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 case FIBMAP: 3613 case FIGETBSZ: 3614 case FS_IOC_GETFLAGS: 3615 case FS_IOC_GETVERSION: 3616 error = file_has_perm(cred, file, FILE__GETATTR); 3617 break; 3618 3619 case FS_IOC_SETFLAGS: 3620 case FS_IOC_SETVERSION: 3621 error = file_has_perm(cred, file, FILE__SETATTR); 3622 break; 3623 3624 /* sys_ioctl() checks */ 3625 case FIONBIO: 3626 case FIOASYNC: 3627 error = file_has_perm(cred, file, 0); 3628 break; 3629 3630 case KDSKBENT: 3631 case KDSKBSENT: 3632 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3633 CAP_OPT_NONE, true); 3634 break; 3635 3636 /* default case assumes that the command will go 3637 * to the file's ioctl() function. 3638 */ 3639 default: 3640 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3641 } 3642 return error; 3643 } 3644 3645 static int default_noexec __ro_after_init; 3646 3647 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3648 { 3649 const struct cred *cred = current_cred(); 3650 u32 sid = cred_sid(cred); 3651 int rc = 0; 3652 3653 if (default_noexec && 3654 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3655 (!shared && (prot & PROT_WRITE)))) { 3656 /* 3657 * We are making executable an anonymous mapping or a 3658 * private file mapping that will also be writable. 3659 * This has an additional check. 3660 */ 3661 rc = avc_has_perm(&selinux_state, 3662 sid, sid, SECCLASS_PROCESS, 3663 PROCESS__EXECMEM, NULL); 3664 if (rc) 3665 goto error; 3666 } 3667 3668 if (file) { 3669 /* read access is always possible with a mapping */ 3670 u32 av = FILE__READ; 3671 3672 /* write access only matters if the mapping is shared */ 3673 if (shared && (prot & PROT_WRITE)) 3674 av |= FILE__WRITE; 3675 3676 if (prot & PROT_EXEC) 3677 av |= FILE__EXECUTE; 3678 3679 return file_has_perm(cred, file, av); 3680 } 3681 3682 error: 3683 return rc; 3684 } 3685 3686 static int selinux_mmap_addr(unsigned long addr) 3687 { 3688 int rc = 0; 3689 3690 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3691 u32 sid = current_sid(); 3692 rc = avc_has_perm(&selinux_state, 3693 sid, sid, SECCLASS_MEMPROTECT, 3694 MEMPROTECT__MMAP_ZERO, NULL); 3695 } 3696 3697 return rc; 3698 } 3699 3700 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3701 unsigned long prot, unsigned long flags) 3702 { 3703 struct common_audit_data ad; 3704 int rc; 3705 3706 if (file) { 3707 ad.type = LSM_AUDIT_DATA_FILE; 3708 ad.u.file = file; 3709 rc = inode_has_perm(current_cred(), file_inode(file), 3710 FILE__MAP, &ad); 3711 if (rc) 3712 return rc; 3713 } 3714 3715 if (checkreqprot_get(&selinux_state)) 3716 prot = reqprot; 3717 3718 return file_map_prot_check(file, prot, 3719 (flags & MAP_TYPE) == MAP_SHARED); 3720 } 3721 3722 static int selinux_file_mprotect(struct vm_area_struct *vma, 3723 unsigned long reqprot, 3724 unsigned long prot) 3725 { 3726 const struct cred *cred = current_cred(); 3727 u32 sid = cred_sid(cred); 3728 3729 if (checkreqprot_get(&selinux_state)) 3730 prot = reqprot; 3731 3732 if (default_noexec && 3733 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3734 int rc = 0; 3735 if (vma->vm_start >= vma->vm_mm->start_brk && 3736 vma->vm_end <= vma->vm_mm->brk) { 3737 rc = avc_has_perm(&selinux_state, 3738 sid, sid, SECCLASS_PROCESS, 3739 PROCESS__EXECHEAP, NULL); 3740 } else if (!vma->vm_file && 3741 ((vma->vm_start <= vma->vm_mm->start_stack && 3742 vma->vm_end >= vma->vm_mm->start_stack) || 3743 vma_is_stack_for_current(vma))) { 3744 rc = avc_has_perm(&selinux_state, 3745 sid, sid, SECCLASS_PROCESS, 3746 PROCESS__EXECSTACK, NULL); 3747 } else if (vma->vm_file && vma->anon_vma) { 3748 /* 3749 * We are making executable a file mapping that has 3750 * had some COW done. Since pages might have been 3751 * written, check ability to execute the possibly 3752 * modified content. This typically should only 3753 * occur for text relocations. 3754 */ 3755 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3756 } 3757 if (rc) 3758 return rc; 3759 } 3760 3761 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3762 } 3763 3764 static int selinux_file_lock(struct file *file, unsigned int cmd) 3765 { 3766 const struct cred *cred = current_cred(); 3767 3768 return file_has_perm(cred, file, FILE__LOCK); 3769 } 3770 3771 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3772 unsigned long arg) 3773 { 3774 const struct cred *cred = current_cred(); 3775 int err = 0; 3776 3777 switch (cmd) { 3778 case F_SETFL: 3779 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3780 err = file_has_perm(cred, file, FILE__WRITE); 3781 break; 3782 } 3783 fallthrough; 3784 case F_SETOWN: 3785 case F_SETSIG: 3786 case F_GETFL: 3787 case F_GETOWN: 3788 case F_GETSIG: 3789 case F_GETOWNER_UIDS: 3790 /* Just check FD__USE permission */ 3791 err = file_has_perm(cred, file, 0); 3792 break; 3793 case F_GETLK: 3794 case F_SETLK: 3795 case F_SETLKW: 3796 case F_OFD_GETLK: 3797 case F_OFD_SETLK: 3798 case F_OFD_SETLKW: 3799 #if BITS_PER_LONG == 32 3800 case F_GETLK64: 3801 case F_SETLK64: 3802 case F_SETLKW64: 3803 #endif 3804 err = file_has_perm(cred, file, FILE__LOCK); 3805 break; 3806 } 3807 3808 return err; 3809 } 3810 3811 static void selinux_file_set_fowner(struct file *file) 3812 { 3813 struct file_security_struct *fsec; 3814 3815 fsec = selinux_file(file); 3816 fsec->fown_sid = current_sid(); 3817 } 3818 3819 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3820 struct fown_struct *fown, int signum) 3821 { 3822 struct file *file; 3823 u32 sid = task_sid(tsk); 3824 u32 perm; 3825 struct file_security_struct *fsec; 3826 3827 /* struct fown_struct is never outside the context of a struct file */ 3828 file = container_of(fown, struct file, f_owner); 3829 3830 fsec = selinux_file(file); 3831 3832 if (!signum) 3833 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3834 else 3835 perm = signal_to_av(signum); 3836 3837 return avc_has_perm(&selinux_state, 3838 fsec->fown_sid, sid, 3839 SECCLASS_PROCESS, perm, NULL); 3840 } 3841 3842 static int selinux_file_receive(struct file *file) 3843 { 3844 const struct cred *cred = current_cred(); 3845 3846 return file_has_perm(cred, file, file_to_av(file)); 3847 } 3848 3849 static int selinux_file_open(struct file *file) 3850 { 3851 struct file_security_struct *fsec; 3852 struct inode_security_struct *isec; 3853 3854 fsec = selinux_file(file); 3855 isec = inode_security(file_inode(file)); 3856 /* 3857 * Save inode label and policy sequence number 3858 * at open-time so that selinux_file_permission 3859 * can determine whether revalidation is necessary. 3860 * Task label is already saved in the file security 3861 * struct as its SID. 3862 */ 3863 fsec->isid = isec->sid; 3864 fsec->pseqno = avc_policy_seqno(&selinux_state); 3865 /* 3866 * Since the inode label or policy seqno may have changed 3867 * between the selinux_inode_permission check and the saving 3868 * of state above, recheck that access is still permitted. 3869 * Otherwise, access might never be revalidated against the 3870 * new inode label or new policy. 3871 * This check is not redundant - do not remove. 3872 */ 3873 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3874 } 3875 3876 /* task security operations */ 3877 3878 static int selinux_task_alloc(struct task_struct *task, 3879 unsigned long clone_flags) 3880 { 3881 u32 sid = current_sid(); 3882 3883 return avc_has_perm(&selinux_state, 3884 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3885 } 3886 3887 /* 3888 * prepare a new set of credentials for modification 3889 */ 3890 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3891 gfp_t gfp) 3892 { 3893 const struct task_security_struct *old_tsec = selinux_cred(old); 3894 struct task_security_struct *tsec = selinux_cred(new); 3895 3896 *tsec = *old_tsec; 3897 return 0; 3898 } 3899 3900 /* 3901 * transfer the SELinux data to a blank set of creds 3902 */ 3903 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3904 { 3905 const struct task_security_struct *old_tsec = selinux_cred(old); 3906 struct task_security_struct *tsec = selinux_cred(new); 3907 3908 *tsec = *old_tsec; 3909 } 3910 3911 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 3912 { 3913 *secid = cred_sid(c); 3914 } 3915 3916 /* 3917 * set the security data for a kernel service 3918 * - all the creation contexts are set to unlabelled 3919 */ 3920 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3921 { 3922 struct task_security_struct *tsec = selinux_cred(new); 3923 u32 sid = current_sid(); 3924 int ret; 3925 3926 ret = avc_has_perm(&selinux_state, 3927 sid, secid, 3928 SECCLASS_KERNEL_SERVICE, 3929 KERNEL_SERVICE__USE_AS_OVERRIDE, 3930 NULL); 3931 if (ret == 0) { 3932 tsec->sid = secid; 3933 tsec->create_sid = 0; 3934 tsec->keycreate_sid = 0; 3935 tsec->sockcreate_sid = 0; 3936 } 3937 return ret; 3938 } 3939 3940 /* 3941 * set the file creation context in a security record to the same as the 3942 * objective context of the specified inode 3943 */ 3944 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3945 { 3946 struct inode_security_struct *isec = inode_security(inode); 3947 struct task_security_struct *tsec = selinux_cred(new); 3948 u32 sid = current_sid(); 3949 int ret; 3950 3951 ret = avc_has_perm(&selinux_state, 3952 sid, isec->sid, 3953 SECCLASS_KERNEL_SERVICE, 3954 KERNEL_SERVICE__CREATE_FILES_AS, 3955 NULL); 3956 3957 if (ret == 0) 3958 tsec->create_sid = isec->sid; 3959 return ret; 3960 } 3961 3962 static int selinux_kernel_module_request(char *kmod_name) 3963 { 3964 struct common_audit_data ad; 3965 3966 ad.type = LSM_AUDIT_DATA_KMOD; 3967 ad.u.kmod_name = kmod_name; 3968 3969 return avc_has_perm(&selinux_state, 3970 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 3971 SYSTEM__MODULE_REQUEST, &ad); 3972 } 3973 3974 static int selinux_kernel_module_from_file(struct file *file) 3975 { 3976 struct common_audit_data ad; 3977 struct inode_security_struct *isec; 3978 struct file_security_struct *fsec; 3979 u32 sid = current_sid(); 3980 int rc; 3981 3982 /* init_module */ 3983 if (file == NULL) 3984 return avc_has_perm(&selinux_state, 3985 sid, sid, SECCLASS_SYSTEM, 3986 SYSTEM__MODULE_LOAD, NULL); 3987 3988 /* finit_module */ 3989 3990 ad.type = LSM_AUDIT_DATA_FILE; 3991 ad.u.file = file; 3992 3993 fsec = selinux_file(file); 3994 if (sid != fsec->sid) { 3995 rc = avc_has_perm(&selinux_state, 3996 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 3997 if (rc) 3998 return rc; 3999 } 4000 4001 isec = inode_security(file_inode(file)); 4002 return avc_has_perm(&selinux_state, 4003 sid, isec->sid, SECCLASS_SYSTEM, 4004 SYSTEM__MODULE_LOAD, &ad); 4005 } 4006 4007 static int selinux_kernel_read_file(struct file *file, 4008 enum kernel_read_file_id id) 4009 { 4010 int rc = 0; 4011 4012 switch (id) { 4013 case READING_MODULE: 4014 rc = selinux_kernel_module_from_file(file); 4015 break; 4016 default: 4017 break; 4018 } 4019 4020 return rc; 4021 } 4022 4023 static int selinux_kernel_load_data(enum kernel_load_data_id id) 4024 { 4025 int rc = 0; 4026 4027 switch (id) { 4028 case LOADING_MODULE: 4029 rc = selinux_kernel_module_from_file(NULL); 4030 default: 4031 break; 4032 } 4033 4034 return rc; 4035 } 4036 4037 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4038 { 4039 return avc_has_perm(&selinux_state, 4040 current_sid(), task_sid(p), SECCLASS_PROCESS, 4041 PROCESS__SETPGID, NULL); 4042 } 4043 4044 static int selinux_task_getpgid(struct task_struct *p) 4045 { 4046 return avc_has_perm(&selinux_state, 4047 current_sid(), task_sid(p), SECCLASS_PROCESS, 4048 PROCESS__GETPGID, NULL); 4049 } 4050 4051 static int selinux_task_getsid(struct task_struct *p) 4052 { 4053 return avc_has_perm(&selinux_state, 4054 current_sid(), task_sid(p), SECCLASS_PROCESS, 4055 PROCESS__GETSESSION, NULL); 4056 } 4057 4058 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 4059 { 4060 *secid = task_sid(p); 4061 } 4062 4063 static int selinux_task_setnice(struct task_struct *p, int nice) 4064 { 4065 return avc_has_perm(&selinux_state, 4066 current_sid(), task_sid(p), SECCLASS_PROCESS, 4067 PROCESS__SETSCHED, NULL); 4068 } 4069 4070 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4071 { 4072 return avc_has_perm(&selinux_state, 4073 current_sid(), task_sid(p), SECCLASS_PROCESS, 4074 PROCESS__SETSCHED, NULL); 4075 } 4076 4077 static int selinux_task_getioprio(struct task_struct *p) 4078 { 4079 return avc_has_perm(&selinux_state, 4080 current_sid(), task_sid(p), SECCLASS_PROCESS, 4081 PROCESS__GETSCHED, NULL); 4082 } 4083 4084 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4085 unsigned int flags) 4086 { 4087 u32 av = 0; 4088 4089 if (!flags) 4090 return 0; 4091 if (flags & LSM_PRLIMIT_WRITE) 4092 av |= PROCESS__SETRLIMIT; 4093 if (flags & LSM_PRLIMIT_READ) 4094 av |= PROCESS__GETRLIMIT; 4095 return avc_has_perm(&selinux_state, 4096 cred_sid(cred), cred_sid(tcred), 4097 SECCLASS_PROCESS, av, NULL); 4098 } 4099 4100 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4101 struct rlimit *new_rlim) 4102 { 4103 struct rlimit *old_rlim = p->signal->rlim + resource; 4104 4105 /* Control the ability to change the hard limit (whether 4106 lowering or raising it), so that the hard limit can 4107 later be used as a safe reset point for the soft limit 4108 upon context transitions. See selinux_bprm_committing_creds. */ 4109 if (old_rlim->rlim_max != new_rlim->rlim_max) 4110 return avc_has_perm(&selinux_state, 4111 current_sid(), task_sid(p), 4112 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4113 4114 return 0; 4115 } 4116 4117 static int selinux_task_setscheduler(struct task_struct *p) 4118 { 4119 return avc_has_perm(&selinux_state, 4120 current_sid(), task_sid(p), SECCLASS_PROCESS, 4121 PROCESS__SETSCHED, NULL); 4122 } 4123 4124 static int