (path[1] >= '0' && path[1] <= '9') {
1505                                 path[1] = '/';
1506                                 path++;
1507                         }
1508                 }
1509                 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1510                                         path, tclass, sid);
1511         }
1512         free_page((unsigned long)buffer);
1513         return rc;
1514 }
1515
1516 /* The inode's security attributes must be initialized before first use. */
1517 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1518 {
1519         struct superblock_security_struct *sbsec = NULL;
1520         struct inode_security_struct *isec = inode->i_security;
1521         u32 task_sid, sid = 0;
1522         u16 sclass;
1523         struct dentry *dentry;
1524 #define INITCONTEXTLEN 255
1525         char *context = NULL;
1526         unsigned len = 0;
1527         int rc = 0;
1528
1529         if (isec->initialized == LABEL_INITIALIZED)
1530                 return 0;
1531
1532         spin_lock(&isec->lock);
1533         if (isec->initialized == LABEL_INITIALIZED)
1534                 goto out_unlock;
1535
1536         if (isec->sclass == SECCLASS_FILE)
1537                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1538
1539         sbsec = inode->i_sb->s_security;
1540         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1541                 /* Defer initialization until selinux_complete_init,
1542                    after the initial policy is loaded and the security
1543                    server is ready to handle calls. */
1544                 spin_lock(&sbsec->isec_lock);
1545                 if (list_empty(&isec->list))
1546                         list_add(&isec->list, &sbsec->isec_head);
1547                 spin_unlock(&sbsec->isec_lock);
1548                 goto out_unlock;
1549         }
1550
1551         sclass = isec->sclass;
1552         task_sid = isec->task_sid;
1553         sid = isec->sid;
1554         isec->initialized = LABEL_PENDING;
1555         spin_unlock(&isec->lock);
1556
1557         switch (sbsec->behavior) {
1558         case SECURITY_FS_USE_NATIVE:
1559                 break;
1560         case SECURITY_FS_USE_XATTR:
1561                 if (!(inode->i_opflags & IOP_XATTR)) {
1562                         sid = sbsec->def_sid;
1563                         break;
1564                 }
1565                 /* Need a dentry, since the xattr API requires one.
1566                    Life would be simpler if we could just pass the inode. */
1567                 if (opt_dentry) {
1568                         /* Called from d_instantiate or d_splice_alias. */
1569                         dentry = dget(opt_dentry);
1570                 } else {
1571                         /*
1572                          * Called from selinux_complete_init, try to find a dentry.
1573                          * Some filesystems really want a connected one, so try
1574                          * that first.  We could split SECURITY_FS_USE_XATTR in
1575                          * two, depending upon that...
1576                          */
1577                         dentry = d_find_alias(inode);
1578                         if (!dentry)
1579                                 dentry = d_find_any_alias(inode);
1580                 }
1581                 if (!dentry) {
1582                         /*
1583                          * this is can be hit on boot when a file is accessed
1584                          * before the policy is loaded.  When we load policy we
1585                          * may find inodes that have no dentry on the
1586                          * sbsec->isec_head list.  No reason to complain as these
1587                          * will get fixed up the next time we go through
1588                          * inode_doinit with a dentry, before these inodes could
1589                          * be used again by userspace.
1590                          */
1591                         goto out;
1592                 }
1593
1594                 len = INITCONTEXTLEN;
1595                 context = kmalloc(len+1, GFP_NOFS);
1596                 if (!context) {
1597                         rc = -ENOMEM;
1598                         dput(dentry);
1599                         goto out;
1600                 }
1601                 context[len] = '\0';
1602                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1603                 if (rc == -ERANGE) {
1604                         kfree(context);
1605
1606                         /* Need a larger buffer.  Query for the right size. */
1607                         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1608                         if (rc < 0) {
1609                                 dput(dentry);
1610                                 goto out;
1611                         }
1612                         len = rc;
1613                         context = kmalloc(len+1, GFP_NOFS);
1614                         if (!context) {
1615                                 rc = -ENOMEM;
1616                                 dput(dentry);
1617                                 goto out;
1618                         }
1619                         context[len] = '\0';
1620                         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1621                 }
1622                 dput(dentry);
1623                 if (rc < 0) {
1624                         if (rc != -ENODATA) {
1625                                 pr_warn("SELinux: %s:  getxattr returned "
1626                                        "%d for dev=%s ino=%ld\n", __func__,
1627                                        -rc, inode->i_sb->s_id, inode->i_ino);
1628                                 kfree(context);
1629                                 goto out;
1630                         }
1631                         /* Map ENODATA to the default file SID */
1632                         sid = sbsec->def_sid;
1633                         rc = 0;
1634                 } else {
1635                         rc = security_context_to_sid_default(&selinux_state,
1636                                                              context, rc, &sid,
1637                                                              sbsec->def_sid,
1638                                                              GFP_NOFS);
1639                         if (rc) {
1640                                 char *dev = inode->i_sb->s_id;
1641                                 unsigned long ino = inode->i_ino;
1642
1643                                 if (rc == -EINVAL) {
1644                                         if (printk_ratelimit())
1645                                                 pr_notice("SELinux: inode=%lu on dev=%s was found to have an invalid "
1646                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1647                                                         "filesystem in question.\n", ino, dev, context);
1648                                 } else {
1649                                         pr_warn("SELinux: %s:  context_to_sid(%s) "
1650                                                "returned %d for dev=%s ino=%ld\n",
1651                                                __func__, context, -rc, dev, ino);
1652                                 }
1653                                 kfree(context);
1654                                 /* Leave with the unlabeled SID */
1655                                 rc = 0;
1656                                 break;
1657                         }
1658                 }
1659                 kfree(context);
1660                 break;
1661         case SECURITY_FS_USE_TASK:
1662                 sid = task_sid;
1663                 break;
1664         case SECURITY_FS_USE_TRANS:
1665                 /* Default to the fs SID. */
1666                 sid = sbsec->sid;
1667
1668                 /* Try to obtain a transition SID. */
1669                 rc = security_transition_sid(&selinux_state, task_sid, sid,
1670                                              sclass, NULL, &sid);
1671                 if (rc)
1672                         goto out;
1673                 break;
1674         case SECURITY_FS_USE_MNTPOINT:
1675                 sid = sbsec->mntpoint_sid;
1676                 break;
1677         default:
1678                 /* Default to the fs superblock SID. */
1679                 sid = sbsec->sid;
1680
1681                 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1682                         /* We must have a dentry to determine the label on
1683                          * procfs inodes */
1684                         if (opt_dentry) {
1685                                 /* Called from d_instantiate or
1686                                  * d_splice_alias. */
1687                                 dentry = dget(opt_dentry);
1688                         } else {
1689                                 /* Called from selinux_complete_init, try to
1690                                  * find a dentry.  Some filesystems really want
1691                                  * a connected one, so try that first.
1692                                  */
1693                                 dentry = d_find_alias(inode);
1694                                 if (!dentry)
1695                                         dentry = d_find_any_alias(inode);
1696                         }
1697                         /*
1698                          * This can be hit on boot when a file is accessed
1699                          * before the policy is loaded.  When we load policy we
1700                          * may find inodes that have no dentry on the
1701                          * sbsec->isec_head list.  No reason to complain as
1702                          * these will get fixed up the next time we go through
1703                          * inode_doinit() with a dentry, before these inodes
1704                          * could be used again by userspace.
1705                          */
1706                         if (!dentry)
1707                                 goto out;
1708                         rc = selinux_genfs_get_sid(dentry, sclass,
1709                                                    sbsec->flags, &sid);
1710                         dput(dentry);
1711                         if (rc)
1712                                 goto out;
1713                 }
1714                 break;
1715         }
1716
1717 out:
1718         spin_lock(&isec->lock);
1719         if (isec->initialized == LABEL_PENDING) {
1720                 if (!sid || rc) {
1721                         isec->initialized = LABEL_INVALID;
1722                         goto out_unlock;
1723                 }
1724
1725                 isec->initialized = LABEL_INITIALIZED;
1726                 isec->sid = sid;
1727         }
1728
1729 out_unlock:
1730         spin_unlock(&isec->lock);
1731         return rc;
1732 }
1733
1734 /* Convert a Linux signal to an access vector. */
1735 static inline u32 signal_to_av(int sig)
1736 {
1737         u32 perm = 0;
1738
1739         switch (sig) {
1740         case SIGCHLD:
1741                 /* Commonly granted from child to parent. */
1742                 perm = PROCESS__SIGCHLD;
1743                 break;
1744         case SIGKILL:
1745                 /* Cannot be caught or ignored */
1746                 perm = PROCESS__SIGKILL;
1747                 break;
1748         case SIGSTOP:
1749                 /* Cannot be caught or ignored */
1750                 perm = PROCESS__SIGSTOP;
1751                 break;
1752         default:
1753                 /* All other signals. */
1754                 perm = PROCESS__SIGNAL;
1755                 break;
1756         }
1757
1758         return perm;
1759 }
1760
1761 #if CAP_LAST_CAP > 63
1762 #error Fix SELinux to handle capabilities > 63.
1763 #endif
1764
1765 /* Check whether a task is allowed to use a capability. */
1766 static int cred_has_capability(const struct cred *cred,
1767                                int cap, int audit, bool initns)
1768 {
1769         struct common_audit_data ad;
1770         struct av_decision avd;
1771         u16 sclass;
1772         u32 sid = cred_sid(cred);
1773         u32 av = CAP_TO_MASK(cap);
1774         int rc;
1775
1776         ad.type = LSM_AUDIT_DATA_CAP;
1777         ad.u.cap = cap;
1778
1779         switch (CAP_TO_INDEX(cap)) {
1780         case 0:
1781                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1782                 break;
1783         case 1:
1784                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1785                 break;
1786         default:
1787                 pr_err("SELinux:  out of range capability %d\n", cap);
1788                 BUG();
1789                 return -EINVAL;
1790         }
1791
1792         rc = avc_has_perm_noaudit(&selinux_state,
1793                                   sid, sid, sclass, av, 0, &avd);
1794         if (audit == SECURITY_CAP_AUDIT) {
1795                 int rc2 = avc_audit(&selinux_state,
1796                                     sid, sid, sclass, av, &avd, rc, &ad, 0);
1797                 if (rc2)
1798                         return rc2;
1799         }
1800         return rc;
1801 }
1802
1803 /* Check whether a task has a particular permission to an inode.
1804    The 'adp' parameter is optional and allows other audit
1805    data to be passed (e.g. the dentry). */
1806 static int inode_has_perm(const struct cred *cred,
1807                           struct inode *inode,
1808                           u32 perms,
1809                           struct common_audit_data *adp)
1810 {
1811         struct inode_security_struct *isec;
1812         u32 sid;
1813
1814         validate_creds(cred);
1815
1816         if (unlikely(IS_PRIVATE(inode)))
1817                 return 0;
1818
1819         sid = cred_sid(cred);
1820         isec = inode->i_security;
1821
1822         return avc_has_perm(&selinux_state,
1823                             sid, isec->sid, isec->sclass, perms, adp);
1824 }
1825
1826 /* Same as inode_has_perm, but pass explicit audit data containing
1827    the dentry to help the auditing code to more easily generate the
1828    pathname if needed. */
1829 static inline int dentry_has_perm(const struct cred *cred,
1830                                   struct dentry *dentry,
1831                                   u32 av)
1832 {
1833         struct inode *inode = d_backing_inode(dentry);
1834         struct common_audit_data ad;
1835
1836         ad.type = LSM_AUDIT_DATA_DENTRY;
1837         ad.u.dentry = dentry;
1838         __inode_security_revalidate(inode, dentry, true);
1839         return inode_has_perm(cred, inode, av, &ad);
1840 }
1841
1842 /* Same as inode_has_perm, but pass explicit audit data containing
1843    the path to help the auditing code to more easily generate the
1844    pathname if needed. */
1845 static inline int path_has_perm(const struct cred *cred,
1846                                 const struct path *path,
1847                                 u32 av)
1848 {
1849         struct inode *inode = d_backing_inode(path->dentry);
1850         struct common_audit_data ad;
1851
1852         ad.type = LSM_AUDIT_DATA_PATH;
1853         ad.u.path = *path;
1854         __inode_security_revalidate(inode, path->dentry, true);
1855         return inode_has_perm(cred, inode, av, &ad);
1856 }
1857
1858 /* Same as path_has_perm, but uses the inode from the file struct. */
1859 static inline int file_path_has_perm(const struct cred *cred,
1860                                      struct file *file,
1861                                      u32 av)
1862 {
1863         struct common_audit_data ad;
1864
1865         ad.type = LSM_AUDIT_DATA_FILE;
1866         ad.u.file = file;
1867         return inode_has_perm(cred, file_inode(file), av, &ad);
1868 }
1869
1870 #ifdef CONFIG_BPF_SYSCALL
1871 static int bpf_fd_pass(struct file *file, u32 sid);
1872 #endif
1873
1874 /* Check whether a task can use an open file descriptor to
1875    access an inode in a given way.  Check access to the
1876    descriptor itself, and then use dentry_has_perm to
1877    check a particular permission to the file.
1878    Access to the descriptor is implicitly granted if it
1879    has the same SID as the process.  If av is zero, then
1880    access to the file is not checked, e.g. for cases
1881    where only the descriptor is affected like seek. */
1882 static int file_has_perm(const struct cred *cred,
1883                          struct file *file,
1884                          u32 av)
1885 {
1886         struct file_security_struct *fsec = file->f_security;
1887         struct inode *inode = file_inode(file);
1888         struct common_audit_data ad;
1889         u32 sid = cred_sid(cred);
1890         int rc;
1891
1892         ad.type = LSM_AUDIT_DATA_FILE;
1893         ad.u.file = file;
1894
1895         if (sid != fsec->sid) {
1896                 rc = avc_has_perm(&selinux_state,
1897                                   sid, fsec->sid,
1898                                   SECCLASS_FD,
1899                                   FD__USE,
1900                                   &ad);
1901                 if (rc)
1902                         goto out;
1903         }
1904
1905 #ifdef CONFIG_BPF_SYSCALL
1906         rc = bpf_fd_pass(file, cred_sid(cred));
1907         if (rc)
1908                 return rc;
1909 #endif
1910
1911         /* av is zero if only checking access to the descriptor. */
1912         rc = 0;
1913         if (av)
1914                 rc = inode_has_perm(cred, inode, av, &ad);
1915
1916 out:
1917         return rc;
1918 }
1919
1920 /*
1921  * Determine the label for an inode that might be unioned.
1922  */
1923 static int
1924 selinux_determine_inode_label(const struct task_security_struct *tsec,
1925                                  struct inode *dir,
1926                                  const struct qstr *name, u16 tclass,
1927                                  u32 *_new_isid)
1928 {
1929         const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1930
1931         if ((sbsec->flags & SE_SBINITIALIZED) &&
1932             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1933                 *_new_isid = sbsec->mntpoint_sid;
1934         } else if ((sbsec->flags & SBLABEL_MNT) &&
1935                    tsec->create_sid) {
1936                 *_new_isid = tsec->create_sid;
1937         } else {
1938                 const struct inode_security_struct *dsec = inode_security(dir);
1939                 return security_transition_sid(&selinux_state, tsec->sid,
1940                                                dsec->sid, tclass,
1941                                                name, _new_isid);
1942         }
1943
1944         return 0;
1945 }
1946
1947 /* Check whether a task can create a file. */
1948 static int may_create(struct inode *dir,
1949                       struct dentry *dentry,
1950                       u16 tclass)
1951 {
1952         const struct task_security_struct *tsec = current_security();
1953         struct inode_security_struct *dsec;
1954         struct superblock_security_struct *sbsec;
1955         u32 sid, newsid;
1956         struct common_audit_data ad;
1957         int rc;
1958
1959         dsec = inode_security(dir);
1960         sbsec = dir->i_sb->s_security;
1961
1962         sid = tsec->sid;
1963
1964         ad.type = LSM_AUDIT_DATA_DENTRY;
1965         ad.u.dentry = dentry;
1966
1967         rc = avc_has_perm(&selinux_state,
1968                           sid, dsec->sid, SECCLASS_DIR,
1969                           DIR__ADD_NAME | DIR__SEARCH,
1970                           &ad);
1971         if (rc)
1972                 return rc;
1973
1974         rc = selinux_determine_inode_label(current_security(), dir,
1975                                            &dentry->d_name, tclass, &newsid);
1976         if (rc)
1977                 return rc;
1978
1979         rc = avc_has_perm(&selinux_state,
1980                           sid, newsid, tclass, FILE__CREATE, &ad);
1981         if (rc)
1982                 return rc;
1983
1984         return avc_has_perm(&selinux_state,
1985                             newsid, sbsec->sid,
1986                             SECCLASS_FILESYSTEM,
1987                             FILESYSTEM__ASSOCIATE, &ad);
1988 }
1989
1990 #define MAY_LINK        0
1991 #define MAY_UNLINK      1
1992 #define MAY_RMDIR       2
1993
1994 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1995 static int may_link(struct inode *dir,
1996                     struct dentry *dentry,
1997                     int kind)
1998
1999 {
2000         struct inode_security_struct *dsec, *isec;
2001         struct common_audit_data ad;
2002         u32 sid = current_sid();
2003         u32 av;
2004         int rc;
2005
2006         dsec = inode_security(dir);
2007         isec = backing_inode_security(dentry);
2008
2009         ad.type = LSM_AUDIT_DATA_DENTRY;
2010         ad.u.dentry = dentry;
2011
2012         av = DIR__SEARCH;
2013         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
2014         rc = avc_has_perm(&selinux_state,
2015                           sid, dsec->sid, SECCLASS_DIR, av, &ad);
2016         if (rc)
2017                 return rc;
2018
2019         switch (kind) {
2020         case MAY_LINK:
2021                 av = FILE__LINK;
2022                 break;
2023         case MAY_UNLINK:
2024                 av = FILE__UNLINK;
2025                 break;
2026         case MAY_RMDIR:
2027                 av = DIR__RMDIR;
2028                 break;
2029         default:
2030                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
2031                         __func__, kind);
2032                 return 0;
2033         }
2034
2035         rc = avc_has_perm(&selinux_state,
2036                           sid, isec->sid, isec->sclass, av, &ad);
2037         return rc;
2038 }
2039
2040 static inline int may_rename(struct inode *old_dir,
2041                              struct dentry *old_dentry,
2042                              struct inode *new_dir,
2043                              struct dentry *new_dentry)
2044 {
2045         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
2046         struct common_audit_data ad;
2047         u32 sid = current_sid();
2048         u32 av;
2049         int old_is_dir, new_is_dir;
2050         int rc;
2051
2052         old_dsec = inode_security(old_dir);
2053         old_isec = backing_inode_security(old_dentry);
2054         old_is_dir = d_is_dir(old_dentry);
2055         new_dsec = inode_security(new_dir);
2056
2057         ad.type = LSM_AUDIT_DATA_DENTRY;
2058
2059         ad.u.dentry = old_dentry;
2060         rc = avc_has_perm(&selinux_state,
2061                           sid, old_dsec->sid, SECCLASS_DIR,
2062                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
2063         if (rc)
2064                 return rc;
2065         rc = avc_has_perm(&selinux_state,
2066                           sid, old_isec->sid,
2067                           old_isec->sclass, FILE__RENAME, &ad);
2068         if (rc)
2069                 return rc;
2070         if (old_is_dir && new_dir != old_dir) {
2071                 rc = avc_has_perm(&selinux_state,
2072                                   sid, old_isec->sid,
2073                                   old_isec->sclass, DIR__REPARENT, &ad);
2074                 if (rc)
2075                         return rc;
2076         }
2077
2078         ad.u.dentry = new_dentry;
2079         av = DIR__ADD_NAME | DIR__SEARCH;
2080         if (d_is_positive(new_dentry))
2081                 av |= DIR__REMOVE_NAME;
2082         rc = avc_has_perm(&selinux_state,
2083                           sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
2084         if (rc)
2085                 return rc;
2086         if (d_is_positive(new_dentry)) {
2087                 new_isec = backing_inode_security(new_dentry);
2088                 new_is_dir = d_is_dir(new_dentry);
2089                 rc = avc_has_perm(&selinux_state,
2090                                   sid, new_isec->sid,
2091                                   new_isec->sclass,
2092                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
2093                 if (rc)
2094                         return rc;
2095         }
2096
2097         return 0;
2098 }
2099
2100 /* Check whether a task can perform a filesystem operation. */
2101 static int superblock_has_perm(const struct cred *cred,
2102                                struct super_block *sb,
2103                                u32 perms,
2104                                struct common_audit_data *ad)
2105 {
2106         struct superblock_security_struct *sbsec;
2107         u32 sid = cred_sid(cred);
2108
2109         sbsec = sb->s_security;
2110         return avc_has_perm(&selinux_state,
2111                             sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
2112 }
2113
2114 /* Convert a Linux mode and permission mask to an access vector. */
2115 static inline u32 file_mask_to_av(int mode, int mask)
2116 {
2117         u32 av = 0;
2118
2119         if (!S_ISDIR(mode)) {
2120                 if (mask & MAY_EXEC)
2121                         av |= FILE__EXECUTE;
2122                 if (mask & MAY_READ)
2123                         av |= FILE__READ;
2124
2125                 if (mask & MAY_APPEND)
2126                         av |= FILE__APPEND;
2127                 else if (mask & MAY_WRITE)
2128                         av |= FILE__WRITE;
2129
2130         } else {
2131                 if (mask & MAY_EXEC)
2132                         av |= DIR__SEARCH;
2133                 if (mask & MAY_WRITE)
2134                         av |= DIR__WRITE;
2135                 if (mask & MAY_READ)
2136                         av |= DIR__READ;
2137         }
2138
2139         return av;
2140 }
2141
2142 /* Convert a Linux file to an access vector. */
2143 static inline u32 file_to_av(struct file *file)
2144 {
2145         u32 av = 0;
2146
2147         if (file->f_mode & FMODE_READ)
2148                 av |= FILE__READ;
2149         if (file->f_mode & FMODE_WRITE) {
2150                 if (file->f_flags & O_APPEND)
2151                         av |= FILE__APPEND;
2152                 else
2153                         av |= FILE__WRITE;
2154         }
2155         if (!av) {
2156                 /*
2157                  * Special file opened with flags 3 for ioctl-only use.
