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 = sbsec->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 = sbsec->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; 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; 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 (!sid || rc) { 1537 isec->initialized = LABEL_INVALID; 1538 goto out_unlock; 1539 } 1540 1541 isec->initialized = LABEL_INITIALIZED; 1542 isec->sid = sid; 1543 } 1544 1545 out_unlock: 1546 spin_unlock(&isec->lock); 1547 return rc; 1548 } 1549 1550 /* Convert a Linux signal to an access vector. */ 1551 static inline u32 signal_to_av(int sig) 1552 { 1553 u32 perm = 0; 1554 1555 switch (sig) { 1556 case SIGCHLD: 1557 /* Commonly granted from child to parent. */ 1558 perm = PROCESS__SIGCHLD; 1559 break; 1560 case SIGKILL: 1561 /* Cannot be caught or ignored */ 1562 perm = PROCESS__SIGKILL; 1563 break; 1564 case SIGSTOP: 1565 /* Cannot be caught or ignored */ 1566 perm = PROCESS__SIGSTOP; 1567 break; 1568 default: 1569 /* All other signals. */ 1570 perm = PROCESS__SIGNAL; 1571 break; 1572 } 1573 1574 return perm; 1575 } 1576 1577 #if CAP_LAST_CAP > 63 1578 #error Fix SELinux to handle capabilities > 63. 1579 #endif 1580 1581 /* Check whether a task is allowed to use a capability. */ 1582 static int cred_has_capability(const struct cred *cred, 1583 int cap, unsigned int opts, bool initns) 1584 { 1585 struct common_audit_data ad; 1586 struct av_decision avd; 1587 u16 sclass; 1588 u32 sid = cred_sid(cred); 1589 u32 av = CAP_TO_MASK(cap); 1590 int rc; 1591 1592 ad.type = LSM_AUDIT_DATA_CAP; 1593 ad.u.cap = cap; 1594 1595 switch (CAP_TO_INDEX(cap)) { 1596 case 0: 1597 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1598 break; 1599 case 1: 1600 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1601 break; 1602 default: 1603 pr_err("SELinux: out of range capability %d\n", cap); 1604 BUG(); 1605 return -EINVAL; 1606 } 1607 1608 rc = avc_has_perm_noaudit(&selinux_state, 1609 sid, sid, sclass, av, 0, &avd); 1610 if (!(opts & CAP_OPT_NOAUDIT)) { 1611 int rc2 = avc_audit(&selinux_state, 1612 sid, sid, sclass, av, &avd, rc, &ad, 0); 1613 if (rc2) 1614 return rc2; 1615 } 1616 return rc; 1617 } 1618 1619 /* Check whether a task has a particular permission to an inode. 1620 The 'adp' parameter is optional and allows other audit 1621 data to be passed (e.g. the dentry). */ 1622 static int inode_has_perm(const struct cred *cred, 1623 struct inode *inode, 1624 u32 perms, 1625 struct common_audit_data *adp) 1626 { 1627 struct inode_security_struct *isec; 1628 u32 sid; 1629 1630 validate_creds(cred); 1631 1632 if (unlikely(IS_PRIVATE(inode))) 1633 return 0; 1634 1635 sid = cred_sid(cred); 1636 isec = selinux_inode(inode); 1637 1638 return avc_has_perm(&selinux_state, 1639 sid, isec->sid, isec->sclass, perms, adp); 1640 } 1641 1642 /* Same as inode_has_perm, but pass explicit audit data containing 1643 the dentry to help the auditing code to more easily generate the 1644 pathname if needed. */ 1645 static inline int dentry_has_perm(const struct cred *cred, 1646 struct dentry *dentry, 1647 u32 av) 1648 { 1649 struct inode *inode = d_backing_inode(dentry); 1650 struct common_audit_data ad; 1651 1652 ad.type = LSM_AUDIT_DATA_DENTRY; 1653 ad.u.dentry = dentry; 1654 __inode_security_revalidate(inode, dentry, true); 1655 return inode_has_perm(cred, inode, av, &ad); 1656 } 1657 1658 /* Same as inode_has_perm, but pass explicit audit data containing 1659 the path to help the auditing code to more easily generate the 1660 pathname if needed. */ 1661 static inline int path_has_perm(const struct cred *cred, 1662 const struct path *path, 1663 u32 av) 1664 { 1665 struct inode *inode = d_backing_inode(path->dentry); 1666 struct common_audit_data ad; 1667 1668 ad.type = LSM_AUDIT_DATA_PATH; 1669 ad.u.path = *path; 1670 __inode_security_revalidate(inode, path->dentry, true); 1671 return inode_has_perm(cred, inode, av, &ad); 1672 } 1673 1674 /* Same as path_has_perm, but uses the inode from the file struct. */ 1675 static inline int file_path_has_perm(const struct cred *cred, 1676 struct file *file, 1677 u32 av) 1678 { 1679 struct common_audit_data ad; 1680 1681 ad.type = LSM_AUDIT_DATA_FILE; 1682 ad.u.file = file; 1683 return inode_has_perm(cred, file_inode(file), av, &ad); 1684 } 1685 1686 #ifdef CONFIG_BPF_SYSCALL 1687 static int bpf_fd_pass(struct file *file, u32 sid); 1688 #endif 1689 1690 /* Check whether a task can use an open file descriptor to 1691 access an inode in a given way. Check access to the 1692 descriptor itself, and then use dentry_has_perm to 1693 check a particular permission to the file. 1694 Access to the descriptor is implicitly granted if it 1695 has the same SID as the process. If av is zero, then 1696 access to the file is not checked, e.g. for cases 1697 where only the descriptor is affected like seek. */ 1698 static int file_has_perm(const struct cred *cred, 1699 struct file *file, 1700 u32 av) 1701 { 1702 struct file_security_struct *fsec = selinux_file(file); 1703 struct inode *inode = file_inode(file); 1704 struct common_audit_data ad; 1705 u32 sid = cred_sid(cred); 1706 int rc; 1707 1708 ad.type = LSM_AUDIT_DATA_FILE; 1709 ad.u.file = file; 1710 1711 if (sid != fsec->sid) { 1712 rc = avc_has_perm(&selinux_state, 1713 sid, fsec->sid, 1714 SECCLASS_FD, 1715 FD__USE, 1716 &ad); 1717 if (rc) 1718 goto out; 1719 } 1720 1721 #ifdef CONFIG_BPF_SYSCALL 1722 rc = bpf_fd_pass(file, cred_sid(cred)); 1723 if (rc) 1724 return rc; 1725 #endif 1726 1727 /* av is zero if only checking access to the descriptor. */ 1728 rc = 0; 1729 if (av) 1730 rc = inode_has_perm(cred, inode, av, &ad); 1731 1732 out: 1733 return rc; 1734 } 1735 1736 /* 1737 * Determine the label for an inode that might be unioned. 1738 */ 1739 static int 1740 selinux_determine_inode_label(const struct task_security_struct *tsec, 1741 struct inode *dir, 1742 const struct qstr *name, u16 tclass, 1743 u32 *_new_isid) 1744 { 1745 const struct superblock_security_struct *sbsec = dir->i_sb->s_security; 1746 1747 if ((sbsec->flags & SE_SBINITIALIZED) && 1748 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1749 *_new_isid = sbsec->mntpoint_sid; 1750 } else if ((sbsec->flags & SBLABEL_MNT) && 1751 tsec->create_sid) { 1752 *_new_isid = tsec->create_sid; 1753 } else { 1754 const struct inode_security_struct *dsec = inode_security(dir); 1755 return security_transition_sid(&selinux_state, tsec->sid, 1756 dsec->sid, tclass, 1757 name, _new_isid); 1758 } 1759 1760 return 0; 1761 } 1762 1763 /* Check whether a task can create a file. */ 1764 static int may_create(struct inode *dir, 1765 struct dentry *dentry, 1766 u16 tclass) 1767 { 1768 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1769 struct inode_security_struct *dsec; 1770 struct superblock_security_struct *sbsec; 1771 u32 sid, newsid; 1772 struct common_audit_data ad; 1773 int rc; 1774 1775 dsec = inode_security(dir); 1776 sbsec = dir->i_sb->s_security; 1777 1778 sid = tsec->sid; 1779 1780 ad.type = LSM_AUDIT_DATA_DENTRY; 1781 ad.u.dentry = dentry; 1782 1783 rc = avc_has_perm(&selinux_state, 1784 sid, dsec->sid, SECCLASS_DIR, 1785 DIR__ADD_NAME | DIR__SEARCH, 1786 &ad); 1787 if (rc) 1788 return rc; 1789 1790 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1791 &newsid); 1792 if (rc) 1793 return rc; 1794 1795 rc = avc_has_perm(&selinux_state, 1796 sid, newsid, tclass, FILE__CREATE, &ad); 1797 if (rc) 1798 return rc; 1799 1800 return avc_has_perm(&selinux_state, 1801 newsid, sbsec->sid, 1802 SECCLASS_FILESYSTEM, 1803 FILESYSTEM__ASSOCIATE, &ad); 1804 } 1805 1806 #define MAY_LINK 0 1807 #define MAY_UNLINK 1 1808 #define MAY_RMDIR 2 1809 1810 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1811 static int may_link(struct inode *dir, 1812 struct dentry *dentry, 1813 int kind) 1814 1815 { 1816 struct inode_security_struct *dsec, *isec; 1817 struct common_audit_data ad; 1818 u32 sid = current_sid(); 1819 u32 av; 1820 int rc; 1821 1822 dsec = inode_security(dir); 1823 isec = backing_inode_security(dentry); 1824 1825 ad.type = LSM_AUDIT_DATA_DENTRY; 1826 ad.u.dentry = dentry; 1827 1828 av = DIR__SEARCH; 1829 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1830 rc = avc_has_perm(&selinux_state, 1831 sid, dsec->sid, SECCLASS_DIR, av, &ad); 1832 if (rc) 1833 return rc; 1834 1835 switch (kind) { 1836 case MAY_LINK: 1837 av = FILE__LINK; 1838 break; 1839 case MAY_UNLINK: 1840 av = FILE__UNLINK; 1841 break; 1842 case MAY_RMDIR: 1843 av = DIR__RMDIR; 1844 break; 1845 default: 1846 pr_warn("SELinux: %s: unrecognized kind %d\n", 1847 __func__, kind); 1848 return 0; 1849 } 1850 1851 rc = avc_has_perm(&selinux_state, 1852 sid, isec->sid, isec->sclass, av, &ad); 1853 return rc; 1854 } 1855 1856 static inline int may_rename(struct inode *old_dir, 1857 struct dentry *old_dentry, 1858 struct inode *new_dir, 1859 struct dentry *new_dentry) 1860 { 1861 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1862 struct common_audit_data ad; 1863 u32 sid = current_sid(); 1864 u32 av; 1865 int old_is_dir, new_is_dir; 1866 int rc; 1867 1868 old_dsec = inode_security(old_dir); 1869 old_isec = backing_inode_security(old_dentry); 1870 old_is_dir = d_is_dir(old_dentry); 1871 new_dsec = inode_security(new_dir); 1872 1873 ad.type = LSM_AUDIT_DATA_DENTRY; 1874 1875 ad.u.dentry = old_dentry; 1876 rc = avc_has_perm(&selinux_state, 1877 sid, old_dsec->sid, SECCLASS_DIR, 1878 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1879 if (rc) 1880 return rc; 1881 rc = avc_has_perm(&selinux_state, 1882 sid, old_isec->sid, 1883 old_isec->sclass, FILE__RENAME, &ad); 1884 if (rc) 1885 return rc; 1886 if (old_is_dir && new_dir != old_dir) { 1887 rc = avc_has_perm(&selinux_state, 1888 sid, old_isec->sid, 1889 old_isec->sclass, DIR__REPARENT, &ad); 1890 if (rc) 1891 return rc; 1892 } 1893 1894 ad.u.dentry = new_dentry; 1895 av = DIR__ADD_NAME | DIR__SEARCH; 1896 if (d_is_positive(new_dentry)) 1897 av |= DIR__REMOVE_NAME; 1898 rc = avc_has_perm(&selinux_state, 1899 sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1900 if (rc) 1901 return rc; 1902 if (d_is_positive(new_dentry)) { 1903 new_isec = backing_inode_security(new_dentry); 1904 new_is_dir = d_is_dir(new_dentry); 1905 rc = avc_has_perm(&selinux_state, 1906 sid, new_isec->sid, 1907 new_isec->sclass, 1908 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1909 if (rc) 1910 return rc; 1911 } 1912 1913 return 0; 1914 } 1915 1916 /* Check whether a task can perform a filesystem operation. */ 1917 static int superblock_has_perm(const struct cred *cred, 1918 struct super_block *sb, 1919 u32 perms, 1920 struct common_audit_data *ad) 1921 { 1922 struct superblock_security_struct *sbsec; 1923 u32 sid = cred_sid(cred); 1924 1925 sbsec = sb->s_security; 1926 return avc_has_perm(&selinux_state, 1927 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1928 } 1929 1930 /* Convert a Linux mode and permission mask to an access vector. */ 1931 static inline u32 file_mask_to_av(int mode, int mask) 1932 { 1933 u32 av = 0; 1934 1935 if (!S_ISDIR(mode)) { 1936 if (mask & MAY_EXEC) 1937 av |= FILE__EXECUTE; 1938 if (mask & MAY_READ) 1939 av |= FILE__READ; 1940 1941 if (mask & MAY_APPEND) 1942 av |= FILE__APPEND; 1943 else if (mask & MAY_WRITE) 1944 av |= FILE__WRITE; 1945 1946 } else { 1947 if (mask & MAY_EXEC) 1948 av |= DIR__SEARCH; 1949 if (mask & MAY_WRITE) 1950 av |= DIR__WRITE; 1951 if (mask & MAY_READ) 1952 av |= DIR__READ; 1953 } 1954 1955 return av; 1956 } 1957 1958 /* Convert a Linux file to an access vector. */ 1959 static inline u32 file_to_av(struct file *file) 1960 { 1961 u32 av = 0; 1962 1963 if (file->f_mode & FMODE_READ) 1964 av |= FILE__READ; 1965 if (file->f_mode & FMODE_WRITE) { 1966 if (file->f_flags & O_APPEND) 1967 av |= FILE__APPEND; 1968 else 1969 av |= FILE__WRITE; 1970 } 1971 if (!av) { 1972 /* 1973 * Special file opened with flags 3 for ioctl-only use. 1974 */ 1975 av = FILE__IOCTL; 1976 } 1977 1978 return av; 1979 } 1980 1981 /* 1982 * Convert a file to an access vector and include the correct 1983 * open permission. 1984 */ 1985 static inline u32 open_file_to_av(struct file *file) 1986 { 1987 u32 av = file_to_av(file); 1988 struct inode *inode = file_inode(file); 1989 1990 if (selinux_policycap_openperm() && 1991 inode->i_sb->s_magic != SOCKFS_MAGIC) 1992 av |= FILE__OPEN; 1993 1994 return av; 1995 } 1996 1997 /* Hook functions begin here. */ 1998 1999 static int selinux_binder_set_context_mgr(struct task_struct *mgr) 2000 { 2001 u32 mysid = current_sid(); 2002 u32 mgrsid = task_sid(mgr); 2003 2004 return avc_has_perm(&selinux_state, 2005 mysid, mgrsid, SECCLASS_BINDER, 2006 BINDER__SET_CONTEXT_MGR, NULL); 2007 } 2008 2009 static int selinux_binder_transaction(struct task_struct *from, 2010 struct task_struct *to) 2011 { 2012 u32 mysid = current_sid(); 2013 u32 fromsid = task_sid(from); 2014 u32 tosid = task_sid(to); 2015 int rc; 2016 2017 if (mysid != fromsid) { 2018 rc = avc_has_perm(&selinux_state, 2019 mysid, fromsid, SECCLASS_BINDER, 2020 BINDER__IMPERSONATE, NULL); 2021 if (rc) 2022 return rc; 2023 } 2024 2025 return avc_has_perm(&selinux_state, 2026 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, 2027 NULL); 2028 } 2029 2030 static int selinux_binder_transfer_binder(struct task_struct *from, 2031 struct task_struct *to) 2032 { 2033 u32 fromsid = task_sid(from); 2034 u32 tosid = task_sid(to); 2035 2036 return avc_has_perm(&selinux_state, 2037 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, 2038 NULL); 2039 } 2040 2041 static int selinux_binder_transfer_file(struct task_struct *from, 2042 struct task_struct *to, 2043 struct file *file) 2044 { 2045 u32 sid = task_sid(to); 2046 struct file_security_struct *fsec = selinux_file(file); 2047 struct dentry *dentry = file->f_path.dentry; 2048 struct inode_security_struct *isec; 2049 struct common_audit_data ad; 2050 int rc; 2051 2052 ad.type = LSM_AUDIT_DATA_PATH; 2053 ad.u.path = file->f_path; 2054 2055 if (sid != fsec->sid) { 2056 rc = avc_has_perm(&selinux_state, 2057 sid, fsec->sid, 2058 SECCLASS_FD, 2059 FD__USE, 2060 &ad); 2061 if (rc) 2062 return rc; 2063 } 2064 2065 #ifdef CONFIG_BPF_SYSCALL 2066 rc = bpf_fd_pass(file, sid); 2067 if (rc) 2068 return rc; 2069 #endif 2070 2071 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2072 return 0; 2073 2074 isec = backing_inode_security(dentry); 2075 return avc_has_perm(&selinux_state, 2076 sid, isec->sid, isec->sclass, file_to_av(file), 2077 &ad); 2078 } 2079 2080 static int selinux_ptrace_access_check(struct task_struct *child, 2081 unsigned int mode) 2082 { 2083 u32 sid = current_sid(); 2084 u32 csid = task_sid(child); 2085 2086 if (mode & PTRACE_MODE_READ) 2087 return avc_has_perm(&selinux_state, 2088 sid, csid, SECCLASS_FILE, FILE__READ, NULL); 2089 2090 return avc_has_perm(&selinux_state, 2091 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2092 } 2093 2094 static int selinux_ptrace_traceme(struct task_struct *parent) 2095 { 2096 return avc_has_perm(&selinux_state, 2097 task_sid(parent), current_sid(), SECCLASS_PROCESS, 2098 PROCESS__PTRACE, NULL); 2099 } 2100 2101 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 2102 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2103 { 2104 return avc_has_perm(&selinux_state, 2105 current_sid(), task_sid(target), SECCLASS_PROCESS, 2106 PROCESS__GETCAP, NULL); 2107 } 2108 2109 static int selinux_capset(struct cred *new, const struct cred *old, 2110 const kernel_cap_t *effective, 2111 const kernel_cap_t *inheritable, 2112 const kernel_cap_t *permitted) 2113 { 2114 return avc_has_perm(&selinux_state, 2115 cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2116 PROCESS__SETCAP, NULL); 2117 } 2118 2119 /* 2120 * (This comment used to live with the selinux_task_setuid hook, 2121 * which was removed). 2122 * 2123 * Since setuid only affects the current process, and since the SELinux 2124 * controls are not based on the Linux identity attributes, SELinux does not 2125 * need to control this operation. However, SELinux does control the use of 2126 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2127 */ 2128 2129 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2130 int cap, unsigned int opts) 2131 { 2132 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2133 } 2134 2135 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2136 { 2137 const struct cred *cred = current_cred(); 2138 int rc = 0; 2139 2140 if (!sb) 2141 return 0; 2142 2143 switch (cmds) { 2144 case Q_SYNC: 2145 case Q_QUOTAON: 2146 case Q_QUOTAOFF: 2147 case Q_SETINFO: 2148 case Q_SETQUOTA: 2149 case Q_XQUOTAOFF: 2150 case Q_XQUOTAON: 2151 case Q_XSETQLIM: 2152 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2153 break; 2154 case Q_GETFMT: 2155 case Q_GETINFO: 2156 case Q_GETQUOTA: 2157 case Q_XGETQUOTA: 2158 case Q_XGETQSTAT: 2159 case Q_XGETQSTATV: 2160 case Q_XGETNEXTQUOTA: 2161 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2162 break; 2163 default: 2164 rc = 0; /* let the kernel handle invalid cmds */ 2165 break; 2166 } 2167 return rc; 2168 } 2169 2170 static int selinux_quota_on(struct dentry *dentry) 2171 { 2172 const struct cred *cred = current_cred(); 2173 2174 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2175 } 2176 2177 static int selinux_syslog(int type) 2178 { 2179 switch (type) { 2180 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2181 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2182 return avc_has_perm(&selinux_state, 2183 current_sid(), SECINITSID_KERNEL, 2184 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2185 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2186 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2187 /* Set level of messages printed to console */ 2188 case SYSLOG_ACTION_CONSOLE_LEVEL: 2189 return avc_has_perm(&selinux_state, 2190 current_sid(), SECINITSID_KERNEL, 2191 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2192 NULL); 2193 } 2194 /* All other syslog types */ 2195 return avc_has_perm(&selinux_state, 2196 current_sid(), SECINITSID_KERNEL, 2197 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2198 } 2199 2200 /* 2201 * Check that a process has enough memory to allocate a new virtual 2202 * mapping. 0 means there is enough memory for the allocation to 2203 * succeed and -ENOMEM implies there is not. 2204 * 2205 * Do not audit the selinux permission check, as this is applied to all 2206 * processes that allocate mappings. 2207 */ 2208 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2209 { 2210 int rc, cap_sys_admin = 0; 2211 2212 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2213 CAP_OPT_NOAUDIT, true); 2214 if (rc == 0) 2215 cap_sys_admin = 1; 2216 2217 return cap_sys_admin; 2218 } 2219 2220 /* binprm security operations */ 2221 2222 static u32 ptrace_parent_sid(void) 2223 { 2224 u32 sid = 0; 2225 struct task_struct *tracer; 2226 2227 rcu_read_lock(); 2228 tracer = ptrace_parent(current); 2229 if (tracer) 2230 sid = task_sid(tracer); 2231 rcu_read_unlock(); 2232 2233 return sid; 2234 } 2235 2236 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2237 const struct task_security_struct *old_tsec, 2238 const struct task_security_struct *new_tsec) 2239 { 2240 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2241 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2242 int rc; 2243 u32 av; 2244 2245 if (!nnp && !nosuid) 2246 return 0; /* neither NNP nor nosuid */ 2247 2248 if (new_tsec->sid == old_tsec->sid) 2249 return 0; /* No change in credentials */ 2250 2251 /* 2252 * If the policy enables the nnp_nosuid_transition policy capability, 2253 * then we permit transitions under NNP or nosuid if the 2254 * policy allows the corresponding permission between 2255 * the old and new contexts. 2256 */ 2257 if (selinux_policycap_nnp_nosuid_transition()) { 2258 av = 0; 2259 if (nnp) 2260 av |= PROCESS2__NNP_TRANSITION; 2261 if (nosuid) 2262 av |= PROCESS2__NOSUID_TRANSITION; 2263 rc = avc_has_perm(&selinux_state, 2264 old_tsec->sid, new_tsec->sid, 2265 SECCLASS_PROCESS2, av, NULL); 2266 if (!rc) 2267 return 0; 2268 } 2269 2270 /* 2271 * We also permit NNP or nosuid transitions to bounded SIDs, 2272 * i.e. SIDs that are guaranteed to only be allowed a subset 2273 * of the permissions of the current SID. 2274 */ 2275 rc = security_bounded_transition(&selinux_state, old_tsec->sid, 2276 new_tsec->sid); 2277 if (!rc) 2278 return 0; 2279 2280 /* 2281 * On failure, preserve the errno values for NNP vs nosuid. 2282 * NNP: Operation not permitted for caller. 