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