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 <uapi/linux/shm.h> 89 #include <linux/bpf.h> 90 #include <linux/kernfs.h> 91 #include <linux/stringhash.h> /* for hashlen_string() */ 92 #include <uapi/linux/mount.h> 93 #include <linux/fsnotify.h> 94 #include <linux/fanotify.h> 95 #include <linux/io_uring/cmd.h> 96 #include <uapi/linux/lsm.h> 97 98 #include "avc.h" 99 #include "objsec.h" 100 #include "netif.h" 101 #include "netnode.h" 102 #include "netport.h" 103 #include "ibpkey.h" 104 #include "xfrm.h" 105 #include "netlabel.h" 106 #include "audit.h" 107 #include "avc_ss.h" 108 109 #define SELINUX_INODE_INIT_XATTRS 1 110 111 struct selinux_state selinux_state; 112 113 /* SECMARK reference count */ 114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 115 116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 117 static int selinux_enforcing_boot __initdata; 118 119 static int __init enforcing_setup(char *str) 120 { 121 unsigned long enforcing; 122 if (!kstrtoul(str, 0, &enforcing)) 123 selinux_enforcing_boot = enforcing ? 1 : 0; 124 return 1; 125 } 126 __setup("enforcing=", enforcing_setup); 127 #else 128 #define selinux_enforcing_boot 1 129 #endif 130 131 int selinux_enabled_boot __initdata = 1; 132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 133 static int __init selinux_enabled_setup(char *str) 134 { 135 unsigned long enabled; 136 if (!kstrtoul(str, 0, &enabled)) 137 selinux_enabled_boot = enabled ? 1 : 0; 138 return 1; 139 } 140 __setup("selinux=", selinux_enabled_setup); 141 #endif 142 143 static int __init checkreqprot_setup(char *str) 144 { 145 unsigned long checkreqprot; 146 147 if (!kstrtoul(str, 0, &checkreqprot)) { 148 if (checkreqprot) 149 pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n"); 150 } 151 return 1; 152 } 153 __setup("checkreqprot=", checkreqprot_setup); 154 155 /** 156 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 157 * 158 * Description: 159 * This function checks the SECMARK reference counter to see if any SECMARK 160 * targets are currently configured, if the reference counter is greater than 161 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 162 * enabled, false (0) if SECMARK is disabled. If the always_check_network 163 * policy capability is enabled, SECMARK is always considered enabled. 164 * 165 */ 166 static int selinux_secmark_enabled(void) 167 { 168 return (selinux_policycap_alwaysnetwork() || 169 atomic_read(&selinux_secmark_refcount)); 170 } 171 172 /** 173 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 174 * 175 * Description: 176 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 177 * (1) if any are enabled or false (0) if neither are enabled. If the 178 * always_check_network policy capability is enabled, peer labeling 179 * is always considered enabled. 180 * 181 */ 182 static int selinux_peerlbl_enabled(void) 183 { 184 return (selinux_policycap_alwaysnetwork() || 185 netlbl_enabled() || selinux_xfrm_enabled()); 186 } 187 188 static int selinux_netcache_avc_callback(u32 event) 189 { 190 if (event == AVC_CALLBACK_RESET) { 191 sel_netif_flush(); 192 sel_netnode_flush(); 193 sel_netport_flush(); 194 synchronize_net(); 195 } 196 return 0; 197 } 198 199 static int selinux_lsm_notifier_avc_callback(u32 event) 200 { 201 if (event == AVC_CALLBACK_RESET) { 202 sel_ib_pkey_flush(); 203 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 204 } 205 206 return 0; 207 } 208 209 /* 210 * initialise the security for the init task 211 */ 212 static void cred_init_security(void) 213 { 214 struct task_security_struct *tsec; 215 216 tsec = selinux_cred(unrcu_pointer(current->real_cred)); 217 tsec->osid = tsec->sid = SECINITSID_KERNEL; 218 } 219 220 /* 221 * get the security ID of a set of credentials 222 */ 223 static inline u32 cred_sid(const struct cred *cred) 224 { 225 const struct task_security_struct *tsec; 226 227 tsec = selinux_cred(cred); 228 return tsec->sid; 229 } 230 231 static void __ad_net_init(struct common_audit_data *ad, 232 struct lsm_network_audit *net, 233 int ifindex, struct sock *sk, u16 family) 234 { 235 ad->type = LSM_AUDIT_DATA_NET; 236 ad->u.net = net; 237 net->netif = ifindex; 238 net->sk = sk; 239 net->family = family; 240 } 241 242 static void ad_net_init_from_sk(struct common_audit_data *ad, 243 struct lsm_network_audit *net, 244 struct sock *sk) 245 { 246 __ad_net_init(ad, net, 0, sk, 0); 247 } 248 249 static void ad_net_init_from_iif(struct common_audit_data *ad, 250 struct lsm_network_audit *net, 251 int ifindex, u16 family) 252 { 253 __ad_net_init(ad, net, ifindex, NULL, family); 254 } 255 256 /* 257 * get the objective security ID of a task 258 */ 259 static inline u32 task_sid_obj(const struct task_struct *task) 260 { 261 u32 sid; 262 263 rcu_read_lock(); 264 sid = cred_sid(__task_cred(task)); 265 rcu_read_unlock(); 266 return sid; 267 } 268 269 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 270 271 /* 272 * Try reloading inode security labels that have been marked as invalid. The 273 * @may_sleep parameter indicates when sleeping and thus reloading labels is 274 * allowed; when set to false, returns -ECHILD when the label is 275 * invalid. The @dentry parameter should be set to a dentry of the inode. 276 */ 277 static int __inode_security_revalidate(struct inode *inode, 278 struct dentry *dentry, 279 bool may_sleep) 280 { 281 struct inode_security_struct *isec = selinux_inode(inode); 282 283 might_sleep_if(may_sleep); 284 285 /* 286 * The check of isec->initialized below is racy but 287 * inode_doinit_with_dentry() will recheck with 288 * isec->lock held. 289 */ 290 if (selinux_initialized() && 291 data_race(isec->initialized != LABEL_INITIALIZED)) { 292 if (!may_sleep) 293 return -ECHILD; 294 295 /* 296 * Try reloading the inode security label. This will fail if 297 * @opt_dentry is NULL and no dentry for this inode can be 298 * found; in that case, continue using the old label. 299 */ 300 inode_doinit_with_dentry(inode, dentry); 301 } 302 return 0; 303 } 304 305 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 306 { 307 return selinux_inode(inode); 308 } 309 310 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 311 { 312 int error; 313 314 error = __inode_security_revalidate(inode, NULL, !rcu); 315 if (error) 316 return ERR_PTR(error); 317 return selinux_inode(inode); 318 } 319 320 /* 321 * Get the security label of an inode. 322 */ 323 static struct inode_security_struct *inode_security(struct inode *inode) 324 { 325 __inode_security_revalidate(inode, NULL, true); 326 return selinux_inode(inode); 327 } 328 329 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 330 { 331 struct inode *inode = d_backing_inode(dentry); 332 333 return selinux_inode(inode); 334 } 335 336 /* 337 * Get the security label of a dentry's backing inode. 338 */ 339 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 340 { 341 struct inode *inode = d_backing_inode(dentry); 342 343 __inode_security_revalidate(inode, dentry, true); 344 return selinux_inode(inode); 345 } 346 347 static void inode_free_security(struct inode *inode) 348 { 349 struct inode_security_struct *isec = selinux_inode(inode); 350 struct superblock_security_struct *sbsec; 351 352 if (!isec) 353 return; 354 sbsec = selinux_superblock(inode->i_sb); 355 /* 356 * As not all inode security structures are in a list, we check for 357 * empty list outside of the lock to make sure that we won't waste 358 * time taking a lock doing nothing. 359 * 360 * The list_del_init() function can be safely called more than once. 361 * It should not be possible for this function to be called with 362 * concurrent list_add(), but for better safety against future changes 363 * in the code, we use list_empty_careful() here. 364 */ 365 if (!list_empty_careful(&isec->list)) { 366 spin_lock(&sbsec->isec_lock); 367 list_del_init(&isec->list); 368 spin_unlock(&sbsec->isec_lock); 369 } 370 } 371 372 struct selinux_mnt_opts { 373 u32 fscontext_sid; 374 u32 context_sid; 375 u32 rootcontext_sid; 376 u32 defcontext_sid; 377 }; 378 379 static void selinux_free_mnt_opts(void *mnt_opts) 380 { 381 kfree(mnt_opts); 382 } 383 384 enum { 385 Opt_error = -1, 386 Opt_context = 0, 387 Opt_defcontext = 1, 388 Opt_fscontext = 2, 389 Opt_rootcontext = 3, 390 Opt_seclabel = 4, 391 }; 392 393 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 394 static const struct { 395 const char *name; 396 int len; 397 int opt; 398 bool has_arg; 399 } tokens[] = { 400 A(context, true), 401 A(fscontext, true), 402 A(defcontext, true), 403 A(rootcontext, true), 404 A(seclabel, false), 405 }; 406 #undef A 407 408 static int match_opt_prefix(char *s, int l, char **arg) 409 { 410 unsigned int i; 411 412 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 413 size_t len = tokens[i].len; 414 if (len > l || memcmp(s, tokens[i].name, len)) 415 continue; 416 if (tokens[i].has_arg) { 417 if (len == l || s[len] != '=') 418 continue; 419 *arg = s + len + 1; 420 } else if (len != l) 421 continue; 422 return tokens[i].opt; 423 } 424 return Opt_error; 425 } 426 427 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 428 429 static int may_context_mount_sb_relabel(u32 sid, 430 struct superblock_security_struct *sbsec, 431 const struct cred *cred) 432 { 433 const struct task_security_struct *tsec = selinux_cred(cred); 434 int rc; 435 436 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 437 FILESYSTEM__RELABELFROM, NULL); 438 if (rc) 439 return rc; 440 441 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 442 FILESYSTEM__RELABELTO, NULL); 443 return rc; 444 } 445 446 static int may_context_mount_inode_relabel(u32 sid, 447 struct superblock_security_struct *sbsec, 448 const struct cred *cred) 449 { 450 const struct task_security_struct *tsec = selinux_cred(cred); 451 int rc; 452 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 453 FILESYSTEM__RELABELFROM, NULL); 454 if (rc) 455 return rc; 456 457 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 458 FILESYSTEM__ASSOCIATE, NULL); 459 return rc; 460 } 461 462 static int selinux_is_genfs_special_handling(struct super_block *sb) 463 { 464 /* Special handling. Genfs but also in-core setxattr handler */ 465 return !strcmp(sb->s_type->name, "sysfs") || 466 !strcmp(sb->s_type->name, "pstore") || 467 !strcmp(sb->s_type->name, "debugfs") || 468 !strcmp(sb->s_type->name, "tracefs") || 469 !strcmp(sb->s_type->name, "rootfs") || 470 (selinux_policycap_cgroupseclabel() && 471 (!strcmp(sb->s_type->name, "cgroup") || 472 !strcmp(sb->s_type->name, "cgroup2"))); 473 } 474 475 static int selinux_is_sblabel_mnt(struct super_block *sb) 476 { 477 struct superblock_security_struct *sbsec = selinux_superblock(sb); 478 479 /* 480 * IMPORTANT: Double-check logic in this function when adding a new 481 * SECURITY_FS_USE_* definition! 482 */ 483 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 484 485 switch (sbsec->behavior) { 486 case SECURITY_FS_USE_XATTR: 487 case SECURITY_FS_USE_TRANS: 488 case SECURITY_FS_USE_TASK: 489 case SECURITY_FS_USE_NATIVE: 490 return 1; 491 492 case SECURITY_FS_USE_GENFS: 493 return selinux_is_genfs_special_handling(sb); 494 495 /* Never allow relabeling on context mounts */ 496 case SECURITY_FS_USE_MNTPOINT: 497 case SECURITY_FS_USE_NONE: 498 default: 499 return 0; 500 } 501 } 502 503 static int sb_check_xattr_support(struct super_block *sb) 504 { 505 struct superblock_security_struct *sbsec = selinux_superblock(sb); 506 struct dentry *root = sb->s_root; 507 struct inode *root_inode = d_backing_inode(root); 508 u32 sid; 509 int rc; 510 511 /* 512 * Make sure that the xattr handler exists and that no 513 * error other than -ENODATA is returned by getxattr on 514 * the root directory. -ENODATA is ok, as this may be 515 * the first boot of the SELinux kernel before we have 516 * assigned xattr values to the filesystem. 517 */ 518 if (!(root_inode->i_opflags & IOP_XATTR)) { 519 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", 520 sb->s_id, sb->s_type->name); 521 goto fallback; 522 } 523 524 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 525 if (rc < 0 && rc != -ENODATA) { 526 if (rc == -EOPNOTSUPP) { 527 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", 528 sb->s_id, sb->s_type->name); 529 goto fallback; 530 } else { 531 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", 532 sb->s_id, sb->s_type->name, -rc); 533 return rc; 534 } 535 } 536 return 0; 537 538 fallback: 539 /* No xattr support - try to fallback to genfs if possible. */ 540 rc = security_genfs_sid(sb->s_type->name, "/", 541 SECCLASS_DIR, &sid); 542 if (rc) 543 return -EOPNOTSUPP; 544 545 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", 546 sb->s_id, sb->s_type->name); 547 sbsec->behavior = SECURITY_FS_USE_GENFS; 548 sbsec->sid = sid; 549 return 0; 550 } 551 552 static int sb_finish_set_opts(struct super_block *sb) 553 { 554 struct superblock_security_struct *sbsec = selinux_superblock(sb); 555 struct dentry *root = sb->s_root; 556 struct inode *root_inode = d_backing_inode(root); 557 int rc = 0; 558 559 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 560 rc = sb_check_xattr_support(sb); 561 if (rc) 562 return rc; 563 } 564 565 sbsec->flags |= SE_SBINITIALIZED; 566 567 /* 568 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 569 * leave the flag untouched because sb_clone_mnt_opts might be handing 570 * us a superblock that needs the flag to be cleared. 571 */ 572 if (selinux_is_sblabel_mnt(sb)) 573 sbsec->flags |= SBLABEL_MNT; 574 else 575 sbsec->flags &= ~SBLABEL_MNT; 576 577 /* Initialize the root inode. */ 578 rc = inode_doinit_with_dentry(root_inode, root); 579 580 /* Initialize any other inodes associated with the superblock, e.g. 581 inodes created prior to initial policy load or inodes created 582 during get_sb by a pseudo filesystem that directly 583 populates itself. */ 584 spin_lock(&sbsec->isec_lock); 585 while (!list_empty(&sbsec->isec_head)) { 586 struct inode_security_struct *isec = 587 list_first_entry(&sbsec->isec_head, 588 struct inode_security_struct, list); 589 struct inode *inode = isec->inode; 590 list_del_init(&isec->list); 591 spin_unlock(&sbsec->isec_lock); 592 inode = igrab(inode); 593 if (inode) { 594 if (!IS_PRIVATE(inode)) 595 inode_doinit_with_dentry(inode, NULL); 596 iput(inode); 597 } 598 spin_lock(&sbsec->isec_lock); 599 } 600 spin_unlock(&sbsec->isec_lock); 601 return rc; 602 } 603 604 static int bad_option(struct superblock_security_struct *sbsec, char flag, 605 u32 old_sid, u32 new_sid) 606 { 607 char mnt_flags = sbsec->flags & SE_MNTMASK; 608 609 /* check if the old mount command had the same options */ 610 if (sbsec->flags & SE_SBINITIALIZED) 611 if (!(sbsec->flags & flag) || 612 (old_sid != new_sid)) 613 return 1; 614 615 /* check if we were passed the same options twice, 616 * aka someone passed context=a,context=b 617 */ 618 if (!(sbsec->flags & SE_SBINITIALIZED)) 619 if (mnt_flags & flag) 620 return 1; 621 return 0; 622 } 623 624 /* 625 * Allow filesystems with binary mount data to explicitly set mount point 626 * labeling information. 627 */ 628 static int selinux_set_mnt_opts(struct super_block *sb, 629 void *mnt_opts, 630 unsigned long kern_flags, 631 unsigned long *set_kern_flags) 632 { 633 const struct cred *cred = current_cred(); 634 struct superblock_security_struct *sbsec = selinux_superblock(sb); 635 struct dentry *root = sb->s_root; 636 struct selinux_mnt_opts *opts = mnt_opts; 637 struct inode_security_struct *root_isec; 638 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 639 u32 defcontext_sid = 0; 640 int rc = 0; 641 642 /* 643 * Specifying internal flags without providing a place to 644 * place the results is not allowed 645 */ 646 if (kern_flags && !set_kern_flags) 647 return -EINVAL; 648 649 mutex_lock(&sbsec->lock); 650 651 if (!selinux_initialized()) { 652 if (!opts) { 653 /* Defer initialization until selinux_complete_init, 654 after the initial policy is loaded and the security 655 server is ready to handle calls. */ 656 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 657 sbsec->flags |= SE_SBNATIVE; 658 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 659 } 660 goto out; 661 } 662 rc = -EINVAL; 663 pr_warn("SELinux: Unable to set superblock options " 664 "before the security server is initialized\n"); 665 goto out; 666 } 667 668 /* 669 * Binary mount data FS will come through this function twice. Once 670 * from an explicit call and once from the generic calls from the vfs. 671 * Since the generic VFS calls will not contain any security mount data 672 * we need to skip the double mount verification. 673 * 674 * This does open a hole in which we will not notice if the first 675 * mount using this sb set explicit options and a second mount using 676 * this sb does not set any security options. (The first options 677 * will be used for both mounts) 678 */ 679 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 680 && !opts) 681 goto out; 682 683 root_isec = backing_inode_security_novalidate(root); 684 685 /* 686 * parse the mount options, check if they are valid sids. 687 * also check if someone is trying to mount the same sb more 688 * than once with different security options. 689 */ 690 if (opts) { 691 if (opts->fscontext_sid) { 692 fscontext_sid = opts->fscontext_sid; 693 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 694 fscontext_sid)) 695 goto out_double_mount; 696 sbsec->flags |= FSCONTEXT_MNT; 697 } 698 if (opts->context_sid) { 699 context_sid = opts->context_sid; 700 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 701 context_sid)) 702 goto out_double_mount; 703 sbsec->flags |= CONTEXT_MNT; 704 } 705 if (opts->rootcontext_sid) { 706 rootcontext_sid = opts->rootcontext_sid; 707 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 708 rootcontext_sid)) 709 goto out_double_mount; 710 sbsec->flags |= ROOTCONTEXT_MNT; 711 } 712 if (opts->defcontext_sid) { 713 defcontext_sid = opts->defcontext_sid; 714 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 715 defcontext_sid)) 716 goto out_double_mount; 717 sbsec->flags |= DEFCONTEXT_MNT; 718 } 719 } 720 721 if (sbsec->flags & SE_SBINITIALIZED) { 722 /* previously mounted with options, but not on this attempt? */ 723 if ((sbsec->flags & SE_MNTMASK) && !opts) 724 goto out_double_mount; 725 rc = 0; 726 goto out; 727 } 728 729 if (strcmp(sb->s_type->name, "proc") == 0) 730 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 731 732 if (!strcmp(sb->s_type->name, "debugfs") || 733 !strcmp(sb->s_type->name, "tracefs") || 734 !strcmp(sb->s_type->name, "binder") || 735 !strcmp(sb->s_type->name, "bpf") || 736 !strcmp(sb->s_type->name, "pstore") || 737 !strcmp(sb->s_type->name, "securityfs")) 738 sbsec->flags |= SE_SBGENFS; 739 740 if (!strcmp(sb->s_type->name, "sysfs") || 741 !strcmp(sb->s_type->name, "cgroup") || 742 !strcmp(sb->s_type->name, "cgroup2")) 743 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 744 745 if (!sbsec->behavior) { 746 /* 747 * Determine the labeling behavior to use for this 748 * filesystem type. 749 */ 750 rc = security_fs_use(sb); 751 if (rc) { 752 pr_warn("%s: security_fs_use(%s) returned %d\n", 753 __func__, sb->s_type->name, rc); 754 goto out; 755 } 756 } 757 758 /* 759 * If this is a user namespace mount and the filesystem type is not 760 * explicitly whitelisted, then no contexts are allowed on the command 761 * line and security labels must be ignored. 762 */ 763 if (sb->s_user_ns != &init_user_ns && 764 strcmp(sb->s_type->name, "tmpfs") && 765 strcmp(sb->s_type->name, "ramfs") && 766 strcmp(sb->s_type->name, "devpts") && 767 strcmp(sb->s_type->name, "overlay")) { 768 if (context_sid || fscontext_sid || rootcontext_sid || 769 defcontext_sid) { 770 rc = -EACCES; 771 goto out; 772 } 773 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 774 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 775 rc = security_transition_sid(current_sid(), 776 current_sid(), 777 SECCLASS_FILE, NULL, 778 &sbsec->mntpoint_sid); 779 if (rc) 780 goto out; 781 } 782 goto out_set_opts; 783 } 784 785 /* sets the context of the superblock for the fs being mounted. */ 786 if (fscontext_sid) { 787 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 788 if (rc) 789 goto out; 790 791 sbsec->sid = fscontext_sid; 792 } 793 794 /* 795 * Switch to using mount point labeling behavior. 796 * sets the label used on all file below the mountpoint, and will set 797 * the superblock context if not already set. 798 */ 799 if (sbsec->flags & SE_SBNATIVE) { 800 /* 801 * This means we are initializing a superblock that has been 802 * mounted before the SELinux was initialized and the 803 * filesystem requested native labeling. We had already 804 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags 805 * in the original mount attempt, so now we just need to set 806 * the SECURITY_FS_USE_NATIVE behavior. 807 */ 808 sbsec->behavior = SECURITY_FS_USE_NATIVE; 809 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 810 sbsec->behavior = SECURITY_FS_USE_NATIVE; 811 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 812 } 813 814 if (context_sid) { 815 if (!fscontext_sid) { 816 rc = may_context_mount_sb_relabel(context_sid, sbsec, 817 cred); 818 if (rc) 819 goto out; 820 sbsec->sid = context_sid; 821 } else { 822 rc = may_context_mount_inode_relabel(context_sid, sbsec, 823 cred); 824 if (rc) 825 goto out; 826 } 827 if (!rootcontext_sid) 828 rootcontext_sid = context_sid; 829 830 sbsec->mntpoint_sid = context_sid; 831 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 832 } 833 834 if (rootcontext_sid) { 835 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 836 cred); 837 if (rc) 838 goto out; 839 840 root_isec->sid = rootcontext_sid; 841 root_isec->initialized = LABEL_INITIALIZED; 842 } 843 844 if (defcontext_sid) { 845 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 846 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 847 rc = -EINVAL; 848 pr_warn("SELinux: defcontext option is " 849 "invalid for this filesystem type\n"); 850 goto out; 851 } 852 853 if (defcontext_sid != sbsec->def_sid) { 854 rc = may_context_mount_inode_relabel(defcontext_sid, 855 sbsec, cred); 856 if (rc) 857 goto out; 858 } 859 860 sbsec->def_sid = defcontext_sid; 861 } 862 863 out_set_opts: 864 rc = sb_finish_set_opts(sb); 865 out: 866 mutex_unlock(&sbsec->lock); 867 return rc; 868 out_double_mount: 869 rc = -EINVAL; 870 pr_warn("SELinux: mount invalid. Same superblock, different " 871 "security settings for (dev %s, type %s)\n", sb->s_id, 872 sb->s_type->name); 873 goto out; 874 } 875 876 static int selinux_cmp_sb_context(const struct super_block *oldsb, 877 const struct super_block *newsb) 878 { 879 struct superblock_security_struct *old = selinux_superblock(oldsb); 880 struct superblock_security_struct *new = selinux_superblock(newsb); 881 char oldflags = old->flags & SE_MNTMASK; 882 char newflags = new->flags & SE_MNTMASK; 883 884 if (oldflags != newflags) 885 goto mismatch; 886 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 887 goto mismatch; 888 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 889 goto mismatch; 890 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 891 goto mismatch; 892 if (oldflags & ROOTCONTEXT_MNT) { 893 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 894 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 895 if (oldroot->sid != newroot->sid) 896 goto mismatch; 897 } 898 return 0; 899 mismatch: 900 pr_warn("SELinux: mount invalid. Same superblock, " 901 "different security settings for (dev %s, " 902 "type %s)\n", newsb->s_id, newsb->s_type->name); 903 return -EBUSY; 904 } 905 906 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 907 struct super_block *newsb, 908 unsigned long kern_flags, 909 unsigned long *set_kern_flags) 910 { 911 int rc = 0; 912 const struct superblock_security_struct *oldsbsec = 913 selinux_superblock(oldsb); 914 struct superblock_security_struct *newsbsec = selinux_superblock(newsb); 915 916 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 917 int set_context = (oldsbsec->flags & CONTEXT_MNT); 918 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 919 920 /* 921 * Specifying internal flags without providing a place to 922 * place the results is not allowed. 923 */ 924 if (kern_flags && !set_kern_flags) 925 return -EINVAL; 926 927 mutex_lock(&newsbsec->lock); 928 929 /* 930 * if the parent was able to be mounted it clearly had no special lsm 931 * mount options. thus we can safely deal with this superblock later 932 */ 933 if (!selinux_initialized()) { 934 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 935 newsbsec->flags |= SE_SBNATIVE; 936 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 937 } 938 goto out; 939 } 940 941 /* how can we clone if the old one wasn't set up?? */ 942 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 943 944 /* if fs is reusing a sb, make sure that the contexts match */ 945 if (newsbsec->flags & SE_SBINITIALIZED) { 946 mutex_unlock(&newsbsec->lock); 947 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 948 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 949 return selinux_cmp_sb_context(oldsb, newsb); 950 } 951 952 newsbsec->flags = oldsbsec->flags; 953 954 newsbsec->sid = oldsbsec->sid; 955 newsbsec->def_sid = oldsbsec->def_sid; 956 newsbsec->behavior = oldsbsec->behavior; 957 958 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 959 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 960 rc = security_fs_use(newsb); 961 if (rc) 962 goto out; 963 } 964 965 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 966 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 967 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 968 } 969 970 if (set_context) { 971 u32 sid = oldsbsec->mntpoint_sid; 972 973 if (!set_fscontext) 974 newsbsec->sid = sid; 975 if (!set_rootcontext) { 976 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 977 newisec->sid = sid; 978 } 979 newsbsec->mntpoint_sid = sid; 980 } 981 if (set_rootcontext) { 982 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 983 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 984 985 newisec->sid = oldisec->sid; 986 } 987 988 sb_finish_set_opts(newsb); 989 out: 990 mutex_unlock(&newsbsec->lock); 991 return rc; 992 } 993 994 /* 995 * NOTE: the caller is responsible for freeing the memory even if on error. 