2283 * nosuid: Permission denied to file. 2284 */ 2285 if (nnp) 2286 return -EPERM; 2287 return -EACCES; 2288 } 2289 2290 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2291 { 2292 const struct task_security_struct *old_tsec; 2293 struct task_security_struct *new_tsec; 2294 struct inode_security_struct *isec; 2295 struct common_audit_data ad; 2296 struct inode *inode = file_inode(bprm->file); 2297 int rc; 2298 2299 /* SELinux context only depends on initial program or script and not 2300 * the script interpreter */ 2301 2302 old_tsec = selinux_cred(current_cred()); 2303 new_tsec = selinux_cred(bprm->cred); 2304 isec = inode_security(inode); 2305 2306 /* Default to the current task SID. */ 2307 new_tsec->sid = old_tsec->sid; 2308 new_tsec->osid = old_tsec->sid; 2309 2310 /* Reset fs, key, and sock SIDs on execve. */ 2311 new_tsec->create_sid = 0; 2312 new_tsec->keycreate_sid = 0; 2313 new_tsec->sockcreate_sid = 0; 2314 2315 if (old_tsec->exec_sid) { 2316 new_tsec->sid = old_tsec->exec_sid; 2317 /* Reset exec SID on execve. */ 2318 new_tsec->exec_sid = 0; 2319 2320 /* Fail on NNP or nosuid if not an allowed transition. */ 2321 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2322 if (rc) 2323 return rc; 2324 } else { 2325 /* Check for a default transition on this program. */ 2326 rc = security_transition_sid(&selinux_state, old_tsec->sid, 2327 isec->sid, SECCLASS_PROCESS, NULL, 2328 &new_tsec->sid); 2329 if (rc) 2330 return rc; 2331 2332 /* 2333 * Fallback to old SID on NNP or nosuid if not an allowed 2334 * transition. 2335 */ 2336 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2337 if (rc) 2338 new_tsec->sid = old_tsec->sid; 2339 } 2340 2341 ad.type = LSM_AUDIT_DATA_FILE; 2342 ad.u.file = bprm->file; 2343 2344 if (new_tsec->sid == old_tsec->sid) { 2345 rc = avc_has_perm(&selinux_state, 2346 old_tsec->sid, isec->sid, 2347 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2348 if (rc) 2349 return rc; 2350 } else { 2351 /* Check permissions for the transition. */ 2352 rc = avc_has_perm(&selinux_state, 2353 old_tsec->sid, new_tsec->sid, 2354 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2355 if (rc) 2356 return rc; 2357 2358 rc = avc_has_perm(&selinux_state, 2359 new_tsec->sid, isec->sid, 2360 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2361 if (rc) 2362 return rc; 2363 2364 /* Check for shared state */ 2365 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2366 rc = avc_has_perm(&selinux_state, 2367 old_tsec->sid, new_tsec->sid, 2368 SECCLASS_PROCESS, PROCESS__SHARE, 2369 NULL); 2370 if (rc) 2371 return -EPERM; 2372 } 2373 2374 /* Make sure that anyone attempting to ptrace over a task that 2375 * changes its SID has the appropriate permit */ 2376 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2377 u32 ptsid = ptrace_parent_sid(); 2378 if (ptsid != 0) { 2379 rc = avc_has_perm(&selinux_state, 2380 ptsid, new_tsec->sid, 2381 SECCLASS_PROCESS, 2382 PROCESS__PTRACE, NULL); 2383 if (rc) 2384 return -EPERM; 2385 } 2386 } 2387 2388 /* Clear any possibly unsafe personality bits on exec: */ 2389 bprm->per_clear |= PER_CLEAR_ON_SETID; 2390 2391 /* Enable secure mode for SIDs transitions unless 2392 the noatsecure permission is granted between 2393 the two SIDs, i.e. ahp returns 0. */ 2394 rc = avc_has_perm(&selinux_state, 2395 old_tsec->sid, new_tsec->sid, 2396 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2397 NULL); 2398 bprm->secureexec |= !!rc; 2399 } 2400 2401 return 0; 2402 } 2403 2404 static int match_file(const void *p, struct file *file, unsigned fd) 2405 { 2406 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2407 } 2408 2409 /* Derived from fs/exec.c:flush_old_files. */ 2410 static inline void flush_unauthorized_files(const struct cred *cred, 2411 struct files_struct *files) 2412 { 2413 struct file *file, *devnull = NULL; 2414 struct tty_struct *tty; 2415 int drop_tty = 0; 2416 unsigned n; 2417 2418 tty = get_current_tty(); 2419 if (tty) { 2420 spin_lock(&tty->files_lock); 2421 if (!list_empty(&tty->tty_files)) { 2422 struct tty_file_private *file_priv; 2423 2424 /* Revalidate access to controlling tty. 2425 Use file_path_has_perm on the tty path directly 2426 rather than using file_has_perm, as this particular 2427 open file may belong to another process and we are 2428 only interested in the inode-based check here. */ 2429 file_priv = list_first_entry(&tty->tty_files, 2430 struct tty_file_private, list); 2431 file = file_priv->file; 2432 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2433 drop_tty = 1; 2434 } 2435 spin_unlock(&tty->files_lock); 2436 tty_kref_put(tty); 2437 } 2438 /* Reset controlling tty. */ 2439 if (drop_tty) 2440 no_tty(); 2441 2442 /* Revalidate access to inherited open files. */ 2443 n = iterate_fd(files, 0, match_file, cred); 2444 if (!n) /* none found? */ 2445 return; 2446 2447 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2448 if (IS_ERR(devnull)) 2449 devnull = NULL; 2450 /* replace all the matching ones with this */ 2451 do { 2452 replace_fd(n - 1, devnull, 0); 2453 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2454 if (devnull) 2455 fput(devnull); 2456 } 2457 2458 /* 2459 * Prepare a process for imminent new credential changes due to exec 2460 */ 2461 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2462 { 2463 struct task_security_struct *new_tsec; 2464 struct rlimit *rlim, *initrlim; 2465 int rc, i; 2466 2467 new_tsec = selinux_cred(bprm->cred); 2468 if (new_tsec->sid == new_tsec->osid) 2469 return; 2470 2471 /* Close files for which the new task SID is not authorized. */ 2472 flush_unauthorized_files(bprm->cred, current->files); 2473 2474 /* Always clear parent death signal on SID transitions. */ 2475 current->pdeath_signal = 0; 2476 2477 /* Check whether the new SID can inherit resource limits from the old 2478 * SID. If not, reset all soft limits to the lower of the current 2479 * task's hard limit and the init task's soft limit. 2480 * 2481 * Note that the setting of hard limits (even to lower them) can be 2482 * controlled by the setrlimit check. The inclusion of the init task's 2483 * soft limit into the computation is to avoid resetting soft limits 2484 * higher than the default soft limit for cases where the default is 2485 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2486 */ 2487 rc = avc_has_perm(&selinux_state, 2488 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2489 PROCESS__RLIMITINH, NULL); 2490 if (rc) { 2491 /* protect against do_prlimit() */ 2492 task_lock(current); 2493 for (i = 0; i < RLIM_NLIMITS; i++) { 2494 rlim = current->signal->rlim + i; 2495 initrlim = init_task.signal->rlim + i; 2496 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2497 } 2498 task_unlock(current); 2499 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2500 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2501 } 2502 } 2503 2504 /* 2505 * Clean up the process immediately after the installation of new credentials 2506 * due to exec 2507 */ 2508 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2509 { 2510 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2511 u32 osid, sid; 2512 int rc; 2513 2514 osid = tsec->osid; 2515 sid = tsec->sid; 2516 2517 if (sid == osid) 2518 return; 2519 2520 /* Check whether the new SID can inherit signal state from the old SID. 2521 * If not, clear itimers to avoid subsequent signal generation and 2522 * flush and unblock signals. 2523 * 2524 * This must occur _after_ the task SID has been updated so that any 2525 * kill done after the flush will be checked against the new SID. 2526 */ 2527 rc = avc_has_perm(&selinux_state, 2528 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2529 if (rc) { 2530 clear_itimer(); 2531 2532 spin_lock_irq(¤t->sighand->siglock); 2533 if (!fatal_signal_pending(current)) { 2534 flush_sigqueue(¤t->pending); 2535 flush_sigqueue(¤t->signal->shared_pending); 2536 flush_signal_handlers(current, 1); 2537 sigemptyset(¤t->blocked); 2538 recalc_sigpending(); 2539 } 2540 spin_unlock_irq(¤t->sighand->siglock); 2541 } 2542 2543 /* Wake up the parent if it is waiting so that it can recheck 2544 * wait permission to the new task SID. */ 2545 read_lock(&tasklist_lock); 2546 __wake_up_parent(current, current->real_parent); 2547 read_unlock(&tasklist_lock); 2548 } 2549 2550 /* superblock security operations */ 2551 2552 static int selinux_sb_alloc_security(struct super_block *sb) 2553 { 2554 struct superblock_security_struct *sbsec; 2555 2556 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 2557 if (!sbsec) 2558 return -ENOMEM; 2559 2560 mutex_init(&sbsec->lock); 2561 INIT_LIST_HEAD(&sbsec->isec_head); 2562 spin_lock_init(&sbsec->isec_lock); 2563 sbsec->sb = sb; 2564 sbsec->sid = SECINITSID_UNLABELED; 2565 sbsec->def_sid = SECINITSID_FILE; 2566 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2567 sb->s_security = sbsec; 2568 2569 return 0; 2570 } 2571 2572 static void selinux_sb_free_security(struct super_block *sb) 2573 { 2574 superblock_free_security(sb); 2575 } 2576 2577 static inline int opt_len(const char *s) 2578 { 2579 bool open_quote = false; 2580 int len; 2581 char c; 2582 2583 for (len = 0; (c = s[len]) != '\0'; len++) { 2584 if (c == '"') 2585 open_quote = !open_quote; 2586 if (c == ',' && !open_quote) 2587 break; 2588 } 2589 return len; 2590 } 2591 2592 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2593 { 2594 char *from = options; 2595 char *to = options; 2596 bool first = true; 2597 int rc; 2598 2599 while (1) { 2600 int len = opt_len(from); 2601 int token; 2602 char *arg = NULL; 2603 2604 token = match_opt_prefix(from, len, &arg); 2605 2606 if (token != Opt_error) { 2607 char *p, *q; 2608 2609 /* strip quotes */ 2610 if (arg) { 2611 for (p = q = arg; p < from + len; p++) { 2612 char c = *p; 2613 if (c != '"') 2614 *q++ = c; 2615 } 2616 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2617 if (!arg) { 2618 rc = -ENOMEM; 2619 goto free_opt; 2620 } 2621 } 2622 rc = selinux_add_opt(token, arg, mnt_opts); 2623 if (unlikely(rc)) { 2624 kfree(arg); 2625 goto free_opt; 2626 } 2627 } else { 2628 if (!first) { // copy with preceding comma 2629 from--; 2630 len++; 2631 } 2632 if (to != from) 2633 memmove(to, from, len); 2634 to += len; 2635 first = false; 2636 } 2637 if (!from[len]) 2638 break; 2639 from += len + 1; 2640 } 2641 *to = '\0'; 2642 return 0; 2643 2644 free_opt: 2645 if (*mnt_opts) { 2646 selinux_free_mnt_opts(*mnt_opts); 2647 *mnt_opts = NULL; 2648 } 2649 return rc; 2650 } 2651 2652 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2653 { 2654 struct selinux_mnt_opts *opts = mnt_opts; 2655 struct superblock_security_struct *sbsec = sb->s_security; 2656 u32 sid; 2657 int rc; 2658 2659 if (!(sbsec->flags & SE_SBINITIALIZED)) 2660 return 0; 2661 2662 if (!opts) 2663 return 0; 2664 2665 if (opts->fscontext) { 2666 rc = parse_sid(sb, opts->fscontext, &sid); 2667 if (rc) 2668 return rc; 2669 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2670 goto out_bad_option; 2671 } 2672 if (opts->context) { 2673 rc = parse_sid(sb, opts->context, &sid); 2674 if (rc) 2675 return rc; 2676 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2677 goto out_bad_option; 2678 } 2679 if (opts->rootcontext) { 2680 struct inode_security_struct *root_isec; 2681 root_isec = backing_inode_security(sb->s_root); 2682 rc = parse_sid(sb, opts->rootcontext, &sid); 2683 if (rc) 2684 return rc; 2685 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2686 goto out_bad_option; 2687 } 2688 if (opts->defcontext) { 2689 rc = parse_sid(sb, opts->defcontext, &sid); 2690 if (rc) 2691 return rc; 2692 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2693 goto out_bad_option; 2694 } 2695 return 0; 2696 2697 out_bad_option: 2698 pr_warn("SELinux: unable to change security options " 2699 "during remount (dev %s, type=%s)\n", sb->s_id, 2700 sb->s_type->name); 2701 return -EINVAL; 2702 } 2703 2704 static int selinux_sb_kern_mount(struct super_block *sb) 2705 { 2706 const struct cred *cred = current_cred(); 2707 struct common_audit_data ad; 2708 2709 ad.type = LSM_AUDIT_DATA_DENTRY; 2710 ad.u.dentry = sb->s_root; 2711 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2712 } 2713 2714 static int selinux_sb_statfs(struct dentry *dentry) 2715 { 2716 const struct cred *cred = current_cred(); 2717 struct common_audit_data ad; 2718 2719 ad.type = LSM_AUDIT_DATA_DENTRY; 2720 ad.u.dentry = dentry->d_sb->s_root; 2721 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2722 } 2723 2724 static int selinux_mount(const char *dev_name, 2725 const struct path *path, 2726 const char *type, 2727 unsigned long flags, 2728 void *data) 2729 { 2730 const struct cred *cred = current_cred(); 2731 2732 if (flags & MS_REMOUNT) 2733 return superblock_has_perm(cred, path->dentry->d_sb, 2734 FILESYSTEM__REMOUNT, NULL); 2735 else 2736 return path_has_perm(cred, path, FILE__MOUNTON); 2737 } 2738 2739 static int selinux_move_mount(const struct path *from_path, 2740 const struct path *to_path) 2741 { 2742 const struct cred *cred = current_cred(); 2743 2744 return path_has_perm(cred, to_path, FILE__MOUNTON); 2745 } 2746 2747 static int selinux_umount(struct vfsmount *mnt, int flags) 2748 { 2749 const struct cred *cred = current_cred(); 2750 2751 return superblock_has_perm(cred, mnt->mnt_sb, 2752 FILESYSTEM__UNMOUNT, NULL); 2753 } 2754 2755 static int selinux_fs_context_dup(struct fs_context *fc, 2756 struct fs_context *src_fc) 2757 { 2758 const struct selinux_mnt_opts *src = src_fc->security; 2759 struct selinux_mnt_opts *opts; 2760 2761 if (!src) 2762 return 0; 2763 2764 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 2765 if (!fc->security) 2766 return -ENOMEM; 2767 2768 opts = fc->security; 2769 2770 if (src->fscontext) { 2771 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); 2772 if (!opts->fscontext) 2773 return -ENOMEM; 2774 } 2775 if (src->context) { 2776 opts->context = kstrdup(src->context, GFP_KERNEL); 2777 if (!opts->context) 2778 return -ENOMEM; 2779 } 2780 if (src->rootcontext) { 2781 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); 2782 if (!opts->rootcontext) 2783 return -ENOMEM; 2784 } 2785 if (src->defcontext) { 2786 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); 2787 if (!opts->defcontext) 2788 return -ENOMEM; 2789 } 2790 return 0; 2791 } 2792 2793 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2794 fsparam_string(CONTEXT_STR, Opt_context), 2795 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2796 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2797 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2798 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2799 {} 2800 }; 2801 2802 static int selinux_fs_context_parse_param(struct fs_context *fc, 2803 struct fs_parameter *param) 2804 { 2805 struct fs_parse_result result; 2806 int opt, rc; 2807 2808 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2809 if (opt < 0) 2810 return opt; 2811 2812 rc = selinux_add_opt(opt, param->string, &fc->security); 2813 if (!rc) { 2814 param->string = NULL; 2815 rc = 1; 2816 } 2817 return rc; 2818 } 2819 2820 /* inode security operations */ 2821 2822 static int selinux_inode_alloc_security(struct inode *inode) 2823 { 2824 struct inode_security_struct *isec = selinux_inode(inode); 2825 u32 sid = current_sid(); 2826 2827 spin_lock_init(&isec->lock); 2828 INIT_LIST_HEAD(&isec->list); 2829 isec->inode = inode; 2830 isec->sid = SECINITSID_UNLABELED; 2831 isec->sclass = SECCLASS_FILE; 2832 isec->task_sid = sid; 2833 isec->initialized = LABEL_INVALID; 2834 2835 return 0; 2836 } 2837 2838 static void selinux_inode_free_security(struct inode *inode) 2839 { 2840 inode_free_security(inode); 2841 } 2842 2843 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2844 const struct qstr *name, void **ctx, 2845 u32 *ctxlen) 2846 { 2847 u32 newsid; 2848 int rc; 2849 2850 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2851 d_inode(dentry->d_parent), name, 2852 inode_mode_to_security_class(mode), 2853 &newsid); 2854 if (rc) 2855 return rc; 2856 2857 return security_sid_to_context(&selinux_state, newsid, (char **)ctx, 2858 ctxlen); 2859 } 2860 2861 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2862 struct qstr *name, 2863 const struct cred *old, 2864 struct cred *new) 2865 { 2866 u32 newsid; 2867 int rc; 2868 struct task_security_struct *tsec; 2869 2870 rc = selinux_determine_inode_label(selinux_cred(old), 2871 d_inode(dentry->d_parent), name, 2872 inode_mode_to_security_class(mode), 2873 &newsid); 2874 if (rc) 2875 return rc; 2876 2877 tsec = selinux_cred(new); 2878 tsec->create_sid = newsid; 2879 return 0; 2880 } 2881 2882 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2883 const struct qstr *qstr, 2884 const char **name, 2885 void **value, size_t *len) 2886 { 2887 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2888 struct superblock_security_struct *sbsec; 2889 u32 newsid, clen; 2890 int rc; 2891 char *context; 2892 2893 sbsec = dir->i_sb->s_security; 2894 2895 newsid = tsec->create_sid; 2896 2897 rc = selinux_determine_inode_label(tsec, dir, qstr, 2898 inode_mode_to_security_class(inode->i_mode), 2899 &newsid); 2900 if (rc) 2901 return rc; 2902 2903 /* Possibly defer initialization to selinux_complete_init. */ 2904 if (sbsec->flags & SE_SBINITIALIZED) { 2905 struct inode_security_struct *isec = selinux_inode(inode); 2906 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2907 isec->sid = newsid; 2908 isec->initialized = LABEL_INITIALIZED; 2909 } 2910 2911 if (!selinux_initialized(&selinux_state) || 2912 !(sbsec->flags & SBLABEL_MNT)) 2913 return -EOPNOTSUPP; 2914 2915 if (name) 2916 *name = XATTR_SELINUX_SUFFIX; 2917 2918 if (value && len) { 2919 rc = security_sid_to_context_force(&selinux_state, newsid, 2920 &context, &clen); 2921 if (rc) 2922 return rc; 2923 *value = context; 2924 *len = clen; 2925 } 2926 2927 return 0; 2928 } 2929 2930 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 2931 { 2932 return may_create(dir, dentry, SECCLASS_FILE); 2933 } 2934 2935 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2936 { 2937 return may_link(dir, old_dentry, MAY_LINK); 2938 } 2939 2940 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2941 { 2942 return may_link(dir, dentry, MAY_UNLINK); 2943 } 2944 2945 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2946 { 2947 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2948 } 2949 2950 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 2951 { 2952 return may_create(dir, dentry, SECCLASS_DIR); 2953 } 2954 2955 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2956 { 2957 return may_link(dir, dentry, MAY_RMDIR); 2958 } 2959 2960 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 2961 { 2962 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2963 } 2964 2965 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2966 struct inode *new_inode, struct dentry *new_dentry) 2967 { 2968 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2969 } 2970 2971 static int selinux_inode_readlink(struct dentry *dentry) 2972 { 2973 const struct cred *cred = current_cred(); 2974 2975 return dentry_has_perm(cred, dentry, FILE__READ); 2976 } 2977 2978 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 2979 bool rcu) 2980 { 2981 const struct cred *cred = current_cred(); 2982 struct common_audit_data ad; 2983 struct inode_security_struct *isec; 2984 u32 sid; 2985 2986 validate_creds(cred); 2987 2988 ad.type = LSM_AUDIT_DATA_DENTRY; 2989 ad.u.dentry = dentry; 2990 sid = cred_sid(cred); 2991 isec = inode_security_rcu(inode, rcu); 2992 if (IS_ERR(isec)) 2993 return PTR_ERR(isec); 2994 2995 return avc_has_perm_flags(&selinux_state, 2996 sid, isec->sid, isec->sclass, FILE__READ, &ad, 2997 rcu ? MAY_NOT_BLOCK : 0); 2998 } 2999 3000 static noinline int audit_inode_permission(struct inode *inode, 3001 u32 perms, u32 audited, u32 denied, 3002 int result) 3003 { 3004 struct common_audit_data ad; 3005 struct inode_security_struct *isec = selinux_inode(inode); 3006 int rc; 3007 3008 ad.type = LSM_AUDIT_DATA_INODE; 3009 ad.u.inode = inode; 3010 3011 rc = slow_avc_audit(&selinux_state, 3012 current_sid(), isec->sid, isec->sclass, perms, 3013 audited, denied, result, &ad); 3014 if (rc) 3015 return rc; 3016 return 0; 3017 } 3018 3019 static int selinux_inode_permission(struct inode *inode, int mask) 3020 { 3021 const struct cred *cred = current_cred(); 3022 u32 perms; 3023 bool from_access; 3024 bool no_block = mask & MAY_NOT_BLOCK; 3025 struct inode_security_struct *isec; 3026 u32 sid; 3027 struct av_decision avd; 3028 int rc, rc2; 3029 u32 audited, denied; 3030 3031 from_access = mask & MAY_ACCESS; 3032 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3033 3034 /* No permission to check. Existence test. */ 3035 if (!mask) 3036 return 0; 3037 3038 validate_creds(cred); 3039 3040 if (unlikely(IS_PRIVATE(inode))) 3041 return 0; 3042 3043 perms = file_mask_to_av(inode->i_mode, mask); 3044 3045 sid = cred_sid(cred); 3046 isec = inode_security_rcu(inode, no_block); 3047 if (IS_ERR(isec)) 3048 return PTR_ERR(isec); 3049 3050 rc = avc_has_perm_noaudit(&selinux_state, 3051 sid, isec->sid, isec->sclass, perms, 3052 no_block ? AVC_NONBLOCKING : 0, 3053 &avd); 3054 audited = avc_audit_required(perms, &avd, rc, 3055 from_access ? FILE__AUDIT_ACCESS : 0, 3056 &denied); 3057 if (likely(!audited)) 3058 return rc; 3059 3060 /* fall back to ref-walk if we have to generate audit */ 3061 if (no_block) 3062 return -ECHILD; 3063 3064 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3065 if (rc2) 3066 return rc2; 3067 return rc; 3068 } 3069 3070 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3071 { 3072 const struct cred *cred = current_cred(); 3073 struct inode *inode = d_backing_inode(dentry); 3074 unsigned int ia_valid = iattr->ia_valid; 3075 __u32 av = FILE__WRITE; 3076 3077 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3078 if (ia_valid & ATTR_FORCE) { 3079 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3080 ATTR_FORCE); 3081 if (!ia_valid) 3082 return 0; 3083 } 3084 3085 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3086 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3087 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3088 3089 if (selinux_policycap_openperm() && 3090 inode->i_sb->s_magic != SOCKFS_MAGIC && 3091 (ia_valid & ATTR_SIZE) && 3092 !