1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Security-Enhanced Linux (SELinux) security module 4 * 5 * This file contains the SELinux hook function implementations. 6 * 7 * Authors: Stephen Smalley, <stephen.smalley.work@gmail.com> 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/errno.h> 29 #include <linux/sched/signal.h> 30 #include <linux/sched/task.h> 31 #include <linux/lsm_hooks.h> 32 #include <linux/xattr.h> 33 #include <linux/capability.h> 34 #include <linux/unistd.h> 35 #include <linux/mm.h> 36 #include <linux/mman.h> 37 #include <linux/slab.h> 38 #include <linux/pagemap.h> 39 #include <linux/proc_fs.h> 40 #include <linux/swap.h> 41 #include <linux/spinlock.h> 42 #include <linux/syscalls.h> 43 #include <linux/dcache.h> 44 #include <linux/file.h> 45 #include <linux/fdtable.h> 46 #include <linux/namei.h> 47 #include <linux/mount.h> 48 #include <linux/fs_context.h> 49 #include <linux/fs_parser.h> 50 #include <linux/netfilter_ipv4.h> 51 #include <linux/netfilter_ipv6.h> 52 #include <linux/tty.h> 53 #include <net/icmp.h> 54 #include <net/ip.h> /* for local_port_range[] */ 55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 56 #include <net/inet_connection_sock.h> 57 #include <net/net_namespace.h> 58 #include <net/netlabel.h> 59 #include <linux/uaccess.h> 60 #include <asm/ioctls.h> 61 #include <linux/atomic.h> 62 #include <linux/bitops.h> 63 #include <linux/interrupt.h> 64 #include <linux/netdevice.h> /* for network interface checks */ 65 #include <net/netlink.h> 66 #include <linux/tcp.h> 67 #include <linux/udp.h> 68 #include <linux/dccp.h> 69 #include <linux/sctp.h> 70 #include <net/sctp/structs.h> 71 #include <linux/quota.h> 72 #include <linux/un.h> /* for Unix socket types */ 73 #include <net/af_unix.h> /* for Unix socket types */ 74 #include <linux/parser.h> 75 #include <linux/nfs_mount.h> 76 #include <net/ipv6.h> 77 #include <linux/hugetlb.h> 78 #include <linux/personality.h> 79 #include <linux/audit.h> 80 #include <linux/string.h> 81 #include <linux/mutex.h> 82 #include <linux/posix-timers.h> 83 #include <linux/syslog.h> 84 #include <linux/user_namespace.h> 85 #include <linux/export.h> 86 #include <linux/msg.h> 87 #include <linux/shm.h> 88 #include <linux/bpf.h> 89 #include <linux/kernfs.h> 90 #include <linux/stringhash.h> /* for hashlen_string() */ 91 #include <uapi/linux/mount.h> 92 #include <linux/fsnotify.h> 93 #include <linux/fanotify.h> 94 #include <linux/io_uring.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 #define SELINUX_INODE_INIT_XATTRS 1 108 109 struct selinux_state selinux_state; 110 111 /* SECMARK reference count */ 112 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 113 114 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 115 static int selinux_enforcing_boot __initdata; 116 117 static int __init enforcing_setup(char *str) 118 { 119 unsigned long enforcing; 120 if (!kstrtoul(str, 0, &enforcing)) 121 selinux_enforcing_boot = enforcing ? 1 : 0; 122 return 1; 123 } 124 __setup("enforcing=", enforcing_setup); 125 #else 126 #define selinux_enforcing_boot 1 127 #endif 128 129 int selinux_enabled_boot __initdata = 1; 130 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 131 static int __init selinux_enabled_setup(char *str) 132 { 133 unsigned long enabled; 134 if (!kstrtoul(str, 0, &enabled)) 135 selinux_enabled_boot = enabled ? 1 : 0; 136 return 1; 137 } 138 __setup("selinux=", selinux_enabled_setup); 139 #endif 140 141 static int __init checkreqprot_setup(char *str) 142 { 143 unsigned long checkreqprot; 144 145 if (!kstrtoul(str, 0, &checkreqprot)) { 146 if (checkreqprot) 147 pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n"); 148 } 149 return 1; 150 } 151 __setup("checkreqprot=", checkreqprot_setup); 152 153 /** 154 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 155 * 156 * Description: 157 * This function checks the SECMARK reference counter to see if any SECMARK 158 * targets are currently configured, if the reference counter is greater than 159 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 160 * enabled, false (0) if SECMARK is disabled. If the always_check_network 161 * policy capability is enabled, SECMARK is always considered enabled. 162 * 163 */ 164 static int selinux_secmark_enabled(void) 165 { 166 return (selinux_policycap_alwaysnetwork() || 167 atomic_read(&selinux_secmark_refcount)); 168 } 169 170 /** 171 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 172 * 173 * Description: 174 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 175 * (1) if any are enabled or false (0) if neither are enabled. If the 176 * always_check_network policy capability is enabled, peer labeling 177 * is always considered enabled. 178 * 179 */ 180 static int selinux_peerlbl_enabled(void) 181 { 182 return (selinux_policycap_alwaysnetwork() || 183 netlbl_enabled() || selinux_xfrm_enabled()); 184 } 185 186 static int selinux_netcache_avc_callback(u32 event) 187 { 188 if (event == AVC_CALLBACK_RESET) { 189 sel_netif_flush(); 190 sel_netnode_flush(); 191 sel_netport_flush(); 192 synchronize_net(); 193 } 194 return 0; 195 } 196 197 static int selinux_lsm_notifier_avc_callback(u32 event) 198 { 199 if (event == AVC_CALLBACK_RESET) { 200 sel_ib_pkey_flush(); 201 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 202 } 203 204 return 0; 205 } 206 207 /* 208 * initialise the security for the init task 209 */ 210 static void cred_init_security(void) 211 { 212 struct task_security_struct *tsec; 213 214 tsec = selinux_cred(unrcu_pointer(current->real_cred)); 215 tsec->osid = tsec->sid = SECINITSID_KERNEL; 216 } 217 218 /* 219 * get the security ID of a set of credentials 220 */ 221 static inline u32 cred_sid(const struct cred *cred) 222 { 223 const struct task_security_struct *tsec; 224 225 tsec = selinux_cred(cred); 226 return tsec->sid; 227 } 228 229 static void __ad_net_init(struct common_audit_data *ad, 230 struct lsm_network_audit *net, 231 int ifindex, struct sock *sk, u16 family) 232 { 233 ad->type = LSM_AUDIT_DATA_NET; 234 ad->u.net = net; 235 net->netif = ifindex; 236 net->sk = sk; 237 net->family = family; 238 } 239 240 static void ad_net_init_from_sk(struct common_audit_data *ad, 241 struct lsm_network_audit *net, 242 struct sock *sk) 243 { 244 __ad_net_init(ad, net, 0, sk, 0); 245 } 246 247 static void ad_net_init_from_iif(struct common_audit_data *ad, 248 struct lsm_network_audit *net, 249 int ifindex, u16 family) 250 { 251 __ad_net_init(ad, net, ifindex, NULL, family); 252 } 253 254 /* 255 * get the objective security ID of a task 256 */ 257 static inline u32 task_sid_obj(const struct task_struct *task) 258 { 259 u32 sid; 260 261 rcu_read_lock(); 262 sid = cred_sid(__task_cred(task)); 263 rcu_read_unlock(); 264 return sid; 265 } 266 267 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 268 269 /* 270 * Try reloading inode security labels that have been marked as invalid. The 271 * @may_sleep parameter indicates when sleeping and thus reloading labels is 272 * allowed; when set to false, returns -ECHILD when the label is 273 * invalid. The @dentry parameter should be set to a dentry of the inode. 274 */ 275 static int __inode_security_revalidate(struct inode *inode, 276 struct dentry *dentry, 277 bool may_sleep) 278 { 279 struct inode_security_struct *isec = selinux_inode(inode); 280 281 might_sleep_if(may_sleep); 282 283 if (selinux_initialized() && 284 isec->initialized != LABEL_INITIALIZED) { 285 if (!may_sleep) 286 return -ECHILD; 287 288 /* 289 * Try reloading the inode security label. This will fail if 290 * @opt_dentry is NULL and no dentry for this inode can be 291 * found; in that case, continue using the old label. 292 */ 293 inode_doinit_with_dentry(inode, dentry); 294 } 295 return 0; 296 } 297 298 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 299 { 300 return selinux_inode(inode); 301 } 302 303 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 304 { 305 int error; 306 307 error = __inode_security_revalidate(inode, NULL, !rcu); 308 if (error) 309 return ERR_PTR(error); 310 return selinux_inode(inode); 311 } 312 313 /* 314 * Get the security label of an inode. 315 */ 316 static struct inode_security_struct *inode_security(struct inode *inode) 317 { 318 __inode_security_revalidate(inode, NULL, true); 319 return selinux_inode(inode); 320 } 321 322 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 323 { 324 struct inode *inode = d_backing_inode(dentry); 325 326 return selinux_inode(inode); 327 } 328 329 /* 330 * Get the security label of a dentry's backing inode. 331 */ 332 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 333 { 334 struct inode *inode = d_backing_inode(dentry); 335 336 __inode_security_revalidate(inode, dentry, true); 337 return selinux_inode(inode); 338 } 339 340 static void inode_free_security(struct inode *inode) 341 { 342 struct inode_security_struct *isec = selinux_inode(inode); 343 struct superblock_security_struct *sbsec; 344 345 if (!isec) 346 return; 347 sbsec = selinux_superblock(inode->i_sb); 348 /* 349 * As not all inode security structures are in a list, we check for 350 * empty list outside of the lock to make sure that we won't waste 351 * time taking a lock doing nothing. 352 * 353 * The list_del_init() function can be safely called more than once. 354 * It should not be possible for this function to be called with 355 * concurrent list_add(), but for better safety against future changes 356 * in the code, we use list_empty_careful() here. 357 */ 358 if (!list_empty_careful(&isec->list)) { 359 spin_lock(&sbsec->isec_lock); 360 list_del_init(&isec->list); 361 spin_unlock(&sbsec->isec_lock); 362 } 363 } 364 365 struct selinux_mnt_opts { 366 u32 fscontext_sid; 367 u32 context_sid; 368 u32 rootcontext_sid; 369 u32 defcontext_sid; 370 }; 371 372 static void selinux_free_mnt_opts(void *mnt_opts) 373 { 374 kfree(mnt_opts); 375 } 376 377 enum { 378 Opt_error = -1, 379 Opt_context = 0, 380 Opt_defcontext = 1, 381 Opt_fscontext = 2, 382 Opt_rootcontext = 3, 383 Opt_seclabel = 4, 384 }; 385 386 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 387 static const struct { 388 const char *name; 389 int len; 390 int opt; 391 bool has_arg; 392 } tokens[] = { 393 A(context, true), 394 A(fscontext, true), 395 A(defcontext, true), 396 A(rootcontext, true), 397 A(seclabel, false), 398 }; 399 #undef A 400 401 static int match_opt_prefix(char *s, int l, char **arg) 402 { 403 int i; 404 405 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 406 size_t len = tokens[i].len; 407 if (len > l || memcmp(s, tokens[i].name, len)) 408 continue; 409 if (tokens[i].has_arg) { 410 if (len == l || s[len] != '=') 411 continue; 412 *arg = s + len + 1; 413 } else if (len != l) 414 continue; 415 return tokens[i].opt; 416 } 417 return Opt_error; 418 } 419 420 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 421 422 static int may_context_mount_sb_relabel(u32 sid, 423 struct superblock_security_struct *sbsec, 424 const struct cred *cred) 425 { 426 const struct task_security_struct *tsec = selinux_cred(cred); 427 int rc; 428 429 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 430 FILESYSTEM__RELABELFROM, NULL); 431 if (rc) 432 return rc; 433 434 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 435 FILESYSTEM__RELABELTO, NULL); 436 return rc; 437 } 438 439 static int may_context_mount_inode_relabel(u32 sid, 440 struct superblock_security_struct *sbsec, 441 const struct cred *cred) 442 { 443 const struct task_security_struct *tsec = selinux_cred(cred); 444 int rc; 445 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 446 FILESYSTEM__RELABELFROM, NULL); 447 if (rc) 448 return rc; 449 450 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 451 FILESYSTEM__ASSOCIATE, NULL); 452 return rc; 453 } 454 455 static int selinux_is_genfs_special_handling(struct super_block *sb) 456 { 457 /* Special handling. Genfs but also in-core setxattr handler */ 458 return !strcmp(sb->s_type->name, "sysfs") || 459 !strcmp(sb->s_type->name, "pstore") || 460 !strcmp(sb->s_type->name, "debugfs") || 461 !strcmp(sb->s_type->name, "tracefs") || 462 !strcmp(sb->s_type->name, "rootfs") || 463 (selinux_policycap_cgroupseclabel() && 464 (!strcmp(sb->s_type->name, "cgroup") || 465 !strcmp(sb->s_type->name, "cgroup2"))); 466 } 467 468 static int selinux_is_sblabel_mnt(struct super_block *sb) 469 { 470 struct superblock_security_struct *sbsec = selinux_superblock(sb); 471 472 /* 473 * IMPORTANT: Double-check logic in this function when adding a new 474 * SECURITY_FS_USE_* definition! 475 */ 476 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 477 478 switch (sbsec->behavior) { 479 case SECURITY_FS_USE_XATTR: 480 case SECURITY_FS_USE_TRANS: 481 case SECURITY_FS_USE_TASK: 482 case SECURITY_FS_USE_NATIVE: 483 return 1; 484 485 case SECURITY_FS_USE_GENFS: 486 return selinux_is_genfs_special_handling(sb); 487 488 /* Never allow relabeling on context mounts */ 489 case SECURITY_FS_USE_MNTPOINT: 490 case SECURITY_FS_USE_NONE: 491 default: 492 return 0; 493 } 494 } 495 496 static int sb_check_xattr_support(struct super_block *sb) 497 { 498 struct superblock_security_struct *sbsec = selinux_superblock(sb); 499 struct dentry *root = sb->s_root; 500 struct inode *root_inode = d_backing_inode(root); 501 u32 sid; 502 int rc; 503 504 /* 505 * Make sure that the xattr handler exists and that no 506 * error other than -ENODATA is returned by getxattr on 507 * the root directory. -ENODATA is ok, as this may be 508 * the first boot of the SELinux kernel before we have 509 * assigned xattr values to the filesystem. 510 */ 511 if (!(root_inode->i_opflags & IOP_XATTR)) { 512 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", 513 sb->s_id, sb->s_type->name); 514 goto fallback; 515 } 516 517 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 518 if (rc < 0 && rc != -ENODATA) { 519 if (rc == -EOPNOTSUPP) { 520 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", 521 sb->s_id, sb->s_type->name); 522 goto fallback; 523 } else { 524 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", 525 sb->s_id, sb->s_type->name, -rc); 526 return rc; 527 } 528 } 529 return 0; 530 531 fallback: 532 /* No xattr support - try to fallback to genfs if possible. */ 533 rc = security_genfs_sid(sb->s_type->name, "/", 534 SECCLASS_DIR, &sid); 535 if (rc) 536 return -EOPNOTSUPP; 537 538 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", 539 sb->s_id, sb->s_type->name); 540 sbsec->behavior = SECURITY_FS_USE_GENFS; 541 sbsec->sid = sid; 542 return 0; 543 } 544 545 static int sb_finish_set_opts(struct super_block *sb) 546 { 547 struct superblock_security_struct *sbsec = selinux_superblock(sb); 548 struct dentry *root = sb->s_root; 549 struct inode *root_inode = d_backing_inode(root); 550 int rc = 0; 551 552 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 553 rc = sb_check_xattr_support(sb); 554 if (rc) 555 return rc; 556 } 557 558 sbsec->flags |= SE_SBINITIALIZED; 559 560 /* 561 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 562 * leave the flag untouched because sb_clone_mnt_opts might be handing 563 * us a superblock that needs the flag to be cleared. 564 */ 565 if (selinux_is_sblabel_mnt(sb)) 566 sbsec->flags |= SBLABEL_MNT; 567 else 568 sbsec->flags &= ~SBLABEL_MNT; 569 570 /* Initialize the root inode. */ 571 rc = inode_doinit_with_dentry(root_inode, root); 572 573 /* Initialize any other inodes associated with the superblock, e.g. 574 inodes created prior to initial policy load or inodes created 575 during get_sb by a pseudo filesystem that directly 576 populates itself. */ 577 spin_lock(&sbsec->isec_lock); 578 while (!list_empty(&sbsec->isec_head)) { 579 struct inode_security_struct *isec = 580 list_first_entry(&sbsec->isec_head, 581 struct inode_security_struct, list); 582 struct inode *inode = isec->inode; 583 list_del_init(&isec->list); 584 spin_unlock(&sbsec->isec_lock); 585 inode = igrab(inode); 586 if (inode) { 587 if (!IS_PRIVATE(inode)) 588 inode_doinit_with_dentry(inode, NULL); 589 iput(inode); 590 } 591 spin_lock(&sbsec->isec_lock); 592 } 593 spin_unlock(&sbsec->isec_lock); 594 return rc; 595 } 596 597 static int bad_option(struct superblock_security_struct *sbsec, char flag, 598 u32 old_sid, u32 new_sid) 599 { 600 char mnt_flags = sbsec->flags & SE_MNTMASK; 601 602 /* check if the old mount command had the same options */ 603 if (sbsec->flags & SE_SBINITIALIZED) 604 if (!(sbsec->flags & flag) || 605 (old_sid != new_sid)) 606 return 1; 607 608 /* check if we were passed the same options twice, 609 * aka someone passed context=a,context=b 610 */ 611 if (!(sbsec->flags & SE_SBINITIALIZED)) 612 if (mnt_flags & flag) 613 return 1; 614 return 0; 615 } 616 617 /* 618 * Allow filesystems with binary mount data to explicitly set mount point 619 * labeling information. 620 */ 621 static int selinux_set_mnt_opts(struct super_block *sb, 622 void *mnt_opts, 623 unsigned long kern_flags, 624 unsigned long *set_kern_flags) 625 { 626 const struct cred *cred = current_cred(); 627 struct superblock_security_struct *sbsec = selinux_superblock(sb); 628 struct dentry *root = sb->s_root; 629 struct selinux_mnt_opts *opts = mnt_opts; 630 struct inode_security_struct *root_isec; 631 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 632 u32 defcontext_sid = 0; 633 int rc = 0; 634 635 /* 636 * Specifying internal flags without providing a place to 637 * place the results is not allowed 638 */ 639 if (kern_flags && !set_kern_flags) 640 return -EINVAL; 641 642 mutex_lock(&sbsec->lock); 643 644 if (!selinux_initialized()) { 645 if (!opts) { 646 /* Defer initialization until selinux_complete_init, 647 after the initial policy is loaded and the security 648 server is ready to handle calls. */ 649 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 650 sbsec->flags |= SE_SBNATIVE; 651 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 652 } 653 goto out; 654 } 655 rc = -EINVAL; 656 pr_warn("SELinux: Unable to set superblock options " 657 "before the security server is initialized\n"); 658 goto out; 659 } 660 661 /* 662 * Binary mount data FS will come through this function twice. Once 663 * from an explicit call and once from the generic calls from the vfs. 664 * Since the generic VFS calls will not contain any security mount data 665 * we need to skip the double mount verification. 666 * 667 * This does open a hole in which we will not notice if the first 668 * mount using this sb set explicit options and a second mount using 669 * this sb does not set any security options. (The first options 670 * will be used for both mounts) 671 */ 672 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 673 && !opts) 674 goto out; 675 676 root_isec = backing_inode_security_novalidate(root); 677 678 /* 679 * parse the mount options, check if they are valid sids. 680 * also check if someone is trying to mount the same sb more 681 * than once with different security options. 682 */ 683 if (opts) { 684 if (opts->fscontext_sid) { 685 fscontext_sid = opts->fscontext_sid; 686 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 687 fscontext_sid)) 688 goto out_double_mount; 689 sbsec->flags |= FSCONTEXT_MNT; 690 } 691 if (opts->context_sid) { 692 context_sid = opts->context_sid; 693 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 694 context_sid)) 695 goto out_double_mount; 696 sbsec->flags |= CONTEXT_MNT; 697 } 698 if (opts->rootcontext_sid) { 699 rootcontext_sid = opts->rootcontext_sid; 700 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 701 rootcontext_sid)) 702 goto out_double_mount; 703 sbsec->flags |= ROOTCONTEXT_MNT; 704 } 705 if (opts->defcontext_sid) { 706 defcontext_sid = opts->defcontext_sid; 707 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 708 defcontext_sid)) 709 goto out_double_mount; 710 sbsec->flags |= DEFCONTEXT_MNT; 711 } 712 } 713 714 if (sbsec->flags & SE_SBINITIALIZED) { 715 /* previously mounted with options, but not on this attempt? */ 716 if ((sbsec->flags & SE_MNTMASK) && !opts) 717 goto out_double_mount; 718 rc = 0; 719 goto out; 720 } 721 722 if (strcmp(sb->s_type->name, "proc") == 0) 723 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 724 725 if (!strcmp(sb->s_type->name, "debugfs") || 726 !strcmp(sb->s_type->name, "tracefs") || 727 !strcmp(sb->s_type->name, "binder") || 728 !strcmp(sb->s_type->name, "bpf") || 729 !strcmp(sb->s_type->name, "pstore") || 730 !strcmp(sb->s_type->name, "securityfs")) 731 sbsec->flags |= SE_SBGENFS; 732 733 if (!strcmp(sb->s_type->name, "sysfs") || 734 !strcmp(sb->s_type->name, "cgroup") || 735 !strcmp(sb->s_type->name, "cgroup2")) 736 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 737 738 if (!sbsec->behavior) { 739 /* 740 * Determine the labeling behavior to use for this 741 * filesystem type. 742 */ 743 rc = security_fs_use(sb); 744 if (rc) { 745 pr_warn("%s: security_fs_use(%s) returned %d\n", 746 __func__, sb->s_type->name, rc); 747 goto out; 748 } 749 } 750 751 /* 752 * If this is a user namespace mount and the filesystem type is not 753 * explicitly whitelisted, then no contexts are allowed on the command 754 * line and security labels must be ignored. 755 */ 756 if (sb->s_user_ns != &init_user_ns && 757 strcmp(sb->s_type->name, "tmpfs") && 758 strcmp(sb->s_type->name, "ramfs") && 759 strcmp(sb->s_type->name, "devpts") && 760 strcmp(sb->s_type->name, "overlay")) { 761 if (context_sid || fscontext_sid || rootcontext_sid || 762 defcontext_sid) { 763 rc = -EACCES; 764 goto out; 765 } 766 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 767 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 768 rc = security_transition_sid(current_sid(), 769 current_sid(), 770 SECCLASS_FILE, NULL, 771 &sbsec->mntpoint_sid); 772 if (rc) 773 goto out; 774 } 775 goto out_set_opts; 776 } 777 778 /* sets the context of the superblock for the fs being mounted. */ 779 if (fscontext_sid) { 780 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 781 if (rc) 782 goto out; 783 784 sbsec->sid = fscontext_sid; 785 } 786 787 /* 788 * Switch to using mount point labeling behavior. 789 * sets the label used on all file below the mountpoint, and will set 790 * the superblock context if not already set. 791 */ 792 if (sbsec->flags & SE_SBNATIVE) { 793 /* 794 * This means we are initializing a superblock that has been 795 * mounted before the SELinux was initialized and the 796 * filesystem requested native labeling. We had already 797 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags 798 * in the original mount attempt, so now we just need to set 799 * the SECURITY_FS_USE_NATIVE behavior. 800 */ 801 sbsec->behavior = SECURITY_FS_USE_NATIVE; 802 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 803 sbsec->behavior = SECURITY_FS_USE_NATIVE; 804 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 805 } 806 807 if (context_sid) { 808 if (!fscontext_sid) { 809 rc = may_context_mount_sb_relabel(context_sid, sbsec, 810 cred); 811 if (rc) 812 goto out; 813 sbsec->sid = context_sid; 814 } else { 815 rc = may_context_mount_inode_relabel(context_sid, sbsec, 816 cred); 817 if (rc) 818 goto out; 819 } 820 if (!rootcontext_sid) 821 rootcontext_sid = context_sid; 822 823 sbsec->mntpoint_sid = context_sid; 824 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 825 } 826 827 if (rootcontext_sid) { 828 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 829 cred); 830 if (rc) 831 goto out; 832 833 root_isec->sid = rootcontext_sid; 834 root_isec->initialized = LABEL_INITIALIZED; 835 } 836 837 if (defcontext_sid) { 838 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 839 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 840 rc = -EINVAL; 841 pr_warn("SELinux: defcontext option is " 842 "invalid for this filesystem type\n"); 843 goto out; 844 } 845 846 if (defcontext_sid != sbsec->def_sid) { 847 rc = may_context_mount_inode_relabel(defcontext_sid, 848 sbsec, cred); 849 if (rc) 850 goto out; 851 } 852 853 sbsec->def_sid = defcontext_sid; 854 } 855 856 out_set_opts: 857 rc = sb_finish_set_opts(sb); 858 out: 859 mutex_unlock(&sbsec->lock); 860 return rc; 861 out_double_mount: 862 rc = -EINVAL; 863 pr_warn("SELinux: mount invalid. Same superblock, different " 864 "security settings for (dev %s, type %s)\n", sb->s_id, 865 sb->s_type->name); 866 goto out; 867 } 868 869 static int selinux_cmp_sb_context(const struct super_block *oldsb, 870 const struct super_block *newsb) 871 { 872 struct superblock_security_struct *old = selinux_superblock(oldsb); 873 struct superblock_security_struct *new = selinux_superblock(newsb); 874 char oldflags = old->flags & SE_MNTMASK; 875 char newflags = new->flags & SE_MNTMASK; 876 877 if (oldflags != newflags) 878 goto mismatch; 879 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 880 goto mismatch; 881 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 882 goto mismatch; 883 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 884 goto mismatch; 885 if (oldflags & ROOTCONTEXT_MNT) { 886 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 887 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 888 if (oldroot->sid != newroot->sid) 889 goto mismatch; 890 } 891 return 0; 892 mismatch: 893 pr_warn("SELinux: mount invalid. Same superblock, " 894 "different security settings for (dev %s, " 895 "type %s)\n", newsb->s_id, newsb->s_type->name); 896 return -EBUSY; 897 } 898 899 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 900 struct super_block *newsb, 901 unsigned long kern_flags, 902 unsigned long *set_kern_flags) 903 { 904 int rc = 0; 905 const struct superblock_security_struct *oldsbsec = 906 selinux_superblock(oldsb); 907 struct superblock_security_struct *newsbsec = selinux_superblock(newsb); 908 909 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 910 int set_context = (oldsbsec->flags & CONTEXT_MNT); 911 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 912 913 /* 914 * Specifying internal flags without providing a place to 915 * place the results is not allowed. 