security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <[email protected]>
   7  *            Chris Vance, <[email protected]>
   8  *            Wayne Salamon, <[email protected]>
   9  *            James Morris <[email protected]>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <[email protected]>
  13  *                                         Eric Paris <[email protected]>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <[email protected]>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <[email protected]>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <[email protected]>
  20  *  Copyright (C) 2016 Mellanox Technologies
  21  *
  22  *      This program is free software; you can redistribute it and/or modify
  23  *      it under the terms of the GNU General Public License version 2,
  24  *      as published by the Free Software Foundation.
  25  */
  26
  27 #include <linux/init.h>
  28 #include <linux/kd.h>
  29 #include <linux/kernel.h>
  30 #include <linux/tracehook.h>
  31 #include <linux/errno.h>
  32 #include <linux/sched/signal.h>
  33 #include <linux/sched/task.h>
  34 #include <linux/lsm_hooks.h>
  35 #include <linux/xattr.h>
  36 #include <linux/capability.h>
  37 #include <linux/unistd.h>
  38 #include <linux/mm.h>
  39 #include <linux/mman.h>
  40 #include <linux/slab.h>
  41 #include <linux/pagemap.h>
  42 #include <linux/proc_fs.h>
  43 #include <linux/swap.h>
  44 #include <linux/spinlock.h>
  45 #include <linux/syscalls.h>
  46 #include <linux/dcache.h>
  47 #include <linux/file.h>
  48 #include <linux/fdtable.h>
  49 #include <linux/namei.h>
  50 #include <linux/mount.h>
  51 #include <linux/netfilter_ipv4.h>
  52 #include <linux/netfilter_ipv6.h>
  53 #include <linux/tty.h>
  54 #include <net/icmp.h>
  55 #include <net/ip.h>             /* for local_port_range[] */
  56 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  57 #include <net/inet_connection_sock.h>
  58 #include <net/net_namespace.h>
  59 #include <net/netlabel.h>
  60 #include <linux/uaccess.h>
  61 #include <asm/ioctls.h>
  62 #include <linux/atomic.h>
  63 #include <linux/bitops.h>
  64 #include <linux/interrupt.h>
  65 #include <linux/netdevice.h>    /* for network interface checks */
  66 #include <net/netlink.h>
  67 #include <linux/tcp.h>
  68 #include <linux/udp.h>
  69 #include <linux/dccp.h>
  70 #include <linux/sctp.h>
  71 #include <net/sctp/structs.h>
  72 #include <linux/quota.h>
  73 #include <linux/un.h>           /* for Unix socket types */
  74 #include <net/af_unix.h>        /* for Unix socket types */
  75 #include <linux/parser.h>
  76 #include <linux/nfs_mount.h>
  77 #include <net/ipv6.h>
  78 #include <linux/hugetlb.h>
  79 #include <linux/personality.h>
  80 #include <linux/audit.h>
  81 #include <linux/string.h>
  82 #include <linux/selinux.h>
  83 #include <linux/mutex.h>
  84 #include <linux/posix-timers.h>
  85 #include <linux/syslog.h>
  86 #include <linux/user_namespace.h>
  87 #include <linux/export.h>
  88 #include <linux/msg.h>
  89 #include <linux/shm.h>
  90 #include <linux/bpf.h>
  91
  92 #include "avc.h"
  93 #include "objsec.h"
  94 #include "netif.h"
  95 #include "netnode.h"
  96 #include "netport.h"
  97 #include "ibpkey.h"
  98 #include "xfrm.h"
  99 #include "netlabel.h"
 100 #include "audit.h"
 101 #include "avc_ss.h"
 102
 103 struct selinux_state selinux_state;
 104
 105 /* SECMARK reference count */
 106 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 107
 108 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 109 static int selinux_enforcing_boot;
 110
 111 static int __init enforcing_setup(char *str)
 112 {
 113         unsigned long enforcing;
 114         if (!kstrtoul(str, 0, &enforcing))
 115                 selinux_enforcing_boot = enforcing ? 1 : 0;
 116         return 1;
 117 }
 118 __setup("enforcing=", enforcing_setup);
 119 #else
 120 #define selinux_enforcing_boot 1
 121 #endif
 122
 123 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 124 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 125
 126 static int __init selinux_enabled_setup(char *str)
 127 {
 128         unsigned long enabled;
 129         if (!kstrtoul(str, 0, &enabled))
 130                 selinux_enabled = enabled ? 1 : 0;
 131         return 1;
 132 }
 133 __setup("selinux=", selinux_enabled_setup);
 134 #else
 135 int selinux_enabled = 1;
 136 #endif
 137
 138 static unsigned int selinux_checkreqprot_boot =
 139         CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
 140
 141 static int __init checkreqprot_setup(char *str)
 142 {
 143         unsigned long checkreqprot;
 144
 145         if (!kstrtoul(str, 0, &checkreqprot))
 146                 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
 147         return 1;
 148 }
 149 __setup("checkreqprot=", checkreqprot_setup);
 150
 151 static struct kmem_cache *sel_inode_cache;
 152 static struct kmem_cache *file_security_cache;
 153
 154 /**
 155  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 156  *
 157  * Description:
 158  * This function checks the SECMARK reference counter to see if any SECMARK
 159  * targets are currently configured, if the reference counter is greater than
 160  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 161  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 162  * policy capability is enabled, SECMARK is always considered enabled.
 163  *
 164  */
 165 static int selinux_secmark_enabled(void)
 166 {
 167         return (selinux_policycap_alwaysnetwork() ||
 168                 atomic_read(&selinux_secmark_refcount));
 169 }
 170
 171 /**
 172  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 173  *
 174  * Description:
 175  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 176  * (1) if any are enabled or false (0) if neither are enabled.  If the
 177  * always_check_network policy capability is enabled, peer labeling
 178  * is always considered enabled.
 179  *
 180  */
 181 static int selinux_peerlbl_enabled(void)
 182 {
 183         return (selinux_policycap_alwaysnetwork() ||
 184                 netlbl_enabled() || selinux_xfrm_enabled());
 185 }
 186
 187 static int selinux_netcache_avc_callback(u32 event)
 188 {
 189         if (event == AVC_CALLBACK_RESET) {
 190                 sel_netif_flush();
 191                 sel_netnode_flush();
 192                 sel_netport_flush();
 193                 synchronize_net();
 194         }
 195         return 0;
 196 }
 197
 198 static int selinux_lsm_notifier_avc_callback(u32 event)
 199 {
 200         if (event == AVC_CALLBACK_RESET) {
 201                 sel_ib_pkey_flush();
 202                 call_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 203         }
 204
 205         return 0;
 206 }
 207
 208 /*
 209  * initialise the security for the init task
 210  */
 211 static void cred_init_security(void)
 212 {
 213         struct cred *cred = (struct cred *) current->real_cred;
 214         struct task_security_struct *tsec;
 215
 216         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 217         if (!tsec)
 218                 panic("SELinux:  Failed to initialize initial task.\n");
 219
 220         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 221         cred->security = tsec;
 222 }
 223
 224 /*
 225  * get the security ID of a set of credentials
 226  */
 227 static inline u32 cred_sid(const struct cred *cred)
 228 {
 229         const struct task_security_struct *tsec;
 230
 231         tsec = cred->security;
 232         return tsec->sid;
 233 }
 234
 235 /*
 236  * get the objective security ID of a task
 237  */
 238 static inline u32 task_sid(const struct task_struct *task)
 239 {
 240         u32 sid;
 241
 242         rcu_read_lock();
 243         sid = cred_sid(__task_cred(task));
 244         rcu_read_unlock();
 245         return sid;
 246 }
 247
 248 /* Allocate and free functions for each kind of security blob. */
 249
 250 static int inode_alloc_security(struct inode *inode)
 251 {
 252         struct inode_security_struct *isec;
 253         u32 sid = current_sid();
 254
 255         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 256         if (!isec)
 257                 return -ENOMEM;
 258
 259         spin_lock_init(&isec->lock);
 260         INIT_LIST_HEAD(&isec->list);
 261         isec->inode = inode;
 262         isec->sid = SECINITSID_UNLABELED;
 263         isec->sclass = SECCLASS_FILE;
 264         isec->task_sid = sid;
 265         isec->initialized = LABEL_INVALID;
 266         inode->i_security = isec;
 267
 268         return 0;
 269 }
 270
 271 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 272
 273 /*
 274  * Try reloading inode security labels that have been marked as invalid.  The
 275  * @may_sleep parameter indicates when sleeping and thus reloading labels is
 276  * allowed; when set to false, returns -ECHILD when the label is
 277  * invalid.  The @dentry parameter should be set to a dentry of the inode.
 278  */
 279 static int __inode_security_revalidate(struct inode *inode,
 280                                        struct dentry *dentry,
 281                                        bool may_sleep)
 282 {
 283         struct inode_security_struct *isec = inode->i_security;
 284
 285         might_sleep_if(may_sleep);
 286
 287         if (selinux_state.initialized &&
 288             isec->initialized != LABEL_INITIALIZED) {
 289                 if (!may_sleep)
 290                         return -ECHILD;
 291
 292                 /*
 293                  * Try reloading the inode security label.  This will fail if
 294                  * @opt_dentry is NULL and no dentry for this inode can be
 295                  * found; in that case, continue using the old label.
 296                  */
 297                 inode_doinit_with_dentry(inode, dentry);
 298         }
 299         return 0;
 300 }
 301
 302 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 303 {
 304         return inode->i_security;
 305 }
 306
 307 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 308 {
 309         int error;
 310
 311         error = __inode_security_revalidate(inode, NULL, !rcu);
 312         if (error)
 313                 return ERR_PTR(error);
 314         return inode->i_security;
 315 }
 316
 317 /*
 318  * Get the security label of an inode.
 319  */
 320 static struct inode_security_struct *inode_security(struct inode *inode)
 321 {
 322         __inode_security_revalidate(inode, NULL, true);
 323         return inode->i_security;
 324 }
 325
 326 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 327 {
 328         struct inode *inode = d_backing_inode(dentry);
 329
 330         return inode->i_security;
 331 }
 332
 333 /*
 334  * Get the security label of a dentry's backing inode.
 335  */
 336 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 337 {
 338         struct inode *inode = d_backing_inode(dentry);
 339
 340         __inode_security_revalidate(inode, dentry, true);
 341         return inode->i_security;
 342 }
 343
 344 static void inode_free_rcu(struct rcu_head *head)
 345 {
 346         struct inode_security_struct *isec;
 347
 348         isec = container_of(head, struct inode_security_struct, rcu);
 349         kmem_cache_free(sel_inode_cache, isec);
 350 }
 351
 352 static void inode_free_security(struct inode *inode)
 353 {
 354         struct inode_security_struct *isec = inode->i_security;
 355         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 356
 357         /*
 358          * As not all inode security structures are in a list, we check for
 359          * empty list outside of the lock to make sure that we won't waste
 360          * time taking a lock doing nothing.
 361          *
 362          * The list_del_init() function can be safely called more than once.
 363          * It should not be possible for this function to be called with
 364          * concurrent list_add(), but for better safety against future changes
 365          * in the code, we use list_empty_careful() here.
 366          */
 367         if (!list_empty_careful(&isec->list)) {
 368                 spin_lock(&sbsec->isec_lock);
 369                 list_del_init(&isec->list);
 370                 spin_unlock(&sbsec->isec_lock);
 371         }
 372
 373         /*
 374          * The inode may still be referenced in a path walk and
 375          * a call to selinux_inode_permission() can be made
 376          * after inode_free_security() is called. Ideally, the VFS
 377          * wouldn't do this, but fixing that is a much harder
 378          * job. For now, simply free the i_security via RCU, and
 379          * leave the current inode->i_security pointer intact.
 380          * The inode will be freed after the RCU grace period too.
 381          */
 382         call_rcu(&isec->rcu, inode_free_rcu);
 383 }
 384
 385 static int file_alloc_security(struct file *file)
 386 {
 387         struct file_security_struct *fsec;
 388         u32 sid = current_sid();
 389
 390         fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
 391         if (!fsec)
 392                 return -ENOMEM;
 393
 394         fsec->sid = sid;
 395         fsec->fown_sid = sid;
 396         file->f_security = fsec;
 397
 398         return 0;
 399 }
 400
 401 static void file_free_security(struct file *file)
 402 {
 403         struct file_security_struct *fsec = file->f_security;
 404         file->f_security = NULL;
 405         kmem_cache_free(file_security_cache, fsec);
 406 }
 407
 408 static int superblock_alloc_security(struct super_block *sb)
 409 {
 410         struct superblock_security_struct *sbsec;
 411
 412         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 413         if (!sbsec)
 414                 return -ENOMEM;
 415
 416         mutex_init(&sbsec->lock);
 417         INIT_LIST_HEAD(&sbsec->isec_head);
 418         spin_lock_init(&sbsec->isec_lock);
 419         sbsec->sb = sb;
 420         sbsec->sid = SECINITSID_UNLABELED;
 421         sbsec->def_sid = SECINITSID_FILE;
 422         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 423         sb->s_security = sbsec;
 424
 425         return 0;
 426 }
 427
 428 static void superblock_free_security(struct super_block *sb)
 429 {
 430         struct superblock_security_struct *sbsec = sb->s_security;
 431         sb->s_security = NULL;
 432         kfree(sbsec);
 433 }
 434
 435 static inline int inode_doinit(struct inode *inode)
 436 {
 437         return inode_doinit_with_dentry(inode, NULL);
 438 }
 439
 440 enum {
 441         Opt_error = -1,
 442         Opt_context = 1,
 443         Opt_fscontext = 2,
 444         Opt_defcontext = 3,
 445         Opt_rootcontext = 4,
 446         Opt_labelsupport = 5,
 447         Opt_nextmntopt = 6,
 448 };
 449
 450 #define NUM_SEL_MNT_OPTS        (Opt_nextmntopt - 1)
 451
 452 static const match_table_t tokens = {
 453         {Opt_context, CONTEXT_STR "%s"},
 454         {Opt_fscontext, FSCONTEXT_STR "%s"},
 455         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 456         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 457         {Opt_labelsupport, LABELSUPP_STR},
 458         {Opt_error, NULL},
 459 };
 460
 461 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 462
 463 static int may_context_mount_sb_relabel(u32 sid,
 464                         struct superblock_security_struct *sbsec,
 465                         const struct cred *cred)
 466 {
 467         const struct task_security_struct *tsec = cred->security;
 468         int rc;
 469
 470         rc = avc_has_perm(&selinux_state,
 471                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 472                           FILESYSTEM__RELABELFROM, NULL);
 473         if (rc)
 474                 return rc;
 475
 476         rc = avc_has_perm(&selinux_state,
 477                           tsec->sid, sid, SECCLASS_FILESYSTEM,
 478                           FILESYSTEM__RELABELTO, NULL);
 479         return rc;
 480 }
 481
 482 static int may_context_mount_inode_relabel(u32 sid,
 483                         struct superblock_security_struct *sbsec,
 484                         const struct cred *cred)
 485 {
 486         const struct task_security_struct *tsec = cred->security;
 487         int rc;
 488         rc = avc_has_perm(&selinux_state,
 489                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 490                           FILESYSTEM__RELABELFROM, NULL);
 491         if (rc)
 492                 return rc;
 493
 494         rc = avc_has_perm(&selinux_state,
 495                           sid, sbsec->sid, SECCLASS_FILESYSTEM,
 496                           FILESYSTEM__ASSOCIATE, NULL);
 497         return rc;
 498 }
 499
 500 static int selinux_is_sblabel_mnt(struct super_block *sb)
 501 {
 502         struct superblock_security_struct *sbsec = sb->s_security;
 503
 504         return sbsec->behavior == SECURITY_FS_USE_XATTR ||
 505                 sbsec->behavior == SECURITY_FS_USE_TRANS ||
 506                 sbsec->behavior == SECURITY_FS_USE_TASK ||
 507                 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
 508                 /* Special handling. Genfs but also in-core setxattr handler */
 509                 !strcmp(sb->s_type->name, "sysfs") ||
 510                 !strcmp(sb->s_type->name, "pstore") ||
 511                 !strcmp(sb->s_type->name, "debugfs") ||
 512                 !strcmp(sb->s_type->name, "tracefs") ||
 513                 !strcmp(sb->s_type->name, "rootfs") ||
 514                 (selinux_policycap_cgroupseclabel() &&
 515                  (!strcmp(sb->s_type->name, "cgroup") ||
 516                   !strcmp(sb->s_type->name, "cgroup2")));
 517 }
 518
 519 static int sb_finish_set_opts(struct super_block *sb)
 520 {
 521         struct superblock_security_struct *sbsec = sb->s_security;
 522         struct dentry *root = sb->s_root;
 523         struct inode *root_inode = d_backing_inode(root);
 524         int rc = 0;
 525
 526         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 527                 /* Make sure that the xattr handler exists and that no
 528                    error other than -ENODATA is returned by getxattr on
 529                    the root directory.  -ENODATA is ok, as this may be
 530                    the first boot of the SELinux kernel before we have
 531                    assigned xattr values to the filesystem. */
 532                 if (!(root_inode->i_opflags & IOP_XATTR)) {
 533                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 534                                "xattr support\n", sb->s_id, sb->s_type->name);
 535                         rc = -EOPNOTSUPP;
 536                         goto out;
 537                 }
 538
 539                 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 540                 if (rc < 0 && rc != -ENODATA) {
 541                         if (rc == -EOPNOTSUPP)
 542                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 543                                        "%s) has no security xattr handler\n",
 544                                        sb->s_id, sb->s_type->name);
 545                         else
 546                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 547                                        "%s) getxattr errno %d\n", sb->s_id,
 548                                        sb->s_type->name, -rc);
 549                         goto out;
 550                 }
 551         }
 552
 553         sbsec->flags |= SE_SBINITIALIZED;
 554
 555         /*
 556          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 557          * leave the flag untouched because sb_clone_mnt_opts might be handing
 558          * us a superblock that needs the flag to be cleared.
 559          */
 560         if (selinux_is_sblabel_mnt(sb))
 561                 sbsec->flags |= SBLABEL_MNT;
 562         else
 563                 sbsec->flags &= ~SBLABEL_MNT;
 564
 565         /* Initialize the root inode. */
 566         rc = inode_doinit_with_dentry(root_inode, root);
 567
 568         /* Initialize any other inodes associated with the superblock, e.g.
 569            inodes created prior to initial policy load or inodes created
 570            during get_sb by a pseudo filesystem that directly
 571            populates itself. */
 572         spin_lock(&sbsec->isec_lock);
 573 next_inode:
 574         if (!list_empty(&sbsec->isec_head)) {
 575                 struct inode_security_struct *isec =
 576                                 list_entry(sbsec->isec_head.next,
 577                                            struct inode_security_struct, list);
 578                 struct inode *inode = isec->inode;
 579                 list_del_init(&isec->list);
 580                 spin_unlock(&sbsec->isec_lock);
 581                 inode = igrab(inode);
 582                 if (inode) {
 583                         if (!IS_PRIVATE(inode))
 584                                 inode_doinit(inode);
 585                         iput(inode);
 586                 }
 587                 spin_lock(&sbsec->isec_lock);
 588                 goto next_inode;
 589         }
 590         spin_unlock(&sbsec->isec_lock);
 591 out:
 592         return rc;
 593 }
 594
 595 /*
 596  * This function should allow an FS to ask what it's mount security
 597  * options were so it can use those later for submounts, displaying
 598  * mount options, or whatever.
 599  */
 600 static int selinux_get_mnt_opts(const struct super_block *sb,
 601                                 struct security_mnt_opts *opts)
 602 {
 603         int rc = 0, i;
 604         struct superblock_security_struct *sbsec = sb->s_security;
 605         char *context = NULL;
 606         u32 len;
 607         char tmp;
 608
 609         security_init_mnt_opts(opts);
 610
 611         if (!(sbsec->flags & SE_SBINITIALIZED))
 612                 return -EINVAL;
 613
 614         if (!selinux_state.initialized)
 615                 return -EINVAL;
 616
 617         /* make sure we always check enough bits to cover the mask */
 618         BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
 619
 620         tmp = sbsec->flags & SE_MNTMASK;
 621         /* count the number of mount options for this sb */
 622         for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
 623                 if (tmp & 0x01)
 624                         opts->num_mnt_opts++;
 625                 tmp >>= 1;
 626         }
 627         /* Check if the Label support flag is set */
 628         if (sbsec->flags & SBLABEL_MNT)
 629                 opts->num_mnt_opts++;
 630
 631         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 632         if (!opts->mnt_opts) {
 633                 rc = -ENOMEM;
 634                 goto out_free;
 635         }
 636
 637         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 638         if (!opts->mnt_opts_flags) {
 639                 rc = -ENOMEM;
 640                 goto out_free;
 641         }
 642
 643         i = 0;
 644         if (sbsec->flags & FSCONTEXT_MNT) {
 645                 rc = security_sid_to_context(&selinux_state, sbsec->sid,
 646                                              &context, &len);
 647                 if (rc)
 648                         goto out_free;
 649                 opts->mnt_opts[i] = context;
 650                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 651         }
 652         if (sbsec->flags & CONTEXT_MNT) {
 653                 rc = security_sid_to_context(&selinux_state,
 654                                              sbsec->mntpoint_sid,
 655                                              &context, &len);
 656                 if (rc)
 657                         goto out_free;
 658                 opts->mnt_opts[i] = context;
 659                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 660         }
 661         if (sbsec->flags & DEFCONTEXT_MNT) {
 662                 rc = security_sid_to_context(&selinux_state, sbsec->def_sid,
 663                                              &context, &len);
 664                 if (rc)
 665                         goto out_free;
 666                 opts->mnt_opts[i] = context;
 667                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 668         }
 669         if (sbsec->flags & ROOTCONTEXT_MNT) {
 670                 struct dentry *root = sbsec->sb->s_root;
 671                 struct inode_security_struct *isec = backing_inode_security(root);
 672
 673                 rc = security_sid_to_context(&selinux_state, isec->sid,
 674                                              &context, &len);
 675                 if (rc)
 676                         goto out_free;
 677                 opts->mnt_opts[i] = context;
 678                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 679         }
 680         if (sbsec->flags & SBLABEL_MNT) {
 681                 opts->mnt_opts[i] = NULL;
 682                 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
 683         }
 684
 685         BUG_ON(i != opts->num_mnt_opts);
 686
 687         return 0;
 688
 689 out_free:
 690         security_free_mnt_opts(opts);
 691         return rc;
 692 }
 693
 694 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 695                       u32 old_sid, u32 new_sid)
 696 {
 697         char mnt_flags = sbsec->flags & SE_MNTMASK;
 698
 699         /* check if the old mount command had the same options */
 700         if (sbsec->flags & SE_SBINITIALIZED)
 701                 if (!(sbsec->flags & flag) ||
 702                     (old_sid != new_sid))
 703                         return 1;
 704
 705         /* check if we were passed the same options twice,
 706          * aka someone passed context=a,context=b
 707          */
 708         if (!(sbsec->flags & SE_SBINITIALIZED))
 709                 if (mnt_flags & flag)
 710                         return 1;
 711         return 0;
 712 }
 713
 714 /*
 715  * Allow filesystems with binary mount data to explicitly set mount point
 716  * labeling information.
 717  */
 718 static int selinux_set_mnt_opts(struct super_block *sb,
 719                                 struct security_mnt_opts *opts,
 720                                 unsigned long kern_flags,
 721                                 unsigned long *set_kern_flags)
 722 {
 723         const struct cred *cred = current_cred();
 724         int rc = 0, i;
 725         struct superblock_security_struct *sbsec = sb->s_security;
 726         const char *name = sb->s_type->name;
 727         struct dentry *root = sbsec->sb->s_root;
 728         struct inode_security_struct *root_isec;
 729         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 730         u32 defcontext_sid = 0;
 731         char **mount_options = opts->mnt_opts;
 732         int *flags = opts->mnt_opts_flags;
 733         int num_opts = opts->num_mnt_opts;
 734
 735         mutex_lock(&sbsec->lock);
 736
 737         if (!selinux_state.initialized) {
 738                 if (!num_opts) {
 739                         /* Defer initialization until selinux_complete_init,
 740                            after the initial policy is loaded and the security
 741                            server is ready to handle calls. */
 742                         goto out;
 743                 }
 744                 rc = -EINVAL;
 745                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 746                         "before the security server is initialized\n");
 747                 goto out;
 748         }
 749         if (kern_flags && !set_kern_flags) {
 750                 /* Specifying internal flags without providing a place to
 751                  * place the results is not allowed */
 752                 rc = -EINVAL;
 753                 goto out;
 754         }
 755
 756         /*
 757          * Binary mount data FS will come through this function twice.  Once
 758          * from an explicit call and once from the generic calls from the vfs.
 759          * Since the generic VFS calls will not contain any security mount data
 760          * we need to skip the double mount verification.
 761          *
 762          * This does open a hole in which we will not notice if the first
 763          * mount using this sb set explict options and a second mount using
 764          * this sb does not set any security options.  (The first options
 765          * will be used for both mounts)
 766          */
 767         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 768             && (num_opts == 0))
 769                 goto out;
 770
 771         root_isec = backing_inode_security_novalidate(root);
 772
 773         /*
 774          * parse the mount options, check if they are valid sids.
 775          * also check if someone is trying to mount the same sb more
 776          * than once with different security options.
 777          */
 778         for (i = 0; i < num_opts; i++) {
 779                 u32 sid;
 780
 781                 if (flags[i] == SBLABEL_MNT)
 782                         continue;
 783                 rc = security_context_str_to_sid(&selinux_state,
 784                                                  mount_options[i], &sid,
 785                                                  GFP_KERNEL);
 786                 if (rc) {
 787                         printk(KERN_WARNING "SELinux: security_context_str_to_sid"
 788                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 789                                mount_options[i], sb->s_id, name, rc);
 790                         goto out;
 791                 }
 792                 switch (flags[i]) {
 793                 case FSCONTEXT_MNT:
 794                         fscontext_sid = sid;
 795
 796                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 797                                         fscontext_sid))
 798                                 goto out_double_mount;
 799
 800                         sbsec->flags |= FSCONTEXT_MNT;
 801                         break;
 802                 case CONTEXT_MNT:
 803                         context_sid = sid;
 804
 805                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 806                                         context_sid))
 807                                 goto out_double_mount;
 808
 809                         sbsec->flags |= CONTEXT_MNT;
 810                         break;
 811                 case ROOTCONTEXT_MNT:
 812                         rootcontext_sid = sid;
 813
 814                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 815                                         rootcontext_sid))
 816                                 goto out_double_mount;
 817
 818                         sbsec->flags |= ROOTCONTEXT_MNT;
 819
 820                         break;
 821                 case DEFCONTEXT_MNT:
 822                         defcontext_sid = sid;
 823
 824                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 825                                         defcontext_sid))
 826                                 goto out_double_mount;
 827
 828                         sbsec->flags |= DEFCONTEXT_MNT;
 829
 830                         break;
 831                 default:
 832                         rc = -EINVAL;
 833                         goto out;
 834                 }
 835         }
 836
 837         if (sbsec->flags & SE_SBINITIALIZED) {
 838                 /* previously mounted with options, but not on this attempt? */
 839                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 840                         goto out_double_mount;
 841                 rc = 0;
 842                 goto out;
 843         }
 844
 845         if (strcmp(sb->s_type->name, "proc") == 0)
 846                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 847
 848         if (!strcmp(sb->s_type->name, "debugfs") ||
 849             !strcmp(sb->s_type->name, "tracefs") ||
 850             !strcmp(sb->s_type->name, "sysfs") ||
 851             !strcmp(sb->s_type->name, "pstore") ||
 852             !strcmp(sb->s_type->name, "cgroup") ||
 853             !strcmp(sb->s_type->name, "cgroup2"))
 854                 sbsec->flags |= SE_SBGENFS;
 855
 856         if (!sbsec->behavior) {
 857                 /*
 858                  * Determine the labeling behavior to use for this
 859                  * filesystem type.