(ia_valid & ATTR_FILE)) 3093 av |= FILE__OPEN; 3094 3095 return dentry_has_perm(cred, dentry, av); 3096 } 3097 3098 static int selinux_inode_getattr(const struct path *path) 3099 { 3100 return path_has_perm(current_cred(), path, FILE__GETATTR); 3101 } 3102 3103 static bool has_cap_mac_admin(bool audit) 3104 { 3105 const struct cred *cred = current_cred(); 3106 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3107 3108 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3109 return false; 3110 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3111 return false; 3112 return true; 3113 } 3114 3115 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 3116 const void *value, size_t size, int flags) 3117 { 3118 struct inode *inode = d_backing_inode(dentry); 3119 struct inode_security_struct *isec; 3120 struct superblock_security_struct *sbsec; 3121 struct common_audit_data ad; 3122 u32 newsid, sid = current_sid(); 3123 int rc = 0; 3124 3125 if (strcmp(name, XATTR_NAME_SELINUX)) { 3126 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3127 if (rc) 3128 return rc; 3129 3130 /* Not an attribute we recognize, so just check the 3131 ordinary setattr permission. */ 3132 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3133 } 3134 3135 if (!selinux_initialized(&selinux_state)) 3136 return (inode_owner_or_capable(inode) ? 0 : -EPERM); 3137 3138 sbsec = inode->i_sb->s_security; 3139 if (!(sbsec->flags & SBLABEL_MNT)) 3140 return -EOPNOTSUPP; 3141 3142 if (!inode_owner_or_capable(inode)) 3143 return -EPERM; 3144 3145 ad.type = LSM_AUDIT_DATA_DENTRY; 3146 ad.u.dentry = dentry; 3147 3148 isec = backing_inode_security(dentry); 3149 rc = avc_has_perm(&selinux_state, 3150 sid, isec->sid, isec->sclass, 3151 FILE__RELABELFROM, &ad); 3152 if (rc) 3153 return rc; 3154 3155 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3156 GFP_KERNEL); 3157 if (rc == -EINVAL) { 3158 if (!has_cap_mac_admin(true)) { 3159 struct audit_buffer *ab; 3160 size_t audit_size; 3161 3162 /* We strip a nul only if it is at the end, otherwise the 3163 * context contains a nul and we should audit that */ 3164 if (value) { 3165 const char *str = value; 3166 3167 if (str[size - 1] == '\0') 3168 audit_size = size - 1; 3169 else 3170 audit_size = size; 3171 } else { 3172 audit_size = 0; 3173 } 3174 ab = audit_log_start(audit_context(), 3175 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3176 audit_log_format(ab, "op=setxattr invalid_context="); 3177 audit_log_n_untrustedstring(ab, value, audit_size); 3178 audit_log_end(ab); 3179 3180 return rc; 3181 } 3182 rc = security_context_to_sid_force(&selinux_state, value, 3183 size, &newsid); 3184 } 3185 if (rc) 3186 return rc; 3187 3188 rc = avc_has_perm(&selinux_state, 3189 sid, newsid, isec->sclass, 3190 FILE__RELABELTO, &ad); 3191 if (rc) 3192 return rc; 3193 3194 rc = security_validate_transition(&selinux_state, isec->sid, newsid, 3195 sid, isec->sclass); 3196 if (rc) 3197 return rc; 3198 3199 return avc_has_perm(&selinux_state, 3200 newsid, 3201 sbsec->sid, 3202 SECCLASS_FILESYSTEM, 3203 FILESYSTEM__ASSOCIATE, 3204 &ad); 3205 } 3206 3207 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3208 const void *value, size_t size, 3209 int flags) 3210 { 3211 struct inode *inode = d_backing_inode(dentry); 3212 struct inode_security_struct *isec; 3213 u32 newsid; 3214 int rc; 3215 3216 if (strcmp(name, XATTR_NAME_SELINUX)) { 3217 /* Not an attribute we recognize, so nothing to do. */ 3218 return; 3219 } 3220 3221 if (!selinux_initialized(&selinux_state)) { 3222 /* If we haven't even been initialized, then we can't validate 3223 * against a policy, so leave the label as invalid. It may 3224 * resolve to a valid label on the next revalidation try if 3225 * we've since initialized. 3226 */ 3227 return; 3228 } 3229 3230 rc = security_context_to_sid_force(&selinux_state, value, size, 3231 &newsid); 3232 if (rc) { 3233 pr_err("SELinux: unable to map context to SID" 3234 "for (%s, %lu), rc=%d\n", 3235 inode->i_sb->s_id, inode->i_ino, -rc); 3236 return; 3237 } 3238 3239 isec = backing_inode_security(dentry); 3240 spin_lock(&isec->lock); 3241 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3242 isec->sid = newsid; 3243 isec->initialized = LABEL_INITIALIZED; 3244 spin_unlock(&isec->lock); 3245 3246 return; 3247 } 3248 3249 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3250 { 3251 const struct cred *cred = current_cred(); 3252 3253 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3254 } 3255 3256 static int selinux_inode_listxattr(struct dentry *dentry) 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_removexattr(struct dentry *dentry, const char *name) 3264 { 3265 if (strcmp(name, XATTR_NAME_SELINUX)) { 3266 int rc = cap_inode_removexattr(dentry, name); 3267 if (rc) 3268 return rc; 3269 3270 /* Not an attribute we recognize, so just check the 3271 ordinary setattr permission. */ 3272 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3273 } 3274 3275 if (!selinux_initialized(&selinux_state)) 3276 return 0; 3277 3278 /* No one is allowed to remove a SELinux security label. 3279 You can change the label, but all data must be labeled. */ 3280 return -EACCES; 3281 } 3282 3283 static int selinux_path_notify(const struct path *path, u64 mask, 3284 unsigned int obj_type) 3285 { 3286 int ret; 3287 u32 perm; 3288 3289 struct common_audit_data ad; 3290 3291 ad.type = LSM_AUDIT_DATA_PATH; 3292 ad.u.path = *path; 3293 3294 /* 3295 * Set permission needed based on the type of mark being set. 3296 * Performs an additional check for sb watches. 3297 */ 3298 switch (obj_type) { 3299 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3300 perm = FILE__WATCH_MOUNT; 3301 break; 3302 case FSNOTIFY_OBJ_TYPE_SB: 3303 perm = FILE__WATCH_SB; 3304 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3305 FILESYSTEM__WATCH, &ad); 3306 if (ret) 3307 return ret; 3308 break; 3309 case FSNOTIFY_OBJ_TYPE_INODE: 3310 perm = FILE__WATCH; 3311 break; 3312 default: 3313 return -EINVAL; 3314 } 3315 3316 /* blocking watches require the file:watch_with_perm permission */ 3317 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3318 perm |= FILE__WATCH_WITH_PERM; 3319 3320 /* watches on read-like events need the file:watch_reads permission */ 3321 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3322 perm |= FILE__WATCH_READS; 3323 3324 return path_has_perm(current_cred(), path, perm); 3325 } 3326 3327 /* 3328 * Copy the inode security context value to the user. 3329 * 3330 * Permission check is handled by selinux_inode_getxattr hook. 3331 */ 3332 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) 3333 { 3334 u32 size; 3335 int error; 3336 char *context = NULL; 3337 struct inode_security_struct *isec; 3338 3339 /* 3340 * If we're not initialized yet, then we can't validate contexts, so 3341 * just let vfs_getxattr fall back to using the on-disk xattr. 3342 */ 3343 if (!selinux_initialized(&selinux_state) || 3344 strcmp(name, XATTR_SELINUX_SUFFIX)) 3345 return -EOPNOTSUPP; 3346 3347 /* 3348 * If the caller has CAP_MAC_ADMIN, then get the raw context 3349 * value even if it is not defined by current policy; otherwise, 3350 * use the in-core value under current policy. 3351 * Use the non-auditing forms of the permission checks since 3352 * getxattr may be called by unprivileged processes commonly 3353 * and lack of permission just means that we fall back to the 3354 * in-core context value, not a denial. 3355 */ 3356 isec = inode_security(inode); 3357 if (has_cap_mac_admin(false)) 3358 error = security_sid_to_context_force(&selinux_state, 3359 isec->sid, &context, 3360 &size); 3361 else 3362 error = security_sid_to_context(&selinux_state, isec->sid, 3363 &context, &size); 3364 if (error) 3365 return error; 3366 error = size; 3367 if (alloc) { 3368 *buffer = context; 3369 goto out_nofree; 3370 } 3371 kfree(context); 3372 out_nofree: 3373 return error; 3374 } 3375 3376 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3377 const void *value, size_t size, int flags) 3378 { 3379 struct inode_security_struct *isec = inode_security_novalidate(inode); 3380 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 3381 u32 newsid; 3382 int rc; 3383 3384 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3385 return -EOPNOTSUPP; 3386 3387 if (!(sbsec->flags & SBLABEL_MNT)) 3388 return -EOPNOTSUPP; 3389 3390 if (!value || !size) 3391 return -EACCES; 3392 3393 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3394 GFP_KERNEL); 3395 if (rc) 3396 return rc; 3397 3398 spin_lock(&isec->lock); 3399 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3400 isec->sid = newsid; 3401 isec->initialized = LABEL_INITIALIZED; 3402 spin_unlock(&isec->lock); 3403 return 0; 3404 } 3405 3406 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3407 { 3408 const int len = sizeof(XATTR_NAME_SELINUX); 3409 if (buffer && len <= buffer_size) 3410 memcpy(buffer, XATTR_NAME_SELINUX, len); 3411 return len; 3412 } 3413 3414 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3415 { 3416 struct inode_security_struct *isec = inode_security_novalidate(inode); 3417 *secid = isec->sid; 3418 } 3419 3420 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3421 { 3422 u32 sid; 3423 struct task_security_struct *tsec; 3424 struct cred *new_creds = *new; 3425 3426 if (new_creds == NULL) { 3427 new_creds = prepare_creds(); 3428 if (!new_creds) 3429 return -ENOMEM; 3430 } 3431 3432 tsec = selinux_cred(new_creds); 3433 /* Get label from overlay inode and set it in create_sid */ 3434 selinux_inode_getsecid(d_inode(src), &sid); 3435 tsec->create_sid = sid; 3436 *new = new_creds; 3437 return 0; 3438 } 3439 3440 static int selinux_inode_copy_up_xattr(const char *name) 3441 { 3442 /* The copy_up hook above sets the initial context on an inode, but we 3443 * don't then want to overwrite it by blindly copying all the lower 3444 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3445 */ 3446 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3447 return 1; /* Discard */ 3448 /* 3449 * Any other attribute apart from SELINUX is not claimed, supported 3450 * by selinux. 3451 */ 3452 return -EOPNOTSUPP; 3453 } 3454 3455 /* kernfs node operations */ 3456 3457 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3458 struct kernfs_node *kn) 3459 { 3460 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3461 u32 parent_sid, newsid, clen; 3462 int rc; 3463 char *context; 3464 3465 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3466 if (rc == -ENODATA) 3467 return 0; 3468 else if (rc < 0) 3469 return rc; 3470 3471 clen = (u32)rc; 3472 context = kmalloc(clen, GFP_KERNEL); 3473 if (!context) 3474 return -ENOMEM; 3475 3476 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3477 if (rc < 0) { 3478 kfree(context); 3479 return rc; 3480 } 3481 3482 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, 3483 GFP_KERNEL); 3484 kfree(context); 3485 if (rc) 3486 return rc; 3487 3488 if (tsec->create_sid) { 3489 newsid = tsec->create_sid; 3490 } else { 3491 u16 secclass = inode_mode_to_security_class(kn->mode); 3492 struct qstr q; 3493 3494 q.name = kn->name; 3495 q.hash_len = hashlen_string(kn_dir, kn->name); 3496 3497 rc = security_transition_sid(&selinux_state, tsec->sid, 3498 parent_sid, secclass, &q, 3499 &newsid); 3500 if (rc) 3501 return rc; 3502 } 3503 3504 rc = security_sid_to_context_force(&selinux_state, newsid, 3505 &context, &clen); 3506 if (rc) 3507 return rc; 3508 3509 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3510 XATTR_CREATE); 3511 kfree(context); 3512 return rc; 3513 } 3514 3515 3516 /* file security operations */ 3517 3518 static int selinux_revalidate_file_permission(struct file *file, int mask) 3519 { 3520 const struct cred *cred = current_cred(); 3521 struct inode *inode = file_inode(file); 3522 3523 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3524 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3525 mask |= MAY_APPEND; 3526 3527 return file_has_perm(cred, file, 3528 file_mask_to_av(inode->i_mode, mask)); 3529 } 3530 3531 static int selinux_file_permission(struct file *file, int mask) 3532 { 3533 struct inode *inode = file_inode(file); 3534 struct file_security_struct *fsec = selinux_file(file); 3535 struct inode_security_struct *isec; 3536 u32 sid = current_sid(); 3537 3538 if (!mask) 3539 /* No permission to check. Existence test. */ 3540 return 0; 3541 3542 isec = inode_security(inode); 3543 if (sid == fsec->sid && fsec->isid == isec->sid && 3544 fsec->pseqno == avc_policy_seqno(&selinux_state)) 3545 /* No change since file_open check. */ 3546 return 0; 3547 3548 return selinux_revalidate_file_permission(file, mask); 3549 } 3550 3551 static int selinux_file_alloc_security(struct file *file) 3552 { 3553 struct file_security_struct *fsec = selinux_file(file); 3554 u32 sid = current_sid(); 3555 3556 fsec->sid = sid; 3557 fsec->fown_sid = sid; 3558 3559 return 0; 3560 } 3561 3562 /* 3563 * Check whether a task has the ioctl permission and cmd 3564 * operation to an inode. 3565 */ 3566 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3567 u32 requested, u16 cmd) 3568 { 3569 struct common_audit_data ad; 3570 struct file_security_struct *fsec = selinux_file(file); 3571 struct inode *inode = file_inode(file); 3572 struct inode_security_struct *isec; 3573 struct lsm_ioctlop_audit ioctl; 3574 u32 ssid = cred_sid(cred); 3575 int rc; 3576 u8 driver = cmd >> 8; 3577 u8 xperm = cmd & 0xff; 3578 3579 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3580 ad.u.op = &ioctl; 3581 ad.u.op->cmd = cmd; 3582 ad.u.op->path = file->f_path; 3583 3584 if (ssid != fsec->sid) { 3585 rc = avc_has_perm(&selinux_state, 3586 ssid, fsec->sid, 3587 SECCLASS_FD, 3588 FD__USE, 3589 &ad); 3590 if (rc) 3591 goto out; 3592 } 3593 3594 if (unlikely(IS_PRIVATE(inode))) 3595 return 0; 3596 3597 isec = inode_security(inode); 3598 rc = avc_has_extended_perms(&selinux_state, 3599 ssid, isec->sid, isec->sclass, 3600 requested, driver, xperm, &ad); 3601 out: 3602 return rc; 3603 } 3604 3605 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3606 unsigned long arg) 3607 { 3608 const struct cred *cred = current_cred(); 3609 int error = 0; 3610 3611 switch (cmd) { 3612 case FIONREAD: 3613 case FIBMAP: 3614 case FIGETBSZ: 3615 case FS_IOC_GETFLAGS: 3616 case FS_IOC_GETVERSION: 3617 error = file_has_perm(cred, file, FILE__GETATTR); 3618 break; 3619 3620 case FS_IOC_SETFLAGS: 3621 case FS_IOC_SETVERSION: 3622 error = file_has_perm(cred, file, FILE__SETATTR); 3623 break; 3624 3625 /* sys_ioctl() checks */ 3626 case FIONBIO: 3627 case FIOASYNC: 3628 error = file_has_perm(cred, file, 0); 3629 break; 3630 3631 case KDSKBENT: 3632 case KDSKBSENT: 3633 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3634 CAP_OPT_NONE, true); 3635 break; 3636 3637 /* default case assumes that the command will go 3638 * to the file's ioctl() function. 3639 */ 3640 default: 3641 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3642 } 3643 return error; 3644 } 3645 3646 static int default_noexec __ro_after_init; 3647 3648 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3649 { 3650 const struct cred *cred = current_cred(); 3651 u32 sid = cred_sid(cred); 3652 int rc = 0; 3653 3654 if (default_noexec && 3655 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3656 (!shared && (prot & PROT_WRITE)))) { 3657 /* 3658 * We are making executable an anonymous mapping or a 3659 * private file mapping that will also be writable. 3660 * This has an additional check. 3661 */ 3662 rc = avc_has_perm(&selinux_state, 3663 sid, sid, SECCLASS_PROCESS, 3664 PROCESS__EXECMEM, NULL); 3665 if (rc) 3666 goto error; 3667 } 3668 3669 if (file) { 3670 /* read access is always possible with a mapping */ 3671 u32 av = FILE__READ; 3672 3673 /* write access only matters if the mapping is shared */ 3674 if (shared && (prot & PROT_WRITE)) 3675 av |= FILE__WRITE; 3676 3677 if (prot & PROT_EXEC) 3678 av |= FILE__EXECUTE; 3679 3680 return file_has_perm(cred, file, av); 3681 } 3682 3683 error: 3684 return rc; 3685 } 3686 3687 static int selinux_mmap_addr(unsigned long addr) 3688 { 3689 int rc = 0; 3690 3691 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3692 u32 sid = current_sid(); 3693 rc = avc_has_perm(&selinux_state, 3694 sid, sid, SECCLASS_MEMPROTECT, 3695 MEMPROTECT__MMAP_ZERO, NULL); 3696 } 3697 3698 return rc; 3699 } 3700 3701 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3702 unsigned long prot, unsigned long flags) 3703 { 3704 struct common_audit_data ad; 3705 int rc; 3706 3707 if (file) { 3708 ad.type = LSM_AUDIT_DATA_FILE; 3709 ad.u.file = file; 3710 rc = inode_has_perm(current_cred(), file_inode(file), 3711 FILE__MAP, &ad); 3712 if (rc) 3713 return rc; 3714 } 3715 3716 if (checkreqprot_get(&selinux_state)) 3717 prot = reqprot; 3718 3719 return file_map_prot_check(file, prot, 3720 (flags & MAP_TYPE) == MAP_SHARED); 3721 } 3722 3723 static int selinux_file_mprotect(struct vm_area_struct *vma, 3724 unsigned long reqprot, 3725 unsigned long prot) 3726 { 3727 const struct cred *cred = current_cred(); 3728 u32 sid = cred_sid(cred); 3729 3730 if (checkreqprot_get(&selinux_state)) 3731 prot = reqprot; 3732 3733 if (default_noexec && 3734 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3735 int rc = 0; 3736 if (vma->vm_start >= vma->vm_mm->start_brk && 3737 vma->vm_end <= vma->vm_mm->brk) { 3738 rc = avc_has_perm(&selinux_state, 3739 sid, sid, SECCLASS_PROCESS, 3740 PROCESS__EXECHEAP, NULL); 3741 } else if (!vma->vm_file && 3742 ((vma->vm_start <= vma->vm_mm->start_stack && 3743 vma->vm_end >= vma->vm_mm->start_stack) || 3744 vma_is_stack_for_current(vma))) { 3745 rc = avc_has_perm(&selinux_state, 3746 sid, sid, SECCLASS_PROCESS, 3747 PROCESS__EXECSTACK, NULL); 3748 } else if (vma->vm_file && vma->anon_vma) { 3749 /* 3750 * We are making executable a file mapping that has 3751 * had some COW done. Since pages might have been 3752 * written, check ability to execute the possibly 3753 * modified content. This typically should only 3754 * occur for text relocations. 3755 */ 3756 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3757 } 3758 if (rc) 3759 return rc; 3760 } 3761 3762 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3763 } 3764 3765 static int selinux_file_lock(struct file *file, unsigned int cmd) 3766 { 3767 const struct cred *cred = current_cred(); 3768 3769 return file_has_perm(cred, file, FILE__LOCK); 3770 } 3771 3772 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3773 unsigned long arg) 3774 { 3775 const struct cred *cred = current_cred(); 3776 int err = 0; 3777 3778 switch (cmd) { 3779 case F_SETFL: 3780 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3781 err = file_has_perm(cred, file, FILE__WRITE); 3782 break; 3783 } 3784 fallthrough; 3785 case F_SETOWN: 3786 case F_SETSIG: 3787 case F_GETFL: 3788 case F_GETOWN: 3789 case F_GETSIG: 3790 case F_GETOWNER_UIDS: 3791 /* Just check FD__USE permission */ 3792 err = file_has_perm(cred, file, 0); 3793 break; 3794 case F_GETLK: 3795 case F_SETLK: 3796 case F_SETLKW: 3797 case F_OFD_GETLK: 3798 case F_OFD_SETLK: 3799 case F_OFD_SETLKW: 3800 #if BITS_PER_LONG == 32 3801 case F_GETLK64: 3802 case F_SETLK64: 3803 case F_SETLKW64: 3804 #endif 3805 err = file_has_perm(cred, file, FILE__LOCK); 3806 break; 3807 } 3808 3809 return err; 3810 } 3811 3812 static void selinux_file_set_fowner(struct file *file) 3813 { 3814 struct file_security_struct *fsec; 3815 3816 fsec = selinux_file(file); 3817 fsec->fown_sid = current_sid(); 3818 } 3819 3820 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3821 struct fown_struct *fown, int signum) 3822 { 3823 struct file *file; 3824 u32 sid = task_sid(tsk); 3825 u32 perm; 3826 struct file_security_struct *fsec; 3827 3828 /* struct fown_struct is never outside the context of a struct file */ 3829 file = container_of(fown, struct file, f_owner); 3830 3831 fsec = selinux_file(file); 3832 3833 if (!signum) 3834 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3835 else 3836 perm = signal_to_av(signum); 3837 3838 return avc_has_perm(&selinux_state, 3839 fsec->fown_sid, sid, 3840 SECCLASS_PROCESS, perm, NULL); 3841 } 3842 3843 static int selinux_file_receive(struct file *file) 3844 { 3845 const struct cred *cred = current_cred(); 3846 3847 return file_has_perm(cred, file, file_to_av(file)); 3848 } 3849 3850 static int selinux_file_open(struct file *file) 3851 { 3852 struct file_security_struct *fsec; 3853 struct inode_security_struct *isec; 3854 3855 fsec = selinux_file(file); 3856 isec = inode_security(file_inode(file)); 3857 /* 3858 * Save inode label and policy sequence number 3859 * at open-time so that selinux_file_permission 3860 * can determine whether revalidation is necessary. 