996 */ 997 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 998 { 999 struct selinux_mnt_opts *opts = *mnt_opts; 1000 u32 *dst_sid; 1001 int rc; 1002 1003 if (token == Opt_seclabel) 1004 /* eaten and completely ignored */ 1005 return 0; 1006 if (!s) 1007 return -EINVAL; 1008 1009 if (!selinux_initialized()) { 1010 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); 1011 return -EINVAL; 1012 } 1013 1014 if (!opts) { 1015 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 1016 if (!opts) 1017 return -ENOMEM; 1018 *mnt_opts = opts; 1019 } 1020 1021 switch (token) { 1022 case Opt_context: 1023 if (opts->context_sid || opts->defcontext_sid) 1024 goto err; 1025 dst_sid = &opts->context_sid; 1026 break; 1027 case Opt_fscontext: 1028 if (opts->fscontext_sid) 1029 goto err; 1030 dst_sid = &opts->fscontext_sid; 1031 break; 1032 case Opt_rootcontext: 1033 if (opts->rootcontext_sid) 1034 goto err; 1035 dst_sid = &opts->rootcontext_sid; 1036 break; 1037 case Opt_defcontext: 1038 if (opts->context_sid || opts->defcontext_sid) 1039 goto err; 1040 dst_sid = &opts->defcontext_sid; 1041 break; 1042 default: 1043 WARN_ON(1); 1044 return -EINVAL; 1045 } 1046 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); 1047 if (rc) 1048 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", 1049 s, rc); 1050 return rc; 1051 1052 err: 1053 pr_warn(SEL_MOUNT_FAIL_MSG); 1054 return -EINVAL; 1055 } 1056 1057 static int show_sid(struct seq_file *m, u32 sid) 1058 { 1059 char *context = NULL; 1060 u32 len; 1061 int rc; 1062 1063 rc = security_sid_to_context(sid, &context, &len); 1064 if (!rc) { 1065 bool has_comma = strchr(context, ','); 1066 1067 seq_putc(m, '='); 1068 if (has_comma) 1069 seq_putc(m, '\"'); 1070 seq_escape(m, context, "\"\n\\"); 1071 if (has_comma) 1072 seq_putc(m, '\"'); 1073 } 1074 kfree(context); 1075 return rc; 1076 } 1077 1078 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1079 { 1080 struct superblock_security_struct *sbsec = selinux_superblock(sb); 1081 int rc; 1082 1083 if (!(sbsec->flags & SE_SBINITIALIZED)) 1084 return 0; 1085 1086 if (!selinux_initialized()) 1087 return 0; 1088 1089 if (sbsec->flags & FSCONTEXT_MNT) { 1090 seq_putc(m, ','); 1091 seq_puts(m, FSCONTEXT_STR); 1092 rc = show_sid(m, sbsec->sid); 1093 if (rc) 1094 return rc; 1095 } 1096 if (sbsec->flags & CONTEXT_MNT) { 1097 seq_putc(m, ','); 1098 seq_puts(m, CONTEXT_STR); 1099 rc = show_sid(m, sbsec->mntpoint_sid); 1100 if (rc) 1101 return rc; 1102 } 1103 if (sbsec->flags & DEFCONTEXT_MNT) { 1104 seq_putc(m, ','); 1105 seq_puts(m, DEFCONTEXT_STR); 1106 rc = show_sid(m, sbsec->def_sid); 1107 if (rc) 1108 return rc; 1109 } 1110 if (sbsec->flags & ROOTCONTEXT_MNT) { 1111 struct dentry *root = sb->s_root; 1112 struct inode_security_struct *isec = backing_inode_security(root); 1113 seq_putc(m, ','); 1114 seq_puts(m, ROOTCONTEXT_STR); 1115 rc = show_sid(m, isec->sid); 1116 if (rc) 1117 return rc; 1118 } 1119 if (sbsec->flags & SBLABEL_MNT) { 1120 seq_putc(m, ','); 1121 seq_puts(m, SECLABEL_STR); 1122 } 1123 return 0; 1124 } 1125 1126 static inline u16 inode_mode_to_security_class(umode_t mode) 1127 { 1128 switch (mode & S_IFMT) { 1129 case S_IFSOCK: 1130 return SECCLASS_SOCK_FILE; 1131 case S_IFLNK: 1132 return SECCLASS_LNK_FILE; 1133 case S_IFREG: 1134 return SECCLASS_FILE; 1135 case S_IFBLK: 1136 return SECCLASS_BLK_FILE; 1137 case S_IFDIR: 1138 return SECCLASS_DIR; 1139 case S_IFCHR: 1140 return SECCLASS_CHR_FILE; 1141 case S_IFIFO: 1142 return SECCLASS_FIFO_FILE; 1143 1144 } 1145 1146 return SECCLASS_FILE; 1147 } 1148 1149 static inline int default_protocol_stream(int protocol) 1150 { 1151 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || 1152 protocol == IPPROTO_MPTCP); 1153 } 1154 1155 static inline int default_protocol_dgram(int protocol) 1156 { 1157 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1158 } 1159 1160 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1161 { 1162 bool extsockclass = selinux_policycap_extsockclass(); 1163 1164 switch (family) { 1165 case PF_UNIX: 1166 switch (type) { 1167 case SOCK_STREAM: 1168 case SOCK_SEQPACKET: 1169 return SECCLASS_UNIX_STREAM_SOCKET; 1170 case SOCK_DGRAM: 1171 case SOCK_RAW: 1172 return SECCLASS_UNIX_DGRAM_SOCKET; 1173 } 1174 break; 1175 case PF_INET: 1176 case PF_INET6: 1177 switch (type) { 1178 case SOCK_STREAM: 1179 case SOCK_SEQPACKET: 1180 if (default_protocol_stream(protocol)) 1181 return SECCLASS_TCP_SOCKET; 1182 else if (extsockclass && protocol == IPPROTO_SCTP) 1183 return SECCLASS_SCTP_SOCKET; 1184 else 1185 return SECCLASS_RAWIP_SOCKET; 1186 case SOCK_DGRAM: 1187 if (default_protocol_dgram(protocol)) 1188 return SECCLASS_UDP_SOCKET; 1189 else if (extsockclass && (protocol == IPPROTO_ICMP || 1190 protocol == IPPROTO_ICMPV6)) 1191 return SECCLASS_ICMP_SOCKET; 1192 else 1193 return SECCLASS_RAWIP_SOCKET; 1194 case SOCK_DCCP: 1195 return SECCLASS_DCCP_SOCKET; 1196 default: 1197 return SECCLASS_RAWIP_SOCKET; 1198 } 1199 break; 1200 case PF_NETLINK: 1201 switch (protocol) { 1202 case NETLINK_ROUTE: 1203 return SECCLASS_NETLINK_ROUTE_SOCKET; 1204 case NETLINK_SOCK_DIAG: 1205 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1206 case NETLINK_NFLOG: 1207 return SECCLASS_NETLINK_NFLOG_SOCKET; 1208 case NETLINK_XFRM: 1209 return SECCLASS_NETLINK_XFRM_SOCKET; 1210 case NETLINK_SELINUX: 1211 return SECCLASS_NETLINK_SELINUX_SOCKET; 1212 case NETLINK_ISCSI: 1213 return SECCLASS_NETLINK_ISCSI_SOCKET; 1214 case NETLINK_AUDIT: 1215 return SECCLASS_NETLINK_AUDIT_SOCKET; 1216 case NETLINK_FIB_LOOKUP: 1217 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1218 case NETLINK_CONNECTOR: 1219 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1220 case NETLINK_NETFILTER: 1221 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1222 case NETLINK_DNRTMSG: 1223 return SECCLASS_NETLINK_DNRT_SOCKET; 1224 case NETLINK_KOBJECT_UEVENT: 1225 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1226 case NETLINK_GENERIC: 1227 return SECCLASS_NETLINK_GENERIC_SOCKET; 1228 case NETLINK_SCSITRANSPORT: 1229 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1230 case NETLINK_RDMA: 1231 return SECCLASS_NETLINK_RDMA_SOCKET; 1232 case NETLINK_CRYPTO: 1233 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1234 default: 1235 return SECCLASS_NETLINK_SOCKET; 1236 } 1237 case PF_PACKET: 1238 return SECCLASS_PACKET_SOCKET; 1239 case PF_KEY: 1240 return SECCLASS_KEY_SOCKET; 1241 case PF_APPLETALK: 1242 return SECCLASS_APPLETALK_SOCKET; 1243 } 1244 1245 if (extsockclass) { 1246 switch (family) { 1247 case PF_AX25: 1248 return SECCLASS_AX25_SOCKET; 1249 case PF_IPX: 1250 return SECCLASS_IPX_SOCKET; 1251 case PF_NETROM: 1252 return SECCLASS_NETROM_SOCKET; 1253 case PF_ATMPVC: 1254 return SECCLASS_ATMPVC_SOCKET; 1255 case PF_X25: 1256 return SECCLASS_X25_SOCKET; 1257 case PF_ROSE: 1258 return SECCLASS_ROSE_SOCKET; 1259 case PF_DECnet: 1260 return SECCLASS_DECNET_SOCKET; 1261 case PF_ATMSVC: 1262 return SECCLASS_ATMSVC_SOCKET; 1263 case PF_RDS: 1264 return SECCLASS_RDS_SOCKET; 1265 case PF_IRDA: 1266 return SECCLASS_IRDA_SOCKET; 1267 case PF_PPPOX: 1268 return SECCLASS_PPPOX_SOCKET; 1269 case PF_LLC: 1270 return SECCLASS_LLC_SOCKET; 1271 case PF_CAN: 1272 return SECCLASS_CAN_SOCKET; 1273 case PF_TIPC: 1274 return SECCLASS_TIPC_SOCKET; 1275 case PF_BLUETOOTH: 1276 return SECCLASS_BLUETOOTH_SOCKET; 1277 case PF_IUCV: 1278 return SECCLASS_IUCV_SOCKET; 1279 case PF_RXRPC: 1280 return SECCLASS_RXRPC_SOCKET; 1281 case PF_ISDN: 1282 return SECCLASS_ISDN_SOCKET; 1283 case PF_PHONET: 1284 return SECCLASS_PHONET_SOCKET; 1285 case PF_IEEE802154: 1286 return SECCLASS_IEEE802154_SOCKET; 1287 case PF_CAIF: 1288 return SECCLASS_CAIF_SOCKET; 1289 case PF_ALG: 1290 return SECCLASS_ALG_SOCKET; 1291 case PF_NFC: 1292 return SECCLASS_NFC_SOCKET; 1293 case PF_VSOCK: 1294 return SECCLASS_VSOCK_SOCKET; 1295 case PF_KCM: 1296 return SECCLASS_KCM_SOCKET; 1297 case PF_QIPCRTR: 1298 return SECCLASS_QIPCRTR_SOCKET; 1299 case PF_SMC: 1300 return SECCLASS_SMC_SOCKET; 1301 case PF_XDP: 1302 return SECCLASS_XDP_SOCKET; 1303 case PF_MCTP: 1304 return SECCLASS_MCTP_SOCKET; 1305 #if PF_MAX > 46 1306 #error New address family defined, please update this function. 1307 #endif 1308 } 1309 } 1310 1311 return SECCLASS_SOCKET; 1312 } 1313 1314 static int selinux_genfs_get_sid(struct dentry *dentry, 1315 u16 tclass, 1316 u16 flags, 1317 u32 *sid) 1318 { 1319 int rc; 1320 struct super_block *sb = dentry->d_sb; 1321 char *buffer, *path; 1322 1323 buffer = (char *)__get_free_page(GFP_KERNEL); 1324 if (!buffer) 1325 return -ENOMEM; 1326 1327 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1328 if (IS_ERR(path)) 1329 rc = PTR_ERR(path); 1330 else { 1331 if (flags & SE_SBPROC) { 1332 /* each process gets a /proc/PID/ entry. Strip off the 1333 * PID part to get a valid selinux labeling. 1334 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1335 while (path[1] >= '0' && path[1] <= '9') { 1336 path[1] = '/'; 1337 path++; 1338 } 1339 } 1340 rc = security_genfs_sid(sb->s_type->name, 1341 path, tclass, sid); 1342 if (rc == -ENOENT) { 1343 /* No match in policy, mark as unlabeled. */ 1344 *sid = SECINITSID_UNLABELED; 1345 rc = 0; 1346 } 1347 } 1348 free_page((unsigned long)buffer); 1349 return rc; 1350 } 1351 1352 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1353 u32 def_sid, u32 *sid) 1354 { 1355 #define INITCONTEXTLEN 255 1356 char *context; 1357 unsigned int len; 1358 int rc; 1359 1360 len = INITCONTEXTLEN; 1361 context = kmalloc(len + 1, GFP_NOFS); 1362 if (!context) 1363 return -ENOMEM; 1364 1365 context[len] = '\0'; 1366 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1367 if (rc == -ERANGE) { 1368 kfree(context); 1369 1370 /* Need a larger buffer. Query for the right size. */ 1371 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1372 if (rc < 0) 1373 return rc; 1374 1375 len = rc; 1376 context = kmalloc(len + 1, GFP_NOFS); 1377 if (!context) 1378 return -ENOMEM; 1379 1380 context[len] = '\0'; 1381 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1382 context, len); 1383 } 1384 if (rc < 0) { 1385 kfree(context); 1386 if (rc != -ENODATA) { 1387 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1388 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1389 return rc; 1390 } 1391 *sid = def_sid; 1392 return 0; 1393 } 1394 1395 rc = security_context_to_sid_default(context, rc, sid, 1396 def_sid, GFP_NOFS); 1397 if (rc) { 1398 char *dev = inode->i_sb->s_id; 1399 unsigned long ino = inode->i_ino; 1400 1401 if (rc == -EINVAL) { 1402 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", 1403 ino, dev, context); 1404 } else { 1405 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1406 __func__, context, -rc, dev, ino); 1407 } 1408 } 1409 kfree(context); 1410 return 0; 1411 } 1412 1413 /* The inode's security attributes must be initialized before first use. */ 1414 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1415 { 1416 struct superblock_security_struct *sbsec = NULL; 1417 struct inode_security_struct *isec = selinux_inode(inode); 1418 u32 task_sid, sid = 0; 1419 u16 sclass; 1420 struct dentry *dentry; 1421 int rc = 0; 1422 1423 if (isec->initialized == LABEL_INITIALIZED) 1424 return 0; 1425 1426 spin_lock(&isec->lock); 1427 if (isec->initialized == LABEL_INITIALIZED) 1428 goto out_unlock; 1429 1430 if (isec->sclass == SECCLASS_FILE) 1431 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1432 1433 sbsec = selinux_superblock(inode->i_sb); 1434 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1435 /* Defer initialization until selinux_complete_init, 1436 after the initial policy is loaded and the security 1437 server is ready to handle calls. */ 1438 spin_lock(&sbsec->isec_lock); 1439 if (list_empty(&isec->list)) 1440 list_add(&isec->list, &sbsec->isec_head); 1441 spin_unlock(&sbsec->isec_lock); 1442 goto out_unlock; 1443 } 1444 1445 sclass = isec->sclass; 1446 task_sid = isec->task_sid; 1447 sid = isec->sid; 1448 isec->initialized = LABEL_PENDING; 1449 spin_unlock(&isec->lock); 1450 1451 switch (sbsec->behavior) { 1452 /* 1453 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels 1454 * via xattr when called from delayed_superblock_init(). 1455 */ 1456 case SECURITY_FS_USE_NATIVE: 1457 case SECURITY_FS_USE_XATTR: 1458 if (!(inode->i_opflags & IOP_XATTR)) { 1459 sid = sbsec->def_sid; 1460 break; 1461 } 1462 /* Need a dentry, since the xattr API requires one. 1463 Life would be simpler if we could just pass the inode. */ 1464 if (opt_dentry) { 1465 /* Called from d_instantiate or d_splice_alias. */ 1466 dentry = dget(opt_dentry); 1467 } else { 1468 /* 1469 * Called from selinux_complete_init, try to find a dentry. 1470 * Some filesystems really want a connected one, so try 1471 * that first. We could split SECURITY_FS_USE_XATTR in 1472 * two, depending upon that... 1473 */ 1474 dentry = d_find_alias(inode); 1475 if (!dentry) 1476 dentry = d_find_any_alias(inode); 1477 } 1478 if (!dentry) { 1479 /* 1480 * this is can be hit on boot when a file is accessed 1481 * before the policy is loaded. When we load policy we 1482 * may find inodes that have no dentry on the 1483 * sbsec->isec_head list. No reason to complain as these 1484 * will get fixed up the next time we go through 1485 * inode_doinit with a dentry, before these inodes could 1486 * be used again by userspace. 1487 */ 1488 goto out_invalid; 1489 } 1490 1491 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1492 &sid); 1493 dput(dentry); 1494 if (rc) 1495 goto out; 1496 break; 1497 case SECURITY_FS_USE_TASK: 1498 sid = task_sid; 1499 break; 1500 case SECURITY_FS_USE_TRANS: 1501 /* Default to the fs SID. */ 1502 sid = sbsec->sid; 1503 1504 /* Try to obtain a transition SID. */ 1505 rc = security_transition_sid(task_sid, sid, 1506 sclass, NULL, &sid); 1507 if (rc) 1508 goto out; 1509 break; 1510 case SECURITY_FS_USE_MNTPOINT: 1511 sid = sbsec->mntpoint_sid; 1512 break; 1513 default: 1514 /* Default to the fs superblock SID. */ 1515 sid = sbsec->sid; 1516 1517 if ((sbsec->flags & SE_SBGENFS) && 1518 (!S_ISLNK(inode->i_mode) || 1519 selinux_policycap_genfs_seclabel_symlinks())) { 1520 /* We must have a dentry to determine the label on 1521 * procfs inodes */ 1522 if (opt_dentry) { 1523 /* Called from d_instantiate or 1524 * d_splice_alias. */ 1525 dentry = dget(opt_dentry); 1526 } else { 1527 /* Called from selinux_complete_init, try to 1528 * find a dentry. Some filesystems really want 1529 * a connected one, so try that first. 1530 */ 1531 dentry = d_find_alias(inode); 1532 if (!dentry) 1533 dentry = d_find_any_alias(inode); 1534 } 1535 /* 1536 * This can be hit on boot when a file is accessed 1537 * before the policy is loaded. When we load policy we 1538 * may find inodes that have no dentry on the 1539 * sbsec->isec_head list. No reason to complain as 1540 * these will get fixed up the next time we go through 1541 * inode_doinit() with a dentry, before these inodes 1542 * could be used again by userspace. 1543 */ 1544 if (!dentry) 1545 goto out_invalid; 1546 rc = selinux_genfs_get_sid(dentry, sclass, 1547 sbsec->flags, &sid); 1548 if (rc) { 1549 dput(dentry); 1550 goto out; 1551 } 1552 1553 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1554 (inode->i_opflags & IOP_XATTR)) { 1555 rc = inode_doinit_use_xattr(inode, dentry, 1556 sid, &sid); 1557 if (rc) { 1558 dput(dentry); 1559 goto out; 1560 } 1561 } 1562 dput(dentry); 1563 } 1564 break; 1565 } 1566 1567 out: 1568 spin_lock(&isec->lock); 1569 if (isec->initialized == LABEL_PENDING) { 1570 if (rc) { 1571 isec->initialized = LABEL_INVALID; 1572 goto out_unlock; 1573 } 1574 isec->initialized = LABEL_INITIALIZED; 1575 isec->sid = sid; 1576 } 1577 1578 out_unlock: 1579 spin_unlock(&isec->lock); 1580 return rc; 1581 1582 out_invalid: 1583 spin_lock(&isec->lock); 1584 if (isec->initialized == LABEL_PENDING) { 1585 isec->initialized = LABEL_INVALID; 1586 isec->sid = sid; 1587 } 1588 spin_unlock(&isec->lock); 1589 return 0; 1590 } 1591 1592 /* Convert a Linux signal to an access vector. */ 1593 static inline u32 signal_to_av(int sig) 1594 { 1595 u32 perm = 0; 1596 1597 switch (sig) { 1598 case SIGCHLD: 1599 /* Commonly granted from child to parent. */ 1600 perm = PROCESS__SIGCHLD; 1601 break; 1602 case SIGKILL: 1603 /* Cannot be caught or ignored */ 1604 perm = PROCESS__SIGKILL; 1605 break; 1606 case SIGSTOP: 1607 /* Cannot be caught or ignored */ 1608 perm = PROCESS__SIGSTOP; 1609 break; 1610 default: 1611 /* All other signals. */ 1612 perm = PROCESS__SIGNAL; 1613 break; 1614 } 1615 1616 return perm; 1617 } 1618 1619 #if CAP_LAST_CAP > 63 1620 #error Fix SELinux to handle capabilities > 63. 1621 #endif 1622 1623 /* Check whether a task is allowed to use a capability. */ 1624 static int cred_has_capability(const struct cred *cred, 1625 int cap, unsigned int opts, bool initns) 1626 { 1627 struct common_audit_data ad; 1628 struct av_decision avd; 1629 u16 sclass; 1630 u32 sid = cred_sid(cred); 1631 u32 av = CAP_TO_MASK(cap); 1632 int rc; 1633 1634 ad.type = LSM_AUDIT_DATA_CAP; 1635 ad.u.cap = cap; 1636 1637 switch (CAP_TO_INDEX(cap)) { 1638 case 0: 1639 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1640 break; 1641 case 1: 1642 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1643 break; 1644 default: 1645 pr_err("SELinux: out of range capability %d\n", cap); 1646 BUG(); 1647 return -EINVAL; 1648 } 1649 1650 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1651 if (!(opts & CAP_OPT_NOAUDIT)) { 1652 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1653 if (rc2) 1654 return rc2; 1655 } 1656 return rc; 1657 } 1658 1659 /* Check whether a task has a particular permission to an inode. 1660 The 'adp' parameter is optional and allows other audit 1661 data to be passed (e.g. the dentry). */ 1662 static int inode_has_perm(const struct cred *cred, 1663 struct inode *inode, 1664 u32 perms, 1665 struct common_audit_data *adp) 1666 { 1667 struct inode_security_struct *isec; 1668 u32 sid; 1669 1670 if (unlikely(IS_PRIVATE(inode))) 1671 return 0; 1672 1673 sid = cred_sid(cred); 1674 isec = selinux_inode(inode); 1675 1676 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1677 } 1678 1679 /* Same as inode_has_perm, but pass explicit audit data containing 1680 the dentry to help the auditing code to more easily generate the 1681 pathname if needed. */ 1682 static inline int dentry_has_perm(const struct cred *cred, 1683 struct dentry *dentry, 1684 u32 av) 1685 { 1686 struct inode *inode = d_backing_inode(dentry); 1687 struct common_audit_data ad; 1688 1689 ad.type = LSM_AUDIT_DATA_DENTRY; 1690 ad.u.dentry = dentry; 1691 __inode_security_revalidate(inode, dentry, true); 1692 return inode_has_perm(cred, inode, av, &ad); 1693 } 1694 1695 /* Same as inode_has_perm, but pass explicit audit data containing 1696 the path to help the auditing code to more easily generate the 1697 pathname if needed. */ 1698 static inline int path_has_perm(const struct cred *cred, 1699 const struct path *path, 1700 u32 av) 1701 { 1702 struct inode *inode = d_backing_inode(path->dentry); 1703 struct common_audit_data ad; 1704 1705 ad.type = LSM_AUDIT_DATA_PATH; 1706 ad.u.path = *path; 1707 __inode_security_revalidate(inode, path->dentry, true); 1708 return inode_has_perm(cred, inode, av, &ad); 1709 } 1710 1711 /* Same as path_has_perm, but uses the inode from the file struct. */ 1712 static inline int file_path_has_perm(const struct cred *cred, 1713 struct file *file, 1714 u32 av) 1715 { 1716 struct common_audit_data ad; 1717 1718 ad.type = LSM_AUDIT_DATA_FILE; 1719 ad.u.file = file; 1720 return inode_has_perm(cred, file_inode(file), av, &ad); 1721 } 1722 1723 #ifdef CONFIG_BPF_SYSCALL 1724 static int bpf_fd_pass(const struct file *file, u32 sid); 1725 #endif 1726 1727 /* Check whether a task can use an open file descriptor to 1728 access an inode in a given way. Check access to the 1729 descriptor itself, and then use dentry_has_perm to 1730 check a particular permission to the file. 1731 Access to the descriptor is implicitly granted if it 1732 has the same SID as the process. If av is zero, then 1733 access to the file is not checked, e.g. for cases 1734 where only the descriptor is affected like seek. */ 1735 static int file_has_perm(const struct cred *cred, 1736 struct file *file, 1737 u32 av) 1738 { 1739 struct file_security_struct *fsec = selinux_file(file); 1740 struct inode *inode = file_inode(file); 1741 struct common_audit_data ad; 1742 u32 sid = cred_sid(cred); 1743 int rc; 1744 1745 ad.type = LSM_AUDIT_DATA_FILE; 1746 ad.u.file = file; 1747 1748 if (sid != fsec->sid) { 1749 rc = avc_has_perm(sid, fsec->sid, 1750 SECCLASS_FD, 1751 FD__USE, 1752 &ad); 1753 if (rc) 1754 goto out; 1755 } 1756 1757 #ifdef CONFIG_BPF_SYSCALL 1758 rc = bpf_fd_pass(file, cred_sid(cred)); 1759 if (rc) 1760 return rc; 1761 #endif 1762 1763 /* av is zero if only checking access to the descriptor. */ 1764 rc = 0; 1765 if (av) 1766 rc = inode_has_perm(cred, inode, av, &ad); 1767 1768 out: 1769 return rc; 1770 } 1771 1772 /* 1773 * Determine the label for an inode that might be unioned. 1774 */ 1775 static int 1776 selinux_determine_inode_label(const struct task_security_struct *tsec, 1777 struct inode *dir, 1778 const struct qstr *name, u16 tclass, 1779 u32 *_new_isid) 1780 { 1781 const struct superblock_security_struct *sbsec = 1782 selinux_superblock(dir->i_sb); 1783 1784 if ((sbsec->flags & SE_SBINITIALIZED) && 1785 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1786 *_new_isid = sbsec->mntpoint_sid; 1787 } else if ((sbsec->flags & SBLABEL_MNT) && 1788 tsec->create_sid) { 1789 *_new_isid = tsec->create_sid; 1790 } else { 1791 const struct inode_security_struct *dsec = inode_security(dir); 1792 return security_transition_sid(tsec->sid, 1793 dsec->sid, tclass, 1794 name, _new_isid); 1795 } 1796 1797 return 0; 1798 } 1799 1800 /* Check whether a task can create a file. */ 1801 static int may_create(struct inode *dir, 1802 struct dentry *dentry, 1803 u16 tclass) 1804 { 1805 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1806 struct inode_security_struct *dsec; 1807 struct superblock_security_struct *sbsec; 1808 u32 sid, newsid; 1809 struct common_audit_data ad; 1810 int rc; 1811 1812 dsec = inode_security(dir); 1813 sbsec = selinux_superblock(dir->i_sb); 1814 1815 sid = tsec->sid; 1816 1817 ad.type = LSM_AUDIT_DATA_DENTRY; 1818 ad.u.dentry = dentry; 1819 1820 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1821 DIR__ADD_NAME | DIR__SEARCH, 1822 &ad); 1823 if (rc) 1824 return rc; 1825 1826 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1827 &newsid); 1828 if (rc) 1829 return rc; 1830 1831 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1832 if (rc) 1833 return rc; 1834 1835 return avc_has_perm(newsid, sbsec->sid, 1836 SECCLASS_FILESYSTEM, 1837 FILESYSTEM__ASSOCIATE, &ad); 1838 } 1839 1840 #define MAY_LINK 0 1841 #define MAY_UNLINK 1 1842 #define MAY_RMDIR 2 1843 1844 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1845 static int may_link(struct inode *dir, 1846 struct dentry *dentry, 1847 int kind) 1848 1849 { 1850 struct inode_security_struct *dsec, *isec; 1851 struct common_audit_data ad; 1852 u32 sid = current_sid(); 1853 u32 av; 1854 int rc; 1855 1856 dsec = inode_security(dir); 1857 isec = backing_inode_security(dentry); 1858 1859 ad.type = LSM_AUDIT_DATA_DENTRY; 1860 ad.u.dentry = dentry; 1861 1862 av = DIR__SEARCH; 1863 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1864 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1865 if (rc) 1866 return rc; 1867 1868 switch (kind) { 1869 case MAY_LINK: 1870 av = FILE__LINK; 1871 break; 1872 case MAY_UNLINK: 1873 av = FILE__UNLINK; 1874 break; 1875 case MAY_RMDIR: 1876 av = DIR__RMDIR; 1877 break; 1878 default: 1879 pr_warn("SELinux: %s: unrecognized kind %d\n", 1880 __func__, kind); 1881 return 0; 1882 } 1883 1884 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1885 return rc; 1886 } 1887 1888 static inline int may_rename(struct inode *old_dir, 1889 struct dentry *old_dentry, 1890 struct inode *new_dir, 1891 struct dentry *new_dentry) 1892 { 1893 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1894 struct common_audit_data ad; 1895 u32 sid = current_sid(); 1896 u32 av; 1897 int old_is_dir, new_is_dir; 1898 int rc; 1899 1900 old_dsec = inode_security(old_dir); 1901 old_isec = backing_inode_security(old_dentry); 1902 old_is_dir = d_is_dir(old_dentry); 1903 new_dsec = inode_security(new_dir); 1904 1905 ad.type = LSM_AUDIT_DATA_DENTRY; 1906 1907 ad.u.dentry = old_dentry; 1908 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1909 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1910 if (rc) 1911 return rc; 1912 rc = avc_has_perm(sid, old_isec->sid, 1913 old_isec->sclass, FILE__RENAME, &ad); 1914 if (rc) 1915 return rc; 1916 if (old_is_dir && new_dir != old_dir) { 1917 rc = avc_has_perm(sid, old_isec->sid, 1918 old_isec->sclass, DIR__REPARENT, &ad); 1919 if (rc) 1920 return rc; 1921 } 1922 1923 ad.u.dentry = new_dentry; 1924 av = DIR__ADD_NAME | DIR__SEARCH; 1925 if (d_is_positive(new_dentry)) 1926 av |= DIR__REMOVE_NAME; 1927 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1928 if (rc) 1929 return rc; 1930 if (d_is_positive(new_dentry)) { 1931 new_isec = backing_inode_security(new_dentry); 1932 new_is_dir = d_is_dir(new_dentry); 1933 rc = avc_has_perm(sid, new_isec->sid, 1934 new_isec->sclass, 1935 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1936 if (rc) 1937 return rc; 1938 } 1939 1940 return 0; 1941 } 1942 1943 /* Check whether a task can perform a filesystem operation. */ 1944 static int superblock_has_perm(const struct cred *cred, 1945 const struct super_block *sb, 1946 u32 perms, 1947 struct common_audit_data *ad) 1948 { 1949 struct superblock_security_struct *sbsec; 1950 u32 sid = cred_sid(cred); 1951 1952 sbsec = selinux_superblock(sb); 1953 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1954 } 1955 1956 /* Convert a Linux mode and permission mask to an access vector. */ 1957 static inline u32 file_mask_to_av(int mode, int mask) 1958 { 1959 u32 av = 0; 1960 1961 if (!S_ISDIR(mode)) { 1962 if (mask & MAY_EXEC) 1963 av |= FILE__EXECUTE; 1964 if (mask & MAY_READ) 1965 av |= FILE__READ; 1966 1967 if (mask & MAY_APPEND) 1968 av |= FILE__APPEND; 1969 else if (mask & MAY_WRITE) 1970 av |= FILE__WRITE; 1971 1972 } else { 1973 if (mask & MAY_EXEC) 1974 av |= DIR__SEARCH; 1975 if (mask & MAY_WRITE) 1976 av |= DIR__WRITE; 1977 if (mask & MAY_READ) 1978 av |= DIR__READ; 1979 } 1980 1981 return av; 1982 } 1983 1984 /* Convert a Linux file to an access vector. */ 1985 static inline u32 file_to_av(const struct file *file) 1986 { 1987 u32 av = 0; 1988 1989 if (file->f_mode & FMODE_READ) 1990 av |= FILE__READ; 1991 if (file->f_mode & FMODE_WRITE) { 1992 if (file->f_flags & O_APPEND) 1993 av |= FILE__APPEND; 1994 else 1995 av |= FILE__WRITE; 1996 } 1997 if (!av) { 1998 /* 1999 * Special file opened with flags 3 for ioctl-only use. 2000 */ 2001 av = FILE__IOCTL; 2002 } 2003 2004 return av; 2005 } 2006 2007 /* 2008 * Convert a file to an access vector and include the correct 2009 * open permission. 