1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * NSA Security-Enhanced Linux (SELinux) security module 4 * 5 * This file contains the SELinux hook function implementations. 6 * 7 * Authors: Stephen Smalley, <sds@tycho.nsa.gov> 8 * Chris Vance, <cvance@nai.com> 9 * Wayne Salamon, <wsalamon@nai.com> 10 * James Morris <jmorris@redhat.com> 11 * 12 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 13 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> 14 * Eric Paris <eparis@redhat.com> 15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 16 * <dgoeddel@trustedcs.com> 17 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. 18 * Paul Moore <paul@paul-moore.com> 19 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 20 * Yuichi Nakamura <ynakam@hitachisoft.jp> 21 * Copyright (C) 2016 Mellanox Technologies 22 */ 23 24 #include <linux/init.h> 25 #include <linux/kd.h> 26 #include <linux/kernel.h> 27 #include <linux/tracehook.h> 28 #include <linux/errno.h> 29 #include <linux/sched/signal.h> 30 #include <linux/sched/task.h> 31 #include <linux/lsm_hooks.h> 32 #include <linux/xattr.h> 33 #include <linux/capability.h> 34 #include <linux/unistd.h> 35 #include <linux/mm.h> 36 #include <linux/mman.h> 37 #include <linux/slab.h> 38 #include <linux/pagemap.h> 39 #include <linux/proc_fs.h> 40 #include <linux/swap.h> 41 #include <linux/spinlock.h> 42 #include <linux/syscalls.h> 43 #include <linux/dcache.h> 44 #include <linux/file.h> 45 #include <linux/fdtable.h> 46 #include <linux/namei.h> 47 #include <linux/mount.h> 48 #include <linux/fs_context.h> 49 #include <linux/fs_parser.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/sctp.h> 70 #include <net/sctp/structs.h> 71 #include <linux/quota.h> 72 #include <linux/un.h> /* for Unix socket types */ 73 #include <net/af_unix.h> /* for Unix socket types */ 74 #include <linux/parser.h> 75 #include <linux/nfs_mount.h> 76 #include <net/ipv6.h> 77 #include <linux/hugetlb.h> 78 #include <linux/personality.h> 79 #include <linux/audit.h> 80 #include <linux/string.h> 81 #include <linux/mutex.h> 82 #include <linux/posix-timers.h> 83 #include <linux/syslog.h> 84 #include <linux/user_namespace.h> 85 #include <linux/export.h> 86 #include <linux/msg.h> 87 #include <linux/shm.h> 88 #include <linux/bpf.h> 89 #include <linux/kernfs.h> 90 #include <linux/stringhash.h> /* for hashlen_string() */ 91 #include <uapi/linux/mount.h> 92 #include <linux/fsnotify.h> 93 #include <linux/fanotify.h> 94 95 #include "avc.h" 96 #include "objsec.h" 97 #include "netif.h" 98 #include "netnode.h" 99 #include "netport.h" 100 #include "ibpkey.h" 101 #include "xfrm.h" 102 #include "netlabel.h" 103 #include "audit.h" 104 #include "avc_ss.h" 105 106 struct selinux_state selinux_state; 107 108 /* SECMARK reference count */ 109 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 110 111 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 112 static int selinux_enforcing_boot __initdata; 113 114 static int __init enforcing_setup(char *str) 115 { 116 unsigned long enforcing; 117 if (!kstrtoul(str, 0, &enforcing)) 118 selinux_enforcing_boot = enforcing ? 1 : 0; 119 return 1; 120 } 121 __setup("enforcing=", enforcing_setup); 122 #else 123 #define selinux_enforcing_boot 1 124 #endif 125 126 int selinux_enabled_boot __initdata = 1; 127 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 128 static int __init selinux_enabled_setup(char *str) 129 { 130 unsigned long enabled; 131 if (!kstrtoul(str, 0, &enabled)) 132 selinux_enabled_boot = enabled ? 1 : 0; 133 return 1; 134 } 135 __setup("selinux=", selinux_enabled_setup); 136 #endif 137 138 static unsigned int selinux_checkreqprot_boot = 139 CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 140 141 static int __init checkreqprot_setup(char *str) 142 { 143 unsigned long checkreqprot; 144 145 if (!kstrtoul(str, 0, &checkreqprot)) 146 selinux_checkreqprot_boot = checkreqprot ? 1 : 0; 147 return 1; 148 } 149 __setup("checkreqprot=", checkreqprot_setup); 150 151 /** 152 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 153 * 154 * Description: 155 * This function checks the SECMARK reference counter to see if any SECMARK 156 * targets are currently configured, if the reference counter is greater than 157 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 158 * enabled, false (0) if SECMARK is disabled. If the always_check_network 159 * policy capability is enabled, SECMARK is always considered enabled. 160 * 161 */ 162 static int selinux_secmark_enabled(void) 163 { 164 return (selinux_policycap_alwaysnetwork() || 165 atomic_read(&selinux_secmark_refcount)); 166 } 167 168 /** 169 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 170 * 171 * Description: 172 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 173 * (1) if any are enabled or false (0) if neither are enabled. If the 174 * always_check_network policy capability is enabled, peer labeling 175 * is always considered enabled. 176 * 177 */ 178 static int selinux_peerlbl_enabled(void) 179 { 180 return (selinux_policycap_alwaysnetwork() || 181 netlbl_enabled() || selinux_xfrm_enabled()); 182 } 183 184 static int selinux_netcache_avc_callback(u32 event) 185 { 186 if (event == AVC_CALLBACK_RESET) { 187 sel_netif_flush(); 188 sel_netnode_flush(); 189 sel_netport_flush(); 190 synchronize_net(); 191 } 192 return 0; 193 } 194 195 static int selinux_lsm_notifier_avc_callback(u32 event) 196 { 197 if (event == AVC_CALLBACK_RESET) { 198 sel_ib_pkey_flush(); 199 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 200 } 201 202 return 0; 203 } 204 205 /* 206 * initialise the security for the init task 207 */ 208 static void cred_init_security(void) 209 { 210 struct cred *cred = (struct cred *) current->real_cred; 211 struct task_security_struct *tsec; 212 213 tsec = selinux_cred(cred); 214 tsec->osid = tsec->sid = SECINITSID_KERNEL; 215 } 216 217 /* 218 * get the security ID of a set of credentials 219 */ 220 static inline u32 cred_sid(const struct cred *cred) 221 { 222 const struct task_security_struct *tsec; 223 224 tsec = selinux_cred(cred); 225 return tsec->sid; 226 } 227 228 /* 229 * get the objective security ID of a task 230 */ 231 static inline u32 task_sid(const struct task_struct *task) 232 { 233 u32 sid; 234 235 rcu_read_lock(); 236 sid = cred_sid(__task_cred(task)); 237 rcu_read_unlock(); 238 return sid; 239 } 240 241 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 242 243 /* 244 * Try reloading inode security labels that have been marked as invalid. The 245 * @may_sleep parameter indicates when sleeping and thus reloading labels is 246 * allowed; when set to false, returns -ECHILD when the label is 247 * invalid. The @dentry parameter should be set to a dentry of the inode. 248 */ 249 static int __inode_security_revalidate(struct inode *inode, 250 struct dentry *dentry, 251 bool may_sleep) 252 { 253 struct inode_security_struct *isec = selinux_inode(inode); 254 255 might_sleep_if(may_sleep); 256 257 if (selinux_initialized(&selinux_state) && 258 isec->initialized != LABEL_INITIALIZED) { 259 if (!may_sleep) 260 return -ECHILD; 261 262 /* 263 * Try reloading the inode security label. This will fail if 264 * @opt_dentry is NULL and no dentry for this inode can be 265 * found; in that case, continue using the old label. 266 */ 267 inode_doinit_with_dentry(inode, dentry); 268 } 269 return 0; 270 } 271 272 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 273 { 274 return selinux_inode(inode); 275 } 276 277 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 278 { 279 int error; 280 281 error = __inode_security_revalidate(inode, NULL, !rcu); 282 if (error) 283 return ERR_PTR(error); 284 return selinux_inode(inode); 285 } 286 287 /* 288 * Get the security label of an inode. 289 */ 290 static struct inode_security_struct *inode_security(struct inode *inode) 291 { 292 __inode_security_revalidate(inode, NULL, true); 293 return selinux_inode(inode); 294 } 295 296 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 297 { 298 struct inode *inode = d_backing_inode(dentry); 299 300 return selinux_inode(inode); 301 } 302 303 /* 304 * Get the security label of a dentry's backing inode. 305 */ 306 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 307 { 308 struct inode *inode = d_backing_inode(dentry); 309 310 __inode_security_revalidate(inode, dentry, true); 311 return selinux_inode(inode); 312 } 313 314 static void inode_free_security(struct inode *inode) 315 { 316 struct inode_security_struct *isec = selinux_inode(inode); 317 struct superblock_security_struct *sbsec; 318 319 if (!isec) 320 return; 321 sbsec = inode->i_sb->s_security; 322 /* 323 * As not all inode security structures are in a list, we check for 324 * empty list outside of the lock to make sure that we won't waste 325 * time taking a lock doing nothing. 326 * 327 * The list_del_init() function can be safely called more than once. 328 * It should not be possible for this function to be called with 329 * concurrent list_add(), but for better safety against future changes 330 * in the code, we use list_empty_careful() here. 331 */ 332 if (!list_empty_careful(&isec->list)) { 333 spin_lock(&sbsec->isec_lock); 334 list_del_init(&isec->list); 335 spin_unlock(&sbsec->isec_lock); 336 } 337 } 338 339 static void superblock_free_security(struct super_block *sb) 340 { 341 struct superblock_security_struct *sbsec = sb->s_security; 342 sb->s_security = NULL; 343 kfree(sbsec); 344 } 345 346 struct selinux_mnt_opts { 347 const char *fscontext, *context, *rootcontext, *defcontext; 348 }; 349 350 static void selinux_free_mnt_opts(void *mnt_opts) 351 { 352 struct selinux_mnt_opts *opts = mnt_opts; 353 kfree(opts->fscontext); 354 kfree(opts->context); 355 kfree(opts->rootcontext); 356 kfree(opts->defcontext); 357 kfree(opts); 358 } 359 360 enum { 361 Opt_error = -1, 362 Opt_context = 0, 363 Opt_defcontext = 1, 364 Opt_fscontext = 2, 365 Opt_rootcontext = 3, 366 Opt_seclabel = 4, 367 }; 368 369 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 370 static struct { 371 const char *name; 372 int len; 373 int opt; 374 bool has_arg; 375 } tokens[] = { 376 A(context, true), 377 A(fscontext, true), 378 A(defcontext, true), 379 A(rootcontext, true), 380 A(seclabel, false), 381 }; 382 #undef A 383 384 static int match_opt_prefix(char *s, int l, char **arg) 385 { 386 int i; 387 388 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 389 size_t len = tokens[i].len; 390 if (len > l || memcmp(s, tokens[i].name, len)) 391 continue; 392 if (tokens[i].has_arg) { 393 if (len == l || s[len] != '=') 394 continue; 395 *arg = s + len + 1; 396 } else if (len != l) 397 continue; 398 return tokens[i].opt; 399 } 400 return Opt_error; 401 } 402 403 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 404 405 static int may_context_mount_sb_relabel(u32 sid, 406 struct superblock_security_struct *sbsec, 407 const struct cred *cred) 408 { 409 const struct task_security_struct *tsec = selinux_cred(cred); 410 int rc; 411 412 rc = avc_has_perm(&selinux_state, 413 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 414 FILESYSTEM__RELABELFROM, NULL); 415 if (rc) 416 return rc; 417 418 rc = avc_has_perm(&selinux_state, 419 tsec->sid, sid, SECCLASS_FILESYSTEM, 420 FILESYSTEM__RELABELTO, NULL); 421 return rc; 422 } 423 424 static int may_context_mount_inode_relabel(u32 sid, 425 struct superblock_security_struct *sbsec, 426 const struct cred *cred) 427 { 428 const struct task_security_struct *tsec = selinux_cred(cred); 429 int rc; 430 rc = avc_has_perm(&selinux_state, 431 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 432 FILESYSTEM__RELABELFROM, NULL); 433 if (rc) 434 return rc; 435 436 rc = avc_has_perm(&selinux_state, 437 sid, sbsec->sid, SECCLASS_FILESYSTEM, 438 FILESYSTEM__ASSOCIATE, NULL); 439 return rc; 440 } 441 442 static int selinux_is_genfs_special_handling(struct super_block *sb) 443 { 444 /* Special handling. Genfs but also in-core setxattr handler */ 445 return !strcmp(sb->s_type->name, "sysfs") || 446 !strcmp(sb->s_type->name, "pstore") || 447 !strcmp(sb->s_type->name, "debugfs") || 448 !strcmp(sb->s_type->name, "tracefs") || 449 !strcmp(sb->s_type->name, "rootfs") || 450 (selinux_policycap_cgroupseclabel() && 451 (!strcmp(sb->s_type->name, "cgroup") || 452 !strcmp(sb->s_type->name, "cgroup2"))); 453 } 454 455 static int selinux_is_sblabel_mnt(struct super_block *sb) 456 { 457 struct superblock_security_struct *sbsec = sb->s_security; 458 459 /* 460 * IMPORTANT: Double-check logic in this function when adding a new 461 * SECURITY_FS_USE_* definition! 462 */ 463 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 464 465 switch (sbsec->behavior) { 466 case SECURITY_FS_USE_XATTR: 467 case SECURITY_FS_USE_TRANS: 468 case SECURITY_FS_USE_TASK: 469 case SECURITY_FS_USE_NATIVE: 470 return 1; 471 472 case SECURITY_FS_USE_GENFS: 473 return selinux_is_genfs_special_handling(sb); 474 475 /* Never allow relabeling on context mounts */ 476 case SECURITY_FS_USE_MNTPOINT: 477 case SECURITY_FS_USE_NONE: 478 default: 479 return 0; 480 } 481 } 482 483 static int sb_finish_set_opts(struct super_block *sb) 484 { 485 struct superblock_security_struct *sbsec = sb->s_security; 486 struct dentry *root = sb->s_root; 487 struct inode *root_inode = d_backing_inode(root); 488 int rc = 0; 489 490 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 491 /* Make sure that the xattr handler exists and that no 492 error other than -ENODATA is returned by getxattr on 493 the root directory. -ENODATA is ok, as this may be 494 the first boot of the SELinux kernel before we have 495 assigned xattr values to the filesystem. */ 496 if (!(root_inode->i_opflags & IOP_XATTR)) { 497 pr_warn("SELinux: (dev %s, type %s) has no " 498 "xattr support\n", sb->s_id, sb->s_type->name); 499 rc = -EOPNOTSUPP; 500 goto out; 501 } 502 503 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 504 if (rc < 0 && rc != -ENODATA) { 505 if (rc == -EOPNOTSUPP) 506 pr_warn("SELinux: (dev %s, type " 507 "%s) has no security xattr handler\n", 508 sb->s_id, sb->s_type->name); 509 else 510 pr_warn("SELinux: (dev %s, type " 511 "%s) getxattr errno %d\n", sb->s_id, 512 sb->s_type->name, -rc); 513 goto out; 514 } 515 } 516 517 sbsec->flags |= SE_SBINITIALIZED; 518 519 /* 520 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 521 * leave the flag untouched because sb_clone_mnt_opts might be handing 522 * us a superblock that needs the flag to be cleared. 523 */ 524 if (selinux_is_sblabel_mnt(sb)) 525 sbsec->flags |= SBLABEL_MNT; 526 else 527 sbsec->flags &= ~SBLABEL_MNT; 528 529 /* Initialize the root inode. */ 530 rc = inode_doinit_with_dentry(root_inode, root); 531 532 /* Initialize any other inodes associated with the superblock, e.g. 533 inodes created prior to initial policy load or inodes created 534 during get_sb by a pseudo filesystem that directly 535 populates itself. */ 536 spin_lock(&sbsec->isec_lock); 537 while (!list_empty(&sbsec->isec_head)) { 538 struct inode_security_struct *isec = 539 list_first_entry(&sbsec->isec_head, 540 struct inode_security_struct, list); 541 struct inode *inode = isec->inode; 542 list_del_init(&isec->list); 543 spin_unlock(&sbsec->isec_lock); 544 inode = igrab(inode); 545 if (inode) { 546 if (!IS_PRIVATE(inode)) 547 inode_doinit_with_dentry(inode, NULL); 548 iput(inode); 549 } 550 spin_lock(&sbsec->isec_lock); 551 } 552 spin_unlock(&sbsec->isec_lock); 553 out: 554 return rc; 555 } 556 557 static int bad_option(struct superblock_security_struct *sbsec, char flag, 558 u32 old_sid, u32 new_sid) 559 { 560 char mnt_flags = sbsec->flags & SE_MNTMASK; 561 562 /* check if the old mount command had the same options */ 563 if (sbsec->flags & SE_SBINITIALIZED) 564 if (!(sbsec->flags & flag) || 565 (old_sid != new_sid)) 566 return 1; 567 568 /* check if we were passed the same options twice, 569 * aka someone passed context=a,context=b 570 */ 571 if (!(sbsec->flags & SE_SBINITIALIZED)) 572 if (mnt_flags & flag) 573 return 1; 574 return 0; 575 } 576 577 static int parse_sid(struct super_block *sb, const char *s, u32 *sid) 578 { 579 int rc = security_context_str_to_sid(&selinux_state, s, 580 sid, GFP_KERNEL); 581 if (rc) 582 pr_warn("SELinux: security_context_str_to_sid" 583 "(%s) failed for (dev %s, type %s) errno=%d\n", 584 s, sb->s_id, sb->s_type->name, rc); 585 return rc; 586 } 587 588 /* 589 * Allow filesystems with binary mount data to explicitly set mount point 590 * labeling information. 591 */ 592 static int selinux_set_mnt_opts(struct super_block *sb, 593 void *mnt_opts, 594 unsigned long kern_flags, 595 unsigned long *set_kern_flags) 596 { 597 const struct cred *cred = current_cred(); 598 struct superblock_security_struct *sbsec = sb->s_security; 599 struct dentry *root = sbsec->sb->s_root; 600 struct selinux_mnt_opts *opts = mnt_opts; 601 struct inode_security_struct *root_isec; 602 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 603 u32 defcontext_sid = 0; 604 int rc = 0; 605 606 mutex_lock(&sbsec->lock); 607 608 if (!selinux_initialized(&selinux_state)) { 609 if (!opts) { 610 /* Defer initialization until selinux_complete_init, 611 after the initial policy is loaded and the security 612 server is ready to handle calls. */ 613 goto out; 614 } 615 rc = -EINVAL; 616 pr_warn("SELinux: Unable to set superblock options " 617 "before the security server is initialized\n"); 618 goto out; 619 } 620 if (kern_flags && !set_kern_flags) { 621 /* Specifying internal flags without providing a place to 622 * place the results is not allowed */ 623 rc = -EINVAL; 624 goto out; 625 } 626 627 /* 628 * Binary mount data FS will come through this function twice. Once 629 * from an explicit call and once from the generic calls from the vfs. 630 * Since the generic VFS calls will not contain any security mount data 631 * we need to skip the double mount verification. 632 * 633 * This does open a hole in which we will not notice if the first 634 * mount using this sb set explict options and a second mount using 635 * this sb does not set any security options. (The first options 636 * will be used for both mounts) 637 */ 638 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 639 && !opts) 640 goto out; 641 642 root_isec = backing_inode_security_novalidate(root); 643 644 /* 645 * parse the mount options, check if they are valid sids. 646 * also check if someone is trying to mount the same sb more 647 * than once with different security options. 648 */ 649 if (opts) { 650 if (opts->fscontext) { 651 rc = parse_sid(sb, opts->fscontext, &fscontext_sid); 652 if (rc) 653 goto out; 654 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 655 fscontext_sid)) 656 goto out_double_mount; 657 sbsec->flags |= FSCONTEXT_MNT; 658 } 659 if (opts->context) { 660 rc = parse_sid(sb, opts->context, &context_sid); 661 if (rc) 662 goto out; 663 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 664 context_sid)) 665 goto out_double_mount; 666 sbsec->flags |= CONTEXT_MNT; 667 } 668 if (opts->rootcontext) { 669 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid); 670 if (rc) 671 goto out; 672 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 673 rootcontext_sid)) 674 goto out_double_mount; 675 sbsec->flags |= ROOTCONTEXT_MNT; 676 } 677 if (opts->defcontext) { 678 rc = parse_sid(sb, opts->defcontext, &defcontext_sid); 679 if (rc) 680 goto out; 681 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 682 defcontext_sid)) 683 goto out_double_mount; 684 sbsec->flags |= DEFCONTEXT_MNT; 685 } 686 } 687 688 if (sbsec->flags & SE_SBINITIALIZED) { 689 /* previously mounted with options, but not on this attempt? */ 690 if ((sbsec->flags & SE_MNTMASK) && !opts) 691 goto out_double_mount; 692 rc = 0; 693 goto out; 694 } 695 696 if (strcmp(sb->s_type->name, "proc") == 0) 697 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 698 699 if (!strcmp(sb->s_type->name, "debugfs") || 700 !strcmp(sb->s_type->name, "tracefs") || 701 !strcmp(sb->s_type->name, "binderfs") || 702 !strcmp(sb->s_type->name, "pstore")) 703 sbsec->flags |= SE_SBGENFS; 704 705 if (!strcmp(sb->s_type->name, "sysfs") || 706 !strcmp(sb->s_type->name, "cgroup") || 707 !strcmp(sb->s_type->name, "cgroup2")) 708 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 709 710 if (!sbsec->behavior) { 711 /* 712 * Determine the labeling behavior to use for this 713 * filesystem type. 714 */ 715 rc = security_fs_use(&selinux_state, sb); 716 if (rc) { 717 pr_warn("%s: security_fs_use(%s) returned %d\n", 718 __func__, sb->s_type->name, rc); 719 goto out; 720 } 721 } 722 723 /* 724 * If this is a user namespace mount and the filesystem type is not 725 * explicitly whitelisted, then no contexts are allowed on the command 726 * line and security labels must be ignored. 727 */ 728 if (sb->s_user_ns != &init_user_ns && 729 strcmp(sb->s_type->name, "tmpfs") && 730 strcmp(sb->s_type->name, "ramfs") && 731 strcmp(sb->s_type->name, "devpts")) { 732 if (context_sid || fscontext_sid || rootcontext_sid || 733 defcontext_sid) { 734 rc = -EACCES; 735 goto out; 736 } 737 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 738 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 739 rc = security_transition_sid(&selinux_state, 740 current_sid(), 741 current_sid(), 742 SECCLASS_FILE, NULL, 743 &sbsec->mntpoint_sid); 744 if (rc) 745 goto out; 746 } 747 goto out_set_opts; 748 } 749 750 /* sets the context of the superblock for the fs being mounted. */ 751 if (fscontext_sid) { 752 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 753 if (rc) 754 goto out; 755 756 sbsec->sid = fscontext_sid; 757 } 758 759 /* 760 * Switch to using mount point labeling behavior. 761 * sets the label used on all file below the mountpoint, and will set 762 * the superblock context if not already set. 763 */ 764 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 765 sbsec->behavior = SECURITY_FS_USE_NATIVE; 766 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 767 } 768 769 if (context_sid) { 770 if (!fscontext_sid) { 771 rc = may_context_mount_sb_relabel(context_sid, sbsec, 772 cred); 773 if (rc) 774 goto out; 775 sbsec->sid = context_sid; 776 } else { 777 rc = may_context_mount_inode_relabel(context_sid, sbsec, 778 cred); 779 if (rc) 780 goto out; 781 } 782 if (!rootcontext_sid) 783 rootcontext_sid = context_sid; 784 785 sbsec->mntpoint_sid = context_sid; 786 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 787 } 788 789 if (rootcontext_sid) { 790 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 791 cred); 792 if (rc) 793 goto out; 794 795 root_isec->sid = rootcontext_sid; 796 root_isec->initialized = LABEL_INITIALIZED; 797 } 798 799 if (defcontext_sid) { 800 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 801 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 802 rc = -EINVAL; 803 pr_warn("SELinux: defcontext option is " 804 "invalid for this filesystem type\n"); 805 goto out; 806 } 807 808 if (defcontext_sid != sbsec->def_sid) { 809 rc = may_context_mount_inode_relabel(defcontext_sid, 810 sbsec, cred); 811 if (rc) 812 goto out; 813 } 814 815 sbsec->def_sid = defcontext_sid; 816 } 817 818 out_set_opts: 819 rc = sb_finish_set_opts(sb); 820 out: 821 mutex_unlock(&sbsec->lock); 822 return rc; 823 out_double_mount: 824 rc = -EINVAL; 825 pr_warn("SELinux: mount invalid. Same superblock, different " 826 "security settings for (dev %s, type %s)\n", sb->s_id, 827 sb->s_type->name); 828 goto out; 829 } 830 831 static int selinux_cmp_sb_context(const struct super_block *oldsb, 832 const struct super_block *newsb) 833 { 834 struct superblock_security_struct *old = oldsb->s_security; 835 struct superblock_security_struct *new = newsb->s_security; 836 char oldflags = old->flags & SE_MNTMASK; 837 char newflags = new->flags & SE_MNTMASK; 838 839 if (oldflags != newflags) 840 goto mismatch; 841 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 842 goto mismatch; 843 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 844 goto mismatch; 845 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 846 goto mismatch; 847 if (oldflags & ROOTCONTEXT_MNT) { 848 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 849 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 850 if (oldroot->sid != newroot->sid) 851 goto mismatch; 852 } 853 return 0; 854 mismatch: 855 pr_warn("SELinux: mount invalid. Same superblock, " 856 "different security settings for (dev %s, " 857 "type %s)\n", newsb->s_id, newsb->s_type->name); 858 return -EBUSY; 859 } 860 861 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 862 struct super_block *newsb, 863 unsigned long kern_flags, 864 unsigned long *set_kern_flags) 865 { 866 int rc = 0; 867 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 868 struct superblock_security_struct *newsbsec = newsb->s_security; 869 870 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 871 int set_context = (oldsbsec->flags & CONTEXT_MNT); 872 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 873 874 /* 875 * if the parent was able to be mounted it clearly had no special lsm 876 * mount options. thus we can safely deal with this superblock later 877 */ 878 if (!selinux_initialized(&selinux_state)) 879 return 0; 880 881 /* 882 * Specifying internal flags without providing a place to 883 * place the results is not allowed. 