2158                  */
2159                 av = FILE__IOCTL;
2160         }
2161
2162         return av;
2163 }
2164
2165 /*
2166  * Convert a file to an access vector and include the correct open
2167  * open permission.
2168  */
2169 static inline u32 open_file_to_av(struct file *file)
2170 {
2171         u32 av = file_to_av(file);
2172         struct inode *inode = file_inode(file);
2173
2174         if (selinux_policycap_openperm() &&
2175             inode->i_sb->s_magic != SOCKFS_MAGIC)
2176                 av |= FILE__OPEN;
2177
2178         return av;
2179 }
2180
2181 /* Hook functions begin here. */
2182
2183 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2184 {
2185         u32 mysid = current_sid();
2186         u32 mgrsid = task_sid(mgr);
2187
2188         return avc_has_perm(&selinux_state,
2189                             mysid, mgrsid, SECCLASS_BINDER,
2190                             BINDER__SET_CONTEXT_MGR, NULL);
2191 }
2192
2193 static int selinux_binder_transaction(struct task_struct *from,
2194                                       struct task_struct *to)
2195 {
2196         u32 mysid = current_sid();
2197         u32 fromsid = task_sid(from);
2198         u32 tosid = task_sid(to);
2199         int rc;
2200
2201         if (mysid != fromsid) {
2202                 rc = avc_has_perm(&selinux_state,
2203                                   mysid, fromsid, SECCLASS_BINDER,
2204                                   BINDER__IMPERSONATE, NULL);
2205                 if (rc)
2206                         return rc;
2207         }
2208
2209         return avc_has_perm(&selinux_state,
2210                             fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2211                             NULL);
2212 }
2213
2214 static int selinux_binder_transfer_binder(struct task_struct *from,
2215                                           struct task_struct *to)
2216 {
2217         u32 fromsid = task_sid(from);
2218         u32 tosid = task_sid(to);
2219
2220         return avc_has_perm(&selinux_state,
2221                             fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2222                             NULL);
2223 }
2224
2225 static int selinux_binder_transfer_file(struct task_struct *from,
2226                                         struct task_struct *to,
2227                                         struct file *file)
2228 {
2229         u32 sid = task_sid(to);
2230         struct file_security_struct *fsec = file->f_security;
2231         struct dentry *dentry = file->f_path.dentry;
2232         struct inode_security_struct *isec;
2233         struct common_audit_data ad;
2234         int rc;
2235
2236         ad.type = LSM_AUDIT_DATA_PATH;
2237         ad.u.path = file->f_path;
2238
2239         if (sid != fsec->sid) {
2240                 rc = avc_has_perm(&selinux_state,
2241                                   sid, fsec->sid,
2242                                   SECCLASS_FD,
2243                                   FD__USE,
2244                                   &ad);
2245                 if (rc)
2246                         return rc;
2247         }
2248
2249 #ifdef CONFIG_BPF_SYSCALL
2250         rc = bpf_fd_pass(file, sid);
2251         if (rc)
2252                 return rc;
2253 #endif
2254
2255         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2256                 return 0;
2257
2258         isec = backing_inode_security(dentry);
2259         return avc_has_perm(&selinux_state,
2260                             sid, isec->sid, isec->sclass, file_to_av(file),
2261                             &ad);
2262 }
2263
2264 static int selinux_ptrace_access_check(struct task_struct *child,
2265                                      unsigned int mode)
2266 {
2267         u32 sid = current_sid();
2268         u32 csid = task_sid(child);
2269
2270         if (mode & PTRACE_MODE_READ)
2271                 return avc_has_perm(&selinux_state,
2272                                     sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2273
2274         return avc_has_perm(&selinux_state,
2275                             sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2276 }
2277
2278 static int selinux_ptrace_traceme(struct task_struct *parent)
2279 {
2280         return avc_has_perm(&selinux_state,
2281                             task_sid(parent), current_sid(), SECCLASS_PROCESS,
2282                             PROCESS__PTRACE, NULL);
2283 }
2284
2285 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2286                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2287 {
2288         return avc_has_perm(&selinux_state,
2289                             current_sid(), task_sid(target), SECCLASS_PROCESS,
2290                             PROCESS__GETCAP, NULL);
2291 }
2292
2293 static int selinux_capset(struct cred *new, const struct cred *old,
2294                           const kernel_cap_t *effective,
2295                           const kernel_cap_t *inheritable,
2296                           const kernel_cap_t *permitted)
2297 {
2298         return avc_has_perm(&selinux_state,
2299                             cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2300                             PROCESS__SETCAP, NULL);
2301 }
2302
2303 /*
2304  * (This comment used to live with the selinux_task_setuid hook,
2305  * which was removed).
2306  *
2307  * Since setuid only affects the current process, and since the SELinux
2308  * controls are not based on the Linux identity attributes, SELinux does not
2309  * need to control this operation.  However, SELinux does control the use of
2310  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2311  */
2312
2313 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2314                            int cap, int audit)
2315 {
2316         return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2317 }
2318
2319 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2320 {
2321         const struct cred *cred = current_cred();
2322         int rc = 0;
2323
2324         if (!sb)
2325                 return 0;
2326
2327         switch (cmds) {
2328         case Q_SYNC:
2329         case Q_QUOTAON:
2330         case Q_QUOTAOFF:
2331         case Q_SETINFO:
2332         case Q_SETQUOTA:
2333                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2334                 break;
2335         case Q_GETFMT:
2336         case Q_GETINFO:
2337         case Q_GETQUOTA:
2338                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2339                 break;
2340         default:
2341                 rc = 0;  /* let the kernel handle invalid cmds */
2342                 break;
2343         }
2344         return rc;
2345 }
2346
2347 static int selinux_quota_on(struct dentry *dentry)
2348 {
2349         const struct cred *cred = current_cred();
2350
2351         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2352 }
2353
2354 static int selinux_syslog(int type)
2355 {
2356         switch (type) {
2357         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2358         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2359                 return avc_has_perm(&selinux_state,
2360                                     current_sid(), SECINITSID_KERNEL,
2361                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2362         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2363         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2364         /* Set level of messages printed to console */
2365         case SYSLOG_ACTION_CONSOLE_LEVEL:
2366                 return avc_has_perm(&selinux_state,
2367                                     current_sid(), SECINITSID_KERNEL,
2368                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2369                                     NULL);
2370         }
2371         /* All other syslog types */
2372         return avc_has_perm(&selinux_state,
2373                             current_sid(), SECINITSID_KERNEL,
2374                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2375 }
2376
2377 /*
2378  * Check that a process has enough memory to allocate a new virtual
2379  * mapping. 0 means there is enough memory for the allocation to
2380  * succeed and -ENOMEM implies there is not.
2381  *
2382  * Do not audit the selinux permission check, as this is applied to all
2383  * processes that allocate mappings.
2384  */
2385 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2386 {
2387         int rc, cap_sys_admin = 0;
2388
2389         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2390                                  SECURITY_CAP_NOAUDIT, true);
2391         if (rc == 0)
2392                 cap_sys_admin = 1;
2393
2394         return cap_sys_admin;
2395 }
2396
2397 /* binprm security operations */
2398
2399 static u32 ptrace_parent_sid(void)
2400 {
2401         u32 sid = 0;
2402         struct task_struct *tracer;
2403
2404         rcu_read_lock();
2405         tracer = ptrace_parent(current);
2406         if (tracer)
2407                 sid = task_sid(tracer);
2408         rcu_read_unlock();
2409
2410         return sid;
2411 }
2412
2413 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2414                             const struct task_security_struct *old_tsec,
2415                             const struct task_security_struct *new_tsec)
2416 {
2417         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2418         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2419         int rc;
2420         u32 av;
2421
2422         if (!nnp && !nosuid)
2423                 return 0; /* neither NNP nor nosuid */
2424
2425         if (new_tsec->sid == old_tsec->sid)
2426                 return 0; /* No change in credentials */
2427
2428         /*
2429          * If the policy enables the nnp_nosuid_transition policy capability,
2430          * then we permit transitions under NNP or nosuid if the
2431          * policy allows the corresponding permission between
2432          * the old and new contexts.
2433          */
2434         if (selinux_policycap_nnp_nosuid_transition()) {
2435                 av = 0;
2436                 if (nnp)
2437                         av |= PROCESS2__NNP_TRANSITION;
2438                 if (nosuid)
2439                         av |= PROCESS2__NOSUID_TRANSITION;
2440                 rc = avc_has_perm(&selinux_state,
2441                                   old_tsec->sid, new_tsec->sid,
2442                                   SECCLASS_PROCESS2, av, NULL);
2443                 if (!rc)
2444                         return 0;
2445         }
2446
2447         /*
2448          * We also permit NNP or nosuid transitions to bounded SIDs,
2449          * i.e. SIDs that are guaranteed to only be allowed a subset
2450          * of the permissions of the current SID.
2451          */
2452         rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2453                                          new_tsec->sid);
2454         if (!rc)
2455                 return 0;
2456
2457         /*
2458          * On failure, preserve the errno values for NNP vs nosuid.
2459          * NNP:  Operation not permitted for caller.
2460          * nosuid:  Permission denied to file.
2461          */
2462         if (nnp)
2463                 return -EPERM;
2464         return -EACCES;
2465 }
2466
2467 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2468 {
2469         const struct task_security_struct *old_tsec;
2470         struct task_security_struct *new_tsec;
2471         struct inode_security_struct *isec;
2472         struct common_audit_data ad;
2473         struct inode *inode = file_inode(bprm->file);
2474         int rc;
2475
2476         /* SELinux context only depends on initial program or script and not
2477          * the script interpreter */
2478         if (bprm->called_set_creds)
2479                 return 0;
2480
2481         old_tsec = current_security();
2482         new_tsec = bprm->cred->security;
2483         isec = inode_security(inode);
2484
2485         /* Default to the current task SID. */
2486         new_tsec->sid = old_tsec->sid;
2487         new_tsec->osid = old_tsec->sid;
2488
2489         /* Reset fs, key, and sock SIDs on execve. */
2490         new_tsec->create_sid = 0;
2491         new_tsec->keycreate_sid = 0;
2492         new_tsec->sockcreate_sid = 0;
2493
2494         if (old_tsec->exec_sid) {
2495                 new_tsec->sid = old_tsec->exec_sid;
2496                 /* Reset exec SID on execve. */
2497                 new_tsec->exec_sid = 0;
2498
2499                 /* Fail on NNP or nosuid if not an allowed transition. */
2500                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2501                 if (rc)
2502                         return rc;
2503         } else {
2504                 /* Check for a default transition on this program. */
2505                 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2506                                              isec->sid, SECCLASS_PROCESS, NULL,
2507                                              &new_tsec->sid);
2508                 if (rc)
2509                         return rc;
2510
2511                 /*
2512                  * Fallback to old SID on NNP or nosuid if not an allowed
2513                  * transition.
2514                  */
2515                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2516                 if (rc)
2517                         new_tsec->sid = old_tsec->sid;
2518         }
2519
2520         ad.type = LSM_AUDIT_DATA_FILE;
2521         ad.u.file = bprm->file;
2522
2523         if (new_tsec->sid == old_tsec->sid) {
2524                 rc = avc_has_perm(&selinux_state,
2525                                   old_tsec->sid, isec->sid,
2526                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2527                 if (rc)
2528                         return rc;
2529         } else {
2530                 /* Check permissions for the transition. */
2531                 rc = avc_has_perm(&selinux_state,
2532                                   old_tsec->sid, new_tsec->sid,
2533                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2534                 if (rc)
2535                         return rc;
2536
2537                 rc = avc_has_perm(&selinux_state,
2538                                   new_tsec->sid, isec->sid,
2539                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2540                 if (rc)
2541                         return rc;
2542
2543                 /* Check for shared state */
2544                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2545                         rc = avc_has_perm(&selinux_state,
2546                                           old_tsec->sid, new_tsec->sid,
2547                                           SECCLASS_PROCESS, PROCESS__SHARE,
2548                                           NULL);
2549                         if (rc)
2550                                 return -EPERM;
2551                 }
2552
2553                 /* Make sure that anyone attempting to ptrace over a task that
2554                  * changes its SID has the appropriate permit */
2555                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2556                         u32 ptsid = ptrace_parent_sid();
2557                         if (ptsid != 0) {
2558                                 rc = avc_has_perm(&selinux_state,
2559                                                   ptsid, new_tsec->sid,
2560                                                   SECCLASS_PROCESS,
2561                                                   PROCESS__PTRACE, NULL);
2562                                 if (rc)
2563                                         return -EPERM;
2564                         }
2565                 }
2566
2567                 /* Clear any possibly unsafe personality bits on exec: */
2568                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2569
2570                 /* Enable secure mode for SIDs transitions unless
2571                    the noatsecure permission is granted between
2572                    the two SIDs, i.e. ahp returns 0. */
2573                 rc = avc_has_perm(&selinux_state,
2574                                   old_tsec->sid, new_tsec->sid,
2575                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2576                                   NULL);
2577                 bprm->secureexec |= !!rc;
2578         }
2579
2580         return 0;
2581 }
2582
2583 static int match_file(const void *p, struct file *file, unsigned fd)
2584 {
2585         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2586 }
2587
2588 /* Derived from fs/exec.c:flush_old_files. */
2589 static inline void flush_unauthorized_files(const struct cred *cred,
2590                                             struct files_struct *files)
2591 {
2592         struct file *file, *devnull = NULL;
2593         struct tty_struct *tty;
2594         int drop_tty = 0;
2595         unsigned n;
2596
2597         tty = get_current_tty();
2598         if (tty) {
2599                 spin_lock(&tty->files_lock);
2600                 if (!list_empty(&tty->tty_files)) {
2601                         struct tty_file_private *file_priv;
2602
2603                         /* Revalidate access to controlling tty.
2604                            Use file_path_has_perm on the tty path directly
2605                            rather than using file_has_perm, as this particular
2606                            open file may belong to another process and we are
2607                            only interested in the inode-based check here. */
2608                         file_priv = list_first_entry(&tty->tty_files,
2609                                                 struct tty_file_private, list);
2610                         file = file_priv->file;
2611                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2612                                 drop_tty = 1;
2613                 }
2614                 spin_unlock(&tty->files_lock);
2615                 tty_kref_put(tty);
2616         }
2617         /* Reset controlling tty. */
2618         if (drop_tty)
2619                 no_tty();
2620
2621         /* Revalidate access to inherited open files. */
2622         n = iterate_fd(files, 0, match_file, cred);
2623         if (!n) /* none found? */
2624                 return;
2625
2626         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2627         if (IS_ERR(devnull))
2628                 devnull = NULL;
2629         /* replace all the matching ones with this */
2630         do {
2631                 replace_fd(n - 1, devnull, 0);
2632         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2633         if (devnull)
2634                 fput(devnull);
2635 }
2636
2637 /*
2638  * Prepare a process for imminent new credential changes due to exec
2639  */
2640 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2641 {
2642         struct task_security_struct *new_tsec;
2643         struct rlimit *rlim, *initrlim;
2644         int rc, i;
2645
2646         new_tsec = bprm->cred->security;
2647         if (new_tsec->sid == new_tsec->osid)
2648                 return;
2649
2650         /* Close files for which the new task SID is not authorized. */
2651         flush_unauthorized_files(bprm->cred, current->files);
2652
2653         /* Always clear parent death signal on SID transitions. */
2654         current->pdeath_signal = 0;
2655
2656         /* Check whether the new SID can inherit resource limits from the old
2657          * SID.  If not, reset all soft limits to the lower of the current
2658          * task's hard limit and the init task's soft limit.
2659          *
2660          * Note that the setting of hard limits (even to lower them) can be
2661          * controlled by the setrlimit check.  The inclusion of the init task's
2662          * soft limit into the computation is to avoid resetting soft limits
2663          * higher than the default soft limit for cases where the default is
2664          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2665          */
2666         rc = avc_has_perm(&selinux_state,
2667                           new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2668                           PROCESS__RLIMITINH, NULL);
2669         if (rc) {
2670                 /* protect against do_prlimit() */
2671                 task_lock(current);
2672                 for (i = 0; i < RLIM_NLIMITS; i++) {
2673                         rlim = current->signal->rlim + i;
2674                         initrlim = init_task.signal->rlim + i;
2675                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2676                 }
2677                 task_unlock(current);
2678                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2679                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2680         }
2681 }
2682
2683 /*
2684  * Clean up the process immediately after the installation of new credentials
2685  * due to exec
2686  */
2687 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2688 {
2689         const struct task_security_struct *tsec = current_security();
2690         struct itimerval itimer;
2691         u32 osid, sid;
2692         int rc, i;
2693
2694         osid = tsec->osid;
2695         sid = tsec->sid;
2696
2697         if (sid == osid)
2698                 return;
2699
2700         /* Check whether the new SID can inherit signal state from the old SID.
2701          * If not, clear itimers to avoid subsequent signal generation and
2702          * flush and unblock signals.
2703          *
2704          * This must occur _after_ the task SID has been updated so that any
2705          * kill done after the flush will be checked against the new SID.