 860                  */
 861                 rc = security_fs_use(&selinux_state, sb);
 862                 if (rc) {
 863                         printk(KERN_WARNING
 864                                 "%s: security_fs_use(%s) returned %d\n",
 865                                         __func__, sb->s_type->name, rc);
 866                         goto out;
 867                 }
 868         }
 869
 870         /*
 871          * If this is a user namespace mount and the filesystem type is not
 872          * explicitly whitelisted, then no contexts are allowed on the command
 873          * line and security labels must be ignored.
 874          */
 875         if (sb->s_user_ns != &init_user_ns &&
 876             strcmp(sb->s_type->name, "tmpfs") &&
 877             strcmp(sb->s_type->name, "ramfs") &&
 878             strcmp(sb->s_type->name, "devpts")) {
 879                 if (context_sid || fscontext_sid || rootcontext_sid ||
 880                     defcontext_sid) {
 881                         rc = -EACCES;
 882                         goto out;
 883                 }
 884                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 885                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 886                         rc = security_transition_sid(&selinux_state,
 887                                                      current_sid(),
 888                                                      current_sid(),
 889                                                      SECCLASS_FILE, NULL,
 890                                                      &sbsec->mntpoint_sid);
 891                         if (rc)
 892                                 goto out;
 893                 }
 894                 goto out_set_opts;
 895         }
 896
 897         /* sets the context of the superblock for the fs being mounted. */
 898         if (fscontext_sid) {
 899                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 900                 if (rc)
 901                         goto out;
 902
 903                 sbsec->sid = fscontext_sid;
 904         }
 905
 906         /*
 907          * Switch to using mount point labeling behavior.
 908          * sets the label used on all file below the mountpoint, and will set
 909          * the superblock context if not already set.
 910          */
 911         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 912                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 913                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 914         }
 915
 916         if (context_sid) {
 917                 if (!fscontext_sid) {
 918                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 919                                                           cred);
 920                         if (rc)
 921                                 goto out;
 922                         sbsec->sid = context_sid;
 923                 } else {
 924                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 925                                                              cred);
 926                         if (rc)
 927                                 goto out;
 928                 }
 929                 if (!rootcontext_sid)
 930                         rootcontext_sid = context_sid;
 931
 932                 sbsec->mntpoint_sid = context_sid;
 933                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 934         }
 935
 936         if (rootcontext_sid) {
 937                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 938                                                      cred);
 939                 if (rc)
 940                         goto out;
 941
 942                 root_isec->sid = rootcontext_sid;
 943                 root_isec->initialized = LABEL_INITIALIZED;
 944         }
 945
 946         if (defcontext_sid) {
 947                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 948                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 949                         rc = -EINVAL;
 950                         printk(KERN_WARNING "SELinux: defcontext option is "
 951                                "invalid for this filesystem type\n");
 952                         goto out;
 953                 }
 954
 955                 if (defcontext_sid != sbsec->def_sid) {
 956                         rc = may_context_mount_inode_relabel(defcontext_sid,
 957                                                              sbsec, cred);
 958                         if (rc)
 959                                 goto out;
 960                 }
 961
 962                 sbsec->def_sid = defcontext_sid;
 963         }
 964
 965 out_set_opts:
 966         rc = sb_finish_set_opts(sb);
 967 out:
 968         mutex_unlock(&sbsec->lock);
 969         return rc;
 970 out_double_mount:
 971         rc = -EINVAL;
 972         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 973                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 974         goto out;
 975 }
 976
 977 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 978                                     const struct super_block *newsb)
 979 {
 980         struct superblock_security_struct *old = oldsb->s_security;
 981         struct superblock_security_struct *new = newsb->s_security;
 982         char oldflags = old->flags & SE_MNTMASK;
 983         char newflags = new->flags & SE_MNTMASK;
 984
 985         if (oldflags != newflags)
 986                 goto mismatch;
 987         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 988                 goto mismatch;
 989         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 990                 goto mismatch;
 991         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 992                 goto mismatch;
 993         if (oldflags & ROOTCONTEXT_MNT) {
 994                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 995                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 996                 if (oldroot->sid != newroot->sid)
 997                         goto mismatch;
 998         }
 999         return 0;
1000 mismatch:
1001         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
1002                             "different security settings for (dev %s, "
1003                             "type %s)\n", newsb->s_id, newsb->s_type->name);
1004         return -EBUSY;
1005 }
1006
1007 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
1008                                         struct super_block *newsb,
1009                                         unsigned long kern_flags,
1010                                         unsigned long *set_kern_flags)
1011 {
1012         int rc = 0;
1013         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
1014         struct superblock_security_struct *newsbsec = newsb->s_security;
1015
1016         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
1017         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
1018         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
1019
1020         /*
1021          * if the parent was able to be mounted it clearly had no special lsm
1022          * mount options.  thus we can safely deal with this superblock later
1023          */
1024         if (!selinux_state.initialized)
1025                 return 0;
1026
1027         /*
1028          * Specifying internal flags without providing a place to
1029          * place the results is not allowed.
1030          */
1031         if (kern_flags && !set_kern_flags)
1032                 return -EINVAL;
1033
1034         /* how can we clone if the old one wasn't set up?? */
1035         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
1036
1037         /* if fs is reusing a sb, make sure that the contexts match */
1038         if (newsbsec->flags & SE_SBINITIALIZED)
1039                 return selinux_cmp_sb_context(oldsb, newsb);
1040
1041         mutex_lock(&newsbsec->lock);
1042
1043         newsbsec->flags = oldsbsec->flags;
1044
1045         newsbsec->sid = oldsbsec->sid;
1046         newsbsec->def_sid = oldsbsec->def_sid;
1047         newsbsec->behavior = oldsbsec->behavior;
1048
1049         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
1050                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
1051                 rc = security_fs_use(&selinux_state, newsb);
1052                 if (rc)
1053                         goto out;
1054         }
1055
1056         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
1057                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
1058                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
1059         }
1060
1061         if (set_context) {
1062                 u32 sid = oldsbsec->mntpoint_sid;
1063
1064                 if (!set_fscontext)
1065                         newsbsec->sid = sid;
1066                 if (!set_rootcontext) {
1067                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1068                         newisec->sid = sid;
1069                 }
1070                 newsbsec->mntpoint_sid = sid;
1071         }
1072         if (set_rootcontext) {
1073                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
1074                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1075
1076                 newisec->sid = oldisec->sid;
1077         }
1078
1079         sb_finish_set_opts(newsb);
1080 out:
1081         mutex_unlock(&newsbsec->lock);
1082         return rc;
1083 }
1084
1085 static int selinux_parse_opts_str(char *options,
1086                                   struct security_mnt_opts *opts)
1087 {
1088         char *p;
1089         char *context = NULL, *defcontext = NULL;
1090         char *fscontext = NULL, *rootcontext = NULL;
1091         int rc, num_mnt_opts = 0;
1092
1093         opts->num_mnt_opts = 0;
1094
1095         /* Standard string-based options. */
1096         while ((p = strsep(&options, "|")) != NULL) {
1097                 int token;
1098                 substring_t args[MAX_OPT_ARGS];
1099
1100                 if (!*p)
1101                         continue;
1102
1103                 token = match_token(p, tokens, args);
1104
1105                 switch (token) {
1106                 case Opt_context:
1107                         if (context || defcontext) {
1108                                 rc = -EINVAL;
1109                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1110                                 goto out_err;
1111                         }
1112                         context = match_strdup(&args[0]);
1113                         if (!context) {
1114                                 rc = -ENOMEM;
1115                                 goto out_err;
1116                         }
1117                         break;
1118
1119                 case Opt_fscontext:
1120                         if (fscontext) {
1121                                 rc = -EINVAL;
1122                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1123                                 goto out_err;
1124                         }
1125                         fscontext = match_strdup(&args[0]);
1126                         if (!fscontext) {
1127                                 rc = -ENOMEM;
1128                                 goto out_err;
1129                         }
1130                         break;
1131
1132                 case Opt_rootcontext:
1133                         if (rootcontext) {
1134                                 rc = -EINVAL;
1135                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1136                                 goto out_err;
1137                         }
1138                         rootcontext = match_strdup(&args[0]);
1139                         if (!rootcontext) {
1140                                 rc = -ENOMEM;
1141                                 goto out_err;
1142                         }
1143                         break;
1144
1145                 case Opt_defcontext:
1146                         if (context || defcontext) {
1147                                 rc = -EINVAL;
1148                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1149                                 goto out_err;
1150                         }
1151                         defcontext = match_strdup(&args[0]);
1152                         if (!defcontext) {
1153                                 rc = -ENOMEM;
1154                                 goto out_err;
1155                         }
1156                         break;
1157                 case Opt_labelsupport:
1158                         break;
1159                 default:
1160                         rc = -EINVAL;
1161                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
1162                         goto out_err;
1163
1164                 }
1165         }
1166
1167         rc = -ENOMEM;
1168         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1169         if (!opts->mnt_opts)
1170                 goto out_err;
1171
1172         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
1173                                        GFP_KERNEL);
1174         if (!opts->mnt_opts_flags)
1175                 goto out_err;
1176
1177         if (fscontext) {
1178                 opts->mnt_opts[num_mnt_opts] = fscontext;
1179                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1180         }
1181         if (context) {
1182                 opts->mnt_opts[num_mnt_opts] = context;
1183                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1184         }
1185         if (rootcontext) {
1186                 opts->mnt_opts[num_mnt_opts] = rootcontext;
1187                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1188         }
1189         if (defcontext) {
1190                 opts->mnt_opts[num_mnt_opts] = defcontext;
1191                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1192         }
1193
1194         opts->num_mnt_opts = num_mnt_opts;
1195         return 0;
1196
1197 out_err:
1198         security_free_mnt_opts(opts);
1199         kfree(context);
1200         kfree(defcontext);
1201         kfree(fscontext);
1202         kfree(rootcontext);
1203         return rc;
1204 }
1205 /*
1206  * string mount options parsing and call set the sbsec
1207  */
1208 static int superblock_doinit(struct super_block *sb, void *data)
1209 {
1210         int rc = 0;
1211         char *options = data;
1212         struct security_mnt_opts opts;
1213
1214         security_init_mnt_opts(&opts);
1215
1216         if (!data)
1217                 goto out;
1218
1219         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1220
1221         rc = selinux_parse_opts_str(options, &opts);
1222         if (rc)
1223                 goto out_err;
1224
1225 out:
1226         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1227
1228 out_err:
1229         security_free_mnt_opts(&opts);
1230         return rc;
1231 }
1232
1233 static void selinux_write_opts(struct seq_file *m,
1234                                struct security_mnt_opts *opts)
1235 {
1236         int i;
1237         char *prefix;
1238
1239         for (i = 0; i < opts->num_mnt_opts; i++) {
1240                 char *has_comma;
1241
1242                 if (opts->mnt_opts[i])
1243                         has_comma = strchr(opts->mnt_opts[i], ',');
1244                 else
1245                         has_comma = NULL;
1246
1247                 switch (opts->mnt_opts_flags[i]) {
1248                 case CONTEXT_MNT:
1249                         prefix = CONTEXT_STR;
1250                         break;
1251                 case FSCONTEXT_MNT:
1252                         prefix = FSCONTEXT_STR;
1253                         break;
1254                 case ROOTCONTEXT_MNT:
1255                         prefix = ROOTCONTEXT_STR;
1256                         break;
1257                 case DEFCONTEXT_MNT:
1258                         prefix = DEFCONTEXT_STR;
1259                         break;
1260                 case SBLABEL_MNT:
1261                         seq_putc(m, ',');
1262                         seq_puts(m, LABELSUPP_STR);
1263                         continue;
1264                 default:
1265                         BUG();
1266                         return;
1267                 };
1268                 /* we need a comma before each option */
1269                 seq_putc(m, ',');
1270                 seq_puts(m, prefix);
1271                 if (has_comma)
1272                         seq_putc(m, '\"');
1273                 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1274                 if (has_comma)
1275                         seq_putc(m, '\"');
1276         }
1277 }
1278
1279 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1280 {
1281         struct security_mnt_opts opts;
1282         int rc;
1283
1284         rc = selinux_get_mnt_opts(sb, &opts);
1285         if (rc) {
1286                 /* before policy load we may get EINVAL, don't show anything */
1287                 if (rc == -EINVAL)
1288                         rc = 0;
1289                 return rc;
1290         }
1291
1292         selinux_write_opts(m, &opts);
1293
1294         security_free_mnt_opts(&opts);
1295
1296         return rc;
1297 }
1298
1299 static inline u16 inode_mode_to_security_class(umode_t mode)
1300 {
1301         switch (mode & S_IFMT) {
1302         case S_IFSOCK:
1303                 return SECCLASS_SOCK_FILE;
1304         case S_IFLNK:
1305                 return SECCLASS_LNK_FILE;
1306         case S_IFREG:
1307                 return SECCLASS_FILE;
1308         case S_IFBLK:
1309                 return SECCLASS_BLK_FILE;
1310         case S_IFDIR:
1311                 return SECCLASS_DIR;
1312         case S_IFCHR:
1313                 return SECCLASS_CHR_FILE;
1314         case S_IFIFO:
1315                 return SECCLASS_FIFO_FILE;
1316
1317         }
1318
1319         return SECCLASS_FILE;
1320 }
1321
1322 static inline int default_protocol_stream(int protocol)
1323 {
1324         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1325 }
1326
1327 static inline int default_protocol_dgram(int protocol)
1328 {
1329         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1330 }
1331
1332 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1333 {
1334         int extsockclass = selinux_policycap_extsockclass();
1335
1336         switch (family) {
1337         case PF_UNIX:
1338                 switch (type) {
1339                 case SOCK_STREAM:
1340                 case SOCK_SEQPACKET:
1341                         return SECCLASS_UNIX_STREAM_SOCKET;
1342                 case SOCK_DGRAM:
1343                 case SOCK_RAW:
1344                         return SECCLASS_UNIX_DGRAM_SOCKET;
1345                 }
1346                 break;
1347         case PF_INET:
1348         case PF_INET6:
1349                 switch (type) {
1350                 case SOCK_STREAM:
1351                 case SOCK_SEQPACKET:
1352                         if (default_protocol_stream(protocol))
1353                                 return SECCLASS_TCP_SOCKET;
1354                         else if (extsockclass && protocol == IPPROTO_SCTP)
1355                                 return SECCLASS_SCTP_SOCKET;
1356                         else
1357                                 return SECCLASS_RAWIP_SOCKET;
1358                 case SOCK_DGRAM:
1359                         if (default_protocol_dgram(protocol))
1360                                 return SECCLASS_UDP_SOCKET;
1361                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1362                                                   protocol == IPPROTO_ICMPV6))
1363                                 return SECCLASS_ICMP_SOCKET;
1364                         else
1365                                 return SECCLASS_RAWIP_SOCKET;
1366                 case SOCK_DCCP:
1367                         return SECCLASS_DCCP_SOCKET;
1368                 default:
1369                         return SECCLASS_RAWIP_SOCKET;
1370                 }
1371                 break;
1372         case PF_NETLINK:
1373                 switch (protocol) {
1374                 case NETLINK_ROUTE:
1375                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1376                 case NETLINK_SOCK_DIAG:
1377                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1378                 case NETLINK_NFLOG:
1379                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1380                 case NETLINK_XFRM:
1381                         return SECCLASS_NETLINK_XFRM_SOCKET;
1382                 case NETLINK_SELINUX:
1383                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1384                 case NETLINK_ISCSI:
1385                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1386                 case NETLINK_AUDIT:
1387                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1388                 case NETLINK_FIB_LOOKUP:
1389                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1390                 case NETLINK_CONNECTOR:
1391                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1392                 case NETLINK_NETFILTER:
1393                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1394                 case NETLINK_DNRTMSG:
1395                         return SECCLASS_NETLINK_DNRT_SOCKET;
1396                 case NETLINK_KOBJECT_UEVENT:
1397                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1398                 case NETLINK_GENERIC:
1399                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1400                 case NETLINK_SCSITRANSPORT:
1401                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1402                 case NETLINK_RDMA:
1403                         return SECCLASS_NETLINK_RDMA_SOCKET;
1404                 case NETLINK_CRYPTO:
1405                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1406                 default:
1407                         return SECCLASS_NETLINK_SOCKET;
1408                 }
1409         case PF_PACKET:
1410                 return SECCLASS_PACKET_SOCKET;
1411         case PF_KEY:
1412                 return SECCLASS_KEY_SOCKET;
1413         case PF_APPLETALK:
1414                 return SECCLASS_APPLETALK_SOCKET;
1415         }
1416
1417         if (extsockclass) {
1418                 switch (family) {
1419                 case PF_AX25:
1420                         return SECCLASS_AX25_SOCKET;
1421                 case PF_IPX:
1422                         return SECCLASS_IPX_SOCKET;
1423                 case PF_NETROM:
1424                         return SECCLASS_NETROM_SOCKET;
1425                 case PF_ATMPVC:
1426                         return SECCLASS_ATMPVC_SOCKET;
1427                 case PF_X25:
1428                         return SECCLASS_X25_SOCKET;
1429                 case PF_ROSE:
1430                         return SECCLASS_ROSE_SOCKET;
1431                 case PF_DECnet:
1432                         return SECCLASS_DECNET_SOCKET;
1433                 case PF_ATMSVC:
1434                         return SECCLASS_ATMSVC_SOCKET;
1435                 case PF_RDS:
1436                         return SECCLASS_RDS_SOCKET;
1437                 case PF_IRDA:
1438                         return SECCLASS_IRDA_SOCKET;
1439                 case PF_PPPOX:
1440                         return SECCLASS_PPPOX_SOCKET;
1441                 case PF_LLC:
1442                         return SECCLASS_LLC_SOCKET;
1443                 case PF_CAN:
1444                         return SECCLASS_CAN_SOCKET;
1445                 case PF_TIPC:
1446                         return SECCLASS_TIPC_SOCKET;
1447                 case PF_BLUETOOTH:
1448                         return SECCLASS_BLUETOOTH_SOCKET;
1449                 case PF_IUCV:
1450                         return SECCLASS_IUCV_SOCKET;
1451                 case PF_RXRPC:
1452                         return SECCLASS_RXRPC_SOCKET;
1453                 case PF_ISDN:
1454                         return SECCLASS_ISDN_SOCKET;
1455                 case PF_PHONET:
1456                         return SECCLASS_PHONET_SOCKET;
1457                 case PF_IEEE802154:
1458                         return SECCLASS_IEEE802154_SOCKET;
1459                 case PF_CAIF:
1460                         return SECCLASS_CAIF_SOCKET;
1461                 case PF_ALG:
1462                         return SECCLASS_ALG_SOCKET;
1463                 case PF_NFC:
1464                         return SECCLASS_NFC_SOCKET;
1465                 case PF_VSOCK:
1466                         return SECCLASS_VSOCK_SOCKET;
1467                 case PF_KCM:
1468                         return SECCLASS_KCM_SOCKET;
1469                 case PF_QIPCRTR:
1470                         return SECCLASS_QIPCRTR_SOCKET;
1471                 case PF_SMC:
1472                         return SECCLASS_SMC_SOCKET;
1473                 case PF_XDP:
1474                         return SECCLASS_XDP_SOCKET;
1475 #if PF_MAX > 45
1476 #error New address family defined, please update this function.
1477 #endif
1478                 }
1479         }
1480
1481         return SECCLASS_SOCKET;
1482 }
1483
1484 static int selinux_genfs_get_sid(struct dentry *dentry,
1485                                  u16 tclass,
1486                                  u16 flags,
1487                                  u32 *sid)
1488 {
1489         int rc;
1490         struct super_block *sb = dentry->d_sb;
1491         char *buffer, *path;
1492
1493         buffer = (char *)__get_free_page(GFP_KERNEL);
1494         if (!buffer)
1495                 return -ENOMEM;
1496
1497         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1498         if (IS_ERR(path))
1499                 rc = PTR_ERR(path);
1500         else {
1501                 if (flags & SE_SBPROC) {
1502                         /* each process gets a /proc/PID/ entry. Strip off the
1503                          * PID part to get a valid selinux labeling.
1504                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1505                         while (path[1] >= '0' && path[1] <= '9') {
1506                                 path[1] = '/';
1507                                 path++;
1508                         }
1509                 }
1510                 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1511                                         path, tclass, sid);
1512         }
1513         free_page((unsigned long)buffer);
1514         return rc;
1515 }
1516
1517 /* The inode's security attributes must be initialized before first use. */
1518 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1519 {
1520         struct superblock_security_struct *sbsec = NULL;
1521         struct inode_security_struct *isec = inode->i_security;
1522         u32 task_sid, sid = 0;
1523         u16 sclass;
1524         struct dentry *dentry;
1525 #define INITCONTEXTLEN 255
1526         char *context = NULL;
1527         unsigned len = 0;
1528         int rc = 0;
1529
1530         if (isec->initialized == LABEL_INITIALIZED)
1531                 return 0;
1532
1533         spin_lock(&isec->lock);
1534         if (isec->initialized == LABEL_INITIALIZED)
1535                 goto out_unlock;
1536
1537         if (isec->sclass == SECCLASS_FILE)
1538                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1539
1540         sbsec = inode->i_sb->s_security;
1541         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1542                 /* Defer initialization until selinux_complete_init,
1543                    after the initial policy is loaded and the security
1544                    server is ready to handle calls. */
1545                 spin_lock(&sbsec->isec_lock);
1546                 if (list_empty(&isec->list))
1547                         list_add(&isec->list, &sbsec->isec_head);
1548                 spin_unlock(&sbsec->isec_lock);
1549                 goto out_unlock;
1550         }
1551
1552         sclass = isec->sclass;
1553         task_sid = isec->task_sid;
1554         sid = isec->sid;
1555         isec->initialized = LABEL_PENDING;
1556         spin_unlock(&isec->lock);
1557
1558         switch (sbsec->behavior) {
1559         case SECURITY_FS_USE_NATIVE:
1560                 break;
1561         case SECURITY_FS_USE_XATTR:
1562                 if (!(inode->i_opflags & IOP_XATTR)) {
1563                         sid = sbsec->def_sid;
1564                         break;
1565                 }
1566                 /* Need a dentry, since the xattr API requires one.
1567                    Life would be simpler if we could just pass the inode. */
1568                 if (opt_dentry) {
1569                         /* Called from d_instantiate or d_splice_alias. */
1570                         dentry = dget(opt_dentry);
1571                 } else {
1572                         /*
1573                          * Called from selinux_complete_init, try to find a dentry.
1574                          * Some filesystems really want a connected one, so try
1575                          * that first.  We could split SECURITY_FS_USE_XATTR in
1576                          * two, depending upon that...
1577                          */
1578                         dentry = d_find_alias(inode);
1579                         if (!dentry)
1580                                 dentry = d_find_any_alias(inode);
1581                 }
1582                 if (!dentry) {
1583                         /*
1584                          * this is can be hit on boot when a file is accessed
1585                          * before the policy is loaded.  When we load policy we
1586                          * may find inodes that have no dentry on the
1587                          * sbsec->isec_head list.  No reason to complain as these
1588                          * will get fixed up the next time we go through
1589                          * inode_doinit with a dentry, before these inodes could
1590                          * be used again by userspace.
1591                          */
1592                         goto out;
1593                 }
1594
1595                 len = INITCONTEXTLEN;
1596                 context = kmalloc(len+1, GFP_NOFS);
1597                 if (!context) {
1598                         rc = -ENOMEM;
1599                         dput(dentry);
1600                         goto out;
1601                 }
1602                 context[len] = '\0';
1603                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1604                 if (rc == -ERANGE) {
1605                         kfree(context);
1606
1607                         /* Need a larger buffer.  Query for the right size. */
1608                         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1609                         if (rc < 0) {
1610                                 dput(dentry);
1611                                 goto out;
1612                         }
1613                         len = rc;
1614                         context = kmalloc(len+1, GFP_NOFS);
1615                         if (!context) {
1616                                 rc = -ENOMEM;
1617                                 dput(dentry);
1618                                 goto out;
1619                         }
1620                         context[len] = '\0';
1621                         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1622                 }
1623                 dput(dentry);
1624                 if (rc < 0) {
1625                         if (rc != -ENODATA) {
1626                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1627                                        "%d for dev=%s ino=%ld\n", __func__,
1628                                        -rc, inode->i_sb->s_id, inode->i_ino);
1629                                 kfree(context);
1630                                 goto out;
1631                         }
1632                         /* Map ENODATA to the default file SID */
1633                         sid = sbsec->def_sid;
1634                         rc = 0;
1635                 } else {
1636                         rc = security_context_to_sid_default(&selinux_state,
1637                                                              context, rc, &sid,
1638                                                              sbsec->def_sid,
1639                                                              GFP_NOFS);
1640                         if (rc) {
1641                                 char *dev = inode->i_sb->s_id;
1642                                 unsigned long ino = inode->i_ino;
1643
1644                                 if (rc == -EINVAL) {
1645                                         if (printk_ratelimit())
1646                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1647                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1648                                                         "filesystem in question.\n", ino, dev, context);
1649                                 } else {
1650                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1651                                                "returned %d for dev=%s ino=%ld\n",
1652                                                __func__, context, -rc, dev, ino);
1653                                 }
1654                                 kfree(context);
1655                                 /* Leave with the unlabeled SID */
1656                                 rc = 0;
1657                                 break;
1658                         }
1659                 }
1660                 kfree(context);
1661                 break;
1662         case SECURITY_FS_USE_TASK:
1663                 sid = task_sid;
1664                 break;
1665         case SECURITY_FS_USE_TRANS:
1666                 /* Default to the fs SID. */
1667                 sid = sbsec->sid;
1668
1669                 /* Try to obtain a transition SID. */
1670                 rc = security_transition_sid(&selinux_state, task_sid, sid,
1671                                              sclass, NULL, &sid);
1672                 if (rc)
1673                         goto out;
1674                 break;
1675         case SECURITY_FS_USE_MNTPOINT:
1676                 sid = sbsec->mntpoint_sid;
1677                 break;
1678         default:
1679                 /* Default to the fs superblock SID. */
1680                 sid = sbsec->sid;
1681
1682                 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1683                         /* We must have a dentry to determine the label on
1684                          * procfs inodes */
1685                         if (opt_dentry) {
1686                                 /* Called from d_instantiate or
1687                                  * d_splice_alias. */
1688                                 dentry = dget(opt_dentry);
1689                         } else {
1690                                 /* Called from selinux_complete_init, try to
1691                                  * find a dentry.  Some filesystems really want
1692                                  * a connected one, so try that first.
1693                                  */
1694                                 dentry = d_find_alias(inode);
1695                                 if (!dentry)
1696                                         dentry = d_find_any_alias(inode);
1697                         }
1698                         /*
1699                          * This can be hit on boot when a file is accessed
1700                          * before the policy is loaded.  When we load policy we
1701                          * may find inodes that have no dentry on the
1702                          * sbsec->isec_head list.  No reason to complain as
1703                          * these will get fixed up the next time we go through
1704                          * inode_doinit() with a dentry, before these inodes
1705                          * could be used again by userspace.