selinux_task_getscheduler(struct task_struct *p) 4125 { 4126 return avc_has_perm(&selinux_state, 4127 current_sid(), task_sid(p), SECCLASS_PROCESS, 4128 PROCESS__GETSCHED, NULL); 4129 } 4130 4131 static int selinux_task_movememory(struct task_struct *p) 4132 { 4133 return avc_has_perm(&selinux_state, 4134 current_sid(), task_sid(p), SECCLASS_PROCESS, 4135 PROCESS__SETSCHED, NULL); 4136 } 4137 4138 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4139 int sig, const struct cred *cred) 4140 { 4141 u32 secid; 4142 u32 perm; 4143 4144 if (!sig) 4145 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4146 else 4147 perm = signal_to_av(sig); 4148 if (!cred) 4149 secid = current_sid(); 4150 else 4151 secid = cred_sid(cred); 4152 return avc_has_perm(&selinux_state, 4153 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL); 4154 } 4155 4156 static void selinux_task_to_inode(struct task_struct *p, 4157 struct inode *inode) 4158 { 4159 struct inode_security_struct *isec = selinux_inode(inode); 4160 u32 sid = task_sid(p); 4161 4162 spin_lock(&isec->lock); 4163 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4164 isec->sid = sid; 4165 isec->initialized = LABEL_INITIALIZED; 4166 spin_unlock(&isec->lock); 4167 } 4168 4169 /* Returns error only if unable to parse addresses */ 4170 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4171 struct common_audit_data *ad, u8 *proto) 4172 { 4173 int offset, ihlen, ret = -EINVAL; 4174 struct iphdr _iph, *ih; 4175 4176 offset = skb_network_offset(skb); 4177 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4178 if (ih == NULL) 4179 goto out; 4180 4181 ihlen = ih->ihl * 4; 4182 if (ihlen < sizeof(_iph)) 4183 goto out; 4184 4185 ad->u.net->v4info.saddr = ih->saddr; 4186 ad->u.net->v4info.daddr = ih->daddr; 4187 ret = 0; 4188 4189 if (proto) 4190 *proto = ih->protocol; 4191 4192 switch (ih->protocol) { 4193 case IPPROTO_TCP: { 4194 struct tcphdr _tcph, *th; 4195 4196 if (ntohs(ih->frag_off) & IP_OFFSET) 4197 break; 4198 4199 offset += ihlen; 4200 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4201 if (th == NULL) 4202 break; 4203 4204 ad->u.net->sport = th->source; 4205 ad->u.net->dport = th->dest; 4206 break; 4207 } 4208 4209 case IPPROTO_UDP: { 4210 struct udphdr _udph, *uh; 4211 4212 if (ntohs(ih->frag_off) & IP_OFFSET) 4213 break; 4214 4215 offset += ihlen; 4216 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4217 if (uh == NULL) 4218 break; 4219 4220 ad->u.net->sport = uh->source; 4221 ad->u.net->dport = uh->dest; 4222 break; 4223 } 4224 4225 case IPPROTO_DCCP: { 4226 struct dccp_hdr _dccph, *dh; 4227 4228 if (ntohs(ih->frag_off) & IP_OFFSET) 4229 break; 4230 4231 offset += ihlen; 4232 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4233 if (dh == NULL) 4234 break; 4235 4236 ad->u.net->sport = dh->dccph_sport; 4237 ad->u.net->dport = dh->dccph_dport; 4238 break; 4239 } 4240 4241 #if IS_ENABLED(CONFIG_IP_SCTP) 4242 case IPPROTO_SCTP: { 4243 struct sctphdr _sctph, *sh; 4244 4245 if (ntohs(ih->frag_off) & IP_OFFSET) 4246 break; 4247 4248 offset += ihlen; 4249 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4250 if (sh == NULL) 4251 break; 4252 4253 ad->u.net->sport = sh->source; 4254 ad->u.net->dport = sh->dest; 4255 break; 4256 } 4257 #endif 4258 default: 4259 break; 4260 } 4261 out: 4262 return ret; 4263 } 4264 4265 #if IS_ENABLED(CONFIG_IPV6) 4266 4267 /* Returns error only if unable to parse addresses */ 4268 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4269 struct common_audit_data *ad, u8 *proto) 4270 { 4271 u8 nexthdr; 4272 int ret = -EINVAL, offset; 4273 struct ipv6hdr _ipv6h, *ip6; 4274 __be16 frag_off; 4275 4276 offset = skb_network_offset(skb); 4277 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4278 if (ip6 == NULL) 4279 goto out; 4280 4281 ad->u.net->v6info.saddr = ip6->saddr; 4282 ad->u.net->v6info.daddr = ip6->daddr; 4283 ret = 0; 4284 4285 nexthdr = ip6->nexthdr; 4286 offset += sizeof(_ipv6h); 4287 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4288 if (offset < 0) 4289 goto out; 4290 4291 if (proto) 4292 *proto = nexthdr; 4293 4294 switch (nexthdr) { 4295 case IPPROTO_TCP: { 4296 struct tcphdr _tcph, *th; 4297 4298 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4299 if (th == NULL) 4300 break; 4301 4302 ad->u.net->sport = th->source; 4303 ad->u.net->dport = th->dest; 4304 break; 4305 } 4306 4307 case IPPROTO_UDP: { 4308 struct udphdr _udph, *uh; 4309 4310 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4311 if (uh == NULL) 4312 break; 4313 4314 ad->u.net->sport = uh->source; 4315 ad->u.net->dport = uh->dest; 4316 break; 4317 } 4318 4319 case IPPROTO_DCCP: { 4320 struct dccp_hdr _dccph, *dh; 4321 4322 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4323 if (dh == NULL) 4324 break; 4325 4326 ad->u.net->sport = dh->dccph_sport; 4327 ad->u.net->dport = dh->dccph_dport; 4328 break; 4329 } 4330 4331 #if IS_ENABLED(CONFIG_IP_SCTP) 4332 case IPPROTO_SCTP: { 4333 struct sctphdr _sctph, *sh; 4334 4335 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4336 if (sh == NULL) 4337 break; 4338 4339 ad->u.net->sport = sh->source; 4340 ad->u.net->dport = sh->dest; 4341 break; 4342 } 4343 #endif 4344 /* includes fragments */ 4345 default: 4346 break; 4347 } 4348 out: 4349 return ret; 4350 } 4351 4352 #endif /* IPV6 */ 4353 4354 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4355 char **_addrp, int src, u8 *proto) 4356 { 4357 char *addrp; 4358 int ret; 4359 4360 switch (ad->u.net->family) { 4361 case PF_INET: 4362 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4363 if (ret) 4364 goto parse_error; 4365 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4366 &ad->u.net->v4info.daddr); 4367 goto okay; 4368 4369 #if IS_ENABLED(CONFIG_IPV6) 4370 case PF_INET6: 4371 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4372 if (ret) 4373 goto parse_error; 4374 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4375 &ad->u.net->v6info.daddr); 4376 goto okay; 4377 #endif /* IPV6 */ 4378 default: 4379 addrp = NULL; 4380 goto okay; 4381 } 4382 4383 parse_error: 4384 pr_warn( 4385 "SELinux: failure in selinux_parse_skb()," 4386 " unable to parse packet\n"); 4387 return ret; 4388 4389 okay: 4390 if (_addrp) 4391 *_addrp = addrp; 4392 return 0; 4393 } 4394 4395 /** 4396 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4397 * @skb: the packet 4398 * @family: protocol family 4399 * @sid: the packet's peer label SID 4400 * 4401 * Description: 4402 * Check the various different forms of network peer labeling and determine 4403 * the peer label/SID for the packet; most of the magic actually occurs in 4404 * the security server function security_net_peersid_cmp(). The function 4405 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4406 * or -EACCES if @sid is invalid due to inconsistencies with the different 4407 * peer labels. 4408 * 4409 */ 4410 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4411 { 4412 int err; 4413 u32 xfrm_sid; 4414 u32 nlbl_sid; 4415 u32 nlbl_type; 4416 4417 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4418 if (unlikely(err)) 4419 return -EACCES; 4420 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4421 if (unlikely(err)) 4422 return -EACCES; 4423 4424 err = security_net_peersid_resolve(&selinux_state, nlbl_sid, 4425 nlbl_type, xfrm_sid, sid); 4426 if (unlikely(err)) { 4427 pr_warn( 4428 "SELinux: failure in selinux_skb_peerlbl_sid()," 4429 " unable to determine packet's peer label\n"); 4430 return -EACCES; 4431 } 4432 4433 return 0; 4434 } 4435 4436 /** 4437 * selinux_conn_sid - Determine the child socket label for a connection 4438 * @sk_sid: the parent socket's SID 4439 * @skb_sid: the packet's SID 4440 * @conn_sid: the resulting connection SID 4441 * 4442 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4443 * combined with the MLS information from @skb_sid in order to create 4444 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4445 * of @sk_sid. Returns zero on success, negative values on failure. 4446 * 4447 */ 4448 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4449 { 4450 int err = 0; 4451 4452 if (skb_sid != SECSID_NULL) 4453 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid, 4454 conn_sid); 4455 else 4456 *conn_sid = sk_sid; 4457 4458 return err; 4459 } 4460 4461 /* socket security operations */ 4462 4463 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4464 u16 secclass, u32 *socksid) 4465 { 4466 if (tsec->sockcreate_sid > SECSID_NULL) { 4467 *socksid = tsec->sockcreate_sid; 4468 return 0; 4469 } 4470 4471 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid, 4472 secclass, NULL, socksid); 4473 } 4474 4475 static int sock_has_perm(struct sock *sk, u32 perms) 4476 { 4477 struct sk_security_struct *sksec = sk->sk_security; 4478 struct common_audit_data ad; 4479 struct lsm_network_audit net = {0,}; 4480 4481 if (sksec->sid == SECINITSID_KERNEL) 4482 return 0; 4483 4484 ad.type = LSM_AUDIT_DATA_NET; 4485 ad.u.net = &net; 4486 ad.u.net->sk = sk; 4487 4488 return avc_has_perm(&selinux_state, 4489 current_sid(), sksec->sid, sksec->sclass, perms, 4490 &ad); 4491 } 4492 4493 static int selinux_socket_create(int family, int type, 4494 int protocol, int kern) 4495 { 4496 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4497 u32 newsid; 4498 u16 secclass; 4499 int rc; 4500 4501 if (kern) 4502 return 0; 4503 4504 secclass = socket_type_to_security_class(family, type, protocol); 4505 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4506 if (rc) 4507 return rc; 4508 4509 return avc_has_perm(&selinux_state, 4510 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4511 } 4512 4513 static int selinux_socket_post_create(struct socket *sock, int family, 4514 int type, int protocol, int kern) 4515 { 4516 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4517 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4518 struct sk_security_struct *sksec; 4519 u16 sclass = socket_type_to_security_class(family, type, protocol); 4520 u32 sid = SECINITSID_KERNEL; 4521 int err = 0; 4522 4523 if (!kern) { 4524 err = socket_sockcreate_sid(tsec, sclass, &sid); 4525 if (err) 4526 return err; 4527 } 4528 4529 isec->sclass = sclass; 4530 isec->sid = sid; 4531 isec->initialized = LABEL_INITIALIZED; 4532 4533 if (sock->sk) { 4534 sksec = sock->sk->sk_security; 4535 sksec->sclass = sclass; 4536 sksec->sid = sid; 4537 /* Allows detection of the first association on this socket */ 4538 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4539 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4540 4541 err = selinux_netlbl_socket_post_create(sock->sk, family); 4542 } 4543 4544 return err; 4545 } 4546 4547 static int selinux_socket_socketpair(struct socket *socka, 4548 struct socket *sockb) 4549 { 4550 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4551 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4552 4553 sksec_a->peer_sid = sksec_b->sid; 4554 sksec_b->peer_sid = sksec_a->sid; 4555 4556 return 0; 4557 } 4558 4559 /* Range of port numbers used to automatically bind. 4560 Need to determine whether we should perform a name_bind 4561 permission check between the socket and the port number. */ 4562 4563 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4564 { 4565 struct sock *sk = sock->sk; 4566 struct sk_security_struct *sksec = sk->sk_security; 4567 u16 family; 4568 int err; 4569 4570 err = sock_has_perm(sk, SOCKET__BIND); 4571 if (err) 4572 goto out; 4573 4574 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4575 family = sk->sk_family; 4576 if (family == PF_INET || family == PF_INET6) { 4577 char *addrp; 4578 struct common_audit_data ad; 4579 struct lsm_network_audit net = {0,}; 4580 struct sockaddr_in *addr4 = NULL; 4581 struct sockaddr_in6 *addr6 = NULL; 4582 u16 family_sa; 4583 unsigned short snum; 4584 u32 sid, node_perm; 4585 4586 /* 4587 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4588 * that validates multiple binding addresses. Because of this 4589 * need to check address->sa_family as it is possible to have 4590 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4591 */ 4592 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4593 return -EINVAL; 4594 family_sa = address->sa_family; 4595 switch (family_sa) { 4596 case AF_UNSPEC: 4597 case AF_INET: 4598 if (addrlen < sizeof(struct sockaddr_in)) 4599 return -EINVAL; 4600 addr4 = (struct sockaddr_in *)address; 4601 if (family_sa == AF_UNSPEC) { 4602 /* see __inet_bind(), we only want to allow 4603 * AF_UNSPEC if the address is INADDR_ANY 4604 */ 4605 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4606 goto err_af; 4607 family_sa = AF_INET; 4608 } 4609 snum = ntohs(addr4->sin_port); 4610 addrp = (char *)&addr4->sin_addr.s_addr; 4611 break; 4612 case AF_INET6: 4613 if (addrlen < SIN6_LEN_RFC2133) 4614 return -EINVAL; 4615 addr6 = (struct sockaddr_in6 *)address; 4616 snum = ntohs(addr6->sin6_port); 4617 addrp = (char *)&addr6->sin6_addr.s6_addr; 4618 break; 4619 default: 4620 goto err_af; 4621 } 4622 4623 ad.type = LSM_AUDIT_DATA_NET; 4624 ad.u.net = &net; 4625 ad.u.net->sport = htons(snum); 4626 ad.u.net->family = family_sa; 4627 4628 if (snum) { 4629 int low, high; 4630 4631 inet_get_local_port_range(sock_net(sk), &low, &high); 4632 4633 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4634 snum < low || snum > high) { 4635 err = sel_netport_sid(sk->sk_protocol, 4636 snum, &sid); 4637 if (err) 4638 goto out; 4639 err = avc_has_perm(&selinux_state, 4640 sksec->sid, sid, 4641 sksec->sclass, 4642 SOCKET__NAME_BIND, &ad); 4643 if (err) 4644 goto out; 4645 } 4646 } 4647 4648 switch (sksec->sclass) { 4649 case SECCLASS_TCP_SOCKET: 4650 node_perm = TCP_SOCKET__NODE_BIND; 4651 break; 4652 4653 case SECCLASS_UDP_SOCKET: 