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_module_from_file(struct file *file) 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 /* init_module */ 4111 if (file == NULL) 4112 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 4113 SYSTEM__MODULE_LOAD, NULL); 4114 4115 /* finit_module */ 4116 4117 ad.type = LSM_AUDIT_DATA_FILE; 4118 ad.u.file = file; 4119 4120 fsec = selinux_file(file); 4121 if (sid != fsec->sid) { 4122 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4123 if (rc) 4124 return rc; 4125 } 4126 4127 isec = inode_security(file_inode(file)); 4128 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 4129 SYSTEM__MODULE_LOAD, &ad); 4130 } 4131 4132 static int selinux_kernel_read_file(struct file *file, 4133 enum kernel_read_file_id id, 4134 bool contents) 4135 { 4136 int rc = 0; 4137 4138 switch (id) { 4139 case READING_MODULE: 4140 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4141 break; 4142 default: 4143 break; 4144 } 4145 4146 return rc; 4147 } 4148 4149 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4150 { 4151 int rc = 0; 4152 4153 switch (id) { 4154 case LOADING_MODULE: 4155 rc = selinux_kernel_module_from_file(NULL); 4156 break; 4157 default: 4158 break; 4159 } 4160 4161 return rc; 4162 } 4163 4164 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4165 { 4166 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4167 PROCESS__SETPGID, NULL); 4168 } 4169 4170 static int selinux_task_getpgid(struct task_struct *p) 4171 { 4172 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4173 PROCESS__GETPGID, NULL); 4174 } 4175 4176 static int selinux_task_getsid(struct task_struct *p) 4177 { 4178 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4179 PROCESS__GETSESSION, NULL); 4180 } 4181 4182 static void selinux_current_getlsmprop_subj(struct lsm_prop *prop) 4183 { 4184 prop->selinux.secid = current_sid(); 4185 } 4186 4187 static void selinux_task_getlsmprop_obj(struct task_struct *p, 4188 struct lsm_prop *prop) 4189 { 4190 prop->selinux.secid = task_sid_obj(p); 4191 } 4192 4193 static int selinux_task_setnice(struct task_struct *p, int nice) 4194 { 4195 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4196 PROCESS__SETSCHED, NULL); 4197 } 4198 4199 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4200 { 4201 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4202 PROCESS__SETSCHED, NULL); 4203 } 4204 4205 static int selinux_task_getioprio(struct task_struct *p) 4206 { 4207 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4208 PROCESS__GETSCHED, NULL); 4209 } 4210 4211 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4212 unsigned int flags) 4213 { 4214 u32 av = 0; 4215 4216 if (!flags) 4217 return 0; 4218 if (flags & LSM_PRLIMIT_WRITE) 4219 av |= PROCESS__SETRLIMIT; 4220 if (flags & LSM_PRLIMIT_READ) 4221 av |= PROCESS__GETRLIMIT; 4222 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4223 SECCLASS_PROCESS, av, NULL); 4224 } 4225 4226 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4227 struct rlimit *new_rlim) 4228 { 4229 struct rlimit *old_rlim = p->signal->rlim + resource; 4230 4231 /* Control the ability to change the hard limit (whether 4232 lowering or raising it), so that the hard limit can 4233 later be used as a safe reset point for the soft limit 4234 upon context transitions. See selinux_bprm_committing_creds. */ 4235 if (old_rlim->rlim_max != new_rlim->rlim_max) 4236 return avc_has_perm(current_sid(), task_sid_obj(p), 4237 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4238 4239 return 0; 4240 } 4241 4242 static int selinux_task_setscheduler(struct task_struct *p) 4243 { 4244 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4245 PROCESS__SETSCHED, NULL); 4246 } 4247 4248 static int selinux_task_getscheduler(struct task_struct *p) 4249 { 4250 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4251 PROCESS__GETSCHED, NULL); 4252 } 4253 4254 static int selinux_task_movememory(struct task_struct *p) 4255 { 4256 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4257 PROCESS__SETSCHED, NULL); 4258 } 4259 4260 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4261 int sig, const struct cred *cred) 4262 { 4263 u32 secid; 4264 u32 perm; 4265 4266 if (!sig) 4267 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4268 else 4269 perm = signal_to_av(sig); 4270 if (!cred) 4271 secid = current_sid(); 4272 else 4273 secid = cred_sid(cred); 4274 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4275 } 4276 4277 static void selinux_task_to_inode(struct task_struct *p, 4278 struct inode *inode) 4279 { 4280 struct inode_security_struct *isec = selinux_inode(inode); 4281 u32 sid = task_sid_obj(p); 4282 4283 spin_lock(&isec->lock); 4284 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4285 isec->sid = sid; 4286 isec->initialized = LABEL_INITIALIZED; 4287 spin_unlock(&isec->lock); 4288 } 4289 4290 static int selinux_userns_create(const struct cred *cred) 4291 { 4292 u32 sid = current_sid(); 4293 4294 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4295 USER_NAMESPACE__CREATE, NULL); 4296 } 4297 4298 /* Returns error only if unable to parse addresses */ 4299 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4300 struct common_audit_data *ad, u8 *proto) 4301 { 4302 int offset, ihlen, ret = -EINVAL; 4303 struct iphdr _iph, *ih; 4304 4305 offset = skb_network_offset(skb); 4306 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4307 if (ih == NULL) 4308 goto out; 4309 4310 ihlen = ih->ihl * 4; 4311 if (ihlen < sizeof(_iph)) 4312 goto out; 4313 4314 ad->u.net->v4info.saddr = ih->saddr; 4315 ad->u.net->v4info.daddr = ih->daddr; 4316 ret = 0; 4317 4318 if (proto) 4319 *proto = ih->protocol; 4320 4321 switch (ih->protocol) { 4322 case IPPROTO_TCP: { 4323 struct tcphdr _tcph, *th; 4324 4325 if (ntohs(ih->frag_off) & IP_OFFSET) 4326 break; 4327 4328 offset += ihlen; 4329 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4330 if (th == NULL) 4331 break; 4332 4333 ad->u.net->sport = th->source; 4334 ad->u.net->dport = th->dest; 4335 break; 4336 } 4337 4338 case IPPROTO_UDP: { 4339 struct udphdr _udph, *uh; 4340 4341 if (ntohs(ih->frag_off) & IP_OFFSET) 4342 break; 4343 4344 offset += ihlen; 4345 