1706                          */
1707                         if (!dentry)
1708                                 goto out;
1709                         rc = selinux_genfs_get_sid(dentry, sclass,
1710                                                    sbsec->flags, &sid);
1711                         dput(dentry);
1712                         if (rc)
1713                                 goto out;
1714                 }
1715                 break;
1716         }
1717
1718 out:
1719         spin_lock(&isec->lock);
1720         if (isec->initialized == LABEL_PENDING) {
1721                 if (!sid || rc) {
1722                         isec->initialized = LABEL_INVALID;
1723                         goto out_unlock;
1724                 }
1725
1726                 isec->initialized = LABEL_INITIALIZED;
1727                 isec->sid = sid;
1728         }
1729
1730 out_unlock:
1731         spin_unlock(&isec->lock);
1732         return rc;
1733 }
1734
1735 /* Convert a Linux signal to an access vector. */
1736 static inline u32 signal_to_av(int sig)
1737 {
1738         u32 perm = 0;
1739
1740         switch (sig) {
1741         case SIGCHLD:
1742                 /* Commonly granted from child to parent. */
1743                 perm = PROCESS__SIGCHLD;
1744                 break;
1745         case SIGKILL:
1746                 /* Cannot be caught or ignored */
1747                 perm = PROCESS__SIGKILL;
1748                 break;
1749         case SIGSTOP:
1750                 /* Cannot be caught or ignored */
1751                 perm = PROCESS__SIGSTOP;
1752                 break;
1753         default:
1754                 /* All other signals. */
1755                 perm = PROCESS__SIGNAL;
1756                 break;
1757         }
1758
1759         return perm;
1760 }
1761
1762 #if CAP_LAST_CAP > 63
1763 #error Fix SELinux to handle capabilities > 63.
1764 #endif
1765
1766 /* Check whether a task is allowed to use a capability. */
1767 static int cred_has_capability(const struct cred *cred,
1768                                int cap, int audit, bool initns)
1769 {
1770         struct common_audit_data ad;
1771         struct av_decision avd;
1772         u16 sclass;
1773         u32 sid = cred_sid(cred);
1774         u32 av = CAP_TO_MASK(cap);
1775         int rc;
1776
1777         ad.type = LSM_AUDIT_DATA_CAP;
1778         ad.u.cap = cap;
1779
1780         switch (CAP_TO_INDEX(cap)) {
1781         case 0:
1782                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1783                 break;
1784         case 1:
1785                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1786                 break;
1787         default:
1788                 printk(KERN_ERR
1789                        "SELinux:  out of range capability %d\n", cap);
1790                 BUG();
1791                 return -EINVAL;
1792         }
1793
1794         rc = avc_has_perm_noaudit(&selinux_state,
1795                                   sid, sid, sclass, av, 0, &avd);
1796         if (audit == SECURITY_CAP_AUDIT) {
1797                 int rc2 = avc_audit(&selinux_state,
1798                                     sid, sid, sclass, av, &avd, rc, &ad, 0);
1799                 if (rc2)
1800                         return rc2;
1801         }
1802         return rc;
1803 }
1804
1805 /* Check whether a task has a particular permission to an inode.
1806    The 'adp' parameter is optional and allows other audit
1807    data to be passed (e.g. the dentry). */
1808 static int inode_has_perm(const struct cred *cred,
1809                           struct inode *inode,
1810                           u32 perms,
1811                           struct common_audit_data *adp)
1812 {
1813         struct inode_security_struct *isec;
1814         u32 sid;
1815
1816         validate_creds(cred);
1817
1818         if (unlikely(IS_PRIVATE(inode)))
1819                 return 0;
1820
1821         sid = cred_sid(cred);
1822         isec = inode->i_security;
1823
1824         return avc_has_perm(&selinux_state,
1825                             sid, isec->sid, isec->sclass, perms, adp);
1826 }
1827
1828 /* Same as inode_has_perm, but pass explicit audit data containing
1829    the dentry to help the auditing code to more easily generate the
1830    pathname if needed. */
1831 static inline int dentry_has_perm(const struct cred *cred,
1832                                   struct dentry *dentry,
1833                                   u32 av)
1834 {
1835         struct inode *inode = d_backing_inode(dentry);
1836         struct common_audit_data ad;
1837
1838         ad.type = LSM_AUDIT_DATA_DENTRY;
1839         ad.u.dentry = dentry;
1840         __inode_security_revalidate(inode, dentry, true);
1841         return inode_has_perm(cred, inode, av, &ad);
1842 }
1843
1844 /* Same as inode_has_perm, but pass explicit audit data containing
1845    the path to help the auditing code to more easily generate the
1846    pathname if needed. */
1847 static inline int path_has_perm(const struct cred *cred,
1848                                 const struct path *path,
1849                                 u32 av)
1850 {
1851         struct inode *inode = d_backing_inode(path->dentry);
1852         struct common_audit_data ad;
1853
1854         ad.type = LSM_AUDIT_DATA_PATH;
1855         ad.u.path = *path;
1856         __inode_security_revalidate(inode, path->dentry, true);
1857         return inode_has_perm(cred, inode, av, &ad);
1858 }
1859
1860 /* Same as path_has_perm, but uses the inode from the file struct. */
1861 static inline int file_path_has_perm(const struct cred *cred,
1862                                      struct file *file,
1863                                      u32 av)
1864 {
1865         struct common_audit_data ad;
1866
1867         ad.type = LSM_AUDIT_DATA_FILE;
1868         ad.u.file = file;
1869         return inode_has_perm(cred, file_inode(file), av, &ad);
1870 }
1871
1872 #ifdef CONFIG_BPF_SYSCALL
1873 static int bpf_fd_pass(struct file *file, u32 sid);
1874 #endif
1875
1876 /* Check whether a task can use an open file descriptor to
1877    access an inode in a given way.  Check access to the
1878    descriptor itself, and then use dentry_has_perm to
1879    check a particular permission to the file.
1880    Access to the descriptor is implicitly granted if it
1881    has the same SID as the process.  If av is zero, then
1882    access to the file is not checked, e.g. for cases
1883    where only the descriptor is affected like seek. */
1884 static int file_has_perm(const struct cred *cred,
1885                          struct file *file,
1886                          u32 av)
1887 {
1888         struct file_security_struct *fsec = file->f_security;
1889         struct inode *inode = file_inode(file);
1890         struct common_audit_data ad;
1891         u32 sid = cred_sid(cred);
1892         int rc;
1893
1894         ad.type = LSM_AUDIT_DATA_FILE;
1895         ad.u.file = file;
1896
1897         if (sid != fsec->sid) {
1898                 rc = avc_has_perm(&selinux_state,
1899                                   sid, fsec->sid,
1900                                   SECCLASS_FD,
1901                                   FD__USE,
1902                                   &ad);
1903                 if (rc)
1904                         goto out;
1905         }
1906
1907 #ifdef CONFIG_BPF_SYSCALL
1908         rc = bpf_fd_pass(file, cred_sid(cred));
1909         if (rc)
1910                 return rc;
1911 #endif
1912
1913         /* av is zero if only checking access to the descriptor. */
1914         rc = 0;
1915         if (av)
1916                 rc = inode_has_perm(cred, inode, av, &ad);
1917
1918 out:
1919         return rc;
1920 }
1921
1922 /*
1923  * Determine the label for an inode that might be unioned.
1924  */
1925 static int
1926 selinux_determine_inode_label(const struct task_security_struct *tsec,
1927                                  struct inode *dir,
1928                                  const struct qstr *name, u16 tclass,
1929                                  u32 *_new_isid)
1930 {
1931         const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1932
1933         if ((sbsec->flags & SE_SBINITIALIZED) &&
1934             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1935                 *_new_isid = sbsec->mntpoint_sid;
1936         } else if ((sbsec->flags & SBLABEL_MNT) &&
1937                    tsec->create_sid) {
1938                 *_new_isid = tsec->create_sid;
1939         } else {
1940                 const struct inode_security_struct *dsec = inode_security(dir);
1941                 return security_transition_sid(&selinux_state, tsec->sid,
1942                                                dsec->sid, tclass,
1943                                                name, _new_isid);
1944         }
1945
1946         return 0;
1947 }
1948
1949 /* Check whether a task can create a file. */
1950 static int may_create(struct inode *dir,
1951                       struct dentry *dentry,
1952                       u16 tclass)
1953 {
1954         const struct task_security_struct *tsec = current_security();
1955         struct inode_security_struct *dsec;
1956         struct superblock_security_struct *sbsec;
1957         u32 sid, newsid;
1958         struct common_audit_data ad;
1959         int rc;
1960
1961         dsec = inode_security(dir);
1962         sbsec = dir->i_sb->s_security;
1963
1964         sid = tsec->sid;
1965
1966         ad.type = LSM_AUDIT_DATA_DENTRY;
1967         ad.u.dentry = dentry;
1968
1969         rc = avc_has_perm(&selinux_state,
1970                           sid, dsec->sid, SECCLASS_DIR,
1971                           DIR__ADD_NAME | DIR__SEARCH,
1972                           &ad);
1973         if (rc)
1974                 return rc;
1975
1976         rc = selinux_determine_inode_label(current_security(), dir,
1977                                            &dentry->d_name, tclass, &newsid);
1978         if (rc)
1979                 return rc;
1980
1981         rc = avc_has_perm(&selinux_state,
1982                           sid, newsid, tclass, FILE__CREATE, &ad);
1983         if (rc)
1984                 return rc;
1985
1986         return avc_has_perm(&selinux_state,
1987                             newsid, sbsec->sid,
1988                             SECCLASS_FILESYSTEM,
1989                             FILESYSTEM__ASSOCIATE, &ad);
1990 }
1991
1992 #define MAY_LINK        0
1993 #define MAY_UNLINK      1
1994 #define MAY_RMDIR       2
1995
1996 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1997 static int may_link(struct inode *dir,
1998                     struct dentry *dentry,
1999                     int kind)
2000
2001 {
2002         struct inode_security_struct *dsec, *isec;
2003         struct common_audit_data ad;
2004         u32 sid = current_sid();
2005         u32 av;
2006         int rc;
2007
2008         dsec = inode_security(dir);
2009         isec = backing_inode_security(dentry);
2010
2011         ad.type = LSM_AUDIT_DATA_DENTRY;
2012         ad.u.dentry = dentry;
2013
2014         av = DIR__SEARCH;
2015         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
2016         rc = avc_has_perm(&selinux_state,
2017                           sid, dsec->sid, SECCLASS_DIR, av, &ad);
2018         if (rc)
2019                 return rc;
2020
2021         switch (kind) {
2022         case MAY_LINK:
2023                 av = FILE__LINK;
2024                 break;
2025         case MAY_UNLINK:
2026                 av = FILE__UNLINK;
2027                 break;
2028         case MAY_RMDIR:
2029                 av = DIR__RMDIR;
2030                 break;
2031         default:
2032                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
2033                         __func__, kind);
2034                 return 0;
2035         }
2036
2037         rc = avc_has_perm(&selinux_state,
2038                           sid, isec->sid, isec->sclass, av, &ad);
2039         return rc;
2040 }
2041
2042 static inline int may_rename(struct inode *old_dir,
2043                              struct dentry *old_dentry,
2044                              struct inode *new_dir,
2045                              struct dentry *new_dentry)
2046 {
2047         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
2048         struct common_audit_data ad;
2049         u32 sid = current_sid();
2050         u32 av;
2051         int old_is_dir, new_is_dir;
2052         int rc;
2053
2054         old_dsec = inode_security(old_dir);
2055         old_isec = backing_inode_security(old_dentry);
2056         old_is_dir = d_is_dir(old_dentry);
2057         new_dsec = inode_security(new_dir);
2058
2059         ad.type = LSM_AUDIT_DATA_DENTRY;
2060
2061         ad.u.dentry = old_dentry;
2062         rc = avc_has_perm(&selinux_state,
2063                           sid, old_dsec->sid, SECCLASS_DIR,
2064                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
2065         if (rc)
2066                 return rc;
2067         rc = avc_has_perm(&selinux_state,
2068                           sid, old_isec->sid,
2069                           old_isec->sclass, FILE__RENAME, &ad);
2070         if (rc)
2071                 return rc;
2072         if (old_is_dir && new_dir != old_dir) {
2073                 rc = avc_has_perm(&selinux_state,
2074                                   sid, old_isec->sid,
2075                                   old_isec->sclass, DIR__REPARENT, &ad);
2076                 if (rc)
2077                         return rc;
2078         }
2079
2080         ad.u.dentry = new_dentry;
2081         av = DIR__ADD_NAME | DIR__SEARCH;
2082         if (d_is_positive(new_dentry))
2083                 av |= DIR__REMOVE_NAME;
2084         rc = avc_has_perm(&selinux_state,
2085                           sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
2086         if (rc)
2087                 return rc;
2088         if (d_is_positive(new_dentry)) {
2089                 new_isec = backing_inode_security(new_dentry);
2090                 new_is_dir = d_is_dir(new_dentry);
2091                 rc = avc_has_perm(&selinux_state,
2092                                   sid, new_isec->sid,
2093                                   new_isec->sclass,
2094                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
2095                 if (rc)
2096                         return rc;
2097         }
2098
2099         return 0;
2100 }
2101
2102 /* Check whether a task can perform a filesystem operation. */
2103 static int superblock_has_perm(const struct cred *cred,
2104                                struct super_block *sb,
2105                                u32 perms,
2106                                struct common_audit_data *ad)
2107 {
2108         struct superblock_security_struct *sbsec;
2109         u32 sid = cred_sid(cred);
2110
2111         sbsec = sb->s_security;
2112         return avc_has_perm(&selinux_state,
2113                             sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
2114 }
2115
2116 /* Convert a Linux mode and permission mask to an access vector. */
2117 static inline u32 file_mask_to_av(int mode, int mask)
2118 {
2119         u32 av = 0;
2120
2121         if (!S_ISDIR(mode)) {
2122                 if (mask & MAY_EXEC)
2123                         av |= FILE__EXECUTE;
2124                 if (mask & MAY_READ)
2125                         av |= FILE__READ;
2126
2127                 if (mask & MAY_APPEND)
2128                         av |= FILE__APPEND;
2129                 else if (mask & MAY_WRITE)
2130                         av |= FILE__WRITE;
2131
2132         } else {
2133                 if (mask & MAY_EXEC)
2134                         av |= DIR__SEARCH;
2135                 if (mask & MAY_WRITE)
2136                         av |= DIR__WRITE;
2137                 if (mask & MAY_READ)
2138                         av |= DIR__READ;
2139         }
2140
2141         return av;
2142 }
2143
2144 /* Convert a Linux file to an access vector. */
2145 static inline u32 file_to_av(struct file *file)
2146 {
2147         u32 av = 0;
2148
2149         if (file->f_mode & FMODE_READ)
2150                 av |= FILE__READ;
2151         if (file->f_mode & FMODE_WRITE) {
2152                 if (file->f_flags & O_APPEND)
2153                         av |= FILE__APPEND;
2154                 else
2155                         av |= FILE__WRITE;
2156         }
2157         if (!av) {
2158                 /*
2159                  * Special file opened with flags 3 for ioctl-only use.
2160                  */
2161                 av = FILE__IOCTL;
2162         }
2163
2164         return av;
2165 }
2166
2167 /*
2168  * Convert a file to an access vector and include the correct open
2169  * open permission.
2170  */
2171 static inline u32 open_file_to_av(struct file *file)
2172 {
2173         u32 av = file_to_av(file);
2174         struct inode *inode = file_inode(file);
2175
2176         if (selinux_policycap_openperm() &&
2177             inode->i_sb->s_magic != SOCKFS_MAGIC)
2178                 av |= FILE__OPEN;
2179
2180         return av;
2181 }
2182
2183 /* Hook functions begin here. */
2184
2185 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2186 {
2187         u32 mysid = current_sid();
2188         u32 mgrsid = task_sid(mgr);
2189
2190         return avc_has_perm(&selinux_state,
2191                             mysid, mgrsid, SECCLASS_BINDER,
2192                             BINDER__SET_CONTEXT_MGR, NULL);
2193 }
2194
2195 static int selinux_binder_transaction(struct task_struct *from,
2196                                       struct task_struct *to)
2197 {
2198         u32 mysid = current_sid();
2199         u32 fromsid = task_sid(from);
2200         u32 tosid = task_sid(to);
2201         int rc;
2202
2203         if (mysid != fromsid) {
2204                 rc = avc_has_perm(&selinux_state,
2205                                   mysid, fromsid, SECCLASS_BINDER,
2206                                   BINDER__IMPERSONATE, NULL);
2207                 if (rc)
2208                         return rc;
2209         }
2210
2211         return avc_has_perm(&selinux_state,
2212                             fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2213                             NULL);
2214 }
2215
2216 static int selinux_binder_transfer_binder(struct task_struct *from,
2217                                           struct task_struct *to)
2218 {
2219         u32 fromsid = task_sid(from);
2220         u32 tosid = task_sid(to);
2221
2222         return avc_has_perm(&selinux_state,
2223                             fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2224                             NULL);
2225 }
2226
2227 static int selinux_binder_transfer_file(struct task_struct *from,
2228                                         struct task_struct *to,
2229                                         struct file *file)
2230 {
2231         u32 sid = task_sid(to);
2232         struct file_security_struct *fsec = file->f_security;
2233         struct dentry *dentry = file->f_path.dentry;
2234         struct inode_security_struct *isec;
2235         struct common_audit_data ad;
2236         int rc;
2237
2238         ad.type = LSM_AUDIT_DATA_PATH;
2239         ad.u.path = file->f_path;
2240
2241         if (sid != fsec->sid) {
2242                 rc = avc_has_perm(&selinux_state,
2243                                   sid, fsec->sid,
2244                                   SECCLASS_FD,
2245                                   FD__USE,
2246                                   &ad);
2247                 if (rc)
2248                         return rc;
2249         }
2250
2251 #ifdef CONFIG_BPF_SYSCALL
2252         rc = bpf_fd_pass(file, sid);
2253         if (rc)
2254                 return rc;
2255 #endif
2256
2257         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2258                 return 0;
2259
2260         isec = backing_inode_security(dentry);
2261         return avc_has_perm(&selinux_state,
2262                             sid, isec->sid, isec->sclass, file_to_av(file),
2263                             &ad);
2264 }
2265
2266 static int selinux_ptrace_access_check(struct task_struct *child,
2267                                      unsigned int mode)
2268 {
2269         u32 sid = current_sid();
2270         u32 csid = task_sid(child);
2271
2272         if (mode & PTRACE_MODE_READ)
2273                 return avc_has_perm(&selinux_state,
2274                                     sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2275
2276         return avc_has_perm(&selinux_state,
2277                             sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2278 }
2279
2280 static int selinux_ptrace_traceme(struct task_struct *parent)
2281 {
2282         return avc_has_perm(&selinux_state,
2283                             task_sid(parent), current_sid(), SECCLASS_PROCESS,
2284                             PROCESS__PTRACE, NULL);
2285 }
2286
2287 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2288                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2289 {
2290         return avc_has_perm(&selinux_state,
2291                             current_sid(), task_sid(target), SECCLASS_PROCESS,
2292                             PROCESS__GETCAP, NULL);
2293 }
2294
2295 static int selinux_capset(struct cred *new, const struct cred *old,
2296                           const kernel_cap_t *effective,
2297                           const kernel_cap_t *inheritable,
2298                           const kernel_cap_t *permitted)
2299 {
2300         return avc_has_perm(&selinux_state,
2301                             cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2302                             PROCESS__SETCAP, NULL);
2303 }
2304
2305 /*
2306  * (This comment used to live with the selinux_task_setuid hook,
2307  * which was removed).
2308  *
2309  * Since setuid only affects the current process, and since the SELinux
2310  * controls are not based on the Linux identity attributes, SELinux does not
2311  * need to control this operation.  However, SELinux does control the use of
2312  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2313  */
2314
2315 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2316                            int cap, int audit)
2317 {
2318         return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2319 }
2320
2321 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2322 {
2323         const struct cred *cred = current_cred();
2324         int rc = 0;
2325
2326         if (!sb)
2327                 return 0;
2328
2329         switch (cmds) {
2330         case Q_SYNC:
2331         case Q_QUOTAON:
2332         case Q_QUOTAOFF:
2333         case Q_SETINFO:
2334         case Q_SETQUOTA:
2335                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2336                 break;
2337         case Q_GETFMT:
2338         case Q_GETINFO:
2339         case Q_GETQUOTA:
2340                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2341                 break;
2342         default:
2343                 rc = 0;  /* let the kernel handle invalid cmds */
2344                 break;
2345         }
2346         return rc;
2347 }
2348
2349 static int selinux_quota_on(struct dentry *dentry)
2350 {
2351         const struct cred *cred = current_cred();
2352
2353         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2354 }
2355
2356 static int selinux_syslog(int type)
2357 {
2358         switch (type) {
2359         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2360         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2361                 return avc_has_perm(&selinux_state,
2362                                     current_sid(), SECINITSID_KERNEL,
2363                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2364         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2365         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2366         /* Set level of messages printed to console */
2367         case SYSLOG_ACTION_CONSOLE_LEVEL:
2368                 return avc_has_perm(&selinux_state,
2369                                     current_sid(), SECINITSID_KERNEL,
2370                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2371                                     NULL);
2372         }
2373         /* All other syslog types */
2374         return avc_has_perm(&selinux_state,
2375                             current_sid(), SECINITSID_KERNEL,
2376                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2377 }
2378
2379 /*
2380  * Check that a process has enough memory to allocate a new virtual
2381  * mapping. 0 means there is enough memory for the allocation to
2382  * succeed and -ENOMEM implies there is not.
2383  *
2384  * Do not audit the selinux permission check, as this is applied to all
2385  * processes that allocate mappings.
2386  */
2387 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2388 {
2389         int rc, cap_sys_admin = 0;
2390
2391         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2392                                  SECURITY_CAP_NOAUDIT, true);
2393         if (rc == 0)
2394                 cap_sys_admin = 1;
2395
2396         return cap_sys_admin;
2397 }
2398
2399 /* binprm security operations */
2400
2401 static u32 ptrace_parent_sid(void)
2402 {
2403         u32 sid = 0;
2404         struct task_struct *tracer;
2405
2406         rcu_read_lock();
2407         tracer = ptrace_parent(current);
2408         if (tracer)
2409                 sid = task_sid(tracer);
2410         rcu_read_unlock();
2411
2412         return sid;
2413 }
2414
2415 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2416                             const struct task_security_struct *old_tsec,
2417                             const struct task_security_struct *new_tsec)
2418 {
2419         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2420         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2421         int rc;
2422         u32 av;
2423
2424         if (!nnp && !nosuid)
2425                 return 0; /* neither NNP nor nosuid */
2426
2427         if (new_tsec->sid == old_tsec->sid)
2428                 return 0; /* No change in credentials */
2429
2430         /*
2431          * If the policy enables the nnp_nosuid_transition policy capability,
2432          * then we permit transitions under NNP or nosuid if the
2433          * policy allows the corresponding permission between
2434          * the old and new contexts.
2435          */
2436         if (selinux_policycap_nnp_nosuid_transition()) {
2437                 av = 0;
2438                 if (nnp)
2439                         av |= PROCESS2__NNP_TRANSITION;
2440                 if (nosuid)
2441                         av |= PROCESS2__NOSUID_TRANSITION;
2442                 rc = avc_has_perm(&selinux_state,
2443                                   old_tsec->sid, new_tsec->sid,
2444                                   SECCLASS_PROCESS2, av, NULL);
2445                 if (!rc)
2446                         return 0;
2447         }
2448
2449         /*
2450          * We also permit NNP or nosuid transitions to bounded SIDs,
2451          * i.e. SIDs that are guaranteed to only be allowed a subset
2452          * of the permissions of the current SID.
2453          */
2454         rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2455                                          new_tsec->sid);
2456         if (!rc)
2457                 return 0;
2458
2459         /*
2460          * On failure, preserve the errno values for NNP vs nosuid.
2461          * NNP:  Operation not permitted for caller.
2462          * nosuid:  Permission denied to file.
2463          */
2464         if (nnp)
2465                 return -EPERM;
2466         return -EACCES;
2467 }
2468
2469 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2470 {
2471         const struct task_security_struct *old_tsec;
2472         struct task_security_struct *new_tsec;
2473         struct inode_security_struct *isec;
2474         struct common_audit_data ad;
2475         struct inode *inode = file_inode(bprm->file);
2476         int rc;
2477
2478         /* SELinux context only depends on initial program or script and not
2479          * the script interpreter */
2480         if (bprm->called_set_creds)
2481                 return 0;
2482
2483         old_tsec = current_security();
2484         new_tsec = bprm->cred->security;
2485         isec = inode_security(inode);
2486
2487         /* Default to the current task SID. */
2488         new_tsec->sid = old_tsec->sid;
2489         new_tsec->osid = old_tsec->sid;
2490
2491         /* Reset fs, key, and sock SIDs on execve. */
2492         new_tsec->create_sid = 0;
2493         new_tsec->keycreate_sid = 0;
2494         new_tsec->sockcreate_sid = 0;
2495
2496         if (old_tsec->exec_sid) {
2497                 new_tsec->sid = old_tsec->exec_sid;
2498                 /* Reset exec SID on execve. */
2499                 new_tsec->exec_sid = 0;
2500
2501                 /* Fail on NNP or nosuid if not an allowed transition. */
2502                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2503                 if (rc)
2504                         return rc;
2505         } else {
2506                 /* Check for a default transition on this program. */
2507                 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2508                                              isec->sid, SECCLASS_PROCESS, NULL,
2509                                              &new_tsec->sid);
2510                 if (rc)
2511                         return rc;
2512
2513                 /*
2514                  * Fallback to old SID on NNP or nosuid if not an allowed
2515                  * transition.
2516                  */
2517                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2518                 if (rc)
2519                         new_tsec->sid = old_tsec->sid;
2520         }
2521
2522         ad.type = LSM_AUDIT_DATA_FILE;
2523         ad.u.file = bprm->file;
2524
2525         if (new_tsec->sid == old_tsec->sid) {
2526                 rc = avc_has_perm(&selinux_state,
2527                                   old_tsec->sid, isec->sid,
2528                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2529                 if (rc)
2530                         return rc;
2531         } else {
2532                 /* Check permissions for the transition. */
2533                 rc = avc_has_perm(&selinux_state,
2534                                   old_tsec->sid, new_tsec->sid,
2535                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2536                 if (rc)
2537                         return rc;
2538
2539                 rc = avc_has_perm(&selinux_state,
2540                                   new_tsec->sid, isec->sid,
2541                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2542                 if (rc)
2543                         return rc;
2544
2545                 /* Check for shared state */
2546                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2547                         rc = avc_has_perm(&selinux_state,
2548                                           old_tsec->sid, new_tsec->sid,
2549                                           SECCLASS_PROCESS, PROCESS__SHARE,
2550                                           NULL);
2551                         if (rc)
2552                                 return -EPERM;
2553                 }
2554
2555                 /* Make sure that anyone attempting to ptrace over a task that
2556                  * changes its SID has the appropriate permit */
2557                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2558                         u32 ptsid = ptrace_parent_sid();
2559                         if (ptsid != 0) {
2560                                 rc = avc_has_perm(&selinux_state,
2561                                                   ptsid, new_tsec->sid,
2562                                                   SECCLASS_PROCESS,
2563                                                   PROCESS__PTRACE, NULL);
2564                                 if (rc)
2565                                         return -EPERM;
2566                         }
2567                 }
2568
2569                 /* Clear any possibly unsafe personality bits on exec: */
2570                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2571
2572                 /* Enable secure mode for SIDs transitions unless
2573                    the noatsecure permission is granted between
2574                    the two SIDs, i.e. ahp returns 0. */
2575                 rc = avc_has_perm(&selinux_state,
2576                                   old_tsec->sid, new_tsec->sid,
2577                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2578                                   NULL);
2579                 bprm->secureexec |= !!rc;
2580         }
2581
2582         return 0;
2583 }
2584
2585 static int match_file(const void *p, struct file *file, unsigned fd)
2586 {
2587         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2588 }
2589
2590 /* Derived from fs/exec.c:flush_old_files. */
2591 static inline void flush_unauthorized_files(const struct cred *cred,
2592                                             struct files_struct *files)
2593 {
2594         struct file *file, *devnull = NULL;
2595         struct tty_struct *tty;
2596         int drop_tty = 0;
2597         unsigned n;
2598
2599         tty = get_current_tty();
2600         if (tty) {
2601                 spin_lock(&tty->files_lock);
2602                 if (!list_empty(&tty->tty_files)) {
2603                         struct tty_file_private *file_priv;
2604
2605                         /* Revalidate access to controlling tty.