4654 node_perm = UDP_SOCKET__NODE_BIND; 4655 break; 4656 4657 case SECCLASS_DCCP_SOCKET: 4658 node_perm = DCCP_SOCKET__NODE_BIND; 4659 break; 4660 4661 case SECCLASS_SCTP_SOCKET: 4662 node_perm = SCTP_SOCKET__NODE_BIND; 4663 break; 4664 4665 default: 4666 node_perm = RAWIP_SOCKET__NODE_BIND; 4667 break; 4668 } 4669 4670 err = sel_netnode_sid(addrp, family_sa, &sid); 4671 if (err) 4672 goto out; 4673 4674 if (family_sa == AF_INET) 4675 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4676 else 4677 ad.u.net->v6info.saddr = addr6->sin6_addr; 4678 4679 err = avc_has_perm(&selinux_state, 4680 sksec->sid, sid, 4681 sksec->sclass, node_perm, &ad); 4682 if (err) 4683 goto out; 4684 } 4685 out: 4686 return err; 4687 err_af: 4688 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4689 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4690 return -EINVAL; 4691 return -EAFNOSUPPORT; 4692 } 4693 4694 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4695 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4696 */ 4697 static int selinux_socket_connect_helper(struct socket *sock, 4698 struct sockaddr *address, int addrlen) 4699 { 4700 struct sock *sk = sock->sk; 4701 struct sk_security_struct *sksec = sk->sk_security; 4702 int err; 4703 4704 err = sock_has_perm(sk, SOCKET__CONNECT); 4705 if (err) 4706 return err; 4707 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4708 return -EINVAL; 4709 4710 /* connect(AF_UNSPEC) has special handling, as it is a documented 4711 * way to disconnect the socket 4712 */ 4713 if (address->sa_family == AF_UNSPEC) 4714 return 0; 4715 4716 /* 4717 * If a TCP, DCCP or SCTP socket, check name_connect permission 4718 * for the port. 4719 */ 4720 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4721 sksec->sclass == SECCLASS_DCCP_SOCKET || 4722 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4723 struct common_audit_data ad; 4724 struct lsm_network_audit net = {0,}; 4725 struct sockaddr_in *addr4 = NULL; 4726 struct sockaddr_in6 *addr6 = NULL; 4727 unsigned short snum; 4728 u32 sid, perm; 4729 4730 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4731 * that validates multiple connect addresses. Because of this 4732 * need to check address->sa_family as it is possible to have 4733 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4734 */ 4735 switch (address->sa_family) { 4736 case AF_INET: 4737 addr4 = (struct sockaddr_in *)address; 4738 if (addrlen < sizeof(struct sockaddr_in)) 4739 return -EINVAL; 4740 snum = ntohs(addr4->sin_port); 4741 break; 4742 case AF_INET6: 4743 addr6 = (struct sockaddr_in6 *)address; 4744 if (addrlen < SIN6_LEN_RFC2133) 4745 return -EINVAL; 4746 snum = ntohs(addr6->sin6_port); 4747 break; 4748 default: 4749 /* Note that SCTP services expect -EINVAL, whereas 4750 * others expect -EAFNOSUPPORT. 4751 */ 4752 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4753 return -EINVAL; 4754 else 4755 return -EAFNOSUPPORT; 4756 } 4757 4758 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4759 if (err) 4760 return err; 4761 4762 switch (sksec->sclass) { 4763 case SECCLASS_TCP_SOCKET: 4764 perm = TCP_SOCKET__NAME_CONNECT; 4765 break; 4766 case SECCLASS_DCCP_SOCKET: 4767 perm = DCCP_SOCKET__NAME_CONNECT; 4768 break; 4769 case SECCLASS_SCTP_SOCKET: 4770 perm = SCTP_SOCKET__NAME_CONNECT; 4771 break; 4772 } 4773 4774 ad.type = LSM_AUDIT_DATA_NET; 4775 ad.u.net = &net; 4776 ad.u.net->dport = htons(snum); 4777 ad.u.net->family = address->sa_family; 4778 err = avc_has_perm(&selinux_state, 4779 sksec->sid, sid, sksec->sclass, perm, &ad); 4780 if (err) 4781 return err; 4782 } 4783 4784 return 0; 4785 } 4786 4787 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4788 static int selinux_socket_connect(struct socket *sock, 4789 struct sockaddr *address, int addrlen) 4790 { 4791 int err; 4792 struct sock *sk = sock->sk; 4793 4794 err = selinux_socket_connect_helper(sock, address, addrlen); 4795 if (err) 4796 return err; 4797 4798 return selinux_netlbl_socket_connect(sk, address); 4799 } 4800 4801 static int selinux_socket_listen(struct socket *sock, int backlog) 4802 { 4803 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4804 } 4805 4806 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4807 { 4808 int err; 4809 struct inode_security_struct *isec; 4810 struct inode_security_struct *newisec; 4811 u16 sclass; 4812 u32 sid; 4813 4814 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4815 if (err) 4816 return err; 4817 4818 isec = inode_security_novalidate(SOCK_INODE(sock)); 4819 spin_lock(&isec->lock); 4820 sclass = isec->sclass; 4821 sid = isec->sid; 4822 spin_unlock(&isec->lock); 4823 4824 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4825 newisec->sclass = sclass; 4826 newisec->sid = sid; 4827 newisec->initialized = LABEL_INITIALIZED; 4828 4829 return 0; 4830 } 4831 4832 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4833 int size) 4834 { 4835 return sock_has_perm(sock->sk, SOCKET__WRITE); 4836 } 4837 4838 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4839 int size, int flags) 4840 { 4841 return sock_has_perm(sock->sk, SOCKET__READ); 4842 } 4843 4844 static int selinux_socket_getsockname(struct socket *sock) 4845 { 4846 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4847 } 4848 4849 static int selinux_socket_getpeername(struct socket *sock) 4850 { 4851 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4852 } 4853 4854 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4855 { 4856 int err; 4857 4858 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4859 if (err) 4860 return err; 4861 4862 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4863 } 4864 4865 static int selinux_socket_getsockopt(struct socket *sock, int level, 4866 int optname) 4867 { 4868 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4869 } 4870 4871 static int selinux_socket_shutdown(struct socket *sock, int how) 4872 { 4873 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4874 } 4875 4876 static int selinux_socket_unix_stream_connect(struct sock *sock, 4877 struct sock *other, 4878 struct sock *newsk) 4879 { 4880 struct sk_security_struct *sksec_sock = sock->sk_security; 4881 struct sk_security_struct *sksec_other = other->sk_security; 4882 struct sk_security_struct *sksec_new = newsk->sk_security; 4883 struct common_audit_data ad; 4884 struct lsm_network_audit net = {0,}; 4885 int err; 4886 4887 ad.type = LSM_AUDIT_DATA_NET; 4888 ad.u.net = &net; 4889 ad.u.net->sk = other; 4890 4891 err = avc_has_perm(&selinux_state, 4892 sksec_sock->sid, sksec_other->sid, 4893 sksec_other->sclass, 4894 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4895 if (err) 4896 return err; 4897 4898 /* server child socket */ 4899 sksec_new->peer_sid = sksec_sock->sid; 4900 err = security_sid_mls_copy(&selinux_state, sksec_other->sid, 4901 sksec_sock->sid, &sksec_new->sid); 4902 if (err) 4903 return err; 4904 4905 /* connecting socket */ 4906 sksec_sock->peer_sid = sksec_new->sid; 4907 4908 return 0; 4909 } 4910 4911 static int selinux_socket_unix_may_send(struct socket *sock, 4912 struct socket *other) 4913 { 4914 struct sk_security_struct *ssec = sock->sk->sk_security; 4915 struct sk_security_struct *osec = other->sk->sk_security; 4916 struct common_audit_data ad; 4917 struct lsm_network_audit net = {0,}; 4918 4919 ad.type = LSM_AUDIT_DATA_NET; 4920 ad.u.net = &net; 4921 ad.u.net->sk = other->sk; 4922 4923 return avc_has_perm(&selinux_state, 4924 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4925 &ad); 4926 } 4927 4928 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4929 char *addrp, u16 family, u32 peer_sid, 4930 struct common_audit_data *ad) 4931 { 4932 int err; 4933 u32 if_sid; 4934 u32 node_sid; 4935 4936 err = sel_netif_sid(ns, ifindex, &if_sid); 4937 if (err) 4938 return err; 4939 err = avc_has_perm(&selinux_state, 4940 peer_sid, if_sid, 4941 SECCLASS_NETIF, NETIF__INGRESS, ad); 4942 if (err) 4943 return err; 4944 4945 err = sel_netnode_sid(addrp, family, &node_sid); 4946 if (err) 4947 return err; 4948 return avc_has_perm(&selinux_state, 4949 peer_sid, node_sid, 4950 SECCLASS_NODE, NODE__RECVFROM, ad); 4951 } 4952 4953 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4954 u16 family) 4955 { 4956 int err = 0; 4957 struct sk_security_struct *sksec = sk->sk_security; 4958 u32 sk_sid = sksec->sid; 4959 struct common_audit_data ad; 4960 struct lsm_network_audit net = {0,}; 4961 char *addrp; 4962 4963 ad.type = LSM_AUDIT_DATA_NET; 4964 ad.u.net = &net; 4965 ad.u.net->netif = skb->skb_iif; 4966 ad.u.net->family = family; 4967 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4968 if (err) 4969 return err; 4970 4971 if (selinux_secmark_enabled()) { 4972 err = avc_has_perm(&selinux_state, 4973 sk_sid, skb->secmark, SECCLASS_PACKET, 4974 PACKET__RECV, &ad); 4975 if (err) 4976 return err; 4977 } 4978 4979 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4980 if (err) 4981 return err; 4982 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4983 4984 return err; 4985 } 4986 4987 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4988 { 4989 int err; 4990 struct sk_security_struct *sksec = sk->sk_security; 4991 u16 family = sk->sk_family; 4992 u32 sk_sid = sksec->sid; 4993 struct common_audit_data ad; 4994 struct lsm_network_audit net = {0,}; 4995 char *addrp; 4996 u8 secmark_active; 4997 u8 peerlbl_active; 4998 4999 if (family != PF_INET && family != PF_INET6) 5000 return 0; 5001 5002 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5003 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5004 family = PF_INET; 5005 5006 /* If any sort of compatibility mode is enabled then handoff processing 5007 * to the selinux_sock_rcv_skb_compat() function to deal with the 5008 * special handling. We do this in an attempt to keep this function 5009 * as fast and as clean as possible. */ 5010 if (!selinux_policycap_netpeer()) 5011 return selinux_sock_rcv_skb_compat(sk, skb, family); 5012 5013 secmark_active = selinux_secmark_enabled(); 5014 peerlbl_active = selinux_peerlbl_enabled(); 5015 if (!secmark_active && !peerlbl_active) 5016 return 0; 5017 5018 ad.type = LSM_AUDIT_DATA_NET; 5019 ad.u.net = &net; 5020 ad.u.net->netif = skb->skb_iif; 5021 ad.u.net->family = family; 5022 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5023 if (err) 5024 return err; 5025 5026 if (peerlbl_active) { 5027 u32 peer_sid; 5028 5029 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5030 if (err) 5031 return err; 5032 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5033 addrp, family, peer_sid, &ad); 5034 if (err) { 5035 selinux_netlbl_err(skb, family, err, 0); 5036 return err; 5037 } 5038 err = avc_has_perm(&selinux_state, 5039 sk_sid, peer_sid, SECCLASS_PEER, 5040 PEER__RECV, &ad); 5041 if (err) { 5042 selinux_netlbl_err(skb, family, err, 0); 5043 return err; 5044 } 5045 } 5046 5047 if (secmark_active) { 5048 err = avc_has_perm(&selinux_state, 5049 sk_sid, skb->secmark, SECCLASS_PACKET, 5050 PACKET__RECV, &ad); 5051 if (err) 5052 return err; 5053 } 5054 5055 return err; 5056 } 5057 5058 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 5059 int __user *optlen, unsigned len) 5060 { 5061 int err = 0; 5062 char *scontext; 5063 u32 scontext_len; 5064 struct sk_security_struct *sksec = sock->sk->sk_security; 5065 u32 peer_sid = SECSID_NULL; 5066 5067 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5068 sksec->sclass == SECCLASS_TCP_SOCKET || 5069 sksec->sclass == SECCLASS_SCTP_SOCKET) 5070 peer_sid = sksec->peer_sid; 5071 if (peer_sid == SECSID_NULL) 5072 return -ENOPROTOOPT; 5073 5074 err = security_sid_to_context(&selinux_state, peer_sid, &scontext, 5075 &scontext_len); 5076 if (err) 5077 return err; 5078 5079 if (scontext_len > len) { 5080 err = -ERANGE; 5081 goto out_len; 5082 } 5083 5084 if (copy_to_user(optval, scontext, scontext_len)) 5085 err = -EFAULT; 5086 5087 out_len: 5088 if (put_user(scontext_len, optlen)) 5089 err = -EFAULT; 5090 kfree(scontext); 5091 return err; 5092 } 5093 5094 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5095 { 5096 u32 peer_secid = SECSID_NULL; 5097 u16 family; 5098 struct inode_security_struct *isec; 5099 5100 if (skb && skb->protocol == htons(ETH_P_IP)) 5101 family = PF_INET; 5102 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5103 family = PF_INET6; 5104 else if (sock) 5105 family = sock->sk->sk_family; 5106 else 5107 goto out; 5108 5109 if (sock && family == PF_UNIX) { 5110 isec = inode_security_novalidate(SOCK_INODE(sock)); 5111 peer_secid = isec->sid; 5112 } else if (skb) 5113 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5114 5115 out: 5116 *secid = peer_secid; 5117 if (peer_secid == SECSID_NULL) 5118 return -EINVAL; 5119 return 0; 5120 } 5121 5122 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5123 { 5124 struct sk_security_struct *sksec; 5125 5126 sksec = kzalloc(sizeof(*sksec), priority); 5127 if (!sksec) 5128 return -ENOMEM; 5129 5130 sksec->peer_sid = SECINITSID_UNLABELED; 5131 sksec->sid = SECINITSID_UNLABELED; 5132 sksec->sclass = SECCLASS_SOCKET; 5133 selinux_netlbl_sk_security_reset(sksec); 5134 sk->sk_security = sksec; 5135 5136 return 0; 5137 } 5138 5139 static void selinux_sk_free_security(struct sock *sk) 5140 { 5141 struct sk_security_struct *sksec = sk->sk_security; 5142 5143 sk->sk_security = NULL; 5144 selinux_netlbl_sk_security_free(sksec); 5145 kfree(sksec); 5146 } 5147 5148 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5149 { 5150 struct sk_security_struct *sksec = sk->sk_security; 5151 struct sk_security_struct *newsksec = newsk->sk_security; 5152 5153 newsksec->sid = sksec->sid; 5154 newsksec->peer_sid = sksec->peer_sid; 5155 newsksec->sclass = sksec->sclass; 5156 5157 selinux_netlbl_sk_security_reset(newsksec); 5158 } 5159 5160 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 5161 { 5162 if (!sk) 5163 *secid = SECINITSID_ANY_SOCKET; 5164 else { 5165 struct sk_security_struct *sksec = sk->sk_security; 5166 5167 *secid = sksec->sid; 5168 } 5169 } 5170 5171 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5172 { 5173 struct inode_security_struct *isec = 5174 inode_security_novalidate(SOCK_INODE(parent)); 5175 struct sk_security_struct *sksec = sk->sk_security; 5176 5177 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5178 sk->sk_family == PF_UNIX) 5179 isec->sid = sksec->sid; 5180 sksec->sclass = isec->sclass; 5181 } 5182 5183 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming 5184 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association 5185 * already present). 