884 */ 885 if (kern_flags && !set_kern_flags) 886 return -EINVAL; 887 888 /* how can we clone if the old one wasn't set up?? */ 889 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 890 891 /* if fs is reusing a sb, make sure that the contexts match */ 892 if (newsbsec->flags & SE_SBINITIALIZED) { 893 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 894 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 895 return selinux_cmp_sb_context(oldsb, newsb); 896 } 897 898 mutex_lock(&newsbsec->lock); 899 900 newsbsec->flags = oldsbsec->flags; 901 902 newsbsec->sid = oldsbsec->sid; 903 newsbsec->def_sid = oldsbsec->def_sid; 904 newsbsec->behavior = oldsbsec->behavior; 905 906 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 907 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 908 rc = security_fs_use(&selinux_state, newsb); 909 if (rc) 910 goto out; 911 } 912 913 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 914 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 915 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 916 } 917 918 if (set_context) { 919 u32 sid = oldsbsec->mntpoint_sid; 920 921 if (!set_fscontext) 922 newsbsec->sid = sid; 923 if (!set_rootcontext) { 924 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 925 newisec->sid = sid; 926 } 927 newsbsec->mntpoint_sid = sid; 928 } 929 if (set_rootcontext) { 930 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 931 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 932 933 newisec->sid = oldisec->sid; 934 } 935 936 sb_finish_set_opts(newsb); 937 out: 938 mutex_unlock(&newsbsec->lock); 939 return rc; 940 } 941 942 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 943 { 944 struct selinux_mnt_opts *opts = *mnt_opts; 945 946 if (token == Opt_seclabel) /* eaten and completely ignored */ 947 return 0; 948 949 if (!opts) { 950 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 951 if (!opts) 952 return -ENOMEM; 953 *mnt_opts = opts; 954 } 955 if (!s) 956 return -ENOMEM; 957 switch (token) { 958 case Opt_context: 959 if (opts->context || opts->defcontext) 960 goto Einval; 961 opts->context = s; 962 break; 963 case Opt_fscontext: 964 if (opts->fscontext) 965 goto Einval; 966 opts->fscontext = s; 967 break; 968 case Opt_rootcontext: 969 if (opts->rootcontext) 970 goto Einval; 971 opts->rootcontext = s; 972 break; 973 case Opt_defcontext: 974 if (opts->context || opts->defcontext) 975 goto Einval; 976 opts->defcontext = s; 977 break; 978 } 979 return 0; 980 Einval: 981 pr_warn(SEL_MOUNT_FAIL_MSG); 982 return -EINVAL; 983 } 984 985 static int selinux_add_mnt_opt(const char *option, const char *val, int len, 986 void **mnt_opts) 987 { 988 int token = Opt_error; 989 int rc, i; 990 991 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 992 if (strcmp(option, tokens[i].name) == 0) { 993 token = tokens[i].opt; 994 break; 995 } 996 } 997 998 if (token == Opt_error) 999 return -EINVAL; 1000 1001 if (token != Opt_seclabel) { 1002 val = kmemdup_nul(val, len, GFP_KERNEL); 1003 if (!val) { 1004 rc = -ENOMEM; 1005 goto free_opt; 1006 } 1007 } 1008 rc = selinux_add_opt(token, val, mnt_opts); 1009 if (unlikely(rc)) { 1010 kfree(val); 1011 goto free_opt; 1012 } 1013 return rc; 1014 1015 free_opt: 1016 if (*mnt_opts) { 1017 selinux_free_mnt_opts(*mnt_opts); 1018 *mnt_opts = NULL; 1019 } 1020 return rc; 1021 } 1022 1023 static int show_sid(struct seq_file *m, u32 sid) 1024 { 1025 char *context = NULL; 1026 u32 len; 1027 int rc; 1028 1029 rc = security_sid_to_context(&selinux_state, sid, 1030 &context, &len); 1031 if (!rc) { 1032 bool has_comma = context && strchr(context, ','); 1033 1034 seq_putc(m, '='); 1035 if (has_comma) 1036 seq_putc(m, '\"'); 1037 seq_escape(m, context, "\"\n\\"); 1038 if (has_comma) 1039 seq_putc(m, '\"'); 1040 } 1041 kfree(context); 1042 return rc; 1043 } 1044 1045 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1046 { 1047 struct superblock_security_struct *sbsec = sb->s_security; 1048 int rc; 1049 1050 if (!(sbsec->flags & SE_SBINITIALIZED)) 1051 return 0; 1052 1053 if (!selinux_initialized(&selinux_state)) 1054 return 0; 1055 1056 if (sbsec->flags & FSCONTEXT_MNT) { 1057 seq_putc(m, ','); 1058 seq_puts(m, FSCONTEXT_STR); 1059 rc = show_sid(m, sbsec->sid); 1060 if (rc) 1061 return rc; 1062 } 1063 if (sbsec->flags & CONTEXT_MNT) { 1064 seq_putc(m, ','); 1065 seq_puts(m, CONTEXT_STR); 1066 rc = show_sid(m, sbsec->mntpoint_sid); 1067 if (rc) 1068 return rc; 1069 } 1070 if (sbsec->flags & DEFCONTEXT_MNT) { 1071 seq_putc(m, ','); 1072 seq_puts(m, DEFCONTEXT_STR); 1073 rc = show_sid(m, sbsec->def_sid); 1074 if (rc) 1075 return rc; 1076 } 1077 if (sbsec->flags & ROOTCONTEXT_MNT) { 1078 struct dentry *root = sbsec->sb->s_root; 1079 struct inode_security_struct *isec = backing_inode_security(root); 1080 seq_putc(m, ','); 1081 seq_puts(m, ROOTCONTEXT_STR); 1082 rc = show_sid(m, isec->sid); 1083 if (rc) 1084 return rc; 1085 } 1086 if (sbsec->flags & SBLABEL_MNT) { 1087 seq_putc(m, ','); 1088 seq_puts(m, SECLABEL_STR); 1089 } 1090 return 0; 1091 } 1092 1093 static inline u16 inode_mode_to_security_class(umode_t mode) 1094 { 1095 switch (mode & S_IFMT) { 1096 case S_IFSOCK: 1097 return SECCLASS_SOCK_FILE; 1098 case S_IFLNK: 1099 return SECCLASS_LNK_FILE; 1100 case S_IFREG: 1101 return SECCLASS_FILE; 1102 case S_IFBLK: 1103 return SECCLASS_BLK_FILE; 1104 case S_IFDIR: 1105 return SECCLASS_DIR; 1106 case S_IFCHR: 1107 return SECCLASS_CHR_FILE; 1108 case S_IFIFO: 1109 return SECCLASS_FIFO_FILE; 1110 1111 } 1112 1113 return SECCLASS_FILE; 1114 } 1115 1116 static inline int default_protocol_stream(int protocol) 1117 { 1118 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1119 } 1120 1121 static inline int default_protocol_dgram(int protocol) 1122 { 1123 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1124 } 1125 1126 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1127 { 1128 int extsockclass = selinux_policycap_extsockclass(); 1129 1130 switch (family) { 1131 case PF_UNIX: 1132 switch (type) { 1133 case SOCK_STREAM: 1134 case SOCK_SEQPACKET: 1135 return SECCLASS_UNIX_STREAM_SOCKET; 1136 case SOCK_DGRAM: 1137 case SOCK_RAW: 1138 return SECCLASS_UNIX_DGRAM_SOCKET; 1139 } 1140 break; 1141 case PF_INET: 1142 case PF_INET6: 1143 switch (type) { 1144 case SOCK_STREAM: 1145 case SOCK_SEQPACKET: 1146 if (default_protocol_stream(protocol)) 1147 return SECCLASS_TCP_SOCKET; 1148 else if (extsockclass && protocol == IPPROTO_SCTP) 1149 return SECCLASS_SCTP_SOCKET; 1150 else 1151 return SECCLASS_RAWIP_SOCKET; 1152 case SOCK_DGRAM: 1153 if (default_protocol_dgram(protocol)) 1154 return SECCLASS_UDP_SOCKET; 1155 else if (extsockclass && (protocol == IPPROTO_ICMP || 1156 protocol == IPPROTO_ICMPV6)) 1157 return SECCLASS_ICMP_SOCKET; 1158 else 1159 return SECCLASS_RAWIP_SOCKET; 1160 case SOCK_DCCP: 1161 return SECCLASS_DCCP_SOCKET; 1162 default: 1163 return SECCLASS_RAWIP_SOCKET; 1164 } 1165 break; 1166 case PF_NETLINK: 1167 switch (protocol) { 1168 case NETLINK_ROUTE: 1169 return SECCLASS_NETLINK_ROUTE_SOCKET; 1170 case NETLINK_SOCK_DIAG: 1171 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1172 case NETLINK_NFLOG: 1173 return SECCLASS_NETLINK_NFLOG_SOCKET; 1174 case NETLINK_XFRM: 1175 return SECCLASS_NETLINK_XFRM_SOCKET; 1176 case NETLINK_SELINUX: 1177 return SECCLASS_NETLINK_SELINUX_SOCKET; 1178 case NETLINK_ISCSI: 1179 return SECCLASS_NETLINK_ISCSI_SOCKET; 1180 case NETLINK_AUDIT: 1181 return SECCLASS_NETLINK_AUDIT_SOCKET; 1182 case NETLINK_FIB_LOOKUP: 1183 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1184 case NETLINK_CONNECTOR: 1185 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1186 case NETLINK_NETFILTER: 1187 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1188 case NETLINK_DNRTMSG: 1189 return SECCLASS_NETLINK_DNRT_SOCKET; 1190 case NETLINK_KOBJECT_UEVENT: 1191 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1192 case NETLINK_GENERIC: 1193 return SECCLASS_NETLINK_GENERIC_SOCKET; 1194 case NETLINK_SCSITRANSPORT: 1195 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1196 case NETLINK_RDMA: 1197 return SECCLASS_NETLINK_RDMA_SOCKET; 1198 case NETLINK_CRYPTO: 1199 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1200 default: 1201 return SECCLASS_NETLINK_SOCKET; 1202 } 1203 case PF_PACKET: 1204 return SECCLASS_PACKET_SOCKET; 1205 case PF_KEY: 1206 return SECCLASS_KEY_SOCKET; 1207 case PF_APPLETALK: 1208 return SECCLASS_APPLETALK_SOCKET; 1209 } 1210 1211 if (extsockclass) { 1212 switch (family) { 1213 case PF_AX25: 1214 return SECCLASS_AX25_SOCKET; 1215 case PF_IPX: 1216 return SECCLASS_IPX_SOCKET; 1217 case PF_NETROM: 1218 return SECCLASS_NETROM_SOCKET; 1219 case PF_ATMPVC: 1220 return SECCLASS_ATMPVC_SOCKET; 1221 case PF_X25: 1222 return SECCLASS_X25_SOCKET; 1223 case PF_ROSE: 1224 return SECCLASS_ROSE_SOCKET; 1225 case PF_DECnet: 1226 return SECCLASS_DECNET_SOCKET; 1227 case PF_ATMSVC: 1228 return SECCLASS_ATMSVC_SOCKET; 1229 case PF_RDS: 1230 return SECCLASS_RDS_SOCKET; 1231 case PF_IRDA: 1232 return SECCLASS_IRDA_SOCKET; 1233 case PF_PPPOX: 1234 return SECCLASS_PPPOX_SOCKET; 1235 case PF_LLC: 1236 return SECCLASS_LLC_SOCKET; 1237 case PF_CAN: 1238 return SECCLASS_CAN_SOCKET; 1239 case PF_TIPC: 1240 return SECCLASS_TIPC_SOCKET; 1241 case PF_BLUETOOTH: 1242 return SECCLASS_BLUETOOTH_SOCKET; 1243 case PF_IUCV: 1244 return SECCLASS_IUCV_SOCKET; 1245 case PF_RXRPC: 1246 return SECCLASS_RXRPC_SOCKET; 1247 case PF_ISDN: 1248 return SECCLASS_ISDN_SOCKET; 1249 case PF_PHONET: 1250 return SECCLASS_PHONET_SOCKET; 1251 case PF_IEEE802154: 1252 return SECCLASS_IEEE802154_SOCKET; 1253 case PF_CAIF: 1254 return SECCLASS_CAIF_SOCKET; 1255 case PF_ALG: 1256 return SECCLASS_ALG_SOCKET; 1257 case PF_NFC: 1258 return SECCLASS_NFC_SOCKET; 1259 case PF_VSOCK: 1260 return SECCLASS_VSOCK_SOCKET; 1261 case PF_KCM: 1262 return SECCLASS_KCM_SOCKET; 1263 case PF_QIPCRTR: 1264 return SECCLASS_QIPCRTR_SOCKET; 1265 case PF_SMC: 1266 return SECCLASS_SMC_SOCKET; 1267 case PF_XDP: 1268 return SECCLASS_XDP_SOCKET; 1269 #if PF_MAX > 45 1270 #error New address family defined, please update this function. 1271 #endif 1272 } 1273 } 1274 1275 return SECCLASS_SOCKET; 1276 } 1277 1278 static int selinux_genfs_get_sid(struct dentry *dentry, 1279 u16 tclass, 1280 u16 flags, 1281 u32 *sid) 1282 { 1283 int rc; 1284 struct super_block *sb = dentry->d_sb; 1285 char *buffer, *path; 1286 1287 buffer = (char *)__get_free_page(GFP_KERNEL); 1288 if (!buffer) 1289 return -ENOMEM; 1290 1291 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1292 if (IS_ERR(path)) 1293 rc = PTR_ERR(path); 1294 else { 1295 if (flags & SE_SBPROC) { 1296 /* each process gets a /proc/PID/ entry. Strip off the 1297 * PID part to get a valid selinux labeling. 1298 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1299 while (path[1] >= '0' && path[1] <= '9') { 1300 path[1] = '/'; 1301 path++; 1302 } 1303 } 1304 rc = security_genfs_sid(&selinux_state, sb->s_type->name, 1305 path, tclass, sid); 1306 if (rc == -ENOENT) { 1307 /* No match in policy, mark as unlabeled. */ 1308 *sid = SECINITSID_UNLABELED; 1309 rc = 0; 1310 } 1311 } 1312 free_page((unsigned long)buffer); 1313 return rc; 1314 } 1315 1316 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1317 u32 def_sid, u32 *sid) 1318 { 1319 #define INITCONTEXTLEN 255 1320 char *context; 1321 unsigned int len; 1322 int rc; 1323 1324 len = INITCONTEXTLEN; 1325 context = kmalloc(len + 1, GFP_NOFS); 1326 if (!context) 1327 return -ENOMEM; 1328 1329 context[len] = '\0'; 1330 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1331 if (rc == -ERANGE) { 1332 kfree(context); 1333 1334 /* Need a larger buffer. Query for the right size. */ 1335 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1336 if (rc < 0) 1337 return rc; 1338 1339 len = rc; 1340 context = kmalloc(len + 1, GFP_NOFS); 1341 if (!context) 1342 return -ENOMEM; 1343 1344 context[len] = '\0'; 1345 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1346 context, len); 1347 } 1348 if (rc < 0) { 1349 kfree(context); 1350 if (rc != -ENODATA) { 1351 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1352 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1353 return rc; 1354 } 1355 *sid = def_sid; 1356 return 0; 1357 } 1358 1359 rc = security_context_to_sid_default(&selinux_state, context, rc, sid, 1360 def_sid, GFP_NOFS); 1361 if (rc) { 1362 char *dev = inode->i_sb->s_id; 1363 unsigned long ino = inode->i_ino; 1364 1365 if (rc == -EINVAL) { 1366 pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s. This indicates you may need to relabel the inode or the filesystem in question.\n", 1367 ino, dev, context); 1368 } else { 1369 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1370 __func__, context, -rc, dev, ino); 1371 } 1372 } 1373 kfree(context); 1374 return 0; 1375 } 1376 1377 /* The inode's security attributes must be initialized before first use. */ 1378 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1379 { 1380 struct superblock_security_struct *sbsec = NULL; 1381 struct inode_security_struct *isec = selinux_inode(inode); 1382 u32 task_sid, sid = 0; 1383 u16 sclass; 1384 struct dentry *dentry; 1385 int rc = 0; 1386 1387 if (isec->initialized == LABEL_INITIALIZED) 1388 return 0; 1389 1390 spin_lock(&isec->lock); 1391 if (isec->initialized == LABEL_INITIALIZED) 1392 goto out_unlock; 1393 1394 if (isec->sclass == SECCLASS_FILE) 1395 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1396 1397 sbsec = inode->i_sb->s_security; 1398 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1399 /* Defer initialization until selinux_complete_init, 1400 after the initial policy is loaded and the security 1401 server is ready to handle calls. */ 1402 spin_lock(&sbsec->isec_lock); 1403 if (list_empty(&isec->list)) 1404 list_add(&isec->list, &sbsec->isec_head); 1405 spin_unlock(&sbsec->isec_lock); 1406 goto out_unlock; 1407 } 1408 1409 sclass = isec->sclass; 1410 task_sid = isec->task_sid; 1411 sid = isec->sid; 1412 isec->initialized = LABEL_PENDING; 1413 spin_unlock(&isec->lock); 1414 1415 switch (sbsec->behavior) { 1416 case SECURITY_FS_USE_NATIVE: 1417 break; 1418 case SECURITY_FS_USE_XATTR: 1419 if (!(inode->i_opflags & IOP_XATTR)) { 1420 sid = sbsec->def_sid; 1421 break; 1422 } 1423 /* Need a dentry, since the xattr API requires one. 1424 Life would be simpler if we could just pass the inode. */ 1425 if (opt_dentry) { 1426 /* Called from d_instantiate or d_splice_alias. */ 1427 dentry = dget(opt_dentry); 1428 } else { 1429 /* 1430 * Called from selinux_complete_init, try to find a dentry. 1431 * Some filesystems really want a connected one, so try 1432 * that first. We could split SECURITY_FS_USE_XATTR in 1433 * two, depending upon that... 1434 */ 1435 dentry = d_find_alias(inode); 1436 if (!dentry) 1437 dentry = d_find_any_alias(inode); 1438 } 1439 if (!dentry) { 1440 /* 1441 * this is can be hit on boot when a file is accessed 1442 * before the policy is loaded. When we load policy we 1443 * may find inodes that have no dentry on the 1444 * sbsec->isec_head list. No reason to complain as these 1445 * will get fixed up the next time we go through 1446 * inode_doinit with a dentry, before these inodes could 1447 * be used again by userspace. 1448 */ 1449 goto out; 1450 } 1451 1452 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1453 &sid); 1454 dput(dentry); 1455 if (rc) 1456 goto out; 1457 break; 1458 case SECURITY_FS_USE_TASK: 1459 sid = task_sid; 1460 break; 1461 case SECURITY_FS_USE_TRANS: 1462 /* Default to the fs SID. */ 1463 sid = sbsec->sid; 1464 1465 /* Try to obtain a transition SID. */ 1466 rc = security_transition_sid(&selinux_state, task_sid, sid, 1467 sclass, NULL, &sid); 1468 if (rc) 1469 goto out; 1470 break; 1471 case SECURITY_FS_USE_MNTPOINT: 1472 sid = sbsec->mntpoint_sid; 1473 break; 1474 default: 1475 /* Default to the fs superblock SID. */ 1476 sid = sbsec->sid; 1477 1478 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { 1479 /* We must have a dentry to determine the label on 1480 * procfs inodes */ 1481 if (opt_dentry) { 1482 /* Called from d_instantiate or 1483 * d_splice_alias. */ 1484 dentry = dget(opt_dentry); 1485 } else { 1486 /* Called from selinux_complete_init, try to 1487 * find a dentry. Some filesystems really want 1488 * a connected one, so try that first. 1489 */ 1490 dentry = d_find_alias(inode); 1491 if (!dentry) 1492 dentry = d_find_any_alias(inode); 1493 } 1494 /* 1495 * This can be hit on boot when a file is accessed 1496 * before the policy is loaded. When we load policy we 1497 * may find inodes that have no dentry on the 1498 * sbsec->isec_head list. No reason to complain as 1499 * these will get fixed up the next time we go through 1500 * inode_doinit() with a dentry, before these inodes 1501 * could be used again by userspace. 1502 */ 1503 if (!dentry) 1504 goto out; 1505 rc = selinux_genfs_get_sid(dentry, sclass, 1506 sbsec->flags, &sid); 1507 if (rc) { 1508 dput(dentry); 1509 goto out; 1510 } 1511 1512 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1513 (inode->i_opflags & IOP_XATTR)) { 1514 rc = inode_doinit_use_xattr(inode, dentry, 1515 sid, &sid); 1516 if (rc) { 1517 dput(dentry); 1518 goto out; 1519 } 1520 } 1521 dput(dentry); 1522 } 1523 break; 1524 } 1525 1526 out: 1527 spin_lock(&isec->lock); 1528 if (isec->initialized == LABEL_PENDING) { 1529 if (!sid || rc) { 1530 isec->initialized = LABEL_INVALID; 1531 goto out_unlock; 1532 } 1533 1534 isec->initialized = LABEL_INITIALIZED; 1535 isec->sid = sid; 1536 } 1537 1538 out_unlock: 1539 spin_unlock(&isec->lock); 1540 return rc; 1541 } 1542 1543 /* Convert a Linux signal to an access vector. */ 1544 static inline u32 signal_to_av(int sig) 1545 { 1546 u32 perm = 0; 1547 1548 switch (sig) { 1549 case SIGCHLD: 1550 /* Commonly granted from child to parent. */ 1551 perm = PROCESS__SIGCHLD; 1552 break; 1553 case SIGKILL: 1554 /* Cannot be caught or ignored */ 1555 perm = PROCESS__SIGKILL; 1556 break; 1557 case SIGSTOP: 1558 /* Cannot be caught or ignored */ 1559 perm = PROCESS__SIGSTOP; 1560 break; 1561 default: 1562 /* All other signals. */ 1563 perm = PROCESS__SIGNAL; 1564 break; 1565 } 1566 1567 return perm; 1568 } 1569 1570 #if CAP_LAST_CAP > 63 1571 #error Fix SELinux to handle capabilities > 63. 1572 #endif 1573 1574 /* Check whether a task is allowed to use a capability. */ 1575 static int cred_has_capability(const struct cred *cred, 1576 int cap, unsigned int opts, bool initns) 1577 { 1578 struct common_audit_data ad; 1579 struct av_decision avd; 1580 u16 sclass; 1581 u32 sid = cred_sid(cred); 1582 u32 av = CAP_TO_MASK(cap); 1583 int rc; 1584 1585 ad.type = LSM_AUDIT_DATA_CAP; 1586 ad.u.cap = cap; 1587 1588 switch (CAP_TO_INDEX(cap)) { 1589 case 0: 1590 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1591 break; 1592 case 1: 1593 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1594 break; 1595 default: 1596 pr_err("SELinux: out of range capability %d\n", cap); 1597 BUG(); 1598 return -EINVAL; 1599 } 1600 1601 rc = avc_has_perm_noaudit(&selinux_state, 1602 sid, sid, sclass, av, 0, &avd); 1603 if (!(opts & CAP_OPT_NOAUDIT)) { 1604 int rc2 = avc_audit(&selinux_state, 1605 sid, sid, sclass, av, &avd, rc, &ad, 0); 1606 if (rc2) 1607 return rc2; 1608 } 1609 return rc; 1610 } 1611 1612 /* Check whether a task has a particular permission to an inode. 1613 The 'adp' parameter is optional and allows other audit 1614 data to be passed (e.g. the dentry). */ 1615 static int inode_has_perm(const struct cred *cred, 1616 struct inode *inode, 1617 u32 perms, 1618 struct common_audit_data *adp) 1619 { 1620 struct inode_security_struct *isec; 1621 u32 sid; 1622 1623 validate_creds(cred); 1624 1625 if (unlikely(IS_PRIVATE(inode))) 1626 return 0; 1627 1628 sid = cred_sid(cred); 1629 isec = selinux_inode(inode); 1630 1631 return avc_has_perm(&selinux_state, 1632 sid, isec->sid, isec->sclass, perms, adp); 1633 } 1634 1635 /* Same as inode_has_perm, but pass explicit audit data containing 1636 the dentry to help the auditing code to more easily generate the 1637 pathname if needed. */ 1638 static inline int dentry_has_perm(const struct cred *cred, 1639 struct dentry *dentry, 1640 u32 av) 1641 { 1642 struct inode *inode = d_backing_inode(dentry); 1643 struct common_audit_data ad; 1644 1645 ad.type = LSM_AUDIT_DATA_DENTRY; 1646 ad.u.dentry = dentry; 1647 __inode_security_revalidate(inode, dentry, true); 1648 return inode_has_perm(cred, inode, av, &ad); 1649 } 1650 1651 /* Same as inode_has_perm, but pass explicit audit data containing 1652 the path to help the auditing code to more easily generate the 1653 pathname if needed. */ 1654 static inline int path_has_perm(const struct cred *cred, 1655 const struct path *path, 1656 u32 av) 1657 { 1658 struct inode *inode = d_backing_inode(path->dentry); 1659 struct common_audit_data ad; 1660 1661 ad.type = LSM_AUDIT_DATA_PATH; 1662 ad.u.path = *path; 1663 __inode_security_revalidate(inode, path->dentry, true); 1664 return inode_has_perm(cred, inode, av, &ad); 1665 } 1666 1667 /* Same as path_has_perm, but uses the inode from the file struct. */ 1668 static inline int file_path_has_perm(const struct cred *cred, 1669 struct file *file, 1670 u32 av) 1671 { 1672 struct common_audit_data ad; 1673 1674 ad.type = LSM_AUDIT_DATA_FILE; 1675 ad.u.file = file; 1676 return inode_has_perm(cred, file_inode(file), av, &ad); 1677 } 1678 1679 #ifdef CONFIG_BPF_SYSCALL 1680 static int bpf_fd_pass(struct file *file, u32 sid); 1681 #endif 1682 1683 /* Check whether a task can use an open file descriptor to 1684 access an inode in a given way. Check access to the 1685 descriptor itself, and then use dentry_has_perm to 1686 check a particular permission to the file. 1687 Access to the descriptor is implicitly granted if it 1688 has the same SID as the process. If av is zero, then 1689 access to the file is not checked, e.g. for cases 1690 where only the descriptor is affected like seek. */ 1691 static int file_has_perm(const struct cred *cred, 1692 struct file *file, 1693 u32 av) 1694 { 1695 struct file_security_struct *fsec = selinux_file(file); 1696 struct inode *inode = file_inode(file); 1697 struct common_audit_data ad; 1698 u32 sid = cred_sid(cred); 1699 int rc; 1700 1701 ad.type = LSM_AUDIT_DATA_FILE; 1702 ad.u.file = file; 1703 1704 if (sid != fsec->sid) { 1705 rc = avc_has_perm(&selinux_state, 1706 sid, fsec->sid, 1707 SECCLASS_FD, 1708 FD__USE, 1709 &ad); 1710 if (rc) 1711 goto out; 1712 } 1713 1714 #ifdef CONFIG_BPF_SYSCALL 1715 rc = bpf_fd_pass(file, cred_sid(cred)); 1716 if (rc) 1717 return rc; 1718 #endif 1719 1720 /* av is zero if only checking access to the descriptor. */ 1721 rc = 0; 1722 if (av) 1723 rc = inode_has_perm(cred, inode, av, &ad); 1724 1725 out: 1726 return rc; 1727 } 1728 1729 /* 1730 * Determine the label for an inode that might be unioned. 1731 */ 1732 static int 1733 selinux_determine_inode_label(const struct task_security_struct *tsec, 1734 struct inode *dir, 1735 const struct qstr *name, u16 tclass, 1736 u32 *_new_isid) 1737 { 1738 const struct superblock_security_struct *sbsec = dir->i_sb->s_security; 1739 1740 if ((sbsec->flags & SE_SBINITIALIZED) && 1741 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1742 *_new_isid = sbsec->mntpoint_sid; 1743 } else if ((sbsec->flags & SBLABEL_MNT) && 1744 tsec->create_sid) { 1745 *_new_isid = tsec->create_sid; 1746 } else { 1747 const struct inode_security_struct *dsec = inode_security(dir); 1748 return security_transition_sid(&selinux_state, tsec->sid, 1749 dsec->sid, tclass, 1750 name, _new_isid); 1751 } 1752 1753 return 0; 1754 } 1755 1756 /* Check whether a task can create a file. */ 1757 static int may_create(struct inode *dir, 1758 struct dentry *dentry, 1759 u16 tclass) 1760 { 1761 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1762 struct inode_security_struct *dsec; 1763 struct superblock_security_struct *sbsec; 1764 u32 sid, newsid; 1765 struct common_audit_data ad; 1766 int rc; 1767 1768 dsec = inode_security(dir); 1769 sbsec = dir->i_sb->s_security; 1770 1771 sid = tsec->sid; 1772 1773 ad.type = LSM_AUDIT_DATA_DENTRY; 1774 ad.u.dentry = dentry; 1775 1776 rc = avc_has_perm(&selinux_state, 1777 sid, dsec->sid, SECCLASS_DIR, 1778 DIR__ADD_NAME | DIR__SEARCH, 1779 &ad); 1780 if (rc) 1781 return rc; 1782 1783 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1784 &newsid); 1785 if (rc) 1786 return rc; 1787 1788 rc = avc_has_perm(&selinux_state, 1789 sid, newsid, tclass, FILE__CREATE, &ad); 1790 if (rc) 1791 return rc; 1792 1793 return avc_has_perm(&selinux_state, 1794 newsid, sbsec->sid, 1795 SECCLASS_FILESYSTEM, 1796 FILESYSTEM__ASSOCIATE, &ad); 1797 } 1798 1799 #define MAY_LINK 0 1800 #define MAY_UNLINK 1 1801 #define MAY_RMDIR 2 1802 1803 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1804 static int may_link(struct inode *dir, 1805 struct dentry *dentry, 1806 int kind) 1807 1808 { 1809 struct inode_security_struct *dsec, *isec; 1810 struct common_audit_data ad; 1811 u32 sid = current_sid(); 1812 u32 av; 1813 int rc; 1814 1815 dsec = inode_security(dir); 1816 isec = backing_inode_security(dentry); 1817 1818 ad.type = LSM_AUDIT_DATA_DENTRY; 1819 ad.u.dentry = dentry; 1820 1821 av = DIR__SEARCH; 1822 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1823 rc = avc_has_perm(&selinux_state, 1824 sid, dsec->sid, SECCLASS_DIR, av, &ad); 1825 if (rc) 1826 return rc; 1827 1828 switch (kind) { 1829 case MAY_LINK: 1830 av = FILE__LINK; 1831 break; 1832 case MAY_UNLINK: 1833 av = FILE__UNLINK; 1834 break; 1835 case MAY_RMDIR: 1836 av = DIR__RMDIR; 1837 break; 1838 default: 1839 pr_warn("SELinux: %s: unrecognized kind %d\n", 1840 __func__, kind); 1841 return 0; 1842 } 1843 1844 rc = avc_has_perm(&selinux_state, 1845 sid, isec->sid, isec->sclass, av, &ad); 1846 return rc; 1847 } 1848 1849 static inline int may_rename(struct inode *old_dir, 1850 struct dentry *old_dentry, 1851 struct inode *new_dir, 1852 struct dentry *new_dentry) 1853 { 1854 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1855 struct common_audit_data ad; 1856 u32 sid = current_sid(); 1857 u32 av; 1858 int old_is_dir, new_is_dir; 1859 int rc; 1860 1861 old_dsec = inode_security(old_dir); 1862 old_isec = backing_inode_security(old_dentry); 1863 old_is_dir = d_is_dir(old_dentry); 1864 new_dsec = inode_security(new_dir); 1865 1866 ad.type = LSM_AUDIT_DATA_DENTRY; 1867 1868 ad.u.dentry = old_dentry; 1869 rc = avc_has_perm(&selinux_state, 1870 sid, old_dsec->sid, SECCLASS_DIR, 1871 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1872 if (rc) 1873 return rc; 1874 rc = avc_has_perm(&selinux_state, 1875 sid, old_isec->sid, 1876 old_isec->sclass, FILE__RENAME, &ad); 1877 if (rc) 1878 return rc; 1879 if (old_is_dir && new_dir != old_dir) { 1880 rc = avc_has_perm(&selinux_state, 1881 sid, old_isec->sid, 1882 old_isec->sclass, DIR__REPARENT, &ad); 1883 if (rc) 1884 return rc; 1885 } 1886 1887 ad.u.dentry = new_dentry; 1888 av = DIR__ADD_NAME | DIR__SEARCH; 1889 if (d_is_positive(new_dentry)) 1890 av |= DIR__REMOVE_NAME; 1891 rc = avc_has_perm(&selinux_state, 1892 sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1893 if (rc) 1894 return rc; 1895 if (d_is_positive(new_dentry)) { 1896 new_isec = backing_inode_security(new_dentry); 1897 new_is_dir = d_is_dir(new_dentry); 1898 rc = avc_has_perm(&selinux_state, 1899 sid, new_isec->sid, 1900 new_isec->sclass, 1901 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1902 if (rc) 1903 return rc; 1904 } 1905 1906 return 0; 1907 } 1908 1909 /* Check whether a task can perform a filesystem operation. */ 1910 static int superblock_has_perm(const struct cred *cred, 1911 struct super_block *sb, 1912 u32 perms, 1913 struct common_audit_data *ad) 1914 { 1915 struct superblock_security_struct *sbsec; 1916 u32 sid = cred_sid(cred); 1917 1918 sbsec = sb->s_security; 1919 return avc_has_perm(&selinux_state, 1920 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1921 } 1922 1923 /* Convert a Linux mode and permission mask to an access vector. */ 1924 static inline u32 file_mask_to_av(int mode, int mask) 1925 { 1926 u32 av = 0; 1927 1928 if (!S_ISDIR(mode)) { 1929 if (mask & MAY_EXEC) 1930 av |= FILE__EXECUTE; 1931 if (mask & MAY_READ) 1932 av |= FILE__READ; 1933 1934 if (mask & MAY_APPEND) 1935 av |= FILE__APPEND; 1936 else if (mask & MAY_WRITE) 1937 av |= FILE__WRITE; 1938 1939 } else { 1940 if (mask & MAY_EXEC) 1941 av |= DIR__SEARCH; 1942 if (mask & MAY_WRITE) 1943 av |= DIR__WRITE; 1944 if (mask & MAY_READ) 1945 av |= DIR__READ; 1946 } 1947 1948 return av; 1949 } 1950 1951 /* Convert a Linux file to an access vector. */ 1952 static inline u32 file_to_av(struct file *file) 1953 { 1954 u32 av = 0; 1955 1956 if (file->f_mode & FMODE_READ) 1957 av |= FILE__READ; 1958 if (file->f_mode & FMODE_WRITE) { 1959 if (file->f_flags & O_APPEND) 1960 av |= FILE__APPEND; 1961 else 1962 av |= FILE__WRITE; 1963 } 1964 if (!av) { 1965 /* 1966 * Special file opened with flags 3 for ioctl-only use. 1967 */ 1968 av = FILE__IOCTL; 1969 } 1970 1971 return av; 1972 } 1973 1974 /* 1975 * Convert a file to an access vector and include the correct open 1976 * open permission. 