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, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *                                         Eric Paris <eparis@redhat.com>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <dgoeddel@trustedcs.com>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <paul@paul-moore.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kd.h>
  28 #include <linux/kernel.h>
  29 #include <linux/tracehook.h>
  30 #include <linux/errno.h>
  31 #include <linux/sched.h>
  32 #include <linux/security.h>
  33 #include <linux/xattr.h>
  34 #include <linux/capability.h>
  35 #include <linux/unistd.h>
  36 #include <linux/mm.h>
  37 #include <linux/mman.h>
  38 #include <linux/slab.h>
  39 #include <linux/pagemap.h>
  40 #include <linux/proc_fs.h>
  41 #include <linux/swap.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/syscalls.h>
  44 #include <linux/dcache.h>
  45 #include <linux/file.h>
  46 #include <linux/fdtable.h>
  47 #include <linux/namei.h>
  48 #include <linux/mount.h>
  49 #include <linux/netfilter_ipv4.h>
  50 #include <linux/netfilter_ipv6.h>
  51 #include <linux/tty.h>
  52 #include <net/icmp.h>
  53 #include <net/ip.h>             /* for local_port_range[] */
  54 #include <net/sock.h>
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/inet_connection_sock.h>
  57 #include <net/net_namespace.h>
  58 #include <net/netlabel.h>
  59 #include <linux/uaccess.h>
  60 #include <asm/ioctls.h>
  61 #include <linux/atomic.h>
  62 #include <linux/bitops.h>
  63 #include <linux/interrupt.h>
  64 #include <linux/netdevice.h>    /* for network interface checks */
  65 #include <net/netlink.h>
  66 #include <linux/tcp.h>
  67 #include <linux/udp.h>
  68 #include <linux/dccp.h>
  69 #include <linux/quota.h>
  70 #include <linux/un.h>           /* for Unix socket types */
  71 #include <net/af_unix.h>        /* for Unix socket types */
  72 #include <linux/parser.h>
  73 #include <linux/nfs_mount.h>
  74 #include <net/ipv6.h>
  75 #include <linux/hugetlb.h>
  76 #include <linux/personality.h>
  77 #include <linux/audit.h>
  78 #include <linux/string.h>
  79 #include <linux/selinux.h>
  80 #include <linux/mutex.h>
  81 #include <linux/posix-timers.h>
  82 #include <linux/syslog.h>
  83 #include <linux/user_namespace.h>
  84 #include <linux/export.h>
  85 #include <linux/security.h>
  86 #include <linux/msg.h>
  87 #include <linux/shm.h>
  88
  89 #include "avc.h"
  90 #include "objsec.h"
  91 #include "netif.h"
  92 #include "netnode.h"
  93 #include "netport.h"
  94 #include "xfrm.h"
  95 #include "netlabel.h"
  96 #include "audit.h"
  97 #include "avc_ss.h"
  98
  99 #define SB_TYPE_FMT "%s%s%s"
 100 #define SB_SUBTYPE(sb) (sb->s_subtype && sb->s_subtype[0])
 101 #define SB_TYPE_ARGS(sb) sb->s_type->name, SB_SUBTYPE(sb) ? "." : "", SB_SUBTYPE(sb) ? sb->s_subtype : ""
 102
 103 extern struct security_operations *security_ops;
 104
 105 /* SECMARK reference count */
 106 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 107
 108 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 109 int selinux_enforcing;
 110
 111 static int __init enforcing_setup(char *str)
 112 {
 113         unsigned long enforcing;
 114         if (!strict_strtoul(str, 0, &enforcing))
 115                 selinux_enforcing = enforcing ? 1 : 0;
 116         return 1;
 117 }
 118 __setup("enforcing=", enforcing_setup);
 119 #endif
 120
 121 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 122 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 123
 124 static int __init selinux_enabled_setup(char *str)
 125 {
 126         unsigned long enabled;
 127         if (!strict_strtoul(str, 0, &enabled))
 128                 selinux_enabled = enabled ? 1 : 0;
 129         return 1;
 130 }
 131 __setup("selinux=", selinux_enabled_setup);
 132 #else
 133 int selinux_enabled = 1;
 134 #endif
 135
 136 static struct kmem_cache *sel_inode_cache;
 137
 138 /**
 139  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 140  *
 141  * Description:
 142  * This function checks the SECMARK reference counter to see if any SECMARK
 143  * targets are currently configured, if the reference counter is greater than
 144  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 145  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 146  * policy capability is enabled, SECMARK is always considered enabled.
 147  *
 148  */
 149 static int selinux_secmark_enabled(void)
 150 {
 151         return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
 152 }
 153
 154 /**
 155  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 156  *
 157  * Description:
 158  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 159  * (1) if any are enabled or false (0) if neither are enabled.  If the
 160  * always_check_network policy capability is enabled, peer labeling
 161  * is always considered enabled.
 162  *
 163  */
 164 static int selinux_peerlbl_enabled(void)
 165 {
 166         return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
 167 }
 168
 169 /*
 170  * initialise the security for the init task
 171  */
 172 static void cred_init_security(void)
 173 {
 174         struct cred *cred = (struct cred *) current->real_cred;
 175         struct task_security_struct *tsec;
 176
 177         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 178         if (!tsec)
 179                 panic("SELinux:  Failed to initialize initial task.\n");
 180
 181         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 182         cred->security = tsec;
 183 }
 184
 185 /*
 186  * get the security ID of a set of credentials
 187  */
 188 static inline u32 cred_sid(const struct cred *cred)
 189 {
 190         const struct task_security_struct *tsec;
 191
 192         tsec = cred->security;
 193         return tsec->sid;
 194 }
 195
 196 /*
 197  * get the objective security ID of a task
 198  */
 199 static inline u32 task_sid(const struct task_struct *task)
 200 {
 201         u32 sid;
 202
 203         rcu_read_lock();
 204         sid = cred_sid(__task_cred(task));
 205         rcu_read_unlock();
 206         return sid;
 207 }
 208
 209 /*
 210  * get the subjective security ID of the current task
 211  */
 212 static inline u32 current_sid(void)
 213 {
 214         const struct task_security_struct *tsec = current_security();
 215
 216         return tsec->sid;
 217 }
 218
 219 /* Allocate and free functions for each kind of security blob. */
 220
 221 static int inode_alloc_security(struct inode *inode)
 222 {
 223         struct inode_security_struct *isec;
 224         u32 sid = current_sid();
 225
 226         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 227         if (!isec)
 228                 return -ENOMEM;
 229
 230         mutex_init(&isec->lock);
 231         INIT_LIST_HEAD(&isec->list);
 232         isec->inode = inode;
 233         isec->sid = SECINITSID_UNLABELED;
 234         isec->sclass = SECCLASS_FILE;
 235         isec->task_sid = sid;
 236         inode->i_security = isec;
 237
 238         return 0;
 239 }
 240
 241 static void inode_free_security(struct inode *inode)
 242 {
 243         struct inode_security_struct *isec = inode->i_security;
 244         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 245
 246         spin_lock(&sbsec->isec_lock);
 247         if (!list_empty(&isec->list))
 248                 list_del_init(&isec->list);
 249         spin_unlock(&sbsec->isec_lock);
 250
 251         inode->i_security = NULL;
 252         kmem_cache_free(sel_inode_cache, isec);
 253 }
 254
 255 static int file_alloc_security(struct file *file)
 256 {
 257         struct file_security_struct *fsec;
 258         u32 sid = current_sid();
 259
 260         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 261         if (!fsec)
 262                 return -ENOMEM;
 263
 264         fsec->sid = sid;
 265         fsec->fown_sid = sid;
 266         file->f_security = fsec;
 267
 268         return 0;
 269 }
 270
 271 static void file_free_security(struct file *file)
 272 {
 273         struct file_security_struct *fsec = file->f_security;
 274         file->f_security = NULL;
 275         kfree(fsec);
 276 }
 277
 278 static int superblock_alloc_security(struct super_block *sb)
 279 {
 280         struct superblock_security_struct *sbsec;
 281
 282         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 283         if (!sbsec)
 284                 return -ENOMEM;
 285
 286         mutex_init(&sbsec->lock);
 287         INIT_LIST_HEAD(&sbsec->isec_head);
 288         spin_lock_init(&sbsec->isec_lock);
 289         sbsec->sb = sb;
 290         sbsec->sid = SECINITSID_UNLABELED;
 291         sbsec->def_sid = SECINITSID_FILE;
 292         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 293         sb->s_security = sbsec;
 294
 295         return 0;
 296 }
 297
 298 static void superblock_free_security(struct super_block *sb)
 299 {
 300         struct superblock_security_struct *sbsec = sb->s_security;
 301         sb->s_security = NULL;
 302         kfree(sbsec);
 303 }
 304
 305 /* The file system's label must be initialized prior to use. */
 306
 307 static const char *labeling_behaviors[7] = {
 308         "uses xattr",
 309         "uses transition SIDs",
 310         "uses task SIDs",
 311         "uses genfs_contexts",
 312         "not configured for labeling",
 313         "uses mountpoint labeling",
 314         "uses native labeling",
 315 };
 316
 317 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 318
 319 static inline int inode_doinit(struct inode *inode)
 320 {
 321         return inode_doinit_with_dentry(inode, NULL);
 322 }
 323
 324 enum {
 325         Opt_error = -1,
 326         Opt_context = 1,
 327         Opt_fscontext = 2,
 328         Opt_defcontext = 3,
 329         Opt_rootcontext = 4,
 330         Opt_labelsupport = 5,
 331         Opt_nextmntopt = 6,
 332 };
 333
 334 #define NUM_SEL_MNT_OPTS        (Opt_nextmntopt - 1)
 335
 336 static const match_table_t tokens = {
 337         {Opt_context, CONTEXT_STR "%s"},
 338         {Opt_fscontext, FSCONTEXT_STR "%s"},
 339         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 340         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 341         {Opt_labelsupport, LABELSUPP_STR},
 342         {Opt_error, NULL},
 343 };
 344
 345 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 346
 347 static int may_context_mount_sb_relabel(u32 sid,
 348                         struct superblock_security_struct *sbsec,
 349                         const struct cred *cred)
 350 {
 351         const struct task_security_struct *tsec = cred->security;
 352         int rc;
 353
 354         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 355                           FILESYSTEM__RELABELFROM, NULL);
 356         if (rc)
 357                 return rc;
 358
 359         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 360                           FILESYSTEM__RELABELTO, NULL);
 361         return rc;
 362 }
 363
 364 static int may_context_mount_inode_relabel(u32 sid,
 365                         struct superblock_security_struct *sbsec,
 366                         const struct cred *cred)
 367 {
 368         const struct task_security_struct *tsec = cred->security;
 369         int rc;
 370         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 371                           FILESYSTEM__RELABELFROM, NULL);
 372         if (rc)
 373                 return rc;
 374
 375         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 376                           FILESYSTEM__ASSOCIATE, NULL);
 377         return rc;
 378 }
 379
 380 static int selinux_is_sblabel_mnt(struct super_block *sb)
 381 {
 382         struct superblock_security_struct *sbsec = sb->s_security;
 383
 384         if (sbsec->behavior == SECURITY_FS_USE_XATTR ||
 385             sbsec->behavior == SECURITY_FS_USE_TRANS ||
 386             sbsec->behavior == SECURITY_FS_USE_TASK)
 387                 return 1;
 388
 389         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 390         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 391                 return 1;
 392
 393         /*
 394          * Special handling for rootfs. Is genfs but supports
 395          * setting SELinux context on in-core inodes.
 396          */
 397         if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
 398                 return 1;
 399
 400         return 0;
 401 }
 402
 403 static int sb_finish_set_opts(struct super_block *sb)
 404 {
 405         struct superblock_security_struct *sbsec = sb->s_security;
 406         struct dentry *root = sb->s_root;
 407         struct inode *root_inode = root->d_inode;
 408         int rc = 0;
 409
 410         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 411                 /* Make sure that the xattr handler exists and that no
 412                    error other than -ENODATA is returned by getxattr on
 413                    the root directory.  -ENODATA is ok, as this may be
 414                    the first boot of the SELinux kernel before we have
 415                    assigned xattr values to the filesystem. */
 416                 if (!root_inode->i_op->getxattr) {
 417                         printk(KERN_WARNING "SELinux: (dev %s, type "SB_TYPE_FMT") has no "
 418                                "xattr support\n", sb->s_id, SB_TYPE_ARGS(sb));
 419                         rc = -EOPNOTSUPP;
 420                         goto out;
 421                 }
 422                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 423                 if (rc < 0 && rc != -ENODATA) {
 424                         if (rc == -EOPNOTSUPP)
 425                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 426                                        SB_TYPE_FMT") has no security xattr handler\n",
 427                                        sb->s_id, SB_TYPE_ARGS(sb));
 428                         else
 429                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 430                                        SB_TYPE_FMT") getxattr errno %d\n", sb->s_id,
 431                                        SB_TYPE_ARGS(sb), -rc);
 432                         goto out;
 433                 }
 434         }
 435
 436         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 437                 printk(KERN_ERR "SELinux: initialized (dev %s, type "SB_TYPE_FMT"), unknown behavior\n",
 438                        sb->s_id, SB_TYPE_ARGS(sb));
 439         else
 440                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type "SB_TYPE_FMT"), %s\n",
 441                        sb->s_id, SB_TYPE_ARGS(sb),
 442                        labeling_behaviors[sbsec->behavior-1]);
 443
 444         sbsec->flags |= SE_SBINITIALIZED;
 445         if (selinux_is_sblabel_mnt(sb))
 446                 sbsec->flags |= SBLABEL_MNT;
 447
 448         /* Initialize the root inode. */
 449         rc = inode_doinit_with_dentry(root_inode, root);
 450
 451         /* Initialize any other inodes associated with the superblock, e.g.
 452            inodes created prior to initial policy load or inodes created
 453            during get_sb by a pseudo filesystem that directly
 454            populates itself. */
 455         spin_lock(&sbsec->isec_lock);
 456 next_inode:
 457         if (!list_empty(&sbsec->isec_head)) {
 458                 struct inode_security_struct *isec =
 459                                 list_entry(sbsec->isec_head.next,
 460                                            struct inode_security_struct, list);
 461                 struct inode *inode = isec->inode;
 462                 spin_unlock(&sbsec->isec_lock);
 463                 inode = igrab(inode);
 464                 if (inode) {
 465                         if (!IS_PRIVATE(inode))
 466                                 inode_doinit(inode);
 467                         iput(inode);
 468                 }
 469                 spin_lock(&sbsec->isec_lock);
 470                 list_del_init(&isec->list);
 471                 goto next_inode;
 472         }
 473         spin_unlock(&sbsec->isec_lock);
 474 out:
 475         return rc;
 476 }
 477
 478 /*
 479  * This function should allow an FS to ask what it's mount security
 480  * options were so it can use those later for submounts, displaying
 481  * mount options, or whatever.
 482  */
 483 static int selinux_get_mnt_opts(const struct super_block *sb,
 484                                 struct security_mnt_opts *opts)
 485 {
 486         int rc = 0, i;
 487         struct superblock_security_struct *sbsec = sb->s_security;
 488         char *context = NULL;
 489         u32 len;
 490         char tmp;
 491
 492         security_init_mnt_opts(opts);
 493
 494         if (!(sbsec->flags & SE_SBINITIALIZED))
 495                 return -EINVAL;
 496
 497         if (!ss_initialized)
 498                 return -EINVAL;
 499
 500         /* make sure we always check enough bits to cover the mask */
 501         BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
 502
 503         tmp = sbsec->flags & SE_MNTMASK;
 504         /* count the number of mount options for this sb */
 505         for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
 506                 if (tmp & 0x01)
 507                         opts->num_mnt_opts++;
 508                 tmp >>= 1;
 509         }
 510         /* Check if the Label support flag is set */
 511         if (sbsec->flags & SBLABEL_MNT)
 512                 opts->num_mnt_opts++;
 513
 514         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 515         if (!opts->mnt_opts) {
 516                 rc = -ENOMEM;
 517                 goto out_free;
 518         }
 519
 520         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 521         if (!opts->mnt_opts_flags) {
 522                 rc = -ENOMEM;
 523                 goto out_free;
 524         }
 525
 526         i = 0;
 527         if (sbsec->flags & FSCONTEXT_MNT) {
 528                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 529                 if (rc)
 530                         goto out_free;
 531                 opts->mnt_opts[i] = context;
 532                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 533         }
 534         if (sbsec->flags & CONTEXT_MNT) {
 535                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 536                 if (rc)
 537                         goto out_free;
 538                 opts->mnt_opts[i] = context;
 539                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 540         }
 541         if (sbsec->flags & DEFCONTEXT_MNT) {
 542                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 543                 if (rc)
 544                         goto out_free;
 545                 opts->mnt_opts[i] = context;
 546                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 547         }
 548         if (sbsec->flags & ROOTCONTEXT_MNT) {
 549                 struct inode *root = sbsec->sb->s_root->d_inode;
 550                 struct inode_security_struct *isec = root->i_security;
 551
 552                 rc = security_sid_to_context(isec->sid, &context, &len);
 553                 if (rc)
 554                         goto out_free;
 555                 opts->mnt_opts[i] = context;
 556                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 557         }
 558         if (sbsec->flags & SBLABEL_MNT) {
 559                 opts->mnt_opts[i] = NULL;
 560                 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
 561         }
 562
 563         BUG_ON(i != opts->num_mnt_opts);
 564
 565         return 0;
 566
 567 out_free:
 568         security_free_mnt_opts(opts);
 569         return rc;
 570 }
 571
 572 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 573                       u32 old_sid, u32 new_sid)
 574 {
 575         char mnt_flags = sbsec->flags & SE_MNTMASK;
 576
 577         /* check if the old mount command had the same options */
 578         if (sbsec->flags & SE_SBINITIALIZED)
 579                 if (!(sbsec->flags & flag) ||
 580                     (old_sid != new_sid))
 581                         return 1;
 582
 583         /* check if we were passed the same options twice,
 584          * aka someone passed context=a,context=b
 585          */
 586         if (!(sbsec->flags & SE_SBINITIALIZED))
 587                 if (mnt_flags & flag)
 588                         return 1;
 589         return 0;
 590 }
 591
 592 /*
 593  * Allow filesystems with binary mount data to explicitly set mount point
 594  * labeling information.
 595  */
 596 static int selinux_set_mnt_opts(struct super_block *sb,
 597                                 struct security_mnt_opts *opts,
 598                                 unsigned long kern_flags,
 599                                 unsigned long *set_kern_flags)
 600 {
 601         const struct cred *cred = current_cred();
 602         int rc = 0, i;
 603         struct superblock_security_struct *sbsec = sb->s_security;
 604         struct inode *inode = sbsec->sb->s_root->d_inode;
 605         struct inode_security_struct *root_isec = inode->i_security;
 606         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 607         u32 defcontext_sid = 0;
 608         char **mount_options = opts->mnt_opts;
 609         int *flags = opts->mnt_opts_flags;
 610         int num_opts = opts->num_mnt_opts;
 611
 612         mutex_lock(&sbsec->lock);
 613
 614         if (!ss_initialized) {
 615                 if (!num_opts) {
 616                         /* Defer initialization until selinux_complete_init,
 617                            after the initial policy is loaded and the security
 618                            server is ready to handle calls. */
 619                         goto out;
 620                 }
 621                 rc = -EINVAL;
 622                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 623                         "before the security server is initialized\n");
 624                 goto out;
 625         }
 626         if (kern_flags && !set_kern_flags) {
 627                 /* Specifying internal flags without providing a place to
 628                  * place the results is not allowed */
 629                 rc = -EINVAL;
 630                 goto out;
 631         }
 632
 633         /*
 634          * Binary mount data FS will come through this function twice.  Once
 635          * from an explicit call and once from the generic calls from the vfs.
 636          * Since the generic VFS calls will not contain any security mount data
 637          * we need to skip the double mount verification.
 638          *
 639          * This does open a hole in which we will not notice if the first
 640          * mount using this sb set explict options and a second mount using
 641          * this sb does not set any security options.  (The first options
 642          * will be used for both mounts)
 643          */
 644         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 645             && (num_opts == 0))
 646                 goto out;
 647
 648         /*
 649          * parse the mount options, check if they are valid sids.
 650          * also check if someone is trying to mount the same sb more
 651          * than once with different security options.
 652          */
 653         for (i = 0; i < num_opts; i++) {
 654                 u32 sid;
 655
 656                 if (flags[i] == SBLABEL_MNT)
 657                         continue;
 658                 rc = security_context_to_sid(mount_options[i],
 659                                              strlen(mount_options[i]), &sid);
 660                 if (rc) {
 661                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 662                                "(%s) failed for (dev %s, type "SB_TYPE_FMT") errno=%d\n",
 663                                mount_options[i], sb->s_id, SB_TYPE_ARGS(sb), rc);
 664                         goto out;
 665                 }
 666                 switch (flags[i]) {
 667                 case FSCONTEXT_MNT:
 668                         fscontext_sid = sid;
 669
 670                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 671                                         fscontext_sid))
 672                                 goto out_double_mount;
 673
 674                         sbsec->flags |= FSCONTEXT_MNT;
 675                         break;
 676                 case CONTEXT_MNT:
 677                         context_sid = sid;
 678
 679                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 680                                         context_sid))
 681                                 goto out_double_mount;
 682
 683                         sbsec->flags |= CONTEXT_MNT;
 684                         break;
 685                 case ROOTCONTEXT_MNT:
 686                         rootcontext_sid = sid;
 687
 688                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 689                                         rootcontext_sid))
 690                                 goto out_double_mount;
 691
 692                         sbsec->flags |= ROOTCONTEXT_MNT;
 693
 694                         break;
 695                 case DEFCONTEXT_MNT:
 696                         defcontext_sid = sid;
 697
 698                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 699                                         defcontext_sid))
 700                                 goto out_double_mount;
 701
 702                         sbsec->flags |= DEFCONTEXT_MNT;
 703
 704                         break;
 705                 default:
 706                         rc = -EINVAL;
 707                         goto out;
 708                 }
 709         }
 710
 711         if (sbsec->flags & SE_SBINITIALIZED) {
 712                 /* previously mounted with options, but not on this attempt? */
 713                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 714                         goto out_double_mount;
 715                 rc = 0;
 716                 goto out;
 717         }
 718
 719         if (strcmp(sb->s_type->name, "proc") == 0)
 720                 sbsec->flags |= SE_SBPROC;
 721
 722         if (!sbsec->behavior) {
 723                 /*
 724                  * Determine the labeling behavior to use for this
 725                  * filesystem type.