916 */ 917 if (kern_flags && !set_kern_flags) 918 return -EINVAL; 919 920 mutex_lock(&newsbsec->lock); 921 922 /* 923 * if the parent was able to be mounted it clearly had no special lsm 924 * mount options. thus we can safely deal with this superblock later 925 */ 926 if (!selinux_initialized()) { 927 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 928 newsbsec->flags |= SE_SBNATIVE; 929 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 930 } 931 goto out; 932 } 933 934 /* how can we clone if the old one wasn't set up?? */ 935 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 936 937 /* if fs is reusing a sb, make sure that the contexts match */ 938 if (newsbsec->flags & SE_SBINITIALIZED) { 939 mutex_unlock(&newsbsec->lock); 940 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 941 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 942 return selinux_cmp_sb_context(oldsb, newsb); 943 } 944 945 newsbsec->flags = oldsbsec->flags; 946 947 newsbsec->sid = oldsbsec->sid; 948 newsbsec->def_sid = oldsbsec->def_sid; 949 newsbsec->behavior = oldsbsec->behavior; 950 951 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 952 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 953 rc = security_fs_use(newsb); 954 if (rc) 955 goto out; 956 } 957 958 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 959 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 960 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 961 } 962 963 if (set_context) { 964 u32 sid = oldsbsec->mntpoint_sid; 965 966 if (!set_fscontext) 967 newsbsec->sid = sid; 968 if (!set_rootcontext) { 969 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 970 newisec->sid = sid; 971 } 972 newsbsec->mntpoint_sid = sid; 973 } 974 if (set_rootcontext) { 975 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 976 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 977 978 newisec->sid = oldisec->sid; 979 } 980 981 sb_finish_set_opts(newsb); 982 out: 983 mutex_unlock(&newsbsec->lock); 984 return rc; 985 } 986 987 /* 988 * NOTE: the caller is responsible for freeing the memory even if on error. 989 */ 990 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 991 { 992 struct selinux_mnt_opts *opts = *mnt_opts; 993 u32 *dst_sid; 994 int rc; 995 996 if (token == Opt_seclabel) 997 /* eaten and completely ignored */ 998 return 0; 999 if (!s) 1000 return -EINVAL; 1001 1002 if (!selinux_initialized()) { 1003 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); 1004 return -EINVAL; 1005 } 1006 1007 if (!opts) { 1008 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 1009 if (!opts) 1010 return -ENOMEM; 1011 *mnt_opts = opts; 1012 } 1013 1014 switch (token) { 1015 case Opt_context: 1016 if (opts->context_sid || opts->defcontext_sid) 1017 goto err; 1018 dst_sid = &opts->context_sid; 1019 break; 1020 case Opt_fscontext: 1021 if (opts->fscontext_sid) 1022 goto err; 1023 dst_sid = &opts->fscontext_sid; 1024 break; 1025 case Opt_rootcontext: 1026 if (opts->rootcontext_sid) 1027 goto err; 1028 dst_sid = &opts->rootcontext_sid; 1029 break; 1030 case Opt_defcontext: 1031 if (opts->context_sid || opts->defcontext_sid) 1032 goto err; 1033 dst_sid = &opts->defcontext_sid; 1034 break; 1035 default: 1036 WARN_ON(1); 1037 return -EINVAL; 1038 } 1039 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); 1040 if (rc) 1041 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", 1042 s, rc); 1043 return rc; 1044 1045 err: 1046 pr_warn(SEL_MOUNT_FAIL_MSG); 1047 return -EINVAL; 1048 } 1049 1050 static int show_sid(struct seq_file *m, u32 sid) 1051 { 1052 char *context = NULL; 1053 u32 len; 1054 int rc; 1055 1056 rc = security_sid_to_context(sid, &context, &len); 1057 if (!rc) { 1058 bool has_comma = strchr(context, ','); 1059 1060 seq_putc(m, '='); 1061 if (has_comma) 1062 seq_putc(m, '\"'); 1063 seq_escape(m, context, "\"\n\\"); 1064 if (has_comma) 1065 seq_putc(m, '\"'); 1066 } 1067 kfree(context); 1068 return rc; 1069 } 1070 1071 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1072 { 1073 struct superblock_security_struct *sbsec = selinux_superblock(sb); 1074 int rc; 1075 1076 if (!(sbsec->flags & SE_SBINITIALIZED)) 1077 return 0; 1078 1079 if (!selinux_initialized()) 1080 return 0; 1081 1082 if (sbsec->flags & FSCONTEXT_MNT) { 1083 seq_putc(m, ','); 1084 seq_puts(m, FSCONTEXT_STR); 1085 rc = show_sid(m, sbsec->sid); 1086 if (rc) 1087 return rc; 1088 } 1089 if (sbsec->flags & CONTEXT_MNT) { 1090 seq_putc(m, ','); 1091 seq_puts(m, CONTEXT_STR); 1092 rc = show_sid(m, sbsec->mntpoint_sid); 1093 if (rc) 1094 return rc; 1095 } 1096 if (sbsec->flags & DEFCONTEXT_MNT) { 1097 seq_putc(m, ','); 1098 seq_puts(m, DEFCONTEXT_STR); 1099 rc = show_sid(m, sbsec->def_sid); 1100 if (rc) 1101 return rc; 1102 } 1103 if (sbsec->flags & ROOTCONTEXT_MNT) { 1104 struct dentry *root = sb->s_root; 1105 struct inode_security_struct *isec = backing_inode_security(root); 1106 seq_putc(m, ','); 1107 seq_puts(m, ROOTCONTEXT_STR); 1108 rc = show_sid(m, isec->sid); 1109 if (rc) 1110 return rc; 1111 } 1112 if (sbsec->flags & SBLABEL_MNT) { 1113 seq_putc(m, ','); 1114 seq_puts(m, SECLABEL_STR); 1115 } 1116 return 0; 1117 } 1118 1119 static inline u16 inode_mode_to_security_class(umode_t mode) 1120 { 1121 switch (mode & S_IFMT) { 1122 case S_IFSOCK: 1123 return SECCLASS_SOCK_FILE; 1124 case S_IFLNK: 1125 return SECCLASS_LNK_FILE; 1126 case S_IFREG: 1127 return SECCLASS_FILE; 1128 case S_IFBLK: 1129 return SECCLASS_BLK_FILE; 1130 case S_IFDIR: 1131 return SECCLASS_DIR; 1132 case S_IFCHR: 1133 return SECCLASS_CHR_FILE; 1134 case S_IFIFO: 1135 return SECCLASS_FIFO_FILE; 1136 1137 } 1138 1139 return SECCLASS_FILE; 1140 } 1141 1142 static inline int default_protocol_stream(int protocol) 1143 { 1144 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || 1145 protocol == IPPROTO_MPTCP); 1146 } 1147 1148 static inline int default_protocol_dgram(int protocol) 1149 { 1150 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1151 } 1152 1153 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1154 { 1155 bool extsockclass = selinux_policycap_extsockclass(); 1156 1157 switch (family) { 1158 case PF_UNIX: 1159 switch (type) { 1160 case SOCK_STREAM: 1161 case SOCK_SEQPACKET: 1162 return SECCLASS_UNIX_STREAM_SOCKET; 1163 case SOCK_DGRAM: 1164 case SOCK_RAW: 1165 return SECCLASS_UNIX_DGRAM_SOCKET; 1166 } 1167 break; 1168 case PF_INET: 1169 case PF_INET6: 1170 switch (type) { 1171 case SOCK_STREAM: 1172 case SOCK_SEQPACKET: 1173 if (default_protocol_stream(protocol)) 1174 return SECCLASS_TCP_SOCKET; 1175 else if (extsockclass && protocol == IPPROTO_SCTP) 1176 return SECCLASS_SCTP_SOCKET; 1177 else 1178 return SECCLASS_RAWIP_SOCKET; 1179 case SOCK_DGRAM: 1180 if (default_protocol_dgram(protocol)) 1181 return SECCLASS_UDP_SOCKET; 1182 else if (extsockclass && (protocol == IPPROTO_ICMP || 1183 protocol == IPPROTO_ICMPV6)) 1184 return SECCLASS_ICMP_SOCKET; 1185 else 1186 return SECCLASS_RAWIP_SOCKET; 1187 case SOCK_DCCP: 1188 return SECCLASS_DCCP_SOCKET; 1189 default: 1190 return SECCLASS_RAWIP_SOCKET; 1191 } 1192 break; 1193 case PF_NETLINK: 1194 switch (protocol) { 1195 case NETLINK_ROUTE: 1196 return SECCLASS_NETLINK_ROUTE_SOCKET; 1197 case NETLINK_SOCK_DIAG: 1198 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1199 case NETLINK_NFLOG: 1200 return SECCLASS_NETLINK_NFLOG_SOCKET; 1201 case NETLINK_XFRM: 1202 return SECCLASS_NETLINK_XFRM_SOCKET; 1203 case NETLINK_SELINUX: 1204 return SECCLASS_NETLINK_SELINUX_SOCKET; 1205 case NETLINK_ISCSI: 1206 return SECCLASS_NETLINK_ISCSI_SOCKET; 1207 case NETLINK_AUDIT: 1208 return SECCLASS_NETLINK_AUDIT_SOCKET; 1209 case NETLINK_FIB_LOOKUP: 1210 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1211 case NETLINK_CONNECTOR: 1212 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1213 case NETLINK_NETFILTER: 1214 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1215 case NETLINK_DNRTMSG: 1216 return SECCLASS_NETLINK_DNRT_SOCKET; 1217 case NETLINK_KOBJECT_UEVENT: 1218 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1219 case NETLINK_GENERIC: 1220 return SECCLASS_NETLINK_GENERIC_SOCKET; 1221 case NETLINK_SCSITRANSPORT: 1222 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1223 case NETLINK_RDMA: 1224 return SECCLASS_NETLINK_RDMA_SOCKET; 1225 case NETLINK_CRYPTO: 1226 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1227 default: 1228 return SECCLASS_NETLINK_SOCKET; 1229 } 1230 case PF_PACKET: 1231 return SECCLASS_PACKET_SOCKET; 1232 case PF_KEY: 1233 return SECCLASS_KEY_SOCKET; 1234 case PF_APPLETALK: 1235 return SECCLASS_APPLETALK_SOCKET; 1236 } 1237 1238 if (extsockclass) { 1239 switch (family) { 1240 case PF_AX25: 1241 return SECCLASS_AX25_SOCKET; 1242 case PF_IPX: 1243 return SECCLASS_IPX_SOCKET; 1244 case PF_NETROM: 1245 return SECCLASS_NETROM_SOCKET; 1246 case PF_ATMPVC: 1247 return SECCLASS_ATMPVC_SOCKET; 1248 case PF_X25: 1249 return SECCLASS_X25_SOCKET; 1250 case PF_ROSE: 1251 return SECCLASS_ROSE_SOCKET; 1252 case PF_DECnet: 1253 return SECCLASS_DECNET_SOCKET; 1254 case PF_ATMSVC: 1255 return SECCLASS_ATMSVC_SOCKET; 1256 case PF_RDS: 1257 return SECCLASS_RDS_SOCKET; 1258 case PF_IRDA: 1259 return SECCLASS_IRDA_SOCKET; 1260 case PF_PPPOX: 1261 return SECCLASS_PPPOX_SOCKET; 1262 case PF_LLC: 1263 return SECCLASS_LLC_SOCKET; 1264 case PF_CAN: 1265 return SECCLASS_CAN_SOCKET; 1266 case PF_TIPC: 1267 return SECCLASS_TIPC_SOCKET; 1268 case PF_BLUETOOTH: 1269 return SECCLASS_BLUETOOTH_SOCKET; 1270 case PF_IUCV: 1271 return SECCLASS_IUCV_SOCKET; 1272 case PF_RXRPC: 1273 return SECCLASS_RXRPC_SOCKET; 1274 case PF_ISDN: 1275 return SECCLASS_ISDN_SOCKET; 1276 case PF_PHONET: 1277 return SECCLASS_PHONET_SOCKET; 1278 case PF_IEEE802154: 1279 return SECCLASS_IEEE802154_SOCKET; 1280 case PF_CAIF: 1281 return SECCLASS_CAIF_SOCKET; 1282 case PF_ALG: 1283 return SECCLASS_ALG_SOCKET; 1284 case PF_NFC: 1285 return SECCLASS_NFC_SOCKET; 1286 case PF_VSOCK: 1287 return SECCLASS_VSOCK_SOCKET; 1288 case PF_KCM: 1289 return SECCLASS_KCM_SOCKET; 1290 case PF_QIPCRTR: 1291 return SECCLASS_QIPCRTR_SOCKET; 1292 case PF_SMC: 1293 return SECCLASS_SMC_SOCKET; 1294 case PF_XDP: 1295 return SECCLASS_XDP_SOCKET; 1296 case PF_MCTP: 1297 return SECCLASS_MCTP_SOCKET; 1298 #if PF_MAX > 46 1299 #error New address family defined, please update this function. 1300 #endif 1301 } 1302 } 1303 1304 return SECCLASS_SOCKET; 1305 } 1306 1307 static int selinux_genfs_get_sid(struct dentry *dentry, 1308 u16 tclass, 1309 u16 flags, 1310 u32 *sid) 1311 { 1312 int rc; 1313 struct super_block *sb = dentry->d_sb; 1314 char *buffer, *path; 1315 1316 buffer = (char *)__get_free_page(GFP_KERNEL); 1317 if (!buffer) 1318 return -ENOMEM; 1319 1320 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1321 if (IS_ERR(path)) 1322 rc = PTR_ERR(path); 1323 else { 1324 if (flags & SE_SBPROC) { 1325 /* each process gets a /proc/PID/ entry. Strip off the 1326 * PID part to get a valid selinux labeling. 1327 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1328 while (path[1] >= '0' && path[1] <= '9') { 1329 path[1] = '/'; 1330 path++; 1331 } 1332 } 1333 rc = security_genfs_sid(sb->s_type->name, 1334 path, tclass, sid); 1335 if (rc == -ENOENT) { 1336 /* No match in policy, mark as unlabeled. */ 1337 *sid = SECINITSID_UNLABELED; 1338 rc = 0; 1339 } 1340 } 1341 free_page((unsigned long)buffer); 1342 return rc; 1343 } 1344 1345 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1346 u32 def_sid, u32 *sid) 1347 { 1348 #define INITCONTEXTLEN 255 1349 char *context; 1350 unsigned int len; 1351 int rc; 1352 1353 len = INITCONTEXTLEN; 1354 context = kmalloc(len + 1, GFP_NOFS); 1355 if (!context) 1356 return -ENOMEM; 1357 1358 context[len] = '\0'; 1359 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1360 if (rc == -ERANGE) { 1361 kfree(context); 1362 1363 /* Need a larger buffer. Query for the right size. */ 1364 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1365 if (rc < 0) 1366 return rc; 1367 1368 len = rc; 1369 context = kmalloc(len + 1, GFP_NOFS); 1370 if (!context) 1371 return -ENOMEM; 1372 1373 context[len] = '\0'; 1374 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1375 context, len); 1376 } 1377 if (rc < 0) { 1378 kfree(context); 1379 if (rc != -ENODATA) { 1380 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1381 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1382 return rc; 1383 } 1384 *sid = def_sid; 1385 return 0; 1386 } 1387 1388 rc = security_context_to_sid_default(context, rc, sid, 1389 def_sid, GFP_NOFS); 1390 if (rc) { 1391 char *dev = inode->i_sb->s_id; 1392 unsigned long ino = inode->i_ino; 1393 1394 if (rc == -EINVAL) { 1395 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", 1396 ino, dev, context); 1397 } else { 1398 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1399 __func__, context, -rc, dev, ino); 1400 } 1401 } 1402 kfree(context); 1403 return 0; 1404 } 1405 1406 /* The inode's security attributes must be initialized before first use. */ 1407 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1408 { 1409 struct superblock_security_struct *sbsec = NULL; 1410 struct inode_security_struct *isec = selinux_inode(inode); 1411 u32 task_sid, sid = 0; 1412 u16 sclass; 1413 struct dentry *dentry; 1414 int rc = 0; 1415 1416 if (isec->initialized == LABEL_INITIALIZED) 1417 return 0; 1418 1419 spin_lock(&isec->lock); 1420 if (isec->initialized == LABEL_INITIALIZED) 1421 goto out_unlock; 1422 1423 if (isec->sclass == SECCLASS_FILE) 1424 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1425 1426 sbsec = selinux_superblock(inode->i_sb); 1427 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1428 /* Defer initialization until selinux_complete_init, 1429 after the initial policy is loaded and the security 1430 server is ready to handle calls. */ 1431 spin_lock(&sbsec->isec_lock); 1432 if (list_empty(&isec->list)) 1433 list_add(&isec->list, &sbsec->isec_head); 1434 spin_unlock(&sbsec->isec_lock); 1435 goto out_unlock; 1436 } 1437 1438 sclass = isec->sclass; 1439 task_sid = isec->task_sid; 1440 sid = isec->sid; 1441 isec->initialized = LABEL_PENDING; 1442 spin_unlock(&isec->lock); 1443 1444 switch (sbsec->behavior) { 1445 /* 1446 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels 1447 * via xattr when called from delayed_superblock_init(). 1448 */ 1449 case SECURITY_FS_USE_NATIVE: 1450 case SECURITY_FS_USE_XATTR: 1451 if (!(inode->i_opflags & IOP_XATTR)) { 1452 sid = sbsec->def_sid; 1453 break; 1454 } 1455 /* Need a dentry, since the xattr API requires one. 1456 Life would be simpler if we could just pass the inode. */ 1457 if (opt_dentry) { 1458 /* Called from d_instantiate or d_splice_alias. */ 1459 dentry = dget(opt_dentry); 1460 } else { 1461 /* 1462 * Called from selinux_complete_init, try to find a dentry. 1463 * Some filesystems really want a connected one, so try 1464 * that first. We could split SECURITY_FS_USE_XATTR in 1465 * two, depending upon that... 1466 */ 1467 dentry = d_find_alias(inode); 1468 if (!dentry) 1469 dentry = d_find_any_alias(inode); 1470 } 1471 if (!dentry) { 1472 /* 1473 * this is can be hit on boot when a file is accessed 1474 * before the policy is loaded. When we load policy we 1475 * may find inodes that have no dentry on the 1476 * sbsec->isec_head list. No reason to complain as these 1477 * will get fixed up the next time we go through 1478 * inode_doinit with a dentry, before these inodes could 1479 * be used again by userspace. 1480 */ 1481 goto out_invalid; 1482 } 1483 1484 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1485 &sid); 1486 dput(dentry); 1487 if (rc) 1488 goto out; 1489 break; 1490 case SECURITY_FS_USE_TASK: 1491 sid = task_sid; 1492 break; 1493 case SECURITY_FS_USE_TRANS: 1494 /* Default to the fs SID. */ 1495 sid = sbsec->sid; 1496 1497 /* Try to obtain a transition SID. */ 1498 rc = security_transition_sid(task_sid, sid, 1499 sclass, NULL, &sid); 1500 if (rc) 1501 goto out; 1502 break; 1503 case SECURITY_FS_USE_MNTPOINT: 1504 sid = sbsec->mntpoint_sid; 1505 break; 1506 default: 1507 /* Default to the fs superblock SID. */ 1508 sid = sbsec->sid; 1509 1510 if ((sbsec->flags & SE_SBGENFS) && 1511 (!S_ISLNK(inode->i_mode) || 1512 selinux_policycap_genfs_seclabel_symlinks())) { 1513 /* We must have a dentry to determine the label on 1514 * procfs inodes */ 1515 if (opt_dentry) { 1516 /* Called from d_instantiate or 1517 * d_splice_alias. */ 1518 dentry = dget(opt_dentry); 1519 } else { 1520 /* Called from selinux_complete_init, try to 1521 * find a dentry. Some filesystems really want 1522 * a connected one, so try that first. 1523 */ 1524 dentry = d_find_alias(inode); 1525 if (!dentry) 1526 dentry = d_find_any_alias(inode); 1527 } 1528 /* 1529 * This can be hit on boot when a file is accessed 1530 * before the policy is loaded. When we load policy we 1531 * may find inodes that have no dentry on the 1532 * sbsec->isec_head list. No reason to complain as 1533 * these will get fixed up the next time we go through 1534 * inode_doinit() with a dentry, before these inodes 1535 * could be used again by userspace. 1536 */ 1537 if (!dentry) 1538 goto out_invalid; 1539 rc = selinux_genfs_get_sid(dentry, sclass, 1540 sbsec->flags, &sid); 1541 if (rc) { 1542 dput(dentry); 1543 goto out; 1544 } 1545 1546 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1547 (inode->i_opflags & IOP_XATTR)) { 1548 rc = inode_doinit_use_xattr(inode, dentry, 1549 sid, &sid); 1550 if (rc) { 1551 dput(dentry); 1552 goto out; 1553 } 1554 } 1555 dput(dentry); 1556 } 1557 break; 1558 } 1559 1560 out: 1561 spin_lock(&isec->lock); 1562 if (isec->initialized == LABEL_PENDING) { 1563 if (rc) { 1564 isec->initialized = LABEL_INVALID; 1565 goto out_unlock; 1566 } 1567 isec->initialized = LABEL_INITIALIZED; 1568 isec->sid = sid; 1569 } 1570 1571 out_unlock: 1572 spin_unlock(&isec->lock); 1573 return rc; 1574 1575 out_invalid: 1576 spin_lock(&isec->lock); 1577 if (isec->initialized == LABEL_PENDING) { 1578 isec->initialized = LABEL_INVALID; 1579 isec->sid = sid; 1580 } 1581 spin_unlock(&isec->lock); 1582 return 0; 1583 } 1584 1585 /* Convert a Linux signal to an access vector. */ 1586 static inline u32 signal_to_av(int sig) 1587 { 1588 u32 perm = 0; 1589 1590 switch (sig) { 1591 case SIGCHLD: 1592 /* Commonly granted from child to parent. */ 1593 perm = PROCESS__SIGCHLD; 1594 break; 1595 case SIGKILL: 1596 /* Cannot be caught or ignored */ 1597 perm = PROCESS__SIGKILL; 1598 break; 1599 case SIGSTOP: 1600 /* Cannot be caught or ignored */ 1601 perm = PROCESS__SIGSTOP; 1602 break; 1603 default: 1604 /* All other signals. */ 1605 perm = PROCESS__SIGNAL; 1606 break; 1607 } 1608 1609 return perm; 1610 } 1611 1612 #if CAP_LAST_CAP > 63 1613 #error Fix SELinux to handle capabilities > 63. 1614 #endif 1615 1616 /* Check whether a task is allowed to use a capability. */ 1617 static int cred_has_capability(const struct cred *cred, 1618 int cap, unsigned int opts, bool initns) 1619 { 1620 struct common_audit_data ad; 1621 struct av_decision avd; 1622 u16 sclass; 1623 u32 sid = cred_sid(cred); 1624 u32 av = CAP_TO_MASK(cap); 1625 int rc; 1626 1627 ad.type = LSM_AUDIT_DATA_CAP; 1628 ad.u.cap = cap; 1629 1630 switch (CAP_TO_INDEX(cap)) { 1631 case 0: 1632 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1633 break; 1634 case 1: 1635 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1636 break; 1637 default: 1638 pr_err("SELinux: out of range capability %d\n", cap); 1639 BUG(); 1640 return -EINVAL; 1641 } 1642 1643 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1644 if (!(opts & CAP_OPT_NOAUDIT)) { 1645 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1646 if (rc2) 1647 return rc2; 1648 } 1649 return rc; 1650 } 1651 1652 /* Check whether a task has a particular permission to an inode. 1653 The 'adp' parameter is optional and allows other audit 1654 data to be passed (e.g. the dentry). */ 1655 static int inode_has_perm(const struct cred *cred, 1656 struct inode *inode, 1657 u32 perms, 1658 struct common_audit_data *adp) 1659 { 1660 struct inode_security_struct *isec; 1661 u32 sid; 1662 1663 if (unlikely(IS_PRIVATE(inode))) 1664 return 0; 1665 1666 sid = cred_sid(cred); 1667 isec = selinux_inode(inode); 1668 1669 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1670 } 1671 1672 /* Same as inode_has_perm, but pass explicit audit data containing 1673 the dentry to help the auditing code to more easily generate the 1674 pathname if needed. */ 1675 static inline int dentry_has_perm(const struct cred *cred, 1676 struct dentry *dentry, 1677 u32 av) 1678 { 1679 struct inode *inode = d_backing_inode(dentry); 1680 struct common_audit_data ad; 1681 1682 ad.type = LSM_AUDIT_DATA_DENTRY; 1683 ad.u.dentry = dentry; 1684 __inode_security_revalidate(inode, dentry, true); 1685 return inode_has_perm(cred, inode, av, &ad); 1686 } 1687 1688 /* Same as inode_has_perm, but pass explicit audit data containing 1689 the path to help the auditing code to more easily generate the 1690 pathname if needed. */ 1691 static inline int path_has_perm(const struct cred *cred, 1692 const struct path *path, 1693 u32 av) 1694 { 1695 struct inode *inode = d_backing_inode(path->dentry); 1696 struct common_audit_data ad; 1697 1698 ad.type = LSM_AUDIT_DATA_PATH; 1699 ad.u.path = *path; 1700 __inode_security_revalidate(inode, path->dentry, true); 1701 return inode_has_perm(cred, inode, av, &ad); 1702 } 1703 1704 /* Same as path_has_perm, but uses the inode from the file struct. */ 1705 static inline int file_path_has_perm(const struct cred *cred, 1706 struct file *file, 1707 u32 av) 1708 { 1709 struct common_audit_data ad; 1710 1711 ad.type = LSM_AUDIT_DATA_FILE; 1712 ad.u.file = file; 1713 return inode_has_perm(cred, file_inode(file), av, &ad); 1714 } 1715 1716 #ifdef CONFIG_BPF_SYSCALL 1717 static int bpf_fd_pass(const struct file *file, u32 sid); 1718 #endif 1719 1720 /* Check whether a task can use an open file descriptor to 1721 access an inode in a given way. Check access to the 1722 descriptor itself, and then use dentry_has_perm to 1723 check a particular permission to the file. 1724 Access to the descriptor is implicitly granted if it 1725 has the same SID as the process. If av is zero, then 1726 access to the file is not checked, e.g. for cases 1727 where only the descriptor is affected like seek. */ 1728 static int file_has_perm(const struct cred *cred, 1729 struct file *file, 1730 u32 av) 1731 { 1732 struct file_security_struct *fsec = selinux_file(file); 1733 struct inode *inode = file_inode(file); 1734 struct common_audit_data ad; 1735 u32 sid = cred_sid(cred); 1736 int rc; 1737 1738 ad.type = LSM_AUDIT_DATA_FILE; 1739 ad.u.file = file; 1740 1741 if (sid != fsec->sid) { 1742 rc = avc_has_perm(sid, fsec->sid, 1743 SECCLASS_FD, 1744 FD__USE, 1745 &ad); 1746 if (rc) 1747 goto out; 1748 } 1749 1750 #ifdef CONFIG_BPF_SYSCALL 1751 rc = bpf_fd_pass(file, cred_sid(cred)); 1752 if (rc) 1753 return rc; 1754 #endif 1755 1756 /* av is zero if only checking access to the descriptor. */ 1757 rc = 0; 1758 if (av) 1759 rc = inode_has_perm(cred, inode, av, &ad); 1760 1761 out: 1762 return rc; 1763 } 1764 1765 /* 1766 * Determine the label for an inode that might be unioned. 