3861 * Task label is already saved in the file security 3862 * struct as its SID. 3863 */ 3864 fsec->isid = isec->sid; 3865 fsec->pseqno = avc_policy_seqno(&selinux_state); 3866 /* 3867 * Since the inode label or policy seqno may have changed 3868 * between the selinux_inode_permission check and the saving 3869 * of state above, recheck that access is still permitted. 3870 * Otherwise, access might never be revalidated against the 3871 * new inode label or new policy. 3872 * This check is not redundant - do not remove. 3873 */ 3874 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3875 } 3876 3877 /* task security operations */ 3878 3879 static int selinux_task_alloc(struct task_struct *task, 3880 unsigned long clone_flags) 3881 { 3882 u32 sid = current_sid(); 3883 3884 return avc_has_perm(&selinux_state, 3885 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3886 } 3887 3888 /* 3889 * prepare a new set of credentials for modification 3890 */ 3891 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3892 gfp_t gfp) 3893 { 3894 const struct task_security_struct *old_tsec = selinux_cred(old); 3895 struct task_security_struct *tsec = selinux_cred(new); 3896 3897 *tsec = *old_tsec; 3898 return 0; 3899 } 3900 3901 /* 3902 * transfer the SELinux data to a blank set of creds 3903 */ 3904 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3905 { 3906 const struct task_security_struct *old_tsec = selinux_cred(old); 3907 struct task_security_struct *tsec = selinux_cred(new); 3908 3909 *tsec = *old_tsec; 3910 } 3911 3912 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 3913 { 3914 *secid = cred_sid(c); 3915 } 3916 3917 /* 3918 * set the security data for a kernel service 3919 * - all the creation contexts are set to unlabelled 3920 */ 3921 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3922 { 3923 struct task_security_struct *tsec = selinux_cred(new); 3924 u32 sid = current_sid(); 3925 int ret; 3926 3927 ret = avc_has_perm(&selinux_state, 3928 sid, secid, 3929 SECCLASS_KERNEL_SERVICE, 3930 KERNEL_SERVICE__USE_AS_OVERRIDE, 3931 NULL); 3932 if (ret == 0) { 3933 tsec->sid = secid; 3934 tsec->create_sid = 0; 3935 tsec->keycreate_sid = 0; 3936 tsec->sockcreate_sid = 0; 3937 } 3938 return ret; 3939 } 3940 3941 /* 3942 * set the file creation context in a security record to the same as the 3943 * objective context of the specified inode 3944 */ 3945 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3946 { 3947 struct inode_security_struct *isec = inode_security(inode); 3948 struct task_security_struct *tsec = selinux_cred(new); 3949 u32 sid = current_sid(); 3950 int ret; 3951 3952 ret = avc_has_perm(&selinux_state, 3953 sid, isec->sid, 3954 SECCLASS_KERNEL_SERVICE, 3955 KERNEL_SERVICE__CREATE_FILES_AS, 3956 NULL); 3957 3958 if (ret == 0) 3959 tsec->create_sid = isec->sid; 3960 return ret; 3961 } 3962 3963 static int selinux_kernel_module_request(char *kmod_name) 3964 { 3965 struct common_audit_data ad; 3966 3967 ad.type = LSM_AUDIT_DATA_KMOD; 3968 ad.u.kmod_name = kmod_name; 3969 3970 return avc_has_perm(&selinux_state, 3971 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 3972 SYSTEM__MODULE_REQUEST, &ad); 3973 } 3974 3975 static int selinux_kernel_module_from_file(struct file *file) 3976 { 3977 struct common_audit_data ad; 3978 struct inode_security_struct *isec; 3979 struct file_security_struct *fsec; 3980 u32 sid = current_sid(); 3981 int rc; 3982 3983 /* init_module */ 3984 if (file == NULL) 3985 return avc_has_perm(&selinux_state, 3986 sid, sid, SECCLASS_SYSTEM, 3987 SYSTEM__MODULE_LOAD, NULL); 3988 3989 /* finit_module */ 3990 3991 ad.type = LSM_AUDIT_DATA_FILE; 3992 ad.u.file = file; 3993 3994 fsec = selinux_file(file); 3995 if (sid != fsec->sid) { 3996 rc = avc_has_perm(&selinux_state, 3997 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 3998 if (rc) 3999 return rc; 4000 } 4001 4002 isec = inode_security(file_inode(file)); 4003 return avc_has_perm(&selinux_state, 4004 sid, isec->sid, SECCLASS_SYSTEM, 4005 SYSTEM__MODULE_LOAD, &ad); 4006 } 4007 4008 static int selinux_kernel_read_file(struct file *file, 4009 enum kernel_read_file_id id, 4010 bool contents) 4011 { 4012 int rc = 0; 4013 4014 switch (id) { 4015 case READING_MODULE: 4016 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4017 break; 4018 default: 4019 break; 4020 } 4021 4022 return rc; 4023 } 4024 4025 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4026 { 4027 int rc = 0; 4028 4029 switch (id) { 4030 case LOADING_MODULE: 4031 rc = selinux_kernel_module_from_file(NULL); 4032 default: 4033 break; 4034 } 4035 4036 return rc; 4037 } 4038 4039 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4040 { 4041 return avc_has_perm(&selinux_state, 4042 current_sid(), task_sid(p), SECCLASS_PROCESS, 4043 PROCESS__SETPGID, NULL); 4044 } 4045 4046 static int selinux_task_getpgid(struct task_struct *p) 4047 { 4048 return avc_has_perm(&selinux_state, 4049 current_sid(), task_sid(p), SECCLASS_PROCESS, 4050 PROCESS__GETPGID, NULL); 4051 } 4052 4053 static int selinux_task_getsid(struct task_struct *p) 4054 { 4055 return avc_has_perm(&selinux_state, 4056 current_sid(), task_sid(p), SECCLASS_PROCESS, 4057 PROCESS__GETSESSION, NULL); 4058 } 4059 4060 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 4061 { 4062 *secid = task_sid(p); 4063 } 4064 4065 static int selinux_task_setnice(struct task_struct *p, int nice) 4066 { 4067 return avc_has_perm(&selinux_state, 4068 current_sid(), task_sid(p), SECCLASS_PROCESS, 4069 PROCESS__SETSCHED, NULL); 4070 } 4071 4072 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4073 { 4074 return avc_has_perm(&selinux_state, 4075 current_sid(), task_sid(p), SECCLASS_PROCESS, 4076 PROCESS__SETSCHED, NULL); 4077 } 4078 4079 static int selinux_task_getioprio(struct task_struct *p) 4080 { 4081 return avc_has_perm(&selinux_state, 4082 current_sid(), task_sid(p), SECCLASS_PROCESS, 4083 PROCESS__GETSCHED, NULL); 4084 } 4085 4086 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4087 unsigned int flags) 4088 { 4089 u32 av = 0; 4090 4091 if (!flags) 4092 return 0; 4093 if (flags & LSM_PRLIMIT_WRITE) 4094 av |= PROCESS__SETRLIMIT; 4095 if (flags & LSM_PRLIMIT_READ) 4096 av |= PROCESS__GETRLIMIT; 4097 return avc_has_perm(&selinux_state, 4098 cred_sid(cred), cred_sid(tcred), 4099 SECCLASS_PROCESS, av, NULL); 4100 } 4101 4102 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4103 struct rlimit *new_rlim) 4104 { 4105 struct rlimit *old_rlim = p->signal->rlim + resource; 4106 4107 /* Control the ability to change the hard limit (whether 4108 lowering or raising it), so that the hard limit can 4109 later be used as a safe reset point for the soft limit 4110 upon context transitions. See selinux_bprm_committing_creds. */ 4111 if (old_rlim->rlim_max != new_rlim->rlim_max) 4112 return avc_has_perm(&selinux_state, 4113 current_sid(), task_sid(p), 4114 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4115 4116 return 0; 4117 } 4118 4119 static int selinux_task_setscheduler(struct task_struct *p) 4120 { 4121 return avc_has_perm(&selinux_state, 4122 current_sid(), task_sid(p), SECCLASS_PROCESS, 4123 PROCESS__SETSCHED, NULL); 4124 } 4125 4126 static int selinux_task_getscheduler(struct task_struct *p) 4127 { 4128 return avc_has_perm(&selinux_state, 4129 current_sid(), task_sid(p), SECCLASS_PROCESS, 4130 PROCESS__GETSCHED, NULL); 4131 } 4132 4133 static int selinux_task_movememory(struct task_struct *p) 4134 { 4135 return avc_has_perm(&selinux_state, 4136 current_sid(), task_sid(p), SECCLASS_PROCESS, 4137 PROCESS__SETSCHED, NULL); 4138 } 4139 4140 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4141 int sig, const struct cred *cred) 4142 { 4143 u32 secid; 4144 u32 perm; 4145 4146 if (!sig) 4147 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4148 else 4149 perm = signal_to_av(sig); 4150 if (!cred) 4151 secid = current_sid(); 4152 else 4153 secid = cred_sid(cred); 4154 return avc_has_perm(&selinux_state, 4155 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL); 4156 } 4157 4158 static void selinux_task_to_inode(struct task_struct *p, 4159 struct inode *inode) 4160 { 4161 struct inode_security_struct *isec = selinux_inode(inode); 4162 u32 sid = task_sid(p); 4163 4164 spin_lock(&isec->lock); 4165 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4166 isec->sid = sid; 4167 isec->initialized = LABEL_INITIALIZED; 4168 spin_unlock(&isec->lock); 4169 } 4170 4171 /* Returns error only if unable to parse addresses */ 4172 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4173 struct common_audit_data *ad, u8 *proto) 4174 { 4175 int offset, ihlen, ret = -EINVAL; 4176 struct iphdr _iph, *ih; 4177 4178 offset = skb_network_offset(skb); 4179 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4180 if (ih == NULL) 4181 goto out; 4182 4183 ihlen = ih->ihl * 4; 4184 if (ihlen < sizeof(_iph)) 4185 goto out; 4186 4187 ad->u.net->v4info.saddr = ih->saddr; 4188 ad->u.net->v4info.daddr = ih->daddr; 4189 ret = 0; 4190 4191 if (proto) 4192 *proto = ih->protocol; 4193 4194 switch (ih->protocol) { 4195 case IPPROTO_TCP: { 4196 struct tcphdr _tcph, *th; 4197 4198 if (ntohs(ih->frag_off) & IP_OFFSET) 4199 break; 4200 4201 offset += ihlen; 4202 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4203 if (th == NULL) 4204 break; 4205 4206 ad->u.net->sport = th->source; 4207 ad->u.net->dport = th->dest; 4208 break; 4209 } 4210 4211 case IPPROTO_UDP: { 4212 struct udphdr _udph, *uh; 4213 4214 if (ntohs(ih->frag_off) & IP_OFFSET) 4215 break; 4216 4217 offset += ihlen; 4218 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4219 if (uh == NULL) 4220 break; 4221 4222 ad->u.net->sport = uh->source; 4223 ad->u.net->dport = uh->dest; 4224 break; 4225 } 4226 4227 case IPPROTO_DCCP: { 4228 struct dccp_hdr _dccph, *dh; 4229 4230 if (ntohs(ih->frag_off) & IP_OFFSET) 4231 break; 4232 4233 offset += ihlen; 4234 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4235 if (dh == NULL) 4236 break; 4237 4238 ad->u.net->sport = dh->dccph_sport; 4239 ad->u.net->dport = dh->dccph_dport; 4240 break; 4241 } 4242 4243 #if IS_ENABLED(CONFIG_IP_SCTP) 4244 case IPPROTO_SCTP: { 4245 struct sctphdr _sctph, *sh; 4246 4247 if (ntohs(ih->frag_off) & IP_OFFSET) 4248 break; 4249 4250 offset += ihlen; 4251 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4252 if (sh == NULL) 4253 break; 4254 4255 ad->u.net->sport = sh->source; 4256 ad->u.net->dport = sh->dest; 4257 break; 4258 } 4259 #endif 4260 default: 4261 break; 4262 } 4263 out: 4264 return ret; 4265 } 4266 4267 #if IS_ENABLED(CONFIG_IPV6) 4268 4269 /* Returns error only if unable to parse addresses */ 4270 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4271 struct common_audit_data *ad, u8 *proto) 4272 { 4273 u8 nexthdr; 4274 int ret = -EINVAL, offset; 4275 struct ipv6hdr _ipv6h, *ip6; 4276 __be16 frag_off; 4277 4278 offset = skb_network_offset(skb); 4279 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4280 if (ip6 == NULL) 4281 goto out; 4282 4283 ad->u.net->v6info.saddr = ip6->saddr; 4284 ad->u.net->v6info.daddr = ip6->daddr; 4285 ret = 0; 4286 4287 nexthdr = ip6->nexthdr; 4288 offset += sizeof(_ipv6h); 4289 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4290 if (offset < 0) 4291 goto out; 4292 4293 if (proto) 4294 *proto = nexthdr; 4295 4296 switch (nexthdr) { 4297 case IPPROTO_TCP: { 4298 struct tcphdr _tcph, *th; 4299 4300 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4301 if (th == NULL) 4302 break; 4303 4304 ad->u.net->sport = th->source; 4305 ad->u.net->dport = th->dest; 4306 break; 4307 } 4308 4309 case IPPROTO_UDP: { 4310 struct udphdr _udph, *uh; 4311 4312 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4313 if (uh == NULL) 4314 break; 4315 4316 ad->u.net->sport = uh->source; 4317 ad->u.net->dport = uh->dest; 4318 break; 4319 } 4320 4321 case IPPROTO_DCCP: { 4322 struct dccp_hdr _dccph, *dh; 4323 4324 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4325 if (dh == NULL) 4326 break; 4327 4328 ad->u.net->sport = dh->dccph_sport; 4329 ad->u.net->dport = dh->dccph_dport; 4330 break; 4331 } 4332 4333 #if IS_ENABLED(CONFIG_IP_SCTP) 4334 case IPPROTO_SCTP: { 4335 struct sctphdr _sctph, *sh; 4336 4337 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4338 if (sh == NULL) 4339 break; 4340 4341 ad->u.net->sport = sh->source; 4342 ad->u.net->dport = sh->dest; 4343 break; 4344 } 4345 #endif 4346 /* includes fragments */ 4347 default: 4348 break; 4349 } 4350 out: 4351 return ret; 4352 } 4353 4354 #endif /* IPV6 */ 4355 4356 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4357 char **_addrp, int src, u8 *proto) 4358 { 4359 char *addrp; 4360 int ret; 4361 4362 switch (ad->u.net->family) { 4363 case PF_INET: 4364 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4365 if (ret) 4366 goto parse_error; 4367 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4368 &ad->u.net->v4info.daddr); 4369 goto okay; 4370 4371 #if IS_ENABLED(CONFIG_IPV6) 4372 case PF_INET6: 4373 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4374 if (ret) 4375 goto parse_error; 4376 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4377 &ad->u.net->v6info.daddr); 4378 goto okay; 4379 #endif /* IPV6 */ 4380 default: 4381 addrp = NULL; 4382 goto okay; 4383 } 4384 4385 parse_error: 4386 pr_warn( 4387 "SELinux: failure in selinux_parse_skb()," 4388 " unable to parse packet\n"); 4389 return ret; 4390 4391 okay: 4392 if (_addrp) 4393 *_addrp = addrp; 4394 return 0; 4395 } 4396 4397 /** 4398 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4399 * @skb: the packet 4400 * @family: protocol family 4401 * @sid: the packet's peer label SID 4402 * 4403 * Description: 4404 * Check the various different forms of network peer labeling and determine 4405 * the peer label/SID for the packet; most of the magic actually occurs in 4406 * the security server function security_net_peersid_cmp(). The function 4407 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4408 * or -EACCES if @sid is invalid due to inconsistencies with the different 4409 * peer labels. 4410 * 4411 */ 4412 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4413 { 4414 int err; 4415 u32 xfrm_sid; 4416 u32 nlbl_sid; 4417 u32 nlbl_type; 4418 4419 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4420 if (unlikely(err)) 4421 return -EACCES; 4422 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4423 if (unlikely(err)) 4424 return -EACCES; 4425 4426 err = security_net_peersid_resolve(&selinux_state, nlbl_sid, 4427 nlbl_type, xfrm_sid, sid); 4428 if (unlikely(err)) { 4429 pr_warn( 4430 "SELinux: failure in selinux_skb_peerlbl_sid()," 4431 " unable to determine packet's peer label\n"); 4432 return -EACCES; 4433 } 4434 4435 return 0; 4436 } 4437 4438 /** 4439 * selinux_conn_sid - Determine the child socket label for a connection 4440 * @sk_sid: the parent socket's SID 4441 * @skb_sid: the packet's SID 4442 * @conn_sid: the resulting connection SID 4443 * 4444 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4445 * combined with the MLS information from @skb_sid in order to create 4446 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4447 * of @sk_sid. Returns zero on success, negative values on failure. 4448 * 4449 */ 4450 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4451 { 4452 int err = 0; 4453 4454 if (skb_sid != SECSID_NULL) 4455 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid, 4456 conn_sid); 4457 else 4458 *conn_sid = sk_sid; 4459 4460 return err; 4461 } 4462 4463 /* socket security operations */ 4464 4465 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4466 u16 secclass, u32 *socksid) 4467 { 4468 if (tsec->sockcreate_sid > SECSID_NULL) { 4469 *socksid = tsec->sockcreate_sid; 4470 return 0; 4471 } 4472 4473 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid, 4474 secclass, NULL, socksid); 4475 } 4476 4477 static int sock_has_perm(struct sock *sk, u32 perms) 4478 { 4479 struct sk_security_struct *sksec = sk->sk_security; 4480 struct common_audit_data ad; 4481 struct lsm_network_audit net = {0,}; 4482 4483 if (sksec->sid == SECINITSID_KERNEL) 4484 return 0; 4485 4486 ad.type = LSM_AUDIT_DATA_NET; 4487 ad.u.net = &net; 4488 ad.u.net->sk = sk; 4489 4490 return avc_has_perm(&selinux_state, 4491 current_sid(), sksec->sid, sksec->sclass, perms, 4492 &ad); 4493 } 4494 4495 static int selinux_socket_create(int family, int type, 4496 int protocol, int kern) 4497 { 4498 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4499 u32 newsid; 4500 u16 secclass; 4501 int rc; 4502 4503 if (kern) 4504 return 0; 4505 4506 secclass = socket_type_to_security_class(family, type, protocol); 4507 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4508 if (rc) 4509 return rc; 4510 4511 return avc_has_perm(&selinux_state, 4512 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4513 } 4514 4515 static int selinux_socket_post_create(struct socket *sock, int family, 4516 int type, int protocol, int kern) 4517 { 4518 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4519 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4520 struct sk_security_struct *sksec; 4521 u16 sclass = socket_type_to_security_class(family, type, protocol); 4522 u32 sid = SECINITSID_KERNEL; 4523 int err = 0; 4524 4525 if (!kern) { 4526 err = socket_sockcreate_sid(tsec, sclass, &sid); 4527 if (err) 4528 return err; 4529 } 4530 4531 isec->sclass = sclass; 4532 isec->sid = sid; 4533 isec->initialized = LABEL_INITIALIZED; 4534 4535 if (sock->sk) { 4536 sksec = sock->sk->sk_security; 4537 sksec->sclass = sclass; 4538 sksec->sid = sid; 4539 /* Allows detection of the first association on this socket */ 4540 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4541 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4542 4543 err = selinux_netlbl_socket_post_create(sock->sk, family); 4544 } 4545 4546 return err; 4547 } 4548 4549 static int selinux_socket_socketpair(struct socket *socka, 4550 struct socket *sockb) 4551 { 4552 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4553 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4554 4555 sksec_a->peer_sid = sksec_b->sid; 4556 sksec_b->peer_sid = sksec_a->sid; 4557 4558 return 0; 4559 } 4560 4561 /* Range of port numbers used to automatically bind. 4562 Need to determine whether we should perform a name_bind 4563 permission check between the socket and the port number. */ 4564 4565 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4566 { 4567 struct sock *sk = sock->sk; 4568 struct sk_security_struct *sksec = sk->sk_security; 4569 u16 family; 4570 int err; 4571 4572 err = sock_has_perm(sk, SOCKET__BIND); 4573 if (err) 4574 goto out; 4575 4576 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4577 family = sk->sk_family; 4578 if (family == PF_INET || family == PF_INET6) { 4579 char *addrp; 4580 struct common_audit_data ad; 4581 struct lsm_network_audit net = {0,}; 4582 struct sockaddr_in *addr4 = NULL; 4583 struct sockaddr_in6 *addr6 = NULL; 4584 u16 family_sa; 4585 unsigned short snum; 4586 u32 sid, node_perm; 4587 4588 /* 4589 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4590 * that validates multiple binding addresses. Because of this 4591 * need to check address->sa_family as it is possible to have 4592 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4593 */ 4594 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4595 return -EINVAL; 4596 family_sa = address->sa_family; 4597 switch (family_sa) { 4598 case AF_UNSPEC: 4599 case AF_INET: 4600 if (addrlen < sizeof(struct sockaddr_in)) 4601 return -EINVAL; 4602 addr4 = (struct sockaddr_in *)address; 4603 if (family_sa == AF_UNSPEC) { 4604 /* see __inet_bind(), we only want to allow 4605 * AF_UNSPEC if the address is INADDR_ANY 4606 */ 4607 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4608 