1977 */ 1978 static inline u32 open_file_to_av(struct file *file) 1979 { 1980 u32 av = file_to_av(file); 1981 struct inode *inode = file_inode(file); 1982 1983 if (selinux_policycap_openperm() && 1984 inode->i_sb->s_magic != SOCKFS_MAGIC) 1985 av |= FILE__OPEN; 1986 1987 return av; 1988 } 1989 1990 /* Hook functions begin here. */ 1991 1992 static int selinux_binder_set_context_mgr(struct task_struct *mgr) 1993 { 1994 u32 mysid = current_sid(); 1995 u32 mgrsid = task_sid(mgr); 1996 1997 return avc_has_perm(&selinux_state, 1998 mysid, mgrsid, SECCLASS_BINDER, 1999 BINDER__SET_CONTEXT_MGR, NULL); 2000 } 2001 2002 static int selinux_binder_transaction(struct task_struct *from, 2003 struct task_struct *to) 2004 { 2005 u32 mysid = current_sid(); 2006 u32 fromsid = task_sid(from); 2007 u32 tosid = task_sid(to); 2008 int rc; 2009 2010 if (mysid != fromsid) { 2011 rc = avc_has_perm(&selinux_state, 2012 mysid, fromsid, SECCLASS_BINDER, 2013 BINDER__IMPERSONATE, NULL); 2014 if (rc) 2015 return rc; 2016 } 2017 2018 return avc_has_perm(&selinux_state, 2019 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, 2020 NULL); 2021 } 2022 2023 static int selinux_binder_transfer_binder(struct task_struct *from, 2024 struct task_struct *to) 2025 { 2026 u32 fromsid = task_sid(from); 2027 u32 tosid = task_sid(to); 2028 2029 return avc_has_perm(&selinux_state, 2030 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, 2031 NULL); 2032 } 2033 2034 static int selinux_binder_transfer_file(struct task_struct *from, 2035 struct task_struct *to, 2036 struct file *file) 2037 { 2038 u32 sid = task_sid(to); 2039 struct file_security_struct *fsec = selinux_file(file); 2040 struct dentry *dentry = file->f_path.dentry; 2041 struct inode_security_struct *isec; 2042 struct common_audit_data ad; 2043 int rc; 2044 2045 ad.type = LSM_AUDIT_DATA_PATH; 2046 ad.u.path = file->f_path; 2047 2048 if (sid != fsec->sid) { 2049 rc = avc_has_perm(&selinux_state, 2050 sid, fsec->sid, 2051 SECCLASS_FD, 2052 FD__USE, 2053 &ad); 2054 if (rc) 2055 return rc; 2056 } 2057 2058 #ifdef CONFIG_BPF_SYSCALL 2059 rc = bpf_fd_pass(file, sid); 2060 if (rc) 2061 return rc; 2062 #endif 2063 2064 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2065 return 0; 2066 2067 isec = backing_inode_security(dentry); 2068 return avc_has_perm(&selinux_state, 2069 sid, isec->sid, isec->sclass, file_to_av(file), 2070 &ad); 2071 } 2072 2073 static int selinux_ptrace_access_check(struct task_struct *child, 2074 unsigned int mode) 2075 { 2076 u32 sid = current_sid(); 2077 u32 csid = task_sid(child); 2078 2079 if (mode & PTRACE_MODE_READ) 2080 return avc_has_perm(&selinux_state, 2081 sid, csid, SECCLASS_FILE, FILE__READ, NULL); 2082 2083 return avc_has_perm(&selinux_state, 2084 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2085 } 2086 2087 static int selinux_ptrace_traceme(struct task_struct *parent) 2088 { 2089 return avc_has_perm(&selinux_state, 2090 task_sid(parent), current_sid(), SECCLASS_PROCESS, 2091 PROCESS__PTRACE, NULL); 2092 } 2093 2094 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 2095 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2096 { 2097 return avc_has_perm(&selinux_state, 2098 current_sid(), task_sid(target), SECCLASS_PROCESS, 2099 PROCESS__GETCAP, NULL); 2100 } 2101 2102 static int selinux_capset(struct cred *new, const struct cred *old, 2103 const kernel_cap_t *effective, 2104 const kernel_cap_t *inheritable, 2105 const kernel_cap_t *permitted) 2106 { 2107 return avc_has_perm(&selinux_state, 2108 cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2109 PROCESS__SETCAP, NULL); 2110 } 2111 2112 /* 2113 * (This comment used to live with the selinux_task_setuid hook, 2114 * which was removed). 2115 * 2116 * Since setuid only affects the current process, and since the SELinux 2117 * controls are not based on the Linux identity attributes, SELinux does not 2118 * need to control this operation. However, SELinux does control the use of 2119 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2120 */ 2121 2122 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2123 int cap, unsigned int opts) 2124 { 2125 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2126 } 2127 2128 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2129 { 2130 const struct cred *cred = current_cred(); 2131 int rc = 0; 2132 2133 if (!sb) 2134 return 0; 2135 2136 switch (cmds) { 2137 case Q_SYNC: 2138 case Q_QUOTAON: 2139 case Q_QUOTAOFF: 2140 case Q_SETINFO: 2141 case Q_SETQUOTA: 2142 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2143 break; 2144 case Q_GETFMT: 2145 case Q_GETINFO: 2146 case Q_GETQUOTA: 2147 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2148 break; 2149 default: 2150 rc = 0; /* let the kernel handle invalid cmds */ 2151 break; 2152 } 2153 return rc; 2154 } 2155 2156 static int selinux_quota_on(struct dentry *dentry) 2157 { 2158 const struct cred *cred = current_cred(); 2159 2160 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2161 } 2162 2163 static int selinux_syslog(int type) 2164 { 2165 switch (type) { 2166 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2167 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2168 return avc_has_perm(&selinux_state, 2169 current_sid(), SECINITSID_KERNEL, 2170 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2171 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2172 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2173 /* Set level of messages printed to console */ 2174 case SYSLOG_ACTION_CONSOLE_LEVEL: 2175 return avc_has_perm(&selinux_state, 2176 current_sid(), SECINITSID_KERNEL, 2177 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2178 NULL); 2179 } 2180 /* All other syslog types */ 2181 return avc_has_perm(&selinux_state, 2182 current_sid(), SECINITSID_KERNEL, 2183 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2184 } 2185 2186 /* 2187 * Check that a process has enough memory to allocate a new virtual 2188 * mapping. 0 means there is enough memory for the allocation to 2189 * succeed and -ENOMEM implies there is not. 2190 * 2191 * Do not audit the selinux permission check, as this is applied to all 2192 * processes that allocate mappings. 2193 */ 2194 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2195 { 2196 int rc, cap_sys_admin = 0; 2197 2198 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2199 CAP_OPT_NOAUDIT, true); 2200 if (rc == 0) 2201 cap_sys_admin = 1; 2202 2203 return cap_sys_admin; 2204 } 2205 2206 /* binprm security operations */ 2207 2208 static u32 ptrace_parent_sid(void) 2209 { 2210 u32 sid = 0; 2211 struct task_struct *tracer; 2212 2213 rcu_read_lock(); 2214 tracer = ptrace_parent(current); 2215 if (tracer) 2216 sid = task_sid(tracer); 2217 rcu_read_unlock(); 2218 2219 return sid; 2220 } 2221 2222 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2223 const struct task_security_struct *old_tsec, 2224 const struct task_security_struct *new_tsec) 2225 { 2226 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2227 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2228 int rc; 2229 u32 av; 2230 2231 if (!nnp && !nosuid) 2232 return 0; /* neither NNP nor nosuid */ 2233 2234 if (new_tsec->sid == old_tsec->sid) 2235 return 0; /* No change in credentials */ 2236 2237 /* 2238 * If the policy enables the nnp_nosuid_transition policy capability, 2239 * then we permit transitions under NNP or nosuid if the 2240 * policy allows the corresponding permission between 2241 * the old and new contexts. 2242 */ 2243 if (selinux_policycap_nnp_nosuid_transition()) { 2244 av = 0; 2245 if (nnp) 2246 av |= PROCESS2__NNP_TRANSITION; 2247 if (nosuid) 2248 av |= PROCESS2__NOSUID_TRANSITION; 2249 rc = avc_has_perm(&selinux_state, 2250 old_tsec->sid, new_tsec->sid, 2251 SECCLASS_PROCESS2, av, NULL); 2252 if (!rc) 2253 return 0; 2254 } 2255 2256 /* 2257 * We also permit NNP or nosuid transitions to bounded SIDs, 2258 * i.e. SIDs that are guaranteed to only be allowed a subset 2259 * of the permissions of the current SID. 2260 */ 2261 rc = security_bounded_transition(&selinux_state, old_tsec->sid, 2262 new_tsec->sid); 2263 if (!rc) 2264 return 0; 2265 2266 /* 2267 * On failure, preserve the errno values for NNP vs nosuid. 2268 * NNP: Operation not permitted for caller. 2269 * nosuid: Permission denied to file. 2270 */ 2271 if (nnp) 2272 return -EPERM; 2273 return -EACCES; 2274 } 2275 2276 static int selinux_bprm_set_creds(struct linux_binprm *bprm) 2277 { 2278 const struct task_security_struct *old_tsec; 2279 struct task_security_struct *new_tsec; 2280 struct inode_security_struct *isec; 2281 struct common_audit_data ad; 2282 struct inode *inode = file_inode(bprm->file); 2283 int rc; 2284 2285 /* SELinux context only depends on initial program or script and not 2286 * the script interpreter */ 2287 if (bprm->called_set_creds) 2288 return 0; 2289 2290 old_tsec = selinux_cred(current_cred()); 2291 new_tsec = selinux_cred(bprm->cred); 2292 isec = inode_security(inode); 2293 2294 /* Default to the current task SID. */ 2295 new_tsec->sid = old_tsec->sid; 2296 new_tsec->osid = old_tsec->sid; 2297 2298 /* Reset fs, key, and sock SIDs on execve. */ 2299 new_tsec->create_sid = 0; 2300 new_tsec->keycreate_sid = 0; 2301 new_tsec->sockcreate_sid = 0; 2302 2303 if (old_tsec->exec_sid) { 2304 new_tsec->sid = old_tsec->exec_sid; 2305 /* Reset exec SID on execve. */ 2306 new_tsec->exec_sid = 0; 2307 2308 /* Fail on NNP or nosuid if not an allowed transition. */ 2309 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2310 if (rc) 2311 return rc; 2312 } else { 2313 /* Check for a default transition on this program. */ 2314 rc = security_transition_sid(&selinux_state, old_tsec->sid, 2315 isec->sid, SECCLASS_PROCESS, NULL, 2316 &new_tsec->sid); 2317 if (rc) 2318 return rc; 2319 2320 /* 2321 * Fallback to old SID on NNP or nosuid if not an allowed 2322 * transition. 2323 */ 2324 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2325 if (rc) 2326 new_tsec->sid = old_tsec->sid; 2327 } 2328 2329 ad.type = LSM_AUDIT_DATA_FILE; 2330 ad.u.file = bprm->file; 2331 2332 if (new_tsec->sid == old_tsec->sid) { 2333 rc = avc_has_perm(&selinux_state, 2334 old_tsec->sid, isec->sid, 2335 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2336 if (rc) 2337 return rc; 2338 } else { 2339 /* Check permissions for the transition. */ 2340 rc = avc_has_perm(&selinux_state, 2341 old_tsec->sid, new_tsec->sid, 2342 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2343 if (rc) 2344 return rc; 2345 2346 rc = avc_has_perm(&selinux_state, 2347 new_tsec->sid, isec->sid, 2348 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2349 if (rc) 2350 return rc; 2351 2352 /* Check for shared state */ 2353 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2354 rc = avc_has_perm(&selinux_state, 2355 old_tsec->sid, new_tsec->sid, 2356 SECCLASS_PROCESS, PROCESS__SHARE, 2357 NULL); 2358 if (rc) 2359 return -EPERM; 2360 } 2361 2362 /* Make sure that anyone attempting to ptrace over a task that 2363 * changes its SID has the appropriate permit */ 2364 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2365 u32 ptsid = ptrace_parent_sid(); 2366 if (ptsid != 0) { 2367 rc = avc_has_perm(&selinux_state, 2368 ptsid, new_tsec->sid, 2369 SECCLASS_PROCESS, 2370 PROCESS__PTRACE, NULL); 2371 if (rc) 2372 return -EPERM; 2373 } 2374 } 2375 2376 /* Clear any possibly unsafe personality bits on exec: */ 2377 bprm->per_clear |= PER_CLEAR_ON_SETID; 2378 2379 /* Enable secure mode for SIDs transitions unless 2380 the noatsecure permission is granted between 2381 the two SIDs, i.e. ahp returns 0. */ 2382 rc = avc_has_perm(&selinux_state, 2383 old_tsec->sid, new_tsec->sid, 2384 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2385 NULL); 2386 bprm->secureexec |= !!rc; 2387 } 2388 2389 return 0; 2390 } 2391 2392 static int match_file(const void *p, struct file *file, unsigned fd) 2393 { 2394 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2395 } 2396 2397 /* Derived from fs/exec.c:flush_old_files. */ 2398 static inline void flush_unauthorized_files(const struct cred *cred, 2399 struct files_struct *files) 2400 { 2401 struct file *file, *devnull = NULL; 2402 struct tty_struct *tty; 2403 int drop_tty = 0; 2404 unsigned n; 2405 2406 tty = get_current_tty(); 2407 if (tty) { 2408 spin_lock(&tty->files_lock); 2409 if (!list_empty(&tty->tty_files)) { 2410 struct tty_file_private *file_priv; 2411 2412 /* Revalidate access to controlling tty. 2413 Use file_path_has_perm on the tty path directly 2414 rather than using file_has_perm, as this particular 2415 open file may belong to another process and we are 2416 only interested in the inode-based check here. */ 2417 file_priv = list_first_entry(&tty->tty_files, 2418 struct tty_file_private, list); 2419 file = file_priv->file; 2420 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2421 drop_tty = 1; 2422 } 2423 spin_unlock(&tty->files_lock); 2424 tty_kref_put(tty); 2425 } 2426 /* Reset controlling tty. */ 2427 if (drop_tty) 2428 no_tty(); 2429 2430 /* Revalidate access to inherited open files. */ 2431 n = iterate_fd(files, 0, match_file, cred); 2432 if (!n) /* none found? */ 2433 return; 2434 2435 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2436 if (IS_ERR(devnull)) 2437 devnull = NULL; 2438 /* replace all the matching ones with this */ 2439 do { 2440 replace_fd(n - 1, devnull, 0); 2441 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2442 if (devnull) 2443 fput(devnull); 2444 } 2445 2446 /* 2447 * Prepare a process for imminent new credential changes due to exec 2448 */ 2449 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2450 { 2451 struct task_security_struct *new_tsec; 2452 struct rlimit *rlim, *initrlim; 2453 int rc, i; 2454 2455 new_tsec = selinux_cred(bprm->cred); 2456 if (new_tsec->sid == new_tsec->osid) 2457 return; 2458 2459 /* Close files for which the new task SID is not authorized. */ 2460 flush_unauthorized_files(bprm->cred, current->files); 2461 2462 /* Always clear parent death signal on SID transitions. */ 2463 current->pdeath_signal = 0; 2464 2465 /* Check whether the new SID can inherit resource limits from the old 2466 * SID. If not, reset all soft limits to the lower of the current 2467 * task's hard limit and the init task's soft limit. 2468 * 2469 * Note that the setting of hard limits (even to lower them) can be 2470 * controlled by the setrlimit check. The inclusion of the init task's 2471 * soft limit into the computation is to avoid resetting soft limits 2472 * higher than the default soft limit for cases where the default is 2473 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2474 */ 2475 rc = avc_has_perm(&selinux_state, 2476 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2477 PROCESS__RLIMITINH, NULL); 2478 if (rc) { 2479 /* protect against do_prlimit() */ 2480 task_lock(current); 2481 for (i = 0; i < RLIM_NLIMITS; i++) { 2482 rlim = current->signal->rlim + i; 2483 initrlim = init_task.signal->rlim + i; 2484 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2485 } 2486 task_unlock(current); 2487 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2488 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2489 } 2490 } 2491 2492 /* 2493 * Clean up the process immediately after the installation of new credentials 2494 * due to exec 2495 */ 2496 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2497 { 2498 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2499 u32 osid, sid; 2500 int rc; 2501 2502 osid = tsec->osid; 2503 sid = tsec->sid; 2504 2505 if (sid == osid) 2506 return; 2507 2508 /* Check whether the new SID can inherit signal state from the old SID. 2509 * If not, clear itimers to avoid subsequent signal generation and 2510 * flush and unblock signals. 2511 * 2512 * This must occur _after_ the task SID has been updated so that any 2513 * kill done after the flush will be checked against the new SID. 2514 */ 2515 rc = avc_has_perm(&selinux_state, 2516 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2517 if (rc) { 2518 clear_itimer(); 2519 2520 spin_lock_irq(¤t->sighand->siglock); 2521 if (!fatal_signal_pending(current)) { 2522 flush_sigqueue(¤t->pending); 2523 flush_sigqueue(¤t->signal->shared_pending); 2524 flush_signal_handlers(current, 1); 2525 sigemptyset(¤t->blocked); 2526 recalc_sigpending(); 2527 } 2528 spin_unlock_irq(¤t->sighand->siglock); 2529 } 2530 2531 /* Wake up the parent if it is waiting so that it can recheck 2532 * wait permission to the new task SID. */ 2533 read_lock(&tasklist_lock); 2534 __wake_up_parent(current, current->real_parent); 2535 read_unlock(&tasklist_lock); 2536 } 2537 2538 /* superblock security operations */ 2539 2540 static int selinux_sb_alloc_security(struct super_block *sb) 2541 { 2542 struct superblock_security_struct *sbsec; 2543 2544 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 2545 if (!sbsec) 2546 return -ENOMEM; 2547 2548 mutex_init(&sbsec->lock); 2549 INIT_LIST_HEAD(&sbsec->isec_head); 2550 spin_lock_init(&sbsec->isec_lock); 2551 sbsec->sb = sb; 2552 sbsec->sid = SECINITSID_UNLABELED; 2553 sbsec->def_sid = SECINITSID_FILE; 2554 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2555 sb->s_security = sbsec; 2556 2557 return 0; 2558 } 2559 2560 static void selinux_sb_free_security(struct super_block *sb) 2561 { 2562 superblock_free_security(sb); 2563 } 2564 2565 static inline int opt_len(const char *s) 2566 { 2567 bool open_quote = false; 2568 int len; 2569 char c; 2570 2571 for (len = 0; (c = s[len]) != '\0'; len++) { 2572 if (c == '"') 2573 open_quote = !open_quote; 2574 if (c == ',' && !open_quote) 2575 break; 2576 } 2577 return len; 2578 } 2579 2580 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2581 { 2582 char *from = options; 2583 char *to = options; 2584 bool first = true; 2585 int rc; 2586 2587 while (1) { 2588 int len = opt_len(from); 2589 int token; 2590 char *arg = NULL; 2591 2592 token = match_opt_prefix(from, len, &arg); 2593 2594 if (token != Opt_error) { 2595 char *p, *q; 2596 2597 /* strip quotes */ 2598 if (arg) { 2599 for (p = q = arg; p < from + len; p++) { 2600 char c = *p; 2601 if (c != '"') 2602 *q++ = c; 2603 } 2604 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2605 if (!arg) { 2606 rc = -ENOMEM; 2607 goto free_opt; 2608 } 2609 } 2610 rc = selinux_add_opt(token, arg, mnt_opts); 2611 if (unlikely(rc)) { 2612 kfree(arg); 2613 goto free_opt; 2614 } 2615 } else { 2616 if (!first) { // copy with preceding comma 2617 from--; 2618 len++; 2619 } 2620 if (to != from) 2621 memmove(to, from, len); 2622 to += len; 2623 first = false; 2624 } 2625 if (!from[len]) 2626 break; 2627 from += len + 1; 2628 } 2629 *to = '\0'; 2630 return 0; 2631 2632 free_opt: 2633 if (*mnt_opts) { 2634 selinux_free_mnt_opts(*mnt_opts); 2635 *mnt_opts = NULL; 2636 } 2637 return rc; 2638 } 2639 2640 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2641 { 2642 struct selinux_mnt_opts *opts = mnt_opts; 2643 struct superblock_security_struct *sbsec = sb->s_security; 2644 u32 sid; 2645 int rc; 2646 2647 if (!(sbsec->flags & SE_SBINITIALIZED)) 2648 return 0; 2649 2650 if (!opts) 2651 return 0; 2652 2653 if (opts->fscontext) { 2654 rc = parse_sid(sb, opts->fscontext, &sid); 2655 if (rc) 2656 return rc; 2657 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2658 goto out_bad_option; 2659 } 2660 if (opts->context) { 2661 rc = parse_sid(sb, opts->context, &sid); 2662 if (rc) 2663 return rc; 2664 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2665 goto out_bad_option; 2666 } 2667 if (opts->rootcontext) { 2668 struct inode_security_struct *root_isec; 2669 root_isec = backing_inode_security(sb->s_root); 2670 rc = parse_sid(sb, opts->rootcontext, &sid); 2671 if (rc) 2672 return rc; 2673 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2674 goto out_bad_option; 2675 } 2676 if (opts->defcontext) { 2677 rc = parse_sid(sb, opts->defcontext, &sid); 2678 if (rc) 2679 return rc; 2680 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2681 goto out_bad_option; 2682 } 2683 return 0; 2684 2685 out_bad_option: 2686 pr_warn("SELinux: unable to change security options " 2687 "during remount (dev %s, type=%s)\n", sb->s_id, 2688 sb->s_type->name); 2689 return -EINVAL; 2690 } 2691 2692 static int selinux_sb_kern_mount(struct super_block *sb) 2693 { 2694 const struct cred *cred = current_cred(); 2695 struct common_audit_data ad; 2696 2697 ad.type = LSM_AUDIT_DATA_DENTRY; 2698 ad.u.dentry = sb->s_root; 2699 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2700 } 2701 2702 static int selinux_sb_statfs(struct dentry *dentry) 2703 { 2704 const struct cred *cred = current_cred(); 2705 struct common_audit_data ad; 2706 2707 ad.type = LSM_AUDIT_DATA_DENTRY; 2708 ad.u.dentry = dentry->d_sb->s_root; 2709 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2710 } 2711 2712 static int selinux_mount(const char *dev_name, 2713 const struct path *path, 2714 const char *type, 2715 unsigned long flags, 2716 void *data) 2717 { 2718 const struct cred *cred = current_cred(); 2719 2720 if (flags & MS_REMOUNT) 2721 return superblock_has_perm(cred, path->dentry->d_sb, 2722 FILESYSTEM__REMOUNT, NULL); 2723 else 2724 return path_has_perm(cred, path, FILE__MOUNTON); 2725 } 2726 2727 static int selinux_umount(struct vfsmount *mnt, int flags) 2728 { 2729 const struct cred *cred = current_cred(); 2730 2731 return superblock_has_perm(cred, mnt->mnt_sb, 2732 FILESYSTEM__UNMOUNT, NULL); 2733 } 2734 2735 static int selinux_fs_context_dup(struct fs_context *fc, 2736 struct fs_context *src_fc) 2737 { 2738 const struct selinux_mnt_opts *src = src_fc->security; 2739 struct selinux_mnt_opts *opts; 2740 2741 if (!src) 2742 return 0; 2743 2744 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 2745 if (!fc->security) 2746 return -ENOMEM; 2747 2748 opts = fc->security; 2749 2750 if (src->fscontext) { 2751 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); 2752 if (!opts->fscontext) 2753 return -ENOMEM; 2754 } 2755 if (src->context) { 2756 opts->context = kstrdup(src->context, GFP_KERNEL); 2757 if (!opts->context) 2758 return -ENOMEM; 2759 } 2760 if (src->rootcontext) { 2761 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); 2762 if (!opts->rootcontext) 2763 return -ENOMEM; 2764 } 2765 if (src->defcontext) { 2766 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); 2767 if (!opts->defcontext) 2768 return -ENOMEM; 2769 } 2770 return 0; 2771 } 2772 2773 static const struct fs_parameter_spec selinux_param_specs[] = { 2774 fsparam_string(CONTEXT_STR, Opt_context), 2775 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2776 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2777 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2778 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2779 {} 2780 }; 2781 2782 static const struct fs_parameter_description selinux_fs_parameters = { 2783 .name = "SELinux", 2784 .specs = selinux_param_specs, 2785 }; 2786 2787 static int selinux_fs_context_parse_param(struct fs_context *fc, 2788 struct fs_parameter *param) 2789 { 2790 struct fs_parse_result result; 2791 int opt, rc; 2792 2793 opt = fs_parse(fc, &selinux_fs_parameters, param, &result); 2794 if (opt < 0) 2795 return opt; 2796 2797 rc = selinux_add_opt(opt, param->string, &fc->security); 2798 if (!rc) { 2799 param->string = NULL; 2800 rc = 1; 2801 } 2802 return rc; 2803 } 2804 2805 /* inode security operations */ 2806 2807 static int selinux_inode_alloc_security(struct inode *inode) 2808 { 2809 struct inode_security_struct *isec = selinux_inode(inode); 2810 u32 sid = current_sid(); 2811 2812 spin_lock_init(&isec->lock); 2813 INIT_LIST_HEAD(&isec->list); 2814 isec->inode = inode; 2815 isec->sid = SECINITSID_UNLABELED; 2816 isec->sclass = SECCLASS_FILE; 2817 isec->task_sid = sid; 2818 isec->initialized = LABEL_INVALID; 2819 2820 return 0; 2821 } 2822 2823 static void selinux_inode_free_security(struct inode *inode) 2824 { 2825 inode_free_security(inode); 2826 } 2827 2828 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2829 const struct qstr *name, void **ctx, 2830 u32 *ctxlen) 2831 { 2832 u32 newsid; 2833 int rc; 2834 2835 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2836 d_inode(dentry->d_parent), name, 2837 inode_mode_to_security_class(mode), 2838 &newsid); 2839 if (rc) 2840 return rc; 2841 2842 return security_sid_to_context(&selinux_state, newsid, (char **)ctx, 2843 ctxlen); 2844 } 2845 2846 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2847 struct qstr *name, 2848 const struct cred *old, 2849 struct cred *new) 2850 { 2851 u32 newsid; 2852 int rc; 2853 struct task_security_struct *tsec; 2854 2855 rc = selinux_determine_inode_label(selinux_cred(old), 2856 d_inode(dentry->d_parent), name, 2857 inode_mode_to_security_class(mode), 2858 &newsid); 2859 if (rc) 2860 return rc; 2861 2862 tsec = selinux_cred(new); 2863 tsec->create_sid = newsid; 2864 return 0; 2865 } 2866 2867 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2868 const struct qstr *qstr, 2869 const char **name, 2870 void **value, size_t *len) 2871 { 2872 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2873 struct superblock_security_struct *sbsec; 2874 u32 newsid, clen; 2875 int rc; 2876 char *context; 2877 2878 sbsec = dir->i_sb->s_security; 2879 2880 newsid = tsec->create_sid; 2881 2882 rc = selinux_determine_inode_label(tsec, dir, qstr, 2883 inode_mode_to_security_class(inode->i_mode), 2884 &newsid); 2885 if (rc) 2886 return rc; 2887 2888 /* Possibly defer initialization to selinux_complete_init. */ 2889 if (sbsec->flags & SE_SBINITIALIZED) { 2890 struct inode_security_struct *isec = selinux_inode(inode); 2891 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2892 isec->sid = newsid; 2893 isec->initialized = LABEL_INITIALIZED; 2894 } 2895 2896 if (!selinux_initialized(&selinux_state) || 2897 !