 726                  */
 727                 rc = security_fs_use(sb);
 728                 if (rc) {
 729                         printk(KERN_WARNING
 730                                 "%s: security_fs_use(%s) returned %d\n",
 731                                         __func__, sb->s_type->name, rc);
 732                         goto out;
 733                 }
 734         }
 735         /* sets the context of the superblock for the fs being mounted. */
 736         if (fscontext_sid) {
 737                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 738                 if (rc)
 739                         goto out;
 740
 741                 sbsec->sid = fscontext_sid;
 742         }
 743
 744         /*
 745          * Switch to using mount point labeling behavior.
 746          * sets the label used on all file below the mountpoint, and will set
 747          * the superblock context if not already set.
 748          */
 749         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 750                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 751                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 752         }
 753
 754         if (context_sid) {
 755                 if (!fscontext_sid) {
 756                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 757                                                           cred);
 758                         if (rc)
 759                                 goto out;
 760                         sbsec->sid = context_sid;
 761                 } else {
 762                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 763                                                              cred);
 764                         if (rc)
 765                                 goto out;
 766                 }
 767                 if (!rootcontext_sid)
 768                         rootcontext_sid = context_sid;
 769
 770                 sbsec->mntpoint_sid = context_sid;
 771                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 772         }
 773
 774         if (rootcontext_sid) {
 775                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 776                                                      cred);
 777                 if (rc)
 778                         goto out;
 779
 780                 root_isec->sid = rootcontext_sid;
 781                 root_isec->initialized = 1;
 782         }
 783
 784         if (defcontext_sid) {
 785                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 786                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 787                         rc = -EINVAL;
 788                         printk(KERN_WARNING "SELinux: defcontext option is "
 789                                "invalid for this filesystem type\n");
 790                         goto out;
 791                 }
 792
 793                 if (defcontext_sid != sbsec->def_sid) {
 794                         rc = may_context_mount_inode_relabel(defcontext_sid,
 795                                                              sbsec, cred);
 796                         if (rc)
 797                                 goto out;
 798                 }
 799
 800                 sbsec->def_sid = defcontext_sid;
 801         }
 802
 803         rc = sb_finish_set_opts(sb);
 804 out:
 805         mutex_unlock(&sbsec->lock);
 806         return rc;
 807 out_double_mount:
 808         rc = -EINVAL;
 809         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 810                "security settings for (dev %s, type "SB_TYPE_FMT")\n", sb->s_id,
 811                SB_TYPE_ARGS(sb));
 812         goto out;
 813 }
 814
 815 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 816                                     const struct super_block *newsb)
 817 {
 818         struct superblock_security_struct *old = oldsb->s_security;
 819         struct superblock_security_struct *new = newsb->s_security;
 820         char oldflags = old->flags & SE_MNTMASK;
 821         char newflags = new->flags & SE_MNTMASK;
 822
 823         if (oldflags != newflags)
 824                 goto mismatch;
 825         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 826                 goto mismatch;
 827         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 828                 goto mismatch;
 829         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 830                 goto mismatch;
 831         if (oldflags & ROOTCONTEXT_MNT) {
 832                 struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
 833                 struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
 834                 if (oldroot->sid != newroot->sid)
 835                         goto mismatch;
 836         }
 837         return 0;
 838 mismatch:
 839         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
 840                             "different security settings for (dev %s, "
 841                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 842         return -EBUSY;
 843 }
 844
 845 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 846                                         struct super_block *newsb)
 847 {
 848         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 849         struct superblock_security_struct *newsbsec = newsb->s_security;
 850
 851         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 852         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 853         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 854
 855         /*
 856          * if the parent was able to be mounted it clearly had no special lsm
 857          * mount options.  thus we can safely deal with this superblock later
 858          */
 859         if (!ss_initialized)
 860                 return 0;
 861
 862         /* how can we clone if the old one wasn't set up?? */
 863         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 864
 865         /* if fs is reusing a sb, make sure that the contexts match */
 866         if (newsbsec->flags & SE_SBINITIALIZED)
 867                 return selinux_cmp_sb_context(oldsb, newsb);
 868
 869         mutex_lock(&newsbsec->lock);
 870
 871         newsbsec->flags = oldsbsec->flags;
 872
 873         newsbsec->sid = oldsbsec->sid;
 874         newsbsec->def_sid = oldsbsec->def_sid;
 875         newsbsec->behavior = oldsbsec->behavior;
 876
 877         if (set_context) {
 878                 u32 sid = oldsbsec->mntpoint_sid;
 879
 880                 if (!set_fscontext)
 881                         newsbsec->sid = sid;
 882                 if (!set_rootcontext) {
 883                         struct inode *newinode = newsb->s_root->d_inode;
 884                         struct inode_security_struct *newisec = newinode->i_security;
 885                         newisec->sid = sid;
 886                 }
 887                 newsbsec->mntpoint_sid = sid;
 888         }
 889         if (set_rootcontext) {
 890                 const struct inode *oldinode = oldsb->s_root->d_inode;
 891                 const struct inode_security_struct *oldisec = oldinode->i_security;
 892                 struct inode *newinode = newsb->s_root->d_inode;
 893                 struct inode_security_struct *newisec = newinode->i_security;
 894
 895                 newisec->sid = oldisec->sid;
 896         }
 897
 898         sb_finish_set_opts(newsb);
 899         mutex_unlock(&newsbsec->lock);
 900         return 0;
 901 }
 902
 903 static int selinux_parse_opts_str(char *options,
 904                                   struct security_mnt_opts *opts)
 905 {
 906         char *p;
 907         char *context = NULL, *defcontext = NULL;
 908         char *fscontext = NULL, *rootcontext = NULL;
 909         int rc, num_mnt_opts = 0;
 910
 911         opts->num_mnt_opts = 0;
 912
 913         /* Standard string-based options. */
 914         while ((p = strsep(&options, "|")) != NULL) {
 915                 int token;
 916                 substring_t args[MAX_OPT_ARGS];
 917
 918                 if (!*p)
 919                         continue;
 920
 921                 token = match_token(p, tokens, args);
 922
 923                 switch (token) {
 924                 case Opt_context:
 925                         if (context || defcontext) {
 926                                 rc = -EINVAL;
 927                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 928                                 goto out_err;
 929                         }
 930                         context = match_strdup(&args[0]);
 931                         if (!context) {
 932                                 rc = -ENOMEM;
 933                                 goto out_err;
 934                         }
 935                         break;
 936
 937                 case Opt_fscontext:
 938                         if (fscontext) {
 939                                 rc = -EINVAL;
 940                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 941                                 goto out_err;
 942                         }
 943                         fscontext = match_strdup(&args[0]);
 944                         if (!fscontext) {
 945                                 rc = -ENOMEM;
 946                                 goto out_err;
 947                         }
 948                         break;
 949
 950                 case Opt_rootcontext:
 951                         if (rootcontext) {
 952                                 rc = -EINVAL;
 953                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 954                                 goto out_err;
 955                         }
 956                         rootcontext = match_strdup(&args[0]);
 957                         if (!rootcontext) {
 958                                 rc = -ENOMEM;
 959                                 goto out_err;
 960                         }
 961                         break;
 962
 963                 case Opt_defcontext:
 964                         if (context || defcontext) {
 965                                 rc = -EINVAL;
 966                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 967                                 goto out_err;
 968                         }
 969                         defcontext = match_strdup(&args[0]);
 970                         if (!defcontext) {
 971                                 rc = -ENOMEM;
 972                                 goto out_err;
 973                         }
 974                         break;
 975                 case Opt_labelsupport:
 976                         break;
 977                 default:
 978                         rc = -EINVAL;
 979                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 980                         goto out_err;
 981
 982                 }
 983         }
 984
 985         rc = -ENOMEM;
 986         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 987         if (!opts->mnt_opts)
 988                 goto out_err;
 989
 990         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 991         if (!opts->mnt_opts_flags) {
 992                 kfree(opts->mnt_opts);
 993                 goto out_err;
 994         }
 995
 996         if (fscontext) {
 997                 opts->mnt_opts[num_mnt_opts] = fscontext;
 998                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 999         }
1000         if (context) {
1001                 opts->mnt_opts[num_mnt_opts] = context;
1002                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1003         }
1004         if (rootcontext) {
1005                 opts->mnt_opts[num_mnt_opts] = rootcontext;
1006                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1007         }
1008         if (defcontext) {
1009                 opts->mnt_opts[num_mnt_opts] = defcontext;
1010                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1011         }
1012
1013         opts->num_mnt_opts = num_mnt_opts;
1014         return 0;
1015
1016 out_err:
1017         kfree(context);
1018         kfree(defcontext);
1019         kfree(fscontext);
1020         kfree(rootcontext);
1021         return rc;
1022 }
1023 /*
1024  * string mount options parsing and call set the sbsec
1025  */
1026 static int superblock_doinit(struct super_block *sb, void *data)
1027 {
1028         int rc = 0;
1029         char *options = data;
1030         struct security_mnt_opts opts;
1031
1032         security_init_mnt_opts(&opts);
1033
1034         if (!data)
1035                 goto out;
1036
1037         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1038
1039         rc = selinux_parse_opts_str(options, &opts);
1040         if (rc)
1041                 goto out_err;
1042
1043 out:
1044         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1045
1046 out_err:
1047         security_free_mnt_opts(&opts);
1048         return rc;
1049 }
1050
1051 static void selinux_write_opts(struct seq_file *m,
1052                                struct security_mnt_opts *opts)
1053 {
1054         int i;
1055         char *prefix;
1056
1057         for (i = 0; i < opts->num_mnt_opts; i++) {
1058                 char *has_comma;
1059
1060                 if (opts->mnt_opts[i])
1061                         has_comma = strchr(opts->mnt_opts[i], ',');
1062                 else
1063                         has_comma = NULL;
1064
1065                 switch (opts->mnt_opts_flags[i]) {
1066                 case CONTEXT_MNT:
1067                         prefix = CONTEXT_STR;
1068                         break;
1069                 case FSCONTEXT_MNT:
1070                         prefix = FSCONTEXT_STR;
1071                         break;
1072                 case ROOTCONTEXT_MNT:
1073                         prefix = ROOTCONTEXT_STR;
1074                         break;
1075                 case DEFCONTEXT_MNT:
1076                         prefix = DEFCONTEXT_STR;
1077                         break;
1078                 case SBLABEL_MNT:
1079                         seq_putc(m, ',');
1080                         seq_puts(m, LABELSUPP_STR);
1081                         continue;
1082                 default:
1083                         BUG();
1084                         return;
1085                 };
1086                 /* we need a comma before each option */
1087                 seq_putc(m, ',');
1088                 seq_puts(m, prefix);
1089                 if (has_comma)
1090                         seq_putc(m, '\"');
1091                 seq_puts(m, opts->mnt_opts[i]);
1092                 if (has_comma)
1093                         seq_putc(m, '\"');
1094         }
1095 }
1096
1097 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1098 {
1099         struct security_mnt_opts opts;
1100         int rc;
1101
1102         rc = selinux_get_mnt_opts(sb, &opts);
1103         if (rc) {
1104                 /* before policy load we may get EINVAL, don't show anything */
1105                 if (rc == -EINVAL)
1106                         rc = 0;
1107                 return rc;
1108         }
1109
1110         selinux_write_opts(m, &opts);
1111
1112         security_free_mnt_opts(&opts);
1113
1114         return rc;
1115 }
1116
1117 static inline u16 inode_mode_to_security_class(umode_t mode)
1118 {
1119         switch (mode & S_IFMT) {
1120         case S_IFSOCK:
1121                 return SECCLASS_SOCK_FILE;
1122         case S_IFLNK:
1123                 return SECCLASS_LNK_FILE;
1124         case S_IFREG:
1125                 return SECCLASS_FILE;
1126         case S_IFBLK:
1127                 return SECCLASS_BLK_FILE;
1128         case S_IFDIR:
1129                 return SECCLASS_DIR;
1130         case S_IFCHR:
1131                 return SECCLASS_CHR_FILE;
1132         case S_IFIFO:
1133                 return SECCLASS_FIFO_FILE;
1134
1135         }
1136
1137         return SECCLASS_FILE;
1138 }
1139
1140 static inline int default_protocol_stream(int protocol)
1141 {
1142         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1143 }
1144
1145 static inline int default_protocol_dgram(int protocol)
1146 {
1147         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1148 }
1149
1150 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1151 {
1152         switch (family) {
1153         case PF_UNIX:
1154                 switch (type) {
1155                 case SOCK_STREAM:
1156                 case SOCK_SEQPACKET:
1157                         return SECCLASS_UNIX_STREAM_SOCKET;
1158                 case SOCK_DGRAM:
1159                         return SECCLASS_UNIX_DGRAM_SOCKET;
1160                 }
1161                 break;
1162         case PF_INET:
1163         case PF_INET6:
1164                 switch (type) {
1165                 case SOCK_STREAM:
1166                         if (default_protocol_stream(protocol))
1167                                 return SECCLASS_TCP_SOCKET;
1168                         else
1169                                 return SECCLASS_RAWIP_SOCKET;
1170                 case SOCK_DGRAM:
1171                         if (default_protocol_dgram(protocol))
1172                                 return SECCLASS_UDP_SOCKET;
1173                         else
1174                                 return SECCLASS_RAWIP_SOCKET;
1175                 case SOCK_DCCP:
1176                         return SECCLASS_DCCP_SOCKET;
1177                 default:
1178                         return SECCLASS_RAWIP_SOCKET;
1179                 }
1180                 break;
1181         case PF_NETLINK:
1182                 switch (protocol) {
1183                 case NETLINK_ROUTE:
1184                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1185                 case NETLINK_FIREWALL:
1186                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1187                 case NETLINK_SOCK_DIAG:
1188                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1189                 case NETLINK_NFLOG:
1190                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1191                 case NETLINK_XFRM:
1192                         return SECCLASS_NETLINK_XFRM_SOCKET;
1193                 case NETLINK_SELINUX:
1194                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1195                 case NETLINK_AUDIT:
1196                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1197                 case NETLINK_IP6_FW:
1198                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1199                 case NETLINK_DNRTMSG:
1200                         return SECCLASS_NETLINK_DNRT_SOCKET;
1201                 case NETLINK_KOBJECT_UEVENT:
1202                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1203                 default:
1204                         return SECCLASS_NETLINK_SOCKET;
1205                 }
1206         case PF_PACKET:
1207                 return SECCLASS_PACKET_SOCKET;
1208         case PF_KEY:
1209                 return SECCLASS_KEY_SOCKET;
1210         case PF_APPLETALK:
1211                 return SECCLASS_APPLETALK_SOCKET;
1212         }
1213
1214         return SECCLASS_SOCKET;
1215 }
1216
1217 #ifdef CONFIG_PROC_FS
1218 static int selinux_proc_get_sid(struct dentry *dentry,
1219                                 u16 tclass,
1220                                 u32 *sid)
1221 {
1222         int rc;
1223         char *buffer, *path;
1224
1225         buffer = (char *)__get_free_page(GFP_KERNEL);
1226         if (!buffer)
1227                 return -ENOMEM;
1228
1229         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1230         if (IS_ERR(path))
1231                 rc = PTR_ERR(path);
1232         else {
1233                 /* each process gets a /proc/PID/ entry. Strip off the
1234                  * PID part to get a valid selinux labeling.
1235                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1236                 while (path[1] >= '0' && path[1] <= '9') {
1237                         path[1] = '/';
1238                         path++;
1239                 }
1240                 rc = security_genfs_sid("proc", path, tclass, sid);
1241         }
1242         free_page((unsigned long)buffer);
1243         return rc;
1244 }
1245 #else
1246 static int selinux_proc_get_sid(struct dentry *dentry,
1247                                 u16 tclass,
1248                                 u32 *sid)
1249 {
1250         return -EINVAL;
1251 }
1252 #endif
1253
1254 /* The inode's security attributes must be initialized before first use. */
1255 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1256 {
1257         struct superblock_security_struct *sbsec = NULL;
1258         struct inode_security_struct *isec = inode->i_security;
1259         u32 sid;
1260         struct dentry *dentry;
1261 #define INITCONTEXTLEN 255
1262         char *context = NULL;
1263         unsigned len = 0;
1264         int rc = 0;
1265
1266         if (isec->initialized)
1267                 goto out;
1268
1269         mutex_lock(&isec->lock);
1270         if (isec->initialized)
1271                 goto out_unlock;
1272
1273         sbsec = inode->i_sb->s_security;
1274         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1275                 /* Defer initialization until selinux_complete_init,
1276                    after the initial policy is loaded and the security
1277                    server is ready to handle calls. */
1278                 spin_lock(&sbsec->isec_lock);
1279                 if (list_empty(&isec->list))
1280                         list_add(&isec->list, &sbsec->isec_head);
1281                 spin_unlock(&sbsec->isec_lock);
1282                 goto out_unlock;
1283         }
1284
1285         switch (sbsec->behavior) {
1286         case SECURITY_FS_USE_NATIVE:
1287                 break;
1288         case SECURITY_FS_USE_XATTR:
1289                 if (!inode->i_op->getxattr) {
1290                         isec->sid = sbsec->def_sid;
1291                         break;
1292                 }
1293
1294                 /* Need a dentry, since the xattr API requires one.
1295                    Life would be simpler if we could just pass the inode. */
1296                 if (opt_dentry) {
1297                         /* Called from d_instantiate or d_splice_alias. */
1298                         dentry = dget(opt_dentry);
1299                 } else {
1300                         /* Called from selinux_complete_init, try to find a dentry. */
1301                         dentry = d_find_alias(inode);
1302                 }
1303                 if (!dentry) {
1304                         /*
1305                          * this is can be hit on boot when a file is accessed
1306                          * before the policy is loaded.  When we load policy we
1307                          * may find inodes that have no dentry on the
1308                          * sbsec->isec_head list.  No reason to complain as these
1309                          * will get fixed up the next time we go through
1310                          * inode_doinit with a dentry, before these inodes could
1311                          * be used again by userspace.
1312                          */
1313                         goto out_unlock;
1314                 }
1315
1316                 len = INITCONTEXTLEN;
1317                 context = kmalloc(len+1, GFP_NOFS);
1318                 if (!context) {
1319                         rc = -ENOMEM;
1320                         dput(dentry);
1321                         goto out_unlock;
1322                 }
1323                 context[len] = '\0';
1324                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1325                                            context, len);
1326                 if (rc == -ERANGE) {
1327                         kfree(context);
1328
1329                         /* Need a larger buffer.  Query for the right size. */
1330                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1331                                                    NULL, 0);
1332                         if (rc < 0) {
1333                                 dput(dentry);
1334                                 goto out_unlock;
1335                         }
1336                         len = rc;
1337                         context = kmalloc(len+1, GFP_NOFS);
1338                         if (!context) {
1339                                 rc = -ENOMEM;
1340                                 dput(dentry);
1341                                 goto out_unlock;
1342                         }
1343                         context[len] = '\0';
1344                         rc = inode->i_op->getxattr(dentry,
1345                                                    XATTR_NAME_SELINUX,
1346                                                    context, len);
1347                 }
1348                 dput(dentry);
1349                 if (rc < 0) {
1350                         if (rc != -ENODATA) {
1351                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1352                                        "%d for dev=%s ino=%ld\n", __func__,
1353                                        -rc, inode->i_sb->s_id, inode->i_ino);
1354                                 kfree(context);
1355                                 goto out_unlock;
1356                         }
1357                         /* Map ENODATA to the default file SID */
1358                         sid = sbsec->def_sid;
1359                         rc = 0;
1360                 } else {
1361                         rc = security_context_to_sid_default(context, rc, &sid,
1362                                                              sbsec->def_sid,
1363                                                              GFP_NOFS);
1364                         if (rc) {
1365                                 char *dev = inode->i_sb->s_id;
1366                                 unsigned long ino = inode->i_ino;
1367
1368                                 if (rc == -EINVAL) {
1369                                         if (printk_ratelimit())
1370                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1371                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1372                                                         "filesystem in question.\n", ino, dev, context);
1373                                 } else {
1374                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1375                                                "returned %d for dev=%s ino=%ld\n",
1376                                                __func__, context, -rc, dev, ino);
1377                                 }
1378                                 kfree(context);
1379                                 /* Leave with the unlabeled SID */
1380                                 rc = 0;
1381                                 break;
1382                         }
1383                 }
1384                 kfree(context);
1385                 isec->sid = sid;
1386                 break;
1387         case SECURITY_FS_USE_TASK:
1388                 isec->sid = isec->task_sid;
1389                 break;
1390         case SECURITY_FS_USE_TRANS:
1391                 /* Default to the fs SID. */
1392                 isec->sid = sbsec->sid;
1393
1394                 /* Try to obtain a transition SID. */
1395                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1396                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1397                                              isec->sclass, NULL, &sid);
1398                 if (rc)
1399                         goto out_unlock;
1400                 isec->sid = sid;
1401                 break;
1402         case SECURITY_FS_USE_MNTPOINT:
1403                 isec->sid = sbsec->mntpoint_sid;
1404                 break;
1405         default:
1406                 /* Default to the fs superblock SID. */
1407                 isec->sid = sbsec->sid;
1408
1409                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1410                         if (opt_dentry) {
1411                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1412                                 rc = selinux_proc_get_sid(opt_dentry,
1413                                                           isec->sclass,
1414                                                           &sid);
1415                                 if (rc)
1416                                         goto out_unlock;
1417                                 isec->sid = sid;
1418                         }
1419                 }
1420                 break;
1421         }
1422
1423         isec->initialized = 1;
1424
1425 out_unlock:
1426         mutex_unlock(&isec->lock);
1427 out:
1428         if (isec->sclass == SECCLASS_FILE)
1429                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1430         return rc;
1431 }
1432
1433 /* Convert a Linux signal to an access vector. */
1434 static inline u32 signal_to_av(int sig)
1435 {
1436         u32 perm = 0;
1437
1438         switch (sig) {
1439         case SIGCHLD:
1440                 /* Commonly granted from child to parent. */
1441                 perm = PROCESS__SIGCHLD;
1442                 break;
1443         case SIGKILL:
1444                 /* Cannot be caught or ignored */
1445                 perm = PROCESS__SIGKILL;
1446                 break;
1447         case SIGSTOP:
1448                 /* Cannot be caught or ignored */
1449                 perm = PROCESS__SIGSTOP;
1450                 break;
1451         default:
1452                 /* All other signals. */
1453                 perm = PROCESS__SIGNAL;
1454                 break;
1455         }
1456
1457         return perm;
1458 }
1459
1460 /*
1461  * Check permission between a pair of credentials
1462  * fork check, ptrace check, etc.
