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 if (checkreqprot) 148 pr_warn("SELinux: checkreqprot set to 1 via kernel parameter. This is deprecated and will be rejected in a future kernel release.\n"); 149 } 150 return 1; 151 } 152 __setup("checkreqprot=", checkreqprot_setup); 153 154 /** 155 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 156 * 157 * Description: 158 * This function checks the SECMARK reference counter to see if any SECMARK 159 * targets are currently configured, if the reference counter is greater than 160 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 161 * enabled, false (0) if SECMARK is disabled. If the always_check_network 162 * policy capability is enabled, SECMARK is always considered enabled. 163 * 164 */ 165 static int selinux_secmark_enabled(void) 166 { 167 return (selinux_policycap_alwaysnetwork() || 168 atomic_read(&selinux_secmark_refcount)); 169 } 170 171 /** 172 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 173 * 174 * Description: 175 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 176 * (1) if any are enabled or false (0) if neither are enabled. If the 177 * always_check_network policy capability is enabled, peer labeling 178 * is always considered enabled. 179 * 180 */ 181 static int selinux_peerlbl_enabled(void) 182 { 183 return (selinux_policycap_alwaysnetwork() || 184 netlbl_enabled() || selinux_xfrm_enabled()); 185 } 186 187 static int selinux_netcache_avc_callback(u32 event) 188 { 189 if (event == AVC_CALLBACK_RESET) { 190 sel_netif_flush(); 191 sel_netnode_flush(); 192 sel_netport_flush(); 193 synchronize_net(); 194 } 195 return 0; 196 } 197 198 static int selinux_lsm_notifier_avc_callback(u32 event) 199 { 200 if (event == AVC_CALLBACK_RESET) { 201 sel_ib_pkey_flush(); 202 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 203 } 204 205 return 0; 206 } 207 208 /* 209 * initialise the security for the init task 210 */ 211 static void cred_init_security(void) 212 { 213 struct cred *cred = (struct cred *) current->real_cred; 214 struct task_security_struct *tsec; 215 216 tsec = selinux_cred(cred); 217 tsec->osid = tsec->sid = SECINITSID_KERNEL; 218 } 219 220 /* 221 * get the security ID of a set of credentials 222 */ 223 static inline u32 cred_sid(const struct cred *cred) 224 { 225 const struct task_security_struct *tsec; 226 227 tsec = selinux_cred(cred); 228 return tsec->sid; 229 } 230 231 /* 232 * get the objective security ID of a task 233 */ 234 static inline u32 task_sid(const struct task_struct *task) 235 { 236 u32 sid; 237 238 rcu_read_lock(); 239 sid = cred_sid(__task_cred(task)); 240 rcu_read_unlock(); 241 return sid; 242 } 243 244 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 245 246 /* 247 * Try reloading inode security labels that have been marked as invalid. The 248 * @may_sleep parameter indicates when sleeping and thus reloading labels is 249 * allowed; when set to false, returns -ECHILD when the label is 250 * invalid. The @dentry parameter should be set to a dentry of the inode. 251 */ 252 static int __inode_security_revalidate(struct inode *inode, 253 struct dentry *dentry, 254 bool may_sleep) 255 { 256 struct inode_security_struct *isec = selinux_inode(inode); 257 258 might_sleep_if(may_sleep); 259 260 if (selinux_initialized(&selinux_state) && 261 isec->initialized != LABEL_INITIALIZED) { 262 if (!may_sleep) 263 return -ECHILD; 264 265 /* 266 * Try reloading the inode security label. This will fail if 267 * @opt_dentry is NULL and no dentry for this inode can be 268 * found; in that case, continue using the old label. 269 */ 270 inode_doinit_with_dentry(inode, dentry); 271 } 272 return 0; 273 } 274 275 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 276 { 277 return selinux_inode(inode); 278 } 279 280 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 281 { 282 int error; 283 284 error = __inode_security_revalidate(inode, NULL, !rcu); 285 if (error) 286 return ERR_PTR(error); 287 return selinux_inode(inode); 288 } 289 290 /* 291 * Get the security label of an inode. 292 */ 293 static struct inode_security_struct *inode_security(struct inode *inode) 294 { 295 __inode_security_revalidate(inode, NULL, true); 296 return selinux_inode(inode); 297 } 298 299 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 300 { 301 struct inode *inode = d_backing_inode(dentry); 302 303 return selinux_inode(inode); 304 } 305 306 /* 307 * Get the security label of a dentry's backing inode. 308 */ 309 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 310 { 311 struct inode *inode = d_backing_inode(dentry); 312 313 __inode_security_revalidate(inode, dentry, true); 314 return selinux_inode(inode); 315 } 316 317 static void inode_free_security(struct inode *inode) 318 { 319 struct inode_security_struct *isec = selinux_inode(inode); 320 struct superblock_security_struct *sbsec; 321 322 if (!isec) 323 return; 324 sbsec = inode->i_sb->s_security; 325 /* 326 * As not all inode security structures are in a list, we check for 327 * empty list outside of the lock to make sure that we won't waste 328 * time taking a lock doing nothing. 329 * 330 * The list_del_init() function can be safely called more than once. 331 * It should not be possible for this function to be called with 332 * concurrent list_add(), but for better safety against future changes 333 * in the code, we use list_empty_careful() here. 334 */ 335 if (!list_empty_careful(&isec->list)) { 336 spin_lock(&sbsec->isec_lock); 337 list_del_init(&isec->list); 338 spin_unlock(&sbsec->isec_lock); 339 } 340 } 341 342 static void superblock_free_security(struct super_block *sb) 343 { 344 struct superblock_security_struct *sbsec = sb->s_security; 345 sb->s_security = NULL; 346 kfree(sbsec); 347 } 348 349 struct selinux_mnt_opts { 350 const char *fscontext, *context, *rootcontext, *defcontext; 351 }; 352 353 static void selinux_free_mnt_opts(void *mnt_opts) 354 { 355 struct selinux_mnt_opts *opts = mnt_opts; 356 kfree(opts->fscontext); 357 kfree(opts->context); 358 kfree(opts->rootcontext); 359 kfree(opts->defcontext); 360 kfree(opts); 361 } 362 363 enum { 364 Opt_error = -1, 365 Opt_context = 0, 366 Opt_defcontext = 1, 367 Opt_fscontext = 2, 368 Opt_rootcontext = 3, 369 Opt_seclabel = 4, 370 }; 371 372 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 373 static struct { 374 const char *name; 375 int len; 376 int opt; 377 bool has_arg; 378 } tokens[] = { 379 A(context, true), 380 A(fscontext, true), 381 A(defcontext, true), 382 A(rootcontext, true), 383 A(seclabel, false), 384 }; 385 #undef A 386 387 static int match_opt_prefix(char *s, int l, char **arg) 388 { 389 int i; 390 391 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 392 size_t len = tokens[i].len; 393 if (len > l || memcmp(s, tokens[i].name, len)) 394 continue; 395 if (tokens[i].has_arg) { 396 if (len == l || s[len] != '=') 397 continue; 398 *arg = s + len + 1; 399 } else if (len != l) 400 continue; 401 return tokens[i].opt; 402 } 403 return Opt_error; 404 } 405 406 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 407 408 static int may_context_mount_sb_relabel(u32 sid, 409 struct superblock_security_struct *sbsec, 410 const struct cred *cred) 411 { 412 const struct task_security_struct *tsec = selinux_cred(cred); 413 int rc; 414 415 rc = avc_has_perm(&selinux_state, 416 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 417 FILESYSTEM__RELABELFROM, NULL); 418 if (rc) 419 return rc; 420 421 rc = avc_has_perm(&selinux_state, 422 tsec->sid, sid, SECCLASS_FILESYSTEM, 423 FILESYSTEM__RELABELTO, NULL); 424 return rc; 425 } 426 427 static int may_context_mount_inode_relabel(u32 sid, 428 struct superblock_security_struct *sbsec, 429 const struct cred *cred) 430 { 431 const struct task_security_struct *tsec = selinux_cred(cred); 432 int rc; 433 rc = avc_has_perm(&selinux_state, 434 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 435 FILESYSTEM__RELABELFROM, NULL); 436 if (rc) 437 return rc; 438 439 rc = avc_has_perm(&selinux_state, 440 sid, sbsec->sid, SECCLASS_FILESYSTEM, 441 FILESYSTEM__ASSOCIATE, NULL); 442 return rc; 443 } 444 445 static int selinux_is_genfs_special_handling(struct super_block *sb) 446 { 447 /* Special handling. Genfs but also in-core setxattr handler */ 448 return !strcmp(sb->s_type->name, "sysfs") || 449 !strcmp(sb->s_type->name, "pstore") || 450 !strcmp(sb->s_type->name, "debugfs") || 451 !strcmp(sb->s_type->name, "tracefs") || 452 !strcmp(sb->s_type->name, "rootfs") || 453 (selinux_policycap_cgroupseclabel() && 454 (!strcmp(sb->s_type->name, "cgroup") || 455 !strcmp(sb->s_type->name, "cgroup2"))); 456 } 457 458 static int selinux_is_sblabel_mnt(struct super_block *sb) 459 { 460 struct superblock_security_struct *sbsec = sb->s_security; 461 462 /* 463 * IMPORTANT: Double-check logic in this function when adding a new 464 * SECURITY_FS_USE_* definition! 465 */ 466 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 467 468 switch (sbsec->behavior) { 469 case SECURITY_FS_USE_XATTR: 470 case SECURITY_FS_USE_TRANS: 471 case SECURITY_FS_USE_TASK: 472 case SECURITY_FS_USE_NATIVE: 473 return 1; 474 475 case SECURITY_FS_USE_GENFS: 476 return selinux_is_genfs_special_handling(sb); 477 478 /* Never allow relabeling on context mounts */ 479 case SECURITY_FS_USE_MNTPOINT: 480 case SECURITY_FS_USE_NONE: 481 default: 482 return 0; 483 } 484 } 485 486 static int sb_finish_set_opts(struct super_block *sb) 487 { 488 struct superblock_security_struct *sbsec = sb->s_security; 489 struct dentry *root = sb->s_root; 490 struct inode *root_inode = d_backing_inode(root); 491 int rc = 0; 492 493 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 494 /* Make sure that the xattr handler exists and that no 495 error other than -ENODATA is returned by getxattr on 496 the root directory. -ENODATA is ok, as this may be 497 the first boot of the SELinux kernel before we have 498 assigned xattr values to the filesystem. */ 499 if (!(root_inode->i_opflags & IOP_XATTR)) { 500 pr_warn("SELinux: (dev %s, type %s) has no " 501 "xattr support\n", sb->s_id, sb->s_type->name); 502 rc = -EOPNOTSUPP; 503 goto out; 504 } 505 506 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 507 if (rc < 0 && rc != -ENODATA) { 508 if (rc == -EOPNOTSUPP) 509 pr_warn("SELinux: (dev %s, type " 510 "%s) has no security xattr handler\n", 511 sb->s_id, sb->s_type->name); 512 else 513 pr_warn("SELinux: (dev %s, type " 514 "%s) getxattr errno %d\n", sb->s_id, 515 sb->s_type->name, -rc); 516 goto out; 517 } 518 } 519 520 sbsec->flags |= SE_SBINITIALIZED; 521 522 /* 523 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 524 * leave the flag untouched because sb_clone_mnt_opts might be handing 525 * us a superblock that needs the flag to be cleared. 526 */ 527 if (selinux_is_sblabel_mnt(sb)) 528 sbsec->flags |= SBLABEL_MNT; 529 else 530 sbsec->flags &= ~SBLABEL_MNT; 531 532 /* Initialize the root inode. */ 533 rc = inode_doinit_with_dentry(root_inode, root); 534 535 /* Initialize any other inodes associated with the superblock, e.g. 536 inodes created prior to initial policy load or inodes created 537 during get_sb by a pseudo filesystem that directly 538 populates itself. */ 539 spin_lock(&sbsec->isec_lock); 540 while (!list_empty(&sbsec->isec_head)) { 541 struct inode_security_struct *isec = 542 list_first_entry(&sbsec->isec_head, 543 struct inode_security_struct, list); 544 struct inode *inode = isec->inode; 545 list_del_init(&isec->list); 546 spin_unlock(&sbsec->isec_lock); 547 inode = igrab(inode); 548 if (inode) { 549 if (!IS_PRIVATE(inode)) 550 inode_doinit_with_dentry(inode, NULL); 551 iput(inode); 552 } 553 spin_lock(&sbsec->isec_lock); 554 } 555 spin_unlock(&sbsec->isec_lock); 556 out: 557 return rc; 558 } 559 560 static int bad_option(struct superblock_security_struct *sbsec, char flag, 561 u32 old_sid, u32 new_sid) 562 { 563 char mnt_flags = sbsec->flags & SE_MNTMASK; 564 565 /* check if the old mount command had the same options */ 566 if (sbsec->flags & SE_SBINITIALIZED) 567 if (!(sbsec->flags & flag) || 568 (old_sid != new_sid)) 569 return 1; 570 571 /* check if we were passed the same options twice, 572 * aka someone passed context=a,context=b 573 */ 574 if (!(sbsec->flags & SE_SBINITIALIZED)) 575 if (mnt_flags & flag) 576 return 1; 577 return 0; 578 } 579 580 static int parse_sid(struct super_block *sb, const char *s, u32 *sid) 581 { 582 int rc = security_context_str_to_sid(&selinux_state, s, 583 sid, GFP_KERNEL); 584 if (rc) 585 pr_warn("SELinux: security_context_str_to_sid" 586 "(%s) failed for (dev %s, type %s) errno=%d\n", 587 s, sb->s_id, sb->s_type->name, rc); 588 return rc; 589 } 590 591 /* 592 * Allow filesystems with binary mount data to explicitly set mount point 593 * labeling information. 594 */ 595 static int selinux_set_mnt_opts(struct super_block *sb, 596 void *mnt_opts, 597 unsigned long kern_flags, 598 unsigned long *set_kern_flags) 599 { 600 const struct cred *cred = current_cred(); 601 struct superblock_security_struct *sbsec = sb->s_security; 602 struct dentry *root = sbsec->sb->s_root; 603 struct selinux_mnt_opts *opts = mnt_opts; 604 struct inode_security_struct *root_isec; 605 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 606 u32 defcontext_sid = 0; 607 int rc = 0; 608 609 mutex_lock(&sbsec->lock); 610 611 if (!selinux_initialized(&selinux_state)) { 612 if (!opts) { 613 /* Defer initialization until selinux_complete_init, 614 after the initial policy is loaded and the security 615 server is ready to handle calls. */ 616 goto out; 617 } 618 rc = -EINVAL; 619 pr_warn("SELinux: Unable to set superblock options " 620 "before the security server is initialized\n"); 621 goto out; 622 } 623 if (kern_flags && !set_kern_flags) { 624 /* Specifying internal flags without providing a place to 625 * place the results is not allowed */ 626 rc = -EINVAL; 627 goto out; 628 } 629 630 /* 631 * Binary mount data FS will come through this function twice. Once 632 * from an explicit call and once from the generic calls from the vfs. 633 * Since the generic VFS calls will not contain any security mount data 634 * we need to skip the double mount verification. 635 * 636 * This does open a hole in which we will not notice if the first 637 * mount using this sb set explict options and a second mount using 638 * this sb does not set any security options. (The first options 639 * will be used for both mounts) 640 */ 641 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 642 && !opts) 643 goto out; 644 645 root_isec = backing_inode_security_novalidate(root); 646 647 /* 648 * parse the mount options, check if they are valid sids. 649 * also check if someone is trying to mount the same sb more 650 * than once with different security options. 651 */ 652 if (opts) { 653 if (opts->fscontext) { 654 rc = parse_sid(sb, opts->fscontext, &fscontext_sid); 655 if (rc) 656 goto out; 657 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 658 fscontext_sid)) 659 goto out_double_mount; 660 sbsec->flags |= FSCONTEXT_MNT; 661 } 662 if (opts->context) { 663 rc = parse_sid(sb, opts->context, &context_sid); 664 if (rc) 665 goto out; 666 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 667 context_sid)) 668 goto out_double_mount; 669 sbsec->flags |= CONTEXT_MNT; 670 } 671 if (opts->rootcontext) { 672 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid); 673 if (rc) 674 goto out; 675 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 676 rootcontext_sid)) 677 goto out_double_mount; 678 sbsec->flags |= ROOTCONTEXT_MNT; 679 } 680 if (opts->defcontext) { 681 rc = parse_sid(sb, opts->defcontext, &defcontext_sid); 682 if (rc) 683 goto out; 684 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 685 defcontext_sid)) 686 goto out_double_mount; 687 sbsec->flags |= DEFCONTEXT_MNT; 688 } 689 } 690 691 if (sbsec->flags & SE_SBINITIALIZED) { 692 /* previously mounted with options, but not on this attempt? */ 693 if ((sbsec->flags & SE_MNTMASK) && !opts) 694 goto out_double_mount; 695 rc = 0; 696 goto out; 697 } 698 699 if (strcmp(sb->s_type->name, "proc") == 0) 700 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 701 702 if (!strcmp(sb->s_type->name, "debugfs") || 703 !strcmp(sb->s_type->name, "tracefs") || 704 !strcmp(sb->s_type->name, "binder") || 705 !strcmp(sb->s_type->name, "bpf") || 706 !strcmp(sb->s_type->name, "pstore")) 707 sbsec->flags |= SE_SBGENFS; 708 709 if (!strcmp(sb->s_type->name, "sysfs") || 710 !strcmp(sb->s_type->name, "cgroup") || 711 !strcmp(sb->s_type->name, "cgroup2")) 712 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 713 714 if (!sbsec->behavior) { 715 /* 716 * Determine the labeling behavior to use for this 717 * filesystem type. 718 */ 719 rc = security_fs_use(&selinux_state, sb); 720 if (rc) { 721 pr_warn("%s: security_fs_use(%s) returned %d\n", 722 __func__, sb->s_type->name, rc); 723 goto out; 724 } 725 } 726 727 /* 728 * If this is a user namespace mount and the filesystem type is not 729 * explicitly whitelisted, then no contexts are allowed on the command 730 * line and security labels must be ignored. 731 */ 732 if (sb->s_user_ns != &init_user_ns && 733 strcmp(sb->s_type->name, "tmpfs") && 734 strcmp(sb->s_type->name, "ramfs") && 735 strcmp(sb->s_type->name, "devpts")) { 736 if (context_sid || fscontext_sid || rootcontext_sid || 737 defcontext_sid) { 738 rc = -EACCES; 739 goto out; 740 } 741 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 742 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 743 rc = security_transition_sid(&selinux_state, 744 current_sid(), 745 current_sid(), 746 SECCLASS_FILE, NULL, 747 &sbsec->mntpoint_sid); 748 if (rc) 749 goto out; 750 } 751 goto out_set_opts; 752 } 753 754 /* sets the context of the superblock for the fs being mounted. */ 755 if (fscontext_sid) { 756 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 757 if (rc) 758 goto out; 759 760 sbsec->sid = fscontext_sid; 761 } 762 763 /* 764 * Switch to using mount point labeling behavior. 765 * sets the label used on all file below the mountpoint, and will set 766 * the superblock context if not already set. 767 */ 768 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 769 sbsec->behavior = SECURITY_FS_USE_NATIVE; 770 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 771 } 772 773 if (context_sid) { 774 if (!fscontext_sid) { 775 rc = may_context_mount_sb_relabel(context_sid, sbsec, 776 cred); 777 if (rc) 778 goto out; 779 sbsec->sid = context_sid; 780 } else { 781 rc = may_context_mount_inode_relabel(context_sid, sbsec, 782 cred); 783 if (rc) 784 goto out; 785 } 786 if (!rootcontext_sid) 787 rootcontext_sid = context_sid; 788 789 sbsec->mntpoint_sid = context_sid; 790 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 791 } 792 793 if (rootcontext_sid) { 794 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 795 cred); 796 if (rc) 797 goto out; 798 799 root_isec->sid = rootcontext_sid; 800 root_isec->initialized = LABEL_INITIALIZED; 801 } 802 803 if (defcontext_sid) { 804 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 805 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 806 rc = -EINVAL; 807 pr_warn("SELinux: defcontext option is " 808 "invalid for this filesystem type\n"); 809 goto out; 810 } 811 812 if (defcontext_sid != sbsec->def_sid) { 813 rc = may_context_mount_inode_relabel(defcontext_sid, 814 sbsec, cred); 815 if (rc) 816 goto out; 817 } 818 819 sbsec->def_sid = defcontext_sid; 820 } 821 822 out_set_opts: 823 rc = sb_finish_set_opts(sb); 824 out: 825 mutex_unlock(&sbsec->lock); 826 return rc; 827 out_double_mount: 828 rc = -EINVAL; 829 pr_warn("SELinux: mount invalid. Same superblock, different " 830 "security settings for (dev %s, type %s)\n", sb->s_id, 831 sb->s_type->name); 832 goto out; 833 } 834 835 static int selinux_cmp_sb_context(const struct super_block *oldsb, 836 const struct super_block *newsb) 837 { 838 struct superblock_security_struct *old = oldsb->s_security; 839 struct superblock_security_struct *new = newsb->s_security; 840 char oldflags = old->flags & SE_MNTMASK; 841 char newflags = new->flags & SE_MNTMASK; 842 843 if (oldflags != newflags) 844 goto mismatch; 845 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 846 goto mismatch; 847 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 848 goto mismatch; 849 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 850 goto mismatch; 851 if (oldflags & ROOTCONTEXT_MNT) { 852 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 853 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 854 if (oldroot->sid != newroot->sid) 855 goto mismatch; 856 } 857 return 0; 858 mismatch: 859 pr_warn("SELinux: mount invalid. Same superblock, " 860 "different security settings for (dev %s, " 861 "type %s)\n", newsb->s_id, newsb->s_type->name); 862 return -EBUSY; 863 } 864 865 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 866 struct super_block *newsb, 867 unsigned long kern_flags, 868 unsigned long *set_kern_flags) 869 { 870 int rc = 0; 871 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 872 struct superblock_security_struct *newsbsec = newsb->s_security; 873 874 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 875 int set_context = (oldsbsec->flags & CONTEXT_MNT); 876 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 877 878 /* 879 * if the parent was able to be mounted it clearly had no special lsm 880 * mount options. thus we can safely deal with this superblock later 881 */ 882 if (!selinux_initialized(&selinux_state)) 883 return 0; 884 885 /* 886 * Specifying internal flags without providing a place to 887 * place the results is not allowed. 888 */ 889 if (kern_flags && !set_kern_flags) 890 return -EINVAL; 891 892 /* how can we clone if the old one wasn't set up?? */ 893 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 894 895 /* if fs is reusing a sb, make sure that the contexts match */ 896 if (newsbsec->flags & SE_SBINITIALIZED) { 897 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 898 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 899 return selinux_cmp_sb_context(oldsb, newsb); 900 } 901 902 mutex_lock(&newsbsec->lock); 903 904 newsbsec->flags = oldsbsec->flags; 905 906 newsbsec->sid = oldsbsec->sid; 907 newsbsec->def_sid = oldsbsec->def_sid; 908 newsbsec->behavior = oldsbsec->behavior; 909 910 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 911 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 912 rc = security_fs_use(&selinux_state, newsb); 913 if (rc) 914 goto out; 915 } 916 917 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 918 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 919 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 920 } 921 922 if (set_context) { 923 u32 sid = oldsbsec->mntpoint_sid; 924 925 if (!set_fscontext) 926 newsbsec->sid = sid; 927 if (!set_rootcontext) { 928 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 929 newisec->sid = sid; 930 } 931 newsbsec->mntpoint_sid = sid; 932 } 933 if (set_rootcontext) { 934 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 935 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 936 937 newisec->sid = oldisec->sid; 938 } 939 940 sb_finish_set_opts(newsb); 941 out: 942 mutex_unlock(&newsbsec->lock); 943 return rc; 944 } 945 946 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 947 { 948 struct selinux_mnt_opts *opts = *mnt_opts; 949 950 if (token == Opt_seclabel) /* eaten and completely ignored */ 951 return 0; 952 953 if (!opts) { 954 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 955 if (!opts) 956 return -ENOMEM; 957 *mnt_opts = opts; 958 } 959 if (!s) 960 return -ENOMEM; 961 switch (token) { 962 case Opt_context: 963 if (opts->context || opts->defcontext) 964 goto Einval; 965 opts->context = s; 966 break; 967 case Opt_fscontext: 968 if (opts->fscontext) 969 goto Einval; 970 opts->fscontext = s; 971 break; 972 case Opt_rootcontext: 973 if (opts->rootcontext) 974 goto Einval; 975 opts->rootcontext = s; 976 break; 977 case Opt_defcontext: 978 if (opts->context || opts->defcontext) 979 goto Einval; 980 opts->defcontext = s; 981 break; 982 } 983 return 0; 984 Einval: 985 pr_warn(SEL_MOUNT_FAIL_MSG); 986 return -EINVAL; 987 } 988 989 static int selinux_add_mnt_opt(const char *option, const char *val, int len, 990 void **mnt_opts) 991 { 992 int token = Opt_error; 993 int rc, i; 994 995 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 996 if (strcmp(option, tokens[i].name) == 0) { 997 token = tokens[i].opt; 998 break; 999 } 1000 } 1001 1002 if (token == Opt_error) 1003 return -EINVAL; 1004 1005 if (token != Opt_seclabel) { 1006 val = kmemdup_nul(val, len, GFP_KERNEL); 1007 if (!val) { 1008 rc = -ENOMEM; 1009 goto free_opt; 1010 } 1011 } 1012 rc = selinux_add_opt(token, val, mnt_opts); 1013 if (unlikely(rc)) { 1014 kfree(val); 1015 goto free_opt; 1016 } 1017 return rc; 1018 1019 free_opt: 1020 if (*mnt_opts) { 1021 selinux_free_mnt_opts(*mnt_opts); 1022 *mnt_opts = NULL; 1023 } 1024 return rc; 1025 } 1026 1027 static int show_sid(struct seq_file *m, u32 sid) 1028 { 1029 char *context = NULL; 1030 u32 len; 1031 int rc; 1032 1033 rc = security_sid_to_context(&selinux_state, sid, 1034 &context, &len); 1035 if (!rc) { 1036 bool has_comma = context && strchr(context, ','); 1037 1038 seq_putc(m, '='); 1039 if (has_comma) 1040 seq_putc(m, '\"'); 1041 seq_escape(m, context, "\"\n\\"); 1042 if (has_comma) 1043 seq_putc(m, '\"'); 1044 } 1045 kfree(context); 1046 return rc; 1047 } 1048 1049 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1050 { 1051 struct superblock_security_struct *sbsec = sb->s_security; 1052 int rc; 1053 1054 if (!