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4346 if (uh == NULL) 4347 break; 4348 4349 ad->u.net->sport = uh->source; 4350 ad->u.net->dport = uh->dest; 4351 break; 4352 } 4353 4354 case IPPROTO_DCCP: { 4355 struct dccp_hdr _dccph, *dh; 4356 4357 if (ntohs(ih->frag_off) & IP_OFFSET) 4358 break; 4359 4360 offset += ihlen; 4361 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4362 if (dh == NULL) 4363 break; 4364 4365 ad->u.net->sport = dh->dccph_sport; 4366 ad->u.net->dport = dh->dccph_dport; 4367 break; 4368 } 4369 4370 #if IS_ENABLED(CONFIG_IP_SCTP) 4371 case IPPROTO_SCTP: { 4372 struct sctphdr _sctph, *sh; 4373 4374 if (ntohs(ih->frag_off) & IP_OFFSET) 4375 break; 4376 4377 offset += ihlen; 4378 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4379 if (sh == NULL) 4380 break; 4381 4382 ad->u.net->sport = sh->source; 4383 ad->u.net->dport = sh->dest; 4384 break; 4385 } 4386 #endif 4387 default: 4388 break; 4389 } 4390 out: 4391 return ret; 4392 } 4393 4394 #if IS_ENABLED(CONFIG_IPV6) 4395 4396 /* Returns error only if unable to parse addresses */ 4397 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4398 struct common_audit_data *ad, u8 *proto) 4399 { 4400 u8 nexthdr; 4401 int ret = -EINVAL, offset; 4402 struct ipv6hdr _ipv6h, *ip6; 4403 __be16 frag_off; 4404 4405 offset = skb_network_offset(skb); 4406 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4407 if (ip6 == NULL) 4408 goto out; 4409 4410 ad->u.net->v6info.saddr = ip6->saddr; 4411 ad->u.net->v6info.daddr = ip6->daddr; 4412 ret = 0; 4413 4414 nexthdr = ip6->nexthdr; 4415 offset += sizeof(_ipv6h); 4416 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4417 if (offset < 0) 4418 goto out; 4419 4420 if (proto) 4421 *proto = nexthdr; 4422 4423 switch (nexthdr) { 4424 case IPPROTO_TCP: { 4425 struct tcphdr _tcph, *th; 4426 4427 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4428 if (th == NULL) 4429 break; 4430 4431 ad->u.net->sport = th->source; 4432 ad->u.net->dport = th->dest; 4433 break; 4434 } 4435 4436 case IPPROTO_UDP: { 4437 struct udphdr _udph, *uh; 4438 4439 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4440 if (uh == NULL) 4441 break; 4442 4443 ad->u.net->sport = uh->source; 4444 ad->u.net->dport = uh->dest; 4445 break; 4446 } 4447 4448 case IPPROTO_DCCP: { 4449 struct dccp_hdr _dccph, *dh; 4450 4451 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4452 if (dh == NULL) 4453 break; 4454 4455 ad->u.net->sport = dh->dccph_sport; 4456 ad->u.net->dport = dh->dccph_dport; 4457 break; 4458 } 4459 4460 #if IS_ENABLED(CONFIG_IP_SCTP) 4461 case IPPROTO_SCTP: { 4462 struct sctphdr _sctph, *sh; 4463 4464 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4465 if (sh == NULL) 4466 break; 4467 4468 ad->u.net->sport = sh->source; 4469 ad->u.net->dport = sh->dest; 4470 break; 4471 } 4472 #endif 4473 /* includes fragments */ 4474 default: 4475 break; 4476 } 4477 out: 4478 return ret; 4479 } 4480 4481 #endif /* IPV6 */ 4482 4483 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4484 char **_addrp, int src, u8 *proto) 4485 { 4486 char *addrp; 4487 int ret; 4488 4489 switch (ad->u.net->family) { 4490 case PF_INET: 4491 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4492 if (ret) 4493 goto parse_error; 4494 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4495 &ad->u.net->v4info.daddr); 4496 goto okay; 4497 4498 #if IS_ENABLED(CONFIG_IPV6) 4499 case PF_INET6: 4500 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4501 if (ret) 4502 goto parse_error; 4503 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4504 &ad->u.net->v6info.daddr); 4505 goto okay; 4506 #endif /* IPV6 */ 4507 default: 4508 addrp = NULL; 4509 goto okay; 4510 } 4511 4512 parse_error: 4513 pr_warn( 4514 "SELinux: failure in selinux_parse_skb()," 4515 " unable to parse packet\n"); 4516 return ret; 4517 4518 okay: 4519 if (_addrp) 4520 *_addrp = addrp; 4521 return 0; 4522 } 4523 4524 /** 4525 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4526 * @skb: the packet 4527 * @family: protocol family 4528 * @sid: the packet's peer label SID 4529 * 4530 * Description: 4531 * Check the various different forms of network peer labeling and determine 4532 * the peer label/SID for the packet; most of the magic actually occurs in 4533 * the security server function security_net_peersid_cmp(). The function 4534 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4535 * or -EACCES if @sid is invalid due to inconsistencies with the different 4536 * peer labels. 4537 * 4538 */ 4539 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4540 { 4541 int err; 4542 u32 xfrm_sid; 4543 u32 nlbl_sid; 4544 u32 nlbl_type; 4545 4546 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4547 if (unlikely(err)) 4548 return -EACCES; 4549 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4550 if (unlikely(err)) 4551 return -EACCES; 4552 4553 err = security_net_peersid_resolve(nlbl_sid, 4554 nlbl_type, xfrm_sid, sid); 4555 if (unlikely(err)) { 4556 pr_warn( 4557 "SELinux: failure in selinux_skb_peerlbl_sid()," 4558 " unable to determine packet's peer label\n"); 4559 return -EACCES; 4560 } 4561 4562 return 0; 4563 } 4564 4565 /** 4566 * selinux_conn_sid - Determine the child socket label for a connection 4567 * @sk_sid: the parent socket's SID 4568 * @skb_sid: the packet's SID 4569 * @conn_sid: the resulting connection SID 4570 * 4571 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4572 * combined with the MLS information from @skb_sid in order to create 4573 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4574 * of @sk_sid. Returns zero on success, negative values on failure. 