2010 */ 2011 static inline u32 open_file_to_av(struct file *file) 2012 { 2013 u32 av = file_to_av(file); 2014 struct inode *inode = file_inode(file); 2015 2016 if (selinux_policycap_openperm() && 2017 inode->i_sb->s_magic != SOCKFS_MAGIC) 2018 av |= FILE__OPEN; 2019 2020 return av; 2021 } 2022 2023 /* Hook functions begin here. */ 2024 2025 static int selinux_binder_set_context_mgr(const struct cred *mgr) 2026 { 2027 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, 2028 BINDER__SET_CONTEXT_MGR, NULL); 2029 } 2030 2031 static int selinux_binder_transaction(const struct cred *from, 2032 const struct cred *to) 2033 { 2034 u32 mysid = current_sid(); 2035 u32 fromsid = cred_sid(from); 2036 u32 tosid = cred_sid(to); 2037 int rc; 2038 2039 if (mysid != fromsid) { 2040 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2041 BINDER__IMPERSONATE, NULL); 2042 if (rc) 2043 return rc; 2044 } 2045 2046 return avc_has_perm(fromsid, tosid, 2047 SECCLASS_BINDER, BINDER__CALL, NULL); 2048 } 2049 2050 static int selinux_binder_transfer_binder(const struct cred *from, 2051 const struct cred *to) 2052 { 2053 return avc_has_perm(cred_sid(from), cred_sid(to), 2054 SECCLASS_BINDER, BINDER__TRANSFER, 2055 NULL); 2056 } 2057 2058 static int selinux_binder_transfer_file(const struct cred *from, 2059 const struct cred *to, 2060 const struct file *file) 2061 { 2062 u32 sid = cred_sid(to); 2063 struct file_security_struct *fsec = selinux_file(file); 2064 struct dentry *dentry = file->f_path.dentry; 2065 struct inode_security_struct *isec; 2066 struct common_audit_data ad; 2067 int rc; 2068 2069 ad.type = LSM_AUDIT_DATA_PATH; 2070 ad.u.path = file->f_path; 2071 2072 if (sid != fsec->sid) { 2073 rc = avc_has_perm(sid, fsec->sid, 2074 SECCLASS_FD, 2075 FD__USE, 2076 &ad); 2077 if (rc) 2078 return rc; 2079 } 2080 2081 #ifdef CONFIG_BPF_SYSCALL 2082 rc = bpf_fd_pass(file, sid); 2083 if (rc) 2084 return rc; 2085 #endif 2086 2087 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2088 return 0; 2089 2090 isec = backing_inode_security(dentry); 2091 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2092 &ad); 2093 } 2094 2095 static int selinux_ptrace_access_check(struct task_struct *child, 2096 unsigned int mode) 2097 { 2098 u32 sid = current_sid(); 2099 u32 csid = task_sid_obj(child); 2100 2101 if (mode & PTRACE_MODE_READ) 2102 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, 2103 NULL); 2104 2105 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, 2106 NULL); 2107 } 2108 2109 static int selinux_ptrace_traceme(struct task_struct *parent) 2110 { 2111 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), 2112 SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2113 } 2114 2115 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, 2116 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2117 { 2118 return avc_has_perm(current_sid(), task_sid_obj(target), 2119 SECCLASS_PROCESS, PROCESS__GETCAP, NULL); 2120 } 2121 2122 static int selinux_capset(struct cred *new, const struct cred *old, 2123 const kernel_cap_t *effective, 2124 const kernel_cap_t *inheritable, 2125 const kernel_cap_t *permitted) 2126 { 2127 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2128 PROCESS__SETCAP, NULL); 2129 } 2130 2131 /* 2132 * (This comment used to live with the selinux_task_setuid hook, 2133 * which was removed). 2134 * 2135 * Since setuid only affects the current process, and since the SELinux 2136 * controls are not based on the Linux identity attributes, SELinux does not 2137 * need to control this operation. However, SELinux does control the use of 2138 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2139 */ 2140 2141 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2142 int cap, unsigned int opts) 2143 { 2144 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2145 } 2146 2147 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb) 2148 { 2149 const struct cred *cred = current_cred(); 2150 int rc = 0; 2151 2152 if (!sb) 2153 return 0; 2154 2155 switch (cmds) { 2156 case Q_SYNC: 2157 case Q_QUOTAON: 2158 case Q_QUOTAOFF: 2159 case Q_SETINFO: 2160 case Q_SETQUOTA: 2161 case Q_XQUOTAOFF: 2162 case Q_XQUOTAON: 2163 case Q_XSETQLIM: 2164 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2165 break; 2166 case Q_GETFMT: 2167 case Q_GETINFO: 2168 case Q_GETQUOTA: 2169 case Q_XGETQUOTA: 2170 case Q_XGETQSTAT: 2171 case Q_XGETQSTATV: 2172 case Q_XGETNEXTQUOTA: 2173 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2174 break; 2175 default: 2176 rc = 0; /* let the kernel handle invalid cmds */ 2177 break; 2178 } 2179 return rc; 2180 } 2181 2182 static int selinux_quota_on(struct dentry *dentry) 2183 { 2184 const struct cred *cred = current_cred(); 2185 2186 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2187 } 2188 2189 static int selinux_syslog(int type) 2190 { 2191 switch (type) { 2192 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2193 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2194 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2195 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2196 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2197 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2198 /* Set level of messages printed to console */ 2199 case SYSLOG_ACTION_CONSOLE_LEVEL: 2200 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2201 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2202 NULL); 2203 } 2204 /* All other syslog types */ 2205 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2206 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2207 } 2208 2209 /* 2210 * Check permission for allocating a new virtual mapping. Returns 2211 * 0 if permission is granted, negative error code if not. 2212 * 2213 * Do not audit the selinux permission check, as this is applied to all 2214 * processes that allocate mappings. 2215 */ 2216 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2217 { 2218 return cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2219 CAP_OPT_NOAUDIT, true); 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 /* 2317 * Before policy is loaded, label any task outside kernel space 2318 * as SECINITSID_INIT, so that any userspace tasks surviving from 2319 * early boot end up with a label different from SECINITSID_KERNEL 2320 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL). 2321 */ 2322 if (!selinux_initialized()) { 2323 new_tsec->sid = SECINITSID_INIT; 2324 /* also clear the exec_sid just in case */ 2325 new_tsec->exec_sid = 0; 2326 return 0; 2327 } 2328 2329 if (old_tsec->exec_sid) { 2330 new_tsec->sid = old_tsec->exec_sid; 2331 /* Reset exec SID on execve. */ 2332 new_tsec->exec_sid = 0; 2333 2334 /* Fail on NNP or nosuid if not an allowed transition. */ 2335 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2336 if (rc) 2337 return rc; 2338 } else { 2339 /* Check for a default transition on this program. */ 2340 rc = security_transition_sid(old_tsec->sid, 2341 isec->sid, SECCLASS_PROCESS, NULL, 2342 &new_tsec->sid); 2343 if (rc) 2344 return rc; 2345 2346 /* 2347 * Fallback to old SID on NNP or nosuid if not an allowed 2348 * transition. 2349 */ 2350 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2351 if (rc) 2352 new_tsec->sid = old_tsec->sid; 2353 } 2354 2355 ad.type = LSM_AUDIT_DATA_FILE; 2356 ad.u.file = bprm->file; 2357 2358 if (new_tsec->sid == old_tsec->sid) { 2359 rc = avc_has_perm(old_tsec->sid, isec->sid, 2360 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2361 if (rc) 2362 return rc; 2363 } else { 2364 /* Check permissions for the transition. */ 2365 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2366 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2367 if (rc) 2368 return rc; 2369 2370 rc = avc_has_perm(new_tsec->sid, isec->sid, 2371 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2372 if (rc) 2373 return rc; 2374 2375 /* Check for shared state */ 2376 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2377 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2378 SECCLASS_PROCESS, PROCESS__SHARE, 2379 NULL); 2380 if (rc) 2381 return -EPERM; 2382 } 2383 2384 /* Make sure that anyone attempting to ptrace over a task that 2385 * changes its SID has the appropriate permit */ 2386 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2387 u32 ptsid = ptrace_parent_sid(); 2388 if (ptsid != 0) { 2389 rc = avc_has_perm(ptsid, new_tsec->sid, 2390 SECCLASS_PROCESS, 2391 PROCESS__PTRACE, NULL); 2392 if (rc) 2393 return -EPERM; 2394 } 2395 } 2396 2397 /* Clear any possibly unsafe personality bits on exec: */ 2398 bprm->per_clear |= PER_CLEAR_ON_SETID; 2399 2400 /* Enable secure mode for SIDs transitions unless 2401 the noatsecure permission is granted between 2402 the two SIDs, i.e. ahp returns 0. */ 2403 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2404 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2405 NULL); 2406 bprm->secureexec |= !!rc; 2407 } 2408 2409 return 0; 2410 } 2411 2412 static int match_file(const void *p, struct file *file, unsigned fd) 2413 { 2414 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2415 } 2416 2417 /* Derived from fs/exec.c:flush_old_files. */ 2418 static inline void flush_unauthorized_files(const struct cred *cred, 2419 struct files_struct *files) 2420 { 2421 struct file *file, *devnull = NULL; 2422 struct tty_struct *tty; 2423 int drop_tty = 0; 2424 unsigned n; 2425 2426 tty = get_current_tty(); 2427 if (tty) { 2428 spin_lock(&tty->files_lock); 2429 if (!list_empty(&tty->tty_files)) { 2430 struct tty_file_private *file_priv; 2431 2432 /* Revalidate access to controlling tty. 2433 Use file_path_has_perm on the tty path directly 2434 rather than using file_has_perm, as this particular 2435 open file may belong to another process and we are 2436 only interested in the inode-based check here. */ 2437 file_priv = list_first_entry(&tty->tty_files, 2438 struct tty_file_private, list); 2439 file = file_priv->file; 2440 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2441 drop_tty = 1; 2442 } 2443 spin_unlock(&tty->files_lock); 2444 tty_kref_put(tty); 2445 } 2446 /* Reset controlling tty. */ 2447 if (drop_tty) 2448 no_tty(); 2449 2450 /* Revalidate access to inherited open files. */ 2451 n = iterate_fd(files, 0, match_file, cred); 2452 if (!n) /* none found? */ 2453 return; 2454 2455 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2456 if (IS_ERR(devnull)) 2457 devnull = NULL; 2458 /* replace all the matching ones with this */ 2459 do { 2460 replace_fd(n - 1, devnull, 0); 2461 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2462 if (devnull) 2463 fput(devnull); 2464 } 2465 2466 /* 2467 * Prepare a process for imminent new credential changes due to exec 2468 */ 2469 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) 2470 { 2471 struct task_security_struct *new_tsec; 2472 struct rlimit *rlim, *initrlim; 2473 int rc, i; 2474 2475 new_tsec = selinux_cred(bprm->cred); 2476 if (new_tsec->sid == new_tsec->osid) 2477 return; 2478 2479 /* Close files for which the new task SID is not authorized. */ 2480 flush_unauthorized_files(bprm->cred, current->files); 2481 2482 /* Always clear parent death signal on SID transitions. */ 2483 current->pdeath_signal = 0; 2484 2485 /* Check whether the new SID can inherit resource limits from the old 2486 * SID. If not, reset all soft limits to the lower of the current 2487 * task's hard limit and the init task's soft limit. 2488 * 2489 * Note that the setting of hard limits (even to lower them) can be 2490 * controlled by the setrlimit check. The inclusion of the init task's 2491 * soft limit into the computation is to avoid resetting soft limits 2492 * higher than the default soft limit for cases where the default is 2493 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2494 */ 2495 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2496 PROCESS__RLIMITINH, NULL); 2497 if (rc) { 2498 /* protect against do_prlimit() */ 2499 task_lock(current); 2500 for (i = 0; i < RLIM_NLIMITS; i++) { 2501 rlim = current->signal->rlim + i; 2502 initrlim = init_task.signal->rlim + i; 2503 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2504 } 2505 task_unlock(current); 2506 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2507 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2508 } 2509 } 2510 2511 /* 2512 * Clean up the process immediately after the installation of new credentials 2513 * due to exec 2514 */ 2515 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) 2516 { 2517 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2518 u32 osid, sid; 2519 int rc; 2520 2521 osid = tsec->osid; 2522 sid = tsec->sid; 2523 2524 if (sid == osid) 2525 return; 2526 2527 /* Check whether the new SID can inherit signal state from the old SID. 2528 * If not, clear itimers to avoid subsequent signal generation and 2529 * flush and unblock signals. 2530 * 2531 * This must occur _after_ the task SID has been updated so that any 2532 * kill done after the flush will be checked against the new SID. 2533 */ 2534 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2535 if (rc) { 2536 clear_itimer(); 2537 2538 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); 2539 if (!fatal_signal_pending(current)) { 2540 flush_sigqueue(¤t->pending); 2541 flush_sigqueue(¤t->signal->shared_pending); 2542 flush_signal_handlers(current, 1); 2543 sigemptyset(¤t->blocked); 2544 recalc_sigpending(); 2545 } 2546 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); 2547 } 2548 2549 /* Wake up the parent if it is waiting so that it can recheck 2550 * wait permission to the new task SID. */ 2551 read_lock(&tasklist_lock); 2552 __wake_up_parent(current, unrcu_pointer(current->real_parent)); 2553 read_unlock(&tasklist_lock); 2554 } 2555 2556 /* superblock security operations */ 2557 2558 static int selinux_sb_alloc_security(struct super_block *sb) 2559 { 2560 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2561 2562 mutex_init(&sbsec->lock); 2563 INIT_LIST_HEAD(&sbsec->isec_head); 2564 spin_lock_init(&sbsec->isec_lock); 2565 sbsec->sid = SECINITSID_UNLABELED; 2566 sbsec->def_sid = SECINITSID_FILE; 2567 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2568 2569 return 0; 2570 } 2571 2572 static inline int opt_len(const char *s) 2573 { 2574 bool open_quote = false; 2575 int len; 2576 char c; 2577 2578 for (len = 0; (c = s[len]) != '\0'; len++) { 2579 if (c == '"') 2580 open_quote = !open_quote; 2581 if (c == ',' && !open_quote) 2582 break; 2583 } 2584 return len; 2585 } 2586 2587 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2588 { 2589 char *from = options; 2590 char *to = options; 2591 bool first = true; 2592 int rc; 2593 2594 while (1) { 2595 int len = opt_len(from); 2596 int token; 2597 char *arg = NULL; 2598 2599 token = match_opt_prefix(from, len, &arg); 2600 2601 if (token != Opt_error) { 2602 char *p, *q; 2603 2604 /* strip quotes */ 2605 if (arg) { 2606 for (p = q = arg; p < from + len; p++) { 2607 char c = *p; 2608 if (c != '"') 2609 *q++ = c; 2610 } 2611 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2612 if (!arg) { 2613 rc = -ENOMEM; 2614 goto free_opt; 2615 } 2616 } 2617 rc = selinux_add_opt(token, arg, mnt_opts); 2618 kfree(arg); 2619 arg = NULL; 2620 if (unlikely(rc)) { 2621 goto free_opt; 2622 } 2623 } else { 2624 if (!first) { // copy with preceding comma 2625 from--; 2626 len++; 2627 } 2628 if (to != from) 2629 memmove(to, from, len); 2630 to += len; 2631 first = false; 2632 } 2633 if (!from[len]) 2634 break; 2635 from += len + 1; 2636 } 2637 *to = '\0'; 2638 return 0; 2639 2640 free_opt: 2641 if (*mnt_opts) { 2642 selinux_free_mnt_opts(*mnt_opts); 2643 *mnt_opts = NULL; 2644 } 2645 return rc; 2646 } 2647 2648 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2649 { 2650 struct selinux_mnt_opts *opts = mnt_opts; 2651 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2652 2653 /* 2654 * Superblock not initialized (i.e. no options) - reject if any 2655 * options specified, otherwise accept. 2656 */ 2657 if (!(sbsec->flags & SE_SBINITIALIZED)) 2658 return opts ? 1 : 0; 2659 2660 /* 2661 * Superblock initialized and no options specified - reject if 2662 * superblock has any options set, otherwise accept. 2663 */ 2664 if (!opts) 2665 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2666 2667 if (opts->fscontext_sid) { 2668 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2669 opts->fscontext_sid)) 2670 return 1; 2671 } 2672 if (opts->context_sid) { 2673 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2674 opts->context_sid)) 2675 return 1; 2676 } 2677 if (opts->rootcontext_sid) { 2678 struct inode_security_struct *root_isec; 2679 2680 root_isec = backing_inode_security(sb->s_root); 2681 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2682 opts->rootcontext_sid)) 2683 return 1; 2684 } 2685 if (opts->defcontext_sid) { 2686 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2687 opts->defcontext_sid)) 2688 return 1; 2689 } 2690 return 0; 2691 } 2692 2693 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2694 { 2695 struct selinux_mnt_opts *opts = mnt_opts; 2696 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2697 2698 if (!(sbsec->flags & SE_SBINITIALIZED)) 2699 return 0; 2700 2701 if (!opts) 2702 return 0; 2703 2704 if (opts->fscontext_sid) { 2705 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2706 opts->fscontext_sid)) 2707 goto out_bad_option; 2708 } 2709 if (opts->context_sid) { 2710 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2711 opts->context_sid)) 2712 goto out_bad_option; 2713 } 2714 if (opts->rootcontext_sid) { 2715 struct inode_security_struct *root_isec; 2716 root_isec = backing_inode_security(sb->s_root); 2717 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2718 opts->rootcontext_sid)) 2719 goto out_bad_option; 2720 } 2721 if (opts->defcontext_sid) { 2722 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2723 opts->defcontext_sid)) 2724 goto out_bad_option; 2725 } 2726 return 0; 2727 2728 out_bad_option: 2729 pr_warn("SELinux: unable to change security options " 2730 "during remount (dev %s, type=%s)\n", sb->s_id, 2731 sb->s_type->name); 2732 return -EINVAL; 2733 } 2734 2735 static int selinux_sb_kern_mount(const struct super_block *sb) 2736 { 2737 const struct cred *cred = current_cred(); 2738 struct common_audit_data ad; 2739 2740 ad.type = LSM_AUDIT_DATA_DENTRY; 2741 ad.u.dentry = sb->s_root; 2742 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2743 } 2744 2745 static int selinux_sb_statfs(struct dentry *dentry) 2746 { 2747 const struct cred *cred = current_cred(); 2748 struct common_audit_data ad; 2749 2750 ad.type = LSM_AUDIT_DATA_DENTRY; 2751 ad.u.dentry = dentry->d_sb->s_root; 2752 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2753 } 2754 2755 static int selinux_mount(const char *dev_name, 2756 const struct path *path, 2757 const char *type, 2758 unsigned long flags, 2759 void *data) 2760 { 2761 const struct cred *cred = current_cred(); 2762 2763 if (flags & MS_REMOUNT) 2764 return superblock_has_perm(cred, path->dentry->d_sb, 2765 FILESYSTEM__REMOUNT, NULL); 2766 else 2767 return path_has_perm(cred, path, FILE__MOUNTON); 2768 } 2769 2770 static int selinux_move_mount(const struct path *from_path, 2771 const struct path *to_path) 2772 { 2773 const struct cred *cred = current_cred(); 2774 2775 return path_has_perm(cred, to_path, FILE__MOUNTON); 2776 } 2777 2778 static int selinux_umount(struct vfsmount *mnt, int flags) 2779 { 2780 const struct cred *cred = current_cred(); 2781 2782 return superblock_has_perm(cred, mnt->mnt_sb, 2783 FILESYSTEM__UNMOUNT, NULL); 2784 } 2785 2786 static int selinux_fs_context_submount(struct fs_context *fc, 2787 struct super_block *reference) 2788 { 2789 const struct superblock_security_struct *sbsec = selinux_superblock(reference); 2790 struct selinux_mnt_opts *opts; 2791 2792 /* 2793 * Ensure that fc->security remains NULL when no options are set 2794 * as expected by selinux_set_mnt_opts(). 2795 */ 2796 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) 2797 return 0; 2798 2799 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 2800 if (!opts) 2801 return -ENOMEM; 2802 2803 if (sbsec->flags & FSCONTEXT_MNT) 2804 opts->fscontext_sid = sbsec->sid; 2805 if (sbsec->flags & CONTEXT_MNT) 2806 opts->context_sid = sbsec->mntpoint_sid; 2807 if (sbsec->flags & DEFCONTEXT_MNT) 2808 opts->defcontext_sid = sbsec->def_sid; 2809 fc->security = opts; 2810 return 0; 2811 } 2812 2813 static int selinux_fs_context_dup(struct fs_context *fc, 2814 struct fs_context *src_fc) 2815 { 2816 const struct selinux_mnt_opts *src = src_fc->security; 2817 2818 if (!src) 2819 return 0; 2820 2821 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); 2822 return fc->security ? 0 : -ENOMEM; 2823 } 2824 2825 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2826 fsparam_string(CONTEXT_STR, Opt_context), 2827 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2828 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2829 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2830 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2831 {} 2832 }; 2833 2834 static int selinux_fs_context_parse_param(struct fs_context *fc, 2835 struct fs_parameter *param) 2836 { 2837 struct fs_parse_result result; 2838 int opt; 2839 2840 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2841 if (opt < 0) 2842 return opt; 2843 2844 return selinux_add_opt(opt, param->string, &fc->security); 2845 } 2846 2847 /* inode security operations */ 2848 2849 static int selinux_inode_alloc_security(struct inode *inode) 2850 { 2851 struct inode_security_struct *isec = selinux_inode(inode); 2852 u32 sid = current_sid(); 2853 2854 spin_lock_init(&isec->lock); 2855 INIT_LIST_HEAD(&isec->list); 2856 isec->inode = inode; 2857 isec->sid = SECINITSID_UNLABELED; 2858 isec->sclass = SECCLASS_FILE; 2859 isec->task_sid = sid; 2860 isec->initialized = LABEL_INVALID; 2861 2862 return 0; 2863 } 2864 2865 static void selinux_inode_free_security(struct inode *inode) 2866 { 2867 inode_free_security(inode); 2868 } 2869 2870 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2871 const struct qstr *name, 2872 const char **xattr_name, 2873 struct lsm_context *cp) 2874 { 2875 u32 newsid; 2876 int rc; 2877 2878 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2879 d_inode(dentry->d_parent), name, 2880 inode_mode_to_security_class(mode), 2881 &newsid); 2882 if (rc) 2883 return rc; 2884 2885 if (xattr_name) 2886 *xattr_name = XATTR_NAME_SELINUX; 2887 2888 cp->id = LSM_ID_SELINUX; 2889 return security_sid_to_context(newsid, &cp->context, &cp->len); 2890 } 2891 2892 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2893 struct qstr *name, 2894 const struct cred *old, 2895 struct cred *new) 2896 { 2897 u32 newsid; 2898 int rc; 2899 struct task_security_struct *tsec; 2900 2901 rc = selinux_determine_inode_label(selinux_cred(old), 2902 d_inode(dentry->d_parent), name, 2903 inode_mode_to_security_class(mode), 2904 &newsid); 2905 if (rc) 2906 return rc; 2907 2908 tsec = selinux_cred(new); 2909 tsec->create_sid = newsid; 2910 return 0; 2911 } 2912 2913 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2914 const struct qstr *qstr, 2915 struct xattr *xattrs, int *xattr_count) 2916 { 2917 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2918 struct superblock_security_struct *sbsec; 2919 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); 2920 u32 newsid, clen; 2921 u16 newsclass; 2922 int rc; 2923 char *context; 2924 2925 sbsec = selinux_superblock(dir->i_sb); 2926 2927 newsid = tsec->create_sid; 2928 newsclass = inode_mode_to_security_class(inode->i_mode); 2929 rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid); 2930 if (rc) 2931 return rc; 2932 2933 /* Possibly defer initialization to selinux_complete_init. */ 2934 if (sbsec->flags & SE_SBINITIALIZED) { 2935 struct inode_security_struct *isec = selinux_inode(inode); 2936 isec->sclass = newsclass; 2937 isec->sid = newsid; 2938 isec->initialized = LABEL_INITIALIZED; 2939 } 2940 2941 if (!selinux_initialized() || 2942 !(sbsec->flags & SBLABEL_MNT)) 2943 return -EOPNOTSUPP; 2944 2945 if (xattr) { 2946 rc = security_sid_to_context_force(newsid, 2947 &context, &clen); 2948 if (rc) 2949 return rc; 2950 xattr->value = context; 2951 xattr->value_len = clen; 2952 xattr->name = XATTR_SELINUX_SUFFIX; 2953 } 2954 2955 return 0; 2956 } 2957 2958 static int selinux_inode_init_security_anon(struct inode *inode, 2959 const struct qstr *name, 2960 const struct inode *context_inode) 2961 { 2962 u32 sid = current_sid(); 2963 struct common_audit_data ad; 2964 struct inode_security_struct *isec; 2965 int rc; 2966 2967 if (unlikely(!selinux_initialized())) 2968 return 0; 2969 2970 isec = selinux_inode(inode); 2971 2972 /* 2973 * We only get here once per ephemeral inode. The inode has 2974 * been initialized via inode_alloc_security but is otherwise 2975 * untouched. 2976 */ 2977 2978 if (context_inode) { 2979 struct inode_security_struct *context_isec = 2980 selinux_inode(context_inode); 2981 if (context_isec->initialized != LABEL_INITIALIZED) { 2982 pr_err("SELinux: context_inode is not initialized\n"); 2983 return -EACCES; 2984 } 2985 2986 isec->sclass = context_isec->sclass; 2987 isec->sid = context_isec->sid; 2988 } else { 2989 isec->sclass = SECCLASS_ANON_INODE; 2990 rc = security_transition_sid( 2991 sid, sid, 2992 isec->sclass, name, &isec->sid); 2993 if (rc) 2994 return rc; 2995 } 2996 2997 isec->initialized = LABEL_INITIALIZED; 2998 /* 2999 * Now that we've initialized security, check whether we're 3000 * allowed to actually create this type of anonymous inode. 