1767 */ 1768 static int 1769 selinux_determine_inode_label(const struct task_security_struct *tsec, 1770 struct inode *dir, 1771 const struct qstr *name, u16 tclass, 1772 u32 *_new_isid) 1773 { 1774 const struct superblock_security_struct *sbsec = 1775 selinux_superblock(dir->i_sb); 1776 1777 if ((sbsec->flags & SE_SBINITIALIZED) && 1778 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1779 *_new_isid = sbsec->mntpoint_sid; 1780 } else if ((sbsec->flags & SBLABEL_MNT) && 1781 tsec->create_sid) { 1782 *_new_isid = tsec->create_sid; 1783 } else { 1784 const struct inode_security_struct *dsec = inode_security(dir); 1785 return security_transition_sid(tsec->sid, 1786 dsec->sid, tclass, 1787 name, _new_isid); 1788 } 1789 1790 return 0; 1791 } 1792 1793 /* Check whether a task can create a file. */ 1794 static int may_create(struct inode *dir, 1795 struct dentry *dentry, 1796 u16 tclass) 1797 { 1798 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1799 struct inode_security_struct *dsec; 1800 struct superblock_security_struct *sbsec; 1801 u32 sid, newsid; 1802 struct common_audit_data ad; 1803 int rc; 1804 1805 dsec = inode_security(dir); 1806 sbsec = selinux_superblock(dir->i_sb); 1807 1808 sid = tsec->sid; 1809 1810 ad.type = LSM_AUDIT_DATA_DENTRY; 1811 ad.u.dentry = dentry; 1812 1813 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1814 DIR__ADD_NAME | DIR__SEARCH, 1815 &ad); 1816 if (rc) 1817 return rc; 1818 1819 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1820 &newsid); 1821 if (rc) 1822 return rc; 1823 1824 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1825 if (rc) 1826 return rc; 1827 1828 return avc_has_perm(newsid, sbsec->sid, 1829 SECCLASS_FILESYSTEM, 1830 FILESYSTEM__ASSOCIATE, &ad); 1831 } 1832 1833 #define MAY_LINK 0 1834 #define MAY_UNLINK 1 1835 #define MAY_RMDIR 2 1836 1837 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1838 static int may_link(struct inode *dir, 1839 struct dentry *dentry, 1840 int kind) 1841 1842 { 1843 struct inode_security_struct *dsec, *isec; 1844 struct common_audit_data ad; 1845 u32 sid = current_sid(); 1846 u32 av; 1847 int rc; 1848 1849 dsec = inode_security(dir); 1850 isec = backing_inode_security(dentry); 1851 1852 ad.type = LSM_AUDIT_DATA_DENTRY; 1853 ad.u.dentry = dentry; 1854 1855 av = DIR__SEARCH; 1856 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1857 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1858 if (rc) 1859 return rc; 1860 1861 switch (kind) { 1862 case MAY_LINK: 1863 av = FILE__LINK; 1864 break; 1865 case MAY_UNLINK: 1866 av = FILE__UNLINK; 1867 break; 1868 case MAY_RMDIR: 1869 av = DIR__RMDIR; 1870 break; 1871 default: 1872 pr_warn("SELinux: %s: unrecognized kind %d\n", 1873 __func__, kind); 1874 return 0; 1875 } 1876 1877 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1878 return rc; 1879 } 1880 1881 static inline int may_rename(struct inode *old_dir, 1882 struct dentry *old_dentry, 1883 struct inode *new_dir, 1884 struct dentry *new_dentry) 1885 { 1886 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1887 struct common_audit_data ad; 1888 u32 sid = current_sid(); 1889 u32 av; 1890 int old_is_dir, new_is_dir; 1891 int rc; 1892 1893 old_dsec = inode_security(old_dir); 1894 old_isec = backing_inode_security(old_dentry); 1895 old_is_dir = d_is_dir(old_dentry); 1896 new_dsec = inode_security(new_dir); 1897 1898 ad.type = LSM_AUDIT_DATA_DENTRY; 1899 1900 ad.u.dentry = old_dentry; 1901 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1902 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1903 if (rc) 1904 return rc; 1905 rc = avc_has_perm(sid, old_isec->sid, 1906 old_isec->sclass, FILE__RENAME, &ad); 1907 if (rc) 1908 return rc; 1909 if (old_is_dir && new_dir != old_dir) { 1910 rc = avc_has_perm(sid, old_isec->sid, 1911 old_isec->sclass, DIR__REPARENT, &ad); 1912 if (rc) 1913 return rc; 1914 } 1915 1916 ad.u.dentry = new_dentry; 1917 av = DIR__ADD_NAME | DIR__SEARCH; 1918 if (d_is_positive(new_dentry)) 1919 av |= DIR__REMOVE_NAME; 1920 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1921 if (rc) 1922 return rc; 1923 if (d_is_positive(new_dentry)) { 1924 new_isec = backing_inode_security(new_dentry); 1925 new_is_dir = d_is_dir(new_dentry); 1926 rc = avc_has_perm(sid, new_isec->sid, 1927 new_isec->sclass, 1928 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1929 if (rc) 1930 return rc; 1931 } 1932 1933 return 0; 1934 } 1935 1936 /* Check whether a task can perform a filesystem operation. */ 1937 static int superblock_has_perm(const struct cred *cred, 1938 struct super_block *sb, 1939 u32 perms, 1940 struct common_audit_data *ad) 1941 { 1942 struct superblock_security_struct *sbsec; 1943 u32 sid = cred_sid(cred); 1944 1945 sbsec = selinux_superblock(sb); 1946 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1947 } 1948 1949 /* Convert a Linux mode and permission mask to an access vector. */ 1950 static inline u32 file_mask_to_av(int mode, int mask) 1951 { 1952 u32 av = 0; 1953 1954 if (!S_ISDIR(mode)) { 1955 if (mask & MAY_EXEC) 1956 av |= FILE__EXECUTE; 1957 if (mask & MAY_READ) 1958 av |= FILE__READ; 1959 1960 if (mask & MAY_APPEND) 1961 av |= FILE__APPEND; 1962 else if (mask & MAY_WRITE) 1963 av |= FILE__WRITE; 1964 1965 } else { 1966 if (mask & MAY_EXEC) 1967 av |= DIR__SEARCH; 1968 if (mask & MAY_WRITE) 1969 av |= DIR__WRITE; 1970 if (mask & MAY_READ) 1971 av |= DIR__READ; 1972 } 1973 1974 return av; 1975 } 1976 1977 /* Convert a Linux file to an access vector. */ 1978 static inline u32 file_to_av(const struct file *file) 1979 { 1980 u32 av = 0; 1981 1982 if (file->f_mode & FMODE_READ) 1983 av |= FILE__READ; 1984 if (file->f_mode & FMODE_WRITE) { 1985 if (file->f_flags & O_APPEND) 1986 av |= FILE__APPEND; 1987 else 1988 av |= FILE__WRITE; 1989 } 1990 if (!av) { 1991 /* 1992 * Special file opened with flags 3 for ioctl-only use. 1993 */ 1994 av = FILE__IOCTL; 1995 } 1996 1997 return av; 1998 } 1999 2000 /* 2001 * Convert a file to an access vector and include the correct 2002 * open permission. 2003 */ 2004 static inline u32 open_file_to_av(struct file *file) 2005 { 2006 u32 av = file_to_av(file); 2007 struct inode *inode = file_inode(file); 2008 2009 if (selinux_policycap_openperm() && 2010 inode->i_sb->s_magic != SOCKFS_MAGIC) 2011 av |= FILE__OPEN; 2012 2013 return av; 2014 } 2015 2016 /* Hook functions begin here. */ 2017 2018 static int selinux_binder_set_context_mgr(const struct cred *mgr) 2019 { 2020 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, 2021 BINDER__SET_CONTEXT_MGR, NULL); 2022 } 2023 2024 static int selinux_binder_transaction(const struct cred *from, 2025 const struct cred *to) 2026 { 2027 u32 mysid = current_sid(); 2028 u32 fromsid = cred_sid(from); 2029 u32 tosid = cred_sid(to); 2030 int rc; 2031 2032 if (mysid != fromsid) { 2033 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2034 BINDER__IMPERSONATE, NULL); 2035 if (rc) 2036 return rc; 2037 } 2038 2039 return avc_has_perm(fromsid, tosid, 2040 SECCLASS_BINDER, BINDER__CALL, NULL); 2041 } 2042 2043 static int selinux_binder_transfer_binder(const struct cred *from, 2044 const struct cred *to) 2045 { 2046 return avc_has_perm(cred_sid(from), cred_sid(to), 2047 SECCLASS_BINDER, BINDER__TRANSFER, 2048 NULL); 2049 } 2050 2051 static int selinux_binder_transfer_file(const struct cred *from, 2052 const struct cred *to, 2053 const struct file *file) 2054 { 2055 u32 sid = cred_sid(to); 2056 struct file_security_struct *fsec = selinux_file(file); 2057 struct dentry *dentry = file->f_path.dentry; 2058 struct inode_security_struct *isec; 2059 struct common_audit_data ad; 2060 int rc; 2061 2062 ad.type = LSM_AUDIT_DATA_PATH; 2063 ad.u.path = file->f_path; 2064 2065 if (sid != fsec->sid) { 2066 rc = avc_has_perm(sid, fsec->sid, 2067 SECCLASS_FD, 2068 FD__USE, 2069 &ad); 2070 if (rc) 2071 return rc; 2072 } 2073 2074 #ifdef CONFIG_BPF_SYSCALL 2075 rc = bpf_fd_pass(file, sid); 2076 if (rc) 2077 return rc; 2078 #endif 2079 2080 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2081 return 0; 2082 2083 isec = backing_inode_security(dentry); 2084 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2085 &ad); 2086 } 2087 2088 static int selinux_ptrace_access_check(struct task_struct *child, 2089 unsigned int mode) 2090 { 2091 u32 sid = current_sid(); 2092 u32 csid = task_sid_obj(child); 2093 2094 if (mode & PTRACE_MODE_READ) 2095 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, 2096 NULL); 2097 2098 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, 2099 NULL); 2100 } 2101 2102 static int selinux_ptrace_traceme(struct task_struct *parent) 2103 { 2104 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), 2105 SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2106 } 2107 2108 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, 2109 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2110 { 2111 return avc_has_perm(current_sid(), task_sid_obj(target), 2112 SECCLASS_PROCESS, PROCESS__GETCAP, NULL); 2113 } 2114 2115 static int selinux_capset(struct cred *new, const struct cred *old, 2116 const kernel_cap_t *effective, 2117 const kernel_cap_t *inheritable, 2118 const kernel_cap_t *permitted) 2119 { 2120 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2121 PROCESS__SETCAP, NULL); 2122 } 2123 2124 /* 2125 * (This comment used to live with the selinux_task_setuid hook, 2126 * which was removed). 2127 * 2128 * Since setuid only affects the current process, and since the SELinux 2129 * controls are not based on the Linux identity attributes, SELinux does not 2130 * need to control this operation. However, SELinux does control the use of 2131 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2132 */ 2133 2134 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2135 int cap, unsigned int opts) 2136 { 2137 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2138 } 2139 2140 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2141 { 2142 const struct cred *cred = current_cred(); 2143 int rc = 0; 2144 2145 if (!sb) 2146 return 0; 2147 2148 switch (cmds) { 2149 case Q_SYNC: 2150 case Q_QUOTAON: 2151 case Q_QUOTAOFF: 2152 case Q_SETINFO: 2153 case Q_SETQUOTA: 2154 case Q_XQUOTAOFF: 2155 case Q_XQUOTAON: 2156 case Q_XSETQLIM: 2157 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2158 break; 2159 case Q_GETFMT: 2160 case Q_GETINFO: 2161 case Q_GETQUOTA: 2162 case Q_XGETQUOTA: 2163 case Q_XGETQSTAT: 2164 case Q_XGETQSTATV: 2165 case Q_XGETNEXTQUOTA: 2166 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2167 break; 2168 default: 2169 rc = 0; /* let the kernel handle invalid cmds */ 2170 break; 2171 } 2172 return rc; 2173 } 2174 2175 static int selinux_quota_on(struct dentry *dentry) 2176 { 2177 const struct cred *cred = current_cred(); 2178 2179 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2180 } 2181 2182 static int selinux_syslog(int type) 2183 { 2184 switch (type) { 2185 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2186 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2187 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2188 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2189 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2190 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2191 /* Set level of messages printed to console */ 2192 case SYSLOG_ACTION_CONSOLE_LEVEL: 2193 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2194 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2195 NULL); 2196 } 2197 /* All other syslog types */ 2198 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2199 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2200 } 2201 2202 /* 2203 * Check that a process has enough memory to allocate a new virtual 2204 * mapping. 0 means there is enough memory for the allocation to 2205 * succeed and -ENOMEM implies there is not. 2206 * 2207 * Do not audit the selinux permission check, as this is applied to all 2208 * processes that allocate mappings. 2209 */ 2210 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2211 { 2212 int rc, cap_sys_admin = 0; 2213 2214 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2215 CAP_OPT_NOAUDIT, true); 2216 if (rc == 0) 2217 cap_sys_admin = 1; 2218 2219 return cap_sys_admin; 2220 } 2221 2222 /* binprm security operations */ 2223 2224 static u32 ptrace_parent_sid(void) 2225 { 2226 u32 sid = 0; 2227 struct task_struct *tracer; 2228 2229 rcu_read_lock(); 2230 tracer = ptrace_parent(current); 2231 if (tracer) 2232 sid = task_sid_obj(tracer); 2233 rcu_read_unlock(); 2234 2235 return sid; 2236 } 2237 2238 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2239 const struct task_security_struct *old_tsec, 2240 const struct task_security_struct *new_tsec) 2241 { 2242 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2243 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2244 int rc; 2245 u32 av; 2246 2247 if (!nnp && !nosuid) 2248 return 0; /* neither NNP nor nosuid */ 2249 2250 if (new_tsec->sid == old_tsec->sid) 2251 return 0; /* No change in credentials */ 2252 2253 /* 2254 * If the policy enables the nnp_nosuid_transition policy capability, 2255 * then we permit transitions under NNP or nosuid if the 2256 * policy allows the corresponding permission between 2257 * the old and new contexts. 2258 */ 2259 if (selinux_policycap_nnp_nosuid_transition()) { 2260 av = 0; 2261 if (nnp) 2262 av |= PROCESS2__NNP_TRANSITION; 2263 if (nosuid) 2264 av |= PROCESS2__NOSUID_TRANSITION; 2265 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2266 SECCLASS_PROCESS2, av, NULL); 2267 if (!rc) 2268 return 0; 2269 } 2270 2271 /* 2272 * We also permit NNP or nosuid transitions to bounded SIDs, 2273 * i.e. SIDs that are guaranteed to only be allowed a subset 2274 * of the permissions of the current SID. 2275 */ 2276 rc = security_bounded_transition(old_tsec->sid, 2277 new_tsec->sid); 2278 if (!rc) 2279 return 0; 2280 2281 /* 2282 * On failure, preserve the errno values for NNP vs nosuid. 2283 * NNP: Operation not permitted for caller. 2284 * nosuid: Permission denied to file. 2285 */ 2286 if (nnp) 2287 return -EPERM; 2288 return -EACCES; 2289 } 2290 2291 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2292 { 2293 const struct task_security_struct *old_tsec; 2294 struct task_security_struct *new_tsec; 2295 struct inode_security_struct *isec; 2296 struct common_audit_data ad; 2297 struct inode *inode = file_inode(bprm->file); 2298 int rc; 2299 2300 /* SELinux context only depends on initial program or script and not 2301 * the script interpreter */ 2302 2303 old_tsec = selinux_cred(current_cred()); 2304 new_tsec = selinux_cred(bprm->cred); 2305 isec = inode_security(inode); 2306 2307 /* Default to the current task SID. */ 2308 new_tsec->sid = old_tsec->sid; 2309 new_tsec->osid = old_tsec->sid; 2310 2311 /* Reset fs, key, and sock SIDs on execve. */ 2312 new_tsec->create_sid = 0; 2313 new_tsec->keycreate_sid = 0; 2314 new_tsec->sockcreate_sid = 0; 2315 2316 if (old_tsec->exec_sid) { 2317 new_tsec->sid = old_tsec->exec_sid; 2318 /* Reset exec SID on execve. */ 2319 new_tsec->exec_sid = 0; 2320 2321 /* Fail on NNP or nosuid if not an allowed transition. */ 2322 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2323 if (rc) 2324 return rc; 2325 } else { 2326 /* Check for a default transition on this program. */ 2327 rc = security_transition_sid(old_tsec->sid, 2328 isec->sid, SECCLASS_PROCESS, NULL, 2329 &new_tsec->sid); 2330 if (rc) 2331 return rc; 2332 2333 /* 2334 * Fallback to old SID on NNP or nosuid if not an allowed 2335 * transition. 2336 */ 2337 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2338 if (rc) 2339 new_tsec->sid = old_tsec->sid; 2340 } 2341 2342 ad.type = LSM_AUDIT_DATA_FILE; 2343 ad.u.file = bprm->file; 2344 2345 if (new_tsec->sid == old_tsec->sid) { 2346 rc = avc_has_perm(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(old_tsec->sid, new_tsec->sid, 2353 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2354 if (rc) 2355 return rc; 2356 2357 rc = avc_has_perm(new_tsec->sid, isec->sid, 2358 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2359 if (rc) 2360 return rc; 2361 2362 /* Check for shared state */ 2363 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2364 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2365 SECCLASS_PROCESS, PROCESS__SHARE, 2366 NULL); 2367 if (rc) 2368 return -EPERM; 2369 } 2370 2371 /* Make sure that anyone attempting to ptrace over a task that 2372 * changes its SID has the appropriate permit */ 2373 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2374 u32 ptsid = ptrace_parent_sid(); 2375 if (ptsid != 0) { 2376 rc = avc_has_perm(ptsid, new_tsec->sid, 2377 SECCLASS_PROCESS, 2378 PROCESS__PTRACE, NULL); 2379 if (rc) 2380 return -EPERM; 2381 } 2382 } 2383 2384 /* Clear any possibly unsafe personality bits on exec: */ 2385 bprm->per_clear |= PER_CLEAR_ON_SETID; 2386 2387 /* Enable secure mode for SIDs transitions unless 2388 the noatsecure permission is granted between 2389 the two SIDs, i.e. ahp returns 0. */ 2390 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2391 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2392 NULL); 2393 bprm->secureexec |= !!rc; 2394 } 2395 2396 return 0; 2397 } 2398 2399 static int match_file(const void *p, struct file *file, unsigned fd) 2400 { 2401 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2402 } 2403 2404 /* Derived from fs/exec.c:flush_old_files. */ 2405 static inline void flush_unauthorized_files(const struct cred *cred, 2406 struct files_struct *files) 2407 { 2408 struct file *file, *devnull = NULL; 2409 struct tty_struct *tty; 2410 int drop_tty = 0; 2411 unsigned n; 2412 2413 tty = get_current_tty(); 2414 if (tty) { 2415 spin_lock(&tty->files_lock); 2416 if (!list_empty(&tty->tty_files)) { 2417 struct tty_file_private *file_priv; 2418 2419 /* Revalidate access to controlling tty. 2420 Use file_path_has_perm on the tty path directly 2421 rather than using file_has_perm, as this particular 2422 open file may belong to another process and we are 2423 only interested in the inode-based check here. */ 2424 file_priv = list_first_entry(&tty->tty_files, 2425 struct tty_file_private, list); 2426 file = file_priv->file; 2427 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2428 drop_tty = 1; 2429 } 2430 spin_unlock(&tty->files_lock); 2431 tty_kref_put(tty); 2432 } 2433 /* Reset controlling tty. */ 2434 if (drop_tty) 2435 no_tty(); 2436 2437 /* Revalidate access to inherited open files. */ 2438 n = iterate_fd(files, 0, match_file, cred); 2439 if (!n) /* none found? */ 2440 return; 2441 2442 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2443 if (IS_ERR(devnull)) 2444 devnull = NULL; 2445 /* replace all the matching ones with this */ 2446 do { 2447 replace_fd(n - 1, devnull, 0); 2448 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2449 if (devnull) 2450 fput(devnull); 2451 } 2452 2453 /* 2454 * Prepare a process for imminent new credential changes due to exec 2455 */ 2456 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2457 { 2458 struct task_security_struct *new_tsec; 2459 struct rlimit *rlim, *initrlim; 2460 int rc, i; 2461 2462 new_tsec = selinux_cred(bprm->cred); 2463 if (new_tsec->sid == new_tsec->osid) 2464 return; 2465 2466 /* Close files for which the new task SID is not authorized. */ 2467 flush_unauthorized_files(bprm->cred, current->files); 2468 2469 /* Always clear parent death signal on SID transitions. */ 2470 current->pdeath_signal = 0; 2471 2472 /* Check whether the new SID can inherit resource limits from the old 2473 * SID. If not, reset all soft limits to the lower of the current 2474 * task's hard limit and the init task's soft limit. 2475 * 2476 * Note that the setting of hard limits (even to lower them) can be 2477 * controlled by the setrlimit check. The inclusion of the init task's 2478 * soft limit into the computation is to avoid resetting soft limits 2479 * higher than the default soft limit for cases where the default is 2480 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2481 */ 2482 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2483 PROCESS__RLIMITINH, NULL); 2484 if (rc) { 2485 /* protect against do_prlimit() */ 2486 task_lock(current); 2487 for (i = 0; i < RLIM_NLIMITS; i++) { 2488 rlim = current->signal->rlim + i; 2489 initrlim = init_task.signal->rlim + i; 2490 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2491 } 2492 task_unlock(current); 2493 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2494 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2495 } 2496 } 2497 2498 /* 2499 * Clean up the process immediately after the installation of new credentials 2500 * due to exec 2501 */ 2502 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2503 { 2504 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2505 u32 osid, sid; 2506 int rc; 2507 2508 osid = tsec->osid; 2509 sid = tsec->sid; 2510 2511 if (sid == osid) 2512 return; 2513 2514 /* Check whether the new SID can inherit signal state from the old SID. 2515 * If not, clear itimers to avoid subsequent signal generation and 2516 * flush and unblock signals. 2517 * 2518 * This must occur _after_ the task SID has been updated so that any 2519 * kill done after the flush will be checked against the new SID. 2520 */ 2521 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2522 if (rc) { 2523 clear_itimer(); 2524 2525 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); 2526 if (!fatal_signal_pending(current)) { 2527 flush_sigqueue(¤t->pending); 2528 flush_sigqueue(¤t->signal->shared_pending); 2529 flush_signal_handlers(current, 1); 2530 sigemptyset(¤t->blocked); 2531 recalc_sigpending(); 2532 } 2533 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); 2534 } 2535 2536 /* Wake up the parent if it is waiting so that it can recheck 2537 * wait permission to the new task SID. */ 2538 read_lock(&tasklist_lock); 2539 __wake_up_parent(current, unrcu_pointer(current->real_parent)); 2540 read_unlock(&tasklist_lock); 2541 } 2542 2543 /* superblock security operations */ 2544 2545 static int selinux_sb_alloc_security(struct super_block *sb) 2546 { 2547 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2548 2549 mutex_init(&sbsec->lock); 2550 INIT_LIST_HEAD(&sbsec->isec_head); 2551 spin_lock_init(&sbsec->isec_lock); 2552 sbsec->sid = SECINITSID_UNLABELED; 2553 sbsec->def_sid = SECINITSID_FILE; 2554 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2555 2556 return 0; 2557 } 2558 2559 static inline int opt_len(const char *s) 2560 { 2561 bool open_quote = false; 2562 int len; 2563 char c; 2564 2565 for (len = 0; (c = s[len]) != '\0'; len++) { 2566 if (c == '"') 2567 open_quote = !open_quote; 2568 if (c == ',' && !open_quote) 2569 break; 2570 } 2571 return len; 2572 } 2573 2574 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2575 { 2576 char *from = options; 2577 char *to = options; 2578 bool first = true; 2579 int rc; 2580 2581 while (1) { 2582 int len = opt_len(from); 2583 int token; 2584 char *arg = NULL; 2585 2586 token = match_opt_prefix(from, len, &arg); 2587 2588 if (token != Opt_error) { 2589 char *p, *q; 2590 2591 /* strip quotes */ 2592 if (arg) { 2593 for (p = q = arg; p < from + len; p++) { 2594 char c = *p; 2595 if (c != '"') 2596 *q++ = c; 2597 } 2598 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2599 if (!arg) { 2600 rc = -ENOMEM; 2601 goto free_opt; 2602 } 2603 } 2604 rc = selinux_add_opt(token, arg, mnt_opts); 2605 kfree(arg); 2606 arg = NULL; 2607 if (unlikely(rc)) { 2608 goto free_opt; 2609 } 2610 } else { 2611 if (!first) { // copy with preceding comma 2612 from--; 2613 len++; 2614 } 2615 if (to != from) 2616 memmove(to, from, len); 2617 to += len; 2618 first = false; 2619 } 2620 if (!from[len]) 2621 break; 2622 from += len + 1; 2623 } 2624 *to = '\0'; 2625 return 0; 2626 2627 free_opt: 2628 if (*mnt_opts) { 2629 selinux_free_mnt_opts(*mnt_opts); 2630 *mnt_opts = NULL; 2631 } 2632 return rc; 2633 } 2634 2635 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2636 { 2637 struct selinux_mnt_opts *opts = mnt_opts; 2638 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2639 2640 /* 2641 * Superblock not initialized (i.e. no options) - reject if any 2642 * options specified, otherwise accept. 2643 */ 2644 if (!(sbsec->flags & SE_SBINITIALIZED)) 2645 return opts ? 1 : 0; 2646 2647 /* 2648 * Superblock initialized and no options specified - reject if 2649 * superblock has any options set, otherwise accept. 2650 */ 2651 if (!opts) 2652 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2653 2654 if (opts->fscontext_sid) { 2655 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2656 opts->fscontext_sid)) 2657 return 1; 2658 } 2659 if (opts->context_sid) { 2660 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2661 opts->context_sid)) 2662 return 1; 2663 } 2664 if (opts->rootcontext_sid) { 2665 struct inode_security_struct *root_isec; 2666 2667 root_isec = backing_inode_security(sb->s_root); 2668 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2669 opts->rootcontext_sid)) 2670 return 1; 2671 } 2672 if (opts->defcontext_sid) { 2673 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2674 opts->defcontext_sid)) 2675 return 1; 2676 } 2677 return 0; 2678 } 2679 2680 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2681 { 2682 struct selinux_mnt_opts *opts = mnt_opts; 2683 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2684 2685 if (!(sbsec->flags & SE_SBINITIALIZED)) 2686 return 0; 2687 2688 if (!opts) 2689 return 0; 2690 2691 if (opts->fscontext_sid) { 2692 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2693 opts->fscontext_sid)) 2694 goto out_bad_option; 2695 } 2696 if (opts->context_sid) { 2697 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2698 opts->context_sid)) 2699 goto out_bad_option; 2700 } 2701 if (opts->rootcontext_sid) { 2702 struct inode_security_struct *root_isec; 2703 root_isec = backing_inode_security(sb->s_root); 2704 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2705 opts->rootcontext_sid)) 2706 goto out_bad_option; 2707 } 2708 if (opts->defcontext_sid) { 2709 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2710 opts->defcontext_sid)) 2711 goto out_bad_option; 2712 } 2713 return 0; 2714 2715 out_bad_option: 2716 pr_warn("SELinux: unable to change security options " 2717 "during remount (dev %s, type=%s)\n", sb->s_id, 2718 sb->s_type->name); 2719 return -EINVAL; 2720 } 2721 2722 static int selinux_sb_kern_mount(struct super_block *sb) 2723 { 2724 const struct cred *cred = current_cred(); 2725 struct common_audit_data ad; 2726 2727 ad.type = LSM_AUDIT_DATA_DENTRY; 2728 ad.u.dentry = sb->s_root; 2729 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2730 } 2731 2732 static int selinux_sb_statfs(struct dentry *dentry) 2733 { 2734 const struct cred *cred = current_cred(); 2735 struct common_audit_data ad; 2736 2737 ad.type = LSM_AUDIT_DATA_DENTRY; 2738 ad.u.dentry = dentry->d_sb->s_root; 2739 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2740 } 2741 2742 static int selinux_mount(const char *dev_name, 2743 const struct path *path, 2744 const char *type, 2745 unsigned long flags, 2746 void *data) 2747 { 2748 const struct cred *cred = current_cred(); 2749 2750 if (flags & MS_REMOUNT) 2751 return superblock_has_perm(cred, path->dentry->d_sb, 2752 FILESYSTEM__REMOUNT, NULL); 2753 else 2754 return path_has_perm(cred, path, FILE__MOUNTON); 2755 } 2756 2757 static int selinux_move_mount(const struct path *from_path, 2758 const struct path *to_path) 2759 { 2760 const struct cred *cred = current_cred(); 2761 2762 return path_has_perm(cred, to_path, FILE__MOUNTON); 2763 } 2764 2765 static int selinux_umount(struct vfsmount *mnt, int flags) 2766 { 2767 const struct cred *cred = current_cred(); 2768 2769 return superblock_has_perm(cred, mnt->mnt_sb, 2770 FILESYSTEM__UNMOUNT, NULL); 2771 } 2772 2773 static int selinux_fs_context_submount(struct fs_context *fc, 2774 struct super_block *reference) 2775 { 2776 const struct superblock_security_struct *sbsec = selinux_superblock(reference); 2777 struct selinux_mnt_opts *opts; 2778 2779 /* 2780 * Ensure that fc->security remains NULL when no options are set 2781 * as expected by selinux_set_mnt_opts(). 2782 */ 2783 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) 2784 return 0; 2785 2786 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 2787 if (!opts) 2788 return -ENOMEM; 2789 2790 if (sbsec->flags & FSCONTEXT_MNT) 2791 opts->fscontext_sid = sbsec->sid; 2792 if (sbsec->flags & CONTEXT_MNT) 2793 opts->context_sid = sbsec->mntpoint_sid; 2794 if (sbsec->flags & DEFCONTEXT_MNT) 2795 opts->defcontext_sid = sbsec->def_sid; 2796 fc->security = opts; 2797 return 0; 2798 } 2799 2800 static int selinux_fs_context_dup(struct fs_context *fc, 2801 struct fs_context *src_fc) 2802 { 2803 const struct selinux_mnt_opts *src = src_fc->security; 2804 2805 if (!src) 2806 return 0; 2807 2808 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); 2809 return fc->security ? 