1463  */
1464 static int cred_has_perm(const struct cred *actor,
1465                          const struct cred *target,
1466                          u32 perms)
1467 {
1468         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1469
1470         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1471 }
1472
1473 /*
1474  * Check permission between a pair of tasks, e.g. signal checks,
1475  * fork check, ptrace check, etc.
1476  * tsk1 is the actor and tsk2 is the target
1477  * - this uses the default subjective creds of tsk1
1478  */
1479 static int task_has_perm(const struct task_struct *tsk1,
1480                          const struct task_struct *tsk2,
1481                          u32 perms)
1482 {
1483         const struct task_security_struct *__tsec1, *__tsec2;
1484         u32 sid1, sid2;
1485
1486         rcu_read_lock();
1487         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1488         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1489         rcu_read_unlock();
1490         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1491 }
1492
1493 /*
1494  * Check permission between current and another task, e.g. signal checks,
1495  * fork check, ptrace check, etc.
1496  * current is the actor and tsk2 is the target
1497  * - this uses current's subjective creds
1498  */
1499 static int current_has_perm(const struct task_struct *tsk,
1500                             u32 perms)
1501 {
1502         u32 sid, tsid;
1503
1504         sid = current_sid();
1505         tsid = task_sid(tsk);
1506         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1507 }
1508
1509 #if CAP_LAST_CAP > 63
1510 #error Fix SELinux to handle capabilities > 63.
1511 #endif
1512
1513 /* Check whether a task is allowed to use a capability. */
1514 static int cred_has_capability(const struct cred *cred,
1515                                int cap, int audit)
1516 {
1517         struct common_audit_data ad;
1518         struct av_decision avd;
1519         u16 sclass;
1520         u32 sid = cred_sid(cred);
1521         u32 av = CAP_TO_MASK(cap);
1522         int rc;
1523
1524         ad.type = LSM_AUDIT_DATA_CAP;
1525         ad.u.cap = cap;
1526
1527         switch (CAP_TO_INDEX(cap)) {
1528         case 0:
1529                 sclass = SECCLASS_CAPABILITY;
1530                 break;
1531         case 1:
1532                 sclass = SECCLASS_CAPABILITY2;
1533                 break;
1534         default:
1535                 printk(KERN_ERR
1536                        "SELinux:  out of range capability %d\n", cap);
1537                 BUG();
1538                 return -EINVAL;
1539         }
1540
1541         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1542         if (audit == SECURITY_CAP_AUDIT) {
1543                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1544                 if (rc2)
1545                         return rc2;
1546         }
1547         return rc;
1548 }
1549
1550 /* Check whether a task is allowed to use a system operation. */
1551 static int task_has_system(struct task_struct *tsk,
1552                            u32 perms)
1553 {
1554         u32 sid = task_sid(tsk);
1555
1556         return avc_has_perm(sid, SECINITSID_KERNEL,
1557                             SECCLASS_SYSTEM, perms, NULL);
1558 }
1559
1560 /* Check whether a task has a particular permission to an inode.
1561    The 'adp' parameter is optional and allows other audit
1562    data to be passed (e.g. the dentry). */
1563 static int inode_has_perm(const struct cred *cred,
1564                           struct inode *inode,
1565                           u32 perms,
1566                           struct common_audit_data *adp)
1567 {
1568         struct inode_security_struct *isec;
1569         u32 sid;
1570
1571         validate_creds(cred);
1572
1573         if (unlikely(IS_PRIVATE(inode)))
1574                 return 0;
1575
1576         sid = cred_sid(cred);
1577         isec = inode->i_security;
1578
1579         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1580 }
1581
1582 /* Same as inode_has_perm, but pass explicit audit data containing
1583    the dentry to help the auditing code to more easily generate the
1584    pathname if needed. */
1585 static inline int dentry_has_perm(const struct cred *cred,
1586                                   struct dentry *dentry,
1587                                   u32 av)
1588 {
1589         struct inode *inode = dentry->d_inode;
1590         struct common_audit_data ad;
1591
1592         ad.type = LSM_AUDIT_DATA_DENTRY;
1593         ad.u.dentry = dentry;
1594         return inode_has_perm(cred, inode, av, &ad);
1595 }
1596
1597 /* Same as inode_has_perm, but pass explicit audit data containing
1598    the path to help the auditing code to more easily generate the
1599    pathname if needed. */
1600 static inline int path_has_perm(const struct cred *cred,
1601                                 struct path *path,
1602                                 u32 av)
1603 {
1604         struct inode *inode = path->dentry->d_inode;
1605         struct common_audit_data ad;
1606
1607         ad.type = LSM_AUDIT_DATA_PATH;
1608         ad.u.path = *path;
1609         return inode_has_perm(cred, inode, av, &ad);
1610 }
1611
1612 /* Same as path_has_perm, but uses the inode from the file struct. */
1613 static inline int file_path_has_perm(const struct cred *cred,
1614                                      struct file *file,
1615                                      u32 av)
1616 {
1617         struct common_audit_data ad;
1618
1619         ad.type = LSM_AUDIT_DATA_PATH;
1620         ad.u.path = file->f_path;
1621         return inode_has_perm(cred, file_inode(file), av, &ad);
1622 }
1623
1624 /* Check whether a task can use an open file descriptor to
1625    access an inode in a given way.  Check access to the
1626    descriptor itself, and then use dentry_has_perm to
1627    check a particular permission to the file.
1628    Access to the descriptor is implicitly granted if it
1629    has the same SID as the process.  If av is zero, then
1630    access to the file is not checked, e.g. for cases
1631    where only the descriptor is affected like seek. */
1632 static int file_has_perm(const struct cred *cred,
1633                          struct file *file,
1634                          u32 av)
1635 {
1636         struct file_security_struct *fsec = file->f_security;
1637         struct inode *inode = file_inode(file);
1638         struct common_audit_data ad;
1639         u32 sid = cred_sid(cred);
1640         int rc;
1641
1642         ad.type = LSM_AUDIT_DATA_PATH;
1643         ad.u.path = file->f_path;
1644
1645         if (sid != fsec->sid) {
1646                 rc = avc_has_perm(sid, fsec->sid,
1647                                   SECCLASS_FD,
1648                                   FD__USE,
1649                                   &ad);
1650                 if (rc)
1651                         goto out;
1652         }
1653
1654         /* av is zero if only checking access to the descriptor. */
1655         rc = 0;
1656         if (av)
1657                 rc = inode_has_perm(cred, inode, av, &ad);
1658
1659 out:
1660         return rc;
1661 }
1662
1663 /* Check whether a task can create a file. */
1664 static int may_create(struct inode *dir,
1665                       struct dentry *dentry,
1666                       u16 tclass)
1667 {
1668         const struct task_security_struct *tsec = current_security();
1669         struct inode_security_struct *dsec;
1670         struct superblock_security_struct *sbsec;
1671         u32 sid, newsid;
1672         struct common_audit_data ad;
1673         int rc;
1674
1675         dsec = dir->i_security;
1676         sbsec = dir->i_sb->s_security;
1677
1678         sid = tsec->sid;
1679         newsid = tsec->create_sid;
1680
1681         ad.type = LSM_AUDIT_DATA_DENTRY;
1682         ad.u.dentry = dentry;
1683
1684         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1685                           DIR__ADD_NAME | DIR__SEARCH,
1686                           &ad);
1687         if (rc)
1688                 return rc;
1689
1690         if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1691                 rc = security_transition_sid(sid, dsec->sid, tclass,
1692                                              &dentry->d_name, &newsid);
1693                 if (rc)
1694                         return rc;
1695         }
1696
1697         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1698         if (rc)
1699                 return rc;
1700
1701         return avc_has_perm(newsid, sbsec->sid,
1702                             SECCLASS_FILESYSTEM,
1703                             FILESYSTEM__ASSOCIATE, &ad);
1704 }
1705
1706 /* Check whether a task can create a key. */
1707 static int may_create_key(u32 ksid,
1708                           struct task_struct *ctx)
1709 {
1710         u32 sid = task_sid(ctx);
1711
1712         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1713 }
1714
1715 #define MAY_LINK        0
1716 #define MAY_UNLINK      1
1717 #define MAY_RMDIR       2
1718
1719 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1720 static int may_link(struct inode *dir,
1721                     struct dentry *dentry,
1722                     int kind)
1723
1724 {
1725         struct inode_security_struct *dsec, *isec;
1726         struct common_audit_data ad;
1727         u32 sid = current_sid();
1728         u32 av;
1729         int rc;
1730
1731         dsec = dir->i_security;
1732         isec = dentry->d_inode->i_security;
1733
1734         ad.type = LSM_AUDIT_DATA_DENTRY;
1735         ad.u.dentry = dentry;
1736
1737         av = DIR__SEARCH;
1738         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1739         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1740         if (rc)
1741                 return rc;
1742
1743         switch (kind) {
1744         case MAY_LINK:
1745                 av = FILE__LINK;
1746                 break;
1747         case MAY_UNLINK:
1748                 av = FILE__UNLINK;
1749                 break;
1750         case MAY_RMDIR:
1751                 av = DIR__RMDIR;
1752                 break;
1753         default:
1754                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1755                         __func__, kind);
1756                 return 0;
1757         }
1758
1759         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1760         return rc;
1761 }
1762
1763 static inline int may_rename(struct inode *old_dir,
1764                              struct dentry *old_dentry,
1765                              struct inode *new_dir,
1766                              struct dentry *new_dentry)
1767 {
1768         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1769         struct common_audit_data ad;
1770         u32 sid = current_sid();
1771         u32 av;
1772         int old_is_dir, new_is_dir;
1773         int rc;
1774
1775         old_dsec = old_dir->i_security;
1776         old_isec = old_dentry->d_inode->i_security;
1777         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1778         new_dsec = new_dir->i_security;
1779
1780         ad.type = LSM_AUDIT_DATA_DENTRY;
1781
1782         ad.u.dentry = old_dentry;
1783         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1784                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1785         if (rc)
1786                 return rc;
1787         rc = avc_has_perm(sid, old_isec->sid,
1788                           old_isec->sclass, FILE__RENAME, &ad);
1789         if (rc)
1790                 return rc;
1791         if (old_is_dir && new_dir != old_dir) {
1792                 rc = avc_has_perm(sid, old_isec->sid,
1793                                   old_isec->sclass, DIR__REPARENT, &ad);
1794                 if (rc)
1795                         return rc;
1796         }
1797
1798         ad.u.dentry = new_dentry;
1799         av = DIR__ADD_NAME | DIR__SEARCH;
1800         if (new_dentry->d_inode)
1801                 av |= DIR__REMOVE_NAME;
1802         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1803         if (rc)
1804                 return rc;
1805         if (new_dentry->d_inode) {
1806                 new_isec = new_dentry->d_inode->i_security;
1807                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1808                 rc = avc_has_perm(sid, new_isec->sid,
1809                                   new_isec->sclass,
1810                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1811                 if (rc)
1812                         return rc;
1813         }
1814
1815         return 0;
1816 }
1817
1818 /* Check whether a task can perform a filesystem operation. */
1819 static int superblock_has_perm(const struct cred *cred,
1820                                struct super_block *sb,
1821                                u32 perms,
1822                                struct common_audit_data *ad)
1823 {
1824         struct superblock_security_struct *sbsec;
1825         u32 sid = cred_sid(cred);
1826
1827         sbsec = sb->s_security;
1828         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1829 }
1830
1831 /* Convert a Linux mode and permission mask to an access vector. */
1832 static inline u32 file_mask_to_av(int mode, int mask)
1833 {
1834         u32 av = 0;
1835
1836         if (!S_ISDIR(mode)) {
1837                 if (mask & MAY_EXEC)
1838                         av |= FILE__EXECUTE;
1839                 if (mask & MAY_READ)
1840                         av |= FILE__READ;
1841
1842                 if (mask & MAY_APPEND)
1843                         av |= FILE__APPEND;
1844                 else if (mask & MAY_WRITE)
1845                         av |= FILE__WRITE;
1846
1847         } else {
1848                 if (mask & MAY_EXEC)
1849                         av |= DIR__SEARCH;
1850                 if (mask & MAY_WRITE)
1851                         av |= DIR__WRITE;
1852                 if (mask & MAY_READ)
1853                         av |= DIR__READ;
1854         }
1855
1856         return av;
1857 }
1858
1859 /* Convert a Linux file to an access vector. */
1860 static inline u32 file_to_av(struct file *file)
1861 {
1862         u32 av = 0;
1863
1864         if (file->f_mode & FMODE_READ)
1865                 av |= FILE__READ;
1866         if (file->f_mode & FMODE_WRITE) {
1867                 if (file->f_flags & O_APPEND)
1868                         av |= FILE__APPEND;
1869                 else
1870                         av |= FILE__WRITE;
1871         }
1872         if (!av) {
1873                 /*
1874                  * Special file opened with flags 3 for ioctl-only use.
1875                  */
1876                 av = FILE__IOCTL;
1877         }
1878
1879         return av;
1880 }
1881
1882 /*
1883  * Convert a file to an access vector and include the correct open
1884  * open permission.
1885  */
1886 static inline u32 open_file_to_av(struct file *file)
1887 {
1888         u32 av = file_to_av(file);
1889
1890         if (selinux_policycap_openperm)
1891                 av |= FILE__OPEN;
1892
1893         return av;
1894 }
1895
1896 /* Hook functions begin here. */
1897
1898 static int selinux_ptrace_access_check(struct task_struct *child,
1899                                      unsigned int mode)
1900 {
1901         int rc;
1902
1903         rc = cap_ptrace_access_check(child, mode);
1904         if (rc)
1905                 return rc;
1906
1907         if (mode & PTRACE_MODE_READ) {
1908                 u32 sid = current_sid();
1909                 u32 csid = task_sid(child);
1910                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1911         }
1912
1913         return current_has_perm(child, PROCESS__PTRACE);
1914 }
1915
1916 static int selinux_ptrace_traceme(struct task_struct *parent)
1917 {
1918         int rc;
1919
1920         rc = cap_ptrace_traceme(parent);
1921         if (rc)
1922                 return rc;
1923
1924         return task_has_perm(parent, current, PROCESS__PTRACE);
1925 }
1926
1927 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1928                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1929 {
1930         int error;
1931
1932         error = current_has_perm(target, PROCESS__GETCAP);
1933         if (error)
1934                 return error;
1935
1936         return cap_capget(target, effective, inheritable, permitted);
1937 }
1938
1939 static int selinux_capset(struct cred *new, const struct cred *old,
1940                           const kernel_cap_t *effective,
1941                           const kernel_cap_t *inheritable,
1942                           const kernel_cap_t *permitted)
1943 {
1944         int error;
1945
1946         error = cap_capset(new, old,
1947                                       effective, inheritable, permitted);
1948         if (error)
1949                 return error;
1950
1951         return cred_has_perm(old, new, PROCESS__SETCAP);
1952 }
1953
1954 /*
1955  * (This comment used to live with the selinux_task_setuid hook,
1956  * which was removed).
1957  *
1958  * Since setuid only affects the current process, and since the SELinux
1959  * controls are not based on the Linux identity attributes, SELinux does not
1960  * need to control this operation.  However, SELinux does control the use of
1961  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1962  */
1963
1964 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1965                            int cap, int audit)
1966 {
1967         int rc;
1968
1969         rc = cap_capable(cred, ns, cap, audit);
1970         if (rc)
1971                 return rc;
1972
1973         return cred_has_capability(cred, cap, audit);
1974 }
1975
1976 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1977 {
1978         const struct cred *cred = current_cred();
1979         int rc = 0;
1980
1981         if (!sb)
1982                 return 0;
1983
1984         switch (cmds) {
1985         case Q_SYNC:
1986         case Q_QUOTAON:
1987         case Q_QUOTAOFF:
1988         case Q_SETINFO:
1989         case Q_SETQUOTA:
1990                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1991                 break;
1992         case Q_GETFMT:
1993         case Q_GETINFO:
1994         case Q_GETQUOTA:
1995                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1996                 break;
1997         default:
1998                 rc = 0;  /* let the kernel handle invalid cmds */
1999                 break;
2000         }
2001         return rc;
2002 }
2003
2004 static int selinux_quota_on(struct dentry *dentry)
2005 {
2006         const struct cred *cred = current_cred();
2007
2008         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2009 }
2010
2011 static int selinux_syslog(int type)
2012 {
2013         int rc;
2014
2015         switch (type) {
2016         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2017         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2018                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2019                 break;
2020         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2021         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2022         /* Set level of messages printed to console */
2023         case SYSLOG_ACTION_CONSOLE_LEVEL:
2024                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2025                 break;
2026         case SYSLOG_ACTION_CLOSE:       /* Close log */
2027         case SYSLOG_ACTION_OPEN:        /* Open log */
2028         case SYSLOG_ACTION_READ:        /* Read from log */
2029         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
2030         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2031         default:
2032                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2033                 break;
2034         }
2035         return rc;
2036 }
2037
2038 /*
2039  * Check that a process has enough memory to allocate a new virtual
2040  * mapping. 0 means there is enough memory for the allocation to
2041  * succeed and -ENOMEM implies there is not.
2042  *
2043  * Do not audit the selinux permission check, as this is applied to all
2044  * processes that allocate mappings.
2045  */
2046 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2047 {
2048         int rc, cap_sys_admin = 0;
2049
2050         rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2051                              SECURITY_CAP_NOAUDIT);
2052         if (rc == 0)
2053                 cap_sys_admin = 1;
2054
2055         return __vm_enough_memory(mm, pages, cap_sys_admin);
2056 }
2057
2058 /* binprm security operations */
2059
2060 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2061 {
2062         const struct task_security_struct *old_tsec;
2063         struct task_security_struct *new_tsec;
2064         struct inode_security_struct *isec;
2065         struct common_audit_data ad;
2066         struct inode *inode = file_inode(bprm->file);
2067         int rc;
2068
2069         rc = cap_bprm_set_creds(bprm);
2070         if (rc)
2071                 return rc;
2072
2073         /* SELinux context only depends on initial program or script and not
2074          * the script interpreter */
2075         if (bprm->cred_prepared)
2076                 return 0;
2077
2078         old_tsec = current_security();
2079         new_tsec = bprm->cred->security;
2080         isec = inode->i_security;
2081
2082         /* Default to the current task SID. */
2083         new_tsec->sid = old_tsec->sid;
2084         new_tsec->osid = old_tsec->sid;
2085
2086         /* Reset fs, key, and sock SIDs on execve. */
2087         new_tsec->create_sid = 0;
2088         new_tsec->keycreate_sid = 0;
2089         new_tsec->sockcreate_sid = 0;
2090
2091         if (old_tsec->exec_sid) {
2092                 new_tsec->sid = old_tsec->exec_sid;
2093                 /* Reset exec SID on execve. */
2094                 new_tsec->exec_sid = 0;
2095
2096                 /*
2097                  * Minimize confusion: if no_new_privs and a transition is
2098                  * explicitly requested, then fail the exec.
2099                  */
2100                 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2101                         return -EPERM;
2102         } else {
2103                 /* Check for a default transition on this program. */
2104                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2105                                              SECCLASS_PROCESS, NULL,
2106                                              &new_tsec->sid);
2107                 if (rc)
2108                         return rc;
2109         }
2110
2111         ad.type = LSM_AUDIT_DATA_PATH;
2112         ad.u.path = bprm->file->f_path;
2113
2114         if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2115             (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2116                 new_tsec->sid = old_tsec->sid;
2117
2118         if (new_tsec->sid == old_tsec->sid) {
2119                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2120                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2121                 if (rc)
2122                         return rc;
2123         } else {
2124                 /* Check permissions for the transition. */
2125                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2126                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2127                 if (rc)
2128                         return rc;
2129
2130                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2131                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2132                 if (rc)
2133                         return rc;
2134
2135                 /* Check for shared state */
2136                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2137                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2138                                           SECCLASS_PROCESS, PROCESS__SHARE,
2139                                           NULL);
2140                         if (rc)
2141                                 return -EPERM;
2142                 }
2143
2144                 /* Make sure that anyone attempting to ptrace over a task that
2145                  * changes its SID has the appropriate permit */
2146                 if (bprm->unsafe &
2147                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2148                         struct task_struct *tracer;
2149                         struct task_security_struct *sec;
2150                         u32 ptsid = 0;
2151
2152                         rcu_read_lock();
2153                         tracer = ptrace_parent(current);
2154                         if (likely(tracer != NULL)) {
2155                                 sec = __task_cred(tracer)->security;
2156                                 ptsid = sec->sid;
2157                         }
2158                         rcu_read_unlock();
2159
2160                         if (ptsid != 0) {
2161                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2162                                                   SECCLASS_PROCESS,
2163                                                   PROCESS__PTRACE, NULL);
2164                                 if (rc)
2165                                         return -EPERM;
2166                         }
2167                 }
2168
2169                 /* Clear any possibly unsafe personality bits on exec: */
2170                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2171         }
2172
2173         return 0;
2174 }
2175
2176 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2177 {
2178         const struct task_security_struct *tsec = current_security();
2179         u32 sid, osid;
2180         int atsecure = 0;
2181
2182         sid = tsec->sid;
2183         osid = tsec->osid;
2184
2185         if (osid != sid) {
2186                 /* Enable secure mode for SIDs transitions unless
2187                    the noatsecure permission is granted between
2188                    the two SIDs, i.e. ahp returns 0. */
2189                 atsecure = avc_has_perm(osid, sid,
2190                                         SECCLASS_PROCESS,
2191                                         PROCESS__NOATSECURE, NULL);
2192         }
2193
2194         return (atsecure || cap_bprm_secureexec(bprm));
2195 }
2196
2197 static int match_file(const void *p, struct file *file, unsigned fd)
2198 {
2199         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2200 }
2201
2202 /* Derived from fs/exec.c:flush_old_files. */
2203 static inline void flush_unauthorized_files(const struct cred *cred,
2204                                             struct files_struct *files)
2205 {
2206         struct file *file, *devnull = NULL;
2207         struct tty_struct *tty;
2208         int drop_tty = 0;
2209         unsigned n;
2210
2211         tty = get_current_tty();
2212         if (tty) {
2213                 spin_lock(&tty_files_lock);
2214                 if (!list_empty(&tty->tty_files)) {
2215                         struct tty_file_private *file_priv;
2216
2217                         /* Revalidate access to controlling tty.