5186 */ 5187 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep, 5188 struct sk_buff *skb) 5189 { 5190 struct sk_security_struct *sksec = ep->base.sk->sk_security; 5191 struct common_audit_data ad; 5192 struct lsm_network_audit net = {0,}; 5193 u8 peerlbl_active; 5194 u32 peer_sid = SECINITSID_UNLABELED; 5195 u32 conn_sid; 5196 int err = 0; 5197 5198 if (!selinux_policycap_extsockclass()) 5199 return 0; 5200 5201 peerlbl_active = selinux_peerlbl_enabled(); 5202 5203 if (peerlbl_active) { 5204 /* This will return peer_sid = SECSID_NULL if there are 5205 * no peer labels, see security_net_peersid_resolve(). 5206 */ 5207 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family, 5208 &peer_sid); 5209 if (err) 5210 return err; 5211 5212 if (peer_sid == SECSID_NULL) 5213 peer_sid = SECINITSID_UNLABELED; 5214 } 5215 5216 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5217 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5218 5219 /* Here as first association on socket. As the peer SID 5220 * was allowed by peer recv (and the netif/node checks), 5221 * then it is approved by policy and used as the primary 5222 * peer SID for getpeercon(3). 5223 */ 5224 sksec->peer_sid = peer_sid; 5225 } else if (sksec->peer_sid != peer_sid) { 5226 /* Other association peer SIDs are checked to enforce 5227 * consistency among the peer SIDs. 5228 */ 5229 ad.type = LSM_AUDIT_DATA_NET; 5230 ad.u.net = &net; 5231 ad.u.net->sk = ep->base.sk; 5232 err = avc_has_perm(&selinux_state, 5233 sksec->peer_sid, peer_sid, sksec->sclass, 5234 SCTP_SOCKET__ASSOCIATION, &ad); 5235 if (err) 5236 return err; 5237 } 5238 5239 /* Compute the MLS component for the connection and store 5240 * the information in ep. This will be used by SCTP TCP type 5241 * sockets and peeled off connections as they cause a new 5242 * socket to be generated. selinux_sctp_sk_clone() will then 5243 * plug this into the new socket. 5244 */ 5245 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid); 5246 if (err) 5247 return err; 5248 5249 ep->secid = conn_sid; 5250 ep->peer_secid = peer_sid; 5251 5252 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5253 return selinux_netlbl_sctp_assoc_request(ep, skb); 5254 } 5255 5256 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5257 * based on their @optname. 5258 */ 5259 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5260 struct sockaddr *address, 5261 int addrlen) 5262 { 5263 int len, err = 0, walk_size = 0; 5264 void *addr_buf; 5265 struct sockaddr *addr; 5266 struct socket *sock; 5267 5268 if (!selinux_policycap_extsockclass()) 5269 return 0; 5270 5271 /* Process one or more addresses that may be IPv4 or IPv6 */ 5272 sock = sk->sk_socket; 5273 addr_buf = address; 5274 5275 while (walk_size < addrlen) { 5276 if (walk_size + sizeof(sa_family_t) > addrlen) 5277 return -EINVAL; 5278 5279 addr = addr_buf; 5280 switch (addr->sa_family) { 5281 case AF_UNSPEC: 5282 case AF_INET: 5283 len = sizeof(struct sockaddr_in); 5284 break; 5285 case AF_INET6: 5286 len = sizeof(struct sockaddr_in6); 5287 break; 5288 default: 5289 return -EINVAL; 5290 } 5291 5292 if (walk_size + len > addrlen) 5293 return -EINVAL; 5294 5295 err = -EINVAL; 5296 switch (optname) { 5297 /* Bind checks */ 5298 case SCTP_PRIMARY_ADDR: 5299 case SCTP_SET_PEER_PRIMARY_ADDR: 5300 case SCTP_SOCKOPT_BINDX_ADD: 5301 err = selinux_socket_bind(sock, addr, len); 5302 break; 5303 /* Connect checks */ 5304 case SCTP_SOCKOPT_CONNECTX: 5305 case SCTP_PARAM_SET_PRIMARY: 5306 case SCTP_PARAM_ADD_IP: 5307 case SCTP_SENDMSG_CONNECT: 5308 err = selinux_socket_connect_helper(sock, addr, len); 5309 if (err) 5310 return err; 5311 5312 /* As selinux_sctp_bind_connect() is called by the 5313 * SCTP protocol layer, the socket is already locked, 5314 * therefore selinux_netlbl_socket_connect_locked() 5315 * is called here. The situations handled are: 5316 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5317 * whenever a new IP address is added or when a new 5318 * primary address is selected. 5319 * Note that an SCTP connect(2) call happens before 5320 * the SCTP protocol layer and is handled via 5321 * selinux_socket_connect(). 5322 */ 5323 err = selinux_netlbl_socket_connect_locked(sk, addr); 5324 break; 5325 } 5326 5327 if (err) 5328 return err; 5329 5330 addr_buf += len; 5331 walk_size += len; 5332 } 5333 5334 return 0; 5335 } 5336 5337 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5338 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk, 5339 struct sock *newsk) 5340 { 5341 struct sk_security_struct *sksec = sk->sk_security; 5342 struct sk_security_struct *newsksec = newsk->sk_security; 5343 5344 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5345 * the non-sctp clone version. 5346 */ 5347 if (!selinux_policycap_extsockclass()) 5348 return selinux_sk_clone_security(sk, newsk); 5349 5350 newsksec->sid = ep->secid; 5351 newsksec->peer_sid = ep->peer_secid; 5352 newsksec->sclass = sksec->sclass; 5353 selinux_netlbl_sctp_sk_clone(sk, newsk); 5354 } 5355 5356 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 5357 struct request_sock *req) 5358 { 5359 struct sk_security_struct *sksec = sk->sk_security; 5360 int err; 5361 u16 family = req->rsk_ops->family; 5362 u32 connsid; 5363 u32 peersid; 5364 5365 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5366 if (err) 5367 return err; 5368 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5369 if (err) 5370 return err; 5371 req->secid = connsid; 5372 req->peer_secid = peersid; 5373 5374 return selinux_netlbl_inet_conn_request(req, family); 5375 } 5376 5377 static void selinux_inet_csk_clone(struct sock *newsk, 5378 const struct request_sock *req) 5379 { 5380 struct sk_security_struct *newsksec = newsk->sk_security; 5381 5382 newsksec->sid = req->secid; 5383 newsksec->peer_sid = req->peer_secid; 5384 /* NOTE: Ideally, we should also get the isec->sid for the 5385 new socket in sync, but we don't have the isec available yet. 5386 So we will wait until sock_graft to do it, by which 5387 time it will have been created and available. */ 5388 5389 /* We don't need to take any sort of lock here as we are the only 5390 * thread with access to newsksec */ 5391 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5392 } 5393 5394 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5395 { 5396 u16 family = sk->sk_family; 5397 struct sk_security_struct *sksec = sk->sk_security; 5398 5399 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5400 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5401 family = PF_INET; 5402 5403 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5404 } 5405 5406 static int selinux_secmark_relabel_packet(u32 sid) 5407 { 5408 const struct task_security_struct *__tsec; 5409 u32 tsid; 5410 5411 __tsec = selinux_cred(current_cred()); 5412 tsid = __tsec->sid; 5413 5414 return avc_has_perm(&selinux_state, 5415 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5416 NULL); 5417 } 5418 5419 static void selinux_secmark_refcount_inc(void) 5420 { 5421 atomic_inc(&selinux_secmark_refcount); 5422 } 5423 5424 static void selinux_secmark_refcount_dec(void) 5425 { 5426 atomic_dec(&selinux_secmark_refcount); 5427 } 5428 5429 static void selinux_req_classify_flow(const struct request_sock *req, 5430 struct flowi *fl) 5431 { 5432 fl->flowi_secid = req->secid; 5433 } 5434 5435 static int selinux_tun_dev_alloc_security(void **security) 5436 { 5437 struct tun_security_struct *tunsec; 5438 5439 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5440 if (!tunsec) 5441 return -ENOMEM; 5442 tunsec->sid = current_sid(); 5443 5444 *security = tunsec; 5445 return 0; 5446 } 5447 5448 static void selinux_tun_dev_free_security(void *security) 5449 { 5450 kfree(security); 5451 } 5452 5453 static int selinux_tun_dev_create(void) 5454 { 5455 u32 sid = current_sid(); 5456 5457 /* we aren't taking into account the "sockcreate" SID since the socket 5458 * that is being created here is not a socket in the traditional sense, 5459 * instead it is a private sock, accessible only to the kernel, and 5460 * representing a wide range of network traffic spanning multiple 5461 * connections unlike traditional sockets - check the TUN driver to 5462 * get a better understanding of why this socket is special */ 5463 5464 return avc_has_perm(&selinux_state, 5465 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5466 NULL); 5467 } 5468 5469 static int selinux_tun_dev_attach_queue(void *security) 5470 { 5471 struct tun_security_struct *tunsec = security; 5472 5473 return avc_has_perm(&selinux_state, 5474 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5475 TUN_SOCKET__ATTACH_QUEUE, NULL); 5476 } 5477 5478 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5479 { 5480 struct tun_security_struct *tunsec = security; 5481 struct sk_security_struct *sksec = sk->sk_security; 5482 5483 /* we don't currently perform any NetLabel based labeling here and it 5484 * isn't clear that we would want to do so anyway; while we could apply 5485 * labeling without the support of the TUN user the resulting labeled 5486 * traffic from the other end of the connection would almost certainly 5487 * cause confusion to the TUN user that had no idea network labeling 5488 * protocols were being used */ 5489 5490 sksec->sid = tunsec->sid; 5491 sksec->sclass = SECCLASS_TUN_SOCKET; 5492 5493 return 0; 5494 } 5495 5496 static int selinux_tun_dev_open(void *security) 5497 { 5498 struct tun_security_struct *tunsec = security; 5499 u32 sid = current_sid(); 5500 int err; 5501 5502 err = avc_has_perm(&selinux_state, 5503 sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5504 TUN_SOCKET__RELABELFROM, NULL); 5505 if (err) 5506 return err; 5507 err = avc_has_perm(&selinux_state, 5508 sid, sid, SECCLASS_TUN_SOCKET, 5509 TUN_SOCKET__RELABELTO, NULL); 5510 if (err) 5511 return err; 5512 tunsec->sid = sid; 5513 5514 return 0; 5515 } 5516 5517 #ifdef CONFIG_NETFILTER 5518 5519 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5520 const struct net_device *indev, 5521 u16 family) 5522 { 5523 int err; 5524 char *addrp; 5525 u32 peer_sid; 5526 struct common_audit_data ad; 5527 struct lsm_network_audit net = {0,}; 5528 u8 secmark_active; 5529 u8 netlbl_active; 5530 u8 peerlbl_active; 5531 5532 if (!selinux_policycap_netpeer()) 5533 return NF_ACCEPT; 5534 5535 secmark_active = selinux_secmark_enabled(); 5536 netlbl_active = netlbl_enabled(); 5537 peerlbl_active = selinux_peerlbl_enabled(); 5538 if (!secmark_active && !peerlbl_active) 5539 return NF_ACCEPT; 5540 5541 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5542 return NF_DROP; 5543 5544 ad.type = LSM_AUDIT_DATA_NET; 5545 ad.u.net = &net; 5546 ad.u.net->netif = indev->ifindex; 5547 ad.u.net->family = family; 5548 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5549 return NF_DROP; 5550 5551 if (peerlbl_active) { 5552 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5553 addrp, family, peer_sid, &ad); 5554 if (err) { 5555 selinux_netlbl_err(skb, family, err, 1); 5556 return NF_DROP; 5557 } 5558 } 5559 5560 if (secmark_active) 5561 if (avc_has_perm(&selinux_state, 5562 peer_sid, skb->secmark, 5563 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5564 return NF_DROP; 5565 5566 if (netlbl_active) 5567 /* we do this in the FORWARD path and not the POST_ROUTING 5568 * path because we want to make sure we apply the necessary 5569 * labeling before IPsec is applied so we can leverage AH 5570 * protection */ 5571 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5572 return NF_DROP; 5573 5574 return NF_ACCEPT; 5575 } 5576 5577 static unsigned int selinux_ipv4_forward(void *priv, 5578 struct sk_buff *skb, 5579 const struct nf_hook_state *state) 5580 { 5581 return selinux_ip_forward(skb, state->in, PF_INET); 5582 } 5583 5584 #if IS_ENABLED(CONFIG_IPV6) 5585 static unsigned int selinux_ipv6_forward(void *priv, 5586 struct sk_buff *skb, 5587 const struct nf_hook_state *state) 5588 { 5589 return selinux_ip_forward(skb, state->in, PF_INET6); 5590 } 5591 #endif /* IPV6 */ 5592 5593 static unsigned int selinux_ip_output(struct sk_buff *skb, 5594 u16 family) 5595 { 5596 struct sock *sk; 5597 u32 sid; 5598 5599 if (!netlbl_enabled()) 5600 return NF_ACCEPT; 5601 5602 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5603 * because we want to make sure we apply the necessary labeling 5604 * before IPsec is applied so we can leverage AH protection */ 5605 sk = skb->sk; 5606 if (sk) { 5607 struct sk_security_struct *sksec; 5608 5609 if (sk_listener(sk)) 5610 /* if the socket is the listening state then this 5611 * packet is a SYN-ACK packet which means it needs to 5612 * be labeled based on the connection/request_sock and 5613 * not the parent socket. unfortunately, we can't 5614 * lookup the request_sock yet as it isn't queued on 5615 * the parent socket until after the SYN-ACK is sent. 5616 * the "solution" is to simply pass the packet