(sbsec->flags & SBLABEL_MNT)) 2898 return -EOPNOTSUPP; 2899 2900 if (name) 2901 *name = XATTR_SELINUX_SUFFIX; 2902 2903 if (value && len) { 2904 rc = security_sid_to_context_force(&selinux_state, newsid, 2905 &context, &clen); 2906 if (rc) 2907 return rc; 2908 *value = context; 2909 *len = clen; 2910 } 2911 2912 return 0; 2913 } 2914 2915 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 2916 { 2917 return may_create(dir, dentry, SECCLASS_FILE); 2918 } 2919 2920 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2921 { 2922 return may_link(dir, old_dentry, MAY_LINK); 2923 } 2924 2925 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2926 { 2927 return may_link(dir, dentry, MAY_UNLINK); 2928 } 2929 2930 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2931 { 2932 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2933 } 2934 2935 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 2936 { 2937 return may_create(dir, dentry, SECCLASS_DIR); 2938 } 2939 2940 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2941 { 2942 return may_link(dir, dentry, MAY_RMDIR); 2943 } 2944 2945 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 2946 { 2947 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2948 } 2949 2950 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2951 struct inode *new_inode, struct dentry *new_dentry) 2952 { 2953 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2954 } 2955 2956 static int selinux_inode_readlink(struct dentry *dentry) 2957 { 2958 const struct cred *cred = current_cred(); 2959 2960 return dentry_has_perm(cred, dentry, FILE__READ); 2961 } 2962 2963 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 2964 bool rcu) 2965 { 2966 const struct cred *cred = current_cred(); 2967 struct common_audit_data ad; 2968 struct inode_security_struct *isec; 2969 u32 sid; 2970 2971 validate_creds(cred); 2972 2973 ad.type = LSM_AUDIT_DATA_DENTRY; 2974 ad.u.dentry = dentry; 2975 sid = cred_sid(cred); 2976 isec = inode_security_rcu(inode, rcu); 2977 if (IS_ERR(isec)) 2978 return PTR_ERR(isec); 2979 2980 return avc_has_perm_flags(&selinux_state, 2981 sid, isec->sid, isec->sclass, FILE__READ, &ad, 2982 rcu ? MAY_NOT_BLOCK : 0); 2983 } 2984 2985 static noinline int audit_inode_permission(struct inode *inode, 2986 u32 perms, u32 audited, u32 denied, 2987 int result) 2988 { 2989 struct common_audit_data ad; 2990 struct inode_security_struct *isec = selinux_inode(inode); 2991 int rc; 2992 2993 ad.type = LSM_AUDIT_DATA_INODE; 2994 ad.u.inode = inode; 2995 2996 rc = slow_avc_audit(&selinux_state, 2997 current_sid(), isec->sid, isec->sclass, perms, 2998 audited, denied, result, &ad); 2999 if (rc) 3000 return rc; 3001 return 0; 3002 } 3003 3004 static int selinux_inode_permission(struct inode *inode, int mask) 3005 { 3006 const struct cred *cred = current_cred(); 3007 u32 perms; 3008 bool from_access; 3009 bool no_block = mask & MAY_NOT_BLOCK; 3010 struct inode_security_struct *isec; 3011 u32 sid; 3012 struct av_decision avd; 3013 int rc, rc2; 3014 u32 audited, denied; 3015 3016 from_access = mask & MAY_ACCESS; 3017 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3018 3019 /* No permission to check. Existence test. */ 3020 if (!mask) 3021 return 0; 3022 3023 validate_creds(cred); 3024 3025 if (unlikely(IS_PRIVATE(inode))) 3026 return 0; 3027 3028 perms = file_mask_to_av(inode->i_mode, mask); 3029 3030 sid = cred_sid(cred); 3031 isec = inode_security_rcu(inode, no_block); 3032 if (IS_ERR(isec)) 3033 return PTR_ERR(isec); 3034 3035 rc = avc_has_perm_noaudit(&selinux_state, 3036 sid, isec->sid, isec->sclass, perms, 3037 no_block ? AVC_NONBLOCKING : 0, 3038 &avd); 3039 audited = avc_audit_required(perms, &avd, rc, 3040 from_access ? FILE__AUDIT_ACCESS : 0, 3041 &denied); 3042 if (likely(!audited)) 3043 return rc; 3044 3045 /* fall back to ref-walk if we have to generate audit */ 3046 if (no_block) 3047 return -ECHILD; 3048 3049 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3050 if (rc2) 3051 return rc2; 3052 return rc; 3053 } 3054 3055 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3056 { 3057 const struct cred *cred = current_cred(); 3058 struct inode *inode = d_backing_inode(dentry); 3059 unsigned int ia_valid = iattr->ia_valid; 3060 __u32 av = FILE__WRITE; 3061 3062 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3063 if (ia_valid & ATTR_FORCE) { 3064 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3065 ATTR_FORCE); 3066 if (!ia_valid) 3067 return 0; 3068 } 3069 3070 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3071 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3072 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3073 3074 if (selinux_policycap_openperm() && 3075 inode->i_sb->s_magic != SOCKFS_MAGIC && 3076 (ia_valid & ATTR_SIZE) && 3077 !(ia_valid & ATTR_FILE)) 3078 av |= FILE__OPEN; 3079 3080 return dentry_has_perm(cred, dentry, av); 3081 } 3082 3083 static int selinux_inode_getattr(const struct path *path) 3084 { 3085 return path_has_perm(current_cred(), path, FILE__GETATTR); 3086 } 3087 3088 static bool has_cap_mac_admin(bool audit) 3089 { 3090 const struct cred *cred = current_cred(); 3091 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3092 3093 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3094 return false; 3095 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3096 return false; 3097 return true; 3098 } 3099 3100 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 3101 const void *value, size_t size, int flags) 3102 { 3103 struct inode *inode = d_backing_inode(dentry); 3104 struct inode_security_struct *isec; 3105 struct superblock_security_struct *sbsec; 3106 struct common_audit_data ad; 3107 u32 newsid, sid = current_sid(); 3108 int rc = 0; 3109 3110 if (strcmp(name, XATTR_NAME_SELINUX)) { 3111 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3112 if (rc) 3113 return rc; 3114 3115 /* Not an attribute we recognize, so just check the 3116 ordinary setattr permission. */ 3117 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3118 } 3119 3120 if (!selinux_initialized(&selinux_state)) 3121 return (inode_owner_or_capable(inode) ? 0 : -EPERM); 3122 3123 sbsec = inode->i_sb->s_security; 3124 if (!(sbsec->flags & SBLABEL_MNT)) 3125 return -EOPNOTSUPP; 3126 3127 if (!inode_owner_or_capable(inode)) 3128 return -EPERM; 3129 3130 ad.type = LSM_AUDIT_DATA_DENTRY; 3131 ad.u.dentry = dentry; 3132 3133 isec = backing_inode_security(dentry); 3134 rc = avc_has_perm(&selinux_state, 3135 sid, isec->sid, isec->sclass, 3136 FILE__RELABELFROM, &ad); 3137 if (rc) 3138 return rc; 3139 3140 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3141 GFP_KERNEL); 3142 if (rc == -EINVAL) { 3143 if (!has_cap_mac_admin(true)) { 3144 struct audit_buffer *ab; 3145 size_t audit_size; 3146 3147 /* We strip a nul only if it is at the end, otherwise the 3148 * context contains a nul and we should audit that */ 3149 if (value) { 3150 const char *str = value; 3151 3152 if (str[size - 1] == '\0') 3153 audit_size = size - 1; 3154 else 3155 audit_size = size; 3156 } else { 3157 audit_size = 0; 3158 } 3159 ab = audit_log_start(audit_context(), 3160 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3161 audit_log_format(ab, "op=setxattr invalid_context="); 3162 audit_log_n_untrustedstring(ab, value, audit_size); 3163 audit_log_end(ab); 3164 3165 return rc; 3166 } 3167 rc = security_context_to_sid_force(&selinux_state, value, 3168 size, &newsid); 3169 } 3170 if (rc) 3171 return rc; 3172 3173 rc = avc_has_perm(&selinux_state, 3174 sid, newsid, isec->sclass, 3175 FILE__RELABELTO, &ad); 3176 if (rc) 3177 return rc; 3178 3179 rc = security_validate_transition(&selinux_state, isec->sid, newsid, 3180 sid, isec->sclass); 3181 if (rc) 3182 return rc; 3183 3184 return avc_has_perm(&selinux_state, 3185 newsid, 3186 sbsec->sid, 3187 SECCLASS_FILESYSTEM, 3188 FILESYSTEM__ASSOCIATE, 3189 &ad); 3190 } 3191 3192 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3193 const void *value, size_t size, 3194 int flags) 3195 { 3196 struct inode *inode = d_backing_inode(dentry); 3197 struct inode_security_struct *isec; 3198 u32 newsid; 3199 int rc; 3200 3201 if (strcmp(name, XATTR_NAME_SELINUX)) { 3202 /* Not an attribute we recognize, so nothing to do. */ 3203 return; 3204 } 3205 3206 if (!selinux_initialized(&selinux_state)) { 3207 /* If we haven't even been initialized, then we can't validate 3208 * against a policy, so leave the label as invalid. It may 3209 * resolve to a valid label on the next revalidation try if 3210 * we've since initialized. 3211 */ 3212 return; 3213 } 3214 3215 rc = security_context_to_sid_force(&selinux_state, value, size, 3216 &newsid); 3217 if (rc) { 3218 pr_err("SELinux: unable to map context to SID" 3219 "for (%s, %lu), rc=%d\n", 3220 inode->i_sb->s_id, inode->i_ino, -rc); 3221 return; 3222 } 3223 3224 isec = backing_inode_security(dentry); 3225 spin_lock(&isec->lock); 3226 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3227 isec->sid = newsid; 3228 isec->initialized = LABEL_INITIALIZED; 3229 spin_unlock(&isec->lock); 3230 3231 return; 3232 } 3233 3234 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3235 { 3236 const struct cred *cred = current_cred(); 3237 3238 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3239 } 3240 3241 static int selinux_inode_listxattr(struct dentry *dentry) 3242 { 3243 const struct cred *cred = current_cred(); 3244 3245 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3246 } 3247 3248 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 3249 { 3250 if (strcmp(name, XATTR_NAME_SELINUX)) { 3251 int rc = cap_inode_removexattr(dentry, name); 3252 if (rc) 3253 return rc; 3254 3255 /* Not an attribute we recognize, so just check the 3256 ordinary setattr permission. */ 3257 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3258 } 3259 3260 /* No one is allowed to remove a SELinux security label. 3261 You can change the label, but all data must be labeled. */ 3262 return -EACCES; 3263 } 3264 3265 static int selinux_path_notify(const struct path *path, u64 mask, 3266 unsigned int obj_type) 3267 { 3268 int ret; 3269 u32 perm; 3270 3271 struct common_audit_data ad; 3272 3273 ad.type = LSM_AUDIT_DATA_PATH; 3274 ad.u.path = *path; 3275 3276 /* 3277 * Set permission needed based on the type of mark being set. 3278 * Performs an additional check for sb watches. 3279 */ 3280 switch (obj_type) { 3281 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3282 perm = FILE__WATCH_MOUNT; 3283 break; 3284 case FSNOTIFY_OBJ_TYPE_SB: 3285 perm = FILE__WATCH_SB; 3286 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3287 FILESYSTEM__WATCH, &ad); 3288 if (ret) 3289 return ret; 3290 break; 3291 case FSNOTIFY_OBJ_TYPE_INODE: 3292 perm = FILE__WATCH; 3293 break; 3294 default: 3295 return -EINVAL; 3296 } 3297 3298 /* blocking watches require the file:watch_with_perm permission */ 3299 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3300 perm |= FILE__WATCH_WITH_PERM; 3301 3302 /* watches on read-like events need the file:watch_reads permission */ 3303 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3304 perm |= FILE__WATCH_READS; 3305 3306 return path_has_perm(current_cred(), path, perm); 3307 } 3308 3309 /* 3310 * Copy the inode security context value to the user. 3311 * 3312 * Permission check is handled by selinux_inode_getxattr hook. 3313 */ 3314 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) 3315 { 3316 u32 size; 3317 int error; 3318 char *context = NULL; 3319 struct inode_security_struct *isec; 3320 3321 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3322 return -EOPNOTSUPP; 3323 3324 /* 3325 * If the caller has CAP_MAC_ADMIN, then get the raw context 3326 * value even if it is not defined by current policy; otherwise, 3327 * use the in-core value under current policy. 3328 * Use the non-auditing forms of the permission checks since 3329 * getxattr may be called by unprivileged processes commonly 3330 * and lack of permission just means that we fall back to the 3331 * in-core context value, not a denial. 3332 */ 3333 isec = inode_security(inode); 3334 if (has_cap_mac_admin(false)) 3335 error = security_sid_to_context_force(&selinux_state, 3336 isec->sid, &context, 3337 &size); 3338 else 3339 error = security_sid_to_context(&selinux_state, isec->sid, 3340 &context, &size); 3341 if (error) 3342 return error; 3343 error = size; 3344 if (alloc) { 3345 *buffer = context; 3346 goto out_nofree; 3347 } 3348 kfree(context); 3349 out_nofree: 3350 return error; 3351 } 3352 3353 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3354 const void *value, size_t size, int flags) 3355 { 3356 struct inode_security_struct *isec = inode_security_novalidate(inode); 3357 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 3358 u32 newsid; 3359 int rc; 3360 3361 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3362 return -EOPNOTSUPP; 3363 3364 if (!(sbsec->flags & SBLABEL_MNT)) 3365 return -EOPNOTSUPP; 3366 3367 if (!value || !size) 3368 return -EACCES; 3369 3370 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3371 GFP_KERNEL); 3372 if (rc) 3373 return rc; 3374 3375 spin_lock(&isec->lock); 3376 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3377 isec->sid = newsid; 3378 isec->initialized = LABEL_INITIALIZED; 3379 spin_unlock(&isec->lock); 3380 return 0; 3381 } 3382 3383 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3384 { 3385 const int len = sizeof(XATTR_NAME_SELINUX); 3386 if (buffer && len <= buffer_size) 3387 memcpy(buffer, XATTR_NAME_SELINUX, len); 3388 return len; 3389 } 3390 3391 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3392 { 3393 struct inode_security_struct *isec = inode_security_novalidate(inode); 3394 *secid = isec->sid; 3395 } 3396 3397 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3398 { 3399 u32 sid; 3400 struct task_security_struct *tsec; 3401 struct cred *new_creds = *new; 3402 3403 if (new_creds == NULL) { 3404 new_creds = prepare_creds(); 3405 if (!new_creds) 3406 return -ENOMEM; 3407 } 3408 3409 tsec = selinux_cred(new_creds); 3410 /* Get label from overlay inode and set it in create_sid */ 3411 selinux_inode_getsecid(d_inode(src), &sid); 3412 tsec->create_sid = sid; 3413 *new = new_creds; 3414 return 0; 3415 } 3416 3417 static int selinux_inode_copy_up_xattr(const char *name) 3418 { 3419 /* The copy_up hook above sets the initial context on an inode, but we 3420 * don't then want to overwrite it by blindly copying all the lower 3421 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3422 */ 3423 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3424 return 1; /* Discard */ 3425 /* 3426 * Any other attribute apart from SELINUX is not claimed, supported 3427 * by selinux. 3428 */ 3429 return -EOPNOTSUPP; 3430 } 3431 3432 /* kernfs node operations */ 3433 3434 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3435 struct kernfs_node *kn) 3436 { 3437 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3438 u32 parent_sid, newsid, clen; 3439 int rc; 3440 char *context; 3441 3442 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3443 if (rc == -ENODATA) 3444 return 0; 3445 else if (rc < 0) 3446 return rc; 3447 3448 clen = (u32)rc; 3449 context = kmalloc(clen, GFP_KERNEL); 3450 if (!context) 3451 return -ENOMEM; 3452 3453 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3454 if (rc < 0) { 3455 kfree(context); 3456 return rc; 3457 } 3458 3459 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, 3460 GFP_KERNEL); 3461 kfree(context); 3462 if (rc) 3463 return rc; 3464 3465 if (tsec->create_sid) { 3466 newsid = tsec->create_sid; 3467 } else { 3468 u16 secclass = inode_mode_to_security_class(kn->mode); 3469 struct qstr q; 3470 3471 q.name = kn->name; 3472 q.hash_len = hashlen_string(kn_dir, kn->name); 3473 3474 rc = security_transition_sid(&selinux_state, tsec->sid, 3475 parent_sid, secclass, &q, 3476 &newsid); 3477 if (rc) 3478 return rc; 3479 } 3480 3481 rc = security_sid_to_context_force(&selinux_state, newsid, 3482 &context, &clen); 3483 if (rc) 3484 return rc; 3485 3486 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3487 XATTR_CREATE); 3488 kfree(context); 3489 return rc; 3490 } 3491 3492 3493 /* file security operations */ 3494 3495 static int selinux_revalidate_file_permission(struct file *file, int mask) 3496 { 3497 const struct cred *cred = current_cred(); 3498 struct inode *inode = file_inode(file); 3499 3500 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3501 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3502 mask |= MAY_APPEND; 3503 3504 return file_has_perm(cred, file, 3505 file_mask_to_av(inode->i_mode, mask)); 3506 } 3507 3508 static int selinux_file_permission(struct file *file, int mask) 3509 { 3510 struct inode *inode = file_inode(file); 3511 struct file_security_struct *fsec = selinux_file(file); 3512 struct inode_security_struct *isec; 3513 u32 sid = current_sid(); 3514 3515 if (!mask) 3516 /* No permission to check. Existence test. */ 3517 return 0; 3518 3519 isec = inode_security(inode); 3520 if (sid == fsec->sid && fsec->isid == isec->sid && 3521 fsec->pseqno == avc_policy_seqno(&selinux_state)) 3522 /* No change since file_open check. */ 3523 return 0; 3524 3525 return selinux_revalidate_file_permission(file, mask); 3526 } 3527 3528 static int selinux_file_alloc_security(struct file *file) 3529 { 3530 struct file_security_struct *fsec = selinux_file(file); 3531 u32 sid = current_sid(); 3532 3533 fsec->sid = sid; 3534 fsec->fown_sid = sid; 3535 3536 return 0; 3537 } 3538 3539 /* 3540 * Check whether a task has the ioctl permission and cmd 3541 * operation to an inode. 3542 */ 3543 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3544 u32 requested, u16 cmd) 3545 { 3546 struct common_audit_data ad; 3547 struct file_security_struct *fsec = selinux_file(file); 3548 struct inode *inode = file_inode(file); 3549 struct inode_security_struct *isec; 3550 struct lsm_ioctlop_audit ioctl; 3551 u32 ssid = cred_sid(cred); 3552 int rc; 3553 u8 driver = cmd >> 8; 3554 u8 xperm = cmd & 0xff; 3555 3556 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3557 ad.u.op = &ioctl; 3558 ad.u.op->cmd = cmd; 3559 ad.u.op->path = file->f_path; 3560 3561 if (ssid != fsec->sid) { 3562 rc = avc_has_perm(&selinux_state, 3563 ssid, fsec->sid, 3564 SECCLASS_FD, 3565 FD__USE, 3566 &ad); 3567 if (rc) 3568 goto out; 3569 } 3570 3571 if (unlikely(IS_PRIVATE(inode))) 3572 return 0; 3573 3574 isec = inode_security(inode); 3575 rc = avc_has_extended_perms(&selinux_state, 3576 ssid, isec->sid, isec->sclass, 3577 requested, driver, xperm, &ad); 3578 out: 3579 return rc; 3580 } 3581 3582 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3583 unsigned long arg) 3584 { 3585 const struct cred *cred = current_cred(); 3586 int error = 0; 3587 3588 switch (cmd) { 3589 case FIONREAD: 3590 /* fall through */ 3591 case FIBMAP: 3592 /* fall through */ 3593 case FIGETBSZ: 3594 /* fall through */ 3595 case FS_IOC_GETFLAGS: 3596 /* fall through */ 3597 case FS_IOC_GETVERSION: 3598 error = file_has_perm(cred, file, FILE__GETATTR); 3599 break; 3600 3601 case FS_IOC_SETFLAGS: 3602 /* fall through */ 3603 case FS_IOC_SETVERSION: 3604 error = file_has_perm(cred, file, FILE__SETATTR); 3605 break; 3606 3607 /* sys_ioctl() checks */ 3608 case FIONBIO: 3609 /* fall through */ 3610 case FIOASYNC: 3611 error = file_has_perm(cred, file, 0); 3612 break; 3613 3614 case KDSKBENT: 3615 case KDSKBSENT: 3616 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3617 CAP_OPT_NONE, true); 3618 break; 3619 3620 /* default case assumes that the command will go 3621 * to the file's ioctl() function. 3622 */ 3623 default: 3624 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3625 } 3626 return error; 3627 } 3628 3629 static int default_noexec __ro_after_init; 3630 3631 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3632 { 3633 const struct cred *cred = current_cred(); 3634 u32 sid = cred_sid(cred); 3635 int rc = 0; 3636 3637 if (default_noexec && 3638 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3639 (!shared && (prot & PROT_WRITE)))) { 3640 /* 3641 * We are making executable an anonymous mapping or a 3642 * private file mapping that will also be writable. 3643 * This has an additional check. 3644 */ 3645 rc = avc_has_perm(&selinux_state, 3646 sid, sid, SECCLASS_PROCESS, 3647 PROCESS__EXECMEM, NULL); 3648 if (rc) 3649 goto error; 3650 } 3651 3652 if (file) { 3653 /* read access is always possible with a mapping */ 3654 u32 av = FILE__READ; 3655 3656 /* write access only matters if the mapping is shared */ 3657 if (shared && (prot & PROT_WRITE)) 3658 av |= FILE__WRITE; 3659 3660 if (prot & PROT_EXEC) 3661 av |= FILE__EXECUTE; 3662 3663 return file_has_perm(cred, file, av); 3664 } 3665 3666 error: 3667 return rc; 3668 } 3669 3670 static int selinux_mmap_addr(unsigned long addr) 3671 { 3672 int rc = 0; 3673 3674 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3675 u32 sid = current_sid(); 3676 rc = avc_has_perm(&selinux_state, 3677 sid, sid, SECCLASS_MEMPROTECT, 3678 MEMPROTECT__MMAP_ZERO, NULL); 3679 } 3680 3681 return rc; 3682 } 3683 3684 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3685 unsigned long prot, unsigned long flags) 3686 { 3687 struct common_audit_data ad; 3688 int rc; 3689 3690 if (file) { 3691 ad.type = LSM_AUDIT_DATA_FILE; 3692 ad.u.file = file; 3693 rc = inode_has_perm(current_cred(), file_inode(file), 3694 FILE__MAP, &ad); 3695 if (rc) 3696 return rc; 3697 } 3698 3699 if (selinux_state.checkreqprot) 3700 prot = reqprot; 3701 3702 return file_map_prot_check(file, prot, 3703 (flags & MAP_TYPE) == MAP_SHARED); 3704 } 3705 3706 static int selinux_file_mprotect(struct vm_area_struct *vma, 3707 unsigned long reqprot, 3708 unsigned long prot) 3709 { 3710 const struct cred *cred = current_cred(); 3711 u32 sid = cred_sid(cred); 3712 3713 if (selinux_state.checkreqprot) 3714 prot = reqprot; 3715 3716 if (default_noexec && 3717 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3718 int rc = 0; 3719 if (vma->vm_start >= vma->vm_mm->start_brk && 3720 vma->vm_end <= vma->vm_mm->brk) { 3721 rc = avc_has_perm(&selinux_state, 3722 sid, sid, SECCLASS_PROCESS, 3723 PROCESS__EXECHEAP, NULL); 3724 } else if (!vma->vm_file && 3725 ((vma->vm_start <= vma->vm_mm->start_stack && 3726 vma->vm_end >= vma->vm_mm->start_stack) || 3727 vma_is_stack_for_current(vma))) { 3728 rc = avc_has_perm(&selinux_state, 3729 sid, sid, SECCLASS_PROCESS, 3730 PROCESS__EXECSTACK, NULL); 3731 } else if (vma->vm_file && vma->anon_vma) { 3732 /* 3733 * We are making executable a file mapping that has 3734 * had some COW done. Since pages might have been 3735 * written, check ability to execute the possibly 3736 * modified content. This typically should only 3737 * occur for text relocations. 