2606                            Use file_path_has_perm on the tty path directly
2607                            rather than using file_has_perm, as this particular
2608                            open file may belong to another process and we are
2609                            only interested in the inode-based check here. */
2610                         file_priv = list_first_entry(&tty->tty_files,
2611                                                 struct tty_file_private, list);
2612                         file = file_priv->file;
2613                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2614                                 drop_tty = 1;
2615                 }
2616                 spin_unlock(&tty->files_lock);
2617                 tty_kref_put(tty);
2618         }
2619         /* Reset controlling tty. */
2620         if (drop_tty)
2621                 no_tty();
2622
2623         /* Revalidate access to inherited open files. */
2624         n = iterate_fd(files, 0, match_file, cred);
2625         if (!n) /* none found? */
2626                 return;
2627
2628         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2629         if (IS_ERR(devnull))
2630                 devnull = NULL;
2631         /* replace all the matching ones with this */
2632         do {
2633                 replace_fd(n - 1, devnull, 0);
2634         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2635         if (devnull)
2636                 fput(devnull);
2637 }
2638
2639 /*
2640  * Prepare a process for imminent new credential changes due to exec
2641  */
2642 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2643 {
2644         struct task_security_struct *new_tsec;
2645         struct rlimit *rlim, *initrlim;
2646         int rc, i;
2647
2648         new_tsec = bprm->cred->security;
2649         if (new_tsec->sid == new_tsec->osid)
2650                 return;
2651
2652         /* Close files for which the new task SID is not authorized. */
2653         flush_unauthorized_files(bprm->cred, current->files);
2654
2655         /* Always clear parent death signal on SID transitions. */
2656         current->pdeath_signal = 0;
2657
2658         /* Check whether the new SID can inherit resource limits from the old
2659          * SID.  If not, reset all soft limits to the lower of the current
2660          * task's hard limit and the init task's soft limit.
2661          *
2662          * Note that the setting of hard limits (even to lower them) can be
2663          * controlled by the setrlimit check.  The inclusion of the init task's
2664          * soft limit into the computation is to avoid resetting soft limits
2665          * higher than the default soft limit for cases where the default is
2666          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2667          */
2668         rc = avc_has_perm(&selinux_state,
2669                           new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2670                           PROCESS__RLIMITINH, NULL);
2671         if (rc) {
2672                 /* protect against do_prlimit() */
2673                 task_lock(current);
2674                 for (i = 0; i < RLIM_NLIMITS; i++) {
2675                         rlim = current->signal->rlim + i;
2676                         initrlim = init_task.signal->rlim + i;
2677                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2678                 }
2679                 task_unlock(current);
2680                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2681                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2682         }
2683 }
2684
2685 /*
2686  * Clean up the process immediately after the installation of new credentials
2687  * due to exec
2688  */
2689 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2690 {
2691         const struct task_security_struct *tsec = current_security();
2692         struct itimerval itimer;
2693         u32 osid, sid;
2694         int rc, i;
2695
2696         osid = tsec->osid;
2697         sid = tsec->sid;
2698
2699         if (sid == osid)
2700                 return;
2701
2702         /* Check whether the new SID can inherit signal state from the old SID.
2703          * If not, clear itimers to avoid subsequent signal generation and
2704          * flush and unblock signals.
2705          *
2706          * This must occur _after_ the task SID has been updated so that any
2707          * kill done after the flush will be checked against the new SID.
2708          */
2709         rc = avc_has_perm(&selinux_state,
2710                           osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2711         if (rc) {
2712                 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2713                         memset(&itimer, 0, sizeof itimer);
2714                         for (i = 0; i < 3; i++)
2715                                 do_setitimer(i, &itimer, NULL);
2716                 }
2717                 spin_lock_irq(&current->sighand->siglock);
2718                 if (!fatal_signal_pending(current)) {
2719                         flush_sigqueue(&current->pending);
2720                         flush_sigqueue(&current->signal->shared_pending);
2721                         flush_signal_handlers(current, 1);
2722                         sigemptyset(&current->blocked);
2723                         recalc_sigpending();
2724                 }
2725                 spin_unlock_irq(&current->sighand->siglock);
2726         }
2727
2728         /* Wake up the parent if it is waiting so that it can recheck
2729          * wait permission to the new task SID. */
2730         read_lock(&tasklist_lock);
2731         __wake_up_parent(current, current->real_parent);
2732         read_unlock(&tasklist_lock);
2733 }
2734
2735 /* superblock security operations */
2736
2737 static int selinux_sb_alloc_security(struct super_block *sb)
2738 {
2739         return superblock_alloc_security(sb);
2740 }
2741
2742 static void selinux_sb_free_security(struct super_block *sb)
2743 {
2744         superblock_free_security(sb);
2745 }
2746
2747 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2748 {
2749         if (plen > olen)
2750                 return 0;
2751
2752         return !memcmp(prefix, option, plen);
2753 }
2754
2755 static inline int selinux_option(char *option, int len)
2756 {
2757         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2758                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2759                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2760                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2761                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2762 }
2763
2764 static inline void take_option(char **to, char *from, int *first, int len)
2765 {
2766         if (!*first) {
2767                 **to = ',';
2768                 *to += 1;
2769         } else
2770                 *first = 0;
2771         memcpy(*to, from, len);
2772         *to += len;
2773 }
2774
2775 static inline void take_selinux_option(char **to, char *from, int *first,
2776                                        int len)
2777 {
2778         int current_size = 0;
2779
2780         if (!*first) {
2781                 **to = '|';
2782                 *to += 1;
2783         } else
2784                 *first = 0;
2785
2786         while (current_size < len) {
2787                 if (*from != '"') {
2788                         **to = *from;
2789                         *to += 1;
2790                 }
2791                 from += 1;
2792                 current_size += 1;
2793         }
2794 }
2795
2796 static int selinux_sb_copy_data(char *orig, char *copy)
2797 {
2798         int fnosec, fsec, rc = 0;
2799         char *in_save, *in_curr, *in_end;
2800         char *sec_curr, *nosec_save, *nosec;
2801         int open_quote = 0;
2802
2803         in_curr = orig;
2804         sec_curr = copy;
2805
2806         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2807         if (!nosec) {
2808                 rc = -ENOMEM;
2809                 goto out;
2810         }
2811
2812         nosec_save = nosec;
2813         fnosec = fsec = 1;
2814         in_save = in_end = orig;
2815
2816         do {
2817                 if (*in_end == '"')
2818                         open_quote = !open_quote;
2819                 if ((*in_end == ',' && open_quote == 0) ||
2820                                 *in_end == '\0') {
2821                         int len = in_end - in_curr;
2822
2823                         if (selinux_option(in_curr, len))
2824                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2825                         else
2826                                 take_option(&nosec, in_curr, &fnosec, len);
2827
2828                         in_curr = in_end + 1;
2829                 }
2830         } while (*in_end++);
2831
2832         strcpy(in_save, nosec_save);
2833         free_page((unsigned long)nosec_save);
2834 out:
2835         return rc;
2836 }
2837
2838 static int selinux_sb_remount(struct super_block *sb, void *data)
2839 {
2840         int rc, i, *flags;
2841         struct security_mnt_opts opts;
2842         char *secdata, **mount_options;
2843         struct superblock_security_struct *sbsec = sb->s_security;
2844
2845         if (!(sbsec->flags & SE_SBINITIALIZED))
2846                 return 0;
2847
2848         if (!data)
2849                 return 0;
2850
2851         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2852                 return 0;
2853
2854         security_init_mnt_opts(&opts);
2855         secdata = alloc_secdata();
2856         if (!secdata)
2857                 return -ENOMEM;
2858         rc = selinux_sb_copy_data(data, secdata);
2859         if (rc)
2860                 goto out_free_secdata;
2861
2862         rc = selinux_parse_opts_str(secdata, &opts);
2863         if (rc)
2864                 goto out_free_secdata;
2865
2866         mount_options = opts.mnt_opts;
2867         flags = opts.mnt_opts_flags;
2868
2869         for (i = 0; i < opts.num_mnt_opts; i++) {
2870                 u32 sid;
2871
2872                 if (flags[i] == SBLABEL_MNT)
2873                         continue;
2874                 rc = security_context_str_to_sid(&selinux_state,
2875                                                  mount_options[i], &sid,
2876                                                  GFP_KERNEL);
2877                 if (rc) {
2878                         printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2879                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2880                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2881                         goto out_free_opts;
2882                 }
2883                 rc = -EINVAL;
2884                 switch (flags[i]) {
2885                 case FSCONTEXT_MNT:
2886                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2887                                 goto out_bad_option;
2888                         break;
2889                 case CONTEXT_MNT:
2890                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2891                                 goto out_bad_option;
2892                         break;
2893                 case ROOTCONTEXT_MNT: {
2894                         struct inode_security_struct *root_isec;
2895                         root_isec = backing_inode_security(sb->s_root);
2896
2897                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2898                                 goto out_bad_option;
2899                         break;
2900                 }
2901                 case DEFCONTEXT_MNT:
2902                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2903                                 goto out_bad_option;
2904                         break;
2905                 default:
2906                         goto out_free_opts;
2907                 }
2908         }
2909
2910         rc = 0;
2911 out_free_opts:
2912         security_free_mnt_opts(&opts);
2913 out_free_secdata:
2914         free_secdata(secdata);
2915         return rc;
2916 out_bad_option:
2917         printk(KERN_WARNING "SELinux: unable to change security options "
2918                "during remount (dev %s, type=%s)\n", sb->s_id,
2919                sb->s_type->name);
2920         goto out_free_opts;
2921 }
2922
2923 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2924 {
2925         const struct cred *cred = current_cred();
2926         struct common_audit_data ad;
2927         int rc;
2928
2929         rc = superblock_doinit(sb, data);
2930         if (rc)
2931                 return rc;
2932
2933         /* Allow all mounts performed by the kernel */
2934         if (flags & MS_KERNMOUNT)
2935                 return 0;
2936
2937         ad.type = LSM_AUDIT_DATA_DENTRY;
2938         ad.u.dentry = sb->s_root;
2939         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2940 }
2941
2942 static int selinux_sb_statfs(struct dentry *dentry)
2943 {
2944         const struct cred *cred = current_cred();
2945         struct common_audit_data ad;
2946
2947         ad.type = LSM_AUDIT_DATA_DENTRY;
2948         ad.u.dentry = dentry->d_sb->s_root;
2949         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2950 }
2951
2952 static int selinux_mount(const char *dev_name,
2953                          const struct path *path,
2954                          const char *type,
2955                          unsigned long flags,
2956                          void *data)
2957 {
2958         const struct cred *cred = current_cred();
2959
2960         if (flags & MS_REMOUNT)
2961                 return superblock_has_perm(cred, path->dentry->d_sb,
2962                                            FILESYSTEM__REMOUNT, NULL);
2963         else
2964                 return path_has_perm(cred, path, FILE__MOUNTON);
2965 }
2966
2967 static int selinux_umount(struct vfsmount *mnt, int flags)
2968 {
2969         const struct cred *cred = current_cred();
2970
2971         return superblock_has_perm(cred, mnt->mnt_sb,
2972                                    FILESYSTEM__UNMOUNT, NULL);
2973 }
2974
2975 /* inode security operations */
2976
2977 static int selinux_inode_alloc_security(struct inode *inode)
2978 {
2979         return inode_alloc_security(inode);
2980 }
2981
2982 static void selinux_inode_free_security(struct inode *inode)
2983 {
2984         inode_free_security(inode);
2985 }
2986
2987 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2988                                         const struct qstr *name, void **ctx,
2989                                         u32 *ctxlen)
2990 {
2991         u32 newsid;
2992         int rc;
2993
2994         rc = selinux_determine_inode_label(current_security(),
2995                                            d_inode(dentry->d_parent), name,
2996                                            inode_mode_to_security_class(mode),
2997                                            &newsid);
2998         if (rc)
2999                 return rc;
3000
3001         return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
3002                                        ctxlen);
3003 }
3004
3005 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
3006                                           struct qstr *name,
3007                                           const struct cred *old,
3008                                           struct cred *new)
3009 {
3010         u32 newsid;
3011         int rc;
3012         struct task_security_struct *tsec;
3013
3014         rc = selinux_determine_inode_label(old->security,
3015                                            d_inode(dentry->d_parent), name,
3016                                            inode_mode_to_security_class(mode),
3017                                            &newsid);
3018         if (rc)
3019                 return rc;
3020
3021         tsec = new->security;
3022         tsec->create_sid = newsid;
3023         return 0;
3024 }
3025
3026 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
3027                                        const struct qstr *qstr,
3028                                        const char **name,
3029                                        void **value, size_t *len)
3030 {
3031         const struct task_security_struct *tsec = current_security();
3032         struct superblock_security_struct *sbsec;
3033         u32 newsid, clen;
3034         int rc;
3035         char *context;
3036
3037         sbsec = dir->i_sb->s_security;
3038
3039         newsid = tsec->create_sid;
3040
3041         rc = selinux_determine_inode_label(current_security(),
3042                 dir, qstr,
3043                 inode_mode_to_security_class(inode->i_mode),
3044                 &newsid);
3045         if (rc)
3046                 return rc;
3047
3048         /* Possibly defer initialization to selinux_complete_init. */
3049         if (sbsec->flags & SE_SBINITIALIZED) {
3050                 struct inode_security_struct *isec = inode->i_security;
3051                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3052                 isec->sid = newsid;
3053                 isec->initialized = LABEL_INITIALIZED;
3054         }
3055
3056         if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT))
3057                 return -EOPNOTSUPP;
3058
3059         if (name)
3060                 *name = XATTR_SELINUX_SUFFIX;
3061
3062         if (value && len) {
3063                 rc = security_sid_to_context_force(&selinux_state, newsid,
3064                                                    &context, &clen);
3065                 if (rc)
3066                         return rc;
3067                 *value = context;
3068                 *len = clen;
3069         }
3070
3071         return 0;
3072 }
3073
3074 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3075 {
3076         return may_create(dir, dentry, SECCLASS_FILE);
3077 }
3078
3079 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3080 {
3081         return may_link(dir, old_dentry, MAY_LINK);
3082 }
3083
3084 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3085 {
3086         return may_link(dir, dentry, MAY_UNLINK);
3087 }
3088
3089 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3090 {
3091         return may_create(dir, dentry, SECCLASS_LNK_FILE);
3092 }
3093
3094 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3095 {
3096         return may_create(dir, dentry, SECCLASS_DIR);
3097 }
3098
3099 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3100 {
3101         return may_link(dir, dentry, MAY_RMDIR);
3102 }
3103
3104 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3105 {
3106         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3107 }
3108
3109 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3110                                 struct inode *new_inode, struct dentry *new_dentry)
3111 {
3112         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3113 }
3114
3115 static int selinux_inode_readlink(struct dentry *dentry)
3116 {
3117         const struct cred *cred = current_cred();
3118
3119         return dentry_has_perm(cred, dentry, FILE__READ);
3120 }
3121
3122 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3123                                      bool rcu)
3124 {
3125         const struct cred *cred = current_cred();
3126         struct common_audit_data ad;
3127         struct inode_security_struct *isec;
3128         u32 sid;
3129
3130         validate_creds(cred);
3131
3132         ad.type = LSM_AUDIT_DATA_DENTRY;
3133         ad.u.dentry = dentry;
3134         sid = cred_sid(cred);
3135         isec = inode_security_rcu(inode, rcu);
3136         if (IS_ERR(isec))
3137                 return PTR_ERR(isec);
3138
3139         return avc_has_perm_flags(&selinux_state,
3140                                   sid, isec->sid, isec->sclass, FILE__READ, &ad,
3141                                   rcu ? MAY_NOT_BLOCK : 0);
3142 }
3143
3144 static noinline int audit_inode_permission(struct inode *inode,
3145                                            u32 perms, u32 audited, u32 denied,
3146                                            int result,
3147                                            unsigned flags)
3148 {
3149         struct common_audit_data ad;
3150         struct inode_security_struct *isec = inode->i_security;
3151         int rc;
3152
3153         ad.type = LSM_AUDIT_DATA_INODE;
3154         ad.u.inode = inode;
3155
3156         rc = slow_avc_audit(&selinux_state,
3157                             current_sid(), isec->sid, isec->sclass, perms,
3158                             audited, denied, result, &ad, flags);
3159         if (rc)
3160                 return rc;
3161         return 0;
3162 }
3163
3164 static int selinux_inode_permission(struct inode *inode, int mask)
3165 {
3166         const struct cred *cred = current_cred();
3167         u32 perms;
3168         bool from_access;
3169         unsigned flags = mask & MAY_NOT_BLOCK;
3170         struct inode_security_struct *isec;
3171         u32 sid;
3172         struct av_decision avd;
3173         int rc, rc2;
3174         u32 audited, denied;
3175
3176         from_access = mask & MAY_ACCESS;
3177         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3178
3179         /* No permission to check.  Existence test. */
3180         if (!mask)
3181                 return 0;
3182
3183         validate_creds(cred);
3184
3185         if (unlikely(IS_PRIVATE(inode)))
3186                 return 0;
3187
3188         perms = file_mask_to_av(inode->i_mode, mask);
3189
3190         sid = cred_sid(cred);
3191         isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3192         if (IS_ERR(isec))
3193                 return PTR_ERR(isec);
3194
3195         rc = avc_has_perm_noaudit(&selinux_state,
3196                                   sid, isec->sid, isec->sclass, perms, 0, &avd);
3197         audited = avc_audit_required(perms, &avd, rc,
3198                                      from_access ? FILE__AUDIT_ACCESS : 0,
3199                                      &denied);
3200         if (likely(!audited))
3201                 return rc;
3202
3203         rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3204         if (rc2)
3205                 return rc2;
3206         return rc;
3207 }
3208
3209 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3210 {
3211         const struct cred *cred = current_cred();
3212         struct inode *inode = d_backing_inode(dentry);
3213         unsigned int ia_valid = iattr->ia_valid;
3214         __u32 av = FILE__WRITE;
3215
3216         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3217         if (ia_valid & ATTR_FORCE) {
3218                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3219                               ATTR_FORCE);
3220                 if (!ia_valid)
3221                         return 0;
3222         }
3223
3224         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3225                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3226                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3227
3228         if (selinux_policycap_openperm() &&
3229             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3230             (ia_valid & ATTR_SIZE) &&
3231             !(ia_valid & ATTR_FILE))
3232                 av |= FILE__OPEN;
3233
3234         return dentry_has_perm(cred, dentry, av);
3235 }
3236
3237 static int selinux_inode_getattr(const struct path *path)
3238 {
3239         return path_has_perm(current_cred(), path, FILE__GETATTR);
3240 }
3241
3242 static bool has_cap_mac_admin(bool audit)
3243 {
3244         const struct cred *cred = current_cred();
3245         int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT;
3246
3247         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit))
3248                 return false;
3249         if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true))
3250                 return false;
3251         return true;
3252 }
3253
3254 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3255                                   const void *value, size_t size, int flags)
3256 {
3257         struct inode *inode = d_backing_inode(dentry);
3258         struct inode_security_struct *isec;
3259         struct superblock_security_struct *sbsec;
3260         struct common_audit_data ad;
3261         u32 newsid, sid = current_sid();
3262         int rc = 0;
3263
3264         if (strcmp(name, XATTR_NAME_SELINUX)) {
3265                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3266                 if (rc)
3267                         return rc;
3268
3269                 /* Not an attribute we recognize, so just check the
3270                    ordinary setattr permission. */
3271                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3272         }
3273
3274         sbsec = inode->i_sb->s_security;
3275         if (!(sbsec->flags & SBLABEL_MNT))
3276                 return -EOPNOTSUPP;
3277
3278         if (!inode_owner_or_capable(inode))
3279                 return -EPERM;
3280
3281         ad.type = LSM_AUDIT_DATA_DENTRY;
3282         ad.u.dentry = dentry;
3283
3284         isec = backing_inode_security(dentry);
3285         rc = avc_has_perm(&selinux_state,
3286                           sid, isec->sid, isec->sclass,
3287                           FILE__RELABELFROM, &ad);
3288         if (rc)
3289                 return rc;
3290
3291         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3292                                      GFP_KERNEL);
3293         if (rc == -EINVAL) {
3294                 if (!has_cap_mac_admin(true)) {
3295                         struct audit_buffer *ab;
3296                         size_t audit_size;
3297
3298                         /* We strip a nul only if it is at the end, otherwise the
3299                          * context contains a nul and we should audit that */
3300                         if (value) {
3301                                 const char *str = value;
3302
3303                                 if (str[size - 1] == '\0')
3304                                         audit_size = size - 1;
3305                                 else
3306                                         audit_size = size;
3307                         } else {
3308                                 audit_size = 0;
3309                         }
3310                         ab = audit_log_start(audit_context(),
3311                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3312                         audit_log_format(ab, "op=setxattr invalid_context=");
3313                         audit_log_n_untrustedstring(ab, value, audit_size);
3314                         audit_log_end(ab);
3315
3316                         return rc;
3317                 }
3318                 rc = security_context_to_sid_force(&selinux_state, value,
3319                                                    size, &newsid);
3320         }
3321         if (rc)
3322                 return rc;
3323
3324         rc = avc_has_perm(&selinux_state,
3325                           sid, newsid, isec->sclass,
3326                           FILE__RELABELTO, &ad);
3327         if (rc)
3328                 return rc;
3329
3330         rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3331                                           sid, isec->sclass);
3332         if (rc)
3333                 return rc;
3334
3335         return avc_has_perm(&selinux_state,
3336                             newsid,
3337                             sbsec->sid,
3338                             SECCLASS_FILESYSTEM,
3339                             FILESYSTEM__ASSOCIATE,
3340                             &ad);
3341 }
3342
3343 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3344                                         const void *value, size_t size,
3345                                         int flags)
3346 {
3347         struct inode *inode = d_backing_inode(dentry);
3348         struct inode_security_struct *isec;
3349         u32 newsid;
3350         int rc;
3351
3352         if (strcmp(name, XATTR_NAME_SELINUX)) {
3353                 /* Not an attribute we recognize, so nothing to do. */
3354                 return;
3355         }
3356
3357         rc = security_context_to_sid_force(&selinux_state, value, size,
3358                                            &newsid);
3359         if (rc) {
3360                 printk(KERN_ERR "SELinux:  unable to map context to SID"
3361                        "for (%s, %lu), rc=%d\n",
3362                        inode->i_sb->s_id, inode->i_ino, -rc);
3363                 return;
3364         }
3365
3366         isec = backing_inode_security(dentry);
3367         spin_lock(&isec->lock);
3368         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3369         isec->sid = newsid;
3370         isec->initialized = LABEL_INITIALIZED;
3371         spin_unlock(&isec->lock);
3372
3373         return;
3374 }
3375
3376 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3377 {
3378         const struct cred *cred = current_cred();
3379
3380         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3381 }
3382
3383 static int selinux_inode_listxattr(struct dentry *dentry)
3384 {
3385         const struct cred *cred = current_cred();
3386
3387         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3388 }
3389
3390 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3391 {
3392         if (strcmp(name, XATTR_NAME_SELINUX)) {
3393                 int rc = cap_inode_removexattr(dentry, name);
3394                 if (rc)
3395                         return rc;
3396
3397                 /* Not an attribute we recognize, so just check the
3398                    ordinary setattr permission. */
3399                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3400         }
3401
3402         /* No one is allowed to remove a SELinux security label.
3403            You can change the label, but all data must be labeled. */
3404         return -EACCES;
3405 }
3406
3407 /*
3408  * Copy the inode security context value to the user.
3409  *
3410  * Permission check is handled by selinux_inode_getxattr hook.
3411  */
3412 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3413 {
3414         u32 size;
3415         int error;
3416         char *context = NULL;
3417         struct inode_security_struct *isec;
3418
3419         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3420                 return -EOPNOTSUPP;
3421
3422         /*
3423          * If the caller has CAP_MAC_ADMIN, then get the raw context
3424          * value even if it is not defined by current policy; otherwise,
3425          * use the in-core value under current policy.
3426          * Use the non-auditing forms of the permission checks since
3427          * getxattr may be called by unprivileged processes commonly
3428          * and lack of permission just means that we fall back to the
3429          * in-core context value, not a denial.
3430          */
3431         isec = inode_security(inode);
3432         if (has_cap_mac_admin(false))
3433                 error = security_sid_to_context_force(&selinux_state,
3434                                                       isec->sid, &context,
3435                                                       &size);
3436         else
3437                 error = security_sid_to_context(&selinux_state, isec->sid,
3438                                                 &context, &size);
3439         if (error)
3440                 return error;
3441         error = size;
3442         if (alloc) {
3443                 *buffer = context;
3444                 goto out_nofree;
3445         }
3446         kfree(context);
3447 out_nofree:
3448         return error;
3449 }
3450
3451 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3452                                      const void *value, size_t size, int flags)
3453 {
3454         struct inode_security_struct *isec = inode_security_novalidate(inode);
3455         u32 newsid;
3456         int rc;
3457
3458         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3459                 return -EOPNOTSUPP;
3460
3461         if (!value || !size)
3462                 return -EACCES;
3463
3464         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3465                                      GFP_KERNEL);
3466         if (rc)
3467                 return rc;
3468
3469         spin_lock(&isec->lock);
3470         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3471         isec->sid = newsid;
3472         isec->initialized = LABEL_INITIALIZED;
3473         spin_unlock(&isec->lock);
3474         return 0;
3475 }
3476
3477 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3478 {
3479         const int len = sizeof(XATTR_NAME_SELINUX);
3480         if (buffer && len <= buffer_size)
3481                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3482         return len;
3483 }
3484
3485 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3486 {
3487         struct inode_security_struct *isec = inode_security_novalidate(inode);
3488         *secid = isec->sid;
3489 }
3490
3491 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3492 {
3493         u32 sid;
3494         struct task_security_struct *tsec;
3495         struct cred *new_creds = *new;
3496
3497         if (new_creds == NULL) {
3498                 new_creds = prepare_creds();
3499                 if (!new_creds)
3500                         return -ENOMEM;
3501         }
3502
3503         tsec = new_creds->security;
3504         /* Get label from overlay inode and set it in create_sid */
3505         selinux_inode_getsecid(d_inode(src), &sid);
3506         tsec->create_sid = sid;
3507         *new = new_creds;
3508         return 0;
3509 }
3510
3511 static int selinux_inode_copy_up_xattr(const char *name)
3512 {
3513         /* The copy_up hook above sets the initial context on an inode, but we
3514          * don't then want to overwrite it by blindly copying all the lower
3515          * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3516          */
3517         if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3518                 return 1; /* Discard */
3519         /*
3520          * Any other attribute apart from SELINUX is not claimed, supported
3521          * by selinux.