(sbsec->flags & SE_SBINITIALIZED)) 1055 return 0; 1056 1057 if (!selinux_initialized(&selinux_state)) 1058 return 0; 1059 1060 if (sbsec->flags & FSCONTEXT_MNT) { 1061 seq_putc(m, ','); 1062 seq_puts(m, FSCONTEXT_STR); 1063 rc = show_sid(m, sbsec->sid); 1064 if (rc) 1065 return rc; 1066 } 1067 if (sbsec->flags & CONTEXT_MNT) { 1068 seq_putc(m, ','); 1069 seq_puts(m, CONTEXT_STR); 1070 rc = show_sid(m, sbsec->mntpoint_sid); 1071 if (rc) 1072 return rc; 1073 } 1074 if (sbsec->flags & DEFCONTEXT_MNT) { 1075 seq_putc(m, ','); 1076 seq_puts(m, DEFCONTEXT_STR); 1077 rc = show_sid(m, sbsec->def_sid); 1078 if (rc) 1079 return rc; 1080 } 1081 if (sbsec->flags & ROOTCONTEXT_MNT) { 1082 struct dentry *root = sbsec->sb->s_root; 1083 struct inode_security_struct *isec = backing_inode_security(root); 1084 seq_putc(m, ','); 1085 seq_puts(m, ROOTCONTEXT_STR); 1086 rc = show_sid(m, isec->sid); 1087 if (rc) 1088 return rc; 1089 } 1090 if (sbsec->flags & SBLABEL_MNT) { 1091 seq_putc(m, ','); 1092 seq_puts(m, SECLABEL_STR); 1093 } 1094 return 0; 1095 } 1096 1097 static inline u16 inode_mode_to_security_class(umode_t mode) 1098 { 1099 switch (mode & S_IFMT) { 1100 case S_IFSOCK: 1101 return SECCLASS_SOCK_FILE; 1102 case S_IFLNK: 1103 return SECCLASS_LNK_FILE; 1104 case S_IFREG: 1105 return SECCLASS_FILE; 1106 case S_IFBLK: 1107 return SECCLASS_BLK_FILE; 1108 case S_IFDIR: 1109 return SECCLASS_DIR; 1110 case S_IFCHR: 1111 return SECCLASS_CHR_FILE; 1112 case S_IFIFO: 1113 return SECCLASS_FIFO_FILE; 1114 1115 } 1116 1117 return SECCLASS_FILE; 1118 } 1119 1120 static inline int default_protocol_stream(int protocol) 1121 { 1122 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1123 } 1124 1125 static inline int default_protocol_dgram(int protocol) 1126 { 1127 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1128 } 1129 1130 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1131 { 1132 int extsockclass = selinux_policycap_extsockclass(); 1133 1134 switch (family) { 1135 case PF_UNIX: 1136 switch (type) { 1137 case SOCK_STREAM: 1138 case SOCK_SEQPACKET: 1139 return SECCLASS_UNIX_STREAM_SOCKET; 1140 case SOCK_DGRAM: 1141 case SOCK_RAW: 1142 return SECCLASS_UNIX_DGRAM_SOCKET; 1143 } 1144 break; 1145 case PF_INET: 1146 case PF_INET6: 1147 switch (type) { 1148 case SOCK_STREAM: 1149 case SOCK_SEQPACKET: 1150 if (default_protocol_stream(protocol)) 1151 return SECCLASS_TCP_SOCKET; 1152 else if (extsockclass && protocol == IPPROTO_SCTP) 1153 return SECCLASS_SCTP_SOCKET; 1154 else 1155 return SECCLASS_RAWIP_SOCKET; 1156 case SOCK_DGRAM: 1157 if (default_protocol_dgram(protocol)) 1158 return SECCLASS_UDP_SOCKET; 1159 else if (extsockclass && (protocol == IPPROTO_ICMP || 1160 protocol == IPPROTO_ICMPV6)) 1161 return SECCLASS_ICMP_SOCKET; 1162 else 1163 return SECCLASS_RAWIP_SOCKET; 1164 case SOCK_DCCP: 1165 return SECCLASS_DCCP_SOCKET; 1166 default: 1167 return SECCLASS_RAWIP_SOCKET; 1168 } 1169 break; 1170 case PF_NETLINK: 1171 switch (protocol) { 1172 case NETLINK_ROUTE: 1173 return SECCLASS_NETLINK_ROUTE_SOCKET; 1174 case NETLINK_SOCK_DIAG: 1175 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1176 case NETLINK_NFLOG: 1177 return SECCLASS_NETLINK_NFLOG_SOCKET; 1178 case NETLINK_XFRM: 1179 return SECCLASS_NETLINK_XFRM_SOCKET; 1180 case NETLINK_SELINUX: 1181 return SECCLASS_NETLINK_SELINUX_SOCKET; 1182 case NETLINK_ISCSI: 1183 return SECCLASS_NETLINK_ISCSI_SOCKET; 1184 case NETLINK_AUDIT: 1185 return SECCLASS_NETLINK_AUDIT_SOCKET; 1186 case NETLINK_FIB_LOOKUP: 1187 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1188 case NETLINK_CONNECTOR: 1189 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1190 case NETLINK_NETFILTER: 1191 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1192 case NETLINK_DNRTMSG: 1193 return SECCLASS_NETLINK_DNRT_SOCKET; 1194 case NETLINK_KOBJECT_UEVENT: 1195 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1196 case NETLINK_GENERIC: 1197 return SECCLASS_NETLINK_GENERIC_SOCKET; 1198 case NETLINK_SCSITRANSPORT: 1199 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1200 case NETLINK_RDMA: 1201 return SECCLASS_NETLINK_RDMA_SOCKET; 1202 case NETLINK_CRYPTO: 1203 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1204 default: 1205 return SECCLASS_NETLINK_SOCKET; 1206 } 1207 case PF_PACKET: 1208 return SECCLASS_PACKET_SOCKET; 1209 case PF_KEY: 1210 return SECCLASS_KEY_SOCKET; 1211 case PF_APPLETALK: 1212 return SECCLASS_APPLETALK_SOCKET; 1213 } 1214 1215 if (extsockclass) { 1216 switch (family) { 1217 case PF_AX25: 1218 return SECCLASS_AX25_SOCKET; 1219 case PF_IPX: 1220 return SECCLASS_IPX_SOCKET; 1221 case PF_NETROM: 1222 return SECCLASS_NETROM_SOCKET; 1223 case PF_ATMPVC: 1224 return SECCLASS_ATMPVC_SOCKET; 1225 case PF_X25: 1226 return SECCLASS_X25_SOCKET; 1227 case PF_ROSE: 1228 return SECCLASS_ROSE_SOCKET; 1229 case PF_DECnet: 1230 return SECCLASS_DECNET_SOCKET; 1231 case PF_ATMSVC: 1232 return SECCLASS_ATMSVC_SOCKET; 1233 case PF_RDS: 1234 return SECCLASS_RDS_SOCKET; 1235 case PF_IRDA: 1236 return SECCLASS_IRDA_SOCKET; 1237 case PF_PPPOX: 1238 return SECCLASS_PPPOX_SOCKET; 1239 case PF_LLC: 1240 return SECCLASS_LLC_SOCKET; 1241 case PF_CAN: 1242 return SECCLASS_CAN_SOCKET; 1243 case PF_TIPC: 1244 return SECCLASS_TIPC_SOCKET; 1245 case PF_BLUETOOTH: 1246 return SECCLASS_BLUETOOTH_SOCKET; 1247 case PF_IUCV: 1248 return SECCLASS_IUCV_SOCKET; 1249 case PF_RXRPC: 1250 return SECCLASS_RXRPC_SOCKET; 1251 case PF_ISDN: 1252 return SECCLASS_ISDN_SOCKET; 1253 case PF_PHONET: 1254 return SECCLASS_PHONET_SOCKET; 1255 case PF_IEEE802154: 1256 return SECCLASS_IEEE802154_SOCKET; 1257 case PF_CAIF: 1258 return SECCLASS_CAIF_SOCKET; 1259 case PF_ALG: 1260 return SECCLASS_ALG_SOCKET; 1261 case PF_NFC: 1262 return SECCLASS_NFC_SOCKET; 1263 case PF_VSOCK: 1264 return SECCLASS_VSOCK_SOCKET; 1265 case PF_KCM: 1266 return SECCLASS_KCM_SOCKET; 1267 case PF_QIPCRTR: 1268 return SECCLASS_QIPCRTR_SOCKET; 1269 case PF_SMC: 1270 return SECCLASS_SMC_SOCKET; 1271 case PF_XDP: 1272 return SECCLASS_XDP_SOCKET; 1273 #if PF_MAX > 45 1274 #error New address family defined, please update this function. 1275 #endif 1276 } 1277 } 1278 1279 return SECCLASS_SOCKET; 1280 } 1281 1282 static int selinux_genfs_get_sid(struct dentry *dentry, 1283 u16 tclass, 1284 u16 flags, 1285 u32 *sid) 1286 { 1287 int rc; 1288 struct super_block *sb = dentry->d_sb; 1289 char *buffer, *path; 1290 1291 buffer = (char *)__get_free_page(GFP_KERNEL); 1292 if (!buffer) 1293 return -ENOMEM; 1294 1295 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1296 if (IS_ERR(path)) 1297 rc = PTR_ERR(path); 1298 else { 1299 if (flags & SE_SBPROC) { 1300 /* each process gets a /proc/PID/ entry. Strip off the 1301 * PID part to get a valid selinux labeling. 1302 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1303 while (path[1] >= '0' && path[1] <= '9') { 1304 path[1] = '/'; 1305 path++; 1306 } 1307 } 1308 rc = security_genfs_sid(&selinux_state, sb->s_type->name, 1309 path, tclass, sid); 1310 if (rc == -ENOENT) { 1311 /* No match in policy, mark as unlabeled. */ 1312 *sid = SECINITSID_UNLABELED; 1313 rc = 0; 1314 } 1315 } 1316 free_page((unsigned long)buffer); 1317 return rc; 1318 } 1319 1320 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1321 u32 def_sid, u32 *sid) 1322 { 1323 #define INITCONTEXTLEN 255 1324 char *context; 1325 unsigned int len; 1326 int rc; 1327 1328 len = INITCONTEXTLEN; 1329 context = kmalloc(len + 1, GFP_NOFS); 1330 if (!context) 1331 return -ENOMEM; 1332 1333 context[len] = '\0'; 1334 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1335 if (rc == -ERANGE) { 1336 kfree(context); 1337 1338 /* Need a larger buffer. Query for the right size. */ 1339 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1340 if (rc < 0) 1341 return rc; 1342 1343 len = rc; 1344 context = kmalloc(len + 1, GFP_NOFS); 1345 if (!context) 1346 return -ENOMEM; 1347 1348 context[len] = '\0'; 1349 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1350 context, len); 1351 } 1352 if (rc < 0) { 1353 kfree(context); 1354 if (rc != -ENODATA) { 1355 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1356 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1357 return rc; 1358 } 1359 *sid = def_sid; 1360 return 0; 1361 } 1362 1363 rc = security_context_to_sid_default(&selinux_state, context, rc, sid, 1364 def_sid, GFP_NOFS); 1365 if (rc) { 1366 char *dev = inode->i_sb->s_id; 1367 unsigned long ino = inode->i_ino; 1368 1369 if (rc == -EINVAL) { 1370 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", 1371 ino, dev, context); 1372 } else { 1373 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1374 __func__, context, -rc, dev, ino); 1375 } 1376 } 1377 kfree(context); 1378 return 0; 1379 } 1380 1381 /* The inode's security attributes must be initialized before first use. */ 1382 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1383 { 1384 struct superblock_security_struct *sbsec = NULL; 1385 struct inode_security_struct *isec = selinux_inode(inode); 1386 u32 task_sid, sid = 0; 1387 u16 sclass; 1388 struct dentry *dentry; 1389 int rc = 0; 1390 1391 if (isec->initialized == LABEL_INITIALIZED) 1392 return 0; 1393 1394 spin_lock(&isec->lock); 1395 if (isec->initialized == LABEL_INITIALIZED) 1396 goto out_unlock; 1397 1398 if (isec->sclass == SECCLASS_FILE) 1399 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1400 1401 sbsec = inode->i_sb->s_security; 1402 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1403 /* Defer initialization until selinux_complete_init, 1404 after the initial policy is loaded and the security 1405 server is ready to handle calls. */ 1406 spin_lock(&sbsec->isec_lock); 1407 if (list_empty(&isec->list)) 1408 list_add(&isec->list, &sbsec->isec_head); 1409 spin_unlock(&sbsec->isec_lock); 1410 goto out_unlock; 1411 } 1412 1413 sclass = isec->sclass; 1414 task_sid = isec->task_sid; 1415 sid = isec->sid; 1416 isec->initialized = LABEL_PENDING; 1417 spin_unlock(&isec->lock); 1418 1419 switch (sbsec->behavior) { 1420 case SECURITY_FS_USE_NATIVE: 1421 break; 1422 case SECURITY_FS_USE_XATTR: 1423 if (!(inode->i_opflags & IOP_XATTR)) { 1424 sid = sbsec->def_sid; 1425 break; 1426 } 1427 /* Need a dentry, since the xattr API requires one. 1428 Life would be simpler if we could just pass the inode. */ 1429 if (opt_dentry) { 1430 /* Called from d_instantiate or d_splice_alias. */ 1431 dentry = dget(opt_dentry); 1432 } else { 1433 /* 1434 * Called from selinux_complete_init, try to find a dentry. 1435 * Some filesystems really want a connected one, so try 1436 * that first. We could split SECURITY_FS_USE_XATTR in 1437 * two, depending upon that... 1438 */ 1439 dentry = d_find_alias(inode); 1440 if (!dentry) 1441 dentry = d_find_any_alias(inode); 1442 } 1443 if (!dentry) { 1444 /* 1445 * this is can be hit on boot when a file is accessed 1446 * before the policy is loaded. When we load policy we 1447 * may find inodes that have no dentry on the 1448 * sbsec->isec_head list. No reason to complain as these 1449 * will get fixed up the next time we go through 1450 * inode_doinit with a dentry, before these inodes could 1451 * be used again by userspace. 1452 */ 1453 goto out; 1454 } 1455 1456 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1457 &sid); 1458 dput(dentry); 1459 if (rc) 1460 goto out; 1461 break; 1462 case SECURITY_FS_USE_TASK: 1463 sid = task_sid; 1464 break; 1465 case SECURITY_FS_USE_TRANS: 1466 /* Default to the fs SID. */ 1467 sid = sbsec->sid; 1468 1469 /* Try to obtain a transition SID. */ 1470 rc = security_transition_sid(&selinux_state, task_sid, sid, 1471 sclass, NULL, &sid); 1472 if (rc) 1473 goto out; 1474 break; 1475 case SECURITY_FS_USE_MNTPOINT: 1476 sid = sbsec->mntpoint_sid; 1477 break; 1478 default: 1479 /* Default to the fs superblock SID. */ 1480 sid = sbsec->sid; 1481 1482 if ((sbsec->flags & SE_SBGENFS) && 1483 (!S_ISLNK(inode->i_mode) || 1484 selinux_policycap_genfs_seclabel_symlinks())) { 1485 /* We must have a dentry to determine the label on 1486 * procfs inodes */ 1487 if (opt_dentry) { 1488 /* Called from d_instantiate or 1489 * d_splice_alias. */ 1490 dentry = dget(opt_dentry); 1491 } else { 1492 /* Called from selinux_complete_init, try to 1493 * find a dentry. Some filesystems really want 1494 * a connected one, so try that first. 1495 */ 1496 dentry = d_find_alias(inode); 1497 if (!dentry) 1498 dentry = d_find_any_alias(inode); 1499 } 1500 /* 1501 * This can be hit on boot when a file is accessed 1502 * before the policy is loaded. When we load policy we 1503 * may find inodes that have no dentry on the 1504 * sbsec->isec_head list. No reason to complain as 1505 * these will get fixed up the next time we go through 1506 * inode_doinit() with a dentry, before these inodes 1507 * could be used again by userspace. 1508 */ 1509 if (!dentry) 1510 goto out; 1511 rc = selinux_genfs_get_sid(dentry, sclass, 1512 sbsec->flags, &sid); 1513 if (rc) { 1514 dput(dentry); 1515 goto out; 1516 } 1517 1518 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1519 (inode->i_opflags & IOP_XATTR)) { 1520 rc = inode_doinit_use_xattr(inode, dentry, 1521 sid, &sid); 1522 if (rc) { 1523 dput(dentry); 1524 goto out; 1525 } 1526 } 1527 dput(dentry); 1528 } 1529 break; 1530 } 1531 1532 out: 1533 spin_lock(&isec->lock); 1534 if (isec->initialized == LABEL_PENDING) { 1535 if (!sid || rc) { 1536 isec->initialized = LABEL_INVALID; 1537 goto out_unlock; 1538 } 1539 1540 isec->initialized = LABEL_INITIALIZED; 1541 isec->sid = sid; 1542 } 1543 1544 out_unlock: 1545 spin_unlock(&isec->lock); 1546 return rc; 1547 } 1548 1549 /* Convert a Linux signal to an access vector. */ 1550 static inline u32 signal_to_av(int sig) 1551 { 1552 u32 perm = 0; 1553 1554 switch (sig) { 1555 case SIGCHLD: 1556 /* Commonly granted from child to parent. */ 1557 perm = PROCESS__SIGCHLD; 1558 break; 1559 case SIGKILL: 1560 /* Cannot be caught or ignored */ 1561 perm = PROCESS__SIGKILL; 1562 break; 1563 case SIGSTOP: 1564 /* Cannot be caught or ignored */ 1565 perm = PROCESS__SIGSTOP; 1566 break; 1567 default: 1568 /* All other signals. */ 1569 perm = PROCESS__SIGNAL; 1570 break; 1571 } 1572 1573 return perm; 1574 } 1575 1576 #if CAP_LAST_CAP > 63 1577 #error Fix SELinux to handle capabilities > 63. 1578 #endif 1579 1580 /* Check whether a task is allowed to use a capability. */ 1581 static int cred_has_capability(const struct cred *cred, 1582 int cap, unsigned int opts, bool initns) 1583 { 1584 struct common_audit_data ad; 1585 struct av_decision avd; 1586 u16 sclass; 1587 u32 sid = cred_sid(cred); 1588 u32 av = CAP_TO_MASK(cap); 1589 int rc; 1590 1591 ad.type = LSM_AUDIT_DATA_CAP; 1592 ad.u.cap = cap; 1593 1594 switch (CAP_TO_INDEX(cap)) { 1595 case 0: 1596 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1597 break; 1598 case 1: 1599 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1600 break; 1601 default: 1602 pr_err("SELinux: out of range capability %d\n", cap); 1603 BUG(); 1604 return -EINVAL; 1605 } 1606 1607 rc = avc_has_perm_noaudit(&selinux_state, 1608 sid, sid, sclass, av, 0, &avd); 1609 if (!(opts & CAP_OPT_NOAUDIT)) { 1610 int rc2 = avc_audit(&selinux_state, 1611 sid, sid, sclass, av, &avd, rc, &ad, 0); 1612 if (rc2) 1613 return rc2; 1614 } 1615 return rc; 1616 } 1617 1618 /* Check whether a task has a particular permission to an inode. 1619 The 'adp' parameter is optional and allows other audit 1620 data to be passed (e.g. the dentry). */ 1621 static int inode_has_perm(const struct cred *cred, 1622 struct inode *inode, 1623 u32 perms, 1624 struct common_audit_data *adp) 1625 { 1626 struct inode_security_struct *isec; 1627 u32 sid; 1628 1629 validate_creds(cred); 1630 1631 if (unlikely(IS_PRIVATE(inode))) 1632 return 0; 1633 1634 sid = cred_sid(cred); 1635 isec = selinux_inode(inode); 1636 1637 return avc_has_perm(&selinux_state, 1638 sid, isec->sid, isec->sclass, perms, adp); 1639 } 1640 1641 /* Same as inode_has_perm, but pass explicit audit data containing 1642 the dentry to help the auditing code to more easily generate the 1643 pathname if needed. */ 1644 static inline int dentry_has_perm(const struct cred *cred, 1645 struct dentry *dentry, 1646 u32 av) 1647 { 1648 struct inode *inode = d_backing_inode(dentry); 1649 struct common_audit_data ad; 1650 1651 ad.type = LSM_AUDIT_DATA_DENTRY; 1652 ad.u.dentry = dentry; 1653 __inode_security_revalidate(inode, dentry, true); 1654 return inode_has_perm(cred, inode, av, &ad); 1655 } 1656 1657 /* Same as inode_has_perm, but pass explicit audit data containing 1658 the path to help the auditing code to more easily generate the 1659 pathname if needed. */ 1660 static inline int path_has_perm(const struct cred *cred, 1661 const struct path *path, 1662 u32 av) 1663 { 1664 struct inode *inode = d_backing_inode(path->dentry); 1665 struct common_audit_data ad; 1666 1667 ad.type = LSM_AUDIT_DATA_PATH; 1668 ad.u.path = *path; 1669 __inode_security_revalidate(inode, path->dentry, true); 1670 return inode_has_perm(cred, inode, av, &ad); 1671 } 1672 1673 /* Same as path_has_perm, but uses the inode from the file struct. */ 1674 static inline int file_path_has_perm(const struct cred *cred, 1675 struct file *file, 1676 u32 av) 1677 { 1678 struct common_audit_data ad; 1679 1680 ad.type = LSM_AUDIT_DATA_FILE; 1681 ad.u.file = file; 1682 return inode_has_perm(cred, file_inode(file), av, &ad); 1683 } 1684 1685 #ifdef CONFIG_BPF_SYSCALL 1686 static int bpf_fd_pass(struct file *file, u32 sid); 1687 #endif 1688 1689 /* Check whether a task can use an open file descriptor to 1690 access an inode in a given way. Check access to the 1691 descriptor itself, and then use dentry_has_perm to 1692 check a particular permission to the file. 1693 Access to the descriptor is implicitly granted if it 1694 has the same SID as the process. If av is zero, then 1695 access to the file is not checked, e.g. for cases 1696 where only the descriptor is affected like seek. */ 1697 static int file_has_perm(const struct cred *cred, 1698 struct file *file, 1699 u32 av) 1700 { 1701 struct file_security_struct *fsec = selinux_file(file); 1702 struct inode *inode = file_inode(file); 1703 struct common_audit_data ad; 1704 u32 sid = cred_sid(cred); 1705 int rc; 1706 1707 ad.type = LSM_AUDIT_DATA_FILE; 1708 ad.u.file = file; 1709 1710 if (sid != fsec->sid) { 1711 rc = avc_has_perm(&selinux_state, 1712 sid, fsec->sid, 1713 SECCLASS_FD, 1714 FD__USE, 1715 &ad); 1716 if (rc) 1717 goto out; 1718 } 1719 1720 #ifdef CONFIG_BPF_SYSCALL 1721 rc = bpf_fd_pass(file, cred_sid(cred)); 1722 if (rc) 1723 return rc; 1724 #endif 1725 1726 /* av is zero if only checking access to the descriptor. */ 1727 rc = 0; 1728 if (av) 1729 rc = inode_has_perm(cred, inode, av, &ad); 1730 1731 out: 1732 return rc; 1733 } 1734 1735 /* 1736 * Determine the label for an inode that might be unioned. 1737 */ 1738 static int 1739 selinux_determine_inode_label(const struct task_security_struct *tsec, 1740 struct inode *dir, 1741 const struct qstr *name, u16 tclass, 1742 u32 *_new_isid) 1743 { 1744 const struct superblock_security_struct *sbsec = dir->i_sb->s_security; 1745 1746 if ((sbsec->flags & SE_SBINITIALIZED) && 1747 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1748 *_new_isid = sbsec->mntpoint_sid; 1749 } else if ((sbsec->flags & SBLABEL_MNT) && 1750 tsec->create_sid) { 1751 *_new_isid = tsec->create_sid; 1752 } else { 1753 const struct inode_security_struct *dsec = inode_security(dir); 1754 return security_transition_sid(&selinux_state, tsec->sid, 1755 dsec->sid, tclass, 1756 name, _new_isid); 1757 } 1758 1759 return 0; 1760 } 1761 1762 /* Check whether a task can create a file. */ 1763 static int may_create(struct inode *dir, 1764 struct dentry *dentry, 1765 u16 tclass) 1766 { 1767 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1768 struct inode_security_struct *dsec; 1769 struct superblock_security_struct *sbsec; 1770 u32 sid, newsid; 1771 struct common_audit_data ad; 1772 int rc; 1773 1774 dsec = inode_security(dir); 1775 sbsec = dir->i_sb->s_security; 1776 1777 sid = tsec->sid; 1778 1779 ad.type = LSM_AUDIT_DATA_DENTRY; 1780 ad.u.dentry = dentry; 1781 1782 rc = avc_has_perm(&selinux_state, 1783 sid, dsec->sid, SECCLASS_DIR, 1784 DIR__ADD_NAME | DIR__SEARCH, 1785 &ad); 1786 if (rc) 1787 return rc; 1788 1789 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1790 &newsid); 1791 if (rc) 1792 return rc; 1793 1794 rc = avc_has_perm(&selinux_state, 1795 sid, newsid, tclass, FILE__CREATE, &ad); 1796 if (rc) 1797 return rc; 1798 1799 return avc_has_perm(&selinux_state, 1800 newsid, sbsec->sid, 1801 SECCLASS_FILESYSTEM, 1802 FILESYSTEM__ASSOCIATE, &ad); 1803 } 1804 1805 #define MAY_LINK 0 1806 #define MAY_UNLINK 1 1807 #define MAY_RMDIR 2 1808 1809 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1810 static int may_link(struct inode *dir, 1811 struct dentry *dentry, 1812 int kind) 1813 1814 { 1815 struct inode_security_struct *dsec, *isec; 1816 struct common_audit_data ad; 1817 u32 sid = current_sid(); 1818 u32 av; 1819 int rc; 1820 1821 dsec = inode_security(dir); 1822 isec = backing_inode_security(dentry); 1823 1824 ad.type = LSM_AUDIT_DATA_DENTRY; 1825 ad.u.dentry = dentry; 1826 1827 av = DIR__SEARCH; 1828 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1829 rc = avc_has_perm(&selinux_state, 1830 sid, dsec->sid, SECCLASS_DIR, av, &ad); 1831 if (rc) 1832 return rc; 1833 1834 switch (kind) { 1835 case MAY_LINK: 1836 av = FILE__LINK; 1837 break; 1838 case MAY_UNLINK: 1839 av = FILE__UNLINK; 1840 break; 1841 case MAY_RMDIR: 1842 av = DIR__RMDIR; 1843 break; 1844 default: 1845 pr_warn("SELinux: %s: unrecognized kind %d\n", 1846 __func__, kind); 1847 return 0; 1848 } 1849 1850 rc = avc_has_perm(&selinux_state, 1851 sid, isec->sid, isec->sclass, av, &ad); 1852 return rc; 1853 } 1854 1855 static inline int may_rename(struct inode *old_dir, 1856 struct dentry *old_dentry, 1857 struct inode *new_dir, 1858 struct dentry *new_dentry) 1859 { 1860 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1861 struct common_audit_data ad; 1862 u32 sid = current_sid(); 1863 u32 av; 1864 int old_is_dir, new_is_dir; 1865 int rc; 1866 1867 old_dsec = inode_security(old_dir); 1868 old_isec = backing_inode_security(old_dentry); 1869 old_is_dir = d_is_dir(old_dentry); 1870 new_dsec = inode_security(new_dir); 1871 1872 ad.type = LSM_AUDIT_DATA_DENTRY; 1873 1874 ad.u.dentry = old_dentry; 1875 rc = avc_has_perm(&selinux_state, 1876 sid, old_dsec->sid, SECCLASS_DIR, 1877 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1878 if (rc) 1879 return rc; 1880 rc = avc_has_perm(&selinux_state, 1881 sid, old_isec->sid, 1882 old_isec->sclass, FILE__RENAME, &ad); 1883 if (rc) 1884 return rc; 1885 if (old_is_dir && new_dir != old_dir) { 1886 rc = avc_has_perm(&selinux_state, 1887 sid, old_isec->sid, 1888 old_isec->sclass, DIR__REPARENT, &ad); 1889 if (rc) 1890 return rc; 1891 } 1892 1893 ad.u.dentry = new_dentry; 1894 av = DIR__ADD_NAME | DIR__SEARCH; 1895 if (d_is_positive(new_dentry)) 1896 av |= DIR__REMOVE_NAME; 1897 rc = avc_has_perm(&selinux_state, 1898 sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1899 if (rc) 1900 return rc; 1901 if (d_is_positive(new_dentry)) { 1902 new_isec = backing_inode_security(new_dentry); 1903 new_is_dir = d_is_dir(new_dentry); 1904 rc = avc_has_perm(&selinux_state, 1905 sid, new_isec->sid, 1906 new_isec->sclass, 1907 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1908 if (rc) 1909 return rc; 1910 } 1911 1912 return 0; 1913 } 1914 1915 /* Check whether a task can perform a filesystem operation. */ 1916 static int superblock_has_perm(const struct cred *cred, 1917 struct super_block *sb, 1918 u32 perms, 1919 struct common_audit_data *ad) 1920 { 1921 struct superblock_security_struct *sbsec; 1922 u32 sid = cred_sid(cred); 1923 1924 sbsec = sb->s_security; 1925 return avc_has_perm(&selinux_state, 1926 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1927 } 1928 1929 /* Convert a Linux mode and permission mask to an access vector. */ 1930 static inline u32 file_mask_to_av(int mode, int mask) 1931 { 1932 u32 av = 0; 1933 1934 if (!S_ISDIR(mode)) { 1935 if (mask & MAY_EXEC) 1936 av |= FILE__EXECUTE; 1937 if (mask & MAY_READ) 1938 av |= FILE__READ; 1939 1940 if (mask & MAY_APPEND) 1941 av |= FILE__APPEND; 1942 else if (mask & MAY_WRITE) 1943 av |= FILE__WRITE; 1944 1945 } else { 1946 if (mask & MAY_EXEC) 1947 av |= DIR__SEARCH; 1948 if (mask & MAY_WRITE) 1949 av |= DIR__WRITE; 1950 if (mask & MAY_READ) 1951 av |= DIR__READ; 1952 } 1953 1954 return av; 1955 } 1956 1957 /* Convert a Linux file to an access vector. */ 1958 static inline u32 file_to_av(struct file *file) 1959 { 1960 u32 av = 0; 1961 1962 if (file->f_mode & FMODE_READ) 1963 av |= FILE__READ; 1964 if (file->f_mode & FMODE_WRITE) { 1965 if (file->f_flags & O_APPEND) 1966 av |= FILE__APPEND; 1967 else 1968 av |= FILE__WRITE; 1969 } 1970 if (!av) { 1971 /* 1972 * Special file opened with flags 3 for ioctl-only use. 1973 */ 1974 av = FILE__IOCTL; 1975 } 1976 1977 return av; 1978 } 1979 1980 /* 1981 * Convert a file to an access vector and include the correct 1982 * open permission. 