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/kernel_read_file.h> 28 #include <linux/tracehook.h> 29 #include <linux/errno.h> 30 #include <linux/sched/signal.h> 31 #include <linux/sched/task.h> 32 #include <linux/lsm_hooks.h> 33 #include <linux/xattr.h> 34 #include <linux/capability.h> 35 #include <linux/unistd.h> 36 #include <linux/mm.h> 37 #include <linux/mman.h> 38 #include <linux/slab.h> 39 #include <linux/pagemap.h> 40 #include <linux/proc_fs.h> 41 #include <linux/swap.h> 42 #include <linux/spinlock.h> 43 #include <linux/syscalls.h> 44 #include <linux/dcache.h> 45 #include <linux/file.h> 46 #include <linux/fdtable.h> 47 #include <linux/namei.h> 48 #include <linux/mount.h> 49 #include <linux/fs_context.h> 50 #include <linux/fs_parser.h> 51 #include <linux/netfilter_ipv4.h> 52 #include <linux/netfilter_ipv6.h> 53 #include <linux/tty.h> 54 #include <net/icmp.h> 55 #include <net/ip.h> /* for local_port_range[] */ 56 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 57 #include <net/inet_connection_sock.h> 58 #include <net/net_namespace.h> 59 #include <net/netlabel.h> 60 #include <linux/uaccess.h> 61 #include <asm/ioctls.h> 62 #include <linux/atomic.h> 63 #include <linux/bitops.h> 64 #include <linux/interrupt.h> 65 #include <linux/netdevice.h> /* for network interface checks */ 66 #include <net/netlink.h> 67 #include <linux/tcp.h> 68 #include <linux/udp.h> 69 #include <linux/dccp.h> 70 #include <linux/sctp.h> 71 #include <net/sctp/structs.h> 72 #include <linux/quota.h> 73 #include <linux/un.h> /* for Unix socket types */ 74 #include <net/af_unix.h> /* for Unix socket types */ 75 #include <linux/parser.h> 76 #include <linux/nfs_mount.h> 77 #include <net/ipv6.h> 78 #include <linux/hugetlb.h> 79 #include <linux/personality.h> 80 #include <linux/audit.h> 81 #include <linux/string.h> 82 #include <linux/mutex.h> 83 #include <linux/posix-timers.h> 84 #include <linux/syslog.h> 85 #include <linux/user_namespace.h> 86 #include <linux/export.h> 87 #include <linux/msg.h> 88 #include <linux/shm.h> 89 #include <linux/bpf.h> 90 #include <linux/kernfs.h> 91 #include <linux/stringhash.h> /* for hashlen_string() */ 92 #include <uapi/linux/mount.h> 93 #include <linux/fsnotify.h> 94 #include <linux/fanotify.h> 95 96 #include "avc.h" 97 #include "objsec.h" 98 #include "netif.h" 99 #include "netnode.h" 100 #include "netport.h" 101 #include "ibpkey.h" 102 #include "xfrm.h" 103 #include "netlabel.h" 104 #include "audit.h" 105 #include "avc_ss.h" 106 107 struct selinux_state selinux_state; 108 109 /* SECMARK reference count */ 110 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 111 112 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 113 static int selinux_enforcing_boot __initdata; 114 115 static int __init enforcing_setup(char *str) 116 { 117 unsigned long enforcing; 118 if (!kstrtoul(str, 0, &enforcing)) 119 selinux_enforcing_boot = enforcing ? 1 : 0; 120 return 1; 121 } 122 __setup("enforcing=", enforcing_setup); 123 #else 124 #define selinux_enforcing_boot 1 125 #endif 126 127 int selinux_enabled_boot __initdata = 1; 128 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 129 static int __init selinux_enabled_setup(char *str) 130 { 131 unsigned long enabled; 132 if (!kstrtoul(str, 0, &enabled)) 133 selinux_enabled_boot = enabled ? 1 : 0; 134 return 1; 135 } 136 __setup("selinux=", selinux_enabled_setup); 137 #endif 138 139 static unsigned int selinux_checkreqprot_boot = 140 CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 141 142 static int __init checkreqprot_setup(char *str) 143 { 144 unsigned long checkreqprot; 145 146 if (!kstrtoul(str, 0, &checkreqprot)) { 147 selinux_checkreqprot_boot = checkreqprot ? 1 : 0; 148 if (checkreqprot) 149 pr_warn("SELinux: checkreqprot set to 1 via kernel parameter. This is deprecated and will be rejected in a future kernel release.\n"); 150 } 151 return 1; 152 } 153 __setup("checkreqprot=", checkreqprot_setup); 154 155 /** 156 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 157 * 158 * Description: 159 * This function checks the SECMARK reference counter to see if any SECMARK 160 * targets are currently configured, if the reference counter is greater than 161 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 162 * enabled, false (0) if SECMARK is disabled. If the always_check_network 163 * policy capability is enabled, SECMARK is always considered enabled. 164 * 165 */ 166 static int selinux_secmark_enabled(void) 167 { 168 return (selinux_policycap_alwaysnetwork() || 169 atomic_read(&selinux_secmark_refcount)); 170 } 171 172 /** 173 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 174 * 175 * Description: 176 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 177 * (1) if any are enabled or false (0) if neither are enabled. If the 178 * always_check_network policy capability is enabled, peer labeling 179 * is always considered enabled. 180 * 181 */ 182 static int selinux_peerlbl_enabled(void) 183 { 184 return (selinux_policycap_alwaysnetwork() || 185 netlbl_enabled() || selinux_xfrm_enabled()); 186 } 187 188 static int selinux_netcache_avc_callback(u32 event) 189 { 190 if (event == AVC_CALLBACK_RESET) { 191 sel_netif_flush(); 192 sel_netnode_flush(); 193 sel_netport_flush(); 194 synchronize_net(); 195 } 196 return 0; 197 } 198 199 static int selinux_lsm_notifier_avc_callback(u32 event) 200 { 201 if (event == AVC_CALLBACK_RESET) { 202 sel_ib_pkey_flush(); 203 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 204 } 205 206 return 0; 207 } 208 209 /* 210 * initialise the security for the init task 211 */ 212 static void cred_init_security(void) 213 { 214 struct cred *cred = (struct cred *) current->real_cred; 215 struct task_security_struct *tsec; 216 217 tsec = selinux_cred(cred); 218 tsec->osid = tsec->sid = SECINITSID_KERNEL; 219 } 220 221 /* 222 * get the security ID of a set of credentials 223 */ 224 static inline u32 cred_sid(const struct cred *cred) 225 { 226 const struct task_security_struct *tsec; 227 228 tsec = selinux_cred(cred); 229 return tsec->sid; 230 } 231 232 /* 233 * get the objective security ID of a task 234 */ 235 static inline u32 task_sid(const struct task_struct *task) 236 { 237 u32 sid; 238 239 rcu_read_lock(); 240 sid = cred_sid(__task_cred(task)); 241 rcu_read_unlock(); 242 return sid; 243 } 244 245 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 246 247 /* 248 * Try reloading inode security labels that have been marked as invalid. The 249 * @may_sleep parameter indicates when sleeping and thus reloading labels is 250 * allowed; when set to false, returns -ECHILD when the label is 251 * invalid. The @dentry parameter should be set to a dentry of the inode. 252 */ 253 static int __inode_security_revalidate(struct inode *inode, 254 struct dentry *dentry, 255 bool may_sleep) 256 { 257 struct inode_security_struct *isec = selinux_inode(inode); 258 259 might_sleep_if(may_sleep); 260 261 if (selinux_initialized(&selinux_state) && 262 isec->initialized != LABEL_INITIALIZED) { 263 if (!may_sleep) 264 return -ECHILD; 265 266 /* 267 * Try reloading the inode security label. This will fail if 268 * @opt_dentry is NULL and no dentry for this inode can be 269 * found; in that case, continue using the old label. 270 */ 271 inode_doinit_with_dentry(inode, dentry); 272 } 273 return 0; 274 } 275 276 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 277 { 278 return selinux_inode(inode); 279 } 280 281 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 282 { 283 int error; 284 285 error = __inode_security_revalidate(inode, NULL, !rcu); 286 if (error) 287 return ERR_PTR(error); 288 return selinux_inode(inode); 289 } 290 291 /* 292 * Get the security label of an inode. 293 */ 294 static struct inode_security_struct *inode_security(struct inode *inode) 295 { 296 __inode_security_revalidate(inode, NULL, true); 297 return selinux_inode(inode); 298 } 299 300 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 301 { 302 struct inode *inode = d_backing_inode(dentry); 303 304 return selinux_inode(inode); 305 } 306 307 /* 308 * Get the security label of a dentry's backing inode. 309 */ 310 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 311 { 312 struct inode *inode = d_backing_inode(dentry); 313 314 __inode_security_revalidate(inode, dentry, true); 315 return selinux_inode(inode); 316 } 317 318 static void inode_free_security(struct inode *inode) 319 { 320 struct inode_security_struct *isec = selinux_inode(inode); 321 struct superblock_security_struct *sbsec; 322 323 if (!isec) 324 return; 325 sbsec = inode->i_sb->s_security; 326 /* 327 * As not all inode security structures are in a list, we check for 328 * empty list outside of the lock to make sure that we won't waste 329 * time taking a lock doing nothing. 330 * 331 * The list_del_init() function can be safely called more than once. 332 * It should not be possible for this function to be called with 333 * concurrent list_add(), but for better safety against future changes 334 * in the code, we use list_empty_careful() here. 335 */ 336 if (!list_empty_careful(&isec->list)) { 337 spin_lock(&sbsec->isec_lock); 338 list_del_init(&isec->list); 339 spin_unlock(&sbsec->isec_lock); 340 } 341 } 342 343 static void superblock_free_security(struct super_block *sb) 344 { 345 struct superblock_security_struct *sbsec = sb->s_security; 346 sb->s_security = NULL; 347 kfree(sbsec); 348 } 349 350 struct selinux_mnt_opts { 351 const char *fscontext, *context, *rootcontext, *defcontext; 352 }; 353 354 static void selinux_free_mnt_opts(void *mnt_opts) 355 { 356 struct selinux_mnt_opts *opts = mnt_opts; 357 kfree(opts->fscontext); 358 kfree(opts->context); 359 kfree(opts->rootcontext); 360 kfree(opts->defcontext); 361 kfree(opts); 362 } 363 364 enum { 365 Opt_error = -1, 366 Opt_context = 0, 367 Opt_defcontext = 1, 368 Opt_fscontext = 2, 369 Opt_rootcontext = 3, 370 Opt_seclabel = 4, 371 }; 372 373 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 374 static struct { 375 const char *name; 376 int len; 377 int opt; 378 bool has_arg; 379 } tokens[] = { 380 A(context, true), 381 A(fscontext, true), 382 A(defcontext, true), 383 A(rootcontext, true), 384 A(seclabel, false), 385 }; 386 #undef A 387 388 static int match_opt_prefix(char *s, int l, char **arg) 389 { 390 int i; 391 392 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 393 size_t len = tokens[i].len; 394 if (len > l || memcmp(s, tokens[i].name, len)) 395 continue; 396 if (tokens[i].has_arg) { 397 if (len == l || s[len] != '=') 398 continue; 399 *arg = s + len + 1; 400 } else if (len != l) 401 continue; 402 return tokens[i].opt; 403 } 404 return Opt_error; 405 } 406 407 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 408 409 static int may_context_mount_sb_relabel(u32 sid, 410 struct superblock_security_struct *sbsec, 411 const struct cred *cred) 412 { 413 const struct task_security_struct *tsec = selinux_cred(cred); 414 int rc; 415 416 rc = avc_has_perm(&selinux_state, 417 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 418 FILESYSTEM__RELABELFROM, NULL); 419 if (rc) 420 return rc; 421 422 rc = avc_has_perm(&selinux_state, 423 tsec->sid, sid, SECCLASS_FILESYSTEM, 424 FILESYSTEM__RELABELTO, NULL); 425 return rc; 426 } 427 428 static int may_context_mount_inode_relabel(u32 sid, 429 struct superblock_security_struct *sbsec, 430 const struct cred *cred) 431 { 432 const struct task_security_struct *tsec = selinux_cred(cred); 433 int rc; 434 rc = avc_has_perm(&selinux_state, 435 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 436 FILESYSTEM__RELABELFROM, NULL); 437 if (rc) 438 return rc; 439 440 rc = avc_has_perm(&selinux_state, 441 sid, sbsec->sid, SECCLASS_FILESYSTEM, 442 FILESYSTEM__ASSOCIATE, NULL); 443 return rc; 444 } 445 446 static int selinux_is_genfs_special_handling(struct super_block *sb) 447 { 448 /* Special handling. Genfs but also in-core setxattr handler */ 449 return !strcmp(sb->s_type->name, "sysfs") || 450 !strcmp(sb->s_type->name, "pstore") || 451 !strcmp(sb->s_type->name, "debugfs") || 452 !strcmp(sb->s_type->name, "tracefs") || 453 !strcmp(sb->s_type->name, "rootfs") || 454 (selinux_policycap_cgroupseclabel() && 455 (!strcmp(sb->s_type->name, "cgroup") || 456 !strcmp(sb->s_type->name, "cgroup2"))); 457 } 458 459 static int selinux_is_sblabel_mnt(struct super_block *sb) 460 { 461 struct superblock_security_struct *sbsec = sb->s_security; 462 463 /* 464 * IMPORTANT: Double-check logic in this function when adding a new 465 * SECURITY_FS_USE_* definition! 466 */ 467 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 468 469 switch (sbsec->behavior) { 470 case SECURITY_FS_USE_XATTR: 471 case SECURITY_FS_USE_TRANS: 472 case SECURITY_FS_USE_TASK: 473 case SECURITY_FS_USE_NATIVE: 474 return 1; 475 476 case SECURITY_FS_USE_GENFS: 477 return selinux_is_genfs_special_handling(sb); 478 479 /* Never allow relabeling on context mounts */ 480 case SECURITY_FS_USE_MNTPOINT: 481 case SECURITY_FS_USE_NONE: 482 default: 483 return 0; 484 } 485 } 486 487 static int sb_finish_set_opts(struct super_block *sb) 488 { 489 struct superblock_security_struct *sbsec = sb->s_security; 490 struct dentry *root = sb->s_root; 491 struct inode *root_inode = d_backing_inode(root); 492 int rc = 0; 493 494 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 495 /* Make sure that the xattr handler exists and that no 496 error other than -ENODATA is returned by getxattr on 497 the root directory. -ENODATA is ok, as this may be 498 the first boot of the SELinux kernel before we have 499 assigned xattr values to the filesystem. */ 500 if (!(root_inode->i_opflags & IOP_XATTR)) { 501 pr_warn("SELinux: (dev %s, type %s) has no " 502 "xattr support\n", sb->s_id, sb->s_type->name); 503 rc = -EOPNOTSUPP; 504 goto out; 505 } 506 507 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 508 if (rc < 0 && rc != -ENODATA) { 509 if (rc == -EOPNOTSUPP) 510 pr_warn("SELinux: (dev %s, type " 511 "%s) has no security xattr handler\n", 512 sb->s_id, sb->s_type->name); 513 else 514 pr_warn("SELinux: (dev %s, type " 515 "%s) getxattr errno %d\n", sb->s_id, 516 sb->s_type->name, -rc); 517 goto out; 518 } 519 } 520 521 sbsec->flags |= SE_SBINITIALIZED; 522 523 /* 524 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 525 * leave the flag untouched because sb_clone_mnt_opts might be handing 526 * us a superblock that needs the flag to be cleared. 527 */ 528 if (selinux_is_sblabel_mnt(sb)) 529 sbsec->flags |= SBLABEL_MNT; 530 else 531 sbsec->flags &= ~SBLABEL_MNT; 532 533 /* Initialize the root inode. */ 534 rc = inode_doinit_with_dentry(root_inode, root); 535 536 /* Initialize any other inodes associated with the superblock, e.g. 537 inodes created prior to initial policy load or inodes created 538 during get_sb by a pseudo filesystem that directly 539 populates itself. */ 540 spin_lock(&sbsec->isec_lock); 541 while (!list_empty(&sbsec->isec_head)) { 542 struct inode_security_struct *isec = 543 list_first_entry(&sbsec->isec_head, 544 struct inode_security_struct, list); 545 struct inode *inode = isec->inode; 546 list_del_init(&isec->list); 547 spin_unlock(&sbsec->isec_lock); 548 inode = igrab(inode); 549 if (inode) { 550 if (!IS_PRIVATE(inode)) 551 inode_doinit_with_dentry(inode, NULL); 552 iput(inode); 553 } 554 spin_lock(&sbsec->isec_lock); 555 } 556 spin_unlock(&sbsec->isec_lock); 557 out: 558 return rc; 559 } 560 561 static int bad_option(struct superblock_security_struct *sbsec, char flag, 562 u32 old_sid, u32 new_sid) 563 { 564 char mnt_flags = sbsec->flags & SE_MNTMASK; 565 566 /* check if the old mount command had the same options */ 567 if (sbsec->flags & SE_SBINITIALIZED) 568 if (!(sbsec->flags & flag) || 569 (old_sid != new_sid)) 570 return 1; 571 572 /* check if we were passed the same options twice, 573 * aka someone passed context=a,context=b 574 */ 575 if (!(sbsec->flags & SE_SBINITIALIZED)) 576 if (mnt_flags & flag) 577 return 1; 578 return 0; 579 } 580 581 static int parse_sid(struct super_block *sb, const char *s, u32 *sid) 582 { 583 int rc = security_context_str_to_sid(&selinux_state, s, 584 sid, GFP_KERNEL); 585 if (rc) 586 pr_warn("SELinux: security_context_str_to_sid" 587 "(%s) failed for (dev %s, type %s) errno=%d\n", 588 s, sb->s_id, sb->s_type->name, rc); 589 return rc; 590 } 591 592 /* 593 * Allow filesystems with binary mount data to explicitly set mount point 594 * labeling information. 595 */ 596 static int selinux_set_mnt_opts(struct super_block *sb, 597 void *mnt_opts, 598 unsigned long kern_flags, 599 unsigned long *set_kern_flags) 600 { 601 const struct cred *cred = current_cred(); 602 struct superblock_security_struct *sbsec = sb->s_security; 603 struct dentry *root = sb->s_root; 604 struct selinux_mnt_opts *opts = mnt_opts; 605 struct inode_security_struct *root_isec; 606 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 607 u32 defcontext_sid = 0; 608 int rc = 0; 609 610 mutex_lock(&sbsec->lock); 611 612 if (!selinux_initialized(&selinux_state)) { 613 if (!opts) { 614 /* Defer initialization until selinux_complete_init, 615 after the initial policy is loaded and the security 616 server is ready to handle calls. */ 617 goto out; 618 } 619 rc = -EINVAL; 620 pr_warn("SELinux: Unable to set superblock options " 621 "before the security server is initialized\n"); 622 goto out; 623 } 624 if (kern_flags && !set_kern_flags) { 625 /* Specifying internal flags without providing a place to 626 * place the results is not allowed */ 627 rc = -EINVAL; 628 goto out; 629 } 630 631 /* 632 * Binary mount data FS will come through this function twice. Once 633 * from an explicit call and once from the generic calls from the vfs. 634 * Since the generic VFS calls will not contain any security mount data 635 * we need to skip the double mount verification. 636 * 637 * This does open a hole in which we will not notice if the first 638 * mount using this sb set explict options and a second mount using 639 * this sb does not set any security options. (The first options 640 * will be used for both mounts) 641 */ 642 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 643 && !opts) 644 goto out; 645 646 root_isec = backing_inode_security_novalidate(root); 647 648 /* 649 * parse the mount options, check if they are valid sids. 650 * also check if someone is trying to mount the same sb more 651 * than once with different security options. 652 */ 653 if (opts) { 654 if (opts->fscontext) { 655 rc = parse_sid(sb, opts->fscontext, &fscontext_sid); 656 if (rc) 657 goto out; 658 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 659 fscontext_sid)) 660 goto out_double_mount; 661 sbsec->flags |= FSCONTEXT_MNT; 662 } 663 if (opts->context) { 664 rc = parse_sid(sb, opts->context, &context_sid); 665 if (rc) 666 goto out; 667 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 668 context_sid)) 669 goto out_double_mount; 670 sbsec->flags |= CONTEXT_MNT; 671 } 672 if (opts->rootcontext) { 673 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid); 674 if (rc) 675 goto out; 676 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 677 rootcontext_sid)) 678 goto out_double_mount; 679 sbsec->flags |= ROOTCONTEXT_MNT; 680 } 681 if (opts->defcontext) { 682 rc = parse_sid(sb, opts->defcontext, &defcontext_sid); 683 if (rc) 684 goto out; 685 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 686 defcontext_sid)) 687 goto out_double_mount; 688 sbsec->flags |= DEFCONTEXT_MNT; 689 } 690 } 691 692 if (sbsec->flags & SE_SBINITIALIZED) { 693 /* previously mounted with options, but not on this attempt? */ 694 if ((sbsec->flags & SE_MNTMASK) && !opts) 695 goto out_double_mount; 696 rc = 0; 697 goto out; 698 } 699 700 if (strcmp(sb->s_type->name, "proc") == 0) 701 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 702 703 if (!strcmp(sb->s_type->name, "debugfs") || 704 !strcmp(sb->s_type->name, "tracefs") || 705 !strcmp(sb->s_type->name, "binder") || 706 !strcmp(sb->s_type->name, "bpf") || 707 !strcmp(sb->s_type->name, "pstore")) 708 sbsec->flags |= SE_SBGENFS; 709 710 if (!strcmp(sb->s_type->name, "sysfs") || 711 !strcmp(sb->s_type->name, "cgroup") || 712 !strcmp(sb->s_type->name, "cgroup2")) 713 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 714 715 if (!sbsec->behavior) { 716 /* 717 * Determine the labeling behavior to use for this 718 * filesystem type. 719 */ 720 rc = security_fs_use(&selinux_state, sb); 721 if (rc) { 722 pr_warn("%s: security_fs_use(%s) returned %d\n", 723 __func__, sb->s_type->name, rc); 724 goto out; 725 } 726 } 727 728 /* 729 * If this is a user namespace mount and the filesystem type is not 730 * explicitly whitelisted, then no contexts are allowed on the command 731 * line and security labels must be ignored. 732 */ 733 if (sb->s_user_ns != &init_user_ns && 734 strcmp(sb->s_type->name, "tmpfs") && 735 strcmp(sb->s_type->name, "ramfs") && 736 strcmp(sb->s_type->name, "devpts")) { 737 if (context_sid || fscontext_sid || rootcontext_sid || 738 defcontext_sid) { 739 rc = -EACCES; 740 goto out; 741 } 742 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 743 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 744 rc = security_transition_sid(&selinux_state, 745 current_sid(), 746 current_sid(), 747 SECCLASS_FILE, NULL, 748 &sbsec->mntpoint_sid); 749 if (rc) 750 goto out; 751 } 752 goto out_set_opts; 753 } 754 755 /* sets the context of the superblock for the fs being mounted. */ 756 if (fscontext_sid) { 757 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 758 if (rc) 759 goto out; 760 761 sbsec->sid = fscontext_sid; 762 } 763 764 /* 765 * Switch to using mount point labeling behavior. 766 * sets the label used on all file below the mountpoint, and will set 767 * the superblock context if not already set. 768 */ 769 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 770 sbsec->behavior = SECURITY_FS_USE_NATIVE; 771 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 772 } 773 774 if (context_sid) { 775 if (!fscontext_sid) { 776 rc = may_context_mount_sb_relabel(context_sid, sbsec, 777 cred); 778 if (rc) 779 goto out; 780 sbsec->sid = context_sid; 781 } else { 782 rc = may_context_mount_inode_relabel(context_sid, sbsec, 783 cred); 784 if (rc) 785 goto out; 786 } 787 if (!rootcontext_sid) 788 rootcontext_sid = context_sid; 789 790 sbsec->mntpoint_sid = context_sid; 791 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 792 } 793 794 if (rootcontext_sid) { 795 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 796 cred); 797 if (rc) 798 goto out; 799 800 root_isec->sid = rootcontext_sid; 801 root_isec->initialized = LABEL_INITIALIZED; 802 } 803 804 if (defcontext_sid) { 805 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 806 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 807 rc = -EINVAL; 808 pr_warn("SELinux: defcontext option is " 809 "invalid for this filesystem type\n"); 810 goto out; 811 } 812 813 if (defcontext_sid != sbsec->def_sid) { 814 rc = may_context_mount_inode_relabel(defcontext_sid, 815 sbsec, cred); 816 if (rc) 817 goto out; 818 } 819 820 sbsec->def_sid = defcontext_sid; 821 } 822 823 out_set_opts: 824 rc = sb_finish_set_opts(sb); 825 out: 826 mutex_unlock(&sbsec->lock); 827 return rc; 828 out_double_mount: 829 rc = -EINVAL; 830 pr_warn("SELinux: mount invalid. Same superblock, different " 831 "security settings for (dev %s, type %s)\n", sb->s_id, 832 sb->s_type->name); 833 goto out; 834 } 835 836 static int selinux_cmp_sb_context(const struct super_block *oldsb, 837 const struct super_block *newsb) 838 { 839 struct superblock_security_struct *old = oldsb->s_security; 840 struct superblock_security_struct *new = newsb->s_security; 841 char oldflags = old->flags & SE_MNTMASK; 842 char newflags = new->flags & SE_MNTMASK; 843 844 if (oldflags != newflags) 845 goto mismatch; 846 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 847 goto mismatch; 848 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 849 goto mismatch; 850 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 851 goto mismatch; 852 if (oldflags & ROOTCONTEXT_MNT) { 853 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 854 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 855 if (oldroot->sid != newroot->sid) 856 goto mismatch; 857 } 858 return 0; 859 mismatch: 860 pr_warn("SELinux: mount invalid. Same superblock, " 861 "different security settings for (dev %s, " 862 "type %s)\n", newsb->s_id, newsb->s_type->name); 863 return -EBUSY; 864 } 865 866 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 867 struct super_block *newsb, 868 unsigned long kern_flags, 869 unsigned long *set_kern_flags) 870 { 871 int rc = 0; 872 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 873 struct superblock_security_struct *newsbsec = newsb->s_security; 874 875 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 876 int set_context = (oldsbsec->flags & CONTEXT_MNT); 877 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 878 879 /* 880 * if the parent was able to be mounted it clearly had no special lsm 881 * mount options. thus we can safely deal with this superblock later 882 */ 883 if (!selinux_initialized(&selinux_state)) 884 return 0; 885 886 /* 887 * Specifying internal flags without providing a place to 888 * place the results is not allowed. 