2218                            Use file_path_has_perm on the tty path directly
2219                            rather than using file_has_perm, as this particular
2220                            open file may belong to another process and we are
2221                            only interested in the inode-based check here. */
2222                         file_priv = list_first_entry(&tty->tty_files,
2223                                                 struct tty_file_private, list);
2224                         file = file_priv->file;
2225                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2226                                 drop_tty = 1;
2227                 }
2228                 spin_unlock(&tty_files_lock);
2229                 tty_kref_put(tty);
2230         }
2231         /* Reset controlling tty. */
2232         if (drop_tty)
2233                 no_tty();
2234
2235         /* Revalidate access to inherited open files. */
2236         n = iterate_fd(files, 0, match_file, cred);
2237         if (!n) /* none found? */
2238                 return;
2239
2240         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2241         if (IS_ERR(devnull))
2242                 devnull = NULL;
2243         /* replace all the matching ones with this */
2244         do {
2245                 replace_fd(n - 1, devnull, 0);
2246         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2247         if (devnull)
2248                 fput(devnull);
2249 }
2250
2251 /*
2252  * Prepare a process for imminent new credential changes due to exec
2253  */
2254 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2255 {
2256         struct task_security_struct *new_tsec;
2257         struct rlimit *rlim, *initrlim;
2258         int rc, i;
2259
2260         new_tsec = bprm->cred->security;
2261         if (new_tsec->sid == new_tsec->osid)
2262                 return;
2263
2264         /* Close files for which the new task SID is not authorized. */
2265         flush_unauthorized_files(bprm->cred, current->files);
2266
2267         /* Always clear parent death signal on SID transitions. */
2268         current->pdeath_signal = 0;
2269
2270         /* Check whether the new SID can inherit resource limits from the old
2271          * SID.  If not, reset all soft limits to the lower of the current
2272          * task's hard limit and the init task's soft limit.
2273          *
2274          * Note that the setting of hard limits (even to lower them) can be
2275          * controlled by the setrlimit check.  The inclusion of the init task's
2276          * soft limit into the computation is to avoid resetting soft limits
2277          * higher than the default soft limit for cases where the default is
2278          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2279          */
2280         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2281                           PROCESS__RLIMITINH, NULL);
2282         if (rc) {
2283                 /* protect against do_prlimit() */
2284                 task_lock(current);
2285                 for (i = 0; i < RLIM_NLIMITS; i++) {
2286                         rlim = current->signal->rlim + i;
2287                         initrlim = init_task.signal->rlim + i;
2288                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2289                 }
2290                 task_unlock(current);
2291                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2292         }
2293 }
2294
2295 /*
2296  * Clean up the process immediately after the installation of new credentials
2297  * due to exec
2298  */
2299 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2300 {
2301         const struct task_security_struct *tsec = current_security();
2302         struct itimerval itimer;
2303         u32 osid, sid;
2304         int rc, i;
2305
2306         osid = tsec->osid;
2307         sid = tsec->sid;
2308
2309         if (sid == osid)
2310                 return;
2311
2312         /* Check whether the new SID can inherit signal state from the old SID.
2313          * If not, clear itimers to avoid subsequent signal generation and
2314          * flush and unblock signals.
2315          *
2316          * This must occur _after_ the task SID has been updated so that any
2317          * kill done after the flush will be checked against the new SID.
2318          */
2319         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2320         if (rc) {
2321                 memset(&itimer, 0, sizeof itimer);
2322                 for (i = 0; i < 3; i++)
2323                         do_setitimer(i, &itimer, NULL);
2324                 spin_lock_irq(&current->sighand->siglock);
2325                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2326                         __flush_signals(current);
2327                         flush_signal_handlers(current, 1);
2328                         sigemptyset(&current->blocked);
2329                 }
2330                 spin_unlock_irq(&current->sighand->siglock);
2331         }
2332
2333         /* Wake up the parent if it is waiting so that it can recheck
2334          * wait permission to the new task SID. */
2335         read_lock(&tasklist_lock);
2336         __wake_up_parent(current, current->real_parent);
2337         read_unlock(&tasklist_lock);
2338 }
2339
2340 /* superblock security operations */
2341
2342 static int selinux_sb_alloc_security(struct super_block *sb)
2343 {
2344         return superblock_alloc_security(sb);
2345 }
2346
2347 static void selinux_sb_free_security(struct super_block *sb)
2348 {
2349         superblock_free_security(sb);
2350 }
2351
2352 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2353 {
2354         if (plen > olen)
2355                 return 0;
2356
2357         return !memcmp(prefix, option, plen);
2358 }
2359
2360 static inline int selinux_option(char *option, int len)
2361 {
2362         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2363                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2364                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2365                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2366                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2367 }
2368
2369 static inline void take_option(char **to, char *from, int *first, int len)
2370 {
2371         if (!*first) {
2372                 **to = ',';
2373                 *to += 1;
2374         } else
2375                 *first = 0;
2376         memcpy(*to, from, len);
2377         *to += len;
2378 }
2379
2380 static inline void take_selinux_option(char **to, char *from, int *first,
2381                                        int len)
2382 {
2383         int current_size = 0;
2384
2385         if (!*first) {
2386                 **to = '|';
2387                 *to += 1;
2388         } else
2389                 *first = 0;
2390
2391         while (current_size < len) {
2392                 if (*from != '"') {
2393                         **to = *from;
2394                         *to += 1;
2395                 }
2396                 from += 1;
2397                 current_size += 1;
2398         }
2399 }
2400
2401 static int selinux_sb_copy_data(char *orig, char *copy)
2402 {
2403         int fnosec, fsec, rc = 0;
2404         char *in_save, *in_curr, *in_end;
2405         char *sec_curr, *nosec_save, *nosec;
2406         int open_quote = 0;
2407
2408         in_curr = orig;
2409         sec_curr = copy;
2410
2411         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2412         if (!nosec) {
2413                 rc = -ENOMEM;
2414                 goto out;
2415         }
2416
2417         nosec_save = nosec;
2418         fnosec = fsec = 1;
2419         in_save = in_end = orig;
2420
2421         do {
2422                 if (*in_end == '"')
2423                         open_quote = !open_quote;
2424                 if ((*in_end == ',' && open_quote == 0) ||
2425                                 *in_end == '\0') {
2426                         int len = in_end - in_curr;
2427
2428                         if (selinux_option(in_curr, len))
2429                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2430                         else
2431                                 take_option(&nosec, in_curr, &fnosec, len);
2432
2433                         in_curr = in_end + 1;
2434                 }
2435         } while (*in_end++);
2436
2437         strcpy(in_save, nosec_save);
2438         free_page((unsigned long)nosec_save);
2439 out:
2440         return rc;
2441 }
2442
2443 static int selinux_sb_remount(struct super_block *sb, void *data)
2444 {
2445         int rc, i, *flags;
2446         struct security_mnt_opts opts;
2447         char *secdata, **mount_options;
2448         struct superblock_security_struct *sbsec = sb->s_security;
2449
2450         if (!(sbsec->flags & SE_SBINITIALIZED))
2451                 return 0;
2452
2453         if (!data)
2454                 return 0;
2455
2456         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2457                 return 0;
2458
2459         security_init_mnt_opts(&opts);
2460         secdata = alloc_secdata();
2461         if (!secdata)
2462                 return -ENOMEM;
2463         rc = selinux_sb_copy_data(data, secdata);
2464         if (rc)
2465                 goto out_free_secdata;
2466
2467         rc = selinux_parse_opts_str(secdata, &opts);
2468         if (rc)
2469                 goto out_free_secdata;
2470
2471         mount_options = opts.mnt_opts;
2472         flags = opts.mnt_opts_flags;
2473
2474         for (i = 0; i < opts.num_mnt_opts; i++) {
2475                 u32 sid;
2476                 size_t len;
2477
2478                 if (flags[i] == SBLABEL_MNT)
2479                         continue;
2480                 len = strlen(mount_options[i]);
2481                 rc = security_context_to_sid(mount_options[i], len, &sid);
2482                 if (rc) {
2483                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2484                                "(%s) failed for (dev %s, type "SB_TYPE_FMT") errno=%d\n",
2485                                mount_options[i], sb->s_id, SB_TYPE_ARGS(sb), rc);
2486                         goto out_free_opts;
2487                 }
2488                 rc = -EINVAL;
2489                 switch (flags[i]) {
2490                 case FSCONTEXT_MNT:
2491                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2492                                 goto out_bad_option;
2493                         break;
2494                 case CONTEXT_MNT:
2495                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2496                                 goto out_bad_option;
2497                         break;
2498                 case ROOTCONTEXT_MNT: {
2499                         struct inode_security_struct *root_isec;
2500                         root_isec = sb->s_root->d_inode->i_security;
2501
2502                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2503                                 goto out_bad_option;
2504                         break;
2505                 }
2506                 case DEFCONTEXT_MNT:
2507                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2508                                 goto out_bad_option;
2509                         break;
2510                 default:
2511                         goto out_free_opts;
2512                 }
2513         }
2514
2515         rc = 0;
2516 out_free_opts:
2517         security_free_mnt_opts(&opts);
2518 out_free_secdata:
2519         free_secdata(secdata);
2520         return rc;
2521 out_bad_option:
2522         printk(KERN_WARNING "SELinux: unable to change security options "
2523                "during remount (dev %s, type "SB_TYPE_FMT")\n", sb->s_id,
2524                SB_TYPE_ARGS(sb));
2525         goto out_free_opts;
2526 }
2527
2528 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2529 {
2530         const struct cred *cred = current_cred();
2531         struct common_audit_data ad;
2532         int rc;
2533
2534         rc = superblock_doinit(sb, data);
2535         if (rc)
2536                 return rc;
2537
2538         /* Allow all mounts performed by the kernel */
2539         if (flags & MS_KERNMOUNT)
2540                 return 0;
2541
2542         ad.type = LSM_AUDIT_DATA_DENTRY;
2543         ad.u.dentry = sb->s_root;
2544         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2545 }
2546
2547 static int selinux_sb_statfs(struct dentry *dentry)
2548 {
2549         const struct cred *cred = current_cred();
2550         struct common_audit_data ad;
2551
2552         ad.type = LSM_AUDIT_DATA_DENTRY;
2553         ad.u.dentry = dentry->d_sb->s_root;
2554         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2555 }
2556
2557 static int selinux_mount(const char *dev_name,
2558                          struct path *path,
2559                          const char *type,
2560                          unsigned long flags,
2561                          void *data)
2562 {
2563         const struct cred *cred = current_cred();
2564
2565         if (flags & MS_REMOUNT)
2566                 return superblock_has_perm(cred, path->dentry->d_sb,
2567                                            FILESYSTEM__REMOUNT, NULL);
2568         else
2569                 return path_has_perm(cred, path, FILE__MOUNTON);
2570 }
2571
2572 static int selinux_umount(struct vfsmount *mnt, int flags)
2573 {
2574         const struct cred *cred = current_cred();
2575
2576         return superblock_has_perm(cred, mnt->mnt_sb,
2577                                    FILESYSTEM__UNMOUNT, NULL);
2578 }
2579
2580 /* inode security operations */
2581
2582 static int selinux_inode_alloc_security(struct inode *inode)
2583 {
2584         return inode_alloc_security(inode);
2585 }
2586
2587 static void selinux_inode_free_security(struct inode *inode)
2588 {
2589         inode_free_security(inode);
2590 }
2591
2592 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2593                                         struct qstr *name, void **ctx,
2594                                         u32 *ctxlen)
2595 {
2596         const struct cred *cred = current_cred();
2597         struct task_security_struct *tsec;
2598         struct inode_security_struct *dsec;
2599         struct superblock_security_struct *sbsec;
2600         struct inode *dir = dentry->d_parent->d_inode;
2601         u32 newsid;
2602         int rc;
2603
2604         tsec = cred->security;
2605         dsec = dir->i_security;
2606         sbsec = dir->i_sb->s_security;
2607
2608         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2609                 newsid = tsec->create_sid;
2610         } else {
2611                 rc = security_transition_sid(tsec->sid, dsec->sid,
2612                                              inode_mode_to_security_class(mode),
2613                                              name,
2614                                              &newsid);
2615                 if (rc) {
2616                         printk(KERN_WARNING
2617                                 "%s: security_transition_sid failed, rc=%d\n",
2618                                __func__, -rc);
2619                         return rc;
2620                 }
2621         }
2622
2623         return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2624 }
2625
2626 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2627                                        const struct qstr *qstr,
2628                                        const char **name,
2629                                        void **value, size_t *len)
2630 {
2631         const struct task_security_struct *tsec = current_security();
2632         struct inode_security_struct *dsec;
2633         struct superblock_security_struct *sbsec;
2634         u32 sid, newsid, clen;
2635         int rc;
2636         char *context;
2637
2638         dsec = dir->i_security;
2639         sbsec = dir->i_sb->s_security;
2640
2641         sid = tsec->sid;
2642         newsid = tsec->create_sid;
2643
2644         if ((sbsec->flags & SE_SBINITIALIZED) &&
2645             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2646                 newsid = sbsec->mntpoint_sid;
2647         else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2648                 rc = security_transition_sid(sid, dsec->sid,
2649                                              inode_mode_to_security_class(inode->i_mode),
2650                                              qstr, &newsid);
2651                 if (rc) {
2652                         printk(KERN_WARNING "%s:  "
2653                                "security_transition_sid failed, rc=%d (dev=%s "
2654                                "ino=%ld)\n",
2655                                __func__,
2656                                -rc, inode->i_sb->s_id, inode->i_ino);
2657                         return rc;
2658                 }
2659         }
2660
2661         /* Possibly defer initialization to selinux_complete_init. */
2662         if (sbsec->flags & SE_SBINITIALIZED) {
2663                 struct inode_security_struct *isec = inode->i_security;
2664                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2665                 isec->sid = newsid;
2666                 isec->initialized = 1;
2667         }
2668
2669         if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2670                 return -EOPNOTSUPP;
2671
2672         if (name)
2673                 *name = XATTR_SELINUX_SUFFIX;
2674
2675         if (value && len) {
2676                 rc = security_sid_to_context_force(newsid, &context, &clen);
2677                 if (rc)
2678                         return rc;
2679                 *value = context;
2680                 *len = clen;
2681         }
2682
2683         return 0;
2684 }
2685
2686 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2687 {
2688         return may_create(dir, dentry, SECCLASS_FILE);
2689 }
2690
2691 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2692 {
2693         return may_link(dir, old_dentry, MAY_LINK);
2694 }
2695
2696 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2697 {
2698         return may_link(dir, dentry, MAY_UNLINK);
2699 }
2700
2701 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2702 {
2703         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2704 }
2705
2706 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2707 {
2708         return may_create(dir, dentry, SECCLASS_DIR);
2709 }
2710
2711 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2712 {
2713         return may_link(dir, dentry, MAY_RMDIR);
2714 }
2715
2716 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2717 {
2718         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2719 }
2720
2721 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2722                                 struct inode *new_inode, struct dentry *new_dentry)
2723 {
2724         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2725 }
2726
2727 static int selinux_inode_readlink(struct dentry *dentry)
2728 {
2729         const struct cred *cred = current_cred();
2730
2731         return dentry_has_perm(cred, dentry, FILE__READ);
2732 }
2733
2734 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2735 {
2736         const struct cred *cred = current_cred();
2737
2738         return dentry_has_perm(cred, dentry, FILE__READ);
2739 }
2740
2741 static noinline int audit_inode_permission(struct inode *inode,
2742                                            u32 perms, u32 audited, u32 denied,
2743                                            unsigned flags)
2744 {
2745         struct common_audit_data ad;
2746         struct inode_security_struct *isec = inode->i_security;
2747         int rc;
2748
2749         ad.type = LSM_AUDIT_DATA_INODE;
2750         ad.u.inode = inode;
2751
2752         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2753                             audited, denied, &ad, flags);
2754         if (rc)
2755                 return rc;
2756         return 0;
2757 }
2758
2759 static int selinux_inode_permission(struct inode *inode, int mask)
2760 {
2761         const struct cred *cred = current_cred();
2762         u32 perms;
2763         bool from_access;
2764         unsigned flags = mask & MAY_NOT_BLOCK;
2765         struct inode_security_struct *isec;
2766         u32 sid;
2767         struct av_decision avd;
2768         int rc, rc2;
2769         u32 audited, denied;
2770
2771         from_access = mask & MAY_ACCESS;
2772         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2773
2774         /* No permission to check.  Existence test. */
2775         if (!mask)
2776                 return 0;
2777
2778         validate_creds(cred);
2779
2780         if (unlikely(IS_PRIVATE(inode)))
2781                 return 0;
2782
2783         perms = file_mask_to_av(inode->i_mode, mask);
2784
2785         sid = cred_sid(cred);
2786         isec = inode->i_security;
2787
2788         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2789         audited = avc_audit_required(perms, &avd, rc,
2790                                      from_access ? FILE__AUDIT_ACCESS : 0,
2791                                      &denied);
2792         if (likely(!audited))
2793                 return rc;
2794
2795         rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2796         if (rc2)
2797                 return rc2;
2798         return rc;
2799 }
2800
2801 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2802 {
2803         const struct cred *cred = current_cred();
2804         unsigned int ia_valid = iattr->ia_valid;
2805         __u32 av = FILE__WRITE;
2806
2807         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2808         if (ia_valid & ATTR_FORCE) {
2809                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2810                               ATTR_FORCE);
2811                 if (!ia_valid)
2812                         return 0;
2813         }
2814
2815         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2816                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2817                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2818
2819         if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2820                 av |= FILE__OPEN;
2821
2822         return dentry_has_perm(cred, dentry, av);
2823 }
2824
2825 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2826 {
2827         const struct cred *cred = current_cred();
2828         struct path path;
2829
2830         path.dentry = dentry;
2831         path.mnt = mnt;
2832
2833         return path_has_perm(cred, &path, FILE__GETATTR);
2834 }
2835
2836 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2837 {
2838         const struct cred *cred = current_cred();
2839
2840         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2841                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2842                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2843                         if (!capable(CAP_SETFCAP))
2844                                 return -EPERM;
2845                 } else if (!capable(CAP_SYS_ADMIN)) {
2846                         /* A different attribute in the security namespace.
2847                            Restrict to administrator. */
2848                         return -EPERM;
2849                 }
2850         }
2851
2852         /* Not an attribute we recognize, so just check the
2853            ordinary setattr permission. */
2854         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2855 }
2856
2857 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2858                                   const void *value, size_t size, int flags)
2859 {
2860         struct inode *inode = dentry->d_inode;
2861         struct inode_security_struct *isec = inode->i_security;
2862         struct superblock_security_struct *sbsec;
2863         struct common_audit_data ad;
2864         u32 newsid, sid = current_sid();
2865         int rc = 0;
2866
2867         if (strcmp(name, XATTR_NAME_SELINUX))
2868                 return selinux_inode_setotherxattr(dentry, name);
2869
2870         sbsec = inode->i_sb->s_security;
2871         if (!(sbsec->flags & SBLABEL_MNT))
2872                 return -EOPNOTSUPP;
2873
2874         if (!inode_owner_or_capable(inode))
2875                 return -EPERM;
2876
2877         ad.type = LSM_AUDIT_DATA_DENTRY;
2878         ad.u.dentry = dentry;
2879
2880         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2881                           FILE__RELABELFROM, &ad);
2882         if (rc)
2883                 return rc;
2884
2885         rc = security_context_to_sid(value, size, &newsid);
2886         if (rc == -EINVAL) {
2887                 if (!capable(CAP_MAC_ADMIN)) {
2888                         struct audit_buffer *ab;
2889                         size_t audit_size;
2890                         const char *str;
2891
2892                         /* We strip a nul only if it is at the end, otherwise the
2893                          * context contains a nul and we should audit that */
2894                         if (value) {
2895                                 str = value;
2896                                 if (str[size - 1] == '\0')
2897                                         audit_size = size - 1;
2898                                 else
2899                                         audit_size = size;
2900                         } else {
2901                                 str = "";
2902                                 audit_size = 0;
2903                         }
2904                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2905                         audit_log_format(ab, "op=setxattr invalid_context=");
2906                         audit_log_n_untrustedstring(ab, value, audit_size);
2907                         audit_log_end(ab);
2908
2909                         return rc;
2910                 }
2911                 rc = security_context_to_sid_force(value, size, &newsid);
2912         }
2913         if (rc)
2914                 return rc;
2915
2916         rc = avc_has_perm(sid, newsid, isec->sclass,
2917                           FILE__RELABELTO, &ad);
2918         if (rc)
2919                 return rc;
2920
2921         rc = security_validate_transition(isec->sid, newsid, sid,
2922                                           isec->sclass);
2923         if (rc)
2924                 return rc;
2925
2926         return avc_has_perm(newsid,
2927                             sbsec->sid,
2928                             SECCLASS_FILESYSTEM,
2929                             FILESYSTEM__ASSOCIATE,
2930                             &ad);
2931 }
2932
2933 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2934                                         const void *value, size_t size,
2935                                         int flags)
2936 {
2937         struct inode *inode = dentry->d_inode;
2938         struct inode_security_struct *isec = inode->i_security;
2939         u32 newsid;
2940         int rc;
2941
2942         if (strcmp(name, XATTR_NAME_SELINUX)) {
2943                 /* Not an attribute we recognize, so nothing to do. */
2944                 return;
2945         }
2946
2947         rc = security_context_to_sid_force(value, size, &newsid);
2948         if (rc) {
2949                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2950                        "for (%s, %lu), rc=%d\n",
2951                        inode->i_sb->s_id, inode->i_ino, -rc);
2952                 return;
2953         }
2954
2955         isec->sclass = inode_mode_to_security_class(inode->i_mode);
2956         isec->sid = newsid;
2957         isec->initialized = 1;
2958
2959         return;
2960 }
2961
2962 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2963 {
2964         const struct cred *cred = current_cred();
2965
2966         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2967 }
2968
2969 static int selinux_inode_listxattr(struct dentry *dentry)
2970 {
2971         const struct cred *cred = current_cred();
2972
2973         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2974 }
2975
2976 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2977 {
2978         if (strcmp(name, XATTR_NAME_SELINUX))
2979                 return selinux_inode_setotherxattr(dentry, name);
2980
2981         /* No one is allowed to remove a SELinux security label.
2982            You can change the label, but all data must be labeled. */
2983         return -EACCES;
2984 }
2985
2986 /*
2987  * Copy the inode security context value to the user.
2988  *
2989  * Permission check is handled by selinux_inode_getxattr hook.