1983 */ 1984 static inline u32 open_file_to_av(struct file *file) 1985 { 1986 u32 av = file_to_av(file); 1987 struct inode *inode = file_inode(file); 1988 1989 if (selinux_policycap_openperm() && 1990 inode->i_sb->s_magic != SOCKFS_MAGIC) 1991 av |= FILE__OPEN; 1992 1993 return av; 1994 } 1995 1996 /* Hook functions begin here. */ 1997 1998 static int selinux_binder_set_context_mgr(struct task_struct *mgr) 1999 { 2000 u32 mysid = current_sid(); 2001 u32 mgrsid = task_sid(mgr); 2002 2003 return avc_has_perm(&selinux_state, 2004 mysid, mgrsid, SECCLASS_BINDER, 2005 BINDER__SET_CONTEXT_MGR, NULL); 2006 } 2007 2008 static int selinux_binder_transaction(struct task_struct *from, 2009 struct task_struct *to) 2010 { 2011 u32 mysid = current_sid(); 2012 u32 fromsid = task_sid(from); 2013 u32 tosid = task_sid(to); 2014 int rc; 2015 2016 if (mysid != fromsid) { 2017 rc = avc_has_perm(&selinux_state, 2018 mysid, fromsid, SECCLASS_BINDER, 2019 BINDER__IMPERSONATE, NULL); 2020 if (rc) 2021 return rc; 2022 } 2023 2024 return avc_has_perm(&selinux_state, 2025 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, 2026 NULL); 2027 } 2028 2029 static int selinux_binder_transfer_binder(struct task_struct *from, 2030 struct task_struct *to) 2031 { 2032 u32 fromsid = task_sid(from); 2033 u32 tosid = task_sid(to); 2034 2035 return avc_has_perm(&selinux_state, 2036 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, 2037 NULL); 2038 } 2039 2040 static int selinux_binder_transfer_file(struct task_struct *from, 2041 struct task_struct *to, 2042 struct file *file) 2043 { 2044 u32 sid = task_sid(to); 2045 struct file_security_struct *fsec = selinux_file(file); 2046 struct dentry *dentry = file->f_path.dentry; 2047 struct inode_security_struct *isec; 2048 struct common_audit_data ad; 2049 int rc; 2050 2051 ad.type = LSM_AUDIT_DATA_PATH; 2052 ad.u.path = file->f_path; 2053 2054 if (sid != fsec->sid) { 2055 rc = avc_has_perm(&selinux_state, 2056 sid, fsec->sid, 2057 SECCLASS_FD, 2058 FD__USE, 2059 &ad); 2060 if (rc) 2061 return rc; 2062 } 2063 2064 #ifdef CONFIG_BPF_SYSCALL 2065 rc = bpf_fd_pass(file, sid); 2066 if (rc) 2067 return rc; 2068 #endif 2069 2070 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2071 return 0; 2072 2073 isec = backing_inode_security(dentry); 2074 return avc_has_perm(&selinux_state, 2075 sid, isec->sid, isec->sclass, file_to_av(file), 2076 &ad); 2077 } 2078 2079 static int selinux_ptrace_access_check(struct task_struct *child, 2080 unsigned int mode) 2081 { 2082 u32 sid = current_sid(); 2083 u32 csid = task_sid(child); 2084 2085 if (mode & PTRACE_MODE_READ) 2086 return avc_has_perm(&selinux_state, 2087 sid, csid, SECCLASS_FILE, FILE__READ, NULL); 2088 2089 return avc_has_perm(&selinux_state, 2090 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2091 } 2092 2093 static int selinux_ptrace_traceme(struct task_struct *parent) 2094 { 2095 return avc_has_perm(&selinux_state, 2096 task_sid(parent), current_sid(), SECCLASS_PROCESS, 2097 PROCESS__PTRACE, NULL); 2098 } 2099 2100 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 2101 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2102 { 2103 return avc_has_perm(&selinux_state, 2104 current_sid(), task_sid(target), SECCLASS_PROCESS, 2105 PROCESS__GETCAP, NULL); 2106 } 2107 2108 static int selinux_capset(struct cred *new, const struct cred *old, 2109 const kernel_cap_t *effective, 2110 const kernel_cap_t *inheritable, 2111 const kernel_cap_t *permitted) 2112 { 2113 return avc_has_perm(&selinux_state, 2114 cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2115 PROCESS__SETCAP, NULL); 2116 } 2117 2118 /* 2119 * (This comment used to live with the selinux_task_setuid hook, 2120 * which was removed). 2121 * 2122 * Since setuid only affects the current process, and since the SELinux 2123 * controls are not based on the Linux identity attributes, SELinux does not 2124 * need to control this operation. However, SELinux does control the use of 2125 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2126 */ 2127 2128 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2129 int cap, unsigned int opts) 2130 { 2131 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2132 } 2133 2134 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2135 { 2136 const struct cred *cred = current_cred(); 2137 int rc = 0; 2138 2139 if (!sb) 2140 return 0; 2141 2142 switch (cmds) { 2143 case Q_SYNC: 2144 case Q_QUOTAON: 2145 case Q_QUOTAOFF: 2146 case Q_SETINFO: 2147 case Q_SETQUOTA: 2148 case Q_XQUOTAOFF: 2149 case Q_XQUOTAON: 2150 case Q_XSETQLIM: 2151 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2152 break; 2153 case Q_GETFMT: 2154 case Q_GETINFO: 2155 case Q_GETQUOTA: 2156 case Q_XGETQUOTA: 2157 case Q_XGETQSTAT: 2158 case Q_XGETQSTATV: 2159 case Q_XGETNEXTQUOTA: 2160 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2161 break; 2162 default: 2163 rc = 0; /* let the kernel handle invalid cmds */ 2164 break; 2165 } 2166 return rc; 2167 } 2168 2169 static int selinux_quota_on(struct dentry *dentry) 2170 { 2171 const struct cred *cred = current_cred(); 2172 2173 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2174 } 2175 2176 static int selinux_syslog(int type) 2177 { 2178 switch (type) { 2179 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2180 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2181 return avc_has_perm(&selinux_state, 2182 current_sid(), SECINITSID_KERNEL, 2183 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2184 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2185 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2186 /* Set level of messages printed to console */ 2187 case SYSLOG_ACTION_CONSOLE_LEVEL: 2188 return avc_has_perm(&selinux_state, 2189 current_sid(), SECINITSID_KERNEL, 2190 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2191 NULL); 2192 } 2193 /* All other syslog types */ 2194 return avc_has_perm(&selinux_state, 2195 current_sid(), SECINITSID_KERNEL, 2196 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2197 } 2198 2199 /* 2200 * Check that a process has enough memory to allocate a new virtual 2201 * mapping. 0 means there is enough memory for the allocation to 2202 * succeed and -ENOMEM implies there is not. 2203 * 2204 * Do not audit the selinux permission check, as this is applied to all 2205 * processes that allocate mappings. 2206 */ 2207 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2208 { 2209 int rc, cap_sys_admin = 0; 2210 2211 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2212 CAP_OPT_NOAUDIT, true); 2213 if (rc == 0) 2214 cap_sys_admin = 1; 2215 2216 return cap_sys_admin; 2217 } 2218 2219 /* binprm security operations */ 2220 2221 static u32 ptrace_parent_sid(void) 2222 { 2223 u32 sid = 0; 2224 struct task_struct *tracer; 2225 2226 rcu_read_lock(); 2227 tracer = ptrace_parent(current); 2228 if (tracer) 2229 sid = task_sid(tracer); 2230 rcu_read_unlock(); 2231 2232 return sid; 2233 } 2234 2235 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2236 const struct task_security_struct *old_tsec, 2237 const struct task_security_struct *new_tsec) 2238 { 2239 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2240 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2241 int rc; 2242 u32 av; 2243 2244 if (!nnp && !nosuid) 2245 return 0; /* neither NNP nor nosuid */ 2246 2247 if (new_tsec->sid == old_tsec->sid) 2248 return 0; /* No change in credentials */ 2249 2250 /* 2251 * If the policy enables the nnp_nosuid_transition policy capability, 2252 * then we permit transitions under NNP or nosuid if the 2253 * policy allows the corresponding permission between 2254 * the old and new contexts. 2255 */ 2256 if (selinux_policycap_nnp_nosuid_transition()) { 2257 av = 0; 2258 if (nnp) 2259 av |= PROCESS2__NNP_TRANSITION; 2260 if (nosuid) 2261 av |= PROCESS2__NOSUID_TRANSITION; 2262 rc = avc_has_perm(&selinux_state, 2263 old_tsec->sid, new_tsec->sid, 2264 SECCLASS_PROCESS2, av, NULL); 2265 if (!rc) 2266 return 0; 2267 } 2268 2269 /* 2270 * We also permit NNP or nosuid transitions to bounded SIDs, 2271 * i.e. SIDs that are guaranteed to only be allowed a subset 2272 * of the permissions of the current SID. 2273 */ 2274 rc = security_bounded_transition(&selinux_state, old_tsec->sid, 2275 new_tsec->sid); 2276 if (!rc) 2277 return 0; 2278 2279 /* 2280 * On failure, preserve the errno values for NNP vs nosuid. 2281 * NNP: Operation not permitted for caller. 2282 * nosuid: Permission denied to file. 2283 */ 2284 if (nnp) 2285 return -EPERM; 2286 return -EACCES; 2287 } 2288 2289 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2290 { 2291 const struct task_security_struct *old_tsec; 2292 struct task_security_struct *new_tsec; 2293 struct inode_security_struct *isec; 2294 struct common_audit_data ad; 2295 struct inode *inode = file_inode(bprm->file); 2296 int rc; 2297 2298 /* SELinux context only depends on initial program or script and not 2299 * the script interpreter */ 2300 2301 old_tsec = selinux_cred(current_cred()); 2302 new_tsec = selinux_cred(bprm->cred); 2303 isec = inode_security(inode); 2304 2305 /* Default to the current task SID. */ 2306 new_tsec->sid = old_tsec->sid; 2307 new_tsec->osid = old_tsec->sid; 2308 2309 /* Reset fs, key, and sock SIDs on execve. */ 2310 new_tsec->create_sid = 0; 2311 new_tsec->keycreate_sid = 0; 2312 new_tsec->sockcreate_sid = 0; 2313 2314 if (old_tsec->exec_sid) { 2315 new_tsec->sid = old_tsec->exec_sid; 2316 /* Reset exec SID on execve. */ 2317 new_tsec->exec_sid = 0; 2318 2319 /* Fail on NNP or nosuid if not an allowed transition. */ 2320 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2321 if (rc) 2322 return rc; 2323 } else { 2324 /* Check for a default transition on this program. */ 2325 rc = security_transition_sid(&selinux_state, old_tsec->sid, 2326 isec->sid, SECCLASS_PROCESS, NULL, 2327 &new_tsec->sid); 2328 if (rc) 2329 return rc; 2330 2331 /* 2332 * Fallback to old SID on NNP or nosuid if not an allowed 2333 * transition. 2334 */ 2335 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2336 if (rc) 2337 new_tsec->sid = old_tsec->sid; 2338 } 2339 2340 ad.type = LSM_AUDIT_DATA_FILE; 2341 ad.u.file = bprm->file; 2342 2343 if (new_tsec->sid == old_tsec->sid) { 2344 rc = avc_has_perm(&selinux_state, 2345 old_tsec->sid, isec->sid, 2346 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2347 if (rc) 2348 return rc; 2349 } else { 2350 /* Check permissions for the transition. */ 2351 rc = avc_has_perm(&selinux_state, 2352 old_tsec->sid, new_tsec->sid, 2353 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2354 if (rc) 2355 return rc; 2356 2357 rc = avc_has_perm(&selinux_state, 2358 new_tsec->sid, isec->sid, 2359 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2360 if (rc) 2361 return rc; 2362 2363 /* Check for shared state */ 2364 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2365 rc = avc_has_perm(&selinux_state, 2366 old_tsec->sid, new_tsec->sid, 2367 SECCLASS_PROCESS, PROCESS__SHARE, 2368 NULL); 2369 if (rc) 2370 return -EPERM; 2371 } 2372 2373 /* Make sure that anyone attempting to ptrace over a task that 2374 * changes its SID has the appropriate permit */ 2375 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2376 u32 ptsid = ptrace_parent_sid(); 2377 if (ptsid != 0) { 2378 rc = avc_has_perm(&selinux_state, 2379 ptsid, new_tsec->sid, 2380 SECCLASS_PROCESS, 2381 PROCESS__PTRACE, NULL); 2382 if (rc) 2383 return -EPERM; 2384 } 2385 } 2386 2387 /* Clear any possibly unsafe personality bits on exec: */ 2388 bprm->per_clear |= PER_CLEAR_ON_SETID; 2389 2390 /* Enable secure mode for SIDs transitions unless 2391 the noatsecure permission is granted between 2392 the two SIDs, i.e. ahp returns 0. */ 2393 rc = avc_has_perm(&selinux_state, 2394 old_tsec->sid, new_tsec->sid, 2395 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2396 NULL); 2397 bprm->secureexec |= !!rc; 2398 } 2399 2400 return 0; 2401 } 2402 2403 static int match_file(const void *p, struct file *file, unsigned fd) 2404 { 2405 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2406 } 2407 2408 /* Derived from fs/exec.c:flush_old_files. */ 2409 static inline void flush_unauthorized_files(const struct cred *cred, 2410 struct files_struct *files) 2411 { 2412 struct file *file, *devnull = NULL; 2413 struct tty_struct *tty; 2414 int drop_tty = 0; 2415 unsigned n; 2416 2417 tty = get_current_tty(); 2418 if (tty) { 2419 spin_lock(&tty->files_lock); 2420 if (!list_empty(&tty->tty_files)) { 2421 struct tty_file_private *file_priv; 2422 2423 /* Revalidate access to controlling tty. 2424 Use file_path_has_perm on the tty path directly 2425 rather than using file_has_perm, as this particular 2426 open file may belong to another process and we are 2427 only interested in the inode-based check here. */ 2428 file_priv = list_first_entry(&tty->tty_files, 2429 struct tty_file_private, list); 2430 file = file_priv->file; 2431 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2432 drop_tty = 1; 2433 } 2434 spin_unlock(&tty->files_lock); 2435 tty_kref_put(tty); 2436 } 2437 /* Reset controlling tty. */ 2438 if (drop_tty) 2439 no_tty(); 2440 2441 /* Revalidate access to inherited open files. */ 2442 n = iterate_fd(files, 0, match_file, cred); 2443 if (!n) /* none found? */ 2444 return; 2445 2446 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2447 if (IS_ERR(devnull)) 2448 devnull = NULL; 2449 /* replace all the matching ones with this */ 2450 do { 2451 replace_fd(n - 1, devnull, 0); 2452 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2453 if (devnull) 2454 fput(devnull); 2455 } 2456 2457 /* 2458 * Prepare a process for imminent new credential changes due to exec 2459 */ 2460 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2461 { 2462 struct task_security_struct *new_tsec; 2463 struct rlimit *rlim, *initrlim; 2464 int rc, i; 2465 2466 new_tsec = selinux_cred(bprm->cred); 2467 if (new_tsec->sid == new_tsec->osid) 2468 return; 2469 2470 /* Close files for which the new task SID is not authorized. */ 2471 flush_unauthorized_files(bprm->cred, current->files); 2472 2473 /* Always clear parent death signal on SID transitions. */ 2474 current->pdeath_signal = 0; 2475 2476 /* Check whether the new SID can inherit resource limits from the old 2477 * SID. If not, reset all soft limits to the lower of the current 2478 * task's hard limit and the init task's soft limit. 2479 * 2480 * Note that the setting of hard limits (even to lower them) can be 2481 * controlled by the setrlimit check. The inclusion of the init task's 2482 * soft limit into the computation is to avoid resetting soft limits 2483 * higher than the default soft limit for cases where the default is 2484 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2485 */ 2486 rc = avc_has_perm(&selinux_state, 2487 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2488 PROCESS__RLIMITINH, NULL); 2489 if (rc) { 2490 /* protect against do_prlimit() */ 2491 task_lock(current); 2492 for (i = 0; i < RLIM_NLIMITS; i++) { 2493 rlim = current->signal->rlim + i; 2494 initrlim = init_task.signal->rlim + i; 2495 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2496 } 2497 task_unlock(current); 2498 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2499 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2500 } 2501 } 2502 2503 /* 2504 * Clean up the process immediately after the installation of new credentials 2505 * due to exec 2506 */ 2507 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2508 { 2509 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2510 u32 osid, sid; 2511 int rc; 2512 2513 osid = tsec->osid; 2514 sid = tsec->sid; 2515 2516 if (sid == osid) 2517 return; 2518 2519 /* Check whether the new SID can inherit signal state from the old SID. 2520 * If not, clear itimers to avoid subsequent signal generation and 2521 * flush and unblock signals. 2522 * 2523 * This must occur _after_ the task SID has been updated so that any 2524 * kill done after the flush will be checked against the new SID. 2525 */ 2526 rc = avc_has_perm(&selinux_state, 2527 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2528 if (rc) { 2529 clear_itimer(); 2530 2531 spin_lock_irq(¤t->sighand->siglock); 2532 if (!fatal_signal_pending(current)) { 2533 flush_sigqueue(¤t->pending); 2534 flush_sigqueue(¤t->signal->shared_pending); 2535 flush_signal_handlers(current, 1); 2536 sigemptyset(¤t->blocked); 2537 recalc_sigpending(); 2538 } 2539 spin_unlock_irq(¤t->sighand->siglock); 2540 } 2541 2542 /* Wake up the parent if it is waiting so that it can recheck 2543 * wait permission to the new task SID. */ 2544 read_lock(&tasklist_lock); 2545 __wake_up_parent(current, current->real_parent); 2546 read_unlock(&tasklist_lock); 2547 } 2548 2549 /* superblock security operations */ 2550 2551 static int selinux_sb_alloc_security(struct super_block *sb) 2552 { 2553 struct superblock_security_struct *sbsec; 2554 2555 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 2556 if (!sbsec) 2557 return -ENOMEM; 2558 2559 mutex_init(&sbsec->lock); 2560 INIT_LIST_HEAD(&sbsec->isec_head); 2561 spin_lock_init(&sbsec->isec_lock); 2562 sbsec->sb = sb; 2563 sbsec->sid = SECINITSID_UNLABELED; 2564 sbsec->def_sid = SECINITSID_FILE; 2565 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2566 sb->s_security = sbsec; 2567 2568 return 0; 2569 } 2570 2571 static void selinux_sb_free_security(struct super_block *sb) 2572 { 2573 superblock_free_security(sb); 2574 } 2575 2576 static inline int opt_len(const char *s) 2577 { 2578 bool open_quote = false; 2579 int len; 2580 char c; 2581 2582 for (len = 0; (c = s[len]) != '\0'; len++) { 2583 if (c == '"') 2584 open_quote = !open_quote; 2585 if (c == ',' && !open_quote) 2586 break; 2587 } 2588 return len; 2589 } 2590 2591 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2592 { 2593 char *from = options; 2594 char *to = options; 2595 bool first = true; 2596 int rc; 2597 2598 while (1) { 2599 int len = opt_len(from); 2600 int token; 2601 char *arg = NULL; 2602 2603 token = match_opt_prefix(from, len, &arg); 2604 2605 if (token != Opt_error) { 2606 char *p, *q; 2607 2608 /* strip quotes */ 2609 if (arg) { 2610 for (p = q = arg; p < from + len; p++) { 2611 char c = *p; 2612 if (c != '"') 2613 *q++ = c; 2614 } 2615 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2616 if (!arg) { 2617 rc = -ENOMEM; 2618 goto free_opt; 2619 } 2620 } 2621 rc = selinux_add_opt(token, arg, mnt_opts); 2622 if (unlikely(rc)) { 2623 kfree(arg); 2624 goto free_opt; 2625 } 2626 } else { 2627 if (!first) { // copy with preceding comma 2628 from--; 2629 len++; 2630 } 2631 if (to != from) 2632 memmove(to, from, len); 2633 to += len; 2634 first = false; 2635 } 2636 if (!from[len]) 2637 break; 2638 from += len + 1; 2639 } 2640 *to = '\0'; 2641 return 0; 2642 2643 free_opt: 2644 if (*mnt_opts) { 2645 selinux_free_mnt_opts(*mnt_opts); 2646 *mnt_opts = NULL; 2647 } 2648 return rc; 2649 } 2650 2651 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2652 { 2653 struct selinux_mnt_opts *opts = mnt_opts; 2654 struct superblock_security_struct *sbsec = sb->s_security; 2655 u32 sid; 2656 int rc; 2657 2658 if (!(sbsec->flags & SE_SBINITIALIZED)) 2659 return 0; 2660 2661 if (!opts) 2662 return 0; 2663 2664 if (opts->fscontext) { 2665 rc = parse_sid(sb, opts->fscontext, &sid); 2666 if (rc) 2667 return rc; 2668 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2669 goto out_bad_option; 2670 } 2671 if (opts->context) { 2672 rc = parse_sid(sb, opts->context, &sid); 2673 if (rc) 2674 return rc; 2675 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2676 goto out_bad_option; 2677 } 2678 if (opts->rootcontext) { 2679 struct inode_security_struct *root_isec; 2680 root_isec = backing_inode_security(sb->s_root); 2681 rc = parse_sid(sb, opts->rootcontext, &sid); 2682 if (rc) 2683 return rc; 2684 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2685 goto out_bad_option; 2686 } 2687 if (opts->defcontext) { 2688 rc = parse_sid(sb, opts->defcontext, &sid); 2689 if (rc) 2690 return rc; 2691 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2692 goto out_bad_option; 2693 } 2694 return 0; 2695 2696 out_bad_option: 2697 pr_warn("SELinux: unable to change security options " 2698 "during remount (dev %s, type=%s)\n", sb->s_id, 2699 sb->s_type->name); 2700 return -EINVAL; 2701 } 2702 2703 static int selinux_sb_kern_mount(struct super_block *sb) 2704 { 2705 const struct cred *cred = current_cred(); 2706 struct common_audit_data ad; 2707 2708 ad.type = LSM_AUDIT_DATA_DENTRY; 2709 ad.u.dentry = sb->s_root; 2710 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2711 } 2712 2713 static int selinux_sb_statfs(struct dentry *dentry) 2714 { 2715 const struct cred *cred = current_cred(); 2716 struct common_audit_data ad; 2717 2718 ad.type = LSM_AUDIT_DATA_DENTRY; 2719 ad.u.dentry = dentry->d_sb->s_root; 2720 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2721 } 2722 2723 static int selinux_mount(const char *dev_name, 2724 const struct path *path, 2725 const char *type, 2726 unsigned long flags, 2727 void *data) 2728 { 2729 const struct cred *cred = current_cred(); 2730 2731 if (flags & MS_REMOUNT) 2732 return superblock_has_perm(cred, path->dentry->d_sb, 2733 FILESYSTEM__REMOUNT, NULL); 2734 else 2735 return path_has_perm(cred, path, FILE__MOUNTON); 2736 } 2737 2738 static int selinux_move_mount(const struct path *from_path, 2739 const struct path *to_path) 2740 { 2741 const struct cred *cred = current_cred(); 2742 2743 return path_has_perm(cred, to_path, FILE__MOUNTON); 2744 } 2745 2746 static int selinux_umount(struct vfsmount *mnt, int flags) 2747 { 2748 const struct cred *cred = current_cred(); 2749 2750 return superblock_has_perm(cred, mnt->mnt_sb, 2751 FILESYSTEM__UNMOUNT, NULL); 2752 } 2753 2754 static int selinux_fs_context_dup(struct fs_context *fc, 2755 struct fs_context *src_fc) 2756 { 2757 const struct selinux_mnt_opts *src = src_fc->security; 2758 struct selinux_mnt_opts *opts; 2759 2760 if (!src) 2761 return 0; 2762 2763 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 2764 if (!fc->security) 2765 return -ENOMEM; 2766 2767 opts = fc->security; 2768 2769 if (src->fscontext) { 2770 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); 2771 if (!opts->fscontext) 2772 return -ENOMEM; 2773 } 2774 if (src->context) { 2775 opts->context = kstrdup(src->context, GFP_KERNEL); 2776 if (!opts->context) 2777 return -ENOMEM; 2778 } 2779 if (src->rootcontext) { 2780 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); 2781 if (!opts->rootcontext) 2782 return -ENOMEM; 2783 } 2784 if (src->defcontext) { 2785 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); 2786 if (!opts->defcontext) 2787 return -ENOMEM; 2788 } 2789 return 0; 2790 } 2791 2792 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2793 fsparam_string(CONTEXT_STR, Opt_context), 2794 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2795 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2796 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2797 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2798 {} 2799 }; 2800 2801 static int selinux_fs_context_parse_param(struct fs_context *fc, 2802 struct fs_parameter *param) 2803 { 2804 struct fs_parse_result result; 2805 int opt, rc; 2806 2807 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2808 if (opt < 0) 2809 return opt; 2810 2811 rc = selinux_add_opt(opt, param->string, &fc->security); 2812 if (!rc) { 2813 param->string = NULL; 2814 rc = 1; 2815 } 2816 return rc; 2817 } 2818 2819 /* inode security operations */ 2820 2821 static int selinux_inode_alloc_security(struct inode *inode) 2822 { 2823 struct inode_security_struct *isec = selinux_inode(inode); 2824 u32 sid = current_sid(); 2825 2826 spin_lock_init(&isec->lock); 2827 INIT_LIST_HEAD(&isec->list); 2828 isec->inode = inode; 2829 isec->sid = SECINITSID_UNLABELED; 2830 isec->sclass = SECCLASS_FILE; 2831 isec->task_sid = sid; 2832 isec->initialized = LABEL_INVALID; 2833 2834 return 0; 2835 } 2836 2837 static void selinux_inode_free_security(struct inode *inode) 2838 { 2839 inode_free_security(inode); 2840 } 2841 2842 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2843 const struct qstr *name, void **ctx, 2844 u32 *ctxlen) 2845 { 2846 u32 newsid; 2847 int rc; 2848 2849 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2850 d_inode(dentry->d_parent), name, 2851 inode_mode_to_security_class(mode), 2852 &newsid); 2853 if (rc) 2854 return rc; 2855 2856 return security_sid_to_context(&selinux_state, newsid, (char **)ctx, 2857 ctxlen); 2858 } 2859 2860 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2861 struct qstr *name, 2862 const struct cred *old, 2863 struct cred *new) 2864 { 2865 u32 newsid; 2866 int rc; 2867 struct task_security_struct *tsec; 2868 2869 rc = selinux_determine_inode_label(selinux_cred(old), 2870 d_inode(dentry->d_parent), name, 2871 inode_mode_to_security_class(mode), 2872 &newsid); 2873 if (rc) 2874 return rc; 2875 2876 tsec = selinux_cred(new); 2877 tsec->create_sid = newsid; 2878 return 0; 2879 } 2880 2881 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2882 const struct qstr *qstr, 2883 const char **name, 2884 void **value, size_t *len) 2885 { 2886 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2887 struct superblock_security_struct *sbsec; 2888 u32 newsid, clen; 2889 int rc; 2890 char *context; 2891 2892 sbsec = dir->i_sb->s_security; 2893 2894 newsid = tsec->create_sid; 2895 2896 rc = selinux_determine_inode_label(tsec, dir, qstr, 2897 inode_mode_to_security_class(inode->i_mode), 2898 &newsid); 2899 if (rc) 2900 return rc; 2901 2902 /* Possibly defer initialization to selinux_complete_init. */ 2903 if (sbsec->flags & SE_SBINITIALIZED) { 2904 struct inode_security_struct *isec = selinux_inode(inode); 2905 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2906 isec->sid = newsid; 2907 isec->initialized = LABEL_INITIALIZED; 2908 } 2909 2910 if (!selinux_initialized(&selinux_state) || 2911 !