2706          */
2707         rc = avc_has_perm(&selinux_state,
2708                           osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2709         if (rc) {
2710                 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2711                         memset(&itimer, 0, sizeof itimer);
2712                         for (i = 0; i < 3; i++)
2713                                 do_setitimer(i, &itimer, NULL);
2714                 }
2715                 spin_lock_irq(&current->sighand->siglock);
2716                 if (!fatal_signal_pending(current)) {
2717                         flush_sigqueue(&current->pending);
2718                         flush_sigqueue(&current->signal->shared_pending);
2719                         flush_signal_handlers(current, 1);
2720                         sigemptyset(&current->blocked);
2721                         recalc_sigpending();
2722                 }
2723                 spin_unlock_irq(&current->sighand->siglock);
2724         }
2725
2726         /* Wake up the parent if it is waiting so that it can recheck
2727          * wait permission to the new task SID. */
2728         read_lock(&tasklist_lock);
2729         __wake_up_parent(current, current->real_parent);
2730         read_unlock(&tasklist_lock);
2731 }
2732
2733 /* superblock security operations */
2734
2735 static int selinux_sb_alloc_security(struct super_block *sb)
2736 {
2737         return superblock_alloc_security(sb);
2738 }
2739
2740 static void selinux_sb_free_security(struct super_block *sb)
2741 {
2742         superblock_free_security(sb);
2743 }
2744
2745 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2746 {
2747         if (plen > olen)
2748                 return 0;
2749
2750         return !memcmp(prefix, option, plen);
2751 }
2752
2753 static inline int selinux_option(char *option, int len)
2754 {
2755         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2756                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2757                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2758                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2759                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2760 }
2761
2762 static inline void take_option(char **to, char *from, int *first, int len)
2763 {
2764         if (!*first) {
2765                 **to = ',';
2766                 *to += 1;
2767         } else
2768                 *first = 0;
2769         memcpy(*to, from, len);
2770         *to += len;
2771 }
2772
2773 static inline void take_selinux_option(char **to, char *from, int *first,
2774                                        int len)
2775 {
2776         int current_size = 0;
2777
2778         if (!*first) {
2779                 **to = '|';
2780                 *to += 1;
2781         } else
2782                 *first = 0;
2783
2784         while (current_size < len) {
2785                 if (*from != '"') {
2786                         **to = *from;
2787                         *to += 1;
2788                 }
2789                 from += 1;
2790                 current_size += 1;
2791         }
2792 }
2793
2794 static int selinux_sb_copy_data(char *orig, char *copy)
2795 {
2796         int fnosec, fsec, rc = 0;
2797         char *in_save, *in_curr, *in_end;
2798         char *sec_curr, *nosec_save, *nosec;
2799         int open_quote = 0;
2800
2801         in_curr = orig;
2802         sec_curr = copy;
2803
2804         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2805         if (!nosec) {
2806                 rc = -ENOMEM;
2807                 goto out;
2808         }
2809
2810         nosec_save = nosec;
2811         fnosec = fsec = 1;
2812         in_save = in_end = orig;
2813
2814         do {
2815                 if (*in_end == '"')
2816                         open_quote = !open_quote;
2817                 if ((*in_end == ',' && open_quote == 0) ||
2818                                 *in_end == '\0') {
2819                         int len = in_end - in_curr;
2820
2821                         if (selinux_option(in_curr, len))
2822                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2823                         else
2824                                 take_option(&nosec, in_curr, &fnosec, len);
2825
2826                         in_curr = in_end + 1;
2827                 }
2828         } while (*in_end++);
2829
2830         strcpy(in_save, nosec_save);
2831         free_page((unsigned long)nosec_save);
2832 out:
2833         return rc;
2834 }
2835
2836 static int selinux_sb_remount(struct super_block *sb, void *data)
2837 {
2838         int rc, i, *flags;
2839         struct security_mnt_opts opts;
2840         char *secdata, **mount_options;
2841         struct superblock_security_struct *sbsec = sb->s_security;
2842
2843         if (!(sbsec->flags & SE_SBINITIALIZED))
2844                 return 0;
2845
2846         if (!data)
2847                 return 0;
2848
2849         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2850                 return 0;
2851
2852         security_init_mnt_opts(&opts);
2853         secdata = alloc_secdata();
2854         if (!secdata)
2855                 return -ENOMEM;
2856         rc = selinux_sb_copy_data(data, secdata);
2857         if (rc)
2858                 goto out_free_secdata;
2859
2860         rc = selinux_parse_opts_str(secdata, &opts);
2861         if (rc)
2862                 goto out_free_secdata;
2863
2864         mount_options = opts.mnt_opts;
2865         flags = opts.mnt_opts_flags;
2866
2867         for (i = 0; i < opts.num_mnt_opts; i++) {
2868                 u32 sid;
2869
2870                 if (flags[i] == SBLABEL_MNT)
2871                         continue;
2872                 rc = security_context_str_to_sid(&selinux_state,
2873                                                  mount_options[i], &sid,
2874                                                  GFP_KERNEL);
2875                 if (rc) {
2876                         pr_warn("SELinux: security_context_str_to_sid"
2877                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2878                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2879                         goto out_free_opts;
2880                 }
2881                 rc = -EINVAL;
2882                 switch (flags[i]) {
2883                 case FSCONTEXT_MNT:
2884                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2885                                 goto out_bad_option;
2886                         break;
2887                 case CONTEXT_MNT:
2888                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2889                                 goto out_bad_option;
2890                         break;
2891                 case ROOTCONTEXT_MNT: {
2892                         struct inode_security_struct *root_isec;
2893                         root_isec = backing_inode_security(sb->s_root);
2894
2895                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2896                                 goto out_bad_option;
2897                         break;
2898                 }
2899                 case DEFCONTEXT_MNT:
2900                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2901                                 goto out_bad_option;
2902                         break;
2903                 default:
2904                         goto out_free_opts;
2905                 }
2906         }
2907
2908         rc = 0;
2909 out_free_opts:
2910         security_free_mnt_opts(&opts);
2911 out_free_secdata:
2912         free_secdata(secdata);
2913         return rc;
2914 out_bad_option:
2915         pr_warn("SELinux: unable to change security options "
2916                "during remount (dev %s, type=%s)\n", sb->s_id,
2917                sb->s_type->name);
2918         goto out_free_opts;
2919 }
2920
2921 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2922 {
2923         const struct cred *cred = current_cred();
2924         struct common_audit_data ad;
2925         int rc;
2926
2927         rc = superblock_doinit(sb, data);
2928         if (rc)
2929                 return rc;
2930
2931         /* Allow all mounts performed by the kernel */
2932         if (flags & MS_KERNMOUNT)
2933                 return 0;
2934
2935         ad.type = LSM_AUDIT_DATA_DENTRY;
2936         ad.u.dentry = sb->s_root;
2937         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2938 }
2939
2940 static int selinux_sb_statfs(struct dentry *dentry)
2941 {
2942         const struct cred *cred = current_cred();
2943         struct common_audit_data ad;
2944
2945         ad.type = LSM_AUDIT_DATA_DENTRY;
2946         ad.u.dentry = dentry->d_sb->s_root;
2947         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2948 }
2949
2950 static int selinux_mount(const char *dev_name,
2951                          const struct path *path,
2952                          const char *type,
2953                          unsigned long flags,
2954                          void *data)
2955 {
2956         const struct cred *cred = current_cred();
2957
2958         if (flags & MS_REMOUNT)
2959                 return superblock_has_perm(cred, path->dentry->d_sb,
2960                                            FILESYSTEM__REMOUNT, NULL);
2961         else
2962                 return path_has_perm(cred, path, FILE__MOUNTON);
2963 }
2964
2965 static int selinux_umount(struct vfsmount *mnt, int flags)
2966 {
2967         const struct cred *cred = current_cred();
2968
2969         return superblock_has_perm(cred, mnt->mnt_sb,
2970                                    FILESYSTEM__UNMOUNT, NULL);
2971 }
2972
2973 /* inode security operations */
2974
2975 static int selinux_inode_alloc_security(struct inode *inode)
2976 {
2977         return inode_alloc_security(inode);
2978 }
2979
2980 static void selinux_inode_free_security(struct inode *inode)
2981 {
2982         inode_free_security(inode);
2983 }
2984
2985 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2986                                         const struct qstr *name, void **ctx,
2987                                         u32 *ctxlen)
2988 {
2989         u32 newsid;
2990         int rc;
2991
2992         rc = selinux_determine_inode_label(current_security(),
2993                                            d_inode(dentry->d_parent), name,
2994                                            inode_mode_to_security_class(mode),
2995                                            &newsid);
2996         if (rc)
2997                 return rc;
2998
2999         return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
3000                                        ctxlen);
3001 }
3002
3003 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
3004                                           struct qstr *name,
3005                                           const struct cred *old,
3006                                           struct cred *new)
3007 {
3008         u32 newsid;
3009         int rc;
3010         struct task_security_struct *tsec;
3011
3012         rc = selinux_determine_inode_label(old->security,
3013                                            d_inode(dentry->d_parent), name,
3014                                            inode_mode_to_security_class(mode),
3015                                            &newsid);
3016         if (rc)
3017                 return rc;
3018
3019         tsec = new->security;
3020         tsec->create_sid = newsid;
3021         return 0;
3022 }
3023
3024 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
3025                                        const struct qstr *qstr,
3026                                        const char **name,
3027                                        void **value, size_t *len)
3028 {
3029         const struct task_security_struct *tsec = current_security();
3030         struct superblock_security_struct *sbsec;
3031         u32 newsid, clen;
3032         int rc;
3033         char *context;
3034
3035         sbsec = dir->i_sb->s_security;
3036
3037         newsid = tsec->create_sid;
3038
3039         rc = selinux_determine_inode_label(current_security(),
3040                 dir, qstr,
3041                 inode_mode_to_security_class(inode->i_mode),
3042                 &newsid);
3043         if (rc)
3044                 return rc;
3045
3046         /* Possibly defer initialization to selinux_complete_init. */
3047         if (sbsec->flags & SE_SBINITIALIZED) {
3048                 struct inode_security_struct *isec = inode->i_security;
3049                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3050                 isec->sid = newsid;
3051                 isec->initialized = LABEL_INITIALIZED;
3052         }
3053
3054         if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT))
3055                 return -EOPNOTSUPP;
3056
3057         if (name)
3058                 *name = XATTR_SELINUX_SUFFIX;
3059
3060         if (value && len) {
3061                 rc = security_sid_to_context_force(&selinux_state, newsid,
3062                                                    &context, &clen);
3063                 if (rc)
3064                         return rc;
3065                 *value = context;
3066                 *len = clen;
3067         }
3068
3069         return 0;
3070 }
3071
3072 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3073 {
3074         return may_create(dir, dentry, SECCLASS_FILE);
3075 }
3076
3077 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3078 {
3079         return may_link(dir, old_dentry, MAY_LINK);
3080 }
3081
3082 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3083 {
3084         return may_link(dir, dentry, MAY_UNLINK);
3085 }
3086
3087 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3088 {
3089         return may_create(dir, dentry, SECCLASS_LNK_FILE);
3090 }
3091
3092 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3093 {
3094         return may_create(dir, dentry, SECCLASS_DIR);
3095 }
3096
3097 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3098 {
3099         return may_link(dir, dentry, MAY_RMDIR);
3100 }
3101
3102 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3103 {
3104         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3105 }
3106
3107 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3108                                 struct inode *new_inode, struct dentry *new_dentry)
3109 {
3110         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3111 }
3112
3113 static int selinux_inode_readlink(struct dentry *dentry)
3114 {
3115         const struct cred *cred = current_cred();
3116
3117         return dentry_has_perm(cred, dentry, FILE__READ);
3118 }
3119
3120 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3121                                      bool rcu)
3122 {
3123         const struct cred *cred = current_cred();
3124         struct common_audit_data ad;
3125         struct inode_security_struct *isec;
3126         u32 sid;
3127
3128         validate_creds(cred);
3129
3130         ad.type = LSM_AUDIT_DATA_DENTRY;
3131         ad.u.dentry = dentry;
3132         sid = cred_sid(cred);
3133         isec = inode_security_rcu(inode, rcu);
3134         if (IS_ERR(isec))
3135                 return PTR_ERR(isec);
3136
3137         return avc_has_perm_flags(&selinux_state,
3138                                   sid, isec->sid, isec->sclass, FILE__READ, &ad,
3139                                   rcu ? MAY_NOT_BLOCK : 0);
3140 }
3141
3142 static noinline int audit_inode_permission(struct inode *inode,
3143                                            u32 perms, u32 audited, u32 denied,
3144                                            int result,
3145                                            unsigned flags)
3146 {
3147         struct common_audit_data ad;
3148         struct inode_security_struct *isec = inode->i_security;
3149         int rc;
3150
3151         ad.type = LSM_AUDIT_DATA_INODE;
3152         ad.u.inode = inode;
3153
3154         rc = slow_avc_audit(&selinux_state,
3155                             current_sid(), isec->sid, isec->sclass, perms,
3156                             audited, denied, result, &ad, flags);
3157         if (rc)
3158                 return rc;
3159         return 0;
3160 }
3161
3162 static int selinux_inode_permission(struct inode *inode, int mask)
3163 {
3164         const struct cred *cred = current_cred();
3165         u32 perms;
3166         bool from_access;
3167         unsigned flags = mask & MAY_NOT_BLOCK;
3168         struct inode_security_struct *isec;
3169         u32 sid;
3170         struct av_decision avd;
3171         int rc, rc2;
3172         u32 audited, denied;
3173
3174         from_access = mask & MAY_ACCESS;
3175         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3176
3177         /* No permission to check.  Existence test. */
3178         if (!mask)
3179                 return 0;
3180
3181         validate_creds(cred);
3182
3183         if (unlikely(IS_PRIVATE(inode)))
3184                 return 0;
3185
3186         perms = file_mask_to_av(inode->i_mode, mask);
3187
3188         sid = cred_sid(cred);
3189         isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3190         if (IS_ERR(isec))
3191                 return PTR_ERR(isec);
3192
3193         rc = avc_has_perm_noaudit(&selinux_state,
3194                                   sid, isec->sid, isec->sclass, perms, 0, &avd);
3195         audited = avc_audit_required(perms, &avd, rc,
3196                                      from_access ? FILE__AUDIT_ACCESS : 0,
3197                                      &denied);
3198         if (likely(!audited))
3199                 return rc;
3200
3201         rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3202         if (rc2)
3203                 return rc2;
3204         return rc;
3205 }
3206
3207 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3208 {
3209         const struct cred *cred = current_cred();
3210         struct inode *inode = d_backing_inode(dentry);
3211         unsigned int ia_valid = iattr->ia_valid;
3212         __u32 av = FILE__WRITE;
3213
3214         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3215         if (ia_valid & ATTR_FORCE) {
3216                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3217                               ATTR_FORCE);
3218                 if (!ia_valid)
3219                         return 0;
3220         }
3221
3222         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3223                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3224                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3225
3226         if (selinux_policycap_openperm() &&
3227             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3228             (ia_valid & ATTR_SIZE) &&
3229             !(ia_valid & ATTR_FILE))
3230                 av |= FILE__OPEN;
3231
3232         return dentry_has_perm(cred, dentry, av);
3233 }
3234
3235 static int selinux_inode_getattr(const struct path *path)
3236 {
3237         return path_has_perm(current_cred(), path, FILE__GETATTR);
3238 }
3239
3240 static bool has_cap_mac_admin(bool audit)
3241 {
3242         const struct cred *cred = current_cred();
3243         int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT;
3244
3245         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit))
3246                 return false;
3247         if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true))
3248                 return false;
3249         return true;
3250 }
3251
3252 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3253                                   const void *value, size_t size, int flags)
3254 {
3255         struct inode *inode = d_backing_inode(dentry);
3256         struct inode_security_struct *isec;
3257         struct superblock_security_struct *sbsec;
3258         struct common_audit_data ad;
3259         u32 newsid, sid = current_sid();
3260         int rc = 0;
3261
3262         if (strcmp(name, XATTR_NAME_SELINUX)) {
3263                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3264                 if (rc)
3265                         return rc;
3266
3267                 /* Not an attribute we recognize, so just check the
3268                    ordinary setattr permission. */
3269                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3270         }
3271
3272         sbsec = inode->i_sb->s_security;
3273         if (!(sbsec->flags & SBLABEL_MNT))
3274                 return -EOPNOTSUPP;
3275
3276         if (!inode_owner_or_capable(inode))
3277                 return -EPERM;
3278
3279         ad.type = LSM_AUDIT_DATA_DENTRY;
3280         ad.u.dentry = dentry;
3281
3282         isec = backing_inode_security(dentry);
3283         rc = avc_has_perm(&selinux_state,
3284                           sid, isec->sid, isec->sclass,
3285                           FILE__RELABELFROM, &ad);
3286         if (rc)
3287                 return rc;
3288
3289         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3290                                      GFP_KERNEL);
3291         if (rc == -EINVAL) {
3292                 if (!has_cap_mac_admin(true)) {
3293                         struct audit_buffer *ab;
3294                         size_t audit_size;
3295
3296                         /* We strip a nul only if it is at the end, otherwise the
3297                          * context contains a nul and we should audit that */
3298                         if (value) {
3299                                 const char *str = value;
3300
3301                                 if (str[size - 1] == '\0')
3302                                         audit_size = size - 1;
3303                                 else
3304                                         audit_size = size;
3305                         } else {
3306                                 audit_size = 0;
3307                         }
3308                         ab = audit_log_start(audit_context(),
3309                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3310                         audit_log_format(ab, "op=setxattr invalid_context=");
3311                         audit_log_n_untrustedstring(ab, value, audit_size);
3312                         audit_log_end(ab);
3313
3314                         return rc;
3315                 }
3316                 rc = security_context_to_sid_force(&selinux_state, value,
3317                                                    size, &newsid);
3318         }
3319         if (rc)
3320                 return rc;
3321
3322         rc = avc_has_perm(&selinux_state,
3323                           sid, newsid, isec->sclass,
3324                           FILE__RELABELTO, &ad);
3325         if (rc)
3326                 return rc;
3327
3328         rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3329                                           sid, isec->sclass);
3330         if (rc)
3331                 return rc;
3332
3333         return avc_has_perm(&selinux_state,
3334                             newsid,
3335                             sbsec->sid,
3336                             SECCLASS_FILESYSTEM,
3337                             FILESYSTEM__ASSOCIATE,
3338                             &ad);
3339 }
3340
3341 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3342                                         const void *value, size_t size,
3343                                         int flags)
3344 {
3345         struct inode *inode = d_backing_inode(dentry);
3346         struct inode_security_struct *isec;
3347         u32 newsid;
3348         int rc;
3349
3350         if (strcmp(name, XATTR_NAME_SELINUX)) {
3351                 /* Not an attribute we recognize, so nothing to do. */
3352                 return;
3353         }
3354
3355         rc = security_context_to_sid_force(&selinux_state, value, size,
3356                                            &newsid);
3357         if (rc) {
3358                 pr_err("SELinux:  unable to map context to SID"
3359                        "for (%s, %lu), rc=%d\n",
3360                        inode->i_sb->s_id, inode->i_ino, -rc);
3361                 return;
3362         }
3363
3364         isec = backing_inode_security(dentry);
3365         spin_lock(&isec->lock);
3366         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3367         isec->sid = newsid;
3368         isec->initialized = LABEL_INITIALIZED;
3369         spin_unlock(&isec->lock);
3370
3371         return;
3372 }
3373
3374 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3375 {
3376         const struct cred *cred = current_cred();
3377
3378         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3379 }
3380
3381 static int selinux_inode_listxattr(struct dentry *dentry)
3382 {
3383         const struct cred *cred = current_cred();
3384
3385         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3386 }
3387
3388 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3389 {
3390         if (strcmp(name, XATTR_NAME_SELINUX)) {
3391                 int rc = cap_inode_removexattr(dentry, name);
3392                 if (rc)
3393                         return rc;
3394
3395                 /* Not an attribute we recognize, so just check the
3396                    ordinary setattr permission. */
3397                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3398         }
3399
3400         /* No one is allowed to remove a SELinux security label.
3401            You can change the label, but all data must be labeled. */
3402         return -EACCES;
3403 }
3404
3405 /*
3406  * Copy the inode security context value to the user.
3407  *
3408  * Permission check is handled by selinux_inode_getxattr hook.
3409  */
3410 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3411 {
3412         u32 size;
3413         int error;
3414         char *context = NULL;
3415         struct inode_security_struct *isec;
3416
3417         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3418                 return -EOPNOTSUPP;
3419
3420         /*
3421          * If the caller has CAP_MAC_ADMIN, then get the raw context
3422          * value even if it is not defined by current policy; otherwise,
3423          * use the in-core value under current policy.
3424          * Use the non-auditing forms of the permission checks since
3425          * getxattr may be called by unprivileged processes commonly
3426          * and lack of permission just means that we fall back to the
3427          * in-core context value, not a denial.
3428          */
3429         isec = inode_security(inode);
3430         if (has_cap_mac_admin(false))
3431                 error = security_sid_to_context_force(&selinux_state,
3432                                                       isec->sid, &context,
3433                                                       &size);
3434         else
3435                 error = security_sid_to_context(&selinux_state, isec->sid,
3436                                                 &context, &size);
3437         if (error)
3438                 return error;
3439         error = size;
3440         if (alloc) {
3441                 *buffer = context;
3442                 goto out_nofree;
3443         }
3444         kfree(context);
3445 out_nofree:
3446         return error;
3447 }
3448
3449 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3450                                      const void *value, size_t size, int flags)
3451 {
3452         struct inode_security_struct *isec = inode_security_novalidate(inode);
3453         u32 newsid;
3454         int rc;
3455
3456         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3457                 return -EOPNOTSUPP;
3458
3459         if (!value || !size)
3460                 return -EACCES;
3461
3462         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3463                                      GFP_KERNEL);
3464         if (rc)
3465                 return rc;
3466
3467         spin_lock(&isec->lock);
3468         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3469         isec->sid = newsid;
3470         isec->initialized = LABEL_INITIALIZED;
3471         spin_unlock(&isec->lock);
3472         return 0;
3473 }
3474
3475 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3476 {
3477         const int len = sizeof(XATTR_NAME_SELINUX);
3478         if (buffer && len <= buffer_size)
3479                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3480         return len;
3481 }
3482
3483 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3484 {
3485         struct inode_security_struct *isec = inode_security_novalidate(inode);
3486         *secid = isec->sid;
3487 }
3488
3489 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3490 {
3491         u32 sid;
3492         struct task_security_struct *tsec;
3493         struct cred *new_creds = *new;
3494
3495         if (new_creds == NULL) {
3496                 new_creds = prepare_creds();
3497                 if (!new_creds)
3498                         return -ENOMEM;
3499         }
3500
3501         tsec = new_creds->security;
3502         /* Get label from overlay inode and set it in create_sid */
3503         selinux_inode_getsecid(d_inode(src), &sid);
3504         tsec->create_sid = sid;
3505         *new = new_creds;
3506         return 0;
3507 }
3508
3509 static int selinux_inode_copy_up_xattr(const char *name)
3510 {
3511         /* The copy_up hook above sets the initial context on an inode, but we
3512          * don't then want to overwrite it by blindly copying all the lower
3513          * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3514          */
3515         if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3516                 return 1; /* Discard */
3517         /*
3518          * Any other attribute apart from SELINUX is not claimed, supported
3519          * by selinux.
3520          */
3521         return -EOPNOTSUPP;
3522 }
3523
3524 /* file security operations */
3525
3526 static int selinux_revalidate_file_permission(struct file *file, int mask)
3527 {
3528         const struct cred *cred = current_cred();
3529         struct inode *inode = file_inode(file);
3530
3531         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3532         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3533                 mask |= MAY_APPEND;
3534
3535         return file_has_perm(cred, file,
3536                              file_mask_to_av(inode->i_mode, mask));
3537 }
3538
3539 static int selinux_file_permission(struct file *file, int mask)
3540 {
3541         struct inode *inode = file_inode(file);
3542         struct file_security_struct *fsec = file->f_security;
3543         struct inode_security_struct *isec;
3544         u32 sid = current_sid();
3545
3546         if (!mask)
3547                 /* No permission to check.  Existence test. */
3548                 return 0;
3549
3550         isec = inode_security(inode);
3551         if (sid == fsec->sid && fsec->isid == isec->sid &&
3552             fsec->pseqno == avc_policy_seqno(&selinux_state))
3553                 /* No change since file_open check. */
3554                 return 0;
3555
3556         return selinux_revalidate_file_permission(file, mask);
3557 }
3558
3559 static int selinux_file_alloc_security(struct file *file)
3560 {
3561         return file_alloc_security(file);
3562 }
3563
3564 static void selinux_file_free_security(struct file *file)
3565 {
3566         file_free_security(file);
3567 }
3568
3569 /*
3570  * Check whether a task has the ioctl permission and cmd
3571  * operation to an inode.