goto err_af; 4609 family_sa = AF_INET; 4610 } 4611 snum = ntohs(addr4->sin_port); 4612 addrp = (char *)&addr4->sin_addr.s_addr; 4613 break; 4614 case AF_INET6: 4615 if (addrlen < SIN6_LEN_RFC2133) 4616 return -EINVAL; 4617 addr6 = (struct sockaddr_in6 *)address; 4618 snum = ntohs(addr6->sin6_port); 4619 addrp = (char *)&addr6->sin6_addr.s6_addr; 4620 break; 4621 default: 4622 goto err_af; 4623 } 4624 4625 ad.type = LSM_AUDIT_DATA_NET; 4626 ad.u.net = &net; 4627 ad.u.net->sport = htons(snum); 4628 ad.u.net->family = family_sa; 4629 4630 if (snum) { 4631 int low, high; 4632 4633 inet_get_local_port_range(sock_net(sk), &low, &high); 4634 4635 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4636 snum < low || snum > high) { 4637 err = sel_netport_sid(sk->sk_protocol, 4638 snum, &sid); 4639 if (err) 4640 goto out; 4641 err = avc_has_perm(&selinux_state, 4642 sksec->sid, sid, 4643 sksec->sclass, 4644 SOCKET__NAME_BIND, &ad); 4645 if (err) 4646 goto out; 4647 } 4648 } 4649 4650 switch (sksec->sclass) { 4651 case SECCLASS_TCP_SOCKET: 4652 node_perm = TCP_SOCKET__NODE_BIND; 4653 break; 4654 4655 case SECCLASS_UDP_SOCKET: 4656 node_perm = UDP_SOCKET__NODE_BIND; 4657 break; 4658 4659 case SECCLASS_DCCP_SOCKET: 4660 node_perm = DCCP_SOCKET__NODE_BIND; 4661 break; 4662 4663 case SECCLASS_SCTP_SOCKET: 4664 node_perm = SCTP_SOCKET__NODE_BIND; 4665 break; 4666 4667 default: 4668 node_perm = RAWIP_SOCKET__NODE_BIND; 4669 break; 4670 } 4671 4672 err = sel_netnode_sid(addrp, family_sa, &sid); 4673 if (err) 4674 goto out; 4675 4676 if (family_sa == AF_INET) 4677 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4678 else 4679 ad.u.net->v6info.saddr = addr6->sin6_addr; 4680 4681 err = avc_has_perm(&selinux_state, 4682 sksec->sid, sid, 4683 sksec->sclass, node_perm, &ad); 4684 if (err) 4685 goto out; 4686 } 4687 out: 4688 return err; 4689 err_af: 4690 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4691 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4692 return -EINVAL; 4693 return -EAFNOSUPPORT; 4694 } 4695 4696 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4697 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4698 */ 4699 static int selinux_socket_connect_helper(struct socket *sock, 4700 struct sockaddr *address, int addrlen) 4701 { 4702 struct sock *sk = sock->sk; 4703 struct sk_security_struct *sksec = sk->sk_security; 4704 int err; 4705 4706 err = sock_has_perm(sk, SOCKET__CONNECT); 4707 if (err) 4708 return err; 4709 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4710 return -EINVAL; 4711 4712 /* connect(AF_UNSPEC) has special handling, as it is a documented 4713 * way to disconnect the socket 4714 */ 4715 if (address->sa_family == AF_UNSPEC) 4716 return 0; 4717 4718 /* 4719 * If a TCP, DCCP or SCTP socket, check name_connect permission 4720 * for the port. 4721 */ 4722 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4723 sksec->sclass == SECCLASS_DCCP_SOCKET || 4724 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4725 struct common_audit_data ad; 4726 struct lsm_network_audit net = {0,}; 4727 struct sockaddr_in *addr4 = NULL; 4728 struct sockaddr_in6 *addr6 = NULL; 4729 unsigned short snum; 4730 u32 sid, perm; 4731 4732 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4733 * that validates multiple connect addresses. Because of this 4734 * need to check address->sa_family as it is possible to have 4735 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4736 */ 4737 switch (address->sa_family) { 4738 case AF_INET: 4739 addr4 = (struct sockaddr_in *)address; 4740 if (addrlen < sizeof(struct sockaddr_in)) 4741 return -EINVAL; 4742 snum = ntohs(addr4->sin_port); 4743 break; 4744 case AF_INET6: 4745 addr6 = (struct sockaddr_in6 *)address; 4746 if (addrlen < SIN6_LEN_RFC2133) 4747 return -EINVAL; 4748 snum = ntohs(addr6->sin6_port); 4749 break; 4750 default: 4751 /* Note that SCTP services expect -EINVAL, whereas 4752 * others expect -EAFNOSUPPORT. 4753 */ 4754 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4755 return -EINVAL; 4756 else 4757 return -EAFNOSUPPORT; 4758 } 4759 4760 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4761 if (err) 4762 return err; 4763 4764 switch (sksec->sclass) { 4765 case SECCLASS_TCP_SOCKET: 4766 perm = TCP_SOCKET__NAME_CONNECT; 4767 break; 4768 case SECCLASS_DCCP_SOCKET: 4769 perm = DCCP_SOCKET__NAME_CONNECT; 4770 break; 4771 case SECCLASS_SCTP_SOCKET: 4772 perm = SCTP_SOCKET__NAME_CONNECT; 4773 break; 4774 } 4775 4776 ad.type = LSM_AUDIT_DATA_NET; 4777 ad.u.net = &net; 4778 ad.u.net->dport = htons(snum); 4779 ad.u.net->family = address->sa_family; 4780 err = avc_has_perm(&selinux_state, 4781 sksec->sid, sid, sksec->sclass, perm, &ad); 4782 if (err) 4783 return err; 4784 } 4785 4786 return 0; 4787 } 4788 4789 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4790 static int selinux_socket_connect(struct socket *sock, 4791 struct sockaddr *address, int addrlen) 4792 { 4793 int err; 4794 struct sock *sk = sock->sk; 4795 4796 err = selinux_socket_connect_helper(sock, address, addrlen); 4797 if (err) 4798 return err; 4799 4800 return selinux_netlbl_socket_connect(sk, address); 4801 } 4802 4803 static int selinux_socket_listen(struct socket *sock, int backlog) 4804 { 4805 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4806 } 4807 4808 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4809 { 4810 int err; 4811 struct inode_security_struct *isec; 4812 struct inode_security_struct *newisec; 4813 u16 sclass; 4814 u32 sid; 4815 4816 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4817 if (err) 4818 return err; 4819 4820 isec = inode_security_novalidate(SOCK_INODE(sock)); 4821 spin_lock(&isec->lock); 4822 sclass = isec->sclass; 4823 sid = isec->sid; 4824 spin_unlock(&isec->lock); 4825 4826 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4827 newisec->sclass = sclass; 4828 newisec->sid = sid; 4829 newisec->initialized = LABEL_INITIALIZED; 4830 4831 return 0; 4832 } 4833 4834 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4835 int size) 4836 { 4837 return sock_has_perm(sock->sk, SOCKET__WRITE); 4838 } 4839 4840 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4841 int size, int flags) 4842 { 4843 return sock_has_perm(sock->sk, SOCKET__READ); 4844 } 4845 4846 static int selinux_socket_getsockname(struct socket *sock) 4847 { 4848 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4849 } 4850 4851 static int selinux_socket_getpeername(struct socket *sock) 4852 { 4853 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4854 } 4855 4856 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4857 { 4858 int err; 4859 4860 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4861 if (err) 4862 return err; 4863 4864 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4865 } 4866 4867 static int selinux_socket_getsockopt(struct socket *sock, int level, 4868 int optname) 4869 { 4870 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4871 } 4872 4873 static int selinux_socket_shutdown(struct socket *sock, int how) 4874 { 4875 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4876 } 4877 4878 static int selinux_socket_unix_stream_connect(struct sock *sock, 4879 struct sock *other, 4880 struct sock *newsk) 4881 { 4882 struct sk_security_struct *sksec_sock = sock->sk_security; 4883 struct sk_security_struct *sksec_other = other->sk_security; 4884 struct sk_security_struct *sksec_new = newsk->sk_security; 4885 struct common_audit_data ad; 4886 struct lsm_network_audit net = {0,}; 4887 int err; 4888 4889 ad.type = LSM_AUDIT_DATA_NET; 4890 ad.u.net = &net; 4891 ad.u.net->sk = other; 4892 4893 err = avc_has_perm(&selinux_state, 4894 sksec_sock->sid, sksec_other->sid, 4895 sksec_other->sclass, 4896 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4897 if (err) 4898 return err; 4899 4900 /* server child socket */ 4901 sksec_new->peer_sid = sksec_sock->sid; 4902 err = security_sid_mls_copy(&selinux_state, sksec_other->sid, 4903 sksec_sock->sid, &sksec_new->sid); 4904 if (err) 4905 return err; 4906 4907 /* connecting socket */ 4908 sksec_sock->peer_sid = sksec_new->sid; 4909 4910 return 0; 4911 } 4912 4913 static int selinux_socket_unix_may_send(struct socket *sock, 4914 struct socket *other) 4915 { 4916 struct sk_security_struct *ssec = sock->sk->sk_security; 4917 struct sk_security_struct *osec = other->sk->sk_security; 4918 struct common_audit_data ad; 4919 struct lsm_network_audit net = {0,}; 4920 4921 ad.type = LSM_AUDIT_DATA_NET; 4922 ad.u.net = &net; 4923 ad.u.net->sk = other->sk; 4924 4925 return avc_has_perm(&selinux_state, 4926 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4927 &ad); 4928 } 4929 4930 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4931 char *addrp, u16 family, u32 peer_sid, 4932 struct common_audit_data *ad) 4933 { 4934 int err; 4935 u32 if_sid; 4936 u32 node_sid; 4937 4938 err = sel_netif_sid(ns, ifindex, &if_sid); 4939 if (err) 4940 return err; 4941 err = avc_has_perm(&selinux_state, 4942 peer_sid, if_sid, 4943 SECCLASS_NETIF, NETIF__INGRESS, ad); 4944 if (err) 4945 return err; 4946 4947 err = sel_netnode_sid(addrp, family, &node_sid); 4948 if (err) 4949 return err; 4950 return avc_has_perm(&selinux_state, 4951 peer_sid, node_sid, 4952 SECCLASS_NODE, NODE__RECVFROM, ad); 4953 } 4954 4955 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4956 u16 family) 4957 { 4958 int err = 0; 4959 struct sk_security_struct *sksec = sk->sk_security; 4960 u32 sk_sid = sksec->sid; 4961 struct common_audit_data ad; 4962 struct lsm_network_audit net = {0,}; 4963 char *addrp; 4964 4965 ad.type = LSM_AUDIT_DATA_NET; 4966 ad.u.net = &net; 4967 ad.u.net->netif = skb->skb_iif; 4968 ad.u.net->family = family; 4969 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4970 if (err) 4971 return err; 4972 4973 if (selinux_secmark_enabled()) { 4974 err = avc_has_perm(&selinux_state, 4975 sk_sid, skb->secmark, SECCLASS_PACKET, 4976 PACKET__RECV, &ad); 4977 if (err) 4978 return err; 4979 } 4980 4981 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4982 if (err) 4983 return err; 4984 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4985 4986 return err; 4987 } 4988 4989 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4990 { 4991 int err; 4992 struct sk_security_struct *sksec = sk->sk_security; 4993 u16 family = sk->sk_family; 4994 u32 sk_sid = sksec->sid; 4995 struct common_audit_data ad; 4996 struct lsm_network_audit net = {0,}; 4997 char *addrp; 4998 u8 secmark_active; 4999 u8 peerlbl_active; 5000 5001 if (family != PF_INET && family != PF_INET6) 5002 return 0; 5003 5004 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5005 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5006 family = PF_INET; 5007 5008 /* If any sort of compatibility mode is enabled then handoff processing 5009 * to the selinux_sock_rcv_skb_compat() function to deal with the 5010 * special handling. We do this in an attempt to keep this function 5011 * as fast and as clean as possible. */ 5012 if (!selinux_policycap_netpeer()) 5013 return selinux_sock_rcv_skb_compat(sk, skb, family); 5014 5015 secmark_active = selinux_secmark_enabled(); 5016 peerlbl_active = selinux_peerlbl_enabled(); 5017 if (!secmark_active && !peerlbl_active) 5018 return 0; 5019 5020 ad.type = LSM_AUDIT_DATA_NET; 5021 ad.u.net = &net; 5022 ad.u.net->netif = skb->skb_iif; 5023 ad.u.net->family = family; 5024 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5025 if (err) 5026 return err; 5027 5028 if (peerlbl_active) { 5029 u32 peer_sid; 5030 5031 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5032 if (err) 5033 return err; 5034 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5035 addrp, family, peer_sid, &ad); 5036 if (err) { 5037 selinux_netlbl_err(skb, family, err, 0); 5038 return err; 5039 } 5040 err = avc_has_perm(&selinux_state, 5041 sk_sid, peer_sid, SECCLASS_PEER, 5042 PEER__RECV, &ad); 5043 if (err) { 5044 selinux_netlbl_err(skb, family, err, 0); 5045 return err; 5046 } 5047 } 5048 5049 if (secmark_active) { 5050 err = avc_has_perm(&selinux_state, 5051 sk_sid, skb->secmark, SECCLASS_PACKET, 5052 PACKET__RECV, &ad); 5053 if (err) 5054 return err; 5055 } 5056 5057 return err; 5058 } 5059 5060 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 5061 int __user *optlen, unsigned len) 5062 { 5063 int err = 0; 5064 char *scontext; 5065 u32 scontext_len; 5066 struct sk_security_struct *sksec = sock->sk->sk_security; 5067 u32 peer_sid = SECSID_NULL; 5068 5069 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5070 sksec->sclass == SECCLASS_TCP_SOCKET || 5071 sksec->sclass == SECCLASS_SCTP_SOCKET) 5072 peer_sid = sksec->peer_sid; 5073 if (peer_sid == SECSID_NULL) 5074 return -ENOPROTOOPT; 5075 5076 err = security_sid_to_context(&selinux_state, peer_sid, &scontext, 5077 &scontext_len); 5078 if (err) 5079 return err; 5080 5081 if (scontext_len > len) { 5082 err = -ERANGE; 5083 goto out_len; 5084 } 5085 5086 if (copy_to_user(optval, scontext, scontext_len)) 5087 err = -EFAULT; 5088 5089 out_len: 5090 if (put_user(scontext_len, optlen)) 5091 err = -EFAULT; 5092 kfree(scontext); 5093 return err; 5094 } 5095 5096 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5097 { 5098 u32 peer_secid = SECSID_NULL; 5099 u16 family; 5100 struct inode_security_struct *isec; 5101 5102 if (skb && skb->protocol == htons(ETH_P_IP)) 5103 family = PF_INET; 5104 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5105 family = PF_INET6; 5106 else if (sock) 5107 family = sock->sk->sk_family; 5108 else 5109 goto out; 5110 5111 if (sock && family == PF_UNIX) { 5112 isec = inode_security_novalidate(SOCK_INODE(sock)); 5113 peer_secid = isec->sid; 5114 } else if (skb) 5115 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5116 5117 out: 5118 *secid = peer_secid; 5119 if (peer_secid == SECSID_NULL) 5120 return -EINVAL; 5121 return 0; 5122 } 5123 5124 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5125 { 5126 struct sk_security_struct *sksec; 5127 5128 sksec = kzalloc(sizeof(*sksec), priority); 5129 if (!sksec) 5130 return -ENOMEM; 5131 5132 sksec->peer_sid = SECINITSID_UNLABELED; 5133 sksec->sid = SECINITSID_UNLABELED; 5134 sksec->sclass = SECCLASS_SOCKET; 5135 selinux_netlbl_sk_security_reset(sksec); 5136 sk->sk_security = sksec; 5137 5138 return 0; 5139 } 5140 5141 static void selinux_sk_free_security(struct sock *sk) 5142 { 5143 struct sk_security_struct *sksec = sk->sk_security; 5144 5145 sk->sk_security = NULL; 5146 selinux_netlbl_sk_security_free(sksec); 5147 kfree(sksec); 5148 } 5149 5150 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5151 { 5152 struct sk_security_struct *sksec = sk->sk_security; 5153 struct sk_security_struct *newsksec = newsk->sk_security; 5154 5155 newsksec->sid = sksec->sid; 5156 newsksec->peer_sid = sksec->peer_sid; 5157 newsksec->sclass = sksec->sclass; 5158 5159 selinux_netlbl_sk_security_reset(newsksec); 5160 } 5161 5162 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 5163 { 5164 if (!sk) 5165 *secid = SECINITSID_ANY_SOCKET; 5166 else { 5167 struct sk_security_struct *sksec = sk->sk_security; 5168 5169 *secid = sksec->sid; 5170 } 5171 } 5172 5173 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5174 { 5175 struct inode_security_struct *isec = 5176 inode_security_novalidate(SOCK_INODE(parent)); 5177 struct sk_security_struct *sksec = sk->sk_security; 5178 5179 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5180 sk->sk_family == PF_UNIX) 5181 isec->sid = sksec->sid; 5182 sksec->sclass = isec->sclass; 5183 } 5184 5185 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming 5186 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association 5187 * already present). 5188 */ 5189 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep, 5190 struct sk_buff *skb) 5191 { 5192 struct sk_security_struct *sksec = ep->base.sk->sk_security; 5193 struct common_audit_data ad; 5194 struct lsm_network_audit net = {0,}; 5195 u8 peerlbl_active; 5196 u32 peer_sid = SECINITSID_UNLABELED; 5197 u32 conn_sid; 5198 int err = 0; 5199 5200 if (!selinux_policycap_extsockclass()) 5201 return 0; 5202 5203 peerlbl_active = selinux_peerlbl_enabled(); 5204 5205 if (peerlbl_active) { 5206 /* This will return peer_sid = SECSID_NULL if there are 5207 * no peer labels, see security_net_peersid_resolve(). 5208 */ 5209 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family, 5210 &peer_sid); 5211 if (err) 5212 return err; 5213 5214 if (peer_sid == SECSID_NULL) 5215 peer_sid = SECINITSID_UNLABELED; 5216 } 5217 5218 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5219 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5220 5221 /* Here as first association on socket. As the peer SID 5222 * was allowed by peer recv (and the netif/node checks), 5223 * then it is approved by policy and used as the primary 5224 * peer SID for getpeercon(3). 5225 */ 5226 sksec->peer_sid = peer_sid; 5227 } else if (sksec->peer_sid != peer_sid) { 5228 /* Other association peer SIDs are checked to enforce 5229 * consistency among the peer SIDs. 5230 */ 5231 ad.type = LSM_AUDIT_DATA_NET; 5232 ad.u.net = &net; 5233 ad.u.net->sk = ep->base.sk; 5234 err = avc_has_perm(&selinux_state, 5235 sksec->peer_sid, peer_sid, sksec->sclass, 5236 SCTP_SOCKET__ASSOCIATION, &ad); 5237 if (err) 5238 return err; 5239 } 5240 5241 /* Compute the MLS component for the connection and store 5242 * the information in ep. This will be used by SCTP TCP type 5243 * sockets and peeled off connections as they cause a new 5244 * socket to be generated. selinux_sctp_sk_clone() will then 5245 * plug this into the new socket. 5246 */ 5247 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid); 5248 if (err) 5249 return err; 5250 5251 ep->secid = conn_sid; 5252 ep->peer_secid = peer_sid; 5253 5254 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5255 return selinux_netlbl_sctp_assoc_request(ep, skb); 5256 } 5257 5258 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5259 * based on their @optname. 5260 */ 5261 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5262 struct sockaddr *address, 5263 int addrlen) 5264 { 5265 int len, err = 0, walk_size = 0; 5266 void *addr_buf; 5267 struct sockaddr *addr; 5268 struct socket *sock; 5269 5270 if (!selinux_policycap_extsockclass()) 5271 return 0; 5272 5273 /* Process one or more addresses that may be IPv4 or IPv6 */ 5274 sock = sk->sk_socket; 5275 addr_buf = address; 5276 5277 while (walk_size < addrlen) { 5278 if (walk_size + sizeof(sa_family_t) > addrlen) 5279 return -EINVAL; 5280 5281 addr = addr_buf; 5282 switch (addr->sa_family) { 5283 case AF_UNSPEC: 5284 case AF_INET: 5285 len = sizeof(struct sockaddr_in); 5286 break; 5287 case AF_INET6: 5288 len = sizeof(struct sockaddr_in6); 5289 break; 5290 default: 5291 return -EINVAL; 5292 } 5293 5294 if (walk_size + len > addrlen) 5295 return -EINVAL; 5296 5297 err = -EINVAL; 5298 switch (optname) { 5299 /* Bind checks */ 5300 case SCTP_PRIMARY_ADDR: 5301 case SCTP_SET_PEER_PRIMARY_ADDR: 5302 case SCTP_SOCKOPT_BINDX_ADD: 5303 err = selinux_socket_bind(sock, addr, len); 5304 break; 5305 /* Connect checks */ 5306 case SCTP_SOCKOPT_CONNECTX: 5307 case SCTP_PARAM_SET_PRIMARY: 5308 case SCTP_PARAM_ADD_IP: 5309 case SCTP_SENDMSG_CONNECT: 5310 err = selinux_socket_connect_helper(sock, addr, len); 5311 if (err) 5312 return err; 5313 5314 /* As selinux_sctp_bind_connect() is called by the 5315 * SCTP protocol layer, the socket is already locked, 5316 * therefore selinux_netlbl_socket_connect_locked() 5317 * is called here. The situations handled are: 5318 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5319 * whenever a new IP address is added or when a new 5320 * primary address is selected. 5321 * Note that an SCTP connect(2) call happens before 5322 * the SCTP protocol layer and is handled via 5323 * selinux_socket_connect(). 5324 */ 5325 err = selinux_netlbl_socket_connect_locked(sk, addr); 5326 break; 5327 } 5328 5329 if (err) 5330 return err; 5331 5332 addr_buf += len; 5333 walk_size += len; 5334 } 5335 5336 return 0; 5337 } 5338 5339 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5340 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk, 5341 struct sock *newsk) 5342 { 5343 struct sk_security_struct *sksec = sk->sk_security; 5344 struct sk_security_struct *newsksec = newsk->sk_security; 5345 5346 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5347 * the non-sctp clone version. 