3522          */
3523         return -EOPNOTSUPP;
3524 }
3525
3526 /* file security operations */
3527
3528 static int selinux_revalidate_file_permission(struct file *file, int mask)
3529 {
3530         const struct cred *cred = current_cred();
3531         struct inode *inode = file_inode(file);
3532
3533         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3534         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3535                 mask |= MAY_APPEND;
3536
3537         return file_has_perm(cred, file,
3538                              file_mask_to_av(inode->i_mode, mask));
3539 }
3540
3541 static int selinux_file_permission(struct file *file, int mask)
3542 {
3543         struct inode *inode = file_inode(file);
3544         struct file_security_struct *fsec = file->f_security;
3545         struct inode_security_struct *isec;
3546         u32 sid = current_sid();
3547
3548         if (!mask)
3549                 /* No permission to check.  Existence test. */
3550                 return 0;
3551
3552         isec = inode_security(inode);
3553         if (sid == fsec->sid && fsec->isid == isec->sid &&
3554             fsec->pseqno == avc_policy_seqno(&selinux_state))
3555                 /* No change since file_open check. */
3556                 return 0;
3557
3558         return selinux_revalidate_file_permission(file, mask);
3559 }
3560
3561 static int selinux_file_alloc_security(struct file *file)
3562 {
3563         return file_alloc_security(file);
3564 }
3565
3566 static void selinux_file_free_security(struct file *file)
3567 {
3568         file_free_security(file);
3569 }
3570
3571 /*
3572  * Check whether a task has the ioctl permission and cmd
3573  * operation to an inode.
3574  */
3575 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3576                 u32 requested, u16 cmd)
3577 {
3578         struct common_audit_data ad;
3579         struct file_security_struct *fsec = file->f_security;
3580         struct inode *inode = file_inode(file);
3581         struct inode_security_struct *isec;
3582         struct lsm_ioctlop_audit ioctl;
3583         u32 ssid = cred_sid(cred);
3584         int rc;
3585         u8 driver = cmd >> 8;
3586         u8 xperm = cmd & 0xff;
3587
3588         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3589         ad.u.op = &ioctl;
3590         ad.u.op->cmd = cmd;
3591         ad.u.op->path = file->f_path;
3592
3593         if (ssid != fsec->sid) {
3594                 rc = avc_has_perm(&selinux_state,
3595                                   ssid, fsec->sid,
3596                                 SECCLASS_FD,
3597                                 FD__USE,
3598                                 &ad);
3599                 if (rc)
3600                         goto out;
3601         }
3602
3603         if (unlikely(IS_PRIVATE(inode)))
3604                 return 0;
3605
3606         isec = inode_security(inode);
3607         rc = avc_has_extended_perms(&selinux_state,
3608                                     ssid, isec->sid, isec->sclass,
3609                                     requested, driver, xperm, &ad);
3610 out:
3611         return rc;
3612 }
3613
3614 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3615                               unsigned long arg)
3616 {
3617         const struct cred *cred = current_cred();
3618         int error = 0;
3619
3620         switch (cmd) {
3621         case FIONREAD:
3622         /* fall through */
3623         case FIBMAP:
3624         /* fall through */
3625         case FIGETBSZ:
3626         /* fall through */
3627         case FS_IOC_GETFLAGS:
3628         /* fall through */
3629         case FS_IOC_GETVERSION:
3630                 error = file_has_perm(cred, file, FILE__GETATTR);
3631                 break;
3632
3633         case FS_IOC_SETFLAGS:
3634         /* fall through */
3635         case FS_IOC_SETVERSION:
3636                 error = file_has_perm(cred, file, FILE__SETATTR);
3637                 break;
3638
3639         /* sys_ioctl() checks */
3640         case FIONBIO:
3641         /* fall through */
3642         case FIOASYNC:
3643                 error = file_has_perm(cred, file, 0);
3644                 break;
3645
3646         case KDSKBENT:
3647         case KDSKBSENT:
3648                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3649                                             SECURITY_CAP_AUDIT, true);
3650                 break;
3651
3652         /* default case assumes that the command will go
3653          * to the file's ioctl() function.
3654          */
3655         default:
3656                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3657         }
3658         return error;
3659 }
3660
3661 static int default_noexec;
3662
3663 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3664 {
3665         const struct cred *cred = current_cred();
3666         u32 sid = cred_sid(cred);
3667         int rc = 0;
3668
3669         if (default_noexec &&
3670             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3671                                    (!shared && (prot & PROT_WRITE)))) {
3672                 /*
3673                  * We are making executable an anonymous mapping or a
3674                  * private file mapping that will also be writable.
3675                  * This has an additional check.
3676                  */
3677                 rc = avc_has_perm(&selinux_state,
3678                                   sid, sid, SECCLASS_PROCESS,
3679                                   PROCESS__EXECMEM, NULL);
3680                 if (rc)
3681                         goto error;
3682         }
3683
3684         if (file) {
3685                 /* read access is always possible with a mapping */
3686                 u32 av = FILE__READ;
3687
3688                 /* write access only matters if the mapping is shared */
3689                 if (shared && (prot & PROT_WRITE))
3690                         av |= FILE__WRITE;
3691
3692                 if (prot & PROT_EXEC)
3693                         av |= FILE__EXECUTE;
3694
3695                 return file_has_perm(cred, file, av);
3696         }
3697
3698 error:
3699         return rc;
3700 }
3701
3702 static int selinux_mmap_addr(unsigned long addr)
3703 {
3704         int rc = 0;
3705
3706         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3707                 u32 sid = current_sid();
3708                 rc = avc_has_perm(&selinux_state,
3709                                   sid, sid, SECCLASS_MEMPROTECT,
3710                                   MEMPROTECT__MMAP_ZERO, NULL);
3711         }
3712
3713         return rc;
3714 }
3715
3716 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3717                              unsigned long prot, unsigned long flags)
3718 {
3719         struct common_audit_data ad;
3720         int rc;
3721
3722         if (file) {
3723                 ad.type = LSM_AUDIT_DATA_FILE;
3724                 ad.u.file = file;
3725                 rc = inode_has_perm(current_cred(), file_inode(file),
3726                                     FILE__MAP, &ad);
3727                 if (rc)
3728                         return rc;
3729         }
3730
3731         if (selinux_state.checkreqprot)
3732                 prot = reqprot;
3733
3734         return file_map_prot_check(file, prot,
3735                                    (flags & MAP_TYPE) == MAP_SHARED);
3736 }
3737
3738 static int selinux_file_mprotect(struct vm_area_struct *vma,
3739                                  unsigned long reqprot,
3740                                  unsigned long prot)
3741 {
3742         const struct cred *cred = current_cred();
3743         u32 sid = cred_sid(cred);
3744
3745         if (selinux_state.checkreqprot)
3746                 prot = reqprot;
3747
3748         if (default_noexec &&
3749             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3750                 int rc = 0;
3751                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3752                     vma->vm_end <= vma->vm_mm->brk) {
3753                         rc = avc_has_perm(&selinux_state,
3754                                           sid, sid, SECCLASS_PROCESS,
3755                                           PROCESS__EXECHEAP, NULL);
3756                 } else if (!vma->vm_file &&
3757                            ((vma->vm_start <= vma->vm_mm->start_stack &&
3758                              vma->vm_end >= vma->vm_mm->start_stack) ||
3759                             vma_is_stack_for_current(vma))) {
3760                         rc = avc_has_perm(&selinux_state,
3761                                           sid, sid, SECCLASS_PROCESS,
3762                                           PROCESS__EXECSTACK, NULL);
3763                 } else if (vma->vm_file && vma->anon_vma) {
3764                         /*
3765                          * We are making executable a file mapping that has
3766                          * had some COW done. Since pages might have been
3767                          * written, check ability to execute the possibly
3768                          * modified content.  This typically should only
3769                          * occur for text relocations.
3770                          */
3771                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3772                 }
3773                 if (rc)
3774                         return rc;
3775         }
3776
3777         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3778 }
3779
3780 static int selinux_file_lock(struct file *file, unsigned int cmd)
3781 {
3782         const struct cred *cred = current_cred();
3783
3784         return file_has_perm(cred, file, FILE__LOCK);
3785 }
3786
3787 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3788                               unsigned long arg)
3789 {
3790         const struct cred *cred = current_cred();
3791         int err = 0;
3792
3793         switch (cmd) {
3794         case F_SETFL:
3795                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3796                         err = file_has_perm(cred, file, FILE__WRITE);
3797                         break;
3798                 }
3799                 /* fall through */
3800         case F_SETOWN:
3801         case F_SETSIG:
3802         case F_GETFL:
3803         case F_GETOWN:
3804         case F_GETSIG:
3805         case F_GETOWNER_UIDS:
3806                 /* Just check FD__USE permission */
3807                 err = file_has_perm(cred, file, 0);
3808                 break;
3809         case F_GETLK:
3810         case F_SETLK:
3811         case F_SETLKW:
3812         case F_OFD_GETLK:
3813         case F_OFD_SETLK:
3814         case F_OFD_SETLKW:
3815 #if BITS_PER_LONG == 32
3816         case F_GETLK64:
3817         case F_SETLK64:
3818         case F_SETLKW64:
3819 #endif
3820                 err = file_has_perm(cred, file, FILE__LOCK);
3821                 break;
3822         }
3823
3824         return err;
3825 }
3826
3827 static void selinux_file_set_fowner(struct file *file)
3828 {
3829         struct file_security_struct *fsec;
3830
3831         fsec = file->f_security;
3832         fsec->fown_sid = current_sid();
3833 }
3834
3835 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3836                                        struct fown_struct *fown, int signum)
3837 {
3838         struct file *file;
3839         u32 sid = task_sid(tsk);
3840         u32 perm;
3841         struct file_security_struct *fsec;
3842
3843         /* struct fown_struct is never outside the context of a struct file */
3844         file = container_of(fown, struct file, f_owner);
3845
3846         fsec = file->f_security;
3847
3848         if (!signum)
3849                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3850         else
3851                 perm = signal_to_av(signum);
3852
3853         return avc_has_perm(&selinux_state,
3854                             fsec->fown_sid, sid,
3855                             SECCLASS_PROCESS, perm, NULL);
3856 }
3857
3858 static int selinux_file_receive(struct file *file)
3859 {
3860         const struct cred *cred = current_cred();
3861
3862         return file_has_perm(cred, file, file_to_av(file));
3863 }
3864
3865 static int selinux_file_open(struct file *file, const struct cred *cred)
3866 {
3867         struct file_security_struct *fsec;
3868         struct inode_security_struct *isec;
3869
3870         fsec = file->f_security;
3871         isec = inode_security(file_inode(file));
3872         /*
3873          * Save inode label and policy sequence number
3874          * at open-time so that selinux_file_permission
3875          * can determine whether revalidation is necessary.
3876          * Task label is already saved in the file security
3877          * struct as its SID.
3878          */
3879         fsec->isid = isec->sid;
3880         fsec->pseqno = avc_policy_seqno(&selinux_state);
3881         /*
3882          * Since the inode label or policy seqno may have changed
3883          * between the selinux_inode_permission check and the saving
3884          * of state above, recheck that access is still permitted.
3885          * Otherwise, access might never be revalidated against the
3886          * new inode label or new policy.
3887          * This check is not redundant - do not remove.
3888          */
3889         return file_path_has_perm(cred, file, open_file_to_av(file));
3890 }
3891
3892 /* task security operations */
3893
3894 static int selinux_task_alloc(struct task_struct *task,
3895                               unsigned long clone_flags)
3896 {
3897         u32 sid = current_sid();
3898
3899         return avc_has_perm(&selinux_state,
3900                             sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3901 }
3902
3903 /*
3904  * allocate the SELinux part of blank credentials
3905  */
3906 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3907 {
3908         struct task_security_struct *tsec;
3909
3910         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3911         if (!tsec)
3912                 return -ENOMEM;
3913
3914         cred->security = tsec;
3915         return 0;
3916 }
3917
3918 /*
3919  * detach and free the LSM part of a set of credentials
3920  */
3921 static void selinux_cred_free(struct cred *cred)
3922 {
3923         struct task_security_struct *tsec = cred->security;
3924
3925         /*
3926          * cred->security == NULL if security_cred_alloc_blank() or
3927          * security_prepare_creds() returned an error.
3928          */
3929         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3930         cred->security = (void *) 0x7UL;
3931         kfree(tsec);
3932 }
3933
3934 /*
3935  * prepare a new set of credentials for modification
3936  */
3937 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3938                                 gfp_t gfp)
3939 {
3940         const struct task_security_struct *old_tsec;
3941         struct task_security_struct *tsec;
3942
3943         old_tsec = old->security;
3944
3945         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3946         if (!tsec)
3947                 return -ENOMEM;
3948
3949         new->security = tsec;
3950         return 0;
3951 }
3952
3953 /*
3954  * transfer the SELinux data to a blank set of creds
3955  */
3956 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3957 {
3958         const struct task_security_struct *old_tsec = old->security;
3959         struct task_security_struct *tsec = new->security;
3960
3961         *tsec = *old_tsec;
3962 }
3963
3964 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3965 {
3966         *secid = cred_sid(c);
3967 }
3968
3969 /*
3970  * set the security data for a kernel service
3971  * - all the creation contexts are set to unlabelled
3972  */
3973 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3974 {
3975         struct task_security_struct *tsec = new->security;
3976         u32 sid = current_sid();
3977         int ret;
3978
3979         ret = avc_has_perm(&selinux_state,
3980                            sid, secid,
3981                            SECCLASS_KERNEL_SERVICE,
3982                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3983                            NULL);
3984         if (ret == 0) {
3985                 tsec->sid = secid;
3986                 tsec->create_sid = 0;
3987                 tsec->keycreate_sid = 0;
3988                 tsec->sockcreate_sid = 0;
3989         }
3990         return ret;
3991 }
3992
3993 /*
3994  * set the file creation context in a security record to the same as the
3995  * objective context of the specified inode
3996  */
3997 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3998 {
3999         struct inode_security_struct *isec = inode_security(inode);
4000         struct task_security_struct *tsec = new->security;
4001         u32 sid = current_sid();
4002         int ret;
4003
4004         ret = avc_has_perm(&selinux_state,
4005                            sid, isec->sid,
4006                            SECCLASS_KERNEL_SERVICE,
4007                            KERNEL_SERVICE__CREATE_FILES_AS,
4008                            NULL);
4009
4010         if (ret == 0)
4011                 tsec->create_sid = isec->sid;
4012         return ret;
4013 }
4014
4015 static int selinux_kernel_module_request(char *kmod_name)
4016 {
4017         struct common_audit_data ad;
4018
4019         ad.type = LSM_AUDIT_DATA_KMOD;
4020         ad.u.kmod_name = kmod_name;
4021
4022         return avc_has_perm(&selinux_state,
4023                             current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4024                             SYSTEM__MODULE_REQUEST, &ad);
4025 }
4026
4027 static int selinux_kernel_module_from_file(struct file *file)
4028 {
4029         struct common_audit_data ad;
4030         struct inode_security_struct *isec;
4031         struct file_security_struct *fsec;
4032         u32 sid = current_sid();
4033         int rc;
4034
4035         /* init_module */
4036         if (file == NULL)
4037                 return avc_has_perm(&selinux_state,
4038                                     sid, sid, SECCLASS_SYSTEM,
4039                                         SYSTEM__MODULE_LOAD, NULL);
4040
4041         /* finit_module */
4042
4043         ad.type = LSM_AUDIT_DATA_FILE;
4044         ad.u.file = file;
4045
4046         fsec = file->f_security;
4047         if (sid != fsec->sid) {
4048                 rc = avc_has_perm(&selinux_state,
4049                                   sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4050                 if (rc)
4051                         return rc;
4052         }
4053
4054         isec = inode_security(file_inode(file));
4055         return avc_has_perm(&selinux_state,
4056                             sid, isec->sid, SECCLASS_SYSTEM,
4057                                 SYSTEM__MODULE_LOAD, &ad);
4058 }
4059
4060 static int selinux_kernel_read_file(struct file *file,
4061                                     enum kernel_read_file_id id)
4062 {
4063         int rc = 0;
4064
4065         switch (id) {
4066         case READING_MODULE:
4067                 rc = selinux_kernel_module_from_file(file);
4068                 break;
4069         default:
4070                 break;
4071         }
4072
4073         return rc;
4074 }
4075
4076 static int selinux_kernel_load_data(enum kernel_load_data_id id)
4077 {
4078         int rc = 0;
4079
4080         switch (id) {
4081         case LOADING_MODULE:
4082                 rc = selinux_kernel_module_from_file(NULL);
4083         default:
4084                 break;
4085         }
4086
4087         return rc;
4088 }
4089
4090 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4091 {
4092         return avc_has_perm(&selinux_state,
4093                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4094                             PROCESS__SETPGID, NULL);
4095 }
4096
4097 static int selinux_task_getpgid(struct task_struct *p)
4098 {
4099         return avc_has_perm(&selinux_state,
4100                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4101                             PROCESS__GETPGID, NULL);
4102 }
4103
4104 static int selinux_task_getsid(struct task_struct *p)
4105 {
4106         return avc_has_perm(&selinux_state,
4107                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4108                             PROCESS__GETSESSION, NULL);
4109 }
4110
4111 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4112 {
4113         *secid = task_sid(p);
4114 }
4115
4116 static int selinux_task_setnice(struct task_struct *p, int nice)
4117 {
4118         return avc_has_perm(&selinux_state,
4119                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4120                             PROCESS__SETSCHED, NULL);
4121 }
4122
4123 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4124 {
4125         return avc_has_perm(&selinux_state,
4126                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4127                             PROCESS__SETSCHED, NULL);
4128 }
4129
4130 static int selinux_task_getioprio(struct task_struct *p)
4131 {
4132         return avc_has_perm(&selinux_state,
4133                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4134                             PROCESS__GETSCHED, NULL);
4135 }
4136
4137 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4138                                 unsigned int flags)
4139 {
4140         u32 av = 0;
4141
4142         if (!flags)
4143                 return 0;
4144         if (flags & LSM_PRLIMIT_WRITE)
4145                 av |= PROCESS__SETRLIMIT;
4146         if (flags & LSM_PRLIMIT_READ)
4147                 av |= PROCESS__GETRLIMIT;
4148         return avc_has_perm(&selinux_state,
4149                             cred_sid(cred), cred_sid(tcred),
4150                             SECCLASS_PROCESS, av, NULL);
4151 }
4152
4153 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4154                 struct rlimit *new_rlim)
4155 {
4156         struct rlimit *old_rlim = p->signal->rlim + resource;
4157
4158         /* Control the ability to change the hard limit (whether
4159            lowering or raising it), so that the hard limit can
4160            later be used as a safe reset point for the soft limit
4161            upon context transitions.  See selinux_bprm_committing_creds. */
4162         if (old_rlim->rlim_max != new_rlim->rlim_max)
4163                 return avc_has_perm(&selinux_state,
4164                                     current_sid(), task_sid(p),
4165                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4166
4167         return 0;
4168 }
4169
4170 static int selinux_task_setscheduler(struct task_struct *p)
4171 {
4172         return avc_has_perm(&selinux_state,
4173                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4174                             PROCESS__SETSCHED, NULL);
4175 }
4176
4177 static int selinux_task_getscheduler(struct task_struct *p)
4178 {
4179         return avc_has_perm(&selinux_state,
4180                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4181                             PROCESS__GETSCHED, NULL);
4182 }
4183
4184 static int selinux_task_movememory(struct task_struct *p)
4185 {
4186         return avc_has_perm(&selinux_state,
4187                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4188                             PROCESS__SETSCHED, NULL);
4189 }
4190
4191 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
4192                                 int sig, const struct cred *cred)
4193 {
4194         u32 secid;
4195         u32 perm;
4196
4197         if (!sig)
4198                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4199         else
4200                 perm = signal_to_av(sig);
4201         if (!cred)
4202                 secid = current_sid();
4203         else
4204                 secid = cred_sid(cred);
4205         return avc_has_perm(&selinux_state,
4206                             secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4207 }
4208
4209 static void selinux_task_to_inode(struct task_struct *p,
4210                                   struct inode *inode)
4211 {
4212         struct inode_security_struct *isec = inode->i_security;
4213         u32 sid = task_sid(p);
4214
4215         spin_lock(&isec->lock);
4216         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4217         isec->sid = sid;
4218         isec->initialized = LABEL_INITIALIZED;
4219         spin_unlock(&isec->lock);
4220 }
4221
4222 /* Returns error only if unable to parse addresses */
4223 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4224                         struct common_audit_data *ad, u8 *proto)
4225 {
4226         int offset, ihlen, ret = -EINVAL;
4227         struct iphdr _iph, *ih;
4228
4229         offset = skb_network_offset(skb);
4230         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4231         if (ih == NULL)
4232                 goto out;
4233
4234         ihlen = ih->ihl * 4;
4235         if (ihlen < sizeof(_iph))
4236                 goto out;
4237
4238         ad->u.net->v4info.saddr = ih->saddr;
4239         ad->u.net->v4info.daddr = ih->daddr;
4240         ret = 0;
4241
4242         if (proto)
4243                 *proto = ih->protocol;
4244
4245         switch (ih->protocol) {
4246         case IPPROTO_TCP: {
4247                 struct tcphdr _tcph, *th;
4248
4249                 if (ntohs(ih->frag_off) & IP_OFFSET)
4250                         break;
4251
4252                 offset += ihlen;
4253                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4254                 if (th == NULL)
4255                         break;
4256
4257                 ad->u.net->sport = th->source;
4258                 ad->u.net->dport = th->dest;
4259                 break;
4260         }
4261
4262         case IPPROTO_UDP: {
4263                 struct udphdr _udph, *uh;
4264
4265                 if (ntohs(ih->frag_off) & IP_OFFSET)
4266                         break;
4267
4268                 offset += ihlen;
4269                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4270                 if (uh == NULL)
4271                         break;
4272
4273                 ad->u.net->sport = uh->source;
4274                 ad->u.net->dport = uh->dest;
4275                 break;
4276         }
4277
4278         case IPPROTO_DCCP: {
4279                 struct dccp_hdr _dccph, *dh;
4280
4281                 if (ntohs(ih->frag_off) & IP_OFFSET)
4282                         break;
4283
4284                 offset += ihlen;
4285                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4286                 if (dh == NULL)
4287                         break;
4288
4289                 ad->u.net->sport = dh->dccph_sport;
4290                 ad->u.net->dport = dh->dccph_dport;
4291                 break;
4292         }
4293
4294 #if IS_ENABLED(CONFIG_IP_SCTP)
4295         case IPPROTO_SCTP: {
4296                 struct sctphdr _sctph, *sh;
4297
4298                 if (ntohs(ih->frag_off) & IP_OFFSET)
4299                         break;
4300
4301                 offset += ihlen;
4302                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4303                 if (sh == NULL)
4304                         break;
4305
4306                 ad->u.net->sport = sh->source;
4307                 ad->u.net->dport = sh->dest;
4308                 break;
4309         }
4310 #endif
4311         default:
4312                 break;
4313         }
4314 out:
4315         return ret;
4316 }
4317
4318 #if IS_ENABLED(CONFIG_IPV6)
4319
4320 /* Returns error only if unable to parse addresses */
4321 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4322                         struct common_audit_data *ad, u8 *proto)
4323 {
4324         u8 nexthdr;
4325         int ret = -EINVAL, offset;
4326         struct ipv6hdr _ipv6h, *ip6;
4327         __be16 frag_off;
4328
4329         offset = skb_network_offset(skb);
4330         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4331         if (ip6 == NULL)
4332                 goto out;
4333
4334         ad->u.net->v6info.saddr = ip6->saddr;
4335         ad->u.net->v6info.daddr = ip6->daddr;
4336         ret = 0;
4337
4338         nexthdr = ip6->nexthdr;
4339         offset += sizeof(_ipv6h);
4340         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4341         if (offset < 0)
4342                 goto out;
4343
4344         if (proto)
4345                 *proto = nexthdr;
4346
4347         switch (nexthdr) {
4348         case IPPROTO_TCP: {
4349                 struct tcphdr _tcph, *th;
4350
4351                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4352                 if (th == NULL)
4353                         break;
4354
4355                 ad->u.net->sport = th->source;
4356                 ad->u.net->dport = th->dest;
4357                 break;
4358         }
4359
4360         case IPPROTO_UDP: {
4361                 struct udphdr _udph, *uh;
4362
4363                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4364                 if (uh == NULL)
4365                         break;
4366
4367                 ad->u.net->sport = uh->source;
4368                 ad->u.net->dport = uh->dest;
4369                 break;
4370         }
4371
4372         case IPPROTO_DCCP: {
4373                 struct dccp_hdr _dccph, *dh;
4374
4375                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4376                 if (dh == NULL)
4377                         break;
4378
4379                 ad->u.net->sport = dh->dccph_sport;
4380                 ad->u.net->dport = dh->dccph_dport;
4381                 break;
4382         }
4383
4384 #if IS_ENABLED(CONFIG_IP_SCTP)
4385         case IPPROTO_SCTP: {
4386                 struct sctphdr _sctph, *sh;
4387
4388                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4389                 if (sh == NULL)
4390                         break;
4391
4392                 ad->u.net->sport = sh->source;
4393                 ad->u.net->dport = sh->dest;
4394                 break;
4395         }
4396 #endif
4397         /* includes fragments */
4398         default:
4399                 break;
4400         }
4401 out:
4402         return ret;
4403 }
4404
4405 #endif /* IPV6 */
4406
4407 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4408                              char **_addrp, int src, u8 *proto)
4409 {
4410         char *addrp;
4411         int ret;
4412
4413         switch (ad->u.net->family) {
4414         case PF_INET:
4415                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4416                 if (ret)
4417                         goto parse_error;
4418                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4419                                        &ad->u.net->v4info.daddr);
4420                 goto okay;
4421
4422 #if IS_ENABLED(CONFIG_IPV6)
4423         case PF_INET6:
4424                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4425                 if (ret)
4426                         goto parse_error;
4427                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4428                                        &ad->u.net->v6info.daddr);
4429                 goto okay;
4430 #endif  /* IPV6 */
4431         default:
4432                 addrp = NULL;
4433                 goto okay;
4434         }
4435
4436 parse_error:
4437         printk(KERN_WARNING
4438                "SELinux: failure in selinux_parse_skb(),"
4439                " unable to parse packet\n");
4440         return ret;
4441
4442 okay:
4443         if (_addrp)
4444                 *_addrp = addrp;
4445         return 0;
4446 }
4447
4448 /**
4449  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4450  * @skb: the packet
4451  * @family: protocol family
4452  * @sid: the packet's peer label SID
4453  *
4454  * Description:
4455  * Check the various different forms of network peer labeling and determine
4456  * the peer label/SID for the packet; most of the magic actually occurs in
4457  * the security server function security_net_peersid_cmp().  The function
4458  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4459  * or -EACCES if @sid is invalid due to inconsistencies with the different
4460  * peer labels.
4461  *
4462  */
4463 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4464 {
4465         int err;
4466         u32 xfrm_sid;
4467         u32 nlbl_sid;
4468         u32 nlbl_type;
4469
4470         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4471         if (unlikely(err))
4472                 return -EACCES;
4473         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4474         if (unlikely(err))
4475                 return -EACCES;
4476
4477         err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4478                                            nlbl_type, xfrm_sid, sid);
4479         if (unlikely(err)) {
4480                 printk(KERN_WARNING
4481                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4482                        " unable to determine packet's peer label\n");
4483                 return -EACCES;
4484         }
4485
4486         return 0;
4487 }
4488
4489 /**
4490  * selinux_conn_sid - Determine the child socket label for a connection
4491  * @sk_sid: the parent socket's SID
4492  * @skb_sid: the packet's SID
4493  * @conn_sid: the resulting connection SID
4494  *
4495  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4496  * combined with the MLS information from @skb_sid in order to create
4497  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4498  * of @sk_sid.  Returns zero on success, negative values on failure.