3572  */
3573 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3574                 u32 requested, u16 cmd)
3575 {
3576         struct common_audit_data ad;
3577         struct file_security_struct *fsec = file->f_security;
3578         struct inode *inode = file_inode(file);
3579         struct inode_security_struct *isec;
3580         struct lsm_ioctlop_audit ioctl;
3581         u32 ssid = cred_sid(cred);
3582         int rc;
3583         u8 driver = cmd >> 8;
3584         u8 xperm = cmd & 0xff;
3585
3586         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3587         ad.u.op = &ioctl;
3588         ad.u.op->cmd = cmd;
3589         ad.u.op->path = file->f_path;
3590
3591         if (ssid != fsec->sid) {
3592                 rc = avc_has_perm(&selinux_state,
3593                                   ssid, fsec->sid,
3594                                 SECCLASS_FD,
3595                                 FD__USE,
3596                                 &ad);
3597                 if (rc)
3598                         goto out;
3599         }
3600
3601         if (unlikely(IS_PRIVATE(inode)))
3602                 return 0;
3603
3604         isec = inode_security(inode);
3605         rc = avc_has_extended_perms(&selinux_state,
3606                                     ssid, isec->sid, isec->sclass,
3607                                     requested, driver, xperm, &ad);
3608 out:
3609         return rc;
3610 }
3611
3612 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3613                               unsigned long arg)
3614 {
3615         const struct cred *cred = current_cred();
3616         int error = 0;
3617
3618         switch (cmd) {
3619         case FIONREAD:
3620         /* fall through */
3621         case FIBMAP:
3622         /* fall through */
3623         case FIGETBSZ:
3624         /* fall through */
3625         case FS_IOC_GETFLAGS:
3626         /* fall through */
3627         case FS_IOC_GETVERSION:
3628                 error = file_has_perm(cred, file, FILE__GETATTR);
3629                 break;
3630
3631         case FS_IOC_SETFLAGS:
3632         /* fall through */
3633         case FS_IOC_SETVERSION:
3634                 error = file_has_perm(cred, file, FILE__SETATTR);
3635                 break;
3636
3637         /* sys_ioctl() checks */
3638         case FIONBIO:
3639         /* fall through */
3640         case FIOASYNC:
3641                 error = file_has_perm(cred, file, 0);
3642                 break;
3643
3644         case KDSKBENT:
3645         case KDSKBSENT:
3646                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3647                                             SECURITY_CAP_AUDIT, true);
3648                 break;
3649
3650         /* default case assumes that the command will go
3651          * to the file's ioctl() function.
3652          */
3653         default:
3654                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3655         }
3656         return error;
3657 }
3658
3659 static int default_noexec;
3660
3661 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3662 {
3663         const struct cred *cred = current_cred();
3664         u32 sid = cred_sid(cred);
3665         int rc = 0;
3666
3667         if (default_noexec &&
3668             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3669                                    (!shared && (prot & PROT_WRITE)))) {
3670                 /*
3671                  * We are making executable an anonymous mapping or a
3672                  * private file mapping that will also be writable.
3673                  * This has an additional check.
3674                  */
3675                 rc = avc_has_perm(&selinux_state,
3676                                   sid, sid, SECCLASS_PROCESS,
3677                                   PROCESS__EXECMEM, NULL);
3678                 if (rc)
3679                         goto error;
3680         }
3681
3682         if (file) {
3683                 /* read access is always possible with a mapping */
3684                 u32 av = FILE__READ;
3685
3686                 /* write access only matters if the mapping is shared */
3687                 if (shared && (prot & PROT_WRITE))
3688                         av |= FILE__WRITE;
3689
3690                 if (prot & PROT_EXEC)
3691                         av |= FILE__EXECUTE;
3692
3693                 return file_has_perm(cred, file, av);
3694         }
3695
3696 error:
3697         return rc;
3698 }
3699
3700 static int selinux_mmap_addr(unsigned long addr)
3701 {
3702         int rc = 0;
3703
3704         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3705                 u32 sid = current_sid();
3706                 rc = avc_has_perm(&selinux_state,
3707                                   sid, sid, SECCLASS_MEMPROTECT,
3708                                   MEMPROTECT__MMAP_ZERO, NULL);
3709         }
3710
3711         return rc;
3712 }
3713
3714 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3715                              unsigned long prot, unsigned long flags)
3716 {
3717         struct common_audit_data ad;
3718         int rc;
3719
3720         if (file) {
3721                 ad.type = LSM_AUDIT_DATA_FILE;
3722                 ad.u.file = file;
3723                 rc = inode_has_perm(current_cred(), file_inode(file),
3724                                     FILE__MAP, &ad);
3725                 if (rc)
3726                         return rc;
3727         }
3728
3729         if (selinux_state.checkreqprot)
3730                 prot = reqprot;
3731
3732         return file_map_prot_check(file, prot,
3733                                    (flags & MAP_TYPE) == MAP_SHARED);
3734 }
3735
3736 static int selinux_file_mprotect(struct vm_area_struct *vma,
3737                                  unsigned long reqprot,
3738                                  unsigned long prot)
3739 {
3740         const struct cred *cred = current_cred();
3741         u32 sid = cred_sid(cred);
3742
3743         if (selinux_state.checkreqprot)
3744                 prot = reqprot;
3745
3746         if (default_noexec &&
3747             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3748                 int rc = 0;
3749                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3750                     vma->vm_end <= vma->vm_mm->brk) {
3751                         rc = avc_has_perm(&selinux_state,
3752                                           sid, sid, SECCLASS_PROCESS,
3753                                           PROCESS__EXECHEAP, NULL);
3754                 } else if (!vma->vm_file &&
3755                            ((vma->vm_start <= vma->vm_mm->start_stack &&
3756                              vma->vm_end >= vma->vm_mm->start_stack) ||
3757                             vma_is_stack_for_current(vma))) {
3758                         rc = avc_has_perm(&selinux_state,
3759                                           sid, sid, SECCLASS_PROCESS,
3760                                           PROCESS__EXECSTACK, NULL);
3761                 } else if (vma->vm_file && vma->anon_vma) {
3762                         /*
3763                          * We are making executable a file mapping that has
3764                          * had some COW done. Since pages might have been
3765                          * written, check ability to execute the possibly
3766                          * modified content.  This typically should only
3767                          * occur for text relocations.
3768                          */
3769                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3770                 }
3771                 if (rc)
3772                         return rc;
3773         }
3774
3775         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3776 }
3777
3778 static int selinux_file_lock(struct file *file, unsigned int cmd)
3779 {
3780         const struct cred *cred = current_cred();
3781
3782         return file_has_perm(cred, file, FILE__LOCK);
3783 }
3784
3785 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3786                               unsigned long arg)
3787 {
3788         const struct cred *cred = current_cred();
3789         int err = 0;
3790
3791         switch (cmd) {
3792         case F_SETFL:
3793                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3794                         err = file_has_perm(cred, file, FILE__WRITE);
3795                         break;
3796                 }
3797                 /* fall through */
3798         case F_SETOWN:
3799         case F_SETSIG:
3800         case F_GETFL:
3801         case F_GETOWN:
3802         case F_GETSIG:
3803         case F_GETOWNER_UIDS:
3804                 /* Just check FD__USE permission */
3805                 err = file_has_perm(cred, file, 0);
3806                 break;
3807         case F_GETLK:
3808         case F_SETLK:
3809         case F_SETLKW:
3810         case F_OFD_GETLK:
3811         case F_OFD_SETLK:
3812         case F_OFD_SETLKW:
3813 #if BITS_PER_LONG == 32
3814         case F_GETLK64:
3815         case F_SETLK64:
3816         case F_SETLKW64:
3817 #endif
3818                 err = file_has_perm(cred, file, FILE__LOCK);
3819                 break;
3820         }
3821
3822         return err;
3823 }
3824
3825 static void selinux_file_set_fowner(struct file *file)
3826 {
3827         struct file_security_struct *fsec;
3828
3829         fsec = file->f_security;
3830         fsec->fown_sid = current_sid();
3831 }
3832
3833 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3834                                        struct fown_struct *fown, int signum)
3835 {
3836         struct file *file;
3837         u32 sid = task_sid(tsk);
3838         u32 perm;
3839         struct file_security_struct *fsec;
3840
3841         /* struct fown_struct is never outside the context of a struct file */
3842         file = container_of(fown, struct file, f_owner);
3843
3844         fsec = file->f_security;
3845
3846         if (!signum)
3847                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3848         else
3849                 perm = signal_to_av(signum);
3850
3851         return avc_has_perm(&selinux_state,
3852                             fsec->fown_sid, sid,
3853                             SECCLASS_PROCESS, perm, NULL);
3854 }
3855
3856 static int selinux_file_receive(struct file *file)
3857 {
3858         const struct cred *cred = current_cred();
3859
3860         return file_has_perm(cred, file, file_to_av(file));
3861 }
3862
3863 static int selinux_file_open(struct file *file)
3864 {
3865         struct file_security_struct *fsec;
3866         struct inode_security_struct *isec;
3867
3868         fsec = file->f_security;
3869         isec = inode_security(file_inode(file));
3870         /*
3871          * Save inode label and policy sequence number
3872          * at open-time so that selinux_file_permission
3873          * can determine whether revalidation is necessary.
3874          * Task label is already saved in the file security
3875          * struct as its SID.
3876          */
3877         fsec->isid = isec->sid;
3878         fsec->pseqno = avc_policy_seqno(&selinux_state);
3879         /*
3880          * Since the inode label or policy seqno may have changed
3881          * between the selinux_inode_permission check and the saving
3882          * of state above, recheck that access is still permitted.
3883          * Otherwise, access might never be revalidated against the
3884          * new inode label or new policy.
3885          * This check is not redundant - do not remove.
3886          */
3887         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3888 }
3889
3890 /* task security operations */
3891
3892 static int selinux_task_alloc(struct task_struct *task,
3893                               unsigned long clone_flags)
3894 {
3895         u32 sid = current_sid();
3896
3897         return avc_has_perm(&selinux_state,
3898                             sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3899 }
3900
3901 /*
3902  * allocate the SELinux part of blank credentials
3903  */
3904 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3905 {
3906         struct task_security_struct *tsec;
3907
3908         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3909         if (!tsec)
3910                 return -ENOMEM;
3911
3912         cred->security = tsec;
3913         return 0;
3914 }
3915
3916 /*
3917  * detach and free the LSM part of a set of credentials
3918  */
3919 static void selinux_cred_free(struct cred *cred)
3920 {
3921         struct task_security_struct *tsec = cred->security;
3922
3923         /*
3924          * cred->security == NULL if security_cred_alloc_blank() or
3925          * security_prepare_creds() returned an error.
3926          */
3927         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3928         cred->security = (void *) 0x7UL;
3929         kfree(tsec);
3930 }
3931
3932 /*
3933  * prepare a new set of credentials for modification
3934  */
3935 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3936                                 gfp_t gfp)
3937 {
3938         const struct task_security_struct *old_tsec;
3939         struct task_security_struct *tsec;
3940
3941         old_tsec = old->security;
3942
3943         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3944         if (!tsec)
3945                 return -ENOMEM;
3946
3947         new->security = tsec;
3948         return 0;
3949 }
3950
3951 /*
3952  * transfer the SELinux data to a blank set of creds
3953  */
3954 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3955 {
3956         const struct task_security_struct *old_tsec = old->security;
3957         struct task_security_struct *tsec = new->security;
3958
3959         *tsec = *old_tsec;
3960 }
3961
3962 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3963 {
3964         *secid = cred_sid(c);
3965 }
3966
3967 /*
3968  * set the security data for a kernel service
3969  * - all the creation contexts are set to unlabelled
3970  */
3971 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3972 {
3973         struct task_security_struct *tsec = new->security;
3974         u32 sid = current_sid();
3975         int ret;
3976
3977         ret = avc_has_perm(&selinux_state,
3978                            sid, secid,
3979                            SECCLASS_KERNEL_SERVICE,
3980                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3981                            NULL);
3982         if (ret == 0) {
3983                 tsec->sid = secid;
3984                 tsec->create_sid = 0;
3985                 tsec->keycreate_sid = 0;
3986                 tsec->sockcreate_sid = 0;
3987         }
3988         return ret;
3989 }
3990
3991 /*
3992  * set the file creation context in a security record to the same as the
3993  * objective context of the specified inode
3994  */
3995 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3996 {
3997         struct inode_security_struct *isec = inode_security(inode);
3998         struct task_security_struct *tsec = new->security;
3999         u32 sid = current_sid();
4000         int ret;
4001
4002         ret = avc_has_perm(&selinux_state,
4003                            sid, isec->sid,
4004                            SECCLASS_KERNEL_SERVICE,
4005                            KERNEL_SERVICE__CREATE_FILES_AS,
4006                            NULL);
4007
4008         if (ret == 0)
4009                 tsec->create_sid = isec->sid;
4010         return ret;
4011 }
4012
4013 static int selinux_kernel_module_request(char *kmod_name)
4014 {
4015         struct common_audit_data ad;
4016
4017         ad.type = LSM_AUDIT_DATA_KMOD;
4018         ad.u.kmod_name = kmod_name;
4019
4020         return avc_has_perm(&selinux_state,
4021                             current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4022                             SYSTEM__MODULE_REQUEST, &ad);
4023 }
4024
4025 static int selinux_kernel_module_from_file(struct file *file)
4026 {
4027         struct common_audit_data ad;
4028         struct inode_security_struct *isec;
4029         struct file_security_struct *fsec;
4030         u32 sid = current_sid();
4031         int rc;
4032
4033         /* init_module */
4034         if (file == NULL)
4035                 return avc_has_perm(&selinux_state,
4036                                     sid, sid, SECCLASS_SYSTEM,
4037                                         SYSTEM__MODULE_LOAD, NULL);
4038
4039         /* finit_module */
4040
4041         ad.type = LSM_AUDIT_DATA_FILE;
4042         ad.u.file = file;
4043
4044         fsec = file->f_security;
4045         if (sid != fsec->sid) {
4046                 rc = avc_has_perm(&selinux_state,
4047                                   sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4048                 if (rc)
4049                         return rc;
4050         }
4051
4052         isec = inode_security(file_inode(file));
4053         return avc_has_perm(&selinux_state,
4054                             sid, isec->sid, SECCLASS_SYSTEM,
4055                                 SYSTEM__MODULE_LOAD, &ad);
4056 }
4057
4058 static int selinux_kernel_read_file(struct file *file,
4059                                     enum kernel_read_file_id id)
4060 {
4061         int rc = 0;
4062
4063         switch (id) {
4064         case READING_MODULE:
4065                 rc = selinux_kernel_module_from_file(file);
4066                 break;
4067         default:
4068                 break;
4069         }
4070
4071         return rc;
4072 }
4073
4074 static int selinux_kernel_load_data(enum kernel_load_data_id id)
4075 {
4076         int rc = 0;
4077
4078         switch (id) {
4079         case LOADING_MODULE:
4080                 rc = selinux_kernel_module_from_file(NULL);
4081         default:
4082                 break;
4083         }
4084
4085         return rc;
4086 }
4087
4088 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4089 {
4090         return avc_has_perm(&selinux_state,
4091                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4092                             PROCESS__SETPGID, NULL);
4093 }
4094
4095 static int selinux_task_getpgid(struct task_struct *p)
4096 {
4097         return avc_has_perm(&selinux_state,
4098                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4099                             PROCESS__GETPGID, NULL);
4100 }
4101
4102 static int selinux_task_getsid(struct task_struct *p)
4103 {
4104         return avc_has_perm(&selinux_state,
4105                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4106                             PROCESS__GETSESSION, NULL);
4107 }
4108
4109 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4110 {
4111         *secid = task_sid(p);
4112 }
4113
4114 static int selinux_task_setnice(struct task_struct *p, int nice)
4115 {
4116         return avc_has_perm(&selinux_state,
4117                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4118                             PROCESS__SETSCHED, NULL);
4119 }
4120
4121 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4122 {
4123         return avc_has_perm(&selinux_state,
4124                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4125                             PROCESS__SETSCHED, NULL);
4126 }
4127
4128 static int selinux_task_getioprio(struct task_struct *p)
4129 {
4130         return avc_has_perm(&selinux_state,
4131                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4132                             PROCESS__GETSCHED, NULL);
4133 }
4134
4135 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4136                                 unsigned int flags)
4137 {
4138         u32 av = 0;
4139
4140         if (!flags)
4141                 return 0;
4142         if (flags & LSM_PRLIMIT_WRITE)
4143                 av |= PROCESS__SETRLIMIT;
4144         if (flags & LSM_PRLIMIT_READ)
4145                 av |= PROCESS__GETRLIMIT;
4146         return avc_has_perm(&selinux_state,
4147                             cred_sid(cred), cred_sid(tcred),
4148                             SECCLASS_PROCESS, av, NULL);
4149 }
4150
4151 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4152                 struct rlimit *new_rlim)
4153 {
4154         struct rlimit *old_rlim = p->signal->rlim + resource;
4155
4156         /* Control the ability to change the hard limit (whether
4157            lowering or raising it), so that the hard limit can
4158            later be used as a safe reset point for the soft limit
4159            upon context transitions.  See selinux_bprm_committing_creds. */
4160         if (old_rlim->rlim_max != new_rlim->rlim_max)
4161                 return avc_has_perm(&selinux_state,
4162                                     current_sid(), task_sid(p),
4163                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4164
4165         return 0;
4166 }
4167
4168 static int selinux_task_setscheduler(struct task_struct *p)
4169 {
4170         return avc_has_perm(&selinux_state,
4171                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4172                             PROCESS__SETSCHED, NULL);
4173 }
4174
4175 static int selinux_task_getscheduler(struct task_struct *p)
4176 {
4177         return avc_has_perm(&selinux_state,
4178                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4179                             PROCESS__GETSCHED, NULL);
4180 }
4181
4182 static int selinux_task_movememory(struct task_struct *p)
4183 {
4184         return avc_has_perm(&selinux_state,
4185                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4186                             PROCESS__SETSCHED, NULL);
4187 }
4188
4189 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
4190                                 int sig, const struct cred *cred)
4191 {
4192         u32 secid;
4193         u32 perm;
4194
4195         if (!sig)
4196                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4197         else
4198                 perm = signal_to_av(sig);
4199         if (!cred)
4200                 secid = current_sid();
4201         else
4202                 secid = cred_sid(cred);
4203         return avc_has_perm(&selinux_state,
4204                             secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4205 }
4206
4207 static void selinux_task_to_inode(struct task_struct *p,
4208                                   struct inode *inode)
4209 {
4210         struct inode_security_struct *isec = inode->i_security;
4211         u32 sid = task_sid(p);
4212
4213         spin_lock(&isec->lock);
4214         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4215         isec->sid = sid;
4216         isec->initialized = LABEL_INITIALIZED;
4217         spin_unlock(&isec->lock);
4218 }
4219
4220 /* Returns error only if unable to parse addresses */
4221 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4222                         struct common_audit_data *ad, u8 *proto)
4223 {
4224         int offset, ihlen, ret = -EINVAL;
4225         struct iphdr _iph, *ih;
4226
4227         offset = skb_network_offset(skb);
4228         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4229         if (ih == NULL)
4230                 goto out;
4231
4232         ihlen = ih->ihl * 4;
4233         if (ihlen < sizeof(_iph))
4234                 goto out;
4235
4236         ad->u.net->v4info.saddr = ih->saddr;
4237         ad->u.net->v4info.daddr = ih->daddr;
4238         ret = 0;
4239
4240         if (proto)
4241                 *proto = ih->protocol;
4242
4243         switch (ih->protocol) {
4244         case IPPROTO_TCP: {
4245                 struct tcphdr _tcph, *th;
4246
4247                 if (ntohs(ih->frag_off) & IP_OFFSET)
4248                         break;
4249
4250                 offset += ihlen;
4251                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4252                 if (th == NULL)
4253                         break;
4254
4255                 ad->u.net->sport = th->source;
4256                 ad->u.net->dport = th->dest;
4257                 break;
4258         }
4259
4260         case IPPROTO_UDP: {
4261                 struct udphdr _udph, *uh;
4262
4263                 if (ntohs(ih->frag_off) & IP_OFFSET)
4264                         break;
4265
4266                 offset += ihlen;
4267                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4268                 if (uh == NULL)
4269                         break;
4270
4271                 ad->u.net->sport = uh->source;
4272                 ad->u.net->dport = uh->dest;
4273                 break;
4274         }
4275
4276         case IPPROTO_DCCP: {
4277                 struct dccp_hdr _dccph, *dh;
4278
4279                 if (ntohs(ih->frag_off) & IP_OFFSET)
4280                         break;
4281
4282                 offset += ihlen;
4283                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4284                 if (dh == NULL)
4285                         break;
4286
4287                 ad->u.net->sport = dh->dccph_sport;
4288                 ad->u.net->dport = dh->dccph_dport;
4289                 break;
4290         }
4291
4292 #if IS_ENABLED(CONFIG_IP_SCTP)
4293         case IPPROTO_SCTP: {
4294                 struct sctphdr _sctph, *sh;
4295
4296                 if (ntohs(ih->frag_off) & IP_OFFSET)
4297                         break;
4298
4299                 offset += ihlen;
4300                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4301                 if (sh == NULL)
4302                         break;
4303
4304                 ad->u.net->sport = sh->source;
4305                 ad->u.net->dport = sh->dest;
4306                 break;
4307         }
4308 #endif
4309         default:
4310                 break;
4311         }
4312 out:
4313         return ret;
4314 }
4315
4316 #if IS_ENABLED(CONFIG_IPV6)
4317
4318 /* Returns error only if unable to parse addresses */
4319 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4320                         struct common_audit_data *ad, u8 *proto)
4321 {
4322         u8 nexthdr;
4323         int ret = -EINVAL, offset;
4324         struct ipv6hdr _ipv6h, *ip6;
4325         __be16 frag_off;
4326
4327         offset = skb_network_offset(skb);
4328         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4329         if (ip6 == NULL)
4330                 goto out;
4331
4332         ad->u.net->v6info.saddr = ip6->saddr;
4333         ad->u.net->v6info.daddr = ip6->daddr;
4334         ret = 0;
4335
4336         nexthdr = ip6->nexthdr;
4337         offset += sizeof(_ipv6h);
4338         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4339         if (offset < 0)
4340                 goto out;
4341
4342         if (proto)
4343                 *proto = nexthdr;
4344
4345         switch (nexthdr) {
4346         case IPPROTO_TCP: {
4347                 struct tcphdr _tcph, *th;
4348
4349                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4350                 if (th == NULL)
4351                         break;
4352
4353                 ad->u.net->sport = th->source;
4354                 ad->u.net->dport = th->dest;
4355                 break;
4356         }
4357
4358         case IPPROTO_UDP: {
4359                 struct udphdr _udph, *uh;
4360
4361                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4362                 if (uh == NULL)
4363                         break;
4364
4365                 ad->u.net->sport = uh->source;
4366                 ad->u.net->dport = uh->dest;
4367                 break;
4368         }
4369
4370         case IPPROTO_DCCP: {
4371                 struct dccp_hdr _dccph, *dh;
4372
4373                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4374                 if (dh == NULL)
4375                         break;
4376
4377                 ad->u.net->sport = dh->dccph_sport;
4378                 ad->u.net->dport = dh->dccph_dport;
4379                 break;
4380         }
4381
4382 #if IS_ENABLED(CONFIG_IP_SCTP)
4383         case IPPROTO_SCTP: {
4384                 struct sctphdr _sctph, *sh;
4385
4386                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4387                 if (sh == NULL)
4388                         break;
4389
4390                 ad->u.net->sport = sh->source;
4391                 ad->u.net->dport = sh->dest;
4392                 break;
4393         }
4394 #endif
4395         /* includes fragments */
4396         default:
4397                 break;
4398         }
4399 out:
4400         return ret;
4401 }
4402
4403 #endif /* IPV6 */
4404
4405 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4406                              char **_addrp, int src, u8 *proto)
4407 {
4408         char *addrp;
4409         int ret;
4410
4411         switch (ad->u.net->family) {
4412         case PF_INET:
4413                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4414                 if (ret)
4415                         goto parse_error;
4416                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4417                                        &ad->u.net->v4info.daddr);
4418                 goto okay;
4419
4420 #if IS_ENABLED(CONFIG_IPV6)
4421         case PF_INET6:
4422                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4423                 if (ret)
4424                         goto parse_error;
4425                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4426                                        &ad->u.net->v6info.daddr);
4427                 goto okay;
4428 #endif  /* IPV6 */
4429         default:
4430                 addrp = NULL;
4431                 goto okay;
4432         }
4433
4434 parse_error:
4435         pr_warn(
4436                "SELinux: failure in selinux_parse_skb(),"
4437                " unable to parse packet\n");
4438         return ret;
4439
4440 okay:
4441         if (_addrp)
4442                 *_addrp = addrp;
4443         return 0;
4444 }
4445
4446 /**
4447  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4448  * @skb: the packet
4449  * @family: protocol family
4450  * @sid: the packet's peer label SID
4451  *
4452  * Description:
4453  * Check the various different forms of network peer labeling and determine
4454  * the peer label/SID for the packet; most of the magic actually occurs in
4455  * the security server function security_net_peersid_cmp().  The function
4456  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4457  * or -EACCES if @sid is invalid due to inconsistencies with the different
4458  * peer labels.