889 */ 890 if (kern_flags && !set_kern_flags) 891 return -EINVAL; 892 893 /* how can we clone if the old one wasn't set up?? */ 894 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 895 896 /* if fs is reusing a sb, make sure that the contexts match */ 897 if (newsbsec->flags & SE_SBINITIALIZED) { 898 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 899 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 900 return selinux_cmp_sb_context(oldsb, newsb); 901 } 902 903 mutex_lock(&newsbsec->lock); 904 905 newsbsec->flags = oldsbsec->flags; 906 907 newsbsec->sid = oldsbsec->sid; 908 newsbsec->def_sid = oldsbsec->def_sid; 909 newsbsec->behavior = oldsbsec->behavior; 910 911 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 912 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 913 rc = security_fs_use(&selinux_state, newsb); 914 if (rc) 915 goto out; 916 } 917 918 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 919 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 920 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 921 } 922 923 if (set_context) { 924 u32 sid = oldsbsec->mntpoint_sid; 925 926 if (!set_fscontext) 927 newsbsec->sid = sid; 928 if (!set_rootcontext) { 929 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 930 newisec->sid = sid; 931 } 932 newsbsec->mntpoint_sid = sid; 933 } 934 if (set_rootcontext) { 935 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 936 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 937 938 newisec->sid = oldisec->sid; 939 } 940 941 sb_finish_set_opts(newsb); 942 out: 943 mutex_unlock(&newsbsec->lock); 944 return rc; 945 } 946 947 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 948 { 949 struct selinux_mnt_opts *opts = *mnt_opts; 950 951 if (token == Opt_seclabel) /* eaten and completely ignored */ 952 return 0; 953 954 if (!opts) { 955 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 956 if (!opts) 957 return -ENOMEM; 958 *mnt_opts = opts; 959 } 960 if (!s) 961 return -ENOMEM; 962 switch (token) { 963 case Opt_context: 964 if (opts->context || opts->defcontext) 965 goto Einval; 966 opts->context = s; 967 break; 968 case Opt_fscontext: 969 if (opts->fscontext) 970 goto Einval; 971 opts->fscontext = s; 972 break; 973 case Opt_rootcontext: 974 if (opts->rootcontext) 975 goto Einval; 976 opts->rootcontext = s; 977 break; 978 case Opt_defcontext: 979 if (opts->context || opts->defcontext) 980 goto Einval; 981 opts->defcontext = s; 982 break; 983 } 984 return 0; 985 Einval: 986 pr_warn(SEL_MOUNT_FAIL_MSG); 987 return -EINVAL; 988 } 989 990 static int selinux_add_mnt_opt(const char *option, const char *val, int len, 991 void **mnt_opts) 992 { 993 int token = Opt_error; 994 int rc, i; 995 996 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 997 if (strcmp(option, tokens[i].name) == 0) { 998 token = tokens[i].opt; 999 break; 1000 } 1001 } 1002 1003 if (token == Opt_error) 1004 return -EINVAL; 1005 1006 if (token != Opt_seclabel) { 1007 val = kmemdup_nul(val, len, GFP_KERNEL); 1008 if (!val) { 1009 rc = -ENOMEM; 1010 goto free_opt; 1011 } 1012 } 1013 rc = selinux_add_opt(token, val, mnt_opts); 1014 if (unlikely(rc)) { 1015 kfree(val); 1016 goto free_opt; 1017 } 1018 return rc; 1019 1020 free_opt: 1021 if (*mnt_opts) { 1022 selinux_free_mnt_opts(*mnt_opts); 1023 *mnt_opts = NULL; 1024 } 1025 return rc; 1026 } 1027 1028 static int show_sid(struct seq_file *m, u32 sid) 1029 { 1030 char *context = NULL; 1031 u32 len; 1032 int rc; 1033 1034 rc = security_sid_to_context(&selinux_state, sid, 1035 &context, &len); 1036 if (!rc) { 1037 bool has_comma = context && strchr(context, ','); 1038 1039 seq_putc(m, '='); 1040 if (has_comma) 1041 seq_putc(m, '\"'); 1042 seq_escape(m, context, "\"\n\\"); 1043 if (has_comma) 1044 seq_putc(m, '\"'); 1045 } 1046 kfree(context); 1047 return rc; 1048 } 1049 1050 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1051 { 1052 struct superblock_security_struct *sbsec = sb->s_security; 1053 int rc; 1054 1055 if (!(sbsec->flags & SE_SBINITIALIZED)) 1056 return 0; 1057 1058 if (!selinux_initialized(&selinux_state)) 1059 return 0; 1060 1061 if (sbsec->flags & FSCONTEXT_MNT) { 1062 seq_putc(m, ','); 1063 seq_puts(m, FSCONTEXT_STR); 1064 rc = show_sid(m, sbsec->sid); 1065 if (rc) 1066 return rc; 1067 } 1068 if (sbsec->flags & CONTEXT_MNT) { 1069 seq_putc(m, ','); 1070 seq_puts(m, CONTEXT_STR); 1071 rc = show_sid(m, sbsec->mntpoint_sid); 1072 if (rc) 1073 return rc; 1074 } 1075 if (sbsec->flags & DEFCONTEXT_MNT) { 1076 seq_putc(m, ','); 1077 seq_puts(m, DEFCONTEXT_STR); 1078 rc = show_sid(m, sbsec->def_sid); 1079 if (rc) 1080 return rc; 1081 } 1082 if (sbsec->flags & ROOTCONTEXT_MNT) { 1083 struct dentry *root = sb->s_root; 1084 struct inode_security_struct *isec = backing_inode_security(root); 1085 seq_putc(m, ','); 1086 seq_puts(m, ROOTCONTEXT_STR); 1087 rc = show_sid(m, isec->sid); 1088 if (rc) 1089 return rc; 1090 } 1091 if (sbsec->flags & SBLABEL_MNT) { 1092 seq_putc(m, ','); 1093 seq_puts(m, SECLABEL_STR); 1094 } 1095 return 0; 1096 } 1097 1098 static inline u16 inode_mode_to_security_class(umode_t mode) 1099 { 1100 switch (mode & S_IFMT) { 1101 case S_IFSOCK: 1102 return SECCLASS_SOCK_FILE; 1103 case S_IFLNK: 1104 return SECCLASS_LNK_FILE; 1105 case S_IFREG: 1106 return SECCLASS_FILE; 1107 case S_IFBLK: 1108 return SECCLASS_BLK_FILE; 1109 case S_IFDIR: 1110 return SECCLASS_DIR; 1111 case S_IFCHR: 1112 return SECCLASS_CHR_FILE; 1113 case S_IFIFO: 1114 return SECCLASS_FIFO_FILE; 1115 1116 } 1117 1118 return SECCLASS_FILE; 1119 } 1120 1121 static inline int default_protocol_stream(int protocol) 1122 { 1123 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1124 } 1125 1126 static inline int default_protocol_dgram(int protocol) 1127 { 1128 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1129 } 1130 1131 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1132 { 1133 int extsockclass = selinux_policycap_extsockclass(); 1134 1135 switch (family) { 1136 case PF_UNIX: 1137 switch (type) { 1138 case SOCK_STREAM: 1139 case SOCK_SEQPACKET: 1140 return SECCLASS_UNIX_STREAM_SOCKET; 1141 case SOCK_DGRAM: 1142 case SOCK_RAW: 1143 return SECCLASS_UNIX_DGRAM_SOCKET; 1144 } 1145 break; 1146 case PF_INET: 1147 case PF_INET6: 1148 switch (type) { 1149 case SOCK_STREAM: 1150 case SOCK_SEQPACKET: 1151 if (default_protocol_stream(protocol)) 1152 return SECCLASS_TCP_SOCKET; 1153 else if (extsockclass && protocol == IPPROTO_SCTP) 1154 return SECCLASS_SCTP_SOCKET; 1155 else 1156 return SECCLASS_RAWIP_SOCKET; 1157 case SOCK_DGRAM: 1158 if (default_protocol_dgram(protocol)) 1159 return SECCLASS_UDP_SOCKET; 1160 else if (extsockclass && (protocol == IPPROTO_ICMP || 1161 protocol == IPPROTO_ICMPV6)) 1162 return SECCLASS_ICMP_SOCKET; 1163 else 1164 return SECCLASS_RAWIP_SOCKET; 1165 case SOCK_DCCP: 1166 return SECCLASS_DCCP_SOCKET; 1167 default: 1168 return SECCLASS_RAWIP_SOCKET; 1169 } 1170 break; 1171 case PF_NETLINK: 1172 switch (protocol) { 1173 case NETLINK_ROUTE: 1174 return SECCLASS_NETLINK_ROUTE_SOCKET; 1175 case NETLINK_SOCK_DIAG: 1176 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1177 case NETLINK_NFLOG: 1178 return SECCLASS_NETLINK_NFLOG_SOCKET; 1179 case NETLINK_XFRM: 1180 return SECCLASS_NETLINK_XFRM_SOCKET; 1181 case NETLINK_SELINUX: 1182 return SECCLASS_NETLINK_SELINUX_SOCKET; 1183 case NETLINK_ISCSI: 1184 return SECCLASS_NETLINK_ISCSI_SOCKET; 1185 case NETLINK_AUDIT: 1186 return SECCLASS_NETLINK_AUDIT_SOCKET; 1187 case NETLINK_FIB_LOOKUP: 1188 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1189 case NETLINK_CONNECTOR: 1190 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1191 case NETLINK_NETFILTER: 1192 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1193 case NETLINK_DNRTMSG: 1194 return SECCLASS_NETLINK_DNRT_SOCKET; 1195 case NETLINK_KOBJECT_UEVENT: 1196 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1197 case NETLINK_GENERIC: 1198 return SECCLASS_NETLINK_GENERIC_SOCKET; 1199 case NETLINK_SCSITRANSPORT: 1200 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1201 case NETLINK_RDMA: 1202 return SECCLASS_NETLINK_RDMA_SOCKET; 1203 case NETLINK_CRYPTO: 1204 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1205 default: 1206 return SECCLASS_NETLINK_SOCKET; 1207 } 1208 case PF_PACKET: 1209 return SECCLASS_PACKET_SOCKET; 1210 case PF_KEY: 1211 return SECCLASS_KEY_SOCKET; 1212 case PF_APPLETALK: 1213 return SECCLASS_APPLETALK_SOCKET; 1214 } 1215 1216 if (extsockclass) { 1217 switch (family) { 1218 case PF_AX25: 1219 return SECCLASS_AX25_SOCKET; 1220 case PF_IPX: 1221 return SECCLASS_IPX_SOCKET; 1222 case PF_NETROM: 1223 return SECCLASS_NETROM_SOCKET; 1224 case PF_ATMPVC: 1225 return SECCLASS_ATMPVC_SOCKET; 1226 case PF_X25: 1227 return SECCLASS_X25_SOCKET; 1228 case PF_ROSE: 1229 return SECCLASS_ROSE_SOCKET; 1230 case PF_DECnet: 1231 return SECCLASS_DECNET_SOCKET; 1232 case PF_ATMSVC: 1233 return SECCLASS_ATMSVC_SOCKET; 1234 case PF_RDS: 1235 return SECCLASS_RDS_SOCKET; 1236 case PF_IRDA: 1237 return SECCLASS_IRDA_SOCKET; 1238 case PF_PPPOX: 1239 return SECCLASS_PPPOX_SOCKET; 1240 case PF_LLC: 1241 return SECCLASS_LLC_SOCKET; 1242 case PF_CAN: 1243 return SECCLASS_CAN_SOCKET; 1244 case PF_TIPC: 1245 return SECCLASS_TIPC_SOCKET; 1246 case PF_BLUETOOTH: 1247 return SECCLASS_BLUETOOTH_SOCKET; 1248 case PF_IUCV: 1249 return SECCLASS_IUCV_SOCKET; 1250 case PF_RXRPC: 1251 return SECCLASS_RXRPC_SOCKET; 1252 case PF_ISDN: 1253 return SECCLASS_ISDN_SOCKET; 1254 case PF_PHONET: 1255 return SECCLASS_PHONET_SOCKET; 1256 case PF_IEEE802154: 1257 return SECCLASS_IEEE802154_SOCKET; 1258 case PF_CAIF: 1259 return SECCLASS_CAIF_SOCKET; 1260 case PF_ALG: 1261 return SECCLASS_ALG_SOCKET; 1262 case PF_NFC: 1263 return SECCLASS_NFC_SOCKET; 1264 case PF_VSOCK: 1265 return SECCLASS_VSOCK_SOCKET; 1266 case PF_KCM: 1267 return SECCLASS_KCM_SOCKET; 1268 case PF_QIPCRTR: 1269 return SECCLASS_QIPCRTR_SOCKET; 1270 case PF_SMC: 1271 return SECCLASS_SMC_SOCKET; 1272 case PF_XDP: 1273 return SECCLASS_XDP_SOCKET; 1274 #if PF_MAX > 45 1275 #error New address family defined, please update this function. 1276 #endif 1277 } 1278 } 1279 1280 return SECCLASS_SOCKET; 1281 } 1282 1283 static int selinux_genfs_get_sid(struct dentry *dentry, 1284 u16 tclass, 1285 u16 flags, 1286 u32 *sid) 1287 { 1288 int rc; 1289 struct super_block *sb = dentry->d_sb; 1290 char *buffer, *path; 1291 1292 buffer = (char *)__get_free_page(GFP_KERNEL); 1293 if (!buffer) 1294 return -ENOMEM; 1295 1296 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1297 if (IS_ERR(path)) 1298 rc = PTR_ERR(path); 1299 else { 1300 if (flags & SE_SBPROC) { 1301 /* each process gets a /proc/PID/ entry. Strip off the 1302 * PID part to get a valid selinux labeling. 1303 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1304 while (path[1] >= '0' && path[1] <= '9') { 1305 path[1] = '/'; 1306 path++; 1307 } 1308 } 1309 rc = security_genfs_sid(&selinux_state, sb->s_type->name, 1310 path, tclass, sid); 1311 if (rc == -ENOENT) { 1312 /* No match in policy, mark as unlabeled. */ 1313 *sid = SECINITSID_UNLABELED; 1314 rc = 0; 1315 } 1316 } 1317 free_page((unsigned long)buffer); 1318 return rc; 1319 } 1320 1321 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1322 u32 def_sid, u32 *sid) 1323 { 1324 #define INITCONTEXTLEN 255 1325 char *context; 1326 unsigned int len; 1327 int rc; 1328 1329 len = INITCONTEXTLEN; 1330 context = kmalloc(len + 1, GFP_NOFS); 1331 if (!context) 1332 return -ENOMEM; 1333 1334 context[len] = '\0'; 1335 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1336 if (rc == -ERANGE) { 1337 kfree(context); 1338 1339 /* Need a larger buffer. Query for the right size. */ 1340 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1341 if (rc < 0) 1342 return rc; 1343 1344 len = rc; 1345 context = kmalloc(len + 1, GFP_NOFS); 1346 if (!context) 1347 return -ENOMEM; 1348 1349 context[len] = '\0'; 1350 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1351 context, len); 1352 } 1353 if (rc < 0) { 1354 kfree(context); 1355 if (rc != -ENODATA) { 1356 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1357 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1358 return rc; 1359 } 1360 *sid = def_sid; 1361 return 0; 1362 } 1363 1364 rc = security_context_to_sid_default(&selinux_state, context, rc, sid, 1365 def_sid, GFP_NOFS); 1366 if (rc) { 1367 char *dev = inode->i_sb->s_id; 1368 unsigned long ino = inode->i_ino; 1369 1370 if (rc == -EINVAL) { 1371 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", 1372 ino, dev, context); 1373 } else { 1374 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1375 __func__, context, -rc, dev, ino); 1376 } 1377 } 1378 kfree(context); 1379 return 0; 1380 } 1381 1382 /* The inode's security attributes must be initialized before first use. */ 1383 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1384 { 1385 struct superblock_security_struct *sbsec = NULL; 1386 struct inode_security_struct *isec = selinux_inode(inode); 1387 u32 task_sid, sid = 0; 1388 u16 sclass; 1389 struct dentry *dentry; 1390 int rc = 0; 1391 1392 if (isec->initialized == LABEL_INITIALIZED) 1393 return 0; 1394 1395 spin_lock(&isec->lock); 1396 if (isec->initialized == LABEL_INITIALIZED) 1397 goto out_unlock; 1398 1399 if (isec->sclass == SECCLASS_FILE) 1400 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1401 1402 sbsec = inode->i_sb->s_security; 1403 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1404 /* Defer initialization until selinux_complete_init, 1405 after the initial policy is loaded and the security 1406 server is ready to handle calls. */ 1407 spin_lock(&sbsec->isec_lock); 1408 if (list_empty(&isec->list)) 1409 list_add(&isec->list, &sbsec->isec_head); 1410 spin_unlock(&sbsec->isec_lock); 1411 goto out_unlock; 1412 } 1413 1414 sclass = isec->sclass; 1415 task_sid = isec->task_sid; 1416 sid = isec->sid; 1417 isec->initialized = LABEL_PENDING; 1418 spin_unlock(&isec->lock); 1419 1420 switch (sbsec->behavior) { 1421 case SECURITY_FS_USE_NATIVE: 1422 break; 1423 case SECURITY_FS_USE_XATTR: 1424 if (!(inode->i_opflags & IOP_XATTR)) { 1425 sid = sbsec->def_sid; 1426 break; 1427 } 1428 /* Need a dentry, since the xattr API requires one. 1429 Life would be simpler if we could just pass the inode. */ 1430 if (opt_dentry) { 1431 /* Called from d_instantiate or d_splice_alias. */ 1432 dentry = dget(opt_dentry); 1433 } else { 1434 /* 1435 * Called from selinux_complete_init, try to find a dentry. 1436 * Some filesystems really want a connected one, so try 1437 * that first. We could split SECURITY_FS_USE_XATTR in 1438 * two, depending upon that... 1439 */ 1440 dentry = d_find_alias(inode); 1441 if (!dentry) 1442 dentry = d_find_any_alias(inode); 1443 } 1444 if (!dentry) { 1445 /* 1446 * this is can be hit on boot when a file is accessed 1447 * before the policy is loaded. When we load policy we 1448 * may find inodes that have no dentry on the 1449 * sbsec->isec_head list. No reason to complain as these 1450 * will get fixed up the next time we go through 1451 * inode_doinit with a dentry, before these inodes could 1452 * be used again by userspace. 1453 */ 1454 goto out_invalid; 1455 } 1456 1457 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1458 &sid); 1459 dput(dentry); 1460 if (rc) 1461 goto out; 1462 break; 1463 case SECURITY_FS_USE_TASK: 1464 sid = task_sid; 1465 break; 1466 case SECURITY_FS_USE_TRANS: 1467 /* Default to the fs SID. */ 1468 sid = sbsec->sid; 1469 1470 /* Try to obtain a transition SID. */ 1471 rc = security_transition_sid(&selinux_state, task_sid, sid, 1472 sclass, NULL, &sid); 1473 if (rc) 1474 goto out; 1475 break; 1476 case SECURITY_FS_USE_MNTPOINT: 1477 sid = sbsec->mntpoint_sid; 1478 break; 1479 default: 1480 /* Default to the fs superblock SID. */ 1481 sid = sbsec->sid; 1482 1483 if ((sbsec->flags & SE_SBGENFS) && 1484 (!S_ISLNK(inode->i_mode) || 1485 selinux_policycap_genfs_seclabel_symlinks())) { 1486 /* We must have a dentry to determine the label on 1487 * procfs inodes */ 1488 if (opt_dentry) { 1489 /* Called from d_instantiate or 1490 * d_splice_alias. */ 1491 dentry = dget(opt_dentry); 1492 } else { 1493 /* Called from selinux_complete_init, try to 1494 * find a dentry. Some filesystems really want 1495 * a connected one, so try that first. 1496 */ 1497 dentry = d_find_alias(inode); 1498 if (!dentry) 1499 dentry = d_find_any_alias(inode); 1500 } 1501 /* 1502 * This can be hit on boot when a file is accessed 1503 * before the policy is loaded. When we load policy we 1504 * may find inodes that have no dentry on the 1505 * sbsec->isec_head list. No reason to complain as 1506 * these will get fixed up the next time we go through 1507 * inode_doinit() with a dentry, before these inodes 1508 * could be used again by userspace. 1509 */ 1510 if (!dentry) 1511 goto out_invalid; 1512 rc = selinux_genfs_get_sid(dentry, sclass, 1513 sbsec->flags, &sid); 1514 if (rc) { 1515 dput(dentry); 1516 goto out; 1517 } 1518 1519 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1520 (inode->i_opflags & IOP_XATTR)) { 1521 rc = inode_doinit_use_xattr(inode, dentry, 1522 sid, &sid); 1523 if (rc) { 1524 dput(dentry); 1525 goto out; 1526 } 1527 } 1528 dput(dentry); 1529 } 1530 break; 1531 } 1532 1533 out: 1534 spin_lock(&isec->lock); 1535 if (isec->initialized == LABEL_PENDING) { 1536 if (rc) { 1537 isec->initialized = LABEL_INVALID; 1538 goto out_unlock; 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 out_invalid: 1549 spin_lock(&isec->lock); 1550 if (isec->initialized == LABEL_PENDING) { 1551 isec->initialized = LABEL_INVALID; 1552 isec->sid = sid; 1553 } 1554 spin_unlock(&isec->lock); 1555 return 0; 1556 } 1557 1558 /* Convert a Linux signal to an access vector. */ 1559 static inline u32 signal_to_av(int sig) 1560 { 1561 u32 perm = 0; 1562 1563 switch (sig) { 1564 case SIGCHLD: 1565 /* Commonly granted from child to parent. */ 1566 perm = PROCESS__SIGCHLD; 1567 break; 1568 case SIGKILL: 1569 /* Cannot be caught or ignored */ 1570 perm = PROCESS__SIGKILL; 1571 break; 1572 case SIGSTOP: 1573 /* Cannot be caught or ignored */ 1574 perm = PROCESS__SIGSTOP; 1575 break; 1576 default: 1577 /* All other signals. */ 1578 perm = PROCESS__SIGNAL; 1579 break; 1580 } 1581 1582 return perm; 1583 } 1584 1585 #if CAP_LAST_CAP > 63 1586 #error Fix SELinux to handle capabilities > 63. 1587 #endif 1588 1589 /* Check whether a task is allowed to use a capability. */ 1590 static int cred_has_capability(const struct cred *cred, 1591 int cap, unsigned int opts, bool initns) 1592 { 1593 struct common_audit_data ad; 1594 struct av_decision avd; 1595 u16 sclass; 1596 u32 sid = cred_sid(cred); 1597 u32 av = CAP_TO_MASK(cap); 1598 int rc; 1599 1600 ad.type = LSM_AUDIT_DATA_CAP; 1601 ad.u.cap = cap; 1602 1603 switch (CAP_TO_INDEX(cap)) { 1604 case 0: 1605 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1606 break; 1607 case 1: 1608 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1609 break; 1610 default: 1611 pr_err("SELinux: out of range capability %d\n", cap); 1612 BUG(); 1613 return -EINVAL; 1614 } 1615 1616 rc = avc_has_perm_noaudit(&selinux_state, 1617 sid, sid, sclass, av, 0, &avd); 1618 if (!(opts & CAP_OPT_NOAUDIT)) { 1619 int rc2 = avc_audit(&selinux_state, 1620 sid, sid, sclass, av, &avd, rc, &ad, 0); 1621 if (rc2) 1622 return rc2; 1623 } 1624 return rc; 1625 } 1626 1627 /* Check whether a task has a particular permission to an inode. 1628 The 'adp' parameter is optional and allows other audit 1629 data to be passed (e.g. the dentry). */ 1630 static int inode_has_perm(const struct cred *cred, 1631 struct inode *inode, 1632 u32 perms, 1633 struct common_audit_data *adp) 1634 { 1635 struct inode_security_struct *isec; 1636 u32 sid; 1637 1638 validate_creds(cred); 1639 1640 if (unlikely(IS_PRIVATE(inode))) 1641 return 0; 1642 1643 sid = cred_sid(cred); 1644 isec = selinux_inode(inode); 1645 1646 return avc_has_perm(&selinux_state, 1647 sid, isec->sid, isec->sclass, perms, adp); 1648 } 1649 1650 /* Same as inode_has_perm, but pass explicit audit data containing 1651 the dentry to help the auditing code to more easily generate the 1652 pathname if needed. */ 1653 static inline int dentry_has_perm(const struct cred *cred, 1654 struct dentry *dentry, 1655 u32 av) 1656 { 1657 struct inode *inode = d_backing_inode(dentry); 1658 struct common_audit_data ad; 1659 1660 ad.type = LSM_AUDIT_DATA_DENTRY; 1661 ad.u.dentry = dentry; 1662 __inode_security_revalidate(inode, dentry, true); 1663 return inode_has_perm(cred, inode, av, &ad); 1664 } 1665 1666 /* Same as inode_has_perm, but pass explicit audit data containing 1667 the path to help the auditing code to more easily generate the 1668 pathname if needed. */ 1669 static inline int path_has_perm(const struct cred *cred, 1670 const struct path *path, 1671 u32 av) 1672 { 1673 struct inode *inode = d_backing_inode(path->dentry); 1674 struct common_audit_data ad; 1675 1676 ad.type = LSM_AUDIT_DATA_PATH; 1677 ad.u.path = *path; 1678 __inode_security_revalidate(inode, path->dentry, true); 1679 return inode_has_perm(cred, inode, av, &ad); 1680 } 1681 1682 /* Same as path_has_perm, but uses the inode from the file struct. */ 1683 static inline int file_path_has_perm(const struct cred *cred, 1684 struct file *file, 1685 u32 av) 1686 { 1687 struct common_audit_data ad; 1688 1689 ad.type = LSM_AUDIT_DATA_FILE; 1690 ad.u.file = file; 1691 return inode_has_perm(cred, file_inode(file), av, &ad); 1692 } 1693 1694 #ifdef CONFIG_BPF_SYSCALL 1695 static int bpf_fd_pass(struct file *file, u32 sid); 1696 #endif 1697 1698 /* Check whether a task can use an open file descriptor to 1699 access an inode in a given way. Check access to the 1700 descriptor itself, and then use dentry_has_perm to 1701 check a particular permission to the file. 1702 Access to the descriptor is implicitly granted if it 1703 has the same SID as the process. If av is zero, then 1704 access to the file is not checked, e.g. for cases 1705 where only the descriptor is affected like seek. */ 1706 static int file_has_perm(const struct cred *cred, 1707 struct file *file, 1708 u32 av) 1709 { 1710 struct file_security_struct *fsec = selinux_file(file); 1711 struct inode *inode = file_inode(file); 1712 struct common_audit_data ad; 1713 u32 sid = cred_sid(cred); 1714 int rc; 1715 1716 ad.type = LSM_AUDIT_DATA_FILE; 1717 ad.u.file = file; 1718 1719 if (sid != fsec->sid) { 1720 rc = avc_has_perm(&selinux_state, 1721 sid, fsec->sid, 1722 SECCLASS_FD, 1723 FD__USE, 1724 &ad); 1725 if (rc) 1726 goto out; 1727 } 1728 1729 #ifdef CONFIG_BPF_SYSCALL 1730 rc = bpf_fd_pass(file, cred_sid(cred)); 1731 if (rc) 1732 return rc; 1733 #endif 1734 1735 /* av is zero if only checking access to the descriptor. */ 1736 rc = 0; 1737 if (av) 1738 rc = inode_has_perm(cred, inode, av, &ad); 1739 1740 out: 1741 return rc; 1742 } 1743 1744 /* 1745 * Determine the label for an inode that might be unioned. 1746 */ 1747 static int 1748 selinux_determine_inode_label(const struct task_security_struct *tsec, 1749 struct inode *dir, 1750 const struct qstr *name, u16 tclass, 1751 u32 *_new_isid) 1752 { 1753 const struct superblock_security_struct *sbsec = dir->i_sb->s_security; 1754 1755 if ((sbsec->flags & SE_SBINITIALIZED) && 1756 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1757 *_new_isid = sbsec->mntpoint_sid; 1758 } else if ((sbsec->flags & SBLABEL_MNT) && 1759 tsec->create_sid) { 1760 *_new_isid = tsec->create_sid; 1761 } else { 1762 const struct inode_security_struct *dsec = inode_security(dir); 1763 return security_transition_sid(&selinux_state, tsec->sid, 1764 dsec->sid, tclass, 1765 name, _new_isid); 1766 } 1767 1768 return 0; 1769 } 1770 1771 /* Check whether a task can create a file. */ 1772 static int may_create(struct inode *dir, 1773 struct dentry *dentry, 1774 u16 tclass) 1775 { 1776 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1777 struct inode_security_struct *dsec; 1778 struct superblock_security_struct *sbsec; 1779 u32 sid, newsid; 1780 struct common_audit_data ad; 1781 int rc; 1782 1783 dsec = inode_security(dir); 1784 sbsec = dir->i_sb->s_security; 1785 1786 sid = tsec->sid; 1787 1788 ad.type = LSM_AUDIT_DATA_DENTRY; 1789 ad.u.dentry = dentry; 1790 1791 rc = avc_has_perm(&selinux_state, 1792 sid, dsec->sid, SECCLASS_DIR, 1793 DIR__ADD_NAME | DIR__SEARCH, 1794 &ad); 1795 if (rc) 1796 return rc; 1797 1798 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1799 &newsid); 1800 if (rc) 1801 return rc; 1802 1803 rc = avc_has_perm(&selinux_state, 1804 sid, newsid, tclass, FILE__CREATE, &ad); 1805 if (rc) 1806 return rc; 1807 1808 return avc_has_perm(&selinux_state, 1809 newsid, sbsec->sid, 1810 SECCLASS_FILESYSTEM, 1811 FILESYSTEM__ASSOCIATE, &ad); 1812 } 1813 1814 #define MAY_LINK 0 1815 #define MAY_UNLINK 1 1816 #define MAY_RMDIR 2 1817 1818 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1819 static int may_link(struct inode *dir, 1820 struct dentry *dentry, 1821 int kind) 1822 1823 { 1824 struct inode_security_struct *dsec, *isec; 1825 struct common_audit_data ad; 1826 u32 sid = current_sid(); 1827 u32 av; 1828 int rc; 1829 1830 dsec = inode_security(dir); 1831 isec = backing_inode_security(dentry); 1832 1833 ad.type = LSM_AUDIT_DATA_DENTRY; 1834 ad.u.dentry = dentry; 1835 1836 av = DIR__SEARCH; 1837 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1838 rc = avc_has_perm(&selinux_state, 1839 sid, dsec->sid, SECCLASS_DIR, av, &ad); 1840 if (rc) 1841 return rc; 1842 1843 switch (kind) { 1844 case MAY_LINK: 1845 av = FILE__LINK; 1846 break; 1847 case MAY_UNLINK: 1848 av = FILE__UNLINK; 1849 break; 1850 case MAY_RMDIR: 1851 av = DIR__RMDIR; 1852 break; 1853 default: 1854 pr_warn("SELinux: %s: unrecognized kind %d\n", 1855 __func__, kind); 1856 return 0; 1857 } 1858 1859 rc = avc_has_perm(&selinux_state, 1860 sid, isec->sid, isec->sclass, av, &ad); 1861 return rc; 1862 } 1863 1864 static inline int may_rename(struct inode *old_dir, 1865 struct dentry *old_dentry, 1866 struct inode *new_dir, 1867 struct dentry *new_dentry) 1868 { 1869 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1870 struct common_audit_data ad; 1871 u32 sid = current_sid(); 1872 u32 av; 1873 int old_is_dir, new_is_dir; 1874 int rc; 1875 1876 old_dsec = inode_security(old_dir); 1877 old_isec = backing_inode_security(old_dentry); 1878 old_is_dir = d_is_dir(old_dentry); 1879 new_dsec = inode_security(new_dir); 1880 1881 ad.type = LSM_AUDIT_DATA_DENTRY; 1882 1883 ad.u.dentry = old_dentry; 1884 rc = avc_has_perm(&selinux_state, 1885 sid, old_dsec->sid, SECCLASS_DIR, 1886 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1887 if (rc) 1888 return rc; 1889 rc = avc_has_perm(&selinux_state, 1890 sid, old_isec->sid, 1891 old_isec->sclass, FILE__RENAME, &ad); 1892 if (rc) 1893 return rc; 1894 if (old_is_dir && new_dir != old_dir) { 1895 rc = avc_has_perm(&selinux_state, 1896 sid, old_isec->sid, 1897 old_isec->sclass, DIR__REPARENT, &ad); 1898 if (rc) 1899 return rc; 1900 } 1901 1902 ad.u.dentry = new_dentry; 1903 av = DIR__ADD_NAME | DIR__SEARCH; 1904 if (d_is_positive(new_dentry)) 1905 av |= DIR__REMOVE_NAME; 1906 rc = avc_has_perm(&selinux_state, 1907 sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1908 if (rc) 1909 return rc; 1910 if (d_is_positive(new_dentry)) { 1911 new_isec = backing_inode_security(new_dentry); 1912 new_is_dir = d_is_dir(new_dentry); 1913 rc = avc_has_perm(&selinux_state, 1914 sid, new_isec->sid, 1915 new_isec->sclass, 1916 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1917 if (rc) 1918 return rc; 1919 } 1920 1921 return 0; 1922 } 1923 1924 /* Check whether a task can perform a filesystem operation. */ 1925 static int superblock_has_perm(const struct cred *cred, 1926 struct super_block *sb, 1927 u32 perms, 1928 struct common_audit_data *ad) 1929 { 1930 struct superblock_security_struct *sbsec; 1931 u32 sid = cred_sid(cred); 1932 1933 sbsec = sb->s_security; 1934 return avc_has_perm(&selinux_state, 1935 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1936 } 1937 1938 /* Convert a Linux mode and permission mask to an access vector. */ 1939 static inline u32 file_mask_to_av(int mode, int mask) 1940 { 1941 u32 av = 0; 1942 1943 if (!S_ISDIR(mode)) { 1944 if (mask & MAY_EXEC) 1945 av |= FILE__EXECUTE; 1946 if (mask & MAY_READ) 1947 av |= FILE__READ; 1948 1949 if (mask & MAY_APPEND) 1950 av |= FILE__APPEND; 1951 else if (mask & MAY_WRITE) 1952 av |= FILE__WRITE; 1953 1954 } else { 1955 if (mask & MAY_EXEC) 1956 av |= DIR__SEARCH; 1957 if (mask & MAY_WRITE) 1958 av |= DIR__WRITE; 1959 if (mask & MAY_READ) 1960 av |= DIR__READ; 1961 } 1962 1963 return av; 1964 } 1965 1966 /* Convert a Linux file to an access vector. */ 1967 static inline u32 file_to_av(struct file *file) 1968 { 1969 u32 av = 0; 1970 1971 if (file->f_mode & FMODE_READ) 1972 av |= FILE__READ; 1973 if (file->f_mode & FMODE_WRITE) { 1974 if (file->f_flags & O_APPEND) 1975 av |= FILE__APPEND; 1976 else 1977 av |= FILE__WRITE; 1978 } 1979 if (!av) { 1980 /* 1981 * Special file opened with flags 3 for ioctl-only use. 1982 */ 1983 av = FILE__IOCTL; 1984 } 1985 1986 return av; 1987 } 1988 1989 /* 1990 * Convert a file to an access vector and include the correct 1991 * open permission. 