4575 * 4576 */ 4577 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4578 { 4579 int err = 0; 4580 4581 if (skb_sid != SECSID_NULL) 4582 err = security_sid_mls_copy(sk_sid, skb_sid, 4583 conn_sid); 4584 else 4585 *conn_sid = sk_sid; 4586 4587 return err; 4588 } 4589 4590 /* socket security operations */ 4591 4592 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4593 u16 secclass, u32 *socksid) 4594 { 4595 if (tsec->sockcreate_sid > SECSID_NULL) { 4596 *socksid = tsec->sockcreate_sid; 4597 return 0; 4598 } 4599 4600 return security_transition_sid(tsec->sid, tsec->sid, 4601 secclass, NULL, socksid); 4602 } 4603 4604 static bool sock_skip_has_perm(u32 sid) 4605 { 4606 if (sid == SECINITSID_KERNEL) 4607 return true; 4608 4609 /* 4610 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that 4611 * inherited the kernel context from early boot used to be skipped 4612 * here, so preserve that behavior unless the capability is set. 4613 * 4614 * By setting the capability the policy signals that it is ready 4615 * for this quirk to be fixed. Note that sockets created by a kernel 4616 * thread or a usermode helper executed without a transition will 4617 * still be skipped in this check regardless of the policycap 4618 * setting. 4619 */ 4620 if (!selinux_policycap_userspace_initial_context() && 4621 sid == SECINITSID_INIT) 4622 return true; 4623 return false; 4624 } 4625 4626 4627 static int sock_has_perm(struct sock *sk, u32 perms) 4628 { 4629 struct sk_security_struct *sksec = sk->sk_security; 4630 struct common_audit_data ad; 4631 struct lsm_network_audit net; 4632 4633 if (sock_skip_has_perm(sksec->sid)) 4634 return 0; 4635 4636 ad_net_init_from_sk(&ad, &net, sk); 4637 4638 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4639 &ad); 4640 } 4641 4642 static int selinux_socket_create(int family, int type, 4643 int protocol, int kern) 4644 { 4645 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4646 u32 newsid; 4647 u16 secclass; 4648 int rc; 4649 4650 if (kern) 4651 return 0; 4652 4653 secclass = socket_type_to_security_class(family, type, protocol); 4654 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4655 if (rc) 4656 return rc; 4657 4658 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4659 } 4660 4661 static int selinux_socket_post_create(struct socket *sock, int family, 4662 int type, int protocol, int kern) 4663 { 4664 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4665 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4666 struct sk_security_struct *sksec; 4667 u16 sclass = socket_type_to_security_class(family, type, protocol); 4668 u32 sid = SECINITSID_KERNEL; 4669 int err = 0; 4670 4671 if (!kern) { 4672 err = socket_sockcreate_sid(tsec, sclass, &sid); 4673 if (err) 4674 return err; 4675 } 4676 4677 isec->sclass = sclass; 4678 isec->sid = sid; 4679 isec->initialized = LABEL_INITIALIZED; 4680 4681 if (sock->sk) { 4682 sksec = selinux_sock(sock->sk); 4683 sksec->sclass = sclass; 4684 sksec->sid = sid; 4685 /* Allows detection of the first association on this socket */ 4686 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4687 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4688 4689 err = selinux_netlbl_socket_post_create(sock->sk, family); 4690 } 4691 4692 return err; 4693 } 4694 4695 static int selinux_socket_socketpair(struct socket *socka, 4696 struct socket *sockb) 4697 { 4698 struct sk_security_struct *sksec_a = selinux_sock(socka->sk); 4699 struct sk_security_struct *sksec_b = selinux_sock(sockb->sk); 4700 4701 sksec_a->peer_sid = sksec_b->sid; 4702 sksec_b->peer_sid = sksec_a->sid; 4703 4704 return 0; 4705 } 4706 4707 /* Range of port numbers used to automatically bind. 4708 Need to determine whether we should perform a name_bind 4709 permission check between the socket and the port number. */ 4710 4711 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4712 { 4713 struct sock *sk = sock->sk; 4714 struct sk_security_struct *sksec = selinux_sock(sk); 4715 u16 family; 4716 int err; 4717 4718 err = sock_has_perm(sk, SOCKET__BIND); 4719 if (err) 4720 goto out; 4721 4722 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4723 family = sk->sk_family; 4724 if (family == PF_INET || family == PF_INET6) { 4725 char *addrp; 4726 struct common_audit_data ad; 4727 struct lsm_network_audit net = {0,}; 4728 struct sockaddr_in *addr4 = NULL; 4729 struct sockaddr_in6 *addr6 = NULL; 4730 u16 family_sa; 4731 unsigned short snum; 4732 u32 sid, node_perm; 4733 4734 /* 4735 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4736 * that validates multiple binding addresses. Because of this 4737 * need to check address->sa_family as it is possible to have 4738 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4739 */ 4740 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4741 return -EINVAL; 4742 family_sa = address->sa_family; 4743 switch (family_sa) { 4744 case AF_UNSPEC: 4745 case AF_INET: 4746 if (addrlen < sizeof(struct sockaddr_in)) 4747 return -EINVAL; 4748 addr4 = (struct sockaddr_in *)address; 4749 if (family_sa == AF_UNSPEC) { 4750 if (family == PF_INET6) { 4751 /* Length check from inet6_bind_sk() */ 4752 if (addrlen < SIN6_LEN_RFC2133) 4753 return -EINVAL; 4754 /* Family check from __inet6_bind() */ 4755 goto err_af; 4756 } 4757 /* see __inet_bind(), we only want to allow 4758 * AF_UNSPEC if the address is INADDR_ANY 4759 */ 4760 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4761 goto err_af; 4762 family_sa = AF_INET; 4763 } 4764 snum = ntohs(addr4->sin_port); 4765 addrp = (char *)&addr4->sin_addr.s_addr; 4766 break; 4767 case AF_INET6: 4768 if (addrlen < SIN6_LEN_RFC2133) 4769 return -EINVAL; 4770 addr6 = (struct sockaddr_in6 *)address; 4771 snum = ntohs(addr6->sin6_port); 4772 addrp = (char *)&addr6->sin6_addr.s6_addr; 4773 break; 4774 default: 4775 goto err_af; 4776 } 4777 4778 ad.type = LSM_AUDIT_DATA_NET; 4779 ad.u.net = &net; 4780 ad.u.net->sport = htons(snum); 4781 ad.u.net->family = family_sa; 4782 4783 if (snum) { 4784 int low, high; 4785 4786 inet_get_local_port_range(sock_net(sk), &low, &high); 4787 4788 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4789 snum < low || snum > high) { 4790 err = sel_netport_sid(sk->sk_protocol, 4791 snum, &sid); 4792 if (err) 4793 goto out; 4794 err = avc_has_perm(sksec->sid, sid, 4795 sksec->sclass, 4796 SOCKET__NAME_BIND, &ad); 4797 if (err) 4798 goto out; 4799 } 4800 } 4801 4802 switch (sksec->sclass) { 4803 case SECCLASS_TCP_SOCKET: 4804 node_perm = TCP_SOCKET__NODE_BIND; 4805 break; 4806 4807 case SECCLASS_UDP_SOCKET: 4808 node_perm = UDP_SOCKET__NODE_BIND; 4809 break; 4810 4811 case SECCLASS_DCCP_SOCKET: 4812 node_perm = DCCP_SOCKET__NODE_BIND; 4813 break; 4814 4815 case SECCLASS_SCTP_SOCKET: 4816 node_perm = SCTP_SOCKET__NODE_BIND; 4817 