4459  *
4460  */
4461 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4462 {
4463         int err;
4464         u32 xfrm_sid;
4465         u32 nlbl_sid;
4466         u32 nlbl_type;
4467
4468         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4469         if (unlikely(err))
4470                 return -EACCES;
4471         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4472         if (unlikely(err))
4473                 return -EACCES;
4474
4475         err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4476                                            nlbl_type, xfrm_sid, sid);
4477         if (unlikely(err)) {
4478                 pr_warn(
4479                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4480                        " unable to determine packet's peer label\n");
4481                 return -EACCES;
4482         }
4483
4484         return 0;
4485 }
4486
4487 /**
4488  * selinux_conn_sid - Determine the child socket label for a connection
4489  * @sk_sid: the parent socket's SID
4490  * @skb_sid: the packet's SID
4491  * @conn_sid: the resulting connection SID
4492  *
4493  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4494  * combined with the MLS information from @skb_sid in order to create
4495  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4496  * of @sk_sid.  Returns zero on success, negative values on failure.
4497  *
4498  */
4499 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4500 {
4501         int err = 0;
4502
4503         if (skb_sid != SECSID_NULL)
4504                 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4505                                             conn_sid);
4506         else
4507                 *conn_sid = sk_sid;
4508
4509         return err;
4510 }
4511
4512 /* socket security operations */
4513
4514 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4515                                  u16 secclass, u32 *socksid)
4516 {
4517         if (tsec->sockcreate_sid > SECSID_NULL) {
4518                 *socksid = tsec->sockcreate_sid;
4519                 return 0;
4520         }
4521
4522         return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4523                                        secclass, NULL, socksid);
4524 }
4525
4526 static int sock_has_perm(struct sock *sk, u32 perms)
4527 {
4528         struct sk_security_struct *sksec = sk->sk_security;
4529         struct common_audit_data ad;
4530         struct lsm_network_audit net = {0,};
4531
4532         if (sksec->sid == SECINITSID_KERNEL)
4533                 return 0;
4534
4535         ad.type = LSM_AUDIT_DATA_NET;
4536         ad.u.net = &net;
4537         ad.u.net->sk = sk;
4538
4539         return avc_has_perm(&selinux_state,
4540                             current_sid(), sksec->sid, sksec->sclass, perms,
4541                             &ad);
4542 }
4543
4544 static int selinux_socket_create(int family, int type,
4545                                  int protocol, int kern)
4546 {
4547         const struct task_security_struct *tsec = current_security();
4548         u32 newsid;
4549         u16 secclass;
4550         int rc;
4551
4552         if (kern)
4553                 return 0;
4554
4555         secclass = socket_type_to_security_class(family, type, protocol);
4556         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4557         if (rc)
4558                 return rc;
4559
4560         return avc_has_perm(&selinux_state,
4561                             tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4562 }
4563
4564 static int selinux_socket_post_create(struct socket *sock, int family,
4565                                       int type, int protocol, int kern)
4566 {
4567         const struct task_security_struct *tsec = current_security();
4568         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4569         struct sk_security_struct *sksec;
4570         u16 sclass = socket_type_to_security_class(family, type, protocol);
4571         u32 sid = SECINITSID_KERNEL;
4572         int err = 0;
4573
4574         if (!kern) {
4575                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4576                 if (err)
4577                         return err;
4578         }
4579
4580         isec->sclass = sclass;
4581         isec->sid = sid;
4582         isec->initialized = LABEL_INITIALIZED;
4583
4584         if (sock->sk) {
4585                 sksec = sock->sk->sk_security;
4586                 sksec->sclass = sclass;
4587                 sksec->sid = sid;
4588                 /* Allows detection of the first association on this socket */
4589                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4590                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4591
4592                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4593         }
4594
4595         return err;
4596 }
4597
4598 static int selinux_socket_socketpair(struct socket *socka,
4599                                      struct socket *sockb)
4600 {
4601         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4602         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4603
4604         sksec_a->peer_sid = sksec_b->sid;
4605         sksec_b->peer_sid = sksec_a->sid;
4606
4607         return 0;
4608 }
4609
4610 /* Range of port numbers used to automatically bind.
4611    Need to determine whether we should perform a name_bind
4612    permission check between the socket and the port number. */
4613
4614 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4615 {
4616         struct sock *sk = sock->sk;
4617         struct sk_security_struct *sksec = sk->sk_security;
4618         u16 family;
4619         int err;
4620
4621         err = sock_has_perm(sk, SOCKET__BIND);
4622         if (err)
4623                 goto out;
4624
4625         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4626         family = sk->sk_family;
4627         if (family == PF_INET || family == PF_INET6) {
4628                 char *addrp;
4629                 struct common_audit_data ad;
4630                 struct lsm_network_audit net = {0,};
4631                 struct sockaddr_in *addr4 = NULL;
4632                 struct sockaddr_in6 *addr6 = NULL;
4633                 u16 family_sa = address->sa_family;
4634                 unsigned short snum;
4635                 u32 sid, node_perm;
4636
4637                 /*
4638                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4639                  * that validates multiple binding addresses. Because of this
4640                  * need to check address->sa_family as it is possible to have
4641                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4642                  */
4643                 switch (family_sa) {
4644                 case AF_UNSPEC:
4645                 case AF_INET:
4646                         if (addrlen < sizeof(struct sockaddr_in))
4647                                 return -EINVAL;
4648                         addr4 = (struct sockaddr_in *)address;
4649                         if (family_sa == AF_UNSPEC) {
4650                                 /* see __inet_bind(), we only want to allow
4651                                  * AF_UNSPEC if the address is INADDR_ANY
4652                                  */
4653                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4654                                         goto err_af;
4655                                 family_sa = AF_INET;
4656                         }
4657                         snum = ntohs(addr4->sin_port);
4658                         addrp = (char *)&addr4->sin_addr.s_addr;
4659                         break;
4660                 case AF_INET6:
4661                         if (addrlen < SIN6_LEN_RFC2133)
4662                                 return -EINVAL;
4663                         addr6 = (struct sockaddr_in6 *)address;
4664                         snum = ntohs(addr6->sin6_port);
4665                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4666                         break;
4667                 default:
4668                         goto err_af;
4669                 }
4670
4671                 ad.type = LSM_AUDIT_DATA_NET;
4672                 ad.u.net = &net;
4673                 ad.u.net->sport = htons(snum);
4674                 ad.u.net->family = family_sa;
4675
4676                 if (snum) {
4677                         int low, high;
4678
4679                         inet_get_local_port_range(sock_net(sk), &low, &high);
4680
4681                         if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
4682                             snum > high) {
4683                                 err = sel_netport_sid(sk->sk_protocol,
4684                                                       snum, &sid);
4685                                 if (err)
4686                                         goto out;
4687                                 err = avc_has_perm(&selinux_state,
4688                                                    sksec->sid, sid,
4689                                                    sksec->sclass,
4690                                                    SOCKET__NAME_BIND, &ad);
4691                                 if (err)
4692                                         goto out;
4693                         }
4694                 }
4695
4696                 switch (sksec->sclass) {
4697                 case SECCLASS_TCP_SOCKET:
4698                         node_perm = TCP_SOCKET__NODE_BIND;
4699                         break;
4700
4701                 case SECCLASS_UDP_SOCKET:
4702                         node_perm = UDP_SOCKET__NODE_BIND;
4703                         break;
4704
4705                 case SECCLASS_DCCP_SOCKET:
4706                         node_perm = DCCP_SOCKET__NODE_BIND;
4707                         break;
4708
4709                 case SECCLASS_SCTP_SOCKET:
4710                         node_perm = SCTP_SOCKET__NODE_BIND;
4711                         break;
4712
4713                 default:
4714                         node_perm = RAWIP_SOCKET__NODE_BIND;
4715                         break;
4716                 }
4717
4718                 err = sel_netnode_sid(addrp, family_sa, &sid);
4719                 if (err)
4720                         goto out;
4721
4722                 if (family_sa == AF_INET)
4723                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4724                 else
4725                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4726
4727                 err = avc_has_perm(&selinux_state,
4728                                    sksec->sid, sid,
4729                                    sksec->sclass, node_perm, &ad);
4730                 if (err)
4731                         goto out;
4732         }
4733 out:
4734         return err;
4735 err_af:
4736         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4737         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4738                 return -EINVAL;
4739         return -EAFNOSUPPORT;
4740 }
4741
4742 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4743  * and sctp_sendmsg(3) as described in Documentation/security/LSM-sctp.rst
4744  */
4745 static int selinux_socket_connect_helper(struct socket *sock,
4746                                          struct sockaddr *address, int addrlen)
4747 {
4748         struct sock *sk = sock->sk;
4749         struct sk_security_struct *sksec = sk->sk_security;
4750         int err;
4751
4752         err = sock_has_perm(sk, SOCKET__CONNECT);
4753         if (err)
4754                 return err;
4755
4756         /*
4757          * If a TCP, DCCP or SCTP socket, check name_connect permission
4758          * for the port.
4759          */
4760         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4761             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4762             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4763                 struct common_audit_data ad;
4764                 struct lsm_network_audit net = {0,};
4765                 struct sockaddr_in *addr4 = NULL;
4766                 struct sockaddr_in6 *addr6 = NULL;
4767                 unsigned short snum;
4768                 u32 sid, perm;
4769
4770                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4771                  * that validates multiple connect addresses. Because of this
4772                  * need to check address->sa_family as it is possible to have
4773                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4774                  */
4775                 switch (address->sa_family) {
4776                 case AF_INET:
4777                         addr4 = (struct sockaddr_in *)address;
4778                         if (addrlen < sizeof(struct sockaddr_in))
4779                                 return -EINVAL;
4780                         snum = ntohs(addr4->sin_port);
4781                         break;
4782                 case AF_INET6:
4783                         addr6 = (struct sockaddr_in6 *)address;
4784                         if (addrlen < SIN6_LEN_RFC2133)
4785                                 return -EINVAL;
4786                         snum = ntohs(addr6->sin6_port);
4787                         break;
4788                 default:
4789                         /* Note that SCTP services expect -EINVAL, whereas
4790                          * others expect -EAFNOSUPPORT.
4791                          */
4792                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4793                                 return -EINVAL;
4794                         else
4795                                 return -EAFNOSUPPORT;
4796                 }
4797
4798                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4799                 if (err)
4800                         return err;
4801
4802                 switch (sksec->sclass) {
4803                 case SECCLASS_TCP_SOCKET:
4804                         perm = TCP_SOCKET__NAME_CONNECT;
4805                         break;
4806                 case SECCLASS_DCCP_SOCKET:
4807                         perm = DCCP_SOCKET__NAME_CONNECT;
4808                         break;
4809                 case SECCLASS_SCTP_SOCKET:
4810                         perm = SCTP_SOCKET__NAME_CONNECT;
4811                         break;
4812                 }
4813
4814                 ad.type = LSM_AUDIT_DATA_NET;
4815                 ad.u.net = &net;
4816                 ad.u.net->dport = htons(snum);
4817                 ad.u.net->family = address->sa_family;
4818                 err = avc_has_perm(&selinux_state,
4819                                    sksec->sid, sid, sksec->sclass, perm, &ad);
4820                 if (err)
4821                         return err;
4822         }
4823
4824         return 0;
4825 }
4826
4827 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4828 static int selinux_socket_connect(struct socket *sock,
4829                                   struct sockaddr *address, int addrlen)
4830 {
4831         int err;
4832         struct sock *sk = sock->sk;
4833
4834         err = selinux_socket_connect_helper(sock, address, addrlen);
4835         if (err)
4836                 return err;
4837
4838         return selinux_netlbl_socket_connect(sk, address);
4839 }
4840
4841 static int selinux_socket_listen(struct socket *sock, int backlog)
4842 {
4843         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4844 }
4845
4846 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4847 {
4848         int err;
4849         struct inode_security_struct *isec;
4850         struct inode_security_struct *newisec;
4851         u16 sclass;
4852         u32 sid;
4853
4854         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4855         if (err)
4856                 return err;
4857
4858         isec = inode_security_novalidate(SOCK_INODE(sock));
4859         spin_lock(&isec->lock);
4860         sclass = isec->sclass;
4861         sid = isec->sid;
4862         spin_unlock(&isec->lock);
4863
4864         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4865         newisec->sclass = sclass;
4866         newisec->sid = sid;
4867         newisec->initialized = LABEL_INITIALIZED;
4868
4869         return 0;
4870 }
4871
4872 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4873                                   int size)
4874 {
4875         return sock_has_perm(sock->sk, SOCKET__WRITE);
4876 }
4877
4878 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4879                                   int size, int flags)
4880 {
4881         return sock_has_perm(sock->sk, SOCKET__READ);
4882 }
4883
4884 static int selinux_socket_getsockname(struct socket *sock)
4885 {
4886         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4887 }
4888
4889 static int selinux_socket_getpeername(struct socket *sock)
4890 {
4891         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4892 }
4893
4894 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4895 {
4896         int err;
4897
4898         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4899         if (err)
4900                 return err;
4901
4902         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4903 }
4904
4905 static int selinux_socket_getsockopt(struct socket *sock, int level,
4906                                      int optname)
4907 {
4908         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4909 }
4910
4911 static int selinux_socket_shutdown(struct socket *sock, int how)
4912 {
4913         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4914 }
4915
4916 static int selinux_socket_unix_stream_connect(struct sock *sock,
4917                                               struct sock *other,
4918                                               struct sock *newsk)
4919 {
4920         struct sk_security_struct *sksec_sock = sock->sk_security;
4921         struct sk_security_struct *sksec_other = other->sk_security;
4922         struct sk_security_struct *sksec_new = newsk->sk_security;
4923         struct common_audit_data ad;
4924         struct lsm_network_audit net = {0,};
4925         int err;
4926
4927         ad.type = LSM_AUDIT_DATA_NET;
4928         ad.u.net = &net;
4929         ad.u.net->sk = other;
4930
4931         err = avc_has_perm(&selinux_state,
4932                            sksec_sock->sid, sksec_other->sid,
4933                            sksec_other->sclass,
4934                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4935         if (err)
4936                 return err;
4937
4938         /* server child socket */
4939         sksec_new->peer_sid = sksec_sock->sid;
4940         err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4941                                     sksec_sock->sid, &sksec_new->sid);
4942         if (err)
4943                 return err;
4944
4945         /* connecting socket */
4946         sksec_sock->peer_sid = sksec_new->sid;
4947
4948         return 0;
4949 }
4950
4951 static int selinux_socket_unix_may_send(struct socket *sock,
4952                                         struct socket *other)
4953 {
4954         struct sk_security_struct *ssec = sock->sk->sk_security;
4955         struct sk_security_struct *osec = other->sk->sk_security;
4956         struct common_audit_data ad;
4957         struct lsm_network_audit net = {0,};
4958
4959         ad.type = LSM_AUDIT_DATA_NET;
4960         ad.u.net = &net;
4961         ad.u.net->sk = other->sk;
4962
4963         return avc_has_perm(&selinux_state,
4964                             ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4965                             &ad);
4966 }
4967
4968 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4969                                     char *addrp, u16 family, u32 peer_sid,
4970                                     struct common_audit_data *ad)
4971 {
4972         int err;
4973         u32 if_sid;
4974         u32 node_sid;
4975
4976         err = sel_netif_sid(ns, ifindex, &if_sid);
4977         if (err)
4978                 return err;
4979         err = avc_has_perm(&selinux_state,
4980                            peer_sid, if_sid,
4981                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4982         if (err)
4983                 return err;
4984
4985         err = sel_netnode_sid(addrp, family, &node_sid);
4986         if (err)
4987                 return err;
4988         return avc_has_perm(&selinux_state,
4989                             peer_sid, node_sid,
4990                             SECCLASS_NODE, NODE__RECVFROM, ad);
4991 }
4992
4993 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4994                                        u16 family)
4995 {
4996         int err = 0;
4997         struct sk_security_struct *sksec = sk->sk_security;
4998         u32 sk_sid = sksec->sid;
4999         struct common_audit_data ad;
5000         struct lsm_network_audit net = {0,};
5001         char *addrp;
5002
5003         ad.type = LSM_AUDIT_DATA_NET;
5004         ad.u.net = &net;
5005         ad.u.net->netif = skb->skb_iif;
5006         ad.u.net->family = family;
5007         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5008         if (err)
5009                 return err;
5010
5011         if (selinux_secmark_enabled()) {
5012                 err = avc_has_perm(&selinux_state,
5013                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5014                                    PACKET__RECV, &ad);
5015                 if (err)
5016                         return err;
5017         }
5018
5019         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5020         if (err)
5021                 return err;
5022         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5023
5024         return err;
5025 }
5026
5027 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5028 {
5029         int err;
5030         struct sk_security_struct *sksec = sk->sk_security;
5031         u16 family = sk->sk_family;
5032         u32 sk_sid = sksec->sid;
5033         struct common_audit_data ad;
5034         struct lsm_network_audit net = {0,};
5035         char *addrp;
5036         u8 secmark_active;
5037         u8 peerlbl_active;
5038
5039         if (family != PF_INET && family != PF_INET6)
5040                 return 0;
5041
5042         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5043         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5044                 family = PF_INET;
5045
5046         /* If any sort of compatibility mode is enabled then handoff processing
5047          * to the selinux_sock_rcv_skb_compat() function to deal with the
5048          * special handling.  We do this in an attempt to keep this function
5049          * as fast and as clean as possible. */
5050         if (!selinux_policycap_netpeer())
5051                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5052
5053         secmark_active = selinux_secmark_enabled();
5054         peerlbl_active = selinux_peerlbl_enabled();
5055         if (!secmark_active && !peerlbl_active)
5056                 return 0;
5057
5058         ad.type = LSM_AUDIT_DATA_NET;
5059         ad.u.net = &net;
5060         ad.u.net->netif = skb->skb_iif;
5061         ad.u.net->family = family;
5062         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5063         if (err)
5064                 return err;
5065
5066         if (peerlbl_active) {
5067                 u32 peer_sid;
5068
5069                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5070                 if (err)
5071                         return err;
5072                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5073                                                addrp, family, peer_sid, &ad);
5074                 if (err) {
5075                         selinux_netlbl_err(skb, family, err, 0);
5076                         return err;
5077                 }
5078                 err = avc_has_perm(&selinux_state,
5079                                    sk_sid, peer_sid, SECCLASS_PEER,
5080                                    PEER__RECV, &ad);
5081                 if (err) {
5082                         selinux_netlbl_err(skb, family, err, 0);
5083                         return err;
5084                 }
5085         }
5086
5087         if (secmark_active) {
5088                 err = avc_has_perm(&selinux_state,
5089                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5090                                    PACKET__RECV, &ad);
5091                 if (err)
5092                         return err;
5093         }
5094
5095         return err;
5096 }
5097
5098 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5099                                             int __user *optlen, unsigned len)
5100 {
5101         int err = 0;
5102         char *scontext;
5103         u32 scontext_len;
5104         struct sk_security_struct *sksec = sock->sk->sk_security;
5105         u32 peer_sid = SECSID_NULL;
5106
5107         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5108             sksec->sclass == SECCLASS_TCP_SOCKET ||
5109             sksec->sclass == SECCLASS_SCTP_SOCKET)
5110                 peer_sid = sksec->peer_sid;
5111         if (peer_sid == SECSID_NULL)
5112                 return -ENOPROTOOPT;
5113
5114         err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5115                                       &scontext_len);
5116         if (err)
5117                 return err;
5118
5119         if (scontext_len > len) {
5120                 err = -ERANGE;
5121                 goto out_len;
5122         }
5123
5124         if (copy_to_user(optval, scontext, scontext_len))
5125                 err = -EFAULT;
5126
5127 out_len:
5128         if (put_user(scontext_len, optlen))
5129                 err = -EFAULT;
5130         kfree(scontext);
5131         return err;
5132 }
5133
5134 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5135 {
5136         u32 peer_secid = SECSID_NULL;
5137         u16 family;
5138         struct inode_security_struct *isec;
5139
5140         if (skb && skb->protocol == htons(ETH_P_IP))
5141                 family = PF_INET;
5142         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5143                 family = PF_INET6;
5144         else if (sock)
5145                 family = sock->sk->sk_family;
5146         else
5147                 goto out;
5148
5149         if (sock && family == PF_UNIX) {
5150                 isec = inode_security_novalidate(SOCK_INODE(sock));
5151                 peer_secid = isec->sid;
5152         } else if (skb)
5153                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5154
5155 out:
5156         *secid = peer_secid;
5157         if (peer_secid == SECSID_NULL)
5158                 return -EINVAL;
5159         return 0;
5160 }
5161
5162 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5163 {
5164         struct sk_security_struct *sksec;
5165
5166         sksec = kzalloc(sizeof(*sksec), priority);
5167         if (!sksec)
5168                 return -ENOMEM;
5169
5170         sksec->peer_sid = SECINITSID_UNLABELED;
5171         sksec->sid = SECINITSID_UNLABELED;
5172         sksec->sclass = SECCLASS_SOCKET;
5173         selinux_netlbl_sk_security_reset(sksec);
5174         sk->sk_security = sksec;
5175
5176         return 0;
5177 }
5178
5179 static void selinux_sk_free_security(struct sock *sk)
5180 {
5181         struct sk_security_struct *sksec = sk->sk_security;
5182
5183         sk->sk_security = NULL;
5184         selinux_netlbl_sk_security_free(sksec);
5185         kfree(sksec);
5186 }
5187
5188 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5189 {
5190         struct sk_security_struct *sksec = sk->sk_security;
5191         struct sk_security_struct *newsksec = newsk->sk_security;
5192
5193         newsksec->sid = sksec->sid;
5194         newsksec->peer_sid = sksec->peer_sid;
5195         newsksec->sclass = sksec->sclass;
5196
5197         selinux_netlbl_sk_security_reset(newsksec);
5198 }
5199
5200 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5201 {
5202         if (!sk)
5203                 *secid = SECINITSID_ANY_SOCKET;
5204         else {
5205                 struct sk_security_struct *sksec = sk->sk_security;
5206
5207                 *secid = sksec->sid;
5208         }
5209 }
5210
5211 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5212 {
5213         struct inode_security_struct *isec =
5214                 inode_security_novalidate(SOCK_INODE(parent));
5215         struct sk_security_struct *sksec = sk->sk_security;
5216
5217         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5218             sk->sk_family == PF_UNIX)
5219                 isec->sid = sksec->sid;
5220         sksec->sclass = isec->sclass;
5221 }
5222
5223 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5224  * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5225  * already present).