(sbsec->flags & SBLABEL_MNT)) 2912 return -EOPNOTSUPP; 2913 2914 if (name) 2915 *name = XATTR_SELINUX_SUFFIX; 2916 2917 if (value && len) { 2918 rc = security_sid_to_context_force(&selinux_state, newsid, 2919 &context, &clen); 2920 if (rc) 2921 return rc; 2922 *value = context; 2923 *len = clen; 2924 } 2925 2926 return 0; 2927 } 2928 2929 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 2930 { 2931 return may_create(dir, dentry, SECCLASS_FILE); 2932 } 2933 2934 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2935 { 2936 return may_link(dir, old_dentry, MAY_LINK); 2937 } 2938 2939 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2940 { 2941 return may_link(dir, dentry, MAY_UNLINK); 2942 } 2943 2944 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2945 { 2946 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2947 } 2948 2949 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 2950 { 2951 return may_create(dir, dentry, SECCLASS_DIR); 2952 } 2953 2954 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2955 { 2956 return may_link(dir, dentry, MAY_RMDIR); 2957 } 2958 2959 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 2960 { 2961 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2962 } 2963 2964 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2965 struct inode *new_inode, struct dentry *new_dentry) 2966 { 2967 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2968 } 2969 2970 static int selinux_inode_readlink(struct dentry *dentry) 2971 { 2972 const struct cred *cred = current_cred(); 2973 2974 return dentry_has_perm(cred, dentry, FILE__READ); 2975 } 2976 2977 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 2978 bool rcu) 2979 { 2980 const struct cred *cred = current_cred(); 2981 struct common_audit_data ad; 2982 struct inode_security_struct *isec; 2983 u32 sid; 2984 2985 validate_creds(cred); 2986 2987 ad.type = LSM_AUDIT_DATA_DENTRY; 2988 ad.u.dentry = dentry; 2989 sid = cred_sid(cred); 2990 isec = inode_security_rcu(inode, rcu); 2991 if (IS_ERR(isec)) 2992 return PTR_ERR(isec); 2993 2994 return avc_has_perm_flags(&selinux_state, 2995 sid, isec->sid, isec->sclass, FILE__READ, &ad, 2996 rcu ? MAY_NOT_BLOCK : 0); 2997 } 2998 2999 static noinline int audit_inode_permission(struct inode *inode, 3000 u32 perms, u32 audited, u32 denied, 3001 int result) 3002 { 3003 struct common_audit_data ad; 3004 struct inode_security_struct *isec = selinux_inode(inode); 3005 int rc; 3006 3007 ad.type = LSM_AUDIT_DATA_INODE; 3008 ad.u.inode = inode; 3009 3010 rc = slow_avc_audit(&selinux_state, 3011 current_sid(), isec->sid, isec->sclass, perms, 3012 audited, denied, result, &ad); 3013 if (rc) 3014 return rc; 3015 return 0; 3016 } 3017 3018 static int selinux_inode_permission(struct inode *inode, int mask) 3019 { 3020 const struct cred *cred = current_cred(); 3021 u32 perms; 3022 bool from_access; 3023 bool no_block = mask & MAY_NOT_BLOCK; 3024 struct inode_security_struct *isec; 3025 u32 sid; 3026 struct av_decision avd; 3027 int rc, rc2; 3028 u32 audited, denied; 3029 3030 from_access = mask & MAY_ACCESS; 3031 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3032 3033 /* No permission to check. Existence test. */ 3034 if (!mask) 3035 return 0; 3036 3037 validate_creds(cred); 3038 3039 if (unlikely(IS_PRIVATE(inode))) 3040 return 0; 3041 3042 perms = file_mask_to_av(inode->i_mode, mask); 3043 3044 sid = cred_sid(cred); 3045 isec = inode_security_rcu(inode, no_block); 3046 if (IS_ERR(isec)) 3047 return PTR_ERR(isec); 3048 3049 rc = avc_has_perm_noaudit(&selinux_state, 3050 sid, isec->sid, isec->sclass, perms, 3051 no_block ? AVC_NONBLOCKING : 0, 3052 &avd); 3053 audited = avc_audit_required(perms, &avd, rc, 3054 from_access ? FILE__AUDIT_ACCESS : 0, 3055 &denied); 3056 if (likely(!audited)) 3057 return rc; 3058 3059 /* fall back to ref-walk if we have to generate audit */ 3060 if (no_block) 3061 return -ECHILD; 3062 3063 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3064 if (rc2) 3065 return rc2; 3066 return rc; 3067 } 3068 3069 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3070 { 3071 const struct cred *cred = current_cred(); 3072 struct inode *inode = d_backing_inode(dentry); 3073 unsigned int ia_valid = iattr->ia_valid; 3074 __u32 av = FILE__WRITE; 3075 3076 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3077 if (ia_valid & ATTR_FORCE) { 3078 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3079 ATTR_FORCE); 3080 if (!ia_valid) 3081 return 0; 3082 } 3083 3084 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3085 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3086 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3087 3088 if (selinux_policycap_openperm() && 3089 inode->i_sb->s_magic != SOCKFS_MAGIC && 3090 (ia_valid & ATTR_SIZE) && 3091 !(ia_valid & ATTR_FILE)) 3092 av |= FILE__OPEN; 3093 3094 return dentry_has_perm(cred, dentry, av); 3095 } 3096 3097 static int selinux_inode_getattr(const struct path *path) 3098 { 3099 return path_has_perm(current_cred(), path, FILE__GETATTR); 3100 } 3101 3102 static bool has_cap_mac_admin(bool audit) 3103 { 3104 const struct cred *cred = current_cred(); 3105 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3106 3107 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3108 return false; 3109 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3110 return false; 3111 return true; 3112 } 3113 3114 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 3115 const void *value, size_t size, int flags) 3116 { 3117 struct inode *inode = d_backing_inode(dentry); 3118 struct inode_security_struct *isec; 3119 struct superblock_security_struct *sbsec; 3120 struct common_audit_data ad; 3121 u32 newsid, sid = current_sid(); 3122 int rc = 0; 3123 3124 if (strcmp(name, XATTR_NAME_SELINUX)) { 3125 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3126 if (rc) 3127 return rc; 3128 3129 /* Not an attribute we recognize, so just check the 3130 ordinary setattr permission. */ 3131 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3132 } 3133 3134 if (!selinux_initialized(&selinux_state)) 3135 return (inode_owner_or_capable(inode) ? 0 : -EPERM); 3136 3137 sbsec = inode->i_sb->s_security; 3138 if (!(sbsec->flags & SBLABEL_MNT)) 3139 return -EOPNOTSUPP; 3140 3141 if (!inode_owner_or_capable(inode)) 3142 return -EPERM; 3143 3144 ad.type = LSM_AUDIT_DATA_DENTRY; 3145 ad.u.dentry = dentry; 3146 3147 isec = backing_inode_security(dentry); 3148 rc = avc_has_perm(&selinux_state, 3149 sid, isec->sid, isec->sclass, 3150 FILE__RELABELFROM, &ad); 3151 if (rc) 3152 return rc; 3153 3154 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3155 GFP_KERNEL); 3156 if (rc == -EINVAL) { 3157 if (!has_cap_mac_admin(true)) { 3158 struct audit_buffer *ab; 3159 size_t audit_size; 3160 3161 /* We strip a nul only if it is at the end, otherwise the 3162 * context contains a nul and we should audit that */ 3163 if (value) { 3164 const char *str = value; 3165 3166 if (str[size - 1] == '\0') 3167 audit_size = size - 1; 3168 else 3169 audit_size = size; 3170 } else { 3171 audit_size = 0; 3172 } 3173 ab = audit_log_start(audit_context(), 3174 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3175 audit_log_format(ab, "op=setxattr invalid_context="); 3176 audit_log_n_untrustedstring(ab, value, audit_size); 3177 audit_log_end(ab); 3178 3179 return rc; 3180 } 3181 rc = security_context_to_sid_force(&selinux_state, value, 3182 size, &newsid); 3183 } 3184 if (rc) 3185 return rc; 3186 3187 rc = avc_has_perm(&selinux_state, 3188 sid, newsid, isec->sclass, 3189 FILE__RELABELTO, &ad); 3190 if (rc) 3191 return rc; 3192 3193 rc = security_validate_transition(&selinux_state, isec->sid, newsid, 3194 sid, isec->sclass); 3195 if (rc) 3196 return rc; 3197 3198 return avc_has_perm(&selinux_state, 3199 newsid, 3200 sbsec->sid, 3201 SECCLASS_FILESYSTEM, 3202 FILESYSTEM__ASSOCIATE, 3203 &ad); 3204 } 3205 3206 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3207 const void *value, size_t size, 3208 int flags) 3209 { 3210 struct inode *inode = d_backing_inode(dentry); 3211 struct inode_security_struct *isec; 3212 u32 newsid; 3213 int rc; 3214 3215 if (strcmp(name, XATTR_NAME_SELINUX)) { 3216 /* Not an attribute we recognize, so nothing to do. */ 3217 return; 3218 } 3219 3220 if (!selinux_initialized(&selinux_state)) { 3221 /* If we haven't even been initialized, then we can't validate 3222 * against a policy, so leave the label as invalid. It may 3223 * resolve to a valid label on the next revalidation try if 3224 * we've since initialized. 3225 */ 3226 return; 3227 } 3228 3229 rc = security_context_to_sid_force(&selinux_state, value, size, 3230 &newsid); 3231 if (rc) { 3232 pr_err("SELinux: unable to map context to SID" 3233 "for (%s, %lu), rc=%d\n", 3234 inode->i_sb->s_id, inode->i_ino, -rc); 3235 return; 3236 } 3237 3238 isec = backing_inode_security(dentry); 3239 spin_lock(&isec->lock); 3240 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3241 isec->sid = newsid; 3242 isec->initialized = LABEL_INITIALIZED; 3243 spin_unlock(&isec->lock); 3244 3245 return; 3246 } 3247 3248 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3249 { 3250 const struct cred *cred = current_cred(); 3251 3252 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3253 } 3254 3255 static int selinux_inode_listxattr(struct dentry *dentry) 3256 { 3257 const struct cred *cred = current_cred(); 3258 3259 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3260 } 3261 3262 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 3263 { 3264 if (strcmp(name, XATTR_NAME_SELINUX)) { 3265 int rc = cap_inode_removexattr(dentry, name); 3266 if (rc) 3267 return rc; 3268 3269 /* Not an attribute we recognize, so just check the 3270 ordinary setattr permission. */ 3271 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3272 } 3273 3274 if (!selinux_initialized(&selinux_state)) 3275 return 0; 3276 3277 /* No one is allowed to remove a SELinux security label. 3278 You can change the label, but all data must be labeled. */ 3279 return -EACCES; 3280 } 3281 3282 static int selinux_path_notify(const struct path *path, u64 mask, 3283 unsigned int obj_type) 3284 { 3285 int ret; 3286 u32 perm; 3287 3288 struct common_audit_data ad; 3289 3290 ad.type = LSM_AUDIT_DATA_PATH; 3291 ad.u.path = *path; 3292 3293 /* 3294 * Set permission needed based on the type of mark being set. 3295 * Performs an additional check for sb watches. 3296 */ 3297 switch (obj_type) { 3298 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3299 perm = FILE__WATCH_MOUNT; 3300 break; 3301 case FSNOTIFY_OBJ_TYPE_SB: 3302 perm = FILE__WATCH_SB; 3303 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3304 FILESYSTEM__WATCH, &ad); 3305 if (ret) 3306 return ret; 3307 break; 3308 case FSNOTIFY_OBJ_TYPE_INODE: 3309 perm = FILE__WATCH; 3310 break; 3311 default: 3312 return -EINVAL; 3313 } 3314 3315 /* blocking watches require the file:watch_with_perm permission */ 3316 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3317 perm |= FILE__WATCH_WITH_PERM; 3318 3319 /* watches on read-like events need the file:watch_reads permission */ 3320 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3321 perm |= FILE__WATCH_READS; 3322 3323 return path_has_perm(current_cred(), path, perm); 3324 } 3325 3326 /* 3327 * Copy the inode security context value to the user. 3328 * 3329 * Permission check is handled by selinux_inode_getxattr hook. 3330 */ 3331 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) 3332 { 3333 u32 size; 3334 int error; 3335 char *context = NULL; 3336 struct inode_security_struct *isec; 3337 3338 /* 3339 * If we're not initialized yet, then we can't validate contexts, so 3340 * just let vfs_getxattr fall back to using the on-disk xattr. 3341 */ 3342 if (!selinux_initialized(&selinux_state) || 3343 strcmp(name, XATTR_SELINUX_SUFFIX)) 3344 return -EOPNOTSUPP; 3345 3346 /* 3347 * If the caller has CAP_MAC_ADMIN, then get the raw context 3348 * value even if it is not defined by current policy; otherwise, 3349 * use the in-core value under current policy. 3350 * Use the non-auditing forms of the permission checks since 3351 * getxattr may be called by unprivileged processes commonly 3352 * and lack of permission just means that we fall back to the 3353 * in-core context value, not a denial. 3354 */ 3355 isec = inode_security(inode); 3356 if (has_cap_mac_admin(false)) 3357 error = security_sid_to_context_force(&selinux_state, 3358 isec->sid, &context, 3359 &size); 3360 else 3361 error = security_sid_to_context(&selinux_state, isec->sid, 3362 &context, &size); 3363 if (error) 3364 return error; 3365 error = size; 3366 if (alloc) { 3367 *buffer = context; 3368 goto out_nofree; 3369 } 3370 kfree(context); 3371 out_nofree: 3372 return error; 3373 } 3374 3375 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3376 const void *value, size_t size, int flags) 3377 { 3378 struct inode_security_struct *isec = inode_security_novalidate(inode); 3379 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 3380 u32 newsid; 3381 int rc; 3382 3383 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3384 return -EOPNOTSUPP; 3385 3386 if (!(sbsec->flags & SBLABEL_MNT)) 3387 return -EOPNOTSUPP; 3388 3389 if (!value || !size) 3390 return -EACCES; 3391 3392 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3393 GFP_KERNEL); 3394 if (rc) 3395 return rc; 3396 3397 spin_lock(&isec->lock); 3398 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3399 isec->sid = newsid; 3400 isec->initialized = LABEL_INITIALIZED; 3401 spin_unlock(&isec->lock); 3402 return 0; 3403 } 3404 3405 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3406 { 3407 const int len = sizeof(XATTR_NAME_SELINUX); 3408 if (buffer && len <= buffer_size) 3409 memcpy(buffer, XATTR_NAME_SELINUX, len); 3410 return len; 3411 } 3412 3413 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3414 { 3415 struct inode_security_struct *isec = inode_security_novalidate(inode); 3416 *secid = isec->sid; 3417 } 3418 3419 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3420 { 3421 u32 sid; 3422 struct task_security_struct *tsec; 3423 struct cred *new_creds = *new; 3424 3425 if (new_creds == NULL) { 3426 new_creds = prepare_creds(); 3427 if (!new_creds) 3428 return -ENOMEM; 3429 } 3430 3431 tsec = selinux_cred(new_creds); 3432 /* Get label from overlay inode and set it in create_sid */ 3433 selinux_inode_getsecid(d_inode(src), &sid); 3434 tsec->create_sid = sid; 3435 *new = new_creds; 3436 return 0; 3437 } 3438 3439 static int selinux_inode_copy_up_xattr(const char *name) 3440 { 3441 /* The copy_up hook above sets the initial context on an inode, but we 3442 * don't then want to overwrite it by blindly copying all the lower 3443 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3444 */ 3445 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3446 return 1; /* Discard */ 3447 /* 3448 * Any other attribute apart from SELINUX is not claimed, supported 3449 * by selinux. 3450 */ 3451 return -EOPNOTSUPP; 3452 } 3453 3454 /* kernfs node operations */ 3455 3456 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3457 struct kernfs_node *kn) 3458 { 3459 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3460 u32 parent_sid, newsid, clen; 3461 int rc; 3462 char *context; 3463 3464 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3465 if (rc == -ENODATA) 3466 return 0; 3467 else if (rc < 0) 3468 return rc; 3469 3470 clen = (u32)rc; 3471 context = kmalloc(clen, GFP_KERNEL); 3472 if (!context) 3473 return -ENOMEM; 3474 3475 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3476 if (rc < 0) { 3477 kfree(context); 3478 return rc; 3479 } 3480 3481 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, 3482 GFP_KERNEL); 3483 kfree(context); 3484 if (rc) 3485 return rc; 3486 3487 if (tsec->create_sid) { 3488 newsid = tsec->create_sid; 3489 } else { 3490 u16 secclass = inode_mode_to_security_class(kn->mode); 3491 struct qstr q; 3492 3493 q.name = kn->name; 3494 q.hash_len = hashlen_string(kn_dir, kn->name); 3495 3496 rc = security_transition_sid(&selinux_state, tsec->sid, 3497 parent_sid, secclass, &q, 3498 &newsid); 3499 if (rc) 3500 return rc; 3501 } 3502 3503 rc = security_sid_to_context_force(&selinux_state, newsid, 3504 &context, &clen); 3505 if (rc) 3506 return rc; 3507 3508 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3509 XATTR_CREATE); 3510 kfree(context); 3511 return rc; 3512 } 3513 3514 3515 /* file security operations */ 3516 3517 static int selinux_revalidate_file_permission(struct file *file, int mask) 3518 { 3519 const struct cred *cred = current_cred(); 3520 struct inode *inode = file_inode(file); 3521 3522 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3523 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3524 mask |= MAY_APPEND; 3525 3526 return file_has_perm(cred, file, 3527 file_mask_to_av(inode->i_mode, mask)); 3528 } 3529 3530 static int selinux_file_permission(struct file *file, int mask) 3531 { 3532 struct inode *inode = file_inode(file); 3533 struct file_security_struct *fsec = selinux_file(file); 3534 struct inode_security_struct *isec; 3535 u32 sid = current_sid(); 3536 3537 if (!mask) 3538 /* No permission to check. Existence test. */ 3539 return 0; 3540 3541 isec = inode_security(inode); 3542 if (sid == fsec->sid && fsec->isid == isec->sid && 3543 fsec->pseqno == avc_policy_seqno(&selinux_state)) 3544 /* No change since file_open check. */ 3545 return 0; 3546 3547 return selinux_revalidate_file_permission(file, mask); 3548 } 3549 3550 static int selinux_file_alloc_security(struct file *file) 3551 { 3552 struct file_security_struct *fsec = selinux_file(file); 3553 u32 sid = current_sid(); 3554 3555 fsec->sid = sid; 3556 fsec->fown_sid = sid; 3557 3558 return 0; 3559 } 3560 3561 /* 3562 * Check whether a task has the ioctl permission and cmd 3563 * operation to an inode. 3564 */ 3565 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3566 u32 requested, u16 cmd) 3567 { 3568 struct common_audit_data ad; 3569 struct file_security_struct *fsec = selinux_file(file); 3570 struct inode *inode = file_inode(file); 3571 struct inode_security_struct *isec; 3572 struct lsm_ioctlop_audit ioctl; 3573 u32 ssid = cred_sid(cred); 3574 int rc; 3575 u8 driver = cmd >> 8; 3576 u8 xperm = cmd & 0xff; 3577 3578 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3579 ad.u.op = &ioctl; 3580 ad.u.op->cmd = cmd; 3581 ad.u.op->path = file->f_path; 3582 3583 if (ssid != fsec->sid) { 3584 rc = avc_has_perm(&selinux_state, 3585 ssid, fsec->sid, 3586 SECCLASS_FD, 3587 FD__USE, 3588 &ad); 3589 if (rc) 3590 goto out; 3591 } 3592 3593 if (unlikely(IS_PRIVATE(inode))) 3594 return 0; 3595 3596 isec = inode_security(inode); 3597 rc = avc_has_extended_perms(&selinux_state, 3598 ssid, isec->sid, isec->sclass, 3599 requested, driver, xperm, &ad); 3600 out: 3601 return rc; 3602 } 3603 3604 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3605 unsigned long arg) 3606 { 3607 const struct cred *cred = current_cred(); 3608 int error = 0; 3609 3610 switch (cmd) { 3611 case FIONREAD: 3612 /* fall through */ 3613 case FIBMAP: 3614 /* fall through */ 3615 case FIGETBSZ: 3616 /* fall through */ 3617 case FS_IOC_GETFLAGS: 3618 /* fall through */ 3619 case FS_IOC_GETVERSION: 3620 error = file_has_perm(cred, file, FILE__GETATTR); 3621 break; 3622 3623 case FS_IOC_SETFLAGS: 3624 /* fall through */ 3625 case FS_IOC_SETVERSION: 3626 error = file_has_perm(cred, file, FILE__SETATTR); 3627 break; 3628 3629 /* sys_ioctl() checks */ 3630 case FIONBIO: 3631 /* fall through */ 3632 case FIOASYNC: 3633 error = file_has_perm(cred, file, 0); 3634 break; 3635 3636 case KDSKBENT: 3637 case KDSKBSENT: 3638 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3639 CAP_OPT_NONE, true); 3640 break; 3641 3642 /* default case assumes that the command will go 3643 * to the file's ioctl() function. 3644 */ 3645 default: 3646 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3647 } 3648 return error; 3649 } 3650 3651 static int default_noexec __ro_after_init; 3652 3653 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3654 { 3655 const struct cred *cred = current_cred(); 3656 u32 sid = cred_sid(cred); 3657 int rc = 0; 3658 3659 if (default_noexec && 3660 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3661 (!shared && (prot & PROT_WRITE)))) { 3662 /* 3663 * We are making executable an anonymous mapping or a 3664 * private file mapping that will also be writable. 3665 * This has an additional check. 3666 */ 3667 rc = avc_has_perm(&selinux_state, 3668 sid, sid, SECCLASS_PROCESS, 3669 PROCESS__EXECMEM, NULL); 3670 if (rc) 3671 goto error; 3672 } 3673 3674 if (file) { 3675 /* read access is always possible with a mapping */ 3676 u32 av = FILE__READ; 3677 3678 /* write access only matters if the mapping is shared */ 3679 if (shared && (prot & PROT_WRITE)) 3680 av |= FILE__WRITE; 3681 3682 if (prot & PROT_EXEC) 3683 av |= FILE__EXECUTE; 3684 3685 return file_has_perm(cred, file, av); 3686 } 3687 3688 error: 3689 return rc; 3690 } 3691 3692 static int selinux_mmap_addr(unsigned long addr) 3693 { 3694 int rc = 0; 3695 3696 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3697 u32 sid = current_sid(); 3698 rc = avc_has_perm(&selinux_state, 3699 sid, sid, SECCLASS_MEMPROTECT, 3700 MEMPROTECT__MMAP_ZERO, NULL); 3701 } 3702 3703 return rc; 3704 } 3705 3706 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3707 unsigned long prot, unsigned long flags) 3708 { 3709 struct common_audit_data ad; 3710 int rc; 3711 3712 if (file) { 3713 ad.type = LSM_AUDIT_DATA_FILE; 3714 ad.u.file = file; 3715 rc = inode_has_perm(current_cred(), file_inode(file), 3716 FILE__MAP, &ad); 3717 if (rc) 3718 return rc; 3719 } 3720 3721 if (selinux_state.checkreqprot) 3722 prot = reqprot; 3723 3724 return file_map_prot_check(file, prot, 3725 (flags & MAP_TYPE) == MAP_SHARED); 3726 } 3727 3728 static int selinux_file_mprotect(struct vm_area_struct *vma, 3729 unsigned long reqprot, 3730 unsigned long prot) 3731 { 3732 const struct cred *cred = current_cred(); 3733 u32 sid = cred_sid(cred); 3734 3735 if (selinux_state.checkreqprot) 3736 prot = reqprot; 3737 3738 if (default_noexec && 3739 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3740 int rc = 0; 3741 if (vma->vm_start >= vma->vm_mm->start_brk && 3742 vma->vm_end <= vma->vm_mm->brk) { 3743 rc = avc_has_perm(&selinux_state, 3744 sid, sid, SECCLASS_PROCESS, 3745 PROCESS__EXECHEAP, NULL); 3746 } else if (!vma->vm_file && 3747 ((vma->vm_start <= vma->vm_mm->start_stack && 3748 vma->vm_end >= vma->vm_mm->start_stack) || 3749 vma_is_stack_for_current(vma))) { 3750 rc = avc_has_perm(&selinux_state, 3751 sid, sid, SECCLASS_PROCESS, 3752 PROCESS__EXECSTACK, NULL); 3753 } else if (vma->vm_file && vma->anon_vma) { 3754 /* 3755 * We are making executable a file mapping that has 3756 * had some COW done. Since pages might have been 3757 * written, check ability to execute the possibly 3758 * modified content. This typically should only 3759 * occur for text relocations. 3760 */ 3761 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3762 } 3763 if (rc) 3764 return rc; 3765 } 3766 3767 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3768 } 3769 3770 static int selinux_file_lock(struct file *file, unsigned int cmd) 3771 { 3772 const struct cred *cred = current_cred(); 3773 3774 return file_has_perm(cred, file, FILE__LOCK); 3775 } 3776 3777 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3778 unsigned long arg) 3779 { 3780 const struct cred *cred = current_cred(); 3781 int err = 0; 3782 3783 switch (cmd) { 3784 case F_SETFL: 3785 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3786 err = file_has_perm(cred, file, FILE__WRITE); 3787 break; 3788 } 3789 /* fall through */ 3790 case F_SETOWN: 3791 case F_SETSIG: 3792 case F_GETFL: 3793 case F_GETOWN: 3794 case F_GETSIG: 3795 case F_GETOWNER_UIDS: 3796 /* Just check FD__USE permission */ 3797 err = file_has_perm(cred, file, 0); 3798 break; 3799 case F_GETLK: 3800 case F_SETLK: 3801 case F_SETLKW: 3802 case F_OFD_GETLK: 3803 case F_OFD_SETLK: 3804 case F_OFD_SETLKW: 3805 #if BITS_PER_LONG == 32 3806 case F_GETLK64: 3807 case F_SETLK64: 3808 case F_SETLKW64: 3809 #endif 3810 err = file_has_perm(cred, file, FILE__LOCK); 3811 break; 3812 } 3813 3814 return err; 3815 } 3816 3817 static void selinux_file_set_fowner(struct file *file) 3818 { 3819 struct file_security_struct *fsec; 3820 3821 fsec = selinux_file(file); 3822 fsec->fown_sid = current_sid(); 3823 } 3824 3825 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3826 struct fown_struct *fown, int signum) 3827 { 3828 struct file *file; 3829 u32 sid = task_sid(tsk); 3830 u32 perm; 3831 struct file_security_struct *fsec; 3832 3833 /* struct fown_struct is never outside the context of a struct file */ 3834 file = container_of(fown, struct file, f_owner); 3835 3836 fsec = selinux_file(file); 3837 3838 if (!signum) 3839 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3840 else 3841 perm = signal_to_av(signum); 3842 3843 return avc_has_perm(&selinux_state, 3844 fsec->fown_sid, sid, 3845 SECCLASS_PROCESS, perm, NULL); 3846 } 3847 3848 static int selinux_file_receive(struct file *file) 3849 { 3850 const struct cred *cred = current_cred(); 3851 3852 return file_has_perm(cred, file, file_to_av(file)); 3853 } 3854 3855 static int selinux_file_open(struct file *file) 3856 { 3857 struct file_security_struct *fsec; 3858 struct inode_security_struct *isec; 3859 3860 fsec = selinux_file(file); 3861 isec = inode_security(file_inode(file)); 3862 /* 3863 * Save inode label and policy sequence number 3864 * at open-time so that selinux_file_permission 3865 * can determine whether revalidation is necessary. 3866 * Task label is already saved in the file security 3867 * struct as its SID. 3868 */ 3869 fsec->isid = isec->sid; 3870 fsec->pseqno = avc_policy_seqno(&selinux_state); 3871 /* 3872 * Since the inode label or policy seqno may have changed 3873 * between the selinux_inode_permission check and the saving 3874 * of state above, recheck that access is still permitted. 