3738 */ 3739 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3740 } 3741 if (rc) 3742 return rc; 3743 } 3744 3745 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3746 } 3747 3748 static int selinux_file_lock(struct file *file, unsigned int cmd) 3749 { 3750 const struct cred *cred = current_cred(); 3751 3752 return file_has_perm(cred, file, FILE__LOCK); 3753 } 3754 3755 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3756 unsigned long arg) 3757 { 3758 const struct cred *cred = current_cred(); 3759 int err = 0; 3760 3761 switch (cmd) { 3762 case F_SETFL: 3763 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3764 err = file_has_perm(cred, file, FILE__WRITE); 3765 break; 3766 } 3767 /* fall through */ 3768 case F_SETOWN: 3769 case F_SETSIG: 3770 case F_GETFL: 3771 case F_GETOWN: 3772 case F_GETSIG: 3773 case F_GETOWNER_UIDS: 3774 /* Just check FD__USE permission */ 3775 err = file_has_perm(cred, file, 0); 3776 break; 3777 case F_GETLK: 3778 case F_SETLK: 3779 case F_SETLKW: 3780 case F_OFD_GETLK: 3781 case F_OFD_SETLK: 3782 case F_OFD_SETLKW: 3783 #if BITS_PER_LONG == 32 3784 case F_GETLK64: 3785 case F_SETLK64: 3786 case F_SETLKW64: 3787 #endif 3788 err = file_has_perm(cred, file, FILE__LOCK); 3789 break; 3790 } 3791 3792 return err; 3793 } 3794 3795 static void selinux_file_set_fowner(struct file *file) 3796 { 3797 struct file_security_struct *fsec; 3798 3799 fsec = selinux_file(file); 3800 fsec->fown_sid = current_sid(); 3801 } 3802 3803 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3804 struct fown_struct *fown, int signum) 3805 { 3806 struct file *file; 3807 u32 sid = task_sid(tsk); 3808 u32 perm; 3809 struct file_security_struct *fsec; 3810 3811 /* struct fown_struct is never outside the context of a struct file */ 3812 file = container_of(fown, struct file, f_owner); 3813 3814 fsec = selinux_file(file); 3815 3816 if (!signum) 3817 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3818 else 3819 perm = signal_to_av(signum); 3820 3821 return avc_has_perm(&selinux_state, 3822 fsec->fown_sid, sid, 3823 SECCLASS_PROCESS, perm, NULL); 3824 } 3825 3826 static int selinux_file_receive(struct file *file) 3827 { 3828 const struct cred *cred = current_cred(); 3829 3830 return file_has_perm(cred, file, file_to_av(file)); 3831 } 3832 3833 static int selinux_file_open(struct file *file) 3834 { 3835 struct file_security_struct *fsec; 3836 struct inode_security_struct *isec; 3837 3838 fsec = selinux_file(file); 3839 isec = inode_security(file_inode(file)); 3840 /* 3841 * Save inode label and policy sequence number 3842 * at open-time so that selinux_file_permission 3843 * can determine whether revalidation is necessary. 3844 * Task label is already saved in the file security 3845 * struct as its SID. 3846 */ 3847 fsec->isid = isec->sid; 3848 fsec->pseqno = avc_policy_seqno(&selinux_state); 3849 /* 3850 * Since the inode label or policy seqno may have changed 3851 * between the selinux_inode_permission check and the saving 3852 * of state above, recheck that access is still permitted. 3853 * Otherwise, access might never be revalidated against the 3854 * new inode label or new policy. 3855 * This check is not redundant - do not remove. 3856 */ 3857 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3858 } 3859 3860 /* task security operations */ 3861 3862 static int selinux_task_alloc(struct task_struct *task, 3863 unsigned long clone_flags) 3864 { 3865 u32 sid = current_sid(); 3866 3867 return avc_has_perm(&selinux_state, 3868 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3869 } 3870 3871 /* 3872 * prepare a new set of credentials for modification 3873 */ 3874 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3875 gfp_t gfp) 3876 { 3877 const struct task_security_struct *old_tsec = selinux_cred(old); 3878 struct task_security_struct *tsec = selinux_cred(new); 3879 3880 *tsec = *old_tsec; 3881 return 0; 3882 } 3883 3884 /* 3885 * transfer the SELinux data to a blank set of creds 3886 */ 3887 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3888 { 3889 const struct task_security_struct *old_tsec = selinux_cred(old); 3890 struct task_security_struct *tsec = selinux_cred(new); 3891 3892 *tsec = *old_tsec; 3893 } 3894 3895 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 3896 { 3897 *secid = cred_sid(c); 3898 } 3899 3900 /* 3901 * set the security data for a kernel service 3902 * - all the creation contexts are set to unlabelled 3903 */ 3904 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3905 { 3906 struct task_security_struct *tsec = selinux_cred(new); 3907 u32 sid = current_sid(); 3908 int ret; 3909 3910 ret = avc_has_perm(&selinux_state, 3911 sid, secid, 3912 SECCLASS_KERNEL_SERVICE, 3913 KERNEL_SERVICE__USE_AS_OVERRIDE, 3914 NULL); 3915 if (ret == 0) { 3916 tsec->sid = secid; 3917 tsec->create_sid = 0; 3918 tsec->keycreate_sid = 0; 3919 tsec->sockcreate_sid = 0; 3920 } 3921 return ret; 3922 } 3923 3924 /* 3925 * set the file creation context in a security record to the same as the 3926 * objective context of the specified inode 3927 */ 3928 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3929 { 3930 struct inode_security_struct *isec = inode_security(inode); 3931 struct task_security_struct *tsec = selinux_cred(new); 3932 u32 sid = current_sid(); 3933 int ret; 3934 3935 ret = avc_has_perm(&selinux_state, 3936 sid, isec->sid, 3937 SECCLASS_KERNEL_SERVICE, 3938 KERNEL_SERVICE__CREATE_FILES_AS, 3939 NULL); 3940 3941 if (ret == 0) 3942 tsec->create_sid = isec->sid; 3943 return ret; 3944 } 3945 3946 static int selinux_kernel_module_request(char *kmod_name) 3947 { 3948 struct common_audit_data ad; 3949 3950 ad.type = LSM_AUDIT_DATA_KMOD; 3951 ad.u.kmod_name = kmod_name; 3952 3953 return avc_has_perm(&selinux_state, 3954 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 3955 SYSTEM__MODULE_REQUEST, &ad); 3956 } 3957 3958 static int selinux_kernel_module_from_file(struct file *file) 3959 { 3960 struct common_audit_data ad; 3961 struct inode_security_struct *isec; 3962 struct file_security_struct *fsec; 3963 u32 sid = current_sid(); 3964 int rc; 3965 3966 /* init_module */ 3967 if (file == NULL) 3968 return avc_has_perm(&selinux_state, 3969 sid, sid, SECCLASS_SYSTEM, 3970 SYSTEM__MODULE_LOAD, NULL); 3971 3972 /* finit_module */ 3973 3974 ad.type = LSM_AUDIT_DATA_FILE; 3975 ad.u.file = file; 3976 3977 fsec = selinux_file(file); 3978 if (sid != fsec->sid) { 3979 rc = avc_has_perm(&selinux_state, 3980 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 3981 if (rc) 3982 return rc; 3983 } 3984 3985 isec = inode_security(file_inode(file)); 3986 return avc_has_perm(&selinux_state, 3987 sid, isec->sid, SECCLASS_SYSTEM, 3988 SYSTEM__MODULE_LOAD, &ad); 3989 } 3990 3991 static int selinux_kernel_read_file(struct file *file, 3992 enum kernel_read_file_id id) 3993 { 3994 int rc = 0; 3995 3996 switch (id) { 3997 case READING_MODULE: 3998 rc = selinux_kernel_module_from_file(file); 3999 break; 4000 default: 4001 break; 4002 } 4003 4004 return rc; 4005 } 4006 4007 static int selinux_kernel_load_data(enum kernel_load_data_id id) 4008 { 4009 int rc = 0; 4010 4011 switch (id) { 4012 case LOADING_MODULE: 4013 rc = selinux_kernel_module_from_file(NULL); 4014 default: 4015 break; 4016 } 4017 4018 return rc; 4019 } 4020 4021 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4022 { 4023 return avc_has_perm(&selinux_state, 4024 current_sid(), task_sid(p), SECCLASS_PROCESS, 4025 PROCESS__SETPGID, NULL); 4026 } 4027 4028 static int selinux_task_getpgid(struct task_struct *p) 4029 { 4030 return avc_has_perm(&selinux_state, 4031 current_sid(), task_sid(p), SECCLASS_PROCESS, 4032 PROCESS__GETPGID, NULL); 4033 } 4034 4035 static int selinux_task_getsid(struct task_struct *p) 4036 { 4037 return avc_has_perm(&selinux_state, 4038 current_sid(), task_sid(p), SECCLASS_PROCESS, 4039 PROCESS__GETSESSION, NULL); 4040 } 4041 4042 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 4043 { 4044 *secid = task_sid(p); 4045 } 4046 4047 static int selinux_task_setnice(struct task_struct *p, int nice) 4048 { 4049 return avc_has_perm(&selinux_state, 4050 current_sid(), task_sid(p), SECCLASS_PROCESS, 4051 PROCESS__SETSCHED, NULL); 4052 } 4053 4054 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4055 { 4056 return avc_has_perm(&selinux_state, 4057 current_sid(), task_sid(p), SECCLASS_PROCESS, 4058 PROCESS__SETSCHED, NULL); 4059 } 4060 4061 static int selinux_task_getioprio(struct task_struct *p) 4062 { 4063 return avc_has_perm(&selinux_state, 4064 current_sid(), task_sid(p), SECCLASS_PROCESS, 4065 PROCESS__GETSCHED, NULL); 4066 } 4067 4068 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4069 unsigned int flags) 4070 { 4071 u32 av = 0; 4072 4073 if (!flags) 4074 return 0; 4075 if (flags & LSM_PRLIMIT_WRITE) 4076 av |= PROCESS__SETRLIMIT; 4077 if (flags & LSM_PRLIMIT_READ) 4078 av |= PROCESS__GETRLIMIT; 4079 return avc_has_perm(&selinux_state, 4080 cred_sid(cred), cred_sid(tcred), 4081 SECCLASS_PROCESS, av, NULL); 4082 } 4083 4084 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4085 struct rlimit *new_rlim) 4086 { 4087 struct rlimit *old_rlim = p->signal->rlim + resource; 4088 4089 /* Control the ability to change the hard limit (whether 4090 lowering or raising it), so that the hard limit can 4091 later be used as a safe reset point for the soft limit 4092 upon context transitions. See selinux_bprm_committing_creds. */ 4093 if (old_rlim->rlim_max != new_rlim->rlim_max) 4094 return avc_has_perm(&selinux_state, 4095 current_sid(), task_sid(p), 4096 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4097 4098 return 0; 4099 } 4100 4101 static int selinux_task_setscheduler(struct task_struct *p) 4102 { 4103 return avc_has_perm(&selinux_state, 4104 current_sid(), task_sid(p), SECCLASS_PROCESS, 4105 PROCESS__SETSCHED, NULL); 4106 } 4107 4108 static int selinux_task_getscheduler(struct task_struct *p) 4109 { 4110 return avc_has_perm(&selinux_state, 4111 current_sid(), task_sid(p), SECCLASS_PROCESS, 4112 PROCESS__GETSCHED, NULL); 4113 } 4114 4115 static int selinux_task_movememory(struct task_struct *p) 4116 { 4117 return avc_has_perm(&selinux_state, 4118 current_sid(), task_sid(p), SECCLASS_PROCESS, 4119 PROCESS__SETSCHED, NULL); 4120 } 4121 4122 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4123 int sig, const struct cred *cred) 4124 { 4125 u32 secid; 4126 u32 perm; 4127 4128 if (!sig) 4129 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4130 else 4131 perm = signal_to_av(sig); 4132 if (!cred) 4133 secid = current_sid(); 4134 else 4135 secid = cred_sid(cred); 4136 return avc_has_perm(&selinux_state, 4137 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL); 4138 } 4139 4140 static void selinux_task_to_inode(struct task_struct *p, 4141 struct inode *inode) 4142 { 4143 struct inode_security_struct *isec = selinux_inode(inode); 4144 u32 sid = task_sid(p); 4145 4146 spin_lock(&isec->lock); 4147 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4148 isec->sid = sid; 4149 isec->initialized = LABEL_INITIALIZED; 4150 spin_unlock(&isec->lock); 4151 } 4152 4153 /* Returns error only if unable to parse addresses */ 4154 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4155 struct common_audit_data *ad, u8 *proto) 4156 { 4157 int offset, ihlen, ret = -EINVAL; 4158 struct iphdr _iph, *ih; 4159 4160 offset = skb_network_offset(skb); 4161 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4162 if (ih == NULL) 4163 goto out; 4164 4165 ihlen = ih->ihl * 4; 4166 if (ihlen < sizeof(_iph)) 4167 goto out; 4168 4169 ad->u.net->v4info.saddr = ih->saddr; 4170 ad->u.net->v4info.daddr = ih->daddr; 4171 ret = 0; 4172 4173 if (proto) 4174 *proto = ih->protocol; 4175 4176 switch (ih->protocol) { 4177 case IPPROTO_TCP: { 4178 struct tcphdr _tcph, *th; 4179 4180 if (ntohs(ih->frag_off) & IP_OFFSET) 4181 break; 4182 4183 offset += ihlen; 4184 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4185 if (th == NULL) 4186 break; 4187 4188 ad->u.net->sport = th->source; 4189 ad->u.net->dport = th->dest; 4190 break; 4191 } 4192 4193 case IPPROTO_UDP: { 4194 struct udphdr _udph, *uh; 4195 4196 if (ntohs(ih->frag_off) & IP_OFFSET) 4197 break; 4198 4199 offset += ihlen; 4200 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4201 if (uh == NULL) 4202 break; 4203 4204 ad->u.net->sport = uh->source; 4205 ad->u.net->dport = uh->dest; 4206 break; 4207 } 4208 4209 case IPPROTO_DCCP: { 4210 struct dccp_hdr _dccph, *dh; 4211 4212 if (ntohs(ih->frag_off) & IP_OFFSET) 4213 break; 4214 4215 offset += ihlen; 4216 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4217 if (dh == NULL) 4218 break; 4219 4220 ad->u.net->sport = dh->dccph_sport; 4221 ad->u.net->dport = dh->dccph_dport; 4222 break; 4223 } 4224 4225 #if IS_ENABLED(CONFIG_IP_SCTP) 4226 case IPPROTO_SCTP: { 4227 struct sctphdr _sctph, *sh; 4228 4229 if (ntohs(ih->frag_off) & IP_OFFSET) 4230 break; 4231 4232 offset += ihlen; 4233 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4234 if (sh == NULL) 4235 break; 4236 4237 ad->u.net->sport = sh->source; 4238 ad->u.net->dport = sh->dest; 4239 break; 4240 } 4241 #endif 4242 default: 4243 break; 4244 } 4245 out: 4246 return ret; 4247 } 4248 4249 #if IS_ENABLED(CONFIG_IPV6) 4250 4251 /* Returns error only if unable to parse addresses */ 4252 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4253 struct common_audit_data *ad, u8 *proto) 4254 { 4255 u8 nexthdr; 4256 int ret = -EINVAL, offset; 4257 struct ipv6hdr _ipv6h, *ip6; 4258 __be16 frag_off; 4259 4260 offset = skb_network_offset(skb); 4261 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4262 if (ip6 == NULL) 4263 goto out; 4264 4265 ad->u.net->v6info.saddr = ip6->saddr; 4266 ad->u.net->v6info.daddr = ip6->daddr; 4267 ret = 0; 4268 4269 nexthdr = ip6->nexthdr; 4270 offset += sizeof(_ipv6h); 4271 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4272 if (offset < 0) 4273 goto out; 4274 4275 if (proto) 4276 *proto = nexthdr; 4277 4278 switch (nexthdr) { 4279 case IPPROTO_TCP: { 4280 struct tcphdr _tcph, *th; 4281 4282 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4283 if (th == NULL) 4284 break; 4285 4286 ad->u.net->sport = th->source; 4287 ad->u.net->dport = th->dest; 4288 break; 4289 } 4290 4291 case IPPROTO_UDP: { 4292 struct udphdr _udph, *uh; 4293 4294 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4295 if (uh == NULL) 4296 break; 4297 4298 ad->u.net->sport = uh->source; 4299 ad->u.net->dport = uh->dest; 4300 break; 4301 } 4302 4303 case IPPROTO_DCCP: { 4304 struct dccp_hdr _dccph, *dh; 4305 4306 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4307 if (dh == NULL) 4308 break; 4309 4310 ad->u.net->sport = dh->dccph_sport; 4311 ad->u.net->dport = dh->dccph_dport; 4312 break; 4313 } 4314 4315 #if IS_ENABLED(CONFIG_IP_SCTP) 4316 case IPPROTO_SCTP: { 4317 struct sctphdr _sctph, *sh; 4318 4319 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4320 if (sh == NULL) 4321 break; 4322 4323 ad->u.net->sport = sh->source; 4324 ad->u.net->dport = sh->dest; 4325 break; 4326 } 4327 #endif 4328 /* includes fragments */ 4329 default: 4330 break; 4331 } 4332 out: 4333 return ret; 4334 } 4335 4336 #endif /* IPV6 */ 4337 4338 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4339 char **_addrp, int src, u8 *proto) 4340 { 4341 char *addrp; 4342 int ret; 4343 4344 switch (ad->u.net->family) { 4345 case PF_INET: 4346 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4347 if (ret) 4348 goto parse_error; 4349 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4350 &ad->u.net->v4info.daddr); 4351 goto okay; 4352 4353 #if IS_ENABLED(CONFIG_IPV6) 4354 case PF_INET6: 4355 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4356 if (ret) 4357 goto parse_error; 4358 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4359 &ad->u.net->v6info.daddr); 4360 goto okay; 4361 #endif /* IPV6 */ 4362 default: 4363 addrp = NULL; 4364 goto okay; 4365 } 4366 4367 parse_error: 4368 pr_warn( 4369 "SELinux: failure in selinux_parse_skb()," 4370 " unable to parse packet\n"); 4371 return ret; 4372 4373 okay: 4374 if (_addrp) 4375 *_addrp = addrp; 4376 return 0; 4377 } 4378 4379 /** 4380 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4381 * @skb: the packet 4382 * @family: protocol family 4383 * @sid: the packet's peer label SID 4384 * 4385 * Description: 4386 * Check the various different forms of network peer labeling and determine 4387 * the peer label/SID for the packet; most of the magic actually occurs in 4388 * the security server function security_net_peersid_cmp(). The function 4389 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4390 * or -EACCES if @sid is invalid due to inconsistencies with the different 4391 * peer labels. 4392 * 4393 */ 4394 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4395 { 4396 int err; 4397 u32 xfrm_sid; 4398 u32 nlbl_sid; 4399 u32 nlbl_type; 4400 4401 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4402 if (unlikely(err)) 4403 return -EACCES; 4404 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4405 if (unlikely(err)) 4406 return -EACCES; 4407 4408 err = security_net_peersid_resolve(&selinux_state, nlbl_sid, 4409 nlbl_type, xfrm_sid, sid); 4410 if (unlikely(err)) { 4411 pr_warn( 4412 "SELinux: failure in selinux_skb_peerlbl_sid()," 4413 " unable to determine packet's peer label\n"); 4414 return -EACCES; 4415 } 4416 4417 return 0; 4418 } 4419 4420 /** 4421 * selinux_conn_sid - Determine the child socket label for a connection 4422 * @sk_sid: the parent socket's SID 4423 * @skb_sid: the packet's SID 4424 * @conn_sid: the resulting connection SID 4425 * 4426 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4427 * combined with the MLS information from @skb_sid in order to create 4428 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy 4429 * of @sk_sid. Returns zero on success, negative values on failure. 4430 * 4431 */ 4432 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4433 { 4434 int err = 0; 4435 4436 if (skb_sid != SECSID_NULL) 4437 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid, 4438 conn_sid); 4439 else 4440 *conn_sid = sk_sid; 4441 4442 return err; 4443 } 4444 4445 /* socket security operations */ 4446 4447 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4448 u16 secclass, u32 *socksid) 4449 { 4450 if (tsec->sockcreate_sid > SECSID_NULL) { 4451 *socksid = tsec->sockcreate_sid; 4452 return 0; 4453 } 4454 4455 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid, 4456 secclass, NULL, socksid); 4457 } 4458 4459 static int sock_has_perm(struct sock *sk, u32 perms) 4460 { 4461 struct sk_security_struct *sksec = sk->sk_security; 4462 struct common_audit_data ad; 4463 struct lsm_network_audit net = {0,}; 4464 4465 if (sksec->sid == SECINITSID_KERNEL) 4466 return 0; 4467 4468 ad.type = LSM_AUDIT_DATA_NET; 4469 ad.u.net = &net; 4470 ad.u.net->sk = sk; 4471 4472 return avc_has_perm(&selinux_state, 4473 current_sid(), sksec->sid, sksec->sclass, perms, 4474 &ad); 4475 } 4476 4477 static int selinux_socket_create(int family, int type, 4478 int protocol, int kern) 4479 { 4480 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4481 u32 newsid; 4482 u16 secclass; 4483 int rc; 4484 4485 if (kern) 4486 return 0; 4487 4488 secclass = socket_type_to_security_class(family, type, protocol); 4489 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4490 if (rc) 4491 return rc; 4492 4493 return avc_has_perm(&selinux_state, 4494 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4495 } 4496 4497 static int selinux_socket_post_create(struct socket *sock, int family, 4498 int type, int protocol, int kern) 4499 { 4500 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4501 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4502 struct sk_security_struct *sksec; 4503 u16 sclass = socket_type_to_security_class(family, type, protocol); 4504 u32 sid = SECINITSID_KERNEL; 4505 int err = 0; 4506 4507 if (!kern) { 4508 err = socket_sockcreate_sid(tsec, sclass, &sid); 4509 if (err) 4510 return err; 4511 } 4512 4513 isec->sclass = sclass; 4514 isec->sid = sid; 4515 isec->initialized = LABEL_INITIALIZED; 4516 4517 if (sock->sk) { 4518 sksec = sock->sk->sk_security; 4519 sksec->sclass = sclass; 4520 sksec->sid = sid; 4521 /* Allows detection of the first association on this socket */ 4522 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4523 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4524 4525 err = selinux_netlbl_socket_post_create(sock->sk, family); 4526 } 4527 4528 return err; 4529 } 4530 4531 static int selinux_socket_socketpair(struct socket *socka, 4532 struct socket *sockb) 4533 { 4534 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4535 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4536 4537 sksec_a->peer_sid = sksec_b->sid; 4538 sksec_b->peer_sid = sksec_a->sid; 4539 4540 return 0; 4541 } 4542 4543 /* Range of port numbers used to automatically bind. 4544 Need to determine whether we should perform a name_bind 4545 permission check between the socket and the port number. */ 4546 4547 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4548 { 4549 struct sock *sk = sock->sk; 4550 struct sk_security_struct *sksec = sk->sk_security; 4551 u16 family; 4552 int err; 4553 4554 err = sock_has_perm(sk, SOCKET__BIND); 4555 if (err) 4556 goto out; 4557 4558 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4559 family = sk->sk_family; 4560 if (family == PF_INET || family == PF_INET6) { 4561 char *addrp; 4562 struct common_audit_data ad; 4563 struct lsm_network_audit net = {0,}; 4564 struct sockaddr_in *addr4 = NULL; 4565 struct sockaddr_in6 *addr6 = NULL; 4566 u16 family_sa; 4567 unsigned short snum; 4568 u32 sid, node_perm; 4569 4570 /* 4571 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4572 * that validates multiple binding addresses. Because of this 4573 * need to check address->sa_family as it is possible to have 4574 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4575 */ 4576 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4577 return -EINVAL; 4578 family_sa = address->sa_family; 4579 switch (family_sa) { 4580 case AF_UNSPEC: 4581 case AF_INET: 4582 if (addrlen < sizeof(struct sockaddr_in)) 4583 return -EINVAL; 4584 addr4 = (struct sockaddr_in *)address; 4585 if (family_sa == AF_UNSPEC) { 4586 /* see __inet_bind(), we only want to allow 4587 * AF_UNSPEC if the address is INADDR_ANY 4588 */ 4589 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4590 goto err_af; 4591 family_sa = AF_INET; 4592 } 4593 snum = ntohs(addr4->sin_port); 4594 addrp = (char *)&addr4->sin_addr.s_addr; 4595 break; 4596 case AF_INET6: 4597 if (addrlen < SIN6_LEN_RFC2133) 4598 return -EINVAL; 4599 addr6 = (struct sockaddr_in6 *)address; 4600 snum = ntohs(addr6->sin6_port); 4601 addrp = (char *)&addr6->sin6_addr.s6_addr; 4602 break; 4603 default: 4604 goto err_af; 4605 } 4606 4607 ad.type = LSM_AUDIT_DATA_NET; 4608 ad.u.net = &net; 4609 ad.u.net->sport = htons(snum); 4610 ad.u.net->family = family_sa; 4611 4612 if (snum) { 4613 int low, high; 4614 4615 inet_get_local_port_range(sock_net(sk), &low, &high); 4616 4617 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4618 snum < low || snum > high) { 4619 err = sel_netport_sid(sk->sk_protocol, 4620 snum, &sid); 4621 if (err) 4622 goto out; 4623 err = avc_has_perm(&selinux_state, 4624 sksec->sid, sid, 4625 sksec->sclass, 4626 SOCKET__NAME_BIND, &ad); 4627 if (err) 4628 goto out; 4629 } 4630 } 4631 4632 switch (sksec->sclass) { 4633 case SECCLASS_TCP_SOCKET: 4634 node_perm = TCP_SOCKET__NODE_BIND; 4635 break; 4636 4637 case SECCLASS_UDP_SOCKET: 4638 node_perm = UDP_SOCKET__NODE_BIND; 4639 break; 4640 4641 case SECCLASS_DCCP_SOCKET: 4642 node_perm = DCCP_SOCKET__NODE_BIND; 4643 break; 4644 4645 case SECCLASS_SCTP_SOCKET: 4646 node_perm = SCTP_SOCKET__NODE_BIND; 4647 break; 4648 4649 default: 4650 node_perm = RAWIP_SOCKET__NODE_BIND; 4651 break; 4652 } 4653 4654 err = sel_netnode_sid(addrp, family_sa, &sid); 4655 if (err) 4656 goto out; 4657 4658 if (family_sa == AF_INET) 4659 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4660 else 4661 ad.u.net->v6info.saddr = addr6->sin6_addr; 4662 4663 err = avc_has_perm(&selinux_state, 4664 sksec->sid, sid, 4665 sksec->sclass, node_perm, &ad); 4666 if (err) 4667 goto out; 4668 } 4669 out: 4670 return err; 4671 err_af: 4672 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4673 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4674 return -EINVAL; 4675 return -EAFNOSUPPORT; 4676 } 4677 4678 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4679 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4680 */ 4681 static int selinux_socket_connect_helper(struct socket *sock, 4682 struct sockaddr *address, int addrlen) 4683 { 4684 struct sock *sk = sock->sk; 4685 struct sk_security_struct *sksec = sk->sk_security; 4686 int err; 4687 4688 err = sock_has_perm(sk, SOCKET__CONNECT); 4689 if (err) 4690 return err; 4691 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4692 return -EINVAL; 4693 4694 /* connect(AF_UNSPEC) has special handling, as it is a documented 4695 * way to disconnect the socket 4696 */ 4697 if (address->sa_family == AF_UNSPEC) 4698 return 0; 4699 4700 /* 4701 * If a TCP, DCCP or SCTP socket, check name_connect permission 4702 * for the port. 4703 */ 4704 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4705 sksec->sclass == SECCLASS_DCCP_SOCKET || 4706 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4707 struct common_audit_data ad; 4708 struct lsm_network_audit net = {0,}; 4709 struct sockaddr_in *addr4 = NULL; 4710 struct sockaddr_in6 *addr6 = NULL; 4711 unsigned short snum; 4712 u32 sid, perm; 4713 4714 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4715 * that validates multiple connect addresses. Because of this 4716 * need to check address->sa_family as it is possible to have 4717 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4718 */ 4719 switch (address->sa_family) { 4720 case AF_INET: 4721 addr4 = (struct sockaddr_in *)address; 4722 if (addrlen < sizeof(struct sockaddr_in)) 4723 return -EINVAL; 4724 snum = ntohs(addr4->sin_port); 4725 break; 4726 case AF_INET6: 4727 addr6 = (struct sockaddr_in6 *)address; 4728 if (addrlen < SIN6_LEN_RFC2133) 4729 return -EINVAL; 4730 snum = ntohs(addr6->sin6_port); 4731 break; 4732 default: 4733 /* Note that SCTP services expect -EINVAL, whereas 4734 * others expect -EAFNOSUPPORT. 