as-is 5617 * as any IP option based labeling should be copied 5618 * from the initial connection request (in the IP 5619 * layer). it is far from ideal, but until we get a 5620 * security label in the packet itself this is the 5621 * best we can do. */ 5622 return NF_ACCEPT; 5623 5624 /* standard practice, label using the parent socket */ 5625 sksec = sk->sk_security; 5626 sid = sksec->sid; 5627 } else 5628 sid = SECINITSID_KERNEL; 5629 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5630 return NF_DROP; 5631 5632 return NF_ACCEPT; 5633 } 5634 5635 static unsigned int selinux_ipv4_output(void *priv, 5636 struct sk_buff *skb, 5637 const struct nf_hook_state *state) 5638 { 5639 return selinux_ip_output(skb, PF_INET); 5640 } 5641 5642 #if IS_ENABLED(CONFIG_IPV6) 5643 static unsigned int selinux_ipv6_output(void *priv, 5644 struct sk_buff *skb, 5645 const struct nf_hook_state *state) 5646 { 5647 return selinux_ip_output(skb, PF_INET6); 5648 } 5649 #endif /* IPV6 */ 5650 5651 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5652 int ifindex, 5653 u16 family) 5654 { 5655 struct sock *sk = skb_to_full_sk(skb); 5656 struct sk_security_struct *sksec; 5657 struct common_audit_data ad; 5658 struct lsm_network_audit net = {0,}; 5659 char *addrp; 5660 u8 proto; 5661 5662 if (sk == NULL) 5663 return NF_ACCEPT; 5664 sksec = sk->sk_security; 5665 5666 ad.type = LSM_AUDIT_DATA_NET; 5667 ad.u.net = &net; 5668 ad.u.net->netif = ifindex; 5669 ad.u.net->family = family; 5670 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5671 return NF_DROP; 5672 5673 if (selinux_secmark_enabled()) 5674 if (avc_has_perm(&selinux_state, 5675 sksec->sid, skb->secmark, 5676 SECCLASS_PACKET, PACKET__SEND, &ad)) 5677 return NF_DROP_ERR(-ECONNREFUSED); 5678 5679 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5680 return NF_DROP_ERR(-ECONNREFUSED); 5681 5682 return NF_ACCEPT; 5683 } 5684 5685 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5686 const struct net_device *outdev, 5687 u16 family) 5688 { 5689 u32 secmark_perm; 5690 u32 peer_sid; 5691 int ifindex = outdev->ifindex; 5692 struct sock *sk; 5693 struct common_audit_data ad; 5694 struct lsm_network_audit net = {0,}; 5695 char *addrp; 5696 u8 secmark_active; 5697 u8 peerlbl_active; 5698 5699 /* If any sort of compatibility mode is enabled then handoff processing 5700 * to the selinux_ip_postroute_compat() function to deal with the 5701 * special handling. We do this in an attempt to keep this function 5702 * as fast and as clean as possible. */ 5703 if (!selinux_policycap_netpeer()) 5704 return selinux_ip_postroute_compat(skb, ifindex, family); 5705 5706 secmark_active = selinux_secmark_enabled(); 5707 peerlbl_active = selinux_peerlbl_enabled(); 5708 if (!secmark_active && !peerlbl_active) 5709 return NF_ACCEPT; 5710 5711 sk = skb_to_full_sk(skb); 5712 5713 #ifdef CONFIG_XFRM 5714 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5715 * packet transformation so allow the packet to pass without any checks 5716 * since we'll have another chance to perform access control checks 5717 * when the packet is on it's final way out. 5718 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5719 * is NULL, in this case go ahead and apply access control. 5720 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5721 * TCP listening state we cannot wait until the XFRM processing 5722 * is done as we will miss out on the SA label if we do; 5723 * unfortunately, this means more work, but it is only once per 5724 * connection. */ 5725 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5726 !(sk && sk_listener(sk))) 5727 return NF_ACCEPT; 5728 #endif 5729 5730 if (sk == NULL) { 5731 /* Without an associated socket the packet is either coming 5732 * from the kernel or it is being forwarded; check the packet 5733 * to determine which and if the packet is being forwarded 5734 * query the packet directly to determine the security label. */ 5735 if (skb->skb_iif) { 5736 secmark_perm = PACKET__FORWARD_OUT; 5737 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5738 return NF_DROP; 5739 } else { 5740 secmark_perm = PACKET__SEND; 5741 peer_sid = SECINITSID_KERNEL; 5742 } 5743 } else if (sk_listener(sk)) { 5744 /* Locally generated packet but the associated socket is in the 5745 * listening state which means this is a SYN-ACK packet. In 5746 * this particular case the correct security label is assigned 5747 * to the connection/request_sock but unfortunately we can't 5748 * query the request_sock as it isn't queued on the parent 5749 * socket until after the SYN-ACK packet is sent; the only 5750 * viable choice is to regenerate the label like we do in 5751 * selinux_inet_conn_request(). See also selinux_ip_output() 5752 * for similar problems. */ 5753 u32 skb_sid; 5754 struct sk_security_struct *sksec; 5755 5756 sksec = sk->sk_security; 5757 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5758 return NF_DROP; 5759 /* At this point, if the returned skb peerlbl is SECSID_NULL 5760 * and the packet has been through at least one XFRM 5761 * transformation then we must be dealing with the "final" 5762 * form of labeled IPsec packet; since we've already applied 5763 * all of our access controls on this packet we can safely 5764 * pass the packet. */ 5765 if (skb_sid == SECSID_NULL) { 5766 switch (family) { 5767 case PF_INET: 5768 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5769 return NF_ACCEPT; 5770 break; 5771 case PF_INET6: 5772 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5773 return NF_ACCEPT; 5774 break; 5775 default: 5776 return NF_DROP_ERR(-ECONNREFUSED); 5777 } 5778 } 5779 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5780 return NF_DROP; 5781 secmark_perm = PACKET__SEND; 5782 } else { 5783 /* Locally generated packet, fetch the security label from the 5784 * associated socket. */ 5785 struct sk_security_struct *sksec = sk->sk_security; 5786 peer_sid = sksec->sid; 5787 secmark_perm = PACKET__SEND; 5788 } 5789 5790 ad.type = LSM_AUDIT_DATA_NET; 5791 ad.u.net = &net; 5792 ad.u.net->netif = ifindex; 5793 ad.u.net->family = family; 5794 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5795 return NF_DROP; 5796 5797 if (secmark_active) 5798 if (avc_has_perm(&selinux_state, 5799 peer_sid, skb->secmark, 5800 SECCLASS_PACKET, secmark_perm, &ad)) 5801 return NF_DROP_ERR(-ECONNREFUSED); 5802 5803 if (peerlbl_active) { 5804 u32 if_sid; 5805 u32 node_sid; 5806 5807 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5808 return NF_DROP; 5809 if (avc_has_perm(&selinux_state, 5810 peer_sid, if_sid, 5811 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5812 return NF_DROP_ERR(-ECONNREFUSED); 5813 5814 if (sel_netnode_sid(addrp, family, &node_sid)) 5815 return NF_DROP; 5816 if (avc_has_perm(&selinux_state, 5817 peer_sid, node_sid, 5818 SECCLASS_NODE, NODE__SENDTO, &ad)) 5819 return NF_DROP_ERR(-ECONNREFUSED); 5820 } 5821 5822 return NF_ACCEPT; 5823 } 5824 5825 static unsigned int selinux_ipv4_postroute(void *priv, 5826 struct sk_buff *skb, 5827 const struct nf_hook_state *state) 5828 { 5829 return selinux_ip_postroute(skb, state->out, PF_INET); 5830 } 5831 5832 #if IS_ENABLED(CONFIG_IPV6) 5833 static unsigned int selinux_ipv6_postroute(void *priv, 5834 struct sk_buff *skb, 5835 const struct nf_hook_state *state) 5836 { 5837 return selinux_ip_postroute(skb, state->out, PF_INET6); 5838 } 5839 #endif /* IPV6 */ 5840 5841 #endif /* CONFIG_NETFILTER */ 5842 5843 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5844 { 5845 int rc = 0; 5846 unsigned int msg_len; 5847 unsigned int data_len = skb->len; 5848 unsigned char *data = skb->data; 5849 struct nlmsghdr *nlh; 5850 struct sk_security_struct *sksec = sk->sk_security; 5851 u16 sclass = sksec->sclass; 5852 u32 perm; 5853 5854 while (data_len >= nlmsg_total_size(0)) { 5855 nlh = (struct nlmsghdr *)data; 5856 5857 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5858 * users which means we can't reject skb's with bogus 5859 * length fields; our solution is to follow what 5860 * netlink_rcv_skb() does and simply skip processing at 5861 * messages with length fields that are clearly junk 5862 */ 5863 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5864 return 0; 5865 5866 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5867 if (rc == 0) { 5868 rc = sock_has_perm(sk, perm); 5869 if (rc) 5870 return rc; 5871 } else if (rc == -EINVAL) { 5872 /* -EINVAL is a missing msg/perm mapping */ 5873 pr_warn_ratelimited("SELinux: unrecognized netlink" 5874 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5875 " pid=%d comm=%s\n", 5876 sk->sk_protocol, nlh->nlmsg_type, 5877 secclass_map[sclass - 1].name, 5878 task_pid_nr(current), current->comm); 5879 if (enforcing_enabled(&selinux_state) && 5880 !security_get_allow_unknown(&selinux_state)) 5881 return rc; 5882 rc = 0; 5883 } else if (rc == -ENOENT) { 5884 /* -ENOENT is a missing socket/class mapping, ignore */ 5885 rc = 0; 5886 } else { 5887 return rc; 5888 } 5889 5890 /* move to the next message after applying netlink padding */ 5891 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5892 if (msg_len >= data_len) 5893 return 0; 5894 data_len -= msg_len; 5895 data += msg_len; 5896 } 5897 5898 return rc; 5899 } 5900 5901 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5902 { 5903 isec->sclass = sclass; 5904 isec->sid = current_sid(); 5905 } 5906 5907 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5908 u32 perms) 5909 { 5910 struct ipc_security_struct *isec; 5911 struct common_audit_data ad; 5912 u32 sid = current_sid(); 5913 5914 isec = selinux_ipc(ipc_perms); 5915 5916 ad.type = LSM_AUDIT_DATA_IPC; 5917 ad.u.ipc_id = ipc_perms->key; 5918 5919 return avc_has_perm(&selinux_state, 5920 sid, isec->sid, isec->sclass, perms, &ad); 5921 } 5922 5923 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5924 { 5925 struct msg_security_struct *msec; 5926 5927 msec = selinux_msg_msg(msg); 5928 msec->sid = SECINITSID_UNLABELED; 5929 5930 return 0; 5931 } 5932 5933 /* message queue security operations */ 5934 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5935 { 5936 struct ipc_security_struct *isec; 5937 struct common_audit_data ad; 5938 u32 sid = current_sid(); 5939 int rc; 5940 5941 isec = selinux_ipc(msq); 5942 ipc_init_security(isec, SECCLASS_MSGQ); 5943 5944 ad.type = LSM_AUDIT_DATA_IPC; 5945 ad.u.ipc_id = msq->key; 5946 5947 rc = avc_has_perm(&selinux_state, 5948 sid, isec->sid, SECCLASS_MSGQ, 5949 MSGQ__CREATE, &ad); 5950 return rc; 5951 } 5952 5953 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 5954 { 5955 struct ipc_security_struct *isec; 5956 struct common_audit_data ad; 5957 u32 sid = current_sid(); 5958 5959 isec = selinux_ipc(msq); 5960 5961 ad.type = LSM_AUDIT_DATA_IPC; 5962 ad.u.ipc_id = msq->key; 5963 5964 return avc_has_perm(&selinux_state, 5965 sid, isec->sid, SECCLASS_MSGQ, 5966 MSGQ__ASSOCIATE, &ad); 5967 } 5968 5969 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 5970 { 5971 int err; 5972 int perms; 5973 5974 switch (cmd) { 5975 case IPC_INFO: 5976 case MSG_INFO: 5977 /* No specific object, just general system-wide information. */ 5978 return avc_has_perm(&selinux_state, 5979 current_sid(), SECINITSID_KERNEL, 5980 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 5981 case IPC_STAT: 5982 case MSG_STAT: 5983 case MSG_STAT_ANY: 5984 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 5985 break; 5986 case IPC_SET: 5987 perms = MSGQ__SETATTR; 5988 break; 5989 case IPC_RMID: 5990 perms = MSGQ__DESTROY; 5991 break; 5992 default: 5993 return 0; 5994 } 5995 5996 err = ipc_has_perm(msq, perms); 5997 return err; 5998 } 5999 6000 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6001 { 6002 struct ipc_security_struct *isec; 6003 struct msg_security_struct *msec; 6004 struct common_audit_data ad; 6005 u32 sid = current_sid(); 6006 int rc; 6007 6008 isec = selinux_ipc(msq); 6009 msec = selinux_msg_msg(msg); 6010 6011 /* 6012 * First time through, need to assign label to the message 6013 */ 6014 if (msec->sid == SECINITSID_UNLABELED) { 6015 /* 6016 * Compute new sid based on current process and 6017 * message queue this message will be stored in 6018 */ 6019 rc = security_transition_sid(&selinux_state, sid, isec->sid, 6020 SECCLASS_MSG, NULL, &msec->sid); 6021 if (rc) 6022 return rc; 6023 } 6024 6025 ad.type = LSM_AUDIT_DATA_IPC; 6026 ad.u.ipc_id = msq->key; 6027 6028 /* Can this process write to the queue? */ 6029 rc = avc_has_perm(&selinux_state, 6030 sid, isec->sid, SECCLASS_MSGQ, 6031 MSGQ__WRITE, &ad); 6032 if (!rc) 6033 /* Can this process send the message */ 6034 rc = avc_has_perm(&selinux_state, 6035 sid, msec->sid, SECCLASS_MSG, 6036 MSG__SEND, &ad); 6037 if (!rc) 6038 /* Can the message be put in the queue? */ 6039 rc = avc_has_perm(&selinux_state, 6040 msec->sid, isec->sid, SECCLASS_MSGQ, 6041 MSGQ__ENQUEUE, &ad); 6042 6043 return rc; 6044 } 6045 6046 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6047 struct task_struct *target, 6048 long type, int mode) 6049 { 6050 struct ipc_security_struct *isec; 6051 struct msg_security_struct *msec; 6052 struct common_audit_data ad; 6053 u32 sid = task_sid(target); 6054 int rc; 6055 6056 isec = selinux_ipc(msq); 6057 msec = selinux_msg_msg(msg); 6058 6059 ad.type = LSM_AUDIT_DATA_IPC; 6060 ad.u.ipc_id = msq->key; 6061 6062 rc = avc_has_perm(&selinux_state, 6063 sid, isec->sid, 6064 SECCLASS_MSGQ, MSGQ__READ, &ad); 6065 if (!rc) 6066 rc = avc_has_perm(&selinux_state, 6067 sid, msec->sid, 6068 SECCLASS_MSG, MSG__RECEIVE, &ad); 6069 return rc; 6070 } 6071 6072 /* Shared Memory security operations */ 6073 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6074 { 6075 struct ipc_security_struct *isec; 6076 struct common_audit_data