0 : -ENOMEM; 2810 } 2811 2812 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2813 fsparam_string(CONTEXT_STR, Opt_context), 2814 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2815 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2816 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2817 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2818 {} 2819 }; 2820 2821 static int selinux_fs_context_parse_param(struct fs_context *fc, 2822 struct fs_parameter *param) 2823 { 2824 struct fs_parse_result result; 2825 int opt; 2826 2827 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2828 if (opt < 0) 2829 return opt; 2830 2831 return selinux_add_opt(opt, param->string, &fc->security); 2832 } 2833 2834 /* inode security operations */ 2835 2836 static int selinux_inode_alloc_security(struct inode *inode) 2837 { 2838 struct inode_security_struct *isec = selinux_inode(inode); 2839 u32 sid = current_sid(); 2840 2841 spin_lock_init(&isec->lock); 2842 INIT_LIST_HEAD(&isec->list); 2843 isec->inode = inode; 2844 isec->sid = SECINITSID_UNLABELED; 2845 isec->sclass = SECCLASS_FILE; 2846 isec->task_sid = sid; 2847 isec->initialized = LABEL_INVALID; 2848 2849 return 0; 2850 } 2851 2852 static void selinux_inode_free_security(struct inode *inode) 2853 { 2854 inode_free_security(inode); 2855 } 2856 2857 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2858 const struct qstr *name, 2859 const char **xattr_name, void **ctx, 2860 u32 *ctxlen) 2861 { 2862 u32 newsid; 2863 int rc; 2864 2865 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2866 d_inode(dentry->d_parent), name, 2867 inode_mode_to_security_class(mode), 2868 &newsid); 2869 if (rc) 2870 return rc; 2871 2872 if (xattr_name) 2873 *xattr_name = XATTR_NAME_SELINUX; 2874 2875 return security_sid_to_context(newsid, (char **)ctx, 2876 ctxlen); 2877 } 2878 2879 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2880 struct qstr *name, 2881 const struct cred *old, 2882 struct cred *new) 2883 { 2884 u32 newsid; 2885 int rc; 2886 struct task_security_struct *tsec; 2887 2888 rc = selinux_determine_inode_label(selinux_cred(old), 2889 d_inode(dentry->d_parent), name, 2890 inode_mode_to_security_class(mode), 2891 &newsid); 2892 if (rc) 2893 return rc; 2894 2895 tsec = selinux_cred(new); 2896 tsec->create_sid = newsid; 2897 return 0; 2898 } 2899 2900 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2901 const struct qstr *qstr, 2902 struct xattr *xattrs, int *xattr_count) 2903 { 2904 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2905 struct superblock_security_struct *sbsec; 2906 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); 2907 u32 newsid, clen; 2908 int rc; 2909 char *context; 2910 2911 sbsec = selinux_superblock(dir->i_sb); 2912 2913 newsid = tsec->create_sid; 2914 2915 rc = selinux_determine_inode_label(tsec, dir, qstr, 2916 inode_mode_to_security_class(inode->i_mode), 2917 &newsid); 2918 if (rc) 2919 return rc; 2920 2921 /* Possibly defer initialization to selinux_complete_init. */ 2922 if (sbsec->flags & SE_SBINITIALIZED) { 2923 struct inode_security_struct *isec = selinux_inode(inode); 2924 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2925 isec->sid = newsid; 2926 isec->initialized = LABEL_INITIALIZED; 2927 } 2928 2929 if (!selinux_initialized() || 2930 !(sbsec->flags & SBLABEL_MNT)) 2931 return -EOPNOTSUPP; 2932 2933 if (xattr) { 2934 rc = security_sid_to_context_force(newsid, 2935 &context, &clen); 2936 if (rc) 2937 return rc; 2938 xattr->value = context; 2939 xattr->value_len = clen; 2940 xattr->name = XATTR_SELINUX_SUFFIX; 2941 } 2942 2943 return 0; 2944 } 2945 2946 static int selinux_inode_init_security_anon(struct inode *inode, 2947 const struct qstr *name, 2948 const struct inode *context_inode) 2949 { 2950 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2951 struct common_audit_data ad; 2952 struct inode_security_struct *isec; 2953 int rc; 2954 2955 if (unlikely(!selinux_initialized())) 2956 return 0; 2957 2958 isec = selinux_inode(inode); 2959 2960 /* 2961 * We only get here once per ephemeral inode. The inode has 2962 * been initialized via inode_alloc_security but is otherwise 2963 * untouched. 2964 */ 2965 2966 if (context_inode) { 2967 struct inode_security_struct *context_isec = 2968 selinux_inode(context_inode); 2969 if (context_isec->initialized != LABEL_INITIALIZED) { 2970 pr_err("SELinux: context_inode is not initialized\n"); 2971 return -EACCES; 2972 } 2973 2974 isec->sclass = context_isec->sclass; 2975 isec->sid = context_isec->sid; 2976 } else { 2977 isec->sclass = SECCLASS_ANON_INODE; 2978 rc = security_transition_sid( 2979 tsec->sid, tsec->sid, 2980 isec->sclass, name, &isec->sid); 2981 if (rc) 2982 return rc; 2983 } 2984 2985 isec->initialized = LABEL_INITIALIZED; 2986 /* 2987 * Now that we've initialized security, check whether we're 2988 * allowed to actually create this type of anonymous inode. 2989 */ 2990 2991 ad.type = LSM_AUDIT_DATA_ANONINODE; 2992 ad.u.anonclass = name ? (const char *)name->name : "?"; 2993 2994 return avc_has_perm(tsec->sid, 2995 isec->sid, 2996 isec->sclass, 2997 FILE__CREATE, 2998 &ad); 2999 } 3000 3001 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3002 { 3003 return may_create(dir, dentry, SECCLASS_FILE); 3004 } 3005 3006 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3007 { 3008 return may_link(dir, old_dentry, MAY_LINK); 3009 } 3010 3011 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3012 { 3013 return may_link(dir, dentry, MAY_UNLINK); 3014 } 3015 3016 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3017 { 3018 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3019 } 3020 3021 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3022 { 3023 return may_create(dir, dentry, SECCLASS_DIR); 3024 } 3025 3026 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3027 { 3028 return may_link(dir, dentry, MAY_RMDIR); 3029 } 3030 3031 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3032 { 3033 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3034 } 3035 3036 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3037 struct inode *new_inode, struct dentry *new_dentry) 3038 { 3039 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3040 } 3041 3042 static int selinux_inode_readlink(struct dentry *dentry) 3043 { 3044 const struct cred *cred = current_cred(); 3045 3046 return dentry_has_perm(cred, dentry, FILE__READ); 3047 } 3048 3049 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3050 bool rcu) 3051 { 3052 const struct cred *cred = current_cred(); 3053 struct common_audit_data ad; 3054 struct inode_security_struct *isec; 3055 u32 sid; 3056 3057 ad.type = LSM_AUDIT_DATA_DENTRY; 3058 ad.u.dentry = dentry; 3059 sid = cred_sid(cred); 3060 isec = inode_security_rcu(inode, rcu); 3061 if (IS_ERR(isec)) 3062 return PTR_ERR(isec); 3063 3064 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); 3065 } 3066 3067 static noinline int audit_inode_permission(struct inode *inode, 3068 u32 perms, u32 audited, u32 denied, 3069 int result) 3070 { 3071 struct common_audit_data ad; 3072 struct inode_security_struct *isec = selinux_inode(inode); 3073 3074 ad.type = LSM_AUDIT_DATA_INODE; 3075 ad.u.inode = inode; 3076 3077 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3078 audited, denied, result, &ad); 3079 } 3080 3081 static int selinux_inode_permission(struct inode *inode, int mask) 3082 { 3083 const struct cred *cred = current_cred(); 3084 u32 perms; 3085 bool from_access; 3086 bool no_block = mask & MAY_NOT_BLOCK; 3087 struct inode_security_struct *isec; 3088 u32 sid; 3089 struct av_decision avd; 3090 int rc, rc2; 3091 u32 audited, denied; 3092 3093 from_access = mask & MAY_ACCESS; 3094 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3095 3096 /* No permission to check. Existence test. */ 3097 if (!mask) 3098 return 0; 3099 3100 if (unlikely(IS_PRIVATE(inode))) 3101 return 0; 3102 3103 perms = file_mask_to_av(inode->i_mode, mask); 3104 3105 sid = cred_sid(cred); 3106 isec = inode_security_rcu(inode, no_block); 3107 if (IS_ERR(isec)) 3108 return PTR_ERR(isec); 3109 3110 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, 3111 &avd); 3112 audited = avc_audit_required(perms, &avd, rc, 3113 from_access ? FILE__AUDIT_ACCESS : 0, 3114 &denied); 3115 if (likely(!audited)) 3116 return rc; 3117 3118 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3119 if (rc2) 3120 return rc2; 3121 return rc; 3122 } 3123 3124 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3125 { 3126 const struct cred *cred = current_cred(); 3127 struct inode *inode = d_backing_inode(dentry); 3128 unsigned int ia_valid = iattr->ia_valid; 3129 __u32 av = FILE__WRITE; 3130 3131 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3132 if (ia_valid & ATTR_FORCE) { 3133 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3134 ATTR_FORCE); 3135 if (!ia_valid) 3136 return 0; 3137 } 3138 3139 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3140 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3141 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3142 3143 if (selinux_policycap_openperm() && 3144 inode->i_sb->s_magic != SOCKFS_MAGIC && 3145 (ia_valid & ATTR_SIZE) && 3146 !(ia_valid & ATTR_FILE)) 3147 av |= FILE__OPEN; 3148 3149 return dentry_has_perm(cred, dentry, av); 3150 } 3151 3152 static int selinux_inode_getattr(const struct path *path) 3153 { 3154 return path_has_perm(current_cred(), path, FILE__GETATTR); 3155 } 3156 3157 static bool has_cap_mac_admin(bool audit) 3158 { 3159 const struct cred *cred = current_cred(); 3160 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3161 3162 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3163 return false; 3164 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3165 return false; 3166 return true; 3167 } 3168 3169 static int selinux_inode_setxattr(struct mnt_idmap *idmap, 3170 struct dentry *dentry, const char *name, 3171 const void *value, size_t size, int flags) 3172 { 3173 struct inode *inode = d_backing_inode(dentry); 3174 struct inode_security_struct *isec; 3175 struct superblock_security_struct *sbsec; 3176 struct common_audit_data ad; 3177 u32 newsid, sid = current_sid(); 3178 int rc = 0; 3179 3180 if (strcmp(name, XATTR_NAME_SELINUX)) { 3181 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3182 if (rc) 3183 return rc; 3184 3185 /* Not an attribute we recognize, so just check the 3186 ordinary setattr permission. */ 3187 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3188 } 3189 3190 if (!selinux_initialized()) 3191 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); 3192 3193 sbsec = selinux_superblock(inode->i_sb); 3194 if (!(sbsec->flags & SBLABEL_MNT)) 3195 return -EOPNOTSUPP; 3196 3197 if (!inode_owner_or_capable(idmap, inode)) 3198 return -EPERM; 3199 3200 ad.type = LSM_AUDIT_DATA_DENTRY; 3201 ad.u.dentry = dentry; 3202 3203 isec = backing_inode_security(dentry); 3204 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3205 FILE__RELABELFROM, &ad); 3206 if (rc) 3207 return rc; 3208 3209 rc = security_context_to_sid(value, size, &newsid, 3210 GFP_KERNEL); 3211 if (rc == -EINVAL) { 3212 if (!has_cap_mac_admin(true)) { 3213 struct audit_buffer *ab; 3214 size_t audit_size; 3215 3216 /* We strip a nul only if it is at the end, otherwise the 3217 * context contains a nul and we should audit that */ 3218 if (value) { 3219 const char *str = value; 3220 3221 if (str[size - 1] == '\0') 3222 audit_size = size - 1; 3223 else 3224 audit_size = size; 3225 } else { 3226 audit_size = 0; 3227 } 3228 ab = audit_log_start(audit_context(), 3229 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3230 if (!ab) 3231 return rc; 3232 audit_log_format(ab, "op=setxattr invalid_context="); 3233 audit_log_n_untrustedstring(ab, value, audit_size); 3234 audit_log_end(ab); 3235 3236 return rc; 3237 } 3238 rc = security_context_to_sid_force(value, 3239 size, &newsid); 3240 } 3241 if (rc) 3242 return rc; 3243 3244 rc = avc_has_perm(sid, newsid, isec->sclass, 3245 FILE__RELABELTO, &ad); 3246 if (rc) 3247 return rc; 3248 3249 rc = security_validate_transition(isec->sid, newsid, 3250 sid, isec->sclass); 3251 if (rc) 3252 return rc; 3253 3254 return avc_has_perm(newsid, 3255 sbsec->sid, 3256 SECCLASS_FILESYSTEM, 3257 FILESYSTEM__ASSOCIATE, 3258 &ad); 3259 } 3260 3261 static int selinux_inode_set_acl(struct mnt_idmap *idmap, 3262 struct dentry *dentry, const char *acl_name, 3263 struct posix_acl *kacl) 3264 { 3265 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3266 } 3267 3268 static int selinux_inode_get_acl(struct mnt_idmap *idmap, 3269 struct dentry *dentry, const char *acl_name) 3270 { 3271 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); 3272 } 3273 3274 static int selinux_inode_remove_acl(struct mnt_idmap *idmap, 3275 struct dentry *dentry, const char *acl_name) 3276 { 3277 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3278 } 3279 3280 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3281 const void *value, size_t size, 3282 int flags) 3283 { 3284 struct inode *inode = d_backing_inode(dentry); 3285 struct inode_security_struct *isec; 3286 u32 newsid; 3287 int rc; 3288 3289 if (strcmp(name, XATTR_NAME_SELINUX)) { 3290 /* Not an attribute we recognize, so nothing to do. */ 3291 return; 3292 } 3293 3294 if (!selinux_initialized()) { 3295 /* If we haven't even been initialized, then we can't validate 3296 * against a policy, so leave the label as invalid. It may 3297 * resolve to a valid label on the next revalidation try if 3298 * we've since initialized. 3299 */ 3300 return; 3301 } 3302 3303 rc = security_context_to_sid_force(value, size, 3304 &newsid); 3305 if (rc) { 3306 pr_err("SELinux: unable to map context to SID" 3307 "for (%s, %lu), rc=%d\n", 3308 inode->i_sb->s_id, inode->i_ino, -rc); 3309 return; 3310 } 3311 3312 isec = backing_inode_security(dentry); 3313 spin_lock(&isec->lock); 3314 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3315 isec->sid = newsid; 3316 isec->initialized = LABEL_INITIALIZED; 3317 spin_unlock(&isec->lock); 3318 } 3319 3320 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3321 { 3322 const struct cred *cred = current_cred(); 3323 3324 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3325 } 3326 3327 static int selinux_inode_listxattr(struct dentry *dentry) 3328 { 3329 const struct cred *cred = current_cred(); 3330 3331 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3332 } 3333 3334 static int selinux_inode_removexattr(struct mnt_idmap *idmap, 3335 struct dentry *dentry, const char *name) 3336 { 3337 if (strcmp(name, XATTR_NAME_SELINUX)) { 3338 int rc = cap_inode_removexattr(idmap, dentry, name); 3339 if (rc) 3340 return rc; 3341 3342 /* Not an attribute we recognize, so just check the 3343 ordinary setattr permission. */ 3344 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3345 } 3346 3347 if (!selinux_initialized()) 3348 return 0; 3349 3350 /* No one is allowed to remove a SELinux security label. 3351 You can change the label, but all data must be labeled. */ 3352 return -EACCES; 3353 } 3354 3355 static int selinux_path_notify(const struct path *path, u64 mask, 3356 unsigned int obj_type) 3357 { 3358 int ret; 3359 u32 perm; 3360 3361 struct common_audit_data ad; 3362 3363 ad.type = LSM_AUDIT_DATA_PATH; 3364 ad.u.path = *path; 3365 3366 /* 3367 * Set permission needed based on the type of mark being set. 3368 * Performs an additional check for sb watches. 3369 */ 3370 switch (obj_type) { 3371 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3372 perm = FILE__WATCH_MOUNT; 3373 break; 3374 case FSNOTIFY_OBJ_TYPE_SB: 3375 perm = FILE__WATCH_SB; 3376 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3377 FILESYSTEM__WATCH, &ad); 3378 if (ret) 3379 return ret; 3380 break; 3381 case FSNOTIFY_OBJ_TYPE_INODE: 3382 perm = FILE__WATCH; 3383 break; 3384 default: 3385 return -EINVAL; 3386 } 3387 3388 /* blocking watches require the file:watch_with_perm permission */ 3389 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3390 perm |= FILE__WATCH_WITH_PERM; 3391 3392 /* watches on read-like events need the file:watch_reads permission */ 3393 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3394 perm |= FILE__WATCH_READS; 3395 3396 return path_has_perm(current_cred(), path, perm); 3397 } 3398 3399 /* 3400 * Copy the inode security context value to the user. 3401 * 3402 * Permission check is handled by selinux_inode_getxattr hook. 3403 */ 3404 static int selinux_inode_getsecurity(struct mnt_idmap *idmap, 3405 struct inode *inode, const char *name, 3406 void **buffer, bool alloc) 3407 { 3408 u32 size; 3409 int error; 3410 char *context = NULL; 3411 struct inode_security_struct *isec; 3412 3413 /* 3414 * If we're not initialized yet, then we can't validate contexts, so 3415 * just let vfs_getxattr fall back to using the on-disk xattr. 3416 */ 3417 if (!selinux_initialized() || 3418 strcmp(name, XATTR_SELINUX_SUFFIX)) 3419 return -EOPNOTSUPP; 3420 3421 /* 3422 * If the caller has CAP_MAC_ADMIN, then get the raw context 3423 * value even if it is not defined by current policy; otherwise, 3424 * use the in-core value under current policy. 3425 * Use the non-auditing forms of the permission checks since 3426 * getxattr may be called by unprivileged processes commonly 3427 * and lack of permission just means that we fall back to the 3428 * in-core context value, not a denial. 3429 */ 3430 isec = inode_security(inode); 3431 if (has_cap_mac_admin(false)) 3432 error = security_sid_to_context_force(isec->sid, &context, 3433 &size); 3434 else 3435 error = security_sid_to_context(isec->sid, 3436 &context, &size); 3437 if (error) 3438 return error; 3439 error = size; 3440 if (alloc) { 3441 *buffer = context; 3442 goto out_nofree; 3443 } 3444 kfree(context); 3445 out_nofree: 3446 return error; 3447 } 3448 3449 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3450 const void *value, size_t size, int flags) 3451 { 3452 struct inode_security_struct *isec = inode_security_novalidate(inode); 3453 struct superblock_security_struct *sbsec; 3454 u32 newsid; 3455 int rc; 3456 3457 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3458 return -EOPNOTSUPP; 3459 3460 sbsec = selinux_superblock(inode->i_sb); 3461 if (!(sbsec->flags & SBLABEL_MNT)) 3462 return -EOPNOTSUPP; 3463 3464 if (!value || !size) 3465 return -EACCES; 3466 3467 rc = security_context_to_sid(value, size, &newsid, 3468 GFP_KERNEL); 3469 if (rc) 3470 return rc; 3471 3472 spin_lock(&isec->lock); 3473 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3474 isec->sid = newsid; 3475 isec->initialized = LABEL_INITIALIZED; 3476 spin_unlock(&isec->lock); 3477 return 0; 3478 } 3479 3480 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3481 { 3482 const int len = sizeof(XATTR_NAME_SELINUX); 3483 3484 if (!selinux_initialized()) 3485 return 0; 3486 3487 if (buffer && len <= buffer_size) 3488 memcpy(buffer, XATTR_NAME_SELINUX, len); 3489 return len; 3490 } 3491 3492 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3493 { 3494 struct inode_security_struct *isec = inode_security_novalidate(inode); 3495 *secid = isec->sid; 3496 } 3497 3498 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3499 { 3500 u32 sid; 3501 struct task_security_struct *tsec; 3502 struct cred *new_creds = *new; 3503 3504 if (new_creds == NULL) { 3505 new_creds = prepare_creds(); 3506 if (!new_creds) 3507 return -ENOMEM; 3508 } 3509 3510 tsec = selinux_cred(new_creds); 3511 /* Get label from overlay inode and set it in create_sid */ 3512 selinux_inode_getsecid(d_inode(src), &sid); 3513 tsec->create_sid = sid; 3514 *new = new_creds; 3515 return 0; 3516 } 3517 3518 static int selinux_inode_copy_up_xattr(const char *name) 3519 { 3520 /* The copy_up hook above sets the initial context on an inode, but we 3521 * don't then want to overwrite it by blindly copying all the lower 3522 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3523 */ 3524 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3525 return 1; /* Discard */ 3526 /* 3527 * Any other attribute apart from SELINUX is not claimed, supported 3528 * by selinux. 3529 */ 3530 return -EOPNOTSUPP; 3531 } 3532 3533 /* kernfs node operations */ 3534 3535 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3536 struct kernfs_node *kn) 3537 { 3538 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3539 u32 parent_sid, newsid, clen; 3540 int rc; 3541 char *context; 3542 3543 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3544 if (rc == -ENODATA) 3545 return 0; 3546 else if (rc < 0) 3547 return rc; 3548 3549 clen = (u32)rc; 3550 context = kmalloc(clen, GFP_KERNEL); 3551 if (!context) 3552 return -ENOMEM; 3553 3554 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3555 if (rc < 0) { 3556 kfree(context); 3557 return rc; 3558 } 3559 3560 rc = security_context_to_sid(context, clen, &parent_sid, 3561 GFP_KERNEL); 3562 kfree(context); 3563 if (rc) 3564 return rc; 3565 3566 if (tsec->create_sid) { 3567 newsid = tsec->create_sid; 3568 } else { 3569 u16 secclass = inode_mode_to_security_class(kn->mode); 3570 struct qstr q; 3571 3572 q.name = kn->name; 3573 q.hash_len = hashlen_string(kn_dir, kn->name); 3574 3575 rc = security_transition_sid(tsec->sid, 3576 parent_sid, secclass, &q, 3577 &newsid); 3578 if (rc) 3579 return rc; 3580 } 3581 3582 rc = security_sid_to_context_force(newsid, 3583 &context, &clen); 3584 if (rc) 3585 return rc; 3586 3587 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3588 XATTR_CREATE); 3589 kfree(context); 3590 return rc; 3591 } 3592 3593 3594 /* file security operations */ 3595 3596 static int selinux_revalidate_file_permission(struct file *file, int mask) 3597 { 3598 const struct cred *cred = current_cred(); 3599 struct inode *inode = file_inode(file); 3600 3601 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3602 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3603 mask |= MAY_APPEND; 3604 3605 return file_has_perm(cred, file, 3606 file_mask_to_av(inode->i_mode, mask)); 3607 } 3608 3609 static int selinux_file_permission(struct file *file, int mask) 3610 { 3611 struct inode *inode = file_inode(file); 3612 struct file_security_struct *fsec = selinux_file(file); 3613 struct inode_security_struct *isec; 3614 u32 sid = current_sid(); 3615 3616 if (!mask) 3617 /* No permission to check. Existence test. */ 3618 return 0; 3619 3620 isec = inode_security(inode); 3621 if (sid == fsec->sid && fsec->isid == isec->sid && 3622 fsec->pseqno == avc_policy_seqno()) 3623 /* No change since file_open check. */ 3624 return 0; 3625 3626 return selinux_revalidate_file_permission(file, mask); 3627 } 3628 3629 static int selinux_file_alloc_security(struct file *file) 3630 { 3631 struct file_security_struct *fsec = selinux_file(file); 3632 u32 sid = current_sid(); 3633 3634 fsec->sid = sid; 3635 fsec->fown_sid = sid; 3636 3637 return 0; 3638 } 3639 3640 /* 3641 * Check whether a task has the ioctl permission and cmd 3642 * operation to an inode. 3643 */ 3644 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3645 u32 requested, u16 cmd) 3646 { 3647 struct common_audit_data ad; 3648 struct file_security_struct *fsec = selinux_file(file); 3649 struct inode *inode = file_inode(file); 3650 struct inode_security_struct *isec; 3651 struct lsm_ioctlop_audit ioctl; 3652 u32 ssid = cred_sid(cred); 3653 int rc; 3654 u8 driver = cmd >> 8; 3655 u8 xperm = cmd & 0xff; 3656 3657 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3658 ad.u.op = &ioctl; 3659 ad.u.op->cmd = cmd; 3660 ad.u.op->path = file->f_path; 3661 3662 if (ssid != fsec->sid) { 3663 rc = avc_has_perm(ssid, fsec->sid, 3664 SECCLASS_FD, 3665 FD__USE, 3666 &ad); 3667 if (rc) 3668 goto out; 3669 } 3670 3671 if (unlikely(IS_PRIVATE(inode))) 3672 return 0; 3673 3674 isec = inode_security(inode); 3675 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3676 requested, driver, xperm, &ad); 3677 out: 3678 return rc; 3679 } 3680 3681 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3682 unsigned long arg) 3683 { 3684 const struct cred *cred = current_cred(); 3685 int error = 0; 3686 3687 switch (cmd) { 3688 case FIONREAD: 3689 case FIBMAP: 3690 case FIGETBSZ: 3691 case FS_IOC_GETFLAGS: 3692 case FS_IOC_GETVERSION: 3693 error = file_has_perm(cred, file, FILE__GETATTR); 3694 break; 3695 3696 case FS_IOC_SETFLAGS: 3697 case FS_IOC_SETVERSION: 3698 error = file_has_perm(cred, file, FILE__SETATTR); 3699 break; 3700 3701 /* sys_ioctl() checks */ 3702 case FIONBIO: 3703 case FIOASYNC: 3704 error = file_has_perm(cred, file, 0); 3705 break; 3706 3707 case KDSKBENT: 3708 case KDSKBSENT: 3709 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3710 CAP_OPT_NONE, true); 3711 break; 3712 3713 case FIOCLEX: 3714 case FIONCLEX: 3715 if (!selinux_policycap_ioctl_skip_cloexec()) 3716 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3717 break; 3718 3719 /* default case assumes that the command will go 3720 * to the file's ioctl() function. 3721 */ 3722 default: 3723 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3724 } 3725 return error; 3726 } 3727 3728 static int default_noexec __ro_after_init; 3729 3730 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3731 { 3732 const struct cred *cred = current_cred(); 3733 u32 sid = cred_sid(cred); 3734 int rc = 0; 3735 3736 if (default_noexec && 3737 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3738 (!shared && (prot & PROT_WRITE)))) { 3739 /* 3740 * We are making executable an anonymous mapping or a 3741 * private file mapping that will also be writable. 3742 * This has an additional check. 