1992 */ 1993 static inline u32 open_file_to_av(struct file *file) 1994 { 1995 u32 av = file_to_av(file); 1996 struct inode *inode = file_inode(file); 1997 1998 if (selinux_policycap_openperm() && 1999 inode->i_sb->s_magic != SOCKFS_MAGIC) 2000 av |= FILE__OPEN; 2001 2002 return av; 2003 } 2004 2005 /* Hook functions begin here. */ 2006 2007 static int selinux_binder_set_context_mgr(struct task_struct *mgr) 2008 { 2009 u32 mysid = current_sid(); 2010 u32 mgrsid = task_sid(mgr); 2011 2012 return avc_has_perm(&selinux_state, 2013 mysid, mgrsid, SECCLASS_BINDER, 2014 BINDER__SET_CONTEXT_MGR, NULL); 2015 } 2016 2017 static int selinux_binder_transaction(struct task_struct *from, 2018 struct task_struct *to) 2019 { 2020 u32 mysid = current_sid(); 2021 u32 fromsid = task_sid(from); 2022 u32 tosid = task_sid(to); 2023 int rc; 2024 2025 if (mysid != fromsid) { 2026 rc = avc_has_perm(&selinux_state, 2027 mysid, fromsid, SECCLASS_BINDER, 2028 BINDER__IMPERSONATE, NULL); 2029 if (rc) 2030 return rc; 2031 } 2032 2033 return avc_has_perm(&selinux_state, 2034 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, 2035 NULL); 2036 } 2037 2038 static int selinux_binder_transfer_binder(struct task_struct *from, 2039 struct task_struct *to) 2040 { 2041 u32 fromsid = task_sid(from); 2042 u32 tosid = task_sid(to); 2043 2044 return avc_has_perm(&selinux_state, 2045 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, 2046 NULL); 2047 } 2048 2049 static int selinux_binder_transfer_file(struct task_struct *from, 2050 struct task_struct *to, 2051 struct file *file) 2052 { 2053 u32 sid = task_sid(to); 2054 struct file_security_struct *fsec = selinux_file(file); 2055 struct dentry *dentry = file->f_path.dentry; 2056 struct inode_security_struct *isec; 2057 struct common_audit_data ad; 2058 int rc; 2059 2060 ad.type = LSM_AUDIT_DATA_PATH; 2061 ad.u.path = file->f_path; 2062 2063 if (sid != fsec->sid) { 2064 rc = avc_has_perm(&selinux_state, 2065 sid, fsec->sid, 2066 SECCLASS_FD, 2067 FD__USE, 2068 &ad); 2069 if (rc) 2070 return rc; 2071 } 2072 2073 #ifdef CONFIG_BPF_SYSCALL 2074 rc = bpf_fd_pass(file, sid); 2075 if (rc) 2076 return rc; 2077 #endif 2078 2079 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2080 return 0; 2081 2082 isec = backing_inode_security(dentry); 2083 return avc_has_perm(&selinux_state, 2084 sid, isec->sid, isec->sclass, file_to_av(file), 2085 &ad); 2086 } 2087 2088 static int selinux_ptrace_access_check(struct task_struct *child, 2089 unsigned int mode) 2090 { 2091 u32 sid = current_sid(); 2092 u32 csid = task_sid(child); 2093 2094 if (mode & PTRACE_MODE_READ) 2095 return avc_has_perm(&selinux_state, 2096 sid, csid, SECCLASS_FILE, FILE__READ, NULL); 2097 2098 return avc_has_perm(&selinux_state, 2099 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2100 } 2101 2102 static int selinux_ptrace_traceme(struct task_struct *parent) 2103 { 2104 return avc_has_perm(&selinux_state, 2105 task_sid(parent), current_sid(), SECCLASS_PROCESS, 2106 PROCESS__PTRACE, NULL); 2107 } 2108 2109 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 2110 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2111 { 2112 return avc_has_perm(&selinux_state, 2113 current_sid(), task_sid(target), SECCLASS_PROCESS, 2114 PROCESS__GETCAP, NULL); 2115 } 2116 2117 static int selinux_capset(struct cred *new, const struct cred *old, 2118 const kernel_cap_t *effective, 2119 const kernel_cap_t *inheritable, 2120 const kernel_cap_t *permitted) 2121 { 2122 return avc_has_perm(&selinux_state, 2123 cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2124 PROCESS__SETCAP, NULL); 2125 } 2126 2127 /* 2128 * (This comment used to live with the selinux_task_setuid hook, 2129 * which was removed). 2130 * 2131 * Since setuid only affects the current process, and since the SELinux 2132 * controls are not based on the Linux identity attributes, SELinux does not 2133 * need to control this operation. However, SELinux does control the use of 2134 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2135 */ 2136 2137 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2138 int cap, unsigned int opts) 2139 { 2140 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2141 } 2142 2143 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2144 { 2145 const struct cred *cred = current_cred(); 2146 int rc = 0; 2147 2148 if (!sb) 2149 return 0; 2150 2151 switch (cmds) { 2152 case Q_SYNC: 2153 case Q_QUOTAON: 2154 case Q_QUOTAOFF: 2155 case Q_SETINFO: 2156 case Q_SETQUOTA: 2157 case Q_XQUOTAOFF: 2158 case Q_XQUOTAON: 2159 case Q_XSETQLIM: 2160 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2161 break; 2162 case Q_GETFMT: 2163 case Q_GETINFO: 2164 case Q_GETQUOTA: 2165 case Q_XGETQUOTA: 2166 case Q_XGETQSTAT: 2167 case Q_XGETQSTATV: 2168 case Q_XGETNEXTQUOTA: 2169 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2170 break; 2171 default: 2172 rc = 0; /* let the kernel handle invalid cmds */ 2173 break; 2174 } 2175 return rc; 2176 } 2177 2178 static int selinux_quota_on(struct dentry *dentry) 2179 { 2180 const struct cred *cred = current_cred(); 2181 2182 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2183 } 2184 2185 static int selinux_syslog(int type) 2186 { 2187 switch (type) { 2188 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2189 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2190 return avc_has_perm(&selinux_state, 2191 current_sid(), SECINITSID_KERNEL, 2192 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2193 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2194 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2195 /* Set level of messages printed to console */ 2196 case SYSLOG_ACTION_CONSOLE_LEVEL: 2197 return avc_has_perm(&selinux_state, 2198 current_sid(), SECINITSID_KERNEL, 2199 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2200 NULL); 2201 } 2202 /* All other syslog types */ 2203 return avc_has_perm(&selinux_state, 2204 current_sid(), SECINITSID_KERNEL, 2205 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2206 } 2207 2208 /* 2209 * Check that a process has enough memory to allocate a new virtual 2210 * mapping. 0 means there is enough memory for the allocation to 2211 * succeed and -ENOMEM implies there is not. 2212 * 2213 * Do not audit the selinux permission check, as this is applied to all 2214 * processes that allocate mappings. 2215 */ 2216 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2217 { 2218 int rc, cap_sys_admin = 0; 2219 2220 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2221 CAP_OPT_NOAUDIT, true); 2222 if (rc == 0) 2223 cap_sys_admin = 1; 2224 2225 return cap_sys_admin; 2226 } 2227 2228 /* binprm security operations */ 2229 2230 static u32 ptrace_parent_sid(void) 2231 { 2232 u32 sid = 0; 2233 struct task_struct *tracer; 2234 2235 rcu_read_lock(); 2236 tracer = ptrace_parent(current); 2237 if (tracer) 2238 sid = task_sid(tracer); 2239 rcu_read_unlock(); 2240 2241 return sid; 2242 } 2243 2244 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2245 const struct task_security_struct *old_tsec, 2246 const struct task_security_struct *new_tsec) 2247 { 2248 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2249 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2250 int rc; 2251 u32 av; 2252 2253 if (!nnp && !nosuid) 2254 return 0; /* neither NNP nor nosuid */ 2255 2256 if (new_tsec->sid == old_tsec->sid) 2257 return 0; /* No change in credentials */ 2258 2259 /* 2260 * If the policy enables the nnp_nosuid_transition policy capability, 2261 * then we permit transitions under NNP or nosuid if the 2262 * policy allows the corresponding permission between 2263 * the old and new contexts. 2264 */ 2265 if (selinux_policycap_nnp_nosuid_transition()) { 2266 av = 0; 2267 if (nnp) 2268 av |= PROCESS2__NNP_TRANSITION; 2269 if (nosuid) 2270 av |= PROCESS2__NOSUID_TRANSITION; 2271 rc = avc_has_perm(&selinux_state, 2272 old_tsec->sid, new_tsec->sid, 2273 SECCLASS_PROCESS2, av, NULL); 2274 if (!rc) 2275 return 0; 2276 } 2277 2278 /* 2279 * We also permit NNP or nosuid transitions to bounded SIDs, 2280 * i.e. SIDs that are guaranteed to only be allowed a subset 2281 * of the permissions of the current SID. 2282 */ 2283 rc = security_bounded_transition(&selinux_state, old_tsec->sid, 2284 new_tsec->sid); 2285 if (!rc) 2286 return 0; 2287 2288 /* 2289 * On failure, preserve the errno values for NNP vs nosuid. 2290 * NNP: Operation not permitted for caller. 2291 * nosuid: Permission denied to file. 2292 */ 2293 if (nnp) 2294 return -EPERM; 2295 return -EACCES; 2296 } 2297 2298 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2299 { 2300 const struct task_security_struct *old_tsec; 2301 struct task_security_struct *new_tsec; 2302 struct inode_security_struct *isec; 2303 struct common_audit_data ad; 2304 struct inode *inode = file_inode(bprm->file); 2305 int rc; 2306 2307 /* SELinux context only depends on initial program or script and not 2308 * the script interpreter */ 2309 2310 old_tsec = selinux_cred(current_cred()); 2311 new_tsec = selinux_cred(bprm->cred); 2312 isec = inode_security(inode); 2313 2314 /* Default to the current task SID. */ 2315 new_tsec->sid = old_tsec->sid; 2316 new_tsec->osid = old_tsec->sid; 2317 2318 /* Reset fs, key, and sock SIDs on execve. */ 2319 new_tsec->create_sid = 0; 2320 new_tsec->keycreate_sid = 0; 2321 new_tsec->sockcreate_sid = 0; 2322 2323 if (old_tsec->exec_sid) { 2324 new_tsec->sid = old_tsec->exec_sid; 2325 /* Reset exec SID on execve. */ 2326 new_tsec->exec_sid = 0; 2327 2328 /* Fail on NNP or nosuid if not an allowed transition. */ 2329 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2330 if (rc) 2331 return rc; 2332 } else { 2333 /* Check for a default transition on this program. */ 2334 rc = security_transition_sid(&selinux_state, old_tsec->sid, 2335 isec->sid, SECCLASS_PROCESS, NULL, 2336 &new_tsec->sid); 2337 if (rc) 2338 return rc; 2339 2340 /* 2341 * Fallback to old SID on NNP or nosuid if not an allowed 2342 * transition. 2343 */ 2344 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2345 if (rc) 2346 new_tsec->sid = old_tsec->sid; 2347 } 2348 2349 ad.type = LSM_AUDIT_DATA_FILE; 2350 ad.u.file = bprm->file; 2351 2352 if (new_tsec->sid == old_tsec->sid) { 2353 rc = avc_has_perm(&selinux_state, 2354 old_tsec->sid, isec->sid, 2355 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2356 if (rc) 2357 return rc; 2358 } else { 2359 /* Check permissions for the transition. */ 2360 rc = avc_has_perm(&selinux_state, 2361 old_tsec->sid, new_tsec->sid, 2362 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2363 if (rc) 2364 return rc; 2365 2366 rc = avc_has_perm(&selinux_state, 2367 new_tsec->sid, isec->sid, 2368 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2369 if (rc) 2370 return rc; 2371 2372 /* Check for shared state */ 2373 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2374 rc = avc_has_perm(&selinux_state, 2375 old_tsec->sid, new_tsec->sid, 2376 SECCLASS_PROCESS, PROCESS__SHARE, 2377 NULL); 2378 if (rc) 2379 return -EPERM; 2380 } 2381 2382 /* Make sure that anyone attempting to ptrace over a task that 2383 * changes its SID has the appropriate permit */ 2384 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2385 u32 ptsid = ptrace_parent_sid(); 2386 if (ptsid != 0) { 2387 rc = avc_has_perm(&selinux_state, 2388 ptsid, new_tsec->sid, 2389 SECCLASS_PROCESS, 2390 PROCESS__PTRACE, NULL); 2391 if (rc) 2392 return -EPERM; 2393 } 2394 } 2395 2396 /* Clear any possibly unsafe personality bits on exec: */ 2397 bprm->per_clear |= PER_CLEAR_ON_SETID; 2398 2399 /* Enable secure mode for SIDs transitions unless 2400 the noatsecure permission is granted between 2401 the two SIDs, i.e. ahp returns 0. */ 2402 rc = avc_has_perm(&selinux_state, 2403 old_tsec->sid, new_tsec->sid, 2404 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2405 NULL); 2406 bprm->secureexec |= !!rc; 2407 } 2408 2409 return 0; 2410 } 2411 2412 static int match_file(const void *p, struct file *file, unsigned fd) 2413 { 2414 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2415 } 2416 2417 /* Derived from fs/exec.c:flush_old_files. */ 2418 static inline void flush_unauthorized_files(const struct cred *cred, 2419 struct files_struct *files) 2420 { 2421 struct file *file, *devnull = NULL; 2422 struct tty_struct *tty; 2423 int drop_tty = 0; 2424 unsigned n; 2425 2426 tty = get_current_tty(); 2427 if (tty) { 2428 spin_lock(&tty->files_lock); 2429 if (!list_empty(&tty->tty_files)) { 2430 struct tty_file_private *file_priv; 2431 2432 /* Revalidate access to controlling tty. 2433 Use file_path_has_perm on the tty path directly 2434 rather than using file_has_perm, as this particular 2435 open file may belong to another process and we are 2436 only interested in the inode-based check here. */ 2437 file_priv = list_first_entry(&tty->tty_files, 2438 struct tty_file_private, list); 2439 file = file_priv->file; 2440 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2441 drop_tty = 1; 2442 } 2443 spin_unlock(&tty->files_lock); 2444 tty_kref_put(tty); 2445 } 2446 /* Reset controlling tty. */ 2447 if (drop_tty) 2448 no_tty(); 2449 2450 /* Revalidate access to inherited open files. */ 2451 n = iterate_fd(files, 0, match_file, cred); 2452 if (!n) /* none found? */ 2453 return; 2454 2455 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2456 if (IS_ERR(devnull)) 2457 devnull = NULL; 2458 /* replace all the matching ones with this */ 2459 do { 2460 replace_fd(n - 1, devnull, 0); 2461 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2462 if (devnull) 2463 fput(devnull); 2464 } 2465 2466 /* 2467 * Prepare a process for imminent new credential changes due to exec 2468 */ 2469 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2470 { 2471 struct task_security_struct *new_tsec; 2472 struct rlimit *rlim, *initrlim; 2473 int rc, i; 2474 2475 new_tsec = selinux_cred(bprm->cred); 2476 if (new_tsec->sid == new_tsec->osid) 2477 return; 2478 2479 /* Close files for which the new task SID is not authorized. */ 2480 flush_unauthorized_files(bprm->cred, current->files); 2481 2482 /* Always clear parent death signal on SID transitions. */ 2483 current->pdeath_signal = 0; 2484 2485 /* Check whether the new SID can inherit resource limits from the old 2486 * SID. If not, reset all soft limits to the lower of the current 2487 * task's hard limit and the init task's soft limit. 2488 * 2489 * Note that the setting of hard limits (even to lower them) can be 2490 * controlled by the setrlimit check. The inclusion of the init task's 2491 * soft limit into the computation is to avoid resetting soft limits 2492 * higher than the default soft limit for cases where the default is 2493 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2494 */ 2495 rc = avc_has_perm(&selinux_state, 2496 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2497 PROCESS__RLIMITINH, NULL); 2498 if (rc) { 2499 /* protect against do_prlimit() */ 2500 task_lock(current); 2501 for (i = 0; i < RLIM_NLIMITS; i++) { 2502 rlim = current->signal->rlim + i; 2503 initrlim = init_task.signal->rlim + i; 2504 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2505 } 2506 task_unlock(current); 2507 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2508 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2509 } 2510 } 2511 2512 /* 2513 * Clean up the process immediately after the installation of new credentials 2514 * due to exec 2515 */ 2516 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2517 { 2518 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2519 u32 osid, sid; 2520 int rc; 2521 2522 osid = tsec->osid; 2523 sid = tsec->sid; 2524 2525 if (sid == osid) 2526 return; 2527 2528 /* Check whether the new SID can inherit signal state from the old SID. 2529 * If not, clear itimers to avoid subsequent signal generation and 2530 * flush and unblock signals. 2531 * 2532 * This must occur _after_ the task SID has been updated so that any 2533 * kill done after the flush will be checked against the new SID. 2534 */ 2535 rc = avc_has_perm(&selinux_state, 2536 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2537 if (rc) { 2538 clear_itimer(); 2539 2540 spin_lock_irq(¤t->sighand->siglock); 2541 if (!fatal_signal_pending(current)) { 2542 flush_sigqueue(¤t->pending); 2543 flush_sigqueue(¤t->signal->shared_pending); 2544 flush_signal_handlers(current, 1); 2545 sigemptyset(¤t->blocked); 2546 recalc_sigpending(); 2547 } 2548 spin_unlock_irq(¤t->sighand->siglock); 2549 } 2550 2551 /* Wake up the parent if it is waiting so that it can recheck 2552 * wait permission to the new task SID. */ 2553 read_lock(&tasklist_lock); 2554 __wake_up_parent(current, current->real_parent); 2555 read_unlock(&tasklist_lock); 2556 } 2557 2558 /* superblock security operations */ 2559 2560 static int selinux_sb_alloc_security(struct super_block *sb) 2561 { 2562 struct superblock_security_struct *sbsec; 2563 2564 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 2565 if (!sbsec) 2566 return -ENOMEM; 2567 2568 mutex_init(&sbsec->lock); 2569 INIT_LIST_HEAD(&sbsec->isec_head); 2570 spin_lock_init(&sbsec->isec_lock); 2571 sbsec->sid = SECINITSID_UNLABELED; 2572 sbsec->def_sid = SECINITSID_FILE; 2573 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2574 sb->s_security = sbsec; 2575 2576 return 0; 2577 } 2578 2579 static void selinux_sb_free_security(struct super_block *sb) 2580 { 2581 superblock_free_security(sb); 2582 } 2583 2584 static inline int opt_len(const char *s) 2585 { 2586 bool open_quote = false; 2587 int len; 2588 char c; 2589 2590 for (len = 0; (c = s[len]) != '\0'; len++) { 2591 if (c == '"') 2592 open_quote = !open_quote; 2593 if (c == ',' && !open_quote) 2594 break; 2595 } 2596 return len; 2597 } 2598 2599 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2600 { 2601 char *from = options; 2602 char *to = options; 2603 bool first = true; 2604 int rc; 2605 2606 while (1) { 2607 int len = opt_len(from); 2608 int token; 2609 char *arg = NULL; 2610 2611 token = match_opt_prefix(from, len, &arg); 2612 2613 if (token != Opt_error) { 2614 char *p, *q; 2615 2616 /* strip quotes */ 2617 if (arg) { 2618 for (p = q = arg; p < from + len; p++) { 2619 char c = *p; 2620 if (c != '"') 2621 *q++ = c; 2622 } 2623 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2624 if (!arg) { 2625 rc = -ENOMEM; 2626 goto free_opt; 2627 } 2628 } 2629 rc = selinux_add_opt(token, arg, mnt_opts); 2630 if (unlikely(rc)) { 2631 kfree(arg); 2632 goto free_opt; 2633 } 2634 } else { 2635 if (!first) { // copy with preceding comma 2636 from--; 2637 len++; 2638 } 2639 if (to != from) 2640 memmove(to, from, len); 2641 to += len; 2642 first = false; 2643 } 2644 if (!from[len]) 2645 break; 2646 from += len + 1; 2647 } 2648 *to = '\0'; 2649 return 0; 2650 2651 free_opt: 2652 if (*mnt_opts) { 2653 selinux_free_mnt_opts(*mnt_opts); 2654 *mnt_opts = NULL; 2655 } 2656 return rc; 2657 } 2658 2659 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2660 { 2661 struct selinux_mnt_opts *opts = mnt_opts; 2662 struct superblock_security_struct *sbsec = sb->s_security; 2663 u32 sid; 2664 int rc; 2665 2666 if (!(sbsec->flags & SE_SBINITIALIZED)) 2667 return 0; 2668 2669 if (!opts) 2670 return 0; 2671 2672 if (opts->fscontext) { 2673 rc = parse_sid(sb, opts->fscontext, &sid); 2674 if (rc) 2675 return rc; 2676 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2677 goto out_bad_option; 2678 } 2679 if (opts->context) { 2680 rc = parse_sid(sb, opts->context, &sid); 2681 if (rc) 2682 return rc; 2683 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2684 goto out_bad_option; 2685 } 2686 if (opts->rootcontext) { 2687 struct inode_security_struct *root_isec; 2688 root_isec = backing_inode_security(sb->s_root); 2689 rc = parse_sid(sb, opts->rootcontext, &sid); 2690 if (rc) 2691 return rc; 2692 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2693 goto out_bad_option; 2694 } 2695 if (opts->defcontext) { 2696 rc = parse_sid(sb, opts->defcontext, &sid); 2697 if (rc) 2698 return rc; 2699 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2700 goto out_bad_option; 2701 } 2702 return 0; 2703 2704 out_bad_option: 2705 pr_warn("SELinux: unable to change security options " 2706 "during remount (dev %s, type=%s)\n", sb->s_id, 2707 sb->s_type->name); 2708 return -EINVAL; 2709 } 2710 2711 static int selinux_sb_kern_mount(struct super_block *sb) 2712 { 2713 const struct cred *cred = current_cred(); 2714 struct common_audit_data ad; 2715 2716 ad.type = LSM_AUDIT_DATA_DENTRY; 2717 ad.u.dentry = sb->s_root; 2718 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2719 } 2720 2721 static int selinux_sb_statfs(struct dentry *dentry) 2722 { 2723 const struct cred *cred = current_cred(); 2724 struct common_audit_data ad; 2725 2726 ad.type = LSM_AUDIT_DATA_DENTRY; 2727 ad.u.dentry = dentry->d_sb->s_root; 2728 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2729 } 2730 2731 static int selinux_mount(const char *dev_name, 2732 const struct path *path, 2733 const char *type, 2734 unsigned long flags, 2735 void *data) 2736 { 2737 const struct cred *cred = current_cred(); 2738 2739 if (flags & MS_REMOUNT) 2740 return superblock_has_perm(cred, path->dentry->d_sb, 2741 FILESYSTEM__REMOUNT, NULL); 2742 else 2743 return path_has_perm(cred, path, FILE__MOUNTON); 2744 } 2745 2746 static int selinux_move_mount(const struct path *from_path, 2747 const struct path *to_path) 2748 { 2749 const struct cred *cred = current_cred(); 2750 2751 return path_has_perm(cred, to_path, FILE__MOUNTON); 2752 } 2753 2754 static int selinux_umount(struct vfsmount *mnt, int flags) 2755 { 2756 const struct cred *cred = current_cred(); 2757 2758 return superblock_has_perm(cred, mnt->mnt_sb, 2759 FILESYSTEM__UNMOUNT, NULL); 2760 } 2761 2762 static int selinux_fs_context_dup(struct fs_context *fc, 2763 struct fs_context *src_fc) 2764 { 2765 const struct selinux_mnt_opts *src = src_fc->security; 2766 struct selinux_mnt_opts *opts; 2767 2768 if (!src) 2769 return 0; 2770 2771 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 2772 if (!fc->security) 2773 return -ENOMEM; 2774 2775 opts = fc->security; 2776 2777 if (src->fscontext) { 2778 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); 2779 if (!opts->fscontext) 2780 return -ENOMEM; 2781 } 2782 if (src->context) { 2783 opts->context = kstrdup(src->context, GFP_KERNEL); 2784 if (!opts->context) 2785 return -ENOMEM; 2786 } 2787 if (src->rootcontext) { 2788 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); 2789 if (!opts->rootcontext) 2790 return -ENOMEM; 2791 } 2792 if (src->defcontext) { 2793 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); 2794 if (!opts->defcontext) 2795 return -ENOMEM; 2796 } 2797 return 0; 2798 } 2799 2800 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2801 fsparam_string(CONTEXT_STR, Opt_context), 2802 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2803 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2804 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2805 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2806 {} 2807 }; 2808 2809 static int selinux_fs_context_parse_param(struct fs_context *fc, 2810 struct fs_parameter *param) 2811 { 2812 struct fs_parse_result result; 2813 int opt, rc; 2814 2815 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2816 if (opt < 0) 2817 return opt; 2818 2819 rc = selinux_add_opt(opt, param->string, &fc->security); 2820 if (!rc) { 2821 param->string = NULL; 2822 rc = 1; 2823 } 2824 return rc; 2825 } 2826 2827 /* inode security operations */ 2828 2829 static int selinux_inode_alloc_security(struct inode *inode) 2830 { 2831 struct inode_security_struct *isec = selinux_inode(inode); 2832 u32 sid = current_sid(); 2833 2834 spin_lock_init(&isec->lock); 2835 INIT_LIST_HEAD(&isec->list); 2836 isec->inode = inode; 2837 isec->sid = SECINITSID_UNLABELED; 2838 isec->sclass = SECCLASS_FILE; 2839 isec->task_sid = sid; 2840 isec->initialized = LABEL_INVALID; 2841 2842 return 0; 2843 } 2844 2845 static void selinux_inode_free_security(struct inode *inode) 2846 { 2847 inode_free_security(inode); 2848 } 2849 2850 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2851 const struct qstr *name, void **ctx, 2852 u32 *ctxlen) 2853 { 2854 u32 newsid; 2855 int rc; 2856 2857 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2858 d_inode(dentry->d_parent), name, 2859 inode_mode_to_security_class(mode), 2860 &newsid); 2861 if (rc) 2862 return rc; 2863 2864 return security_sid_to_context(&selinux_state, newsid, (char **)ctx, 2865 ctxlen); 2866 } 2867 2868 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2869 struct qstr *name, 2870 const struct cred *old, 2871 struct cred *new) 2872 { 2873 u32 newsid; 2874 int rc; 2875 struct task_security_struct *tsec; 2876 2877 rc = selinux_determine_inode_label(selinux_cred(old), 2878 d_inode(dentry->d_parent), name, 2879 inode_mode_to_security_class(mode), 2880 &newsid); 2881 if (rc) 2882 return rc; 2883 2884 tsec = selinux_cred(new); 2885 tsec->create_sid = newsid; 2886 return 0; 2887 } 2888 2889 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2890 const struct qstr *qstr, 2891 const char **name, 2892 void **value, size_t *len) 2893 { 2894 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2895 struct superblock_security_struct *sbsec; 2896 u32 newsid, clen; 2897 int rc; 2898 char *context; 2899 2900 sbsec = dir->i_sb->s_security; 2901 2902 newsid = tsec->create_sid; 2903 2904 rc = selinux_determine_inode_label(tsec, dir, qstr, 2905 inode_mode_to_security_class(inode->i_mode), 2906 &newsid); 2907 if (rc) 2908 return rc; 2909 2910 /* Possibly defer initialization to selinux_complete_init. */ 2911 if (sbsec->flags & SE_SBINITIALIZED) { 2912 struct inode_security_struct *isec = selinux_inode(inode); 2913 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2914 isec->sid = newsid; 2915 isec->initialized = LABEL_INITIALIZED; 2916 } 2917 2918 if (!selinux_initialized(&selinux_state) || 2919 !