4735 */ 4736 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4737 return -EINVAL; 4738 else 4739 return -EAFNOSUPPORT; 4740 } 4741 4742 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4743 if (err) 4744 return err; 4745 4746 switch (sksec->sclass) { 4747 case SECCLASS_TCP_SOCKET: 4748 perm = TCP_SOCKET__NAME_CONNECT; 4749 break; 4750 case SECCLASS_DCCP_SOCKET: 4751 perm = DCCP_SOCKET__NAME_CONNECT; 4752 break; 4753 case SECCLASS_SCTP_SOCKET: 4754 perm = SCTP_SOCKET__NAME_CONNECT; 4755 break; 4756 } 4757 4758 ad.type = LSM_AUDIT_DATA_NET; 4759 ad.u.net = &net; 4760 ad.u.net->dport = htons(snum); 4761 ad.u.net->family = address->sa_family; 4762 err = avc_has_perm(&selinux_state, 4763 sksec->sid, sid, sksec->sclass, perm, &ad); 4764 if (err) 4765 return err; 4766 } 4767 4768 return 0; 4769 } 4770 4771 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4772 static int selinux_socket_connect(struct socket *sock, 4773 struct sockaddr *address, int addrlen) 4774 { 4775 int err; 4776 struct sock *sk = sock->sk; 4777 4778 err = selinux_socket_connect_helper(sock, address, addrlen); 4779 if (err) 4780 return err; 4781 4782 return selinux_netlbl_socket_connect(sk, address); 4783 } 4784 4785 static int selinux_socket_listen(struct socket *sock, int backlog) 4786 { 4787 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4788 } 4789 4790 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4791 { 4792 int err; 4793 struct inode_security_struct *isec; 4794 struct inode_security_struct *newisec; 4795 u16 sclass; 4796 u32 sid; 4797 4798 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4799 if (err) 4800 return err; 4801 4802 isec = inode_security_novalidate(SOCK_INODE(sock)); 4803 spin_lock(&isec->lock); 4804 sclass = isec->sclass; 4805 sid = isec->sid; 4806 spin_unlock(&isec->lock); 4807 4808 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4809 newisec->sclass = sclass; 4810 newisec->sid = sid; 4811 newisec->initialized = LABEL_INITIALIZED; 4812 4813 return 0; 4814 } 4815 4816 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4817 int size) 4818 { 4819 return sock_has_perm(sock->sk, SOCKET__WRITE); 4820 } 4821 4822 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4823 int size, int flags) 4824 { 4825 return sock_has_perm(sock->sk, SOCKET__READ); 4826 } 4827 4828 static int selinux_socket_getsockname(struct socket *sock) 4829 { 4830 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4831 } 4832 4833 static int selinux_socket_getpeername(struct socket *sock) 4834 { 4835 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4836 } 4837 4838 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4839 { 4840 int err; 4841 4842 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4843 if (err) 4844 return err; 4845 4846 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4847 } 4848 4849 static int selinux_socket_getsockopt(struct socket *sock, int level, 4850 int optname) 4851 { 4852 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4853 } 4854 4855 static int selinux_socket_shutdown(struct socket *sock, int how) 4856 { 4857 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4858 } 4859 4860 static int selinux_socket_unix_stream_connect(struct sock *sock, 4861 struct sock *other, 4862 struct sock *newsk) 4863 { 4864 struct sk_security_struct *sksec_sock = sock->sk_security; 4865 struct sk_security_struct *sksec_other = other->sk_security; 4866 struct sk_security_struct *sksec_new = newsk->sk_security; 4867 struct common_audit_data ad; 4868 struct lsm_network_audit net = {0,}; 4869 int err; 4870 4871 ad.type = LSM_AUDIT_DATA_NET; 4872 ad.u.net = &net; 4873 ad.u.net->sk = other; 4874 4875 err = avc_has_perm(&selinux_state, 4876 sksec_sock->sid, sksec_other->sid, 4877 sksec_other->sclass, 4878 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4879 if (err) 4880 return err; 4881 4882 /* server child socket */ 4883 sksec_new->peer_sid = sksec_sock->sid; 4884 err = security_sid_mls_copy(&selinux_state, sksec_other->sid, 4885 sksec_sock->sid, &sksec_new->sid); 4886 if (err) 4887 return err; 4888 4889 /* connecting socket */ 4890 sksec_sock->peer_sid = sksec_new->sid; 4891 4892 return 0; 4893 } 4894 4895 static int selinux_socket_unix_may_send(struct socket *sock, 4896 struct socket *other) 4897 { 4898 struct sk_security_struct *ssec = sock->sk->sk_security; 4899 struct sk_security_struct *osec = other->sk->sk_security; 4900 struct common_audit_data ad; 4901 struct lsm_network_audit net = {0,}; 4902 4903 ad.type = LSM_AUDIT_DATA_NET; 4904 ad.u.net = &net; 4905 ad.u.net->sk = other->sk; 4906 4907 return avc_has_perm(&selinux_state, 4908 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4909 &ad); 4910 } 4911 4912 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4913 char *addrp, u16 family, u32 peer_sid, 4914 struct common_audit_data *ad) 4915 { 4916 int err; 4917 u32 if_sid; 4918 u32 node_sid; 4919 4920 err = sel_netif_sid(ns, ifindex, &if_sid); 4921 if (err) 4922 return err; 4923 err = avc_has_perm(&selinux_state, 4924 peer_sid, if_sid, 4925 SECCLASS_NETIF, NETIF__INGRESS, ad); 4926 if (err) 4927 return err; 4928 4929 err = sel_netnode_sid(addrp, family, &node_sid); 4930 if (err) 4931 return err; 4932 return avc_has_perm(&selinux_state, 4933 peer_sid, node_sid, 4934 SECCLASS_NODE, NODE__RECVFROM, ad); 4935 } 4936 4937 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4938 u16 family) 4939 { 4940 int err = 0; 4941 struct sk_security_struct *sksec = sk->sk_security; 4942 u32 sk_sid = sksec->sid; 4943 struct common_audit_data ad; 4944 struct lsm_network_audit net = {0,}; 4945 char *addrp; 4946 4947 ad.type = LSM_AUDIT_DATA_NET; 4948 ad.u.net = &net; 4949 ad.u.net->netif = skb->skb_iif; 4950 ad.u.net->family = family; 4951 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4952 if (err) 4953 return err; 4954 4955 if (selinux_secmark_enabled()) { 4956 err = avc_has_perm(&selinux_state, 4957 sk_sid, skb->secmark, SECCLASS_PACKET, 4958 PACKET__RECV, &ad); 4959 if (err) 4960 return err; 4961 } 4962 4963 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4964 if (err) 4965 return err; 4966 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4967 4968 return err; 4969 } 4970 4971 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4972 { 4973 int err; 4974 struct sk_security_struct *sksec = sk->sk_security; 4975 u16 family = sk->sk_family; 4976 u32 sk_sid = sksec->sid; 4977 struct common_audit_data ad; 4978 struct lsm_network_audit net = {0,}; 4979 char *addrp; 4980 u8 secmark_active; 4981 u8 peerlbl_active; 4982 4983 if (family != PF_INET && family != PF_INET6) 4984 return 0; 4985 4986 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4987 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4988 family = PF_INET; 4989 4990 /* If any sort of compatibility mode is enabled then handoff processing 4991 * to the selinux_sock_rcv_skb_compat() function to deal with the 4992 * special handling. We do this in an attempt to keep this function 4993 * as fast and as clean as possible. */ 4994 if (!selinux_policycap_netpeer()) 4995 return selinux_sock_rcv_skb_compat(sk, skb, family); 4996 4997 secmark_active = selinux_secmark_enabled(); 4998 peerlbl_active = selinux_peerlbl_enabled(); 4999 if (!secmark_active && !peerlbl_active) 5000 return 0; 5001 5002 ad.type = LSM_AUDIT_DATA_NET; 5003 ad.u.net = &net; 5004 ad.u.net->netif = skb->skb_iif; 5005 ad.u.net->family = family; 5006 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5007 if (err) 5008 return err; 5009 5010 if (peerlbl_active) { 5011 u32 peer_sid; 5012 5013 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5014 if (err) 5015 return err; 5016 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5017 addrp, family, peer_sid, &ad); 5018 if (err) { 5019 selinux_netlbl_err(skb, family, err, 0); 5020 return err; 5021 } 5022 err = avc_has_perm(&selinux_state, 5023 sk_sid, peer_sid, SECCLASS_PEER, 5024 PEER__RECV, &ad); 5025 if (err) { 5026 selinux_netlbl_err(skb, family, err, 0); 5027 return err; 5028 } 5029 } 5030 5031 if (secmark_active) { 5032 err = avc_has_perm(&selinux_state, 5033 sk_sid, skb->secmark, SECCLASS_PACKET, 5034 PACKET__RECV, &ad); 5035 if (err) 5036 return err; 5037 } 5038 5039 return err; 5040 } 5041 5042 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 5043 int __user *optlen, unsigned len) 5044 { 5045 int err = 0; 5046 char *scontext; 5047 u32 scontext_len; 5048 struct sk_security_struct *sksec = sock->sk->sk_security; 5049 u32 peer_sid = SECSID_NULL; 5050 5051 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5052 sksec->sclass == SECCLASS_TCP_SOCKET || 5053 sksec->sclass == SECCLASS_SCTP_SOCKET) 5054 peer_sid = sksec->peer_sid; 5055 if (peer_sid == SECSID_NULL) 5056 return -ENOPROTOOPT; 5057 5058 err = security_sid_to_context(&selinux_state, peer_sid, &scontext, 5059 &scontext_len); 5060 if (err) 5061 return err; 5062 5063 if (scontext_len > len) { 5064 err = -ERANGE; 5065 goto out_len; 5066 } 5067 5068 if (copy_to_user(optval, scontext, scontext_len)) 5069 err = -EFAULT; 5070 5071 out_len: 5072 if (put_user(scontext_len, optlen)) 5073 err = -EFAULT; 5074 kfree(scontext); 5075 return err; 5076 } 5077 5078 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5079 { 5080 u32 peer_secid = SECSID_NULL; 5081 u16 family; 5082 struct inode_security_struct *isec; 5083 5084 if (skb && skb->protocol == htons(ETH_P_IP)) 5085 family = PF_INET; 5086 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5087 family = PF_INET6; 5088 else if (sock) 5089 family = sock->sk->sk_family; 5090 else 5091 goto out; 5092 5093 if (sock && family == PF_UNIX) { 5094 isec = inode_security_novalidate(SOCK_INODE(sock)); 5095 peer_secid = isec->sid; 5096 } else if (skb) 5097 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5098 5099 out: 5100 *secid = peer_secid; 5101 if (peer_secid == SECSID_NULL) 5102 return -EINVAL; 5103 return 0; 5104 } 5105 5106 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5107 { 5108 struct sk_security_struct *sksec; 5109 5110 sksec = kzalloc(sizeof(*sksec), priority); 5111 if (!sksec) 5112 return -ENOMEM; 5113 5114 sksec->peer_sid = SECINITSID_UNLABELED; 5115 sksec->sid = SECINITSID_UNLABELED; 5116 sksec->sclass = SECCLASS_SOCKET; 5117 selinux_netlbl_sk_security_reset(sksec); 5118 sk->sk_security = sksec; 5119 5120 return 0; 5121 } 5122 5123 static void selinux_sk_free_security(struct sock *sk) 5124 { 5125 struct sk_security_struct *sksec = sk->sk_security; 5126 5127 sk->sk_security = NULL; 5128 selinux_netlbl_sk_security_free(sksec); 5129 kfree(sksec); 5130 } 5131 5132 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5133 { 5134 struct sk_security_struct *sksec = sk->sk_security; 5135 struct sk_security_struct *newsksec = newsk->sk_security; 5136 5137 newsksec->sid = sksec->sid; 5138 newsksec->peer_sid = sksec->peer_sid; 5139 newsksec->sclass = sksec->sclass; 5140 5141 selinux_netlbl_sk_security_reset(newsksec); 5142 } 5143 5144 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 5145 { 5146 if (!sk) 5147 *secid = SECINITSID_ANY_SOCKET; 5148 else { 5149 struct sk_security_struct *sksec = sk->sk_security; 5150 5151 *secid = sksec->sid; 5152 } 5153 } 5154 5155 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5156 { 5157 struct inode_security_struct *isec = 5158 inode_security_novalidate(SOCK_INODE(parent)); 5159 struct sk_security_struct *sksec = sk->sk_security; 5160 5161 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5162 sk->sk_family == PF_UNIX) 5163 isec->sid = sksec->sid; 5164 sksec->sclass = isec->sclass; 5165 } 5166 5167 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming 5168 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association 5169 * already present). 5170 */ 5171 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep, 5172 struct sk_buff *skb) 5173 { 5174 struct sk_security_struct *sksec = ep->base.sk->sk_security; 5175 struct common_audit_data ad; 5176 struct lsm_network_audit net = {0,}; 5177 u8 peerlbl_active; 5178 u32 peer_sid = SECINITSID_UNLABELED; 5179 u32 conn_sid; 5180 int err = 0; 5181 5182 if (!selinux_policycap_extsockclass()) 5183 return 0; 5184 5185 peerlbl_active = selinux_peerlbl_enabled(); 5186 5187 if (peerlbl_active) { 5188 /* This will return peer_sid = SECSID_NULL if there are 5189 * no peer labels, see security_net_peersid_resolve(). 5190 */ 5191 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family, 5192 &peer_sid); 5193 if (err) 5194 return err; 5195 5196 if (peer_sid == SECSID_NULL) 5197 peer_sid = SECINITSID_UNLABELED; 5198 } 5199 5200 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5201 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5202 5203 /* Here as first association on socket. As the peer SID 5204 * was allowed by peer recv (and the netif/node checks), 5205 * then it is approved by policy and used as the primary 5206 * peer SID for getpeercon(3). 5207 */ 5208 sksec->peer_sid = peer_sid; 5209 } else if (sksec->peer_sid != peer_sid) { 5210 /* Other association peer SIDs are checked to enforce 5211 * consistency among the peer SIDs. 5212 */ 5213 ad.type = LSM_AUDIT_DATA_NET; 5214 ad.u.net = &net; 5215 ad.u.net->sk = ep->base.sk; 5216 err = avc_has_perm(&selinux_state, 5217 sksec->peer_sid, peer_sid, sksec->sclass, 5218 SCTP_SOCKET__ASSOCIATION, &ad); 5219 if (err) 5220 return err; 5221 } 5222 5223 /* Compute the MLS component for the connection and store 5224 * the information in ep. This will be used by SCTP TCP type 5225 * sockets and peeled off connections as they cause a new 5226 * socket to be generated. selinux_sctp_sk_clone() will then 5227 * plug this into the new socket. 5228 */ 5229 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid); 5230 if (err) 5231 return err; 5232 5233 ep->secid = conn_sid; 5234 ep->peer_secid = peer_sid; 5235 5236 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5237 return selinux_netlbl_sctp_assoc_request(ep, skb); 5238 } 5239 5240 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5241 * based on their @optname. 5242 */ 5243 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5244 struct sockaddr *address, 5245 int addrlen) 5246 { 5247 int len, err = 0, walk_size = 0; 5248 void *addr_buf; 5249 struct sockaddr *addr; 5250 struct socket *sock; 5251 5252 if (!selinux_policycap_extsockclass()) 5253 return 0; 5254 5255 /* Process one or more addresses that may be IPv4 or IPv6 */ 5256 sock = sk->sk_socket; 5257 addr_buf = address; 5258 5259 while (walk_size < addrlen) { 5260 if (walk_size + sizeof(sa_family_t) > addrlen) 5261 return -EINVAL; 5262 5263 addr = addr_buf; 5264 switch (addr->sa_family) { 5265 case AF_UNSPEC: 5266 case AF_INET: 5267 len = sizeof(struct sockaddr_in); 5268 break; 5269 case AF_INET6: 5270 len = sizeof(struct sockaddr_in6); 5271 break; 5272 default: 5273 return -EINVAL; 5274 } 5275 5276 if (walk_size + len > addrlen) 5277 return -EINVAL; 5278 5279 err = -EINVAL; 5280 switch (optname) { 5281 /* Bind checks */ 5282 case SCTP_PRIMARY_ADDR: 5283 case SCTP_SET_PEER_PRIMARY_ADDR: 5284 case SCTP_SOCKOPT_BINDX_ADD: 5285 err = selinux_socket_bind(sock, addr, len); 5286 break; 5287 /* Connect checks */ 5288 case SCTP_SOCKOPT_CONNECTX: 5289 case SCTP_PARAM_SET_PRIMARY: 5290 case SCTP_PARAM_ADD_IP: 5291 case SCTP_SENDMSG_CONNECT: 5292 err = selinux_socket_connect_helper(sock, addr, len); 5293 if (err) 5294 return err; 5295 5296 /* As selinux_sctp_bind_connect() is called by the 5297 * SCTP protocol layer, the socket is already locked, 5298 * therefore selinux_netlbl_socket_connect_locked() is 5299 * is called here. The situations handled are: 5300 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5301 * whenever a new IP address is added or when a new 5302 * primary address is selected. 5303 * Note that an SCTP connect(2) call happens before 5304 * the SCTP protocol layer and is handled via 5305 * selinux_socket_connect(). 5306 */ 5307 err = selinux_netlbl_socket_connect_locked(sk, addr); 5308 break; 5309 } 5310 5311 if (err) 5312 return err; 5313 5314 addr_buf += len; 5315 walk_size += len; 5316 } 5317 5318 return 0; 5319 } 5320 5321 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5322 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk, 5323 struct sock *newsk) 5324 { 5325 struct sk_security_struct *sksec = sk->sk_security; 5326 struct sk_security_struct *newsksec = newsk->sk_security; 5327 5328 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5329 * the non-sctp clone version. 5330 */ 5331 if (!selinux_policycap_extsockclass()) 5332 return selinux_sk_clone_security(sk, newsk); 5333 5334 newsksec->sid = ep->secid; 5335 newsksec->peer_sid = ep->peer_secid; 5336 newsksec->sclass = sksec->sclass; 5337 selinux_netlbl_sctp_sk_clone(sk, newsk); 5338 } 5339 5340 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 5341 struct request_sock *req) 5342 { 5343 struct sk_security_struct *sksec = sk->sk_security; 5344 int err; 5345 u16 family = req->rsk_ops->family; 5346 u32 connsid; 5347 u32 peersid; 5348 5349 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5350 if (err) 5351 return err; 5352 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5353 if (err) 5354 return err; 5355 req->secid = connsid; 5356 req->peer_secid = peersid; 5357 5358 return selinux_netlbl_inet_conn_request(req, family); 5359 } 5360 5361 static void selinux_inet_csk_clone(struct sock *newsk, 5362 const struct request_sock *req) 5363 { 5364 struct sk_security_struct *newsksec = newsk->sk_security; 5365 5366 newsksec->sid = req->secid; 5367 newsksec->peer_sid = req->peer_secid; 5368 /* NOTE: Ideally, we should also get the isec->sid for the 5369 new socket in sync, but we don't have the isec available yet. 5370 So we will wait until sock_graft to do it, by which 5371 time it will have been created and available. */ 5372 5373 /* We don't need to take any sort of lock here as we are the only 5374 * thread with access to newsksec */ 5375 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5376 } 5377 5378 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5379 { 5380 u16 family = sk->sk_family; 5381 struct sk_security_struct *sksec = sk->sk_security; 5382 5383 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5384 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5385 family = PF_INET; 5386 5387 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5388 } 5389 5390 static int selinux_secmark_relabel_packet(u32 sid) 5391 { 5392 const struct task_security_struct *__tsec; 5393 u32 tsid; 5394 5395 __tsec = selinux_cred(current_cred()); 5396 tsid = __tsec->sid; 5397 5398 return avc_has_perm(&selinux_state, 5399 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5400 NULL); 5401 } 5402 5403 static void selinux_secmark_refcount_inc(void) 5404 { 5405 atomic_inc(&selinux_secmark_refcount); 5406 } 5407 5408 static void selinux_secmark_refcount_dec(void) 5409 { 5410 atomic_dec(&selinux_secmark_refcount); 5411 } 5412 5413 static void selinux_req_classify_flow(const struct request_sock *req, 5414 struct flowi *fl) 5415 { 5416 fl->flowi_secid = req->secid; 5417 } 5418 5419 static int selinux_tun_dev_alloc_security(void **security) 5420 { 5421 struct tun_security_struct *tunsec; 5422 5423 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5424 if (!tunsec) 5425 return -ENOMEM; 5426 tunsec->sid = current_sid(); 5427 5428 *security = tunsec; 5429 return 0; 5430 } 5431 5432 static void selinux_tun_dev_free_security(void *security) 5433 { 5434 kfree(security); 5435 } 5436 5437 static int selinux_tun_dev_create(void) 5438 { 5439 u32 sid = current_sid(); 5440 5441 /* we aren't taking into account the "sockcreate" SID since the socket 5442 * that is being created here is not a socket in the traditional sense, 5443 * instead it is a private sock, accessible only to the kernel, and 5444 * representing a wide range of network traffic spanning multiple 5445 * connections unlike traditional sockets - check the TUN driver to 5446 * get a better understanding of why this socket is special */ 5447 5448 return avc_has_perm(&selinux_state, 5449 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5450 NULL); 5451 } 5452 5453 static int selinux_tun_dev_attach_queue(void *security) 5454 { 5455 struct tun_security_struct *tunsec = security; 5456 5457 return avc_has_perm(&selinux_state, 5458 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5459 TUN_SOCKET__ATTACH_QUEUE, NULL); 5460 } 5461 5462 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5463 { 5464 struct tun_security_struct *tunsec = security; 5465 struct sk_security_struct *sksec = sk->sk_security; 5466 5467 /* we don't currently perform any NetLabel based labeling here and it 5468 * isn't clear that we would want to do so anyway; while we could apply 5469 * labeling without the support of the TUN user the resulting labeled 5470 * traffic from the other end of the connection would almost certainly 5471 * cause confusion to the TUN user that had no idea network labeling 5472 * protocols were being used */ 5473 5474 sksec->sid = tunsec->sid; 5475 sksec->sclass = SECCLASS_TUN_SOCKET; 5476 5477 return 0; 5478 } 5479 5480 static int selinux_tun_dev_open(void *security) 5481 { 5482 struct tun_security_struct *tunsec = security; 5483 u32 sid = current_sid(); 5484 int err; 5485 5486 err = avc_has_perm(&selinux_state, 5487 sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5488 TUN_SOCKET__RELABELFROM, NULL); 5489 if (err) 5490 return err; 5491 err = avc_has_perm(&selinux_state, 5492 sid, sid, SECCLASS_TUN_SOCKET, 5493 TUN_SOCKET__RELABELTO, NULL); 5494 if (err) 5495 return err; 5496 tunsec->sid = sid; 5497 5498 return 0; 5499 } 5500 5501 #ifdef CONFIG_NETFILTER 5502 5503 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5504 const struct net_device *indev, 5505 u16 family) 5506 { 5507 int err; 5508 char *addrp; 5509 u32 peer_sid; 5510 struct common_audit_data ad; 5511 struct lsm_network_audit net = {0,}; 5512 u8 secmark_active; 5513 u8 netlbl_active; 5514 u8 peerlbl_active; 5515 5516 if (!selinux_policycap_netpeer()) 5517 return NF_ACCEPT; 5518 5519 secmark_active = selinux_secmark_enabled(); 5520 netlbl_active = netlbl_enabled(); 5521 peerlbl_active = selinux_peerlbl_enabled(); 5522 if (!secmark_active && !peerlbl_active) 5523 return NF_ACCEPT; 5524 5525 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5526 return NF_DROP; 5527 5528 ad.type = LSM_AUDIT_DATA_NET; 5529 ad.u.net = &net; 5530 ad.u.net->netif = indev->ifindex; 5531 ad.u.net->family = family; 5532 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5533 return NF_DROP; 5534 5535 if (peerlbl_active) { 5536 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5537 addrp, family, peer_sid, &ad); 5538 if (err) { 5539 selinux_netlbl_err(skb, family, err, 1); 5540 return NF_DROP; 5541 } 5542 } 5543 5544 if (secmark_active) 5545 if (avc_has_perm(&selinux_state, 5546 peer_sid, skb->secmark, 5547 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5548 return NF_DROP; 5549 5550 if (netlbl_active) 5551 /* we do this in the FORWARD path and not the POST_ROUTING 5552 * path because we want to make sure we apply the necessary 5553 * labeling before IPsec is applied so we can leverage AH 5554 * protection */ 5555 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5556 return NF_DROP; 5557 5558 return NF_ACCEPT; 5559 } 5560 5561 static unsigned int selinux_ipv4_forward(void *priv, 5562 struct sk_buff *skb, 5563 const struct nf_hook_state *state) 5564 { 5565 return selinux_ip_forward(skb, state->in, PF_INET); 5566 } 5567 5568 #if IS_ENABLED(CONFIG_IPV6) 5569 static unsigned int selinux_ipv6_forward(void *priv, 5570 struct sk_buff *skb, 5571 const struct nf_hook_state *state) 5572 { 5573 return selinux_ip_forward(skb, state->in, PF_INET6); 5574 } 5575 #endif /* IPV6 */ 5576 5577 static unsigned int selinux_ip_output(struct sk_buff *skb, 5578 u16 family) 5579 { 5580 struct sock *sk; 5581 u32 sid; 5582 5583 if (!netlbl_enabled()) 5584 return NF_ACCEPT; 5585 5586 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5587 * because we want to make sure we apply the necessary labeling 5588 * before IPsec is applied so we can leverage AH protection */ 5589 sk = skb->sk; 5590 if (sk) { 5591 struct sk_security_struct *sksec; 5592 5593 if (sk_listener(sk)) 5594 /* if the socket is the listening state then this 5595 * packet is a SYN-ACK packet which means it needs to 5596 * be labeled based on the connection/request_sock and 5597 * not the parent socket. unfortunately, we can't 5598 * lookup the request_sock yet as it isn't queued on 5599 * the parent socket until after the SYN-ACK is sent. 5600 * the "solution" is to simply pass the packet as-is 5601 * as any IP option based labeling should be copied 5602 * from the initial connection request (in the IP 5603 * layer). it is far from ideal, but until we get a 5604 * security label in the packet itself this is the 5605 * best we can do. */ 5606 return NF_ACCEPT; 5607 5608 /* standard practice, label using the parent socket */ 5609 sksec = sk->sk_security; 5610 sid = sksec->sid; 5611 } else 5612 sid = SECINITSID_KERNEL; 5613 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5614 return NF_DROP; 5615 5616 return NF_ACCEPT; 5617 } 5618 5619 static unsigned int selinux_ipv4_output(void *priv, 5620 struct sk_buff *skb, 5621 const struct nf_hook_state *state) 5622 { 5623 return selinux_ip_output(skb, PF_INET); 5624 } 5625 5626 #if IS_ENABLED(CONFIG_IPV6) 5627 static unsigned int selinux_ipv6_output(void *priv, 5628 struct sk_buff *skb, 5629 const struct nf_hook_state *state) 5630 { 5631 return selinux_ip_output(skb, PF_INET6); 5632 } 5633 #endif /* IPV6 */ 5634 5635 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5636 int ifindex, 5637 u16 family) 5638 { 5639 struct sock *sk = skb_to_full_sk(skb); 5640 struct sk_security_struct *sksec; 5641 struct common_audit_data ad; 5642 struct lsm_network_audit net = {0,}; 5643 char *addrp; 5644 u8 proto; 5645 5646 if (sk == NULL) 5647 return NF_ACCEPT; 5648 sksec = sk->sk_security; 5649 5650 ad.type = LSM_AUDIT_DATA_NET; 5651 ad.u.net = &net; 5652 ad.u.net->netif = ifindex; 5653 ad.u.net->family = family; 5654 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5655 return NF_DROP; 5656 5657 if (selinux_secmark_enabled()) 5658 if (avc_has_perm(&selinux_state, 5659 sksec->sid, skb->secmark, 5660 SECCLASS_PACKET, PACKET__SEND, &ad)) 5661 return NF_DROP_ERR(-ECONNREFUSED); 5662 5663 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5664 return NF_DROP_ERR(-ECONNREFUSED); 5665 5666 return NF_ACCEPT; 5667 } 5668 5669 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5670 const struct net_device *outdev, 5671 u16 family) 5672 { 5673 u32 secmark_perm; 5674 u32 peer_sid; 5675 int ifindex = outdev->ifindex; 5676 struct sock *sk; 5677 struct common_audit_data ad; 5678 struct lsm_network_audit net = {0,}; 5679 char *addrp; 5680 u8 secmark_active; 5681 u8 peerlbl_active; 5682 5683 /* If any sort of compatibility mode is enabled then handoff processing 5684 * to the selinux_ip_postroute_compat() function to deal with the 5685 * special handling. We do this in an attempt to keep this function 5686 * as fast and as clean as possible. */ 5687 if (!selinux_policycap_netpeer()) 5688 return selinux_ip_postroute_compat(skb, ifindex, family); 5689 5690 secmark_active = selinux_secmark_enabled(); 5691 peerlbl_active = selinux_peerlbl_enabled(); 5692 if (!secmark_active && !peerlbl_active) 5693 return NF_ACCEPT; 5694 5695 sk = skb_to_full_sk(skb); 5696 5697 #ifdef CONFIG_XFRM 5698 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5699 * packet transformation so allow the packet to pass without any checks 5700 * since we'll have another chance to perform access control checks 5701 * when the packet is on it's final way out. 5702 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5703 * is NULL, in this case go ahead and apply access control. 