4499  *
4500  */
4501 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4502 {
4503         int err = 0;
4504
4505         if (skb_sid != SECSID_NULL)
4506                 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4507                                             conn_sid);
4508         else
4509                 *conn_sid = sk_sid;
4510
4511         return err;
4512 }
4513
4514 /* socket security operations */
4515
4516 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4517                                  u16 secclass, u32 *socksid)
4518 {
4519         if (tsec->sockcreate_sid > SECSID_NULL) {
4520                 *socksid = tsec->sockcreate_sid;
4521                 return 0;
4522         }
4523
4524         return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4525                                        secclass, NULL, socksid);
4526 }
4527
4528 static int sock_has_perm(struct sock *sk, u32 perms)
4529 {
4530         struct sk_security_struct *sksec = sk->sk_security;
4531         struct common_audit_data ad;
4532         struct lsm_network_audit net = {0,};
4533
4534         if (sksec->sid == SECINITSID_KERNEL)
4535                 return 0;
4536
4537         ad.type = LSM_AUDIT_DATA_NET;
4538         ad.u.net = &net;
4539         ad.u.net->sk = sk;
4540
4541         return avc_has_perm(&selinux_state,
4542                             current_sid(), sksec->sid, sksec->sclass, perms,
4543                             &ad);
4544 }
4545
4546 static int selinux_socket_create(int family, int type,
4547                                  int protocol, int kern)
4548 {
4549         const struct task_security_struct *tsec = current_security();
4550         u32 newsid;
4551         u16 secclass;
4552         int rc;
4553
4554         if (kern)
4555                 return 0;
4556
4557         secclass = socket_type_to_security_class(family, type, protocol);
4558         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4559         if (rc)
4560                 return rc;
4561
4562         return avc_has_perm(&selinux_state,
4563                             tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4564 }
4565
4566 static int selinux_socket_post_create(struct socket *sock, int family,
4567                                       int type, int protocol, int kern)
4568 {
4569         const struct task_security_struct *tsec = current_security();
4570         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4571         struct sk_security_struct *sksec;
4572         u16 sclass = socket_type_to_security_class(family, type, protocol);
4573         u32 sid = SECINITSID_KERNEL;
4574         int err = 0;
4575
4576         if (!kern) {
4577                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4578                 if (err)
4579                         return err;
4580         }
4581
4582         isec->sclass = sclass;
4583         isec->sid = sid;
4584         isec->initialized = LABEL_INITIALIZED;
4585
4586         if (sock->sk) {
4587                 sksec = sock->sk->sk_security;
4588                 sksec->sclass = sclass;
4589                 sksec->sid = sid;
4590                 /* Allows detection of the first association on this socket */
4591                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4592                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4593
4594                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4595         }
4596
4597         return err;
4598 }
4599
4600 static int selinux_socket_socketpair(struct socket *socka,
4601                                      struct socket *sockb)
4602 {
4603         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4604         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4605
4606         sksec_a->peer_sid = sksec_b->sid;
4607         sksec_b->peer_sid = sksec_a->sid;
4608
4609         return 0;
4610 }
4611
4612 /* Range of port numbers used to automatically bind.
4613    Need to determine whether we should perform a name_bind
4614    permission check between the socket and the port number. */
4615
4616 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4617 {
4618         struct sock *sk = sock->sk;
4619         struct sk_security_struct *sksec = sk->sk_security;
4620         u16 family;
4621         int err;
4622
4623         err = sock_has_perm(sk, SOCKET__BIND);
4624         if (err)
4625                 goto out;
4626
4627         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4628         family = sk->sk_family;
4629         if (family == PF_INET || family == PF_INET6) {
4630                 char *addrp;
4631                 struct common_audit_data ad;
4632                 struct lsm_network_audit net = {0,};
4633                 struct sockaddr_in *addr4 = NULL;
4634                 struct sockaddr_in6 *addr6 = NULL;
4635                 u16 family_sa = address->sa_family;
4636                 unsigned short snum;
4637                 u32 sid, node_perm;
4638
4639                 /*
4640                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4641                  * that validates multiple binding addresses. Because of this
4642                  * need to check address->sa_family as it is possible to have
4643                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4644                  */
4645                 switch (family_sa) {
4646                 case AF_UNSPEC:
4647                 case AF_INET:
4648                         if (addrlen < sizeof(struct sockaddr_in))
4649                                 return -EINVAL;
4650                         addr4 = (struct sockaddr_in *)address;
4651                         if (family_sa == AF_UNSPEC) {
4652                                 /* see __inet_bind(), we only want to allow
4653                                  * AF_UNSPEC if the address is INADDR_ANY
4654                                  */
4655                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4656                                         goto err_af;
4657                                 family_sa = AF_INET;
4658                         }
4659                         snum = ntohs(addr4->sin_port);
4660                         addrp = (char *)&addr4->sin_addr.s_addr;
4661                         break;
4662                 case AF_INET6:
4663                         if (addrlen < SIN6_LEN_RFC2133)
4664                                 return -EINVAL;
4665                         addr6 = (struct sockaddr_in6 *)address;
4666                         snum = ntohs(addr6->sin6_port);
4667                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4668                         break;
4669                 default:
4670                         goto err_af;
4671                 }
4672
4673                 ad.type = LSM_AUDIT_DATA_NET;
4674                 ad.u.net = &net;
4675                 ad.u.net->sport = htons(snum);
4676                 ad.u.net->family = family_sa;
4677
4678                 if (snum) {
4679                         int low, high;
4680
4681                         inet_get_local_port_range(sock_net(sk), &low, &high);
4682
4683                         if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
4684                             snum > high) {
4685                                 err = sel_netport_sid(sk->sk_protocol,
4686                                                       snum, &sid);
4687                                 if (err)
4688                                         goto out;
4689                                 err = avc_has_perm(&selinux_state,
4690                                                    sksec->sid, sid,
4691                                                    sksec->sclass,
4692                                                    SOCKET__NAME_BIND, &ad);
4693                                 if (err)
4694                                         goto out;
4695                         }
4696                 }
4697
4698                 switch (sksec->sclass) {
4699                 case SECCLASS_TCP_SOCKET:
4700                         node_perm = TCP_SOCKET__NODE_BIND;
4701                         break;
4702
4703                 case SECCLASS_UDP_SOCKET:
4704                         node_perm = UDP_SOCKET__NODE_BIND;
4705                         break;
4706
4707                 case SECCLASS_DCCP_SOCKET:
4708                         node_perm = DCCP_SOCKET__NODE_BIND;
4709                         break;
4710
4711                 case SECCLASS_SCTP_SOCKET:
4712                         node_perm = SCTP_SOCKET__NODE_BIND;
4713                         break;
4714
4715                 default:
4716                         node_perm = RAWIP_SOCKET__NODE_BIND;
4717                         break;
4718                 }
4719
4720                 err = sel_netnode_sid(addrp, family_sa, &sid);
4721                 if (err)
4722                         goto out;
4723
4724                 if (family_sa == AF_INET)
4725                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4726                 else
4727                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4728
4729                 err = avc_has_perm(&selinux_state,
4730                                    sksec->sid, sid,
4731                                    sksec->sclass, node_perm, &ad);
4732                 if (err)
4733                         goto out;
4734         }
4735 out:
4736         return err;
4737 err_af:
4738         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4739         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4740                 return -EINVAL;
4741         return -EAFNOSUPPORT;
4742 }
4743
4744 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4745  * and sctp_sendmsg(3) as described in Documentation/security/LSM-sctp.rst
4746  */
4747 static int selinux_socket_connect_helper(struct socket *sock,
4748                                          struct sockaddr *address, int addrlen)
4749 {
4750         struct sock *sk = sock->sk;
4751         struct sk_security_struct *sksec = sk->sk_security;
4752         int err;
4753
4754         err = sock_has_perm(sk, SOCKET__CONNECT);
4755         if (err)
4756                 return err;
4757
4758         /*
4759          * If a TCP, DCCP or SCTP socket, check name_connect permission
4760          * for the port.
4761          */
4762         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4763             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4764             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4765                 struct common_audit_data ad;
4766                 struct lsm_network_audit net = {0,};
4767                 struct sockaddr_in *addr4 = NULL;
4768                 struct sockaddr_in6 *addr6 = NULL;
4769                 unsigned short snum;
4770                 u32 sid, perm;
4771
4772                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4773                  * that validates multiple connect addresses. Because of this
4774                  * need to check address->sa_family as it is possible to have
4775                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4776                  */
4777                 switch (address->sa_family) {
4778                 case AF_INET:
4779                         addr4 = (struct sockaddr_in *)address;
4780                         if (addrlen < sizeof(struct sockaddr_in))
4781                                 return -EINVAL;
4782                         snum = ntohs(addr4->sin_port);
4783                         break;
4784                 case AF_INET6:
4785                         addr6 = (struct sockaddr_in6 *)address;
4786                         if (addrlen < SIN6_LEN_RFC2133)
4787                                 return -EINVAL;
4788                         snum = ntohs(addr6->sin6_port);
4789                         break;
4790                 default:
4791                         /* Note that SCTP services expect -EINVAL, whereas
4792                          * others expect -EAFNOSUPPORT.
4793                          */
4794                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4795                                 return -EINVAL;
4796                         else
4797                                 return -EAFNOSUPPORT;
4798                 }
4799
4800                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4801                 if (err)
4802                         return err;
4803
4804                 switch (sksec->sclass) {
4805                 case SECCLASS_TCP_SOCKET:
4806                         perm = TCP_SOCKET__NAME_CONNECT;
4807                         break;
4808                 case SECCLASS_DCCP_SOCKET:
4809                         perm = DCCP_SOCKET__NAME_CONNECT;
4810                         break;
4811                 case SECCLASS_SCTP_SOCKET:
4812                         perm = SCTP_SOCKET__NAME_CONNECT;
4813                         break;
4814                 }
4815
4816                 ad.type = LSM_AUDIT_DATA_NET;
4817                 ad.u.net = &net;
4818                 ad.u.net->dport = htons(snum);
4819                 ad.u.net->family = address->sa_family;
4820                 err = avc_has_perm(&selinux_state,
4821                                    sksec->sid, sid, sksec->sclass, perm, &ad);
4822                 if (err)
4823                         return err;
4824         }
4825
4826         return 0;
4827 }
4828
4829 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4830 static int selinux_socket_connect(struct socket *sock,
4831                                   struct sockaddr *address, int addrlen)
4832 {
4833         int err;
4834         struct sock *sk = sock->sk;
4835
4836         err = selinux_socket_connect_helper(sock, address, addrlen);
4837         if (err)
4838                 return err;
4839
4840         return selinux_netlbl_socket_connect(sk, address);
4841 }
4842
4843 static int selinux_socket_listen(struct socket *sock, int backlog)
4844 {
4845         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4846 }
4847
4848 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4849 {
4850         int err;
4851         struct inode_security_struct *isec;
4852         struct inode_security_struct *newisec;
4853         u16 sclass;
4854         u32 sid;
4855
4856         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4857         if (err)
4858                 return err;
4859
4860         isec = inode_security_novalidate(SOCK_INODE(sock));
4861         spin_lock(&isec->lock);
4862         sclass = isec->sclass;
4863         sid = isec->sid;
4864         spin_unlock(&isec->lock);
4865
4866         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4867         newisec->sclass = sclass;
4868         newisec->sid = sid;
4869         newisec->initialized = LABEL_INITIALIZED;
4870
4871         return 0;
4872 }
4873
4874 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4875                                   int size)
4876 {
4877         return sock_has_perm(sock->sk, SOCKET__WRITE);
4878 }
4879
4880 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4881                                   int size, int flags)
4882 {
4883         return sock_has_perm(sock->sk, SOCKET__READ);
4884 }
4885
4886 static int selinux_socket_getsockname(struct socket *sock)
4887 {
4888         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4889 }
4890
4891 static int selinux_socket_getpeername(struct socket *sock)
4892 {
4893         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4894 }
4895
4896 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4897 {
4898         int err;
4899
4900         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4901         if (err)
4902                 return err;
4903
4904         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4905 }
4906
4907 static int selinux_socket_getsockopt(struct socket *sock, int level,
4908                                      int optname)
4909 {
4910         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4911 }
4912
4913 static int selinux_socket_shutdown(struct socket *sock, int how)
4914 {
4915         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4916 }
4917
4918 static int selinux_socket_unix_stream_connect(struct sock *sock,
4919                                               struct sock *other,
4920                                               struct sock *newsk)
4921 {
4922         struct sk_security_struct *sksec_sock = sock->sk_security;
4923         struct sk_security_struct *sksec_other = other->sk_security;
4924         struct sk_security_struct *sksec_new = newsk->sk_security;
4925         struct common_audit_data ad;
4926         struct lsm_network_audit net = {0,};
4927         int err;
4928
4929         ad.type = LSM_AUDIT_DATA_NET;
4930         ad.u.net = &net;
4931         ad.u.net->sk = other;
4932
4933         err = avc_has_perm(&selinux_state,
4934                            sksec_sock->sid, sksec_other->sid,
4935                            sksec_other->sclass,
4936                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4937         if (err)
4938                 return err;
4939
4940         /* server child socket */
4941         sksec_new->peer_sid = sksec_sock->sid;
4942         err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4943                                     sksec_sock->sid, &sksec_new->sid);
4944         if (err)
4945                 return err;
4946
4947         /* connecting socket */
4948         sksec_sock->peer_sid = sksec_new->sid;
4949
4950         return 0;
4951 }
4952
4953 static int selinux_socket_unix_may_send(struct socket *sock,
4954                                         struct socket *other)
4955 {
4956         struct sk_security_struct *ssec = sock->sk->sk_security;
4957         struct sk_security_struct *osec = other->sk->sk_security;
4958         struct common_audit_data ad;
4959         struct lsm_network_audit net = {0,};
4960
4961         ad.type = LSM_AUDIT_DATA_NET;
4962         ad.u.net = &net;
4963         ad.u.net->sk = other->sk;
4964
4965         return avc_has_perm(&selinux_state,
4966                             ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4967                             &ad);
4968 }
4969
4970 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4971                                     char *addrp, u16 family, u32 peer_sid,
4972                                     struct common_audit_data *ad)
4973 {
4974         int err;
4975         u32 if_sid;
4976         u32 node_sid;
4977
4978         err = sel_netif_sid(ns, ifindex, &if_sid);
4979         if (err)
4980                 return err;
4981         err = avc_has_perm(&selinux_state,
4982                            peer_sid, if_sid,
4983                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4984         if (err)
4985                 return err;
4986
4987         err = sel_netnode_sid(addrp, family, &node_sid);
4988         if (err)
4989                 return err;
4990         return avc_has_perm(&selinux_state,
4991                             peer_sid, node_sid,
4992                             SECCLASS_NODE, NODE__RECVFROM, ad);
4993 }
4994
4995 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4996                                        u16 family)
4997 {
4998         int err = 0;
4999         struct sk_security_struct *sksec = sk->sk_security;
5000         u32 sk_sid = sksec->sid;
5001         struct common_audit_data ad;
5002         struct lsm_network_audit net = {0,};
5003         char *addrp;
5004
5005         ad.type = LSM_AUDIT_DATA_NET;
5006         ad.u.net = &net;
5007         ad.u.net->netif = skb->skb_iif;
5008         ad.u.net->family = family;
5009         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5010         if (err)
5011                 return err;
5012
5013         if (selinux_secmark_enabled()) {
5014                 err = avc_has_perm(&selinux_state,
5015                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5016                                    PACKET__RECV, &ad);
5017                 if (err)
5018                         return err;
5019         }
5020
5021         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5022         if (err)
5023                 return err;
5024         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5025
5026         return err;
5027 }
5028
5029 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5030 {
5031         int err;
5032         struct sk_security_struct *sksec = sk->sk_security;
5033         u16 family = sk->sk_family;
5034         u32 sk_sid = sksec->sid;
5035         struct common_audit_data ad;
5036         struct lsm_network_audit net = {0,};
5037         char *addrp;
5038         u8 secmark_active;
5039         u8 peerlbl_active;
5040
5041         if (family != PF_INET && family != PF_INET6)
5042                 return 0;
5043
5044         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5045         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5046                 family = PF_INET;
5047
5048         /* If any sort of compatibility mode is enabled then handoff processing
5049          * to the selinux_sock_rcv_skb_compat() function to deal with the
5050          * special handling.  We do this in an attempt to keep this function
5051          * as fast and as clean as possible. */
5052         if (!selinux_policycap_netpeer())
5053                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5054
5055         secmark_active = selinux_secmark_enabled();
5056         peerlbl_active = selinux_peerlbl_enabled();
5057         if (!secmark_active && !peerlbl_active)
5058                 return 0;
5059
5060         ad.type = LSM_AUDIT_DATA_NET;
5061         ad.u.net = &net;
5062         ad.u.net->netif = skb->skb_iif;
5063         ad.u.net->family = family;
5064         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5065         if (err)
5066                 return err;
5067
5068         if (peerlbl_active) {
5069                 u32 peer_sid;
5070
5071                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5072                 if (err)
5073                         return err;
5074                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5075                                                addrp, family, peer_sid, &ad);
5076                 if (err) {
5077                         selinux_netlbl_err(skb, family, err, 0);
5078                         return err;
5079                 }
5080                 err = avc_has_perm(&selinux_state,
5081                                    sk_sid, peer_sid, SECCLASS_PEER,
5082                                    PEER__RECV, &ad);
5083                 if (err) {
5084                         selinux_netlbl_err(skb, family, err, 0);
5085                         return err;
5086                 }
5087         }
5088
5089         if (secmark_active) {
5090                 err = avc_has_perm(&selinux_state,
5091                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5092                                    PACKET__RECV, &ad);
5093                 if (err)
5094                         return err;
5095         }
5096
5097         return err;
5098 }
5099
5100 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5101                                             int __user *optlen, unsigned len)
5102 {
5103         int err = 0;
5104         char *scontext;
5105         u32 scontext_len;
5106         struct sk_security_struct *sksec = sock->sk->sk_security;
5107         u32 peer_sid = SECSID_NULL;
5108
5109         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5110             sksec->sclass == SECCLASS_TCP_SOCKET ||
5111             sksec->sclass == SECCLASS_SCTP_SOCKET)
5112                 peer_sid = sksec->peer_sid;
5113         if (peer_sid == SECSID_NULL)
5114                 return -ENOPROTOOPT;
5115
5116         err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5117                                       &scontext_len);
5118         if (err)
5119                 return err;
5120
5121         if (scontext_len > len) {
5122                 err = -ERANGE;
5123                 goto out_len;
5124         }
5125
5126         if (copy_to_user(optval, scontext, scontext_len))
5127                 err = -EFAULT;
5128
5129 out_len:
5130         if (put_user(scontext_len, optlen))
5131                 err = -EFAULT;
5132         kfree(scontext);
5133         return err;
5134 }
5135
5136 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5137 {
5138         u32 peer_secid = SECSID_NULL;
5139         u16 family;
5140         struct inode_security_struct *isec;
5141
5142         if (skb && skb->protocol == htons(ETH_P_IP))
5143                 family = PF_INET;
5144         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5145                 family = PF_INET6;
5146         else if (sock)
5147                 family = sock->sk->sk_family;
5148         else
5149                 goto out;
5150
5151         if (sock && family == PF_UNIX) {
5152                 isec = inode_security_novalidate(SOCK_INODE(sock));
5153                 peer_secid = isec->sid;
5154         } else if (skb)
5155                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5156
5157 out:
5158         *secid = peer_secid;
5159         if (peer_secid == SECSID_NULL)
5160                 return -EINVAL;
5161         return 0;
5162 }
5163
5164 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5165 {
5166         struct sk_security_struct *sksec;
5167
5168         sksec = kzalloc(sizeof(*sksec), priority);
5169         if (!sksec)
5170                 return -ENOMEM;
5171
5172         sksec->peer_sid = SECINITSID_UNLABELED;
5173         sksec->sid = SECINITSID_UNLABELED;
5174         sksec->sclass = SECCLASS_SOCKET;
5175         selinux_netlbl_sk_security_reset(sksec);
5176         sk->sk_security = sksec;
5177
5178         return 0;
5179 }
5180
5181 static void selinux_sk_free_security(struct sock *sk)
5182 {
5183         struct sk_security_struct *sksec = sk->sk_security;
5184
5185         sk->sk_security = NULL;
5186         selinux_netlbl_sk_security_free(sksec);
5187         kfree(sksec);
5188 }
5189
5190 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5191 {
5192         struct sk_security_struct *sksec = sk->sk_security;
5193         struct sk_security_struct *newsksec = newsk->sk_security;
5194
5195         newsksec->sid = sksec->sid;
5196         newsksec->peer_sid = sksec->peer_sid;
5197         newsksec->sclass = sksec->sclass;
5198
5199         selinux_netlbl_sk_security_reset(newsksec);
5200 }
5201
5202 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5203 {
5204         if (!sk)
5205                 *secid = SECINITSID_ANY_SOCKET;
5206         else {
5207                 struct sk_security_struct *sksec = sk->sk_security;
5208
5209                 *secid = sksec->sid;
5210         }
5211 }
5212
5213 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5214 {
5215         struct inode_security_struct *isec =
5216                 inode_security_novalidate(SOCK_INODE(parent));
5217         struct sk_security_struct *sksec = sk->sk_security;
5218
5219         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5220             sk->sk_family == PF_UNIX)
5221                 isec->sid = sksec->sid;
5222         sksec->sclass = isec->sclass;
5223 }
5224
5225 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5226  * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5227  * already present).
5228  */
5229 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5230                                       struct sk_buff *skb)
5231 {
5232         struct sk_security_struct *sksec = ep->base.sk->sk_security;
5233         struct common_audit_data ad;
5234         struct lsm_network_audit net = {0,};
5235         u8 peerlbl_active;
5236         u32 peer_sid = SECINITSID_UNLABELED;
5237         u32 conn_sid;
5238         int err = 0;
5239
5240         if (!selinux_policycap_extsockclass())
5241                 return 0;
5242
5243         peerlbl_active = selinux_peerlbl_enabled();
5244
5245         if (peerlbl_active) {
5246                 /* This will return peer_sid = SECSID_NULL if there are
5247                  * no peer labels, see security_net_peersid_resolve().
5248                  */
5249                 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5250                                               &peer_sid);
5251                 if (err)
5252                         return err;
5253
5254                 if (peer_sid == SECSID_NULL)
5255                         peer_sid = SECINITSID_UNLABELED;
5256         }
5257
5258         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5259                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5260
5261                 /* Here as first association on socket. As the peer SID
5262                  * was allowed by peer recv (and the netif/node checks),
5263                  * then it is approved by policy and used as the primary
5264                  * peer SID for getpeercon(3).
5265                  */
5266                 sksec->peer_sid = peer_sid;
5267         } else if  (sksec->peer_sid != peer_sid) {
5268                 /* Other association peer SIDs are checked to enforce
5269                  * consistency among the peer SIDs.
5270                  */
5271                 ad.type = LSM_AUDIT_DATA_NET;
5272                 ad.u.net = &net;
5273                 ad.u.net->sk = ep->base.sk;
5274                 err = avc_has_perm(&selinux_state,
5275                                    sksec->peer_sid, peer_sid, sksec->sclass,
5276                                    SCTP_SOCKET__ASSOCIATION, &ad);
5277                 if (err)
5278                         return err;
5279         }
5280
5281         /* Compute the MLS component for the connection and store
5282          * the information in ep. This will be used by SCTP TCP type
5283          * sockets and peeled off connections as they cause a new
5284          * socket to be generated. selinux_sctp_sk_clone() will then
5285          * plug this into the new socket.
5286          */
5287         err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5288         if (err)
5289                 return err;
5290
5291         ep->secid = conn_sid;
5292         ep->peer_secid = peer_sid;
5293
5294         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5295         return selinux_netlbl_sctp_assoc_request(ep, skb);
5296 }
5297
5298 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5299  * based on their @optname.
5300  */
5301 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5302                                      struct sockaddr *address,
5303                                      int addrlen)
5304 {
5305         int len, err = 0, walk_size = 0;
5306         void *addr_buf;
5307         struct sockaddr *addr;
5308         struct socket *sock;
5309
5310         if (!selinux_policycap_extsockclass())
5311                 return 0;
5312
5313         /* Process one or more addresses that may be IPv4 or IPv6 */
5314         sock = sk->sk_socket;
5315         addr_buf = address;
5316
5317         while (walk_size < addrlen) {
5318                 addr = addr_buf;
5319                 switch (addr->sa_family) {
5320                 case AF_UNSPEC:
5321                 case AF_INET:
5322                         len = sizeof(struct sockaddr_in);
5323                         break;
5324                 case AF_INET6:
5325                         len = sizeof(struct sockaddr_in6);
5326                         break;
5327                 default:
5328                         return -EINVAL;
5329                 }
5330
5331                 err = -EINVAL;
5332                 switch (optname) {
5333                 /* Bind checks */
5334                 case SCTP_PRIMARY_ADDR:
5335                 case SCTP_SET_PEER_PRIMARY_ADDR:
5336                 case SCTP_SOCKOPT_BINDX_ADD:
5337                         err = selinux_socket_bind(sock, addr, len);
5338                         break;
5339                 /* Connect checks */
5340                 case SCTP_SOCKOPT_CONNECTX:
5341                 case SCTP_PARAM_SET_PRIMARY:
5342                 case SCTP_PARAM_ADD_IP:
5343                 case SCTP_SENDMSG_CONNECT:
5344                         err = selinux_socket_connect_helper(sock, addr, len);
5345                         if (err)
5346                                 return err;
5347
5348                         /* As selinux_sctp_bind_connect() is called by the
5349                          * SCTP protocol layer, the socket is already locked,
5350                          * therefore selinux_netlbl_socket_connect_locked() is
5351                          * is called here. The situations handled are:
5352                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5353                          * whenever a new IP address is added or when a new
5354                          * primary address is selected.
5355                          * Note that an SCTP connect(2) call happens before
5356                          * the SCTP protocol layer and is handled via
5357                          * selinux_socket_connect().
5358                          */
5359                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5360                         break;
5361                 }
5362
5363                 if (err)
5364                         return err;
5365
5366                 addr_buf += len;
5367                 walk_size += len;
5368         }
5369
5370         return 0;
5371 }
5372
5373 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5374 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5375                                   struct sock *newsk)
5376 {
5377         struct sk_security_struct *sksec = sk->sk_security;
5378         struct sk_security_struct *newsksec = newsk->sk_security;
5379
5380         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5381          * the non-sctp clone version.
5382          */
5383         if (!selinux_policycap_extsockclass())
5384                 return selinux_sk_clone_security(sk, newsk);
5385
5386         newsksec->sid = ep->secid;
5387         newsksec->peer_sid = ep->peer_secid;
5388         newsksec->sclass = sksec->sclass;
5389         selinux_netlbl_sctp_sk_clone(sk, newsk);
5390 }
5391
5392 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5393                                      struct request_sock *req)
5394 {
5395         struct sk_security_struct *sksec = sk->sk_security;
5396         int err;
5397         u16 family = req->rsk_ops->family;
5398         u32 connsid;
5399         u32 peersid;
5400
5401         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5402         if (err)
5403                 return err;
5404         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5405         if (err)
5406                 return err;
5407         req->secid = connsid;
5408         req->peer_secid = peersid;
5409
5410         return selinux_netlbl_inet_conn_request(req, family);
5411 }
5412
5413 static void selinux_inet_csk_clone(struct sock *newsk,
5414                                    const struct request_sock *req)
5415 {
5416         struct sk_security_struct *newsksec = newsk->sk_security;
5417
5418         newsksec->sid = req->secid;
5419         newsksec->peer_sid = req->peer_secid;
5420         /* NOTE: Ideally, we should also get the isec->sid for the
5421            new socket in sync, but we don't have the isec available yet.