(sbsec->flags & SBLABEL_MNT)) 2920 return -EOPNOTSUPP; 2921 2922 if (name) 2923 *name = XATTR_SELINUX_SUFFIX; 2924 2925 if (value && len) { 2926 rc = security_sid_to_context_force(&selinux_state, newsid, 2927 &context, &clen); 2928 if (rc) 2929 return rc; 2930 *value = context; 2931 *len = clen; 2932 } 2933 2934 return 0; 2935 } 2936 2937 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 2938 { 2939 return may_create(dir, dentry, SECCLASS_FILE); 2940 } 2941 2942 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2943 { 2944 return may_link(dir, old_dentry, MAY_LINK); 2945 } 2946 2947 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2948 { 2949 return may_link(dir, dentry, MAY_UNLINK); 2950 } 2951 2952 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2953 { 2954 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2955 } 2956 2957 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 2958 { 2959 return may_create(dir, dentry, SECCLASS_DIR); 2960 } 2961 2962 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2963 { 2964 return may_link(dir, dentry, MAY_RMDIR); 2965 } 2966 2967 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 2968 { 2969 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2970 } 2971 2972 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2973 struct inode *new_inode, struct dentry *new_dentry) 2974 { 2975 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2976 } 2977 2978 static int selinux_inode_readlink(struct dentry *dentry) 2979 { 2980 const struct cred *cred = current_cred(); 2981 2982 return dentry_has_perm(cred, dentry, FILE__READ); 2983 } 2984 2985 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 2986 bool rcu) 2987 { 2988 const struct cred *cred = current_cred(); 2989 struct common_audit_data ad; 2990 struct inode_security_struct *isec; 2991 u32 sid; 2992 2993 validate_creds(cred); 2994 2995 ad.type = LSM_AUDIT_DATA_DENTRY; 2996 ad.u.dentry = dentry; 2997 sid = cred_sid(cred); 2998 isec = inode_security_rcu(inode, rcu); 2999 if (IS_ERR(isec)) 3000 return PTR_ERR(isec); 3001 3002 return avc_has_perm_flags(&selinux_state, 3003 sid, isec->sid, isec->sclass, FILE__READ, &ad, 3004 rcu ? MAY_NOT_BLOCK : 0); 3005 } 3006 3007 static noinline int audit_inode_permission(struct inode *inode, 3008 u32 perms, u32 audited, u32 denied, 3009 int result) 3010 { 3011 struct common_audit_data ad; 3012 struct inode_security_struct *isec = selinux_inode(inode); 3013 int rc; 3014 3015 ad.type = LSM_AUDIT_DATA_INODE; 3016 ad.u.inode = inode; 3017 3018 rc = slow_avc_audit(&selinux_state, 3019 current_sid(), isec->sid, isec->sclass, perms, 3020 audited, denied, result, &ad); 3021 if (rc) 3022 return rc; 3023 return 0; 3024 } 3025 3026 static int selinux_inode_permission(struct inode *inode, int mask) 3027 { 3028 const struct cred *cred = current_cred(); 3029 u32 perms; 3030 bool from_access; 3031 bool no_block = mask & MAY_NOT_BLOCK; 3032 struct inode_security_struct *isec; 3033 u32 sid; 3034 struct av_decision avd; 3035 int rc, rc2; 3036 u32 audited, denied; 3037 3038 from_access = mask & MAY_ACCESS; 3039 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3040 3041 /* No permission to check. Existence test. */ 3042 if (!mask) 3043 return 0; 3044 3045 validate_creds(cred); 3046 3047 if (unlikely(IS_PRIVATE(inode))) 3048 return 0; 3049 3050 perms = file_mask_to_av(inode->i_mode, mask); 3051 3052 sid = cred_sid(cred); 3053 isec = inode_security_rcu(inode, no_block); 3054 if (IS_ERR(isec)) 3055 return PTR_ERR(isec); 3056 3057 rc = avc_has_perm_noaudit(&selinux_state, 3058 sid, isec->sid, isec->sclass, perms, 3059 no_block ? AVC_NONBLOCKING : 0, 3060 &avd); 3061 audited = avc_audit_required(perms, &avd, rc, 3062 from_access ? FILE__AUDIT_ACCESS : 0, 3063 &denied); 3064 if (likely(!audited)) 3065 return rc; 3066 3067 /* fall back to ref-walk if we have to generate audit */ 3068 if (no_block) 3069 return -ECHILD; 3070 3071 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3072 if (rc2) 3073 return rc2; 3074 return rc; 3075 } 3076 3077 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3078 { 3079 const struct cred *cred = current_cred(); 3080 struct inode *inode = d_backing_inode(dentry); 3081 unsigned int ia_valid = iattr->ia_valid; 3082 __u32 av = FILE__WRITE; 3083 3084 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3085 if (ia_valid & ATTR_FORCE) { 3086 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3087 ATTR_FORCE); 3088 if (!ia_valid) 3089 return 0; 3090 } 3091 3092 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3093 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3094 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3095 3096 if (selinux_policycap_openperm() && 3097 inode->i_sb->s_magic != SOCKFS_MAGIC && 3098 (ia_valid & ATTR_SIZE) && 3099 !(ia_valid & ATTR_FILE)) 3100 av |= FILE__OPEN; 3101 3102 return dentry_has_perm(cred, dentry, av); 3103 } 3104 3105 static int selinux_inode_getattr(const struct path *path) 3106 { 3107 return path_has_perm(current_cred(), path, FILE__GETATTR); 3108 } 3109 3110 static bool has_cap_mac_admin(bool audit) 3111 { 3112 const struct cred *cred = current_cred(); 3113 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3114 3115 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3116 return false; 3117 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3118 return false; 3119 return true; 3120 } 3121 3122 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 3123 const void *value, size_t size, int flags) 3124 { 3125 struct inode *inode = d_backing_inode(dentry); 3126 struct inode_security_struct *isec; 3127 struct superblock_security_struct *sbsec; 3128 struct common_audit_data ad; 3129 u32 newsid, sid = current_sid(); 3130 int rc = 0; 3131 3132 if (strcmp(name, XATTR_NAME_SELINUX)) { 3133 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3134 if (rc) 3135 return rc; 3136 3137 /* Not an attribute we recognize, so just check the 3138 ordinary setattr permission. */ 3139 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3140 } 3141 3142 if (!selinux_initialized(&selinux_state)) 3143 return (inode_owner_or_capable(inode) ? 0 : -EPERM); 3144 3145 sbsec = inode->i_sb->s_security; 3146 if (!(sbsec->flags & SBLABEL_MNT)) 3147 return -EOPNOTSUPP; 3148 3149 if (!inode_owner_or_capable(inode)) 3150 return -EPERM; 3151 3152 ad.type = LSM_AUDIT_DATA_DENTRY; 3153 ad.u.dentry = dentry; 3154 3155 isec = backing_inode_security(dentry); 3156 rc = avc_has_perm(&selinux_state, 3157 sid, isec->sid, isec->sclass, 3158 FILE__RELABELFROM, &ad); 3159 if (rc) 3160 return rc; 3161 3162 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3163 GFP_KERNEL); 3164 if (rc == -EINVAL) { 3165 if (!has_cap_mac_admin(true)) { 3166 struct audit_buffer *ab; 3167 size_t audit_size; 3168 3169 /* We strip a nul only if it is at the end, otherwise the 3170 * context contains a nul and we should audit that */ 3171 if (value) { 3172 const char *str = value; 3173 3174 if (str[size - 1] == '\0') 3175 audit_size = size - 1; 3176 else 3177 audit_size = size; 3178 } else { 3179 audit_size = 0; 3180 } 3181 ab = audit_log_start(audit_context(), 3182 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3183 audit_log_format(ab, "op=setxattr invalid_context="); 3184 audit_log_n_untrustedstring(ab, value, audit_size); 3185 audit_log_end(ab); 3186 3187 return rc; 3188 } 3189 rc = security_context_to_sid_force(&selinux_state, value, 3190 size, &newsid); 3191 } 3192 if (rc) 3193 return rc; 3194 3195 rc = avc_has_perm(&selinux_state, 3196 sid, newsid, isec->sclass, 3197 FILE__RELABELTO, &ad); 3198 if (rc) 3199 return rc; 3200 3201 rc = security_validate_transition(&selinux_state, isec->sid, newsid, 3202 sid, isec->sclass); 3203 if (rc) 3204 return rc; 3205 3206 return avc_has_perm(&selinux_state, 3207 newsid, 3208 sbsec->sid, 3209 SECCLASS_FILESYSTEM, 3210 FILESYSTEM__ASSOCIATE, 3211 &ad); 3212 } 3213 3214 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3215 const void *value, size_t size, 3216 int flags) 3217 { 3218 struct inode *inode = d_backing_inode(dentry); 3219 struct inode_security_struct *isec; 3220 u32 newsid; 3221 int rc; 3222 3223 if (strcmp(name, XATTR_NAME_SELINUX)) { 3224 /* Not an attribute we recognize, so nothing to do. */ 3225 return; 3226 } 3227 3228 if (!selinux_initialized(&selinux_state)) { 3229 /* If we haven't even been initialized, then we can't validate 3230 * against a policy, so leave the label as invalid. It may 3231 * resolve to a valid label on the next revalidation try if 3232 * we've since initialized. 3233 */ 3234 return; 3235 } 3236 3237 rc = security_context_to_sid_force(&selinux_state, value, size, 3238 &newsid); 3239 if (rc) { 3240 pr_err("SELinux: unable to map context to SID" 3241 "for (%s, %lu), rc=%d\n", 3242 inode->i_sb->s_id, inode->i_ino, -rc); 3243 return; 3244 } 3245 3246 isec = backing_inode_security(dentry); 3247 spin_lock(&isec->lock); 3248 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3249 isec->sid = newsid; 3250 isec->initialized = LABEL_INITIALIZED; 3251 spin_unlock(&isec->lock); 3252 3253 return; 3254 } 3255 3256 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3257 { 3258 const struct cred *cred = current_cred(); 3259 3260 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3261 } 3262 3263 static int selinux_inode_listxattr(struct dentry *dentry) 3264 { 3265 const struct cred *cred = current_cred(); 3266 3267 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3268 } 3269 3270 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 3271 { 3272 if (strcmp(name, XATTR_NAME_SELINUX)) { 3273 int rc = cap_inode_removexattr(dentry, name); 3274 if (rc) 3275 return rc; 3276 3277 /* Not an attribute we recognize, so just check the 3278 ordinary setattr permission. */ 3279 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3280 } 3281 3282 if (!selinux_initialized(&selinux_state)) 3283 return 0; 3284 3285 /* No one is allowed to remove a SELinux security label. 3286 You can change the label, but all data must be labeled. */ 3287 return -EACCES; 3288 } 3289 3290 static int selinux_path_notify(const struct path *path, u64 mask, 3291 unsigned int obj_type) 3292 { 3293 int ret; 3294 u32 perm; 3295 3296 struct common_audit_data ad; 3297 3298 ad.type = LSM_AUDIT_DATA_PATH; 3299 ad.u.path = *path; 3300 3301 /* 3302 * Set permission needed based on the type of mark being set. 3303 * Performs an additional check for sb watches. 3304 */ 3305 switch (obj_type) { 3306 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3307 perm = FILE__WATCH_MOUNT; 3308 break; 3309 case FSNOTIFY_OBJ_TYPE_SB: 3310 perm = FILE__WATCH_SB; 3311 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3312 FILESYSTEM__WATCH, &ad); 3313 if (ret) 3314 return ret; 3315 break; 3316 case FSNOTIFY_OBJ_TYPE_INODE: 3317 perm = FILE__WATCH; 3318 break; 3319 default: 3320 return -EINVAL; 3321 } 3322 3323 /* blocking watches require the file:watch_with_perm permission */ 3324 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3325 perm |= FILE__WATCH_WITH_PERM; 3326 3327 /* watches on read-like events need the file:watch_reads permission */ 3328 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3329 perm |= FILE__WATCH_READS; 3330 3331 return path_has_perm(current_cred(), path, perm); 3332 } 3333 3334 /* 3335 * Copy the inode security context value to the user. 3336 * 3337 * Permission check is handled by selinux_inode_getxattr hook. 3338 */ 3339 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) 3340 { 3341 u32 size; 3342 int error; 3343 char *context = NULL; 3344 struct inode_security_struct *isec; 3345 3346 /* 3347 * If we're not initialized yet, then we can't validate contexts, so 3348 * just let vfs_getxattr fall back to using the on-disk xattr. 3349 */ 3350 if (!selinux_initialized(&selinux_state) || 3351 strcmp(name, XATTR_SELINUX_SUFFIX)) 3352 return -EOPNOTSUPP; 3353 3354 /* 3355 * If the caller has CAP_MAC_ADMIN, then get the raw context 3356 * value even if it is not defined by current policy; otherwise, 3357 * use the in-core value under current policy. 3358 * Use the non-auditing forms of the permission checks since 3359 * getxattr may be called by unprivileged processes commonly 3360 * and lack of permission just means that we fall back to the 3361 * in-core context value, not a denial. 3362 */ 3363 isec = inode_security(inode); 3364 if (has_cap_mac_admin(false)) 3365 error = security_sid_to_context_force(&selinux_state, 3366 isec->sid, &context, 3367 &size); 3368 else 3369 error = security_sid_to_context(&selinux_state, isec->sid, 3370 &context, &size); 3371 if (error) 3372 return error; 3373 error = size; 3374 if (alloc) { 3375 *buffer = context; 3376 goto out_nofree; 3377 } 3378 kfree(context); 3379 out_nofree: 3380 return error; 3381 } 3382 3383 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3384 const void *value, size_t size, int flags) 3385 { 3386 struct inode_security_struct *isec = inode_security_novalidate(inode); 3387 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 3388 u32 newsid; 3389 int rc; 3390 3391 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3392 return -EOPNOTSUPP; 3393 3394 if (!(sbsec->flags & SBLABEL_MNT)) 3395 return -EOPNOTSUPP; 3396 3397 if (!value || !size) 3398 return -EACCES; 3399 3400 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3401 GFP_KERNEL); 3402 if (rc) 3403 return rc; 3404 3405 spin_lock(&isec->lock); 3406 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3407 isec->sid = newsid; 3408 isec->initialized = LABEL_INITIALIZED; 3409 spin_unlock(&isec->lock); 3410 return 0; 3411 } 3412 3413 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3414 { 3415 const int len = sizeof(XATTR_NAME_SELINUX); 3416 if (buffer && len <= buffer_size) 3417 memcpy(buffer, XATTR_NAME_SELINUX, len); 3418 return len; 3419 } 3420 3421 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3422 { 3423 struct inode_security_struct *isec = inode_security_novalidate(inode); 3424 *secid = isec->sid; 3425 } 3426 3427 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3428 { 3429 u32 sid; 3430 struct task_security_struct *tsec; 3431 struct cred *new_creds = *new; 3432 3433 if (new_creds == NULL) { 3434 new_creds = prepare_creds(); 3435 if (!new_creds) 3436 return -ENOMEM; 3437 } 3438 3439 tsec = selinux_cred(new_creds); 3440 /* Get label from overlay inode and set it in create_sid */ 3441 selinux_inode_getsecid(d_inode(src), &sid); 3442 tsec->create_sid = sid; 3443 *new = new_creds; 3444 return 0; 3445 } 3446 3447 static int selinux_inode_copy_up_xattr(const char *name) 3448 { 3449 /* The copy_up hook above sets the initial context on an inode, but we 3450 * don't then want to overwrite it by blindly copying all the lower 3451 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3452 */ 3453 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3454 return 1; /* Discard */ 3455 /* 3456 * Any other attribute apart from SELINUX is not claimed, supported 3457 * by selinux. 3458 */ 3459 return -EOPNOTSUPP; 3460 } 3461 3462 /* kernfs node operations */ 3463 3464 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3465 struct kernfs_node *kn) 3466 { 3467 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3468 u32 parent_sid, newsid, clen; 3469 int rc; 3470 char *context; 3471 3472 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3473 if (rc == -ENODATA) 3474 return 0; 3475 else if (rc < 0) 3476 return rc; 3477 3478 clen = (u32)rc; 3479 context = kmalloc(clen, GFP_KERNEL); 3480 if (!context) 3481 return -ENOMEM; 3482 3483 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3484 if (rc < 0) { 3485 kfree(context); 3486 return rc; 3487 } 3488 3489 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, 3490 GFP_KERNEL); 3491 kfree(context); 3492 if (rc) 3493 return rc; 3494 3495 if (tsec->create_sid) { 3496 newsid = tsec->create_sid; 3497 } else { 3498 u16 secclass = inode_mode_to_security_class(kn->mode); 3499 struct qstr q; 3500 3501 q.name = kn->name; 3502 q.hash_len = hashlen_string(kn_dir, kn->name); 3503 3504 rc = security_transition_sid(&selinux_state, tsec->sid, 3505 parent_sid, secclass, &q, 3506 &newsid); 3507 if (rc) 3508 return rc; 3509 } 3510 3511 rc = security_sid_to_context_force(&selinux_state, newsid, 3512 &context, &clen); 3513 if (rc) 3514 return rc; 3515 3516 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3517 XATTR_CREATE); 3518 kfree(context); 3519 return rc; 3520 } 3521 3522 3523 /* file security operations */ 3524 3525 static int selinux_revalidate_file_permission(struct file *file, int mask) 3526 { 3527 const struct cred *cred = current_cred(); 3528 struct inode *inode = file_inode(file); 3529 3530 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3531 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3532 mask |= MAY_APPEND; 3533 3534 return file_has_perm(cred, file, 3535 file_mask_to_av(inode->i_mode, mask)); 3536 } 3537 3538 static int selinux_file_permission(struct file *file, int mask) 3539 { 3540 struct inode *inode = file_inode(file); 3541 struct file_security_struct *fsec = selinux_file(file); 3542 struct inode_security_struct *isec; 3543 u32 sid = current_sid(); 3544 3545 if (!mask) 3546 /* No permission to check. Existence test. */ 3547 return 0; 3548 3549 isec = inode_security(inode); 3550 if (sid == fsec->sid && fsec->isid == isec->sid && 3551 fsec->pseqno == avc_policy_seqno(&selinux_state)) 3552 /* No change since file_open check. */ 3553 return 0; 3554 3555 return selinux_revalidate_file_permission(file, mask); 3556 } 3557 3558 static int selinux_file_alloc_security(struct file *file) 3559 { 3560 struct file_security_struct *fsec = selinux_file(file); 3561 u32 sid = current_sid(); 3562 3563 fsec->sid = sid; 3564 fsec->fown_sid = sid; 3565 3566 return 0; 3567 } 3568 3569 /* 3570 * Check whether a task has the ioctl permission and cmd 3571 * operation to an inode. 3572 */ 3573 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3574 u32 requested, u16 cmd) 3575 { 3576 struct common_audit_data ad; 3577 struct file_security_struct *fsec = selinux_file(file); 3578 struct inode *inode = file_inode(file); 3579 struct inode_security_struct *isec; 3580 struct lsm_ioctlop_audit ioctl; 3581 u32 ssid = cred_sid(cred); 3582 int rc; 3583 u8 driver = cmd >> 8; 3584 u8 xperm = cmd & 0xff; 3585 3586 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3587 ad.u.op = &ioctl; 3588 ad.u.op->cmd = cmd; 3589 ad.u.op->path = file->f_path; 3590 3591 if (ssid != fsec->sid) { 3592 rc = avc_has_perm(&selinux_state, 3593 ssid, fsec->sid, 3594 SECCLASS_FD, 3595 FD__USE, 3596 &ad); 3597 if (rc) 3598 goto out; 3599 } 3600 3601 if (unlikely(IS_PRIVATE(inode))) 3602 return 0; 3603 3604 isec = inode_security(inode); 3605 rc = avc_has_extended_perms(&selinux_state, 3606 ssid, isec->sid, isec->sclass, 3607 requested, driver, xperm, &ad); 3608 out: 3609 return rc; 3610 } 3611 3612 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3613 unsigned long arg) 3614 { 3615 const struct cred *cred = current_cred(); 3616 int error = 0; 3617 3618 switch (cmd) { 3619 case FIONREAD: 3620 case FIBMAP: 3621 case FIGETBSZ: 3622 case FS_IOC_GETFLAGS: 3623 case FS_IOC_GETVERSION: 3624 error = file_has_perm(cred, file, FILE__GETATTR); 3625 break; 3626 3627 case FS_IOC_SETFLAGS: 3628 case FS_IOC_SETVERSION: 3629 error = file_has_perm(cred, file, FILE__SETATTR); 3630 break; 3631 3632 /* sys_ioctl() checks */ 3633 case FIONBIO: 3634 case FIOASYNC: 3635 error = file_has_perm(cred, file, 0); 3636 break; 3637 3638 case KDSKBENT: 3639 case KDSKBSENT: 3640 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3641 CAP_OPT_NONE, true); 3642 break; 3643 3644 /* default case assumes that the command will go 3645 * to the file's ioctl() function. 3646 */ 3647 default: 3648 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3649 } 3650 return error; 3651 } 3652 3653 static int default_noexec __ro_after_init; 3654 3655 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3656 { 3657 const struct cred *cred = current_cred(); 3658 u32 sid = cred_sid(cred); 3659 int rc = 0; 3660 3661 if (default_noexec && 3662 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3663 (!shared && (prot & PROT_WRITE)))) { 3664 /* 3665 * We are making executable an anonymous mapping or a 3666 * private file mapping that will also be writable. 3667 * This has an additional check. 3668 */ 3669 rc = avc_has_perm(&selinux_state, 3670 sid, sid, SECCLASS_PROCESS, 3671 PROCESS__EXECMEM, NULL); 3672 if (rc) 3673 goto error; 3674 } 3675 3676 if (file) { 3677 /* read access is always possible with a mapping */ 3678 u32 av = FILE__READ; 3679 3680 /* write access only matters if the mapping is shared */ 3681 if (shared && (prot & PROT_WRITE)) 3682 av |= FILE__WRITE; 3683 3684 if (prot & PROT_EXEC) 3685 av |= FILE__EXECUTE; 3686 3687 return file_has_perm(cred, file, av); 3688 } 3689 3690 error: 3691 return rc; 3692 } 3693 3694 static int selinux_mmap_addr(unsigned long addr) 3695 { 3696 int rc = 0; 3697 3698 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3699 u32 sid = current_sid(); 3700 rc = avc_has_perm(&selinux_state, 3701 sid, sid, SECCLASS_MEMPROTECT, 3702 MEMPROTECT__MMAP_ZERO, NULL); 3703 } 3704 3705 return rc; 3706 } 3707 3708 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3709 unsigned long prot, unsigned long flags) 3710 { 3711 struct common_audit_data ad; 3712 int rc; 3713 3714 if (file) { 3715 ad.type = LSM_AUDIT_DATA_FILE; 3716 ad.u.file = file; 3717 rc = inode_has_perm(current_cred(), file_inode(file), 3718 FILE__MAP, &ad); 3719 if (rc) 3720 return rc; 3721 } 3722 3723 if (checkreqprot_get(&selinux_state)) 3724 prot = reqprot; 3725 3726 return file_map_prot_check(file, prot, 3727 (flags & MAP_TYPE) == MAP_SHARED); 3728 } 3729 3730 static int selinux_file_mprotect(struct vm_area_struct *vma, 3731 unsigned long reqprot, 3732 unsigned long prot) 3733 { 3734 const struct cred *cred = current_cred(); 3735 u32 sid = cred_sid(cred); 3736 3737 if (checkreqprot_get(&selinux_state)) 3738 prot = reqprot; 3739 3740 if (default_noexec && 3741 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3742 int rc = 0; 3743 if (vma->vm_start >= vma->vm_mm->start_brk && 3744 vma->vm_end <= vma->vm_mm->brk) { 3745 rc = avc_has_perm(&selinux_state, 3746 sid, sid, SECCLASS_PROCESS, 3747 PROCESS__EXECHEAP, NULL); 3748 } else if (!vma->vm_file && 3749 ((vma->vm_start <= vma->vm_mm->start_stack && 3750 vma->vm_end >= vma->vm_mm->start_stack) || 3751 vma_is_stack_for_current(vma))) { 3752 rc = avc_has_perm(&selinux_state, 3753 sid, sid, SECCLASS_PROCESS, 3754 PROCESS__EXECSTACK, NULL); 3755 } else if (vma->vm_file && vma->anon_vma) { 3756 /* 3757 * We are making executable a file mapping that has 3758 * had some COW done. Since pages might have been 3759 * written, check ability to execute the possibly 3760 * modified content. This typically should only 3761 * occur for text relocations. 