3001 */ 3002 3003 ad.type = LSM_AUDIT_DATA_ANONINODE; 3004 ad.u.anonclass = name ? (const char *)name->name : "?"; 3005 3006 return avc_has_perm(sid, 3007 isec->sid, 3008 isec->sclass, 3009 FILE__CREATE, 3010 &ad); 3011 } 3012 3013 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3014 { 3015 return may_create(dir, dentry, SECCLASS_FILE); 3016 } 3017 3018 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3019 { 3020 return may_link(dir, old_dentry, MAY_LINK); 3021 } 3022 3023 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3024 { 3025 return may_link(dir, dentry, MAY_UNLINK); 3026 } 3027 3028 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3029 { 3030 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3031 } 3032 3033 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3034 { 3035 return may_create(dir, dentry, SECCLASS_DIR); 3036 } 3037 3038 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3039 { 3040 return may_link(dir, dentry, MAY_RMDIR); 3041 } 3042 3043 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3044 { 3045 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3046 } 3047 3048 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3049 struct inode *new_inode, struct dentry *new_dentry) 3050 { 3051 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3052 } 3053 3054 static int selinux_inode_readlink(struct dentry *dentry) 3055 { 3056 const struct cred *cred = current_cred(); 3057 3058 return dentry_has_perm(cred, dentry, FILE__READ); 3059 } 3060 3061 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3062 bool rcu) 3063 { 3064 struct common_audit_data ad; 3065 struct inode_security_struct *isec; 3066 u32 sid = current_sid(); 3067 3068 ad.type = LSM_AUDIT_DATA_DENTRY; 3069 ad.u.dentry = dentry; 3070 isec = inode_security_rcu(inode, rcu); 3071 if (IS_ERR(isec)) 3072 return PTR_ERR(isec); 3073 3074 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); 3075 } 3076 3077 static noinline int audit_inode_permission(struct inode *inode, 3078 u32 perms, u32 audited, u32 denied, 3079 int result) 3080 { 3081 struct common_audit_data ad; 3082 struct inode_security_struct *isec = selinux_inode(inode); 3083 3084 ad.type = LSM_AUDIT_DATA_INODE; 3085 ad.u.inode = inode; 3086 3087 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3088 audited, denied, result, &ad); 3089 } 3090 3091 static int selinux_inode_permission(struct inode *inode, int mask) 3092 { 3093 u32 perms; 3094 bool from_access; 3095 bool no_block = mask & MAY_NOT_BLOCK; 3096 struct inode_security_struct *isec; 3097 u32 sid = current_sid(); 3098 struct av_decision avd; 3099 int rc, rc2; 3100 u32 audited, denied; 3101 3102 from_access = mask & MAY_ACCESS; 3103 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3104 3105 /* No permission to check. Existence test. */ 3106 if (!mask) 3107 return 0; 3108 3109 if (unlikely(IS_PRIVATE(inode))) 3110 return 0; 3111 3112 perms = file_mask_to_av(inode->i_mode, mask); 3113 3114 isec = inode_security_rcu(inode, no_block); 3115 if (IS_ERR(isec)) 3116 return PTR_ERR(isec); 3117 3118 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, 3119 &avd); 3120 audited = avc_audit_required(perms, &avd, rc, 3121 from_access ? FILE__AUDIT_ACCESS : 0, 3122 &denied); 3123 if (likely(!audited)) 3124 return rc; 3125 3126 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3127 if (rc2) 3128 return rc2; 3129 return rc; 3130 } 3131 3132 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 3133 struct iattr *iattr) 3134 { 3135 const struct cred *cred = current_cred(); 3136 struct inode *inode = d_backing_inode(dentry); 3137 unsigned int ia_valid = iattr->ia_valid; 3138 u32 av = FILE__WRITE; 3139 3140 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3141 if (ia_valid & ATTR_FORCE) { 3142 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3143 ATTR_FORCE); 3144 if (!ia_valid) 3145 return 0; 3146 } 3147 3148 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3149 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3150 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3151 3152 if (selinux_policycap_openperm() && 3153 inode->i_sb->s_magic != SOCKFS_MAGIC && 3154 (ia_valid & ATTR_SIZE) && 3155 !(ia_valid & ATTR_FILE)) 3156 av |= FILE__OPEN; 3157 3158 return dentry_has_perm(cred, dentry, av); 3159 } 3160 3161 static int selinux_inode_getattr(const struct path *path) 3162 { 3163 return path_has_perm(current_cred(), path, FILE__GETATTR); 3164 } 3165 3166 static bool has_cap_mac_admin(bool audit) 3167 { 3168 const struct cred *cred = current_cred(); 3169 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3170 3171 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3172 return false; 3173 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3174 return false; 3175 return true; 3176 } 3177 3178 /** 3179 * selinux_inode_xattr_skipcap - Skip the xattr capability checks? 3180 * @name: name of the xattr 3181 * 3182 * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs 3183 * named @name; the LSM layer should avoid enforcing any traditional 3184 * capability based access controls on this xattr. Returns 0 to indicate that 3185 * SELinux does not "own" the access control rights to xattrs named @name and is 3186 * deferring to the LSM layer for further access controls, including capability 3187 * based controls. 3188 */ 3189 static int selinux_inode_xattr_skipcap(const char *name) 3190 { 3191 /* require capability check if not a selinux xattr */ 3192 return !strcmp(name, XATTR_NAME_SELINUX); 3193 } 3194 3195 static int selinux_inode_setxattr(struct mnt_idmap *idmap, 3196 struct dentry *dentry, const char *name, 3197 const void *value, size_t size, int flags) 3198 { 3199 struct inode *inode = d_backing_inode(dentry); 3200 struct inode_security_struct *isec; 3201 struct superblock_security_struct *sbsec; 3202 struct common_audit_data ad; 3203 u32 newsid, sid = current_sid(); 3204 int rc = 0; 3205 3206 /* if not a selinux xattr, only check the ordinary setattr perm */ 3207 if (strcmp(name, XATTR_NAME_SELINUX)) 3208 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3209 3210 if (!selinux_initialized()) 3211 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); 3212 3213 sbsec = selinux_superblock(inode->i_sb); 3214 if (!(sbsec->flags & SBLABEL_MNT)) 3215 return -EOPNOTSUPP; 3216 3217 if (!inode_owner_or_capable(idmap, inode)) 3218 return -EPERM; 3219 3220 ad.type = LSM_AUDIT_DATA_DENTRY; 3221 ad.u.dentry = dentry; 3222 3223 isec = backing_inode_security(dentry); 3224 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3225 FILE__RELABELFROM, &ad); 3226 if (rc) 3227 return rc; 3228 3229 rc = security_context_to_sid(value, size, &newsid, 3230 GFP_KERNEL); 3231 if (rc == -EINVAL) { 3232 if (!has_cap_mac_admin(true)) { 3233 struct audit_buffer *ab; 3234 size_t audit_size; 3235 3236 /* We strip a nul only if it is at the end, otherwise the 3237 * context contains a nul and we should audit that */ 3238 if (value) { 3239 const char *str = value; 3240 3241 if (str[size - 1] == '\0') 3242 audit_size = size - 1; 3243 else 3244 audit_size = size; 3245 } else { 3246 audit_size = 0; 3247 } 3248 ab = audit_log_start(audit_context(), 3249 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3250 if (!ab) 3251 return rc; 3252 audit_log_format(ab, "op=setxattr invalid_context="); 3253 audit_log_n_untrustedstring(ab, value, audit_size); 3254 audit_log_end(ab); 3255 3256 return rc; 3257 } 3258 rc = security_context_to_sid_force(value, 3259 size, &newsid); 3260 } 3261 if (rc) 3262 return rc; 3263 3264 rc = avc_has_perm(sid, newsid, isec->sclass, 3265 FILE__RELABELTO, &ad); 3266 if (rc) 3267 return rc; 3268 3269 rc = security_validate_transition(isec->sid, newsid, 3270 sid, isec->sclass); 3271 if (rc) 3272 return rc; 3273 3274 return avc_has_perm(newsid, 3275 sbsec->sid, 3276 SECCLASS_FILESYSTEM, 3277 FILESYSTEM__ASSOCIATE, 3278 &ad); 3279 } 3280 3281 static int selinux_inode_set_acl(struct mnt_idmap *idmap, 3282 struct dentry *dentry, const char *acl_name, 3283 struct posix_acl *kacl) 3284 { 3285 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3286 } 3287 3288 static int selinux_inode_get_acl(struct mnt_idmap *idmap, 3289 struct dentry *dentry, const char *acl_name) 3290 { 3291 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); 3292 } 3293 3294 static int selinux_inode_remove_acl(struct mnt_idmap *idmap, 3295 struct dentry *dentry, const char *acl_name) 3296 { 3297 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3298 } 3299 3300 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3301 const void *value, size_t size, 3302 int flags) 3303 { 3304 struct inode *inode = d_backing_inode(dentry); 3305 struct inode_security_struct *isec; 3306 u32 newsid; 3307 int rc; 3308 3309 if (strcmp(name, XATTR_NAME_SELINUX)) { 3310 /* Not an attribute we recognize, so nothing to do. */ 3311 return; 3312 } 3313 3314 if (!selinux_initialized()) { 3315 /* If we haven't even been initialized, then we can't validate 3316 * against a policy, so leave the label as invalid. It may 3317 * resolve to a valid label on the next revalidation try if 3318 * we've since initialized. 3319 */ 3320 return; 3321 } 3322 3323 rc = security_context_to_sid_force(value, size, 3324 &newsid); 3325 if (rc) { 3326 pr_err("SELinux: unable to map context to SID" 3327 "for (%s, %lu), rc=%d\n", 3328 inode->i_sb->s_id, inode->i_ino, -rc); 3329 return; 3330 } 3331 3332 isec = backing_inode_security(dentry); 3333 spin_lock(&isec->lock); 3334 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3335 isec->sid = newsid; 3336 isec->initialized = LABEL_INITIALIZED; 3337 spin_unlock(&isec->lock); 3338 } 3339 3340 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3341 { 3342 const struct cred *cred = current_cred(); 3343 3344 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3345 } 3346 3347 static int selinux_inode_listxattr(struct dentry *dentry) 3348 { 3349 const struct cred *cred = current_cred(); 3350 3351 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3352 } 3353 3354 static int selinux_inode_removexattr(struct mnt_idmap *idmap, 3355 struct dentry *dentry, const char *name) 3356 { 3357 /* if not a selinux xattr, only check the ordinary setattr perm */ 3358 if (strcmp(name, XATTR_NAME_SELINUX)) 3359 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3360 3361 if (!selinux_initialized()) 3362 return 0; 3363 3364 /* No one is allowed to remove a SELinux security label. 3365 You can change the label, but all data must be labeled. */ 3366 return -EACCES; 3367 } 3368 3369 static int selinux_path_notify(const struct path *path, u64 mask, 3370 unsigned int obj_type) 3371 { 3372 int ret; 3373 u32 perm; 3374 3375 struct common_audit_data ad; 3376 3377 ad.type = LSM_AUDIT_DATA_PATH; 3378 ad.u.path = *path; 3379 3380 /* 3381 * Set permission needed based on the type of mark being set. 3382 * Performs an additional check for sb watches. 3383 */ 3384 switch (obj_type) { 3385 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3386 perm = FILE__WATCH_MOUNT; 3387 break; 3388 case FSNOTIFY_OBJ_TYPE_SB: 3389 perm = FILE__WATCH_SB; 3390 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3391 FILESYSTEM__WATCH, &ad); 3392 if (ret) 3393 return ret; 3394 break; 3395 case FSNOTIFY_OBJ_TYPE_INODE: 3396 perm = FILE__WATCH; 3397 break; 3398 case FSNOTIFY_OBJ_TYPE_MNTNS: 3399 perm = FILE__WATCH_MOUNTNS; 3400 break; 3401 default: 3402 return -EINVAL; 3403 } 3404 3405 /* blocking watches require the file:watch_with_perm permission */ 3406 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3407 perm |= FILE__WATCH_WITH_PERM; 3408 3409 /* watches on read-like events need the file:watch_reads permission */ 3410 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_PRE_ACCESS | 3411 FS_CLOSE_NOWRITE)) 3412 perm |= FILE__WATCH_READS; 3413 3414 return path_has_perm(current_cred(), path, perm); 3415 } 3416 3417 /* 3418 * Copy the inode security context value to the user. 3419 * 3420 * Permission check is handled by selinux_inode_getxattr hook. 3421 */ 3422 static int selinux_inode_getsecurity(struct mnt_idmap *idmap, 3423 struct inode *inode, const char *name, 3424 void **buffer, bool alloc) 3425 { 3426 u32 size; 3427 int error; 3428 char *context = NULL; 3429 struct inode_security_struct *isec; 3430 3431 /* 3432 * If we're not initialized yet, then we can't validate contexts, so 3433 * just let vfs_getxattr fall back to using the on-disk xattr. 3434 */ 3435 if (!selinux_initialized() || 3436 strcmp(name, XATTR_SELINUX_SUFFIX)) 3437 return -EOPNOTSUPP; 3438 3439 /* 3440 * If the caller has CAP_MAC_ADMIN, then get the raw context 3441 * value even if it is not defined by current policy; otherwise, 3442 * use the in-core value under current policy. 3443 * Use the non-auditing forms of the permission checks since 3444 * getxattr may be called by unprivileged processes commonly 3445 * and lack of permission just means that we fall back to the 3446 * in-core context value, not a denial. 3447 */ 3448 isec = inode_security(inode); 3449 if (has_cap_mac_admin(false)) 3450 error = security_sid_to_context_force(isec->sid, &context, 3451 &size); 3452 else 3453 error = security_sid_to_context(isec->sid, 3454 &context, &size); 3455 if (error) 3456 return error; 3457 error = size; 3458 if (alloc) { 3459 *buffer = context; 3460 goto out_nofree; 3461 } 3462 kfree(context); 3463 out_nofree: 3464 return error; 3465 } 3466 3467 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3468 const void *value, size_t size, int flags) 3469 { 3470 struct inode_security_struct *isec = inode_security_novalidate(inode); 3471 struct superblock_security_struct *sbsec; 3472 u32 newsid; 3473 int rc; 3474 3475 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3476 return -EOPNOTSUPP; 3477 3478 sbsec = selinux_superblock(inode->i_sb); 3479 if (!(sbsec->flags & SBLABEL_MNT)) 3480 return -EOPNOTSUPP; 3481 3482 if (!value || !size) 3483 return -EACCES; 3484 3485 rc = security_context_to_sid(value, size, &newsid, 3486 GFP_KERNEL); 3487 if (rc) 3488 return rc; 3489 3490 spin_lock(&isec->lock); 3491 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3492 isec->sid = newsid; 3493 isec->initialized = LABEL_INITIALIZED; 3494 spin_unlock(&isec->lock); 3495 return 0; 3496 } 3497 3498 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3499 { 3500 const int len = sizeof(XATTR_NAME_SELINUX); 3501 3502 if (!selinux_initialized()) 3503 return 0; 3504 3505 if (buffer && len <= buffer_size) 3506 memcpy(buffer, XATTR_NAME_SELINUX, len); 3507 return len; 3508 } 3509 3510 static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop) 3511 { 3512 struct inode_security_struct *isec = inode_security_novalidate(inode); 3513 3514 prop->selinux.secid = isec->sid; 3515 } 3516 3517 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3518 { 3519 struct lsm_prop prop; 3520 struct task_security_struct *tsec; 3521 struct cred *new_creds = *new; 3522 3523 if (new_creds == NULL) { 3524 new_creds = prepare_creds(); 3525 if (!new_creds) 3526 return -ENOMEM; 3527 } 3528 3529 tsec = selinux_cred(new_creds); 3530 /* Get label from overlay inode and set it in create_sid */ 3531 selinux_inode_getlsmprop(d_inode(src), &prop); 3532 tsec->create_sid = prop.selinux.secid; 3533 *new = new_creds; 3534 return 0; 3535 } 3536 3537 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name) 3538 { 3539 /* The copy_up hook above sets the initial context on an inode, but we 3540 * don't then want to overwrite it by blindly copying all the lower 3541 * xattrs up. Instead, filter out SELinux-related xattrs following 3542 * policy load. 3543 */ 3544 if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX)) 3545 return -ECANCELED; /* Discard */ 3546 /* 3547 * Any other attribute apart from SELINUX is not claimed, supported 3548 * by selinux. 3549 */ 3550 return -EOPNOTSUPP; 3551 } 3552 3553 /* kernfs node operations */ 3554 3555 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3556 struct kernfs_node *kn) 3557 { 3558 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3559 u32 parent_sid, newsid, clen; 3560 int rc; 3561 char *context; 3562 3563 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3564 if (rc == -ENODATA) 3565 return 0; 3566 else if (rc < 0) 3567 return rc; 3568 3569 clen = (u32)rc; 3570 context = kmalloc(clen, GFP_KERNEL); 3571 if (!context) 3572 return -ENOMEM; 3573 3574 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3575 if (rc < 0) { 3576 kfree(context); 3577 return rc; 3578 } 3579 3580 rc = security_context_to_sid(context, clen, &parent_sid, 3581 GFP_KERNEL); 3582 kfree(context); 3583 if (rc) 3584 return rc; 3585 3586 if (tsec->create_sid) { 3587 newsid = tsec->create_sid; 3588 } else { 3589 u16 secclass = inode_mode_to_security_class(kn->mode); 3590 struct qstr q; 3591 3592 q.name = kn->name; 3593 q.hash_len = hashlen_string(kn_dir, kn->name); 3594 3595 rc = security_transition_sid(tsec->sid, 3596 parent_sid, secclass, &q, 3597 &newsid); 3598 if (rc) 3599 return rc; 3600 } 3601 3602 rc = security_sid_to_context_force(newsid, 3603 &context, &clen); 3604 if (rc) 3605 return rc; 3606 3607 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3608 XATTR_CREATE); 3609 kfree(context); 3610 return rc; 3611 } 3612 3613 3614 /* file security operations */ 3615 3616 static int selinux_revalidate_file_permission(struct file *file, int mask) 3617 { 3618 const struct cred *cred = current_cred(); 3619 struct inode *inode = file_inode(file); 3620 3621 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3622 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3623 mask |= MAY_APPEND; 3624 3625 return file_has_perm(cred, file, 3626 file_mask_to_av(inode->i_mode, mask)); 3627 } 3628 3629 static int selinux_file_permission(struct file *file, int mask) 3630 { 3631 struct inode *inode = file_inode(file); 3632 struct file_security_struct *fsec = selinux_file(file); 3633 struct inode_security_struct *isec; 3634 u32 sid = current_sid(); 3635 3636 if (!mask) 3637 /* No permission to check. Existence test. */ 3638 return 0; 3639 3640 isec = inode_security(inode); 3641 if (sid == fsec->sid && fsec->isid == isec->sid && 3642 fsec->pseqno == avc_policy_seqno()) 3643 /* No change since file_open check. */ 3644 return 0; 3645 3646 return selinux_revalidate_file_permission(file, mask); 3647 } 3648 3649 static int selinux_file_alloc_security(struct file *file) 3650 { 3651 struct file_security_struct *fsec = selinux_file(file); 3652 u32 sid = current_sid(); 3653 3654 fsec->sid = sid; 3655 fsec->fown_sid = sid; 3656 3657 return 0; 3658 } 3659 3660 /* 3661 * Check whether a task has the ioctl permission and cmd 3662 * operation to an inode. 3663 */ 3664 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3665 u32 requested, u16 cmd) 3666 { 3667 struct common_audit_data ad; 3668 struct file_security_struct *fsec = selinux_file(file); 3669 struct inode *inode = file_inode(file); 3670 struct inode_security_struct *isec; 3671 struct lsm_ioctlop_audit ioctl; 3672 u32 ssid = cred_sid(cred); 3673 int rc; 3674 u8 driver = cmd >> 8; 3675 u8 xperm = cmd & 0xff; 3676 3677 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3678 ad.u.op = &ioctl; 3679 ad.u.op->cmd = cmd; 3680 ad.u.op->path = file->f_path; 3681 3682 if (ssid != fsec->sid) { 3683 rc = avc_has_perm(ssid, fsec->sid, 3684 SECCLASS_FD, 3685 FD__USE, 3686 &ad); 3687 if (rc) 3688 goto out; 3689 } 3690 3691 if (unlikely(IS_PRIVATE(inode))) 3692 return 0; 3693 3694 isec = inode_security(inode); 3695 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, requested, 3696 driver, AVC_EXT_IOCTL, xperm, &ad); 3697 out: 3698 return rc; 3699 } 3700 3701 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3702 unsigned long arg) 3703 { 3704 const struct cred *cred = current_cred(); 3705 int error = 0; 3706 3707 switch (cmd) { 3708 case FIONREAD: 3709 case FIBMAP: 3710 case FIGETBSZ: 3711 case FS_IOC_GETFLAGS: 3712 case FS_IOC_GETVERSION: 3713 error = file_has_perm(cred, file, FILE__GETATTR); 3714 break; 3715 3716 case FS_IOC_SETFLAGS: 3717 case FS_IOC_SETVERSION: 3718 error = file_has_perm(cred, file, FILE__SETATTR); 3719 break; 3720 3721 /* sys_ioctl() checks */ 3722 case FIONBIO: 3723 case FIOASYNC: 3724 error = file_has_perm(cred, file, 0); 3725 break; 3726 3727 case KDSKBENT: 3728 case KDSKBSENT: 3729 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3730 CAP_OPT_NONE, true); 3731 break; 3732 3733 case FIOCLEX: 3734 case FIONCLEX: 3735 if (!selinux_policycap_ioctl_skip_cloexec()) 3736 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3737 break; 3738 3739 /* default case assumes that the command will go 3740 * to the file's ioctl() function. 3741 */ 3742 default: 3743 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3744 } 3745 return error; 3746 } 3747 3748 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd, 3749 unsigned long arg) 3750 { 3751 /* 3752 * If we are in a 64-bit kernel running 32-bit userspace, we need to 3753 * make sure we don't compare 32-bit flags to 64-bit flags. 3754 */ 3755 switch (cmd) { 3756 case FS_IOC32_GETFLAGS: 3757 cmd = FS_IOC_GETFLAGS; 3758 break; 3759 case FS_IOC32_SETFLAGS: 3760 cmd = FS_IOC_SETFLAGS; 3761 break; 3762 case FS_IOC32_GETVERSION: 3763 cmd = FS_IOC_GETVERSION; 3764 break; 3765 case FS_IOC32_SETVERSION: 3766 cmd = FS_IOC_SETVERSION; 3767 break; 3768 default: 3769 break; 3770 } 3771 3772 return selinux_file_ioctl(file, cmd, arg); 3773 } 3774 3775 static int default_noexec __ro_after_init; 3776 3777 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3778 { 3779 const struct cred *cred = current_cred(); 3780 u32 sid = cred_sid(cred); 3781 int rc = 0; 3782 3783 if (default_noexec && 3784 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3785 (!shared && (prot & PROT_WRITE)))) { 3786 /* 3787 * We are making executable an anonymous mapping or a 3788 * private file mapping that will also be writable. 3789 * This has an additional check. 3790 */ 3791 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3792 PROCESS__EXECMEM, NULL); 3793 if (rc) 3794 goto error; 3795 } 3796 3797 if (file) { 3798 /* read access is always possible with a mapping */ 3799 u32 av = FILE__READ; 3800 3801 /* write access only matters if the mapping is shared */ 3802 if (shared && (prot & PROT_WRITE)) 3803 av |= FILE__WRITE; 3804 3805 if (prot & PROT_EXEC) 3806 av |= FILE__EXECUTE; 3807 3808 return file_has_perm(cred, file, av); 3809 } 3810 3811 error: 3812 return rc; 3813 } 3814 3815 static int selinux_mmap_addr(unsigned long addr) 3816 { 3817 int rc = 0; 3818 3819 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3820 u32 sid = current_sid(); 3821 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3822 MEMPROTECT__MMAP_ZERO, NULL); 3823 } 3824 3825 return rc; 3826 } 3827 3828 static int selinux_mmap_file(struct file *file, 3829 unsigned long reqprot __always_unused, 3830 unsigned long prot, unsigned long flags) 3831 { 3832 struct common_audit_data ad; 3833 int rc; 3834 3835 if (file) { 3836 ad.type = LSM_AUDIT_DATA_FILE; 3837 ad.u.file = file; 3838 rc = inode_has_perm(current_cred(), file_inode(file), 3839 FILE__MAP, &ad); 3840 if (rc) 3841 return rc; 3842 } 3843 3844 return file_map_prot_check(file, prot, 3845 (flags & MAP_TYPE) == MAP_SHARED); 3846 } 3847 3848 static int selinux_file_mprotect(struct vm_area_struct *vma, 3849 unsigned long reqprot __always_unused, 3850 unsigned long prot) 3851 { 3852 const struct cred *cred = current_cred(); 3853 u32 sid = cred_sid(cred); 3854 3855 if (default_noexec && 3856 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3857 int rc = 0; 3858 /* 3859 * We don't use the vma_is_initial_heap() helper as it has 3860 * a history of problems and is currently broken on systems 3861 * where there is no heap, e.g. brk == start_brk. Before 3862 * replacing the conditional below with vma_is_initial_heap(), 3863 * or something similar, please ensure that the logic is the 3864 * same as what we have below or you have tested every possible 3865 * corner case you can think to test. 3866 */ 3867 if (vma->vm_start >= vma->vm_mm->start_brk && 3868 vma->vm_end <= vma->vm_mm->brk) { 3869 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3870 PROCESS__EXECHEAP, NULL); 3871 } else if (!vma->vm_file && (vma_is_initial_stack(vma) || 3872 vma_is_stack_for_current(vma))) { 3873 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3874 PROCESS__EXECSTACK, NULL); 3875 } else if (vma->vm_file && vma->anon_vma) { 3876 /* 3877 * We are making executable a file mapping that has 3878 * had some COW done. Since pages might have been 3879 * written, check ability to execute the possibly 3880 * modified content. This typically should only 3881 * occur for text relocations. 3882 */ 3883 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3884 } 3885 if (rc) 3886 return rc; 3887 } 3888 3889 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3890 } 3891 3892 static int selinux_file_lock(struct file *file, unsigned int cmd) 3893 { 3894 const struct cred *cred = current_cred(); 3895 3896 return file_has_perm(cred, file, FILE__LOCK); 3897 } 3898 3899 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3900 unsigned long arg) 3901 { 3902 const struct cred *cred = current_cred(); 3903 int err = 0; 3904 3905 switch (cmd) { 3906 case F_SETFL: 3907 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3908 err = file_has_perm(cred, file, FILE__WRITE); 3909 break; 3910 } 3911 fallthrough; 3912 case F_SETOWN: 3913 case F_SETSIG: 3914 case F_GETFL: 3915 case F_GETOWN: 3916 case F_GETSIG: 3917 case F_GETOWNER_UIDS: 3918 /* Just check FD__USE permission */ 3919 err = file_has_perm(cred, file, 0); 3920 break; 3921 case F_GETLK: 3922 case F_SETLK: 3923 case F_SETLKW: 3924 case F_OFD_GETLK: 3925 case F_OFD_SETLK: 3926 case F_OFD_SETLKW: 3927 #if BITS_PER_LONG == 32 3928 case F_GETLK64: 3929 case F_SETLK64: 3930 case F_SETLKW64: 3931 #endif 3932 err = file_has_perm(cred, file, FILE__LOCK); 3933 break; 3934 } 3935 3936 return err; 3937 } 3938 3939 static void selinux_file_set_fowner(struct file *file) 3940 { 3941 struct file_security_struct *fsec; 3942 3943 fsec = selinux_file(file); 3944 fsec->fown_sid = current_sid(); 3945 } 3946 3947 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3948 struct fown_struct *fown, int signum) 3949 { 3950 struct file *file; 3951 u32 sid = task_sid_obj(tsk); 3952 u32 perm; 3953 struct file_security_struct *fsec; 3954 3955 /* struct fown_struct is never outside the context of a struct file */ 3956 file = fown->file; 3957 3958 fsec = selinux_file(file); 3959 3960 if (!signum) 3961 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3962 else 3963 perm = signal_to_av(signum); 3964 3965 return avc_has_perm(fsec->fown_sid, sid, 3966 SECCLASS_PROCESS, perm, NULL); 3967 } 3968 3969 static int selinux_file_receive(struct file *file) 3970 { 3971 const struct cred *cred = current_cred(); 3972 3973 return file_has_perm(cred, file, file_to_av(file)); 3974 } 3975 3976 static int selinux_file_open(struct file *file) 3977 { 3978 struct file_security_struct *fsec; 3979 struct inode_security_struct *isec; 3980 3981 fsec = selinux_file(file); 3982 isec = inode_security(file_inode(file)); 3983 /* 3984 * Save inode label and policy sequence number 3985 * at open-time so that selinux_file_permission 3986 * can determine whether revalidation is necessary. 3987 * Task label is already saved in the file security 3988 * struct as its SID. 3989 */ 3990 fsec->isid = isec->sid; 3991 fsec->pseqno = avc_policy_seqno(); 3992 /* 3993 * Since the inode label or policy seqno may have changed 3994 * between the selinux_inode_permission check and the saving 3995 * of state above, recheck that access is still permitted. 3996 * Otherwise, access might never be revalidated against the 3997 * new inode label or new policy. 3998 * This check is not redundant - do not remove. 