5348 */ 5349 if (!selinux_policycap_extsockclass()) 5350 return selinux_sk_clone_security(sk, newsk); 5351 5352 newsksec->sid = ep->secid; 5353 newsksec->peer_sid = ep->peer_secid; 5354 newsksec->sclass = sksec->sclass; 5355 selinux_netlbl_sctp_sk_clone(sk, newsk); 5356 } 5357 5358 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5359 struct request_sock *req) 5360 { 5361 struct sk_security_struct *sksec = sk->sk_security; 5362 int err; 5363 u16 family = req->rsk_ops->family; 5364 u32 connsid; 5365 u32 peersid; 5366 5367 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5368 if (err) 5369 return err; 5370 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5371 if (err) 5372 return err; 5373 req->secid = connsid; 5374 req->peer_secid = peersid; 5375 5376 return selinux_netlbl_inet_conn_request(req, family); 5377 } 5378 5379 static void selinux_inet_csk_clone(struct sock *newsk, 5380 const struct request_sock *req) 5381 { 5382 struct sk_security_struct *newsksec = newsk->sk_security; 5383 5384 newsksec->sid = req->secid; 5385 newsksec->peer_sid = req->peer_secid; 5386 /* NOTE: Ideally, we should also get the isec->sid for the 5387 new socket in sync, but we don't have the isec available yet. 5388 So we will wait until sock_graft to do it, by which 5389 time it will have been created and available. */ 5390 5391 /* We don't need to take any sort of lock here as we are the only 5392 * thread with access to newsksec */ 5393 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5394 } 5395 5396 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5397 { 5398 u16 family = sk->sk_family; 5399 struct sk_security_struct *sksec = sk->sk_security; 5400 5401 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5402 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5403 family = PF_INET; 5404 5405 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5406 } 5407 5408 static int selinux_secmark_relabel_packet(u32 sid) 5409 { 5410 const struct task_security_struct *__tsec; 5411 u32 tsid; 5412 5413 __tsec = selinux_cred(current_cred()); 5414 tsid = __tsec->sid; 5415 5416 return avc_has_perm(&selinux_state, 5417 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5418 NULL); 5419 } 5420 5421 static void selinux_secmark_refcount_inc(void) 5422 { 5423 atomic_inc(&selinux_secmark_refcount); 5424 } 5425 5426 static void selinux_secmark_refcount_dec(void) 5427 { 5428 atomic_dec(&selinux_secmark_refcount); 5429 } 5430 5431 static void selinux_req_classify_flow(const struct request_sock *req, 5432 struct flowi *fl) 5433 { 5434 fl->flowi_secid = req->secid; 5435 } 5436 5437 static int selinux_tun_dev_alloc_security(void **security) 5438 { 5439 struct tun_security_struct *tunsec; 5440 5441 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5442 if (!tunsec) 5443 return -ENOMEM; 5444 tunsec->sid = current_sid(); 5445 5446 *security = tunsec; 5447 return 0; 5448 } 5449 5450 static void selinux_tun_dev_free_security(void *security) 5451 { 5452 kfree(security); 5453 } 5454 5455 static int selinux_tun_dev_create(void) 5456 { 5457 u32 sid = current_sid(); 5458 5459 /* we aren't taking into account the "sockcreate" SID since the socket 5460 * that is being created here is not a socket in the traditional sense, 5461 * instead it is a private sock, accessible only to the kernel, and 5462 * representing a wide range of network traffic spanning multiple 5463 * connections unlike traditional sockets - check the TUN driver to 5464 * get a better understanding of why this socket is special */ 5465 5466 return avc_has_perm(&selinux_state, 5467 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5468 NULL); 5469 } 5470 5471 static int selinux_tun_dev_attach_queue(void *security) 5472 { 5473 struct tun_security_struct *tunsec = security; 5474 5475 return avc_has_perm(&selinux_state, 5476 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5477 TUN_SOCKET__ATTACH_QUEUE, NULL); 5478 } 5479 5480 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5481 { 5482 struct tun_security_struct *tunsec = security; 5483 struct sk_security_struct *sksec = sk->sk_security; 5484 5485 /* we don't currently perform any NetLabel based labeling here and it 5486 * isn't clear that we would want to do so anyway; while we could apply 5487 * labeling without the support of the TUN user the resulting labeled 5488 * traffic from the other end of the connection would almost certainly 5489 * cause confusion to the TUN user that had no idea network labeling 5490 * protocols were being used */ 5491 5492 sksec->sid = tunsec->sid; 5493 sksec->sclass = SECCLASS_TUN_SOCKET; 5494 5495 return 0; 5496 } 5497 5498 static int selinux_tun_dev_open(void *security) 5499 { 5500 struct tun_security_struct *tunsec = security; 5501 u32 sid = current_sid(); 5502 int err; 5503 5504 err = avc_has_perm(&selinux_state, 5505 sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5506 TUN_SOCKET__RELABELFROM, NULL); 5507 if (err) 5508 return err; 5509 err = avc_has_perm(&selinux_state, 5510 sid, sid, SECCLASS_TUN_SOCKET, 5511 TUN_SOCKET__RELABELTO, NULL); 5512 if (err) 5513 return err; 5514 tunsec->sid = sid; 5515 5516 return 0; 5517 } 5518 5519 #ifdef CONFIG_NETFILTER 5520 5521 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5522 const struct net_device *indev, 5523 u16 family) 5524 { 5525 int err; 5526 char *addrp; 5527 u32 peer_sid; 5528 struct common_audit_data ad; 5529 struct lsm_network_audit net = {0,}; 5530 u8 secmark_active; 5531 u8 netlbl_active; 5532 u8 peerlbl_active; 5533 5534 if (!selinux_policycap_netpeer()) 5535 return NF_ACCEPT; 5536 5537 secmark_active = selinux_secmark_enabled(); 5538 netlbl_active = netlbl_enabled(); 5539 peerlbl_active = selinux_peerlbl_enabled(); 5540 if (!secmark_active && !peerlbl_active) 5541 return NF_ACCEPT; 5542 5543 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5544 return NF_DROP; 5545 5546 ad.type = LSM_AUDIT_DATA_NET; 5547 ad.u.net = &net; 5548 ad.u.net->netif = indev->ifindex; 5549 ad.u.net->family = family; 5550 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5551 return NF_DROP; 5552 5553 if (peerlbl_active) { 5554 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5555 addrp, family, peer_sid, &ad); 5556 if (err) { 5557 selinux_netlbl_err(skb, family, err, 1); 5558 return NF_DROP; 5559 } 5560 } 5561 5562 if (secmark_active) 5563 if (avc_has_perm(&selinux_state, 5564 peer_sid, skb->secmark, 5565 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5566 return NF_DROP; 5567 5568 if (netlbl_active) 5569 /* we do this in the FORWARD path and not the POST_ROUTING 5570 * path because we want to make sure we apply the necessary 5571 * labeling before IPsec is applied so we can leverage AH 5572 * protection */ 5573 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5574 return NF_DROP; 5575 5576 return NF_ACCEPT; 5577 } 5578 5579 static unsigned int selinux_ipv4_forward(void *priv, 5580 struct sk_buff *skb, 5581 const struct nf_hook_state *state) 5582 { 5583 return selinux_ip_forward(skb, state->in, PF_INET); 5584 } 5585 5586 #if IS_ENABLED(CONFIG_IPV6) 5587 static unsigned int selinux_ipv6_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_INET6); 5592 } 5593 #endif /* IPV6 */ 5594 5595 static unsigned int selinux_ip_output(struct sk_buff *skb, 5596 u16 family) 5597 { 5598 struct sock *sk; 5599 u32 sid; 5600 5601 if (!netlbl_enabled()) 5602 return NF_ACCEPT; 5603 5604 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5605 * because we want to make sure we apply the necessary labeling 5606 * before IPsec is applied so we can leverage AH protection */ 5607 sk = skb->sk; 5608 if (sk) { 5609 struct sk_security_struct *sksec; 5610 5611 if (sk_listener(sk)) 5612 /* if the socket is the listening state then this 5613 * packet is a SYN-ACK packet which means it needs to 5614 * be labeled based on the connection/request_sock and 5615 * not the parent socket. unfortunately, we can't 5616 * lookup the request_sock yet as it isn't queued on 5617 * the parent socket until after the SYN-ACK is sent. 5618 * the "solution" is to simply pass the packet as-is 5619 * as any IP option based labeling should be copied 5620 * from the initial connection request (in the IP 5621 * layer). it is far from ideal, but until we get a 5622 * security label in the packet itself this is the 5623 * best we can do. */ 5624 return NF_ACCEPT; 5625 5626 /* standard practice, label using the parent socket */ 5627 sksec = sk->sk_security; 5628 sid = sksec->sid; 5629 } else 5630 sid = SECINITSID_KERNEL; 5631 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5632 return NF_DROP; 5633 5634 return NF_ACCEPT; 5635 } 5636 5637 static unsigned int selinux_ipv4_output(void *priv, 5638 struct sk_buff *skb, 5639 const struct nf_hook_state *state) 5640 { 5641 return selinux_ip_output(skb, PF_INET); 5642 } 5643 5644 #if IS_ENABLED(CONFIG_IPV6) 5645 static unsigned int selinux_ipv6_output(void *priv, 5646 struct sk_buff *skb, 5647 const struct nf_hook_state *state) 5648 { 5649 return selinux_ip_output(skb, PF_INET6); 5650 } 5651 #endif /* IPV6 */ 5652 5653 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5654 int ifindex, 5655 u16 family) 5656 { 5657 struct sock *sk = skb_to_full_sk(skb); 5658 struct sk_security_struct *sksec; 5659 struct common_audit_data ad; 5660 struct lsm_network_audit net = {0,}; 5661 char *addrp; 5662 u8 proto; 5663 5664 if (sk == NULL) 5665 return NF_ACCEPT; 5666 sksec = sk->sk_security; 5667 5668 ad.type = LSM_AUDIT_DATA_NET; 5669 ad.u.net = &net; 5670 ad.u.net->netif = ifindex; 5671 ad.u.net->family = family; 5672 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5673 return NF_DROP; 5674 5675 if (selinux_secmark_enabled()) 5676 if (avc_has_perm(&selinux_state, 5677 sksec->sid, skb->secmark, 5678 SECCLASS_PACKET, PACKET__SEND, &ad)) 5679 return NF_DROP_ERR(-ECONNREFUSED); 5680 5681 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5682 return NF_DROP_ERR(-ECONNREFUSED); 5683 5684 return NF_ACCEPT; 5685 } 5686 5687 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5688 const struct net_device *outdev, 5689 u16 family) 5690 { 5691 u32 secmark_perm; 5692 u32 peer_sid; 5693 int ifindex = outdev->ifindex; 5694 struct sock *sk; 5695 struct common_audit_data ad; 5696 struct lsm_network_audit net = {0,}; 5697 char *addrp; 5698 u8 secmark_active; 5699 u8 peerlbl_active; 5700 5701 /* If any sort of compatibility mode is enabled then handoff processing 5702 * to the selinux_ip_postroute_compat() function to deal with the 5703 * special handling. We do this in an attempt to keep this function 5704 * as fast and as clean as possible. */ 5705 if (!selinux_policycap_netpeer()) 5706 return selinux_ip_postroute_compat(skb, ifindex, family); 5707 5708 secmark_active = selinux_secmark_enabled(); 5709 peerlbl_active = selinux_peerlbl_enabled(); 5710 if (!secmark_active && !peerlbl_active) 5711 return NF_ACCEPT; 5712 5713 sk = skb_to_full_sk(skb); 5714 5715 #ifdef CONFIG_XFRM 5716 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5717 * packet transformation so allow the packet to pass without any checks 5718 * since we'll have another chance to perform access control checks 5719 * when the packet is on it's final way out. 5720 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5721 * is NULL, in this case go ahead and apply access control. 5722 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5723 * TCP listening state we cannot wait until the XFRM processing 5724 * is done as we will miss out on the SA label if we do; 5725 * unfortunately, this means more work, but it is only once per 5726 * connection. */ 5727 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5728 !(sk && sk_listener(sk))) 5729 return NF_ACCEPT; 5730 #endif 5731 5732 if (sk == NULL) { 5733 /* Without an associated socket the packet is either coming 5734 * from the kernel or it is being forwarded; check the packet 5735 * to determine which and if the packet is being forwarded 5736 * query the packet directly to determine the security label. */ 5737 if (skb->skb_iif) { 5738 secmark_perm = PACKET__FORWARD_OUT; 5739 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5740 return NF_DROP; 5741 } else { 5742 secmark_perm = PACKET__SEND; 5743 peer_sid = SECINITSID_KERNEL; 5744 } 5745 } else if (sk_listener(sk)) { 5746 /* Locally generated packet but the associated socket is in the 5747 * listening state which means this is a SYN-ACK packet. In 5748 * this particular case the correct security label is assigned 5749 * to the connection/request_sock but unfortunately we can't 5750 * query the request_sock as it isn't queued on the parent 5751 * socket until after the SYN-ACK packet is sent; the only 5752 * viable choice is to regenerate the label like we do in 5753 * selinux_inet_conn_request(). See also selinux_ip_output() 5754 * for similar problems. */ 5755 u32 skb_sid; 5756 struct sk_security_struct *sksec; 5757 5758 sksec = sk->sk_security; 5759 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5760 return NF_DROP; 5761 /* At this point, if the returned skb peerlbl is SECSID_NULL 5762 * and the packet has been through at least one XFRM 5763 * transformation then we must be dealing with the "final" 5764 * form of labeled IPsec packet; since we've already applied 5765 * all of our access controls on this packet we can safely 5766 * pass the packet. */ 5767 if (skb_sid == SECSID_NULL) { 5768 switch (family) { 5769 case PF_INET: 5770 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5771 return NF_ACCEPT; 5772 break; 5773 case PF_INET6: 5774 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5775 return NF_ACCEPT; 5776 break; 5777 default: 5778 return NF_DROP_ERR(-ECONNREFUSED); 5779 } 5780 } 5781 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5782 return NF_DROP; 5783 secmark_perm = PACKET__SEND; 5784 } else { 5785 /* Locally generated packet, fetch the security label from the 5786 * associated socket. */ 5787 struct sk_security_struct *sksec = sk->sk_security; 5788 peer_sid = sksec->sid; 5789 secmark_perm = PACKET__SEND; 5790 } 5791 5792 ad.type = LSM_AUDIT_DATA_NET; 5793 ad.u.net = &net; 5794 ad.u.net->netif = ifindex; 5795 ad.u.net->family = family; 5796 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5797 return NF_DROP; 5798 5799 if (secmark_active) 5800 if (avc_has_perm(&selinux_state, 5801 peer_sid, skb->secmark, 5802 SECCLASS_PACKET, secmark_perm, &ad)) 5803 return NF_DROP_ERR(-ECONNREFUSED); 5804 5805 if (peerlbl_active) { 5806 u32 if_sid; 5807 u32 node_sid; 5808 5809 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5810 return NF_DROP; 5811 if (avc_has_perm(&selinux_state, 5812 peer_sid, if_sid, 5813 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5814 return NF_DROP_ERR(-ECONNREFUSED); 5815 5816 if (sel_netnode_sid(addrp, family, &node_sid)) 5817 return NF_DROP; 5818 if (avc_has_perm(&selinux_state, 5819 peer_sid, node_sid, 5820 SECCLASS_NODE, NODE__SENDTO, &ad)) 5821 return NF_DROP_ERR(-ECONNREFUSED); 5822 } 5823 5824 return NF_ACCEPT; 5825 } 5826 5827 static unsigned int selinux_ipv4_postroute(void *priv, 5828 struct sk_buff *skb, 5829 const struct nf_hook_state *state) 5830 { 5831 return selinux_ip_postroute(skb, state->out, PF_INET); 5832 } 5833 5834 #if IS_ENABLED(CONFIG_IPV6) 5835 static unsigned int selinux_ipv6_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_INET6); 5840 } 5841 #endif /* IPV6 */ 5842 5843 #endif /* CONFIG_NETFILTER */ 5844 5845 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5846 { 5847 int rc = 0; 5848 unsigned int msg_len; 5849 unsigned int data_len = skb->len; 5850 unsigned char *data = skb->data; 5851 struct nlmsghdr *nlh; 5852 struct sk_security_struct *sksec = sk->sk_security; 5853 u16 sclass = sksec->sclass; 5854 u32 perm; 5855 5856 while (data_len >= nlmsg_total_size(0)) { 5857 nlh = (struct nlmsghdr *)data; 5858 5859 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5860 * users which means we can't reject skb's with bogus 5861 * length fields; our solution is to follow what 5862 * netlink_rcv_skb() does and simply skip processing at 5863 * messages with length fields that are clearly junk 5864 */ 5865 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5866 return 0; 5867 5868 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5869 if (rc == 0) { 5870 rc = sock_has_perm(sk, perm); 5871 if (rc) 5872 return rc; 5873 } else if (rc == -EINVAL) { 5874 /* -EINVAL is a missing msg/perm mapping */ 5875 pr_warn_ratelimited("SELinux: unrecognized netlink" 5876 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5877 " pid=%d comm=%s\n", 5878 sk->sk_protocol, nlh->nlmsg_type, 5879 secclass_map[sclass - 1].name, 5880 task_pid_nr(current), current->comm); 5881 if (enforcing_enabled(&selinux_state) && 5882 !security_get_allow_unknown(&selinux_state)) 5883 return rc; 5884 rc = 0; 5885 } else if (rc == -ENOENT) { 5886 /* -ENOENT is a missing socket/class mapping, ignore */ 5887 rc = 0; 5888 } else { 5889 return rc; 5890 } 5891 5892 /* move to the next message after applying netlink padding */ 5893 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5894 if (msg_len >= data_len) 5895 return 0; 5896 data_len -= msg_len; 5897 data += msg_len; 5898 } 5899 5900 return rc; 5901 } 5902 5903 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5904 { 5905 isec->sclass = sclass; 5906 isec->sid = current_sid(); 5907 } 5908 5909 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5910 u32 perms) 5911 { 5912 struct ipc_security_struct *isec; 5913 struct common_audit_data ad; 5914 u32 sid = current_sid(); 5915 5916 isec = selinux_ipc(ipc_perms); 5917 5918 ad.type = LSM_AUDIT_DATA_IPC; 5919 ad.u.ipc_id = ipc_perms->key; 5920 5921 return avc_has_perm(&selinux_state, 5922 sid, isec->sid, isec->sclass, perms, &ad); 5923 } 5924 5925 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5926 { 5927 struct msg_security_struct *msec; 5928 5929 msec = selinux_msg_msg(msg); 5930 msec->sid = SECINITSID_UNLABELED; 5931 5932 return 0; 5933 } 5934 5935 /* message queue security operations */ 5936 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5937 { 5938 struct ipc_security_struct *isec; 5939 struct common_audit_data ad; 5940 u32 sid = current_sid(); 5941 int rc; 5942 5943 isec = selinux_ipc(msq); 5944 ipc_init_security(isec, SECCLASS_MSGQ); 5945 5946 ad.type = LSM_AUDIT_DATA_IPC; 5947 ad.u.ipc_id = msq->key; 5948 5949 rc = avc_has_perm(&selinux_state, 5950 sid, isec->sid, SECCLASS_MSGQ, 5951 MSGQ__CREATE, &ad); 5952 return rc; 5953 } 5954 5955 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 5956 { 5957 struct ipc_security_struct *isec; 5958 struct common_audit_data ad; 5959 u32 sid = current_sid(); 5960 5961 isec = selinux_ipc(msq); 5962 5963 ad.type = LSM_AUDIT_DATA_IPC; 5964 ad.u.ipc_id = msq->key; 5965 5966 return avc_has_perm(&selinux_state, 5967 sid, isec->sid, SECCLASS_MSGQ, 5968 MSGQ__ASSOCIATE, &ad); 5969 } 5970 5971 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 5972 { 5973 int err; 5974 int perms; 5975 5976 switch (cmd) { 5977 case IPC_INFO: 5978 case MSG_INFO: 5979 /* No specific object, just general system-wide information. */ 5980 return avc_has_perm(&selinux_state, 5981 current_sid(), SECINITSID_KERNEL, 5982 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 5983 case IPC_STAT: 5984 case MSG_STAT: 5985 case MSG_STAT_ANY: 5986 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 5987 break; 5988 case IPC_SET: 5989 perms = MSGQ__SETATTR; 5990 break; 5991 case IPC_RMID: 5992 perms = MSGQ__DESTROY; 5993 break; 5994 default: 5995 return 0; 5996 } 5997 5998 err = ipc_has_perm(msq, perms); 5999 return err; 6000 } 6001 6002 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6003 { 6004 struct ipc_security_struct *isec; 6005 struct msg_security_struct *msec; 6006 struct common_audit_data ad; 6007 u32 sid = current_sid(); 6008 int rc; 6009 6010 isec = selinux_ipc(msq); 6011 msec = selinux_msg_msg(msg); 6012 6013 /* 6014 * First time through, need to assign label to the message 6015 */ 6016 if (msec->sid == SECINITSID_UNLABELED) { 6017 /* 6018 * Compute new sid based on current process and 6019 * message queue this message will be stored in 6020 */ 6021 rc = security_transition_sid(&selinux_state, sid, isec->sid, 6022 SECCLASS_MSG, NULL, &msec->sid); 6023 if (rc) 6024 return rc; 6025 } 6026 6027 ad.type = LSM_AUDIT_DATA_IPC; 6028 ad.u.ipc_id = msq->key; 6029 6030 /* Can this process write to the queue? */ 6031 rc = avc_has_perm(&selinux_state, 6032 sid, isec->sid, SECCLASS_MSGQ, 6033 MSGQ__WRITE, &ad); 6034 if (!rc) 6035 /* Can this process send the message */ 6036 rc = avc_has_perm(&selinux_state, 6037 sid, msec->sid, SECCLASS_MSG, 6038 MSG__SEND, &ad); 6039 if (!rc) 6040 /* Can the message be put in the queue? */ 6041 rc = avc_has_perm(&selinux_state, 6042 msec->sid, isec->sid, SECCLASS_MSGQ, 6043 MSGQ__ENQUEUE, &ad); 6044 6045 return rc; 6046 } 6047 6048 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6049 struct task_struct *target, 6050 long type, int mode) 6051 { 6052 struct ipc_security_struct *isec; 6053 struct msg_security_struct *msec; 6054 struct common_audit_data ad; 6055 u32 sid = task_sid(target); 6056 int rc; 6057 6058 isec = selinux_ipc(msq); 6059 msec = selinux_msg_msg(msg); 