3762 */ 3763 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3764 } 3765 if (rc) 3766 return rc; 3767 } 3768 3769 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3770 } 3771 3772 static int selinux_file_lock(struct file *file, unsigned int cmd) 3773 { 3774 const struct cred *cred = current_cred(); 3775 3776 return file_has_perm(cred, file, FILE__LOCK); 3777 } 3778 3779 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3780 unsigned long arg) 3781 { 3782 const struct cred *cred = current_cred(); 3783 int err = 0; 3784 3785 switch (cmd) { 3786 case F_SETFL: 3787 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3788 err = file_has_perm(cred, file, FILE__WRITE); 3789 break; 3790 } 3791 fallthrough; 3792 case F_SETOWN: 3793 case F_SETSIG: 3794 case F_GETFL: 3795 case F_GETOWN: 3796 case F_GETSIG: 3797 case F_GETOWNER_UIDS: 3798 /* Just check FD__USE permission */ 3799 err = file_has_perm(cred, file, 0); 3800 break; 3801 case F_GETLK: 3802 case F_SETLK: 3803 case F_SETLKW: 3804 case F_OFD_GETLK: 3805 case F_OFD_SETLK: 3806 case F_OFD_SETLKW: 3807 #if BITS_PER_LONG == 32 3808 case F_GETLK64: 3809 case F_SETLK64: 3810 case F_SETLKW64: 3811 #endif 3812 err = file_has_perm(cred, file, FILE__LOCK); 3813 break; 3814 } 3815 3816 return err; 3817 } 3818 3819 static void selinux_file_set_fowner(struct file *file) 3820 { 3821 struct file_security_struct *fsec; 3822 3823 fsec = selinux_file(file); 3824 fsec->fown_sid = current_sid(); 3825 } 3826 3827 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3828 struct fown_struct *fown, int signum) 3829 { 3830 struct file *file; 3831 u32 sid = task_sid(tsk); 3832 u32 perm; 3833 struct file_security_struct *fsec; 3834 3835 /* struct fown_struct is never outside the context of a struct file */ 3836 file = container_of(fown, struct file, f_owner); 3837 3838 fsec = selinux_file(file); 3839 3840 if (!signum) 3841 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3842 else 3843 perm = signal_to_av(signum); 3844 3845 return avc_has_perm(&selinux_state, 3846 fsec->fown_sid, sid, 3847 SECCLASS_PROCESS, perm, NULL); 3848 } 3849 3850 static int selinux_file_receive(struct file *file) 3851 { 3852 const struct cred *cred = current_cred(); 3853 3854 return file_has_perm(cred, file, file_to_av(file)); 3855 } 3856 3857 static int selinux_file_open(struct file *file) 3858 { 3859 struct file_security_struct *fsec; 3860 struct inode_security_struct *isec; 3861 3862 fsec = selinux_file(file); 3863 isec = inode_security(file_inode(file)); 3864 /* 3865 * Save inode label and policy sequence number 3866 * at open-time so that selinux_file_permission 3867 * can determine whether revalidation is necessary. 3868 * Task label is already saved in the file security 3869 * struct as its SID. 3870 */ 3871 fsec->isid = isec->sid; 3872 fsec->pseqno = avc_policy_seqno(&selinux_state); 3873 /* 3874 * Since the inode label or policy seqno may have changed 3875 * between the selinux_inode_permission check and the saving 3876 * of state above, recheck that access is still permitted. 3877 * Otherwise, access might never be revalidated against the 3878 * new inode label or new policy. 3879 * This check is not redundant - do not remove. 3880 */ 3881 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3882 } 3883 3884 /* task security operations */ 3885 3886 static int selinux_task_alloc(struct task_struct *task, 3887 unsigned long clone_flags) 3888 { 3889 u32 sid = current_sid(); 3890 3891 return avc_has_perm(&selinux_state, 3892 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3893 } 3894 3895 /* 3896 * prepare a new set of credentials for modification 3897 */ 3898 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3899 gfp_t gfp) 3900 { 3901 const struct task_security_struct *old_tsec = selinux_cred(old); 3902 struct task_security_struct *tsec = selinux_cred(new); 3903 3904 *tsec = *old_tsec; 3905 return 0; 3906 } 3907 3908 /* 3909 * transfer the SELinux data to a blank set of creds 3910 */ 3911 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3912 { 3913 const struct task_security_struct *old_tsec = selinux_cred(old); 3914 struct task_security_struct *tsec = selinux_cred(new); 3915 3916 *tsec = *old_tsec; 3917 } 3918 3919 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 3920 { 3921 *secid = cred_sid(c); 3922 } 3923 3924 /* 3925 * set the security data for a kernel service 3926 * - all the creation contexts are set to unlabelled 3927 */ 3928 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3929 { 3930 struct task_security_struct *tsec = selinux_cred(new); 3931 u32 sid = current_sid(); 3932 int ret; 3933 3934 ret = avc_has_perm(&selinux_state, 3935 sid, secid, 3936 SECCLASS_KERNEL_SERVICE, 3937 KERNEL_SERVICE__USE_AS_OVERRIDE, 3938 NULL); 3939 if (ret == 0) { 3940 tsec->sid = secid; 3941 tsec->create_sid = 0; 3942 tsec->keycreate_sid = 0; 3943 tsec->sockcreate_sid = 0; 3944 } 3945 return ret; 3946 } 3947 3948 /* 3949 * set the file creation context in a security record to the same as the 3950 * objective context of the specified inode 3951 */ 3952 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3953 { 3954 struct inode_security_struct *isec = inode_security(inode); 3955 struct task_security_struct *tsec = selinux_cred(new); 3956 u32 sid = current_sid(); 3957 int ret; 3958 3959 ret = avc_has_perm(&selinux_state, 3960 sid, isec->sid, 3961 SECCLASS_KERNEL_SERVICE, 3962 KERNEL_SERVICE__CREATE_FILES_AS, 3963 NULL); 3964 3965 if (ret == 0) 3966 tsec->create_sid = isec->sid; 3967 return ret; 3968 } 3969 3970 static int selinux_kernel_module_request(char *kmod_name) 3971 { 3972 struct common_audit_data ad; 3973 3974 ad.type = LSM_AUDIT_DATA_KMOD; 3975 ad.u.kmod_name = kmod_name; 3976 3977 return avc_has_perm(&selinux_state, 3978 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 3979 SYSTEM__MODULE_REQUEST, &ad); 3980 } 3981 3982 static int selinux_kernel_module_from_file(struct file *file) 3983 { 3984 struct common_audit_data ad; 3985 struct inode_security_struct *isec; 3986 struct file_security_struct *fsec; 3987 u32 sid = current_sid(); 3988 int rc; 3989 3990 /* init_module */ 3991 if (file == NULL) 3992 return avc_has_perm(&selinux_state, 3993 sid, sid, SECCLASS_SYSTEM, 3994 SYSTEM__MODULE_LOAD, NULL); 3995 3996 /* finit_module */ 3997 3998 ad.type = LSM_AUDIT_DATA_FILE; 3999 ad.u.file = file; 4000 4001 fsec = selinux_file(file); 4002 if (sid != fsec->sid) { 4003 rc = avc_has_perm(&selinux_state, 4004 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4005 if (rc) 4006 return rc; 4007 } 4008 4009 isec = inode_security(file_inode(file)); 4010 return avc_has_perm(&selinux_state, 4011 sid, isec->sid, SECCLASS_SYSTEM, 4012 SYSTEM__MODULE_LOAD, &ad); 4013 } 4014 4015 static int selinux_kernel_read_file(struct file *file, 4016 enum kernel_read_file_id id, 4017 bool contents) 4018 { 4019 int rc = 0; 4020 4021 switch (id) { 4022 case READING_MODULE: 4023 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4024 break; 4025 default: 4026 break; 4027 } 4028 4029 return rc; 4030 } 4031 4032 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4033 { 4034 int rc = 0; 4035 4036 switch (id) { 4037 case LOADING_MODULE: 4038 rc = selinux_kernel_module_from_file(NULL); 4039 break; 4040 default: 4041 break; 4042 } 4043 4044 return rc; 4045 } 4046 4047 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4048 { 4049 return avc_has_perm(&selinux_state, 4050 current_sid(), task_sid(p), SECCLASS_PROCESS, 4051 PROCESS__SETPGID, NULL); 4052 } 4053 4054 static int selinux_task_getpgid(struct task_struct *p) 4055 { 4056 return avc_has_perm(&selinux_state, 4057 current_sid(), task_sid(p), SECCLASS_PROCESS, 4058 PROCESS__GETPGID, NULL); 4059 } 4060 4061 static int selinux_task_getsid(struct task_struct *p) 4062 { 4063 return avc_has_perm(&selinux_state, 4064 current_sid(), task_sid(p), SECCLASS_PROCESS, 4065 PROCESS__GETSESSION, NULL); 4066 } 4067 4068 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 4069 { 4070 *secid = task_sid(p); 4071 } 4072 4073 static int selinux_task_setnice(struct task_struct *p, int nice) 4074 { 4075 return avc_has_perm(&selinux_state, 4076 current_sid(), task_sid(p), SECCLASS_PROCESS, 4077 PROCESS__SETSCHED, NULL); 4078 } 4079 4080 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4081 { 4082 return avc_has_perm(&selinux_state, 4083 current_sid(), task_sid(p), SECCLASS_PROCESS, 4084 PROCESS__SETSCHED, NULL); 4085 } 4086 4087 static int selinux_task_getioprio(struct task_struct *p) 4088 { 4089 return avc_has_perm(&selinux_state, 4090 current_sid(), task_sid(p), SECCLASS_PROCESS, 4091 PROCESS__GETSCHED, NULL); 4092 } 4093 4094 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4095 unsigned int flags) 4096 { 4097 u32 av = 0; 4098 4099 if (!flags) 4100 return 0; 4101 if (flags & LSM_PRLIMIT_WRITE) 4102 av |= PROCESS__SETRLIMIT; 4103 if (flags & LSM_PRLIMIT_READ) 4104 av |= PROCESS__GETRLIMIT; 4105 return avc_has_perm(&selinux_state, 4106 cred_sid(cred), cred_sid(tcred), 4107 SECCLASS_PROCESS, av, NULL); 4108 } 4109 4110 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4111 struct rlimit *new_rlim) 4112 { 4113 struct rlimit *old_rlim = p->signal->rlim + resource; 4114 4115 /* Control the ability to change the hard limit (whether 4116 lowering or raising it), so that the hard limit can 4117 later be used as a safe reset point for the soft limit 4118 upon context transitions. See selinux_bprm_committing_creds. */ 4119 if (old_rlim->rlim_max != new_rlim->rlim_max) 4120 return avc_has_perm(&selinux_state, 4121 current_sid(), task_sid(p), 4122 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4123 4124 return 0; 4125 } 4126 4127 static int selinux_task_setscheduler(struct task_struct *p) 4128 { 4129 return avc_has_perm(&selinux_state, 4130 current_sid(), task_sid(p), SECCLASS_PROCESS, 4131 PROCESS__SETSCHED, NULL); 4132 } 4133 4134 static int selinux_task_getscheduler(struct task_struct *p) 4135 { 4136 return avc_has_perm(&selinux_state, 4137 current_sid(), task_sid(p), SECCLASS_PROCESS, 4138 PROCESS__GETSCHED, NULL); 4139 } 4140 4141 static int selinux_task_movememory(struct task_struct *p) 4142 { 4143 return avc_has_perm(&selinux_state, 4144 current_sid(), task_sid(p), SECCLASS_PROCESS, 4145 PROCESS__SETSCHED, NULL); 4146 } 4147 4148 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4149 int sig, const struct cred *cred) 4150 { 4151 u32 secid; 4152 u32 perm; 4153 4154 if (!sig) 4155 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4156 else 4157 perm = signal_to_av(sig); 4158 if (!cred) 4159 secid = current_sid(); 4160 else 4161 secid = cred_sid(cred); 4162 return avc_has_perm(&selinux_state, 4163 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL); 4164 } 4165 4166 static void selinux_task_to_inode(struct task_struct *p, 4167 struct inode *inode) 4168 { 4169 struct inode_security_struct *isec = selinux_inode(inode); 4170 u32 sid = task_sid(p); 4171 4172 spin_lock(&isec->lock); 4173 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4174 isec->sid = sid; 4175 isec->initialized = LABEL_INITIALIZED; 4176 spin_unlock(&isec->lock); 4177 } 4178 4179 /* Returns error only if unable to parse addresses */ 4180 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4181 struct common_audit_data *ad, u8 *proto) 4182 { 4183 int offset, ihlen, ret = -EINVAL; 4184 struct iphdr _iph, *ih; 4185 4186 offset = skb_network_offset(skb); 4187 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4188 if (ih == NULL) 4189 goto out; 4190 4191 ihlen = ih->ihl * 4; 4192 if (ihlen < sizeof(_iph)) 4193 goto out; 4194 4195 ad->u.net->v4info.saddr = ih->saddr; 4196 ad->u.net->v4info.daddr = ih->daddr; 4197 ret = 0; 4198 4199 if (proto) 4200 *proto = ih->protocol; 4201 4202 switch (ih->protocol) { 4203 case IPPROTO_TCP: { 4204 struct tcphdr _tcph, *th; 4205 4206 if (ntohs(ih->frag_off) & IP_OFFSET) 4207 break; 4208 4209 offset += ihlen; 4210 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4211 if (th == NULL) 4212 break; 4213 4214 ad->u.net->sport = th->source; 4215 ad->u.net->dport = th->dest; 4216 break; 4217 } 4218 4219 case IPPROTO_UDP: { 4220 struct udphdr _udph, *uh; 4221 4222 if (ntohs(ih->frag_off) & IP_OFFSET) 4223 break; 4224 4225 offset += ihlen; 4226 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4227 if (uh == NULL) 4228 break; 4229 4230 ad->u.net->sport = uh->source; 4231 ad->u.net->dport = uh->dest; 4232 break; 4233 } 4234 4235 case IPPROTO_DCCP: { 4236 struct dccp_hdr _dccph, *dh; 4237 4238 if (ntohs(ih->frag_off) & IP_OFFSET) 4239 break; 4240 4241 offset += ihlen; 4242 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4243 if (dh == NULL) 4244 break; 4245 4246 ad->u.net->sport = dh->dccph_sport; 4247 ad->u.net->dport = dh->dccph_dport; 4248 break; 4249 } 4250 4251 #if IS_ENABLED(CONFIG_IP_SCTP) 4252 case IPPROTO_SCTP: { 4253 struct sctphdr _sctph, *sh; 4254 4255 if (ntohs(ih->frag_off) & IP_OFFSET) 4256 break; 4257 4258 offset += ihlen; 4259 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4260 if (sh == NULL) 4261 break; 4262 4263 ad->u.net->sport = sh->source; 4264 ad->u.net->dport = sh->dest; 4265 break; 4266 } 4267 #endif 4268 default: 4269 break; 4270 } 4271 out: 4272 return ret; 4273 } 4274 4275 #if IS_ENABLED(CONFIG_IPV6) 4276 4277 /* Returns error only if unable to parse addresses */ 4278 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4279 struct common_audit_data *ad, u8 *proto) 4280 { 4281 u8 nexthdr; 4282 int ret = -EINVAL, offset; 4283 struct ipv6hdr _ipv6h, *ip6; 4284 __be16 frag_off; 4285 4286 offset = skb_network_offset(skb); 4287 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4288 if (ip6 == NULL) 4289 goto out; 4290 4291 ad->u.net->v6info.saddr = ip6->saddr; 4292 ad->u.net->v6info.daddr = ip6->daddr; 4293 ret = 0; 4294 4295 nexthdr = ip6->nexthdr; 4296 offset += sizeof(_ipv6h); 4297 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4298 if (offset < 0) 4299 goto out; 4300 4301 if (proto) 4302 *proto = nexthdr; 4303 4304 switch (nexthdr) { 4305 case IPPROTO_TCP: { 4306 struct tcphdr _tcph, *th; 4307 4308 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4309 if (th == NULL) 4310 break; 4311 4312 ad->u.net->sport = th->source; 4313 ad->u.net->dport = th->dest; 4314 break; 4315 } 4316 4317 case IPPROTO_UDP: { 4318 struct udphdr _udph, *uh; 4319 4320 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4321 if (uh == NULL) 4322 break; 4323 4324 ad->u.net->sport = uh->source; 4325 ad->u.net->dport = uh->dest; 4326 break; 4327 } 4328 4329 case IPPROTO_DCCP: { 4330 struct dccp_hdr _dccph, *dh; 4331 4332 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4333 if (dh == NULL) 4334 break; 4335 4336 ad->u.net->sport = dh->dccph_sport; 4337 ad->u.net->dport = dh->dccph_dport; 4338 break; 4339 } 4340 4341 #if IS_ENABLED(CONFIG_IP_SCTP) 4342 case IPPROTO_SCTP: { 4343 struct sctphdr _sctph, *sh; 4344 4345 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4346 if (sh == NULL) 4347 break; 4348 4349 ad->u.net->sport = sh->source; 4350 ad->u.net->dport = sh->dest; 4351 break; 4352 } 4353 #endif 4354 /* includes fragments */ 4355 default: 4356 break; 4357 } 4358 out: 4359 return ret; 4360 } 4361 4362 #endif /* IPV6 */ 4363 4364 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4365 char **_addrp, int src, u8 *proto) 4366 { 4367 char *addrp; 4368 int ret; 4369 4370 switch (ad->u.net->family) { 4371 case PF_INET: 4372 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4373 if (ret) 4374 goto parse_error; 4375 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4376 &ad->u.net->v4info.daddr); 4377 goto okay; 4378 4379 #if IS_ENABLED(CONFIG_IPV6) 4380 case PF_INET6: 4381 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4382 if (ret) 4383 goto parse_error; 4384 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4385 &ad->u.net->v6info.daddr); 4386 goto okay; 4387 #endif /* IPV6 */ 4388 default: 4389 addrp = NULL; 4390 goto okay; 4391 } 4392 4393 parse_error: 4394 pr_warn( 4395 "SELinux: failure in selinux_parse_skb()," 4396 " unable to parse packet\n"); 4397 return ret; 4398 4399 okay: 4400 if (_addrp) 4401 *_addrp = addrp; 4402 return 0; 4403 } 4404 4405 /** 4406 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4407 * @skb: the packet 4408 * @family: protocol family 4409 * @sid: the packet's peer label SID 4410 * 4411 * Description: 4412 * Check the various different forms of network peer labeling and determine 4413 * the peer label/SID for the packet; most of the magic actually occurs in 4414 * the security server function security_net_peersid_cmp(). The function 4415 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4416 * or -EACCES if @sid is invalid due to inconsistencies with the different 4417 * peer labels. 4418 * 4419 */ 4420 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4421 { 4422 int err; 4423 u32 xfrm_sid; 4424 u32 nlbl_sid; 4425 u32 nlbl_type; 4426 4427 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4428 if (unlikely(err)) 4429 return -EACCES; 4430 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4431 if (unlikely(err)) 4432 return -EACCES; 4433 4434 err = security_net_peersid_resolve(&selinux_state, nlbl_sid, 4435 nlbl_type, xfrm_sid, sid); 4436 if (unlikely(err)) { 4437 pr_warn( 4438 "SELinux: failure in selinux_skb_peerlbl_sid()," 4439 " unable to determine packet's peer label\n"); 4440 return -EACCES; 4441 } 4442 4443 return 0; 4444 } 4445 4446 /** 4447 * selinux_conn_sid - Determine the child socket label for a connection 4448 * @sk_sid: the parent socket's SID 4449 * @skb_sid: the packet's SID 4450 * @conn_sid: the resulting connection SID 4451 * 4452 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4453 * combined with the MLS information from @skb_sid in order to create 4454 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4455 * of @sk_sid. Returns zero on success, negative values on failure. 4456 * 4457 */ 4458 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4459 { 4460 int err = 0; 4461 4462 if (skb_sid != SECSID_NULL) 4463 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid, 4464 conn_sid); 4465 else 4466 *conn_sid = sk_sid; 4467 4468 return err; 4469 } 4470 4471 /* socket security operations */ 4472 4473 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4474 u16 secclass, u32 *socksid) 4475 { 4476 if (tsec->sockcreate_sid > SECSID_NULL) { 4477 *socksid = tsec->sockcreate_sid; 4478 return 0; 4479 } 4480 4481 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid, 4482 secclass, NULL, socksid); 4483 } 4484 4485 static int sock_has_perm(struct sock *sk, u32 perms) 4486 { 4487 struct sk_security_struct *sksec = sk->sk_security; 4488 struct common_audit_data ad; 4489 struct lsm_network_audit net = {0,}; 4490 4491 if (sksec->sid == SECINITSID_KERNEL) 4492 return 0; 4493 4494 ad.type = LSM_AUDIT_DATA_NET; 4495 ad.u.net = &net; 4496 ad.u.net->sk = sk; 4497 4498 return avc_has_perm(&selinux_state, 4499 current_sid(), sksec->sid, sksec->sclass, perms, 4500 &ad); 4501 } 4502 4503 static int selinux_socket_create(int family, int type, 4504 int protocol, int kern) 4505 { 4506 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4507 u32 newsid; 4508 u16 secclass; 4509 int rc; 4510 4511 if (kern) 4512 return 0; 4513 4514 secclass = socket_type_to_security_class(family, type, protocol); 4515 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4516 if (rc) 4517 return rc; 4518 4519 return avc_has_perm(&selinux_state, 4520 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4521 } 4522 4523 static int selinux_socket_post_create(struct socket *sock, int family, 4524 int type, int protocol, int kern) 4525 { 4526 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4527 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4528 struct sk_security_struct *sksec; 4529 u16 sclass = socket_type_to_security_class(family, type, protocol); 4530 u32 sid = SECINITSID_KERNEL; 4531 int err = 0; 4532 4533 if (!kern) { 4534 err = socket_sockcreate_sid(tsec, sclass, &sid); 4535 if (err) 4536 return err; 4537 } 4538 4539 isec->sclass = sclass; 4540 isec->sid = sid; 4541 isec->initialized = LABEL_INITIALIZED; 4542 4543 if (sock->sk) { 4544 sksec = sock->sk->sk_security; 4545 sksec->sclass = sclass; 4546 sksec->sid = sid; 4547 /* Allows detection of the first association on this socket */ 4548 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4549 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4550 4551 err = selinux_netlbl_socket_post_create(sock->sk, family); 4552 } 4553 4554 return err; 4555 } 4556 4557 static int selinux_socket_socketpair(struct socket *socka, 4558 struct socket *sockb) 4559 { 4560 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4561 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4562 4563 sksec_a->peer_sid = sksec_b->sid; 4564 sksec_b->peer_sid = sksec_a->sid; 4565 4566 return 0; 4567 } 4568 4569 /* Range of port numbers used to automatically bind. 4570 Need to determine whether we should perform a name_bind 4571 permission check between the socket and the port number. */ 4572 4573 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4574 { 4575 struct sock *sk = sock->sk; 4576 struct sk_security_struct *sksec = sk->sk_security; 4577 u16 family; 4578 int err; 4579 4580 err = sock_has_perm(sk, SOCKET__BIND); 4581 if (err) 4582 goto out; 4583 4584 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4585 family = sk->sk_family; 4586 if (family == PF_INET || family == PF_INET6) { 4587 char *addrp; 4588 struct common_audit_data ad; 4589 struct lsm_network_audit net = {0,}; 4590 struct sockaddr_in *addr4 = NULL; 4591 struct sockaddr_in6 *addr6 = NULL; 4592 u16 family_sa; 4593 unsigned short snum; 4594 u32 sid, node_perm; 4595 4596 /* 4597 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4598 * that validates multiple binding addresses. Because of this 4599 * need to check address->sa_family as it is possible to have 4600 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4601 */ 4602 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4603 return -EINVAL; 4604 family_sa = address->sa_family; 4605 switch (family_sa) { 4606 case AF_UNSPEC: 4607 case AF_INET: 4608 if (addrlen < sizeof(struct sockaddr_in)) 4609 return -EINVAL; 4610 addr4 = (struct sockaddr_in *)address; 4611 if (family_sa == AF_UNSPEC) { 4612 /* see __inet_bind(), we only want to allow 4613 * AF_UNSPEC if the address is INADDR_ANY 4614 */ 4615 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4616 goto err_af; 4617 family_sa = AF_INET; 4618 } 4619 snum = ntohs(addr4->sin_port); 4620 addrp = (char *)&addr4->sin_addr.s_addr; 4621 break; 4622 case AF_INET6: 4623 if (addrlen < SIN6_LEN_RFC2133) 4624 return -EINVAL; 4625 addr6 = (struct sockaddr_in6 *)address; 4626 snum = ntohs(addr6->sin6_port); 4627 addrp = (char *)&addr6->sin6_addr.s6_addr; 4628 break; 4629 default: 4630 goto err_af; 4631 } 4632 4633 ad.type = LSM_AUDIT_DATA_NET; 4634 ad.u.net = &net; 4635 ad.u.net->sport = htons(snum); 4636 ad.u.net->family = family_sa; 4637 4638 if (snum) { 4639 int low, high; 4640 4641 inet_get_local_port_range(sock_net(sk), &low, &high); 4642 4643 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4644 snum < low || snum > high) { 4645 err = sel_netport_sid(sk->sk_protocol, 4646 snum, &sid); 4647 if (err) 4648 goto out; 4649 err = avc_has_perm(&selinux_state, 4650 sksec->sid, sid, 4651 sksec->sclass, 4652 SOCKET__NAME_BIND, &ad); 4653 if (err) 4654 goto out; 4655 } 4656 } 4657 4658 switch (sksec->sclass) { 4659 case SECCLASS_TCP_SOCKET: 4660 node_perm = TCP_SOCKET__NODE_BIND; 4661 break; 4662 4663 case SECCLASS_UDP_SOCKET: 4664 node_perm = UDP_SOCKET__NODE_BIND; 4665 break; 4666 4667 case SECCLASS_DCCP_SOCKET: 4668 node_perm = DCCP_SOCKET__NODE_BIND; 4669 break; 4670 4671 case SECCLASS_SCTP_SOCKET: 4672 node_perm = SCTP_SOCKET__NODE_BIND; 4673 break; 4674 4675 default: 4676 node_perm = RAWIP_SOCKET__NODE_BIND; 4677 break; 4678 } 4679 4680 err = sel_netnode_sid(addrp, family_sa, &sid); 4681 if (err) 4682 goto out; 4683 4684 if (family_sa == AF_INET) 4685 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4686 else 4687 ad.u.net->v6info.saddr = addr6->sin6_addr; 4688 4689 err = avc_has_perm(&selinux_state, 4690 sksec->sid, sid, 4691 sksec->sclass, node_perm, &ad); 4692 if (err) 4693 goto out; 4694 } 4695 out: 4696 return err; 4697 err_af: 4698 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4699 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4700 return -EINVAL; 4701 return -EAFNOSUPPORT; 4702 } 4703 4704 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4705 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4706 */ 4707 static int selinux_socket_connect_helper(struct socket *sock, 4708 struct sockaddr *address, int addrlen) 4709 { 4710 struct sock *sk = sock->sk; 4711 struct sk_security_struct *sksec = sk->sk_security; 4712 int err; 4713 4714 err = sock_has_perm(sk, SOCKET__CONNECT); 4715 if (err) 4716 return err; 4717 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4718 return -EINVAL; 4719 4720 /* connect(AF_UNSPEC) has special handling, as it is a documented 4721 * way to disconnect the socket 4722 */ 4723 if (address->sa_family == AF_UNSPEC) 4724 return 0; 4725 4726 /* 4727 * If a TCP, DCCP or SCTP socket, check name_connect permission 4728 * for the port. 4729 */ 4730 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4731 sksec->sclass == SECCLASS_DCCP_SOCKET || 4732 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4733 struct common_audit_data ad; 4734 struct lsm_network_audit net = {0,}; 4735 struct sockaddr_in *addr4 = NULL; 4736 struct sockaddr_in6 *addr6 = NULL; 4737 unsigned short snum; 4738 u32 sid, perm; 4739 4740 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4741 * that validates multiple connect addresses. Because of this 4742 * need to check address->sa_family as it is possible to have 4743 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4744 */ 4745 switch (address->sa_family) { 4746 case AF_INET: 4747 addr4 = (struct sockaddr_in *)address; 4748 if (addrlen < sizeof(struct sockaddr_in)) 4749 return -EINVAL; 4750 snum = ntohs(addr4->sin_port); 4751 break; 4752 case AF_INET6: 4753 addr6 = (struct sockaddr_in6 *)address; 4754 if (addrlen < SIN6_LEN_RFC2133) 4755 return -EINVAL; 4756 snum = ntohs(addr6->sin6_port); 4757 break; 4758 default: 4759 /* Note that SCTP services expect -EINVAL, whereas 4760 * others expect -EAFNOSUPPORT. 