5226  */
5227 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5228                                       struct sk_buff *skb)
5229 {
5230         struct sk_security_struct *sksec = ep->base.sk->sk_security;
5231         struct common_audit_data ad;
5232         struct lsm_network_audit net = {0,};
5233         u8 peerlbl_active;
5234         u32 peer_sid = SECINITSID_UNLABELED;
5235         u32 conn_sid;
5236         int err = 0;
5237
5238         if (!selinux_policycap_extsockclass())
5239                 return 0;
5240
5241         peerlbl_active = selinux_peerlbl_enabled();
5242
5243         if (peerlbl_active) {
5244                 /* This will return peer_sid = SECSID_NULL if there are
5245                  * no peer labels, see security_net_peersid_resolve().
5246                  */
5247                 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5248                                               &peer_sid);
5249                 if (err)
5250                         return err;
5251
5252                 if (peer_sid == SECSID_NULL)
5253                         peer_sid = SECINITSID_UNLABELED;
5254         }
5255
5256         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5257                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5258
5259                 /* Here as first association on socket. As the peer SID
5260                  * was allowed by peer recv (and the netif/node checks),
5261                  * then it is approved by policy and used as the primary
5262                  * peer SID for getpeercon(3).
5263                  */
5264                 sksec->peer_sid = peer_sid;
5265         } else if  (sksec->peer_sid != peer_sid) {
5266                 /* Other association peer SIDs are checked to enforce
5267                  * consistency among the peer SIDs.
5268                  */
5269                 ad.type = LSM_AUDIT_DATA_NET;
5270                 ad.u.net = &net;
5271                 ad.u.net->sk = ep->base.sk;
5272                 err = avc_has_perm(&selinux_state,
5273                                    sksec->peer_sid, peer_sid, sksec->sclass,
5274                                    SCTP_SOCKET__ASSOCIATION, &ad);
5275                 if (err)
5276                         return err;
5277         }
5278
5279         /* Compute the MLS component for the connection and store
5280          * the information in ep. This will be used by SCTP TCP type
5281          * sockets and peeled off connections as they cause a new
5282          * socket to be generated. selinux_sctp_sk_clone() will then
5283          * plug this into the new socket.
5284          */
5285         err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5286         if (err)
5287                 return err;
5288
5289         ep->secid = conn_sid;
5290         ep->peer_secid = peer_sid;
5291
5292         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5293         return selinux_netlbl_sctp_assoc_request(ep, skb);
5294 }
5295
5296 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5297  * based on their @optname.
5298  */
5299 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5300                                      struct sockaddr *address,
5301                                      int addrlen)
5302 {
5303         int len, err = 0, walk_size = 0;
5304         void *addr_buf;
5305         struct sockaddr *addr;
5306         struct socket *sock;
5307
5308         if (!selinux_policycap_extsockclass())
5309                 return 0;
5310
5311         /* Process one or more addresses that may be IPv4 or IPv6 */
5312         sock = sk->sk_socket;
5313         addr_buf = address;
5314
5315         while (walk_size < addrlen) {
5316                 addr = addr_buf;
5317                 switch (addr->sa_family) {
5318                 case AF_UNSPEC:
5319                 case AF_INET:
5320                         len = sizeof(struct sockaddr_in);
5321                         break;
5322                 case AF_INET6:
5323                         len = sizeof(struct sockaddr_in6);
5324                         break;
5325                 default:
5326                         return -EINVAL;
5327                 }
5328
5329                 err = -EINVAL;
5330                 switch (optname) {
5331                 /* Bind checks */
5332                 case SCTP_PRIMARY_ADDR:
5333                 case SCTP_SET_PEER_PRIMARY_ADDR:
5334                 case SCTP_SOCKOPT_BINDX_ADD:
5335                         err = selinux_socket_bind(sock, addr, len);
5336                         break;
5337                 /* Connect checks */
5338                 case SCTP_SOCKOPT_CONNECTX:
5339                 case SCTP_PARAM_SET_PRIMARY:
5340                 case SCTP_PARAM_ADD_IP:
5341                 case SCTP_SENDMSG_CONNECT:
5342                         err = selinux_socket_connect_helper(sock, addr, len);
5343                         if (err)
5344                                 return err;
5345
5346                         /* As selinux_sctp_bind_connect() is called by the
5347                          * SCTP protocol layer, the socket is already locked,
5348                          * therefore selinux_netlbl_socket_connect_locked() is
5349                          * is called here. The situations handled are:
5350                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5351                          * whenever a new IP address is added or when a new
5352                          * primary address is selected.
5353                          * Note that an SCTP connect(2) call happens before
5354                          * the SCTP protocol layer and is handled via
5355                          * selinux_socket_connect().
5356                          */
5357                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5358                         break;
5359                 }
5360
5361                 if (err)
5362                         return err;
5363
5364                 addr_buf += len;
5365                 walk_size += len;
5366         }
5367
5368         return 0;
5369 }
5370
5371 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5372 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5373                                   struct sock *newsk)
5374 {
5375         struct sk_security_struct *sksec = sk->sk_security;
5376         struct sk_security_struct *newsksec = newsk->sk_security;
5377
5378         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5379          * the non-sctp clone version.
5380          */
5381         if (!selinux_policycap_extsockclass())
5382                 return selinux_sk_clone_security(sk, newsk);
5383
5384         newsksec->sid = ep->secid;
5385         newsksec->peer_sid = ep->peer_secid;
5386         newsksec->sclass = sksec->sclass;
5387         selinux_netlbl_sctp_sk_clone(sk, newsk);
5388 }
5389
5390 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5391                                      struct request_sock *req)
5392 {
5393         struct sk_security_struct *sksec = sk->sk_security;
5394         int err;
5395         u16 family = req->rsk_ops->family;
5396         u32 connsid;
5397         u32 peersid;
5398
5399         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5400         if (err)
5401                 return err;
5402         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5403         if (err)
5404                 return err;
5405         req->secid = connsid;
5406         req->peer_secid = peersid;
5407
5408         return selinux_netlbl_inet_conn_request(req, family);
5409 }
5410
5411 static void selinux_inet_csk_clone(struct sock *newsk,
5412                                    const struct request_sock *req)
5413 {
5414         struct sk_security_struct *newsksec = newsk->sk_security;
5415
5416         newsksec->sid = req->secid;
5417         newsksec->peer_sid = req->peer_secid;
5418         /* NOTE: Ideally, we should also get the isec->sid for the
5419            new socket in sync, but we don't have the isec available yet.
5420            So we will wait until sock_graft to do it, by which
5421            time it will have been created and available. */
5422
5423         /* We don't need to take any sort of lock here as we are the only
5424          * thread with access to newsksec */
5425         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5426 }
5427
5428 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5429 {
5430         u16 family = sk->sk_family;
5431         struct sk_security_struct *sksec = sk->sk_security;
5432
5433         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5434         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5435                 family = PF_INET;
5436
5437         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5438 }
5439
5440 static int selinux_secmark_relabel_packet(u32 sid)
5441 {
5442         const struct task_security_struct *__tsec;
5443         u32 tsid;
5444
5445         __tsec = current_security();
5446         tsid = __tsec->sid;
5447
5448         return avc_has_perm(&selinux_state,
5449                             tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5450                             NULL);
5451 }
5452
5453 static void selinux_secmark_refcount_inc(void)
5454 {
5455         atomic_inc(&selinux_secmark_refcount);
5456 }
5457
5458 static void selinux_secmark_refcount_dec(void)
5459 {
5460         atomic_dec(&selinux_secmark_refcount);
5461 }
5462
5463 static void selinux_req_classify_flow(const struct request_sock *req,
5464                                       struct flowi *fl)
5465 {
5466         fl->flowi_secid = req->secid;
5467 }
5468
5469 static int selinux_tun_dev_alloc_security(void **security)
5470 {
5471         struct tun_security_struct *tunsec;
5472
5473         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5474         if (!tunsec)
5475                 return -ENOMEM;
5476         tunsec->sid = current_sid();
5477
5478         *security = tunsec;
5479         return 0;
5480 }
5481
5482 static void selinux_tun_dev_free_security(void *security)
5483 {
5484         kfree(security);
5485 }
5486
5487 static int selinux_tun_dev_create(void)
5488 {
5489         u32 sid = current_sid();
5490
5491         /* we aren't taking into account the "sockcreate" SID since the socket
5492          * that is being created here is not a socket in the traditional sense,
5493          * instead it is a private sock, accessible only to the kernel, and
5494          * representing a wide range of network traffic spanning multiple
5495          * connections unlike traditional sockets - check the TUN driver to
5496          * get a better understanding of why this socket is special */
5497
5498         return avc_has_perm(&selinux_state,
5499                             sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5500                             NULL);
5501 }
5502
5503 static int selinux_tun_dev_attach_queue(void *security)
5504 {
5505         struct tun_security_struct *tunsec = security;
5506
5507         return avc_has_perm(&selinux_state,
5508                             current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5509                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5510 }
5511
5512 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5513 {
5514         struct tun_security_struct *tunsec = security;
5515         struct sk_security_struct *sksec = sk->sk_security;
5516
5517         /* we don't currently perform any NetLabel based labeling here and it
5518          * isn't clear that we would want to do so anyway; while we could apply
5519          * labeling without the support of the TUN user the resulting labeled
5520          * traffic from the other end of the connection would almost certainly
5521          * cause confusion to the TUN user that had no idea network labeling
5522          * protocols were being used */
5523
5524         sksec->sid = tunsec->sid;
5525         sksec->sclass = SECCLASS_TUN_SOCKET;
5526
5527         return 0;
5528 }
5529
5530 static int selinux_tun_dev_open(void *security)
5531 {
5532         struct tun_security_struct *tunsec = security;
5533         u32 sid = current_sid();
5534         int err;
5535
5536         err = avc_has_perm(&selinux_state,
5537                            sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5538                            TUN_SOCKET__RELABELFROM, NULL);
5539         if (err)
5540                 return err;
5541         err = avc_has_perm(&selinux_state,
5542                            sid, sid, SECCLASS_TUN_SOCKET,
5543                            TUN_SOCKET__RELABELTO, NULL);
5544         if (err)
5545                 return err;
5546         tunsec->sid = sid;
5547
5548         return 0;
5549 }
5550
5551 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5552 {
5553         int err = 0;
5554         u32 perm;
5555         struct nlmsghdr *nlh;
5556         struct sk_security_struct *sksec = sk->sk_security;
5557
5558         if (skb->len < NLMSG_HDRLEN) {
5559                 err = -EINVAL;
5560                 goto out;
5561         }
5562         nlh = nlmsg_hdr(skb);
5563
5564         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5565         if (err) {
5566                 if (err == -EINVAL) {
5567                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5568                                " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5569                                " pig=%d comm=%s\n",
5570                                sk->sk_protocol, nlh->nlmsg_type,
5571                                secclass_map[sksec->sclass - 1].name,
5572                                task_pid_nr(current), current->comm);
5573                         if (!enforcing_enabled(&selinux_state) ||
5574                             security_get_allow_unknown(&selinux_state))
5575                                 err = 0;
5576                 }
5577
5578                 /* Ignore */
5579                 if (err == -ENOENT)
5580                         err = 0;
5581                 goto out;
5582         }
5583
5584         err = sock_has_perm(sk, perm);
5585 out:
5586         return err;
5587 }
5588
5589 #ifdef CONFIG_NETFILTER
5590
5591 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5592                                        const struct net_device *indev,
5593                                        u16 family)
5594 {
5595         int err;
5596         char *addrp;
5597         u32 peer_sid;
5598         struct common_audit_data ad;
5599         struct lsm_network_audit net = {0,};
5600         u8 secmark_active;
5601         u8 netlbl_active;
5602         u8 peerlbl_active;
5603
5604         if (!selinux_policycap_netpeer())
5605                 return NF_ACCEPT;
5606
5607         secmark_active = selinux_secmark_enabled();
5608         netlbl_active = netlbl_enabled();
5609         peerlbl_active = selinux_peerlbl_enabled();
5610         if (!secmark_active && !peerlbl_active)
5611                 return NF_ACCEPT;
5612
5613         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5614                 return NF_DROP;
5615
5616         ad.type = LSM_AUDIT_DATA_NET;
5617         ad.u.net = &net;
5618         ad.u.net->netif = indev->ifindex;
5619         ad.u.net->family = family;
5620         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5621                 return NF_DROP;
5622
5623         if (peerlbl_active) {
5624                 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5625                                                addrp, family, peer_sid, &ad);
5626                 if (err) {
5627                         selinux_netlbl_err(skb, family, err, 1);
5628                         return NF_DROP;
5629                 }
5630         }
5631
5632         if (secmark_active)
5633                 if (avc_has_perm(&selinux_state,
5634                                  peer_sid, skb->secmark,
5635                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5636                         return NF_DROP;
5637
5638         if (netlbl_active)
5639                 /* we do this in the FORWARD path and not the POST_ROUTING
5640                  * path because we want to make sure we apply the necessary
5641                  * labeling before IPsec is applied so we can leverage AH
5642                  * protection */
5643                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5644                         return NF_DROP;
5645
5646         return NF_ACCEPT;
5647 }
5648
5649 static unsigned int selinux_ipv4_forward(void *priv,
5650                                          struct sk_buff *skb,
5651                                          const struct nf_hook_state *state)
5652 {
5653         return selinux_ip_forward(skb, state->in, PF_INET);
5654 }
5655
5656 #if IS_ENABLED(CONFIG_IPV6)
5657 static unsigned int selinux_ipv6_forward(void *priv,
5658                                          struct sk_buff *skb,
5659                                          const struct nf_hook_state *state)
5660 {
5661         return selinux_ip_forward(skb, state->in, PF_INET6);
5662 }
5663 #endif  /* IPV6 */
5664
5665 static unsigned int selinux_ip_output(struct sk_buff *skb,
5666                                       u16 family)
5667 {
5668         struct sock *sk;
5669         u32 sid;
5670
5671         if (!netlbl_enabled())
5672                 return NF_ACCEPT;
5673
5674         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5675          * because we want to make sure we apply the necessary labeling
5676          * before IPsec is applied so we can leverage AH protection */
5677         sk = skb->sk;
5678         if (sk) {
5679                 struct sk_security_struct *sksec;
5680
5681                 if (sk_listener(sk))
5682                         /* if the socket is the listening state then this
5683                          * packet is a SYN-ACK packet which means it needs to
5684                          * be labeled based on the connection/request_sock and
5685                          * not the parent socket.  unfortunately, we can't
5686                          * lookup the request_sock yet as it isn't queued on
5687                          * the parent socket until after the SYN-ACK is sent.
5688                          * the "solution" is to simply pass the packet as-is
5689                          * as any IP option based labeling should be copied
5690                          * from the initial connection request (in the IP
5691                          * layer).  it is far from ideal, but until we get a
5692                          * security label in the packet itself this is the
5693                          * best we can do. */
5694                         return NF_ACCEPT;
5695
5696                 /* standard practice, label using the parent socket */
5697                 sksec = sk->sk_security;
5698                 sid = sksec->sid;
5699         } else
5700                 sid = SECINITSID_KERNEL;
5701         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5702                 return NF_DROP;
5703
5704         return NF_ACCEPT;
5705 }
5706
5707 static unsigned int selinux_ipv4_output(void *priv,
5708                                         struct sk_buff *skb,
5709                                         const struct nf_hook_state *state)
5710 {
5711         return selinux_ip_output(skb, PF_INET);
5712 }
5713
5714 #if IS_ENABLED(CONFIG_IPV6)
5715 static unsigned int selinux_ipv6_output(void *priv,
5716                                         struct sk_buff *skb,
5717                                         const struct nf_hook_state *state)
5718 {
5719         return selinux_ip_output(skb, PF_INET6);
5720 }
5721 #endif  /* IPV6 */
5722
5723 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5724                                                 int ifindex,
5725                                                 u16 family)
5726 {
5727         struct sock *sk = skb_to_full_sk(skb);
5728         struct sk_security_struct *sksec;
5729         struct common_audit_data ad;
5730         struct lsm_network_audit net = {0,};
5731         char *addrp;
5732         u8 proto;
5733
5734         if (sk == NULL)
5735                 return NF_ACCEPT;
5736         sksec = sk->sk_security;
5737
5738         ad.type = LSM_AUDIT_DATA_NET;
5739         ad.u.net = &net;
5740         ad.u.net->netif = ifindex;
5741         ad.u.net->family = family;
5742         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5743                 return NF_DROP;
5744
5745         if (selinux_secmark_enabled())
5746                 if (avc_has_perm(&selinux_state,
5747                                  sksec->sid, skb->secmark,
5748                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5749                         return NF_DROP_ERR(-ECONNREFUSED);
5750
5751         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5752                 return NF_DROP_ERR(-ECONNREFUSED);
5753
5754         return NF_ACCEPT;
5755 }
5756
5757 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5758                                          const struct net_device *outdev,
5759                                          u16 family)
5760 {
5761         u32 secmark_perm;
5762         u32 peer_sid;
5763         int ifindex = outdev->ifindex;
5764         struct sock *sk;
5765         struct common_audit_data ad;
5766         struct lsm_network_audit net = {0,};
5767         char *addrp;
5768         u8 secmark_active;
5769         u8 peerlbl_active;
5770
5771         /* If any sort of compatibility mode is enabled then handoff processing
5772          * to the selinux_ip_postroute_compat() function to deal with the
5773          * special handling.  We do this in an attempt to keep this function
5774          * as fast and as clean as possible. */
5775         if (!selinux_policycap_netpeer())
5776                 return selinux_ip_postroute_compat(skb, ifindex, family);
5777
5778         secmark_active = selinux_secmark_enabled();
5779         peerlbl_active = selinux_peerlbl_enabled();
5780         if (!secmark_active && !peerlbl_active)
5781                 return NF_ACCEPT;
5782
5783         sk = skb_to_full_sk(skb);
5784
5785 #ifdef CONFIG_XFRM
5786         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5787          * packet transformation so allow the packet to pass without any checks
5788          * since we'll have another chance to perform access control checks
5789          * when the packet is on it's final way out.
5790          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5791          *       is NULL, in this case go ahead and apply access control.