2990  */
2991 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2992 {
2993         u32 size;
2994         int error;
2995         char *context = NULL;
2996         struct inode_security_struct *isec = inode->i_security;
2997
2998         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2999                 return -EOPNOTSUPP;
3000
3001         /*
3002          * If the caller has CAP_MAC_ADMIN, then get the raw context
3003          * value even if it is not defined by current policy; otherwise,
3004          * use the in-core value under current policy.
3005          * Use the non-auditing forms of the permission checks since
3006          * getxattr may be called by unprivileged processes commonly
3007          * and lack of permission just means that we fall back to the
3008          * in-core context value, not a denial.
3009          */
3010         error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3011                                 SECURITY_CAP_NOAUDIT);
3012         if (!error)
3013                 error = security_sid_to_context_force(isec->sid, &context,
3014                                                       &size);
3015         else
3016                 error = security_sid_to_context(isec->sid, &context, &size);
3017         if (error)
3018                 return error;
3019         error = size;
3020         if (alloc) {
3021                 *buffer = context;
3022                 goto out_nofree;
3023         }
3024         kfree(context);
3025 out_nofree:
3026         return error;
3027 }
3028
3029 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3030                                      const void *value, size_t size, int flags)
3031 {
3032         struct inode_security_struct *isec = inode->i_security;
3033         u32 newsid;
3034         int rc;
3035
3036         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3037                 return -EOPNOTSUPP;
3038
3039         if (!value || !size)
3040                 return -EACCES;
3041
3042         rc = security_context_to_sid((void *)value, size, &newsid);
3043         if (rc)
3044                 return rc;
3045
3046         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3047         isec->sid = newsid;
3048         isec->initialized = 1;
3049         return 0;
3050 }
3051
3052 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3053 {
3054         const int len = sizeof(XATTR_NAME_SELINUX);
3055         if (buffer && len <= buffer_size)
3056                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3057         return len;
3058 }
3059
3060 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
3061 {
3062         struct inode_security_struct *isec = inode->i_security;
3063         *secid = isec->sid;
3064 }
3065
3066 /* file security operations */
3067
3068 static int selinux_revalidate_file_permission(struct file *file, int mask)
3069 {
3070         const struct cred *cred = current_cred();
3071         struct inode *inode = file_inode(file);
3072
3073         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3074         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3075                 mask |= MAY_APPEND;
3076
3077         return file_has_perm(cred, file,
3078                              file_mask_to_av(inode->i_mode, mask));
3079 }
3080
3081 static int selinux_file_permission(struct file *file, int mask)
3082 {
3083         struct inode *inode = file_inode(file);
3084         struct file_security_struct *fsec = file->f_security;
3085         struct inode_security_struct *isec = inode->i_security;
3086         u32 sid = current_sid();
3087
3088         if (!mask)
3089                 /* No permission to check.  Existence test. */
3090                 return 0;
3091
3092         if (sid == fsec->sid && fsec->isid == isec->sid &&
3093             fsec->pseqno == avc_policy_seqno())
3094                 /* No change since file_open check. */
3095                 return 0;
3096
3097         return selinux_revalidate_file_permission(file, mask);
3098 }
3099
3100 static int selinux_file_alloc_security(struct file *file)
3101 {
3102         return file_alloc_security(file);
3103 }
3104
3105 static void selinux_file_free_security(struct file *file)
3106 {
3107         file_free_security(file);
3108 }
3109
3110 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3111                               unsigned long arg)
3112 {
3113         const struct cred *cred = current_cred();
3114         int error = 0;
3115
3116         switch (cmd) {
3117         case FIONREAD:
3118         /* fall through */
3119         case FIBMAP:
3120         /* fall through */
3121         case FIGETBSZ:
3122         /* fall through */
3123         case FS_IOC_GETFLAGS:
3124         /* fall through */
3125         case FS_IOC_GETVERSION:
3126                 error = file_has_perm(cred, file, FILE__GETATTR);
3127                 break;
3128
3129         case FS_IOC_SETFLAGS:
3130         /* fall through */
3131         case FS_IOC_SETVERSION:
3132                 error = file_has_perm(cred, file, FILE__SETATTR);
3133                 break;
3134
3135         /* sys_ioctl() checks */
3136         case FIONBIO:
3137         /* fall through */
3138         case FIOASYNC:
3139                 error = file_has_perm(cred, file, 0);
3140                 break;
3141
3142         case KDSKBENT:
3143         case KDSKBSENT:
3144                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3145                                             SECURITY_CAP_AUDIT);
3146                 break;
3147
3148         /* default case assumes that the command will go
3149          * to the file's ioctl() function.
3150          */
3151         default:
3152                 error = file_has_perm(cred, file, FILE__IOCTL);
3153         }
3154         return error;
3155 }
3156
3157 static int default_noexec;
3158
3159 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3160 {
3161         const struct cred *cred = current_cred();
3162         int rc = 0;
3163
3164         if (default_noexec &&
3165             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3166                 /*
3167                  * We are making executable an anonymous mapping or a
3168                  * private file mapping that will also be writable.
3169                  * This has an additional check.
3170                  */
3171                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3172                 if (rc)
3173                         goto error;
3174         }
3175
3176         if (file) {
3177                 /* read access is always possible with a mapping */
3178                 u32 av = FILE__READ;
3179
3180                 /* write access only matters if the mapping is shared */
3181                 if (shared && (prot & PROT_WRITE))
3182                         av |= FILE__WRITE;
3183
3184                 if (prot & PROT_EXEC)
3185                         av |= FILE__EXECUTE;
3186
3187                 return file_has_perm(cred, file, av);
3188         }
3189
3190 error:
3191         return rc;
3192 }
3193
3194 static int selinux_mmap_addr(unsigned long addr)
3195 {
3196         int rc = 0;
3197         u32 sid = current_sid();
3198
3199         /*
3200          * notice that we are intentionally putting the SELinux check before
3201          * the secondary cap_file_mmap check.  This is such a likely attempt
3202          * at bad behaviour/exploit that we always want to get the AVC, even
3203          * if DAC would have also denied the operation.
3204          */
3205         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3206                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3207                                   MEMPROTECT__MMAP_ZERO, NULL);
3208                 if (rc)
3209                         return rc;
3210         }
3211
3212         /* do DAC check on address space usage */
3213         return cap_mmap_addr(addr);
3214 }
3215
3216 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3217                              unsigned long prot, unsigned long flags)
3218 {
3219         if (selinux_checkreqprot)
3220                 prot = reqprot;
3221
3222         return file_map_prot_check(file, prot,
3223                                    (flags & MAP_TYPE) == MAP_SHARED);
3224 }
3225
3226 static int selinux_file_mprotect(struct vm_area_struct *vma,
3227                                  unsigned long reqprot,
3228                                  unsigned long prot)
3229 {
3230         const struct cred *cred = current_cred();
3231
3232         if (selinux_checkreqprot)
3233                 prot = reqprot;
3234
3235         if (default_noexec &&
3236             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3237                 int rc = 0;
3238                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3239                     vma->vm_end <= vma->vm_mm->brk) {
3240                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3241                 } else if (!vma->vm_file &&
3242                            vma->vm_start <= vma->vm_mm->start_stack &&
3243                            vma->vm_end >= vma->vm_mm->start_stack) {
3244                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3245                 } else if (vma->vm_file && vma->anon_vma) {
3246                         /*
3247                          * We are making executable a file mapping that has
3248                          * had some COW done. Since pages might have been
3249                          * written, check ability to execute the possibly
3250                          * modified content.  This typically should only
3251                          * occur for text relocations.
3252                          */
3253                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3254                 }
3255                 if (rc)
3256                         return rc;
3257         }
3258
3259         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3260 }
3261
3262 static int selinux_file_lock(struct file *file, unsigned int cmd)
3263 {
3264         const struct cred *cred = current_cred();
3265
3266         return file_has_perm(cred, file, FILE__LOCK);
3267 }
3268
3269 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3270                               unsigned long arg)
3271 {
3272         const struct cred *cred = current_cred();
3273         int err = 0;
3274
3275         switch (cmd) {
3276         case F_SETFL:
3277                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3278                         err = file_has_perm(cred, file, FILE__WRITE);
3279                         break;
3280                 }
3281                 /* fall through */
3282         case F_SETOWN:
3283         case F_SETSIG:
3284         case F_GETFL:
3285         case F_GETOWN:
3286         case F_GETSIG:
3287         case F_GETOWNER_UIDS:
3288                 /* Just check FD__USE permission */
3289                 err = file_has_perm(cred, file, 0);
3290                 break;
3291         case F_GETLK:
3292         case F_SETLK:
3293         case F_SETLKW:
3294 #if BITS_PER_LONG == 32
3295         case F_GETLK64:
3296         case F_SETLK64:
3297         case F_SETLKW64:
3298 #endif
3299                 err = file_has_perm(cred, file, FILE__LOCK);
3300                 break;
3301         }
3302
3303         return err;
3304 }
3305
3306 static int selinux_file_set_fowner(struct file *file)
3307 {
3308         struct file_security_struct *fsec;
3309
3310         fsec = file->f_security;
3311         fsec->fown_sid = current_sid();
3312
3313         return 0;
3314 }
3315
3316 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3317                                        struct fown_struct *fown, int signum)
3318 {
3319         struct file *file;
3320         u32 sid = task_sid(tsk);
3321         u32 perm;
3322         struct file_security_struct *fsec;
3323
3324         /* struct fown_struct is never outside the context of a struct file */
3325         file = container_of(fown, struct file, f_owner);
3326
3327         fsec = file->f_security;
3328
3329         if (!signum)
3330                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3331         else
3332                 perm = signal_to_av(signum);
3333
3334         return avc_has_perm(fsec->fown_sid, sid,
3335                             SECCLASS_PROCESS, perm, NULL);
3336 }
3337
3338 static int selinux_file_receive(struct file *file)
3339 {
3340         const struct cred *cred = current_cred();
3341
3342         return file_has_perm(cred, file, file_to_av(file));
3343 }
3344
3345 static int selinux_file_open(struct file *file, const struct cred *cred)
3346 {
3347         struct file_security_struct *fsec;
3348         struct inode_security_struct *isec;
3349
3350         fsec = file->f_security;
3351         isec = file_inode(file)->i_security;
3352         /*
3353          * Save inode label and policy sequence number
3354          * at open-time so that selinux_file_permission
3355          * can determine whether revalidation is necessary.
3356          * Task label is already saved in the file security
3357          * struct as its SID.
3358          */
3359         fsec->isid = isec->sid;
3360         fsec->pseqno = avc_policy_seqno();
3361         /*
3362          * Since the inode label or policy seqno may have changed
3363          * between the selinux_inode_permission check and the saving
3364          * of state above, recheck that access is still permitted.
3365          * Otherwise, access might never be revalidated against the
3366          * new inode label or new policy.
3367          * This check is not redundant - do not remove.
3368          */
3369         return file_path_has_perm(cred, file, open_file_to_av(file));
3370 }
3371
3372 /* task security operations */
3373
3374 static int selinux_task_create(unsigned long clone_flags)
3375 {
3376         return current_has_perm(current, PROCESS__FORK);
3377 }
3378
3379 /*
3380  * allocate the SELinux part of blank credentials
3381  */
3382 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3383 {
3384         struct task_security_struct *tsec;
3385
3386         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3387         if (!tsec)
3388                 return -ENOMEM;
3389
3390         cred->security = tsec;
3391         return 0;
3392 }
3393
3394 /*
3395  * detach and free the LSM part of a set of credentials
3396  */
3397 static void selinux_cred_free(struct cred *cred)
3398 {
3399         struct task_security_struct *tsec = cred->security;
3400
3401         /*
3402          * cred->security == NULL if security_cred_alloc_blank() or
3403          * security_prepare_creds() returned an error.
3404          */
3405         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3406         cred->security = (void *) 0x7UL;
3407         kfree(tsec);
3408 }
3409
3410 /*
3411  * prepare a new set of credentials for modification
3412  */
3413 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3414                                 gfp_t gfp)
3415 {
3416         const struct task_security_struct *old_tsec;
3417         struct task_security_struct *tsec;
3418
3419         old_tsec = old->security;
3420
3421         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3422         if (!tsec)
3423                 return -ENOMEM;
3424
3425         new->security = tsec;
3426         return 0;
3427 }
3428
3429 /*
3430  * transfer the SELinux data to a blank set of creds
3431  */
3432 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3433 {
3434         const struct task_security_struct *old_tsec = old->security;
3435         struct task_security_struct *tsec = new->security;
3436
3437         *tsec = *old_tsec;
3438 }
3439
3440 /*
3441  * set the security data for a kernel service
3442  * - all the creation contexts are set to unlabelled
3443  */
3444 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3445 {
3446         struct task_security_struct *tsec = new->security;
3447         u32 sid = current_sid();
3448         int ret;
3449
3450         ret = avc_has_perm(sid, secid,
3451                            SECCLASS_KERNEL_SERVICE,
3452                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3453                            NULL);
3454         if (ret == 0) {
3455                 tsec->sid = secid;
3456                 tsec->create_sid = 0;
3457                 tsec->keycreate_sid = 0;
3458                 tsec->sockcreate_sid = 0;
3459         }
3460         return ret;
3461 }
3462
3463 /*
3464  * set the file creation context in a security record to the same as the
3465  * objective context of the specified inode
3466  */
3467 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3468 {
3469         struct inode_security_struct *isec = inode->i_security;
3470         struct task_security_struct *tsec = new->security;
3471         u32 sid = current_sid();
3472         int ret;
3473
3474         ret = avc_has_perm(sid, isec->sid,
3475                            SECCLASS_KERNEL_SERVICE,
3476                            KERNEL_SERVICE__CREATE_FILES_AS,
3477                            NULL);
3478
3479         if (ret == 0)
3480                 tsec->create_sid = isec->sid;
3481         return ret;
3482 }
3483
3484 static int selinux_kernel_module_request(char *kmod_name)
3485 {
3486         u32 sid;
3487         struct common_audit_data ad;
3488
3489         sid = task_sid(current);
3490
3491         ad.type = LSM_AUDIT_DATA_KMOD;
3492         ad.u.kmod_name = kmod_name;
3493
3494         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3495                             SYSTEM__MODULE_REQUEST, &ad);
3496 }
3497
3498 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3499 {
3500         return current_has_perm(p, PROCESS__SETPGID);
3501 }
3502
3503 static int selinux_task_getpgid(struct task_struct *p)
3504 {
3505         return current_has_perm(p, PROCESS__GETPGID);
3506 }
3507
3508 static int selinux_task_getsid(struct task_struct *p)
3509 {
3510         return current_has_perm(p, PROCESS__GETSESSION);
3511 }
3512
3513 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3514 {
3515         *secid = task_sid(p);
3516 }
3517
3518 static int selinux_task_setnice(struct task_struct *p, int nice)
3519 {
3520         int rc;
3521
3522         rc = cap_task_setnice(p, nice);
3523         if (rc)
3524                 return rc;
3525
3526         return current_has_perm(p, PROCESS__SETSCHED);
3527 }
3528
3529 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3530 {
3531         int rc;
3532
3533         rc = cap_task_setioprio(p, ioprio);
3534         if (rc)
3535                 return rc;
3536
3537         return current_has_perm(p, PROCESS__SETSCHED);
3538 }
3539
3540 static int selinux_task_getioprio(struct task_struct *p)
3541 {
3542         return current_has_perm(p, PROCESS__GETSCHED);
3543 }
3544
3545 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3546                 struct rlimit *new_rlim)
3547 {
3548         struct rlimit *old_rlim = p->signal->rlim + resource;
3549
3550         /* Control the ability to change the hard limit (whether
3551            lowering or raising it), so that the hard limit can
3552            later be used as a safe reset point for the soft limit
3553            upon context transitions.  See selinux_bprm_committing_creds. */
3554         if (old_rlim->rlim_max != new_rlim->rlim_max)
3555                 return current_has_perm(p, PROCESS__SETRLIMIT);
3556
3557         return 0;
3558 }
3559
3560 static int selinux_task_setscheduler(struct task_struct *p)
3561 {
3562         int rc;
3563
3564         rc = cap_task_setscheduler(p);
3565         if (rc)
3566                 return rc;
3567
3568         return current_has_perm(p, PROCESS__SETSCHED);
3569 }
3570
3571 static int selinux_task_getscheduler(struct task_struct *p)
3572 {
3573         return current_has_perm(p, PROCESS__GETSCHED);
3574 }
3575
3576 static int selinux_task_movememory(struct task_struct *p)
3577 {
3578         return current_has_perm(p, PROCESS__SETSCHED);
3579 }
3580
3581 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3582                                 int sig, u32 secid)
3583 {
3584         u32 perm;
3585         int rc;
3586
3587         if (!sig)
3588                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3589         else
3590                 perm = signal_to_av(sig);
3591         if (secid)
3592                 rc = avc_has_perm(secid, task_sid(p),
3593                                   SECCLASS_PROCESS, perm, NULL);
3594         else
3595                 rc = current_has_perm(p, perm);
3596         return rc;
3597 }
3598
3599 static int selinux_task_wait(struct task_struct *p)
3600 {
3601         return task_has_perm(p, current, PROCESS__SIGCHLD);
3602 }
3603
3604 static void selinux_task_to_inode(struct task_struct *p,
3605                                   struct inode *inode)
3606 {
3607         struct inode_security_struct *isec = inode->i_security;
3608         u32 sid = task_sid(p);
3609
3610         isec->sid = sid;
3611         isec->initialized = 1;
3612 }
3613
3614 /* Returns error only if unable to parse addresses */
3615 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3616                         struct common_audit_data *ad, u8 *proto)
3617 {
3618         int offset, ihlen, ret = -EINVAL;
3619         struct iphdr _iph, *ih;
3620
3621         offset = skb_network_offset(skb);
3622         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3623         if (ih == NULL)
3624                 goto out;
3625
3626         ihlen = ih->ihl * 4;
3627         if (ihlen < sizeof(_iph))
3628                 goto out;
3629
3630         ad->u.net->v4info.saddr = ih->saddr;
3631         ad->u.net->v4info.daddr = ih->daddr;
3632         ret = 0;
3633
3634         if (proto)
3635                 *proto = ih->protocol;
3636
3637         switch (ih->protocol) {
3638         case IPPROTO_TCP: {
3639                 struct tcphdr _tcph, *th;
3640
3641                 if (ntohs(ih->frag_off) & IP_OFFSET)
3642                         break;
3643
3644                 offset += ihlen;
3645                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3646                 if (th == NULL)
3647                         break;
3648
3649                 ad->u.net->sport = th->source;
3650                 ad->u.net->dport = th->dest;
3651                 break;
3652         }
3653
3654         case IPPROTO_UDP: {
3655                 struct udphdr _udph, *uh;
3656
3657                 if (ntohs(ih->frag_off) & IP_OFFSET)
3658                         break;
3659
3660                 offset += ihlen;
3661                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3662                 if (uh == NULL)
3663                         break;
3664
3665                 ad->u.net->sport = uh->source;
3666                 ad->u.net->dport = uh->dest;
3667                 break;
3668         }
3669
3670         case IPPROTO_DCCP: {
3671                 struct dccp_hdr _dccph, *dh;
3672
3673                 if (ntohs(ih->frag_off) & IP_OFFSET)
3674                         break;
3675
3676                 offset += ihlen;
3677                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3678                 if (dh == NULL)
3679                         break;
3680
3681                 ad->u.net->sport = dh->dccph_sport;
3682                 ad->u.net->dport = dh->dccph_dport;
3683                 break;
3684         }
3685
3686         default:
3687                 break;
3688         }
3689 out:
3690         return ret;
3691 }
3692
3693 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3694
3695 /* Returns error only if unable to parse addresses */
3696 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3697                         struct common_audit_data *ad, u8 *proto)
3698 {
3699         u8 nexthdr;
3700         int ret = -EINVAL, offset;
3701         struct ipv6hdr _ipv6h, *ip6;
3702         __be16 frag_off;
3703
3704         offset = skb_network_offset(skb);
3705         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3706         if (ip6 == NULL)
3707                 goto out;
3708
3709         ad->u.net->v6info.saddr = ip6->saddr;
3710         ad->u.net->v6info.daddr = ip6->daddr;
3711         ret = 0;
3712
3713         nexthdr = ip6->nexthdr;
3714         offset += sizeof(_ipv6h);
3715         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3716         if (offset < 0)
3717                 goto out;
3718
3719         if (proto)
3720                 *proto = nexthdr;
3721
3722         switch (nexthdr) {
3723         case IPPROTO_TCP: {
3724                 struct tcphdr _tcph, *th;
3725
3726                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3727                 if (th == NULL)
3728                         break;
3729
3730                 ad->u.net->sport = th->source;
3731                 ad->u.net->dport = th->dest;
3732                 break;
3733         }
3734
3735         case IPPROTO_UDP: {
3736                 struct udphdr _udph, *uh;
3737
3738                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3739                 if (uh == NULL)
3740                         break;
3741
3742                 ad->u.net->sport = uh->source;
3743                 ad->u.net->dport = uh->dest;
3744                 break;
3745         }
3746
3747         case IPPROTO_DCCP: {
3748                 struct dccp_hdr _dccph, *dh;
3749
3750                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3751                 if (dh == NULL)
3752                         break;
3753
3754                 ad->u.net->sport = dh->dccph_sport;
3755                 ad->u.net->dport = dh->dccph_dport;
3756                 break;
3757         }
3758
3759         /* includes fragments */
3760         default:
3761                 break;
3762         }
3763 out:
3764         return ret;
3765 }
3766
3767 #endif /* IPV6 */
3768
3769 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3770                              char **_addrp, int src, u8 *proto)
3771 {
3772         char *addrp;
3773         int ret;
3774
3775         switch (ad->u.net->family) {
3776         case PF_INET:
3777                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3778                 if (ret)
3779                         goto parse_error;
3780                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3781                                        &ad->u.net->v4info.daddr);
3782                 goto okay;
3783
3784 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3785         case PF_INET6:
3786                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3787                 if (ret)
3788                         goto parse_error;
3789                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3790                                        &ad->u.net->v6info.daddr);
3791                 goto okay;
3792 #endif  /* IPV6 */
3793         default:
3794                 addrp = NULL;
3795                 goto okay;
3796         }
3797
3798 parse_error:
3799         printk(KERN_WARNING
3800                "SELinux: failure in selinux_parse_skb(),"
3801                " unable to parse packet\n");
3802         return ret;
3803
3804 okay:
3805         if (_addrp)
3806                 *_addrp = addrp;
3807         return 0;
3808 }
3809
3810 /**
3811  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3812  * @skb: the packet
3813  * @family: protocol family
3814  * @sid: the packet's peer label SID
3815  *
3816  * Description:
3817  * Check the various different forms of network peer labeling and determine
3818  * the peer label/SID for the packet; most of the magic actually occurs in
3819  * the security server function security_net_peersid_cmp().  The function
3820  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3821  * or -EACCES if @sid is invalid due to inconsistencies with the different
3822  * peer labels.