4761 */ 4762 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4763 return -EINVAL; 4764 else 4765 return -EAFNOSUPPORT; 4766 } 4767 4768 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4769 if (err) 4770 return err; 4771 4772 switch (sksec->sclass) { 4773 case SECCLASS_TCP_SOCKET: 4774 perm = TCP_SOCKET__NAME_CONNECT; 4775 break; 4776 case SECCLASS_DCCP_SOCKET: 4777 perm = DCCP_SOCKET__NAME_CONNECT; 4778 break; 4779 case SECCLASS_SCTP_SOCKET: 4780 perm = SCTP_SOCKET__NAME_CONNECT; 4781 break; 4782 } 4783 4784 ad.type = LSM_AUDIT_DATA_NET; 4785 ad.u.net = &net; 4786 ad.u.net->dport = htons(snum); 4787 ad.u.net->family = address->sa_family; 4788 err = avc_has_perm(&selinux_state, 4789 sksec->sid, sid, sksec->sclass, perm, &ad); 4790 if (err) 4791 return err; 4792 } 4793 4794 return 0; 4795 } 4796 4797 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4798 static int selinux_socket_connect(struct socket *sock, 4799 struct sockaddr *address, int addrlen) 4800 { 4801 int err; 4802 struct sock *sk = sock->sk; 4803 4804 err = selinux_socket_connect_helper(sock, address, addrlen); 4805 if (err) 4806 return err; 4807 4808 return selinux_netlbl_socket_connect(sk, address); 4809 } 4810 4811 static int selinux_socket_listen(struct socket *sock, int backlog) 4812 { 4813 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4814 } 4815 4816 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4817 { 4818 int err; 4819 struct inode_security_struct *isec; 4820 struct inode_security_struct *newisec; 4821 u16 sclass; 4822 u32 sid; 4823 4824 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4825 if (err) 4826 return err; 4827 4828 isec = inode_security_novalidate(SOCK_INODE(sock)); 4829 spin_lock(&isec->lock); 4830 sclass = isec->sclass; 4831 sid = isec->sid; 4832 spin_unlock(&isec->lock); 4833 4834 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4835 newisec->sclass = sclass; 4836 newisec->sid = sid; 4837 newisec->initialized = LABEL_INITIALIZED; 4838 4839 return 0; 4840 } 4841 4842 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4843 int size) 4844 { 4845 return sock_has_perm(sock->sk, SOCKET__WRITE); 4846 } 4847 4848 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4849 int size, int flags) 4850 { 4851 return sock_has_perm(sock->sk, SOCKET__READ); 4852 } 4853 4854 static int selinux_socket_getsockname(struct socket *sock) 4855 { 4856 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4857 } 4858 4859 static int selinux_socket_getpeername(struct socket *sock) 4860 { 4861 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4862 } 4863 4864 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4865 { 4866 int err; 4867 4868 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4869 if (err) 4870 return err; 4871 4872 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4873 } 4874 4875 static int selinux_socket_getsockopt(struct socket *sock, int level, 4876 int optname) 4877 { 4878 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4879 } 4880 4881 static int selinux_socket_shutdown(struct socket *sock, int how) 4882 { 4883 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4884 } 4885 4886 static int selinux_socket_unix_stream_connect(struct sock *sock, 4887 struct sock *other, 4888 struct sock *newsk) 4889 { 4890 struct sk_security_struct *sksec_sock = sock->sk_security; 4891 struct sk_security_struct *sksec_other = other->sk_security; 4892 struct sk_security_struct *sksec_new = newsk->sk_security; 4893 struct common_audit_data ad; 4894 struct lsm_network_audit net = {0,}; 4895 int err; 4896 4897 ad.type = LSM_AUDIT_DATA_NET; 4898 ad.u.net = &net; 4899 ad.u.net->sk = other; 4900 4901 err = avc_has_perm(&selinux_state, 4902 sksec_sock->sid, sksec_other->sid, 4903 sksec_other->sclass, 4904 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4905 if (err) 4906 return err; 4907 4908 /* server child socket */ 4909 sksec_new->peer_sid = sksec_sock->sid; 4910 err = security_sid_mls_copy(&selinux_state, sksec_other->sid, 4911 sksec_sock->sid, &sksec_new->sid); 4912 if (err) 4913 return err; 4914 4915 /* connecting socket */ 4916 sksec_sock->peer_sid = sksec_new->sid; 4917 4918 return 0; 4919 } 4920 4921 static int selinux_socket_unix_may_send(struct socket *sock, 4922 struct socket *other) 4923 { 4924 struct sk_security_struct *ssec = sock->sk->sk_security; 4925 struct sk_security_struct *osec = other->sk->sk_security; 4926 struct common_audit_data ad; 4927 struct lsm_network_audit net = {0,}; 4928 4929 ad.type = LSM_AUDIT_DATA_NET; 4930 ad.u.net = &net; 4931 ad.u.net->sk = other->sk; 4932 4933 return avc_has_perm(&selinux_state, 4934 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4935 &ad); 4936 } 4937 4938 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4939 char *addrp, u16 family, u32 peer_sid, 4940 struct common_audit_data *ad) 4941 { 4942 int err; 4943 u32 if_sid; 4944 u32 node_sid; 4945 4946 err = sel_netif_sid(ns, ifindex, &if_sid); 4947 if (err) 4948 return err; 4949 err = avc_has_perm(&selinux_state, 4950 peer_sid, if_sid, 4951 SECCLASS_NETIF, NETIF__INGRESS, ad); 4952 if (err) 4953 return err; 4954 4955 err = sel_netnode_sid(addrp, family, &node_sid); 4956 if (err) 4957 return err; 4958 return avc_has_perm(&selinux_state, 4959 peer_sid, node_sid, 4960 SECCLASS_NODE, NODE__RECVFROM, ad); 4961 } 4962 4963 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4964 u16 family) 4965 { 4966 int err = 0; 4967 struct sk_security_struct *sksec = sk->sk_security; 4968 u32 sk_sid = sksec->sid; 4969 struct common_audit_data ad; 4970 struct lsm_network_audit net = {0,}; 4971 char *addrp; 4972 4973 ad.type = LSM_AUDIT_DATA_NET; 4974 ad.u.net = &net; 4975 ad.u.net->netif = skb->skb_iif; 4976 ad.u.net->family = family; 4977 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4978 if (err) 4979 return err; 4980 4981 if (selinux_secmark_enabled()) { 4982 err = avc_has_perm(&selinux_state, 4983 sk_sid, skb->secmark, SECCLASS_PACKET, 4984 PACKET__RECV, &ad); 4985 if (err) 4986 return err; 4987 } 4988 4989 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4990 if (err) 4991 return err; 4992 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4993 4994 return err; 4995 } 4996 4997 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4998 { 4999 int err; 5000 struct sk_security_struct *sksec = sk->sk_security; 5001 u16 family = sk->sk_family; 5002 u32 sk_sid = sksec->sid; 5003 struct common_audit_data ad; 5004 struct lsm_network_audit net = {0,}; 5005 char *addrp; 5006 u8 secmark_active; 5007 u8 peerlbl_active; 5008 5009 if (family != PF_INET && family != PF_INET6) 5010 return 0; 5011 5012 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5013 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5014 family = PF_INET; 5015 5016 /* If any sort of compatibility mode is enabled then handoff processing 5017 * to the selinux_sock_rcv_skb_compat() function to deal with the 5018 * special handling. We do this in an attempt to keep this function 5019 * as fast and as clean as possible. */ 5020 if (!selinux_policycap_netpeer()) 5021 return selinux_sock_rcv_skb_compat(sk, skb, family); 5022 5023 secmark_active = selinux_secmark_enabled(); 5024 peerlbl_active = selinux_peerlbl_enabled(); 5025 if (!secmark_active && !peerlbl_active) 5026 return 0; 5027 5028 ad.type = LSM_AUDIT_DATA_NET; 5029 ad.u.net = &net; 5030 ad.u.net->netif = skb->skb_iif; 5031 ad.u.net->family = family; 5032 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5033 if (err) 5034 return err; 5035 5036 if (peerlbl_active) { 5037 u32 peer_sid; 5038 5039 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5040 if (err) 5041 return err; 5042 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5043 addrp, family, peer_sid, &ad); 5044 if (err) { 5045 selinux_netlbl_err(skb, family, err, 0); 5046 return err; 5047 } 5048 err = avc_has_perm(&selinux_state, 5049 sk_sid, peer_sid, SECCLASS_PEER, 5050 PEER__RECV, &ad); 5051 if (err) { 5052 selinux_netlbl_err(skb, family, err, 0); 5053 return err; 5054 } 5055 } 5056 5057 if (secmark_active) { 5058 err = avc_has_perm(&selinux_state, 5059 sk_sid, skb->secmark, SECCLASS_PACKET, 5060 PACKET__RECV, &ad); 5061 if (err) 5062 return err; 5063 } 5064 5065 return err; 5066 } 5067 5068 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 5069 int __user *optlen, unsigned len) 5070 { 5071 int err = 0; 5072 char *scontext; 5073 u32 scontext_len; 5074 struct sk_security_struct *sksec = sock->sk->sk_security; 5075 u32 peer_sid = SECSID_NULL; 5076 5077 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5078 sksec->sclass == SECCLASS_TCP_SOCKET || 5079 sksec->sclass == SECCLASS_SCTP_SOCKET) 5080 peer_sid = sksec->peer_sid; 5081 if (peer_sid == SECSID_NULL) 5082 return -ENOPROTOOPT; 5083 5084 err = security_sid_to_context(&selinux_state, peer_sid, &scontext, 5085 &scontext_len); 5086 if (err) 5087 return err; 5088 5089 if (scontext_len > len) { 5090 err = -ERANGE; 5091 goto out_len; 5092 } 5093 5094 if (copy_to_user(optval, scontext, scontext_len)) 5095 err = -EFAULT; 5096 5097 out_len: 5098 if (put_user(scontext_len, optlen)) 5099 err = -EFAULT; 5100 kfree(scontext); 5101 return err; 5102 } 5103 5104 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5105 { 5106 u32 peer_secid = SECSID_NULL; 5107 u16 family; 5108 struct inode_security_struct *isec; 5109 5110 if (skb && skb->protocol == htons(ETH_P_IP)) 5111 family = PF_INET; 5112 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5113 family = PF_INET6; 5114 else if (sock) 5115 family = sock->sk->sk_family; 5116 else 5117 goto out; 5118 5119 if (sock && family == PF_UNIX) { 5120 isec = inode_security_novalidate(SOCK_INODE(sock)); 5121 peer_secid = isec->sid; 5122 } else if (skb) 5123 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5124 5125 out: 5126 *secid = peer_secid; 5127 if (peer_secid == SECSID_NULL) 5128 return -EINVAL; 5129 return 0; 5130 } 5131 5132 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5133 { 5134 struct sk_security_struct *sksec; 5135 5136 sksec = kzalloc(sizeof(*sksec), priority); 5137 if (!sksec) 5138 return -ENOMEM; 5139 5140 sksec->peer_sid = SECINITSID_UNLABELED; 5141 sksec->sid = SECINITSID_UNLABELED; 5142 sksec->sclass = SECCLASS_SOCKET; 5143 selinux_netlbl_sk_security_reset(sksec); 5144 sk->sk_security = sksec; 5145 5146 return 0; 5147 } 5148 5149 static void selinux_sk_free_security(struct sock *sk) 5150 { 5151 struct sk_security_struct *sksec = sk->sk_security; 5152 5153 sk->sk_security = NULL; 5154 selinux_netlbl_sk_security_free(sksec); 5155 kfree(sksec); 5156 } 5157 5158 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5159 { 5160 struct sk_security_struct *sksec = sk->sk_security; 5161 struct sk_security_struct *newsksec = newsk->sk_security; 5162 5163 newsksec->sid = sksec->sid; 5164 newsksec->peer_sid = sksec->peer_sid; 5165 newsksec->sclass = sksec->sclass; 5166 5167 selinux_netlbl_sk_security_reset(newsksec); 5168 } 5169 5170 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 5171 { 5172 if (!sk) 5173 *secid = SECINITSID_ANY_SOCKET; 5174 else { 5175 struct sk_security_struct *sksec = sk->sk_security; 5176 5177 *secid = sksec->sid; 5178 } 5179 } 5180 5181 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5182 { 5183 struct inode_security_struct *isec = 5184 inode_security_novalidate(SOCK_INODE(parent)); 5185 struct sk_security_struct *sksec = sk->sk_security; 5186 5187 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5188 sk->sk_family == PF_UNIX) 5189 isec->sid = sksec->sid; 5190 sksec->sclass = isec->sclass; 5191 } 5192 5193 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming 5194 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association 5195 * already present). 5196 */ 5197 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep, 5198 struct sk_buff *skb) 5199 { 5200 struct sk_security_struct *sksec = ep->base.sk->sk_security; 5201 struct common_audit_data ad; 5202 struct lsm_network_audit net = {0,}; 5203 u8 peerlbl_active; 5204 u32 peer_sid = SECINITSID_UNLABELED; 5205 u32 conn_sid; 5206 int err = 0; 5207 5208 if (!selinux_policycap_extsockclass()) 5209 return 0; 5210 5211 peerlbl_active = selinux_peerlbl_enabled(); 5212 5213 if (peerlbl_active) { 5214 /* This will return peer_sid = SECSID_NULL if there are 5215 * no peer labels, see security_net_peersid_resolve(). 5216 */ 5217 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family, 5218 &peer_sid); 5219 if (err) 5220 return err; 5221 5222 if (peer_sid == SECSID_NULL) 5223 peer_sid = SECINITSID_UNLABELED; 5224 } 5225 5226 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5227 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5228 5229 /* Here as first association on socket. As the peer SID 5230 * was allowed by peer recv (and the netif/node checks), 5231 * then it is approved by policy and used as the primary 5232 * peer SID for getpeercon(3). 5233 */ 5234 sksec->peer_sid = peer_sid; 5235 } else if (sksec->peer_sid != peer_sid) { 5236 /* Other association peer SIDs are checked to enforce 5237 * consistency among the peer SIDs. 5238 */ 5239 ad.type = LSM_AUDIT_DATA_NET; 5240 ad.u.net = &net; 5241 ad.u.net->sk = ep->base.sk; 5242 err = avc_has_perm(&selinux_state, 5243 sksec->peer_sid, peer_sid, sksec->sclass, 5244 SCTP_SOCKET__ASSOCIATION, &ad); 5245 if (err) 5246 return err; 5247 } 5248 5249 /* Compute the MLS component for the connection and store 5250 * the information in ep. This will be used by SCTP TCP type 5251 * sockets and peeled off connections as they cause a new 5252 * socket to be generated. selinux_sctp_sk_clone() will then 5253 * plug this into the new socket. 5254 */ 5255 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid); 5256 if (err) 5257 return err; 5258 5259 ep->secid = conn_sid; 5260 ep->peer_secid = peer_sid; 5261 5262 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5263 return selinux_netlbl_sctp_assoc_request(ep, skb); 5264 } 5265 5266 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5267 * based on their @optname. 5268 */ 5269 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5270 struct sockaddr *address, 5271 int addrlen) 5272 { 5273 int len, err = 0, walk_size = 0; 5274 void *addr_buf; 5275 struct sockaddr *addr; 5276 struct socket *sock; 5277 5278 if (!selinux_policycap_extsockclass()) 5279 return 0; 5280 5281 /* Process one or more addresses that may be IPv4 or IPv6 */ 5282 sock = sk->sk_socket; 5283 addr_buf = address; 5284 5285 while (walk_size < addrlen) { 5286 if (walk_size + sizeof(sa_family_t) > addrlen) 5287 return -EINVAL; 5288 5289 addr = addr_buf; 5290 switch (addr->sa_family) { 5291 case AF_UNSPEC: 5292 case AF_INET: 5293 len = sizeof(struct sockaddr_in); 5294 break; 5295 case AF_INET6: 5296 len = sizeof(struct sockaddr_in6); 5297 break; 5298 default: 5299 return -EINVAL; 5300 } 5301 5302 if (walk_size + len > addrlen) 5303 return -EINVAL; 5304 5305 err = -EINVAL; 5306 switch (optname) { 5307 /* Bind checks */ 5308 case SCTP_PRIMARY_ADDR: 5309 case SCTP_SET_PEER_PRIMARY_ADDR: 5310 case SCTP_SOCKOPT_BINDX_ADD: 5311 err = selinux_socket_bind(sock, addr, len); 5312 break; 5313 /* Connect checks */ 5314 case SCTP_SOCKOPT_CONNECTX: 5315 case SCTP_PARAM_SET_PRIMARY: 5316 case SCTP_PARAM_ADD_IP: 5317 case SCTP_SENDMSG_CONNECT: 5318 err = selinux_socket_connect_helper(sock, addr, len); 5319 if (err) 5320 return err; 5321 5322 /* As selinux_sctp_bind_connect() is called by the 5323 * SCTP protocol layer, the socket is already locked, 5324 * therefore selinux_netlbl_socket_connect_locked() 5325 * is called here. The situations handled are: 5326 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5327 * whenever a new IP address is added or when a new 5328 * primary address is selected. 5329 * Note that an SCTP connect(2) call happens before 5330 * the SCTP protocol layer and is handled via 5331 * selinux_socket_connect(). 5332 */ 5333 err = selinux_netlbl_socket_connect_locked(sk, addr); 5334 break; 5335 } 5336 5337 if (err) 5338 return err; 5339 5340 addr_buf += len; 5341 walk_size += len; 5342 } 5343 5344 return 0; 5345 } 5346 5347 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5348 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk, 5349 struct sock *newsk) 5350 { 5351 struct sk_security_struct *sksec = sk->sk_security; 5352 struct sk_security_struct *newsksec = newsk->sk_security; 5353 5354 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5355 * the non-sctp clone version. 5356 */ 5357 if (!selinux_policycap_extsockclass()) 5358 return selinux_sk_clone_security(sk, newsk); 5359 5360 newsksec->sid = ep->secid; 5361 newsksec->peer_sid = ep->peer_secid; 5362 newsksec->sclass = sksec->sclass; 5363 selinux_netlbl_sctp_sk_clone(sk, newsk); 5364 } 5365 5366 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5367 struct request_sock *req) 5368 { 5369 struct sk_security_struct *sksec = sk->sk_security; 5370 int err; 5371 u16 family = req->rsk_ops->family; 5372 u32 connsid; 5373 u32 peersid; 5374 5375 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5376 if (err) 5377 return err; 5378 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5379 if (err) 5380 return err; 5381 req->secid = connsid; 5382 req->peer_secid = peersid; 5383 5384 return selinux_netlbl_inet_conn_request(req, family); 5385 } 5386 5387 static void selinux_inet_csk_clone(struct sock *newsk, 5388 const struct request_sock *req) 5389 { 5390 struct sk_security_struct *newsksec = newsk->sk_security; 5391 5392 newsksec->sid = req->secid; 5393 newsksec->peer_sid = req->peer_secid; 5394 /* NOTE: Ideally, we should also get the isec->sid for the 5395 new socket in sync, but we don't have the isec available yet. 5396 So we will wait until sock_graft to do it, by which 5397 time it will have been created and available. */ 5398 5399 /* We don't need to take any sort of lock here as we are the only 5400 * thread with access to newsksec */ 5401 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5402 } 5403 5404 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5405 { 5406 u16 family = sk->sk_family; 5407 struct sk_security_struct *sksec = sk->sk_security; 5408 5409 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5410 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5411 family = PF_INET; 5412 5413 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5414 } 5415 5416 static int selinux_secmark_relabel_packet(u32 sid) 5417 { 5418 const struct task_security_struct *__tsec; 5419 u32 tsid; 5420 5421 __tsec = selinux_cred(current_cred()); 5422 tsid = __tsec->sid; 5423 5424 return avc_has_perm(&selinux_state, 5425 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5426 NULL); 5427 } 5428 5429 static void selinux_secmark_refcount_inc(void) 5430 { 5431 atomic_inc(&selinux_secmark_refcount); 5432 } 5433 5434 static void selinux_secmark_refcount_dec(void) 5435 { 5436 atomic_dec(&selinux_secmark_refcount); 5437 } 5438 5439 static void selinux_req_classify_flow(const struct request_sock *req, 5440 struct flowi_common *flic) 5441 { 5442 flic->flowic_secid = req->secid; 5443 } 5444 5445 static int selinux_tun_dev_alloc_security(void **security) 5446 { 5447 struct tun_security_struct *tunsec; 5448 5449 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5450 if (!tunsec) 5451 return -ENOMEM; 5452 tunsec->sid = current_sid(); 5453 5454 *security = tunsec; 5455 return 0; 5456 } 5457 5458 static void selinux_tun_dev_free_security(void *security) 5459 { 5460 kfree(security); 5461 } 5462 5463 static int selinux_tun_dev_create(void) 5464 { 5465 u32 sid = current_sid(); 5466 5467 /* we aren't taking into account the "sockcreate" SID since the socket 5468 * that is being created here is not a socket in the traditional sense, 5469 * instead it is a private sock, accessible only to the kernel, and 5470 * representing a wide range of network traffic spanning multiple 5471 * connections unlike traditional sockets - check the TUN driver to 5472 * get a better understanding of why this socket is special */ 5473 5474 return avc_has_perm(&selinux_state, 5475 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5476 NULL); 5477 } 5478 5479 static int selinux_tun_dev_attach_queue(void *security) 5480 { 5481 struct tun_security_struct *tunsec = security; 5482 5483 return avc_has_perm(&selinux_state, 5484 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5485 TUN_SOCKET__ATTACH_QUEUE, NULL); 5486 } 5487 5488 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5489 { 5490 struct tun_security_struct *tunsec = security; 5491 struct sk_security_struct *sksec = sk->sk_security; 5492 5493 /* we don't currently perform any NetLabel based labeling here and it 5494 * isn't clear that we would want to do so anyway; while we could apply 5495 * labeling without the support of the TUN user the resulting labeled 5496 * traffic from the other end of the connection would almost certainly 5497 * cause confusion to the TUN user that had no idea network labeling 5498 * protocols were being used */ 5499 5500 sksec->sid = tunsec->sid; 5501 sksec->sclass = SECCLASS_TUN_SOCKET; 5502 5503 return 0; 5504 } 5505 5506 static int selinux_tun_dev_open(void *security) 5507 { 5508 struct tun_security_struct *tunsec = security; 5509 u32 sid = current_sid(); 5510 int err; 5511 5512 err = avc_has_perm(&selinux_state, 5513 sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5514 TUN_SOCKET__RELABELFROM, NULL); 5515 if (err) 5516 return err; 5517 err = avc_has_perm(&selinux_state, 5518 sid, sid, SECCLASS_TUN_SOCKET, 5519 TUN_SOCKET__RELABELTO, NULL); 5520 if (err) 5521 return err; 5522 tunsec->sid = sid; 5523 5524 return 0; 5525 } 5526 5527 #ifdef CONFIG_NETFILTER 5528 5529 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5530 const struct net_device *indev, 5531 u16 family) 5532 { 5533 int err; 5534 char *addrp; 5535 u32 peer_sid; 5536 struct common_audit_data ad; 5537 struct lsm_network_audit net = {0,}; 5538 u8 secmark_active; 5539 u8 netlbl_active; 5540 u8 peerlbl_active; 5541 5542 if (!selinux_policycap_netpeer()) 5543 return NF_ACCEPT; 5544 5545 secmark_active = selinux_secmark_enabled(); 5546 netlbl_active = netlbl_enabled(); 5547 peerlbl_active = selinux_peerlbl_enabled(); 5548 if (!secmark_active && !peerlbl_active) 5549 return NF_ACCEPT; 5550 5551 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5552 return NF_DROP; 5553 5554 ad.type = LSM_AUDIT_DATA_NET; 5555 ad.u.net = &net; 5556 ad.u.net->netif = indev->ifindex; 5557 ad.u.net->family = family; 5558 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5559 return NF_DROP; 5560 5561 if (peerlbl_active) { 5562 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5563 addrp, family, peer_sid, &ad); 5564 if (err) { 5565 selinux_netlbl_err(skb, family, err, 1); 5566 return NF_DROP; 5567 } 5568 } 5569 5570 if (secmark_active) 5571 if (avc_has_perm(&selinux_state, 5572 peer_sid, skb->secmark, 5573 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5574 return NF_DROP; 5575 5576 if (netlbl_active) 5577 /* we do this in the FORWARD path and not the POST_ROUTING 5578 * path because we want to make sure we apply the necessary 5579 * labeling before IPsec is applied so we can leverage AH 5580 * protection */ 5581 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5582 return NF_DROP; 5583 5584 return NF_ACCEPT; 5585 } 5586 5587 static unsigned int selinux_ipv4_forward(void *priv, 5588 struct sk_buff *skb, 5589 const struct nf_hook_state *state) 5590 { 5591 return selinux_ip_forward(skb, state->in, PF_INET); 5592 } 5593 5594 #if IS_ENABLED(CONFIG_IPV6) 5595 static unsigned int selinux_ipv6_forward(void *priv, 5596 struct sk_buff *skb, 5597 const struct nf_hook_state *state) 5598 { 5599 return selinux_ip_forward(skb, state->in, PF_INET6); 5600 } 5601 #endif /* IPV6 */ 5602 5603 static unsigned int selinux_ip_output(struct sk_buff *skb, 5604 u16 family) 5605 { 5606 struct sock *sk; 5607 u32 sid; 5608 5609 if (!netlbl_enabled()) 5610 return NF_ACCEPT; 5611 5612 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5613 * because we want to make sure we apply the necessary labeling 5614 * before IPsec is applied so we can leverage AH protection */ 5615 sk = skb->sk; 5616 if (sk) { 5617 struct sk_security_struct *sksec; 5618 5619 if (sk_listener(sk)) 5620 /* if the socket is the listening state then this 5621 * packet is a SYN-ACK packet which means it needs to 5622 * be labeled based on the connection/request_sock and 5623 * not the parent socket. unfortunately, we can't 5624 * lookup the request_sock yet as it isn't queued on 5625 * the parent socket until after the SYN-ACK is sent. 5626 * the "solution" is to simply pass the packet as-is 5627 * as any IP option based labeling should be copied 5628 * from the initial connection request (in the IP 5629 * layer). it is far from ideal, but until we get a 5630 * security label in the packet itself this is the 5631 * best we can do. */ 5632 return NF_ACCEPT; 5633 5634 /* standard practice, label using the parent socket */ 5635 sksec = sk->sk_security; 5636 sid = sksec->sid; 5637 } else 5638 sid = SECINITSID_KERNEL; 5639 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5640 return NF_DROP; 5641 5642 return NF_ACCEPT; 5643 } 5644 5645 static unsigned int selinux_ipv4_output(void *priv, 5646 struct sk_buff *skb, 5647 const struct nf_hook_state *state) 5648 { 5649 return selinux_ip_output(skb, PF_INET); 5650 } 5651 5652 #if IS_ENABLED(CONFIG_IPV6) 5653 static unsigned int selinux_ipv6_output(void *priv, 5654 struct sk_buff *skb, 5655 const struct nf_hook_state *state) 5656 { 5657 return selinux_ip_output(skb, PF_INET6); 5658 } 5659 #endif /* IPV6 */ 5660 5661 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5662 int ifindex, 5663 u16 family) 5664 { 5665 struct sock *sk = skb_to_full_sk(skb); 5666 struct sk_security_struct *sksec; 5667 struct common_audit_data ad; 5668 struct lsm_network_audit net = {0,}; 5669 char *addrp; 5670 u8 proto; 5671 5672 if (sk == NULL) 5673 return NF_ACCEPT; 5674 sksec = sk->sk_security; 5675 5676 ad.type = LSM_AUDIT_DATA_NET; 5677 ad.u.net = &net; 5678 ad.u.net->netif = ifindex; 5679 ad.u.net->family = family; 5680 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5681 return NF_DROP; 5682 5683 if (selinux_secmark_enabled()) 5684 if (avc_has_perm(&selinux_state, 5685 sksec->sid, skb->secmark, 5686 SECCLASS_PACKET, PACKET__SEND, &ad)) 5687 return NF_DROP_ERR(-ECONNREFUSED); 5688 5689 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5690 return NF_DROP_ERR(-ECONNREFUSED); 5691 5692 return NF_ACCEPT; 5693 } 5694 5695 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5696 const struct net_device *outdev, 5697 u16 family) 5698 { 5699 u32 secmark_perm; 5700 u32 peer_sid; 5701 int ifindex = outdev->ifindex; 5702 struct sock *sk; 5703 struct common_audit_data ad; 5704 struct lsm_network_audit net = {0,}; 5705 char *addrp; 5706 u8 secmark_active; 5707 u8 peerlbl_active; 5708 5709 /* If any sort of compatibility mode is enabled then handoff processing 5710 * to the selinux_ip_postroute_compat() function to deal with the 5711 * special handling. We do this in an attempt to keep this function 5712 * as fast and as clean as possible. */ 5713 if (!selinux_policycap_netpeer()) 5714 return selinux_ip_postroute_compat(skb, ifindex, family); 5715 5716 secmark_active = selinux_secmark_enabled(); 5717 peerlbl_active = selinux_peerlbl_enabled(); 5718 if (!secmark_active && !peerlbl_active) 5719 return NF_ACCEPT; 5720 5721 sk = skb_to_full_sk(skb); 5722 5723 #ifdef CONFIG_XFRM 5724 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5725 * packet transformation so allow the packet to pass without any checks 5726 * since we'll have another chance to perform access control checks 5727 * when the packet is on it's final way out. 5728 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5729 * is NULL, in this case go ahead and apply access control. 