break; 4818 4819 default: 4820 node_perm = RAWIP_SOCKET__NODE_BIND; 4821 break; 4822 } 4823 4824 err = sel_netnode_sid(addrp, family_sa, &sid); 4825 if (err) 4826 goto out; 4827 4828 if (family_sa == AF_INET) 4829 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4830 else 4831 ad.u.net->v6info.saddr = addr6->sin6_addr; 4832 4833 err = avc_has_perm(sksec->sid, sid, 4834 sksec->sclass, node_perm, &ad); 4835 if (err) 4836 goto out; 4837 } 4838 out: 4839 return err; 4840 err_af: 4841 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4842 if (sk->sk_protocol == IPPROTO_SCTP) 4843 return -EINVAL; 4844 return -EAFNOSUPPORT; 4845 } 4846 4847 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4848 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4849 */ 4850 static int selinux_socket_connect_helper(struct socket *sock, 4851 struct sockaddr *address, int addrlen) 4852 { 4853 struct sock *sk = sock->sk; 4854 struct sk_security_struct *sksec = selinux_sock(sk); 4855 int err; 4856 4857 err = sock_has_perm(sk, SOCKET__CONNECT); 4858 if (err) 4859 return err; 4860 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4861 return -EINVAL; 4862 4863 /* connect(AF_UNSPEC) has special handling, as it is a documented 4864 * way to disconnect the socket 4865 */ 4866 if (address->sa_family == AF_UNSPEC) 4867 return 0; 4868 4869 /* 4870 * If a TCP, DCCP or SCTP socket, check name_connect permission 4871 * for the port. 4872 */ 4873 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4874 sksec->sclass == SECCLASS_DCCP_SOCKET || 4875 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4876 struct common_audit_data ad; 4877 struct lsm_network_audit net = {0,}; 4878 struct sockaddr_in *addr4 = NULL; 4879 struct sockaddr_in6 *addr6 = NULL; 4880 unsigned short snum; 4881 u32 sid, perm; 4882 4883 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4884 * that validates multiple connect addresses. Because of this 4885 * need to check address->sa_family as it is possible to have 4886 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4887 */ 4888 switch (address->sa_family) { 4889 case AF_INET: 4890 addr4 = (struct sockaddr_in *)address; 4891 if (addrlen < sizeof(struct sockaddr_in)) 4892 return -EINVAL; 4893 snum = ntohs(addr4->sin_port); 4894 break; 4895 case AF_INET6: 4896 addr6 = (struct sockaddr_in6 *)address; 4897 if (addrlen < SIN6_LEN_RFC2133) 4898 return -EINVAL; 4899 snum = ntohs(addr6->sin6_port); 4900 break; 4901 default: 4902 /* Note that SCTP services expect -EINVAL, whereas 4903 * others expect -EAFNOSUPPORT. 4904 */ 4905 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4906 return -EINVAL; 4907 else 4908 return -EAFNOSUPPORT; 4909 } 4910 4911 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4912 if (err) 4913 return err; 4914 4915 switch (sksec->sclass) { 4916 case SECCLASS_TCP_SOCKET: 4917 perm = TCP_SOCKET__NAME_CONNECT; 4918 break; 4919 case SECCLASS_DCCP_SOCKET: 4920 perm = DCCP_SOCKET__NAME_CONNECT; 4921 break; 4922 case SECCLASS_SCTP_SOCKET: 4923 perm = SCTP_SOCKET__NAME_CONNECT; 4924 break; 4925 } 4926 4927 ad.type = LSM_AUDIT_DATA_NET; 4928 ad.u.net = &net; 4929 ad.u.net->dport = htons(snum); 4930 ad.u.net->family = address->sa_family; 4931 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4932 if (err) 4933 return err; 4934 } 4935 4936 return 0; 4937 } 4938 4939 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4940 static int selinux_socket_connect(struct socket *sock, 4941 struct sockaddr *address, int addrlen) 4942 { 4943 int err; 4944 struct sock *sk = sock->sk; 4945 4946 err = selinux_socket_connect_helper(sock, address, addrlen); 4947 if (err) 4948 return err; 4949 4950 return selinux_netlbl_socket_connect(sk, address); 4951 } 4952 4953 static int selinux_socket_listen(struct socket *sock, int backlog) 4954 { 4955 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4956 } 4957 4958 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4959 { 4960 int err; 4961 struct inode_security_struct *isec; 4962 struct inode_security_struct *newisec; 4963 u16 sclass; 4964 u32 sid; 4965 4966 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4967 if (err) 4968 return err; 4969 4970 isec = inode_security_novalidate(SOCK_INODE(sock)); 4971 spin_lock(&isec->lock); 4972 sclass = isec->sclass; 4973 sid = isec->sid; 4974 spin_unlock(&isec->lock); 4975 4976 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4977 newisec->sclass = sclass; 4978 newisec->sid = sid; 4979 newisec->initialized = LABEL_INITIALIZED; 4980 4981 return 0; 4982 } 4983 4984 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4985 int size) 4986 { 4987 return sock_has_perm(sock->sk, SOCKET__WRITE); 4988 } 4989 4990 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4991 int size, int flags) 4992 { 4993 return sock_has_perm(sock->sk, SOCKET__READ); 4994 } 4995 4996 static int selinux_socket_getsockname(struct socket *sock) 4997 { 4998 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4999 } 5000 5001 static int selinux_socket_getpeername(struct socket *sock) 5002 { 5003 return sock_has_perm(sock->sk, SOCKET__GETATTR); 5004 } 5005 5006 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 5007 { 5008 int err; 5009 5010 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 5011 if (err) 5012 return err; 5013 5014 return selinux_netlbl_socket_setsockopt(sock, level, optname); 5015 } 5016 5017 static int selinux_socket_getsockopt(struct socket *sock, int level, 5018 int optname) 5019 { 5020 return sock_has_perm(sock->sk, SOCKET__GETOPT); 5021 } 5022 5023 static int selinux_socket_shutdown(struct socket *sock, int how) 5024 { 5025 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 5026 } 5027 5028 static int selinux_socket_unix_stream_connect(struct sock *sock, 5029 struct sock *other, 5030 struct sock *newsk) 5031 { 5032 struct sk_security_struct *sksec_sock = selinux_sock(sock); 5033 struct sk_security_struct *sksec_other = selinux_sock(other); 5034 struct sk_security_struct *sksec_new = selinux_sock(newsk); 5035 struct common_audit_data ad; 5036 struct lsm_network_audit net; 5037 int err; 5038 5039 ad_net_init_from_sk(&ad, &net, other); 5040 5041 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 