3823  *
3824  */
3825 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3826 {
3827         int err;
3828         u32 xfrm_sid;
3829         u32 nlbl_sid;
3830         u32 nlbl_type;
3831
3832         err = selinux_skb_xfrm_sid(skb, &xfrm_sid);
3833         if (unlikely(err))
3834                 return -EACCES;
3835         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3836         if (unlikely(err))
3837                 return -EACCES;
3838
3839         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3840         if (unlikely(err)) {
3841                 printk(KERN_WARNING
3842                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3843                        " unable to determine packet's peer label\n");
3844                 return -EACCES;
3845         }
3846
3847         return 0;
3848 }
3849
3850 /* socket security operations */
3851
3852 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3853                                  u16 secclass, u32 *socksid)
3854 {
3855         if (tsec->sockcreate_sid > SECSID_NULL) {
3856                 *socksid = tsec->sockcreate_sid;
3857                 return 0;
3858         }
3859
3860         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3861                                        socksid);
3862 }
3863
3864 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3865 {
3866         struct sk_security_struct *sksec = sk->sk_security;
3867         struct common_audit_data ad;
3868         struct lsm_network_audit net = {0,};
3869         u32 tsid = task_sid(task);
3870
3871         if (sksec->sid == SECINITSID_KERNEL)
3872                 return 0;
3873
3874         ad.type = LSM_AUDIT_DATA_NET;
3875         ad.u.net = &net;
3876         ad.u.net->sk = sk;
3877
3878         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3879 }
3880
3881 static int selinux_socket_create(int family, int type,
3882                                  int protocol, int kern)
3883 {
3884         const struct task_security_struct *tsec = current_security();
3885         u32 newsid;
3886         u16 secclass;
3887         int rc;
3888
3889         if (kern)
3890                 return 0;
3891
3892         secclass = socket_type_to_security_class(family, type, protocol);
3893         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3894         if (rc)
3895                 return rc;
3896
3897         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3898 }
3899
3900 static int selinux_socket_post_create(struct socket *sock, int family,
3901                                       int type, int protocol, int kern)
3902 {
3903         const struct task_security_struct *tsec = current_security();
3904         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3905         struct sk_security_struct *sksec;
3906         int err = 0;
3907
3908         isec->sclass = socket_type_to_security_class(family, type, protocol);
3909
3910         if (kern)
3911                 isec->sid = SECINITSID_KERNEL;
3912         else {
3913                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3914                 if (err)
3915                         return err;
3916         }
3917
3918         isec->initialized = 1;
3919
3920         if (sock->sk) {
3921                 sksec = sock->sk->sk_security;
3922                 sksec->sid = isec->sid;
3923                 sksec->sclass = isec->sclass;
3924                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3925         }
3926
3927         return err;
3928 }
3929
3930 /* Range of port numbers used to automatically bind.
3931    Need to determine whether we should perform a name_bind
3932    permission check between the socket and the port number. */
3933
3934 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3935 {
3936         struct sock *sk = sock->sk;
3937         u16 family;
3938         int err;
3939
3940         err = sock_has_perm(current, sk, SOCKET__BIND);
3941         if (err)
3942                 goto out;
3943
3944         /*
3945          * If PF_INET or PF_INET6, check name_bind permission for the port.
3946          * Multiple address binding for SCTP is not supported yet: we just
3947          * check the first address now.
3948          */
3949         family = sk->sk_family;
3950         if (family == PF_INET || family == PF_INET6) {
3951                 char *addrp;
3952                 struct sk_security_struct *sksec = sk->sk_security;
3953                 struct common_audit_data ad;
3954                 struct lsm_network_audit net = {0,};
3955                 struct sockaddr_in *addr4 = NULL;
3956                 struct sockaddr_in6 *addr6 = NULL;
3957                 unsigned short snum;
3958                 u32 sid, node_perm;
3959
3960                 if (family == PF_INET) {
3961                         addr4 = (struct sockaddr_in *)address;
3962                         snum = ntohs(addr4->sin_port);
3963                         addrp = (char *)&addr4->sin_addr.s_addr;
3964                 } else {
3965                         addr6 = (struct sockaddr_in6 *)address;
3966                         snum = ntohs(addr6->sin6_port);
3967                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3968                 }
3969
3970                 if (snum) {
3971                         int low, high;
3972
3973                         inet_get_local_port_range(&low, &high);
3974
3975                         if (snum < max(PROT_SOCK, low) || snum > high) {
3976                                 err = sel_netport_sid(sk->sk_protocol,
3977                                                       snum, &sid);
3978                                 if (err)
3979                                         goto out;
3980                                 ad.type = LSM_AUDIT_DATA_NET;
3981                                 ad.u.net = &net;
3982                                 ad.u.net->sport = htons(snum);
3983                                 ad.u.net->family = family;
3984                                 err = avc_has_perm(sksec->sid, sid,
3985                                                    sksec->sclass,
3986                                                    SOCKET__NAME_BIND, &ad);
3987                                 if (err)
3988                                         goto out;
3989                         }
3990                 }
3991
3992                 switch (sksec->sclass) {
3993                 case SECCLASS_TCP_SOCKET:
3994                         node_perm = TCP_SOCKET__NODE_BIND;
3995                         break;
3996
3997                 case SECCLASS_UDP_SOCKET:
3998                         node_perm = UDP_SOCKET__NODE_BIND;
3999                         break;
4000
4001                 case SECCLASS_DCCP_SOCKET:
4002                         node_perm = DCCP_SOCKET__NODE_BIND;
4003                         break;
4004
4005                 default:
4006                         node_perm = RAWIP_SOCKET__NODE_BIND;
4007                         break;
4008                 }
4009
4010                 err = sel_netnode_sid(addrp, family, &sid);
4011                 if (err)
4012                         goto out;
4013
4014                 ad.type = LSM_AUDIT_DATA_NET;
4015                 ad.u.net = &net;
4016                 ad.u.net->sport = htons(snum);
4017                 ad.u.net->family = family;
4018
4019                 if (family == PF_INET)
4020                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4021                 else
4022                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4023
4024                 err = avc_has_perm(sksec->sid, sid,
4025                                    sksec->sclass, node_perm, &ad);
4026                 if (err)
4027                         goto out;
4028         }
4029 out:
4030         return err;
4031 }
4032
4033 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4034 {
4035         struct sock *sk = sock->sk;
4036         struct sk_security_struct *sksec = sk->sk_security;
4037         int err;
4038
4039         err = sock_has_perm(current, sk, SOCKET__CONNECT);
4040         if (err)
4041                 return err;
4042
4043         /*
4044          * If a TCP or DCCP socket, check name_connect permission for the port.
4045          */
4046         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4047             sksec->sclass == SECCLASS_DCCP_SOCKET) {
4048                 struct common_audit_data ad;
4049                 struct lsm_network_audit net = {0,};
4050                 struct sockaddr_in *addr4 = NULL;
4051                 struct sockaddr_in6 *addr6 = NULL;
4052                 unsigned short snum;
4053                 u32 sid, perm;
4054
4055                 if (sk->sk_family == PF_INET) {
4056                         addr4 = (struct sockaddr_in *)address;
4057                         if (addrlen < sizeof(struct sockaddr_in))
4058                                 return -EINVAL;
4059                         snum = ntohs(addr4->sin_port);
4060                 } else {
4061                         addr6 = (struct sockaddr_in6 *)address;
4062                         if (addrlen < SIN6_LEN_RFC2133)
4063                                 return -EINVAL;
4064                         snum = ntohs(addr6->sin6_port);
4065                 }
4066
4067                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4068                 if (err)
4069                         goto out;
4070
4071                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4072                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4073
4074                 ad.type = LSM_AUDIT_DATA_NET;
4075                 ad.u.net = &net;
4076                 ad.u.net->dport = htons(snum);
4077                 ad.u.net->family = sk->sk_family;
4078                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4079                 if (err)
4080                         goto out;
4081         }
4082
4083         err = selinux_netlbl_socket_connect(sk, address);
4084
4085 out:
4086         return err;
4087 }
4088
4089 static int selinux_socket_listen(struct socket *sock, int backlog)
4090 {
4091         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4092 }
4093
4094 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4095 {
4096         int err;
4097         struct inode_security_struct *isec;
4098         struct inode_security_struct *newisec;
4099
4100         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4101         if (err)
4102                 return err;
4103
4104         newisec = SOCK_INODE(newsock)->i_security;
4105
4106         isec = SOCK_INODE(sock)->i_security;
4107         newisec->sclass = isec->sclass;
4108         newisec->sid = isec->sid;
4109         newisec->initialized = 1;
4110
4111         return 0;
4112 }
4113
4114 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4115                                   int size)
4116 {
4117         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4118 }
4119
4120 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4121                                   int size, int flags)
4122 {
4123         return sock_has_perm(current, sock->sk, SOCKET__READ);
4124 }
4125
4126 static int selinux_socket_getsockname(struct socket *sock)
4127 {
4128         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4129 }
4130
4131 static int selinux_socket_getpeername(struct socket *sock)
4132 {
4133         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4134 }
4135
4136 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4137 {
4138         int err;
4139
4140         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4141         if (err)
4142                 return err;
4143
4144         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4145 }
4146
4147 static int selinux_socket_getsockopt(struct socket *sock, int level,
4148                                      int optname)
4149 {
4150         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4151 }
4152
4153 static int selinux_socket_shutdown(struct socket *sock, int how)
4154 {
4155         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4156 }
4157
4158 static int selinux_socket_unix_stream_connect(struct sock *sock,
4159                                               struct sock *other,
4160                                               struct sock *newsk)
4161 {
4162         struct sk_security_struct *sksec_sock = sock->sk_security;
4163         struct sk_security_struct *sksec_other = other->sk_security;
4164         struct sk_security_struct *sksec_new = newsk->sk_security;
4165         struct common_audit_data ad;
4166         struct lsm_network_audit net = {0,};
4167         int err;
4168
4169         ad.type = LSM_AUDIT_DATA_NET;
4170         ad.u.net = &net;
4171         ad.u.net->sk = other;
4172
4173         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4174                            sksec_other->sclass,
4175                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4176         if (err)
4177                 return err;
4178
4179         /* server child socket */
4180         sksec_new->peer_sid = sksec_sock->sid;
4181         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4182                                     &sksec_new->sid);
4183         if (err)
4184                 return err;
4185
4186         /* connecting socket */
4187         sksec_sock->peer_sid = sksec_new->sid;
4188
4189         return 0;
4190 }
4191
4192 static int selinux_socket_unix_may_send(struct socket *sock,
4193                                         struct socket *other)
4194 {
4195         struct sk_security_struct *ssec = sock->sk->sk_security;
4196         struct sk_security_struct *osec = other->sk->sk_security;
4197         struct common_audit_data ad;
4198         struct lsm_network_audit net = {0,};
4199
4200         ad.type = LSM_AUDIT_DATA_NET;
4201         ad.u.net = &net;
4202         ad.u.net->sk = other->sk;
4203
4204         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4205                             &ad);
4206 }
4207
4208 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4209                                     u32 peer_sid,
4210                                     struct common_audit_data *ad)
4211 {
4212         int err;
4213         u32 if_sid;
4214         u32 node_sid;
4215
4216         err = sel_netif_sid(ifindex, &if_sid);
4217         if (err)
4218                 return err;
4219         err = avc_has_perm(peer_sid, if_sid,
4220                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4221         if (err)
4222                 return err;
4223
4224         err = sel_netnode_sid(addrp, family, &node_sid);
4225         if (err)
4226                 return err;
4227         return avc_has_perm(peer_sid, node_sid,
4228                             SECCLASS_NODE, NODE__RECVFROM, ad);
4229 }
4230
4231 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4232                                        u16 family)
4233 {
4234         int err = 0;
4235         struct sk_security_struct *sksec = sk->sk_security;
4236         u32 sk_sid = sksec->sid;
4237         struct common_audit_data ad;
4238         struct lsm_network_audit net = {0,};
4239         char *addrp;
4240
4241         ad.type = LSM_AUDIT_DATA_NET;
4242         ad.u.net = &net;
4243         ad.u.net->netif = skb->skb_iif;
4244         ad.u.net->family = family;
4245         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4246         if (err)
4247                 return err;
4248
4249         if (selinux_secmark_enabled()) {
4250                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4251                                    PACKET__RECV, &ad);
4252                 if (err)
4253                         return err;
4254         }
4255
4256         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4257         if (err)
4258                 return err;
4259         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4260
4261         return err;
4262 }
4263
4264 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4265 {
4266         int err;
4267         struct sk_security_struct *sksec = sk->sk_security;
4268         u16 family = sk->sk_family;
4269         u32 sk_sid = sksec->sid;
4270         struct common_audit_data ad;
4271         struct lsm_network_audit net = {0,};
4272         char *addrp;
4273         u8 secmark_active;
4274         u8 peerlbl_active;
4275
4276         if (family != PF_INET && family != PF_INET6)
4277                 return 0;
4278
4279         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4280         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4281                 family = PF_INET;
4282
4283         /* If any sort of compatibility mode is enabled then handoff processing
4284          * to the selinux_sock_rcv_skb_compat() function to deal with the
4285          * special handling.  We do this in an attempt to keep this function
4286          * as fast and as clean as possible. */
4287         if (!selinux_policycap_netpeer)
4288                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4289
4290         secmark_active = selinux_secmark_enabled();
4291         peerlbl_active = selinux_peerlbl_enabled();
4292         if (!secmark_active && !peerlbl_active)
4293                 return 0;
4294
4295         ad.type = LSM_AUDIT_DATA_NET;
4296         ad.u.net = &net;
4297         ad.u.net->netif = skb->skb_iif;
4298         ad.u.net->family = family;
4299         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4300         if (err)
4301                 return err;
4302
4303         if (peerlbl_active) {
4304                 u32 peer_sid;
4305
4306                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4307                 if (err)
4308                         return err;
4309                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4310                                                peer_sid, &ad);
4311                 if (err) {
4312                         selinux_netlbl_err(skb, err, 0);
4313                         return err;
4314                 }
4315                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4316                                    PEER__RECV, &ad);
4317                 if (err)
4318                         selinux_netlbl_err(skb, err, 0);
4319         }
4320
4321         if (secmark_active) {
4322                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4323                                    PACKET__RECV, &ad);
4324                 if (err)
4325                         return err;
4326         }
4327
4328         return err;
4329 }
4330
4331 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4332                                             int __user *optlen, unsigned len)
4333 {
4334         int err = 0;
4335         char *scontext;
4336         u32 scontext_len;
4337         struct sk_security_struct *sksec = sock->sk->sk_security;
4338         u32 peer_sid = SECSID_NULL;
4339
4340         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4341             sksec->sclass == SECCLASS_TCP_SOCKET)
4342                 peer_sid = sksec->peer_sid;
4343         if (peer_sid == SECSID_NULL)
4344                 return -ENOPROTOOPT;
4345
4346         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4347         if (err)
4348                 return err;
4349
4350         if (scontext_len > len) {
4351                 err = -ERANGE;
4352                 goto out_len;
4353         }
4354
4355         if (copy_to_user(optval, scontext, scontext_len))
4356                 err = -EFAULT;
4357
4358 out_len:
4359         if (put_user(scontext_len, optlen))
4360                 err = -EFAULT;
4361         kfree(scontext);
4362         return err;
4363 }
4364
4365 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4366 {
4367         u32 peer_secid = SECSID_NULL;
4368         u16 family;
4369
4370         if (skb && skb->protocol == htons(ETH_P_IP))
4371                 family = PF_INET;
4372         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4373                 family = PF_INET6;
4374         else if (sock)
4375                 family = sock->sk->sk_family;
4376         else
4377                 goto out;
4378
4379         if (sock && family == PF_UNIX)
4380                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4381         else if (skb)
4382                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4383
4384 out:
4385         *secid = peer_secid;
4386         if (peer_secid == SECSID_NULL)
4387                 return -EINVAL;
4388         return 0;
4389 }
4390
4391 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4392 {
4393         struct sk_security_struct *sksec;
4394
4395         sksec = kzalloc(sizeof(*sksec), priority);
4396         if (!sksec)
4397                 return -ENOMEM;
4398
4399         sksec->peer_sid = SECINITSID_UNLABELED;
4400         sksec->sid = SECINITSID_UNLABELED;
4401         selinux_netlbl_sk_security_reset(sksec);
4402         sk->sk_security = sksec;
4403
4404         return 0;
4405 }
4406
4407 static void selinux_sk_free_security(struct sock *sk)
4408 {
4409         struct sk_security_struct *sksec = sk->sk_security;
4410
4411         sk->sk_security = NULL;
4412         selinux_netlbl_sk_security_free(sksec);
4413         kfree(sksec);
4414 }
4415
4416 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4417 {
4418         struct sk_security_struct *sksec = sk->sk_security;
4419         struct sk_security_struct *newsksec = newsk->sk_security;
4420
4421         newsksec->sid = sksec->sid;
4422         newsksec->peer_sid = sksec->peer_sid;
4423         newsksec->sclass = sksec->sclass;
4424
4425         selinux_netlbl_sk_security_reset(newsksec);
4426 }
4427
4428 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4429 {
4430         if (!sk)
4431                 *secid = SECINITSID_ANY_SOCKET;
4432         else {
4433                 struct sk_security_struct *sksec = sk->sk_security;
4434
4435                 *secid = sksec->sid;
4436         }
4437 }
4438
4439 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4440 {
4441         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4442         struct sk_security_struct *sksec = sk->sk_security;
4443
4444         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4445             sk->sk_family == PF_UNIX)
4446                 isec->sid = sksec->sid;
4447         sksec->sclass = isec->sclass;
4448 }
4449
4450 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4451                                      struct request_sock *req)
4452 {
4453         struct sk_security_struct *sksec = sk->sk_security;
4454         int err;
4455         u16 family = sk->sk_family;
4456         u32 newsid;
4457         u32 peersid;
4458
4459         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4460         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4461                 family = PF_INET;
4462
4463         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4464         if (err)
4465                 return err;
4466         if (peersid == SECSID_NULL) {
4467                 req->secid = sksec->sid;
4468                 req->peer_secid = SECSID_NULL;
4469         } else {
4470                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4471                 if (err)
4472                         return err;
4473                 req->secid = newsid;
4474                 req->peer_secid = peersid;
4475         }
4476
4477         return selinux_netlbl_inet_conn_request(req, family);
4478 }
4479
4480 static void selinux_inet_csk_clone(struct sock *newsk,
4481                                    const struct request_sock *req)
4482 {
4483         struct sk_security_struct *newsksec = newsk->sk_security;
4484
4485         newsksec->sid = req->secid;
4486         newsksec->peer_sid = req->peer_secid;
4487         /* NOTE: Ideally, we should also get the isec->sid for the
4488            new socket in sync, but we don't have the isec available yet.