3999 */ 4000 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 4001 } 4002 4003 /* task security operations */ 4004 4005 static int selinux_task_alloc(struct task_struct *task, 4006 unsigned long clone_flags) 4007 { 4008 u32 sid = current_sid(); 4009 4010 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 4011 } 4012 4013 /* 4014 * prepare a new set of credentials for modification 4015 */ 4016 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 4017 gfp_t gfp) 4018 { 4019 const struct task_security_struct *old_tsec = selinux_cred(old); 4020 struct task_security_struct *tsec = selinux_cred(new); 4021 4022 *tsec = *old_tsec; 4023 return 0; 4024 } 4025 4026 /* 4027 * transfer the SELinux data to a blank set of creds 4028 */ 4029 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 4030 { 4031 const struct task_security_struct *old_tsec = selinux_cred(old); 4032 struct task_security_struct *tsec = selinux_cred(new); 4033 4034 *tsec = *old_tsec; 4035 } 4036 4037 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 4038 { 4039 *secid = cred_sid(c); 4040 } 4041 4042 static void selinux_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop) 4043 { 4044 prop->selinux.secid = cred_sid(c); 4045 } 4046 4047 /* 4048 * set the security data for a kernel service 4049 * - all the creation contexts are set to unlabelled 4050 */ 4051 static int selinux_kernel_act_as(struct cred *new, u32 secid) 4052 { 4053 struct task_security_struct *tsec = selinux_cred(new); 4054 u32 sid = current_sid(); 4055 int ret; 4056 4057 ret = avc_has_perm(sid, secid, 4058 SECCLASS_KERNEL_SERVICE, 4059 KERNEL_SERVICE__USE_AS_OVERRIDE, 4060 NULL); 4061 if (ret == 0) { 4062 tsec->sid = secid; 4063 tsec->create_sid = 0; 4064 tsec->keycreate_sid = 0; 4065 tsec->sockcreate_sid = 0; 4066 } 4067 return ret; 4068 } 4069 4070 /* 4071 * set the file creation context in a security record to the same as the 4072 * objective context of the specified inode 4073 */ 4074 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4075 { 4076 struct inode_security_struct *isec = inode_security(inode); 4077 struct task_security_struct *tsec = selinux_cred(new); 4078 u32 sid = current_sid(); 4079 int ret; 4080 4081 ret = avc_has_perm(sid, isec->sid, 4082 SECCLASS_KERNEL_SERVICE, 4083 KERNEL_SERVICE__CREATE_FILES_AS, 4084 NULL); 4085 4086 if (ret == 0) 4087 tsec->create_sid = isec->sid; 4088 return ret; 4089 } 4090 4091 static int selinux_kernel_module_request(char *kmod_name) 4092 { 4093 struct common_audit_data ad; 4094 4095 ad.type = LSM_AUDIT_DATA_KMOD; 4096 ad.u.kmod_name = kmod_name; 4097 4098 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4099 SYSTEM__MODULE_REQUEST, &ad); 4100 } 4101 4102 static int selinux_kernel_load_from_file(struct file *file, u32 requested) 4103 { 4104 struct common_audit_data ad; 4105 struct inode_security_struct *isec; 4106 struct file_security_struct *fsec; 4107 u32 sid = current_sid(); 4108 int rc; 4109 4110 if (file == NULL) 4111 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, requested, NULL); 4112 4113 ad.type = LSM_AUDIT_DATA_FILE; 4114 ad.u.file = file; 4115 4116 fsec = selinux_file(file); 4117 if (sid != fsec->sid) { 4118 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4119 if (rc) 4120 return rc; 4121 } 4122 4123 isec = inode_security(file_inode(file)); 4124 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, requested, &ad); 4125 } 4126 4127 static int selinux_kernel_read_file(struct file *file, 4128 enum kernel_read_file_id id, 4129 bool contents) 4130 { 4131 int rc = 0; 4132 4133 BUILD_BUG_ON_MSG(READING_MAX_ID > 7, 4134 "New kernel_read_file_id introduced; update SELinux!"); 4135 4136 switch (id) { 4137 case READING_FIRMWARE: 4138 rc = selinux_kernel_load_from_file(file, SYSTEM__FIRMWARE_LOAD); 4139 break; 4140 case READING_MODULE: 4141 rc = selinux_kernel_load_from_file(file, SYSTEM__MODULE_LOAD); 4142 break; 4143 case READING_KEXEC_IMAGE: 4144 rc = selinux_kernel_load_from_file(file, 4145 SYSTEM__KEXEC_IMAGE_LOAD); 4146 break; 4147 case READING_KEXEC_INITRAMFS: 4148 rc = selinux_kernel_load_from_file(file, 4149 SYSTEM__KEXEC_INITRAMFS_LOAD); 4150 break; 4151 case READING_POLICY: 4152 rc = selinux_kernel_load_from_file(file, SYSTEM__POLICY_LOAD); 4153 break; 4154 case READING_X509_CERTIFICATE: 4155 rc = selinux_kernel_load_from_file(file, 4156 SYSTEM__X509_CERTIFICATE_LOAD); 4157 break; 4158 default: 4159 break; 4160 } 4161 4162 return rc; 4163 } 4164 4165 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4166 { 4167 int rc = 0; 4168 4169 BUILD_BUG_ON_MSG(LOADING_MAX_ID > 7, 4170 "New kernel_load_data_id introduced; update SELinux!"); 4171 4172 switch (id) { 4173 case LOADING_FIRMWARE: 4174 rc = selinux_kernel_load_from_file(NULL, SYSTEM__FIRMWARE_LOAD); 4175 break; 4176 case LOADING_MODULE: 4177 rc = selinux_kernel_load_from_file(NULL, SYSTEM__MODULE_LOAD); 4178 break; 4179 case LOADING_KEXEC_IMAGE: 4180 rc = selinux_kernel_load_from_file(NULL, 4181 SYSTEM__KEXEC_IMAGE_LOAD); 4182 break; 4183 case LOADING_KEXEC_INITRAMFS: 4184 rc = selinux_kernel_load_from_file(NULL, 4185 SYSTEM__KEXEC_INITRAMFS_LOAD); 4186 break; 4187 case LOADING_POLICY: 4188 rc = selinux_kernel_load_from_file(NULL, 4189 SYSTEM__POLICY_LOAD); 4190 break; 4191 case LOADING_X509_CERTIFICATE: 4192 rc = selinux_kernel_load_from_file(NULL, 4193 SYSTEM__X509_CERTIFICATE_LOAD); 4194 break; 4195 default: 4196 break; 4197 } 4198 4199 return rc; 4200 } 4201 4202 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4203 { 4204 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4205 PROCESS__SETPGID, NULL); 4206 } 4207 4208 static int selinux_task_getpgid(struct task_struct *p) 4209 { 4210 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4211 PROCESS__GETPGID, NULL); 4212 } 4213 4214 static int selinux_task_getsid(struct task_struct *p) 4215 { 4216 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4217 PROCESS__GETSESSION, NULL); 4218 } 4219 4220 static void selinux_current_getlsmprop_subj(struct lsm_prop *prop) 4221 { 4222 prop->selinux.secid = current_sid(); 4223 } 4224 4225 static void selinux_task_getlsmprop_obj(struct task_struct *p, 4226 struct lsm_prop *prop) 4227 { 4228 prop->selinux.secid = task_sid_obj(p); 4229 } 4230 4231 static int selinux_task_setnice(struct task_struct *p, int nice) 4232 { 4233 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4234 PROCESS__SETSCHED, NULL); 4235 } 4236 4237 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4238 { 4239 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4240 PROCESS__SETSCHED, NULL); 4241 } 4242 4243 static int selinux_task_getioprio(struct task_struct *p) 4244 { 4245 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4246 PROCESS__GETSCHED, NULL); 4247 } 4248 4249 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4250 unsigned int flags) 4251 { 4252 u32 av = 0; 4253 4254 if (!flags) 4255 return 0; 4256 if (flags & LSM_PRLIMIT_WRITE) 4257 av |= PROCESS__SETRLIMIT; 4258 if (flags & LSM_PRLIMIT_READ) 4259 av |= PROCESS__GETRLIMIT; 4260 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4261 SECCLASS_PROCESS, av, NULL); 4262 } 4263 4264 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4265 struct rlimit *new_rlim) 4266 { 4267 struct rlimit *old_rlim = p->signal->rlim + resource; 4268 4269 /* Control the ability to change the hard limit (whether 4270 lowering or raising it), so that the hard limit can 4271 later be used as a safe reset point for the soft limit 4272 upon context transitions. See selinux_bprm_committing_creds. */ 4273 if (old_rlim->rlim_max != new_rlim->rlim_max) 4274 return avc_has_perm(current_sid(), task_sid_obj(p), 4275 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4276 4277 return 0; 4278 } 4279 4280 static int selinux_task_setscheduler(struct task_struct *p) 4281 { 4282 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4283 PROCESS__SETSCHED, NULL); 4284 } 4285 4286 static int selinux_task_getscheduler(struct task_struct *p) 4287 { 4288 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4289 PROCESS__GETSCHED, NULL); 4290 } 4291 4292 static int selinux_task_movememory(struct task_struct *p) 4293 { 4294 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4295 PROCESS__SETSCHED, NULL); 4296 } 4297 4298 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4299 int sig, const struct cred *cred) 4300 { 4301 u32 secid; 4302 u32 perm; 4303 4304 if (!sig) 4305 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4306 else 4307 perm = signal_to_av(sig); 4308 if (!cred) 4309 secid = current_sid(); 4310 else 4311 secid = cred_sid(cred); 4312 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4313 } 4314 4315 static void selinux_task_to_inode(struct task_struct *p, 4316 struct inode *inode) 4317 { 4318 struct inode_security_struct *isec = selinux_inode(inode); 4319 u32 sid = task_sid_obj(p); 4320 4321 spin_lock(&isec->lock); 4322 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4323 isec->sid = sid; 4324 isec->initialized = LABEL_INITIALIZED; 4325 spin_unlock(&isec->lock); 4326 } 4327 4328 static int selinux_userns_create(const struct cred *cred) 4329 { 4330 u32 sid = current_sid(); 4331 4332 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4333 USER_NAMESPACE__CREATE, NULL); 4334 } 4335 4336 /* Returns error only if unable to parse addresses */ 4337 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4338 struct common_audit_data *ad, u8 *proto) 4339 { 4340 int offset, ihlen, ret = -EINVAL; 4341 struct iphdr _iph, *ih; 4342 4343 offset = skb_network_offset(skb); 4344 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4345 if (ih == NULL) 4346 goto out; 4347 4348 ihlen = ih->ihl * 4; 4349 if (ihlen < sizeof(_iph)) 4350 goto out; 4351 4352 ad->u.net->v4info.saddr = ih->saddr; 4353 ad->u.net->v4info.daddr = ih->daddr; 4354 ret = 0; 4355 4356 if (proto) 4357 *proto = ih->protocol; 4358 4359 switch (ih->protocol) { 4360 case IPPROTO_TCP: { 4361 struct tcphdr _tcph, *th; 4362 4363 if (ntohs(ih->frag_off) & IP_OFFSET) 4364 break; 4365 4366 offset += ihlen; 4367 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4368 if (th == NULL) 4369 break; 4370 4371 ad->u.net->sport = th->source; 4372 ad->u.net->dport = th->dest; 4373 break; 4374 } 4375 4376 case IPPROTO_UDP: { 4377 struct udphdr _udph, *uh; 4378 4379 if (ntohs(ih->frag_off) & IP_OFFSET) 4380 break; 4381 4382 offset += ihlen; 4383 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4384 if (uh == NULL) 4385 break; 4386 4387 ad->u.net->sport = uh->source; 4388 ad->u.net->dport = uh->dest; 4389 break; 4390 } 4391 4392 case IPPROTO_DCCP: { 4393 struct dccp_hdr _dccph, *dh; 4394 4395 if (ntohs(ih->frag_off) & IP_OFFSET) 4396 break; 4397 4398 offset += ihlen; 4399 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4400 if (dh == NULL) 4401 break; 4402 4403 ad->u.net->sport = dh->dccph_sport; 4404 ad->u.net->dport = dh->dccph_dport; 4405 break; 4406 } 4407 4408 #if IS_ENABLED(CONFIG_IP_SCTP) 4409 case IPPROTO_SCTP: { 4410 struct sctphdr _sctph, *sh; 4411 4412 if (ntohs(ih->frag_off) & IP_OFFSET) 4413 break; 4414 4415 offset += ihlen; 4416 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4417 if (sh == NULL) 4418 break; 4419 4420 ad->u.net->sport = sh->source; 4421 ad->u.net->dport = sh->dest; 4422 break; 4423 } 4424 #endif 4425 default: 4426 break; 4427 } 4428 out: 4429 return ret; 4430 } 4431 4432 #if IS_ENABLED(CONFIG_IPV6) 4433 4434 /* Returns error only if unable to parse addresses */ 4435 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4436 struct common_audit_data *ad, u8 *proto) 4437 { 4438 u8 nexthdr; 4439 int ret = -EINVAL, offset; 4440 struct ipv6hdr _ipv6h, *ip6; 4441 __be16 frag_off; 4442 4443 offset = skb_network_offset(skb); 4444 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4445 if (ip6 == NULL) 4446 goto out; 4447 4448 ad->u.net->v6info.saddr = ip6->saddr; 4449 ad->u.net->v6info.daddr = ip6->daddr; 4450 ret = 0; 4451 4452 nexthdr = ip6->nexthdr; 4453 offset += sizeof(_ipv6h); 4454 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4455 if (offset < 0) 4456 goto out; 4457 4458 if (proto) 4459 *proto = nexthdr; 4460 4461 switch (nexthdr) { 4462 case IPPROTO_TCP: { 4463 struct tcphdr _tcph, *th; 4464 4465 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4466 if (th == NULL) 4467 break; 4468 4469 ad->u.net->sport = th->source; 4470 ad->u.net->dport = th->dest; 4471 break; 4472 } 4473 4474 case IPPROTO_UDP: { 4475 struct udphdr _udph, *uh; 4476 4477 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4478 if (uh == NULL) 4479 break; 4480 4481 ad->u.net->sport = uh->source; 4482 ad->u.net->dport = uh->dest; 4483 break; 4484 } 4485 4486 case IPPROTO_DCCP: { 4487 struct dccp_hdr _dccph, *dh; 4488 4489 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4490 if (dh == NULL) 4491 break; 4492 4493 ad->u.net->sport = dh->dccph_sport; 4494 ad->u.net->dport = dh->dccph_dport; 4495 break; 4496 } 4497 4498 #if IS_ENABLED(CONFIG_IP_SCTP) 4499 case IPPROTO_SCTP: { 4500 struct sctphdr _sctph, *sh; 4501 4502 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4503 if (sh == NULL) 4504 break; 4505 4506 ad->u.net->sport = sh->source; 4507 ad->u.net->dport = sh->dest; 4508 break; 4509 } 4510 #endif 4511 /* includes fragments */ 4512 default: 4513 break; 4514 } 4515 out: 4516 return ret; 4517 } 4518 4519 #endif /* IPV6 */ 4520 4521 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4522 char **_addrp, int src, u8 *proto) 4523 { 4524 char *addrp; 4525 int ret; 4526 4527 switch (ad->u.net->family) { 4528 case PF_INET: 4529 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4530 if (ret) 4531 goto parse_error; 4532 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4533 &ad->u.net->v4info.daddr); 4534 goto okay; 4535 4536 #if IS_ENABLED(CONFIG_IPV6) 4537 case PF_INET6: 4538 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4539 if (ret) 4540 goto parse_error; 4541 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4542 &ad->u.net->v6info.daddr); 4543 goto okay; 4544 #endif /* IPV6 */ 4545 default: 4546 addrp = NULL; 4547 goto okay; 4548 } 4549 4550 parse_error: 4551 pr_warn( 4552 "SELinux: failure in selinux_parse_skb()," 4553 " unable to parse packet\n"); 4554 return ret; 4555 4556 okay: 4557 if (_addrp) 4558 *_addrp = addrp; 4559 return 0; 4560 } 4561 4562 /** 4563 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4564 * @skb: the packet 4565 * @family: protocol family 4566 * @sid: the packet's peer label SID 4567 * 4568 * Description: 4569 * Check the various different forms of network peer labeling and determine 4570 * the peer label/SID for the packet; most of the magic actually occurs in 4571 * the security server function security_net_peersid_cmp(). The function 4572 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4573 * or -EACCES if @sid is invalid due to inconsistencies with the different 4574 * peer labels. 4575 * 4576 */ 4577 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4578 { 4579 int err; 4580 u32 xfrm_sid; 4581 u32 nlbl_sid; 4582 u32 nlbl_type; 4583 4584 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4585 if (unlikely(err)) 4586 return -EACCES; 4587 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4588 if (unlikely(err)) 4589 return -EACCES; 4590 4591 err = security_net_peersid_resolve(nlbl_sid, 4592 nlbl_type, xfrm_sid, sid); 4593 if (unlikely(err)) { 4594 pr_warn( 4595 "SELinux: failure in selinux_skb_peerlbl_sid()," 4596 " unable to determine packet's peer label\n"); 4597 return -EACCES; 4598 } 4599 4600 return 0; 4601 } 4602 4603 /** 4604 * selinux_conn_sid - Determine the child socket label for a connection 4605 * @sk_sid: the parent socket's SID 4606 * @skb_sid: the packet's SID 4607 * @conn_sid: the resulting connection SID 4608 * 4609 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4610 * combined with the MLS information from @skb_sid in order to create 4611 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4612 * of @sk_sid. Returns zero on success, negative values on failure. 4613 * 4614 */ 4615 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4616 { 4617 int err = 0; 4618 4619 if (skb_sid != SECSID_NULL) 4620 err = security_sid_mls_copy(sk_sid, skb_sid, 4621 conn_sid); 4622 else 4623 *conn_sid = sk_sid; 4624 4625 return err; 4626 } 4627 4628 /* socket security operations */ 4629 4630 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4631 u16 secclass, u32 *socksid) 4632 { 4633 if (tsec->sockcreate_sid > SECSID_NULL) { 4634 *socksid = tsec->sockcreate_sid; 4635 return 0; 4636 } 4637 4638 return security_transition_sid(tsec->sid, tsec->sid, 4639 secclass, NULL, socksid); 4640 } 4641 4642 static bool sock_skip_has_perm(u32 sid) 4643 { 4644 if (sid == SECINITSID_KERNEL) 4645 return true; 4646 4647 /* 4648 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that 4649 * inherited the kernel context from early boot used to be skipped 4650 * here, so preserve that behavior unless the capability is set. 4651 * 4652 * By setting the capability the policy signals that it is ready 4653 * for this quirk to be fixed. Note that sockets created by a kernel 4654 * thread or a usermode helper executed without a transition will 4655 * still be skipped in this check regardless of the policycap 4656 * setting. 4657 */ 4658 if (!selinux_policycap_userspace_initial_context() && 4659 sid == SECINITSID_INIT) 4660 return true; 4661 return false; 4662 } 4663 4664 4665 static int sock_has_perm(struct sock *sk, u32 perms) 4666 { 4667 struct sk_security_struct *sksec = sk->sk_security; 4668 struct common_audit_data ad; 4669 struct lsm_network_audit net; 4670 4671 if (sock_skip_has_perm(sksec->sid)) 4672 return 0; 4673 4674 ad_net_init_from_sk(&ad, &net, sk); 4675 4676 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4677 &ad); 4678 } 4679 4680 static int selinux_socket_create(int family, int type, 4681 int protocol, int kern) 4682 { 4683 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4684 u32 newsid; 4685 u16 secclass; 4686 int rc; 4687 4688 if (kern) 4689 return 0; 4690 4691 secclass = socket_type_to_security_class(family, type, protocol); 4692 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4693 if (rc) 4694 return rc; 4695 4696 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4697 } 4698 4699 static int selinux_socket_post_create(struct socket *sock, int family, 4700 int type, int protocol, int kern) 4701 { 4702 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4703 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4704 struct sk_security_struct *sksec; 4705 u16 sclass = socket_type_to_security_class(family, type, protocol); 4706 u32 sid = SECINITSID_KERNEL; 4707 int err = 0; 4708 4709 if (!kern) { 4710 err = socket_sockcreate_sid(tsec, sclass, &sid); 4711 if (err) 4712 return err; 4713 } 4714 4715 isec->sclass = sclass; 4716 isec->sid = sid; 4717 isec->initialized = LABEL_INITIALIZED; 4718 4719 if (sock->sk) { 4720 sksec = selinux_sock(sock->sk); 4721 sksec->sclass = sclass; 4722 sksec->sid = sid; 4723 /* Allows detection of the first association on this socket */ 4724 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4725 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4726 4727 err = selinux_netlbl_socket_post_create(sock->sk, family); 4728 } 4729 4730 return err; 4731 } 4732 4733 static int selinux_socket_socketpair(struct socket *socka, 4734 struct socket *sockb) 4735 { 4736 struct sk_security_struct *sksec_a = selinux_sock(socka->sk); 4737 struct sk_security_struct *sksec_b = selinux_sock(sockb->sk); 4738 4739 sksec_a->peer_sid = sksec_b->sid; 4740 sksec_b->peer_sid = sksec_a->sid; 4741 4742 return 0; 4743 } 4744 4745 /* Range of port numbers used to automatically bind. 4746 Need to determine whether we should perform a name_bind 4747 permission check between the socket and the port number. */ 4748 4749 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4750 { 4751 struct sock *sk = sock->sk; 4752 struct sk_security_struct *sksec = selinux_sock(sk); 4753 u16 family; 4754 int err; 4755 4756 err = sock_has_perm(sk, SOCKET__BIND); 4757 if (err) 4758 goto out; 4759 4760 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4761 family = sk->sk_family; 4762 if (family == PF_INET || family == PF_INET6) { 4763 char *addrp; 4764 struct common_audit_data ad; 4765 struct lsm_network_audit net = {0,}; 4766 struct sockaddr_in *addr4 = NULL; 4767 struct sockaddr_in6 *addr6 = NULL; 4768 u16 family_sa; 4769 unsigned short snum; 4770 u32 sid, node_perm; 4771 4772 /* 4773 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4774 * that validates multiple binding addresses. Because of this 4775 * need to check address->sa_family as it is possible to have 4776 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4777 */ 4778 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4779 return -EINVAL; 4780 family_sa = address->sa_family; 4781 switch (family_sa) { 4782 case AF_UNSPEC: 4783 case AF_INET: 4784 if (addrlen < sizeof(struct sockaddr_in)) 4785 return -EINVAL; 4786 addr4 = (struct sockaddr_in *)address; 4787 if (family_sa == AF_UNSPEC) { 4788 if (family == PF_INET6) { 4789 /* Length check from inet6_bind_sk() */ 4790 if (addrlen < SIN6_LEN_RFC2133) 4791 return -EINVAL; 4792 /* Family check from __inet6_bind() */ 4793 goto err_af; 4794 } 4795 /* see __inet_bind(), we only want to allow 4796 * AF_UNSPEC if the address is INADDR_ANY 4797 */ 4798 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4799 goto err_af; 4800 family_sa = AF_INET; 4801 } 4802 snum = ntohs(addr4->sin_port); 4803 addrp = (char *)&addr4->sin_addr.s_addr; 4804 break; 4805 case AF_INET6: 4806 if (addrlen < SIN6_LEN_RFC2133) 4807 return -EINVAL; 4808 addr6 = (struct sockaddr_in6 *)address; 4809 snum = ntohs(addr6->sin6_port); 4810 addrp = (char *)&addr6->sin6_addr.s6_addr; 4811 break; 4812 default: 4813 goto err_af; 4814 } 4815 4816 ad.type = LSM_AUDIT_DATA_NET; 4817 ad.u.net = &net; 4818 ad.u.net->sport = htons(snum); 4819 ad.u.net->family = family_sa; 4820 4821 if (snum) { 4822 int low, high; 4823 4824 inet_get_local_port_range(sock_net(sk), &low, &high); 4825 4826 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4827 snum < low || snum > high) { 4828 err = sel_netport_sid(sk->sk_protocol, 4829 snum, &sid); 4830 if (err) 4831 goto out; 4832 err = avc_has_perm(sksec->sid, sid, 4833 sksec->sclass, 4834 SOCKET__NAME_BIND, &ad); 4835 if (err) 4836 goto out; 4837 } 4838 } 4839 4840 switch (sksec->sclass) { 4841 case SECCLASS_TCP_SOCKET: 4842 node_perm = TCP_SOCKET__NODE_BIND; 4843 break; 4844 4845 case SECCLASS_UDP_SOCKET: 4846 node_perm = UDP_SOCKET__NODE_BIND; 4847 break; 4848 4849 case SECCLASS_DCCP_SOCKET: 4850 node_perm = DCCP_SOCKET__NODE_BIND; 4851 break; 4852 4853 case SECCLASS_SCTP_SOCKET: 4854 node_perm = SCTP_SOCKET__NODE_BIND; 4855 break; 4856 4857 default: 4858 node_perm = RAWIP_SOCKET__NODE_BIND; 4859 break; 4860 } 4861 4862 err = sel_netnode_sid(addrp, family_sa, &sid); 4863 if (err) 4864 goto out; 4865 4866 if (family_sa == AF_INET) 4867 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4868 else 4869 ad.u.net->v6info.saddr = addr6->sin6_addr; 4870 4871 err = avc_has_perm(sksec->sid, sid, 4872 sksec->sclass, node_perm, &ad); 4873 if (err) 4874 goto out; 4875 } 4876 out: 4877 return err; 4878 err_af: 4879 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4880 if (sk->sk_protocol == IPPROTO_SCTP) 4881 return -EINVAL; 4882 return -EAFNOSUPPORT; 4883 } 4884 4885 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4886 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4887 */ 4888 static int selinux_socket_connect_helper(struct socket *sock, 4889 struct sockaddr *address, int addrlen) 4890 { 4891 struct sock *sk = sock->sk; 4892 struct sk_security_struct *sksec = selinux_sock(sk); 4893 int err; 4894 4895 err = sock_has_perm(sk, SOCKET__CONNECT); 4896 if (err) 4897 return err; 4898 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4899 return -EINVAL; 4900 4901 /* connect(AF_UNSPEC) has special handling, as it is a documented 4902 * way to disconnect the socket 4903 */ 4904 if (address->sa_family == AF_UNSPEC) 4905 return 0; 4906 4907 /* 4908 * If a TCP, DCCP or SCTP socket, check name_connect permission 4909 * for the port. 4910 */ 4911 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4912 sksec->sclass == SECCLASS_DCCP_SOCKET || 4913 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4914 struct common_audit_data ad; 4915 struct lsm_network_audit net = {0,}; 4916 struct sockaddr_in *addr4 = NULL; 4917 struct sockaddr_in6 *addr6 = NULL; 4918 unsigned short snum; 4919 u32 sid, perm; 4920 4921 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4922 * that validates multiple connect addresses. Because of this 4923 * need to check address->sa_family as it is possible to have 4924 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4925 */ 4926 switch (address->sa_family) { 4927 case AF_INET: 4928 addr4 = (struct sockaddr_in *)address; 4929 if (addrlen < sizeof(struct sockaddr_in)) 4930 return -EINVAL; 4931 snum = ntohs(addr4->sin_port); 4932 break; 4933 case AF_INET6: 4934 addr6 = (struct sockaddr_in6 *)address; 4935 if (addrlen < SIN6_LEN_RFC2133) 4936 return -EINVAL; 4937 snum = ntohs(addr6->sin6_port); 4938 break; 4939 default: 4940 /* Note that SCTP services expect -EINVAL, whereas 4941 * others expect -EAFNOSUPPORT. 