5042 sksec_other->sclass, 5043 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 5044 if (err) 5045 return err; 5046 5047 /* server child socket */ 5048 sksec_new->peer_sid = sksec_sock->sid; 5049 err = security_sid_mls_copy(sksec_other->sid, 5050 sksec_sock->sid, &sksec_new->sid); 5051 if (err) 5052 return err; 5053 5054 /* connecting socket */ 5055 sksec_sock->peer_sid = sksec_new->sid; 5056 5057 return 0; 5058 } 5059 5060 static int selinux_socket_unix_may_send(struct socket *sock, 5061 struct socket *other) 5062 { 5063 struct sk_security_struct *ssec = selinux_sock(sock->sk); 5064 struct sk_security_struct *osec = selinux_sock(other->sk); 5065 struct common_audit_data ad; 5066 struct lsm_network_audit net; 5067 5068 ad_net_init_from_sk(&ad, &net, other->sk); 5069 5070 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 5071 &ad); 5072 } 5073 5074 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 5075 char *addrp, u16 family, u32 peer_sid, 5076 struct common_audit_data *ad) 5077 { 5078 int err; 5079 u32 if_sid; 5080 u32 node_sid; 5081 5082 err = sel_netif_sid(ns, ifindex, &if_sid); 5083 if (err) 5084 return err; 5085 err = avc_has_perm(peer_sid, if_sid, 5086 SECCLASS_NETIF, NETIF__INGRESS, ad); 5087 if (err) 5088 return err; 5089 5090 err = sel_netnode_sid(addrp, family, &node_sid); 5091 if (err) 5092 return err; 5093 return avc_has_perm(peer_sid, node_sid, 5094 SECCLASS_NODE, NODE__RECVFROM, ad); 5095 } 5096 5097 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5098 u16 family) 5099 { 5100 int err = 0; 5101 struct sk_security_struct *sksec = selinux_sock(sk); 5102 u32 sk_sid = sksec->sid; 5103 struct common_audit_data ad; 5104 struct lsm_network_audit net; 5105 char *addrp; 5106 5107 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5108 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5109 if (err) 5110 return err; 5111 5112 if (selinux_secmark_enabled()) { 5113 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5114 PACKET__RECV, &ad); 5115 if (err) 5116 return err; 5117 } 5118 5119 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5120 if (err) 5121 return err; 5122 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5123 5124 return err; 5125 } 5126 5127 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5128 { 5129 int err, peerlbl_active, secmark_active; 5130 struct sk_security_struct *sksec = selinux_sock(sk); 5131 u16 family = sk->sk_family; 5132 u32 sk_sid = sksec->sid; 5133 struct common_audit_data ad; 5134 struct lsm_network_audit net; 5135 char *addrp; 5136 5137 if (family != PF_INET && family != PF_INET6) 5138 return 0; 5139 5140 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5141 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5142 family = PF_INET; 5143 5144 /* If any sort of compatibility mode is enabled then handoff processing 5145 * to the selinux_sock_rcv_skb_compat() function to deal with the 5146 * special handling. We do this in an attempt to keep this function 5147 * as fast and as clean as possible. */ 5148 if (!selinux_policycap_netpeer()) 5149 return selinux_sock_rcv_skb_compat(sk, skb, family); 5150 5151 secmark_active = selinux_secmark_enabled(); 5152 peerlbl_active = selinux_peerlbl_enabled(); 5153 if (!secmark_active && !peerlbl_active) 5154 return 0; 5155 5156 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5157 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5158 if (err) 5159 return err; 5160 5161 if (peerlbl_active) { 5162 u32 peer_sid; 5163 5164 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5165 if (err) 5166 return err; 5167 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5168 addrp, family, peer_sid, &ad); 5169 if (err) { 5170 selinux_netlbl_err(skb, family, err, 0); 5171 return err; 5172 } 5173 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5174 PEER__RECV, &ad); 5175 if (err) { 5176 selinux_netlbl_err(skb, family, err, 0); 5177 return err; 5178 } 5179 } 5180 5181 if (secmark_active) { 5182 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5183 PACKET__RECV, &ad); 5184 if (err) 5185 return err; 5186 } 5187 5188 return err; 5189 } 5190 5191 static int selinux_socket_getpeersec_stream(struct socket *sock, 5192 sockptr_t optval, sockptr_t optlen, 5193 unsigned int len) 5194 { 5195 int err = 0; 5196 char *scontext = NULL; 5197 u32 scontext_len; 5198 struct sk_security_struct *sksec = selinux_sock(sock->sk); 5199 u32 peer_sid = SECSID_NULL; 5200 5201 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5202 sksec->sclass == SECCLASS_TCP_SOCKET || 5203 sksec->sclass == SECCLASS_SCTP_SOCKET) 5204 peer_sid = sksec->peer_sid; 5205 if (peer_sid == SECSID_NULL) 5206 return -ENOPROTOOPT; 5207 5208 err = security_sid_to_context(peer_sid, &scontext, 5209 &scontext_len); 5210 if (err) 5211 return err; 5212 if (scontext_len > len) { 5213 err = -ERANGE; 5214 goto out_len; 5215 } 5216 5217 if (copy_to_sockptr(optval, scontext, scontext_len)) 5218 err = -EFAULT; 5219 out_len: 5220 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5221 err = -EFAULT; 5222 kfree(scontext); 5223 return err; 5224 } 5225 5226 static int selinux_socket_getpeersec_dgram(struct socket *sock, 5227 struct sk_buff *skb, u32 *secid) 5228 { 5229 u32 peer_secid = SECSID_NULL; 5230 u16 family; 5231 5232 if (skb && skb->protocol == htons(ETH_P_IP)) 5233 family = PF_INET; 5234 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5235 family = PF_INET6; 5236 else if (sock) 5237 family = sock->sk->sk_family; 5238 else { 5239 *secid = SECSID_NULL; 5240 return -EINVAL; 5241 } 5242 5243 if (sock && family == PF_UNIX) { 5244 struct inode_security_struct *isec; 5245 isec = inode_security_novalidate(SOCK_INODE(sock)); 5246 peer_secid = isec->sid; 5247 } else if (skb) 5248 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5249 5250 *secid = peer_secid; 5251 if (peer_secid == SECSID_NULL) 5252 return -ENOPROTOOPT; 5253 return 0; 5254 } 5255 5256 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5257 { 5258 struct sk_security_struct *sksec = selinux_sock(sk); 5259 5260 sksec->peer_sid = SECINITSID_UNLABELED; 5261 sksec->sid = SECINITSID_UNLABELED; 5262 sksec->sclass = SECCLASS_SOCKET; 5263 selinux_netlbl_sk_security_reset(sksec); 