5730 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5731 * TCP listening state we cannot wait until the XFRM processing 5732 * is done as we will miss out on the SA label if we do; 5733 * unfortunately, this means more work, but it is only once per 5734 * connection. */ 5735 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5736 !(sk && sk_listener(sk))) 5737 return NF_ACCEPT; 5738 #endif 5739 5740 if (sk == NULL) { 5741 /* Without an associated socket the packet is either coming 5742 * from the kernel or it is being forwarded; check the packet 5743 * to determine which and if the packet is being forwarded 5744 * query the packet directly to determine the security label. */ 5745 if (skb->skb_iif) { 5746 secmark_perm = PACKET__FORWARD_OUT; 5747 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5748 return NF_DROP; 5749 } else { 5750 secmark_perm = PACKET__SEND; 5751 peer_sid = SECINITSID_KERNEL; 5752 } 5753 } else if (sk_listener(sk)) { 5754 /* Locally generated packet but the associated socket is in the 5755 * listening state which means this is a SYN-ACK packet. In 5756 * this particular case the correct security label is assigned 5757 * to the connection/request_sock but unfortunately we can't 5758 * query the request_sock as it isn't queued on the parent 5759 * socket until after the SYN-ACK packet is sent; the only 5760 * viable choice is to regenerate the label like we do in 5761 * selinux_inet_conn_request(). See also selinux_ip_output() 5762 * for similar problems. */ 5763 u32 skb_sid; 5764 struct sk_security_struct *sksec; 5765 5766 sksec = sk->sk_security; 5767 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5768 return NF_DROP; 5769 /* At this point, if the returned skb peerlbl is SECSID_NULL 5770 * and the packet has been through at least one XFRM 5771 * transformation then we must be dealing with the "final" 5772 * form of labeled IPsec packet; since we've already applied 5773 * all of our access controls on this packet we can safely 5774 * pass the packet. */ 5775 if (skb_sid == SECSID_NULL) { 5776 switch (family) { 5777 case PF_INET: 5778 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5779 return NF_ACCEPT; 5780 break; 5781 case PF_INET6: 5782 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5783 return NF_ACCEPT; 5784 break; 5785 default: 5786 return NF_DROP_ERR(-ECONNREFUSED); 5787 } 5788 } 5789 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5790 return NF_DROP; 5791 secmark_perm = PACKET__SEND; 5792 } else { 5793 /* Locally generated packet, fetch the security label from the 5794 * associated socket. */ 5795 struct sk_security_struct *sksec = sk->sk_security; 5796 peer_sid = sksec->sid; 5797 secmark_perm = PACKET__SEND; 5798 } 5799 5800 ad.type = LSM_AUDIT_DATA_NET; 5801 ad.u.net = &net; 5802 ad.u.net->netif = ifindex; 5803 ad.u.net->family = family; 5804 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5805 return NF_DROP; 5806 5807 if (secmark_active) 5808 if (avc_has_perm(&selinux_state, 5809 peer_sid, skb->secmark, 5810 SECCLASS_PACKET, secmark_perm, &ad)) 5811 return NF_DROP_ERR(-ECONNREFUSED); 5812 5813 if (peerlbl_active) { 5814 u32 if_sid; 5815 u32 node_sid; 5816 5817 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5818 return NF_DROP; 5819 if (avc_has_perm(&selinux_state, 5820 peer_sid, if_sid, 5821 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5822 return NF_DROP_ERR(-ECONNREFUSED); 5823 5824 if (sel_netnode_sid(addrp, family, &node_sid)) 5825 return NF_DROP; 5826 if (avc_has_perm(&selinux_state, 5827 peer_sid, node_sid, 5828 SECCLASS_NODE, NODE__SENDTO, &ad)) 5829 return NF_DROP_ERR(-ECONNREFUSED); 5830 } 5831 5832 return NF_ACCEPT; 5833 } 5834 5835 static unsigned int selinux_ipv4_postroute(void *priv, 5836 struct sk_buff *skb, 5837 const struct nf_hook_state *state) 5838 { 5839 return selinux_ip_postroute(skb, state->out, PF_INET); 5840 } 5841 5842 #if IS_ENABLED(CONFIG_IPV6) 5843 static unsigned int selinux_ipv6_postroute(void *priv, 5844 struct sk_buff *skb, 5845 const struct nf_hook_state *state) 5846 { 5847 return selinux_ip_postroute(skb, state->out, PF_INET6); 5848 } 5849 #endif /* IPV6 */ 5850 5851 #endif /* CONFIG_NETFILTER */ 5852 5853 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5854 { 5855 int rc = 0; 5856 unsigned int msg_len; 5857 unsigned int data_len = skb->len; 5858 unsigned char *data = skb->data; 5859 struct nlmsghdr *nlh; 5860 struct sk_security_struct *sksec = sk->sk_security; 5861 u16 sclass = sksec->sclass; 5862 u32 perm; 5863 5864 while (data_len >= nlmsg_total_size(0)) { 5865 nlh = (struct nlmsghdr *)data; 5866 5867 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5868 * users which means we can't reject skb's with bogus 5869 * length fields; our solution is to follow what 5870 * netlink_rcv_skb() does and simply skip processing at 5871 * messages with length fields that are clearly junk 5872 */ 5873 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5874 return 0; 5875 5876 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5877 if (rc == 0) { 5878 rc = sock_has_perm(sk, perm); 5879 if (rc) 5880 return rc; 5881 } else if (rc == -EINVAL) { 5882 /* -EINVAL is a missing msg/perm mapping */ 5883 pr_warn_ratelimited("SELinux: unrecognized netlink" 5884 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5885 " pid=%d comm=%s\n", 5886 sk->sk_protocol, nlh->nlmsg_type, 5887 secclass_map[sclass - 1].name, 5888 task_pid_nr(current), current->comm); 5889 if (enforcing_enabled(&selinux_state) && 5890 !security_get_allow_unknown(&selinux_state)) 5891 return rc; 5892 rc = 0; 5893 } else if (rc == -ENOENT) { 5894 /* -ENOENT is a missing socket/class mapping, ignore */ 5895 rc = 0; 5896 } else { 5897 return rc; 5898 } 5899 5900 /* move to the next message after applying netlink padding */ 5901 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5902 if (msg_len >= data_len) 5903 return 0; 5904 data_len -= msg_len; 5905 data += msg_len; 5906 } 5907 5908 return rc; 5909 } 5910 5911 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5912 { 5913 isec->sclass = sclass; 5914 isec->sid = current_sid(); 5915 } 5916 5917 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5918 u32 perms) 5919 { 5920 struct ipc_security_struct *isec; 5921 struct common_audit_data ad; 5922 u32 sid = current_sid(); 5923 5924 isec = selinux_ipc(ipc_perms); 5925 5926 ad.type = LSM_AUDIT_DATA_IPC; 5927 ad.u.ipc_id = ipc_perms->key; 5928 5929 return avc_has_perm(&selinux_state, 5930 sid, isec->sid, isec->sclass, perms, &ad); 5931 } 5932 5933 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5934 { 5935 struct msg_security_struct *msec; 5936 5937 msec = selinux_msg_msg(msg); 5938 msec->sid = SECINITSID_UNLABELED; 5939 5940 return 0; 5941 } 5942 5943 /* message queue security operations */ 5944 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5945 { 5946 struct ipc_security_struct *isec; 5947 struct common_audit_data ad; 5948 u32 sid = current_sid(); 5949 int rc; 5950 5951 isec = selinux_ipc(msq); 5952 ipc_init_security(isec, SECCLASS_MSGQ); 5953 5954 ad.type = LSM_AUDIT_DATA_IPC; 5955 ad.u.ipc_id = msq->key; 5956 5957 rc = avc_has_perm(&selinux_state, 5958 sid, isec->sid, SECCLASS_MSGQ, 5959 MSGQ__CREATE, &ad); 5960 return rc; 5961 } 5962 5963 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 5964 { 5965 struct ipc_security_struct *isec; 5966 struct common_audit_data ad; 5967 u32 sid = current_sid(); 5968 5969 isec = selinux_ipc(msq); 5970 5971 ad.type = LSM_AUDIT_DATA_IPC; 5972 ad.u.ipc_id = msq->key; 5973 5974 return avc_has_perm(&selinux_state, 5975 sid, isec->sid, SECCLASS_MSGQ, 5976 MSGQ__ASSOCIATE, &ad); 5977 } 5978 5979 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 5980 { 5981 int err; 5982 int perms; 5983 5984 switch (cmd) { 5985 case IPC_INFO: 5986 case MSG_INFO: 5987 /* No specific object, just general system-wide information. */ 5988 return avc_has_perm(&selinux_state, 5989 current_sid(), SECINITSID_KERNEL, 5990 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 5991 case IPC_STAT: 5992 case MSG_STAT: 5993 case MSG_STAT_ANY: 5994 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 5995 break; 5996 case IPC_SET: 5997 perms = MSGQ__SETATTR; 5998 break; 5999 case IPC_RMID: 6000 perms = MSGQ__DESTROY; 6001 break; 6002 default: 6003 return 0; 6004 } 6005 6006 err = ipc_has_perm(msq, perms); 6007 return err; 6008 } 6009 6010 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6011 { 6012 struct ipc_security_struct *isec; 6013 struct msg_security_struct *msec; 6014 struct common_audit_data ad; 6015 u32 sid = current_sid(); 6016 int rc; 6017 6018 isec = selinux_ipc(msq); 6019 msec = selinux_msg_msg(msg); 6020 6021 /* 6022 * First time through, need to assign label to the message 6023 */ 6024 if (msec->sid == SECINITSID_UNLABELED) { 6025 /* 6026 * Compute new sid based on current process and 6027 * message queue this message will be stored in 6028 */ 6029 rc = security_transition_sid(&selinux_state, sid, isec->sid, 6030 SECCLASS_MSG, NULL, &msec->sid); 6031 if (rc) 6032 return rc; 6033 } 6034 6035 ad.type = LSM_AUDIT_DATA_IPC; 6036 ad.u.ipc_id = msq->key; 6037 6038 /* Can this process write to the queue? */ 6039 rc = avc_has_perm(&selinux_state, 6040 sid, isec->sid, SECCLASS_MSGQ, 6041 MSGQ__WRITE, &ad); 6042 if (!rc) 6043 /* Can this process send the message */ 6044 rc = avc_has_perm(&selinux_state, 6045 sid, msec->sid, SECCLASS_MSG, 6046 MSG__SEND, &ad); 6047 if (!rc) 6048 /* Can the message be put in the queue? */ 6049 rc = avc_has_perm(&selinux_state, 6050 msec->sid, isec->sid, SECCLASS_MSGQ, 6051 MSGQ__ENQUEUE, &ad); 6052 6053 return rc; 6054 } 6055 6056 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6057 struct task_struct *target, 6058 long type, int mode) 6059 { 6060 struct ipc_security_struct *isec; 6061 struct msg_security_struct *msec; 6062 struct common_audit_data ad; 6063 u32 sid = task_sid(target); 6064 int rc; 6065 6066 isec = selinux_ipc(msq); 6067 msec = selinux_msg_msg(msg); 6068 6069 ad.type = LSM_AUDIT_DATA_IPC; 6070 ad.u.ipc_id = msq->key; 6071 6072 rc = avc_has_perm(&selinux_state, 6073 sid, isec->sid, 6074 SECCLASS_MSGQ, MSGQ__READ, &ad); 6075 if (!rc) 6076 rc = avc_has_perm(&selinux_state, 6077 sid, msec->sid, 6078 SECCLASS_MSG, MSG__RECEIVE, &ad); 6079 return rc; 6080 } 6081 6082 /* Shared Memory security operations */ 6083 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6084 { 6085 struct ipc_security_struct *isec; 6086 struct common_audit_data ad; 6087 u32 sid = current_sid(); 6088 int rc; 6089 6090 isec = selinux_ipc(shp); 6091 ipc_init_security(isec, SECCLASS_SHM); 6092 6093 ad.type = LSM_AUDIT_DATA_IPC; 6094 ad.u.ipc_id = shp->key; 6095 6096 rc = avc_has_perm(&selinux_state, 6097 sid, isec->sid, SECCLASS_SHM, 6098 SHM__CREATE, &ad); 6099 return rc; 6100 } 6101 6102 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6103 { 6104 struct ipc_security_struct *isec; 6105 struct common_audit_data ad; 6106 u32 sid = current_sid(); 6107 6108 isec = selinux_ipc(shp); 6109 6110 ad.type = LSM_AUDIT_DATA_IPC; 6111 ad.u.ipc_id = shp->key; 6112 6113 return avc_has_perm(&selinux_state, 6114 sid, isec->sid, SECCLASS_SHM, 6115 SHM__ASSOCIATE, &ad); 6116 } 6117 6118 /* Note, at this point, shp is locked down */ 6119 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6120 { 6121 int perms; 6122 int err; 6123 6124 switch (cmd) { 6125 case IPC_INFO: 6126 case SHM_INFO: 6127 /* No specific object, just general system-wide information. */ 6128 return avc_has_perm(&selinux_state, 6129 current_sid(), SECINITSID_KERNEL, 6130 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6131 case IPC_STAT: 6132 case SHM_STAT: 6133 case SHM_STAT_ANY: 6134 perms = SHM__GETATTR | SHM__ASSOCIATE; 6135 break; 6136 case IPC_SET: 6137 perms = SHM__SETATTR; 6138 break; 6139 case SHM_LOCK: 6140 case SHM_UNLOCK: 6141 perms = SHM__LOCK; 6142 break; 6143 case IPC_RMID: 6144 perms = SHM__DESTROY; 6145 break; 6146 default: 6147 return 0; 6148 } 6149 6150 err = ipc_has_perm(shp, perms); 6151 return err; 6152 } 6153 6154 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6155 char __user *shmaddr, int shmflg) 6156 { 6157 u32 perms; 6158 6159 if (shmflg & SHM_RDONLY) 6160 perms = SHM__READ; 6161 else 6162 perms = SHM__READ | SHM__WRITE; 6163 6164 return ipc_has_perm(shp, perms); 6165 } 6166 6167 /* Semaphore security operations */ 6168 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6169 { 6170 struct ipc_security_struct *isec; 6171 struct common_audit_data ad; 6172 u32 sid = current_sid(); 6173 int rc; 6174 6175 isec = selinux_ipc(sma); 6176 ipc_init_security(isec, SECCLASS_SEM); 6177 6178 ad.type = LSM_AUDIT_DATA_IPC; 6179 ad.u.ipc_id = sma->key; 6180 6181 rc = avc_has_perm(&selinux_state, 6182 sid, isec->sid, SECCLASS_SEM, 6183 SEM__CREATE, &ad); 6184 return rc; 6185 } 6186 6187 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6188 { 6189 struct ipc_security_struct *isec; 6190 struct common_audit_data ad; 6191 u32 sid = current_sid(); 6192 6193 isec = selinux_ipc(sma); 6194 6195 ad.type = LSM_AUDIT_DATA_IPC; 6196 ad.u.ipc_id = sma->key; 6197 6198 return avc_has_perm(&selinux_state, 6199 sid, isec->sid, SECCLASS_SEM, 6200 SEM__ASSOCIATE, &ad); 6201 } 6202 6203 /* Note, at this point, sma is locked down */ 6204 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6205 { 6206 int err; 6207 u32 perms; 6208 6209 switch (cmd) { 6210 case IPC_INFO: 6211 case SEM_INFO: 6212 /* No specific object, just general system-wide information. */ 6213 return avc_has_perm(&selinux_state, 6214 current_sid(), SECINITSID_KERNEL, 6215 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6216 case GETPID: 6217 case GETNCNT: 6218 case GETZCNT: 6219 perms = SEM__GETATTR; 6220 break; 6221 case GETVAL: 6222 case GETALL: 6223 perms = SEM__READ; 6224 break; 6225 case SETVAL: 6226 case SETALL: 6227 perms = SEM__WRITE; 6228 break; 6229 case IPC_RMID: 6230 perms = SEM__DESTROY; 6231 break; 6232 case IPC_SET: 6233 perms = SEM__SETATTR; 6234 break; 6235 case IPC_STAT: 6236 case SEM_STAT: 6237 case SEM_STAT_ANY: 6238 perms = SEM__GETATTR | SEM__ASSOCIATE; 6239 break; 6240 default: 6241 return 0; 6242 } 6243 6244 err = ipc_has_perm(sma, perms); 6245 return err; 6246 } 6247 6248 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6249 struct sembuf *sops, unsigned nsops, int alter) 6250 { 6251 u32 perms; 6252 6253 if (alter) 6254 perms = SEM__READ | SEM__WRITE; 6255 else 6256 perms = SEM__READ; 6257 6258 return ipc_has_perm(sma, perms); 6259 } 6260 6261 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6262 { 6263 u32 av = 0; 6264 6265 av = 0; 6266 if (flag & S_IRUGO) 6267 av |= IPC__UNIX_READ; 6268 if (flag & S_IWUGO) 6269 av |= IPC__UNIX_WRITE; 6270 6271 if (av == 0) 6272 return 0; 6273 6274 return ipc_has_perm(ipcp, av); 6275 } 6276 6277 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6278 { 6279 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6280 *secid = isec->sid; 6281 } 6282 6283 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6284 { 6285 if (inode) 6286 inode_doinit_with_dentry(inode, dentry); 6287 } 6288 6289 static int selinux_getprocattr(struct task_struct *p, 6290 char *name, char **value) 6291 { 6292 const struct task_security_struct *__tsec; 6293 u32 sid; 6294 int error; 6295 unsigned len; 6296 6297 rcu_read_lock(); 6298 __tsec = selinux_cred(__task_cred(p)); 6299 6300 if (current != p) { 6301 error = avc_has_perm(&selinux_state, 6302 current_sid(), __tsec->sid, 6303 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6304 if (error) 6305 goto bad; 6306 } 6307 6308 if (!strcmp(name, "current")) 6309 sid = __tsec->sid; 6310 else if (!strcmp(name, "prev")) 6311 sid = __tsec->osid; 6312 else if (!strcmp(name, "exec")) 6313 sid = __tsec->exec_sid; 6314 else if (!strcmp(name, "fscreate")) 6315 sid = __tsec->create_sid; 6316 else if (!strcmp(name, "keycreate")) 6317 sid = __tsec->keycreate_sid; 6318 else if (!strcmp(name, "sockcreate")) 6319 sid = __tsec->sockcreate_sid; 6320 else { 6321 error = -EINVAL; 6322 goto bad; 6323 } 6324 rcu_read_unlock(); 6325 6326 if (!sid) 6327 return 0; 6328 6329 error = security_sid_to_context(&selinux_state, sid, value, &len); 6330 if (error) 6331 return error; 6332 return len; 6333 6334 bad: 6335 rcu_read_unlock(); 6336 return error; 6337 } 6338 6339 static int selinux_setprocattr(const char *name, void *value, size_t size) 6340 { 6341 struct task_security_struct *tsec; 6342 struct cred *new; 6343 u32 mysid = current_sid(), sid = 0, ptsid; 6344 int error; 6345 char *str = value; 6346 6347 /* 6348 * Basic control over ability to set these attributes at all. 6349 */ 6350 if (!strcmp(name, "exec")) 6351 error = avc_has_perm(&selinux_state, 6352 mysid, mysid, SECCLASS_PROCESS, 6353 PROCESS__SETEXEC, NULL); 6354 else if (!strcmp(name, "fscreate")) 6355 error = avc_has_perm(&selinux_state, 6356 mysid, mysid, SECCLASS_PROCESS, 6357 PROCESS__SETFSCREATE, NULL); 6358 else if (!strcmp(name, "keycreate")) 6359 error = avc_has_perm(&selinux_state, 6360 mysid, mysid, SECCLASS_PROCESS, 6361 PROCESS__SETKEYCREATE, NULL); 6362 else if (!strcmp(name, "sockcreate")) 6363 error = avc_has_perm(&selinux_state, 6364 mysid, mysid, SECCLASS_PROCESS, 6365 PROCESS__SETSOCKCREATE, NULL); 6366 else if (!strcmp(name, "current")) 6367 error = avc_has_perm(&selinux_state, 6368 mysid, mysid, SECCLASS_PROCESS, 6369 PROCESS__SETCURRENT, NULL); 6370 else 6371 error = -EINVAL; 6372 if (error) 6373 return error; 6374 6375 /* Obtain a SID for the context, if one was specified. */ 6376 if (size && str[0] && str[0] != '\n') { 6377 if (str[size-1] == '\n') { 6378 str[size-1] = 0; 6379 size--; 6380 } 6381 error = security_context_to_sid(&selinux_state, value, size, 6382 &sid, GFP_KERNEL); 6383 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6384 if (!has_cap_mac_admin(true)) { 6385 struct audit_buffer *ab; 6386 size_t audit_size; 6387 6388 /* We strip a nul only if it is at the end, otherwise the 6389 * context contains a nul and we should audit that */ 6390 if (str[size - 1] == '\0') 6391 audit_size = size - 1; 6392 else 6393 audit_size = size; 6394 ab = audit_log_start(audit_context(), 6395 GFP_ATOMIC, 6396 AUDIT_SELINUX_ERR); 6397 audit_log_format(ab, "op=fscreate invalid_context="); 6398 audit_log_n_untrustedstring(ab, value, audit_size); 6399 audit_log_end(ab); 6400 6401 return error; 6402 } 6403 error = security_context_to_sid_force( 6404 &selinux_state, 6405 value, size, &sid); 6406 } 6407 if (error) 6408 return error; 6409 } 6410 6411 new = prepare_creds(); 6412 if (!new) 6413 return -ENOMEM; 6414 6415 /* Permission checking based on the specified context is 6416 performed during the actual operation (execve, 6417 open/mkdir/...), when we know the full context of the 6418 operation. See selinux_bprm_creds_for_exec for the execve 6419 checks and may_create for the file creation checks. The 6420 operation will then fail if the context is not permitted. */ 6421 tsec = selinux_cred(new); 6422 if (!strcmp(name, "exec")) { 6423 tsec->exec_sid = sid; 6424 } else if (!strcmp(name, "fscreate")) { 6425 tsec->create_sid = sid; 6426 } else if (!strcmp(name, "keycreate")) { 6427 if (sid) { 6428 error = avc_has_perm(&selinux_state, mysid, sid, 6429 SECCLASS_KEY, KEY__CREATE, NULL); 6430 if (error) 6431 goto abort_change; 6432 } 6433 tsec->keycreate_sid = sid; 6434 } else if (!strcmp(name, "sockcreate")) { 6435 tsec->sockcreate_sid = sid; 6436 } else if (!strcmp(name, "current")) { 6437 error = -EINVAL; 6438 if (sid == 0) 6439 goto abort_change; 6440 6441 /* Only allow single threaded processes to change context */ 6442 error = -EPERM; 6443 if (!current_is_single_threaded()) { 6444 error = security_bounded_transition(&selinux_state, 6445 tsec->sid, sid); 6446 if (error) 6447 goto abort_change; 6448 } 6449 6450 /* Check permissions for the transition. */ 6451 error = avc_has_perm(&selinux_state, 6452 tsec->sid, sid, SECCLASS_PROCESS, 6453 PROCESS__DYNTRANSITION, NULL); 6454 if (error) 6455 goto abort_change; 6456 6457 /* Check for ptracing, and update the task SID if ok. 6458 Otherwise, leave SID unchanged and fail. */ 6459 ptsid = ptrace_parent_sid(); 6460 if (ptsid != 0) { 6461 error = avc_has_perm(&selinux_state, 6462 ptsid, sid, SECCLASS_PROCESS, 6463 PROCESS__PTRACE, NULL); 6464 if (error) 6465 goto abort_change; 6466 } 6467 6468 tsec->sid = sid; 6469 } else { 6470 error = -EINVAL; 6471 goto abort_change; 6472 } 6473 6474 commit_creds(new); 6475 return size; 6476 6477 abort_change: 6478 abort_creds(new); 6479 return error; 6480 } 6481 6482 static int selinux_ismaclabel(const char *name) 6483 { 6484 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6485 } 6486 6487 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6488 { 6489 return security_sid_to_context(&selinux_state, secid, 6490 secdata, seclen); 6491 } 6492 6493 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6494 { 6495 return security_context_to_sid(&selinux_state, secdata, seclen, 6496 secid, GFP_KERNEL); 6497 } 6498 6499 static void selinux_release_secctx(char *secdata, u32 seclen) 6500 { 6501 kfree(secdata); 6502 } 6503 6504 static void selinux_inode_invalidate_secctx(struct inode *inode) 6505 { 6506 struct inode_security_struct *isec = selinux_inode(inode); 6507 6508 spin_lock(&isec->lock); 6509 isec->initialized = LABEL_INVALID; 6510 spin_unlock(&isec->lock); 6511 } 6512 6513 /* 6514 * called with inode->i_mutex locked 6515 */ 6516 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6517 { 6518 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6519 ctx, ctxlen, 0); 6520 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6521 return rc == -EOPNOTSUPP ? 0 : rc; 6522 } 6523 6524 /* 6525 * called with inode->i_mutex locked 6526 */ 6527 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6528 { 6529 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 6530 } 6531 6532 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6533 { 6534 int len = 0; 6535 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 6536 ctx, true); 6537 if (len < 0) 6538 return len; 6539 *ctxlen = len; 6540 return 0; 6541 } 6542 #ifdef CONFIG_KEYS 6543 6544 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6545 unsigned long flags) 6546 { 6547 const struct task_security_struct *tsec; 6548 struct key_security_struct *ksec; 6549 6550 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6551 if (!ksec) 6552 return -ENOMEM; 6553 6554 tsec = selinux_cred(cred); 6555 if (tsec->keycreate_sid) 6556 ksec->sid = tsec->keycreate_sid; 6557 else 6558 ksec->sid = tsec->sid; 6559 6560 k->security = ksec; 6561 return 0; 6562 } 6563 6564 static void selinux_key_free(struct key *k) 6565 { 6566 struct key_security_struct *ksec = k->security; 6567 6568 k->security = NULL; 6569 kfree(ksec); 6570 } 6571 6572 static int selinux_key_permission(key_ref_t key_ref, 6573 const struct cred *cred, 6574 enum key_need_perm need_perm) 6575 { 6576 struct key *key; 6577 struct key_security_struct *ksec; 6578 u32 perm, sid; 6579 6580 switch (need_perm) { 6581 case KEY_NEED_VIEW: 6582 perm = KEY__VIEW; 6583 break; 6584 case KEY_NEED_READ: 6585 perm = KEY__READ; 6586 break; 6587 case KEY_NEED_WRITE: 6588 perm = KEY__WRITE; 6589 break; 6590 case KEY_NEED_SEARCH: 6591 perm = KEY__SEARCH; 6592 break; 6593 case KEY_NEED_LINK: 6594 perm = KEY__LINK; 6595 break; 6596 case KEY_NEED_SETATTR: 6597 perm = KEY__SETATTR; 6598 break; 6599 case KEY_NEED_UNLINK: 6600 case KEY_SYSADMIN_OVERRIDE: 6601 case KEY_AUTHTOKEN_OVERRIDE: 6602 case KEY_DEFER_PERM_CHECK: 6603 return 0; 6604 default: 6605 WARN_ON(1); 6606 return -EPERM; 6607 6608 } 6609 6610 sid = cred_sid(cred); 6611 key = key_ref_to_ptr(key_ref); 6612 ksec = key->security; 6613 6614 return avc_has_perm(&selinux_state, 6615 sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6616 } 6617 6618 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6619 { 6620 struct key_security_struct *ksec = key->security; 6621 char *context = NULL; 6622 unsigned len; 6623 int rc; 6624 6625 rc = security_sid_to_context(&selinux_state, ksec->sid, 6626 &context, &len); 6627 if (!rc) 6628 rc = len; 6629 *_buffer = context; 6630 return rc; 6631 } 6632 6633 #ifdef CONFIG_KEY_NOTIFICATIONS 6634 static int selinux_watch_key(struct key *key) 6635 { 6636 struct key_security_struct *ksec = key->security; 6637 u32 sid = current_sid(); 6638 6639 return avc_has_perm(&selinux_state, 6640 sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6641 } 6642 #endif 6643 #endif 6644 6645 #ifdef CONFIG_SECURITY_INFINIBAND 6646 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6647 { 6648 struct common_audit_data ad; 6649 int err; 6650 u32 sid = 0; 6651 struct ib_security_struct *sec = ib_sec; 6652 struct lsm_ibpkey_audit ibpkey; 6653 6654 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6655 if (err) 6656 return err; 6657 6658 ad.type = LSM_AUDIT_DATA_IBPKEY; 6659 ibpkey.subnet_prefix = subnet_prefix; 6660 ibpkey.pkey = pkey_val; 6661 ad.u.ibpkey = &ibpkey; 6662 return avc_has_perm(&selinux_state, 6663 sec->sid, sid, 6664 SECCLASS_INFINIBAND_PKEY, 6665 INFINIBAND_PKEY__ACCESS, &ad); 6666 } 6667 6668 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6669 u8 port_num) 6670 { 6671 struct common_audit_data ad; 6672 int err; 6673 u32 sid = 0; 6674 struct ib_security_struct *sec = ib_sec; 6675 struct lsm_ibendport_audit ibendport; 6676 6677 err = security_ib_endport_sid(&selinux_state, dev_name, port_num, 6678 &sid); 6679 6680 if (err) 6681 return err; 6682 6683 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6684 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name)); 6685 ibendport.port = port_num; 6686 ad.u.ibendport = &ibendport; 6687 return avc_has_perm(&selinux_state, 6688 sec->sid, sid, 6689 SECCLASS_INFINIBAND_ENDPORT, 6690 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6691 } 6692 6693 static int selinux_ib_alloc_security(void **ib_sec) 6694 { 6695 struct ib_security_struct *sec; 6696 6697 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6698 if (!sec) 6699 return -ENOMEM; 6700 sec->sid = current_sid(); 6701 6702 *ib_sec = sec; 6703 return 0; 6704 } 6705 6706 static void selinux_ib_free_security(void *ib_sec) 6707 { 6708 kfree(ib_sec); 6709 } 6710 #endif 6711 6712 #ifdef CONFIG_BPF_SYSCALL 6713 static int selinux_bpf(int cmd, union bpf_attr *attr, 6714 unsigned int size) 6715 { 6716 u32 sid = current_sid(); 6717 int ret; 6718 6719 switch (cmd) { 6720 case BPF_MAP_CREATE: 6721 ret = avc_has_perm(&selinux_state, 6722 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6723 NULL); 6724 break; 6725 case BPF_PROG_LOAD: 6726 ret = avc_has_perm(&selinux_state, 6727 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6728 NULL); 6729 break; 6730 default: 6731 ret = 0; 6732 break; 6733 } 6734 6735 return ret; 6736 } 6737 6738 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6739 { 6740 u32 av = 0; 6741 6742 if (fmode & FMODE_READ) 6743 av |= BPF__MAP_READ; 6744 if (fmode & FMODE_WRITE) 6745 av |= BPF__MAP_WRITE; 6746 return av; 6747 } 6748 6749 /* This function will check the file pass through unix socket or binder to see 6750 * if it is a bpf related object. And apply correspinding checks on the bpf 6751 * object based on the type. The bpf maps and programs, not like other files and 6752 * socket, are using a shared anonymous inode inside the kernel as their inode. 