3743 */ 3744 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3745 PROCESS__EXECMEM, NULL); 3746 if (rc) 3747 goto error; 3748 } 3749 3750 if (file) { 3751 /* read access is always possible with a mapping */ 3752 u32 av = FILE__READ; 3753 3754 /* write access only matters if the mapping is shared */ 3755 if (shared && (prot & PROT_WRITE)) 3756 av |= FILE__WRITE; 3757 3758 if (prot & PROT_EXEC) 3759 av |= FILE__EXECUTE; 3760 3761 return file_has_perm(cred, file, av); 3762 } 3763 3764 error: 3765 return rc; 3766 } 3767 3768 static int selinux_mmap_addr(unsigned long addr) 3769 { 3770 int rc = 0; 3771 3772 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3773 u32 sid = current_sid(); 3774 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3775 MEMPROTECT__MMAP_ZERO, NULL); 3776 } 3777 3778 return rc; 3779 } 3780 3781 static int selinux_mmap_file(struct file *file, 3782 unsigned long reqprot __always_unused, 3783 unsigned long prot, unsigned long flags) 3784 { 3785 struct common_audit_data ad; 3786 int rc; 3787 3788 if (file) { 3789 ad.type = LSM_AUDIT_DATA_FILE; 3790 ad.u.file = file; 3791 rc = inode_has_perm(current_cred(), file_inode(file), 3792 FILE__MAP, &ad); 3793 if (rc) 3794 return rc; 3795 } 3796 3797 return file_map_prot_check(file, prot, 3798 (flags & MAP_TYPE) == MAP_SHARED); 3799 } 3800 3801 static int selinux_file_mprotect(struct vm_area_struct *vma, 3802 unsigned long reqprot __always_unused, 3803 unsigned long prot) 3804 { 3805 const struct cred *cred = current_cred(); 3806 u32 sid = cred_sid(cred); 3807 3808 if (default_noexec && 3809 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3810 int rc = 0; 3811 if (vma_is_initial_heap(vma)) { 3812 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3813 PROCESS__EXECHEAP, NULL); 3814 } else if (!vma->vm_file && (vma_is_initial_stack(vma) || 3815 vma_is_stack_for_current(vma))) { 3816 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3817 PROCESS__EXECSTACK, NULL); 3818 } else if (vma->vm_file && vma->anon_vma) { 3819 /* 3820 * We are making executable a file mapping that has 3821 * had some COW done. Since pages might have been 3822 * written, check ability to execute the possibly 3823 * modified content. This typically should only 3824 * occur for text relocations. 3825 */ 3826 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3827 } 3828 if (rc) 3829 return rc; 3830 } 3831 3832 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3833 } 3834 3835 static int selinux_file_lock(struct file *file, unsigned int cmd) 3836 { 3837 const struct cred *cred = current_cred(); 3838 3839 return file_has_perm(cred, file, FILE__LOCK); 3840 } 3841 3842 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3843 unsigned long arg) 3844 { 3845 const struct cred *cred = current_cred(); 3846 int err = 0; 3847 3848 switch (cmd) { 3849 case F_SETFL: 3850 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3851 err = file_has_perm(cred, file, FILE__WRITE); 3852 break; 3853 } 3854 fallthrough; 3855 case F_SETOWN: 3856 case F_SETSIG: 3857 case F_GETFL: 3858 case F_GETOWN: 3859 case F_GETSIG: 3860 case F_GETOWNER_UIDS: 3861 /* Just check FD__USE permission */ 3862 err = file_has_perm(cred, file, 0); 3863 break; 3864 case F_GETLK: 3865 case F_SETLK: 3866 case F_SETLKW: 3867 case F_OFD_GETLK: 3868 case F_OFD_SETLK: 3869 case F_OFD_SETLKW: 3870 #if BITS_PER_LONG == 32 3871 case F_GETLK64: 3872 case F_SETLK64: 3873 case F_SETLKW64: 3874 #endif 3875 err = file_has_perm(cred, file, FILE__LOCK); 3876 break; 3877 } 3878 3879 return err; 3880 } 3881 3882 static void selinux_file_set_fowner(struct file *file) 3883 { 3884 struct file_security_struct *fsec; 3885 3886 fsec = selinux_file(file); 3887 fsec->fown_sid = current_sid(); 3888 } 3889 3890 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3891 struct fown_struct *fown, int signum) 3892 { 3893 struct file *file; 3894 u32 sid = task_sid_obj(tsk); 3895 u32 perm; 3896 struct file_security_struct *fsec; 3897 3898 /* struct fown_struct is never outside the context of a struct file */ 3899 file = container_of(fown, struct file, f_owner); 3900 3901 fsec = selinux_file(file); 3902 3903 if (!signum) 3904 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3905 else 3906 perm = signal_to_av(signum); 3907 3908 return avc_has_perm(fsec->fown_sid, sid, 3909 SECCLASS_PROCESS, perm, NULL); 3910 } 3911 3912 static int selinux_file_receive(struct file *file) 3913 { 3914 const struct cred *cred = current_cred(); 3915 3916 return file_has_perm(cred, file, file_to_av(file)); 3917 } 3918 3919 static int selinux_file_open(struct file *file) 3920 { 3921 struct file_security_struct *fsec; 3922 struct inode_security_struct *isec; 3923 3924 fsec = selinux_file(file); 3925 isec = inode_security(file_inode(file)); 3926 /* 3927 * Save inode label and policy sequence number 3928 * at open-time so that selinux_file_permission 3929 * can determine whether revalidation is necessary. 3930 * Task label is already saved in the file security 3931 * struct as its SID. 3932 */ 3933 fsec->isid = isec->sid; 3934 fsec->pseqno = avc_policy_seqno(); 3935 /* 3936 * Since the inode label or policy seqno may have changed 3937 * between the selinux_inode_permission check and the saving 3938 * of state above, recheck that access is still permitted. 3939 * Otherwise, access might never be revalidated against the 3940 * new inode label or new policy. 3941 * This check is not redundant - do not remove. 3942 */ 3943 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3944 } 3945 3946 /* task security operations */ 3947 3948 static int selinux_task_alloc(struct task_struct *task, 3949 unsigned long clone_flags) 3950 { 3951 u32 sid = current_sid(); 3952 3953 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3954 } 3955 3956 /* 3957 * prepare a new set of credentials for modification 3958 */ 3959 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3960 gfp_t gfp) 3961 { 3962 const struct task_security_struct *old_tsec = selinux_cred(old); 3963 struct task_security_struct *tsec = selinux_cred(new); 3964 3965 *tsec = *old_tsec; 3966 return 0; 3967 } 3968 3969 /* 3970 * transfer the SELinux data to a blank set of creds 3971 */ 3972 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3973 { 3974 const struct task_security_struct *old_tsec = selinux_cred(old); 3975 struct task_security_struct *tsec = selinux_cred(new); 3976 3977 *tsec = *old_tsec; 3978 } 3979 3980 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 3981 { 3982 *secid = cred_sid(c); 3983 } 3984 3985 /* 3986 * set the security data for a kernel service 3987 * - all the creation contexts are set to unlabelled 3988 */ 3989 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3990 { 3991 struct task_security_struct *tsec = selinux_cred(new); 3992 u32 sid = current_sid(); 3993 int ret; 3994 3995 ret = avc_has_perm(sid, secid, 3996 SECCLASS_KERNEL_SERVICE, 3997 KERNEL_SERVICE__USE_AS_OVERRIDE, 3998 NULL); 3999 if (ret == 0) { 4000 tsec->sid = secid; 4001 tsec->create_sid = 0; 4002 tsec->keycreate_sid = 0; 4003 tsec->sockcreate_sid = 0; 4004 } 4005 return ret; 4006 } 4007 4008 /* 4009 * set the file creation context in a security record to the same as the 4010 * objective context of the specified inode 4011 */ 4012 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4013 { 4014 struct inode_security_struct *isec = inode_security(inode); 4015 struct task_security_struct *tsec = selinux_cred(new); 4016 u32 sid = current_sid(); 4017 int ret; 4018 4019 ret = avc_has_perm(sid, isec->sid, 4020 SECCLASS_KERNEL_SERVICE, 4021 KERNEL_SERVICE__CREATE_FILES_AS, 4022 NULL); 4023 4024 if (ret == 0) 4025 tsec->create_sid = isec->sid; 4026 return ret; 4027 } 4028 4029 static int selinux_kernel_module_request(char *kmod_name) 4030 { 4031 struct common_audit_data ad; 4032 4033 ad.type = LSM_AUDIT_DATA_KMOD; 4034 ad.u.kmod_name = kmod_name; 4035 4036 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4037 SYSTEM__MODULE_REQUEST, &ad); 4038 } 4039 4040 static int selinux_kernel_module_from_file(struct file *file) 4041 { 4042 struct common_audit_data ad; 4043 struct inode_security_struct *isec; 4044 struct file_security_struct *fsec; 4045 u32 sid = current_sid(); 4046 int rc; 4047 4048 /* init_module */ 4049 if (file == NULL) 4050 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 4051 SYSTEM__MODULE_LOAD, NULL); 4052 4053 /* finit_module */ 4054 4055 ad.type = LSM_AUDIT_DATA_FILE; 4056 ad.u.file = file; 4057 4058 fsec = selinux_file(file); 4059 if (sid != fsec->sid) { 4060 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4061 if (rc) 4062 return rc; 4063 } 4064 4065 isec = inode_security(file_inode(file)); 4066 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 4067 SYSTEM__MODULE_LOAD, &ad); 4068 } 4069 4070 static int selinux_kernel_read_file(struct file *file, 4071 enum kernel_read_file_id id, 4072 bool contents) 4073 { 4074 int rc = 0; 4075 4076 switch (id) { 4077 case READING_MODULE: 4078 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4079 break; 4080 default: 4081 break; 4082 } 4083 4084 return rc; 4085 } 4086 4087 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4088 { 4089 int rc = 0; 4090 4091 switch (id) { 4092 case LOADING_MODULE: 4093 rc = selinux_kernel_module_from_file(NULL); 4094 break; 4095 default: 4096 break; 4097 } 4098 4099 return rc; 4100 } 4101 4102 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4103 { 4104 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4105 PROCESS__SETPGID, NULL); 4106 } 4107 4108 static int selinux_task_getpgid(struct task_struct *p) 4109 { 4110 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4111 PROCESS__GETPGID, NULL); 4112 } 4113 4114 static int selinux_task_getsid(struct task_struct *p) 4115 { 4116 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4117 PROCESS__GETSESSION, NULL); 4118 } 4119 4120 static void selinux_current_getsecid_subj(u32 *secid) 4121 { 4122 *secid = current_sid(); 4123 } 4124 4125 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) 4126 { 4127 *secid = task_sid_obj(p); 4128 } 4129 4130 static int selinux_task_setnice(struct task_struct *p, int nice) 4131 { 4132 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4133 PROCESS__SETSCHED, NULL); 4134 } 4135 4136 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4137 { 4138 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4139 PROCESS__SETSCHED, NULL); 4140 } 4141 4142 static int selinux_task_getioprio(struct task_struct *p) 4143 { 4144 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4145 PROCESS__GETSCHED, NULL); 4146 } 4147 4148 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4149 unsigned int flags) 4150 { 4151 u32 av = 0; 4152 4153 if (!flags) 4154 return 0; 4155 if (flags & LSM_PRLIMIT_WRITE) 4156 av |= PROCESS__SETRLIMIT; 4157 if (flags & LSM_PRLIMIT_READ) 4158 av |= PROCESS__GETRLIMIT; 4159 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4160 SECCLASS_PROCESS, av, NULL); 4161 } 4162 4163 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4164 struct rlimit *new_rlim) 4165 { 4166 struct rlimit *old_rlim = p->signal->rlim + resource; 4167 4168 /* Control the ability to change the hard limit (whether 4169 lowering or raising it), so that the hard limit can 4170 later be used as a safe reset point for the soft limit 4171 upon context transitions. See selinux_bprm_committing_creds. */ 4172 if (old_rlim->rlim_max != new_rlim->rlim_max) 4173 return avc_has_perm(current_sid(), task_sid_obj(p), 4174 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4175 4176 return 0; 4177 } 4178 4179 static int selinux_task_setscheduler(struct task_struct *p) 4180 { 4181 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4182 PROCESS__SETSCHED, NULL); 4183 } 4184 4185 static int selinux_task_getscheduler(struct task_struct *p) 4186 { 4187 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4188 PROCESS__GETSCHED, NULL); 4189 } 4190 4191 static int selinux_task_movememory(struct task_struct *p) 4192 { 4193 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4194 PROCESS__SETSCHED, NULL); 4195 } 4196 4197 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4198 int sig, const struct cred *cred) 4199 { 4200 u32 secid; 4201 u32 perm; 4202 4203 if (!sig) 4204 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4205 else 4206 perm = signal_to_av(sig); 4207 if (!cred) 4208 secid = current_sid(); 4209 else 4210 secid = cred_sid(cred); 4211 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4212 } 4213 4214 static void selinux_task_to_inode(struct task_struct *p, 4215 struct inode *inode) 4216 { 4217 struct inode_security_struct *isec = selinux_inode(inode); 4218 u32 sid = task_sid_obj(p); 4219 4220 spin_lock(&isec->lock); 4221 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4222 isec->sid = sid; 4223 isec->initialized = LABEL_INITIALIZED; 4224 spin_unlock(&isec->lock); 4225 } 4226 4227 static int selinux_userns_create(const struct cred *cred) 4228 { 4229 u32 sid = current_sid(); 4230 4231 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4232 USER_NAMESPACE__CREATE, NULL); 4233 } 4234 4235 /* Returns error only if unable to parse addresses */ 4236 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4237 struct common_audit_data *ad, u8 *proto) 4238 { 4239 int offset, ihlen, ret = -EINVAL; 4240 struct iphdr _iph, *ih; 4241 4242 offset = skb_network_offset(skb); 4243 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4244 if (ih == NULL) 4245 goto out; 4246 4247 ihlen = ih->ihl * 4; 4248 if (ihlen < sizeof(_iph)) 4249 goto out; 4250 4251 ad->u.net->v4info.saddr = ih->saddr; 4252 ad->u.net->v4info.daddr = ih->daddr; 4253 ret = 0; 4254 4255 if (proto) 4256 *proto = ih->protocol; 4257 4258 switch (ih->protocol) { 4259 case IPPROTO_TCP: { 4260 struct tcphdr _tcph, *th; 4261 4262 if (ntohs(ih->frag_off) & IP_OFFSET) 4263 break; 4264 4265 offset += ihlen; 4266 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4267 if (th == NULL) 4268 break; 4269 4270 ad->u.net->sport = th->source; 4271 ad->u.net->dport = th->dest; 4272 break; 4273 } 4274 4275 case IPPROTO_UDP: { 4276 struct udphdr _udph, *uh; 4277 4278 if (ntohs(ih->frag_off) & IP_OFFSET) 4279 break; 4280 4281 offset += ihlen; 4282 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4283 if (uh == NULL) 4284 break; 4285 4286 ad->u.net->sport = uh->source; 4287 ad->u.net->dport = uh->dest; 4288 break; 4289 } 4290 4291 case IPPROTO_DCCP: { 4292 struct dccp_hdr _dccph, *dh; 4293 4294 if (ntohs(ih->frag_off) & IP_OFFSET) 4295 break; 4296 4297 offset += ihlen; 4298 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4299 if (dh == NULL) 4300 break; 4301 4302 ad->u.net->sport = dh->dccph_sport; 4303 ad->u.net->dport = dh->dccph_dport; 4304 break; 4305 } 4306 4307 #if IS_ENABLED(CONFIG_IP_SCTP) 4308 case IPPROTO_SCTP: { 4309 struct sctphdr _sctph, *sh; 4310 4311 if (ntohs(ih->frag_off) & IP_OFFSET) 4312 break; 4313 4314 offset += ihlen; 4315 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4316 if (sh == NULL) 4317 break; 4318 4319 ad->u.net->sport = sh->source; 4320 ad->u.net->dport = sh->dest; 4321 break; 4322 } 4323 #endif 4324 default: 4325 break; 4326 } 4327 out: 4328 return ret; 4329 } 4330 4331 #if IS_ENABLED(CONFIG_IPV6) 4332 4333 /* Returns error only if unable to parse addresses */ 4334 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4335 struct common_audit_data *ad, u8 *proto) 4336 { 4337 u8 nexthdr; 4338 int ret = -EINVAL, offset; 4339 struct ipv6hdr _ipv6h, *ip6; 4340 __be16 frag_off; 4341 4342 offset = skb_network_offset(skb); 4343 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4344 if (ip6 == NULL) 4345 goto out; 4346 4347 ad->u.net->v6info.saddr = ip6->saddr; 4348 ad->u.net->v6info.daddr = ip6->daddr; 4349 ret = 0; 4350 4351 nexthdr = ip6->nexthdr; 4352 offset += sizeof(_ipv6h); 4353 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4354 if (offset < 0) 4355 goto out; 4356 4357 if (proto) 4358 *proto = nexthdr; 4359 4360 switch (nexthdr) { 4361 case IPPROTO_TCP: { 4362 struct tcphdr _tcph, *th; 4363 4364 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4365 if (th == NULL) 4366 break; 4367 4368 ad->u.net->sport = th->source; 4369 ad->u.net->dport = th->dest; 4370 break; 4371 } 4372 4373 case IPPROTO_UDP: { 4374 struct udphdr _udph, *uh; 4375 4376 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4377 if (uh == NULL) 4378 break; 4379 4380 ad->u.net->sport = uh->source; 4381 ad->u.net->dport = uh->dest; 4382 break; 4383 } 4384 4385 case IPPROTO_DCCP: { 4386 struct dccp_hdr _dccph, *dh; 4387 4388 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4389 if (dh == NULL) 4390 break; 4391 4392 ad->u.net->sport = dh->dccph_sport; 4393 ad->u.net->dport = dh->dccph_dport; 4394 break; 4395 } 4396 4397 #if IS_ENABLED(CONFIG_IP_SCTP) 4398 case IPPROTO_SCTP: { 4399 struct sctphdr _sctph, *sh; 4400 4401 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4402 if (sh == NULL) 4403 break; 4404 4405 ad->u.net->sport = sh->source; 4406 ad->u.net->dport = sh->dest; 4407 break; 4408 } 4409 #endif 4410 /* includes fragments */ 4411 default: 4412 break; 4413 } 4414 out: 4415 return ret; 4416 } 4417 4418 #endif /* IPV6 */ 4419 4420 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4421 char **_addrp, int src, u8 *proto) 4422 { 4423 char *addrp; 4424 int ret; 4425 4426 switch (ad->u.net->family) { 4427 case PF_INET: 4428 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4429 if (ret) 4430 goto parse_error; 4431 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4432 &ad->u.net->v4info.daddr); 4433 goto okay; 4434 4435 #if IS_ENABLED(CONFIG_IPV6) 4436 case PF_INET6: 4437 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4438 if (ret) 4439 goto parse_error; 4440 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4441 &ad->u.net->v6info.daddr); 4442 goto okay; 4443 #endif /* IPV6 */ 4444 default: 4445 addrp = NULL; 4446 goto okay; 4447 } 4448 4449 parse_error: 4450 pr_warn( 4451 "SELinux: failure in selinux_parse_skb()," 4452 " unable to parse packet\n"); 4453 return ret; 4454 4455 okay: 4456 if (_addrp) 4457 *_addrp = addrp; 4458 return 0; 4459 } 4460 4461 /** 4462 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4463 * @skb: the packet 4464 * @family: protocol family 4465 * @sid: the packet's peer label SID 4466 * 4467 * Description: 4468 * Check the various different forms of network peer labeling and determine 4469 * the peer label/SID for the packet; most of the magic actually occurs in 4470 * the security server function security_net_peersid_cmp(). The function 4471 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4472 * or -EACCES if @sid is invalid due to inconsistencies with the different 4473 * peer labels. 4474 * 4475 */ 4476 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4477 { 4478 int err; 4479 u32 xfrm_sid; 4480 u32 nlbl_sid; 4481 u32 nlbl_type; 4482 4483 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4484 if (unlikely(err)) 4485 return -EACCES; 4486 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4487 if (unlikely(err)) 4488 return -EACCES; 4489 4490 err = security_net_peersid_resolve(nlbl_sid, 4491 nlbl_type, xfrm_sid, sid); 4492 if (unlikely(err)) { 4493 pr_warn( 4494 "SELinux: failure in selinux_skb_peerlbl_sid()," 4495 " unable to determine packet's peer label\n"); 4496 return -EACCES; 4497 } 4498 4499 return 0; 4500 } 4501 4502 /** 4503 * selinux_conn_sid - Determine the child socket label for a connection 4504 * @sk_sid: the parent socket's SID 4505 * @skb_sid: the packet's SID 4506 * @conn_sid: the resulting connection SID 4507 * 4508 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4509 * combined with the MLS information from @skb_sid in order to create 4510 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4511 * of @sk_sid. Returns zero on success, negative values on failure. 4512 * 4513 */ 4514 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4515 { 4516 int err = 0; 4517 4518 if (skb_sid != SECSID_NULL) 4519 err = security_sid_mls_copy(sk_sid, skb_sid, 4520 conn_sid); 4521 else 4522 *conn_sid = sk_sid; 4523 4524 return err; 4525 } 4526 4527 /* socket security operations */ 4528 4529 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4530 u16 secclass, u32 *socksid) 4531 { 4532 if (tsec->sockcreate_sid > SECSID_NULL) { 4533 *socksid = tsec->sockcreate_sid; 4534 return 0; 4535 } 4536 4537 return security_transition_sid(tsec->sid, tsec->sid, 4538 secclass, NULL, socksid); 4539 } 4540 4541 static int sock_has_perm(struct sock *sk, u32 perms) 4542 { 4543 struct sk_security_struct *sksec = sk->sk_security; 4544 struct common_audit_data ad; 4545 struct lsm_network_audit net; 4546 4547 if (sksec->sid == SECINITSID_KERNEL) 4548 return 0; 4549 4550 ad_net_init_from_sk(&ad, &net, sk); 4551 4552 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4553 &ad); 4554 } 4555 4556 static int selinux_socket_create(int family, int type, 4557 int protocol, int kern) 4558 { 4559 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4560 u32 newsid; 4561 u16 secclass; 4562 int rc; 4563 4564 if (kern) 4565 return 0; 4566 4567 secclass = socket_type_to_security_class(family, type, protocol); 4568 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4569 if (rc) 4570 return rc; 4571 4572 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4573 } 4574 4575 static int selinux_socket_post_create(struct socket *sock, int family, 4576 int type, int protocol, int kern) 4577 { 4578 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4579 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4580 struct sk_security_struct *sksec; 4581 u16 sclass = socket_type_to_security_class(family, type, protocol); 4582 u32 sid = SECINITSID_KERNEL; 4583 int err = 0; 4584 4585 if (!kern) { 4586 err = socket_sockcreate_sid(tsec, sclass, &sid); 4587 if (err) 4588 return err; 4589 } 4590 4591 isec->sclass = sclass; 4592 isec->sid = sid; 4593 isec->initialized = LABEL_INITIALIZED; 4594 4595 if (sock->sk) { 4596 sksec = sock->sk->sk_security; 4597 sksec->sclass = sclass; 4598 sksec->sid = sid; 4599 /* Allows detection of the first association on this socket */ 4600 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4601 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4602 4603 err = selinux_netlbl_socket_post_create(sock->sk, family); 4604 } 4605 4606 return err; 4607 } 4608 4609 static int selinux_socket_socketpair(struct socket *socka, 4610 struct socket *sockb) 4611 { 4612 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4613 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4614 4615 sksec_a->peer_sid = sksec_b->sid; 4616 sksec_b->peer_sid = sksec_a->sid; 4617 4618 return 0; 4619 } 4620 4621 /* Range of port numbers used to automatically bind. 4622 Need to determine whether we should perform a name_bind 4623 permission check between the socket and the port number. */ 4624 4625 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4626 { 4627 struct sock *sk = sock->sk; 4628 struct sk_security_struct *sksec = sk->sk_security; 4629 u16 family; 4630 int err; 4631 4632 err = sock_has_perm(sk, SOCKET__BIND); 4633 if (err) 4634 goto out; 4635 4636 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4637 family = sk->sk_family; 4638 if (family == PF_INET || family == PF_INET6) { 4639 char *addrp; 4640 struct common_audit_data ad; 4641 struct lsm_network_audit net = {0,}; 4642 struct sockaddr_in *addr4 = NULL; 4643 struct sockaddr_in6 *addr6 = NULL; 4644 u16 family_sa; 4645 unsigned short snum; 4646 u32 sid, node_perm; 4647 4648 /* 4649 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4650 * that validates multiple binding addresses. Because of this 4651 * need to check address->sa_family as it is possible to have 4652 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4653 */ 4654 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4655 return -EINVAL; 4656 family_sa = address->sa_family; 4657 switch (family_sa) { 4658 case AF_UNSPEC: 4659 case AF_INET: 4660 if (addrlen < sizeof(struct sockaddr_in)) 4661 return -EINVAL; 4662 addr4 = (struct sockaddr_in *)address; 4663 if (family_sa == AF_UNSPEC) { 4664 /* see __inet_bind(), we only want to allow 4665 * AF_UNSPEC if the address is INADDR_ANY 4666 */ 4667 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4668 goto err_af; 4669 family_sa = AF_INET; 4670 } 4671 snum = ntohs(addr4->sin_port); 4672 addrp = (char *)&addr4->sin_addr.s_addr; 4673 break; 4674 case AF_INET6: 4675 if (addrlen < SIN6_LEN_RFC2133) 4676 return -EINVAL; 4677 addr6 = (struct sockaddr_in6 *)address; 4678 snum = ntohs(addr6->sin6_port); 4679 addrp = (char *)&addr6->sin6_addr.s6_addr; 4680 break; 4681 default: 4682 goto err_af; 4683 } 4684 4685 ad.type = LSM_AUDIT_DATA_NET; 4686 ad.u.net = &net; 4687 ad.u.net->sport = htons(snum); 4688 ad.u.net->family = family_sa; 4689 4690 if (snum) { 4691 int low, high; 4692 4693 inet_get_local_port_range(sock_net(sk), &low, &high); 4694 4695 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4696 snum < low || snum > high) { 4697 err = sel_netport_sid(sk->sk_protocol, 4698 snum, &sid); 4699 if (err) 4700 goto out; 4701 err = avc_has_perm(sksec->sid, sid, 4702 sksec->sclass, 4703 SOCKET__NAME_BIND, &ad); 4704 if (err) 4705 goto out; 4706 } 4707 } 4708 4709 switch (sksec->sclass) { 4710 case SECCLASS_TCP_SOCKET: 4711 node_perm = TCP_SOCKET__NODE_BIND; 4712 break; 4713 4714 case SECCLASS_UDP_SOCKET: 4715 node_perm = UDP_SOCKET__NODE_BIND; 4716 break; 4717 4718 case SECCLASS_DCCP_SOCKET: 4719 node_perm = DCCP_SOCKET__NODE_BIND; 4720 break; 4721 4722 case SECCLASS_SCTP_SOCKET: 4723 node_perm = SCTP_SOCKET__NODE_BIND; 4724 break; 4725 4726 default: 4727 node_perm = RAWIP_SOCKET__NODE_BIND; 4728 break; 4729 } 4730 4731 err = sel_netnode_sid(addrp, family_sa, &sid); 4732 if (err) 4733 goto out; 4734 4735 if (family_sa == AF_INET) 4736 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4737 else 4738 ad.u.net->v6info.saddr = addr6->sin6_addr; 4739 4740 err = avc_has_perm(sksec->sid, sid, 4741 sksec->sclass, node_perm, &ad); 4742 if (err) 4743 goto out; 4744 } 4745 out: 4746 return err; 4747 err_af: 4748 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4749 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4750 return -EINVAL; 4751 return -EAFNOSUPPORT; 4752 } 4753 4754 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4755 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4756 */ 4757 static int selinux_socket_connect_helper(struct socket *sock, 4758 struct sockaddr *address, int addrlen) 4759 { 4760 struct sock *sk = sock->sk; 4761 struct sk_security_struct *sksec = sk->sk_security; 4762 int err; 4763 4764 err = sock_has_perm(sk, SOCKET__CONNECT); 4765 if (err) 4766 return err; 4767 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4768 return -EINVAL; 4769 4770 /* connect(AF_UNSPEC) has special handling, as it is a documented 4771 * way to disconnect the socket 4772 */ 4773 if (address->sa_family == AF_UNSPEC) 4774 return 0; 4775 4776 /* 4777 * If a TCP, DCCP or SCTP socket, check name_connect permission 4778 * for the port. 4779 */ 4780 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4781 sksec->sclass == SECCLASS_DCCP_SOCKET || 4782 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4783 struct common_audit_data ad; 4784 struct lsm_network_audit net = {0,}; 4785 struct sockaddr_in *addr4 = NULL; 4786 struct sockaddr_in6 *addr6 = NULL; 4787 unsigned short snum; 4788 u32 sid, perm; 4789 4790 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4791 * that validates multiple connect addresses. Because of this 4792 * need to check address->sa_family as it is possible to have 4793 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4794 */ 4795 switch (address->sa_family) { 4796 case AF_INET: 4797 addr4 = (struct sockaddr_in *)address; 4798 if (addrlen < sizeof(struct sockaddr_in)) 4799 return -EINVAL; 4800 snum = ntohs(addr4->sin_port); 4801 break; 4802 case AF_INET6: 4803 addr6 = (struct sockaddr_in6 *)address; 4804 if (addrlen < SIN6_LEN_RFC2133) 4805 return -EINVAL; 4806 snum = ntohs(addr6->sin6_port); 4807 break; 4808 default: 4809 /* Note that SCTP services expect -EINVAL, whereas 4810 * others expect -EAFNOSUPPORT. 