5704 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5705 * TCP listening state we cannot wait until the XFRM processing 5706 * is done as we will miss out on the SA label if we do; 5707 * unfortunately, this means more work, but it is only once per 5708 * connection. */ 5709 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5710 !(sk && sk_listener(sk))) 5711 return NF_ACCEPT; 5712 #endif 5713 5714 if (sk == NULL) { 5715 /* Without an associated socket the packet is either coming 5716 * from the kernel or it is being forwarded; check the packet 5717 * to determine which and if the packet is being forwarded 5718 * query the packet directly to determine the security label. */ 5719 if (skb->skb_iif) { 5720 secmark_perm = PACKET__FORWARD_OUT; 5721 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5722 return NF_DROP; 5723 } else { 5724 secmark_perm = PACKET__SEND; 5725 peer_sid = SECINITSID_KERNEL; 5726 } 5727 } else if (sk_listener(sk)) { 5728 /* Locally generated packet but the associated socket is in the 5729 * listening state which means this is a SYN-ACK packet. In 5730 * this particular case the correct security label is assigned 5731 * to the connection/request_sock but unfortunately we can't 5732 * query the request_sock as it isn't queued on the parent 5733 * socket until after the SYN-ACK packet is sent; the only 5734 * viable choice is to regenerate the label like we do in 5735 * selinux_inet_conn_request(). See also selinux_ip_output() 5736 * for similar problems. */ 5737 u32 skb_sid; 5738 struct sk_security_struct *sksec; 5739 5740 sksec = sk->sk_security; 5741 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5742 return NF_DROP; 5743 /* At this point, if the returned skb peerlbl is SECSID_NULL 5744 * and the packet has been through at least one XFRM 5745 * transformation then we must be dealing with the "final" 5746 * form of labeled IPsec packet; since we've already applied 5747 * all of our access controls on this packet we can safely 5748 * pass the packet. */ 5749 if (skb_sid == SECSID_NULL) { 5750 switch (family) { 5751 case PF_INET: 5752 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5753 return NF_ACCEPT; 5754 break; 5755 case PF_INET6: 5756 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5757 return NF_ACCEPT; 5758 break; 5759 default: 5760 return NF_DROP_ERR(-ECONNREFUSED); 5761 } 5762 } 5763 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5764 return NF_DROP; 5765 secmark_perm = PACKET__SEND; 5766 } else { 5767 /* Locally generated packet, fetch the security label from the 5768 * associated socket. */ 5769 struct sk_security_struct *sksec = sk->sk_security; 5770 peer_sid = sksec->sid; 5771 secmark_perm = PACKET__SEND; 5772 } 5773 5774 ad.type = LSM_AUDIT_DATA_NET; 5775 ad.u.net = &net; 5776 ad.u.net->netif = ifindex; 5777 ad.u.net->family = family; 5778 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5779 return NF_DROP; 5780 5781 if (secmark_active) 5782 if (avc_has_perm(&selinux_state, 5783 peer_sid, skb->secmark, 5784 SECCLASS_PACKET, secmark_perm, &ad)) 5785 return NF_DROP_ERR(-ECONNREFUSED); 5786 5787 if (peerlbl_active) { 5788 u32 if_sid; 5789 u32 node_sid; 5790 5791 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5792 return NF_DROP; 5793 if (avc_has_perm(&selinux_state, 5794 peer_sid, if_sid, 5795 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5796 return NF_DROP_ERR(-ECONNREFUSED); 5797 5798 if (sel_netnode_sid(addrp, family, &node_sid)) 5799 return NF_DROP; 5800 if (avc_has_perm(&selinux_state, 5801 peer_sid, node_sid, 5802 SECCLASS_NODE, NODE__SENDTO, &ad)) 5803 return NF_DROP_ERR(-ECONNREFUSED); 5804 } 5805 5806 return NF_ACCEPT; 5807 } 5808 5809 static unsigned int selinux_ipv4_postroute(void *priv, 5810 struct sk_buff *skb, 5811 const struct nf_hook_state *state) 5812 { 5813 return selinux_ip_postroute(skb, state->out, PF_INET); 5814 } 5815 5816 #if IS_ENABLED(CONFIG_IPV6) 5817 static unsigned int selinux_ipv6_postroute(void *priv, 5818 struct sk_buff *skb, 5819 const struct nf_hook_state *state) 5820 { 5821 return selinux_ip_postroute(skb, state->out, PF_INET6); 5822 } 5823 #endif /* IPV6 */ 5824 5825 #endif /* CONFIG_NETFILTER */ 5826 5827 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5828 { 5829 int err = 0; 5830 u32 perm; 5831 struct nlmsghdr *nlh; 5832 struct sk_security_struct *sksec = sk->sk_security; 5833 5834 if (skb->len < NLMSG_HDRLEN) { 5835 err = -EINVAL; 5836 goto out; 5837 } 5838 nlh = nlmsg_hdr(skb); 5839 5840 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); 5841 if (err) { 5842 if (err == -EINVAL) { 5843 pr_warn_ratelimited("SELinux: unrecognized netlink" 5844 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5845 " pid=%d comm=%s\n", 5846 sk->sk_protocol, nlh->nlmsg_type, 5847 secclass_map[sksec->sclass - 1].name, 5848 task_pid_nr(current), current->comm); 5849 if (!enforcing_enabled(&selinux_state) || 5850 security_get_allow_unknown(&selinux_state)) 5851 err = 0; 5852 } 5853 5854 /* Ignore */ 5855 if (err == -ENOENT) 5856 err = 0; 5857 goto out; 5858 } 5859 5860 err = sock_has_perm(sk, perm); 5861 out: 5862 return err; 5863 } 5864 5865 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5866 { 5867 isec->sclass = sclass; 5868 isec->sid = current_sid(); 5869 } 5870 5871 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5872 u32 perms) 5873 { 5874 struct ipc_security_struct *isec; 5875 struct common_audit_data ad; 5876 u32 sid = current_sid(); 5877 5878 isec = selinux_ipc(ipc_perms); 5879 5880 ad.type = LSM_AUDIT_DATA_IPC; 5881 ad.u.ipc_id = ipc_perms->key; 5882 5883 return avc_has_perm(&selinux_state, 5884 sid, isec->sid, isec->sclass, perms, &ad); 5885 } 5886 5887 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5888 { 5889 struct msg_security_struct *msec; 5890 5891 msec = selinux_msg_msg(msg); 5892 msec->sid = SECINITSID_UNLABELED; 5893 5894 return 0; 5895 } 5896 5897 /* message queue security operations */ 5898 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5899 { 5900 struct ipc_security_struct *isec; 5901 struct common_audit_data ad; 5902 u32 sid = current_sid(); 5903 int rc; 5904 5905 isec = selinux_ipc(msq); 5906 ipc_init_security(isec, SECCLASS_MSGQ); 5907 5908 ad.type = LSM_AUDIT_DATA_IPC; 5909 ad.u.ipc_id = msq->key; 5910 5911 rc = avc_has_perm(&selinux_state, 5912 sid, isec->sid, SECCLASS_MSGQ, 5913 MSGQ__CREATE, &ad); 5914 return rc; 5915 } 5916 5917 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 5918 { 5919 struct ipc_security_struct *isec; 5920 struct common_audit_data ad; 5921 u32 sid = current_sid(); 5922 5923 isec = selinux_ipc(msq); 5924 5925 ad.type = LSM_AUDIT_DATA_IPC; 5926 ad.u.ipc_id = msq->key; 5927 5928 return avc_has_perm(&selinux_state, 5929 sid, isec->sid, SECCLASS_MSGQ, 5930 MSGQ__ASSOCIATE, &ad); 5931 } 5932 5933 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 5934 { 5935 int err; 5936 int perms; 5937 5938 switch (cmd) { 5939 case IPC_INFO: 5940 case MSG_INFO: 5941 /* No specific object, just general system-wide information. */ 5942 return avc_has_perm(&selinux_state, 5943 current_sid(), SECINITSID_KERNEL, 5944 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 5945 case IPC_STAT: 5946 case MSG_STAT: 5947 case MSG_STAT_ANY: 5948 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 5949 break; 5950 case IPC_SET: 5951 perms = MSGQ__SETATTR; 5952 break; 5953 case IPC_RMID: 5954 perms = MSGQ__DESTROY; 5955 break; 5956 default: 5957 return 0; 5958 } 5959 5960 err = ipc_has_perm(msq, perms); 5961 return err; 5962 } 5963 5964 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 5965 { 5966 struct ipc_security_struct *isec; 5967 struct msg_security_struct *msec; 5968 struct common_audit_data ad; 5969 u32 sid = current_sid(); 5970 int rc; 5971 5972 isec = selinux_ipc(msq); 5973 msec = selinux_msg_msg(msg); 5974 5975 /* 5976 * First time through, need to assign label to the message 5977 */ 5978 if (msec->sid == SECINITSID_UNLABELED) { 5979 /* 5980 * Compute new sid based on current process and 5981 * message queue this message will be stored in 5982 */ 5983 rc = security_transition_sid(&selinux_state, sid, isec->sid, 5984 SECCLASS_MSG, NULL, &msec->sid); 5985 if (rc) 5986 return rc; 5987 } 5988 5989 ad.type = LSM_AUDIT_DATA_IPC; 5990 ad.u.ipc_id = msq->key; 5991 5992 /* Can this process write to the queue? */ 5993 rc = avc_has_perm(&selinux_state, 5994 sid, isec->sid, SECCLASS_MSGQ, 5995 MSGQ__WRITE, &ad); 5996 if (!rc) 5997 /* Can this process send the message */ 5998 rc = avc_has_perm(&selinux_state, 5999 sid, msec->sid, SECCLASS_MSG, 6000 MSG__SEND, &ad); 6001 if (!rc) 6002 /* Can the message be put in the queue? */ 6003 rc = avc_has_perm(&selinux_state, 6004 msec->sid, isec->sid, SECCLASS_MSGQ, 6005 MSGQ__ENQUEUE, &ad); 6006 6007 return rc; 6008 } 6009 6010 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6011 struct task_struct *target, 6012 long type, int mode) 6013 { 6014 struct ipc_security_struct *isec; 6015 struct msg_security_struct *msec; 6016 struct common_audit_data ad; 6017 u32 sid = task_sid(target); 6018 int rc; 6019 6020 isec = selinux_ipc(msq); 6021 msec = selinux_msg_msg(msg); 6022 6023 ad.type = LSM_AUDIT_DATA_IPC; 6024 ad.u.ipc_id = msq->key; 6025 6026 rc = avc_has_perm(&selinux_state, 6027 sid, isec->sid, 6028 SECCLASS_MSGQ, MSGQ__READ, &ad); 6029 if (!rc) 6030 rc = avc_has_perm(&selinux_state, 6031 sid, msec->sid, 6032 SECCLASS_MSG, MSG__RECEIVE, &ad); 6033 return rc; 6034 } 6035 6036 /* Shared Memory security operations */ 6037 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6038 { 6039 struct ipc_security_struct *isec; 6040 struct common_audit_data ad; 6041 u32 sid = current_sid(); 6042 int rc; 6043 6044 isec = selinux_ipc(shp); 6045 ipc_init_security(isec, SECCLASS_SHM); 6046 6047 ad.type = LSM_AUDIT_DATA_IPC; 6048 ad.u.ipc_id = shp->key; 6049 6050 rc = avc_has_perm(&selinux_state, 6051 sid, isec->sid, SECCLASS_SHM, 6052 SHM__CREATE, &ad); 6053 return rc; 6054 } 6055 6056 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6057 { 6058 struct ipc_security_struct *isec; 6059 struct common_audit_data ad; 6060 u32 sid = current_sid(); 6061 6062 isec = selinux_ipc(shp); 6063 6064 ad.type = LSM_AUDIT_DATA_IPC; 6065 ad.u.ipc_id = shp->key; 6066 6067 return avc_has_perm(&selinux_state, 6068 sid, isec->sid, SECCLASS_SHM, 6069 SHM__ASSOCIATE, &ad); 6070 } 6071 6072 /* Note, at this point, shp is locked down */ 6073 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6074 { 6075 int perms; 6076 int err; 6077 6078 switch (cmd) { 6079 case IPC_INFO: 6080 case SHM_INFO: 6081 /* No specific object, just general system-wide information. */ 6082 return avc_has_perm(&selinux_state, 6083 current_sid(), SECINITSID_KERNEL, 6084 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6085 case IPC_STAT: 6086 case SHM_STAT: 6087 case SHM_STAT_ANY: 6088 perms = SHM__GETATTR | SHM__ASSOCIATE; 6089 break; 6090 case IPC_SET: 6091 perms = SHM__SETATTR; 6092 break; 6093 case SHM_LOCK: 6094 case SHM_UNLOCK: 6095 perms = SHM__LOCK; 6096 break; 6097 case IPC_RMID: 6098 perms = SHM__DESTROY; 6099 break; 6100 default: 6101 return 0; 6102 } 6103 6104 err = ipc_has_perm(shp, perms); 6105 return err; 6106 } 6107 6108 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6109 char __user *shmaddr, int shmflg) 6110 { 6111 u32 perms; 6112 6113 if (shmflg & SHM_RDONLY) 6114 perms = SHM__READ; 6115 else 6116 perms = SHM__READ | SHM__WRITE; 6117 6118 return ipc_has_perm(shp, perms); 6119 } 6120 6121 /* Semaphore security operations */ 6122 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6123 { 6124 struct ipc_security_struct *isec; 6125 struct common_audit_data ad; 6126 u32 sid = current_sid(); 6127 int rc; 6128 6129 isec = selinux_ipc(sma); 6130 ipc_init_security(isec, SECCLASS_SEM); 6131 6132 ad.type = LSM_AUDIT_DATA_IPC; 6133 ad.u.ipc_id = sma->key; 6134 6135 rc = avc_has_perm(&selinux_state, 6136 sid, isec->sid, SECCLASS_SEM, 6137 SEM__CREATE, &ad); 6138 return rc; 6139 } 6140 6141 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6142 { 6143 struct ipc_security_struct *isec; 6144 struct common_audit_data ad; 6145 u32 sid = current_sid(); 6146 6147 isec = selinux_ipc(sma); 6148 6149 ad.type = LSM_AUDIT_DATA_IPC; 6150 ad.u.ipc_id = sma->key; 6151 6152 return avc_has_perm(&selinux_state, 6153 sid, isec->sid, SECCLASS_SEM, 6154 SEM__ASSOCIATE, &ad); 6155 } 6156 6157 /* Note, at this point, sma is locked down */ 6158 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6159 { 6160 int err; 6161 u32 perms; 6162 6163 switch (cmd) { 6164 case IPC_INFO: 6165 case SEM_INFO: 6166 /* No specific object, just general system-wide information. */ 6167 return avc_has_perm(&selinux_state, 6168 current_sid(), SECINITSID_KERNEL, 6169 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6170 case GETPID: 6171 case GETNCNT: 6172 case GETZCNT: 6173 perms = SEM__GETATTR; 6174 break; 6175 case GETVAL: 6176 case GETALL: 6177 perms = SEM__READ; 6178 break; 6179 case SETVAL: 6180 case SETALL: 6181 perms = SEM__WRITE; 6182 break; 6183 case IPC_RMID: 6184 perms = SEM__DESTROY; 6185 break; 6186 case IPC_SET: 6187 perms = SEM__SETATTR; 6188 break; 6189 case IPC_STAT: 6190 case SEM_STAT: 6191 case SEM_STAT_ANY: 6192 perms = SEM__GETATTR | SEM__ASSOCIATE; 6193 break; 6194 default: 6195 return 0; 6196 } 6197 6198 err = ipc_has_perm(sma, perms); 6199 return err; 6200 } 6201 6202 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6203 struct sembuf *sops, unsigned nsops, int alter) 6204 { 6205 u32 perms; 6206 6207 if (alter) 6208 perms = SEM__READ | SEM__WRITE; 6209 else 6210 perms = SEM__READ; 6211 6212 return ipc_has_perm(sma, perms); 6213 } 6214 6215 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6216 { 6217 u32 av = 0; 6218 6219 av = 0; 6220 if (flag & S_IRUGO) 6221 av |= IPC__UNIX_READ; 6222 if (flag & S_IWUGO) 6223 av |= IPC__UNIX_WRITE; 6224 6225 if (av == 0) 6226 return 0; 6227 6228 return ipc_has_perm(ipcp, av); 6229 } 6230 6231 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6232 { 6233 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6234 *secid = isec->sid; 6235 } 6236 6237 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6238 { 6239 if (inode) 6240 inode_doinit_with_dentry(inode, dentry); 6241 } 6242 6243 static int selinux_getprocattr(struct task_struct *p, 6244 char *name, char **value) 6245 { 6246 const struct task_security_struct *__tsec; 6247 u32 sid; 6248 int error; 6249 unsigned len; 6250 6251 rcu_read_lock(); 6252 __tsec = selinux_cred(__task_cred(p)); 6253 6254 if (current != p) { 6255 error = avc_has_perm(&selinux_state, 6256 current_sid(), __tsec->sid, 6257 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6258 if (error) 6259 goto bad; 6260 } 6261 6262 if (!strcmp(name, "current")) 6263 sid = __tsec->sid; 6264 else if (!strcmp(name, "prev")) 6265 sid = __tsec->osid; 6266 else if (!strcmp(name, "exec")) 6267 sid = __tsec->exec_sid; 6268 else if (!strcmp(name, "fscreate")) 6269 sid = __tsec->create_sid; 6270 else if (!strcmp(name, "keycreate")) 6271 sid = __tsec->keycreate_sid; 6272 else if (!strcmp(name, "sockcreate")) 6273 sid = __tsec->sockcreate_sid; 6274 else { 6275 error = -EINVAL; 6276 goto bad; 6277 } 6278 rcu_read_unlock(); 6279 6280 if (!sid) 6281 return 0; 6282 6283 error = security_sid_to_context(&selinux_state, sid, value, &len); 6284 if (error) 6285 return error; 6286 return len; 6287 6288 bad: 6289 rcu_read_unlock(); 6290 return error; 6291 } 6292 6293 static int selinux_setprocattr(const char *name, void *value, size_t size) 6294 { 6295 struct task_security_struct *tsec; 6296 struct cred *new; 6297 u32 mysid = current_sid(), sid = 0, ptsid; 6298 int error; 6299 char *str = value; 6300 6301 /* 6302 * Basic control over ability to set these attributes at all. 6303 */ 6304 if (!strcmp(name, "exec")) 6305 error = avc_has_perm(&selinux_state, 6306 mysid, mysid, SECCLASS_PROCESS, 6307 PROCESS__SETEXEC, NULL); 6308 else if (!strcmp(name, "fscreate")) 6309 error = avc_has_perm(&selinux_state, 6310 mysid, mysid, SECCLASS_PROCESS, 6311 PROCESS__SETFSCREATE, NULL); 6312 else if (!strcmp(name, "keycreate")) 6313 error = avc_has_perm(&selinux_state, 6314 mysid, mysid, SECCLASS_PROCESS, 6315 PROCESS__SETKEYCREATE, NULL); 6316 else if (!strcmp(name, "sockcreate")) 6317 error = avc_has_perm(&selinux_state, 6318 mysid, mysid, SECCLASS_PROCESS, 6319 PROCESS__SETSOCKCREATE, NULL); 6320 else if (!strcmp(name, "current")) 6321 error = avc_has_perm(&selinux_state, 6322 mysid, mysid, SECCLASS_PROCESS, 6323 PROCESS__SETCURRENT, NULL); 6324 else 6325 error = -EINVAL; 6326 if (error) 6327 return error; 6328 6329 /* Obtain a SID for the context, if one was specified. */ 6330 if (size && str[0] && str[0] != '\n') { 6331 if (str[size-1] == '\n') { 6332 str[size-1] = 0; 6333 size--; 6334 } 6335 error = security_context_to_sid(&selinux_state, value, size, 6336 &sid, GFP_KERNEL); 6337 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6338 if (!has_cap_mac_admin(true)) { 6339 struct audit_buffer *ab; 6340 size_t audit_size; 6341 6342 /* We strip a nul only if it is at the end, otherwise the 6343 * context contains a nul and we should audit that */ 6344 if (str[size - 1] == '\0') 6345 audit_size = size - 1; 6346 else 6347 audit_size = size; 6348 ab = audit_log_start(audit_context(), 6349 GFP_ATOMIC, 6350 AUDIT_SELINUX_ERR); 6351 audit_log_format(ab, "op=fscreate invalid_context="); 6352 audit_log_n_untrustedstring(ab, value, audit_size); 6353 audit_log_end(ab); 6354 6355 return error; 6356 } 6357 error = security_context_to_sid_force( 6358 &selinux_state, 6359 value, size, &sid); 6360 } 6361 if (error) 6362 return error; 6363 } 6364 6365 new = prepare_creds(); 6366 if (!new) 6367 return -ENOMEM; 6368 6369 /* Permission checking based on the specified context is 6370 performed during the actual operation (execve, 6371 open/mkdir/...), when we know the full context of the 6372 operation. See selinux_bprm_set_creds for the execve 6373 checks and may_create for the file creation checks. The 6374 operation will then fail if the context is not permitted. */ 6375 tsec = selinux_cred(new); 6376 if (!strcmp(name, "exec")) { 6377 tsec->exec_sid = sid; 6378 } else if (!strcmp(name, "fscreate")) { 6379 tsec->create_sid = sid; 6380 } else if (!strcmp(name, "keycreate")) { 6381 if (sid) { 6382 error = avc_has_perm(&selinux_state, mysid, sid, 6383 SECCLASS_KEY, KEY__CREATE, NULL); 6384 if (error) 6385 goto abort_change; 6386 } 6387 tsec->keycreate_sid = sid; 6388 } else if (!strcmp(name, "sockcreate")) { 6389 tsec->sockcreate_sid = sid; 6390 } else if (!strcmp(name, "current")) { 6391 error = -EINVAL; 6392 if (sid == 0) 6393 goto abort_change; 6394 6395 /* Only allow single threaded processes to change context */ 6396 error = -EPERM; 6397 if (!current_is_single_threaded()) { 6398 error = security_bounded_transition(&selinux_state, 6399 tsec->sid, sid); 6400 if (error) 6401 goto abort_change; 6402 } 6403 6404 /* Check permissions for the transition. */ 6405 error = avc_has_perm(&selinux_state, 6406 tsec->sid, sid, SECCLASS_PROCESS, 6407 PROCESS__DYNTRANSITION, NULL); 6408 if (error) 6409 goto abort_change; 6410 6411 /* Check for ptracing, and update the task SID if ok. 6412 Otherwise, leave SID unchanged and fail. */ 6413 ptsid = ptrace_parent_sid(); 6414 if (ptsid != 0) { 6415 error = avc_has_perm(&selinux_state, 6416 ptsid, sid, SECCLASS_PROCESS, 6417 PROCESS__PTRACE, NULL); 6418 if (error) 6419 goto abort_change; 6420 } 6421 6422 tsec->sid = sid; 6423 } else { 6424 error = -EINVAL; 6425 goto abort_change; 6426 } 6427 6428 commit_creds(new); 6429 return size; 6430 6431 abort_change: 6432 abort_creds(new); 6433 return error; 6434 } 6435 6436 static int selinux_ismaclabel(const char *name) 6437 { 6438 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6439 } 6440 6441 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6442 { 6443 return security_sid_to_context(&selinux_state, secid, 6444 secdata, seclen); 6445 } 6446 6447 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6448 { 6449 return security_context_to_sid(&selinux_state, secdata, seclen, 6450 secid, GFP_KERNEL); 6451 } 6452 6453 static void selinux_release_secctx(char *secdata, u32 seclen) 6454 { 6455 kfree(secdata); 6456 } 6457 6458 static void selinux_inode_invalidate_secctx(struct inode *inode) 6459 { 6460 struct inode_security_struct *isec = selinux_inode(inode); 6461 6462 spin_lock(&isec->lock); 6463 isec->initialized = LABEL_INVALID; 6464 spin_unlock(&isec->lock); 6465 } 6466 6467 /* 6468 * called with inode->i_mutex locked 6469 */ 6470 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6471 { 6472 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6473 ctx, ctxlen, 0); 6474 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6475 return rc == -EOPNOTSUPP ? 0 : rc; 6476 } 6477 6478 /* 6479 * called with inode->i_mutex locked 6480 */ 6481 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6482 { 6483 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 6484 } 6485 6486 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6487 { 6488 int len = 0; 6489 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 6490 ctx, true); 6491 if (len < 0) 6492 return len; 6493 *ctxlen = len; 6494 return 0; 6495 } 6496 #ifdef CONFIG_KEYS 6497 6498 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6499 unsigned long flags) 6500 { 6501 const struct task_security_struct *tsec; 6502 struct key_security_struct *ksec; 6503 6504 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6505 if (!ksec) 6506 return -ENOMEM; 6507 6508 tsec = selinux_cred(cred); 6509 if (tsec->keycreate_sid) 6510 ksec->sid = tsec->keycreate_sid; 6511 else 6512 ksec->sid = tsec->sid; 6513 6514 k->security = ksec; 6515 return 0; 6516 } 6517 6518 static void selinux_key_free(struct key *k) 6519 { 6520 struct key_security_struct *ksec = k->security; 6521 6522 k->security = NULL; 6523 kfree(ksec); 6524 } 6525 6526 static int selinux_key_permission(key_ref_t key_ref, 6527 const struct cred *cred, 6528 unsigned perm) 6529 { 6530 struct key *key; 6531 struct key_security_struct *ksec; 6532 u32 sid; 6533 6534 /* if no specific permissions are requested, we skip the 6535 permission check. No serious, additional covert channels 6536 appear to be created. */ 6537 if (perm == 0) 6538 return 0; 6539 6540 sid = cred_sid(cred); 6541 6542 key = key_ref_to_ptr(key_ref); 6543 ksec = key->security; 6544 6545 return avc_has_perm(&selinux_state, 6546 sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6547 } 6548 6549 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6550 { 6551 struct key_security_struct *ksec = key->security; 6552 char *context = NULL; 6553 unsigned len; 6554 int rc; 6555 6556 rc = security_sid_to_context(&selinux_state, ksec->sid, 6557 &context, &len); 6558 if (!rc) 6559 rc = len; 6560 *_buffer = context; 6561 return rc; 6562 } 6563 #endif 6564 6565 #ifdef CONFIG_SECURITY_INFINIBAND 6566 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6567 { 6568 struct common_audit_data ad; 6569 int err; 6570 u32 sid = 0; 6571 struct ib_security_struct *sec = ib_sec; 6572 struct lsm_ibpkey_audit ibpkey; 6573 6574 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6575 if (err) 6576 return err; 6577 6578 ad.type = LSM_AUDIT_DATA_IBPKEY; 6579 ibpkey.subnet_prefix = subnet_prefix; 6580 ibpkey.pkey = pkey_val; 6581 ad.u.ibpkey = &ibpkey; 6582 return avc_has_perm(&selinux_state, 6583 sec->sid, sid, 6584 SECCLASS_INFINIBAND_PKEY, 6585 INFINIBAND_PKEY__ACCESS, &ad); 6586 } 6587 6588 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6589 u8 port_num) 6590 { 6591 struct common_audit_data ad; 6592 int err; 6593 u32 sid = 0; 6594 struct ib_security_struct *sec = ib_sec; 6595 struct lsm_ibendport_audit ibendport; 6596 6597 err = security_ib_endport_sid(&selinux_state, dev_name, port_num, 6598 &sid); 6599 6600 if (err) 6601 return err; 6602 6603 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6604 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name)); 6605 ibendport.port = port_num; 6606 ad.u.ibendport = &ibendport; 6607 return avc_has_perm(&selinux_state, 6608 sec->sid, sid, 6609 SECCLASS_INFINIBAND_ENDPORT, 6610 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6611 } 6612 6613 static int selinux_ib_alloc_security(void **ib_sec) 6614 { 6615 struct ib_security_struct *sec; 6616 6617 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6618 if (!sec) 6619 return -ENOMEM; 6620 sec->sid = current_sid(); 6621 6622 *ib_sec = sec; 6623 return 0; 6624 } 6625 6626 static void selinux_ib_free_security(void *ib_sec) 6627 { 6628 kfree(ib_sec); 6629 } 6630 #endif 6631 6632 #ifdef CONFIG_BPF_SYSCALL 6633 static int selinux_bpf(int cmd, union bpf_attr *attr, 6634 unsigned int size) 6635 { 6636 u32 sid = current_sid(); 6637 int ret; 6638 6639 switch (cmd) { 6640 case BPF_MAP_CREATE: 6641 ret = avc_has_perm(&selinux_state, 6642 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6643 NULL); 6644 break; 6645 case BPF_PROG_LOAD: 6646 ret = avc_has_perm(&selinux_state, 6647 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6648 NULL); 6649 break; 6650 default: 6651 ret = 0; 6652 break; 6653 } 6654 6655 return ret; 6656 } 6657 6658 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6659 { 6660 u32 av = 0; 6661 6662 if (fmode & FMODE_READ) 6663 av |= BPF__MAP_READ; 6664 if (fmode & FMODE_WRITE) 6665 av |= BPF__MAP_WRITE; 6666 return av; 6667 } 6668 6669 /* This function will check the file pass through unix socket or binder to see 6670 * if it is a bpf related object. And apply correspinding checks on the bpf 6671 * object based on the type. The bpf maps and programs, not like other files and 6672 * socket, are using a shared anonymous inode inside the kernel as their inode. 