6753 * So checking that inode cannot identify if the process have privilege to 6754 * access the bpf object and that's why we have to add this additional check in 6755 * selinux_file_receive and selinux_binder_transfer_files. 6756 */ 6757 static int bpf_fd_pass(struct file *file, u32 sid) 6758 { 6759 struct bpf_security_struct *bpfsec; 6760 struct bpf_prog *prog; 6761 struct bpf_map *map; 6762 int ret; 6763 6764 if (file->f_op == &bpf_map_fops) { 6765 map = file->private_data; 6766 bpfsec = map->security; 6767 ret = avc_has_perm(&selinux_state, 6768 sid, bpfsec->sid, SECCLASS_BPF, 6769 bpf_map_fmode_to_av(file->f_mode), NULL); 6770 if (ret) 6771 return ret; 6772 } else if (file->f_op == &bpf_prog_fops) { 6773 prog = file->private_data; 6774 bpfsec = prog->aux->security; 6775 ret = avc_has_perm(&selinux_state, 6776 sid, bpfsec->sid, SECCLASS_BPF, 6777 BPF__PROG_RUN, NULL); 6778 if (ret) 6779 return ret; 6780 } 6781 return 0; 6782 } 6783 6784 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6785 { 6786 u32 sid = current_sid(); 6787 struct bpf_security_struct *bpfsec; 6788 6789 bpfsec = map->security; 6790 return avc_has_perm(&selinux_state, 6791 sid, bpfsec->sid, SECCLASS_BPF, 6792 bpf_map_fmode_to_av(fmode), NULL); 6793 } 6794 6795 static int selinux_bpf_prog(struct bpf_prog *prog) 6796 { 6797 u32 sid = current_sid(); 6798 struct bpf_security_struct *bpfsec; 6799 6800 bpfsec = prog->aux->security; 6801 return avc_has_perm(&selinux_state, 6802 sid, bpfsec->sid, SECCLASS_BPF, 6803 BPF__PROG_RUN, NULL); 6804 } 6805 6806 static int selinux_bpf_map_alloc(struct bpf_map *map) 6807 { 6808 struct bpf_security_struct *bpfsec; 6809 6810 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6811 if (!bpfsec) 6812 return -ENOMEM; 6813 6814 bpfsec->sid = current_sid(); 6815 map->security = bpfsec; 6816 6817 return 0; 6818 } 6819 6820 static void selinux_bpf_map_free(struct bpf_map *map) 6821 { 6822 struct bpf_security_struct *bpfsec = map->security; 6823 6824 map->security = NULL; 6825 kfree(bpfsec); 6826 } 6827 6828 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6829 { 6830 struct bpf_security_struct *bpfsec; 6831 6832 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6833 if (!bpfsec) 6834 return -ENOMEM; 6835 6836 bpfsec->sid = current_sid(); 6837 aux->security = bpfsec; 6838 6839 return 0; 6840 } 6841 6842 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6843 { 6844 struct bpf_security_struct *bpfsec = aux->security; 6845 6846 aux->security = NULL; 6847 kfree(bpfsec); 6848 } 6849 #endif 6850 6851 static int selinux_lockdown(enum lockdown_reason what) 6852 { 6853 struct common_audit_data ad; 6854 u32 sid = current_sid(); 6855 int invalid_reason = (what <= LOCKDOWN_NONE) || 6856 (what == LOCKDOWN_INTEGRITY_MAX) || 6857 (what >= LOCKDOWN_CONFIDENTIALITY_MAX); 6858 6859 if (WARN(invalid_reason, "Invalid lockdown reason")) { 6860 audit_log(audit_context(), 6861 GFP_ATOMIC, AUDIT_SELINUX_ERR, 6862 "lockdown_reason=invalid"); 6863 return -EINVAL; 6864 } 6865 6866 ad.type = LSM_AUDIT_DATA_LOCKDOWN; 6867 ad.u.reason = what; 6868 6869 if (what <= LOCKDOWN_INTEGRITY_MAX) 6870 return avc_has_perm(&selinux_state, 6871 sid, sid, SECCLASS_LOCKDOWN, 6872 LOCKDOWN__INTEGRITY, &ad); 6873 else 6874 return avc_has_perm(&selinux_state, 6875 sid, sid, SECCLASS_LOCKDOWN, 6876 LOCKDOWN__CONFIDENTIALITY, &ad); 6877 } 6878 6879 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = { 6880 .lbs_cred = sizeof(struct task_security_struct), 6881 .lbs_file = sizeof(struct file_security_struct), 6882 .lbs_inode = sizeof(struct inode_security_struct), 6883 .lbs_ipc = sizeof(struct ipc_security_struct), 6884 .lbs_msg_msg = sizeof(struct msg_security_struct), 6885 }; 6886 6887 #ifdef CONFIG_PERF_EVENTS 6888 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6889 { 6890 u32 requested, sid = current_sid(); 6891 6892 if (type == PERF_SECURITY_OPEN) 6893 requested = PERF_EVENT__OPEN; 6894 else if (type == PERF_SECURITY_CPU) 6895 requested = PERF_EVENT__CPU; 6896 else if (type == PERF_SECURITY_KERNEL) 6897 requested = PERF_EVENT__KERNEL; 6898 else if (type == PERF_SECURITY_TRACEPOINT) 6899 requested = PERF_EVENT__TRACEPOINT; 6900 else 6901 return -EINVAL; 6902 6903 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT, 6904 requested, NULL); 6905 } 6906 6907 static int selinux_perf_event_alloc(struct perf_event *event) 6908 { 6909 struct perf_event_security_struct *perfsec; 6910 6911 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6912 if (!perfsec) 6913 return -ENOMEM; 6914 6915 perfsec->sid = current_sid(); 6916 event->security = perfsec; 6917 6918 return 0; 6919 } 6920 6921 static void selinux_perf_event_free(struct perf_event *event) 6922 { 6923 struct perf_event_security_struct *perfsec = event->security; 6924 6925 event->security = NULL; 6926 kfree(perfsec); 6927 } 6928 6929 static int selinux_perf_event_read(struct perf_event *event) 6930 { 6931 struct perf_event_security_struct *perfsec = event->security; 6932 u32 sid = current_sid(); 6933 6934 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6935 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6936 } 6937 6938 static int selinux_perf_event_write(struct perf_event *event) 6939 { 6940 struct perf_event_security_struct *perfsec = event->security; 6941 u32 sid = current_sid(); 6942 6943 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6944 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6945 } 6946 #endif 6947 6948 /* 6949 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6950 * 1. any hooks that don't belong to (2.) or (3.) below, 6951 * 2. hooks that both access structures allocated by other hooks, and allocate 6952 * structures that can be later accessed by other hooks (mostly "cloning" 6953 * hooks), 6954 * 3. hooks that only allocate structures that can be later accessed by other 6955 * hooks ("allocating" hooks). 6956 * 6957 * Please follow block comment delimiters in the list to keep this order. 6958 * 6959 * This ordering is needed for SELinux runtime disable to work at least somewhat 6960 * safely. Breaking the ordering rules above might lead to NULL pointer derefs 6961 * when disabling SELinux at runtime. 6962 */ 6963 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { 6964 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6965 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6966 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6967 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6968 6969 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6970 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6971 LSM_HOOK_INIT(capget, selinux_capget), 6972 LSM_HOOK_INIT(capset, selinux_capset), 6973 LSM_HOOK_INIT(capable, selinux_capable), 6974 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6975 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6976 LSM_HOOK_INIT(syslog, selinux_syslog), 6977 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6978 6979 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6980 6981 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 6982 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6983 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6984 6985 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), 6986 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 6987 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6988 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6989 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6990 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6991 LSM_HOOK_INIT(sb_mount, selinux_mount), 6992 LSM_HOOK_INIT(sb_umount, selinux_umount), 6993 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6994 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6995 6996 LSM_HOOK_INIT(move_mount, selinux_move_mount), 6997 6998 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6999 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7000 7001 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7002 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7003 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7004 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7005 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7006 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7007 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7008 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7009 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7010 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7011 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7012 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7013 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7014 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7015 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7016 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7017 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7018 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7019 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7020 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7021 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7022 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7023 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7024 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7025 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7026 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7027 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7028 7029 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7030 7031 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7032 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7033 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7034 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7035 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7036 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7037 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7038 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7039 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7040 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7041 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7042 7043 LSM_HOOK_INIT(file_open, selinux_file_open), 7044 7045 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7046 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7047 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7048 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7049 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7050 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7051 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7052 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7053 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7054 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7055 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7056 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7057 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), 7058 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7059 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7060 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7061 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7062 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7063 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7064 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7065 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7066 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7067 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7068 7069 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7070 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7071 7072 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7073 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7074 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7075 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7076 7077 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7078 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7079 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7080 7081 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7082 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7083 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7084 7085 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7086 7087 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7088 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7089 7090 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7091 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7092 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7093 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7094 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7095 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7096 7097 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7098 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7099 7100 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7101 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7102 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7103 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7104 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7105 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7106 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7107 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7108 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7109 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7110 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7111 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7112 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7113 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7114 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7115 LSM_HOOK_INIT(socket_getpeersec_stream, 7116 selinux_socket_getpeersec_stream), 7117 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7118 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7119 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7120 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7121 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7122 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7123 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7124 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7125 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7126 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7127 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7128 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7129 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7130 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7131 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7132 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7133 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7134 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7135 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7136 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7137 #ifdef CONFIG_SECURITY_INFINIBAND 7138 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7139 LSM_HOOK_INIT(ib_endport_manage_subnet, 7140 selinux_ib_endport_manage_subnet), 7141 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7142 #endif 7143 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7144 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7145 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7146 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7147 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7148 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7149 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7150 selinux_xfrm_state_pol_flow_match), 7151 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7152 #endif 7153 7154 #ifdef CONFIG_KEYS 7155 LSM_HOOK_INIT(key_free, selinux_key_free), 7156 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7157 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7158 #ifdef CONFIG_KEY_NOTIFICATIONS 7159 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7160 #endif 7161 #endif 7162 7163 #ifdef CONFIG_AUDIT 7164 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7165 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7166 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7167 #endif 7168 7169 #ifdef CONFIG_BPF_SYSCALL 7170 LSM_HOOK_INIT(bpf, selinux_bpf), 7171 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7172 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7173 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7174 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7175 #endif 7176 7177 #ifdef CONFIG_PERF_EVENTS 7178 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7179 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7180 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7181 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7182 #endif 7183 7184 LSM_HOOK_INIT(locked_down, selinux_lockdown), 7185 7186 /* 7187 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7188 */ 7189 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7190 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7191 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7192 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt), 7193 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7194 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7195 #endif 7196 7197 /* 7198 * PUT "ALLOCATING" HOOKS HERE 7199 */ 7200 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7201 LSM_HOOK_INIT(msg_queue_alloc_security, 7202 selinux_msg_queue_alloc_security), 7203 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7204 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7205 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7206 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7207 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7208 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7209 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7210 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7211 #ifdef CONFIG_SECURITY_INFINIBAND 7212 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7213 #endif 7214 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7215 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7216 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7217 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7218 selinux_xfrm_state_alloc_acquire), 7219 #endif 7220 #ifdef CONFIG_KEYS 7221 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7222 #endif 7223 #ifdef CONFIG_AUDIT 7224 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7225 #endif 7226 #ifdef CONFIG_BPF_SYSCALL 7227 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7228 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7229 #endif 7230 #ifdef CONFIG_PERF_EVENTS 7231 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7232 #endif 7233 }; 7234 7235 static __init int selinux_init(void) 7236 { 7237 pr_info("SELinux: Initializing.\n"); 7238 7239 memset(&selinux_state, 0, sizeof(selinux_state)); 7240 enforcing_set(&selinux_state, selinux_enforcing_boot); 7241 checkreqprot_set(&selinux_state, selinux_checkreqprot_boot); 7242 selinux_avc_init(&selinux_state.avc); 7243 mutex_init(&selinux_state.status_lock); 7244 mutex_init(&selinux_state.policy_mutex); 7245 7246 /* Set the security state for the initial task. */ 7247 cred_init_security(); 7248 7249 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7250 7251 avc_init(); 7252 7253 avtab_cache_init(); 7254 7255 ebitmap_cache_init(); 7256 7257 hashtab_cache_init(); 7258 7259 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7260 7261 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7262 panic("SELinux: Unable to register AVC netcache callback\n"); 7263 7264 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7265 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7266 7267 if (selinux_enforcing_boot) 7268 pr_debug("SELinux: Starting in enforcing mode\n"); 7269 else 7270 pr_debug("SELinux: Starting in permissive mode\n"); 7271 7272 fs_validate_description("selinux", selinux_fs_parameters); 7273 7274 return 0; 7275 } 7276 7277 static void delayed_superblock_init(struct super_block *sb, void *unused) 7278 { 7279 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7280 } 7281 7282 void selinux_complete_init(void) 7283 { 7284 pr_debug("SELinux: Completing initialization.\n"); 7285 7286 /* Set up any superblocks initialized prior to the policy load. */ 7287 pr_debug("SELinux: Setting up existing superblocks.\n"); 7288 iterate_supers(delayed_superblock_init, NULL); 7289 } 7290 7291 /* SELinux requires early initialization in order to label 7292 all processes and objects when they are created. */ 7293 DEFINE_LSM(selinux) = { 7294 .name = "selinux", 7295 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7296 .enabled = &selinux_enabled_boot, 7297 .blobs = &selinux_blob_sizes, 7298 .init = selinux_init, 7299 }; 7300 7301 #if defined(CONFIG_NETFILTER) 7302 7303 static const struct nf_hook_ops selinux_nf_ops[] = { 7304 { 7305 .hook = selinux_ipv4_postroute, 7306 .pf = NFPROTO_IPV4, 7307 .hooknum = NF_INET_POST_ROUTING, 7308 .priority = NF_IP_PRI_SELINUX_LAST, 7309 }, 7310 { 7311 .hook = selinux_ipv4_forward, 7312 .pf = NFPROTO_IPV4, 7313 .hooknum = NF_INET_FORWARD, 7314 .priority = NF_IP_PRI_SELINUX_FIRST, 7315 }, 7316 { 7317 .hook = selinux_ipv4_output, 7318 .pf = NFPROTO_IPV4, 7319 .hooknum = NF_INET_LOCAL_OUT, 7320 .priority = NF_IP_PRI_SELINUX_FIRST, 7321 }, 7322 #if IS_ENABLED(CONFIG_IPV6) 7323 { 7324 .hook = selinux_ipv6_postroute, 7325 .pf = NFPROTO_IPV6, 7326 .hooknum = NF_INET_POST_ROUTING, 7327 .priority = NF_IP6_PRI_SELINUX_LAST, 7328 }, 7329 { 7330 .hook = selinux_ipv6_forward, 7331 .pf = NFPROTO_IPV6, 7332 .hooknum = NF_INET_FORWARD, 7333 .priority = NF_IP6_PRI_SELINUX_FIRST, 7334 }, 7335 { 7336 .hook = selinux_ipv6_output, 7337 .pf = NFPROTO_IPV6, 7338 .hooknum = NF_INET_LOCAL_OUT, 7339 .priority = NF_IP6_PRI_SELINUX_FIRST, 7340 }, 7341 #endif /* IPV6 */ 7342 }; 7343 7344 static int __net_init selinux_nf_register(struct net *net) 7345 { 7346 return nf_register_net_hooks(net, selinux_nf_ops, 7347 ARRAY_SIZE(selinux_nf_ops)); 7348 } 7349 7350 static void __net_exit selinux_nf_unregister(struct net *net) 7351 { 7352 nf_unregister_net_hooks(net, selinux_nf_ops, 7353 ARRAY_SIZE(selinux_nf_ops)); 7354 } 7355 7356 static struct pernet_operations selinux_net_ops = { 7357 .init = selinux_nf_register, 7358 .exit = selinux_nf_unregister, 7359 }; 7360 7361 static int __init selinux_nf_ip_init(void) 7362 { 7363 int err; 7364 7365 if (!selinux_enabled_boot) 7366 return 0; 7367 7368 pr_debug("SELinux: Registering netfilter hooks\n"); 7369 7370 err = register_pernet_subsys(&selinux_net_ops); 7371 if (err) 7372 panic("SELinux: register_pernet_subsys: error %d\n", err); 7373 7374 return 0; 7375 } 7376 __initcall(selinux_nf_ip_init); 7377 7378 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7379 static void selinux_nf_ip_exit(void) 7380 { 7381 pr_debug("SELinux: Unregistering netfilter hooks\n"); 7382 7383 unregister_pernet_subsys(&selinux_net_ops); 7384 } 7385 #endif 7386 7387 #else /* CONFIG_NETFILTER */ 7388 7389 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7390 #define selinux_nf_ip_exit() 7391 #endif 7392 7393 #endif /* CONFIG_NETFILTER */ 7394 7395 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7396 int selinux_disable(struct selinux_state *state) 7397 { 7398 if (selinux_initialized(state)) { 7399 /* Not permitted after initial policy load. */ 7400 return -EINVAL; 7401 } 7402 7403 if (selinux_disabled(state)) { 7404 /* Only do this once. */ 7405 return -EINVAL; 7406 } 7407 7408 selinux_mark_disabled(state); 7409 7410 pr_info("SELinux: Disabled at runtime.\n"); 7411 7412 /* 7413 * Unregister netfilter hooks. 7414 * Must be done before security_delete_hooks() to avoid breaking 7415 * runtime disable. 7416 */ 7417 selinux_nf_ip_exit(); 7418 7419 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 7420 7421 /* Try to destroy the avc node cache */ 7422 avc_disable(); 7423 7424 /* Unregister selinuxfs. */ 7425 exit_sel_fs(); 7426 7427 return 0; 7428 } 7429 #endif 7430