5264 5265 return 0; 5266 } 5267 5268 static void selinux_sk_free_security(struct sock *sk) 5269 { 5270 struct sk_security_struct *sksec = selinux_sock(sk); 5271 5272 selinux_netlbl_sk_security_free(sksec); 5273 } 5274 5275 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5276 { 5277 struct sk_security_struct *sksec = selinux_sock(sk); 5278 struct sk_security_struct *newsksec = selinux_sock(newsk); 5279 5280 newsksec->sid = sksec->sid; 5281 newsksec->peer_sid = sksec->peer_sid; 5282 newsksec->sclass = sksec->sclass; 5283 5284 selinux_netlbl_sk_security_reset(newsksec); 5285 } 5286 5287 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5288 { 5289 if (!sk) 5290 *secid = SECINITSID_ANY_SOCKET; 5291 else { 5292 const struct sk_security_struct *sksec = selinux_sock(sk); 5293 5294 *secid = sksec->sid; 5295 } 5296 } 5297 5298 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5299 { 5300 struct inode_security_struct *isec = 5301 inode_security_novalidate(SOCK_INODE(parent)); 5302 struct sk_security_struct *sksec = selinux_sock(sk); 5303 5304 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5305 sk->sk_family == PF_UNIX) 5306 isec->sid = sksec->sid; 5307 sksec->sclass = isec->sclass; 5308 } 5309 5310 /* 5311 * Determines peer_secid for the asoc and updates socket's peer label 5312 * if it's the first association on the socket. 5313 */ 5314 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5315 struct sk_buff *skb) 5316 { 5317 struct sock *sk = asoc->base.sk; 5318 u16 family = sk->sk_family; 5319 struct sk_security_struct *sksec = selinux_sock(sk); 5320 struct common_audit_data ad; 5321 struct lsm_network_audit net; 5322 int err; 5323 5324 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5325 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5326 family = PF_INET; 5327 5328 if (selinux_peerlbl_enabled()) { 5329 asoc->peer_secid = SECSID_NULL; 5330 5331 /* This will return peer_sid = SECSID_NULL if there are 5332 * no peer labels, see security_net_peersid_resolve(). 5333 */ 5334 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5335 if (err) 5336 return err; 5337 5338 if (asoc->peer_secid == SECSID_NULL) 5339 asoc->peer_secid = SECINITSID_UNLABELED; 5340 } else { 5341 asoc->peer_secid = SECINITSID_UNLABELED; 5342 } 5343 5344 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5345 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5346 5347 /* Here as first association on socket. As the peer SID 5348 * was allowed by peer recv (and the netif/node checks), 5349 * then it is approved by policy and used as the primary 5350 * peer SID for getpeercon(3). 5351 */ 5352 sksec->peer_sid = asoc->peer_secid; 5353 } else if (sksec->peer_sid != asoc->peer_secid) { 5354 /* Other association peer SIDs are checked to enforce 5355 * consistency among the peer SIDs. 5356 */ 5357 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5358 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5359 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5360 &ad); 5361 if (err) 5362 return err; 5363 } 5364 return 0; 5365 } 5366 5367 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5368 * happens on an incoming connect(2), sctp_connectx(3) or 5369 * sctp_sendmsg(3) (with no association already present). 5370 */ 5371 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5372 struct sk_buff *skb) 5373 { 5374 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk); 5375 u32 conn_sid; 5376 int err; 5377 5378 if (!selinux_policycap_extsockclass()) 5379 return 0; 5380 5381 err = selinux_sctp_process_new_assoc(asoc, skb); 5382 if (err) 5383 return err; 5384 5385 /* Compute the MLS component for the connection and store 5386 * the information in asoc. This will be used by SCTP TCP type 5387 * sockets and peeled off connections as they cause a new 5388 * socket to be generated. selinux_sctp_sk_clone() will then 5389 * plug this into the new socket. 5390 */ 5391 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5392 if (err) 5393 return err; 5394 5395 asoc->secid = conn_sid; 5396 5397 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5398 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5399 } 5400 5401 /* Called when SCTP receives a COOKIE ACK chunk as the final 5402 * response to an association request (initited by us). 5403 */ 5404 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5405 struct sk_buff *skb) 5406 { 5407 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk); 5408 5409 if (!selinux_policycap_extsockclass()) 5410 return 0; 5411 5412 /* Inherit secid from the parent socket - this will be picked up 5413 * by selinux_sctp_sk_clone() if the association gets peeled off 5414 * into a new socket. 5415 */ 5416 asoc->secid = sksec->sid; 5417 5418 return selinux_sctp_process_new_assoc(asoc, skb); 5419 } 5420 5421 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5422 * based on their @optname. 5423 */ 5424 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5425 struct sockaddr *address, 5426 int addrlen) 5427 { 5428 int len, err = 0, walk_size = 0; 5429 void *addr_buf; 5430 struct sockaddr *addr; 5431 struct socket *sock; 5432 5433 if (!selinux_policycap_extsockclass()) 5434 return 0; 5435 5436 /* Process one or more addresses that may be IPv4 or IPv6 */ 5437 sock = sk->sk_socket; 5438 addr_buf = address; 5439 5440 while (walk_size < addrlen) { 5441 if (walk_size + sizeof(sa_family_t) > addrlen) 5442 return -EINVAL; 5443 5444 addr = addr_buf; 5445 switch (addr->sa_family) { 5446 case AF_UNSPEC: 5447 case AF_INET: 5448 len = sizeof(struct sockaddr_in); 5449 break; 5450 case AF_INET6: 5451 len = sizeof(struct sockaddr_in6); 5452 break; 5453 default: 5454 return -EINVAL; 5455 } 5456 5457 if (walk_size + len > addrlen) 5458 return -EINVAL; 5459 5460 err = -EINVAL; 5461 switch (optname) { 5462 /* Bind checks */ 5463 case SCTP_PRIMARY_ADDR: 5464 case SCTP_SET_PEER_PRIMARY_ADDR: 5465 case SCTP_SOCKOPT_BINDX_ADD: 5466 err = selinux_socket_bind(sock, addr, len); 5467 break; 5468 /* Connect checks */ 5469 case SCTP_SOCKOPT_CONNECTX: 5470 case SCTP_PARAM_SET_PRIMARY: 5471 case SCTP_PARAM_ADD_IP: 5472 case SCTP_SENDMSG_CONNECT: 5473 err = selinux_socket_connect_helper(sock, addr, len); 5474 if (err) 5475 return err; 5476 5477 /* As selinux_sctp_bind_connect() is called by the 5478 * SCTP protocol layer, the socket is already locked, 5479 * therefore selinux_netlbl_socket_connect_locked() 5480 * is called here. The situations handled are: 5481 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5482 * whenever a new IP address is added or when a new 5483 * primary address is selected. 