ad; 6077 u32 sid = current_sid(); 6078 int rc; 6079 6080 isec = selinux_ipc(shp); 6081 ipc_init_security(isec, SECCLASS_SHM); 6082 6083 ad.type = LSM_AUDIT_DATA_IPC; 6084 ad.u.ipc_id = shp->key; 6085 6086 rc = avc_has_perm(&selinux_state, 6087 sid, isec->sid, SECCLASS_SHM, 6088 SHM__CREATE, &ad); 6089 return rc; 6090 } 6091 6092 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6093 { 6094 struct ipc_security_struct *isec; 6095 struct common_audit_data ad; 6096 u32 sid = current_sid(); 6097 6098 isec = selinux_ipc(shp); 6099 6100 ad.type = LSM_AUDIT_DATA_IPC; 6101 ad.u.ipc_id = shp->key; 6102 6103 return avc_has_perm(&selinux_state, 6104 sid, isec->sid, SECCLASS_SHM, 6105 SHM__ASSOCIATE, &ad); 6106 } 6107 6108 /* Note, at this point, shp is locked down */ 6109 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6110 { 6111 int perms; 6112 int err; 6113 6114 switch (cmd) { 6115 case IPC_INFO: 6116 case SHM_INFO: 6117 /* No specific object, just general system-wide information. */ 6118 return avc_has_perm(&selinux_state, 6119 current_sid(), SECINITSID_KERNEL, 6120 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6121 case IPC_STAT: 6122 case SHM_STAT: 6123 case SHM_STAT_ANY: 6124 perms = SHM__GETATTR | SHM__ASSOCIATE; 6125 break; 6126 case IPC_SET: 6127 perms = SHM__SETATTR; 6128 break; 6129 case SHM_LOCK: 6130 case SHM_UNLOCK: 6131 perms = SHM__LOCK; 6132 break; 6133 case IPC_RMID: 6134 perms = SHM__DESTROY; 6135 break; 6136 default: 6137 return 0; 6138 } 6139 6140 err = ipc_has_perm(shp, perms); 6141 return err; 6142 } 6143 6144 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6145 char __user *shmaddr, int shmflg) 6146 { 6147 u32 perms; 6148 6149 if (shmflg & SHM_RDONLY) 6150 perms = SHM__READ; 6151 else 6152 perms = SHM__READ | SHM__WRITE; 6153 6154 return ipc_has_perm(shp, perms); 6155 } 6156 6157 /* Semaphore security operations */ 6158 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6159 { 6160 struct ipc_security_struct *isec; 6161 struct common_audit_data ad; 6162 u32 sid = current_sid(); 6163 int rc; 6164 6165 isec = selinux_ipc(sma); 6166 ipc_init_security(isec, SECCLASS_SEM); 6167 6168 ad.type = LSM_AUDIT_DATA_IPC; 6169 ad.u.ipc_id = sma->key; 6170 6171 rc = avc_has_perm(&selinux_state, 6172 sid, isec->sid, SECCLASS_SEM, 6173 SEM__CREATE, &ad); 6174 return rc; 6175 } 6176 6177 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6178 { 6179 struct ipc_security_struct *isec; 6180 struct common_audit_data ad; 6181 u32 sid = current_sid(); 6182 6183 isec = selinux_ipc(sma); 6184 6185 ad.type = LSM_AUDIT_DATA_IPC; 6186 ad.u.ipc_id = sma->key; 6187 6188 return avc_has_perm(&selinux_state, 6189 sid, isec->sid, SECCLASS_SEM, 6190 SEM__ASSOCIATE, &ad); 6191 } 6192 6193 /* Note, at this point, sma is locked down */ 6194 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6195 { 6196 int err; 6197 u32 perms; 6198 6199 switch (cmd) { 6200 case IPC_INFO: 6201 case SEM_INFO: 6202 /* No specific object, just general system-wide information. */ 6203 return avc_has_perm(&selinux_state, 6204 current_sid(), SECINITSID_KERNEL, 6205 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6206 case GETPID: 6207 case GETNCNT: 6208 case GETZCNT: 6209 perms = SEM__GETATTR; 6210 break; 6211 case GETVAL: 6212 case GETALL: 6213 perms = SEM__READ; 6214 break; 6215 case SETVAL: 6216 case SETALL: 6217 perms = SEM__WRITE; 6218 break; 6219 case IPC_RMID: 6220 perms = SEM__DESTROY; 6221 break; 6222 case IPC_SET: 6223 perms = SEM__SETATTR; 6224 break; 6225 case IPC_STAT: 6226 case SEM_STAT: 6227 case SEM_STAT_ANY: 6228 perms = SEM__GETATTR | SEM__ASSOCIATE; 6229 break; 6230 default: 6231 return 0; 6232 } 6233 6234 err = ipc_has_perm(sma, perms); 6235 return err; 6236 } 6237 6238 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6239 struct sembuf *sops, unsigned nsops, int alter) 6240 { 6241 u32 perms; 6242 6243 if (alter) 6244 perms = SEM__READ | SEM__WRITE; 6245 else 6246 perms = SEM__READ; 6247 6248 return ipc_has_perm(sma, perms); 6249 } 6250 6251 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6252 { 6253 u32 av = 0; 6254 6255 av = 0; 6256 if (flag & S_IRUGO) 6257 av |= IPC__UNIX_READ; 6258 if (flag & S_IWUGO) 6259 av |= IPC__UNIX_WRITE; 6260 6261 if (av == 0) 6262 return 0; 6263 6264 return ipc_has_perm(ipcp, av); 6265 } 6266 6267 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6268 { 6269 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6270 *secid = isec->sid; 6271 } 6272 6273 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6274 { 6275 if (inode) 6276 inode_doinit_with_dentry(inode, dentry); 6277 } 6278 6279 static int selinux_getprocattr(struct task_struct *p, 6280 char *name, char **value) 6281 { 6282 const struct task_security_struct *__tsec; 6283 u32 sid; 6284 int error; 6285 unsigned len; 6286 6287 rcu_read_lock(); 6288 __tsec = selinux_cred(__task_cred(p)); 6289 6290 if (current != p) { 6291 error = avc_has_perm(&selinux_state, 6292 current_sid(), __tsec->sid, 6293 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6294 if (error) 6295 goto bad; 6296 } 6297 6298 if (!strcmp(name, "current")) 6299 sid = __tsec->sid; 6300 else if (!strcmp(name, "prev")) 6301 sid = __tsec->osid; 6302 else if (!strcmp(name, "exec")) 6303 sid = __tsec->exec_sid; 6304 else if (!strcmp(name, "fscreate")) 6305 sid = __tsec->create_sid; 6306 else if (!strcmp(name, "keycreate")) 6307 sid = __tsec->keycreate_sid; 6308 else if (!strcmp(name, "sockcreate")) 6309 sid = __tsec->sockcreate_sid; 6310 else { 6311 error = -EINVAL; 6312 goto bad; 6313 } 6314 rcu_read_unlock(); 6315 6316 if (!sid) 6317 return 0; 6318 6319 error = security_sid_to_context(&selinux_state, sid, value, &len); 6320 if (error) 6321 return error; 6322 return len; 6323 6324 bad: 6325 rcu_read_unlock(); 6326 return error; 6327 } 6328 6329 static int selinux_setprocattr(const char *name, void *value, size_t size) 6330 { 6331 struct task_security_struct *tsec; 6332 struct cred *new; 6333 u32 mysid = current_sid(), sid = 0, ptsid; 6334 int error; 6335 char *str = value; 6336 6337 /* 6338 * Basic control over ability to set these attributes at all. 6339 */ 6340 if (!strcmp(name, "exec")) 6341 error = avc_has_perm(&selinux_state, 6342 mysid, mysid, SECCLASS_PROCESS, 6343 PROCESS__SETEXEC, NULL); 6344 else if (!strcmp(name, "fscreate")) 6345 error = avc_has_perm(&selinux_state, 6346 mysid, mysid, SECCLASS_PROCESS, 6347 PROCESS__SETFSCREATE, NULL); 6348 else if (!strcmp(name, "keycreate")) 6349 error = avc_has_perm(&selinux_state, 6350 mysid, mysid, SECCLASS_PROCESS, 6351 PROCESS__SETKEYCREATE, NULL); 6352 else if (!strcmp(name, "sockcreate")) 6353 error = avc_has_perm(&selinux_state, 6354 mysid, mysid, SECCLASS_PROCESS, 6355 PROCESS__SETSOCKCREATE, NULL); 6356 else if (!strcmp(name, "current")) 6357 error = avc_has_perm(&selinux_state, 6358 mysid, mysid, SECCLASS_PROCESS, 6359 PROCESS__SETCURRENT, NULL); 6360 else 6361 error = -EINVAL; 6362 if (error) 6363 return error; 6364 6365 /* Obtain a SID for the context, if one was specified. */ 6366 if (size && str[0] && str[0] != '\n') { 6367 if (str[size-1] == '\n') { 6368 str[size-1] = 0; 6369 size--; 6370 } 6371 error = security_context_to_sid(&selinux_state, value, size, 6372 &sid, GFP_KERNEL); 6373 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6374 if (!has_cap_mac_admin(true)) { 6375 struct audit_buffer *ab; 6376 size_t audit_size; 6377 6378 /* We strip a nul only if it is at the end, otherwise the 6379 * context contains a nul and we should audit that */ 6380 if (str[size - 1] == '\0') 6381 audit_size = size - 1; 6382 else 6383 audit_size = size; 6384 ab = audit_log_start(audit_context(), 6385 GFP_ATOMIC, 6386 AUDIT_SELINUX_ERR); 6387 audit_log_format(ab, "op=fscreate invalid_context="); 6388 audit_log_n_untrustedstring(ab, value, audit_size); 6389 audit_log_end(ab); 6390 6391 return error; 6392 } 6393 error = security_context_to_sid_force( 6394 &selinux_state, 6395 value, size, &sid); 6396 } 6397 if (error) 6398 return error; 6399 } 6400 6401 new = prepare_creds(); 6402 if (!new) 6403 return -ENOMEM; 6404 6405 /* Permission checking based on the specified context is 6406 performed during the actual operation (execve, 6407 open/mkdir/...), when we know the full context of the 6408 operation. See selinux_bprm_creds_for_exec for the execve 6409 checks and may_create for the file creation checks. The 6410 operation will then fail if the context is not permitted. */ 6411 tsec = selinux_cred(new); 6412 if (!strcmp(name, "exec")) { 6413 tsec->exec_sid = sid; 6414 } else if (!strcmp(name, "fscreate")) { 6415 tsec->create_sid = sid; 6416 } else if (!strcmp(name, "keycreate")) { 6417 if (sid) { 6418 error = avc_has_perm(&selinux_state, mysid, sid, 6419 SECCLASS_KEY, KEY__CREATE, NULL); 6420 if (error) 6421 goto abort_change; 6422 } 6423 tsec->keycreate_sid = sid; 6424 } else if (!strcmp(name, "sockcreate")) { 6425 tsec->sockcreate_sid = sid; 6426 } else if (!strcmp(name, "current")) { 6427 error = -EINVAL; 6428 if (sid == 0) 6429 goto abort_change; 6430 6431 /* Only allow single threaded processes to change context */ 6432 error = -EPERM; 6433 if (!current_is_single_threaded()) { 6434 error = security_bounded_transition(&selinux_state, 6435 tsec->sid, sid); 6436 if (error) 6437 goto abort_change; 6438 } 6439 6440 /* Check permissions for the transition. */ 6441 error = avc_has_perm(&selinux_state, 6442 tsec->sid, sid, SECCLASS_PROCESS, 6443 PROCESS__DYNTRANSITION, NULL); 6444 if (error) 6445 goto abort_change; 6446 6447 /* Check for ptracing, and update the task SID if ok. 6448 Otherwise, leave SID unchanged and fail. */ 6449 ptsid = ptrace_parent_sid(); 6450 if (ptsid != 0) { 6451 error = avc_has_perm(&selinux_state, 6452 ptsid, sid, SECCLASS_PROCESS, 6453 PROCESS__PTRACE, NULL); 6454 if (error) 6455 goto abort_change; 6456 } 6457 6458 tsec->sid = sid; 6459 } else { 6460 error = -EINVAL; 6461 goto abort_change; 6462 } 6463 6464 commit_creds(new); 6465 return size; 6466 6467 abort_change: 6468 abort_creds(new); 6469 return error; 6470 } 6471 6472 static int selinux_ismaclabel(const char *name) 6473 { 6474 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6475 } 6476 6477 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6478 { 6479 return security_sid_to_context(&selinux_state, secid, 6480 secdata, seclen); 6481 } 6482 6483 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6484 { 6485 return security_context_to_sid(&selinux_state, secdata, seclen, 6486 secid, GFP_KERNEL); 6487 } 6488 6489 static void selinux_release_secctx(char *secdata, u32 seclen) 6490 { 6491 kfree(secdata); 6492 } 6493 6494 static void selinux_inode_invalidate_secctx(struct inode *inode) 6495 { 6496 struct inode_security_struct *isec = selinux_inode(inode); 6497 6498 spin_lock(&isec->lock); 6499 isec->initialized = LABEL_INVALID; 6500 spin_unlock(&isec->lock); 6501 } 6502 6503 /* 6504 * called with inode->i_mutex locked 6505 */ 6506 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6507 { 6508 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6509 ctx, ctxlen, 0); 6510 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6511 return rc == -EOPNOTSUPP ? 0 : rc; 6512 } 6513 6514 /* 6515 * called with inode->i_mutex locked 6516 */ 6517 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6518 { 6519 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 6520 } 6521 6522 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6523 { 6524 int len = 0; 6525 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 6526 ctx, true); 6527 if (len < 0) 6528 return len; 6529 *ctxlen = len; 6530 return 0; 6531 } 6532 #ifdef CONFIG_KEYS 6533 6534 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6535 unsigned long flags) 6536 { 6537 const struct task_security_struct *tsec; 6538 struct key_security_struct *ksec; 6539 6540 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6541 if (!ksec) 6542 return -ENOMEM; 6543 6544 tsec = selinux_cred(cred); 6545 if (tsec->keycreate_sid) 6546 ksec->sid = tsec->keycreate_sid; 6547 else 6548 ksec->sid = tsec->sid; 6549 6550 k->security = ksec; 6551 return 0; 6552 } 6553 6554 static void selinux_key_free(struct key *k) 6555 { 6556 struct key_security_struct *ksec = k->security; 6557 6558 k->security = NULL; 6559 kfree(ksec); 6560 } 6561 6562 static int selinux_key_permission(key_ref_t key_ref, 6563 const struct cred *cred, 6564 enum key_need_perm need_perm) 6565 { 6566 struct key *key; 6567 struct key_security_struct *ksec; 6568 u32 perm, sid; 6569 6570 switch (need_perm) { 6571 case KEY_NEED_VIEW: 6572 perm = KEY__VIEW; 6573 break; 6574 case KEY_NEED_READ: 6575 perm = KEY__READ; 6576 break; 6577 case KEY_NEED_WRITE: 6578 perm = KEY__WRITE; 6579 break; 6580 case KEY_NEED_SEARCH: 6581 perm = KEY__SEARCH; 6582 break; 6583 case KEY_NEED_LINK: 6584 perm = KEY__LINK; 6585 break; 6586 case KEY_NEED_SETATTR: 6587 perm = KEY__SETATTR; 6588 break; 6589 case KEY_NEED_UNLINK: 6590 case KEY_SYSADMIN_OVERRIDE: 6591 case KEY_AUTHTOKEN_OVERRIDE: 6592 case KEY_DEFER_PERM_CHECK: 6593 return 0; 6594 default: 6595 WARN_ON(1); 6596 return -EPERM; 6597 6598 } 6599 6600 sid = cred_sid(cred); 6601 key = key_ref_to_ptr(key_ref); 6602 ksec = key->security; 6603 6604 return avc_has_perm(&selinux_state, 6605 sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6606 } 6607 6608 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6609 { 6610 struct key_security_struct *ksec = key->security; 6611 char *context = NULL; 6612 unsigned len; 6613 int rc; 6614 6615 rc = security_sid_to_context(&selinux_state, ksec->sid, 6616 &context, &len); 6617 if (!rc) 6618 rc = len; 6619 *_buffer = context; 6620 return rc; 6621 } 6622 6623 #ifdef CONFIG_KEY_NOTIFICATIONS 6624 static int