4811 */ 4812 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4813 return -EINVAL; 4814 else 4815 return -EAFNOSUPPORT; 4816 } 4817 4818 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4819 if (err) 4820 return err; 4821 4822 switch (sksec->sclass) { 4823 case SECCLASS_TCP_SOCKET: 4824 perm = TCP_SOCKET__NAME_CONNECT; 4825 break; 4826 case SECCLASS_DCCP_SOCKET: 4827 perm = DCCP_SOCKET__NAME_CONNECT; 4828 break; 4829 case SECCLASS_SCTP_SOCKET: 4830 perm = SCTP_SOCKET__NAME_CONNECT; 4831 break; 4832 } 4833 4834 ad.type = LSM_AUDIT_DATA_NET; 4835 ad.u.net = &net; 4836 ad.u.net->dport = htons(snum); 4837 ad.u.net->family = address->sa_family; 4838 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4839 if (err) 4840 return err; 4841 } 4842 4843 return 0; 4844 } 4845 4846 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4847 static int selinux_socket_connect(struct socket *sock, 4848 struct sockaddr *address, int addrlen) 4849 { 4850 int err; 4851 struct sock *sk = sock->sk; 4852 4853 err = selinux_socket_connect_helper(sock, address, addrlen); 4854 if (err) 4855 return err; 4856 4857 return selinux_netlbl_socket_connect(sk, address); 4858 } 4859 4860 static int selinux_socket_listen(struct socket *sock, int backlog) 4861 { 4862 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4863 } 4864 4865 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4866 { 4867 int err; 4868 struct inode_security_struct *isec; 4869 struct inode_security_struct *newisec; 4870 u16 sclass; 4871 u32 sid; 4872 4873 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4874 if (err) 4875 return err; 4876 4877 isec = inode_security_novalidate(SOCK_INODE(sock)); 4878 spin_lock(&isec->lock); 4879 sclass = isec->sclass; 4880 sid = isec->sid; 4881 spin_unlock(&isec->lock); 4882 4883 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4884 newisec->sclass = sclass; 4885 newisec->sid = sid; 4886 newisec->initialized = LABEL_INITIALIZED; 4887 4888 return 0; 4889 } 4890 4891 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4892 int size) 4893 { 4894 return sock_has_perm(sock->sk, SOCKET__WRITE); 4895 } 4896 4897 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4898 int size, int flags) 4899 { 4900 return sock_has_perm(sock->sk, SOCKET__READ); 4901 } 4902 4903 static int selinux_socket_getsockname(struct socket *sock) 4904 { 4905 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4906 } 4907 4908 static int selinux_socket_getpeername(struct socket *sock) 4909 { 4910 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4911 } 4912 4913 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4914 { 4915 int err; 4916 4917 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4918 if (err) 4919 return err; 4920 4921 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4922 } 4923 4924 static int selinux_socket_getsockopt(struct socket *sock, int level, 4925 int optname) 4926 { 4927 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4928 } 4929 4930 static int selinux_socket_shutdown(struct socket *sock, int how) 4931 { 4932 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4933 } 4934 4935 static int selinux_socket_unix_stream_connect(struct sock *sock, 4936 struct sock *other, 4937 struct sock *newsk) 4938 { 4939 struct sk_security_struct *sksec_sock = sock->sk_security; 4940 struct sk_security_struct *sksec_other = other->sk_security; 4941 struct sk_security_struct *sksec_new = newsk->sk_security; 4942 struct common_audit_data ad; 4943 struct lsm_network_audit net; 4944 int err; 4945 4946 ad_net_init_from_sk(&ad, &net, other); 4947 4948 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4949 sksec_other->sclass, 4950 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4951 if (err) 4952 return err; 4953 4954 /* server child socket */ 4955 sksec_new->peer_sid = sksec_sock->sid; 4956 err = security_sid_mls_copy(sksec_other->sid, 4957 sksec_sock->sid, &sksec_new->sid); 4958 if (err) 4959 return err; 4960 4961 /* connecting socket */ 4962 sksec_sock->peer_sid = sksec_new->sid; 4963 4964 return 0; 4965 } 4966 4967 static int selinux_socket_unix_may_send(struct socket *sock, 4968 struct socket *other) 4969 { 4970 struct sk_security_struct *ssec = sock->sk->sk_security; 4971 struct sk_security_struct *osec = other->sk->sk_security; 4972 struct common_audit_data ad; 4973 struct lsm_network_audit net; 4974 4975 ad_net_init_from_sk(&ad, &net, other->sk); 4976 4977 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4978 &ad); 4979 } 4980 4981 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4982 char *addrp, u16 family, u32 peer_sid, 4983 struct common_audit_data *ad) 4984 { 4985 int err; 4986 u32 if_sid; 4987 u32 node_sid; 4988 4989 err = sel_netif_sid(ns, ifindex, &if_sid); 4990 if (err) 4991 return err; 4992 err = avc_has_perm(peer_sid, if_sid, 4993 SECCLASS_NETIF, NETIF__INGRESS, ad); 4994 if (err) 4995 return err; 4996 4997 err = sel_netnode_sid(addrp, family, &node_sid); 4998 if (err) 4999 return err; 5000 return avc_has_perm(peer_sid, node_sid, 5001 SECCLASS_NODE, NODE__RECVFROM, ad); 5002 } 5003 5004 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5005 u16 family) 5006 { 5007 int err = 0; 5008 struct sk_security_struct *sksec = sk->sk_security; 5009 u32 sk_sid = sksec->sid; 5010 struct common_audit_data ad; 5011 struct lsm_network_audit net; 5012 char *addrp; 5013 5014 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5015 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5016 if (err) 5017 return err; 5018 5019 if (selinux_secmark_enabled()) { 5020 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5021 PACKET__RECV, &ad); 5022 if (err) 5023 return err; 5024 } 5025 5026 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5027 if (err) 5028 return err; 5029 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5030 5031 return err; 5032 } 5033 5034 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5035 { 5036 int err, peerlbl_active, secmark_active; 5037 struct sk_security_struct *sksec = sk->sk_security; 5038 u16 family = sk->sk_family; 5039 u32 sk_sid = sksec->sid; 5040 struct common_audit_data ad; 5041 struct lsm_network_audit net; 5042 char *addrp; 5043 5044 if (family != PF_INET && family != PF_INET6) 5045 return 0; 5046 5047 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5048 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5049 family = PF_INET; 5050 5051 /* If any sort of compatibility mode is enabled then handoff processing 5052 * to the selinux_sock_rcv_skb_compat() function to deal with the 5053 * special handling. We do this in an attempt to keep this function 5054 * as fast and as clean as possible. */ 5055 if (!selinux_policycap_netpeer()) 5056 return selinux_sock_rcv_skb_compat(sk, skb, family); 5057 5058 secmark_active = selinux_secmark_enabled(); 5059 peerlbl_active = selinux_peerlbl_enabled(); 5060 if (!secmark_active && !peerlbl_active) 5061 return 0; 5062 5063 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5064 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5065 if (err) 5066 return err; 5067 5068 if (peerlbl_active) { 5069 u32 peer_sid; 5070 5071 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5072 if (err) 5073 return err; 5074 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5075 addrp, family, peer_sid, &ad); 5076 if (err) { 5077 selinux_netlbl_err(skb, family, err, 0); 5078 return err; 5079 } 5080 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5081 PEER__RECV, &ad); 5082 if (err) { 5083 selinux_netlbl_err(skb, family, err, 0); 5084 return err; 5085 } 5086 } 5087 5088 if (secmark_active) { 5089 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5090 PACKET__RECV, &ad); 5091 if (err) 5092 return err; 5093 } 5094 5095 return err; 5096 } 5097 5098 static int selinux_socket_getpeersec_stream(struct socket *sock, 5099 sockptr_t optval, sockptr_t optlen, 5100 unsigned int len) 5101 { 5102 int err = 0; 5103 char *scontext = NULL; 5104 u32 scontext_len; 5105 struct sk_security_struct *sksec = sock->sk->sk_security; 5106 u32 peer_sid = SECSID_NULL; 5107 5108 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5109 sksec->sclass == SECCLASS_TCP_SOCKET || 5110 sksec->sclass == SECCLASS_SCTP_SOCKET) 5111 peer_sid = sksec->peer_sid; 5112 if (peer_sid == SECSID_NULL) 5113 return -ENOPROTOOPT; 5114 5115 err = security_sid_to_context(peer_sid, &scontext, 5116 &scontext_len); 5117 if (err) 5118 return err; 5119 if (scontext_len > len) { 5120 err = -ERANGE; 5121 goto out_len; 5122 } 5123 5124 if (copy_to_sockptr(optval, scontext, scontext_len)) 5125 err = -EFAULT; 5126 out_len: 5127 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5128 err = -EFAULT; 5129 kfree(scontext); 5130 return err; 5131 } 5132 5133 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5134 { 5135 u32 peer_secid = SECSID_NULL; 5136 u16 family; 5137 struct inode_security_struct *isec; 5138 5139 if (skb && skb->protocol == htons(ETH_P_IP)) 5140 family = PF_INET; 5141 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5142 family = PF_INET6; 5143 else if (sock) 5144 family = sock->sk->sk_family; 5145 else 5146 goto out; 5147 5148 if (sock && family == PF_UNIX) { 5149 isec = inode_security_novalidate(SOCK_INODE(sock)); 5150 peer_secid = isec->sid; 5151 } else if (skb) 5152 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5153 5154 out: 5155 *secid = peer_secid; 5156 if (peer_secid == SECSID_NULL) 5157 return -EINVAL; 5158 return 0; 5159 } 5160 5161 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5162 { 5163 struct sk_security_struct *sksec; 5164 5165 sksec = kzalloc(sizeof(*sksec), priority); 5166 if (!sksec) 5167 return -ENOMEM; 5168 5169 sksec->peer_sid = SECINITSID_UNLABELED; 5170 sksec->sid = SECINITSID_UNLABELED; 5171 sksec->sclass = SECCLASS_SOCKET; 5172 selinux_netlbl_sk_security_reset(sksec); 5173 sk->sk_security = sksec; 5174 5175 return 0; 5176 } 5177 5178 static void selinux_sk_free_security(struct sock *sk) 5179 { 5180 struct sk_security_struct *sksec = sk->sk_security; 5181 5182 sk->sk_security = NULL; 5183 selinux_netlbl_sk_security_free(sksec); 5184 kfree(sksec); 5185 } 5186 5187 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5188 { 5189 struct sk_security_struct *sksec = sk->sk_security; 5190 struct sk_security_struct *newsksec = newsk->sk_security; 5191 5192 newsksec->sid = sksec->sid; 5193 newsksec->peer_sid = sksec->peer_sid; 5194 newsksec->sclass = sksec->sclass; 5195 5196 selinux_netlbl_sk_security_reset(newsksec); 5197 } 5198 5199 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5200 { 5201 if (!sk) 5202 *secid = SECINITSID_ANY_SOCKET; 5203 else { 5204 const struct sk_security_struct *sksec = sk->sk_security; 5205 5206 *secid = sksec->sid; 5207 } 5208 } 5209 5210 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5211 { 5212 struct inode_security_struct *isec = 5213 inode_security_novalidate(SOCK_INODE(parent)); 5214 struct sk_security_struct *sksec = sk->sk_security; 5215 5216 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5217 sk->sk_family == PF_UNIX) 5218 isec->sid = sksec->sid; 5219 sksec->sclass = isec->sclass; 5220 } 5221 5222 /* 5223 * Determines peer_secid for the asoc and updates socket's peer label 5224 * if it's the first association on the socket. 5225 */ 5226 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5227 struct sk_buff *skb) 5228 { 5229 struct sock *sk = asoc->base.sk; 5230 u16 family = sk->sk_family; 5231 struct sk_security_struct *sksec = sk->sk_security; 5232 struct common_audit_data ad; 5233 struct lsm_network_audit net; 5234 int err; 5235 5236 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5237 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5238 family = PF_INET; 5239 5240 if (selinux_peerlbl_enabled()) { 5241 asoc->peer_secid = SECSID_NULL; 5242 5243 /* This will return peer_sid = SECSID_NULL if there are 5244 * no peer labels, see security_net_peersid_resolve(). 5245 */ 5246 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5247 if (err) 5248 return err; 5249 5250 if (asoc->peer_secid == SECSID_NULL) 5251 asoc->peer_secid = SECINITSID_UNLABELED; 5252 } else { 5253 asoc->peer_secid = SECINITSID_UNLABELED; 5254 } 5255 5256 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5257 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5258 5259 /* Here as first association on socket. As the peer SID 5260 * was allowed by peer recv (and the netif/node checks), 5261 * then it is approved by policy and used as the primary 5262 * peer SID for getpeercon(3). 5263 */ 5264 sksec->peer_sid = asoc->peer_secid; 5265 } else if (sksec->peer_sid != asoc->peer_secid) { 5266 /* Other association peer SIDs are checked to enforce 5267 * consistency among the peer SIDs. 5268 */ 5269 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5270 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5271 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5272 &ad); 5273 if (err) 5274 return err; 5275 } 5276 return 0; 5277 } 5278 5279 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5280 * happens on an incoming connect(2), sctp_connectx(3) or 5281 * sctp_sendmsg(3) (with no association already present). 5282 */ 5283 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5284 struct sk_buff *skb) 5285 { 5286 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5287 u32 conn_sid; 5288 int err; 5289 5290 if (!selinux_policycap_extsockclass()) 5291 return 0; 5292 5293 err = selinux_sctp_process_new_assoc(asoc, skb); 5294 if (err) 5295 return err; 5296 5297 /* Compute the MLS component for the connection and store 5298 * the information in asoc. This will be used by SCTP TCP type 5299 * sockets and peeled off connections as they cause a new 5300 * socket to be generated. selinux_sctp_sk_clone() will then 5301 * plug this into the new socket. 5302 */ 5303 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5304 if (err) 5305 return err; 5306 5307 asoc->secid = conn_sid; 5308 5309 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5310 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5311 } 5312 5313 /* Called when SCTP receives a COOKIE ACK chunk as the final 5314 * response to an association request (initited by us). 5315 */ 5316 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5317 struct sk_buff *skb) 5318 { 5319 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5320 5321 if (!selinux_policycap_extsockclass()) 5322 return 0; 5323 5324 /* Inherit secid from the parent socket - this will be picked up 5325 * by selinux_sctp_sk_clone() if the association gets peeled off 5326 * into a new socket. 5327 */ 5328 asoc->secid = sksec->sid; 5329 5330 return selinux_sctp_process_new_assoc(asoc, skb); 5331 } 5332 5333 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5334 * based on their @optname. 5335 */ 5336 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5337 struct sockaddr *address, 5338 int addrlen) 5339 { 5340 int len, err = 0, walk_size = 0; 5341 void *addr_buf; 5342 struct sockaddr *addr; 5343 struct socket *sock; 5344 5345 if (!selinux_policycap_extsockclass()) 5346 return 0; 5347 5348 /* Process one or more addresses that may be IPv4 or IPv6 */ 5349 sock = sk->sk_socket; 5350 addr_buf = address; 5351 5352 while (walk_size < addrlen) { 5353 if (walk_size + sizeof(sa_family_t) > addrlen) 5354 return -EINVAL; 5355 5356 addr = addr_buf; 5357 switch (addr->sa_family) { 5358 case AF_UNSPEC: 5359 case AF_INET: 5360 len = sizeof(struct sockaddr_in); 5361 break; 5362 case AF_INET6: 5363 len = sizeof(struct sockaddr_in6); 5364 break; 5365 default: 5366 return -EINVAL; 5367 } 5368 5369 if (walk_size + len > addrlen) 5370 return -EINVAL; 5371 5372 err = -EINVAL; 5373 switch (optname) { 5374 /* Bind checks */ 5375 case SCTP_PRIMARY_ADDR: 5376 case SCTP_SET_PEER_PRIMARY_ADDR: 5377 case SCTP_SOCKOPT_BINDX_ADD: 5378 err = selinux_socket_bind(sock, addr, len); 5379 break; 5380 /* Connect checks */ 5381 case SCTP_SOCKOPT_CONNECTX: 5382 case SCTP_PARAM_SET_PRIMARY: 5383 case SCTP_PARAM_ADD_IP: 5384 case SCTP_SENDMSG_CONNECT: 5385 err = selinux_socket_connect_helper(sock, addr, len); 5386 if (err) 5387 return err; 5388 5389 /* As selinux_sctp_bind_connect() is called by the 5390 * SCTP protocol layer, the socket is already locked, 5391 * therefore selinux_netlbl_socket_connect_locked() 5392 * is called here. The situations handled are: 5393 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5394 * whenever a new IP address is added or when a new 5395 * primary address is selected. 5396 * Note that an SCTP connect(2) call happens before 5397 * the SCTP protocol layer and is handled via 5398 * selinux_socket_connect(). 5399 */ 5400 err = selinux_netlbl_socket_connect_locked(sk, addr); 5401 break; 5402 } 5403 5404 if (err) 5405 return err; 5406 5407 addr_buf += len; 5408 walk_size += len; 5409 } 5410 5411 return 0; 5412 } 5413 5414 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5415 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5416 struct sock *newsk) 5417 { 5418 struct sk_security_struct *sksec = sk->sk_security; 5419 struct sk_security_struct *newsksec = newsk->sk_security; 5420 5421 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5422 * the non-sctp clone version. 5423 */ 5424 if (!selinux_policycap_extsockclass()) 5425 return selinux_sk_clone_security(sk, newsk); 5426 5427 newsksec->sid = asoc->secid; 5428 newsksec->peer_sid = asoc->peer_secid; 5429 newsksec->sclass = sksec->sclass; 5430 selinux_netlbl_sctp_sk_clone(sk, newsk); 5431 } 5432 5433 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5434 { 5435 struct sk_security_struct *ssksec = ssk->sk_security; 5436 struct sk_security_struct *sksec = sk->sk_security; 5437 5438 ssksec->sclass = sksec->sclass; 5439 ssksec->sid = sksec->sid; 5440 5441 /* replace the existing subflow label deleting the existing one 5442 * and re-recreating a new label using the updated context 5443 */ 5444 selinux_netlbl_sk_security_free(ssksec); 5445 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5446 } 5447 5448 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5449 struct request_sock *req) 5450 { 5451 struct sk_security_struct *sksec = sk->sk_security; 5452 int err; 5453 u16 family = req->rsk_ops->family; 5454 u32 connsid; 5455 u32 peersid; 5456 5457 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5458 if (err) 5459 return err; 5460 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5461 if (err) 5462 return err; 5463 req->secid = connsid; 5464 req->peer_secid = peersid; 5465 5466 return selinux_netlbl_inet_conn_request(req, family); 5467 } 5468 5469 static void selinux_inet_csk_clone(struct sock *newsk, 5470 const struct request_sock *req) 5471 { 5472 struct sk_security_struct *newsksec = newsk->sk_security; 5473 5474 newsksec->sid = req->secid; 5475 newsksec->peer_sid = req->peer_secid; 5476 /* NOTE: Ideally, we should also get the isec->sid for the 5477 new socket in sync, but we don't have the isec available yet. 5478 So we will wait until sock_graft to do it, by which 5479 time it will have been created and available. */ 5480 5481 /* We don't need to take any sort of lock here as we are the only 5482 * thread with access to newsksec */ 5483 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5484 } 5485 5486 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5487 { 5488 u16 family = sk->sk_family; 5489 struct sk_security_struct *sksec = sk->sk_security; 5490 5491 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5492 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5493 family = PF_INET; 5494 5495 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5496 } 5497 5498 static int selinux_secmark_relabel_packet(u32 sid) 5499 { 5500 const struct task_security_struct *tsec; 5501 u32 tsid; 5502 5503 tsec = selinux_cred(current_cred()); 5504 tsid = tsec->sid; 5505 5506 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5507 NULL); 5508 } 5509 5510 static void selinux_secmark_refcount_inc(void) 5511 { 5512 atomic_inc(&selinux_secmark_refcount); 5513 } 5514 5515 static void selinux_secmark_refcount_dec(void) 5516 { 5517 atomic_dec(&selinux_secmark_refcount); 5518 } 5519 5520 static void selinux_req_classify_flow(const struct request_sock *req, 5521 struct flowi_common *flic) 5522 { 5523 flic->flowic_secid = req->secid; 5524 } 5525 5526 static int selinux_tun_dev_alloc_security(void **security) 5527 { 5528 struct tun_security_struct *tunsec; 5529 5530 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5531 if (!tunsec) 5532 return -ENOMEM; 5533 tunsec->sid = current_sid(); 5534 5535 *security = tunsec; 5536 return 0; 5537 } 5538 5539 static void selinux_tun_dev_free_security(void *security) 5540 { 5541 kfree(security); 5542 } 5543 5544 static int selinux_tun_dev_create(void) 5545 { 5546 u32 sid = current_sid(); 5547 5548 /* we aren't taking into account the "sockcreate" SID since the socket 5549 * that is being created here is not a socket in the traditional sense, 5550 * instead it is a private sock, accessible only to the kernel, and 5551 * representing a wide range of network traffic spanning multiple 5552 * connections unlike traditional sockets - check the TUN driver to 5553 * get a better understanding of why this socket is special */ 5554 5555 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5556 NULL); 5557 } 5558 5559 static int selinux_tun_dev_attach_queue(void *security) 5560 { 5561 struct tun_security_struct *tunsec = security; 5562 5563 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5564 TUN_SOCKET__ATTACH_QUEUE, NULL); 5565 } 5566 5567 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5568 { 5569 struct tun_security_struct *tunsec = security; 5570 struct sk_security_struct *sksec = sk->sk_security; 5571 5572 /* we don't currently perform any NetLabel based labeling here and it 5573 * isn't clear that we would want to do so anyway; while we could apply 5574 * labeling without the support of the TUN user the resulting labeled 5575 * traffic from the other end of the connection would almost certainly 5576 * cause confusion to the TUN user that had no idea network labeling 5577 * protocols were being used */ 5578 5579 sksec->sid = tunsec->sid; 5580 sksec->sclass = SECCLASS_TUN_SOCKET; 5581 5582 return 0; 5583 } 5584 5585 static int selinux_tun_dev_open(void *security) 5586 { 5587 struct tun_security_struct *tunsec = security; 5588 u32 sid = current_sid(); 5589 int err; 5590 5591 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5592 TUN_SOCKET__RELABELFROM, NULL); 5593 if (err) 5594 return err; 5595 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5596 TUN_SOCKET__RELABELTO, NULL); 5597 if (err) 5598 return err; 5599 tunsec->sid = sid; 5600 5601 return 0; 5602 } 5603 5604 #ifdef CONFIG_NETFILTER 5605 5606 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5607 const struct nf_hook_state *state) 5608 { 5609 int ifindex; 5610 u16 family; 5611 char *addrp; 5612 u32 peer_sid; 5613 struct common_audit_data ad; 5614 struct lsm_network_audit net; 5615 int secmark_active, peerlbl_active; 5616 5617 if (!selinux_policycap_netpeer()) 5618 return NF_ACCEPT; 5619 5620 secmark_active = selinux_secmark_enabled(); 5621 peerlbl_active = selinux_peerlbl_enabled(); 5622 if (!secmark_active && !peerlbl_active) 5623 return NF_ACCEPT; 5624 5625 family = state->pf; 5626 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5627 return NF_DROP; 5628 5629 ifindex = state->in->ifindex; 5630 ad_net_init_from_iif(&ad, &net, ifindex, family); 5631 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5632 return NF_DROP; 5633 5634 if (peerlbl_active) { 5635 int err; 5636 5637 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5638 addrp, family, peer_sid, &ad); 5639 if (err) { 5640 selinux_netlbl_err(skb, family, err, 1); 5641 return NF_DROP; 5642 } 5643 } 5644 5645 if (secmark_active) 5646 if (avc_has_perm(peer_sid, skb->secmark, 5647 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5648 return NF_DROP; 5649 5650 if (netlbl_enabled()) 5651 /* we do this in the FORWARD path and not the POST_ROUTING 5652 * path because we want to make sure we apply the necessary 5653 * labeling before IPsec is applied so we can leverage AH 5654 * protection */ 5655 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5656 return NF_DROP; 5657 5658 return NF_ACCEPT; 5659 } 5660 5661 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5662 const struct nf_hook_state *state) 5663 { 5664 struct sock *sk; 5665 u32 sid; 5666 5667 if (!netlbl_enabled()) 5668 return NF_ACCEPT; 5669 5670 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5671 * because we want to make sure we apply the necessary labeling 5672 * before IPsec is applied so we can leverage AH protection */ 5673 sk = skb->sk; 5674 if (sk) { 5675 struct sk_security_struct *sksec; 5676 5677 if (sk_listener(sk)) 5678 /* if the socket is the listening state then this 5679 * packet is a SYN-ACK packet which means it needs to 5680 * be labeled based on the connection/request_sock and 5681 * not the parent socket. unfortunately, we can't 5682 * lookup the request_sock yet as it isn't queued on 5683 * the parent socket until after the SYN-ACK is sent. 5684 * the "solution" is to simply pass the packet as-is 5685 * as any IP option based labeling should be copied 5686 * from the initial connection request (in the IP 5687 * layer). it is far from ideal, but until we get a 5688 * security label in the packet itself this is the 5689 * best we can do. */ 5690 return NF_ACCEPT; 5691 5692 /* standard practice, label using the parent socket */ 5693 sksec = sk->sk_security; 5694 sid = sksec->sid; 5695 } else 5696 sid = SECINITSID_KERNEL; 5697 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5698 return NF_DROP; 5699 5700 return NF_ACCEPT; 5701 } 5702 5703 5704 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5705 const struct nf_hook_state *state) 5706 { 5707 struct sock *sk; 5708 struct sk_security_struct *sksec; 5709 struct common_audit_data ad; 5710 struct lsm_network_audit net; 5711 u8 proto = 0; 5712 5713 sk = skb_to_full_sk(skb); 5714 if (sk == NULL) 5715 return NF_ACCEPT; 5716 sksec = sk->sk_security; 5717 5718 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5719 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5720 return NF_DROP; 5721 5722 if (selinux_secmark_enabled()) 5723 if (avc_has_perm(sksec->sid, skb->secmark, 5724 SECCLASS_PACKET, PACKET__SEND, &ad)) 5725 return NF_DROP_ERR(-ECONNREFUSED); 5726 5727 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5728 return NF_DROP_ERR(-ECONNREFUSED); 5729 5730 return NF_ACCEPT; 5731 } 5732 5733 static unsigned int selinux_ip_postroute(void *priv, 5734 struct sk_buff *skb, 5735 const struct nf_hook_state *state) 5736 { 5737 u16 family; 5738 u32 secmark_perm; 5739 u32 peer_sid; 5740 int ifindex; 5741 struct sock *sk; 5742 struct common_audit_data ad; 5743 struct lsm_network_audit net; 5744 char *addrp; 5745 int secmark_active, peerlbl_active; 5746 5747 /* If any sort of compatibility mode is enabled then handoff processing 5748 * to the selinux_ip_postroute_compat() function to deal with the 5749 * special handling. We do this in an attempt to keep this function 5750 * as fast and as clean as possible. */ 5751 if (!selinux_policycap_netpeer()) 5752 return selinux_ip_postroute_compat(skb, state); 5753 5754 secmark_active = selinux_secmark_enabled(); 5755 peerlbl_active = selinux_peerlbl_enabled(); 5756 if (!secmark_active && !peerlbl_active) 5757 return NF_ACCEPT; 5758 5759 sk = skb_to_full_sk(skb); 5760 5761 #ifdef CONFIG_XFRM 5762 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5763 * packet transformation so allow the packet to pass without any checks 5764 * since we'll have another chance to perform access control checks 5765 * when the packet is on it's final way out. 5766 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5767 * is NULL, in this case go ahead and apply access control. 