5792          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5793          *       TCP listening state we cannot wait until the XFRM processing
5794          *       is done as we will miss out on the SA label if we do;
5795          *       unfortunately, this means more work, but it is only once per
5796          *       connection. */
5797         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5798             !(sk && sk_listener(sk)))
5799                 return NF_ACCEPT;
5800 #endif
5801
5802         if (sk == NULL) {
5803                 /* Without an associated socket the packet is either coming
5804                  * from the kernel or it is being forwarded; check the packet
5805                  * to determine which and if the packet is being forwarded
5806                  * query the packet directly to determine the security label. */
5807                 if (skb->skb_iif) {
5808                         secmark_perm = PACKET__FORWARD_OUT;
5809                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5810                                 return NF_DROP;
5811                 } else {
5812                         secmark_perm = PACKET__SEND;
5813                         peer_sid = SECINITSID_KERNEL;
5814                 }
5815         } else if (sk_listener(sk)) {
5816                 /* Locally generated packet but the associated socket is in the
5817                  * listening state which means this is a SYN-ACK packet.  In
5818                  * this particular case the correct security label is assigned
5819                  * to the connection/request_sock but unfortunately we can't
5820                  * query the request_sock as it isn't queued on the parent
5821                  * socket until after the SYN-ACK packet is sent; the only
5822                  * viable choice is to regenerate the label like we do in
5823                  * selinux_inet_conn_request().  See also selinux_ip_output()
5824                  * for similar problems. */
5825                 u32 skb_sid;
5826                 struct sk_security_struct *sksec;
5827
5828                 sksec = sk->sk_security;
5829                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5830                         return NF_DROP;
5831                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5832                  * and the packet has been through at least one XFRM
5833                  * transformation then we must be dealing with the "final"
5834                  * form of labeled IPsec packet; since we've already applied
5835                  * all of our access controls on this packet we can safely
5836                  * pass the packet. */
5837                 if (skb_sid == SECSID_NULL) {
5838                         switch (family) {
5839                         case PF_INET:
5840                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5841                                         return NF_ACCEPT;
5842                                 break;
5843                         case PF_INET6:
5844                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5845                                         return NF_ACCEPT;
5846                                 break;
5847                         default:
5848                                 return NF_DROP_ERR(-ECONNREFUSED);
5849                         }
5850                 }
5851                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5852                         return NF_DROP;
5853                 secmark_perm = PACKET__SEND;
5854         } else {
5855                 /* Locally generated packet, fetch the security label from the
5856                  * associated socket. */
5857                 struct sk_security_struct *sksec = sk->sk_security;
5858                 peer_sid = sksec->sid;
5859                 secmark_perm = PACKET__SEND;
5860         }
5861
5862         ad.type = LSM_AUDIT_DATA_NET;
5863         ad.u.net = &net;
5864         ad.u.net->netif = ifindex;
5865         ad.u.net->family = family;
5866         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5867                 return NF_DROP;
5868
5869         if (secmark_active)
5870                 if (avc_has_perm(&selinux_state,
5871                                  peer_sid, skb->secmark,
5872                                  SECCLASS_PACKET, secmark_perm, &ad))
5873                         return NF_DROP_ERR(-ECONNREFUSED);
5874
5875         if (peerlbl_active) {
5876                 u32 if_sid;
5877                 u32 node_sid;
5878
5879                 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5880                         return NF_DROP;
5881                 if (avc_has_perm(&selinux_state,
5882                                  peer_sid, if_sid,
5883                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5884                         return NF_DROP_ERR(-ECONNREFUSED);
5885
5886                 if (sel_netnode_sid(addrp, family, &node_sid))
5887                         return NF_DROP;
5888                 if (avc_has_perm(&selinux_state,
5889                                  peer_sid, node_sid,
5890                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5891                         return NF_DROP_ERR(-ECONNREFUSED);
5892         }
5893
5894         return NF_ACCEPT;
5895 }
5896
5897 static unsigned int selinux_ipv4_postroute(void *priv,
5898                                            struct sk_buff *skb,
5899                                            const struct nf_hook_state *state)
5900 {
5901         return selinux_ip_postroute(skb, state->out, PF_INET);
5902 }
5903
5904 #if IS_ENABLED(CONFIG_IPV6)
5905 static unsigned int selinux_ipv6_postroute(void *priv,
5906                                            struct sk_buff *skb,
5907                                            const struct nf_hook_state *state)
5908 {
5909         return selinux_ip_postroute(skb, state->out, PF_INET6);
5910 }
5911 #endif  /* IPV6 */
5912
5913 #endif  /* CONFIG_NETFILTER */
5914
5915 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5916 {
5917         return selinux_nlmsg_perm(sk, skb);
5918 }
5919
5920 static int ipc_alloc_security(struct kern_ipc_perm *perm,
5921                               u16 sclass)
5922 {
5923         struct ipc_security_struct *isec;
5924
5925         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5926         if (!isec)
5927                 return -ENOMEM;
5928
5929         isec->sclass = sclass;
5930         isec->sid = current_sid();
5931         perm->security = isec;
5932
5933         return 0;
5934 }
5935
5936 static void ipc_free_security(struct kern_ipc_perm *perm)
5937 {
5938         struct ipc_security_struct *isec = perm->security;
5939         perm->security = NULL;
5940         kfree(isec);
5941 }
5942
5943 static int msg_msg_alloc_security(struct msg_msg *msg)
5944 {
5945         struct msg_security_struct *msec;
5946
5947         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5948         if (!msec)
5949                 return -ENOMEM;
5950
5951         msec->sid = SECINITSID_UNLABELED;
5952         msg->security = msec;
5953
5954         return 0;
5955 }
5956
5957 static void msg_msg_free_security(struct msg_msg *msg)
5958 {
5959         struct msg_security_struct *msec = msg->security;
5960
5961         msg->security = NULL;
5962         kfree(msec);
5963 }
5964
5965 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5966                         u32 perms)
5967 {
5968         struct ipc_security_struct *isec;
5969         struct common_audit_data ad;
5970         u32 sid = current_sid();
5971
5972         isec = ipc_perms->security;
5973
5974         ad.type = LSM_AUDIT_DATA_IPC;
5975         ad.u.ipc_id = ipc_perms->key;
5976
5977         return avc_has_perm(&selinux_state,
5978                             sid, isec->sid, isec->sclass, perms, &ad);
5979 }
5980
5981 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5982 {
5983         return msg_msg_alloc_security(msg);
5984 }
5985
5986 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5987 {
5988         msg_msg_free_security(msg);
5989 }
5990
5991 /* message queue security operations */
5992 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5993 {
5994         struct ipc_security_struct *isec;
5995         struct common_audit_data ad;
5996         u32 sid = current_sid();
5997         int rc;
5998
5999         rc = ipc_alloc_security(msq, SECCLASS_MSGQ);
6000         if (rc)
6001                 return rc;
6002
6003         isec = msq->security;
6004
6005         ad.type = LSM_AUDIT_DATA_IPC;
6006         ad.u.ipc_id = msq->key;
6007
6008         rc = avc_has_perm(&selinux_state,
6009                           sid, isec->sid, SECCLASS_MSGQ,
6010                           MSGQ__CREATE, &ad);
6011         if (rc) {
6012                 ipc_free_security(msq);
6013                 return rc;
6014         }
6015         return 0;
6016 }
6017
6018 static void selinux_msg_queue_free_security(struct kern_ipc_perm *msq)
6019 {
6020         ipc_free_security(msq);
6021 }
6022
6023 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6024 {
6025         struct ipc_security_struct *isec;
6026         struct common_audit_data ad;
6027         u32 sid = current_sid();
6028
6029         isec = msq->security;
6030
6031         ad.type = LSM_AUDIT_DATA_IPC;
6032         ad.u.ipc_id = msq->key;
6033
6034         return avc_has_perm(&selinux_state,
6035                             sid, isec->sid, SECCLASS_MSGQ,
6036                             MSGQ__ASSOCIATE, &ad);
6037 }
6038
6039 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6040 {
6041         int err;
6042         int perms;
6043
6044         switch (cmd) {
6045         case IPC_INFO:
6046         case MSG_INFO:
6047                 /* No specific object, just general system-wide information. */
6048                 return avc_has_perm(&selinux_state,
6049                                     current_sid(), SECINITSID_KERNEL,
6050                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6051         case IPC_STAT:
6052         case MSG_STAT:
6053         case MSG_STAT_ANY:
6054                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6055                 break;
6056         case IPC_SET:
6057                 perms = MSGQ__SETATTR;
6058                 break;
6059         case IPC_RMID:
6060                 perms = MSGQ__DESTROY;
6061                 break;
6062         default:
6063                 return 0;
6064         }
6065
6066         err = ipc_has_perm(msq, perms);
6067         return err;
6068 }
6069
6070 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6071 {
6072         struct ipc_security_struct *isec;
6073         struct msg_security_struct *msec;
6074         struct common_audit_data ad;
6075         u32 sid = current_sid();
6076         int rc;
6077
6078         isec = msq->security;
6079         msec = msg->security;
6080
6081         /*
6082          * First time through, need to assign label to the message
6083          */
6084         if (msec->sid == SECINITSID_UNLABELED) {
6085                 /*
6086                  * Compute new sid based on current process and
6087                  * message queue this message will be stored in
6088                  */
6089                 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6090                                              SECCLASS_MSG, NULL, &msec->sid);
6091                 if (rc)
6092                         return rc;
6093         }
6094
6095         ad.type = LSM_AUDIT_DATA_IPC;
6096         ad.u.ipc_id = msq->key;
6097
6098         /* Can this process write to the queue? */
6099         rc = avc_has_perm(&selinux_state,
6100                           sid, isec->sid, SECCLASS_MSGQ,
6101                           MSGQ__WRITE, &ad);
6102         if (!rc)
6103                 /* Can this process send the message */
6104                 rc = avc_has_perm(&selinux_state,
6105                                   sid, msec->sid, SECCLASS_MSG,
6106                                   MSG__SEND, &ad);
6107         if (!rc)
6108                 /* Can the message be put in the queue? */
6109                 rc = avc_has_perm(&selinux_state,
6110                                   msec->sid, isec->sid, SECCLASS_MSGQ,
6111                                   MSGQ__ENQUEUE, &ad);
6112
6113         return rc;
6114 }
6115
6116 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6117                                     struct task_struct *target,
6118                                     long type, int mode)
6119 {
6120         struct ipc_security_struct *isec;
6121         struct msg_security_struct *msec;
6122         struct common_audit_data ad;
6123         u32 sid = task_sid(target);
6124         int rc;
6125
6126         isec = msq->security;
6127         msec = msg->security;
6128
6129         ad.type = LSM_AUDIT_DATA_IPC;
6130         ad.u.ipc_id = msq->key;
6131
6132         rc = avc_has_perm(&selinux_state,
6133                           sid, isec->sid,
6134                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6135         if (!rc)
6136                 rc = avc_has_perm(&selinux_state,
6137                                   sid, msec->sid,
6138                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6139         return rc;
6140 }
6141
6142 /* Shared Memory security operations */
6143 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6144 {
6145         struct ipc_security_struct *isec;
6146         struct common_audit_data ad;
6147         u32 sid = current_sid();
6148         int rc;
6149
6150         rc = ipc_alloc_security(shp, SECCLASS_SHM);
6151         if (rc)
6152                 return rc;
6153
6154         isec = shp->security;
6155
6156         ad.type = LSM_AUDIT_DATA_IPC;
6157         ad.u.ipc_id = shp->key;
6158
6159         rc = avc_has_perm(&selinux_state,
6160                           sid, isec->sid, SECCLASS_SHM,
6161                           SHM__CREATE, &ad);
6162         if (rc) {
6163                 ipc_free_security(shp);
6164                 return rc;
6165         }
6166         return 0;
6167 }
6168
6169 static void selinux_shm_free_security(struct kern_ipc_perm *shp)
6170 {
6171         ipc_free_security(shp);
6172 }
6173
6174 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6175 {
6176         struct ipc_security_struct *isec;
6177         struct common_audit_data ad;
6178         u32 sid = current_sid();
6179
6180         isec = shp->security;
6181
6182         ad.type = LSM_AUDIT_DATA_IPC;
6183         ad.u.ipc_id = shp->key;
6184
6185         return avc_has_perm(&selinux_state,
6186                             sid, isec->sid, SECCLASS_SHM,
6187                             SHM__ASSOCIATE, &ad);
6188 }
6189
6190 /* Note, at this point, shp is locked down */
6191 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6192 {
6193         int perms;
6194         int err;
6195
6196         switch (cmd) {
6197         case IPC_INFO:
6198         case SHM_INFO:
6199                 /* No specific object, just general system-wide information. */
6200                 return avc_has_perm(&selinux_state,
6201                                     current_sid(), SECINITSID_KERNEL,
6202                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6203         case IPC_STAT:
6204         case SHM_STAT:
6205         case SHM_STAT_ANY:
6206                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6207                 break;
6208         case IPC_SET:
6209                 perms = SHM__SETATTR;
6210                 break;
6211         case SHM_LOCK:
6212         case SHM_UNLOCK:
6213                 perms = SHM__LOCK;
6214                 break;
6215         case IPC_RMID:
6216                 perms = SHM__DESTROY;
6217                 break;
6218         default:
6219                 return 0;
6220         }
6221
6222         err = ipc_has_perm(shp, perms);
6223         return err;
6224 }
6225
6226 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6227                              char __user *shmaddr, int shmflg)
6228 {
6229         u32 perms;
6230
6231         if (shmflg & SHM_RDONLY)
6232                 perms = SHM__READ;
6233         else
6234                 perms = SHM__READ | SHM__WRITE;
6235
6236         return ipc_has_perm(shp, perms);
6237 }
6238
6239 /* Semaphore security operations */
6240 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6241 {
6242         struct ipc_security_struct *isec;
6243         struct common_audit_data ad;
6244         u32 sid = current_sid();
6245         int rc;
6246
6247         rc = ipc_alloc_security(sma, SECCLASS_SEM);
6248         if (rc)
6249                 return rc;
6250
6251         isec = sma->security;
6252
6253         ad.type = LSM_AUDIT_DATA_IPC;
6254         ad.u.ipc_id = sma->key;
6255
6256         rc = avc_has_perm(&selinux_state,
6257                           sid, isec->sid, SECCLASS_SEM,
6258                           SEM__CREATE, &ad);
6259         if (rc) {
6260                 ipc_free_security(sma);
6261                 return rc;
6262         }
6263         return 0;
6264 }
6265
6266 static void selinux_sem_free_security(struct kern_ipc_perm *sma)
6267 {
6268         ipc_free_security(sma);
6269 }
6270
6271 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6272 {
6273         struct ipc_security_struct *isec;
6274         struct common_audit_data ad;
6275         u32 sid = current_sid();
6276
6277         isec = sma->security;
6278
6279         ad.type = LSM_AUDIT_DATA_IPC;
6280         ad.u.ipc_id = sma->key;
6281
6282         return avc_has_perm(&selinux_state,
6283                             sid, isec->sid, SECCLASS_SEM,
6284                             SEM__ASSOCIATE, &ad);
6285 }
6286
6287 /* Note, at this point, sma is locked down */
6288 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6289 {
6290         int err;
6291         u32 perms;
6292
6293         switch (cmd) {
6294         case IPC_INFO:
6295         case SEM_INFO:
6296                 /* No specific object, just general system-wide information. */
6297                 return avc_has_perm(&selinux_state,
6298                                     current_sid(), SECINITSID_KERNEL,
6299                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6300         case GETPID:
6301         case GETNCNT:
6302         case GETZCNT:
6303                 perms = SEM__GETATTR;
6304                 break;
6305         case GETVAL:
6306         case GETALL:
6307                 perms = SEM__READ;
6308                 break;
6309         case SETVAL:
6310         case SETALL:
6311                 perms = SEM__WRITE;
6312                 break;
6313         case IPC_RMID:
6314                 perms = SEM__DESTROY;
6315                 break;
6316         case IPC_SET:
6317                 perms = SEM__SETATTR;
6318                 break;
6319         case IPC_STAT:
6320         case SEM_STAT:
6321         case SEM_STAT_ANY:
6322                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6323                 break;
6324         default:
6325                 return 0;
6326         }
6327
6328         err = ipc_has_perm(sma, perms);
6329         return err;
6330 }
6331
6332 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6333                              struct sembuf *sops, unsigned nsops, int alter)
6334 {
6335         u32 perms;
6336
6337         if (alter)
6338                 perms = SEM__READ | SEM__WRITE;
6339         else
6340                 perms = SEM__READ;
6341
6342         return ipc_has_perm(sma, perms);
6343 }
6344
6345 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6346 {
6347         u32 av = 0;
6348
6349         av = 0;
6350         if (flag & S_IRUGO)
6351                 av |= IPC__UNIX_READ;
6352         if (flag & S_IWUGO)
6353                 av |= IPC__UNIX_WRITE;
6354
6355         if (av == 0)
6356                 return 0;
6357
6358         return ipc_has_perm(ipcp, av);
6359 }
6360
6361 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6362 {
6363         struct ipc_security_struct *isec = ipcp->security;
6364         *secid = isec->sid;
6365 }
6366
6367 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6368 {
6369         if (inode)
6370                 inode_doinit_with_dentry(inode, dentry);
6371 }
6372
6373 static int selinux_getprocattr(struct task_struct *p,
6374                                char *name, char **value)
6375 {
6376         const struct task_security_struct *__tsec;
6377         u32 sid;
6378         int error;
6379         unsigned len;
6380
6381         rcu_read_lock();
6382         __tsec = __task_cred(p)->security;
6383
6384         if (current != p) {
6385                 error = avc_has_perm(&selinux_state,
6386                                      current_sid(), __tsec->sid,
6387                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6388                 if (error)
6389                         goto bad;
6390         }
6391
6392         if (!strcmp(name, "current"))
6393                 sid = __tsec->sid;
6394         else if (!strcmp(name, "prev"))
6395                 sid = __tsec->osid;
6396         else if (!strcmp(name, "exec"))
6397                 sid = __tsec->exec_sid;
6398         else if (!strcmp(name, "fscreate"))
6399                 sid = __tsec->create_sid;
6400         else if (!strcmp(name, "keycreate"))
6401                 sid = __tsec->keycreate_sid;
6402         else if (!strcmp(name, "sockcreate"))
6403                 sid = __tsec->sockcreate_sid;
6404         else {
6405                 error = -EINVAL;
6406                 goto bad;
6407         }
6408         rcu_read_unlock();
6409
6410         if (!sid)
6411                 return 0;
6412
6413         error = security_sid_to_context(&selinux_state, sid, value, &len);
6414         if (error)
6415                 return error;
6416         return len;
6417
6418 bad:
6419         rcu_read_unlock();
6420         return error;
6421 }
6422
6423 static int selinux_setprocattr(const char *name, void *value, size_t size)
6424 {
6425         struct task_security_struct *tsec;
6426         struct cred *new;
6427         u32 mysid = current_sid(), sid = 0, ptsid;
6428         int error;
6429         char *str = value;
6430
6431         /*
6432          * Basic control over ability to set these attributes at all.
6433          */
6434         if (!strcmp(name, "exec"))
6435                 error = avc_has_perm(&selinux_state,
6436                                      mysid, mysid, SECCLASS_PROCESS,
6437                                      PROCESS__SETEXEC, NULL);
6438         else if (!strcmp(name, "fscreate"))
6439                 error = avc_has_perm(&selinux_state,
6440                                      mysid, mysid, SECCLASS_PROCESS,
6441                                      PROCESS__SETFSCREATE, NULL);
6442         else if (!strcmp(name, "keycreate"))
6443                 error = avc_has_perm(&selinux_state,
6444                                      mysid, mysid, SECCLASS_PROCESS,
6445                                      PROCESS__SETKEYCREATE, NULL);
6446         else if (!strcmp(name, "sockcreate"))
6447                 error = avc_has_perm(&selinux_state,
6448                                      mysid, mysid, SECCLASS_PROCESS,
6449                                      PROCESS__SETSOCKCREATE, NULL);
6450         else if (!strcmp(name, "current"))
6451                 error = avc_has_perm(&selinux_state,
6452                                      mysid, mysid, SECCLASS_PROCESS,
6453                                      PROCESS__SETCURRENT, NULL);
6454         else
6455                 error = -EINVAL;
6456         if (error)
6457                 return error;
6458
6459         /* Obtain a SID for the context, if one was specified. */
6460         if (size && str[0] && str[0] != '\n') {
6461                 if (str[size-1] == '\n') {
6462                         str[size-1] = 0;
6463                         size--;
6464                 }
6465                 error = security_context_to_sid(&selinux_state, value, size,
6466                                                 &sid, GFP_KERNEL);
6467                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6468                         if (!has_cap_mac_admin(true)) {
6469                                 struct audit_buffer *ab;
6470                                 size_t audit_size;
6471
6472                                 /* We strip a nul only if it is at the end, otherwise the
6473                                  * context contains a nul and we should audit that */
6474                                 if (str[size - 1] == '\0')
6475                                         audit_size = size - 1;
6476                                 else
6477                                         audit_size = size;
6478                                 ab = audit_log_start(audit_context(),
6479                                                      GFP_ATOMIC,
6480                                                      AUDIT_SELINUX_ERR);
6481                                 audit_log_format(ab, "op=fscreate invalid_context=");
6482                                 audit_log_n_untrustedstring(ab, value, audit_size);
6483                                 audit_log_end(ab);
6484
6485                                 return error;
6486                         }
6487                         error = security_context_to_sid_force(
6488                                                       &selinux_state,
6489                                                       value, size, &sid);
6490                 }
6491                 if (error)
6492                         return error;
6493         }
6494
6495         new = prepare_creds();
6496         if (!new)
6497                 return -ENOMEM;
6498
6499         /* Permission checking based on the specified context is
6500            performed during the actual operation (execve,
6501            open/mkdir/...), when we know the full context of the
6502            operation.  See selinux_bprm_set_creds for the execve
6503            checks and may_create for the file creation checks. The
6504            operation will then fail if the context is not permitted. */
6505         tsec = new->security;
6506         if (!strcmp(name, "exec")) {
6507                 tsec->exec_sid = sid;
6508         } else if (!strcmp(name, "fscreate")) {
6509                 tsec->create_sid = sid;
6510         } else if (!strcmp(name, "keycreate")) {
6511                 error = avc_has_perm(&selinux_state,
6512                                      mysid, sid, SECCLASS_KEY, KEY__CREATE,
6513                                      NULL);
6514                 if (error)
6515                         goto abort_change;
6516                 tsec->keycreate_sid = sid;
6517         } else if (!strcmp(name, "sockcreate")) {
6518                 tsec->sockcreate_sid = sid;
6519         } else if (!strcmp(name, "current")) {
6520                 error = -EINVAL;
6521                 if (sid == 0)
6522                         goto abort_change;
6523
6524                 /* Only allow single threaded processes to change context */
6525                 error = -EPERM;
6526                 if (!current_is_single_threaded()) {
6527                         error = security_bounded_transition(&selinux_state,
6528                                                             tsec->sid, sid);
6529                         if (error)
6530                                 goto abort_change;
6531                 }
6532
6533                 /* Check permissions for the transition. */
6534                 error = avc_has_perm(&selinux_state,
6535                                      tsec->sid, sid, SECCLASS_PROCESS,
6536                                      PROCESS__DYNTRANSITION, NULL);
6537                 if (error)
6538                         goto abort_change;
6539
6540                 /* Check for ptracing, and update the task SID if ok.