selinux_watch_key(struct key *key) 6625 { 6626 struct key_security_struct *ksec = key->security; 6627 u32 sid = current_sid(); 6628 6629 return avc_has_perm(&selinux_state, 6630 sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6631 } 6632 #endif 6633 #endif 6634 6635 #ifdef CONFIG_SECURITY_INFINIBAND 6636 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6637 { 6638 struct common_audit_data ad; 6639 int err; 6640 u32 sid = 0; 6641 struct ib_security_struct *sec = ib_sec; 6642 struct lsm_ibpkey_audit ibpkey; 6643 6644 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6645 if (err) 6646 return err; 6647 6648 ad.type = LSM_AUDIT_DATA_IBPKEY; 6649 ibpkey.subnet_prefix = subnet_prefix; 6650 ibpkey.pkey = pkey_val; 6651 ad.u.ibpkey = &ibpkey; 6652 return avc_has_perm(&selinux_state, 6653 sec->sid, sid, 6654 SECCLASS_INFINIBAND_PKEY, 6655 INFINIBAND_PKEY__ACCESS, &ad); 6656 } 6657 6658 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6659 u8 port_num) 6660 { 6661 struct common_audit_data ad; 6662 int err; 6663 u32 sid = 0; 6664 struct ib_security_struct *sec = ib_sec; 6665 struct lsm_ibendport_audit ibendport; 6666 6667 err = security_ib_endport_sid(&selinux_state, dev_name, port_num, 6668 &sid); 6669 6670 if (err) 6671 return err; 6672 6673 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6674 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name)); 6675 ibendport.port = port_num; 6676 ad.u.ibendport = &ibendport; 6677 return avc_has_perm(&selinux_state, 6678 sec->sid, sid, 6679 SECCLASS_INFINIBAND_ENDPORT, 6680 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6681 } 6682 6683 static int selinux_ib_alloc_security(void **ib_sec) 6684 { 6685 struct ib_security_struct *sec; 6686 6687 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6688 if (!sec) 6689 return -ENOMEM; 6690 sec->sid = current_sid(); 6691 6692 *ib_sec = sec; 6693 return 0; 6694 } 6695 6696 static void selinux_ib_free_security(void *ib_sec) 6697 { 6698 kfree(ib_sec); 6699 } 6700 #endif 6701 6702 #ifdef CONFIG_BPF_SYSCALL 6703 static int selinux_bpf(int cmd, union bpf_attr *attr, 6704 unsigned int size) 6705 { 6706 u32 sid = current_sid(); 6707 int ret; 6708 6709 switch (cmd) { 6710 case BPF_MAP_CREATE: 6711 ret = avc_has_perm(&selinux_state, 6712 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6713 NULL); 6714 break; 6715 case BPF_PROG_LOAD: 6716 ret = avc_has_perm(&selinux_state, 6717 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6718 NULL); 6719 break; 6720 default: 6721 ret = 0; 6722 break; 6723 } 6724 6725 return ret; 6726 } 6727 6728 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6729 { 6730 u32 av = 0; 6731 6732 if (fmode & FMODE_READ) 6733 av |= BPF__MAP_READ; 6734 if (fmode & FMODE_WRITE) 6735 av |= BPF__MAP_WRITE; 6736 return av; 6737 } 6738 6739 /* This function will check the file pass through unix socket or binder to see 6740 * if it is a bpf related object. And apply correspinding checks on the bpf 6741 * object based on the type. The bpf maps and programs, not like other files and 6742 * socket, are using a shared anonymous inode inside the kernel as their inode. 6743 * So checking that inode cannot identify if the process have privilege to 6744 * access the bpf object and that's why we have to add this additional check in 6745 * selinux_file_receive and selinux_binder_transfer_files. 6746 */ 6747 static int bpf_fd_pass(struct file *file, u32 sid) 6748 { 6749 struct bpf_security_struct *bpfsec; 6750 struct bpf_prog *prog; 6751 struct bpf_map *map; 6752 int ret; 6753 6754 if (file->f_op == &bpf_map_fops) { 6755 map = file->private_data; 6756 bpfsec = map->security; 6757 ret = avc_has_perm(&selinux_state, 6758 sid, bpfsec->sid, SECCLASS_BPF, 6759 bpf_map_fmode_to_av(file->f_mode), NULL); 6760 if (ret) 6761 return ret; 6762 } else if (file->f_op == &bpf_prog_fops) { 6763 prog = file->private_data; 6764 bpfsec = prog->aux->security; 6765 ret = avc_has_perm(&selinux_state, 6766 sid, bpfsec->sid, SECCLASS_BPF, 6767 BPF__PROG_RUN, NULL); 6768 if (ret) 6769 return ret; 6770 } 6771 return 0; 6772 } 6773 6774 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6775 { 6776 u32 sid = current_sid(); 6777 struct bpf_security_struct *bpfsec; 6778 6779 bpfsec = map->security; 6780 return avc_has_perm(&selinux_state, 6781 sid, bpfsec->sid, SECCLASS_BPF, 6782 bpf_map_fmode_to_av(fmode), NULL); 6783 } 6784 6785 static int selinux_bpf_prog(struct bpf_prog *prog) 6786 { 6787 u32 sid = current_sid(); 6788 struct bpf_security_struct *bpfsec; 6789 6790 bpfsec = prog->aux->security; 6791 return avc_has_perm(&selinux_state, 6792 sid, bpfsec->sid, SECCLASS_BPF, 6793 BPF__PROG_RUN, NULL); 6794 } 6795 6796 static int selinux_bpf_map_alloc(struct bpf_map *map) 6797 { 6798 struct bpf_security_struct *bpfsec; 6799 6800 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6801 if (!bpfsec) 6802 return -ENOMEM; 6803 6804 bpfsec->sid = current_sid(); 6805 map->security = bpfsec; 6806 6807 return 0; 6808 } 6809 6810 static void selinux_bpf_map_free(struct bpf_map *map) 6811 { 6812 struct bpf_security_struct *bpfsec = map->security; 6813 6814 map->security = NULL; 6815 kfree(bpfsec); 6816 } 6817 6818 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6819 { 6820 struct bpf_security_struct *bpfsec; 6821 6822 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6823 if (!bpfsec) 6824 return -ENOMEM; 6825 6826 bpfsec->sid = current_sid(); 6827 aux->security = bpfsec; 6828 6829 return 0; 6830 } 6831 6832 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6833 { 6834 struct bpf_security_struct *bpfsec = aux->security; 6835 6836 aux->security = NULL; 6837 kfree(bpfsec); 6838 } 6839 #endif 6840 6841 static int selinux_lockdown(enum lockdown_reason what) 6842 { 6843 struct common_audit_data ad; 6844 u32 sid = current_sid(); 6845 int invalid_reason = (what <= LOCKDOWN_NONE) || 6846 (what == LOCKDOWN_INTEGRITY_MAX) || 6847 (what >= LOCKDOWN_CONFIDENTIALITY_MAX); 6848 6849 if (WARN(invalid_reason, "Invalid lockdown reason")) { 6850 audit_log(audit_context(), 6851 GFP_ATOMIC, AUDIT_SELINUX_ERR, 6852 "lockdown_reason=invalid"); 6853 return -EINVAL; 6854 } 6855 6856 ad.type = LSM_AUDIT_DATA_LOCKDOWN; 6857 ad.u.reason = what; 6858 6859 if (what <= LOCKDOWN_INTEGRITY_MAX) 6860 return avc_has_perm(&selinux_state, 6861 sid, sid, SECCLASS_LOCKDOWN, 6862 LOCKDOWN__INTEGRITY, &ad); 6863 else 6864 return avc_has_perm(&selinux_state, 6865 sid, sid, SECCLASS_LOCKDOWN, 6866 LOCKDOWN__CONFIDENTIALITY, &ad); 6867 } 6868 6869 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = { 6870 .lbs_cred = sizeof(struct task_security_struct), 6871 .lbs_file = sizeof(struct file_security_struct), 6872 .lbs_inode = sizeof(struct inode_security_struct), 6873 .lbs_ipc = sizeof(struct ipc_security_struct), 6874 .lbs_msg_msg = sizeof(struct msg_security_struct), 6875 }; 6876 6877 #ifdef CONFIG_PERF_EVENTS 6878 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6879 { 6880 u32 requested, sid = current_sid(); 6881 6882 if (type == PERF_SECURITY_OPEN) 6883 requested = PERF_EVENT__OPEN; 6884 else if (type == PERF_SECURITY_CPU) 6885 requested = PERF_EVENT__CPU; 6886 else if (type == PERF_SECURITY_KERNEL) 6887 requested = PERF_EVENT__KERNEL; 6888 else if (type == PERF_SECURITY_TRACEPOINT) 6889 requested = PERF_EVENT__TRACEPOINT; 6890 else 6891 return -EINVAL; 6892 6893 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT, 6894 requested, NULL); 6895 } 6896 6897 static int selinux_perf_event_alloc(struct perf_event *event) 6898 { 6899 struct perf_event_security_struct *perfsec; 6900 6901 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6902 if (!perfsec) 6903 return -ENOMEM; 6904 6905 perfsec->sid = current_sid(); 6906 event->security = perfsec; 6907 6908 return 0; 6909 } 6910 6911 static void selinux_perf_event_free(struct perf_event *event) 6912 { 6913 struct perf_event_security_struct *perfsec = event->security; 6914 6915 event->security = NULL; 6916 kfree(perfsec); 6917 } 6918 6919 static int selinux_perf_event_read(struct perf_event *event) 6920 { 6921 struct perf_event_security_struct *perfsec = event->security; 6922 u32 sid = current_sid(); 6923 6924 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6925 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6926 } 6927 6928 static int selinux_perf_event_write(struct perf_event *event) 6929 { 6930 struct perf_event_security_struct *perfsec = event->security; 6931 u32 sid = current_sid(); 6932 6933 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6934 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6935 } 6936 #endif 6937 6938 /* 6939 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6940 * 1. any hooks that don't belong to (2.) or (3.) below, 6941 * 2. hooks that both access structures allocated by other hooks, and allocate 6942 * structures that can be later accessed by other hooks (mostly "cloning" 6943 * hooks), 6944 * 3. hooks that only allocate structures that can be later accessed by other 6945 * hooks ("allocating" hooks). 6946 * 6947 * Please follow block comment delimiters in the list to keep this order. 6948 * 6949 * This ordering is needed for SELinux runtime disable to work at least somewhat 6950 * safely. Breaking the ordering rules above might lead to NULL pointer derefs 6951 * when disabling SELinux at runtime. 6952 */ 6953 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { 6954 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6955 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6956 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6957 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6958 6959 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6960 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6961 LSM_HOOK_INIT(capget, selinux_capget), 6962 LSM_HOOK_INIT(capset, selinux_capset), 6963 LSM_HOOK_INIT(capable, selinux_capable), 6964 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6965 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6966 LSM_HOOK_INIT(syslog, selinux_syslog), 6967 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6968 6969 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6970 6971 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 6972 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6973 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6974 6975 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), 6976 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 6977 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6978 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6979 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6980 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6981 LSM_HOOK_INIT(sb_mount, selinux_mount), 6982 LSM_HOOK_INIT(sb_umount, selinux_umount), 6983 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6984 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6985 6986 LSM_HOOK_INIT(move_mount, selinux_move_mount), 6987 6988 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6989 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 6990 6991 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 6992 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 6993 LSM_HOOK_INIT(inode_create, selinux_inode_create), 6994 LSM_HOOK_INIT(inode_link, selinux_inode_link), 6995 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 6996 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 6997 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 6998 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 6999 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7000 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7001 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7002 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7003 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7004 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7005 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7006 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7007 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7008 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7009 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7010 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7011 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7012 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7013 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7014 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7015 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7016 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7017 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7018 7019 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7020 7021 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7022 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7023 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7024 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7025 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7026 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7027 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7028 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7029 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7030 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7031 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7032 7033 LSM_HOOK_INIT(file_open, selinux_file_open), 7034 7035 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7036 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7037 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7038 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7039 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7040 