3875 * Otherwise, access might never be revalidated against the 3876 * new inode label or new policy. 3877 * This check is not redundant - do not remove. 3878 */ 3879 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3880 } 3881 3882 /* task security operations */ 3883 3884 static int selinux_task_alloc(struct task_struct *task, 3885 unsigned long clone_flags) 3886 { 3887 u32 sid = current_sid(); 3888 3889 return avc_has_perm(&selinux_state, 3890 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3891 } 3892 3893 /* 3894 * prepare a new set of credentials for modification 3895 */ 3896 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3897 gfp_t gfp) 3898 { 3899 const struct task_security_struct *old_tsec = selinux_cred(old); 3900 struct task_security_struct *tsec = selinux_cred(new); 3901 3902 *tsec = *old_tsec; 3903 return 0; 3904 } 3905 3906 /* 3907 * transfer the SELinux data to a blank set of creds 3908 */ 3909 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3910 { 3911 const struct task_security_struct *old_tsec = selinux_cred(old); 3912 struct task_security_struct *tsec = selinux_cred(new); 3913 3914 *tsec = *old_tsec; 3915 } 3916 3917 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 3918 { 3919 *secid = cred_sid(c); 3920 } 3921 3922 /* 3923 * set the security data for a kernel service 3924 * - all the creation contexts are set to unlabelled 3925 */ 3926 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3927 { 3928 struct task_security_struct *tsec = selinux_cred(new); 3929 u32 sid = current_sid(); 3930 int ret; 3931 3932 ret = avc_has_perm(&selinux_state, 3933 sid, secid, 3934 SECCLASS_KERNEL_SERVICE, 3935 KERNEL_SERVICE__USE_AS_OVERRIDE, 3936 NULL); 3937 if (ret == 0) { 3938 tsec->sid = secid; 3939 tsec->create_sid = 0; 3940 tsec->keycreate_sid = 0; 3941 tsec->sockcreate_sid = 0; 3942 } 3943 return ret; 3944 } 3945 3946 /* 3947 * set the file creation context in a security record to the same as the 3948 * objective context of the specified inode 3949 */ 3950 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3951 { 3952 struct inode_security_struct *isec = inode_security(inode); 3953 struct task_security_struct *tsec = selinux_cred(new); 3954 u32 sid = current_sid(); 3955 int ret; 3956 3957 ret = avc_has_perm(&selinux_state, 3958 sid, isec->sid, 3959 SECCLASS_KERNEL_SERVICE, 3960 KERNEL_SERVICE__CREATE_FILES_AS, 3961 NULL); 3962 3963 if (ret == 0) 3964 tsec->create_sid = isec->sid; 3965 return ret; 3966 } 3967 3968 static int selinux_kernel_module_request(char *kmod_name) 3969 { 3970 struct common_audit_data ad; 3971 3972 ad.type = LSM_AUDIT_DATA_KMOD; 3973 ad.u.kmod_name = kmod_name; 3974 3975 return avc_has_perm(&selinux_state, 3976 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 3977 SYSTEM__MODULE_REQUEST, &ad); 3978 } 3979 3980 static int selinux_kernel_module_from_file(struct file *file) 3981 { 3982 struct common_audit_data ad; 3983 struct inode_security_struct *isec; 3984 struct file_security_struct *fsec; 3985 u32 sid = current_sid(); 3986 int rc; 3987 3988 /* init_module */ 3989 if (file == NULL) 3990 return avc_has_perm(&selinux_state, 3991 sid, sid, SECCLASS_SYSTEM, 3992 SYSTEM__MODULE_LOAD, NULL); 3993 3994 /* finit_module */ 3995 3996 ad.type = LSM_AUDIT_DATA_FILE; 3997 ad.u.file = file; 3998 3999 fsec = selinux_file(file); 4000 if (sid != fsec->sid) { 4001 rc = avc_has_perm(&selinux_state, 4002 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4003 if (rc) 4004 return rc; 4005 } 4006 4007 isec = inode_security(file_inode(file)); 4008 return avc_has_perm(&selinux_state, 4009 sid, isec->sid, SECCLASS_SYSTEM, 4010 SYSTEM__MODULE_LOAD, &ad); 4011 } 4012 4013 static int selinux_kernel_read_file(struct file *file, 4014 enum kernel_read_file_id id) 4015 { 4016 int rc = 0; 4017 4018 switch (id) { 4019 case READING_MODULE: 4020 rc = selinux_kernel_module_from_file(file); 4021 break; 4022 default: 4023 break; 4024 } 4025 4026 return rc; 4027 } 4028 4029 static int selinux_kernel_load_data(enum kernel_load_data_id id) 4030 { 4031 int rc = 0; 4032 4033 switch (id) { 4034 case LOADING_MODULE: 4035 rc = selinux_kernel_module_from_file(NULL); 4036 default: 4037 break; 4038 } 4039 4040 return rc; 4041 } 4042 4043 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4044 { 4045 return avc_has_perm(&selinux_state, 4046 current_sid(), task_sid(p), SECCLASS_PROCESS, 4047 PROCESS__SETPGID, NULL); 4048 } 4049 4050 static int selinux_task_getpgid(struct task_struct *p) 4051 { 4052 return avc_has_perm(&selinux_state, 4053 current_sid(), task_sid(p), SECCLASS_PROCESS, 4054 PROCESS__GETPGID, NULL); 4055 } 4056 4057 static int selinux_task_getsid(struct task_struct *p) 4058 { 4059 return avc_has_perm(&selinux_state, 4060 current_sid(), task_sid(p), SECCLASS_PROCESS, 4061 PROCESS__GETSESSION, NULL); 4062 } 4063 4064 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 4065 { 4066 *secid = task_sid(p); 4067 } 4068 4069 static int selinux_task_setnice(struct task_struct *p, int nice) 4070 { 4071 return avc_has_perm(&selinux_state, 4072 current_sid(), task_sid(p), SECCLASS_PROCESS, 4073 PROCESS__SETSCHED, NULL); 4074 } 4075 4076 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4077 { 4078 return avc_has_perm(&selinux_state, 4079 current_sid(), task_sid(p), SECCLASS_PROCESS, 4080 PROCESS__SETSCHED, NULL); 4081 } 4082 4083 static int selinux_task_getioprio(struct task_struct *p) 4084 { 4085 return avc_has_perm(&selinux_state, 4086 current_sid(), task_sid(p), SECCLASS_PROCESS, 4087 PROCESS__GETSCHED, NULL); 4088 } 4089 4090 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4091 unsigned int flags) 4092 { 4093 u32 av = 0; 4094 4095 if (!flags) 4096 return 0; 4097 if (flags & LSM_PRLIMIT_WRITE) 4098 av |= PROCESS__SETRLIMIT; 4099 if (flags & LSM_PRLIMIT_READ) 4100 av |= PROCESS__GETRLIMIT; 4101 return avc_has_perm(&selinux_state, 4102 cred_sid(cred), cred_sid(tcred), 4103 SECCLASS_PROCESS, av, NULL); 4104 } 4105 4106 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4107 struct rlimit *new_rlim) 4108 { 4109 struct rlimit *old_rlim = p->signal->rlim + resource; 4110 4111 /* Control the ability to change the hard limit (whether 4112 lowering or raising it), so that the hard limit can 4113 later be used as a safe reset point for the soft limit 4114 upon context transitions. See selinux_bprm_committing_creds. */ 4115 if (old_rlim->rlim_max != new_rlim->rlim_max) 4116 return avc_has_perm(&selinux_state, 4117 current_sid(), task_sid(p), 4118 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4119 4120 return 0; 4121 } 4122 4123 static int selinux_task_setscheduler(struct task_struct *p) 4124 { 4125 return avc_has_perm(&selinux_state, 4126 current_sid(), task_sid(p), SECCLASS_PROCESS, 4127 PROCESS__SETSCHED, NULL); 4128 } 4129 4130 static int selinux_task_getscheduler(struct task_struct *p) 4131 { 4132 return avc_has_perm(&selinux_state, 4133 current_sid(), task_sid(p), SECCLASS_PROCESS, 4134 PROCESS__GETSCHED, NULL); 4135 } 4136 4137 static int selinux_task_movememory(struct task_struct *p) 4138 { 4139 return avc_has_perm(&selinux_state, 4140 current_sid(), task_sid(p), SECCLASS_PROCESS, 4141 PROCESS__SETSCHED, NULL); 4142 } 4143 4144 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4145 int sig, const struct cred *cred) 4146 { 4147 u32 secid; 4148 u32 perm; 4149 4150 if (!sig) 4151 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4152 else 4153 perm = signal_to_av(sig); 4154 if (!cred) 4155 secid = current_sid(); 4156 else 4157 secid = cred_sid(cred); 4158 return avc_has_perm(&selinux_state, 4159 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL); 4160 } 4161 4162 static void selinux_task_to_inode(struct task_struct *p, 4163 struct inode *inode) 4164 { 4165 struct inode_security_struct *isec = selinux_inode(inode); 4166 u32 sid = task_sid(p); 4167 4168 spin_lock(&isec->lock); 4169 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4170 isec->sid = sid; 4171 isec->initialized = LABEL_INITIALIZED; 4172 spin_unlock(&isec->lock); 4173 } 4174 4175 /* Returns error only if unable to parse addresses */ 4176 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4177 struct common_audit_data *ad, u8 *proto) 4178 { 4179 int offset, ihlen, ret = -EINVAL; 4180 struct iphdr _iph, *ih; 4181 4182 offset = skb_network_offset(skb); 4183 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4184 if (ih == NULL) 4185 goto out; 4186 4187 ihlen = ih->ihl * 4; 4188 if (ihlen < sizeof(_iph)) 4189 goto out; 4190 4191 ad->u.net->v4info.saddr = ih->saddr; 4192 ad->u.net->v4info.daddr = ih->daddr; 4193 ret = 0; 4194 4195 if (proto) 4196 *proto = ih->protocol; 4197 4198 switch (ih->protocol) { 4199 case IPPROTO_TCP: { 4200 struct tcphdr _tcph, *th; 4201 4202 if (ntohs(ih->frag_off) & IP_OFFSET) 4203 break; 4204 4205 offset += ihlen; 4206 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4207 if (th == NULL) 4208 break; 4209 4210 ad->u.net->sport = th->source; 4211 ad->u.net->dport = th->dest; 4212 break; 4213 } 4214 4215 case IPPROTO_UDP: { 4216 struct udphdr _udph, *uh; 4217 4218 if (ntohs(ih->frag_off) & IP_OFFSET) 4219 break; 4220 4221 offset += ihlen; 4222 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4223 if (uh == NULL) 4224 break; 4225 4226 ad->u.net->sport = uh->source; 4227 ad->u.net->dport = uh->dest; 4228 break; 4229 } 4230 4231 case IPPROTO_DCCP: { 4232 struct dccp_hdr _dccph, *dh; 4233 4234 if (ntohs(ih->frag_off) & IP_OFFSET) 4235 break; 4236 4237 offset += ihlen; 4238 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4239 if (dh == NULL) 4240 break; 4241 4242 ad->u.net->sport = dh->dccph_sport; 4243 ad->u.net->dport = dh->dccph_dport; 4244 break; 4245 } 4246 4247 #if IS_ENABLED(CONFIG_IP_SCTP) 4248 case IPPROTO_SCTP: { 4249 struct sctphdr _sctph, *sh; 4250 4251 if (ntohs(ih->frag_off) & IP_OFFSET) 4252 break; 4253 4254 offset += ihlen; 4255 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4256 if (sh == NULL) 4257 break; 4258 4259 ad->u.net->sport = sh->source; 4260 ad->u.net->dport = sh->dest; 4261 break; 4262 } 4263 #endif 4264 default: 4265 break; 4266 } 4267 out: 4268 return ret; 4269 } 4270 4271 #if IS_ENABLED(CONFIG_IPV6) 4272 4273 /* Returns error only if unable to parse addresses */ 4274 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4275 struct common_audit_data *ad, u8 *proto) 4276 { 4277 u8 nexthdr; 4278 int ret = -EINVAL, offset; 4279 struct ipv6hdr _ipv6h, *ip6; 4280 __be16 frag_off; 4281 4282 offset = skb_network_offset(skb); 4283 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4284 if (ip6 == NULL) 4285 goto out; 4286 4287 ad->u.net->v6info.saddr = ip6->saddr; 4288 ad->u.net->v6info.daddr = ip6->daddr; 4289 ret = 0; 4290 4291 nexthdr = ip6->nexthdr; 4292 offset += sizeof(_ipv6h); 4293 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4294 if (offset < 0) 4295 goto out; 4296 4297 if (proto) 4298 *proto = nexthdr; 4299 4300 switch (nexthdr) { 4301 case IPPROTO_TCP: { 4302 struct tcphdr _tcph, *th; 4303 4304 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4305 if (th == NULL) 4306 break; 4307 4308 ad->u.net->sport = th->source; 4309 ad->u.net->dport = th->dest; 4310 break; 4311 } 4312 4313 case IPPROTO_UDP: { 4314 struct udphdr _udph, *uh; 4315 4316 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4317 if (uh == NULL) 4318 break; 4319 4320 ad->u.net->sport = uh->source; 4321 ad->u.net->dport = uh->dest; 4322 break; 4323 } 4324 4325 case IPPROTO_DCCP: { 4326 struct dccp_hdr _dccph, *dh; 4327 4328 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4329 if (dh == NULL) 4330 break; 4331 4332 ad->u.net->sport = dh->dccph_sport; 4333 ad->u.net->dport = dh->dccph_dport; 4334 break; 4335 } 4336 4337 #if IS_ENABLED(CONFIG_IP_SCTP) 4338 case IPPROTO_SCTP: { 4339 struct sctphdr _sctph, *sh; 4340 4341 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4342 if (sh == NULL) 4343 break; 4344 4345 ad->u.net->sport = sh->source; 4346 ad->u.net->dport = sh->dest; 4347 break; 4348 } 4349 #endif 4350 /* includes fragments */ 4351 default: 4352 break; 4353 } 4354 out: 4355 return ret; 4356 } 4357 4358 #endif /* IPV6 */ 4359 4360 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4361 char **_addrp, int src, u8 *proto) 4362 { 4363 char *addrp; 4364 int ret; 4365 4366 switch (ad->u.net->family) { 4367 case PF_INET: 4368 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4369 if (ret) 4370 goto parse_error; 4371 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4372 &ad->u.net->v4info.daddr); 4373 goto okay; 4374 4375 #if IS_ENABLED(CONFIG_IPV6) 4376 case PF_INET6: 4377 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4378 if (ret) 4379 goto parse_error; 4380 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4381 &ad->u.net->v6info.daddr); 4382 goto okay; 4383 #endif /* IPV6 */ 4384 default: 4385 addrp = NULL; 4386 goto okay; 4387 } 4388 4389 parse_error: 4390 pr_warn( 4391 "SELinux: failure in selinux_parse_skb()," 4392 " unable to parse packet\n"); 4393 return ret; 4394 4395 okay: 4396 if (_addrp) 4397 *_addrp = addrp; 4398 return 0; 4399 } 4400 4401 /** 4402 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4403 * @skb: the packet 4404 * @family: protocol family 4405 * @sid: the packet's peer label SID 4406 * 4407 * Description: 4408 * Check the various different forms of network peer labeling and determine 4409 * the peer label/SID for the packet; most of the magic actually occurs in 4410 * the security server function security_net_peersid_cmp(). The function 4411 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4412 * or -EACCES if @sid is invalid due to inconsistencies with the different 4413 * peer labels. 4414 * 4415 */ 4416 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4417 { 4418 int err; 4419 u32 xfrm_sid; 4420 u32 nlbl_sid; 4421 u32 nlbl_type; 4422 4423 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4424 if (unlikely(err)) 4425 return -EACCES; 4426 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4427 if (unlikely(err)) 4428 return -EACCES; 4429 4430 err = security_net_peersid_resolve(&selinux_state, nlbl_sid, 4431 nlbl_type, xfrm_sid, sid); 4432 if (unlikely(err)) { 4433 pr_warn( 4434 "SELinux: failure in selinux_skb_peerlbl_sid()," 4435 " unable to determine packet's peer label\n"); 4436 return -EACCES; 4437 } 4438 4439 return 0; 4440 } 4441 4442 /** 4443 * selinux_conn_sid - Determine the child socket label for a connection 4444 * @sk_sid: the parent socket's SID 4445 * @skb_sid: the packet's SID 4446 * @conn_sid: the resulting connection SID 4447 * 4448 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4449 * combined with the MLS information from @skb_sid in order to create 4450 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4451 * of @sk_sid. Returns zero on success, negative values on failure. 4452 * 4453 */ 4454 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4455 { 4456 int err = 0; 4457 4458 if (skb_sid != SECSID_NULL) 4459 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid, 4460 conn_sid); 4461 else 4462 *conn_sid = sk_sid; 4463 4464 return err; 4465 } 4466 4467 /* socket security operations */ 4468 4469 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4470 u16 secclass, u32 *socksid) 4471 { 4472 if (tsec->sockcreate_sid > SECSID_NULL) { 4473 *socksid = tsec->sockcreate_sid; 4474 return 0; 4475 } 4476 4477 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid, 4478 secclass, NULL, socksid); 4479 } 4480 4481 static int sock_has_perm(struct sock *sk, u32 perms) 4482 { 4483 struct sk_security_struct *sksec = sk->sk_security; 4484 struct common_audit_data ad; 4485 struct lsm_network_audit net = {0,}; 4486 4487 if (sksec->sid == SECINITSID_KERNEL) 4488 return 0; 4489 4490 ad.type = LSM_AUDIT_DATA_NET; 4491 ad.u.net = &net; 4492 ad.u.net->sk = sk; 4493 4494 return avc_has_perm(&selinux_state, 4495 current_sid(), sksec->sid, sksec->sclass, perms, 4496 &ad); 4497 } 4498 4499 static int selinux_socket_create(int family, int type, 4500 int protocol, int kern) 4501 { 4502 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4503 u32 newsid; 4504 u16 secclass; 4505 int rc; 4506 4507 if (kern) 4508 return 0; 4509 4510 secclass = socket_type_to_security_class(family, type, protocol); 4511 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4512 if (rc) 4513 return rc; 4514 4515 return avc_has_perm(&selinux_state, 4516 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4517 } 4518 4519 static int selinux_socket_post_create(struct socket *sock, int family, 4520 int type, int protocol, int kern) 4521 { 4522 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4523 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4524 struct sk_security_struct *sksec; 4525 u16 sclass = socket_type_to_security_class(family, type, protocol); 4526 u32 sid = SECINITSID_KERNEL; 4527 int err = 0; 4528 4529 if (!kern) { 4530 err = socket_sockcreate_sid(tsec, sclass, &sid); 4531 if (err) 4532 return err; 4533 } 4534 4535 isec->sclass = sclass; 4536 isec->sid = sid; 4537 isec->initialized = LABEL_INITIALIZED; 4538 4539 if (sock->sk) { 4540 sksec = sock->sk->sk_security; 4541 sksec->sclass = sclass; 4542 sksec->sid = sid; 4543 /* Allows detection of the first association on this socket */ 4544 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4545 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4546 4547 err = selinux_netlbl_socket_post_create(sock->sk, family); 4548 } 4549 4550 return err; 4551 } 4552 4553 static int selinux_socket_socketpair(struct socket *socka, 4554 struct socket *sockb) 4555 { 4556 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4557 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4558 4559 sksec_a->peer_sid = sksec_b->sid; 4560 sksec_b->peer_sid = sksec_a->sid; 4561 4562 return 0; 4563 } 4564 4565 /* Range of port numbers used to automatically bind. 4566 Need to determine whether we should perform a name_bind 4567 permission check between the socket and the port number. */ 4568 4569 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4570 { 4571 struct sock *sk = sock->sk; 4572 struct sk_security_struct *sksec = sk->sk_security; 4573 u16 family; 4574 int err; 4575 4576 err = sock_has_perm(sk, SOCKET__BIND); 4577 if (err) 4578 goto out; 4579 4580 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4581 family = sk->sk_family; 4582 if (family == PF_INET || family == PF_INET6) { 4583 char *addrp; 4584 struct common_audit_data ad; 4585 struct lsm_network_audit net = {0,}; 4586 struct sockaddr_in *addr4 = NULL; 4587 struct sockaddr_in6 *addr6 = NULL; 4588 u16 family_sa; 4589 unsigned short snum; 4590 u32 sid, node_perm; 4591 4592 /* 4593 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4594 * that validates multiple binding addresses. Because of this 4595 * need to check address->sa_family as it is possible to have 4596 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4597 */ 4598 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4599 return -EINVAL; 4600 family_sa = address->sa_family; 4601 switch (family_sa) { 4602 case AF_UNSPEC: 4603 case AF_INET: 4604 if (addrlen < sizeof(struct sockaddr_in)) 4605 return -EINVAL; 4606 addr4 = (struct sockaddr_in *)address; 4607 if (family_sa == AF_UNSPEC) { 4608 /* see __inet_bind(), we only want to allow 4609 * AF_UNSPEC if the address is INADDR_ANY 4610 */ 4611 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4612 goto err_af; 4613 family_sa = AF_INET; 4614 } 4615 snum = ntohs(addr4->sin_port); 4616 addrp = (char *)&addr4->sin_addr.s_addr; 4617 break; 4618 case AF_INET6: 4619 if (addrlen < SIN6_LEN_RFC2133) 4620 return -EINVAL; 4621 addr6 = (struct sockaddr_in6 *)address; 4622 snum = ntohs(addr6->sin6_port); 4623 addrp = (char *)&addr6->sin6_addr.s6_addr; 4624 break; 4625 default: 4626 goto err_af; 4627 } 4628 4629 ad.type = LSM_AUDIT_DATA_NET; 4630 ad.u.net = &net; 4631 ad.u.net->sport = htons(snum); 4632 ad.u.net->family = family_sa; 4633 4634 if (snum) { 4635 int low, high; 4636 4637 inet_get_local_port_range(sock_net(sk), &low, &high); 4638 4639 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4640 snum < low || snum > high) { 4641 err = sel_netport_sid(sk->sk_protocol, 4642 snum, &sid); 4643 if (err) 4644 goto out; 4645 err = avc_has_perm(&selinux_state, 4646 sksec->sid, sid, 4647 sksec->sclass, 4648 SOCKET__NAME_BIND, &ad); 4649 if (err) 4650 goto out; 4651 } 4652 } 4653 4654 switch (sksec->sclass) { 4655 case SECCLASS_TCP_SOCKET: 4656 node_perm = TCP_SOCKET__NODE_BIND; 4657 break; 4658 4659 case SECCLASS_UDP_SOCKET: 4660 node_perm = UDP_SOCKET__NODE_BIND; 4661 break; 4662 4663 case SECCLASS_DCCP_SOCKET: 4664 node_perm = DCCP_SOCKET__NODE_BIND; 4665 break; 4666 4667 case SECCLASS_SCTP_SOCKET: 4668 node_perm = SCTP_SOCKET__NODE_BIND; 4669 break; 4670 4671 default: 4672 node_perm = RAWIP_SOCKET__NODE_BIND; 4673 break; 4674 } 4675 4676 err = sel_netnode_sid(addrp, family_sa, &sid); 4677 if (err) 4678 goto out; 4679 4680 if (family_sa == AF_INET) 4681 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4682 else 4683 ad.u.net->v6info.saddr = addr6->sin6_addr; 4684 4685 err = avc_has_perm(&selinux_state, 4686 sksec->sid, sid, 4687 sksec->sclass, node_perm, &ad); 4688 if (err) 4689 goto out; 4690 } 4691 out: 4692 return err; 4693 err_af: 4694 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4695 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4696 return -EINVAL; 4697 return -EAFNOSUPPORT; 4698 } 4699 4700 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4701 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4702 */ 4703 static int selinux_socket_connect_helper(struct socket *sock, 4704 struct sockaddr *address, int addrlen) 4705 { 4706 struct sock *sk = sock->sk; 4707 struct sk_security_struct *sksec = sk->sk_security; 4708 int err; 4709 4710 err = sock_has_perm(sk, SOCKET__CONNECT); 4711 if (err) 4712 return err; 4713 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4714 return -EINVAL; 4715 4716 /* connect(AF_UNSPEC) has special handling, as it is a documented 4717 * way to disconnect the socket 4718 */ 4719 if (address->sa_family == AF_UNSPEC) 4720 return 0; 4721 4722 /* 4723 * If a TCP, DCCP or SCTP socket, check name_connect permission 4724 * for the port. 4725 */ 4726 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4727 sksec->sclass == SECCLASS_DCCP_SOCKET || 4728 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4729 struct common_audit_data ad; 4730 struct lsm_network_audit net = {0,}; 4731 struct sockaddr_in *addr4 = NULL; 4732 struct sockaddr_in6 *addr6 = NULL; 4733 unsigned short snum; 4734 u32 sid, perm; 4735 4736 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4737 * that validates multiple connect addresses. Because of this 4738 * need to check address->sa_family as it is possible to have 4739 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4740 */ 4741 switch (address->sa_family) { 4742 case AF_INET: 4743 addr4 = (struct sockaddr_in *)address; 4744 if (addrlen < sizeof(struct sockaddr_in)) 4745 return -EINVAL; 4746 snum = ntohs(addr4->sin_port); 4747 break; 4748 case AF_INET6: 4749 addr6 = (struct sockaddr_in6 *)address; 4750 if (addrlen < SIN6_LEN_RFC2133) 4751 return -EINVAL; 4752 snum = ntohs(addr6->sin6_port); 4753 break; 4754 default: 4755 /* Note that SCTP services expect -EINVAL, whereas 4756 * others expect -EAFNOSUPPORT. 