6060 6061 ad.type = LSM_AUDIT_DATA_IPC; 6062 ad.u.ipc_id = msq->key; 6063 6064 rc = avc_has_perm(&selinux_state, 6065 sid, isec->sid, 6066 SECCLASS_MSGQ, MSGQ__READ, &ad); 6067 if (!rc) 6068 rc = avc_has_perm(&selinux_state, 6069 sid, msec->sid, 6070 SECCLASS_MSG, MSG__RECEIVE, &ad); 6071 return rc; 6072 } 6073 6074 /* Shared Memory security operations */ 6075 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6076 { 6077 struct ipc_security_struct *isec; 6078 struct common_audit_data ad; 6079 u32 sid = current_sid(); 6080 int rc; 6081 6082 isec = selinux_ipc(shp); 6083 ipc_init_security(isec, SECCLASS_SHM); 6084 6085 ad.type = LSM_AUDIT_DATA_IPC; 6086 ad.u.ipc_id = shp->key; 6087 6088 rc = avc_has_perm(&selinux_state, 6089 sid, isec->sid, SECCLASS_SHM, 6090 SHM__CREATE, &ad); 6091 return rc; 6092 } 6093 6094 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6095 { 6096 struct ipc_security_struct *isec; 6097 struct common_audit_data ad; 6098 u32 sid = current_sid(); 6099 6100 isec = selinux_ipc(shp); 6101 6102 ad.type = LSM_AUDIT_DATA_IPC; 6103 ad.u.ipc_id = shp->key; 6104 6105 return avc_has_perm(&selinux_state, 6106 sid, isec->sid, SECCLASS_SHM, 6107 SHM__ASSOCIATE, &ad); 6108 } 6109 6110 /* Note, at this point, shp is locked down */ 6111 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6112 { 6113 int perms; 6114 int err; 6115 6116 switch (cmd) { 6117 case IPC_INFO: 6118 case SHM_INFO: 6119 /* No specific object, just general system-wide information. */ 6120 return avc_has_perm(&selinux_state, 6121 current_sid(), SECINITSID_KERNEL, 6122 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6123 case IPC_STAT: 6124 case SHM_STAT: 6125 case SHM_STAT_ANY: 6126 perms = SHM__GETATTR | SHM__ASSOCIATE; 6127 break; 6128 case IPC_SET: 6129 perms = SHM__SETATTR; 6130 break; 6131 case SHM_LOCK: 6132 case SHM_UNLOCK: 6133 perms = SHM__LOCK; 6134 break; 6135 case IPC_RMID: 6136 perms = SHM__DESTROY; 6137 break; 6138 default: 6139 return 0; 6140 } 6141 6142 err = ipc_has_perm(shp, perms); 6143 return err; 6144 } 6145 6146 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6147 char __user *shmaddr, int shmflg) 6148 { 6149 u32 perms; 6150 6151 if (shmflg & SHM_RDONLY) 6152 perms = SHM__READ; 6153 else 6154 perms = SHM__READ | SHM__WRITE; 6155 6156 return ipc_has_perm(shp, perms); 6157 } 6158 6159 /* Semaphore security operations */ 6160 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6161 { 6162 struct ipc_security_struct *isec; 6163 struct common_audit_data ad; 6164 u32 sid = current_sid(); 6165 int rc; 6166 6167 isec = selinux_ipc(sma); 6168 ipc_init_security(isec, SECCLASS_SEM); 6169 6170 ad.type = LSM_AUDIT_DATA_IPC; 6171 ad.u.ipc_id = sma->key; 6172 6173 rc = avc_has_perm(&selinux_state, 6174 sid, isec->sid, SECCLASS_SEM, 6175 SEM__CREATE, &ad); 6176 return rc; 6177 } 6178 6179 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6180 { 6181 struct ipc_security_struct *isec; 6182 struct common_audit_data ad; 6183 u32 sid = current_sid(); 6184 6185 isec = selinux_ipc(sma); 6186 6187 ad.type = LSM_AUDIT_DATA_IPC; 6188 ad.u.ipc_id = sma->key; 6189 6190 return avc_has_perm(&selinux_state, 6191 sid, isec->sid, SECCLASS_SEM, 6192 SEM__ASSOCIATE, &ad); 6193 } 6194 6195 /* Note, at this point, sma is locked down */ 6196 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6197 { 6198 int err; 6199 u32 perms; 6200 6201 switch (cmd) { 6202 case IPC_INFO: 6203 case SEM_INFO: 6204 /* No specific object, just general system-wide information. */ 6205 return avc_has_perm(&selinux_state, 6206 current_sid(), SECINITSID_KERNEL, 6207 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6208 case GETPID: 6209 case GETNCNT: 6210 case GETZCNT: 6211 perms = SEM__GETATTR; 6212 break; 6213 case GETVAL: 6214 case GETALL: 6215 perms = SEM__READ; 6216 break; 6217 case SETVAL: 6218 case SETALL: 6219 perms = SEM__WRITE; 6220 break; 6221 case IPC_RMID: 6222 perms = SEM__DESTROY; 6223 break; 6224 case IPC_SET: 6225 perms = SEM__SETATTR; 6226 break; 6227 case IPC_STAT: 6228 case SEM_STAT: 6229 case SEM_STAT_ANY: 6230 perms = SEM__GETATTR | SEM__ASSOCIATE; 6231 break; 6232 default: 6233 return 0; 6234 } 6235 6236 err = ipc_has_perm(sma, perms); 6237 return err; 6238 } 6239 6240 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6241 struct sembuf *sops, unsigned nsops, int alter) 6242 { 6243 u32 perms; 6244 6245 if (alter) 6246 perms = SEM__READ | SEM__WRITE; 6247 else 6248 perms = SEM__READ; 6249 6250 return ipc_has_perm(sma, perms); 6251 } 6252 6253 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6254 { 6255 u32 av = 0; 6256 6257 av = 0; 6258 if (flag & S_IRUGO) 6259 av |= IPC__UNIX_READ; 6260 if (flag & S_IWUGO) 6261 av |= IPC__UNIX_WRITE; 6262 6263 if (av == 0) 6264 return 0; 6265 6266 return ipc_has_perm(ipcp, av); 6267 } 6268 6269 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6270 { 6271 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6272 *secid = isec->sid; 6273 } 6274 6275 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6276 { 6277 if (inode) 6278 inode_doinit_with_dentry(inode, dentry); 6279 } 6280 6281 static int selinux_getprocattr(struct task_struct *p, 6282 char *name, char **value) 6283 { 6284 const struct task_security_struct *__tsec; 6285 u32 sid; 6286 int error; 6287 unsigned len; 6288 6289 rcu_read_lock(); 6290 __tsec = selinux_cred(__task_cred(p)); 6291 6292 if (current != p) { 6293 error = avc_has_perm(&selinux_state, 6294 current_sid(), __tsec->sid, 6295 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6296 if (error) 6297 goto bad; 6298 } 6299 6300 if (!strcmp(name, "current")) 6301 sid = __tsec->sid; 6302 else if (!strcmp(name, "prev")) 6303 sid = __tsec->osid; 6304 else if (!strcmp(name, "exec")) 6305 sid = __tsec->exec_sid; 6306 else if (!strcmp(name, "fscreate")) 6307 sid = __tsec->create_sid; 6308 else if (!strcmp(name, "keycreate")) 6309 sid = __tsec->keycreate_sid; 6310 else if (!strcmp(name, "sockcreate")) 6311 sid = __tsec->sockcreate_sid; 6312 else { 6313 error = -EINVAL; 6314 goto bad; 6315 } 6316 rcu_read_unlock(); 6317 6318 if (!sid) 6319 return 0; 6320 6321 error = security_sid_to_context(&selinux_state, sid, value, &len); 6322 if (error) 6323 return error; 6324 return len; 6325 6326 bad: 6327 rcu_read_unlock(); 6328 return error; 6329 } 6330 6331 static int selinux_setprocattr(const char *name, void *value, size_t size) 6332 { 6333 struct task_security_struct *tsec; 6334 struct cred *new; 6335 u32 mysid = current_sid(), sid = 0, ptsid; 6336 int error; 6337 char *str = value; 6338 6339 /* 6340 * Basic control over ability to set these attributes at all. 6341 */ 6342 if (!strcmp(name, "exec")) 6343 error = avc_has_perm(&selinux_state, 6344 mysid, mysid, SECCLASS_PROCESS, 6345 PROCESS__SETEXEC, NULL); 6346 else if (!strcmp(name, "fscreate")) 6347 error = avc_has_perm(&selinux_state, 6348 mysid, mysid, SECCLASS_PROCESS, 6349 PROCESS__SETFSCREATE, NULL); 6350 else if (!strcmp(name, "keycreate")) 6351 error = avc_has_perm(&selinux_state, 6352 mysid, mysid, SECCLASS_PROCESS, 6353 PROCESS__SETKEYCREATE, NULL); 6354 else if (!strcmp(name, "sockcreate")) 6355 error = avc_has_perm(&selinux_state, 6356 mysid, mysid, SECCLASS_PROCESS, 6357 PROCESS__SETSOCKCREATE, NULL); 6358 else if (!strcmp(name, "current")) 6359 error = avc_has_perm(&selinux_state, 6360 mysid, mysid, SECCLASS_PROCESS, 6361 PROCESS__SETCURRENT, NULL); 6362 else 6363 error = -EINVAL; 6364 if (error) 6365 return error; 6366 6367 /* Obtain a SID for the context, if one was specified. */ 6368 if (size && str[0] && str[0] != '\n') { 6369 if (str[size-1] == '\n') { 6370 str[size-1] = 0; 6371 size--; 6372 } 6373 error = security_context_to_sid(&selinux_state, value, size, 6374 &sid, GFP_KERNEL); 6375 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6376 if (!has_cap_mac_admin(true)) { 6377 struct audit_buffer *ab; 6378 size_t audit_size; 6379 6380 /* We strip a nul only if it is at the end, otherwise the 6381 * context contains a nul and we should audit that */ 6382 if (str[size - 1] == '\0') 6383 audit_size = size - 1; 6384 else 6385 audit_size = size; 6386 ab = audit_log_start(audit_context(), 6387 GFP_ATOMIC, 6388 AUDIT_SELINUX_ERR); 6389 audit_log_format(ab, "op=fscreate invalid_context="); 6390 audit_log_n_untrustedstring(ab, value, audit_size); 6391 audit_log_end(ab); 6392 6393 return error; 6394 } 6395 error = security_context_to_sid_force( 6396 &selinux_state, 6397 value, size, &sid); 6398 } 6399 if (error) 6400 return error; 6401 } 6402 6403 new = prepare_creds(); 6404 if (!new) 6405 return -ENOMEM; 6406 6407 /* Permission checking based on the specified context is 6408 performed during the actual operation (execve, 6409 open/mkdir/...), when we know the full context of the 6410 operation. See selinux_bprm_creds_for_exec for the execve 6411 checks and may_create for the file creation checks. The 6412 operation will then fail if the context is not permitted. */ 6413 tsec = selinux_cred(new); 6414 if (!strcmp(name, "exec")) { 6415 tsec->exec_sid = sid; 6416 } else if (!strcmp(name, "fscreate")) { 6417 tsec->create_sid = sid; 6418 } else if (!strcmp(name, "keycreate")) { 6419 if (sid) { 6420 error = avc_has_perm(&selinux_state, mysid, sid, 6421 SECCLASS_KEY, KEY__CREATE, NULL); 6422 if (error) 6423 goto abort_change; 6424 } 6425 tsec->keycreate_sid = sid; 6426 } else if (!strcmp(name, "sockcreate")) { 6427 tsec->sockcreate_sid = sid; 6428 } else if (!strcmp(name, "current")) { 6429 error = -EINVAL; 6430 if (sid == 0) 6431 goto abort_change; 6432 6433 /* Only allow single threaded processes to change context */ 6434 error = -EPERM; 6435 if (!current_is_single_threaded()) { 6436 error = security_bounded_transition(&selinux_state, 6437 tsec->sid, sid); 6438 if (error) 6439 goto abort_change; 6440 } 6441 6442 /* Check permissions for the transition. */ 6443 error = avc_has_perm(&selinux_state, 6444 tsec->sid, sid, SECCLASS_PROCESS, 6445 PROCESS__DYNTRANSITION, NULL); 6446 if (error) 6447 goto abort_change; 6448 6449 /* Check for ptracing, and update the task SID if ok. 6450 Otherwise, leave SID unchanged and fail. */ 6451 ptsid = ptrace_parent_sid(); 6452 if (ptsid != 0) { 6453 error = avc_has_perm(&selinux_state, 6454 ptsid, sid, SECCLASS_PROCESS, 6455 PROCESS__PTRACE, NULL); 6456 if (error) 6457 goto abort_change; 6458 } 6459 6460 tsec->sid = sid; 6461 } else { 6462 error = -EINVAL; 6463 goto abort_change; 6464 } 6465 6466 commit_creds(new); 6467 return size; 6468 6469 abort_change: 6470 abort_creds(new); 6471 return error; 6472 } 6473 6474 static int selinux_ismaclabel(const char *name) 6475 { 6476 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6477 } 6478 6479 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6480 { 6481 return security_sid_to_context(&selinux_state, secid, 6482 secdata, seclen); 6483 } 6484 6485 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6486 { 6487 return security_context_to_sid(&selinux_state, secdata, seclen, 6488 secid, GFP_KERNEL); 6489 } 6490 6491 static void selinux_release_secctx(char *secdata, u32 seclen) 6492 { 6493 kfree(secdata); 6494 } 6495 6496 static void selinux_inode_invalidate_secctx(struct inode *inode) 6497 { 6498 struct inode_security_struct *isec = selinux_inode(inode); 6499 6500 spin_lock(&isec->lock); 6501 isec->initialized = LABEL_INVALID; 6502 spin_unlock(&isec->lock); 6503 } 6504 6505 /* 6506 * called with inode->i_mutex locked 6507 */ 6508 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6509 { 6510 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6511 ctx, ctxlen, 0); 6512 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6513 return rc == -EOPNOTSUPP ? 0 : rc; 6514 } 6515 6516 /* 6517 * called with inode->i_mutex locked 6518 */ 6519 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6520 { 6521 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 6522 } 6523 6524 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6525 { 6526 int len = 0; 6527 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 6528 ctx, true); 6529 if (len < 0) 6530 return len; 6531 *ctxlen = len; 6532 return 0; 6533 } 6534 #ifdef CONFIG_KEYS 6535 6536 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6537 unsigned long flags) 6538 { 6539 const struct task_security_struct *tsec; 6540 struct key_security_struct *ksec; 6541 6542 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6543 if (!ksec) 6544 return -ENOMEM; 6545 6546 tsec = selinux_cred(cred); 6547 if (tsec->keycreate_sid) 6548 ksec->sid = tsec->keycreate_sid; 6549 else 6550 ksec->sid = tsec->sid; 6551 6552 k->security = ksec; 6553 return 0; 6554 } 6555 6556 static void selinux_key_free(struct key *k) 6557 { 6558 struct key_security_struct *ksec = k->security; 6559 6560 k->security = NULL; 6561 kfree(ksec); 6562 } 6563 6564 static int selinux_key_permission(key_ref_t key_ref, 6565 const struct cred *cred, 6566 enum key_need_perm need_perm) 6567 { 6568 struct key *key; 6569 struct key_security_struct *ksec; 6570 u32 perm, sid; 6571 6572 switch (need_perm) { 6573 case KEY_NEED_VIEW: 6574 perm = KEY__VIEW; 6575 break; 6576 case KEY_NEED_READ: 6577 perm = KEY__READ; 6578 break; 6579 case KEY_NEED_WRITE: 6580 perm = KEY__WRITE; 6581 break; 6582 case KEY_NEED_SEARCH: 6583 perm = KEY__SEARCH; 6584 break; 6585 case KEY_NEED_LINK: 6586 perm = KEY__LINK; 6587 break; 6588 case KEY_NEED_SETATTR: 6589 perm = KEY__SETATTR; 6590 break; 6591 case KEY_NEED_UNLINK: 6592 case KEY_SYSADMIN_OVERRIDE: 6593 case KEY_AUTHTOKEN_OVERRIDE: 6594 case KEY_DEFER_PERM_CHECK: 6595 return 0; 6596 default: 6597 WARN_ON(1); 6598 return -EPERM; 6599 6600 } 6601 6602 sid = cred_sid(cred); 6603 key = key_ref_to_ptr(key_ref); 6604 ksec = key->security; 6605 6606 return avc_has_perm(&selinux_state, 6607 sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6608 } 6609 6610 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6611 { 6612 struct key_security_struct *ksec = key->security; 6613 char *context = NULL; 6614 unsigned len; 6615 int rc; 6616 6617 rc = security_sid_to_context(&selinux_state, ksec->sid, 6618 &context, &len); 6619 if (!rc) 6620 rc = len; 6621 *_buffer = context; 6622 return rc; 6623 } 6624 6625 #ifdef CONFIG_KEY_NOTIFICATIONS 6626 static int selinux_watch_key(struct key *key) 6627 { 6628 struct key_security_struct *ksec = key->security; 6629 u32 sid = current_sid(); 6630 6631 return avc_has_perm(&selinux_state, 6632 sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6633 } 6634 #endif 6635 #endif 6636 6637 #ifdef CONFIG_SECURITY_INFINIBAND 6638 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6639 { 6640 struct common_audit_data ad; 6641 int err; 6642 u32 sid = 0; 6643 struct ib_security_struct *sec = ib_sec; 6644 struct lsm_ibpkey_audit ibpkey; 6645 6646 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6647 if (err) 6648 return err; 6649 6650 ad.type = LSM_AUDIT_DATA_IBPKEY; 6651 ibpkey.subnet_prefix = subnet_prefix; 6652 ibpkey.pkey = pkey_val; 6653 ad.u.ibpkey = &ibpkey; 6654 return avc_has_perm(&selinux_state, 6655 sec->sid, sid, 6656 SECCLASS_INFINIBAND_PKEY, 6657 INFINIBAND_PKEY__ACCESS, &ad); 6658 } 6659 6660 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6661 u8 port_num) 6662 { 6663 struct common_audit_data ad; 6664 int err; 6665 u32 sid = 0; 6666 struct ib_security_struct *sec = ib_sec; 6667 struct lsm_ibendport_audit ibendport; 6668 6669 err = security_ib_endport_sid(&selinux_state, dev_name, port_num, 6670 &sid); 6671 6672 if (err) 6673 return err; 6674 6675 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6676 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name)); 6677 ibendport.port = port_num; 6678 ad.u.ibendport = &ibendport; 6679 return avc_has_perm(&selinux_state, 6680 sec->sid, sid, 6681 SECCLASS_INFINIBAND_ENDPORT, 6682 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6683 } 6684 6685 static int selinux_ib_alloc_security(void **ib_sec) 6686 { 6687 struct ib_security_struct *sec; 6688 6689 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6690 if (!sec) 6691 return -ENOMEM; 6692 sec->sid = current_sid(); 6693 6694 *ib_sec = sec; 6695 return 0; 6696 } 6697 6698 static void selinux_ib_free_security(void *ib_sec) 6699 { 6700 kfree(ib_sec); 6701 } 6702 #endif 6703 6704 #ifdef CONFIG_BPF_SYSCALL 6705 static int selinux_bpf(int cmd, union bpf_attr *attr, 6706 unsigned int size) 6707 { 6708 u32 sid = current_sid(); 6709 int ret; 6710 6711 switch (cmd) { 6712 case BPF_MAP_CREATE: 6713 ret = avc_has_perm(&selinux_state, 6714 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6715 NULL); 6716 break; 6717 case BPF_PROG_LOAD: 6718 ret = avc_has_perm(&selinux_state, 6719 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6720 NULL); 6721 break; 6722 default: 6723 ret = 0; 6724 break; 6725 } 6726 6727 return ret; 6728 } 6729 6730 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6731 { 6732 u32 av = 0; 6733 6734 if (fmode & FMODE_READ) 6735 av |= BPF__MAP_READ; 6736 if (fmode & FMODE_WRITE) 6737 av |= BPF__MAP_WRITE; 6738 return av; 6739 } 6740 6741 /* This function will check the file pass through unix socket or binder to see 6742 * if it is a bpf related object. And apply correspinding checks on the bpf 6743 * object based on the type. The bpf maps and programs, not like other files and 6744 * socket, are using a shared anonymous inode inside the kernel as their inode. 6745 * So checking that inode cannot identify if the process have privilege to 6746 * access the bpf object and that's why we have to add this additional check in 6747 * selinux_file_receive and selinux_binder_transfer_files. 6748 */ 6749 static int bpf_fd_pass(struct file *file, u32 sid) 6750 { 6751 struct bpf_security_struct *bpfsec; 6752 struct bpf_prog *prog; 6753 struct bpf_map *map; 6754 int ret; 6755 6756 if (file->f_op == &bpf_map_fops) { 6757 map = file->private_data; 6758 bpfsec = map->security; 6759 ret = avc_has_perm(&selinux_state, 6760 sid, bpfsec->sid, SECCLASS_BPF, 6761 bpf_map_fmode_to_av(file->f_mode), NULL); 6762 if (ret) 6763 return ret; 6764 } else if (file->f_op == &bpf_prog_fops) { 6765 prog = file->private_data; 6766 bpfsec = prog->aux->security; 6767 ret = avc_has_perm(&selinux_state, 6768 sid, bpfsec->sid, SECCLASS_BPF, 6769 BPF__PROG_RUN, NULL); 6770 if (ret) 6771 return ret; 6772 } 6773 return 0; 6774 } 6775 6776 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6777 { 6778 u32 sid = current_sid(); 6779 struct bpf_security_struct *bpfsec; 6780 6781 bpfsec = map->security; 6782 return avc_has_perm(&selinux_state, 6783 sid, bpfsec->sid, SECCLASS_BPF, 6784 bpf_map_fmode_to_av(fmode), NULL); 6785 } 6786 6787 static int selinux_bpf_prog(struct bpf_prog *prog) 6788 { 6789 u32 sid = current_sid(); 6790 struct bpf_security_struct *bpfsec; 6791 6792 bpfsec = prog->aux->security; 6793 return avc_has_perm(&selinux_state, 6794 sid, bpfsec->sid, SECCLASS_BPF, 6795 BPF__PROG_RUN, NULL); 6796 } 6797 6798 static int selinux_bpf_map_alloc(struct bpf_map *map) 6799 { 6800 struct bpf_security_struct *bpfsec; 6801 6802 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6803 if (!bpfsec) 6804 return -ENOMEM; 6805 6806 bpfsec->sid = current_sid(); 6807 map->security = bpfsec; 6808 6809 return 0; 6810 } 6811 6812 static void selinux_bpf_map_free(struct bpf_map *map) 6813 { 6814 struct bpf_security_struct *bpfsec = map->security; 6815 6816 map->security = NULL; 6817 kfree(bpfsec); 6818 } 6819 6820 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6821 { 6822 struct bpf_security_struct *bpfsec; 6823 6824 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6825 if (!bpfsec) 6826 return -ENOMEM; 6827 6828 bpfsec->sid = current_sid(); 6829 aux->security = bpfsec; 6830 6831 return 0; 6832 } 6833 6834 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6835 { 6836 struct bpf_security_struct *bpfsec = aux->security; 6837 6838 aux->security = NULL; 6839 kfree(bpfsec); 6840 } 6841 #endif 6842 6843 static int selinux_lockdown(enum lockdown_reason what) 6844 { 6845 struct common_audit_data ad; 6846 u32 sid = current_sid(); 6847 int invalid_reason = (what <= LOCKDOWN_NONE) || 6848 (what == LOCKDOWN_INTEGRITY_MAX) || 6849 (what >= LOCKDOWN_CONFIDENTIALITY_MAX); 6850 6851 if (WARN(invalid_reason, "Invalid lockdown reason")) { 6852 audit_log(audit_context(), 6853 GFP_ATOMIC, AUDIT_SELINUX_ERR, 6854 "lockdown_reason=invalid"); 6855 return -EINVAL; 6856 } 6857 6858 ad.type = LSM_AUDIT_DATA_LOCKDOWN; 6859 ad.u.reason = what; 6860 6861 if (what <= LOCKDOWN_INTEGRITY_MAX) 6862 return avc_has_perm(&selinux_state, 6863 sid, sid, SECCLASS_LOCKDOWN, 6864 LOCKDOWN__INTEGRITY, &ad); 6865 else 6866 return avc_has_perm(&selinux_state, 6867 sid, sid, SECCLASS_LOCKDOWN, 6868 LOCKDOWN__CONFIDENTIALITY, &ad); 6869 } 6870 6871 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = { 6872 .lbs_cred = sizeof(struct task_security_struct), 6873 .lbs_file = sizeof(struct file_security_struct), 6874 .lbs_inode = sizeof(struct inode_security_struct), 6875 .lbs_ipc = sizeof(struct ipc_security_struct), 6876 .lbs_msg_msg = sizeof(struct msg_security_struct), 6877 }; 6878 6879 #ifdef CONFIG_PERF_EVENTS 6880 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6881 { 6882 u32 requested, sid = current_sid(); 6883 6884 if (type == PERF_SECURITY_OPEN) 6885 requested = PERF_EVENT__OPEN; 6886 else if (type == PERF_SECURITY_CPU) 6887 requested = PERF_EVENT__CPU; 6888 else if (type == PERF_SECURITY_KERNEL) 6889 requested = PERF_EVENT__KERNEL; 6890 else if (type == PERF_SECURITY_TRACEPOINT) 6891 requested = PERF_EVENT__TRACEPOINT; 6892 else 6893 return -EINVAL; 6894 6895 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT, 6896 requested, NULL); 6897 } 6898 6899 static int selinux_perf_event_alloc(struct perf_event *event) 6900 { 6901 struct perf_event_security_struct *perfsec; 6902 6903 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6904 if (!perfsec) 6905 return -ENOMEM; 6906 6907 perfsec->sid = current_sid(); 6908 event->security = perfsec; 6909 6910 return 0; 6911 } 6912 6913 static void selinux_perf_event_free(struct perf_event *event) 6914 { 6915 struct perf_event_security_struct *perfsec = event->security; 6916 6917 event->security = NULL; 6918 kfree(perfsec); 6919 } 6920 6921 static int selinux_perf_event_read(struct perf_event *event) 6922 { 6923 struct perf_event_security_struct *perfsec = event->security; 6924 u32 sid = current_sid(); 6925 6926 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6927 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6928 } 6929 6930 static int selinux_perf_event_write(struct perf_event *event) 6931 { 6932 struct perf_event_security_struct *perfsec = event->security; 6933 u32 sid = current_sid(); 6934 6935 return avc_has_perm(&selinux_state, sid, perfsec->sid, 6936 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6937 } 6938 #endif 6939 6940 /* 6941 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6942 * 1. any hooks that don't belong to (2.) or (3.) below, 6943 * 2. hooks that both access structures allocated by other hooks, and allocate 6944 * structures that can be later accessed by other hooks (mostly "cloning" 6945 * hooks), 6946 * 3. hooks that only allocate structures that can be later accessed by other 6947 * hooks ("allocating" hooks). 