5422            So we will wait until sock_graft to do it, by which
5423            time it will have been created and available. */
5424
5425         /* We don't need to take any sort of lock here as we are the only
5426          * thread with access to newsksec */
5427         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5428 }
5429
5430 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5431 {
5432         u16 family = sk->sk_family;
5433         struct sk_security_struct *sksec = sk->sk_security;
5434
5435         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5436         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5437                 family = PF_INET;
5438
5439         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5440 }
5441
5442 static int selinux_secmark_relabel_packet(u32 sid)
5443 {
5444         const struct task_security_struct *__tsec;
5445         u32 tsid;
5446
5447         __tsec = current_security();
5448         tsid = __tsec->sid;
5449
5450         return avc_has_perm(&selinux_state,
5451                             tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5452                             NULL);
5453 }
5454
5455 static void selinux_secmark_refcount_inc(void)
5456 {
5457         atomic_inc(&selinux_secmark_refcount);
5458 }
5459
5460 static void selinux_secmark_refcount_dec(void)
5461 {
5462         atomic_dec(&selinux_secmark_refcount);
5463 }
5464
5465 static void selinux_req_classify_flow(const struct request_sock *req,
5466                                       struct flowi *fl)
5467 {
5468         fl->flowi_secid = req->secid;
5469 }
5470
5471 static int selinux_tun_dev_alloc_security(void **security)
5472 {
5473         struct tun_security_struct *tunsec;
5474
5475         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5476         if (!tunsec)
5477                 return -ENOMEM;
5478         tunsec->sid = current_sid();
5479
5480         *security = tunsec;
5481         return 0;
5482 }
5483
5484 static void selinux_tun_dev_free_security(void *security)
5485 {
5486         kfree(security);
5487 }
5488
5489 static int selinux_tun_dev_create(void)
5490 {
5491         u32 sid = current_sid();
5492
5493         /* we aren't taking into account the "sockcreate" SID since the socket
5494          * that is being created here is not a socket in the traditional sense,
5495          * instead it is a private sock, accessible only to the kernel, and
5496          * representing a wide range of network traffic spanning multiple
5497          * connections unlike traditional sockets - check the TUN driver to
5498          * get a better understanding of why this socket is special */
5499
5500         return avc_has_perm(&selinux_state,
5501                             sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5502                             NULL);
5503 }
5504
5505 static int selinux_tun_dev_attach_queue(void *security)
5506 {
5507         struct tun_security_struct *tunsec = security;
5508
5509         return avc_has_perm(&selinux_state,
5510                             current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5511                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5512 }
5513
5514 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5515 {
5516         struct tun_security_struct *tunsec = security;
5517         struct sk_security_struct *sksec = sk->sk_security;
5518
5519         /* we don't currently perform any NetLabel based labeling here and it
5520          * isn't clear that we would want to do so anyway; while we could apply
5521          * labeling without the support of the TUN user the resulting labeled
5522          * traffic from the other end of the connection would almost certainly
5523          * cause confusion to the TUN user that had no idea network labeling
5524          * protocols were being used */
5525
5526         sksec->sid = tunsec->sid;
5527         sksec->sclass = SECCLASS_TUN_SOCKET;
5528
5529         return 0;
5530 }
5531
5532 static int selinux_tun_dev_open(void *security)
5533 {
5534         struct tun_security_struct *tunsec = security;
5535         u32 sid = current_sid();
5536         int err;
5537
5538         err = avc_has_perm(&selinux_state,
5539                            sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5540                            TUN_SOCKET__RELABELFROM, NULL);
5541         if (err)
5542                 return err;
5543         err = avc_has_perm(&selinux_state,
5544                            sid, sid, SECCLASS_TUN_SOCKET,
5545                            TUN_SOCKET__RELABELTO, NULL);
5546         if (err)
5547                 return err;
5548         tunsec->sid = sid;
5549
5550         return 0;
5551 }
5552
5553 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5554 {
5555         int err = 0;
5556         u32 perm;
5557         struct nlmsghdr *nlh;
5558         struct sk_security_struct *sksec = sk->sk_security;
5559
5560         if (skb->len < NLMSG_HDRLEN) {
5561                 err = -EINVAL;
5562                 goto out;
5563         }
5564         nlh = nlmsg_hdr(skb);
5565
5566         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5567         if (err) {
5568                 if (err == -EINVAL) {
5569                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5570                                " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5571                                " pig=%d comm=%s\n",
5572                                sk->sk_protocol, nlh->nlmsg_type,
5573                                secclass_map[sksec->sclass - 1].name,
5574                                task_pid_nr(current), current->comm);
5575                         if (!enforcing_enabled(&selinux_state) ||
5576                             security_get_allow_unknown(&selinux_state))
5577                                 err = 0;
5578                 }
5579
5580                 /* Ignore */
5581                 if (err == -ENOENT)
5582                         err = 0;
5583                 goto out;
5584         }
5585
5586         err = sock_has_perm(sk, perm);
5587 out:
5588         return err;
5589 }
5590
5591 #ifdef CONFIG_NETFILTER
5592
5593 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5594                                        const struct net_device *indev,
5595                                        u16 family)
5596 {
5597         int err;
5598         char *addrp;
5599         u32 peer_sid;
5600         struct common_audit_data ad;
5601         struct lsm_network_audit net = {0,};
5602         u8 secmark_active;
5603         u8 netlbl_active;
5604         u8 peerlbl_active;
5605
5606         if (!selinux_policycap_netpeer())
5607                 return NF_ACCEPT;
5608
5609         secmark_active = selinux_secmark_enabled();
5610         netlbl_active = netlbl_enabled();
5611         peerlbl_active = selinux_peerlbl_enabled();
5612         if (!secmark_active && !peerlbl_active)
5613                 return NF_ACCEPT;
5614
5615         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5616                 return NF_DROP;
5617
5618         ad.type = LSM_AUDIT_DATA_NET;
5619         ad.u.net = &net;
5620         ad.u.net->netif = indev->ifindex;
5621         ad.u.net->family = family;
5622         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5623                 return NF_DROP;
5624
5625         if (peerlbl_active) {
5626                 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5627                                                addrp, family, peer_sid, &ad);
5628                 if (err) {
5629                         selinux_netlbl_err(skb, family, err, 1);
5630                         return NF_DROP;
5631                 }
5632         }
5633
5634         if (secmark_active)
5635                 if (avc_has_perm(&selinux_state,
5636                                  peer_sid, skb->secmark,
5637                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5638                         return NF_DROP;
5639
5640         if (netlbl_active)
5641                 /* we do this in the FORWARD path and not the POST_ROUTING
5642                  * path because we want to make sure we apply the necessary
5643                  * labeling before IPsec is applied so we can leverage AH
5644                  * protection */
5645                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5646                         return NF_DROP;
5647
5648         return NF_ACCEPT;
5649 }
5650
5651 static unsigned int selinux_ipv4_forward(void *priv,
5652                                          struct sk_buff *skb,
5653                                          const struct nf_hook_state *state)
5654 {
5655         return selinux_ip_forward(skb, state->in, PF_INET);
5656 }
5657
5658 #if IS_ENABLED(CONFIG_IPV6)
5659 static unsigned int selinux_ipv6_forward(void *priv,
5660                                          struct sk_buff *skb,
5661                                          const struct nf_hook_state *state)
5662 {
5663         return selinux_ip_forward(skb, state->in, PF_INET6);
5664 }
5665 #endif  /* IPV6 */
5666
5667 static unsigned int selinux_ip_output(struct sk_buff *skb,
5668                                       u16 family)
5669 {
5670         struct sock *sk;
5671         u32 sid;
5672
5673         if (!netlbl_enabled())
5674                 return NF_ACCEPT;
5675
5676         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5677          * because we want to make sure we apply the necessary labeling
5678          * before IPsec is applied so we can leverage AH protection */
5679         sk = skb->sk;
5680         if (sk) {
5681                 struct sk_security_struct *sksec;
5682
5683                 if (sk_listener(sk))
5684                         /* if the socket is the listening state then this
5685                          * packet is a SYN-ACK packet which means it needs to
5686                          * be labeled based on the connection/request_sock and
5687                          * not the parent socket.  unfortunately, we can't
5688                          * lookup the request_sock yet as it isn't queued on
5689                          * the parent socket until after the SYN-ACK is sent.
5690                          * the "solution" is to simply pass the packet as-is
5691                          * as any IP option based labeling should be copied
5692                          * from the initial connection request (in the IP
5693                          * layer).  it is far from ideal, but until we get a
5694                          * security label in the packet itself this is the
5695                          * best we can do. */
5696                         return NF_ACCEPT;
5697
5698                 /* standard practice, label using the parent socket */
5699                 sksec = sk->sk_security;
5700                 sid = sksec->sid;
5701         } else
5702                 sid = SECINITSID_KERNEL;
5703         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5704                 return NF_DROP;
5705
5706         return NF_ACCEPT;
5707 }
5708
5709 static unsigned int selinux_ipv4_output(void *priv,
5710                                         struct sk_buff *skb,
5711                                         const struct nf_hook_state *state)
5712 {
5713         return selinux_ip_output(skb, PF_INET);
5714 }
5715
5716 #if IS_ENABLED(CONFIG_IPV6)
5717 static unsigned int selinux_ipv6_output(void *priv,
5718                                         struct sk_buff *skb,
5719                                         const struct nf_hook_state *state)
5720 {
5721         return selinux_ip_output(skb, PF_INET6);
5722 }
5723 #endif  /* IPV6 */
5724
5725 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5726                                                 int ifindex,
5727                                                 u16 family)
5728 {
5729         struct sock *sk = skb_to_full_sk(skb);
5730         struct sk_security_struct *sksec;
5731         struct common_audit_data ad;
5732         struct lsm_network_audit net = {0,};
5733         char *addrp;
5734         u8 proto;
5735
5736         if (sk == NULL)
5737                 return NF_ACCEPT;
5738         sksec = sk->sk_security;
5739
5740         ad.type = LSM_AUDIT_DATA_NET;
5741         ad.u.net = &net;
5742         ad.u.net->netif = ifindex;
5743         ad.u.net->family = family;
5744         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5745                 return NF_DROP;
5746
5747         if (selinux_secmark_enabled())
5748                 if (avc_has_perm(&selinux_state,
5749                                  sksec->sid, skb->secmark,
5750                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5751                         return NF_DROP_ERR(-ECONNREFUSED);
5752
5753         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5754                 return NF_DROP_ERR(-ECONNREFUSED);
5755
5756         return NF_ACCEPT;
5757 }
5758
5759 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5760                                          const struct net_device *outdev,
5761                                          u16 family)
5762 {
5763         u32 secmark_perm;
5764         u32 peer_sid;
5765         int ifindex = outdev->ifindex;
5766         struct sock *sk;
5767         struct common_audit_data ad;
5768         struct lsm_network_audit net = {0,};
5769         char *addrp;
5770         u8 secmark_active;
5771         u8 peerlbl_active;
5772
5773         /* If any sort of compatibility mode is enabled then handoff processing
5774          * to the selinux_ip_postroute_compat() function to deal with the
5775          * special handling.  We do this in an attempt to keep this function
5776          * as fast and as clean as possible. */
5777         if (!selinux_policycap_netpeer())
5778                 return selinux_ip_postroute_compat(skb, ifindex, family);
5779
5780         secmark_active = selinux_secmark_enabled();
5781         peerlbl_active = selinux_peerlbl_enabled();
5782         if (!secmark_active && !peerlbl_active)
5783                 return NF_ACCEPT;
5784
5785         sk = skb_to_full_sk(skb);
5786
5787 #ifdef CONFIG_XFRM
5788         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5789          * packet transformation so allow the packet to pass without any checks
5790          * since we'll have another chance to perform access control checks
5791          * when the packet is on it's final way out.
5792          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5793          *       is NULL, in this case go ahead and apply access control.
5794          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5795          *       TCP listening state we cannot wait until the XFRM processing
5796          *       is done as we will miss out on the SA label if we do;
5797          *       unfortunately, this means more work, but it is only once per
5798          *       connection. */
5799         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5800             !(sk && sk_listener(sk)))
5801                 return NF_ACCEPT;
5802 #endif
5803
5804         if (sk == NULL) {
5805                 /* Without an associated socket the packet is either coming
5806                  * from the kernel or it is being forwarded; check the packet
5807                  * to determine which and if the packet is being forwarded
5808                  * query the packet directly to determine the security label. */
5809                 if (skb->skb_iif) {
5810                         secmark_perm = PACKET__FORWARD_OUT;
5811                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5812                                 return NF_DROP;
5813                 } else {
5814                         secmark_perm = PACKET__SEND;
5815                         peer_sid = SECINITSID_KERNEL;
5816                 }
5817         } else if (sk_listener(sk)) {
5818                 /* Locally generated packet but the associated socket is in the
5819                  * listening state which means this is a SYN-ACK packet.  In
5820                  * this particular case the correct security label is assigned
5821                  * to the connection/request_sock but unfortunately we can't
5822                  * query the request_sock as it isn't queued on the parent
5823                  * socket until after the SYN-ACK packet is sent; the only
5824                  * viable choice is to regenerate the label like we do in
5825                  * selinux_inet_conn_request().  See also selinux_ip_output()
5826                  * for similar problems. */
5827                 u32 skb_sid;
5828                 struct sk_security_struct *sksec;
5829
5830                 sksec = sk->sk_security;
5831                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5832                         return NF_DROP;
5833                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5834                  * and the packet has been through at least one XFRM
5835                  * transformation then we must be dealing with the "final"
5836                  * form of labeled IPsec packet; since we've already applied
5837                  * all of our access controls on this packet we can safely
5838                  * pass the packet. */
5839                 if (skb_sid == SECSID_NULL) {
5840                         switch (family) {
5841                         case PF_INET:
5842                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5843                                         return NF_ACCEPT;
5844                                 break;
5845                         case PF_INET6:
5846                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5847                                         return NF_ACCEPT;
5848                                 break;
5849                         default:
5850                                 return NF_DROP_ERR(-ECONNREFUSED);
5851                         }
5852                 }
5853                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5854                         return NF_DROP;
5855                 secmark_perm = PACKET__SEND;
5856         } else {
5857                 /* Locally generated packet, fetch the security label from the
5858                  * associated socket. */
5859                 struct sk_security_struct *sksec = sk->sk_security;
5860                 peer_sid = sksec->sid;
5861                 secmark_perm = PACKET__SEND;
5862         }
5863
5864         ad.type = LSM_AUDIT_DATA_NET;
5865         ad.u.net = &net;
5866         ad.u.net->netif = ifindex;
5867         ad.u.net->family = family;
5868         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5869                 return NF_DROP;
5870
5871         if (secmark_active)
5872                 if (avc_has_perm(&selinux_state,
5873                                  peer_sid, skb->secmark,
5874                                  SECCLASS_PACKET, secmark_perm, &ad))
5875                         return NF_DROP_ERR(-ECONNREFUSED);
5876
5877         if (peerlbl_active) {
5878                 u32 if_sid;
5879                 u32 node_sid;
5880
5881                 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5882                         return NF_DROP;
5883                 if (avc_has_perm(&selinux_state,
5884                                  peer_sid, if_sid,
5885                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5886                         return NF_DROP_ERR(-ECONNREFUSED);
5887
5888                 if (sel_netnode_sid(addrp, family, &node_sid))
5889                         return NF_DROP;
5890                 if (avc_has_perm(&selinux_state,
5891                                  peer_sid, node_sid,
5892                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5893                         return NF_DROP_ERR(-ECONNREFUSED);
5894         }
5895
5896         return NF_ACCEPT;
5897 }
5898
5899 static unsigned int selinux_ipv4_postroute(void *priv,
5900                                            struct sk_buff *skb,
5901                                            const struct nf_hook_state *state)
5902 {
5903         return selinux_ip_postroute(skb, state->out, PF_INET);
5904 }
5905
5906 #if IS_ENABLED(CONFIG_IPV6)
5907 static unsigned int selinux_ipv6_postroute(void *priv,
5908                                            struct sk_buff *skb,
5909                                            const struct nf_hook_state *state)
5910 {
5911         return selinux_ip_postroute(skb, state->out, PF_INET6);
5912 }
5913 #endif  /* IPV6 */
5914
5915 #endif  /* CONFIG_NETFILTER */
5916
5917 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5918 {
5919         return selinux_nlmsg_perm(sk, skb);
5920 }
5921
5922 static int ipc_alloc_security(struct kern_ipc_perm *perm,
5923                               u16 sclass)
5924 {
5925         struct ipc_security_struct *isec;
5926
5927         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5928         if (!isec)
5929                 return -ENOMEM;
5930
5931         isec->sclass = sclass;
5932         isec->sid = current_sid();
5933         perm->security = isec;
5934
5935         return 0;
5936 }
5937
5938 static void ipc_free_security(struct kern_ipc_perm *perm)
5939 {
5940         struct ipc_security_struct *isec = perm->security;
5941         perm->security = NULL;
5942         kfree(isec);
5943 }
5944
5945 static int msg_msg_alloc_security(struct msg_msg *msg)
5946 {
5947         struct msg_security_struct *msec;
5948
5949         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5950         if (!msec)
5951                 return -ENOMEM;
5952
5953         msec->sid = SECINITSID_UNLABELED;
5954         msg->security = msec;
5955
5956         return 0;
5957 }
5958
5959 static void msg_msg_free_security(struct msg_msg *msg)
5960 {
5961         struct msg_security_struct *msec = msg->security;
5962
5963         msg->security = NULL;
5964         kfree(msec);
5965 }
5966
5967 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5968                         u32 perms)
5969 {
5970         struct ipc_security_struct *isec;
5971         struct common_audit_data ad;
5972         u32 sid = current_sid();
5973
5974         isec = ipc_perms->security;
5975
5976         ad.type = LSM_AUDIT_DATA_IPC;
5977         ad.u.ipc_id = ipc_perms->key;
5978
5979         return avc_has_perm(&selinux_state,
5980                             sid, isec->sid, isec->sclass, perms, &ad);
5981 }
5982
5983 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5984 {
5985         return msg_msg_alloc_security(msg);
5986 }
5987
5988 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5989 {
5990         msg_msg_free_security(msg);
5991 }
5992
5993 /* message queue security operations */
5994 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5995 {
5996         struct ipc_security_struct *isec;
5997         struct common_audit_data ad;
5998         u32 sid = current_sid();
5999         int rc;
6000
6001         rc = ipc_alloc_security(msq, SECCLASS_MSGQ);
6002         if (rc)
6003                 return rc;
6004
6005         isec = msq->security;
6006
6007         ad.type = LSM_AUDIT_DATA_IPC;
6008         ad.u.ipc_id = msq->key;
6009
6010         rc = avc_has_perm(&selinux_state,
6011                           sid, isec->sid, SECCLASS_MSGQ,
6012                           MSGQ__CREATE, &ad);
6013         if (rc) {
6014                 ipc_free_security(msq);
6015                 return rc;
6016         }
6017         return 0;
6018 }
6019
6020 static void selinux_msg_queue_free_security(struct kern_ipc_perm *msq)
6021 {
6022         ipc_free_security(msq);
6023 }
6024
6025 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6026 {
6027         struct ipc_security_struct *isec;
6028         struct common_audit_data ad;
6029         u32 sid = current_sid();
6030
6031         isec = msq->security;
6032
6033         ad.type = LSM_AUDIT_DATA_IPC;
6034         ad.u.ipc_id = msq->key;
6035
6036         return avc_has_perm(&selinux_state,
6037                             sid, isec->sid, SECCLASS_MSGQ,
6038                             MSGQ__ASSOCIATE, &ad);
6039 }
6040
6041 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6042 {
6043         int err;
6044         int perms;
6045
6046         switch (cmd) {
6047         case IPC_INFO:
6048         case MSG_INFO:
6049                 /* No specific object, just general system-wide information. */
6050                 return avc_has_perm(&selinux_state,
6051                                     current_sid(), SECINITSID_KERNEL,
6052                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6053         case IPC_STAT:
6054         case MSG_STAT:
6055         case MSG_STAT_ANY:
6056                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6057                 break;
6058         case IPC_SET:
6059                 perms = MSGQ__SETATTR;
6060                 break;
6061         case IPC_RMID:
6062                 perms = MSGQ__DESTROY;
6063                 break;
6064         default:
6065                 return 0;
6066         }
6067
6068         err = ipc_has_perm(msq, perms);
6069         return err;
6070 }
6071
6072 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6073 {
6074         struct ipc_security_struct *isec;
6075         struct msg_security_struct *msec;
6076         struct common_audit_data ad;
6077         u32 sid = current_sid();
6078         int rc;
6079
6080         isec = msq->security;
6081         msec = msg->security;
6082
6083         /*
6084          * First time through, need to assign label to the message
6085          */
6086         if (msec->sid == SECINITSID_UNLABELED) {
6087                 /*
6088                  * Compute new sid based on current process and
6089                  * message queue this message will be stored in
6090                  */
6091                 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6092                                              SECCLASS_MSG, NULL, &msec->sid);
6093                 if (rc)
6094                         return rc;
6095         }
6096
6097         ad.type = LSM_AUDIT_DATA_IPC;
6098         ad.u.ipc_id = msq->key;
6099
6100         /* Can this process write to the queue? */
6101         rc = avc_has_perm(&selinux_state,
6102                           sid, isec->sid, SECCLASS_MSGQ,
6103                           MSGQ__WRITE, &ad);
6104         if (!rc)
6105                 /* Can this process send the message */
6106                 rc = avc_has_perm(&selinux_state,
6107                                   sid, msec->sid, SECCLASS_MSG,
6108                                   MSG__SEND, &ad);
6109         if (!rc)
6110                 /* Can the message be put in the queue? */
6111                 rc = avc_has_perm(&selinux_state,
6112                                   msec->sid, isec->sid, SECCLASS_MSGQ,
6113                                   MSGQ__ENQUEUE, &ad);
6114
6115         return rc;
6116 }
6117
6118 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6119                                     struct task_struct *target,
6120                                     long type, int mode)
6121 {
6122         struct ipc_security_struct *isec;
6123         struct msg_security_struct *msec;
6124         struct common_audit_data ad;
6125         u32 sid = task_sid(target);
6126         int rc;
6127
6128         isec = msq->security;
6129         msec = msg->security;
6130
6131         ad.type = LSM_AUDIT_DATA_IPC;
6132         ad.u.ipc_id = msq->key;
6133
6134         rc = avc_has_perm(&selinux_state,
6135                           sid, isec->sid,
6136                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6137         if (!rc)
6138                 rc = avc_has_perm(&selinux_state,
6139                                   sid, msec->sid,
6140                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6141         return rc;
6142 }
6143
6144 /* Shared Memory security operations */
6145 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6146 {
6147         struct ipc_security_struct *isec;
6148         struct common_audit_data ad;
6149         u32 sid = current_sid();
6150         int rc;
6151
6152         rc = ipc_alloc_security(shp, SECCLASS_SHM);
6153         if (rc)
6154                 return rc;
6155
6156         isec = shp->security;
6157
6158         ad.type = LSM_AUDIT_DATA_IPC;
6159         ad.u.ipc_id = shp->key;
6160
6161         rc = avc_has_perm(&selinux_state,
6162                           sid, isec->sid, SECCLASS_SHM,
6163                           SHM__CREATE, &ad);
6164         if (rc) {
6165                 ipc_free_security(shp);
6166                 return rc;
6167         }
6168         return 0;
6169 }
6170
6171 static void selinux_shm_free_security(struct kern_ipc_perm *shp)
6172 {
6173         ipc_free_security(shp);
6174 }
6175
6176 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6177 {
6178         struct ipc_security_struct *isec;
6179         struct common_audit_data ad;
6180         u32 sid = current_sid();
6181
6182         isec = shp->security;
6183
6184         ad.type = LSM_AUDIT_DATA_IPC;
6185         ad.u.ipc_id = shp->key;
6186
6187         return avc_has_perm(&selinux_state,
6188                             sid, isec->sid, SECCLASS_SHM,
6189                             SHM__ASSOCIATE, &ad);
6190 }
6191
6192 /* Note, at this point, shp is locked down */
6193 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6194 {
6195         int perms;
6196         int err;
6197
6198         switch (cmd) {
6199         case IPC_INFO:
6200         case SHM_INFO:
6201                 /* No specific object, just general system-wide information. */
6202                 return avc_has_perm(&selinux_state,
6203                                     current_sid(), SECINITSID_KERNEL,
6204                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6205         case IPC_STAT:
6206         case SHM_STAT:
6207         case SHM_STAT_ANY:
6208                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6209                 break;
6210         case IPC_SET:
6211                 perms = SHM__SETATTR;
6212                 break;
6213         case SHM_LOCK:
6214         case SHM_UNLOCK:
6215                 perms = SHM__LOCK;
6216                 break;
6217         case IPC_RMID:
6218                 perms = SHM__DESTROY;
6219                 break;
6220         default:
6221                 return 0;
6222         }
6223
6224         err = ipc_has_perm(shp, perms);
6225         return err;
6226 }
6227
6228 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6229                              char __user *shmaddr, int shmflg)
6230 {
6231         u32 perms;
6232
6233         if (shmflg & SHM_RDONLY)
6234                 perms = SHM__READ;
6235         else
6236                 perms = SHM__READ | SHM__WRITE;
6237
6238         return ipc_has_perm(shp, perms);
6239 }
6240
6241 /* Semaphore security operations */
6242 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6243 {
6244         struct ipc_security_struct *isec;
6245         struct common_audit_data ad;
6246         u32 sid = current_sid();
6247         int rc;
6248
6249         rc = ipc_alloc_security(sma, SECCLASS_SEM);
6250         if (rc)
6251                 return rc;
6252
6253         isec = sma->security;
6254
6255         ad.type = LSM_AUDIT_DATA_IPC;
6256         ad.u.ipc_id = sma->key;
6257
6258         rc = avc_has_perm(&selinux_state,
6259                           sid, isec->sid, SECCLASS_SEM,
6260                           SEM__CREATE, &ad);
6261         if (rc) {
6262                 ipc_free_security(sma);
6263                 return rc;
6264         }
6265         return 0;
6266 }
6267
6268 static void selinux_sem_free_security(struct kern_ipc_perm *sma)
6269 {
6270         ipc_free_security(sma);
6271 }
6272
6273 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6274 {
6275         struct ipc_security_struct *isec;
6276         struct common_audit_data ad;
6277         u32 sid = current_sid();
6278
6279         isec = sma->security;
6280
6281         ad.type = LSM_AUDIT_DATA_IPC;
6282         ad.u.ipc_id = sma->key;
6283
6284         return avc_has_perm(&selinux_state,
6285                             sid, isec->sid, SECCLASS_SEM,
6286                             SEM__ASSOCIATE, &ad);
6287 }
6288
6289 /* Note, at this point, sma is locked down */
6290 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6291 {
6292         int err;
6293         u32 perms;
6294
6295         switch (cmd) {
6296         case IPC_INFO:
6297         case SEM_INFO:
6298                 /* No specific object, just general system-wide information. */
6299                 return avc_has_perm(&selinux_state,
6300                                     current_sid(), SECINITSID_KERNEL,
6301                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6302         case GETPID:
6303         case GETNCNT:
6304         case GETZCNT:
6305                 perms = SEM__GETATTR;
6306                 break;
6307         case GETVAL:
6308         case GETALL:
6309                 perms = SEM__READ;
6310                 break;
6311         case SETVAL:
6312         case SETALL:
6313                 perms = SEM__WRITE;
6314                 break;
6315         case IPC_RMID:
6316                 perms = SEM__DESTROY;
6317                 break;
6318         case IPC_SET:
6319                 perms = SEM__SETATTR;
6320                 break;
6321         case IPC_STAT:
6322         case SEM_STAT:
6323         case SEM_STAT_ANY:
6324                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6325                 break;
6326         default:
6327                 return 0;
6328         }
6329
6330         err = ipc_has_perm(sma, perms);
6331         return err;
6332 }
6333
6334 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6335                              struct sembuf *sops, unsigned nsops, int alter)
6336 {
6337         u32 perms;
6338
6339         if (alter)
6340                 perms = SEM__READ | SEM__WRITE;
6341         else
6342                 perms = SEM__READ;
6343
6344         return ipc_has_perm(sma, perms);
6345 }
6346
6347 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6348 {
6349         u32 av = 0;
6350
6351         av = 0;
6352         if (flag & S_IRUGO)
6353                 av |= IPC__UNIX_READ;
6354         if (flag & S_IWUGO)
6355                 av |= IPC__UNIX_WRITE;
6356
6357         if (av == 0)
6358                 return 0;
6359
6360         return ipc_has_perm(ipcp, av);
6361 }
6362
6363 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6364 {
6365         struct ipc_security_struct *isec = ipcp->security;
6366         *secid = isec->sid;
6367 }
6368
6369 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6370 {
6371         if (inode)
6372                 inode_doinit_with_dentry(inode, dentry);
6373 }
6374
6375 static int selinux_getprocattr(struct task_struct *p,
6376                                char *name, char **value)
6377 {
6378         const struct task_security_struct *__tsec;
6379         u32 sid;
6380         int error;
6381         unsigned len;
6382
6383         rcu_read_lock();
6384         __tsec = __task_cred(p)->security;
6385
6386         if (current != p) {
6387                 error = avc_has_perm(&selinux_state,
6388                                      current_sid(), __tsec->sid,
6389                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6390                 if (error)
6391                         goto bad;
6392         }
6393
6394         if (!strcmp(name, "current"))
6395                 sid = __tsec->sid;
6396         else if (!strcmp(name, "prev"))
6397                 sid = __tsec->osid;
6398         else if (!strcmp(name, "exec"))
6399                 sid = __tsec->exec_sid;
6400         else if (!strcmp(name, "fscreate"))
6401                 sid = __tsec->create_sid;
6402         else if (!strcmp(name, "keycreate"))
6403                 sid = __tsec->keycreate_sid;
6404         else if (!strcmp(name, "sockcreate"))
6405                 sid = __tsec->sockcreate_sid;
6406         else {
6407                 error = -EINVAL;
6408                 goto bad;
6409         }
6410         rcu_read_unlock();
6411
6412         if (!sid)
6413                 return 0;
6414
6415         error = security_sid_to_context(&selinux_state, sid, value, &len);
6416         if (error)
6417                 return error;
6418         return len;
6419
6420 bad:
6421         rcu_read_unlock();
6422         return error;
6423 }
6424
6425 static int selinux_setprocattr(const char *name, void *value, size_t size)
6426 {
6427         struct task_security_struct *tsec;
6428         struct cred *new;
6429         u32 mysid = current_sid(), sid = 0, ptsid;
6430         int error;
6431         char *str = value;
6432
6433         /*
6434          * Basic control over ability to set these attributes at all.