4489            So we will wait until sock_graft to do it, by which
4490            time it will have been created and available. */
4491
4492         /* We don't need to take any sort of lock here as we are the only
4493          * thread with access to newsksec */
4494         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4495 }
4496
4497 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4498 {
4499         u16 family = sk->sk_family;
4500         struct sk_security_struct *sksec = sk->sk_security;
4501
4502         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4503         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4504                 family = PF_INET;
4505
4506         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4507 }
4508
4509 static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4510 {
4511         skb_set_owner_w(skb, sk);
4512 }
4513
4514 static int selinux_secmark_relabel_packet(u32 sid)
4515 {
4516         const struct task_security_struct *__tsec;
4517         u32 tsid;
4518
4519         __tsec = current_security();
4520         tsid = __tsec->sid;
4521
4522         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4523 }
4524
4525 static void selinux_secmark_refcount_inc(void)
4526 {
4527         atomic_inc(&selinux_secmark_refcount);
4528 }
4529
4530 static void selinux_secmark_refcount_dec(void)
4531 {
4532         atomic_dec(&selinux_secmark_refcount);
4533 }
4534
4535 static void selinux_req_classify_flow(const struct request_sock *req,
4536                                       struct flowi *fl)
4537 {
4538         fl->flowi_secid = req->secid;
4539 }
4540
4541 static int selinux_tun_dev_alloc_security(void **security)
4542 {
4543         struct tun_security_struct *tunsec;
4544
4545         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4546         if (!tunsec)
4547                 return -ENOMEM;
4548         tunsec->sid = current_sid();
4549
4550         *security = tunsec;
4551         return 0;
4552 }
4553
4554 static void selinux_tun_dev_free_security(void *security)
4555 {
4556         kfree(security);
4557 }
4558
4559 static int selinux_tun_dev_create(void)
4560 {
4561         u32 sid = current_sid();
4562
4563         /* we aren't taking into account the "sockcreate" SID since the socket
4564          * that is being created here is not a socket in the traditional sense,
4565          * instead it is a private sock, accessible only to the kernel, and
4566          * representing a wide range of network traffic spanning multiple
4567          * connections unlike traditional sockets - check the TUN driver to
4568          * get a better understanding of why this socket is special */
4569
4570         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4571                             NULL);
4572 }
4573
4574 static int selinux_tun_dev_attach_queue(void *security)
4575 {
4576         struct tun_security_struct *tunsec = security;
4577
4578         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4579                             TUN_SOCKET__ATTACH_QUEUE, NULL);
4580 }
4581
4582 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4583 {
4584         struct tun_security_struct *tunsec = security;
4585         struct sk_security_struct *sksec = sk->sk_security;
4586
4587         /* we don't currently perform any NetLabel based labeling here and it
4588          * isn't clear that we would want to do so anyway; while we could apply
4589          * labeling without the support of the TUN user the resulting labeled
4590          * traffic from the other end of the connection would almost certainly
4591          * cause confusion to the TUN user that had no idea network labeling
4592          * protocols were being used */
4593
4594         sksec->sid = tunsec->sid;
4595         sksec->sclass = SECCLASS_TUN_SOCKET;
4596
4597         return 0;
4598 }
4599
4600 static int selinux_tun_dev_open(void *security)
4601 {
4602         struct tun_security_struct *tunsec = security;
4603         u32 sid = current_sid();
4604         int err;
4605
4606         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4607                            TUN_SOCKET__RELABELFROM, NULL);
4608         if (err)
4609                 return err;
4610         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4611                            TUN_SOCKET__RELABELTO, NULL);
4612         if (err)
4613                 return err;
4614         tunsec->sid = sid;
4615
4616         return 0;
4617 }
4618
4619 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4620 {
4621         int err = 0;
4622         u32 perm;
4623         struct nlmsghdr *nlh;
4624         struct sk_security_struct *sksec = sk->sk_security;
4625
4626         if (skb->len < NLMSG_HDRLEN) {
4627                 err = -EINVAL;
4628                 goto out;
4629         }
4630         nlh = nlmsg_hdr(skb);
4631
4632         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4633         if (err) {
4634                 if (err == -EINVAL) {
4635                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4636                                   "SELinux:  unrecognized netlink message"
4637                                   " type=%hu for sclass=%hu\n",
4638                                   nlh->nlmsg_type, sksec->sclass);
4639                         if (!selinux_enforcing || security_get_allow_unknown())
4640                                 err = 0;
4641                 }
4642
4643                 /* Ignore */
4644                 if (err == -ENOENT)
4645                         err = 0;
4646                 goto out;
4647         }
4648
4649         err = sock_has_perm(current, sk, perm);
4650 out:
4651         return err;
4652 }
4653
4654 #ifdef CONFIG_NETFILTER
4655
4656 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4657                                        u16 family)
4658 {
4659         int err;
4660         char *addrp;
4661         u32 peer_sid;
4662         struct common_audit_data ad;
4663         struct lsm_network_audit net = {0,};
4664         u8 secmark_active;
4665         u8 netlbl_active;
4666         u8 peerlbl_active;
4667
4668         if (!selinux_policycap_netpeer)
4669                 return NF_ACCEPT;
4670
4671         secmark_active = selinux_secmark_enabled();
4672         netlbl_active = netlbl_enabled();
4673         peerlbl_active = selinux_peerlbl_enabled();
4674         if (!secmark_active && !peerlbl_active)
4675                 return NF_ACCEPT;
4676
4677         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4678                 return NF_DROP;
4679
4680         ad.type = LSM_AUDIT_DATA_NET;
4681         ad.u.net = &net;
4682         ad.u.net->netif = ifindex;
4683         ad.u.net->family = family;
4684         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4685                 return NF_DROP;
4686
4687         if (peerlbl_active) {
4688                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4689                                                peer_sid, &ad);
4690                 if (err) {
4691                         selinux_netlbl_err(skb, err, 1);
4692                         return NF_DROP;
4693                 }
4694         }
4695
4696         if (secmark_active)
4697                 if (avc_has_perm(peer_sid, skb->secmark,
4698                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4699                         return NF_DROP;
4700
4701         if (netlbl_active)
4702                 /* we do this in the FORWARD path and not the POST_ROUTING
4703                  * path because we want to make sure we apply the necessary
4704                  * labeling before IPsec is applied so we can leverage AH
4705                  * protection */
4706                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4707                         return NF_DROP;
4708
4709         return NF_ACCEPT;
4710 }
4711
4712 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4713                                          struct sk_buff *skb,
4714                                          const struct net_device *in,
4715                                          const struct net_device *out,
4716                                          int (*okfn)(struct sk_buff *))
4717 {
4718         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4719 }
4720
4721 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4722 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4723                                          struct sk_buff *skb,
4724                                          const struct net_device *in,
4725                                          const struct net_device *out,
4726                                          int (*okfn)(struct sk_buff *))
4727 {
4728         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4729 }
4730 #endif  /* IPV6 */
4731
4732 static unsigned int selinux_ip_output(struct sk_buff *skb,
4733                                       u16 family)
4734 {
4735         struct sock *sk;
4736         u32 sid;
4737
4738         if (!netlbl_enabled())
4739                 return NF_ACCEPT;
4740
4741         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4742          * because we want to make sure we apply the necessary labeling
4743          * before IPsec is applied so we can leverage AH protection */
4744         sk = skb->sk;
4745         if (sk) {
4746                 struct sk_security_struct *sksec;
4747
4748                 if (sk->sk_state == TCP_LISTEN)
4749                         /* if the socket is the listening state then this
4750                          * packet is a SYN-ACK packet which means it needs to
4751                          * be labeled based on the connection/request_sock and
4752                          * not the parent socket.  unfortunately, we can't
4753                          * lookup the request_sock yet as it isn't queued on
4754                          * the parent socket until after the SYN-ACK is sent.
4755                          * the "solution" is to simply pass the packet as-is
4756                          * as any IP option based labeling should be copied
4757                          * from the initial connection request (in the IP
4758                          * layer).  it is far from ideal, but until we get a
4759                          * security label in the packet itself this is the
4760                          * best we can do. */
4761                         return NF_ACCEPT;
4762
4763                 /* standard practice, label using the parent socket */
4764                 sksec = sk->sk_security;
4765                 sid = sksec->sid;
4766         } else
4767                 sid = SECINITSID_KERNEL;
4768         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4769                 return NF_DROP;
4770
4771         return NF_ACCEPT;
4772 }
4773
4774 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4775                                         struct sk_buff *skb,
4776                                         const struct net_device *in,
4777                                         const struct net_device *out,
4778                                         int (*okfn)(struct sk_buff *))
4779 {
4780         return selinux_ip_output(skb, PF_INET);
4781 }
4782
4783 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4784                                                 int ifindex,
4785                                                 u16 family)
4786 {
4787         struct sock *sk = skb->sk;
4788         struct sk_security_struct *sksec;
4789         struct common_audit_data ad;
4790         struct lsm_network_audit net = {0,};
4791         char *addrp;
4792         u8 proto;
4793
4794         if (sk == NULL)
4795                 return NF_ACCEPT;
4796         sksec = sk->sk_security;
4797
4798         ad.type = LSM_AUDIT_DATA_NET;
4799         ad.u.net = &net;
4800         ad.u.net->netif = ifindex;
4801         ad.u.net->family = family;
4802         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4803                 return NF_DROP;
4804
4805         if (selinux_secmark_enabled())
4806                 if (avc_has_perm(sksec->sid, skb->secmark,
4807                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4808                         return NF_DROP_ERR(-ECONNREFUSED);
4809
4810         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4811                 return NF_DROP_ERR(-ECONNREFUSED);
4812
4813         return NF_ACCEPT;
4814 }
4815
4816 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4817                                          u16 family)
4818 {
4819         u32 secmark_perm;
4820         u32 peer_sid;
4821         struct sock *sk;
4822         struct common_audit_data ad;
4823         struct lsm_network_audit net = {0,};
4824         char *addrp;
4825         u8 secmark_active;
4826         u8 peerlbl_active;
4827
4828         /* If any sort of compatibility mode is enabled then handoff processing
4829          * to the selinux_ip_postroute_compat() function to deal with the
4830          * special handling.  We do this in an attempt to keep this function
4831          * as fast and as clean as possible. */
4832         if (!selinux_policycap_netpeer)
4833                 return selinux_ip_postroute_compat(skb, ifindex, family);
4834 #ifdef CONFIG_XFRM
4835         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4836          * packet transformation so allow the packet to pass without any checks
4837          * since we'll have another chance to perform access control checks
4838          * when the packet is on it's final way out.
4839          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4840          *       is NULL, in this case go ahead and apply access control. */
4841         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4842                 return NF_ACCEPT;
4843 #endif
4844         secmark_active = selinux_secmark_enabled();
4845         peerlbl_active = selinux_peerlbl_enabled();
4846         if (!secmark_active && !peerlbl_active)
4847                 return NF_ACCEPT;
4848
4849         /* if the packet is being forwarded then get the peer label from the
4850          * packet itself; otherwise check to see if it is from a local
4851          * application or the kernel, if from an application get the peer label
4852          * from the sending socket, otherwise use the kernel's sid */
4853         sk = skb->sk;
4854         if (sk == NULL) {
4855                 if (skb->skb_iif) {
4856                         secmark_perm = PACKET__FORWARD_OUT;
4857                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4858                                 return NF_DROP;
4859                 } else {
4860                         secmark_perm = PACKET__SEND;
4861                         peer_sid = SECINITSID_KERNEL;
4862                 }
4863         } else {
4864                 struct sk_security_struct *sksec = sk->sk_security;
4865                 peer_sid = sksec->sid;
4866                 secmark_perm = PACKET__SEND;
4867         }
4868
4869         ad.type = LSM_AUDIT_DATA_NET;
4870         ad.u.net = &net;
4871         ad.u.net->netif = ifindex;
4872         ad.u.net->family = family;
4873         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4874                 return NF_DROP;
4875
4876         if (secmark_active)
4877                 if (avc_has_perm(peer_sid, skb->secmark,
4878                                  SECCLASS_PACKET, secmark_perm, &ad))
4879                         return NF_DROP_ERR(-ECONNREFUSED);
4880
4881         if (peerlbl_active) {
4882                 u32 if_sid;
4883                 u32 node_sid;
4884
4885                 if (sel_netif_sid(ifindex, &if_sid))
4886                         return NF_DROP;
4887                 if (avc_has_perm(peer_sid, if_sid,
4888                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4889                         return NF_DROP_ERR(-ECONNREFUSED);
4890
4891                 if (sel_netnode_sid(addrp, family, &node_sid))
4892                         return NF_DROP;
4893                 if (avc_has_perm(peer_sid, node_sid,
4894                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4895                         return NF_DROP_ERR(-ECONNREFUSED);
4896         }
4897
4898         return NF_ACCEPT;
4899 }
4900
4901 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4902                                            struct sk_buff *skb,
4903                                            const struct net_device *in,
4904                                            const struct net_device *out,
4905                                            int (*okfn)(struct sk_buff *))
4906 {
4907         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4908 }
4909
4910 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4911 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4912                                            struct sk_buff *skb,
4913                                            const struct net_device *in,
4914                                            const struct net_device *out,
4915                                            int (*okfn)(struct sk_buff *))
4916 {
4917         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4918 }
4919 #endif  /* IPV6 */
4920
4921 #endif  /* CONFIG_NETFILTER */
4922
4923 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4924 {
4925         int err;
4926
4927         err = cap_netlink_send(sk, skb);
4928         if (err)
4929                 return err;
4930
4931         return selinux_nlmsg_perm(sk, skb);
4932 }
4933
4934 static int ipc_alloc_security(struct task_struct *task,
4935                               struct kern_ipc_perm *perm,
4936                               u16 sclass)
4937 {
4938         struct ipc_security_struct *isec;
4939         u32 sid;
4940
4941         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4942         if (!isec)
4943                 return -ENOMEM;
4944
4945         sid = task_sid(task);
4946         isec->sclass = sclass;
4947         isec->sid = sid;
4948         perm->security = isec;
4949
4950         return 0;
4951 }
4952
4953 static void ipc_free_security(struct kern_ipc_perm *perm)
4954 {
4955         struct ipc_security_struct *isec = perm->security;
4956         perm->security = NULL;
4957         kfree(isec);
4958 }
4959
4960 static int msg_msg_alloc_security(struct msg_msg *msg)
4961 {
4962         struct msg_security_struct *msec;
4963
4964         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4965         if (!msec)
4966                 return -ENOMEM;
4967
4968         msec->sid = SECINITSID_UNLABELED;
4969         msg->security = msec;
4970
4971         return 0;
4972 }
4973
4974 static void msg_msg_free_security(struct msg_msg *msg)
4975 {
4976         struct msg_security_struct *msec = msg->security;
4977
4978         msg->security = NULL;
4979         kfree(msec);
4980 }
4981
4982 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4983                         u32 perms)
4984 {
4985         struct ipc_security_struct *isec;
4986         struct common_audit_data ad;
4987         u32 sid = current_sid();
4988
4989         isec = ipc_perms->security;
4990
4991         ad.type = LSM_AUDIT_DATA_IPC;
4992         ad.u.ipc_id = ipc_perms->key;
4993
4994         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4995 }
4996
4997 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4998 {
4999         return msg_msg_alloc_security(msg);
5000 }
5001
5002 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5003 {
5004         msg_msg_free_security(msg);
5005 }
5006
5007 /* message queue security operations */
5008 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5009 {
5010         struct ipc_security_struct *isec;
5011         struct common_audit_data ad;
5012         u32 sid = current_sid();
5013         int rc;
5014
5015         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5016         if (rc)
5017                 return rc;
5018
5019         isec = msq->q_perm.security;
5020
5021         ad.type = LSM_AUDIT_DATA_IPC;
5022         ad.u.ipc_id = msq->q_perm.key;
5023
5024         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5025                           MSGQ__CREATE, &ad);
5026         if (rc) {
5027                 ipc_free_security(&msq->q_perm);
5028                 return rc;
5029         }
5030         return 0;
5031 }
5032
5033 static void selinux_msg_queue_free_security(struct msg_queue *msq)
5034 {
5035         ipc_free_security(&msq->q_perm);
5036 }
5037
5038 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5039 {
5040         struct ipc_security_struct *isec;
5041         struct common_audit_data ad;
5042         u32 sid = current_sid();
5043
5044         isec = msq->q_perm.security;
5045
5046         ad.type = LSM_AUDIT_DATA_IPC;
5047         ad.u.ipc_id = msq->q_perm.key;
5048
5049         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5050                             MSGQ__ASSOCIATE, &ad);
5051 }
5052
5053 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5054 {
5055         int err;
5056         int perms;
5057
5058         switch (cmd) {
5059         case IPC_INFO:
5060         case MSG_INFO:
5061                 /* No specific object, just general system-wide information. */
5062                 return task_has_system(current, SYSTEM__IPC_INFO);
5063         case IPC_STAT:
5064         case MSG_STAT:
5065                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5066                 break;
5067         case IPC_SET:
5068                 perms = MSGQ__SETATTR;
5069                 break;
5070         case IPC_RMID:
5071                 perms = MSGQ__DESTROY;
5072                 break;
5073         default:
5074                 return 0;
5075         }
5076
5077         err = ipc_has_perm(&msq->q_perm, perms);
5078         return err;
5079 }
5080
5081 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5082 {
5083         struct ipc_security_struct *isec;
5084         struct msg_security_struct *msec;
5085         struct common_audit_data ad;
5086         u32 sid = current_sid();
5087         int rc;
5088
5089         isec = msq->q_perm.security;
5090         msec = msg->security;
5091
5092         /*
5093          * First time through, need to assign label to the message
5094          */
5095         if (msec->sid == SECINITSID_UNLABELED) {
5096                 /*
5097                  * Compute new sid based on current process and
5098                  * message queue this message will be stored in
5099                  */
5100                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5101                                              NULL, &msec->sid);
5102                 if (rc)
5103                         return rc;
5104         }
5105
5106         ad.type = LSM_AUDIT_DATA_IPC;
5107         ad.u.ipc_id = msq->q_perm.key;
5108
5109         /* Can this process write to the queue? */
5110         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5111                           MSGQ__WRITE, &ad);
5112         if (!rc)
5113                 /* Can this process send the message */
5114                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5115                                   MSG__SEND, &ad);
5116         if (!rc)
5117                 /* Can the message be put in the queue? */
5118                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5119                                   MSGQ__ENQUEUE, &ad);
5120
5121         return rc;
5122 }
5123
5124 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5125                                     struct task_struct *target,
5126                                     long type, int mode)
5127 {
5128         struct ipc_security_struct *isec;
5129         struct msg_security_struct *msec;
5130         struct common_audit_data ad;
5131         u32 sid = task_sid(target);
5132         int rc;
5133
5134         isec = msq->q_perm.security;
5135         msec = msg->security;
5136
5137         ad.type = LSM_AUDIT_DATA_IPC;
5138         ad.u.ipc_id = msq->q_perm.key;
5139
5140         rc = avc_has_perm(sid, isec->sid,
5141                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5142         if (!rc)
5143                 rc = avc_has_perm(sid, msec->sid,
5144                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5145         return rc;
5146 }
5147
5148 /* Shared Memory security operations */
5149 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5150 {
5151         struct ipc_security_struct *isec;
5152         struct common_audit_data ad;
5153         u32 sid = current_sid();
5154         int rc;
5155
5156         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5157         if (rc)
5158                 return rc;
5159
5160         isec = shp->shm_perm.security;
5161
5162         ad.type = LSM_AUDIT_DATA_IPC;
5163         ad.u.ipc_id = shp->shm_perm.key;
5164
5165         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5166                           SHM__CREATE, &ad);
5167         if (rc) {
5168                 ipc_free_security(&shp->shm_perm);
5169                 return rc;
5170         }
5171         return 0;
5172 }
5173
5174 static void selinux_shm_free_security(struct shmid_kernel *shp)
5175 {
5176         ipc_free_security(&shp->shm_perm);
5177 }
5178
5179 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5180 {
5181         struct ipc_security_struct *isec;
5182         struct common_audit_data ad;
5183         u32 sid = current_sid();
5184
5185         isec = shp->shm_perm.security;
5186
5187         ad.type = LSM_AUDIT_DATA_IPC;
5188         ad.u.ipc_id = shp->shm_perm.key;
5189
5190         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5191                             SHM__ASSOCIATE, &ad);
5192 }
5193
5194 /* Note, at this point, shp is locked down */
5195 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5196 {
5197         int perms;
5198         int err;
5199
5200         switch (cmd) {
5201         case IPC_INFO:
5202         case SHM_INFO:
5203                 /* No specific object, just general system-wide information. */
5204                 return task_has_system(current, SYSTEM__IPC_INFO);
5205         case IPC_STAT:
5206         case SHM_STAT:
5207                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5208                 break;
5209         case IPC_SET:
5210                 perms = SHM__SETATTR;
5211                 break;
5212         case SHM_LOCK:
5213         case SHM_UNLOCK:
5214                 perms = SHM__LOCK;
5215                 break;
5216         case IPC_RMID:
5217                 perms = SHM__DESTROY;
5218                 break;
5219         default:
5220                 return 0;
5221         }
5222
5223         err = ipc_has_perm(&shp->shm_perm, perms);
5224         return err;
5225 }
5226
5227 static int selinux_shm_shmat(struct shmid_kernel *shp,
5228                              char __user *shmaddr, int shmflg)
5229 {
5230         u32 perms;
5231
5232         if (shmflg & SHM_RDONLY)
5233                 perms = SHM__READ;
5234         else
5235                 perms = SHM__READ | SHM__WRITE;
5236
5237         return ipc_has_perm(&shp->shm_perm, perms);
5238 }
5239
5240 /* Semaphore security operations */
5241 static int selinux_sem_alloc_security(struct sem_array *sma)
5242 {
5243         struct ipc_security_struct *isec;
5244         struct common_audit_data ad;
5245         u32 sid = current_sid();
5246         int rc;
5247
5248         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5249         if (rc)
5250                 return rc;
5251
5252         isec = sma->sem_perm.security;
5253
5254         ad.type = LSM_AUDIT_DATA_IPC;
5255         ad.u.ipc_id = sma->sem_perm.key;
5256
5257         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5258                           SEM__CREATE, &ad);
5259         if (rc) {
5260                 ipc_free_security(&sma->sem_perm);
5261                 return rc;
5262         }
5263         return 0;
5264 }
5265
5266 static void selinux_sem_free_security(struct sem_array *sma)
5267 {
5268         ipc_free_security(&sma->sem_perm);
5269 }
5270
5271 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5272 {
5273         struct ipc_security_struct *isec;
5274         struct common_audit_data ad;
5275         u32 sid = current_sid();
5276
5277         isec = sma->sem_perm.security;
5278
5279         ad.type = LSM_AUDIT_DATA_IPC;
5280         ad.u.ipc_id = sma->sem_perm.key;
5281
5282         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5283                             SEM__ASSOCIATE, &ad);
5284 }
5285
5286 /* Note, at this point, sma is locked down */
5287 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5288 {
5289         int err;
5290         u32 perms;
5291
5292         switch (cmd) {
5293         case IPC_INFO:
5294         case SEM_INFO:
5295                 /* No specific object, just general system-wide information. */
5296                 return task_has_system(current, SYSTEM__IPC_INFO);
5297         case GETPID:
5298         case GETNCNT:
5299         case GETZCNT:
5300                 perms = SEM__GETATTR;
5301                 break;
5302         case GETVAL:
5303         case GETALL:
5304                 perms = SEM__READ;
5305                 break;
5306         case SETVAL:
5307         case SETALL:
5308                 perms = SEM__WRITE;
5309                 break;
5310         case IPC_RMID:
5311                 perms = SEM__DESTROY;
5312                 break;
5313         case IPC_SET:
5314                 perms = SEM__SETATTR;
5315                 break;
5316         case IPC_STAT:
5317         case SEM_STAT:
5318                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5319                 break;
5320         default:
5321                 return 0;
5322         }
5323
5324         err = ipc_has_perm(&sma->sem_perm, perms);
5325         return err;
5326 }
5327
5328 static int selinux_sem_semop(struct sem_array *sma,
5329                              struct sembuf *sops, unsigned nsops, int alter)
5330 {
5331         u32 perms;
5332
5333         if (alter)
5334                 perms = SEM__READ | SEM__WRITE;
5335         else
5336                 perms = SEM__READ;
5337
5338         return ipc_has_perm(&sma->sem_perm, perms);
5339 }
5340
5341 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5342 {
5343         u32 av = 0;
5344
5345         av = 0;
5346         if (flag & S_IRUGO)
5347                 av |= IPC__UNIX_READ;
5348         if (flag & S_IWUGO)
5349                 av |= IPC__UNIX_WRITE;
5350
5351         if (av == 0)
5352                 return 0;
5353
5354         return ipc_has_perm(ipcp, av);
5355 }
5356
5357 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5358 {
5359         struct ipc_security_struct *isec = ipcp->security;
5360         *secid = isec->sid;
5361 }
5362
5363 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5364 {
5365         if (inode)
5366                 inode_doinit_with_dentry(inode, dentry);
5367 }
5368
5369 static int selinux_getprocattr(struct task_struct *p,
5370                                char *name, char **value)
5371 {
5372         const struct task_security_struct *__tsec;
5373         u32 sid;
5374         int error;
5375         unsigned len;
5376
5377         if (current != p) {
5378                 error = current_has_perm(p, PROCESS__GETATTR);
5379                 if (error)
5380                         return error;
5381         }
5382
5383         rcu_read_lock();
5384         __tsec = __task_cred(p)->security;
5385
5386         if (!strcmp(name, "current"))
5387                 sid = __tsec->sid;
5388         else if (!strcmp(name, "prev"))
5389                 sid = __tsec->osid;
5390         else if (!strcmp(name, "exec"))
5391                 sid = __tsec->exec_sid;
5392         else if (!strcmp(name, "fscreate"))
5393                 sid = __tsec->create_sid;
5394         else if (!strcmp(name, "keycreate"))
5395                 sid = __tsec->keycreate_sid;
5396         else if (!strcmp(name, "sockcreate"))
5397                 sid = __tsec->sockcreate_sid;
5398         else
5399                 goto invalid;
5400         rcu_read_unlock();
5401
5402         if (!sid)
5403                 return 0;
5404
5405         error = security_sid_to_context(sid, value, &len);
5406         if (error)
5407                 return error;
5408         return len;
5409
5410 invalid:
5411         rcu_read_unlock();
5412         return -EINVAL;
5413 }
5414
5415 static int selinux_setprocattr(struct task_struct *p,
5416                                char *name, void *value, size_t size)
5417 {
5418         struct task_security_struct *tsec;
5419         struct task_struct *tracer;
5420         struct cred *new;
5421         u32 sid = 0, ptsid;
5422         int error;
5423         char *str = value;
5424
5425         if (current != p) {
5426                 /* SELinux only allows a process to change its own
5427                    security attributes. */
5428                 return -EACCES;
5429         }
5430
5431         /*
5432          * Basic control over ability to set these attributes at all.