4942 */ 4943 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4944 return -EINVAL; 4945 else 4946 return -EAFNOSUPPORT; 4947 } 4948 4949 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4950 if (err) 4951 return err; 4952 4953 switch (sksec->sclass) { 4954 case SECCLASS_TCP_SOCKET: 4955 perm = TCP_SOCKET__NAME_CONNECT; 4956 break; 4957 case SECCLASS_DCCP_SOCKET: 4958 perm = DCCP_SOCKET__NAME_CONNECT; 4959 break; 4960 case SECCLASS_SCTP_SOCKET: 4961 perm = SCTP_SOCKET__NAME_CONNECT; 4962 break; 4963 } 4964 4965 ad.type = LSM_AUDIT_DATA_NET; 4966 ad.u.net = &net; 4967 ad.u.net->dport = htons(snum); 4968 ad.u.net->family = address->sa_family; 4969 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4970 if (err) 4971 return err; 4972 } 4973 4974 return 0; 4975 } 4976 4977 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4978 static int selinux_socket_connect(struct socket *sock, 4979 struct sockaddr *address, int addrlen) 4980 { 4981 int err; 4982 struct sock *sk = sock->sk; 4983 4984 err = selinux_socket_connect_helper(sock, address, addrlen); 4985 if (err) 4986 return err; 4987 4988 return selinux_netlbl_socket_connect(sk, address); 4989 } 4990 4991 static int selinux_socket_listen(struct socket *sock, int backlog) 4992 { 4993 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4994 } 4995 4996 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4997 { 4998 int err; 4999 struct inode_security_struct *isec; 5000 struct inode_security_struct *newisec; 5001 u16 sclass; 5002 u32 sid; 5003 5004 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 5005 if (err) 5006 return err; 5007 5008 isec = inode_security_novalidate(SOCK_INODE(sock)); 5009 spin_lock(&isec->lock); 5010 sclass = isec->sclass; 5011 sid = isec->sid; 5012 spin_unlock(&isec->lock); 5013 5014 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 5015 newisec->sclass = sclass; 5016 newisec->sid = sid; 5017 newisec->initialized = LABEL_INITIALIZED; 5018 5019 return 0; 5020 } 5021 5022 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 5023 int size) 5024 { 5025 return sock_has_perm(sock->sk, SOCKET__WRITE); 5026 } 5027 5028 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 5029 int size, int flags) 5030 { 5031 return sock_has_perm(sock->sk, SOCKET__READ); 5032 } 5033 5034 static int selinux_socket_getsockname(struct socket *sock) 5035 { 5036 return sock_has_perm(sock->sk, SOCKET__GETATTR); 5037 } 5038 5039 static int selinux_socket_getpeername(struct socket *sock) 5040 { 5041 return sock_has_perm(sock->sk, SOCKET__GETATTR); 5042 } 5043 5044 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 5045 { 5046 int err; 5047 5048 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 5049 if (err) 5050 return err; 5051 5052 return selinux_netlbl_socket_setsockopt(sock, level, optname); 5053 } 5054 5055 static int selinux_socket_getsockopt(struct socket *sock, int level, 5056 int optname) 5057 { 5058 return sock_has_perm(sock->sk, SOCKET__GETOPT); 5059 } 5060 5061 static int selinux_socket_shutdown(struct socket *sock, int how) 5062 { 5063 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 5064 } 5065 5066 static int selinux_socket_unix_stream_connect(struct sock *sock, 5067 struct sock *other, 5068 struct sock *newsk) 5069 { 5070 struct sk_security_struct *sksec_sock = selinux_sock(sock); 5071 struct sk_security_struct *sksec_other = selinux_sock(other); 5072 struct sk_security_struct *sksec_new = selinux_sock(newsk); 5073 struct common_audit_data ad; 5074 struct lsm_network_audit net; 5075 int err; 5076 5077 ad_net_init_from_sk(&ad, &net, other); 5078 5079 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 5080 sksec_other->sclass, 5081 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 5082 if (err) 5083 return err; 5084 5085 /* server child socket */ 5086 sksec_new->peer_sid = sksec_sock->sid; 5087 err = security_sid_mls_copy(sksec_other->sid, 5088 sksec_sock->sid, &sksec_new->sid); 5089 if (err) 5090 return err; 5091 5092 /* connecting socket */ 5093 sksec_sock->peer_sid = sksec_new->sid; 5094 5095 return 0; 5096 } 5097 5098 static int selinux_socket_unix_may_send(struct socket *sock, 5099 struct socket *other) 5100 { 5101 struct sk_security_struct *ssec = selinux_sock(sock->sk); 5102 struct sk_security_struct *osec = selinux_sock(other->sk); 5103 struct common_audit_data ad; 5104 struct lsm_network_audit net; 5105 5106 ad_net_init_from_sk(&ad, &net, other->sk); 5107 5108 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 5109 &ad); 5110 } 5111 5112 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 5113 char *addrp, u16 family, u32 peer_sid, 5114 struct common_audit_data *ad) 5115 { 5116 int err; 5117 u32 if_sid; 5118 u32 node_sid; 5119 5120 err = sel_netif_sid(ns, ifindex, &if_sid); 5121 if (err) 5122 return err; 5123 err = avc_has_perm(peer_sid, if_sid, 5124 SECCLASS_NETIF, NETIF__INGRESS, ad); 5125 if (err) 5126 return err; 5127 5128 err = sel_netnode_sid(addrp, family, &node_sid); 5129 if (err) 5130 return err; 5131 return avc_has_perm(peer_sid, node_sid, 5132 SECCLASS_NODE, NODE__RECVFROM, ad); 5133 } 5134 5135 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5136 u16 family) 5137 { 5138 int err = 0; 5139 struct sk_security_struct *sksec = selinux_sock(sk); 5140 u32 sk_sid = sksec->sid; 5141 struct common_audit_data ad; 5142 struct lsm_network_audit net; 5143 char *addrp; 5144 5145 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5146 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5147 if (err) 5148 return err; 5149 5150 if (selinux_secmark_enabled()) { 5151 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5152 PACKET__RECV, &ad); 5153 if (err) 5154 return err; 5155 } 5156 5157 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5158 if (err) 5159 return err; 5160 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5161 5162 return err; 5163 } 5164 5165 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5166 { 5167 int err, peerlbl_active, secmark_active; 5168 struct sk_security_struct *sksec = selinux_sock(sk); 5169 u16 family = sk->sk_family; 5170 u32 sk_sid = sksec->sid; 5171 struct common_audit_data ad; 5172 struct lsm_network_audit net; 5173 char *addrp; 5174 5175 if (family != PF_INET && family != PF_INET6) 5176 return 0; 5177 5178 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5179 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5180 family = PF_INET; 5181 5182 /* If any sort of compatibility mode is enabled then handoff processing 5183 * to the selinux_sock_rcv_skb_compat() function to deal with the 5184 * special handling. We do this in an attempt to keep this function 5185 * as fast and as clean as possible. */ 5186 if (!selinux_policycap_netpeer()) 5187 return selinux_sock_rcv_skb_compat(sk, skb, family); 5188 5189 secmark_active = selinux_secmark_enabled(); 5190 peerlbl_active = selinux_peerlbl_enabled(); 5191 if (!secmark_active && !peerlbl_active) 5192 return 0; 5193 5194 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5195 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5196 if (err) 5197 return err; 5198 5199 if (peerlbl_active) { 5200 u32 peer_sid; 5201 5202 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5203 if (err) 5204 return err; 5205 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5206 addrp, family, peer_sid, &ad); 5207 if (err) { 5208 selinux_netlbl_err(skb, family, err, 0); 5209 return err; 5210 } 5211 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5212 PEER__RECV, &ad); 5213 if (err) { 5214 selinux_netlbl_err(skb, family, err, 0); 5215 return err; 5216 } 5217 } 5218 5219 if (secmark_active) { 5220 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5221 PACKET__RECV, &ad); 5222 if (err) 5223 return err; 5224 } 5225 5226 return err; 5227 } 5228 5229 static int selinux_socket_getpeersec_stream(struct socket *sock, 5230 sockptr_t optval, sockptr_t optlen, 5231 unsigned int len) 5232 { 5233 int err = 0; 5234 char *scontext = NULL; 5235 u32 scontext_len; 5236 struct sk_security_struct *sksec = selinux_sock(sock->sk); 5237 u32 peer_sid = SECSID_NULL; 5238 5239 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5240 sksec->sclass == SECCLASS_TCP_SOCKET || 5241 sksec->sclass == SECCLASS_SCTP_SOCKET) 5242 peer_sid = sksec->peer_sid; 5243 if (peer_sid == SECSID_NULL) 5244 return -ENOPROTOOPT; 5245 5246 err = security_sid_to_context(peer_sid, &scontext, 5247 &scontext_len); 5248 if (err) 5249 return err; 5250 if (scontext_len > len) { 5251 err = -ERANGE; 5252 goto out_len; 5253 } 5254 5255 if (copy_to_sockptr(optval, scontext, scontext_len)) 5256 err = -EFAULT; 5257 out_len: 5258 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5259 err = -EFAULT; 5260 kfree(scontext); 5261 return err; 5262 } 5263 5264 static int selinux_socket_getpeersec_dgram(struct socket *sock, 5265 struct sk_buff *skb, u32 *secid) 5266 { 5267 u32 peer_secid = SECSID_NULL; 5268 u16 family; 5269 5270 if (skb && skb->protocol == htons(ETH_P_IP)) 5271 family = PF_INET; 5272 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5273 family = PF_INET6; 5274 else if (sock) 5275 family = sock->sk->sk_family; 5276 else { 5277 *secid = SECSID_NULL; 5278 return -EINVAL; 5279 } 5280 5281 if (sock && family == PF_UNIX) { 5282 struct inode_security_struct *isec; 5283 isec = inode_security_novalidate(SOCK_INODE(sock)); 5284 peer_secid = isec->sid; 5285 } else if (skb) 5286 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5287 5288 *secid = peer_secid; 5289 if (peer_secid == SECSID_NULL) 5290 return -ENOPROTOOPT; 5291 return 0; 5292 } 5293 5294 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5295 { 5296 struct sk_security_struct *sksec = selinux_sock(sk); 5297 5298 sksec->peer_sid = SECINITSID_UNLABELED; 5299 sksec->sid = SECINITSID_UNLABELED; 5300 sksec->sclass = SECCLASS_SOCKET; 5301 selinux_netlbl_sk_security_reset(sksec); 5302 5303 return 0; 5304 } 5305 5306 static void selinux_sk_free_security(struct sock *sk) 5307 { 5308 struct sk_security_struct *sksec = selinux_sock(sk); 5309 5310 selinux_netlbl_sk_security_free(sksec); 5311 } 5312 5313 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5314 { 5315 struct sk_security_struct *sksec = selinux_sock(sk); 5316 struct sk_security_struct *newsksec = selinux_sock(newsk); 5317 5318 newsksec->sid = sksec->sid; 5319 newsksec->peer_sid = sksec->peer_sid; 5320 newsksec->sclass = sksec->sclass; 5321 5322 selinux_netlbl_sk_security_reset(newsksec); 5323 } 5324 5325 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5326 { 5327 if (!sk) 5328 *secid = SECINITSID_ANY_SOCKET; 5329 else { 5330 const struct sk_security_struct *sksec = selinux_sock(sk); 5331 5332 *secid = sksec->sid; 5333 } 5334 } 5335 5336 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5337 { 5338 struct inode_security_struct *isec = 5339 inode_security_novalidate(SOCK_INODE(parent)); 5340 struct sk_security_struct *sksec = selinux_sock(sk); 5341 5342 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5343 sk->sk_family == PF_UNIX) 5344 isec->sid = sksec->sid; 5345 sksec->sclass = isec->sclass; 5346 } 5347 5348 /* 5349 * Determines peer_secid for the asoc and updates socket's peer label 5350 * if it's the first association on the socket. 5351 */ 5352 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5353 struct sk_buff *skb) 5354 { 5355 struct sock *sk = asoc->base.sk; 5356 u16 family = sk->sk_family; 5357 struct sk_security_struct *sksec = selinux_sock(sk); 5358 struct common_audit_data ad; 5359 struct lsm_network_audit net; 5360 int err; 5361 5362 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5363 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5364 family = PF_INET; 5365 5366 if (selinux_peerlbl_enabled()) { 5367 asoc->peer_secid = SECSID_NULL; 5368 5369 /* This will return peer_sid = SECSID_NULL if there are 5370 * no peer labels, see security_net_peersid_resolve(). 5371 */ 5372 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5373 if (err) 5374 return err; 5375 5376 if (asoc->peer_secid == SECSID_NULL) 5377 asoc->peer_secid = SECINITSID_UNLABELED; 5378 } else { 5379 asoc->peer_secid = SECINITSID_UNLABELED; 5380 } 5381 5382 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5383 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5384 5385 /* Here as first association on socket. As the peer SID 5386 * was allowed by peer recv (and the netif/node checks), 5387 * then it is approved by policy and used as the primary 5388 * peer SID for getpeercon(3). 5389 */ 5390 sksec->peer_sid = asoc->peer_secid; 5391 } else if (sksec->peer_sid != asoc->peer_secid) { 5392 /* Other association peer SIDs are checked to enforce 5393 * consistency among the peer SIDs. 5394 */ 5395 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5396 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5397 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5398 &ad); 5399 if (err) 5400 return err; 5401 } 5402 return 0; 5403 } 5404 5405 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5406 * happens on an incoming connect(2), sctp_connectx(3) or 5407 * sctp_sendmsg(3) (with no association already present). 5408 */ 5409 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5410 struct sk_buff *skb) 5411 { 5412 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk); 5413 u32 conn_sid; 5414 int err; 5415 5416 if (!selinux_policycap_extsockclass()) 5417 return 0; 5418 5419 err = selinux_sctp_process_new_assoc(asoc, skb); 5420 if (err) 5421 return err; 5422 5423 /* Compute the MLS component for the connection and store 5424 * the information in asoc. This will be used by SCTP TCP type 5425 * sockets and peeled off connections as they cause a new 5426 * socket to be generated. selinux_sctp_sk_clone() will then 5427 * plug this into the new socket. 5428 */ 5429 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5430 if (err) 5431 return err; 5432 5433 asoc->secid = conn_sid; 5434 5435 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5436 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5437 } 5438 5439 /* Called when SCTP receives a COOKIE ACK chunk as the final 5440 * response to an association request (initited by us). 5441 */ 5442 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5443 struct sk_buff *skb) 5444 { 5445 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk); 5446 5447 if (!selinux_policycap_extsockclass()) 5448 return 0; 5449 5450 /* Inherit secid from the parent socket - this will be picked up 5451 * by selinux_sctp_sk_clone() if the association gets peeled off 5452 * into a new socket. 5453 */ 5454 asoc->secid = sksec->sid; 5455 5456 return selinux_sctp_process_new_assoc(asoc, skb); 5457 } 5458 5459 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5460 * based on their @optname. 5461 */ 5462 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5463 struct sockaddr *address, 5464 int addrlen) 5465 { 5466 int len, err = 0, walk_size = 0; 5467 void *addr_buf; 5468 struct sockaddr *addr; 5469 struct socket *sock; 5470 5471 if (!selinux_policycap_extsockclass()) 5472 return 0; 5473 5474 /* Process one or more addresses that may be IPv4 or IPv6 */ 5475 sock = sk->sk_socket; 5476 addr_buf = address; 5477 5478 while (walk_size < addrlen) { 5479 if (walk_size + sizeof(sa_family_t) > addrlen) 5480 return -EINVAL; 5481 5482 addr = addr_buf; 5483 switch (addr->sa_family) { 5484 case AF_UNSPEC: 5485 case AF_INET: 5486 len = sizeof(struct sockaddr_in); 5487 break; 5488 case AF_INET6: 5489 len = sizeof(struct sockaddr_in6); 5490 break; 5491 default: 5492 return -EINVAL; 5493 } 5494 5495 if (walk_size + len > addrlen) 5496 return -EINVAL; 5497 5498 err = -EINVAL; 5499 switch (optname) { 5500 /* Bind checks */ 5501 case SCTP_PRIMARY_ADDR: 5502 case SCTP_SET_PEER_PRIMARY_ADDR: 5503 case SCTP_SOCKOPT_BINDX_ADD: 5504 err = selinux_socket_bind(sock, addr, len); 5505 break; 5506 /* Connect checks */ 5507 case SCTP_SOCKOPT_CONNECTX: 5508 case SCTP_PARAM_SET_PRIMARY: 5509 case SCTP_PARAM_ADD_IP: 5510 case SCTP_SENDMSG_CONNECT: 5511 err = selinux_socket_connect_helper(sock, addr, len); 5512 if (err) 5513 return err; 5514 5515 /* As selinux_sctp_bind_connect() is called by the 5516 * SCTP protocol layer, the socket is already locked, 5517 * therefore selinux_netlbl_socket_connect_locked() 5518 * is called here. The situations handled are: 5519 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5520 * whenever a new IP address is added or when a new 5521 * primary address is selected. 5522 * Note that an SCTP connect(2) call happens before 5523 * the SCTP protocol layer and is handled via 5524 * selinux_socket_connect(). 5525 */ 5526 err = selinux_netlbl_socket_connect_locked(sk, addr); 5527 break; 5528 } 5529 5530 if (err) 5531 return err; 5532 5533 addr_buf += len; 5534 walk_size += len; 5535 } 5536 5537 return 0; 5538 } 5539 5540 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5541 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5542 struct sock *newsk) 5543 { 5544 struct sk_security_struct *sksec = selinux_sock(sk); 5545 struct sk_security_struct *newsksec = selinux_sock(newsk); 5546 5547 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5548 * the non-sctp clone version. 5549 */ 5550 if (!selinux_policycap_extsockclass()) 5551 return selinux_sk_clone_security(sk, newsk); 5552 5553 newsksec->sid = asoc->secid; 5554 newsksec->peer_sid = asoc->peer_secid; 5555 newsksec->sclass = sksec->sclass; 5556 selinux_netlbl_sctp_sk_clone(sk, newsk); 5557 } 5558 5559 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5560 { 5561 struct sk_security_struct *ssksec = selinux_sock(ssk); 5562 struct sk_security_struct *sksec = selinux_sock(sk); 5563 5564 ssksec->sclass = sksec->sclass; 5565 ssksec->sid = sksec->sid; 5566 5567 /* replace the existing subflow label deleting the existing one 5568 * and re-recreating a new label using the updated context 5569 */ 5570 selinux_netlbl_sk_security_free(ssksec); 5571 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5572 } 5573 5574 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5575 struct request_sock *req) 5576 { 5577 struct sk_security_struct *sksec = selinux_sock(sk); 5578 int err; 5579 u16 family = req->rsk_ops->family; 5580 u32 connsid; 5581 u32 peersid; 5582 5583 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5584 if (err) 5585 return err; 5586 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5587 if (err) 5588 return err; 5589 req->secid = connsid; 5590 req->peer_secid = peersid; 5591 5592 return selinux_netlbl_inet_conn_request(req, family); 5593 } 5594 5595 static void selinux_inet_csk_clone(struct sock *newsk, 5596 const struct request_sock *req) 5597 { 5598 struct sk_security_struct *newsksec = selinux_sock(newsk); 5599 5600 newsksec->sid = req->secid; 5601 newsksec->peer_sid = req->peer_secid; 5602 /* NOTE: Ideally, we should also get the isec->sid for the 5603 new socket in sync, but we don't have the isec available yet. 5604 So we will wait until sock_graft to do it, by which 5605 time it will have been created and available. */ 5606 5607 /* We don't need to take any sort of lock here as we are the only 5608 * thread with access to newsksec */ 5609 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5610 } 5611 5612 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5613 { 5614 u16 family = sk->sk_family; 5615 struct sk_security_struct *sksec = selinux_sock(sk); 5616 5617 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5618 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5619 family = PF_INET; 5620 5621 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5622 } 5623 5624 static int selinux_secmark_relabel_packet(u32 sid) 5625 { 5626 return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO, 5627 NULL); 5628 } 5629 5630 static void selinux_secmark_refcount_inc(void) 5631 { 5632 atomic_inc(&selinux_secmark_refcount); 5633 } 5634 5635 static void selinux_secmark_refcount_dec(void) 5636 { 5637 atomic_dec(&selinux_secmark_refcount); 5638 } 5639 5640 static void selinux_req_classify_flow(const struct request_sock *req, 5641 struct flowi_common *flic) 5642 { 5643 flic->flowic_secid = req->secid; 5644 } 5645 5646 static int selinux_tun_dev_alloc_security(void *security) 5647 { 5648 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5649 5650 tunsec->sid = current_sid(); 5651 return 0; 5652 } 5653 5654 static int selinux_tun_dev_create(void) 5655 { 5656 u32 sid = current_sid(); 5657 5658 /* we aren't taking into account the "sockcreate" SID since the socket 5659 * that is being created here is not a socket in the traditional sense, 5660 * instead it is a private sock, accessible only to the kernel, and 5661 * representing a wide range of network traffic spanning multiple 5662 * connections unlike traditional sockets - check the TUN driver to 5663 * get a better understanding of why this socket is special */ 5664 5665 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5666 NULL); 5667 } 5668 5669 static int selinux_tun_dev_attach_queue(void *security) 5670 { 5671 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5672 5673 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5674 TUN_SOCKET__ATTACH_QUEUE, NULL); 5675 } 5676 5677 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5678 { 5679 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5680 struct sk_security_struct *sksec = selinux_sock(sk); 5681 5682 /* we don't currently perform any NetLabel based labeling here and it 5683 * isn't clear that we would want to do so anyway; while we could apply 5684 * labeling without the support of the TUN user the resulting labeled 5685 * traffic from the other end of the connection would almost certainly 5686 * cause confusion to the TUN user that had no idea network labeling 5687 * protocols were being used */ 5688 5689 sksec->sid = tunsec->sid; 5690 sksec->sclass = SECCLASS_TUN_SOCKET; 5691 5692 return 0; 5693 } 5694 5695 static int selinux_tun_dev_open(void *security) 5696 { 5697 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5698 u32 sid = current_sid(); 5699 int err; 5700 5701 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5702 TUN_SOCKET__RELABELFROM, NULL); 5703 if (err) 5704 return err; 5705 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5706 TUN_SOCKET__RELABELTO, NULL); 5707 if (err) 5708 return err; 5709 tunsec->sid = sid; 5710 5711 return 0; 5712 } 5713 5714 #ifdef CONFIG_NETFILTER 5715 5716 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5717 const struct nf_hook_state *state) 5718 { 5719 int ifindex; 5720 u16 family; 5721 char *addrp; 5722 u32 peer_sid; 5723 struct common_audit_data ad; 5724 struct lsm_network_audit net; 5725 int secmark_active, peerlbl_active; 5726 5727 if (!selinux_policycap_netpeer()) 5728 return NF_ACCEPT; 5729 5730 secmark_active = selinux_secmark_enabled(); 5731 peerlbl_active = selinux_peerlbl_enabled(); 5732 if (!secmark_active && !peerlbl_active) 5733 return NF_ACCEPT; 5734 5735 family = state->pf; 5736 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5737 return NF_DROP; 5738 5739 ifindex = state->in->ifindex; 5740 ad_net_init_from_iif(&ad, &net, ifindex, family); 5741 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5742 return NF_DROP; 5743 5744 if (peerlbl_active) { 5745 int err; 5746 5747 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5748 addrp, family, peer_sid, &ad); 5749 if (err) { 5750 selinux_netlbl_err(skb, family, err, 1); 5751 return NF_DROP; 5752 } 5753 } 5754 5755 if (secmark_active) 5756 if (avc_has_perm(peer_sid, skb->secmark, 5757 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5758 return NF_DROP; 5759 5760 if (netlbl_enabled()) 5761 /* we do this in the FORWARD path and not the POST_ROUTING 5762 * path because we want to make sure we apply the necessary 5763 * labeling before IPsec is applied so we can leverage AH 5764 * protection */ 5765 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5766 return NF_DROP; 5767 5768 return NF_ACCEPT; 5769 } 5770 5771 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5772 const struct nf_hook_state *state) 5773 { 5774 struct sock *sk; 5775 u32 sid; 5776 5777 if (!netlbl_enabled()) 5778 return NF_ACCEPT; 5779 5780 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5781 * because we want to make sure we apply the necessary labeling 5782 * before IPsec is applied so we can leverage AH protection */ 5783 sk = sk_to_full_sk(skb->sk); 5784 if (sk) { 5785 struct sk_security_struct *sksec; 5786 5787 if (sk_listener(sk)) 5788 /* if the socket is the listening state then this 5789 * packet is a SYN-ACK packet which means it needs to 5790 * be labeled based on the connection/request_sock and 5791 * not the parent socket. unfortunately, we can't 5792 * lookup the request_sock yet as it isn't queued on 5793 * the parent socket until after the SYN-ACK is sent. 5794 * the "solution" is to simply pass the packet as-is 5795 * as any IP option based labeling should be copied 5796 * from the initial connection request (in the IP 5797 * layer). it is far from ideal, but until we get a 5798 * security label in the packet itself this is the 5799 * best we can do. */ 5800 return NF_ACCEPT; 5801 5802 /* standard practice, label using the parent socket */ 5803 sksec = selinux_sock(sk); 5804 sid = sksec->sid; 5805 } else 5806 sid = SECINITSID_KERNEL; 5807 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5808 return NF_DROP; 5809 5810 return NF_ACCEPT; 5811 } 5812 5813 5814 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5815 const struct nf_hook_state *state) 5816 { 5817 struct sock *sk; 5818 struct sk_security_struct *sksec; 5819 struct common_audit_data ad; 5820 struct lsm_network_audit net; 5821 u8 proto = 0; 5822 5823 sk = skb_to_full_sk(skb); 5824 if (sk == NULL) 5825 return NF_ACCEPT; 5826 sksec = selinux_sock(sk); 5827 5828 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5829 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5830 return NF_DROP; 5831 5832 if (selinux_secmark_enabled()) 5833 if (avc_has_perm(sksec->sid, skb->secmark, 5834 SECCLASS_PACKET, PACKET__SEND, &ad)) 5835 return NF_DROP_ERR(-ECONNREFUSED); 5836 5837 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5838 return NF_DROP_ERR(-ECONNREFUSED); 5839 5840 return NF_ACCEPT; 5841 } 5842 5843 static unsigned int selinux_ip_postroute(void *priv, 5844 struct sk_buff *skb, 5845 const struct nf_hook_state *state) 5846 { 5847 u16 family; 5848 u32 secmark_perm; 5849 u32 peer_sid; 5850 int ifindex; 5851 struct sock *sk; 5852 struct common_audit_data ad; 5853 struct lsm_network_audit net; 5854 char *addrp; 5855 int secmark_active, peerlbl_active; 5856 5857 /* If any sort of compatibility mode is enabled then handoff processing 5858 * to the selinux_ip_postroute_compat() function to deal with the 5859 * special handling. We do this in an attempt to keep this function 5860 * as fast and as clean as possible. */ 5861 if (!selinux_policycap_netpeer()) 5862 return selinux_ip_postroute_compat(skb, state); 5863 5864 secmark_active = selinux_secmark_enabled(); 5865 peerlbl_active = selinux_peerlbl_enabled(); 5866 if (!secmark_active && !peerlbl_active) 5867 return NF_ACCEPT; 5868 5869 sk = skb_to_full_sk(skb); 5870 5871 #ifdef CONFIG_XFRM 5872 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5873 * packet transformation so allow the packet to pass without any checks 5874 * since we'll have another chance to perform access control checks 5875 * when the packet is on it's final way out. 5876 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5877 * is NULL, in this case go ahead and apply access control. 5878 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5879 * TCP listening state we cannot wait until the XFRM processing 5880 * is done as we will miss out on the SA label if we do; 5881 * unfortunately, this means more work, but it is only once per 5882 * connection. */ 5883 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5884 !