5484 * Note that an SCTP connect(2) call happens before 5485 * the SCTP protocol layer and is handled via 5486 * selinux_socket_connect(). 5487 */ 5488 err = selinux_netlbl_socket_connect_locked(sk, addr); 5489 break; 5490 } 5491 5492 if (err) 5493 return err; 5494 5495 addr_buf += len; 5496 walk_size += len; 5497 } 5498 5499 return 0; 5500 } 5501 5502 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5503 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5504 struct sock *newsk) 5505 { 5506 struct sk_security_struct *sksec = selinux_sock(sk); 5507 struct sk_security_struct *newsksec = selinux_sock(newsk); 5508 5509 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5510 * the non-sctp clone version. 5511 */ 5512 if (!selinux_policycap_extsockclass()) 5513 return selinux_sk_clone_security(sk, newsk); 5514 5515 newsksec->sid = asoc->secid; 5516 newsksec->peer_sid = asoc->peer_secid; 5517 newsksec->sclass = sksec->sclass; 5518 selinux_netlbl_sctp_sk_clone(sk, newsk); 5519 } 5520 5521 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5522 { 5523 struct sk_security_struct *ssksec = selinux_sock(ssk); 5524 struct sk_security_struct *sksec = selinux_sock(sk); 5525 5526 ssksec->sclass = sksec->sclass; 5527 ssksec->sid = sksec->sid; 5528 5529 /* replace the existing subflow label deleting the existing one 5530 * and re-recreating a new label using the updated context 5531 */ 5532 selinux_netlbl_sk_security_free(ssksec); 5533 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5534 } 5535 5536 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5537 struct request_sock *req) 5538 { 5539 struct sk_security_struct *sksec = selinux_sock(sk); 5540 int err; 5541 u16 family = req->rsk_ops->family; 5542 u32 connsid; 5543 u32 peersid; 5544 5545 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5546 if (err) 5547 return err; 5548 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5549 if (err) 5550 return err; 5551 req->secid = connsid; 5552 req->peer_secid = peersid; 5553 5554 return selinux_netlbl_inet_conn_request(req, family); 5555 } 5556 5557 static void selinux_inet_csk_clone(struct sock *newsk, 5558 const struct request_sock *req) 5559 { 5560 struct sk_security_struct *newsksec = selinux_sock(newsk); 5561 5562 newsksec->sid = req->secid; 5563 newsksec->peer_sid = req->peer_secid; 5564 /* NOTE: Ideally, we should also get the isec->sid for the 5565 new socket in sync, but we don't have the isec available yet. 5566 So we will wait until sock_graft to do it, by which 5567 time it will have been created and available. */ 5568 5569 /* We don't need to take any sort of lock here as we are the only 5570 * thread with access to newsksec */ 5571 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5572 } 5573 5574 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5575 { 5576 u16 family = sk->sk_family; 5577 struct sk_security_struct *sksec = selinux_sock(sk); 5578 5579 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5580 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5581 family = PF_INET; 5582 5583 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5584 } 5585 5586 static int selinux_secmark_relabel_packet(u32 sid) 5587 { 5588 return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO, 5589 NULL); 5590 } 5591 5592 static void selinux_secmark_refcount_inc(void) 5593 { 5594 atomic_inc(&selinux_secmark_refcount); 5595 } 5596 5597 static void selinux_secmark_refcount_dec(void) 5598 { 5599 atomic_dec(&selinux_secmark_refcount); 5600 } 5601 5602 static void selinux_req_classify_flow(const struct request_sock *req, 5603 struct flowi_common *flic) 5604 { 5605 flic->flowic_secid = req->secid; 5606 } 5607 5608 static int selinux_tun_dev_alloc_security(void *security) 5609 { 5610 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5611 5612 tunsec->sid = current_sid(); 5613 return 0; 5614 } 5615 5616 static int selinux_tun_dev_create(void) 5617 { 5618 u32 sid = current_sid(); 5619 5620 /* we aren't taking into account the "sockcreate" SID since the socket 5621 * that is being created here is not a socket in the traditional sense, 5622 * instead it is a private sock, accessible only to the kernel, and 5623 * representing a wide range of network traffic spanning multiple 5624 * connections unlike traditional sockets - check the TUN driver to 5625 * get a better understanding of why this socket is special */ 5626 5627 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5628 NULL); 5629 } 5630 5631 static int selinux_tun_dev_attach_queue(void *security) 5632 { 5633 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5634 5635 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5636 TUN_SOCKET__ATTACH_QUEUE, NULL); 5637 } 5638 5639 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5640 { 5641 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5642 struct sk_security_struct *sksec = selinux_sock(sk); 5643 5644 /* we don't currently perform any NetLabel based labeling here and it 5645 * isn't clear that we would want to do so anyway; while we could apply 5646 * labeling without the support of the TUN user the resulting labeled 5647 * traffic from the other end of the connection would almost certainly 5648 * cause confusion to the TUN user that had no idea network labeling 5649 * protocols were being used */ 5650 5651 sksec->sid = tunsec->sid; 5652 sksec->sclass = SECCLASS_TUN_SOCKET; 5653 5654 return 0; 5655 } 5656 5657 static int selinux_tun_dev_open(void *security) 5658 { 5659 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5660 u32 sid = current_sid(); 5661 int err; 5662 5663 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5664 TUN_SOCKET__RELABELFROM, NULL); 5665 if (err) 5666 return err; 5667 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5668 TUN_SOCKET__RELABELTO, NULL); 