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7041 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7042 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7043 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7044 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7045 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7046 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7047 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), 7048 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7049 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7050 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7051 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7052 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7053 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7054 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7055 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7056 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7057 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7058 7059 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7060 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7061 7062 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7063 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7064 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7065 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7066 7067 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7068 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7069 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7070 7071 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7072 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7073 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7074 7075 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7076 7077 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7078 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7079 7080 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7081 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7082 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7083 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7084 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7085 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7086 7087 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7088 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7089 7090 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7091 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7092 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7093 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7094 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7095 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7096 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7097 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7098 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7099 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7100 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7101 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7102 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7103 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7104 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7105 LSM_HOOK_INIT(socket_getpeersec_stream, 7106 selinux_socket_getpeersec_stream), 7107 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7108 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7109 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7110 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7111 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7112 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7113 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7114 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7115 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7116 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7117 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7118 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7119 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7120 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7121 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7122 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7123 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7124 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7125 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7126 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7127 #ifdef CONFIG_SECURITY_INFINIBAND 7128 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7129 LSM_HOOK_INIT(ib_endport_manage_subnet, 7130 selinux_ib_endport_manage_subnet), 7131 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7132 #endif 7133 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7134 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7135 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7136 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7137 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7138 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7139 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7140 selinux_xfrm_state_pol_flow_match), 7141 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7142 #endif 7143 7144 #ifdef CONFIG_KEYS 7145 LSM_HOOK_INIT(key_free, selinux_key_free), 7146 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7147 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7148 #ifdef CONFIG_KEY_NOTIFICATIONS 7149 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7150 #endif 7151 #endif 7152 7153 #ifdef CONFIG_AUDIT 7154 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7155 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7156 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7157 #endif 7158 7159 #ifdef CONFIG_BPF_SYSCALL 7160 LSM_HOOK_INIT(bpf, selinux_bpf), 7161 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7162 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7163 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7164 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7165 #endif 7166 7167 #ifdef CONFIG_PERF_EVENTS 7168 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7169 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7170 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7171 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7172 #endif 7173 7174 LSM_HOOK_INIT(locked_down, selinux_lockdown), 7175 7176 /* 7177 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7178 */ 7179 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7180 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7181 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7182 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt), 7183 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7184 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7185 #endif 7186 7187 /* 7188 * PUT "ALLOCATING" HOOKS HERE 7189 */ 7190 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7191 LSM_HOOK_INIT(msg_queue_alloc_security, 7192 selinux_msg_queue_alloc_security), 7193 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7194 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7195 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7196 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7197 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7198 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7199 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7200 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7201 #ifdef CONFIG_SECURITY_INFINIBAND 7202 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7203 #endif 7204 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7205 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7206 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7207 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7208 selinux_xfrm_state_alloc_acquire), 7209 #endif 7210 #ifdef CONFIG_KEYS 7211 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7212 #endif 7213 #ifdef CONFIG_AUDIT 7214 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7215 #endif 7216 #ifdef CONFIG_BPF_SYSCALL 7217 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7218 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7219 #endif 7220 #ifdef CONFIG_PERF_EVENTS 7221 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7222 #endif 7223 }; 7224 7225 static __init int selinux_init(void) 7226 { 7227 pr_info("SELinux: Initializing.\n"); 7228 7229 memset(&selinux_state, 0, sizeof(selinux_state)); 7230 enforcing_set(&selinux_state, selinux_enforcing_boot); 7231 checkreqprot_set(&selinux_state, selinux_checkreqprot_boot); 7232 selinux_avc_init(&selinux_state.avc); 7233 mutex_init(&selinux_state.status_lock); 7234 mutex_init(&selinux_state.policy_mutex); 7235 7236 /* Set the security state for the initial task. */ 7237 cred_init_security(); 7238 7239 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7240 7241 avc_init(); 7242 7243 avtab_cache_init(); 7244 7245 ebitmap_cache_init(); 7246 7247 hashtab_cache_init(); 7248 7249 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7250 7251 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7252 panic("SELinux: Unable to register AVC netcache callback\n"); 7253 7254 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7255 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7256 7257 if (selinux_enforcing_boot) 7258 pr_debug("SELinux: Starting in enforcing mode\n"); 7259 else 7260 pr_debug("SELinux: Starting in permissive mode\n"); 7261 7262 fs_validate_description("selinux", selinux_fs_parameters); 7263 7264 return 0; 7265 } 7266 7267 static void delayed_superblock_init(struct super_block *sb, void *unused) 7268 { 7269 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7270 } 7271 7272 void selinux_complete_init(void) 7273 { 7274 pr_debug("SELinux: Completing initialization.\n"); 7275 7276 /* Set up any superblocks initialized prior to the policy load. */ 7277 pr_debug("SELinux: Setting up existing superblocks.\n"); 7278 iterate_supers(delayed_superblock_init, NULL); 7279 } 7280 7281 /* SELinux requires early initialization in order to label 7282 all processes and objects when they are created. */ 7283 DEFINE_LSM(selinux) = { 7284 .name = "selinux", 7285 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7286 .enabled = &selinux_enabled_boot, 7287 .blobs = &selinux_blob_sizes, 7288 .init = selinux_init, 7289 }; 7290 7291 #if defined(CONFIG_NETFILTER) 7292 7293 static const struct nf_hook_ops selinux_nf_ops[] = { 7294 { 7295 .hook = selinux_ipv4_postroute, 7296 .pf = NFPROTO_IPV4, 7297 .hooknum = NF_INET_POST_ROUTING, 7298 .priority = NF_IP_PRI_SELINUX_LAST, 7299 }, 7300 { 7301 .hook = selinux_ipv4_forward, 7302 .pf = NFPROTO_IPV4, 7303 .hooknum = NF_INET_FORWARD, 7304 .priority = NF_IP_PRI_SELINUX_FIRST, 7305 }, 7306 { 7307 .hook = selinux_ipv4_output, 7308 .pf = NFPROTO_IPV4, 7309 .hooknum = NF_INET_LOCAL_OUT, 7310 .priority = NF_IP_PRI_SELINUX_FIRST, 7311 }, 7312 #if IS_ENABLED(CONFIG_IPV6) 7313 { 7314 .hook = selinux_ipv6_postroute, 7315 .pf = NFPROTO_IPV6, 7316 .hooknum = NF_INET_POST_ROUTING, 7317 .priority = NF_IP6_PRI_SELINUX_LAST, 7318 }, 7319 { 7320 .hook = selinux_ipv6_forward, 7321 .pf = NFPROTO_IPV6, 7322 .hooknum = NF_INET_FORWARD, 7323 .priority = NF_IP6_PRI_SELINUX_FIRST, 7324 }, 7325 { 7326 .hook = selinux_ipv6_output, 7327 .pf = NFPROTO_IPV6, 7328 .hooknum = NF_INET_LOCAL_OUT, 7329 .priority = NF_IP6_PRI_SELINUX_FIRST, 7330 }, 7331 #endif /* IPV6 */ 7332 }; 7333 7334 static int __net_init selinux_nf_register(struct net *net) 7335 { 7336 return nf_register_net_hooks(net, selinux_nf_ops, 7337 ARRAY_SIZE(selinux_nf_ops)); 7338 } 7339 7340 static void __net_exit selinux_nf_unregister(struct net *net) 7341 { 7342 nf_unregister_net_hooks(net, selinux_nf_ops, 7343 ARRAY_SIZE(selinux_nf_ops)); 7344 } 7345 7346 static struct pernet_operations selinux_net_ops = { 7347 .init = selinux_nf_register, 7348 .exit = selinux_nf_unregister, 7349 }; 7350 7351 static int __init selinux_nf_ip_init(void) 7352 { 7353 int err; 7354 7355 if (!selinux_enabled_boot) 7356 return 0; 7357 7358 pr_debug("SELinux: Registering netfilter hooks\n"); 7359 7360 err = register_pernet_subsys(&selinux_net_ops); 7361 if (err) 7362 panic("SELinux: register_pernet_subsys: error %d\n", err); 7363 7364 return 0; 7365 } 7366 __initcall(selinux_nf_ip_init); 7367 7368 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7369 static void selinux_nf_ip_exit(void) 7370 { 7371 pr_debug("SELinux: Unregistering netfilter hooks\n"); 7372 7373 unregister_pernet_subsys(&selinux_net_ops); 7374 } 7375 #endif 7376 7377 #else /* CONFIG_NETFILTER */ 7378 7379 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7380 #define selinux_nf_ip_exit() 7381 #endif 7382 7383 #endif /* CONFIG_NETFILTER */ 7384 7385 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7386 int selinux_disable(struct selinux_state *state) 7387 { 7388 if (selinux_initialized(state)) { 7389 /* Not permitted after initial policy load. */ 7390 return -EINVAL; 7391 } 7392 7393 if (selinux_disabled(state)) { 7394 /* Only do this once. */ 7395 return -EINVAL; 7396 } 7397 7398 selinux_mark_disabled(state); 7399 7400 pr_info("SELinux: Disabled at runtime.\n"); 7401 7402 /* 7403 * Unregister netfilter hooks. 7404 * Must be done before security_delete_hooks() to avoid breaking 7405 * runtime disable. 7406 */ 7407 selinux_nf_ip_exit(); 7408 7409 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 7410 7411 /* Try to destroy the avc node cache */ 7412 avc_disable(); 7413 7414 /* Unregister selinuxfs. */ 7415 exit_sel_fs(); 7416 7417 return 0; 7418 } 7419 #endif 7420