5768 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5769 * TCP listening state we cannot wait until the XFRM processing 5770 * is done as we will miss out on the SA label if we do; 5771 * unfortunately, this means more work, but it is only once per 5772 * connection. */ 5773 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5774 !(sk && sk_listener(sk))) 5775 return NF_ACCEPT; 5776 #endif 5777 5778 family = state->pf; 5779 if (sk == NULL) { 5780 /* Without an associated socket the packet is either coming 5781 * from the kernel or it is being forwarded; check the packet 5782 * to determine which and if the packet is being forwarded 5783 * query the packet directly to determine the security label. */ 5784 if (skb->skb_iif) { 5785 secmark_perm = PACKET__FORWARD_OUT; 5786 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5787 return NF_DROP; 5788 } else { 5789 secmark_perm = PACKET__SEND; 5790 peer_sid = SECINITSID_KERNEL; 5791 } 5792 } else if (sk_listener(sk)) { 5793 /* Locally generated packet but the associated socket is in the 5794 * listening state which means this is a SYN-ACK packet. In 5795 * this particular case the correct security label is assigned 5796 * to the connection/request_sock but unfortunately we can't 5797 * query the request_sock as it isn't queued on the parent 5798 * socket until after the SYN-ACK packet is sent; the only 5799 * viable choice is to regenerate the label like we do in 5800 * selinux_inet_conn_request(). See also selinux_ip_output() 5801 * for similar problems. */ 5802 u32 skb_sid; 5803 struct sk_security_struct *sksec; 5804 5805 sksec = sk->sk_security; 5806 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5807 return NF_DROP; 5808 /* At this point, if the returned skb peerlbl is SECSID_NULL 5809 * and the packet has been through at least one XFRM 5810 * transformation then we must be dealing with the "final" 5811 * form of labeled IPsec packet; since we've already applied 5812 * all of our access controls on this packet we can safely 5813 * pass the packet. */ 5814 if (skb_sid == SECSID_NULL) { 5815 switch (family) { 5816 case PF_INET: 5817 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5818 return NF_ACCEPT; 5819 break; 5820 case PF_INET6: 5821 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5822 return NF_ACCEPT; 5823 break; 5824 default: 5825 return NF_DROP_ERR(-ECONNREFUSED); 5826 } 5827 } 5828 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5829 return NF_DROP; 5830 secmark_perm = PACKET__SEND; 5831 } else { 5832 /* Locally generated packet, fetch the security label from the 5833 * associated socket. */ 5834 struct sk_security_struct *sksec = sk->sk_security; 5835 peer_sid = sksec->sid; 5836 secmark_perm = PACKET__SEND; 5837 } 5838 5839 ifindex = state->out->ifindex; 5840 ad_net_init_from_iif(&ad, &net, ifindex, family); 5841 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5842 return NF_DROP; 5843 5844 if (secmark_active) 5845 if (avc_has_perm(peer_sid, skb->secmark, 5846 SECCLASS_PACKET, secmark_perm, &ad)) 5847 return NF_DROP_ERR(-ECONNREFUSED); 5848 5849 if (peerlbl_active) { 5850 u32 if_sid; 5851 u32 node_sid; 5852 5853 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5854 return NF_DROP; 5855 if (avc_has_perm(peer_sid, if_sid, 5856 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5857 return NF_DROP_ERR(-ECONNREFUSED); 5858 5859 if (sel_netnode_sid(addrp, family, &node_sid)) 5860 return NF_DROP; 5861 if (avc_has_perm(peer_sid, node_sid, 5862 SECCLASS_NODE, NODE__SENDTO, &ad)) 5863 return NF_DROP_ERR(-ECONNREFUSED); 5864 } 5865 5866 return NF_ACCEPT; 5867 } 5868 #endif /* CONFIG_NETFILTER */ 5869 5870 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5871 { 5872 int rc = 0; 5873 unsigned int msg_len; 5874 unsigned int data_len = skb->len; 5875 unsigned char *data = skb->data; 5876 struct nlmsghdr *nlh; 5877 struct sk_security_struct *sksec = sk->sk_security; 5878 u16 sclass = sksec->sclass; 5879 u32 perm; 5880 5881 while (data_len >= nlmsg_total_size(0)) { 5882 nlh = (struct nlmsghdr *)data; 5883 5884 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5885 * users which means we can't reject skb's with bogus 5886 * length fields; our solution is to follow what 5887 * netlink_rcv_skb() does and simply skip processing at 5888 * messages with length fields that are clearly junk 5889 */ 5890 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5891 return 0; 5892 5893 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5894 if (rc == 0) { 5895 rc = sock_has_perm(sk, perm); 5896 if (rc) 5897 return rc; 5898 } else if (rc == -EINVAL) { 5899 /* -EINVAL is a missing msg/perm mapping */ 5900 pr_warn_ratelimited("SELinux: unrecognized netlink" 5901 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5902 " pid=%d comm=%s\n", 5903 sk->sk_protocol, nlh->nlmsg_type, 5904 secclass_map[sclass - 1].name, 5905 task_pid_nr(current), current->comm); 5906 if (enforcing_enabled() && 5907 !security_get_allow_unknown()) 5908 return rc; 5909 rc = 0; 5910 } else if (rc == -ENOENT) { 5911 /* -ENOENT is a missing socket/class mapping, ignore */ 5912 rc = 0; 5913 } else { 5914 return rc; 5915 } 5916 5917 /* move to the next message after applying netlink padding */ 5918 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5919 if (msg_len >= data_len) 5920 return 0; 5921 data_len -= msg_len; 5922 data += msg_len; 5923 } 5924 5925 return rc; 5926 } 5927 5928 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5929 { 5930 isec->sclass = sclass; 5931 isec->sid = current_sid(); 5932 } 5933 5934 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5935 u32 perms) 5936 { 5937 struct ipc_security_struct *isec; 5938 struct common_audit_data ad; 5939 u32 sid = current_sid(); 5940 5941 isec = selinux_ipc(ipc_perms); 5942 5943 ad.type = LSM_AUDIT_DATA_IPC; 5944 ad.u.ipc_id = ipc_perms->key; 5945 5946 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 5947 } 5948 5949 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5950 { 5951 struct msg_security_struct *msec; 5952 5953 msec = selinux_msg_msg(msg); 5954 msec->sid = SECINITSID_UNLABELED; 5955 5956 return 0; 5957 } 5958 5959 /* message queue security operations */ 5960 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5961 { 5962 struct ipc_security_struct *isec; 5963 struct common_audit_data ad; 5964 u32 sid = current_sid(); 5965 5966 isec = selinux_ipc(msq); 5967 ipc_init_security(isec, SECCLASS_MSGQ); 5968 5969 ad.type = LSM_AUDIT_DATA_IPC; 5970 ad.u.ipc_id = msq->key; 5971 5972 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5973 MSGQ__CREATE, &ad); 5974 } 5975 5976 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 5977 { 5978 struct ipc_security_struct *isec; 5979 struct common_audit_data ad; 5980 u32 sid = current_sid(); 5981 5982 isec = selinux_ipc(msq); 5983 5984 ad.type = LSM_AUDIT_DATA_IPC; 5985 ad.u.ipc_id = msq->key; 5986 5987 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5988 MSGQ__ASSOCIATE, &ad); 5989 } 5990 5991 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 5992 { 5993 u32 perms; 5994 5995 switch (cmd) { 5996 case IPC_INFO: 5997 case MSG_INFO: 5998 /* No specific object, just general system-wide information. */ 5999 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6000 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6001 case IPC_STAT: 6002 case MSG_STAT: 6003 case MSG_STAT_ANY: 6004 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6005 break; 6006 case IPC_SET: 6007 perms = MSGQ__SETATTR; 6008 break; 6009 case IPC_RMID: 6010 perms = MSGQ__DESTROY; 6011 break; 6012 default: 6013 return 0; 6014 } 6015 6016 return ipc_has_perm(msq, perms); 6017 } 6018 6019 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6020 { 6021 struct ipc_security_struct *isec; 6022 struct msg_security_struct *msec; 6023 struct common_audit_data ad; 6024 u32 sid = current_sid(); 6025 int rc; 6026 6027 isec = selinux_ipc(msq); 6028 msec = selinux_msg_msg(msg); 6029 6030 /* 6031 * First time through, need to assign label to the message 6032 */ 6033 if (msec->sid == SECINITSID_UNLABELED) { 6034 /* 6035 * Compute new sid based on current process and 6036 * message queue this message will be stored in 6037 */ 6038 rc = security_transition_sid(sid, isec->sid, 6039 SECCLASS_MSG, NULL, &msec->sid); 6040 if (rc) 6041 return rc; 6042 } 6043 6044 ad.type = LSM_AUDIT_DATA_IPC; 6045 ad.u.ipc_id = msq->key; 6046 6047 /* Can this process write to the queue? */ 6048 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6049 MSGQ__WRITE, &ad); 6050 if (!rc) 6051 /* Can this process send the message */ 6052 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6053 MSG__SEND, &ad); 6054 if (!rc) 6055 /* Can the message be put in the queue? */ 6056 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6057 MSGQ__ENQUEUE, &ad); 6058 6059 return rc; 6060 } 6061 6062 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6063 struct task_struct *target, 6064 long type, int mode) 6065 { 6066 struct ipc_security_struct *isec; 6067 struct msg_security_struct *msec; 6068 struct common_audit_data ad; 6069 u32 sid = task_sid_obj(target); 6070 int rc; 6071 6072 isec = selinux_ipc(msq); 6073 msec = selinux_msg_msg(msg); 6074 6075 ad.type = LSM_AUDIT_DATA_IPC; 6076 ad.u.ipc_id = msq->key; 6077 6078 rc = avc_has_perm(sid, isec->sid, 6079 SECCLASS_MSGQ, MSGQ__READ, &ad); 6080 if (!rc) 6081 rc = avc_has_perm(sid, msec->sid, 6082 SECCLASS_MSG, MSG__RECEIVE, &ad); 6083 return rc; 6084 } 6085 6086 /* Shared Memory security operations */ 6087 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6088 { 6089 struct ipc_security_struct *isec; 6090 struct common_audit_data ad; 6091 u32 sid = current_sid(); 6092 6093 isec = selinux_ipc(shp); 6094 ipc_init_security(isec, SECCLASS_SHM); 6095 6096 ad.type = LSM_AUDIT_DATA_IPC; 6097 ad.u.ipc_id = shp->key; 6098 6099 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6100 SHM__CREATE, &ad); 6101 } 6102 6103 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6104 { 6105 struct ipc_security_struct *isec; 6106 struct common_audit_data ad; 6107 u32 sid = current_sid(); 6108 6109 isec = selinux_ipc(shp); 6110 6111 ad.type = LSM_AUDIT_DATA_IPC; 6112 ad.u.ipc_id = shp->key; 6113 6114 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6115 SHM__ASSOCIATE, &ad); 6116 } 6117 6118 /* Note, at this point, shp is locked down */ 6119 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6120 { 6121 u32 perms; 6122 6123 switch (cmd) { 6124 case IPC_INFO: 6125 case SHM_INFO: 6126 /* No specific object, just general system-wide information. */ 6127 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6128 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6129 case IPC_STAT: 6130 case SHM_STAT: 6131 case SHM_STAT_ANY: 6132 perms = SHM__GETATTR | SHM__ASSOCIATE; 6133 break; 6134 case IPC_SET: 6135 perms = SHM__SETATTR; 6136 break; 6137 case SHM_LOCK: 6138 case SHM_UNLOCK: 6139 perms = SHM__LOCK; 6140 break; 6141 case IPC_RMID: 6142 perms = SHM__DESTROY; 6143 break; 6144 default: 6145 return 0; 6146 } 6147 6148 return ipc_has_perm(shp, perms); 6149 } 6150 6151 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6152 char __user *shmaddr, int shmflg) 6153 { 6154 u32 perms; 6155 6156 if (shmflg & SHM_RDONLY) 6157 perms = SHM__READ; 6158 else 6159 perms = SHM__READ | SHM__WRITE; 6160 6161 return ipc_has_perm(shp, perms); 6162 } 6163 6164 /* Semaphore security operations */ 6165 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6166 { 6167 struct ipc_security_struct *isec; 6168 struct common_audit_data ad; 6169 u32 sid = current_sid(); 6170 6171 isec = selinux_ipc(sma); 6172 ipc_init_security(isec, SECCLASS_SEM); 6173 6174 ad.type = LSM_AUDIT_DATA_IPC; 6175 ad.u.ipc_id = sma->key; 6176 6177 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6178 SEM__CREATE, &ad); 6179 } 6180 6181 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6182 { 6183 struct ipc_security_struct *isec; 6184 struct common_audit_data ad; 6185 u32 sid = current_sid(); 6186 6187 isec = selinux_ipc(sma); 6188 6189 ad.type = LSM_AUDIT_DATA_IPC; 6190 ad.u.ipc_id = sma->key; 6191 6192 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6193 SEM__ASSOCIATE, &ad); 6194 } 6195 6196 /* Note, at this point, sma is locked down */ 6197 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6198 { 6199 int err; 6200 u32 perms; 6201 6202 switch (cmd) { 6203 case IPC_INFO: 6204 case SEM_INFO: 6205 /* No specific object, just general system-wide information. */ 6206 return avc_has_perm(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 const 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(current_sid(), __tsec->sid, 6294 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6295 if (error) 6296 goto bad; 6297 } 6298 6299 if (!strcmp(name, "current")) 6300 sid = __tsec->sid; 6301 else if (!strcmp(name, "prev")) 6302 sid = __tsec->osid; 6303 else if (!strcmp(name, "exec")) 6304 sid = __tsec->exec_sid; 6305 else if (!strcmp(name, "fscreate")) 6306 sid = __tsec->create_sid; 6307 else if (!strcmp(name, "keycreate")) 6308 sid = __tsec->keycreate_sid; 6309 else if (!strcmp(name, "sockcreate")) 6310 sid = __tsec->sockcreate_sid; 6311 else { 6312 error = -EINVAL; 6313 goto bad; 6314 } 6315 rcu_read_unlock(); 6316 6317 if (!sid) 6318 return 0; 6319 6320 error = security_sid_to_context(sid, value, &len); 6321 if (error) 6322 return error; 6323 return len; 6324 6325 bad: 6326 rcu_read_unlock(); 6327 return error; 6328 } 6329 6330 static int selinux_setprocattr(const char *name, void *value, size_t size) 6331 { 6332 struct task_security_struct *tsec; 6333 struct cred *new; 6334 u32 mysid = current_sid(), sid = 0, ptsid; 6335 int error; 6336 char *str = value; 6337 6338 /* 6339 * Basic control over ability to set these attributes at all. 6340 */ 6341 if (!strcmp(name, "exec")) 6342 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6343 PROCESS__SETEXEC, NULL); 6344 else if (!strcmp(name, "fscreate")) 6345 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6346 PROCESS__SETFSCREATE, NULL); 6347 else if (!strcmp(name, "keycreate")) 6348 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6349 PROCESS__SETKEYCREATE, NULL); 6350 else if (!strcmp(name, "sockcreate")) 6351 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6352 PROCESS__SETSOCKCREATE, NULL); 6353 else if (!strcmp(name, "current")) 6354 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6355 PROCESS__SETCURRENT, NULL); 6356 else 6357 error = -EINVAL; 6358 if (error) 6359 return error; 6360 6361 /* Obtain a SID for the context, if one was specified. */ 6362 if (size && str[0] && str[0] != '\n') { 6363 if (str[size-1] == '\n') { 6364 str[size-1] = 0; 6365 size--; 6366 } 6367 error = security_context_to_sid(value, size, 6368 &sid, GFP_KERNEL); 6369 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6370 if (!has_cap_mac_admin(true)) { 6371 struct audit_buffer *ab; 6372 size_t audit_size; 6373 6374 /* We strip a nul only if it is at the end, otherwise the 6375 * context contains a nul and we should audit that */ 6376 if (str[size - 1] == '\0') 6377 audit_size = size - 1; 6378 else 6379 audit_size = size; 6380 ab = audit_log_start(audit_context(), 6381 GFP_ATOMIC, 6382 AUDIT_SELINUX_ERR); 6383 if (!ab) 6384 return error; 6385 audit_log_format(ab, "op=fscreate invalid_context="); 6386 audit_log_n_untrustedstring(ab, value, audit_size); 6387 audit_log_end(ab); 6388 6389 return error; 6390 } 6391 error = security_context_to_sid_force(value, size, 6392 &sid); 6393 } 6394 if (error) 6395 return error; 6396 } 6397 6398 new = prepare_creds(); 6399 if (!new) 6400 return -ENOMEM; 6401 6402 /* Permission checking based on the specified context is 6403 performed during the actual operation (execve, 6404 open/mkdir/...), when we know the full context of the 6405 operation. See selinux_bprm_creds_for_exec for the execve 6406 checks and may_create for the file creation checks. The 6407 operation will then fail if the context is not permitted. */ 6408 tsec = selinux_cred(new); 6409 if (!strcmp(name, "exec")) { 6410 tsec->exec_sid = sid; 6411 } else if (!strcmp(name, "fscreate")) { 6412 tsec->create_sid = sid; 6413 } else if (!strcmp(name, "keycreate")) { 6414 if (sid) { 6415 error = avc_has_perm(mysid, sid, 6416 SECCLASS_KEY, KEY__CREATE, NULL); 6417 if (error) 6418 goto abort_change; 6419 } 6420 tsec->keycreate_sid = sid; 6421 } else if (!strcmp(name, "sockcreate")) { 6422 tsec->sockcreate_sid = sid; 6423 } else if (!strcmp(name, "current")) { 6424 error = -EINVAL; 6425 if (sid == 0) 6426 goto abort_change; 6427 6428 /* Only allow single threaded processes to change context */ 6429 if (!current_is_single_threaded()) { 6430 error = security_bounded_transition(tsec->sid, sid); 6431 if (error) 6432 goto abort_change; 6433 } 6434 6435 /* Check permissions for the transition. */ 6436 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6437 PROCESS__DYNTRANSITION, NULL); 6438 if (error) 6439 goto abort_change; 6440 6441 /* Check for ptracing, and update the task SID if ok. 6442 Otherwise, leave SID unchanged and fail. */ 6443 ptsid = ptrace_parent_sid(); 6444 if (ptsid != 0) { 6445 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6446 PROCESS__PTRACE, NULL); 6447 if (error) 6448 goto abort_change; 6449 } 6450 6451 tsec->sid = sid; 6452 } else { 6453 error = -EINVAL; 6454 goto abort_change; 6455 } 6456 6457 commit_creds(new); 6458 return size; 6459 6460 abort_change: 6461 abort_creds(new); 6462 return error; 6463 } 6464 6465 static int selinux_ismaclabel(const char *name) 6466 { 6467 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6468 } 6469 6470 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6471 { 6472 return security_sid_to_context(secid, 6473 secdata, seclen); 6474 } 6475 6476 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6477 { 6478 return security_context_to_sid(secdata, seclen, 6479 secid, GFP_KERNEL); 6480 } 6481 6482 static void selinux_release_secctx(char *secdata, u32 seclen) 6483 { 6484 kfree(secdata); 6485 } 6486 6487 static void selinux_inode_invalidate_secctx(struct inode *inode) 6488 { 6489 struct inode_security_struct *isec = selinux_inode(inode); 6490 6491 spin_lock(&isec->lock); 6492 isec->initialized = LABEL_INVALID; 6493 spin_unlock(&isec->lock); 6494 } 6495 6496 /* 6497 * called with inode->i_mutex locked 6498 */ 6499 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6500 { 6501 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6502 ctx, ctxlen, 0); 6503 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6504 return rc == -EOPNOTSUPP ? 0 : rc; 6505 } 6506 6507 /* 6508 * called with inode->i_mutex locked 6509 */ 6510 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6511 { 6512 return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6513 ctx, ctxlen, 0); 6514 } 6515 6516 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6517 { 6518 int len = 0; 6519 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6520 XATTR_SELINUX_SUFFIX, ctx, true); 6521 if (len < 0) 6522 return len; 6523 *ctxlen = len; 6524 return 0; 6525 } 6526 #ifdef CONFIG_KEYS 6527 6528 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6529 unsigned long flags) 6530 { 6531 const struct task_security_struct *tsec; 6532 struct key_security_struct *ksec; 6533 6534 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6535 if (!ksec) 6536 return -ENOMEM; 6537 6538 tsec = selinux_cred(cred); 6539 if (tsec->keycreate_sid) 6540 ksec->sid = tsec->keycreate_sid; 6541 else 6542 ksec->sid = tsec->sid; 6543 6544 k->security = ksec; 6545 return 0; 6546 } 6547 6548 static void selinux_key_free(struct key *k) 6549 { 6550 struct key_security_struct *ksec = k->security; 6551 6552 k->security = NULL; 6553 kfree(ksec); 6554 } 6555 6556 static int selinux_key_permission(key_ref_t key_ref, 6557 const struct cred *cred, 6558 enum key_need_perm need_perm) 6559 { 6560 struct key *key; 6561 struct key_security_struct *ksec; 6562 u32 perm, sid; 6563 6564 switch (need_perm) { 6565 case KEY_NEED_VIEW: 6566 perm = KEY__VIEW; 6567 break; 6568 case KEY_NEED_READ: 6569 perm = KEY__READ; 6570 break; 6571 case KEY_NEED_WRITE: 6572 perm = KEY__WRITE; 6573 break; 6574 case KEY_NEED_SEARCH: 6575 perm = KEY__SEARCH; 6576 break; 6577 case KEY_NEED_LINK: 6578 perm = KEY__LINK; 6579 break; 6580 case KEY_NEED_SETATTR: 6581 perm = KEY__SETATTR; 6582 break; 6583 case KEY_NEED_UNLINK: 6584 case KEY_SYSADMIN_OVERRIDE: 6585 case KEY_AUTHTOKEN_OVERRIDE: 6586 case KEY_DEFER_PERM_CHECK: 6587 return 0; 6588 default: 6589 WARN_ON(1); 6590 return -EPERM; 6591 6592 } 6593 6594 sid = cred_sid(cred); 6595 key = key_ref_to_ptr(key_ref); 6596 ksec = key->security; 6597 6598 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6599 } 6600 6601 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6602 { 6603 struct key_security_struct *ksec = key->security; 6604 char *context = NULL; 6605 unsigned len; 6606 int rc; 6607 6608 rc = security_sid_to_context(ksec->sid, 6609 &context, &len); 6610 if (!rc) 6611 rc = len; 6612 *_buffer = context; 6613 return rc; 6614 } 6615 6616 #ifdef CONFIG_KEY_NOTIFICATIONS 6617 static int selinux_watch_key(struct key *key) 6618 { 6619 struct key_security_struct *ksec = key->security; 6620 u32 sid = current_sid(); 6621 6622 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6623 } 6624 #endif 6625 #endif 6626 6627 #ifdef CONFIG_SECURITY_INFINIBAND 6628 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6629 { 6630 struct common_audit_data ad; 6631 int err; 6632 u32 sid = 0; 6633 struct ib_security_struct *sec = ib_sec; 6634 struct lsm_ibpkey_audit ibpkey; 6635 6636 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6637 if (err) 6638 return err; 6639 6640 ad.type = LSM_AUDIT_DATA_IBPKEY; 6641 ibpkey.subnet_prefix = subnet_prefix; 6642 ibpkey.pkey = pkey_val; 6643 ad.u.ibpkey = &ibpkey; 6644 return avc_has_perm(sec->sid, sid, 6645 SECCLASS_INFINIBAND_PKEY, 6646 INFINIBAND_PKEY__ACCESS, &ad); 6647 } 6648 6649 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6650 u8 port_num) 6651 { 6652 struct common_audit_data ad; 6653 int err; 6654 u32 sid = 0; 6655 struct ib_security_struct *sec = ib_sec; 6656 struct lsm_ibendport_audit ibendport; 6657 6658 err = security_ib_endport_sid(dev_name, port_num, 6659 &sid); 6660 6661 if (err) 6662 return err; 6663 6664 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6665 ibendport.dev_name = dev_name; 6666 ibendport.port = port_num; 6667 ad.u.ibendport = &ibendport; 6668 return avc_has_perm(sec->sid, sid, 6669 SECCLASS_INFINIBAND_ENDPORT, 6670 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6671 } 6672 6673 static int selinux_ib_alloc_security(void **ib_sec) 6674 { 6675 struct ib_security_struct *sec; 6676 6677 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6678 if (!sec) 6679 return -ENOMEM; 6680 sec->sid = current_sid(); 6681 6682 *ib_sec = sec; 6683 return 0; 6684 } 6685 6686 static void selinux_ib_free_security(void *ib_sec) 6687 { 6688 kfree(ib_sec); 6689 } 6690 #endif 6691 6692 #ifdef CONFIG_BPF_SYSCALL 6693 static int selinux_bpf(int cmd, union bpf_attr *attr, 6694 unsigned int size) 6695 { 6696 u32 sid = current_sid(); 6697 int ret; 6698 6699 switch (cmd) { 6700 case BPF_MAP_CREATE: 6701 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6702 NULL); 6703 break; 6704 case BPF_PROG_LOAD: 6705 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6706 NULL); 6707 break; 6708 default: 6709 ret = 0; 6710 break; 6711 } 6712 6713 return ret; 6714 } 6715 6716 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6717 { 6718 u32 av = 0; 6719 6720 if (fmode & FMODE_READ) 6721 av |= BPF__MAP_READ; 6722 if (fmode & FMODE_WRITE) 6723 av |= BPF__MAP_WRITE; 6724 return av; 6725 } 6726 6727 /* This function will check the file pass through unix socket or binder to see 6728 * if it is a bpf related object. And apply corresponding checks on the bpf 6729 * object based on the type. The bpf maps and programs, not like other files and 6730 * socket, are using a shared anonymous inode inside the kernel as their inode. 