4757 */ 4758 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4759 return -EINVAL; 4760 else 4761 return -EAFNOSUPPORT; 4762 } 4763 4764 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4765 if (err) 4766 return err; 4767 4768 switch (sksec->sclass) { 4769 case SECCLASS_TCP_SOCKET: 4770 perm = TCP_SOCKET__NAME_CONNECT; 4771 break; 4772 case SECCLASS_DCCP_SOCKET: 4773 perm = DCCP_SOCKET__NAME_CONNECT; 4774 break; 4775 case SECCLASS_SCTP_SOCKET: 4776 perm = SCTP_SOCKET__NAME_CONNECT; 4777 break; 4778 } 4779 4780 ad.type = LSM_AUDIT_DATA_NET; 4781 ad.u.net = &net; 4782 ad.u.net->dport = htons(snum); 4783 ad.u.net->family = address->sa_family; 4784 err = avc_has_perm(&selinux_state, 4785 sksec->sid, sid, sksec->sclass, perm, &ad); 4786 if (err) 4787 return err; 4788 } 4789 4790 return 0; 4791 } 4792 4793 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4794 static int selinux_socket_connect(struct socket *sock, 4795 struct sockaddr *address, int addrlen) 4796 { 4797 int err; 4798 struct sock *sk = sock->sk; 4799 4800 err = selinux_socket_connect_helper(sock, address, addrlen); 4801 if (err) 4802 return err; 4803 4804 return selinux_netlbl_socket_connect(sk, address); 4805 } 4806 4807 static int selinux_socket_listen(struct socket *sock, int backlog) 4808 { 4809 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4810 } 4811 4812 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4813 { 4814 int err; 4815 struct inode_security_struct *isec; 4816 struct inode_security_struct *newisec; 4817 u16 sclass; 4818 u32 sid; 4819 4820 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4821 if (err) 4822 return err; 4823 4824 isec = inode_security_novalidate(SOCK_INODE(sock)); 4825 spin_lock(&isec->lock); 4826 sclass = isec->sclass; 4827 sid = isec->sid; 4828 spin_unlock(&isec->lock); 4829 4830 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4831 newisec->sclass = sclass; 4832 newisec->sid = sid; 4833 newisec->initialized = LABEL_INITIALIZED; 4834 4835 return 0; 4836 } 4837 4838 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4839 int size) 4840 { 4841 return sock_has_perm(sock->sk, SOCKET__WRITE); 4842 } 4843 4844 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4845 int size, int flags) 4846 { 4847 return sock_has_perm(sock->sk, SOCKET__READ); 4848 } 4849 4850 static int selinux_socket_getsockname(struct socket *sock) 4851 { 4852 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4853 } 4854 4855 static int selinux_socket_getpeername(struct socket *sock) 4856 { 4857 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4858 } 4859 4860 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4861 { 4862 int err; 4863 4864 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4865 if (err) 4866 return err; 4867 4868 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4869 } 4870 4871 static int selinux_socket_getsockopt(struct socket *sock, int level, 4872 int optname) 4873 { 4874 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4875 } 4876 4877 static int selinux_socket_shutdown(struct socket *sock, int how) 4878 { 4879 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4880 } 4881 4882 static int selinux_socket_unix_stream_connect(struct sock *sock, 4883 struct sock *other, 4884 struct sock *newsk) 4885 { 4886 struct sk_security_struct *sksec_sock = sock->sk_security; 4887 struct sk_security_struct *sksec_other = other->sk_security; 4888 struct sk_security_struct *sksec_new = newsk->sk_security; 4889 struct common_audit_data ad; 4890 struct lsm_network_audit net = {0,}; 4891 int err; 4892 4893 ad.type = LSM_AUDIT_DATA_NET; 4894 ad.u.net = &net; 4895 ad.u.net->sk = other; 4896 4897 err = avc_has_perm(&selinux_state, 4898 sksec_sock->sid, sksec_other->sid, 4899 sksec_other->sclass, 4900 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4901 if (err) 4902 return err; 4903 4904 /* server child socket */ 4905 sksec_new->peer_sid = sksec_sock->sid; 4906 err = security_sid_mls_copy(&selinux_state, sksec_other->sid, 4907 sksec_sock->sid, &sksec_new->sid); 4908 if (err) 4909 return err; 4910 4911 /* connecting socket */ 4912 sksec_sock->peer_sid = sksec_new->sid; 4913 4914 return 0; 4915 } 4916 4917 static int selinux_socket_unix_may_send(struct socket *sock, 4918 struct socket *other) 4919 { 4920 struct sk_security_struct *ssec = sock->sk->sk_security; 4921 struct sk_security_struct *osec = other->sk->sk_security; 4922 struct common_audit_data ad; 4923 struct lsm_network_audit net = {0,}; 4924 4925 ad.type = LSM_AUDIT_DATA_NET; 4926 ad.u.net = &net; 4927 ad.u.net->sk = other->sk; 4928 4929 return avc_has_perm(&selinux_state, 4930 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4931 &ad); 4932 } 4933 4934 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4935 char *addrp, u16 family, u32 peer_sid, 4936 struct common_audit_data *ad) 4937 { 4938 int err; 4939 u32 if_sid; 4940 u32 node_sid; 4941 4942 err = sel_netif_sid(ns, ifindex, &if_sid); 4943 if (err) 4944 return err; 4945 err = avc_has_perm(&selinux_state, 4946 peer_sid, if_sid, 4947 SECCLASS_NETIF, NETIF__INGRESS, ad); 4948 if (err) 4949 return err; 4950 4951 err = sel_netnode_sid(addrp, family, &node_sid); 4952 if (err) 4953 return err; 4954 return avc_has_perm(&selinux_state, 4955 peer_sid, node_sid, 4956 SECCLASS_NODE, NODE__RECVFROM, ad); 4957 } 4958 4959 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4960 u16 family) 4961 { 4962 int err = 0; 4963 struct sk_security_struct *sksec = sk->sk_security; 4964 u32 sk_sid = sksec->sid; 4965 struct common_audit_data ad; 4966 struct lsm_network_audit net = {0,}; 4967 char *addrp; 4968 4969 ad.type = LSM_AUDIT_DATA_NET; 4970 ad.u.net = &net; 4971 ad.u.net->netif = skb->skb_iif; 4972 ad.u.net->family = family; 4973 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4974 if (err) 4975 return err; 4976 4977 if (selinux_secmark_enabled()) { 4978 err = avc_has_perm(&selinux_state, 4979 sk_sid, skb->secmark, SECCLASS_PACKET, 4980 PACKET__RECV, &ad); 4981 if (err) 4982 return err; 4983 } 4984 4985 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4986 if (err) 4987 return err; 4988 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4989 4990 return err; 4991 } 4992 4993 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4994 { 4995 int err; 4996 struct sk_security_struct *sksec = sk->sk_security; 4997 u16 family = sk->sk_family; 4998 u32 sk_sid = sksec->sid; 4999 struct common_audit_data ad; 5000 struct lsm_network_audit net = {0,}; 5001 char *addrp; 5002 u8 secmark_active; 5003 u8 peerlbl_active; 5004 5005 if (family != PF_INET && family != PF_INET6) 5006 return 0; 5007 5008 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5009 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5010 family = PF_INET; 5011 5012 /* If any sort of compatibility mode is enabled then handoff processing 5013 * to the selinux_sock_rcv_skb_compat() function to deal with the 5014 * special handling. We do this in an attempt to keep this function 5015 * as fast and as clean as possible. */ 5016 if (!selinux_policycap_netpeer()) 5017 return selinux_sock_rcv_skb_compat(sk, skb, family); 5018 5019 secmark_active = selinux_secmark_enabled(); 5020 peerlbl_active = selinux_peerlbl_enabled(); 5021 if (!secmark_active && !peerlbl_active) 5022 return 0; 5023 5024 ad.type = LSM_AUDIT_DATA_NET; 5025 ad.u.net = &net; 5026 ad.u.net->netif = skb->skb_iif; 5027 ad.u.net->family = family; 5028 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5029 if (err) 5030 return err; 5031 5032 if (peerlbl_active) { 5033 u32 peer_sid; 5034 5035 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5036 if (err) 5037 return err; 5038 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5039 addrp, family, peer_sid, &ad); 5040 if (err) { 5041 selinux_netlbl_err(skb, family, err, 0); 5042 return err; 5043 } 5044 err = avc_has_perm(&selinux_state, 5045 sk_sid, peer_sid, SECCLASS_PEER, 5046 PEER__RECV, &ad); 5047 if (err) { 5048 selinux_netlbl_err(skb, family, err, 0); 5049 return err; 5050 } 5051 } 5052 5053 if (secmark_active) { 5054 err = avc_has_perm(&selinux_state, 5055 sk_sid, skb->secmark, SECCLASS_PACKET, 5056 PACKET__RECV, &ad); 5057 if (err) 5058 return err; 5059 } 5060 5061 return err; 5062 } 5063 5064 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 5065 int __user *optlen, unsigned len) 5066 { 5067 int err = 0; 5068 char *scontext; 5069 u32 scontext_len; 5070 struct sk_security_struct *sksec = sock->sk->sk_security; 5071 u32 peer_sid = SECSID_NULL; 5072 5073 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5074 sksec->sclass == SECCLASS_TCP_SOCKET || 5075 sksec->sclass == SECCLASS_SCTP_SOCKET) 5076 peer_sid = sksec->peer_sid; 5077 if (peer_sid == SECSID_NULL) 5078 return -ENOPROTOOPT; 5079 5080 err = security_sid_to_context(&selinux_state, peer_sid, &scontext, 5081 &scontext_len); 5082 if (err) 5083 return err; 5084 5085 if (scontext_len > len) { 5086 err = -ERANGE; 5087 goto out_len; 5088 } 5089 5090 if (copy_to_user(optval, scontext, scontext_len)) 5091 err = -EFAULT; 5092 5093 out_len: 5094 if (put_user(scontext_len, optlen)) 5095 err = -EFAULT; 5096 kfree(scontext); 5097 return err; 5098 } 5099 5100 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5101 { 5102 u32 peer_secid = SECSID_NULL; 5103 u16 family; 5104 struct inode_security_struct *isec; 5105 5106 if (skb && skb->protocol == htons(ETH_P_IP)) 5107 family = PF_INET; 5108 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5109 family = PF_INET6; 5110 else if (sock) 5111 family = sock->sk->sk_family; 5112 else 5113 goto out; 5114 5115 if (sock && family == PF_UNIX) { 5116 isec = inode_security_novalidate(SOCK_INODE(sock)); 5117 peer_secid = isec->sid; 5118 } else if (skb) 5119 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5120 5121 out: 5122 *secid = peer_secid; 5123 if (peer_secid == SECSID_NULL) 5124 return -EINVAL; 5125 return 0; 5126 } 5127 5128 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5129 { 5130 struct sk_security_struct *sksec; 5131 5132 sksec = kzalloc(sizeof(*sksec), priority); 5133 if (!sksec) 5134 return -ENOMEM; 5135 5136 sksec->peer_sid = SECINITSID_UNLABELED; 5137 sksec->sid = SECINITSID_UNLABELED; 5138 sksec->sclass = SECCLASS_SOCKET; 5139 selinux_netlbl_sk_security_reset(sksec); 5140 sk->sk_security = sksec; 5141 5142 return 0; 5143 } 5144 5145 static void selinux_sk_free_security(struct sock *sk) 5146 { 5147 struct sk_security_struct *sksec = sk->sk_security; 5148 5149 sk->sk_security = NULL; 5150 selinux_netlbl_sk_security_free(sksec); 5151 kfree(sksec); 5152 } 5153 5154 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5155 { 5156 struct sk_security_struct *sksec = sk->sk_security; 5157 struct sk_security_struct *newsksec = newsk->sk_security; 5158 5159 newsksec->sid = sksec->sid; 5160 newsksec->peer_sid = sksec->peer_sid; 5161 newsksec->sclass = sksec->sclass; 5162 5163 selinux_netlbl_sk_security_reset(newsksec); 5164 } 5165 5166 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 5167 { 5168 if (!sk) 5169 *secid = SECINITSID_ANY_SOCKET; 5170 else { 5171 struct sk_security_struct *sksec = sk->sk_security; 5172 5173 *secid = sksec->sid; 5174 } 5175 } 5176 5177 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5178 { 5179 struct inode_security_struct *isec = 5180 inode_security_novalidate(SOCK_INODE(parent)); 5181 struct sk_security_struct *sksec = sk->sk_security; 5182 5183 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5184 sk->sk_family == PF_UNIX) 5185 isec->sid = sksec->sid; 5186 sksec->sclass = isec->sclass; 5187 } 5188 5189 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming 5190 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association 5191 * already present). 5192 */ 5193 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep, 5194 struct sk_buff *skb) 5195 { 5196 struct sk_security_struct *sksec = ep->base.sk->sk_security; 5197 struct common_audit_data ad; 5198 struct lsm_network_audit net = {0,}; 5199 u8 peerlbl_active; 5200 u32 peer_sid = SECINITSID_UNLABELED; 5201 u32 conn_sid; 5202 int err = 0; 5203 5204 if (!selinux_policycap_extsockclass()) 5205 return 0; 5206 5207 peerlbl_active = selinux_peerlbl_enabled(); 5208 5209 if (peerlbl_active) { 5210 /* This will return peer_sid = SECSID_NULL if there are 5211 * no peer labels, see security_net_peersid_resolve(). 5212 */ 5213 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family, 5214 &peer_sid); 5215 if (err) 5216 return err; 5217 5218 if (peer_sid == SECSID_NULL) 5219 peer_sid = SECINITSID_UNLABELED; 5220 } 5221 5222 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5223 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5224 5225 /* Here as first association on socket. As the peer SID 5226 * was allowed by peer recv (and the netif/node checks), 5227 * then it is approved by policy and used as the primary 5228 * peer SID for getpeercon(3). 5229 */ 5230 sksec->peer_sid = peer_sid; 5231 } else if (sksec->peer_sid != peer_sid) { 5232 /* Other association peer SIDs are checked to enforce 5233 * consistency among the peer SIDs. 5234 */ 5235 ad.type = LSM_AUDIT_DATA_NET; 5236 ad.u.net = &net; 5237 ad.u.net->sk = ep->base.sk; 5238 err = avc_has_perm(&selinux_state, 5239 sksec->peer_sid, peer_sid, sksec->sclass, 5240 SCTP_SOCKET__ASSOCIATION, &ad); 5241 if (err) 5242 return err; 5243 } 5244 5245 /* Compute the MLS component for the connection and store 5246 * the information in ep. This will be used by SCTP TCP type 5247 * sockets and peeled off connections as they cause a new 5248 * socket to be generated. selinux_sctp_sk_clone() will then 5249 * plug this into the new socket. 5250 */ 5251 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid); 5252 if (err) 5253 return err; 5254 5255 ep->secid = conn_sid; 5256 ep->peer_secid = peer_sid; 5257 5258 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5259 return selinux_netlbl_sctp_assoc_request(ep, skb); 5260 } 5261 5262 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5263 * based on their @optname. 5264 */ 5265 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5266 struct sockaddr *address, 5267 int addrlen) 5268 { 5269 int len, err = 0, walk_size = 0; 5270 void *addr_buf; 5271 struct sockaddr *addr; 5272 struct socket *sock; 5273 5274 if (!selinux_policycap_extsockclass()) 5275 return 0; 5276 5277 /* Process one or more addresses that may be IPv4 or IPv6 */ 5278 sock = sk->sk_socket; 5279 addr_buf = address; 5280 5281 while (walk_size < addrlen) { 5282 if (walk_size + sizeof(sa_family_t) > addrlen) 5283 return -EINVAL; 5284 5285 addr = addr_buf; 5286 switch (addr->sa_family) { 5287 case AF_UNSPEC: 5288 case AF_INET: 5289 len = sizeof(struct sockaddr_in); 5290 break; 5291 case AF_INET6: 5292 len = sizeof(struct sockaddr_in6); 5293 break; 5294 default: 5295 return -EINVAL; 5296 } 5297 5298 if (walk_size + len > addrlen) 5299 return -EINVAL; 5300 5301 err = -EINVAL; 5302 switch (optname) { 5303 /* Bind checks */ 5304 case SCTP_PRIMARY_ADDR: 5305 case SCTP_SET_PEER_PRIMARY_ADDR: 5306 case SCTP_SOCKOPT_BINDX_ADD: 5307 err = selinux_socket_bind(sock, addr, len); 5308 break; 5309 /* Connect checks */ 5310 case SCTP_SOCKOPT_CONNECTX: 5311 case SCTP_PARAM_SET_PRIMARY: 5312 case SCTP_PARAM_ADD_IP: 5313 case SCTP_SENDMSG_CONNECT: 5314 err = selinux_socket_connect_helper(sock, addr, len); 5315 if (err) 5316 return err; 5317 5318 /* As selinux_sctp_bind_connect() is called by the 5319 * SCTP protocol layer, the socket is already locked, 5320 * therefore selinux_netlbl_socket_connect_locked() 5321 * is called here. The situations handled are: 5322 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5323 * whenever a new IP address is added or when a new 5324 * primary address is selected. 5325 * Note that an SCTP connect(2) call happens before 5326 * the SCTP protocol layer and is handled via 5327 * selinux_socket_connect(). 5328 */ 5329 err = selinux_netlbl_socket_connect_locked(sk, addr); 5330 break; 5331 } 5332 5333 if (err) 5334 return err; 5335 5336 addr_buf += len; 5337 walk_size += len; 5338 } 5339 5340 return 0; 5341 } 5342 5343 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5344 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk, 5345 struct sock *newsk) 5346 { 5347 struct sk_security_struct *sksec = sk->sk_security; 5348 struct sk_security_struct *newsksec = newsk->sk_security; 5349 5350 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5351 * the non-sctp clone version. 5352 */ 5353 if (!selinux_policycap_extsockclass()) 5354 return selinux_sk_clone_security(sk, newsk); 5355 5356 newsksec->sid = ep->secid; 5357 newsksec->peer_sid = ep->peer_secid; 5358 newsksec->sclass = sksec->sclass; 5359 selinux_netlbl_sctp_sk_clone(sk, newsk); 5360 } 5361 5362 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 5363 struct request_sock *req) 5364 { 5365 struct sk_security_struct *sksec = sk->sk_security; 5366 int err; 5367 u16 family = req->rsk_ops->family; 5368 u32 connsid; 5369 u32 peersid; 5370 5371 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5372 if (err) 5373 return err; 5374 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5375 if (err) 5376 return err; 5377 req->secid = connsid; 5378 req->peer_secid = peersid; 5379 5380 return selinux_netlbl_inet_conn_request(req, family); 5381 } 5382 5383 static void selinux_inet_csk_clone(struct sock *newsk, 5384 const struct request_sock *req) 5385 { 5386 struct sk_security_struct *newsksec = newsk->sk_security; 5387 5388 newsksec->sid = req->secid; 5389 newsksec->peer_sid = req->peer_secid; 5390 /* NOTE: Ideally, we should also get the isec->sid for the 5391 new socket in sync, but we don't have the isec available yet. 5392 So we will wait until sock_graft to do it, by which 5393 time it will have been created and available. */ 5394 5395 /* We don't need to take any sort of lock here as we are the only 5396 * thread with access to newsksec */ 5397 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5398 } 5399 5400 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5401 { 5402 u16 family = sk->sk_family; 5403 struct sk_security_struct *sksec = sk->sk_security; 5404 5405 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5406 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5407 family = PF_INET; 5408 5409 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5410 } 5411 5412 static int selinux_secmark_relabel_packet(u32 sid) 5413 { 5414 const struct task_security_struct *__tsec; 5415 u32 tsid; 5416 5417 __tsec = selinux_cred(current_cred()); 5418 tsid = __tsec->sid; 5419 5420 return avc_has_perm(&selinux_state, 5421 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5422 NULL); 5423 } 5424 5425 static void selinux_secmark_refcount_inc(void) 5426 { 5427 atomic_inc(&selinux_secmark_refcount); 5428 } 5429 5430 static void selinux_secmark_refcount_dec(void) 5431 { 5432 atomic_dec(&selinux_secmark_refcount); 5433 } 5434 5435 static void selinux_req_classify_flow(const struct request_sock *req, 5436 struct flowi *fl) 5437 { 5438 fl->flowi_secid = req->secid; 5439 } 5440 5441 static int selinux_tun_dev_alloc_security(void **security) 5442 { 5443 struct tun_security_struct *tunsec; 5444 5445 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5446 if (!tunsec) 5447 return -ENOMEM; 5448 tunsec->sid = current_sid(); 5449 5450 *security = tunsec; 5451 return 0; 5452 } 5453 5454 static void selinux_tun_dev_free_security(void *security) 5455 { 5456 kfree(security); 5457 } 5458 5459 static int selinux_tun_dev_create(void) 5460 { 5461 u32 sid = current_sid(); 5462 5463 /* we aren't taking into account the "sockcreate" SID since the socket 5464 * that is being created here is not a socket in the traditional sense, 5465 * instead it is a private sock, accessible only to the kernel, and 5466 * representing a wide range of network traffic spanning multiple 5467 * connections unlike traditional sockets - check the TUN driver to 5468 * get a better understanding of why this socket is special */ 5469 5470 return avc_has_perm(&selinux_state, 5471 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5472 NULL); 5473 } 5474 5475 static int selinux_tun_dev_attach_queue(void *security) 5476 { 5477 struct tun_security_struct *tunsec = security; 5478 5479 return avc_has_perm(&selinux_state, 5480 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5481 TUN_SOCKET__ATTACH_QUEUE, NULL); 5482 } 5483 5484 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5485 { 5486 struct tun_security_struct *tunsec = security; 5487 struct sk_security_struct *sksec = sk->sk_security; 5488 5489 /* we don't currently perform any NetLabel based labeling here and it 5490 * isn't clear that we would want to do so anyway; while we could apply 5491 * labeling without the support of the TUN user the resulting labeled 5492 * traffic from the other end of the connection would almost certainly 5493 * cause confusion to the TUN user that had no idea network labeling 5494 * protocols were being used */ 5495 5496 sksec->sid = tunsec->sid; 5497 sksec->sclass = SECCLASS_TUN_SOCKET; 5498 5499 return 0; 5500 } 5501 5502 static int selinux_tun_dev_open(void *security) 5503 { 5504 struct tun_security_struct *tunsec = security; 5505 u32 sid = current_sid(); 5506 int err; 5507 5508 err = avc_has_perm(&selinux_state, 5509 sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5510 TUN_SOCKET__RELABELFROM, NULL); 5511 if (err) 5512 return err; 5513 err = avc_has_perm(&selinux_state, 5514 sid, sid, SECCLASS_TUN_SOCKET, 5515 TUN_SOCKET__RELABELTO, NULL); 5516 if (err) 5517 return err; 5518 tunsec->sid = sid; 5519 5520 return 0; 5521 } 5522 5523 #ifdef CONFIG_NETFILTER 5524 5525 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5526 const struct net_device *indev, 5527 u16 family) 5528 { 5529 int err; 5530 char *addrp; 5531 u32 peer_sid; 5532 struct common_audit_data ad; 5533 struct lsm_network_audit net = {0,}; 5534 u8 secmark_active; 5535 u8 netlbl_active; 5536 u8 peerlbl_active; 5537 5538 if (!selinux_policycap_netpeer()) 5539 return NF_ACCEPT; 5540 5541 secmark_active = selinux_secmark_enabled(); 5542 netlbl_active = netlbl_enabled(); 5543 peerlbl_active = selinux_peerlbl_enabled(); 5544 if (!secmark_active && !peerlbl_active) 5545 return NF_ACCEPT; 5546 5547 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5548 return NF_DROP; 5549 5550 ad.type = LSM_AUDIT_DATA_NET; 5551 ad.u.net = &net; 5552 ad.u.net->netif = indev->ifindex; 5553 ad.u.net->family = family; 5554 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5555 return NF_DROP; 5556 5557 if (peerlbl_active) { 5558 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5559 addrp, family, peer_sid, &ad); 5560 if (err) { 5561 selinux_netlbl_err(skb, family, err, 1); 5562 return NF_DROP; 5563 } 5564 } 5565 5566 if (secmark_active) 5567 if (avc_has_perm(&selinux_state, 5568 peer_sid, skb->secmark, 5569 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5570 return NF_DROP; 5571 5572 if (netlbl_active) 5573 /* we do this in the FORWARD path and not the POST_ROUTING 5574 * path because we want to make sure we apply the necessary 5575 * labeling before IPsec is applied so we can leverage AH 5576 * protection */ 5577 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5578 return NF_DROP; 5579 5580 return NF_ACCEPT; 5581 } 5582 5583 static unsigned int selinux_ipv4_forward(void *priv, 5584 struct sk_buff *skb, 5585 const struct nf_hook_state *state) 5586 { 5587 return selinux_ip_forward(skb, state->in, PF_INET); 5588 } 5589 5590 #if IS_ENABLED(CONFIG_IPV6) 5591 static unsigned int selinux_ipv6_forward(void *priv, 5592 struct sk_buff *skb, 5593 const struct nf_hook_state *state) 5594 { 5595 return selinux_ip_forward(skb, state->in, PF_INET6); 5596 } 5597 #endif /* IPV6 */ 5598 5599 static unsigned int selinux_ip_output(struct sk_buff *skb, 5600 u16 family) 5601 { 5602 struct sock *sk; 5603 u32 sid; 5604 5605 if (!netlbl_enabled()) 5606 return NF_ACCEPT; 5607 5608 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5609 * because we want to make sure we apply the necessary labeling 5610 * before IPsec is applied so we can leverage AH protection */ 5611 sk = skb->sk; 5612 if (sk) { 5613 struct sk_security_struct *sksec; 5614 5615 if (sk_listener(sk)) 5616 /* if the socket is the listening state then this 5617 * packet is a SYN-ACK packet which means it needs to 5618 * be labeled based on the connection/request_sock and 5619 * not the parent socket. unfortunately, we can't 5620 * lookup the request_sock yet as it isn't queued on 5621 * the parent socket until after the SYN-ACK is sent. 5622 * the "solution" is to simply pass the packet as-is 5623 * as any IP option based labeling should be copied 5624 * from the initial connection request (in the IP 5625 * layer). it is far from ideal, but until we get a 5626 * security label in the packet itself this is the 5627 * best we can do. */ 5628 return NF_ACCEPT; 5629 5630 /* standard practice, label using the parent socket */ 5631 sksec = sk->sk_security; 5632 sid = sksec->sid; 5633 } else 5634 sid = SECINITSID_KERNEL; 5635 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5636 return NF_DROP; 5637 5638 return NF_ACCEPT; 5639 } 5640 5641 static unsigned int selinux_ipv4_output(void *priv, 5642 struct sk_buff *skb, 5643 const struct nf_hook_state *state) 5644 { 5645 return selinux_ip_output(skb, PF_INET); 5646 } 5647 5648 #if IS_ENABLED(CONFIG_IPV6) 5649 static unsigned int selinux_ipv6_output(void *priv, 5650 struct sk_buff *skb, 5651 const struct nf_hook_state *state) 5652 { 5653 return selinux_ip_output(skb, PF_INET6); 5654 } 5655 #endif /* IPV6 */ 5656 5657 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5658 int ifindex, 5659 u16 family) 5660 { 5661 struct sock *sk = skb_to_full_sk(skb); 5662 struct sk_security_struct *sksec; 5663 struct common_audit_data ad; 5664 struct lsm_network_audit net = {0,}; 5665 char *addrp; 5666 u8 proto; 5667 5668 if (sk == NULL) 5669 return NF_ACCEPT; 5670 sksec = sk->sk_security; 5671 5672 ad.type = LSM_AUDIT_DATA_NET; 5673 ad.u.net = &net; 5674 ad.u.net->netif = ifindex; 5675 ad.u.net->family = family; 5676 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5677 return NF_DROP; 5678 5679 if (selinux_secmark_enabled()) 5680 if (avc_has_perm(&selinux_state, 5681 sksec->sid, skb->secmark, 5682 SECCLASS_PACKET, PACKET__SEND, &ad)) 5683 return NF_DROP_ERR(-ECONNREFUSED); 5684 5685 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5686 return NF_DROP_ERR(-ECONNREFUSED); 5687 5688 return NF_ACCEPT; 5689 } 5690 5691 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5692 const struct net_device *outdev, 5693 u16 family) 5694 { 5695 u32 secmark_perm; 5696 u32 peer_sid; 5697 int ifindex = outdev->ifindex; 5698 struct sock *sk; 5699 struct common_audit_data ad; 5700 struct lsm_network_audit net = {0,}; 5701 char *addrp; 5702 u8 secmark_active; 5703 u8 peerlbl_active; 5704 5705 /* If any sort of compatibility mode is enabled then handoff processing 5706 * to the selinux_ip_postroute_compat() function to deal with the 5707 * special handling. We do this in an attempt to keep this function 5708 * as fast and as clean as possible. */ 5709 if (!selinux_policycap_netpeer()) 5710 return selinux_ip_postroute_compat(skb, ifindex, family); 5711 5712 secmark_active = selinux_secmark_enabled(); 5713 peerlbl_active = selinux_peerlbl_enabled(); 5714 if (!secmark_active && !peerlbl_active) 5715 return NF_ACCEPT; 5716 5717 sk = skb_to_full_sk(skb); 5718 5719 #ifdef CONFIG_XFRM 5720 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5721 * packet transformation so allow the packet to pass without any checks 5722 * since we'll have another chance to perform access control checks 5723 * when the packet is on it's final way out. 5724 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5725 * is NULL, in this case go ahead and apply access control. 5726 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5727 * TCP listening state we cannot wait until the XFRM processing 5728 * is done as we will miss out on the SA label if we do; 5729 * unfortunately, this means more work, but it is only once per 5730 * connection. */ 5731 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5732 !