6541                    Otherwise, leave SID unchanged and fail. */
6542                 ptsid = ptrace_parent_sid();
6543                 if (ptsid != 0) {
6544                         error = avc_has_perm(&selinux_state,
6545                                              ptsid, sid, SECCLASS_PROCESS,
6546                                              PROCESS__PTRACE, NULL);
6547                         if (error)
6548                                 goto abort_change;
6549                 }
6550
6551                 tsec->sid = sid;
6552         } else {
6553                 error = -EINVAL;
6554                 goto abort_change;
6555         }
6556
6557         commit_creds(new);
6558         return size;
6559
6560 abort_change:
6561         abort_creds(new);
6562         return error;
6563 }
6564
6565 static int selinux_ismaclabel(const char *name)
6566 {
6567         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6568 }
6569
6570 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6571 {
6572         return security_sid_to_context(&selinux_state, secid,
6573                                        secdata, seclen);
6574 }
6575
6576 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6577 {
6578         return security_context_to_sid(&selinux_state, secdata, seclen,
6579                                        secid, GFP_KERNEL);
6580 }
6581
6582 static void selinux_release_secctx(char *secdata, u32 seclen)
6583 {
6584         kfree(secdata);
6585 }
6586
6587 static void selinux_inode_invalidate_secctx(struct inode *inode)
6588 {
6589         struct inode_security_struct *isec = inode->i_security;
6590
6591         spin_lock(&isec->lock);
6592         isec->initialized = LABEL_INVALID;
6593         spin_unlock(&isec->lock);
6594 }
6595
6596 /*
6597  *      called with inode->i_mutex locked
6598  */
6599 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6600 {
6601         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6602 }
6603
6604 /*
6605  *      called with inode->i_mutex locked
6606  */
6607 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6608 {
6609         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6610 }
6611
6612 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6613 {
6614         int len = 0;
6615         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6616                                                 ctx, true);
6617         if (len < 0)
6618                 return len;
6619         *ctxlen = len;
6620         return 0;
6621 }
6622 #ifdef CONFIG_KEYS
6623
6624 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6625                              unsigned long flags)
6626 {
6627         const struct task_security_struct *tsec;
6628         struct key_security_struct *ksec;
6629
6630         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6631         if (!ksec)
6632                 return -ENOMEM;
6633
6634         tsec = cred->security;
6635         if (tsec->keycreate_sid)
6636                 ksec->sid = tsec->keycreate_sid;
6637         else
6638                 ksec->sid = tsec->sid;
6639
6640         k->security = ksec;
6641         return 0;
6642 }
6643
6644 static void selinux_key_free(struct key *k)
6645 {
6646         struct key_security_struct *ksec = k->security;
6647
6648         k->security = NULL;
6649         kfree(ksec);
6650 }
6651
6652 static int selinux_key_permission(key_ref_t key_ref,
6653                                   const struct cred *cred,
6654                                   unsigned perm)
6655 {
6656         struct key *key;
6657         struct key_security_struct *ksec;
6658         u32 sid;
6659
6660         /* if no specific permissions are requested, we skip the
6661            permission check. No serious, additional covert channels
6662            appear to be created. */
6663         if (perm == 0)
6664                 return 0;
6665
6666         sid = cred_sid(cred);
6667
6668         key = key_ref_to_ptr(key_ref);
6669         ksec = key->security;
6670
6671         return avc_has_perm(&selinux_state,
6672                             sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6673 }
6674
6675 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6676 {
6677         struct key_security_struct *ksec = key->security;
6678         char *context = NULL;
6679         unsigned len;
6680         int rc;
6681
6682         rc = security_sid_to_context(&selinux_state, ksec->sid,
6683                                      &context, &len);
6684         if (!rc)
6685                 rc = len;
6686         *_buffer = context;
6687         return rc;
6688 }
6689 #endif
6690
6691 #ifdef CONFIG_SECURITY_INFINIBAND
6692 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6693 {
6694         struct common_audit_data ad;
6695         int err;
6696         u32 sid = 0;
6697         struct ib_security_struct *sec = ib_sec;
6698         struct lsm_ibpkey_audit ibpkey;
6699
6700         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6701         if (err)
6702                 return err;
6703
6704         ad.type = LSM_AUDIT_DATA_IBPKEY;
6705         ibpkey.subnet_prefix = subnet_prefix;
6706         ibpkey.pkey = pkey_val;
6707         ad.u.ibpkey = &ibpkey;
6708         return avc_has_perm(&selinux_state,
6709                             sec->sid, sid,
6710                             SECCLASS_INFINIBAND_PKEY,
6711                             INFINIBAND_PKEY__ACCESS, &ad);
6712 }
6713
6714 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6715                                             u8 port_num)
6716 {
6717         struct common_audit_data ad;
6718         int err;
6719         u32 sid = 0;
6720         struct ib_security_struct *sec = ib_sec;
6721         struct lsm_ibendport_audit ibendport;
6722
6723         err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6724                                       &sid);
6725
6726         if (err)
6727                 return err;
6728
6729         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6730         strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6731         ibendport.port = port_num;
6732         ad.u.ibendport = &ibendport;
6733         return avc_has_perm(&selinux_state,
6734                             sec->sid, sid,
6735                             SECCLASS_INFINIBAND_ENDPORT,
6736                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6737 }
6738
6739 static int selinux_ib_alloc_security(void **ib_sec)
6740 {
6741         struct ib_security_struct *sec;
6742
6743         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6744         if (!sec)
6745                 return -ENOMEM;
6746         sec->sid = current_sid();
6747
6748         *ib_sec = sec;
6749         return 0;
6750 }
6751
6752 static void selinux_ib_free_security(void *ib_sec)
6753 {
6754         kfree(ib_sec);
6755 }
6756 #endif
6757
6758 #ifdef CONFIG_BPF_SYSCALL
6759 static int selinux_bpf(int cmd, union bpf_attr *attr,
6760                                      unsigned int size)
6761 {
6762         u32 sid = current_sid();
6763         int ret;
6764
6765         switch (cmd) {
6766         case BPF_MAP_CREATE:
6767                 ret = avc_has_perm(&selinux_state,
6768                                    sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6769                                    NULL);
6770                 break;
6771         case BPF_PROG_LOAD:
6772                 ret = avc_has_perm(&selinux_state,
6773                                    sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6774                                    NULL);
6775                 break;
6776         default:
6777                 ret = 0;
6778                 break;
6779         }
6780
6781         return ret;
6782 }
6783
6784 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6785 {
6786         u32 av = 0;
6787
6788         if (fmode & FMODE_READ)
6789                 av |= BPF__MAP_READ;
6790         if (fmode & FMODE_WRITE)
6791                 av |= BPF__MAP_WRITE;
6792         return av;
6793 }
6794
6795 /* This function will check the file pass through unix socket or binder to see
6796  * if it is a bpf related object. And apply correspinding checks on the bpf
6797  * object based on the type. The bpf maps and programs, not like other files and
6798  * socket, are using a shared anonymous inode inside the kernel as their inode.
6799  * So checking that inode cannot identify if the process have privilege to
6800  * access the bpf object and that's why we have to add this additional check in
6801  * selinux_file_receive and selinux_binder_transfer_files.
6802  */
6803 static int bpf_fd_pass(struct file *file, u32 sid)
6804 {
6805         struct bpf_security_struct *bpfsec;
6806         struct bpf_prog *prog;
6807         struct bpf_map *map;
6808         int ret;
6809
6810         if (file->f_op == &bpf_map_fops) {
6811                 map = file->private_data;
6812                 bpfsec = map->security;
6813                 ret = avc_has_perm(&selinux_state,
6814                                    sid, bpfsec->sid, SECCLASS_BPF,
6815                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6816                 if (ret)
6817                         return ret;
6818         } else if (file->f_op == &bpf_prog_fops) {
6819                 prog = file->private_data;
6820                 bpfsec = prog->aux->security;
6821                 ret = avc_has_perm(&selinux_state,
6822                                    sid, bpfsec->sid, SECCLASS_BPF,
6823                                    BPF__PROG_RUN, NULL);
6824                 if (ret)
6825                         return ret;
6826         }
6827         return 0;
6828 }
6829
6830 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6831 {
6832         u32 sid = current_sid();
6833         struct bpf_security_struct *bpfsec;
6834
6835         bpfsec = map->security;
6836         return avc_has_perm(&selinux_state,
6837                             sid, bpfsec->sid, SECCLASS_BPF,
6838                             bpf_map_fmode_to_av(fmode), NULL);
6839 }
6840
6841 static int selinux_bpf_prog(struct bpf_prog *prog)
6842 {
6843         u32 sid = current_sid();
6844         struct bpf_security_struct *bpfsec;
6845
6846         bpfsec = prog->aux->security;
6847         return avc_has_perm(&selinux_state,
6848                             sid, bpfsec->sid, SECCLASS_BPF,
6849                             BPF__PROG_RUN, NULL);
6850 }
6851
6852 static int selinux_bpf_map_alloc(struct bpf_map *map)
6853 {
6854         struct bpf_security_struct *bpfsec;
6855
6856         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6857         if (!bpfsec)
6858                 return -ENOMEM;
6859
6860         bpfsec->sid = current_sid();
6861         map->security = bpfsec;
6862
6863         return 0;
6864 }
6865
6866 static void selinux_bpf_map_free(struct bpf_map *map)
6867 {
6868         struct bpf_security_struct *bpfsec = map->security;
6869
6870         map->security = NULL;
6871         kfree(bpfsec);
6872 }
6873
6874 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6875 {
6876         struct bpf_security_struct *bpfsec;
6877
6878         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6879         if (!bpfsec)
6880                 return -ENOMEM;
6881
6882         bpfsec->sid = current_sid();
6883         aux->security = bpfsec;
6884
6885         return 0;
6886 }
6887
6888 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6889 {
6890         struct bpf_security_struct *bpfsec = aux->security;
6891
6892         aux->security = NULL;
6893         kfree(bpfsec);
6894 }
6895 #endif
6896
6897 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6898         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6899         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6900         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6901         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6902
6903         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6904         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6905         LSM_HOOK_INIT(capget, selinux_capget),
6906         LSM_HOOK_INIT(capset, selinux_capset),
6907         LSM_HOOK_INIT(capable, selinux_capable),
6908         LSM_HOOK_INIT(quotactl, selinux_quotactl),
6909         LSM_HOOK_INIT(quota_on, selinux_quota_on),
6910         LSM_HOOK_INIT(syslog, selinux_syslog),
6911         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6912
6913         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6914
6915         LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6916         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6917         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6918
6919         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6920         LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6921         LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
6922         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6923         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6924         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6925         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6926         LSM_HOOK_INIT(sb_mount, selinux_mount),
6927         LSM_HOOK_INIT(sb_umount, selinux_umount),
6928         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6929         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6930         LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
6931
6932         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6933         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6934
6935         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6936         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6937         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6938         LSM_HOOK_INIT(inode_create, selinux_inode_create),
6939         LSM_HOOK_INIT(inode_link, selinux_inode_link),
6940         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6941         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6942         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6943         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6944         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6945         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6946         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6947         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6948         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6949         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6950         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6951         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6952         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6953         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6954         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6955         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6956         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6957         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6958         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6959         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6960         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6961         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6962
6963         LSM_HOOK_INIT(file_permission, selinux_file_permission),
6964         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6965         LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6966         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6967         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6968         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6969         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6970         LSM_HOOK_INIT(file_lock, selinux_file_lock),
6971         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6972         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6973         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6974         LSM_HOOK_INIT(file_receive, selinux_file_receive),
6975
6976         LSM_HOOK_INIT(file_open, selinux_file_open),
6977
6978         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6979         LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6980         LSM_HOOK_INIT(cred_free, selinux_cred_free),
6981         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6982         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6983         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
6984         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6985         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6986         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6987         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
6988         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6989         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6990         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6991         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6992         LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6993         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6994         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6995         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6996         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6997         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6998         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6999         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7000         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7001         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7002         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7003
7004         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7005         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7006
7007         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7008         LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
7009
7010         LSM_HOOK_INIT(msg_queue_alloc_security,
7011                         selinux_msg_queue_alloc_security),
7012         LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
7013         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7014         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7015         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7016         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7017
7018         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7019         LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
7020         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7021         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7022         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7023
7024         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7025         LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
7026         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7027         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7028         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7029
7030         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7031
7032         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7033         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7034
7035         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7036         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7037         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7038         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7039         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7040         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7041         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7042         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7043
7044         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7045         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7046
7047         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7048         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7049         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7050         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7051         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7052         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7053         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7054         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7055         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7056         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7057         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7058         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7059         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7060         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7061         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7062         LSM_HOOK_INIT(socket_getpeersec_stream,
7063                         selinux_socket_getpeersec_stream),
7064         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7065         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7066         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7067         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7068         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7069         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7070         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7071         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7072         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7073         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7074         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7075         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7076         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7077         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7078         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7079         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7080         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7081         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7082         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7083         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7084         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7085         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7086 #ifdef CONFIG_SECURITY_INFINIBAND
7087         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7088         LSM_HOOK_INIT(ib_endport_manage_subnet,
7089                       selinux_ib_endport_manage_subnet),
7090         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7091         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7092 #endif
7093 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7094         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7095         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7096         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7097         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7098         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7099         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7100                         selinux_xfrm_state_alloc_acquire),
7101         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7102         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7103         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7104         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7105                         selinux_xfrm_state_pol_flow_match),
7106         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7107 #endif
7108
7109 #ifdef CONFIG_KEYS
7110         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7111         LSM_HOOK_INIT(key_free, selinux_key_free),
7112         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7113         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7114 #endif
7115
7116 #ifdef CONFIG_AUDIT
7117         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7118         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7119         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7120         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7121 #endif
7122
7123 #ifdef CONFIG_BPF_SYSCALL
7124         LSM_HOOK_INIT(bpf, selinux_bpf),
7125         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7126         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7127         LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7128         LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7129         LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7130         LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7131 #endif
7132 };
7133
7134 static __init int selinux_init(void)
7135 {
7136         if (!security_module_enable("selinux")) {
7137                 selinux_enabled = 0;
7138                 return 0;
7139         }
7140
7141         if (!selinux_enabled) {
7142                 pr_info("SELinux:  Disabled at boot.\n");
7143                 return 0;
7144         }
7145
7146         pr_info("SELinux:  Initializing.\n");
7147
7148         memset(&selinux_state, 0, sizeof(selinux_state));
7149         enforcing_set(&selinux_state, selinux_enforcing_boot);
7150         selinux_state.checkreqprot = selinux_checkreqprot_boot;
7151         selinux_ss_init(&selinux_state.ss);
7152         selinux_avc_init(&selinux_state.avc);
7153
7154         /* Set the security state for the initial task. */
7155         cred_init_security();
7156
7157         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7158
7159         sel_inode_cache = kmem_cache_create("selinux_inode_security",
7160                                             sizeof(struct inode_security_struct),
7161                                             0, SLAB_PANIC, NULL);
7162         file_security_cache = kmem_cache_create("selinux_file_security",
7163                                             sizeof(struct file_security_struct),
7164                                             0, SLAB_PANIC, NULL);
7165         avc_init();
7166
7167         avtab_cache_init();
7168
7169         ebitmap_cache_init();
7170
7171         hashtab_cache_init();
7172
7173         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7174
7175         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7176                 panic("SELinux: Unable to register AVC netcache callback\n");
7177
7178         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7179                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7180
7181         if (selinux_enforcing_boot)
7182                 pr_debug("SELinux:  Starting in enforcing mode\n");
7183         else
7184                 pr_debug("SELinux:  Starting in permissive mode\n");
7185
7186         return 0;
7187 }
7188
7189 static void delayed_superblock_init(struct super_block *sb, void *unused)
7190 {
7191         superblock_doinit(sb, NULL);
7192 }
7193
7194 void selinux_complete_init(void)
7195 {
7196         pr_debug("SELinux:  Completing initialization.\n");
7197
7198         /* Set up any superblocks initialized prior to the policy load. */
7199         pr_debug("SELinux:  Setting up existing superblocks.\n");
7200         iterate_supers(delayed_superblock_init, NULL);
7201 }
7202
7203 /* SELinux requires early initialization in order to label
7204    all processes and objects when they are created. */
7205 security_initcall(selinux_init);
7206
7207 #if defined(CONFIG_NETFILTER)
7208
7209 static const struct nf_hook_ops selinux_nf_ops[] = {
7210         {
7211                 .hook =         selinux_ipv4_postroute,
7212                 .pf =           NFPROTO_IPV4,
7213                 .hooknum =      NF_INET_POST_ROUTING,
7214                 .priority =     NF_IP_PRI_SELINUX_LAST,
7215         },
7216         {
7217                 .hook =         selinux_ipv4_forward,
7218                 .pf =           NFPROTO_IPV4,
7219                 .hooknum =      NF_INET_FORWARD,
7220                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7221         },
7222         {
7223                 .hook =         selinux_ipv4_output,
7224                 .pf =           NFPROTO_IPV4,
7225                 .hooknum =      NF_INET_LOCAL_OUT,
7226                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7227         },
7228 #if IS_ENABLED(CONFIG_IPV6)
7229         {
7230                 .hook =         selinux_ipv6_postroute,
7231                 .pf =           NFPROTO_IPV6,
7232                 .hooknum =      NF_INET_POST_ROUTING,
7233                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7234         },
7235         {
7236                 .hook =         selinux_ipv6_forward,
7237                 .pf =           NFPROTO_IPV6,
7238                 .hooknum =      NF_INET_FORWARD,
7239                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7240         },
7241         {
7242                 .hook =         selinux_ipv6_output,
7243                 .pf =           NFPROTO_IPV6,
7244                 .hooknum =      NF_INET_LOCAL_OUT,
7245                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7246         },
7247 #endif  /* IPV6 */
7248 };
7249
7250 static int __net_init selinux_nf_register(struct net *net)
7251 {
7252         return nf_register_net_hooks(net, selinux_nf_ops,
7253                                      ARRAY_SIZE(selinux_nf_ops));
7254 }
7255
7256 static void __net_exit selinux_nf_unregister(struct net *net)
7257 {
7258         nf_unregister_net_hooks(net, selinux_nf_ops,
7259                                 ARRAY_SIZE(selinux_nf_ops));
7260 }
7261
7262 static struct pernet_operations selinux_net_ops = {
7263         .init = selinux_nf_register,
7264         .exit = selinux_nf_unregister,
7265 };
7266
7267 static int __init selinux_nf_ip_init(void)
7268 {
7269         int err;
7270
7271         if (!selinux_enabled)
7272                 return 0;
7273
7274         pr_debug("SELinux:  Registering netfilter hooks\n");
7275
7276         err = register_pernet_subsys(&selinux_net_ops);
7277         if (err)
7278                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7279
7280         return 0;
7281 }
7282 __initcall(selinux_nf_ip_init);
7283
7284 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7285 static void selinux_nf_ip_exit(void)
7286 {
7287         pr_debug("SELinux:  Unregistering netfilter hooks\n");
7288
7289         unregister_pernet_subsys(&selinux_net_ops);
7290 }
7291 #endif
7292
7293 #else /* CONFIG_NETFILTER */
7294
7295 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7296 #define selinux_nf_ip_exit()
7297 #endif
7298
7299 #endif /* CONFIG_NETFILTER */
7300
7301 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7302 int selinux_disable(struct selinux_state *state)
7303 {
7304         if (state->initialized) {
7305                 /* Not permitted after initial policy load. */
7306                 return -EINVAL;
7307         }
7308
7309         if (state->disabled) {
7310                 /* Only do this once. */
7311                 return -EINVAL;
7312         }
7313
7314         state->disabled = 1;
7315
7316         pr_info("SELinux:  Disabled at runtime.\n");
7317
7318         selinux_enabled = 0;
7319
7320         security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7321
7322         /* Try to destroy the avc node cache */
7323         avc_disable();
7324
7325         /* Unregister netfilter hooks. */
7326         selinux_nf_ip_exit();
7327
7328         /* Unregister selinuxfs. */
7329         exit_sel_fs();
7330
7331         return 0;
7332 }
7333 #endif