5433          * current == p, but we'll pass them separately in case the
5434          * above restriction is ever removed.
5435          */
5436         if (!strcmp(name, "exec"))
5437                 error = current_has_perm(p, PROCESS__SETEXEC);
5438         else if (!strcmp(name, "fscreate"))
5439                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5440         else if (!strcmp(name, "keycreate"))
5441                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5442         else if (!strcmp(name, "sockcreate"))
5443                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5444         else if (!strcmp(name, "current"))
5445                 error = current_has_perm(p, PROCESS__SETCURRENT);
5446         else
5447                 error = -EINVAL;
5448         if (error)
5449                 return error;
5450
5451         /* Obtain a SID for the context, if one was specified. */
5452         if (size && str[1] && str[1] != '\n') {
5453                 if (str[size-1] == '\n') {
5454                         str[size-1] = 0;
5455                         size--;
5456                 }
5457                 error = security_context_to_sid(value, size, &sid);
5458                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5459                         if (!capable(CAP_MAC_ADMIN)) {
5460                                 struct audit_buffer *ab;
5461                                 size_t audit_size;
5462
5463                                 /* We strip a nul only if it is at the end, otherwise the
5464                                  * context contains a nul and we should audit that */
5465                                 if (str[size - 1] == '\0')
5466                                         audit_size = size - 1;
5467                                 else
5468                                         audit_size = size;
5469                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5470                                 audit_log_format(ab, "op=fscreate invalid_context=");
5471                                 audit_log_n_untrustedstring(ab, value, audit_size);
5472                                 audit_log_end(ab);
5473
5474                                 return error;
5475                         }
5476                         error = security_context_to_sid_force(value, size,
5477                                                               &sid);
5478                 }
5479                 if (error)
5480                         return error;
5481         }
5482
5483         new = prepare_creds();
5484         if (!new)
5485                 return -ENOMEM;
5486
5487         /* Permission checking based on the specified context is
5488            performed during the actual operation (execve,
5489            open/mkdir/...), when we know the full context of the
5490            operation.  See selinux_bprm_set_creds for the execve
5491            checks and may_create for the file creation checks. The
5492            operation will then fail if the context is not permitted. */
5493         tsec = new->security;
5494         if (!strcmp(name, "exec")) {
5495                 tsec->exec_sid = sid;
5496         } else if (!strcmp(name, "fscreate")) {
5497                 tsec->create_sid = sid;
5498         } else if (!strcmp(name, "keycreate")) {
5499                 error = may_create_key(sid, p);
5500                 if (error)
5501                         goto abort_change;
5502                 tsec->keycreate_sid = sid;
5503         } else if (!strcmp(name, "sockcreate")) {
5504                 tsec->sockcreate_sid = sid;
5505         } else if (!strcmp(name, "current")) {
5506                 error = -EINVAL;
5507                 if (sid == 0)
5508                         goto abort_change;
5509
5510                 /* Only allow single threaded processes to change context */
5511                 error = -EPERM;
5512                 if (!current_is_single_threaded()) {
5513                         error = security_bounded_transition(tsec->sid, sid);
5514                         if (error)
5515                                 goto abort_change;
5516                 }
5517
5518                 /* Check permissions for the transition. */
5519                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5520                                      PROCESS__DYNTRANSITION, NULL);
5521                 if (error)
5522                         goto abort_change;
5523
5524                 /* Check for ptracing, and update the task SID if ok.
5525                    Otherwise, leave SID unchanged and fail. */
5526                 ptsid = 0;
5527                 task_lock(p);
5528                 tracer = ptrace_parent(p);
5529                 if (tracer)
5530                         ptsid = task_sid(tracer);
5531                 task_unlock(p);
5532
5533                 if (tracer) {
5534                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5535                                              PROCESS__PTRACE, NULL);
5536                         if (error)
5537                                 goto abort_change;
5538                 }
5539
5540                 tsec->sid = sid;
5541         } else {
5542                 error = -EINVAL;
5543                 goto abort_change;
5544         }
5545
5546         commit_creds(new);
5547         return size;
5548
5549 abort_change:
5550         abort_creds(new);
5551         return error;
5552 }
5553
5554 static int selinux_ismaclabel(const char *name)
5555 {
5556         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5557 }
5558
5559 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5560 {
5561         return security_sid_to_context(secid, secdata, seclen);
5562 }
5563
5564 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5565 {
5566         return security_context_to_sid(secdata, seclen, secid);
5567 }
5568
5569 static void selinux_release_secctx(char *secdata, u32 seclen)
5570 {
5571         kfree(secdata);
5572 }
5573
5574 /*
5575  *      called with inode->i_mutex locked
5576  */
5577 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5578 {
5579         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5580 }
5581
5582 /*
5583  *      called with inode->i_mutex locked
5584  */
5585 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5586 {
5587         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5588 }
5589
5590 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5591 {
5592         int len = 0;
5593         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5594                                                 ctx, true);
5595         if (len < 0)
5596                 return len;
5597         *ctxlen = len;
5598         return 0;
5599 }
5600 #ifdef CONFIG_KEYS
5601
5602 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5603                              unsigned long flags)
5604 {
5605         const struct task_security_struct *tsec;
5606         struct key_security_struct *ksec;
5607
5608         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5609         if (!ksec)
5610                 return -ENOMEM;
5611
5612         tsec = cred->security;
5613         if (tsec->keycreate_sid)
5614                 ksec->sid = tsec->keycreate_sid;
5615         else
5616                 ksec->sid = tsec->sid;
5617
5618         k->security = ksec;
5619         return 0;
5620 }
5621
5622 static void selinux_key_free(struct key *k)
5623 {
5624         struct key_security_struct *ksec = k->security;
5625
5626         k->security = NULL;
5627         kfree(ksec);
5628 }
5629
5630 static int selinux_key_permission(key_ref_t key_ref,
5631                                   const struct cred *cred,
5632                                   key_perm_t perm)
5633 {
5634         struct key *key;
5635         struct key_security_struct *ksec;
5636         u32 sid;
5637
5638         /* if no specific permissions are requested, we skip the
5639            permission check. No serious, additional covert channels
5640            appear to be created. */
5641         if (perm == 0)
5642                 return 0;
5643
5644         sid = cred_sid(cred);
5645
5646         key = key_ref_to_ptr(key_ref);
5647         ksec = key->security;
5648
5649         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5650 }
5651
5652 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5653 {
5654         struct key_security_struct *ksec = key->security;
5655         char *context = NULL;
5656         unsigned len;
5657         int rc;
5658
5659         rc = security_sid_to_context(ksec->sid, &context, &len);
5660         if (!rc)
5661                 rc = len;
5662         *_buffer = context;
5663         return rc;
5664 }
5665
5666 #endif
5667
5668 static struct security_operations selinux_ops = {
5669         .name =                         "selinux",
5670
5671         .ptrace_access_check =          selinux_ptrace_access_check,
5672         .ptrace_traceme =               selinux_ptrace_traceme,
5673         .capget =                       selinux_capget,
5674         .capset =                       selinux_capset,
5675         .capable =                      selinux_capable,
5676         .quotactl =                     selinux_quotactl,
5677         .quota_on =                     selinux_quota_on,
5678         .syslog =                       selinux_syslog,
5679         .vm_enough_memory =             selinux_vm_enough_memory,
5680
5681         .netlink_send =                 selinux_netlink_send,
5682
5683         .bprm_set_creds =               selinux_bprm_set_creds,
5684         .bprm_committing_creds =        selinux_bprm_committing_creds,
5685         .bprm_committed_creds =         selinux_bprm_committed_creds,
5686         .bprm_secureexec =              selinux_bprm_secureexec,
5687
5688         .sb_alloc_security =            selinux_sb_alloc_security,
5689         .sb_free_security =             selinux_sb_free_security,
5690         .sb_copy_data =                 selinux_sb_copy_data,
5691         .sb_remount =                   selinux_sb_remount,
5692         .sb_kern_mount =                selinux_sb_kern_mount,
5693         .sb_show_options =              selinux_sb_show_options,
5694         .sb_statfs =                    selinux_sb_statfs,
5695         .sb_mount =                     selinux_mount,
5696         .sb_umount =                    selinux_umount,
5697         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5698         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5699         .sb_parse_opts_str =            selinux_parse_opts_str,
5700
5701         .dentry_init_security =         selinux_dentry_init_security,
5702
5703         .inode_alloc_security =         selinux_inode_alloc_security,
5704         .inode_free_security =          selinux_inode_free_security,
5705         .inode_init_security =          selinux_inode_init_security,
5706         .inode_create =                 selinux_inode_create,
5707         .inode_link =                   selinux_inode_link,
5708         .inode_unlink =                 selinux_inode_unlink,
5709         .inode_symlink =                selinux_inode_symlink,
5710         .inode_mkdir =                  selinux_inode_mkdir,
5711         .inode_rmdir =                  selinux_inode_rmdir,
5712         .inode_mknod =                  selinux_inode_mknod,
5713         .inode_rename =                 selinux_inode_rename,
5714         .inode_readlink =               selinux_inode_readlink,
5715         .inode_follow_link =            selinux_inode_follow_link,
5716         .inode_permission =             selinux_inode_permission,
5717         .inode_setattr =                selinux_inode_setattr,
5718         .inode_getattr =                selinux_inode_getattr,
5719         .inode_setxattr =               selinux_inode_setxattr,
5720         .inode_post_setxattr =          selinux_inode_post_setxattr,
5721         .inode_getxattr =               selinux_inode_getxattr,
5722         .inode_listxattr =              selinux_inode_listxattr,
5723         .inode_removexattr =            selinux_inode_removexattr,
5724         .inode_getsecurity =            selinux_inode_getsecurity,
5725         .inode_setsecurity =            selinux_inode_setsecurity,
5726         .inode_listsecurity =           selinux_inode_listsecurity,
5727         .inode_getsecid =               selinux_inode_getsecid,
5728
5729         .file_permission =              selinux_file_permission,
5730         .file_alloc_security =          selinux_file_alloc_security,
5731         .file_free_security =           selinux_file_free_security,
5732         .file_ioctl =                   selinux_file_ioctl,
5733         .mmap_file =                    selinux_mmap_file,
5734         .mmap_addr =                    selinux_mmap_addr,
5735         .file_mprotect =                selinux_file_mprotect,
5736         .file_lock =                    selinux_file_lock,
5737         .file_fcntl =                   selinux_file_fcntl,
5738         .file_set_fowner =              selinux_file_set_fowner,
5739         .file_send_sigiotask =          selinux_file_send_sigiotask,
5740         .file_receive =                 selinux_file_receive,
5741
5742         .file_open =                    selinux_file_open,
5743
5744         .task_create =                  selinux_task_create,
5745         .cred_alloc_blank =             selinux_cred_alloc_blank,
5746         .cred_free =                    selinux_cred_free,
5747         .cred_prepare =                 selinux_cred_prepare,
5748         .cred_transfer =                selinux_cred_transfer,
5749         .kernel_act_as =                selinux_kernel_act_as,
5750         .kernel_create_files_as =       selinux_kernel_create_files_as,
5751         .kernel_module_request =        selinux_kernel_module_request,
5752         .task_setpgid =                 selinux_task_setpgid,
5753         .task_getpgid =                 selinux_task_getpgid,
5754         .task_getsid =                  selinux_task_getsid,
5755         .task_getsecid =                selinux_task_getsecid,
5756         .task_setnice =                 selinux_task_setnice,
5757         .task_setioprio =               selinux_task_setioprio,
5758         .task_getioprio =               selinux_task_getioprio,
5759         .task_setrlimit =               selinux_task_setrlimit,
5760         .task_setscheduler =            selinux_task_setscheduler,
5761         .task_getscheduler =            selinux_task_getscheduler,
5762         .task_movememory =              selinux_task_movememory,
5763         .task_kill =                    selinux_task_kill,
5764         .task_wait =                    selinux_task_wait,
5765         .task_to_inode =                selinux_task_to_inode,
5766
5767         .ipc_permission =               selinux_ipc_permission,
5768         .ipc_getsecid =                 selinux_ipc_getsecid,
5769
5770         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5771         .msg_msg_free_security =        selinux_msg_msg_free_security,
5772
5773         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5774         .msg_queue_free_security =      selinux_msg_queue_free_security,
5775         .msg_queue_associate =          selinux_msg_queue_associate,
5776         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5777         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5778         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5779
5780         .shm_alloc_security =           selinux_shm_alloc_security,
5781         .shm_free_security =            selinux_shm_free_security,
5782         .shm_associate =                selinux_shm_associate,
5783         .shm_shmctl =                   selinux_shm_shmctl,
5784         .shm_shmat =                    selinux_shm_shmat,
5785
5786         .sem_alloc_security =           selinux_sem_alloc_security,
5787         .sem_free_security =            selinux_sem_free_security,
5788         .sem_associate =                selinux_sem_associate,
5789         .sem_semctl =                   selinux_sem_semctl,
5790         .sem_semop =                    selinux_sem_semop,
5791
5792         .d_instantiate =                selinux_d_instantiate,
5793
5794         .getprocattr =                  selinux_getprocattr,
5795         .setprocattr =                  selinux_setprocattr,
5796
5797         .ismaclabel =                   selinux_ismaclabel,
5798         .secid_to_secctx =              selinux_secid_to_secctx,
5799         .secctx_to_secid =              selinux_secctx_to_secid,
5800         .release_secctx =               selinux_release_secctx,
5801         .inode_notifysecctx =           selinux_inode_notifysecctx,
5802         .inode_setsecctx =              selinux_inode_setsecctx,
5803         .inode_getsecctx =              selinux_inode_getsecctx,
5804
5805         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5806         .unix_may_send =                selinux_socket_unix_may_send,
5807
5808         .socket_create =                selinux_socket_create,
5809         .socket_post_create =           selinux_socket_post_create,
5810         .socket_bind =                  selinux_socket_bind,
5811         .socket_connect =               selinux_socket_connect,
5812         .socket_listen =                selinux_socket_listen,
5813         .socket_accept =                selinux_socket_accept,
5814         .socket_sendmsg =               selinux_socket_sendmsg,
5815         .socket_recvmsg =               selinux_socket_recvmsg,
5816         .socket_getsockname =           selinux_socket_getsockname,
5817         .socket_getpeername =           selinux_socket_getpeername,
5818         .socket_getsockopt =            selinux_socket_getsockopt,
5819         .socket_setsockopt =            selinux_socket_setsockopt,
5820         .socket_shutdown =              selinux_socket_shutdown,
5821         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5822         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5823         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5824         .sk_alloc_security =            selinux_sk_alloc_security,
5825         .sk_free_security =             selinux_sk_free_security,
5826         .sk_clone_security =            selinux_sk_clone_security,
5827         .sk_getsecid =                  selinux_sk_getsecid,
5828         .sock_graft =                   selinux_sock_graft,
5829         .inet_conn_request =            selinux_inet_conn_request,
5830         .inet_csk_clone =               selinux_inet_csk_clone,
5831         .inet_conn_established =        selinux_inet_conn_established,
5832         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5833         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5834         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5835         .req_classify_flow =            selinux_req_classify_flow,
5836         .tun_dev_alloc_security =       selinux_tun_dev_alloc_security,
5837         .tun_dev_free_security =        selinux_tun_dev_free_security,
5838         .tun_dev_create =               selinux_tun_dev_create,
5839         .tun_dev_attach_queue =         selinux_tun_dev_attach_queue,
5840         .tun_dev_attach =               selinux_tun_dev_attach,
5841         .tun_dev_open =                 selinux_tun_dev_open,
5842         .skb_owned_by =                 selinux_skb_owned_by,
5843
5844 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5845         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5846         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5847         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5848         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5849         .xfrm_state_alloc =             selinux_xfrm_state_alloc,
5850         .xfrm_state_alloc_acquire =     selinux_xfrm_state_alloc_acquire,
5851         .xfrm_state_free_security =     selinux_xfrm_state_free,
5852         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5853         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5854         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5855         .xfrm_decode_session =          selinux_xfrm_decode_session,
5856 #endif
5857
5858 #ifdef CONFIG_KEYS
5859         .key_alloc =                    selinux_key_alloc,
5860         .key_free =                     selinux_key_free,
5861         .key_permission =               selinux_key_permission,
5862         .key_getsecurity =              selinux_key_getsecurity,
5863 #endif
5864
5865 #ifdef CONFIG_AUDIT
5866         .audit_rule_init =              selinux_audit_rule_init,
5867         .audit_rule_known =             selinux_audit_rule_known,
5868         .audit_rule_match =             selinux_audit_rule_match,
5869         .audit_rule_free =              selinux_audit_rule_free,
5870 #endif
5871 };
5872
5873 static __init int selinux_init(void)
5874 {
5875         if (!security_module_enable(&selinux_ops)) {
5876                 selinux_enabled = 0;
5877                 return 0;
5878         }
5879
5880         if (!selinux_enabled) {
5881                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5882                 return 0;
5883         }
5884
5885         printk(KERN_INFO "SELinux:  Initializing.\n");
5886
5887         /* Set the security state for the initial task. */
5888         cred_init_security();
5889
5890         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5891
5892         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5893                                             sizeof(struct inode_security_struct),
5894                                             0, SLAB_PANIC, NULL);
5895         avc_init();
5896
5897         if (register_security(&selinux_ops))
5898                 panic("SELinux: Unable to register with kernel.\n");
5899
5900         if (selinux_enforcing)
5901                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5902         else
5903                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5904
5905         return 0;
5906 }
5907
5908 static void delayed_superblock_init(struct super_block *sb, void *unused)
5909 {
5910         superblock_doinit(sb, NULL);
5911 }
5912
5913 void selinux_complete_init(void)
5914 {
5915         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5916
5917         /* Set up any superblocks initialized prior to the policy load. */
5918         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5919         iterate_supers(delayed_superblock_init, NULL);
5920 }
5921
5922 /* SELinux requires early initialization in order to label
5923    all processes and objects when they are created. */
5924 security_initcall(selinux_init);
5925
5926 #if defined(CONFIG_NETFILTER)
5927
5928 static struct nf_hook_ops selinux_ipv4_ops[] = {
5929         {
5930                 .hook =         selinux_ipv4_postroute,
5931                 .owner =        THIS_MODULE,
5932                 .pf =           NFPROTO_IPV4,
5933                 .hooknum =      NF_INET_POST_ROUTING,
5934                 .priority =     NF_IP_PRI_SELINUX_LAST,
5935         },
5936         {
5937                 .hook =         selinux_ipv4_forward,
5938                 .owner =        THIS_MODULE,
5939                 .pf =           NFPROTO_IPV4,
5940                 .hooknum =      NF_INET_FORWARD,
5941                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5942         },
5943         {
5944                 .hook =         selinux_ipv4_output,
5945                 .owner =        THIS_MODULE,
5946                 .pf =           NFPROTO_IPV4,
5947                 .hooknum =      NF_INET_LOCAL_OUT,
5948                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5949         }
5950 };
5951
5952 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5953
5954 static struct nf_hook_ops selinux_ipv6_ops[] = {
5955         {
5956                 .hook =         selinux_ipv6_postroute,
5957                 .owner =        THIS_MODULE,
5958                 .pf =           NFPROTO_IPV6,
5959                 .hooknum =      NF_INET_POST_ROUTING,
5960                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5961         },
5962         {
5963                 .hook =         selinux_ipv6_forward,
5964                 .owner =        THIS_MODULE,
5965                 .pf =           NFPROTO_IPV6,
5966                 .hooknum =      NF_INET_FORWARD,
5967                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5968         }
5969 };
5970
5971 #endif  /* IPV6 */
5972
5973 static int __init selinux_nf_ip_init(void)
5974 {
5975         int err = 0;
5976
5977         if (!selinux_enabled)
5978                 goto out;
5979
5980         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5981
5982         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5983         if (err)
5984                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5985
5986 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5987         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5988         if (err)
5989                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5990 #endif  /* IPV6 */
5991
5992 out:
5993         return err;
5994 }
5995
5996 __initcall(selinux_nf_ip_init);
5997
5998 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5999 static void selinux_nf_ip_exit(void)
6000 {
6001         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
6002
6003         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6004 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6005         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6006 #endif  /* IPV6 */
6007 }
6008 #endif
6009
6010 #else /* CONFIG_NETFILTER */
6011
6012 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6013 #define selinux_nf_ip_exit()
6014 #endif
6015
6016 #endif /* CONFIG_NETFILTER */
6017
6018 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6019 static int selinux_disabled;
6020
6021 int selinux_disable(void)
6022 {
6023         if (ss_initialized) {
6024                 /* Not permitted after initial policy load. */
6025                 return -EINVAL;
6026         }
6027
6028         if (selinux_disabled) {
6029                 /* Only do this once. */
6030                 return -EINVAL;
6031         }
6032
6033         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
6034
6035         selinux_disabled = 1;
6036         selinux_enabled = 0;
6037
6038         reset_security_ops();
6039
6040         /* Try to destroy the avc node cache */
6041         avc_disable();
6042
6043         /* Unregister netfilter hooks. */
6044         selinux_nf_ip_exit();
6045
6046         /* Unregister selinuxfs. */
6047         exit_sel_fs();
6048
6049         return 0;
6050 }
6051 #endif