(sk && sk_listener(sk))) 5733 return NF_ACCEPT; 5734 #endif 5735 5736 if (sk == NULL) { 5737 /* Without an associated socket the packet is either coming 5738 * from the kernel or it is being forwarded; check the packet 5739 * to determine which and if the packet is being forwarded 5740 * query the packet directly to determine the security label. */ 5741 if (skb->skb_iif) { 5742 secmark_perm = PACKET__FORWARD_OUT; 5743 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5744 return NF_DROP; 5745 } else { 5746 secmark_perm = PACKET__SEND; 5747 peer_sid = SECINITSID_KERNEL; 5748 } 5749 } else if (sk_listener(sk)) { 5750 /* Locally generated packet but the associated socket is in the 5751 * listening state which means this is a SYN-ACK packet. In 5752 * this particular case the correct security label is assigned 5753 * to the connection/request_sock but unfortunately we can't 5754 * query the request_sock as it isn't queued on the parent 5755 * socket until after the SYN-ACK packet is sent; the only 5756 * viable choice is to regenerate the label like we do in 5757 * selinux_inet_conn_request(). See also selinux_ip_output() 5758 * for similar problems. */ 5759 u32 skb_sid; 5760 struct sk_security_struct *sksec; 5761 5762 sksec = sk->sk_security; 5763 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5764 return NF_DROP; 5765 /* At this point, if the returned skb peerlbl is SECSID_NULL 5766 * and the packet has been through at least one XFRM 5767 * transformation then we must be dealing with the "final" 5768 * form of labeled IPsec packet; since we've already applied 5769 * all of our access controls on this packet we can safely 5770 * pass the packet. */ 5771 if (skb_sid == SECSID_NULL) { 5772 switch (family) { 5773 case PF_INET: 5774 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5775 return NF_ACCEPT; 5776 break; 5777 case PF_INET6: 5778 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5779 return NF_ACCEPT; 5780 break; 5781 default: 5782 return NF_DROP_ERR(-ECONNREFUSED); 5783 } 5784 } 5785 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5786 return NF_DROP; 5787 secmark_perm = PACKET__SEND; 5788 } else { 5789 /* Locally generated packet, fetch the security label from the 5790 * associated socket. */ 5791 struct sk_security_struct *sksec = sk->sk_security; 5792 peer_sid = sksec->sid; 5793 secmark_perm = PACKET__SEND; 5794 } 5795 5796 ad.type = LSM_AUDIT_DATA_NET; 5797 ad.u.net = &net; 5798 ad.u.net->netif = ifindex; 5799 ad.u.net->family = family; 5800 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5801 return NF_DROP; 5802 5803 if (secmark_active) 5804 if (avc_has_perm(&selinux_state, 5805 peer_sid, skb->secmark, 5806 SECCLASS_PACKET, secmark_perm, &ad)) 5807 return NF_DROP_ERR(-ECONNREFUSED); 5808 5809 if (peerlbl_active) { 5810 u32 if_sid; 5811 u32 node_sid; 5812 5813 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5814 return NF_DROP; 5815 if (avc_has_perm(&selinux_state, 5816 peer_sid, if_sid, 5817 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5818 return NF_DROP_ERR(-ECONNREFUSED); 5819 5820 if (sel_netnode_sid(addrp, family, &node_sid)) 5821 return NF_DROP; 5822 if (avc_has_perm(&selinux_state, 5823 peer_sid, node_sid, 5824 SECCLASS_NODE, NODE__SENDTO, &ad)) 5825 return NF_DROP_ERR(-ECONNREFUSED); 5826 } 5827 5828 return NF_ACCEPT; 5829 } 5830 5831 static unsigned int selinux_ipv4_postroute(void *priv, 5832 struct sk_buff *skb, 5833 const struct nf_hook_state *state) 5834 { 5835 return selinux_ip_postroute(skb, state->out, PF_INET); 5836 } 5837 5838 #if IS_ENABLED(CONFIG_IPV6) 5839 static unsigned int selinux_ipv6_postroute(void *priv, 5840 struct sk_buff *skb, 5841 const struct nf_hook_state *state) 5842 { 5843 return selinux_ip_postroute(skb, state->out, PF_INET6); 5844 } 5845 #endif /* IPV6 */ 5846 5847 #endif /* CONFIG_NETFILTER */ 5848 5849 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5850 { 5851 int rc = 0; 5852 unsigned int msg_len; 5853 unsigned int data_len = skb->len; 5854 unsigned char *data = skb->data; 5855 struct nlmsghdr *nlh; 5856 struct sk_security_struct *sksec = sk->sk_security; 5857 u16 sclass = sksec->sclass; 5858 u32 perm; 5859 5860 while (data_len >= nlmsg_total_size(0)) { 5861 nlh = (struct nlmsghdr *)data; 5862 5863 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5864 * users which means we can't reject skb's with bogus 5865 * length fields; our solution is to follow what 5866 * netlink_rcv_skb() does and simply skip processing at 5867 * messages with length fields that are clearly junk 5868 */ 5869 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5870 return 0; 5871 5872 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5873 if (rc == 0) { 5874 rc = sock_has_perm(sk, perm); 5875 if (rc) 5876 return rc; 5877 } else if (rc == -EINVAL) { 5878 /* -EINVAL is a missing msg/perm mapping */ 5879 pr_warn_ratelimited("SELinux: unrecognized netlink" 5880 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5881 " pid=%d comm=%s\n", 5882 sk->sk_protocol, nlh->nlmsg_type, 5883 secclass_map[sclass - 1].name, 5884 task_pid_nr(current), current->comm); 5885 if (enforcing_enabled(&selinux_state) && 5886 !security_get_allow_unknown(&selinux_state)) 5887 return rc; 5888 rc = 0; 5889 } else if (rc == -ENOENT) { 5890 /* -ENOENT is a missing socket/class mapping, ignore */ 5891 rc = 0; 5892 } else { 5893 return rc; 5894 } 5895 5896 /* move to the next message after applying netlink padding */ 5897 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5898 if (msg_len >= data_len) 5899 return 0; 5900 data_len -= msg_len; 5901 data += msg_len; 5902 } 5903 5904 return rc; 5905 } 5906 5907 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5908 { 5909 isec->sclass = sclass; 5910 isec->sid = current_sid(); 5911 } 5912 5913 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5914 u32 perms) 5915 { 5916 struct ipc_security_struct *isec; 5917 struct common_audit_data ad; 5918 u32 sid = current_sid(); 5919 5920 isec = selinux_ipc(ipc_perms); 5921 5922 ad.type = LSM_AUDIT_DATA_IPC; 5923 ad.u.ipc_id = ipc_perms->key; 5924 5925 return avc_has_perm(&selinux_state, 5926 sid, isec->sid, isec->sclass, perms, &ad); 5927 } 5928 5929 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5930 { 5931 struct msg_security_struct *msec; 5932 5933 msec = selinux_msg_msg(msg); 5934 msec->sid = SECINITSID_UNLABELED; 5935 5936 return 0; 5937 } 5938 5939 /* message queue security operations */ 5940 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5941 { 5942 struct ipc_security_struct *isec; 5943 struct common_audit_data ad; 5944 u32 sid = current_sid(); 5945 int rc; 5946 5947 isec = selinux_ipc(msq); 5948 ipc_init_security(isec, SECCLASS_MSGQ); 5949 5950 ad.type = LSM_AUDIT_DATA_IPC; 5951 ad.u.ipc_id = msq->key; 5952 5953 rc = avc_has_perm(&selinux_state, 5954 sid, isec->sid, SECCLASS_MSGQ, 5955 MSGQ__CREATE, &ad); 5956 return rc; 5957 } 5958 5959 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 5960 { 5961 struct ipc_security_struct *isec; 5962 struct common_audit_data ad; 5963 u32 sid = current_sid(); 5964 5965 isec = selinux_ipc(msq); 5966 5967 ad.type = LSM_AUDIT_DATA_IPC; 5968 ad.u.ipc_id = msq->key; 5969 5970 return avc_has_perm(&selinux_state, 5971 sid, isec->sid, SECCLASS_MSGQ, 5972 MSGQ__ASSOCIATE, &ad); 5973 } 5974 5975 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 5976 { 5977 int err; 5978 int perms; 5979 5980 switch (cmd) { 5981 case IPC_INFO: 5982 case MSG_INFO: 5983 /* No specific object, just general system-wide information. */ 5984 return avc_has_perm(&selinux_state, 5985 current_sid(), SECINITSID_KERNEL, 5986 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 5987 case IPC_STAT: 5988 case MSG_STAT: 5989 case MSG_STAT_ANY: 5990 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 5991 break; 5992 case IPC_SET: 5993 perms = MSGQ__SETATTR; 5994 break; 5995 case IPC_RMID: 5996 perms = MSGQ__DESTROY; 5997 break; 5998 default: 5999 return 0; 6000 } 6001 6002 err = ipc_has_perm(msq, perms); 6003 return err; 6004 } 6005 6006 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6007 { 6008 struct ipc_security_struct *isec; 6009 struct msg_security_struct *msec; 6010 struct common_audit_data ad; 6011 u32 sid = current_sid(); 6012 int rc; 6013 6014 isec = selinux_ipc(msq); 6015 msec = selinux_msg_msg(msg); 6016 6017 /* 6018 * First time through, need to assign label to the message 6019 */ 6020 if (msec->sid == SECINITSID_UNLABELED) { 6021 /* 6022 * Compute new sid based on current process and 6023 * message queue this message will be stored in 6024 */ 6025 rc = security_transition_sid(&selinux_state, sid, isec->sid, 6026 SECCLASS_MSG, NULL, &msec->sid); 6027 if (rc) 6028 return rc; 6029 } 6030 6031 ad.type = LSM_AUDIT_DATA_IPC; 6032 ad.u.ipc_id = msq->key; 6033 6034 /* Can this process write to the queue? */ 6035 rc = avc_has_perm(&selinux_state, 6036 sid, isec->sid, SECCLASS_MSGQ, 6037 MSGQ__WRITE, &ad); 6038 if (!rc) 6039 /* Can this process send the message */ 6040 rc = avc_has_perm(&selinux_state, 6041 sid, msec->sid, SECCLASS_MSG, 6042 MSG__SEND, &ad); 6043 if (!rc) 6044 /* Can the message be put in the queue? */ 6045 rc = avc_has_perm(&selinux_state, 6046 msec->sid, isec->sid, SECCLASS_MSGQ, 6047 MSGQ__ENQUEUE, &ad); 6048 6049 return rc; 6050 } 6051 6052 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6053 struct task_struct *target, 6054 long type, int mode) 6055 { 6056 struct ipc_security_struct *isec; 6057 struct msg_security_struct *msec; 6058 struct common_audit_data ad; 6059 u32 sid = task_sid(target); 6060 int rc; 6061 6062 isec = selinux_ipc(msq); 6063 msec = selinux_msg_msg(msg); 6064 6065 ad.type = LSM_AUDIT_DATA_IPC; 6066 ad.u.ipc_id = msq->key; 6067 6068 rc = avc_has_perm(&selinux_state, 6069 sid, isec->sid, 6070 SECCLASS_MSGQ, MSGQ__READ, &ad); 6071 if (!rc) 6072 rc = avc_has_perm(&selinux_state, 6073 sid, msec->sid, 6074 SECCLASS_MSG, MSG__RECEIVE, &ad); 6075 return rc; 6076 } 6077 6078 /* Shared Memory security operations */ 6079 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6080 { 6081 struct ipc_security_struct *isec; 6082 struct common_audit_data ad; 6083 u32 sid = current_sid(); 6084 int rc; 6085 6086 isec = selinux_ipc(shp); 6087 ipc_init_security(isec, SECCLASS_SHM); 6088 6089 ad.type = LSM_AUDIT_DATA_IPC; 6090 ad.u.ipc_id = shp->key; 6091 6092 rc = avc_has_perm(&selinux_state, 6093 sid, isec->sid, SECCLASS_SHM, 6094 SHM__CREATE, &ad); 6095 return rc; 6096 } 6097 6098 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6099 { 6100 struct ipc_security_struct *isec; 6101 struct common_audit_data ad; 6102 u32 sid = current_sid(); 6103 6104 isec = selinux_ipc(shp); 6105 6106 ad.type = LSM_AUDIT_DATA_IPC; 6107 ad.u.ipc_id = shp->key; 6108 6109 return avc_has_perm(&selinux_state, 6110 sid, isec->sid, SECCLASS_SHM, 6111 SHM__ASSOCIATE, &ad); 6112 } 6113 6114 /* Note, at this point, shp is locked down */ 6115 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6116 { 6117 int perms; 6118 int err; 6119 6120 switch (cmd) { 6121 case IPC_INFO: 6122 case SHM_INFO: 6123 /* No specific object, just general system-wide information. */ 6124 return avc_has_perm(&selinux_state, 6125 current_sid(), SECINITSID_KERNEL, 6126 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6127 case IPC_STAT: 6128 case SHM_STAT: 6129 case SHM_STAT_ANY: 6130 perms = SHM__GETATTR | SHM__ASSOCIATE; 6131 break; 6132 case IPC_SET: 6133 perms = SHM__SETATTR; 6134 break; 6135 case SHM_LOCK: 6136 case SHM_UNLOCK: 6137 perms = SHM__LOCK; 6138 break; 6139 case IPC_RMID: 6140 perms = SHM__DESTROY; 6141 break; 6142 default: 6143 return 0; 6144 } 6145 6146 err = ipc_has_perm(shp, perms); 6147 return err; 6148 } 6149 6150 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6151 char __user *shmaddr, int shmflg) 6152 { 6153 u32 perms; 6154 6155 if (shmflg & SHM_RDONLY) 6156 perms = SHM__READ; 6157 else 6158 perms = SHM__READ | SHM__WRITE; 6159 6160 return ipc_has_perm(shp, perms); 6161 } 6162 6163 /* Semaphore security operations */ 6164 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6165 { 6166 struct ipc_security_struct *isec; 6167 struct common_audit_data ad; 6168 u32 sid = current_sid(); 6169 int rc; 6170 6171 isec = selinux_ipc(sma); 6172 ipc_init_security(isec, SECCLASS_SEM); 6173 6174 ad.type = LSM_AUDIT_DATA_IPC; 6175 ad.u.ipc_id = sma->key; 6176 6177 rc = avc_has_perm(&selinux_state, 6178 sid, isec->sid, SECCLASS_SEM, 6179 SEM__CREATE, &ad); 6180 return rc; 6181 } 6182 6183 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6184 { 6185 struct ipc_security_struct *isec; 6186 struct common_audit_data ad; 6187 u32 sid = current_sid(); 6188 6189 isec = selinux_ipc(sma); 6190 6191 ad.type = LSM_AUDIT_DATA_IPC; 6192 ad.u.ipc_id = sma->key; 6193 6194 return avc_has_perm(&selinux_state, 6195 sid, isec->sid, SECCLASS_SEM, 6196 SEM__ASSOCIATE, &ad); 6197 } 6198 6199 /* Note, at this point, sma is locked down */ 6200 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6201 { 6202 int err; 6203 u32 perms; 6204 6205 switch (cmd) { 6206 case IPC_INFO: 6207 case SEM_INFO: 6208 /* No specific object, just general system-wide information. */ 6209 return avc_has_perm(&selinux_state, 6210 current_sid(), SECINITSID_KERNEL, 6211 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6212 case GETPID: 6213 case GETNCNT: 6214 case GETZCNT: 6215 perms = SEM__GETATTR; 6216 break; 6217 case GETVAL: 6218 case GETALL: 6219 perms = SEM__READ; 6220 break; 6221 case SETVAL: 6222 case SETALL: 6223 perms = SEM__WRITE; 6224 break; 6225 case IPC_RMID: 6226 perms = SEM__DESTROY; 6227 break; 6228 case IPC_SET: 6229 perms = SEM__SETATTR; 6230 break; 6231 case IPC_STAT: 6232 case SEM_STAT: 6233 case SEM_STAT_ANY: 6234 perms = SEM__GETATTR | SEM__ASSOCIATE; 6235 break; 6236 default: 6237 return 0; 6238 } 6239 6240 err = ipc_has_perm(sma, perms); 6241 return err; 6242 } 6243 6244 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6245 struct sembuf *sops, unsigned nsops, int alter) 6246 { 6247 u32 perms; 6248 6249 if (alter) 6250 perms = SEM__READ | SEM__WRITE; 6251 else 6252 perms = SEM__READ; 6253 6254 return ipc_has_perm(sma, perms); 6255 } 6256 6257 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6258 { 6259 u32 av = 0; 6260 6261 av = 0; 6262 if (flag & S_IRUGO) 6263 av |= IPC__UNIX_READ; 6264 if (flag & S_IWUGO) 6265 av |= IPC__UNIX_WRITE; 6266 6267 if (av == 0) 6268 return 0; 6269 6270 return ipc_has_perm(ipcp, av); 6271 } 6272 6273 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6274 { 6275 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6276 *secid = isec->sid; 6277 } 6278 6279 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6280 { 6281 if (inode) 6282 inode_doinit_with_dentry(inode, dentry); 6283 } 6284 6285 static int selinux_getprocattr(struct task_struct *p, 6286 char *name, char **value) 6287 { 6288 const struct task_security_struct *__tsec; 6289 u32 sid; 6290 int error; 6291 unsigned len; 6292 6293 rcu_read_lock(); 6294 __tsec = selinux_cred(__task_cred(p)); 6295 6296 if (current != p) { 6297 error = avc_has_perm(&selinux_state, 6298 current_sid(), __tsec->sid, 6299 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6300 if (error) 6301 goto bad; 6302 } 6303 6304 if (!strcmp(name, "current")) 6305 sid = __tsec->sid; 6306 else if (!strcmp(name, "prev")) 6307 sid = __tsec->osid; 6308 else if (!strcmp(name, "exec")) 6309 sid = __tsec->exec_sid; 6310 else if (!strcmp(name, "fscreate")) 6311 sid = __tsec->create_sid; 6312 else if (!strcmp(name, "keycreate")) 6313 sid = __tsec->keycreate_sid; 6314 else if (!strcmp(name, "sockcreate")) 6315 sid = __tsec->sockcreate_sid; 6316 else { 6317 error = -EINVAL; 6318 goto bad; 6319 } 6320 rcu_read_unlock(); 6321 6322 if (!sid) 6323 return 0; 6324 6325 error = security_sid_to_context(&selinux_state, sid, value, &len); 6326 if (error) 6327 return error; 6328 return len; 6329 6330 bad: 6331 rcu_read_unlock(); 6332 return error; 6333 } 6334 6335 static int selinux_setprocattr(const char *name, void *value, size_t size) 6336 { 6337 struct task_security_struct *tsec; 6338 struct cred *new; 6339 u32 mysid = current_sid(), sid = 0, ptsid; 6340 int error; 6341 char *str = value; 6342 6343 /* 6344 * Basic control over ability to set these attributes at all. 6345 */ 6346 if (!strcmp(name, "exec")) 6347 error = avc_has_perm(&selinux_state, 6348 mysid, mysid, SECCLASS_PROCESS, 6349 PROCESS__SETEXEC, NULL); 6350 else if (!strcmp(name, "fscreate")) 6351 error = avc_has_perm(&selinux_state, 6352 mysid, mysid, SECCLASS_PROCESS, 6353 PROCESS__SETFSCREATE, NULL); 6354 else if (!strcmp(name, "keycreate")) 6355 error = avc_has_perm(&selinux_state, 6356 mysid, mysid, SECCLASS_PROCESS, 6357 PROCESS__SETKEYCREATE, NULL); 6358 else if (!strcmp(name, "sockcreate")) 6359 error = avc_has_perm(&selinux_state, 6360 mysid, mysid, SECCLASS_PROCESS, 6361 PROCESS__SETSOCKCREATE, NULL); 6362 else if (!strcmp(name, "current")) 6363 error = avc_has_perm(&selinux_state, 6364 mysid, mysid, SECCLASS_PROCESS, 6365 PROCESS__SETCURRENT, NULL); 6366 else 6367 error = -EINVAL; 6368 if (error) 6369 return error; 6370 6371 /* Obtain a SID for the context, if one was specified. */ 6372 if (size && str[0] && str[0] != '\n') { 6373 if (str[size-1] == '\n') { 6374 str[size-1] = 0; 6375 size--; 6376 } 6377 error = security_context_to_sid(&selinux_state, value, size, 6378 &sid, GFP_KERNEL); 6379 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6380 if (!has_cap_mac_admin(true)) { 6381 struct audit_buffer *ab; 6382 size_t audit_size; 6383 6384 /* We strip a nul only if it is at the end, otherwise the 6385 * context contains a nul and we should audit that */ 6386 if (str[size - 1] == '\0') 6387 audit_size = size - 1; 6388 else 6389 audit_size = size; 6390 ab = audit_log_start(audit_context(), 6391 GFP_ATOMIC, 6392 AUDIT_SELINUX_ERR); 6393 audit_log_format(ab, "op=fscreate invalid_context="); 6394 audit_log_n_untrustedstring(ab, value, audit_size); 6395 audit_log_end(ab); 6396 6397 return error; 6398 } 6399 error = security_context_to_sid_force( 6400 &selinux_state, 6401 value, size, &sid); 6402 } 6403 if (error) 6404 return error; 6405 } 6406 6407 new = prepare_creds(); 6408 if (!new) 6409 return -ENOMEM; 6410 6411 /* Permission checking based on the specified context is 6412 performed during the actual operation (execve, 6413 open/mkdir/...), when we know the full context of the 6414 operation. See selinux_bprm_creds_for_exec for the execve 6415 checks and may_create for the file creation checks. The 6416 operation will then fail if the context is not permitted. */ 6417 tsec = selinux_cred(new); 6418 if (!strcmp(name, "exec")) { 6419 tsec->exec_sid = sid; 6420 } else if (!strcmp(name, "fscreate")) { 6421 tsec->create_sid = sid; 6422 } else if (!strcmp(name, "keycreate")) { 6423 if (sid) { 6424 error = avc_has_perm(&selinux_state, mysid, sid, 6425 SECCLASS_KEY, KEY__CREATE, NULL); 6426 if (error) 6427 goto abort_change; 6428 } 6429 tsec->keycreate_sid = sid; 6430 } else if (!strcmp(name, "sockcreate")) { 6431 tsec->sockcreate_sid = sid; 6432 } else if (!strcmp(name, "current")) { 6433 error = -EINVAL; 6434 if (sid == 0) 6435 goto abort_change; 6436 6437 /* Only allow single threaded processes to change context */ 6438 error = -EPERM; 6439 if (!current_is_single_threaded()) { 6440 error = security_bounded_transition(&selinux_state, 6441 tsec->sid, sid); 6442 if (error) 6443 goto abort_change; 6444 } 6445 6446 /* Check permissions for the transition. */ 6447 error = avc_has_perm(&selinux_state, 6448 tsec->sid, sid, SECCLASS_PROCESS, 6449 PROCESS__DYNTRANSITION, NULL); 6450 if (error) 6451 goto abort_change; 6452 6453 /* Check for ptracing, and update the task SID if ok. 6454 Otherwise, leave SID unchanged and fail. */ 6455 ptsid = ptrace_parent_sid(); 6456 if (ptsid != 0) { 6457 error = avc_has_perm(&selinux_state, 6458 ptsid, sid, SECCLASS_PROCESS, 6459 PROCESS__PTRACE, NULL); 6460 if (error) 6461 goto abort_change; 6462 } 6463 6464 tsec->sid = sid; 6465 } else { 6466 error = -EINVAL; 6467 goto abort_change; 6468 } 6469 6470 commit_creds(new); 6471 return size; 6472 6473 abort_change: 6474 abort_creds(new); 6475 return error; 6476 } 6477 6478 static int selinux_ismaclabel(const char *name) 6479 { 6480 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6481 } 6482 6483 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6484 { 6485 return security_sid_to_context(&selinux_state, secid, 6486 secdata, seclen); 6487 } 6488 6489 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6490 { 6491 return security_context_to_sid(&selinux_state, secdata, seclen, 6492 secid, GFP_KERNEL); 6493 } 6494 6495 static void selinux_release_secctx(char *secdata, u32 seclen) 6496 { 6497 kfree(secdata); 6498 } 6499 6500 static void selinux_inode_invalidate_secctx(struct inode *inode) 6501 { 6502 struct inode_security_struct *isec = selinux_inode(inode); 6503 6504 spin_lock(&isec->lock); 6505 isec->initialized = LABEL_INVALID; 6506 spin_unlock(&isec->lock); 6507 } 6508 6509 /* 6510 * called with inode->i_mutex locked 6511 */ 6512 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6513 { 6514 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6515 ctx, ctxlen, 0); 6516 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6517 return rc == -EOPNOTSUPP ? 0 : rc; 6518 } 6519 6520 /* 6521 * called with inode->i_mutex locked 6522 */ 6523 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6524 { 6525 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 6526 } 6527 6528 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6529 { 6530 int len = 0; 6531 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 6532 ctx, true); 6533 if (len < 0) 6534 return len; 6535 *ctxlen = len; 6536 return 0; 6537 } 6538 #ifdef CONFIG_KEYS 6539 6540 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6541 unsigned long flags) 6542 { 6543 const struct task_security_struct *tsec; 6544 struct key_security_struct *ksec; 6545 6546 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6547 if (!ksec) 6548 return -ENOMEM; 6549 6550 tsec = selinux_cred(cred); 6551 if (tsec->keycreate_sid) 6552 ksec->sid = tsec->keycreate_sid; 6553 else 6554 ksec->sid = tsec->sid; 6555 6556 k->security = ksec; 6557 return 0; 6558 } 6559 6560 static void selinux_key_free(struct key *k) 6561 { 6562 struct key_security_struct *ksec = k->security; 6563 6564 k->security = NULL; 6565 kfree(ksec); 6566 } 6567 6568 static int selinux_key_permission(key_ref_t key_ref, 6569 const struct cred *cred, 6570 enum key_need_perm need_perm) 6571 { 6572 struct key *key; 6573 struct key_security_struct *ksec; 6574 u32 perm, sid; 6575 6576 switch (need_perm) { 6577 case KEY_NEED_VIEW: 6578 perm = KEY__VIEW; 6579 break; 6580 case KEY_NEED_READ: 6581 perm = KEY__READ; 6582 break; 6583 case KEY_NEED_WRITE: 6584 perm = KEY__WRITE; 6585 break; 6586 case KEY_NEED_SEARCH: 6587 perm = KEY__SEARCH; 6588 break; 6589 case KEY_NEED_LINK: 6590 perm = KEY__LINK; 6591 break; 6592 case KEY_NEED_SETATTR: 6593 perm = KEY__SETATTR; 6594 break; 6595 case KEY_NEED_UNLINK: 6596 case KEY_SYSADMIN_OVERRIDE: 6597 case KEY_AUTHTOKEN_OVERRIDE: 6598 case KEY_DEFER_PERM_CHECK: 6599 return 0; 6600 default: 6601 WARN_ON(1); 6602 return -EPERM; 6603 6604 } 6605 6606 sid = cred_sid(cred); 6607 key = key_ref_to_ptr(key_ref); 6608 ksec = key->security; 6609 6610 return avc_has_perm(&selinux_state, 6611 sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6612 } 6613 6614 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6615 { 6616 struct key_security_struct *ksec = key->security; 6617 char *context = NULL; 6618 unsigned len; 6619 int rc; 6620 6621 rc = security_sid_to_context(&selinux_state, ksec->sid, 6622 &context, &len); 6623 if (!rc) 6624 rc = len; 6625 *_buffer = context; 6626 return rc; 6627 } 6628 6629 #ifdef CONFIG_KEY_NOTIFICATIONS 6630 static int selinux_watch_key(struct key *key) 6631 { 6632 struct key_security_struct *ksec = key->security; 6633 u32 sid = current_sid(); 6634 6635 return avc_has_perm(&selinux_state, 6636 sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6637 } 6638 #endif 6639 #endif 6640 6641 #ifdef CONFIG_SECURITY_INFINIBAND 6642 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6643 { 6644 struct common_audit_data ad; 6645 int err; 6646 u32 sid = 0; 6647 struct ib_security_struct *sec = ib_sec; 6648 struct lsm_ibpkey_audit ibpkey; 6649 6650 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6651 if (err) 6652 return err; 6653 6654 ad.type = LSM_AUDIT_DATA_IBPKEY; 6655 ibpkey.subnet_prefix = subnet_prefix; 6656 ibpkey.pkey = pkey_val; 6657 ad.u.ibpkey = &ibpkey; 6658 return avc_has_perm(&selinux_state, 6659 sec->sid, sid, 6660 SECCLASS_INFINIBAND_PKEY, 6661 INFINIBAND_PKEY__ACCESS, &ad); 6662 } 6663 6664 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6665 u8 port_num) 6666 { 6667 struct common_audit_data ad; 6668 int err; 6669 u32 sid = 0; 6670 struct ib_security_struct *sec = ib_sec; 6671 struct lsm_ibendport_audit ibendport; 6672 6673 err = security_ib_endport_sid(&selinux_state, dev_name, port_num, 6674 &sid); 6675 6676 if (err) 6677 return err; 6678 6679 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6680 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name)); 6681 ibendport.port = port_num; 6682 ad.u.ibendport = &ibendport; 6683 return avc_has_perm(&selinux_state, 6684 sec->sid, sid, 6685 SECCLASS_INFINIBAND_ENDPORT, 6686 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6687 } 6688 6689 static int selinux_ib_alloc_security(void **ib_sec) 6690 { 6691 struct ib_security_struct *sec; 6692 6693 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6694 if (!sec) 6695 return -ENOMEM; 6696 sec->sid = current_sid(); 6697 6698 *ib_sec = sec; 6699 return 0; 6700 } 6701 6702 static void selinux_ib_free_security(void *ib_sec) 6703 { 6704 kfree(ib_sec); 6705 } 6706 #endif 6707 6708 #ifdef CONFIG_BPF_SYSCALL 6709 static int selinux_bpf(int cmd, union bpf_attr *attr, 6710 unsigned int size) 6711 { 6712 u32 sid = current_sid(); 6713 int ret; 6714 6715 switch (cmd) { 6716 case BPF_MAP_CREATE: 6717 ret = avc_has_perm(&selinux_state, 6718 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6719 NULL); 6720 break; 6721 case BPF_PROG_LOAD: 6722 ret = avc_has_perm(&selinux_state, 6723 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6724 NULL); 6725 break; 6726 default: 6727 ret = 0; 6728 break; 6729 } 6730 6731 return ret; 6732 } 6733 6734 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6735 { 6736 u32 av = 0; 6737 6738 if (fmode & FMODE_READ) 6739 av |= BPF__MAP_READ; 6740 if (fmode & FMODE_WRITE) 6741 av |= BPF__MAP_WRITE; 6742 return av; 6743 } 6744 6745 /* This function will check the file pass through unix socket or binder to see 6746 * if it is a bpf related object. And apply correspinding checks on the bpf 6747 * object based on the type. The bpf maps and programs, not like other files and 6748 * socket, are using a shared anonymous inode inside the kernel as their inode. 