(sk && sk_listener(sk))) 5885 return NF_ACCEPT; 5886 #endif 5887 5888 family = state->pf; 5889 if (sk == NULL) { 5890 /* Without an associated socket the packet is either coming 5891 * from the kernel or it is being forwarded; check the packet 5892 * to determine which and if the packet is being forwarded 5893 * query the packet directly to determine the security label. */ 5894 if (skb->skb_iif) { 5895 secmark_perm = PACKET__FORWARD_OUT; 5896 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5897 return NF_DROP; 5898 } else { 5899 secmark_perm = PACKET__SEND; 5900 peer_sid = SECINITSID_KERNEL; 5901 } 5902 } else if (sk_listener(sk)) { 5903 /* Locally generated packet but the associated socket is in the 5904 * listening state which means this is a SYN-ACK packet. In 5905 * this particular case the correct security label is assigned 5906 * to the connection/request_sock but unfortunately we can't 5907 * query the request_sock as it isn't queued on the parent 5908 * socket until after the SYN-ACK packet is sent; the only 5909 * viable choice is to regenerate the label like we do in 5910 * selinux_inet_conn_request(). See also selinux_ip_output() 5911 * for similar problems. */ 5912 u32 skb_sid; 5913 struct sk_security_struct *sksec; 5914 5915 sksec = selinux_sock(sk); 5916 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5917 return NF_DROP; 5918 /* At this point, if the returned skb peerlbl is SECSID_NULL 5919 * and the packet has been through at least one XFRM 5920 * transformation then we must be dealing with the "final" 5921 * form of labeled IPsec packet; since we've already applied 5922 * all of our access controls on this packet we can safely 5923 * pass the packet. */ 5924 if (skb_sid == SECSID_NULL) { 5925 switch (family) { 5926 case PF_INET: 5927 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5928 return NF_ACCEPT; 5929 break; 5930 case PF_INET6: 5931 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5932 return NF_ACCEPT; 5933 break; 5934 default: 5935 return NF_DROP_ERR(-ECONNREFUSED); 5936 } 5937 } 5938 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5939 return NF_DROP; 5940 secmark_perm = PACKET__SEND; 5941 } else { 5942 /* Locally generated packet, fetch the security label from the 5943 * associated socket. */ 5944 struct sk_security_struct *sksec = selinux_sock(sk); 5945 peer_sid = sksec->sid; 5946 secmark_perm = PACKET__SEND; 5947 } 5948 5949 ifindex = state->out->ifindex; 5950 ad_net_init_from_iif(&ad, &net, ifindex, family); 5951 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5952 return NF_DROP; 5953 5954 if (secmark_active) 5955 if (avc_has_perm(peer_sid, skb->secmark, 5956 SECCLASS_PACKET, secmark_perm, &ad)) 5957 return NF_DROP_ERR(-ECONNREFUSED); 5958 5959 if (peerlbl_active) { 5960 u32 if_sid; 5961 u32 node_sid; 5962 5963 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5964 return NF_DROP; 5965 if (avc_has_perm(peer_sid, if_sid, 5966 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5967 return NF_DROP_ERR(-ECONNREFUSED); 5968 5969 if (sel_netnode_sid(addrp, family, &node_sid)) 5970 return NF_DROP; 5971 if (avc_has_perm(peer_sid, node_sid, 5972 SECCLASS_NODE, NODE__SENDTO, &ad)) 5973 return NF_DROP_ERR(-ECONNREFUSED); 5974 } 5975 5976 return NF_ACCEPT; 5977 } 5978 #endif /* CONFIG_NETFILTER */ 5979 5980 static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type) 5981 { 5982 struct sk_security_struct *sksec = sk->sk_security; 5983 struct common_audit_data ad; 5984 u8 driver; 5985 u8 xperm; 5986 5987 if (sock_skip_has_perm(sksec->sid)) 5988 return 0; 5989 5990 ad.type = LSM_AUDIT_DATA_NLMSGTYPE; 5991 ad.u.nlmsg_type = nlmsg_type; 5992 5993 driver = nlmsg_type >> 8; 5994 xperm = nlmsg_type & 0xff; 5995 5996 return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass, 5997 perms, driver, AVC_EXT_NLMSG, xperm, &ad); 5998 } 5999 6000 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 6001 { 6002 int rc = 0; 6003 unsigned int msg_len; 6004 unsigned int data_len = skb->len; 6005 unsigned char *data = skb->data; 6006 struct nlmsghdr *nlh; 6007 struct sk_security_struct *sksec = selinux_sock(sk); 6008 u16 sclass = sksec->sclass; 6009 u32 perm; 6010 6011 while (data_len >= nlmsg_total_size(0)) { 6012 nlh = (struct nlmsghdr *)data; 6013 6014 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 6015 * users which means we can't reject skb's with bogus 6016 * length fields; our solution is to follow what 6017 * netlink_rcv_skb() does and simply skip processing at 6018 * messages with length fields that are clearly junk 6019 */ 6020 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 6021 return 0; 6022 6023 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 6024 if (rc == 0) { 6025 if (selinux_policycap_netlink_xperm()) { 6026 rc = nlmsg_sock_has_extended_perms( 6027 sk, perm, nlh->nlmsg_type); 6028 } else { 6029 rc = sock_has_perm(sk, perm); 6030 } 6031 if (rc) 6032 return rc; 6033 } else if (rc == -EINVAL) { 6034 /* -EINVAL is a missing msg/perm mapping */ 6035 pr_warn_ratelimited("SELinux: unrecognized netlink" 6036 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 6037 " pid=%d comm=%s\n", 6038 sk->sk_protocol, nlh->nlmsg_type, 6039 secclass_map[sclass - 1].name, 6040 task_pid_nr(current), current->comm); 6041 if (enforcing_enabled() && 6042 !security_get_allow_unknown()) 6043 return rc; 6044 rc = 0; 6045 } else if (rc == -ENOENT) { 6046 /* -ENOENT is a missing socket/class mapping, ignore */ 6047 rc = 0; 6048 } else { 6049 return rc; 6050 } 6051 6052 /* move to the next message after applying netlink padding */ 6053 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 6054 if (msg_len >= data_len) 6055 return 0; 6056 data_len -= msg_len; 6057 data += msg_len; 6058 } 6059 6060 return rc; 6061 } 6062 6063 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 6064 { 6065 isec->sclass = sclass; 6066 isec->sid = current_sid(); 6067 } 6068 6069 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 6070 u32 perms) 6071 { 6072 struct ipc_security_struct *isec; 6073 struct common_audit_data ad; 6074 u32 sid = current_sid(); 6075 6076 isec = selinux_ipc(ipc_perms); 6077 6078 ad.type = LSM_AUDIT_DATA_IPC; 6079 ad.u.ipc_id = ipc_perms->key; 6080 6081 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 6082 } 6083 6084 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 6085 { 6086 struct msg_security_struct *msec; 6087 6088 msec = selinux_msg_msg(msg); 6089 msec->sid = SECINITSID_UNLABELED; 6090 6091 return 0; 6092 } 6093 6094 /* message queue security operations */ 6095 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 6096 { 6097 struct ipc_security_struct *isec; 6098 struct common_audit_data ad; 6099 u32 sid = current_sid(); 6100 6101 isec = selinux_ipc(msq); 6102 ipc_init_security(isec, SECCLASS_MSGQ); 6103 6104 ad.type = LSM_AUDIT_DATA_IPC; 6105 ad.u.ipc_id = msq->key; 6106 6107 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6108 MSGQ__CREATE, &ad); 6109 } 6110 6111 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 6112 { 6113 struct ipc_security_struct *isec; 6114 struct common_audit_data ad; 6115 u32 sid = current_sid(); 6116 6117 isec = selinux_ipc(msq); 6118 6119 ad.type = LSM_AUDIT_DATA_IPC; 6120 ad.u.ipc_id = msq->key; 6121 6122 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6123 MSGQ__ASSOCIATE, &ad); 6124 } 6125 6126 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 6127 { 6128 u32 perms; 6129 6130 switch (cmd) { 6131 case IPC_INFO: 6132 case MSG_INFO: 6133 /* No specific object, just general system-wide information. */ 6134 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6135 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6136 case IPC_STAT: 6137 case MSG_STAT: 6138 case MSG_STAT_ANY: 6139 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6140 break; 6141 case IPC_SET: 6142 perms = MSGQ__SETATTR; 6143 break; 6144 case IPC_RMID: 6145 perms = MSGQ__DESTROY; 6146 break; 6147 default: 6148 return 0; 6149 } 6150 6151 return ipc_has_perm(msq, perms); 6152 } 6153 6154 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6155 { 6156 struct ipc_security_struct *isec; 6157 struct msg_security_struct *msec; 6158 struct common_audit_data ad; 6159 u32 sid = current_sid(); 6160 int rc; 6161 6162 isec = selinux_ipc(msq); 6163 msec = selinux_msg_msg(msg); 6164 6165 /* 6166 * First time through, need to assign label to the message 6167 */ 6168 if (msec->sid == SECINITSID_UNLABELED) { 6169 /* 6170 * Compute new sid based on current process and 6171 * message queue this message will be stored in 6172 */ 6173 rc = security_transition_sid(sid, isec->sid, 6174 SECCLASS_MSG, NULL, &msec->sid); 6175 if (rc) 6176 return rc; 6177 } 6178 6179 ad.type = LSM_AUDIT_DATA_IPC; 6180 ad.u.ipc_id = msq->key; 6181 6182 /* Can this process write to the queue? */ 6183 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6184 MSGQ__WRITE, &ad); 6185 if (!rc) 6186 /* Can this process send the message */ 6187 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6188 MSG__SEND, &ad); 6189 if (!rc) 6190 /* Can the message be put in the queue? */ 6191 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6192 MSGQ__ENQUEUE, &ad); 6193 6194 return rc; 6195 } 6196 6197 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6198 struct task_struct *target, 6199 long type, int mode) 6200 { 6201 struct ipc_security_struct *isec; 6202 struct msg_security_struct *msec; 6203 struct common_audit_data ad; 6204 u32 sid = task_sid_obj(target); 6205 int rc; 6206 6207 isec = selinux_ipc(msq); 6208 msec = selinux_msg_msg(msg); 6209 6210 ad.type = LSM_AUDIT_DATA_IPC; 6211 ad.u.ipc_id = msq->key; 6212 6213 rc = avc_has_perm(sid, isec->sid, 6214 SECCLASS_MSGQ, MSGQ__READ, &ad); 6215 if (!rc) 6216 rc = avc_has_perm(sid, msec->sid, 6217 SECCLASS_MSG, MSG__RECEIVE, &ad); 6218 return rc; 6219 } 6220 6221 /* Shared Memory security operations */ 6222 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6223 { 6224 struct ipc_security_struct *isec; 6225 struct common_audit_data ad; 6226 u32 sid = current_sid(); 6227 6228 isec = selinux_ipc(shp); 6229 ipc_init_security(isec, SECCLASS_SHM); 6230 6231 ad.type = LSM_AUDIT_DATA_IPC; 6232 ad.u.ipc_id = shp->key; 6233 6234 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6235 SHM__CREATE, &ad); 6236 } 6237 6238 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6239 { 6240 struct ipc_security_struct *isec; 6241 struct common_audit_data ad; 6242 u32 sid = current_sid(); 6243 6244 isec = selinux_ipc(shp); 6245 6246 ad.type = LSM_AUDIT_DATA_IPC; 6247 ad.u.ipc_id = shp->key; 6248 6249 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6250 SHM__ASSOCIATE, &ad); 6251 } 6252 6253 /* Note, at this point, shp is locked down */ 6254 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6255 { 6256 u32 perms; 6257 6258 switch (cmd) { 6259 case IPC_INFO: 6260 case SHM_INFO: 6261 /* No specific object, just general system-wide information. */ 6262 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6263 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6264 case IPC_STAT: 6265 case SHM_STAT: 6266 case SHM_STAT_ANY: 6267 perms = SHM__GETATTR | SHM__ASSOCIATE; 6268 break; 6269 case IPC_SET: 6270 perms = SHM__SETATTR; 6271 break; 6272 case SHM_LOCK: 6273 case SHM_UNLOCK: 6274 perms = SHM__LOCK; 6275 break; 6276 case IPC_RMID: 6277 perms = SHM__DESTROY; 6278 break; 6279 default: 6280 return 0; 6281 } 6282 6283 return ipc_has_perm(shp, perms); 6284 } 6285 6286 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6287 char __user *shmaddr, int shmflg) 6288 { 6289 u32 perms; 6290 6291 if (shmflg & SHM_RDONLY) 6292 perms = SHM__READ; 6293 else 6294 perms = SHM__READ | SHM__WRITE; 6295 6296 return ipc_has_perm(shp, perms); 6297 } 6298 6299 /* Semaphore security operations */ 6300 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6301 { 6302 struct ipc_security_struct *isec; 6303 struct common_audit_data ad; 6304 u32 sid = current_sid(); 6305 6306 isec = selinux_ipc(sma); 6307 ipc_init_security(isec, SECCLASS_SEM); 6308 6309 ad.type = LSM_AUDIT_DATA_IPC; 6310 ad.u.ipc_id = sma->key; 6311 6312 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6313 SEM__CREATE, &ad); 6314 } 6315 6316 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6317 { 6318 struct ipc_security_struct *isec; 6319 struct common_audit_data ad; 6320 u32 sid = current_sid(); 6321 6322 isec = selinux_ipc(sma); 6323 6324 ad.type = LSM_AUDIT_DATA_IPC; 6325 ad.u.ipc_id = sma->key; 6326 6327 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6328 SEM__ASSOCIATE, &ad); 6329 } 6330 6331 /* Note, at this point, sma is locked down */ 6332 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6333 { 6334 int err; 6335 u32 perms; 6336 6337 switch (cmd) { 6338 case IPC_INFO: 6339 case SEM_INFO: 6340 /* No specific object, just general system-wide information. */ 6341 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6342 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6343 case GETPID: 6344 case GETNCNT: 6345 case GETZCNT: 6346 perms = SEM__GETATTR; 6347 break; 6348 case GETVAL: 6349 case GETALL: 6350 perms = SEM__READ; 6351 break; 6352 case SETVAL: 6353 case SETALL: 6354 perms = SEM__WRITE; 6355 break; 6356 case IPC_RMID: 6357 perms = SEM__DESTROY; 6358 break; 6359 case IPC_SET: 6360 perms = SEM__SETATTR; 6361 break; 6362 case IPC_STAT: 6363 case SEM_STAT: 6364 case SEM_STAT_ANY: 6365 perms = SEM__GETATTR | SEM__ASSOCIATE; 6366 break; 6367 default: 6368 return 0; 6369 } 6370 6371 err = ipc_has_perm(sma, perms); 6372 return err; 6373 } 6374 6375 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6376 struct sembuf *sops, unsigned nsops, int alter) 6377 { 6378 u32 perms; 6379 6380 if (alter) 6381 perms = SEM__READ | SEM__WRITE; 6382 else 6383 perms = SEM__READ; 6384 6385 return ipc_has_perm(sma, perms); 6386 } 6387 6388 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6389 { 6390 u32 av = 0; 6391 6392 av = 0; 6393 if (flag & S_IRUGO) 6394 av |= IPC__UNIX_READ; 6395 if (flag & S_IWUGO) 6396 av |= IPC__UNIX_WRITE; 6397 6398 if (av == 0) 6399 return 0; 6400 6401 return ipc_has_perm(ipcp, av); 6402 } 6403 6404 static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp, 6405 struct lsm_prop *prop) 6406 { 6407 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6408 prop->selinux.secid = isec->sid; 6409 } 6410 6411 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6412 { 6413 if (inode) 6414 inode_doinit_with_dentry(inode, dentry); 6415 } 6416 6417 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p, 6418 char **value) 6419 { 6420 const struct task_security_struct *tsec; 6421 int error; 6422 u32 sid; 6423 u32 len; 6424 6425 rcu_read_lock(); 6426 tsec = selinux_cred(__task_cred(p)); 6427 if (p != current) { 6428 error = avc_has_perm(current_sid(), tsec->sid, 6429 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6430 if (error) 6431 goto err_unlock; 6432 } 6433 switch (attr) { 6434 case LSM_ATTR_CURRENT: 6435 sid = tsec->sid; 6436 break; 6437 case LSM_ATTR_PREV: 6438 sid = tsec->osid; 6439 break; 6440 case LSM_ATTR_EXEC: 6441 sid = tsec->exec_sid; 6442 break; 6443 case LSM_ATTR_FSCREATE: 6444 sid = tsec->create_sid; 6445 break; 6446 case LSM_ATTR_KEYCREATE: 6447 sid = tsec->keycreate_sid; 6448 break; 6449 case LSM_ATTR_SOCKCREATE: 6450 sid = tsec->sockcreate_sid; 6451 break; 6452 default: 6453 error = -EOPNOTSUPP; 6454 goto err_unlock; 6455 } 6456 rcu_read_unlock(); 6457 6458 if (sid == SECSID_NULL) { 6459 *value = NULL; 6460 return 0; 6461 } 6462 6463 error = security_sid_to_context(sid, value, &len); 6464 if (error) 6465 return error; 6466 return len; 6467 6468 err_unlock: 6469 rcu_read_unlock(); 6470 return error; 6471 } 6472 6473 static int selinux_lsm_setattr(u64 attr, void *value, size_t size) 6474 { 6475 struct task_security_struct *tsec; 6476 struct cred *new; 6477 u32 mysid = current_sid(), sid = 0, ptsid; 6478 int error; 6479 char *str = value; 6480 6481 /* 6482 * Basic control over ability to set these attributes at all. 6483 */ 6484 switch (attr) { 6485 case LSM_ATTR_EXEC: 6486 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6487 PROCESS__SETEXEC, NULL); 6488 break; 6489 case LSM_ATTR_FSCREATE: 6490 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6491 PROCESS__SETFSCREATE, NULL); 6492 break; 6493 case LSM_ATTR_KEYCREATE: 6494 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6495 PROCESS__SETKEYCREATE, NULL); 6496 break; 6497 case LSM_ATTR_SOCKCREATE: 6498 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6499 PROCESS__SETSOCKCREATE, NULL); 6500 break; 6501 case LSM_ATTR_CURRENT: 6502 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6503 PROCESS__SETCURRENT, NULL); 6504 break; 6505 default: 6506 error = -EOPNOTSUPP; 6507 break; 6508 } 6509 if (error) 6510 return error; 6511 6512 /* Obtain a SID for the context, if one was specified. */ 6513 if (size && str[0] && str[0] != '\n') { 6514 if (str[size-1] == '\n') { 6515 str[size-1] = 0; 6516 size--; 6517 } 6518 error = security_context_to_sid(value, size, 6519 &sid, GFP_KERNEL); 6520 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) { 6521 if (!has_cap_mac_admin(true)) { 6522 struct audit_buffer *ab; 6523 size_t audit_size; 6524 6525 /* We strip a nul only if it is at the end, 6526 * otherwise the context contains a nul and 6527 * we should audit that */ 6528 if (str[size - 1] == '\0') 6529 audit_size = size - 1; 6530 else 6531 audit_size = size; 6532 ab = audit_log_start(audit_context(), 6533 GFP_ATOMIC, 6534 AUDIT_SELINUX_ERR); 6535 if (!ab) 6536 return error; 6537 audit_log_format(ab, "op=fscreate invalid_context="); 6538 audit_log_n_untrustedstring(ab, value, 6539 audit_size); 6540 audit_log_end(ab); 6541 6542 return error; 6543 } 6544 error = security_context_to_sid_force(value, size, 6545 &sid); 6546 } 6547 if (error) 6548 return error; 6549 } 6550 6551 new = prepare_creds(); 6552 if (!new) 6553 return -ENOMEM; 6554 6555 /* Permission checking based on the specified context is 6556 performed during the actual operation (execve, 6557 open/mkdir/...), when we know the full context of the 6558 operation. See selinux_bprm_creds_for_exec for the execve 6559 checks and may_create for the file creation checks. The 6560 operation will then fail if the context is not permitted. */ 6561 tsec = selinux_cred(new); 6562 if (attr == LSM_ATTR_EXEC) { 6563 tsec->exec_sid = sid; 6564 } else if (attr == LSM_ATTR_FSCREATE) { 6565 tsec->create_sid = sid; 6566 } else if (attr == LSM_ATTR_KEYCREATE) { 6567 if (sid) { 6568 error = avc_has_perm(mysid, sid, 6569 SECCLASS_KEY, KEY__CREATE, NULL); 6570 if (error) 6571 goto abort_change; 6572 } 6573 tsec->keycreate_sid = sid; 6574 } else if (attr == LSM_ATTR_SOCKCREATE) { 6575 tsec->sockcreate_sid = sid; 6576 } else if (attr == LSM_ATTR_CURRENT) { 6577 error = -EINVAL; 6578 if (sid == 0) 6579 goto abort_change; 6580 6581 if (!current_is_single_threaded()) { 6582 error = security_bounded_transition(tsec->sid, sid); 6583 if (error) 6584 goto abort_change; 6585 } 6586 6587 /* Check permissions for the transition. */ 6588 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6589 PROCESS__DYNTRANSITION, NULL); 6590 if (error) 6591 goto abort_change; 6592 6593 /* Check for ptracing, and update the task SID if ok. 6594 Otherwise, leave SID unchanged and fail. */ 6595 ptsid = ptrace_parent_sid(); 6596 if (ptsid != 0) { 6597 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6598 PROCESS__PTRACE, NULL); 6599 if (error) 6600 goto abort_change; 6601 } 6602 6603 tsec->sid = sid; 6604 } else { 6605 error = -EINVAL; 6606 goto abort_change; 6607 } 6608 6609 commit_creds(new); 6610 return size; 6611 6612 abort_change: 6613 abort_creds(new); 6614 return error; 6615 } 6616 6617 /** 6618 * selinux_getselfattr - Get SELinux current task attributes 6619 * @attr: the requested attribute 6620 * @ctx: buffer to receive the result 6621 * @size: buffer size (input), buffer size used (output) 6622 * @flags: unused 6623 * 6624 * Fill the passed user space @ctx with the details of the requested 6625 * attribute. 6626 * 6627 * Returns the number of attributes on success, an error code otherwise. 6628 * There will only ever be one attribute. 6629 */ 6630 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, 6631 u32 *size, u32 flags) 6632 { 6633 int rc; 6634 char *val = NULL; 6635 int val_len; 6636 6637 val_len = selinux_lsm_getattr(attr, current, &val); 6638 if (val_len < 0) 6639 return val_len; 6640 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0); 6641 kfree(val); 6642 return (!rc ? 1 : rc); 6643 } 6644 6645 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx, 6646 u32 size, u32 flags) 6647 { 6648 int rc; 6649 6650 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len); 6651 if (rc > 0) 6652 return 0; 6653 return rc; 6654 } 6655 6656 static int selinux_getprocattr(struct task_struct *p, 6657 const char *name, char **value) 6658 { 6659 unsigned int attr = lsm_name_to_attr(name); 6660 int rc; 6661 6662 if (attr) { 6663 rc = selinux_lsm_getattr(attr, p, value); 6664 if (rc != -EOPNOTSUPP) 6665 return rc; 6666 } 6667 6668 return -EINVAL; 6669 } 6670 6671 static int selinux_setprocattr(const char *name, void *value, size_t size) 6672 { 6673 int attr = lsm_name_to_attr(name); 6674 6675 if (attr) 6676 return selinux_lsm_setattr(attr, value, size); 6677 return -EINVAL; 6678 } 6679 6680 static int selinux_ismaclabel(const char *name) 6681 { 6682 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6683 } 6684 6685 static int selinux_secid_to_secctx(u32 secid, struct lsm_context *cp) 6686 { 6687 u32 seclen; 6688 int ret; 6689 6690 if (cp) { 6691 cp->id = LSM_ID_SELINUX; 6692 ret = security_sid_to_context(secid, &cp->context, &cp->len); 6693 if (ret < 0) 6694 return ret; 6695 return cp->len; 6696 } 6697 ret = security_sid_to_context(secid, NULL, &seclen); 6698 if (ret < 0) 6699 return ret; 6700 return seclen; 6701 } 6702 6703 static int selinux_lsmprop_to_secctx(struct lsm_prop *prop, 6704 struct lsm_context *cp) 6705 { 6706 return selinux_secid_to_secctx(prop->selinux.secid, cp); 6707 } 6708 6709 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6710 { 6711 return security_context_to_sid(secdata, seclen, 6712 secid, GFP_KERNEL); 6713 } 6714 6715 static void selinux_release_secctx(struct lsm_context *cp) 6716 { 6717 if (cp->id == LSM_ID_SELINUX) { 6718 kfree(cp->context); 6719 cp->context = NULL; 6720 cp->id = LSM_ID_UNDEF; 6721 } 6722 } 6723 6724 static void selinux_inode_invalidate_secctx(struct inode *inode) 6725 { 6726 struct inode_security_struct *isec = selinux_inode(inode); 6727 6728 spin_lock(&isec->lock); 6729 isec->initialized = LABEL_INVALID; 6730 spin_unlock(&isec->lock); 6731 } 6732 6733 /* 6734 * called with inode->i_mutex locked 6735 */ 6736 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6737 { 6738 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6739 ctx, ctxlen, 0); 6740 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6741 return rc == -EOPNOTSUPP ? 0 : rc; 6742 } 6743 6744 /* 6745 * called with inode->i_mutex locked 6746 */ 6747 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6748 { 6749 return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6750 ctx, ctxlen, 0, NULL); 6751 } 6752 6753 static int selinux_inode_getsecctx(struct inode *inode, struct lsm_context *cp) 6754 { 6755 int len; 6756 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6757 XATTR_SELINUX_SUFFIX, 6758 (void **)&cp->context, true); 6759 if (len < 0) 6760 return len; 6761 cp->len = len; 6762 cp->id = LSM_ID_SELINUX; 6763 return 0; 6764 } 6765 #ifdef CONFIG_KEYS 6766 6767 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6768 unsigned long flags) 6769 { 6770 const struct task_security_struct *tsec; 6771 struct key_security_struct *ksec = selinux_key(k); 6772 6773 tsec = selinux_cred(cred); 6774 if (tsec->keycreate_sid) 6775 ksec->sid = tsec->keycreate_sid; 6776 else 6777 ksec->sid = tsec->sid; 6778 6779 return 0; 6780 } 6781 6782 static int selinux_key_permission(key_ref_t key_ref, 6783 const struct cred *cred, 6784 enum key_need_perm need_perm) 6785 { 6786 struct key *key; 6787 struct key_security_struct *ksec; 6788 u32 perm, sid; 6789 6790 switch (need_perm) { 6791 case KEY_NEED_VIEW: 6792 perm = KEY__VIEW; 6793 break; 6794 case KEY_NEED_READ: 6795 perm = KEY__READ; 6796 break; 6797 case KEY_NEED_WRITE: 6798 perm = KEY__WRITE; 6799 break; 6800 case KEY_NEED_SEARCH: 6801 perm = KEY__SEARCH; 6802 break; 6803 case KEY_NEED_LINK: 6804 perm = KEY__LINK; 6805 break; 6806 case KEY_NEED_SETATTR: 6807 perm = KEY__SETATTR; 6808 break; 6809 case KEY_NEED_UNLINK: 6810 case KEY_SYSADMIN_OVERRIDE: 6811 case KEY_AUTHTOKEN_OVERRIDE: 6812 case KEY_DEFER_PERM_CHECK: 6813 return 0; 6814 default: 6815 WARN_ON(1); 6816 return -EPERM; 6817 6818 } 6819 6820 sid = cred_sid(cred); 6821 key = key_ref_to_ptr(key_ref); 6822 ksec = selinux_key(key); 6823 6824 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6825 } 6826 6827 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6828 { 6829 struct key_security_struct *ksec = selinux_key(key); 6830 char *context = NULL; 6831 unsigned len; 6832 int rc; 6833 6834 rc = security_sid_to_context(ksec->sid, 6835 &context, &len); 6836 if (!rc) 6837 rc = len; 6838 *_buffer = context; 6839 return rc; 6840 } 6841 6842 #ifdef CONFIG_KEY_NOTIFICATIONS 6843 static int selinux_watch_key(struct key *key) 6844 { 6845 struct key_security_struct *ksec = selinux_key(key); 6846 u32 sid = current_sid(); 6847 6848 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6849 } 6850 #endif 6851 #endif 6852 6853 #ifdef CONFIG_SECURITY_INFINIBAND 6854 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6855 { 6856 struct common_audit_data ad; 6857 int err; 6858 u32 sid = 0; 6859 struct ib_security_struct *sec = ib_sec; 6860 struct lsm_ibpkey_audit ibpkey; 6861 6862 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6863 if (err) 6864 return err; 6865 6866 ad.type = LSM_AUDIT_DATA_IBPKEY; 6867 ibpkey.subnet_prefix = subnet_prefix; 6868 ibpkey.pkey = pkey_val; 6869 ad.u.ibpkey = &ibpkey; 6870 return avc_has_perm(sec->sid, sid, 6871 SECCLASS_INFINIBAND_PKEY, 6872 INFINIBAND_PKEY__ACCESS, &ad); 6873 } 6874 6875 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6876 u8 port_num) 6877 { 6878 struct common_audit_data ad; 6879 int err; 6880 u32 sid = 0; 6881 struct ib_security_struct *sec = ib_sec; 6882 struct lsm_ibendport_audit ibendport; 6883 6884 err = security_ib_endport_sid(dev_name, port_num, 6885 &sid); 6886 6887 if (err) 6888 return err; 6889 6890 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6891 ibendport.dev_name = dev_name; 6892 ibendport.port = port_num; 6893 ad.u.ibendport = &ibendport; 6894 return avc_has_perm(sec->sid, sid, 6895 SECCLASS_INFINIBAND_ENDPORT, 6896 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6897 } 6898 6899 static int selinux_ib_alloc_security(void *ib_sec) 6900 { 6901 struct ib_security_struct *sec = selinux_ib(ib_sec); 6902 6903 sec->sid = current_sid(); 6904 return 0; 6905 } 6906 #endif 6907 6908 #ifdef CONFIG_BPF_SYSCALL 6909 static int selinux_bpf(int cmd, union bpf_attr *attr, 6910 unsigned int size, bool kernel) 6911 { 6912 u32 sid = current_sid(); 6913 int ret; 6914 6915 switch (cmd) { 6916 case BPF_MAP_CREATE: 6917 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6918 NULL); 6919 break; 6920 case BPF_PROG_LOAD: 6921 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6922 NULL); 6923 break; 6924 default: 6925 ret = 0; 6926 break; 6927 } 6928 6929 return ret; 6930 } 6931 6932 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6933 { 6934 u32 av = 0; 6935 6936 if (fmode & FMODE_READ) 6937 av |= BPF__MAP_READ; 6938 if (fmode & FMODE_WRITE) 6939 av |= BPF__MAP_WRITE; 6940 return av; 6941 } 6942 6943 /* This function will check the file pass through unix socket or binder to see 6944 * if it is a bpf related object. And apply corresponding checks on the bpf 6945 * object based on the type. The bpf maps and programs, not like other files and 6946 * socket, are using a shared anonymous inode inside the kernel as their inode. 