6435          */
6436         if (!strcmp(name, "exec"))
6437                 error = avc_has_perm(&selinux_state,
6438                                      mysid, mysid, SECCLASS_PROCESS,
6439                                      PROCESS__SETEXEC, NULL);
6440         else if (!strcmp(name, "fscreate"))
6441                 error = avc_has_perm(&selinux_state,
6442                                      mysid, mysid, SECCLASS_PROCESS,
6443                                      PROCESS__SETFSCREATE, NULL);
6444         else if (!strcmp(name, "keycreate"))
6445                 error = avc_has_perm(&selinux_state,
6446                                      mysid, mysid, SECCLASS_PROCESS,
6447                                      PROCESS__SETKEYCREATE, NULL);
6448         else if (!strcmp(name, "sockcreate"))
6449                 error = avc_has_perm(&selinux_state,
6450                                      mysid, mysid, SECCLASS_PROCESS,
6451                                      PROCESS__SETSOCKCREATE, NULL);
6452         else if (!strcmp(name, "current"))
6453                 error = avc_has_perm(&selinux_state,
6454                                      mysid, mysid, SECCLASS_PROCESS,
6455                                      PROCESS__SETCURRENT, NULL);
6456         else
6457                 error = -EINVAL;
6458         if (error)
6459                 return error;
6460
6461         /* Obtain a SID for the context, if one was specified. */
6462         if (size && str[0] && str[0] != '\n') {
6463                 if (str[size-1] == '\n') {
6464                         str[size-1] = 0;
6465                         size--;
6466                 }
6467                 error = security_context_to_sid(&selinux_state, value, size,
6468                                                 &sid, GFP_KERNEL);
6469                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6470                         if (!has_cap_mac_admin(true)) {
6471                                 struct audit_buffer *ab;
6472                                 size_t audit_size;
6473
6474                                 /* We strip a nul only if it is at the end, otherwise the
6475                                  * context contains a nul and we should audit that */
6476                                 if (str[size - 1] == '\0')
6477                                         audit_size = size - 1;
6478                                 else
6479                                         audit_size = size;
6480                                 ab = audit_log_start(audit_context(),
6481                                                      GFP_ATOMIC,
6482                                                      AUDIT_SELINUX_ERR);
6483                                 audit_log_format(ab, "op=fscreate invalid_context=");
6484                                 audit_log_n_untrustedstring(ab, value, audit_size);
6485                                 audit_log_end(ab);
6486
6487                                 return error;
6488                         }
6489                         error = security_context_to_sid_force(
6490                                                       &selinux_state,
6491                                                       value, size, &sid);
6492                 }
6493                 if (error)
6494                         return error;
6495         }
6496
6497         new = prepare_creds();
6498         if (!new)
6499                 return -ENOMEM;
6500
6501         /* Permission checking based on the specified context is
6502            performed during the actual operation (execve,
6503            open/mkdir/...), when we know the full context of the
6504            operation.  See selinux_bprm_set_creds for the execve
6505            checks and may_create for the file creation checks. The
6506            operation will then fail if the context is not permitted. */
6507         tsec = new->security;
6508         if (!strcmp(name, "exec")) {
6509                 tsec->exec_sid = sid;
6510         } else if (!strcmp(name, "fscreate")) {
6511                 tsec->create_sid = sid;
6512         } else if (!strcmp(name, "keycreate")) {
6513                 error = avc_has_perm(&selinux_state,
6514                                      mysid, sid, SECCLASS_KEY, KEY__CREATE,
6515                                      NULL);
6516                 if (error)
6517                         goto abort_change;
6518                 tsec->keycreate_sid = sid;
6519         } else if (!strcmp(name, "sockcreate")) {
6520                 tsec->sockcreate_sid = sid;
6521         } else if (!strcmp(name, "current")) {
6522                 error = -EINVAL;
6523                 if (sid == 0)
6524                         goto abort_change;
6525
6526                 /* Only allow single threaded processes to change context */
6527                 error = -EPERM;
6528                 if (!current_is_single_threaded()) {
6529                         error = security_bounded_transition(&selinux_state,
6530                                                             tsec->sid, sid);
6531                         if (error)
6532                                 goto abort_change;
6533                 }
6534
6535                 /* Check permissions for the transition. */
6536                 error = avc_has_perm(&selinux_state,
6537                                      tsec->sid, sid, SECCLASS_PROCESS,
6538                                      PROCESS__DYNTRANSITION, NULL);
6539                 if (error)
6540                         goto abort_change;
6541
6542                 /* Check for ptracing, and update the task SID if ok.
6543                    Otherwise, leave SID unchanged and fail. */
6544                 ptsid = ptrace_parent_sid();
6545                 if (ptsid != 0) {
6546                         error = avc_has_perm(&selinux_state,
6547                                              ptsid, sid, SECCLASS_PROCESS,
6548                                              PROCESS__PTRACE, NULL);
6549                         if (error)
6550                                 goto abort_change;
6551                 }
6552
6553                 tsec->sid = sid;
6554         } else {
6555                 error = -EINVAL;
6556                 goto abort_change;
6557         }
6558
6559         commit_creds(new);
6560         return size;
6561
6562 abort_change:
6563         abort_creds(new);
6564         return error;
6565 }
6566
6567 static int selinux_ismaclabel(const char *name)
6568 {
6569         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6570 }
6571
6572 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6573 {
6574         return security_sid_to_context(&selinux_state, secid,
6575                                        secdata, seclen);
6576 }
6577
6578 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6579 {
6580         return security_context_to_sid(&selinux_state, secdata, seclen,
6581                                        secid, GFP_KERNEL);
6582 }
6583
6584 static void selinux_release_secctx(char *secdata, u32 seclen)
6585 {
6586         kfree(secdata);
6587 }
6588
6589 static void selinux_inode_invalidate_secctx(struct inode *inode)
6590 {
6591         struct inode_security_struct *isec = inode->i_security;
6592
6593         spin_lock(&isec->lock);
6594         isec->initialized = LABEL_INVALID;
6595         spin_unlock(&isec->lock);
6596 }
6597
6598 /*
6599  *      called with inode->i_mutex locked
6600  */
6601 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6602 {
6603         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6604 }
6605
6606 /*
6607  *      called with inode->i_mutex locked
6608  */
6609 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6610 {
6611         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6612 }
6613
6614 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6615 {
6616         int len = 0;
6617         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6618                                                 ctx, true);
6619         if (len < 0)
6620                 return len;
6621         *ctxlen = len;
6622         return 0;
6623 }
6624 #ifdef CONFIG_KEYS
6625
6626 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6627                              unsigned long flags)
6628 {
6629         const struct task_security_struct *tsec;
6630         struct key_security_struct *ksec;
6631
6632         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6633         if (!ksec)
6634                 return -ENOMEM;
6635
6636         tsec = cred->security;
6637         if (tsec->keycreate_sid)
6638                 ksec->sid = tsec->keycreate_sid;
6639         else
6640                 ksec->sid = tsec->sid;
6641
6642         k->security = ksec;
6643         return 0;
6644 }
6645
6646 static void selinux_key_free(struct key *k)
6647 {
6648         struct key_security_struct *ksec = k->security;
6649
6650         k->security = NULL;
6651         kfree(ksec);
6652 }
6653
6654 static int selinux_key_permission(key_ref_t key_ref,
6655                                   const struct cred *cred,
6656                                   unsigned perm)
6657 {
6658         struct key *key;
6659         struct key_security_struct *ksec;
6660         u32 sid;
6661
6662         /* if no specific permissions are requested, we skip the
6663            permission check. No serious, additional covert channels
6664            appear to be created. */
6665         if (perm == 0)
6666                 return 0;
6667
6668         sid = cred_sid(cred);
6669
6670         key = key_ref_to_ptr(key_ref);
6671         ksec = key->security;
6672
6673         return avc_has_perm(&selinux_state,
6674                             sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6675 }
6676
6677 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6678 {
6679         struct key_security_struct *ksec = key->security;
6680         char *context = NULL;
6681         unsigned len;
6682         int rc;
6683
6684         rc = security_sid_to_context(&selinux_state, ksec->sid,
6685                                      &context, &len);
6686         if (!rc)
6687                 rc = len;
6688         *_buffer = context;
6689         return rc;
6690 }
6691 #endif
6692
6693 #ifdef CONFIG_SECURITY_INFINIBAND
6694 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6695 {
6696         struct common_audit_data ad;
6697         int err;
6698         u32 sid = 0;
6699         struct ib_security_struct *sec = ib_sec;
6700         struct lsm_ibpkey_audit ibpkey;
6701
6702         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6703         if (err)
6704                 return err;
6705
6706         ad.type = LSM_AUDIT_DATA_IBPKEY;
6707         ibpkey.subnet_prefix = subnet_prefix;
6708         ibpkey.pkey = pkey_val;
6709         ad.u.ibpkey = &ibpkey;
6710         return avc_has_perm(&selinux_state,
6711                             sec->sid, sid,
6712                             SECCLASS_INFINIBAND_PKEY,
6713                             INFINIBAND_PKEY__ACCESS, &ad);
6714 }
6715
6716 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6717                                             u8 port_num)
6718 {
6719         struct common_audit_data ad;
6720         int err;
6721         u32 sid = 0;
6722         struct ib_security_struct *sec = ib_sec;
6723         struct lsm_ibendport_audit ibendport;
6724
6725         err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6726                                       &sid);
6727
6728         if (err)
6729                 return err;
6730
6731         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6732         strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6733         ibendport.port = port_num;
6734         ad.u.ibendport = &ibendport;
6735         return avc_has_perm(&selinux_state,
6736                             sec->sid, sid,
6737                             SECCLASS_INFINIBAND_ENDPORT,
6738                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6739 }
6740
6741 static int selinux_ib_alloc_security(void **ib_sec)
6742 {
6743         struct ib_security_struct *sec;
6744
6745         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6746         if (!sec)
6747                 return -ENOMEM;
6748         sec->sid = current_sid();
6749
6750         *ib_sec = sec;
6751         return 0;
6752 }
6753
6754 static void selinux_ib_free_security(void *ib_sec)
6755 {
6756         kfree(ib_sec);
6757 }
6758 #endif
6759
6760 #ifdef CONFIG_BPF_SYSCALL
6761 static int selinux_bpf(int cmd, union bpf_attr *attr,
6762                                      unsigned int size)
6763 {
6764         u32 sid = current_sid();
6765         int ret;
6766
6767         switch (cmd) {
6768         case BPF_MAP_CREATE:
6769                 ret = avc_has_perm(&selinux_state,
6770                                    sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6771                                    NULL);
6772                 break;
6773         case BPF_PROG_LOAD:
6774                 ret = avc_has_perm(&selinux_state,
6775                                    sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6776                                    NULL);
6777                 break;
6778         default:
6779                 ret = 0;
6780                 break;
6781         }
6782
6783         return ret;
6784 }
6785
6786 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6787 {
6788         u32 av = 0;
6789
6790         if (fmode & FMODE_READ)
6791                 av |= BPF__MAP_READ;
6792         if (fmode & FMODE_WRITE)
6793                 av |= BPF__MAP_WRITE;
6794         return av;
6795 }
6796
6797 /* This function will check the file pass through unix socket or binder to see
6798  * if it is a bpf related object. And apply correspinding checks on the bpf
6799  * object based on the type. The bpf maps and programs, not like other files and
6800  * socket, are using a shared anonymous inode inside the kernel as their inode.
6801  * So checking that inode cannot identify if the process have privilege to
6802  * access the bpf object and that's why we have to add this additional check in
6803  * selinux_file_receive and selinux_binder_transfer_files.
6804  */
6805 static int bpf_fd_pass(struct file *file, u32 sid)
6806 {
6807         struct bpf_security_struct *bpfsec;
6808         struct bpf_prog *prog;
6809         struct bpf_map *map;
6810         int ret;
6811
6812         if (file->f_op == &bpf_map_fops) {
6813                 map = file->private_data;
6814                 bpfsec = map->security;
6815                 ret = avc_has_perm(&selinux_state,
6816                                    sid, bpfsec->sid, SECCLASS_BPF,
6817                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6818                 if (ret)
6819                         return ret;
6820         } else if (file->f_op == &bpf_prog_fops) {
6821                 prog = file->private_data;
6822                 bpfsec = prog->aux->security;
6823                 ret = avc_has_perm(&selinux_state,
6824                                    sid, bpfsec->sid, SECCLASS_BPF,
6825                                    BPF__PROG_RUN, NULL);
6826                 if (ret)
6827                         return ret;
6828         }
6829         return 0;
6830 }
6831
6832 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6833 {
6834         u32 sid = current_sid();
6835         struct bpf_security_struct *bpfsec;
6836
6837         bpfsec = map->security;
6838         return avc_has_perm(&selinux_state,
6839                             sid, bpfsec->sid, SECCLASS_BPF,
6840                             bpf_map_fmode_to_av(fmode), NULL);
6841 }
6842
6843 static int selinux_bpf_prog(struct bpf_prog *prog)
6844 {
6845         u32 sid = current_sid();
6846         struct bpf_security_struct *bpfsec;
6847
6848         bpfsec = prog->aux->security;
6849         return avc_has_perm(&selinux_state,
6850                             sid, bpfsec->sid, SECCLASS_BPF,
6851                             BPF__PROG_RUN, NULL);
6852 }
6853
6854 static int selinux_bpf_map_alloc(struct bpf_map *map)
6855 {
6856         struct bpf_security_struct *bpfsec;
6857
6858         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6859         if (!bpfsec)
6860                 return -ENOMEM;
6861
6862         bpfsec->sid = current_sid();
6863         map->security = bpfsec;
6864
6865         return 0;
6866 }
6867
6868 static void selinux_bpf_map_free(struct bpf_map *map)
6869 {
6870         struct bpf_security_struct *bpfsec = map->security;
6871
6872         map->security = NULL;
6873         kfree(bpfsec);
6874 }
6875
6876 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6877 {
6878         struct bpf_security_struct *bpfsec;
6879
6880         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6881         if (!bpfsec)
6882                 return -ENOMEM;
6883
6884         bpfsec->sid = current_sid();
6885         aux->security = bpfsec;
6886
6887         return 0;
6888 }
6889
6890 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6891 {
6892         struct bpf_security_struct *bpfsec = aux->security;
6893
6894         aux->security = NULL;
6895         kfree(bpfsec);
6896 }
6897 #endif
6898
6899 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6900         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6901         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6902         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6903         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6904
6905         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6906         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6907         LSM_HOOK_INIT(capget, selinux_capget),
6908         LSM_HOOK_INIT(capset, selinux_capset),
6909         LSM_HOOK_INIT(capable, selinux_capable),
6910         LSM_HOOK_INIT(quotactl, selinux_quotactl),
6911         LSM_HOOK_INIT(quota_on, selinux_quota_on),
6912         LSM_HOOK_INIT(syslog, selinux_syslog),
6913         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6914
6915         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6916
6917         LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6918         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6919         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6920
6921         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6922         LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6923         LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
6924         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6925         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6926         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6927         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6928         LSM_HOOK_INIT(sb_mount, selinux_mount),
6929         LSM_HOOK_INIT(sb_umount, selinux_umount),
6930         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6931         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6932         LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
6933
6934         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6935         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6936
6937         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6938         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6939         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6940         LSM_HOOK_INIT(inode_create, selinux_inode_create),
6941         LSM_HOOK_INIT(inode_link, selinux_inode_link),
6942         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6943         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6944         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6945         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6946         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6947         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6948         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6949         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6950         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6951         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6952         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6953         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6954         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6955         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6956         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6957         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6958         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6959         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6960         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6961         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6962         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6963         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6964
6965         LSM_HOOK_INIT(file_permission, selinux_file_permission),
6966         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6967         LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6968         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6969         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6970         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6971         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6972         LSM_HOOK_INIT(file_lock, selinux_file_lock),
6973         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6974         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6975         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6976         LSM_HOOK_INIT(file_receive, selinux_file_receive),
6977
6978         LSM_HOOK_INIT(file_open, selinux_file_open),
6979
6980         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6981         LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6982         LSM_HOOK_INIT(cred_free, selinux_cred_free),
6983         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6984         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6985         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
6986         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6987         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6988         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6989         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
6990         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6991         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6992         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6993         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6994         LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6995         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6996         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6997         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6998         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6999         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7000         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7001         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7002         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7003         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7004         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7005
7006         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7007         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7008
7009         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7010         LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
7011
7012         LSM_HOOK_INIT(msg_queue_alloc_security,
7013                         selinux_msg_queue_alloc_security),
7014         LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
7015         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7016         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7017         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7018         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7019
7020         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7021         LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
7022         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7023         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7024         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7025
7026         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7027         LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
7028         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7029         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7030         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7031
7032         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7033
7034         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7035         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7036
7037         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7038         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7039         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7040         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7041         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7042         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7043         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7044         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7045
7046         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7047         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7048
7049         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7050         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7051         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7052         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7053         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7054         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7055         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7056         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7057         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7058         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7059         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7060         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7061         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7062         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7063         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7064         LSM_HOOK_INIT(socket_getpeersec_stream,
7065                         selinux_socket_getpeersec_stream),
7066         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7067         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7068         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7069         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7070         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7071         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7072         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7073         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7074         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7075         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7076         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7077         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7078         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7079         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7080         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7081         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7082         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7083         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7084         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7085         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7086         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7087         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7088 #ifdef CONFIG_SECURITY_INFINIBAND
7089         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7090         LSM_HOOK_INIT(ib_endport_manage_subnet,
7091                       selinux_ib_endport_manage_subnet),
7092         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7093         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7094 #endif
7095 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7096         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7097         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7098         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7099         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7100         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7101         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7102                         selinux_xfrm_state_alloc_acquire),
7103         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7104         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7105         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7106         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7107                         selinux_xfrm_state_pol_flow_match),
7108         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7109 #endif
7110
7111 #ifdef CONFIG_KEYS
7112         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7113         LSM_HOOK_INIT(key_free, selinux_key_free),
7114         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7115         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7116 #endif
7117
7118 #ifdef CONFIG_AUDIT
7119         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7120         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7121         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7122         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7123 #endif
7124
7125 #ifdef CONFIG_BPF_SYSCALL
7126         LSM_HOOK_INIT(bpf, selinux_bpf),
7127         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7128         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7129         LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7130         LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7131         LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7132         LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7133 #endif
7134 };
7135
7136 static __init int selinux_init(void)
7137 {
7138         if (!security_module_enable("selinux")) {
7139                 selinux_enabled = 0;
7140                 return 0;
7141         }
7142
7143         if (!selinux_enabled) {
7144                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
7145                 return 0;
7146         }
7147
7148         printk(KERN_INFO "SELinux:  Initializing.\n");
7149
7150         memset(&selinux_state, 0, sizeof(selinux_state));
7151         enforcing_set(&selinux_state, selinux_enforcing_boot);
7152         selinux_state.checkreqprot = selinux_checkreqprot_boot;
7153         selinux_ss_init(&selinux_state.ss);
7154         selinux_avc_init(&selinux_state.avc);
7155
7156         /* Set the security state for the initial task. */
7157         cred_init_security();
7158
7159         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7160
7161         sel_inode_cache = kmem_cache_create("selinux_inode_security",
7162                                             sizeof(struct inode_security_struct),
7163                                             0, SLAB_PANIC, NULL);
7164         file_security_cache = kmem_cache_create("selinux_file_security",
7165                                             sizeof(struct file_security_struct),
7166                                             0, SLAB_PANIC, NULL);
7167         avc_init();
7168
7169         avtab_cache_init();
7170
7171         ebitmap_cache_init();
7172
7173         hashtab_cache_init();
7174
7175         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7176
7177         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7178                 panic("SELinux: Unable to register AVC netcache callback\n");
7179
7180         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7181                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7182
7183         if (selinux_enforcing_boot)
7184                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
7185         else
7186                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
7187
7188         return 0;
7189 }
7190
7191 static void delayed_superblock_init(struct super_block *sb, void *unused)
7192 {
7193         superblock_doinit(sb, NULL);
7194 }
7195
7196 void selinux_complete_init(void)
7197 {
7198         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
7199
7200         /* Set up any superblocks initialized prior to the policy load. */
7201         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
7202         iterate_supers(delayed_superblock_init, NULL);
7203 }
7204
7205 /* SELinux requires early initialization in order to label
7206    all processes and objects when they are created. */
7207 security_initcall(selinux_init);
7208
7209 #if defined(CONFIG_NETFILTER)
7210
7211 static const struct nf_hook_ops selinux_nf_ops[] = {
7212         {
7213                 .hook =         selinux_ipv4_postroute,
7214                 .pf =           NFPROTO_IPV4,
7215                 .hooknum =      NF_INET_POST_ROUTING,
7216                 .priority =     NF_IP_PRI_SELINUX_LAST,
7217         },
7218         {
7219                 .hook =         selinux_ipv4_forward,
7220                 .pf =           NFPROTO_IPV4,
7221                 .hooknum =      NF_INET_FORWARD,
7222                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7223         },
7224         {
7225                 .hook =         selinux_ipv4_output,
7226                 .pf =           NFPROTO_IPV4,
7227                 .hooknum =      NF_INET_LOCAL_OUT,
7228                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7229         },
7230 #if IS_ENABLED(CONFIG_IPV6)
7231         {
7232                 .hook =         selinux_ipv6_postroute,
7233                 .pf =           NFPROTO_IPV6,
7234                 .hooknum =      NF_INET_POST_ROUTING,
7235                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7236         },
7237         {
7238                 .hook =         selinux_ipv6_forward,
7239                 .pf =           NFPROTO_IPV6,
7240                 .hooknum =      NF_INET_FORWARD,
7241                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7242         },
7243         {
7244                 .hook =         selinux_ipv6_output,
7245                 .pf =           NFPROTO_IPV6,
7246                 .hooknum =      NF_INET_LOCAL_OUT,
7247                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7248         },
7249 #endif  /* IPV6 */
7250 };
7251
7252 static int __net_init selinux_nf_register(struct net *net)
7253 {
7254         return nf_register_net_hooks(net, selinux_nf_ops,
7255                                      ARRAY_SIZE(selinux_nf_ops));
7256 }
7257
7258 static void __net_exit selinux_nf_unregister(struct net *net)
7259 {
7260         nf_unregister_net_hooks(net, selinux_nf_ops,
7261                                 ARRAY_SIZE(selinux_nf_ops));
7262 }
7263
7264 static struct pernet_operations selinux_net_ops = {
7265         .init = selinux_nf_register,
7266         .exit = selinux_nf_unregister,
7267 };
7268
7269 static int __init selinux_nf_ip_init(void)
7270 {
7271         int err;
7272
7273         if (!selinux_enabled)
7274                 return 0;
7275
7276         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
7277
7278         err = register_pernet_subsys(&selinux_net_ops);
7279         if (err)
7280                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7281
7282         return 0;
7283 }
7284 __initcall(selinux_nf_ip_init);
7285
7286 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7287 static void selinux_nf_ip_exit(void)
7288 {
7289         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
7290
7291         unregister_pernet_subsys(&selinux_net_ops);
7292 }
7293 #endif
7294
7295 #else /* CONFIG_NETFILTER */
7296
7297 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7298 #define selinux_nf_ip_exit()
7299 #endif
7300
7301 #endif /* CONFIG_NETFILTER */
7302
7303 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7304 int selinux_disable(struct selinux_state *state)
7305 {
7306         if (state->initialized) {
7307                 /* Not permitted after initial policy load. */
7308                 return -EINVAL;
7309         }
7310
7311         if (state->disabled) {
7312                 /* Only do this once. */
7313                 return -EINVAL;
7314         }
7315
7316         state->disabled = 1;
7317
7318         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
7319
7320         selinux_enabled = 0;
7321
7322         security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7323
7324         /* Try to destroy the avc node cache */
7325         avc_disable();
7326
7327         /* Unregister netfilter hooks. */
7328         selinux_nf_ip_exit();
7329
7330         /* Unregister selinuxfs. */
7331         exit_sel_fs();
7332
7333         return 0;
7334 }
7335 #endif