6749 * So checking that inode cannot identify if the process have privilege to 6750 * access the bpf object and that's why we have to add this additional check in 6751 * selinux_file_receive and selinux_binder_transfer_files. 6752 */ 6753 static int bpf_fd_pass(struct file *file, u32 sid) 6754 { 6755 struct bpf_security_struct *bpfsec; 6756 struct bpf_prog *prog; 6757 struct bpf_map *map; 6758 int ret; 6759 6760 if (file->f_op == &bpf_map_fops) { 6761 map = file->private_data; 6762 bpfsec = map->security; 6763 ret = avc_has_perm(&selinux_state, 6764 sid, bpfsec->sid, SECCLASS_BPF, 6765 bpf_map_fmode_to_av(file->f_mode), NULL); 6766 if (ret) 6767 return ret; 6768 } else if (file->f_op == &bpf_prog_fops) { 6769 prog = file->private_data; 6770 bpfsec = prog->aux->security; 6771 ret = avc_has_perm(&selinux_state, 6772 sid, bpfsec->sid, SECCLASS_BPF, 6773 BPF__PROG_RUN, NULL); 6774 if (ret) 6775 return ret; 6776 } 6777 return 0; 6778 } 6779 6780 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6781 { 6782 u32 sid = current_sid(); 6783 struct bpf_security_struct *bpfsec; 6784 6785 bpfsec = map->security; 6786 return avc_has_perm(&selinux_state, 6787 sid, bpfsec->sid, SECCLASS_BPF, 6788 bpf_map_fmode_to_av(fmode), NULL); 6789 } 6790 6791 static int selinux_bpf_prog(struct bpf_prog *prog) 6792 { 6793 u32 sid = current_sid(); 6794 struct bpf_security_struct *bpfsec; 6795 6796 bpfsec = prog->aux->security; 6797 return avc_has_perm(&selinux_state, 6798 sid, bpfsec->sid, SECCLASS_BPF, 6799 BPF__PROG_RUN, NULL); 6800 } 6801 6802 static int selinux_bpf_map_alloc(struct bpf_map *map) 6803 { 6804 struct bpf_security_struct *bpfsec; 6805 6806 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6807 if (!bpfsec) 6808 return -ENOMEM; 6809 6810 bpfsec->sid = current_sid(); 6811 map->security = bpfsec; 6812 6813 return 0; 6814 } 6815 6816 static void selinux_bpf_map_free(struct bpf_map *map) 6817 { 6818 struct bpf_security_struct *bpfsec = map->security; 6819 6820 map->security = NULL; 6821 kfree(bpfsec); 6822 } 6823 6824 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6825 { 6826 struct bpf_security_struct *bpfsec; 6827 6828 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6829 if (!bpfsec) 6830 return -ENOMEM; 6831 6832 bpfsec->sid = current_sid(); 6833 aux->security = bpfsec; 6834 6835 return 0; 6836 } 6837 6838 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6839 { 6840 struct bpf_security_struct *bpfsec = aux->security; 6841 6842 aux->security = NULL; 6843 kfree(bpfsec); 6844 } 6845 #endif 6846 6847 static int selinux_lockdown(enum lockdown_reason what) 6848 { 6849 struct common_audit_data ad; 6850 u32 sid = current_sid(); 6851 int invalid_reason = (what <= LOCKDOWN_NONE) || 6852 (what == LOCKDOWN_INTEGRITY_MAX) || 6853 (what >= LOCKDOWN_CONFIDENTIALITY_MAX); 6854 6855 if (WARN(invalid_reason, "Invalid lockdown reason")) { 6856 audit_log(audit_context(), 6857 GFP_ATOMIC, AUDIT_SELINUX_ERR, 6858 "lockdown_reason=invalid"); 6859 return -EINVAL; 6860 } 6861 6862 ad.type = LSM_AUDIT_DATA_LOCKDOWN; 6863 ad.u.reason = what; 6864 6865 if (what <= LOCKDOWN_INTEGRITY_MAX) 6866 return avc_has_perm(&selinux_state, 6867 sid, sid, SECCLASS_LOCKDOWN, 6868 LOCKDOWN__INTEGRITY, &ad); 6869 else 6870 return avc_has_perm(&selinux_state, 6871 sid, sid, SECCLASS_LOCKDOWN, 6872 LOCKDOWN__CONFIDENTIALITY, &ad); 6873 } 6874 6875 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = { 6876 .lbs_cred = sizeof(struct task_security_struct), 6877 .lbs_file = sizeof(struct file_security_struct), 6878 .lbs_inode = sizeof(struct inode_security_struct), 6879 .lbs_ipc = sizeof(struct ipc_security_struct), 6880 .lbs_msg_msg = sizeof(struct msg_security_struct), 6881 }; 6882 6883 #ifdef CONFIG_PERF_EVENTS 6884 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6885 { 6886 u32 requested, sid = current_sid(); 6887 6888 if (type == PERF_SECURITY_OPEN) 6889 requested = PERF_EVENT__OPEN; 6890 else if (type == PERF_SECURITY_CPU) 6891 requested = PERF_EVENT__CPU; 6892 else if (type == PERF_SECURITY_KERNEL) 6893 requested = PERF_EVENT__KERNEL; 6894 else if (type == PERF_SECURITY_TRACEPOINT) 6895 requested = PERF_EVENT__TRACEPOINT; 6896 else 6897 return -EINVAL; 6898 6899 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT, 6900 requested, NULL); 6901 } 6902 6903 static int selinux_perf_event_alloc(struct perf_event *event) 6904 { 6905 struct perf_event_security_struct *perfsec; 6906 6907 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6908 if (!perfsec) 6909 return -ENOMEM; 6910 6911 perfsec->sid = current_sid(); 6912 event->security = perfsec; 6913 6914 return 0; 6915 } 6916 6917 static void selinux_perf_event_free(struct perf_event *event) 6918 { 6919 struct perf_event_security_struct *perfsec = event->security; 6920 6921 event->security = NULL; 6922 kfree(perfsec); 6923 } 6924 6925 static int selinux_perf_event_read(struct perf_event *event) 6926 { 6927 struct perf_event_security_struct *perfsec = event->security; 6928 u32 sid = current_sid(); 6929 6930 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6931 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6932 } 6933 6934 static int selinux_perf_event_write(struct perf_event *event) 6935 { 6936 struct perf_event_security_struct *perfsec = event->security; 6937 u32 sid = current_sid(); 6938 6939 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6940 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6941 } 6942 #endif 6943 6944 /* 6945 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6946 * 1. any hooks that don't belong to (2.) or (3.) below, 6947 * 2. hooks that both access structures allocated by other hooks, and allocate 6948 * structures that can be later accessed by other hooks (mostly "cloning" 6949 * hooks), 6950 * 3. hooks that only allocate structures that can be later accessed by other 6951 * hooks ("allocating" hooks). 6952 * 6953 * Please follow block comment delimiters in the list to keep this order. 6954 * 6955 * This ordering is needed for SELinux runtime disable to work at least somewhat 6956 * safely. Breaking the ordering rules above might lead to NULL pointer derefs 6957 * when disabling SELinux at runtime. 6958 */ 6959 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { 6960 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6961 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6962 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6963 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6964 6965 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6966 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6967 LSM_HOOK_INIT(capget, selinux_capget), 6968 LSM_HOOK_INIT(capset, selinux_capset), 6969 LSM_HOOK_INIT(capable, selinux_capable), 6970 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6971 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6972 LSM_HOOK_INIT(syslog, selinux_syslog), 6973 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6974 6975 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6976 6977 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 6978 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6979 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6980 6981 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), 6982 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 6983 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6984 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6985 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6986 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6987 LSM_HOOK_INIT(sb_mount, selinux_mount), 6988 LSM_HOOK_INIT(sb_umount, selinux_umount), 6989 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6990 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6991 6992 LSM_HOOK_INIT(move_mount, selinux_move_mount), 6993 6994 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6995 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 6996 6997 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 6998 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 6999 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7000 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7001 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7002 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7003 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7004 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7005 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7006 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7007 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7008 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7009 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7010 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7011 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7012 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7013 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7014 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7015 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7016 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7017 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7018 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7019 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7020 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7021 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7022 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7023 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7024 7025 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7026 7027 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7028 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7029 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7030 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7031 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7032 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7033 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7034 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7035 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7036 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7037 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7038 7039 LSM_HOOK_INIT(file_open, selinux_file_open), 7040 7041 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7042 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7043 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7044 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7045 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7046 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7047 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7048 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7049 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7050 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7051 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7052 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7053 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), 7054 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7055 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7056 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7057 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7058 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7059 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7060 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7061 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7062 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7063 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7064 7065 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7066 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7067 7068 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7069 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7070 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7071 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7072 7073 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7074 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7075 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7076 7077 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7078 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7079 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7080 7081 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7082 7083 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7084 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7085 7086 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7087 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7088 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7089 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7090 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7091 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7092 7093 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7094 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7095 7096 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7097 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7098 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7099 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7100 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7101 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7102 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7103 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7104 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7105 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7106 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7107 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7108 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7109 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7110 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7111 LSM_HOOK_INIT(socket_getpeersec_stream, 7112 selinux_socket_getpeersec_stream), 7113 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7114 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7115 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7116 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7117 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7118 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7119 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7120 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7121 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7122 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7123 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7124 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7125 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7126 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7127 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7128 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7129 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7130 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7131 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7132 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7133 #ifdef CONFIG_SECURITY_INFINIBAND 7134 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7135 LSM_HOOK_INIT(ib_endport_manage_subnet, 7136 selinux_ib_endport_manage_subnet), 7137 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7138 #endif 7139 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7140 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7141 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7142 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7143 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7144 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7145 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7146 selinux_xfrm_state_pol_flow_match), 7147 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7148 #endif 7149 7150 #ifdef CONFIG_KEYS 7151 LSM_HOOK_INIT(key_free, selinux_key_free), 7152 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7153 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7154 #ifdef CONFIG_KEY_NOTIFICATIONS 7155 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7156 #endif 7157 #endif 7158 7159 #ifdef CONFIG_AUDIT 7160 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7161 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7162 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7163 #endif 7164 7165 #ifdef CONFIG_BPF_SYSCALL 7166 LSM_HOOK_INIT(bpf, selinux_bpf), 7167 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7168 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7169 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7170 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7171 #endif 7172 7173 #ifdef CONFIG_PERF_EVENTS 7174 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7175 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7176 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7177 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7178 #endif 7179 7180 LSM_HOOK_INIT(locked_down, selinux_lockdown), 7181 7182 /* 7183 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7184 */ 7185 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7186 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7187 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7188 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt), 7189 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7190 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7191 #endif 7192 7193 /* 7194 * PUT "ALLOCATING" HOOKS HERE 7195 */ 7196 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7197 LSM_HOOK_INIT(msg_queue_alloc_security, 7198 selinux_msg_queue_alloc_security), 7199 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7200 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7201 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7202 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7203 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7204 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7205 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7206 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7207 #ifdef CONFIG_SECURITY_INFINIBAND 7208 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7209 #endif 7210 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7211 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7212 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7213 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7214 selinux_xfrm_state_alloc_acquire), 7215 #endif 7216 #ifdef CONFIG_KEYS 7217 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7218 #endif 7219 #ifdef CONFIG_AUDIT 7220 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7221 #endif 7222 #ifdef CONFIG_BPF_SYSCALL 7223 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7224 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7225 #endif 7226 #ifdef CONFIG_PERF_EVENTS 7227 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7228 #endif 7229 }; 7230 7231 static __init int selinux_init(void) 7232 { 7233 pr_info("SELinux: Initializing.\n"); 7234 7235 memset(&selinux_state, 0, sizeof(selinux_state)); 7236 enforcing_set(&selinux_state, selinux_enforcing_boot); 7237 selinux_state.checkreqprot = selinux_checkreqprot_boot; 7238 selinux_ss_init(&selinux_state.ss); 7239 selinux_avc_init(&selinux_state.avc); 7240 mutex_init(&selinux_state.status_lock); 7241 7242 /* Set the security state for the initial task. */ 7243 cred_init_security(); 7244 7245 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7246 7247 avc_init(); 7248 7249 avtab_cache_init(); 7250 7251 ebitmap_cache_init(); 7252 7253 hashtab_cache_init(); 7254 7255 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7256 7257 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7258 panic("SELinux: Unable to register AVC netcache callback\n"); 7259 7260 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7261 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7262 7263 if (selinux_enforcing_boot) 7264 pr_debug("SELinux: Starting in enforcing mode\n"); 7265 else 7266 pr_debug("SELinux: Starting in permissive mode\n"); 7267 7268 fs_validate_description("selinux", selinux_fs_parameters); 7269 7270 return 0; 7271 } 7272 7273 static void delayed_superblock_init(struct super_block *sb, void *unused) 7274 { 7275 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7276 } 7277 7278 void selinux_complete_init(void) 7279 { 7280 pr_debug("SELinux: Completing initialization.\n"); 7281 7282 /* Set up any superblocks initialized prior to the policy load. */ 7283 pr_debug("SELinux: Setting up existing superblocks.\n"); 7284 iterate_supers(delayed_superblock_init, NULL); 7285 } 7286 7287 /* SELinux requires early initialization in order to label 7288 all processes and objects when they are created. */ 7289 DEFINE_LSM(selinux) = { 7290 .name = "selinux", 7291 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7292 .enabled = &selinux_enabled_boot, 7293 .blobs = &selinux_blob_sizes, 7294 .init = selinux_init, 7295 }; 7296 7297 #if defined(CONFIG_NETFILTER) 7298 7299 static const struct nf_hook_ops selinux_nf_ops[] = { 7300 { 7301 .hook = selinux_ipv4_postroute, 7302 .pf = NFPROTO_IPV4, 7303 .hooknum = NF_INET_POST_ROUTING, 7304 .priority = NF_IP_PRI_SELINUX_LAST, 7305 }, 7306 { 7307 .hook = selinux_ipv4_forward, 7308 .pf = NFPROTO_IPV4, 7309 .hooknum = NF_INET_FORWARD, 7310 .priority = NF_IP_PRI_SELINUX_FIRST, 7311 }, 7312 { 7313 .hook = selinux_ipv4_output, 7314 .pf = NFPROTO_IPV4, 7315 .hooknum = NF_INET_LOCAL_OUT, 7316 .priority = NF_IP_PRI_SELINUX_FIRST, 7317 }, 7318 #if IS_ENABLED(CONFIG_IPV6) 7319 { 7320 .hook = selinux_ipv6_postroute, 7321 .pf = NFPROTO_IPV6, 7322 .hooknum = NF_INET_POST_ROUTING, 7323 .priority = NF_IP6_PRI_SELINUX_LAST, 7324 }, 7325 { 7326 .hook = selinux_ipv6_forward, 7327 .pf = NFPROTO_IPV6, 7328 .hooknum = NF_INET_FORWARD, 7329 .priority = NF_IP6_PRI_SELINUX_FIRST, 7330 }, 7331 { 7332 .hook = selinux_ipv6_output, 7333 .pf = NFPROTO_IPV6, 7334 .hooknum = NF_INET_LOCAL_OUT, 7335 .priority = NF_IP6_PRI_SELINUX_FIRST, 7336 }, 7337 #endif /* IPV6 */ 7338 }; 7339 7340 static int __net_init selinux_nf_register(struct net *net) 7341 { 7342 return nf_register_net_hooks(net, selinux_nf_ops, 7343 ARRAY_SIZE(selinux_nf_ops)); 7344 } 7345 7346 static void __net_exit selinux_nf_unregister(struct net *net) 7347 { 7348 nf_unregister_net_hooks(net, selinux_nf_ops, 7349 ARRAY_SIZE(selinux_nf_ops)); 7350 } 7351 7352 static struct pernet_operations selinux_net_ops = { 7353 .init = selinux_nf_register, 7354 .exit = selinux_nf_unregister, 7355 }; 7356 7357 static int __init selinux_nf_ip_init(void) 7358 { 7359 int err; 7360 7361 if (!selinux_enabled_boot) 7362 return 0; 7363 7364 pr_debug("SELinux: Registering netfilter hooks\n"); 7365 7366 err = register_pernet_subsys(&selinux_net_ops); 7367 if (err) 7368 panic("SELinux: register_pernet_subsys: error %d\n", err); 7369 7370 return 0; 7371 } 7372 __initcall(selinux_nf_ip_init); 7373 7374 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7375 static void selinux_nf_ip_exit(void) 7376 { 7377 pr_debug("SELinux: Unregistering netfilter hooks\n"); 7378 7379 unregister_pernet_subsys(&selinux_net_ops); 7380 } 7381 #endif 7382 7383 #else /* CONFIG_NETFILTER */ 7384 7385 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7386 #define selinux_nf_ip_exit() 7387 #endif 7388 7389 #endif /* CONFIG_NETFILTER */ 7390 7391 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7392 int selinux_disable(struct selinux_state *state) 7393 { 7394 if (selinux_initialized(state)) { 7395 /* Not permitted after initial policy load. */ 7396 return -EINVAL; 7397 } 7398 7399 if (selinux_disabled(state)) { 7400 /* Only do this once. */ 7401 return -EINVAL; 7402 } 7403 7404 selinux_mark_disabled(state); 7405 7406 pr_info("SELinux: Disabled at runtime.\n"); 7407 7408 /* 7409 * Unregister netfilter hooks. 7410 * Must be done before security_delete_hooks() to avoid breaking 7411 * runtime disable. 7412 */ 7413 selinux_nf_ip_exit(); 7414 7415 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 7416 7417 /* Try to destroy the avc node cache */ 7418 avc_disable(); 7419 7420 /* Unregister selinuxfs. */ 7421 exit_sel_fs(); 7422 7423 return 0; 7424 } 7425 #endif 7426