6673 * So checking that inode cannot identify if the process have privilege to 6674 * access the bpf object and that's why we have to add this additional check in 6675 * selinux_file_receive and selinux_binder_transfer_files. 6676 */ 6677 static int bpf_fd_pass(struct file *file, u32 sid) 6678 { 6679 struct bpf_security_struct *bpfsec; 6680 struct bpf_prog *prog; 6681 struct bpf_map *map; 6682 int ret; 6683 6684 if (file->f_op == &bpf_map_fops) { 6685 map = file->private_data; 6686 bpfsec = map->security; 6687 ret = avc_has_perm(&selinux_state, 6688 sid, bpfsec->sid, SECCLASS_BPF, 6689 bpf_map_fmode_to_av(file->f_mode), NULL); 6690 if (ret) 6691 return ret; 6692 } else if (file->f_op == &bpf_prog_fops) { 6693 prog = file->private_data; 6694 bpfsec = prog->aux->security; 6695 ret = avc_has_perm(&selinux_state, 6696 sid, bpfsec->sid, SECCLASS_BPF, 6697 BPF__PROG_RUN, NULL); 6698 if (ret) 6699 return ret; 6700 } 6701 return 0; 6702 } 6703 6704 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6705 { 6706 u32 sid = current_sid(); 6707 struct bpf_security_struct *bpfsec; 6708 6709 bpfsec = map->security; 6710 return avc_has_perm(&selinux_state, 6711 sid, bpfsec->sid, SECCLASS_BPF, 6712 bpf_map_fmode_to_av(fmode), NULL); 6713 } 6714 6715 static int selinux_bpf_prog(struct bpf_prog *prog) 6716 { 6717 u32 sid = current_sid(); 6718 struct bpf_security_struct *bpfsec; 6719 6720 bpfsec = prog->aux->security; 6721 return avc_has_perm(&selinux_state, 6722 sid, bpfsec->sid, SECCLASS_BPF, 6723 BPF__PROG_RUN, NULL); 6724 } 6725 6726 static int selinux_bpf_map_alloc(struct bpf_map *map) 6727 { 6728 struct bpf_security_struct *bpfsec; 6729 6730 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6731 if (!bpfsec) 6732 return -ENOMEM; 6733 6734 bpfsec->sid = current_sid(); 6735 map->security = bpfsec; 6736 6737 return 0; 6738 } 6739 6740 static void selinux_bpf_map_free(struct bpf_map *map) 6741 { 6742 struct bpf_security_struct *bpfsec = map->security; 6743 6744 map->security = NULL; 6745 kfree(bpfsec); 6746 } 6747 6748 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6749 { 6750 struct bpf_security_struct *bpfsec; 6751 6752 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6753 if (!bpfsec) 6754 return -ENOMEM; 6755 6756 bpfsec->sid = current_sid(); 6757 aux->security = bpfsec; 6758 6759 return 0; 6760 } 6761 6762 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6763 { 6764 struct bpf_security_struct *bpfsec = aux->security; 6765 6766 aux->security = NULL; 6767 kfree(bpfsec); 6768 } 6769 #endif 6770 6771 static int selinux_lockdown(enum lockdown_reason what) 6772 { 6773 struct common_audit_data ad; 6774 u32 sid = current_sid(); 6775 int invalid_reason = (what <= LOCKDOWN_NONE) || 6776 (what == LOCKDOWN_INTEGRITY_MAX) || 6777 (what >= LOCKDOWN_CONFIDENTIALITY_MAX); 6778 6779 if (WARN(invalid_reason, "Invalid lockdown reason")) { 6780 audit_log(audit_context(), 6781 GFP_ATOMIC, AUDIT_SELINUX_ERR, 6782 "lockdown_reason=invalid"); 6783 return -EINVAL; 6784 } 6785 6786 ad.type = LSM_AUDIT_DATA_LOCKDOWN; 6787 ad.u.reason = what; 6788 6789 if (what <= LOCKDOWN_INTEGRITY_MAX) 6790 return avc_has_perm(&selinux_state, 6791 sid, sid, SECCLASS_LOCKDOWN, 6792 LOCKDOWN__INTEGRITY, &ad); 6793 else 6794 return avc_has_perm(&selinux_state, 6795 sid, sid, SECCLASS_LOCKDOWN, 6796 LOCKDOWN__CONFIDENTIALITY, &ad); 6797 } 6798 6799 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = { 6800 .lbs_cred = sizeof(struct task_security_struct), 6801 .lbs_file = sizeof(struct file_security_struct), 6802 .lbs_inode = sizeof(struct inode_security_struct), 6803 .lbs_ipc = sizeof(struct ipc_security_struct), 6804 .lbs_msg_msg = sizeof(struct msg_security_struct), 6805 }; 6806 6807 #ifdef CONFIG_PERF_EVENTS 6808 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6809 { 6810 u32 requested, sid = current_sid(); 6811 6812 if (type == PERF_SECURITY_OPEN) 6813 requested = PERF_EVENT__OPEN; 6814 else if (type == PERF_SECURITY_CPU) 6815 requested = PERF_EVENT__CPU; 6816 else if (type == PERF_SECURITY_KERNEL) 6817 requested = PERF_EVENT__KERNEL; 6818 else if (type == PERF_SECURITY_TRACEPOINT) 6819 requested = PERF_EVENT__TRACEPOINT; 6820 else 6821 return -EINVAL; 6822 6823 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT, 6824 requested, NULL); 6825 } 6826 6827 static int selinux_perf_event_alloc(struct perf_event *event) 6828 { 6829 struct perf_event_security_struct *perfsec; 6830 6831 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6832 if (!perfsec) 6833 return -ENOMEM; 6834 6835 perfsec->sid = current_sid(); 6836 event->security = perfsec; 6837 6838 return 0; 6839 } 6840 6841 static void selinux_perf_event_free(struct perf_event *event) 6842 { 6843 struct perf_event_security_struct *perfsec = event->security; 6844 6845 event->security = NULL; 6846 kfree(perfsec); 6847 } 6848 6849 static int selinux_perf_event_read(struct perf_event *event) 6850 { 6851 struct perf_event_security_struct *perfsec = event->security; 6852 u32 sid = current_sid(); 6853 6854 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6855 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6856 } 6857 6858 static int selinux_perf_event_write(struct perf_event *event) 6859 { 6860 struct perf_event_security_struct *perfsec = event->security; 6861 u32 sid = current_sid(); 6862 6863 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6864 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6865 } 6866 #endif 6867 6868 /* 6869 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6870 * 1. any hooks that don't belong to (2.) or (3.) below, 6871 * 2. hooks that both access structures allocated by other hooks, and allocate 6872 * structures that can be later accessed by other hooks (mostly "cloning" 6873 * hooks), 6874 * 3. hooks that only allocate structures that can be later accessed by other 6875 * hooks ("allocating" hooks). 6876 * 6877 * Please follow block comment delimiters in the list to keep this order. 6878 * 6879 * This ordering is needed for SELinux runtime disable to work at least somewhat 6880 * safely. Breaking the ordering rules above might lead to NULL pointer derefs 6881 * when disabling SELinux at runtime. 6882 */ 6883 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { 6884 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6885 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6886 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6887 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6888 6889 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6890 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6891 LSM_HOOK_INIT(capget, selinux_capget), 6892 LSM_HOOK_INIT(capset, selinux_capset), 6893 LSM_HOOK_INIT(capable, selinux_capable), 6894 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6895 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6896 LSM_HOOK_INIT(syslog, selinux_syslog), 6897 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6898 6899 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6900 6901 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds), 6902 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6903 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6904 6905 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), 6906 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 6907 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6908 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6909 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6910 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6911 LSM_HOOK_INIT(sb_mount, selinux_mount), 6912 LSM_HOOK_INIT(sb_umount, selinux_umount), 6913 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6914 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6915 6916 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6917 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 6918 6919 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 6920 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 6921 LSM_HOOK_INIT(inode_create, selinux_inode_create), 6922 LSM_HOOK_INIT(inode_link, selinux_inode_link), 6923 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 6924 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 6925 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 6926 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 6927 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 6928 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 6929 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 6930 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 6931 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 6932 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 6933 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 6934 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 6935 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 6936 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 6937 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 6938 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 6939 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 6940 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 6941 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 6942 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 6943 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 6944 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 6945 LSM_HOOK_INIT(path_notify, selinux_path_notify), 6946 6947 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 6948 6949 LSM_HOOK_INIT(file_permission, selinux_file_permission), 6950 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 6951 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 6952 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 6953 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 6954 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 6955 LSM_HOOK_INIT(file_lock, selinux_file_lock), 6956 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 6957 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 6958 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 6959 LSM_HOOK_INIT(file_receive, selinux_file_receive), 6960 6961 LSM_HOOK_INIT(file_open, selinux_file_open), 6962 6963 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 6964 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 6965 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 6966 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 6967 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 6968 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 6969 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 6970 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 6971 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 6972 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 6973 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 6974 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 6975 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), 6976 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 6977 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 6978 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 6979 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 6980 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 6981 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 6982 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 6983 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 6984 LSM_HOOK_INIT(task_kill, selinux_task_kill), 6985 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 6986 6987 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 6988 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 6989 6990 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 6991 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 6992 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 6993 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 6994 6995 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 6996 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 6997 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 6998 6999 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7000 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7001 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7002 7003 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7004 7005 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7006 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7007 7008 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7009 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7010 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7011 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7012 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7013 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7014 7015 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7016 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7017 7018 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7019 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7020 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7021 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7022 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7023 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7024 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7025 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7026 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7027 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7028 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7029 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7030 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7031 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7032 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7033 LSM_HOOK_INIT(socket_getpeersec_stream, 7034 selinux_socket_getpeersec_stream), 7035 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7036 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7037 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7038 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7039 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7040 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7041 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7042 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7043 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7044 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7045 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7046 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7047 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7048 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7049 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7050 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7051 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7052 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7053 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7054 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7055 #ifdef CONFIG_SECURITY_INFINIBAND 7056 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7057 LSM_HOOK_INIT(ib_endport_manage_subnet, 7058 selinux_ib_endport_manage_subnet), 7059 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7060 #endif 7061 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7062 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7063 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7064 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7065 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7066 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7067 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7068 selinux_xfrm_state_pol_flow_match), 7069 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7070 #endif 7071 7072 #ifdef CONFIG_KEYS 7073 LSM_HOOK_INIT(key_free, selinux_key_free), 7074 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7075 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7076 #endif 7077 7078 #ifdef CONFIG_AUDIT 7079 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7080 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7081 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7082 #endif 7083 7084 #ifdef CONFIG_BPF_SYSCALL 7085 LSM_HOOK_INIT(bpf, selinux_bpf), 7086 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7087 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7088 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7089 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7090 #endif 7091 7092 #ifdef CONFIG_PERF_EVENTS 7093 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7094 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7095 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7096 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7097 #endif 7098 7099 LSM_HOOK_INIT(locked_down, selinux_lockdown), 7100 7101 /* 7102 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7103 */ 7104 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7105 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7106 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7107 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt), 7108 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7109 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7110 #endif 7111 7112 /* 7113 * PUT "ALLOCATING" HOOKS HERE 7114 */ 7115 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7116 LSM_HOOK_INIT(msg_queue_alloc_security, 7117 selinux_msg_queue_alloc_security), 7118 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7119 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7120 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7121 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7122 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7123 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7124 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7125 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7126 #ifdef CONFIG_SECURITY_INFINIBAND 7127 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7128 #endif 7129 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7130 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7131 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7132 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7133 selinux_xfrm_state_alloc_acquire), 7134 #endif 7135 #ifdef CONFIG_KEYS 7136 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7137 #endif 7138 #ifdef CONFIG_AUDIT 7139 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7140 #endif 7141 #ifdef CONFIG_BPF_SYSCALL 7142 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7143 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7144 #endif 7145 #ifdef CONFIG_PERF_EVENTS 7146 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7147 #endif 7148 }; 7149 7150 static __init int selinux_init(void) 7151 { 7152 pr_info("SELinux: Initializing.\n"); 7153 7154 memset(&selinux_state, 0, sizeof(selinux_state)); 7155 enforcing_set(&selinux_state, selinux_enforcing_boot); 7156 selinux_state.checkreqprot = selinux_checkreqprot_boot; 7157 selinux_ss_init(&selinux_state.ss); 7158 selinux_avc_init(&selinux_state.avc); 7159 7160 /* Set the security state for the initial task. */ 7161 cred_init_security(); 7162 7163 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7164 7165 avc_init(); 7166 7167 avtab_cache_init(); 7168 7169 ebitmap_cache_init(); 7170 7171 hashtab_cache_init(); 7172 7173 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7174 7175 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7176 panic("SELinux: Unable to register AVC netcache callback\n"); 7177 7178 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7179 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7180 7181 if (selinux_enforcing_boot) 7182 pr_debug("SELinux: Starting in enforcing mode\n"); 7183 else 7184 pr_debug("SELinux: Starting in permissive mode\n"); 7185 7186 fs_validate_description(&selinux_fs_parameters); 7187 7188 return 0; 7189 } 7190 7191 static void delayed_superblock_init(struct super_block *sb, void *unused) 7192 { 7193 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7194 } 7195 7196 void selinux_complete_init(void) 7197 { 7198 pr_debug("SELinux: Completing initialization.\n"); 7199 7200 /* Set up any superblocks initialized prior to the policy load. */ 7201 pr_debug("SELinux: Setting up existing superblocks.\n"); 7202 iterate_supers(delayed_superblock_init, NULL); 7203 } 7204 7205 /* SELinux requires early initialization in order to label 7206 all processes and objects when they are created. */ 7207 DEFINE_LSM(selinux) = { 7208 .name = "selinux", 7209 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7210 .enabled = &selinux_enabled_boot, 7211 .blobs = &selinux_blob_sizes, 7212 .init = selinux_init, 7213 }; 7214 7215 #if defined(CONFIG_NETFILTER) 7216 7217 static const struct nf_hook_ops selinux_nf_ops[] = { 7218 { 7219 .hook = selinux_ipv4_postroute, 7220 .pf = NFPROTO_IPV4, 7221 .hooknum = NF_INET_POST_ROUTING, 7222 .priority = NF_IP_PRI_SELINUX_LAST, 7223 }, 7224 { 7225 .hook = selinux_ipv4_forward, 7226 .pf = NFPROTO_IPV4, 7227 .hooknum = NF_INET_FORWARD, 7228 .priority = NF_IP_PRI_SELINUX_FIRST, 7229 }, 7230 { 7231 .hook = selinux_ipv4_output, 7232 .pf = NFPROTO_IPV4, 7233 .hooknum = NF_INET_LOCAL_OUT, 7234 .priority = NF_IP_PRI_SELINUX_FIRST, 7235 }, 7236 #if IS_ENABLED(CONFIG_IPV6) 7237 { 7238 .hook = selinux_ipv6_postroute, 7239 .pf = NFPROTO_IPV6, 7240 .hooknum = NF_INET_POST_ROUTING, 7241 .priority = NF_IP6_PRI_SELINUX_LAST, 7242 }, 7243 { 7244 .hook = selinux_ipv6_forward, 7245 .pf = NFPROTO_IPV6, 7246 .hooknum = NF_INET_FORWARD, 7247 .priority = NF_IP6_PRI_SELINUX_FIRST, 7248 }, 7249 { 7250 .hook = selinux_ipv6_output, 7251 .pf = NFPROTO_IPV6, 7252 .hooknum = NF_INET_LOCAL_OUT, 7253 .priority = NF_IP6_PRI_SELINUX_FIRST, 7254 }, 7255 #endif /* IPV6 */ 7256 }; 7257 7258 static int __net_init selinux_nf_register(struct net *net) 7259 { 7260 return nf_register_net_hooks(net, selinux_nf_ops, 7261 ARRAY_SIZE(selinux_nf_ops)); 7262 } 7263 7264 static void __net_exit selinux_nf_unregister(struct net *net) 7265 { 7266 nf_unregister_net_hooks(net, selinux_nf_ops, 7267 ARRAY_SIZE(selinux_nf_ops)); 7268 } 7269 7270 static struct pernet_operations selinux_net_ops = { 7271 .init = selinux_nf_register, 7272 .exit = selinux_nf_unregister, 7273 }; 7274 7275 static int __init selinux_nf_ip_init(void) 7276 { 7277 int err; 7278 7279 if (!selinux_enabled_boot) 7280 return 0; 7281 7282 pr_debug("SELinux: Registering netfilter hooks\n"); 7283 7284 err = register_pernet_subsys(&selinux_net_ops); 7285 if (err) 7286 panic("SELinux: register_pernet_subsys: error %d\n", err); 7287 7288 return 0; 7289 } 7290 __initcall(selinux_nf_ip_init); 7291 7292 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7293 static void selinux_nf_ip_exit(void) 7294 { 7295 pr_debug("SELinux: Unregistering netfilter hooks\n"); 7296 7297 unregister_pernet_subsys(&selinux_net_ops); 7298 } 7299 #endif 7300 7301 #else /* CONFIG_NETFILTER */ 7302 7303 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7304 #define selinux_nf_ip_exit() 7305 #endif 7306 7307 #endif /* CONFIG_NETFILTER */ 7308 7309 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7310 int selinux_disable(struct selinux_state *state) 7311 { 7312 if (selinux_initialized(state)) { 7313 /* Not permitted after initial policy load. */ 7314 return -EINVAL; 7315 } 7316 7317 if (selinux_disabled(state)) { 7318 /* Only do this once. */ 7319 return -EINVAL; 7320 } 7321 7322 selinux_mark_disabled(state); 7323 7324 pr_info("SELinux: Disabled at runtime.\n"); 7325 7326 /* 7327 * Unregister netfilter hooks. 7328 * Must be done before security_delete_hooks() to avoid breaking 7329 * runtime disable. 7330 */ 7331 selinux_nf_ip_exit(); 7332 7333 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 7334 7335 /* Try to destroy the avc node cache */ 7336 avc_disable(); 7337 7338 /* Unregister selinuxfs. */ 7339 exit_sel_fs(); 7340 7341 return 0; 7342 } 7343 #endif 7344