6948 * 6949 * Please follow block comment delimiters in the list to keep this order. 6950 * 6951 * This ordering is needed for SELinux runtime disable to work at least somewhat 6952 * safely. Breaking the ordering rules above might lead to NULL pointer derefs 6953 * when disabling SELinux at runtime. 6954 */ 6955 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { 6956 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6957 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6958 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6959 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6960 6961 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6962 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6963 LSM_HOOK_INIT(capget, selinux_capget), 6964 LSM_HOOK_INIT(capset, selinux_capset), 6965 LSM_HOOK_INIT(capable, selinux_capable), 6966 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6967 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6968 LSM_HOOK_INIT(syslog, selinux_syslog), 6969 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6970 6971 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6972 6973 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 6974 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6975 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6976 6977 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), 6978 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 6979 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6980 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6981 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6982 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6983 LSM_HOOK_INIT(sb_mount, selinux_mount), 6984 LSM_HOOK_INIT(sb_umount, selinux_umount), 6985 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6986 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6987 6988 LSM_HOOK_INIT(move_mount, selinux_move_mount), 6989 6990 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6991 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 6992 6993 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 6994 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 6995 LSM_HOOK_INIT(inode_create, selinux_inode_create), 6996 LSM_HOOK_INIT(inode_link, selinux_inode_link), 6997 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 6998 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 6999 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7000 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7001 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7002 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7003 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7004 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7005 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7006 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7007 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7008 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7009 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7010 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7011 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7012 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7013 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7014 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7015 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7016 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7017 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7018 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7019 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7020 7021 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7022 7023 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7024 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7025 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7026 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7027 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7028 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7029 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7030 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7031 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7032 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7033 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7034 7035 LSM_HOOK_INIT(file_open, selinux_file_open), 7036 7037 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7038 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7039 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7040 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7041 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7042 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7043 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7044 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7045 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7046 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7047 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7048 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7049 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), 7050 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7051 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7052 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7053 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7054 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7055 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7056 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7057 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7058 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7059 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7060 7061 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7062 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7063 7064 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7065 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7066 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7067 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7068 7069 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7070 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7071 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7072 7073 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7074 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7075 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7076 7077 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7078 7079 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7080 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7081 7082 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7083 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7084 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7085 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7086 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7087 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7088 7089 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7090 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7091 7092 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7093 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7094 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7095 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7096 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7097 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7098 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7099 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7100 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7101 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7102 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7103 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7104 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7105 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7106 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7107 LSM_HOOK_INIT(socket_getpeersec_stream, 7108 selinux_socket_getpeersec_stream), 7109 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7110 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7111 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7112 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7113 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7114 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7115 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7116 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7117 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7118 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7119 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7120 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7121 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7122 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7123 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7124 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7125 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7126 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7127 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7128 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7129 #ifdef CONFIG_SECURITY_INFINIBAND 7130 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7131 LSM_HOOK_INIT(ib_endport_manage_subnet, 7132 selinux_ib_endport_manage_subnet), 7133 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7134 #endif 7135 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7136 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7137 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7138 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7139 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7140 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7141 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7142 selinux_xfrm_state_pol_flow_match), 7143 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7144 #endif 7145 7146 #ifdef CONFIG_KEYS 7147 LSM_HOOK_INIT(key_free, selinux_key_free), 7148 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7149 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7150 #ifdef CONFIG_KEY_NOTIFICATIONS 7151 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7152 #endif 7153 #endif 7154 7155 #ifdef CONFIG_AUDIT 7156 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7157 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7158 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7159 #endif 7160 7161 #ifdef CONFIG_BPF_SYSCALL 7162 LSM_HOOK_INIT(bpf, selinux_bpf), 7163 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7164 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7165 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7166 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7167 #endif 7168 7169 #ifdef CONFIG_PERF_EVENTS 7170 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7171 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7172 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7173 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7174 #endif 7175 7176 LSM_HOOK_INIT(locked_down, selinux_lockdown), 7177 7178 /* 7179 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7180 */ 7181 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7182 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7183 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7184 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt), 7185 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7186 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7187 #endif 7188 7189 /* 7190 * PUT "ALLOCATING" HOOKS HERE 7191 */ 7192 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7193 LSM_HOOK_INIT(msg_queue_alloc_security, 7194 selinux_msg_queue_alloc_security), 7195 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7196 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7197 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7198 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7199 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7200 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7201 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7202 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7203 #ifdef CONFIG_SECURITY_INFINIBAND 7204 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7205 #endif 7206 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7207 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7208 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7209 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7210 selinux_xfrm_state_alloc_acquire), 7211 #endif 7212 #ifdef CONFIG_KEYS 7213 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7214 #endif 7215 #ifdef CONFIG_AUDIT 7216 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7217 #endif 7218 #ifdef CONFIG_BPF_SYSCALL 7219 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7220 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7221 #endif 7222 #ifdef CONFIG_PERF_EVENTS 7223 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7224 #endif 7225 }; 7226 7227 static __init int selinux_init(void) 7228 { 7229 pr_info("SELinux: Initializing.\n"); 7230 7231 memset(&selinux_state, 0, sizeof(selinux_state)); 7232 enforcing_set(&selinux_state, selinux_enforcing_boot); 7233 checkreqprot_set(&selinux_state, selinux_checkreqprot_boot); 7234 selinux_avc_init(&selinux_state.avc); 7235 mutex_init(&selinux_state.status_lock); 7236 mutex_init(&selinux_state.policy_mutex); 7237 7238 /* Set the security state for the initial task. */ 7239 cred_init_security(); 7240 7241 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7242 7243 avc_init(); 7244 7245 avtab_cache_init(); 7246 7247 ebitmap_cache_init(); 7248 7249 hashtab_cache_init(); 7250 7251 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7252 7253 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7254 panic("SELinux: Unable to register AVC netcache callback\n"); 7255 7256 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7257 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7258 7259 if (selinux_enforcing_boot) 7260 pr_debug("SELinux: Starting in enforcing mode\n"); 7261 else 7262 pr_debug("SELinux: Starting in permissive mode\n"); 7263 7264 fs_validate_description("selinux", selinux_fs_parameters); 7265 7266 return 0; 7267 } 7268 7269 static void delayed_superblock_init(struct super_block *sb, void *unused) 7270 { 7271 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7272 } 7273 7274 void selinux_complete_init(void) 7275 { 7276 pr_debug("SELinux: Completing initialization.\n"); 7277 7278 /* Set up any superblocks initialized prior to the policy load. */ 7279 pr_debug("SELinux: Setting up existing superblocks.\n"); 7280 iterate_supers(delayed_superblock_init, NULL); 7281 } 7282 7283 /* SELinux requires early initialization in order to label 7284 all processes and objects when they are created. */ 7285 DEFINE_LSM(selinux) = { 7286 .name = "selinux", 7287 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7288 .enabled = &selinux_enabled_boot, 7289 .blobs = &selinux_blob_sizes, 7290 .init = selinux_init, 7291 }; 7292 7293 #if defined(CONFIG_NETFILTER) 7294 7295 static const struct nf_hook_ops selinux_nf_ops[] = { 7296 { 7297 .hook = selinux_ipv4_postroute, 7298 .pf = NFPROTO_IPV4, 7299 .hooknum = NF_INET_POST_ROUTING, 7300 .priority = NF_IP_PRI_SELINUX_LAST, 7301 }, 7302 { 7303 .hook = selinux_ipv4_forward, 7304 .pf = NFPROTO_IPV4, 7305 .hooknum = NF_INET_FORWARD, 7306 .priority = NF_IP_PRI_SELINUX_FIRST, 7307 }, 7308 { 7309 .hook = selinux_ipv4_output, 7310 .pf = NFPROTO_IPV4, 7311 .hooknum = NF_INET_LOCAL_OUT, 7312 .priority = NF_IP_PRI_SELINUX_FIRST, 7313 }, 7314 #if IS_ENABLED(CONFIG_IPV6) 7315 { 7316 .hook = selinux_ipv6_postroute, 7317 .pf = NFPROTO_IPV6, 7318 .hooknum = NF_INET_POST_ROUTING, 7319 .priority = NF_IP6_PRI_SELINUX_LAST, 7320 }, 7321 { 7322 .hook = selinux_ipv6_forward, 7323 .pf = NFPROTO_IPV6, 7324 .hooknum = NF_INET_FORWARD, 7325 .priority = NF_IP6_PRI_SELINUX_FIRST, 7326 }, 7327 { 7328 .hook = selinux_ipv6_output, 7329 .pf = NFPROTO_IPV6, 7330 .hooknum = NF_INET_LOCAL_OUT, 7331 .priority = NF_IP6_PRI_SELINUX_FIRST, 7332 }, 7333 #endif /* IPV6 */ 7334 }; 7335 7336 static int __net_init selinux_nf_register(struct net *net) 7337 { 7338 return nf_register_net_hooks(net, selinux_nf_ops, 7339 ARRAY_SIZE(selinux_nf_ops)); 7340 } 7341 7342 static void __net_exit selinux_nf_unregister(struct net *net) 7343 { 7344 nf_unregister_net_hooks(net, selinux_nf_ops, 7345 ARRAY_SIZE(selinux_nf_ops)); 7346 } 7347 7348 static struct pernet_operations selinux_net_ops = { 7349 .init = selinux_nf_register, 7350 .exit = selinux_nf_unregister, 7351 }; 7352 7353 static int __init selinux_nf_ip_init(void) 7354 { 7355 int err; 7356 7357 if (!selinux_enabled_boot) 7358 return 0; 7359 7360 pr_debug("SELinux: Registering netfilter hooks\n"); 7361 7362 err = register_pernet_subsys(&selinux_net_ops); 7363 if (err) 7364 panic("SELinux: register_pernet_subsys: error %d\n", err); 7365 7366 return 0; 7367 } 7368 __initcall(selinux_nf_ip_init); 7369 7370 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7371 static void selinux_nf_ip_exit(void) 7372 { 7373 pr_debug("SELinux: Unregistering netfilter hooks\n"); 7374 7375 unregister_pernet_subsys(&selinux_net_ops); 7376 } 7377 #endif 7378 7379 #else /* CONFIG_NETFILTER */ 7380 7381 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7382 #define selinux_nf_ip_exit() 7383 #endif 7384 7385 #endif /* CONFIG_NETFILTER */ 7386 7387 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7388 int selinux_disable(struct selinux_state *state) 7389 { 7390 if (selinux_initialized(state)) { 7391 /* Not permitted after initial policy load. */ 7392 return -EINVAL; 7393 } 7394 7395 if (selinux_disabled(state)) { 7396 /* Only do this once. */ 7397 return -EINVAL; 7398 } 7399 7400 selinux_mark_disabled(state); 7401 7402 pr_info("SELinux: Disabled at runtime.\n"); 7403 7404 /* 7405 * Unregister netfilter hooks. 7406 * Must be done before security_delete_hooks() to avoid breaking 7407 * runtime disable. 7408 */ 7409 selinux_nf_ip_exit(); 7410 7411 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 7412 7413 /* Try to destroy the avc node cache */ 7414 avc_disable(); 7415 7416 /* Unregister selinuxfs. */ 7417 exit_sel_fs(); 7418 7419 return 0; 7420 } 7421 #endif 7422