6947 * So checking that inode cannot identify if the process have privilege to 6948 * access the bpf object and that's why we have to add this additional check in 6949 * selinux_file_receive and selinux_binder_transfer_files. 6950 */ 6951 static int bpf_fd_pass(const struct file *file, u32 sid) 6952 { 6953 struct bpf_security_struct *bpfsec; 6954 struct bpf_prog *prog; 6955 struct bpf_map *map; 6956 int ret; 6957 6958 if (file->f_op == &bpf_map_fops) { 6959 map = file->private_data; 6960 bpfsec = map->security; 6961 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6962 bpf_map_fmode_to_av(file->f_mode), NULL); 6963 if (ret) 6964 return ret; 6965 } else if (file->f_op == &bpf_prog_fops) { 6966 prog = file->private_data; 6967 bpfsec = prog->aux->security; 6968 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6969 BPF__PROG_RUN, NULL); 6970 if (ret) 6971 return ret; 6972 } 6973 return 0; 6974 } 6975 6976 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6977 { 6978 u32 sid = current_sid(); 6979 struct bpf_security_struct *bpfsec; 6980 6981 bpfsec = map->security; 6982 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6983 bpf_map_fmode_to_av(fmode), NULL); 6984 } 6985 6986 static int selinux_bpf_prog(struct bpf_prog *prog) 6987 { 6988 u32 sid = current_sid(); 6989 struct bpf_security_struct *bpfsec; 6990 6991 bpfsec = prog->aux->security; 6992 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6993 BPF__PROG_RUN, NULL); 6994 } 6995 6996 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 6997 struct bpf_token *token, bool kernel) 6998 { 6999 struct bpf_security_struct *bpfsec; 7000 7001 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 7002 if (!bpfsec) 7003 return -ENOMEM; 7004 7005 bpfsec->sid = current_sid(); 7006 map->security = bpfsec; 7007 7008 return 0; 7009 } 7010 7011 static void selinux_bpf_map_free(struct bpf_map *map) 7012 { 7013 struct bpf_security_struct *bpfsec = map->security; 7014 7015 map->security = NULL; 7016 kfree(bpfsec); 7017 } 7018 7019 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 7020 struct bpf_token *token, bool kernel) 7021 { 7022 struct bpf_security_struct *bpfsec; 7023 7024 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 7025 if (!bpfsec) 7026 return -ENOMEM; 7027 7028 bpfsec->sid = current_sid(); 7029 prog->aux->security = bpfsec; 7030 7031 return 0; 7032 } 7033 7034 static void selinux_bpf_prog_free(struct bpf_prog *prog) 7035 { 7036 struct bpf_security_struct *bpfsec = prog->aux->security; 7037 7038 prog->aux->security = NULL; 7039 kfree(bpfsec); 7040 } 7041 7042 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 7043 const struct path *path) 7044 { 7045 struct bpf_security_struct *bpfsec; 7046 7047 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 7048 if (!bpfsec) 7049 return -ENOMEM; 7050 7051 bpfsec->sid = current_sid(); 7052 token->security = bpfsec; 7053 7054 return 0; 7055 } 7056 7057 static void selinux_bpf_token_free(struct bpf_token *token) 7058 { 7059 struct bpf_security_struct *bpfsec = token->security; 7060 7061 token->security = NULL; 7062 kfree(bpfsec); 7063 } 7064 #endif 7065 7066 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 7067 .lbs_cred = sizeof(struct task_security_struct), 7068 .lbs_file = sizeof(struct file_security_struct), 7069 .lbs_inode = sizeof(struct inode_security_struct), 7070 .lbs_ipc = sizeof(struct ipc_security_struct), 7071 .lbs_key = sizeof(struct key_security_struct), 7072 .lbs_msg_msg = sizeof(struct msg_security_struct), 7073 #ifdef CONFIG_PERF_EVENTS 7074 .lbs_perf_event = sizeof(struct perf_event_security_struct), 7075 #endif 7076 .lbs_sock = sizeof(struct sk_security_struct), 7077 .lbs_superblock = sizeof(struct superblock_security_struct), 7078 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 7079 .lbs_tun_dev = sizeof(struct tun_security_struct), 7080 .lbs_ib = sizeof(struct ib_security_struct), 7081 }; 7082 7083 #ifdef CONFIG_PERF_EVENTS 7084 static int selinux_perf_event_open(int type) 7085 { 7086 u32 requested, sid = current_sid(); 7087 7088 if (type == PERF_SECURITY_OPEN) 7089 requested = PERF_EVENT__OPEN; 7090 else if (type == PERF_SECURITY_CPU) 7091 requested = PERF_EVENT__CPU; 7092 else if (type == PERF_SECURITY_KERNEL) 7093 requested = PERF_EVENT__KERNEL; 7094 else if (type == PERF_SECURITY_TRACEPOINT) 7095 requested = PERF_EVENT__TRACEPOINT; 7096 else 7097 return -EINVAL; 7098 7099 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 7100 requested, NULL); 7101 } 7102 7103 static int selinux_perf_event_alloc(struct perf_event *event) 7104 { 7105 struct perf_event_security_struct *perfsec; 7106 7107 perfsec = selinux_perf_event(event->security); 7108 perfsec->sid = current_sid(); 7109 7110 return 0; 7111 } 7112 7113 static int selinux_perf_event_read(struct perf_event *event) 7114 { 7115 struct perf_event_security_struct *perfsec = event->security; 7116 u32 sid = current_sid(); 7117 7118 return avc_has_perm(sid, perfsec->sid, 7119 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 7120 } 7121 7122 static int selinux_perf_event_write(struct perf_event *event) 7123 { 7124 struct perf_event_security_struct *perfsec = event->security; 7125 u32 sid = current_sid(); 7126 7127 return avc_has_perm(sid, perfsec->sid, 7128 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 7129 } 7130 #endif 7131 7132 #ifdef CONFIG_IO_URING 7133 /** 7134 * selinux_uring_override_creds - check the requested cred override 7135 * @new: the target creds 7136 * 7137 * Check to see if the current task is allowed to override it's credentials 7138 * to service an io_uring operation. 7139 */ 7140 static int selinux_uring_override_creds(const struct cred *new) 7141 { 7142 return avc_has_perm(current_sid(), cred_sid(new), 7143 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 7144 } 7145 7146 /** 7147 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 7148 * 7149 * Check to see if the current task is allowed to create a new io_uring 7150 * kernel polling thread. 7151 */ 7152 static int selinux_uring_sqpoll(void) 7153 { 7154 u32 sid = current_sid(); 7155 7156 return avc_has_perm(sid, sid, 7157 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 7158 } 7159 7160 /** 7161 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 7162 * @ioucmd: the io_uring command structure 7163 * 7164 * Check to see if the current domain is allowed to execute an 7165 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 7166 * 7167 */ 7168 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 7169 { 7170 struct file *file = ioucmd->file; 7171 struct inode *inode = file_inode(file); 7172 struct inode_security_struct *isec = selinux_inode(inode); 7173 struct common_audit_data ad; 7174 7175 ad.type = LSM_AUDIT_DATA_FILE; 7176 ad.u.file = file; 7177 7178 return avc_has_perm(current_sid(), isec->sid, 7179 SECCLASS_IO_URING, IO_URING__CMD, &ad); 7180 } 7181 7182 /** 7183 * selinux_uring_allowed - check if io_uring_setup() can be called 7184 * 7185 * Check to see if the current task is allowed to call io_uring_setup(). 7186 */ 7187 static int selinux_uring_allowed(void) 7188 { 7189 u32 sid = current_sid(); 7190 7191 return avc_has_perm(sid, sid, SECCLASS_IO_URING, IO_URING__ALLOWED, 7192 NULL); 7193 } 7194 #endif /* CONFIG_IO_URING */ 7195 7196 static const struct lsm_id selinux_lsmid = { 7197 .name = "selinux", 7198 .id = LSM_ID_SELINUX, 7199 }; 7200 7201 /* 7202 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 7203 * 1. any hooks that don't belong to (2.) or (3.) below, 7204 * 2. hooks that both access structures allocated by other hooks, and allocate 7205 * structures that can be later accessed by other hooks (mostly "cloning" 7206 * hooks), 7207 * 3. hooks that only allocate structures that can be later accessed by other 7208 * hooks ("allocating" hooks). 7209 * 7210 * Please follow block comment delimiters in the list to keep this order. 7211 */ 7212 static struct security_hook_list selinux_hooks[] __ro_after_init = { 7213 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 7214 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 7215 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 7216 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 7217 7218 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 7219 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 7220 LSM_HOOK_INIT(capget, selinux_capget), 7221 LSM_HOOK_INIT(capset, selinux_capset), 7222 LSM_HOOK_INIT(capable, selinux_capable), 7223 LSM_HOOK_INIT(quotactl, selinux_quotactl), 7224 LSM_HOOK_INIT(quota_on, selinux_quota_on), 7225 LSM_HOOK_INIT(syslog, selinux_syslog), 7226 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 7227 7228 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 7229 7230 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 7231 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 7232 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 7233 7234 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 7235 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 7236 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 7237 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 7238 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 7239 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 7240 LSM_HOOK_INIT(sb_mount, selinux_mount), 7241 LSM_HOOK_INIT(sb_umount, selinux_umount), 7242 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7243 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7244 7245 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7246 7247 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7248 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7249 7250 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7251 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7252 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7253 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7254 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7255 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7256 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7257 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7258 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7259 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7260 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7261 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7262 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7263 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7264 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7265 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7266 LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap), 7267 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7268 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7269 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7270 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7271 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7272 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7273 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7274 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7275 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7276 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7277 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7278 LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop), 7279 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7280 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7281 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7282 7283 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7284 7285 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7286 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7287 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7288 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat), 7289 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7290 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7291 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7292 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7293 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7294 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7295 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7296 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7297 7298 LSM_HOOK_INIT(file_open, selinux_file_open), 7299 7300 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7301 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7302 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7303 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7304 LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop), 7305 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7306 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7307 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7308 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7309 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7310 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7311 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7312 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7313 LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj), 7314 LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj), 7315 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7316 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7317 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7318 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7319 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7320 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7321 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7322 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7323 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7324 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7325 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7326 7327 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7328 LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop), 7329 7330 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7331 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7332 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7333 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7334 7335 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7336 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7337 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7338 7339 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7340 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7341 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7342 7343 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7344 7345 LSM_HOOK_INIT(getselfattr, selinux_getselfattr), 7346 LSM_HOOK_INIT(setselfattr, selinux_setselfattr), 7347 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7348 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7349 7350 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7351 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7352 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7353 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7354 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7355 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7356 7357 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7358 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7359 7360 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7361 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7362 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7363 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7364 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7365 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7366 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7367 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7368 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7369 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7370 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7371 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7372 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7373 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7374 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7375 LSM_HOOK_INIT(socket_getpeersec_stream, 7376 selinux_socket_getpeersec_stream), 7377 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7378 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7379 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7380 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7381 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7382 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7383 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7384 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7385 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7386 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7387 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7388 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7389 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7390 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7391 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7392 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7393 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7394 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7395 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7396 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7397 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7398 #ifdef CONFIG_SECURITY_INFINIBAND 7399 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7400 LSM_HOOK_INIT(ib_endport_manage_subnet, 7401 selinux_ib_endport_manage_subnet), 7402 #endif 7403 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7404 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7405 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7406 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7407 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7408 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7409 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7410 selinux_xfrm_state_pol_flow_match), 7411 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7412 #endif 7413 7414 #ifdef CONFIG_KEYS 7415 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7416 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7417 #ifdef CONFIG_KEY_NOTIFICATIONS 7418 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7419 #endif 7420 #endif 7421 7422 #ifdef CONFIG_AUDIT 7423 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7424 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7425 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7426 #endif 7427 7428 #ifdef CONFIG_BPF_SYSCALL 7429 LSM_HOOK_INIT(bpf, selinux_bpf), 7430 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7431 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7432 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free), 7433 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free), 7434 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free), 7435 #endif 7436 7437 #ifdef CONFIG_PERF_EVENTS 7438 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7439 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7440 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7441 #endif 7442 7443 #ifdef CONFIG_IO_URING 7444 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7445 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7446 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7447 LSM_HOOK_INIT(uring_allowed, selinux_uring_allowed), 7448 #endif 7449 7450 /* 7451 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7452 */ 7453 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7454 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7455 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7456 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7457 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7458 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7459 #endif 7460 7461 /* 7462 * PUT "ALLOCATING" HOOKS HERE 7463 */ 7464 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7465 LSM_HOOK_INIT(msg_queue_alloc_security, 7466 selinux_msg_queue_alloc_security), 7467 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7468 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7469 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7470 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7471 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7472 LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx), 7473 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7474 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7475 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7476 #ifdef CONFIG_SECURITY_INFINIBAND 7477 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7478 #endif 7479 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7480 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7481 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7482 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7483 selinux_xfrm_state_alloc_acquire), 7484 #endif 7485 #ifdef CONFIG_KEYS 7486 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7487 #endif 7488 #ifdef CONFIG_AUDIT 7489 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7490 #endif 7491 #ifdef CONFIG_BPF_SYSCALL 7492 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create), 7493 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load), 7494 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create), 7495 #endif 7496 #ifdef CONFIG_PERF_EVENTS 7497 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7498 #endif 7499 }; 7500 7501 static __init int selinux_init(void) 7502 { 7503 pr_info("SELinux: Initializing.\n"); 7504 7505 memset(&selinux_state, 0, sizeof(selinux_state)); 7506 enforcing_set(selinux_enforcing_boot); 7507 selinux_avc_init(); 7508 mutex_init(&selinux_state.status_lock); 7509 mutex_init(&selinux_state.policy_mutex); 7510 7511 /* Set the security state for the initial task. */ 7512 cred_init_security(); 7513 7514 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7515 if (!default_noexec) 7516 pr_notice("SELinux: virtual memory is executable by default\n"); 7517 7518 avc_init(); 7519 7520 avtab_cache_init(); 7521 7522 ebitmap_cache_init(); 7523 7524 hashtab_cache_init(); 7525 7526 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), 7527 &selinux_lsmid); 7528 7529 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7530 panic("SELinux: Unable to register AVC netcache callback\n"); 7531 7532 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7533 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7534 7535 if (selinux_enforcing_boot) 7536 pr_debug("SELinux: Starting in enforcing mode\n"); 7537 else 7538 pr_debug("SELinux: Starting in permissive mode\n"); 7539 7540 fs_validate_description("selinux", selinux_fs_parameters); 7541 7542 return 0; 7543 } 7544 7545 static void delayed_superblock_init(struct super_block *sb, void *unused) 7546 { 7547 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7548 } 7549 7550 void selinux_complete_init(void) 7551 { 7552 pr_debug("SELinux: Completing initialization.\n"); 7553 7554 /* Set up any superblocks initialized prior to the policy load. */ 7555 pr_debug("SELinux: Setting up existing superblocks.\n"); 7556 iterate_supers(delayed_superblock_init, NULL); 7557 } 7558 7559 /* SELinux requires early initialization in order to label 7560 all processes and objects when they are created. */ 7561 DEFINE_LSM(selinux) = { 7562 .name = "selinux", 7563 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7564 .enabled = &selinux_enabled_boot, 7565 .blobs = &selinux_blob_sizes, 7566 .init = selinux_init, 7567 }; 7568 7569 #if defined(CONFIG_NETFILTER) 7570 static const struct nf_hook_ops selinux_nf_ops[] = { 7571 { 7572 .hook = selinux_ip_postroute, 7573 .pf = NFPROTO_IPV4, 7574 .hooknum = NF_INET_POST_ROUTING, 7575 .priority = NF_IP_PRI_SELINUX_LAST, 7576 }, 7577 { 7578 .hook = selinux_ip_forward, 7579 .pf = NFPROTO_IPV4, 7580 .hooknum = NF_INET_FORWARD, 7581 .priority = NF_IP_PRI_SELINUX_FIRST, 7582 }, 7583 { 7584 .hook = selinux_ip_output, 7585 .pf = NFPROTO_IPV4, 7586 .hooknum = NF_INET_LOCAL_OUT, 7587 .priority = NF_IP_PRI_SELINUX_FIRST, 7588 }, 7589 #if IS_ENABLED(CONFIG_IPV6) 7590 { 7591 .hook = selinux_ip_postroute, 7592 .pf = NFPROTO_IPV6, 7593 .hooknum = NF_INET_POST_ROUTING, 7594 .priority = NF_IP6_PRI_SELINUX_LAST, 7595 }, 7596 { 7597 .hook = selinux_ip_forward, 7598 .pf = NFPROTO_IPV6, 7599 .hooknum = NF_INET_FORWARD, 7600 .priority = NF_IP6_PRI_SELINUX_FIRST, 7601 }, 7602 { 7603 .hook = selinux_ip_output, 7604 .pf = NFPROTO_IPV6, 7605 .hooknum = NF_INET_LOCAL_OUT, 7606 .priority = NF_IP6_PRI_SELINUX_FIRST, 7607 }, 7608 #endif /* IPV6 */ 7609 }; 7610 7611 static int __net_init selinux_nf_register(struct net *net) 7612 { 7613 return nf_register_net_hooks(net, selinux_nf_ops, 7614 ARRAY_SIZE(selinux_nf_ops)); 7615 } 7616 7617 static void __net_exit selinux_nf_unregister(struct net *net) 7618 { 7619 nf_unregister_net_hooks(net, selinux_nf_ops, 7620 ARRAY_SIZE(selinux_nf_ops)); 7621 } 7622 7623 static struct pernet_operations selinux_net_ops = { 7624 .init = selinux_nf_register, 7625 .exit = selinux_nf_unregister, 7626 }; 7627 7628 static int __init selinux_nf_ip_init(void) 7629 { 7630 int err; 7631 7632 if (!selinux_enabled_boot) 7633 return 0; 7634 7635 pr_debug("SELinux: Registering netfilter hooks\n"); 7636 7637 err = register_pernet_subsys(&selinux_net_ops); 7638 if (err) 7639 panic("SELinux: register_pernet_subsys: error %d\n", err); 7640 7641 return 0; 7642 } 7643 __initcall(selinux_nf_ip_init); 7644 #endif /* CONFIG_NETFILTER */ 7645