6731 * So checking that inode cannot identify if the process have privilege to 6732 * access the bpf object and that's why we have to add this additional check in 6733 * selinux_file_receive and selinux_binder_transfer_files. 6734 */ 6735 static int bpf_fd_pass(const struct file *file, u32 sid) 6736 { 6737 struct bpf_security_struct *bpfsec; 6738 struct bpf_prog *prog; 6739 struct bpf_map *map; 6740 int ret; 6741 6742 if (file->f_op == &bpf_map_fops) { 6743 map = file->private_data; 6744 bpfsec = map->security; 6745 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6746 bpf_map_fmode_to_av(file->f_mode), NULL); 6747 if (ret) 6748 return ret; 6749 } else if (file->f_op == &bpf_prog_fops) { 6750 prog = file->private_data; 6751 bpfsec = prog->aux->security; 6752 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6753 BPF__PROG_RUN, NULL); 6754 if (ret) 6755 return ret; 6756 } 6757 return 0; 6758 } 6759 6760 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6761 { 6762 u32 sid = current_sid(); 6763 struct bpf_security_struct *bpfsec; 6764 6765 bpfsec = map->security; 6766 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6767 bpf_map_fmode_to_av(fmode), NULL); 6768 } 6769 6770 static int selinux_bpf_prog(struct bpf_prog *prog) 6771 { 6772 u32 sid = current_sid(); 6773 struct bpf_security_struct *bpfsec; 6774 6775 bpfsec = prog->aux->security; 6776 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6777 BPF__PROG_RUN, NULL); 6778 } 6779 6780 static int selinux_bpf_map_alloc(struct bpf_map *map) 6781 { 6782 struct bpf_security_struct *bpfsec; 6783 6784 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6785 if (!bpfsec) 6786 return -ENOMEM; 6787 6788 bpfsec->sid = current_sid(); 6789 map->security = bpfsec; 6790 6791 return 0; 6792 } 6793 6794 static void selinux_bpf_map_free(struct bpf_map *map) 6795 { 6796 struct bpf_security_struct *bpfsec = map->security; 6797 6798 map->security = NULL; 6799 kfree(bpfsec); 6800 } 6801 6802 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6803 { 6804 struct bpf_security_struct *bpfsec; 6805 6806 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6807 if (!bpfsec) 6808 return -ENOMEM; 6809 6810 bpfsec->sid = current_sid(); 6811 aux->security = bpfsec; 6812 6813 return 0; 6814 } 6815 6816 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6817 { 6818 struct bpf_security_struct *bpfsec = aux->security; 6819 6820 aux->security = NULL; 6821 kfree(bpfsec); 6822 } 6823 #endif 6824 6825 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 6826 .lbs_cred = sizeof(struct task_security_struct), 6827 .lbs_file = sizeof(struct file_security_struct), 6828 .lbs_inode = sizeof(struct inode_security_struct), 6829 .lbs_ipc = sizeof(struct ipc_security_struct), 6830 .lbs_msg_msg = sizeof(struct msg_security_struct), 6831 .lbs_superblock = sizeof(struct superblock_security_struct), 6832 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 6833 }; 6834 6835 #ifdef CONFIG_PERF_EVENTS 6836 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6837 { 6838 u32 requested, sid = current_sid(); 6839 6840 if (type == PERF_SECURITY_OPEN) 6841 requested = PERF_EVENT__OPEN; 6842 else if (type == PERF_SECURITY_CPU) 6843 requested = PERF_EVENT__CPU; 6844 else if (type == PERF_SECURITY_KERNEL) 6845 requested = PERF_EVENT__KERNEL; 6846 else if (type == PERF_SECURITY_TRACEPOINT) 6847 requested = PERF_EVENT__TRACEPOINT; 6848 else 6849 return -EINVAL; 6850 6851 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 6852 requested, NULL); 6853 } 6854 6855 static int selinux_perf_event_alloc(struct perf_event *event) 6856 { 6857 struct perf_event_security_struct *perfsec; 6858 6859 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6860 if (!perfsec) 6861 return -ENOMEM; 6862 6863 perfsec->sid = current_sid(); 6864 event->security = perfsec; 6865 6866 return 0; 6867 } 6868 6869 static void selinux_perf_event_free(struct perf_event *event) 6870 { 6871 struct perf_event_security_struct *perfsec = event->security; 6872 6873 event->security = NULL; 6874 kfree(perfsec); 6875 } 6876 6877 static int selinux_perf_event_read(struct perf_event *event) 6878 { 6879 struct perf_event_security_struct *perfsec = event->security; 6880 u32 sid = current_sid(); 6881 6882 return avc_has_perm(sid, perfsec->sid, 6883 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6884 } 6885 6886 static int selinux_perf_event_write(struct perf_event *event) 6887 { 6888 struct perf_event_security_struct *perfsec = event->security; 6889 u32 sid = current_sid(); 6890 6891 return avc_has_perm(sid, perfsec->sid, 6892 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6893 } 6894 #endif 6895 6896 #ifdef CONFIG_IO_URING 6897 /** 6898 * selinux_uring_override_creds - check the requested cred override 6899 * @new: the target creds 6900 * 6901 * Check to see if the current task is allowed to override it's credentials 6902 * to service an io_uring operation. 6903 */ 6904 static int selinux_uring_override_creds(const struct cred *new) 6905 { 6906 return avc_has_perm(current_sid(), cred_sid(new), 6907 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 6908 } 6909 6910 /** 6911 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 6912 * 6913 * Check to see if the current task is allowed to create a new io_uring 6914 * kernel polling thread. 6915 */ 6916 static int selinux_uring_sqpoll(void) 6917 { 6918 u32 sid = current_sid(); 6919 6920 return avc_has_perm(sid, sid, 6921 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 6922 } 6923 6924 /** 6925 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 6926 * @ioucmd: the io_uring command structure 6927 * 6928 * Check to see if the current domain is allowed to execute an 6929 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 6930 * 6931 */ 6932 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 6933 { 6934 struct file *file = ioucmd->file; 6935 struct inode *inode = file_inode(file); 6936 struct inode_security_struct *isec = selinux_inode(inode); 6937 struct common_audit_data ad; 6938 6939 ad.type = LSM_AUDIT_DATA_FILE; 6940 ad.u.file = file; 6941 6942 return avc_has_perm(current_sid(), isec->sid, 6943 SECCLASS_IO_URING, IO_URING__CMD, &ad); 6944 } 6945 #endif /* CONFIG_IO_URING */ 6946 6947 /* 6948 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6949 * 1. any hooks that don't belong to (2.) or (3.) below, 6950 * 2. hooks that both access structures allocated by other hooks, and allocate 6951 * structures that can be later accessed by other hooks (mostly "cloning" 6952 * hooks), 6953 * 3. hooks that only allocate structures that can be later accessed by other 6954 * hooks ("allocating" hooks). 6955 * 6956 * Please follow block comment delimiters in the list to keep this order. 6957 */ 6958 static struct security_hook_list selinux_hooks[] __ro_after_init = { 6959 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6960 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6961 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6962 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6963 6964 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6965 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6966 LSM_HOOK_INIT(capget, selinux_capget), 6967 LSM_HOOK_INIT(capset, selinux_capset), 6968 LSM_HOOK_INIT(capable, selinux_capable), 6969 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6970 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6971 LSM_HOOK_INIT(syslog, selinux_syslog), 6972 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6973 6974 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6975 6976 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 6977 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6978 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6979 6980 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 6981 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 6982 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6983 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6984 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6985 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6986 LSM_HOOK_INIT(sb_mount, selinux_mount), 6987 LSM_HOOK_INIT(sb_umount, selinux_umount), 6988 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6989 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6990 6991 LSM_HOOK_INIT(move_mount, selinux_move_mount), 6992 6993 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6994 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 6995 6996 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 6997 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 6998 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 6999 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7000 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7001 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7002 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7003 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7004 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7005 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7006 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7007 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7008 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7009 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7010 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7011 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7012 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7013 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7014 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7015 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7016 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7017 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7018 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7019 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7020 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7021 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7022 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7023 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7024 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7025 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7026 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7027 7028 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7029 7030 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7031 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7032 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7033 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7034 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7035 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7036 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7037 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7038 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7039 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7040 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7041 7042 LSM_HOOK_INIT(file_open, selinux_file_open), 7043 7044 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7045 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7046 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7047 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7048 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7049 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7050 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7051 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7052 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7053 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7054 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7055 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7056 LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), 7057 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), 7058 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7059 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7060 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7061 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7062 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7063 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7064 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7065 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7066 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7067 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7068 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7069 7070 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7071 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7072 7073 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7074 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7075 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7076 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7077 7078 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7079 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7080 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7081 7082 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7083 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7084 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7085 7086 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7087 7088 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7089 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7090 7091 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7092 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7093 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7094 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7095 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7096 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7097 7098 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7099 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7100 7101 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7102 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7103 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7104 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7105 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7106 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7107 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7108 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7109 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7110 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7111 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7112 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7113 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7114 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7115 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7116 LSM_HOOK_INIT(socket_getpeersec_stream, 7117 selinux_socket_getpeersec_stream), 7118 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7119 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7120 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7121 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7122 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7123 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7124 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7125 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7126 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7127 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7128 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7129 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7130 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7131 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7132 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7133 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7134 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7135 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7136 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7137 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7138 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7139 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7140 #ifdef CONFIG_SECURITY_INFINIBAND 7141 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7142 LSM_HOOK_INIT(ib_endport_manage_subnet, 7143 selinux_ib_endport_manage_subnet), 7144 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7145 #endif 7146 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7147 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7148 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7149 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7150 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7151 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7152 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7153 selinux_xfrm_state_pol_flow_match), 7154 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7155 #endif 7156 7157 #ifdef CONFIG_KEYS 7158 LSM_HOOK_INIT(key_free, selinux_key_free), 7159 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7160 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7161 #ifdef CONFIG_KEY_NOTIFICATIONS 7162 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7163 #endif 7164 #endif 7165 7166 #ifdef CONFIG_AUDIT 7167 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7168 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7169 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7170 #endif 7171 7172 #ifdef CONFIG_BPF_SYSCALL 7173 LSM_HOOK_INIT(bpf, selinux_bpf), 7174 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7175 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7176 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7177 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7178 #endif 7179 7180 #ifdef CONFIG_PERF_EVENTS 7181 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7182 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7183 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7184 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7185 #endif 7186 7187 #ifdef CONFIG_IO_URING 7188 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7189 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7190 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7191 #endif 7192 7193 /* 7194 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7195 */ 7196 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7197 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7198 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7199 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7200 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7201 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7202 #endif 7203 7204 /* 7205 * PUT "ALLOCATING" HOOKS HERE 7206 */ 7207 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7208 LSM_HOOK_INIT(msg_queue_alloc_security, 7209 selinux_msg_queue_alloc_security), 7210 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7211 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7212 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7213 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7214 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7215 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7216 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7217 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7218 #ifdef CONFIG_SECURITY_INFINIBAND 7219 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7220 #endif 7221 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7222 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7223 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7224 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7225 selinux_xfrm_state_alloc_acquire), 7226 #endif 7227 #ifdef CONFIG_KEYS 7228 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7229 #endif 7230 #ifdef CONFIG_AUDIT 7231 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7232 #endif 7233 #ifdef CONFIG_BPF_SYSCALL 7234 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7235 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7236 #endif 7237 #ifdef CONFIG_PERF_EVENTS 7238 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7239 #endif 7240 }; 7241 7242 static __init int selinux_init(void) 7243 { 7244 pr_info("SELinux: Initializing.\n"); 7245 7246 memset(&selinux_state, 0, sizeof(selinux_state)); 7247 enforcing_set(selinux_enforcing_boot); 7248 selinux_avc_init(); 7249 mutex_init(&selinux_state.status_lock); 7250 mutex_init(&selinux_state.policy_mutex); 7251 7252 /* Set the security state for the initial task. */ 7253 cred_init_security(); 7254 7255 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7256 if (!default_noexec) 7257 pr_notice("SELinux: virtual memory is executable by default\n"); 7258 7259 avc_init(); 7260 7261 avtab_cache_init(); 7262 7263 ebitmap_cache_init(); 7264 7265 hashtab_cache_init(); 7266 7267 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7268 7269 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7270 panic("SELinux: Unable to register AVC netcache callback\n"); 7271 7272 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7273 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7274 7275 if (selinux_enforcing_boot) 7276 pr_debug("SELinux: Starting in enforcing mode\n"); 7277 else 7278 pr_debug("SELinux: Starting in permissive mode\n"); 7279 7280 fs_validate_description("selinux", selinux_fs_parameters); 7281 7282 return 0; 7283 } 7284 7285 static void delayed_superblock_init(struct super_block *sb, void *unused) 7286 { 7287 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7288 } 7289 7290 void selinux_complete_init(void) 7291 { 7292 pr_debug("SELinux: Completing initialization.\n"); 7293 7294 /* Set up any superblocks initialized prior to the policy load. */ 7295 pr_debug("SELinux: Setting up existing superblocks.\n"); 7296 iterate_supers(delayed_superblock_init, NULL); 7297 } 7298 7299 /* SELinux requires early initialization in order to label 7300 all processes and objects when they are created. */ 7301 DEFINE_LSM(selinux) = { 7302 .name = "selinux", 7303 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7304 .enabled = &selinux_enabled_boot, 7305 .blobs = &selinux_blob_sizes, 7306 .init = selinux_init, 7307 }; 7308 7309 #if defined(CONFIG_NETFILTER) 7310 static const struct nf_hook_ops selinux_nf_ops[] = { 7311 { 7312 .hook = selinux_ip_postroute, 7313 .pf = NFPROTO_IPV4, 7314 .hooknum = NF_INET_POST_ROUTING, 7315 .priority = NF_IP_PRI_SELINUX_LAST, 7316 }, 7317 { 7318 .hook = selinux_ip_forward, 7319 .pf = NFPROTO_IPV4, 7320 .hooknum = NF_INET_FORWARD, 7321 .priority = NF_IP_PRI_SELINUX_FIRST, 7322 }, 7323 { 7324 .hook = selinux_ip_output, 7325 .pf = NFPROTO_IPV4, 7326 .hooknum = NF_INET_LOCAL_OUT, 7327 .priority = NF_IP_PRI_SELINUX_FIRST, 7328 }, 7329 #if IS_ENABLED(CONFIG_IPV6) 7330 { 7331 .hook = selinux_ip_postroute, 7332 .pf = NFPROTO_IPV6, 7333 .hooknum = NF_INET_POST_ROUTING, 7334 .priority = NF_IP6_PRI_SELINUX_LAST, 7335 }, 7336 { 7337 .hook = selinux_ip_forward, 7338 .pf = NFPROTO_IPV6, 7339 .hooknum = NF_INET_FORWARD, 7340 .priority = NF_IP6_PRI_SELINUX_FIRST, 7341 }, 7342 { 7343 .hook = selinux_ip_output, 7344 .pf = NFPROTO_IPV6, 7345 .hooknum = NF_INET_LOCAL_OUT, 7346 .priority = NF_IP6_PRI_SELINUX_FIRST, 7347 }, 7348 #endif /* IPV6 */ 7349 }; 7350 7351 static int __net_init selinux_nf_register(struct net *net) 7352 { 7353 return nf_register_net_hooks(net, selinux_nf_ops, 7354 ARRAY_SIZE(selinux_nf_ops)); 7355 } 7356 7357 static void __net_exit selinux_nf_unregister(struct net *net) 7358 { 7359 nf_unregister_net_hooks(net, selinux_nf_ops, 7360 ARRAY_SIZE(selinux_nf_ops)); 7361 } 7362 7363 static struct pernet_operations selinux_net_ops = { 7364 .init = selinux_nf_register, 7365 .exit = selinux_nf_unregister, 7366 }; 7367 7368 static int __init selinux_nf_ip_init(void) 7369 { 7370 int err; 7371 7372 if (!selinux_enabled_boot) 7373 return 0; 7374 7375 pr_debug("SELinux: Registering netfilter hooks\n"); 7376 7377 err = register_pernet_subsys(&selinux_net_ops); 7378 if (err) 7379 panic("SELinux: register_pernet_subsys: error %d\n", err); 7380 7381 return 0; 7382 } 7383 __initcall(selinux_nf_ip_init); 7384 #endif /* CONFIG_NETFILTER */ 7385