5669 if (err) 5670 return err; 5671 tunsec->sid = sid; 5672 5673 return 0; 5674 } 5675 5676 #ifdef CONFIG_NETFILTER 5677 5678 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5679 const struct nf_hook_state *state) 5680 { 5681 int ifindex; 5682 u16 family; 5683 char *addrp; 5684 u32 peer_sid; 5685 struct common_audit_data ad; 5686 struct lsm_network_audit net; 5687 int secmark_active, peerlbl_active; 5688 5689 if (!selinux_policycap_netpeer()) 5690 return NF_ACCEPT; 5691 5692 secmark_active = selinux_secmark_enabled(); 5693 peerlbl_active = selinux_peerlbl_enabled(); 5694 if (!secmark_active && !peerlbl_active) 5695 return NF_ACCEPT; 5696 5697 family = state->pf; 5698 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5699 return NF_DROP; 5700 5701 ifindex = state->in->ifindex; 5702 ad_net_init_from_iif(&ad, &net, ifindex, family); 5703 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5704 return NF_DROP; 5705 5706 if (peerlbl_active) { 5707 int err; 5708 5709 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5710 addrp, family, peer_sid, &ad); 5711 if (err) { 5712 selinux_netlbl_err(skb, family, err, 1); 5713 return NF_DROP; 5714 } 5715 } 5716 5717 if (secmark_active) 5718 if (avc_has_perm(peer_sid, skb->secmark, 5719 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5720 return NF_DROP; 5721 5722 if (netlbl_enabled()) 5723 /* we do this in the FORWARD path and not the POST_ROUTING 5724 * path because we want to make sure we apply the necessary 5725 * labeling before IPsec is applied so we can leverage AH 5726 * protection */ 5727 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5728 return NF_DROP; 5729 5730 return NF_ACCEPT; 5731 } 5732 5733 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5734 const struct nf_hook_state *state) 5735 { 5736 struct sock *sk; 5737 u32 sid; 5738 5739 if (!netlbl_enabled()) 5740 return NF_ACCEPT; 5741 5742 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5743 * because we want to make sure we apply the necessary labeling 5744 * before IPsec is applied so we can leverage AH protection */ 5745 sk = sk_to_full_sk(skb->sk); 5746 if (sk) { 5747 struct sk_security_struct *sksec; 5748 5749 if (sk_listener(sk)) 5750 /* if the socket is the listening state then this 5751 * packet is a SYN-ACK packet which means it needs to 5752 * be labeled based on the connection/request_sock and 5753 * not the parent socket. unfortunately, we can't 5754 * lookup the request_sock yet as it isn't queued on 5755 * the parent socket until after the SYN-ACK is sent. 5756 * the "solution" is to simply pass the packet as-is 5757 * as any IP option based labeling should be copied 5758 * from the initial connection request (in the IP 5759 * layer). it is far from ideal, but until we get a 5760 * security label in the packet itself this is the 5761 * best we can do. */ 5762 return NF_ACCEPT; 5763 5764 /* standard practice, label using the parent socket */ 5765 sksec = selinux_sock(sk); 5766 sid = sksec->sid; 5767 } else 5768 sid = SECINITSID_KERNEL; 5769 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5770 return NF_DROP; 5771 5772 return NF_ACCEPT; 5773 } 5774 5775 5776 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5777 const struct nf_hook_state *state) 5778 { 5779 struct sock *sk; 5780 struct sk_security_struct *sksec; 5781 struct common_audit_data ad; 5782 struct lsm_network_audit net; 5783 u8 proto = 0; 5784 5785 sk = skb_to_full_sk(skb); 5786 if (sk == NULL) 5787 return NF_ACCEPT; 5788 sksec = selinux_sock(sk); 5789 5790 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5791 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5792 return NF_DROP; 5793 5794 if (selinux_secmark_enabled()) 5795 if (avc_has_perm(sksec->sid, skb->secmark, 5796 SECCLASS_PACKET, PACKET__SEND, &ad)) 5797 return NF_DROP_ERR(-ECONNREFUSED); 5798 5799 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5800 return NF_DROP_ERR(-ECONNREFUSED); 5801 5802 return NF_ACCEPT; 5803 } 5804 5805 static unsigned int selinux_ip_postroute(void *priv, 5806 struct sk_buff *skb, 5807 const struct nf_hook_state *state) 5808 { 5809 u16 family; 5810 u32 secmark_perm; 5811 u32 peer_sid; 5812 int ifindex; 5813 struct sock *sk; 5814 struct common_audit_data ad; 5815 struct lsm_network_audit net; 5816 char *addrp; 5817 int secmark_active, peerlbl_active; 5818 5819 /* If any sort of compatibility mode is enabled then handoff processing 5820 * to the selinux_ip_postroute_compat() function to deal with the 5821 * special handling. We do this in an attempt to keep this function 5822 * as fast and as clean as possible. */ 5823 if (!selinux_policycap_netpeer()) 5824 return selinux_ip_postroute_compat(skb, state); 5825 5826 secmark_active = selinux_secmark_enabled(); 5827 peerlbl_active = selinux_peerlbl_enabled(); 5828 if (!secmark_active && !peerlbl_active) 5829 return NF_ACCEPT; 5830 5831 sk = skb_to_full_sk(skb); 5832 5833 #ifdef CONFIG_XFRM 5834 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5835 * packet transformation so allow the packet to pass without any checks 5836 * since we'll have another chance to perform access control checks 5837 * when the packet is on it's final way out. 5838 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5839 * is NULL, in this case go ahead and apply access control. 5840 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5841 * TCP listening state we cannot wait until the XFRM processing 5842 * is done as we will miss out on the SA label if we do; 5843 * unfortunately, this means more work, but it is only once per 5844 * connection. */ 5845 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5846 !(sk && sk_listener(sk))) 5847 return NF_ACCEPT; 5848 #endif 5849 5850 family = state->pf; 5851 if (sk == NULL) { 5852 /* Without an associated socket the packet is either coming 5853 * from the kernel or it is being forwarded; check the packet 5854 * to determine which and if the packet is being forwarded 5855 * query the packet directly to determine the security label. */ 5856 if (skb->skb_iif) { 5857 secmark_perm = PACKET__FORWARD_OUT; 5858 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5859 return NF_DROP; 5860 } else { 5861 secmark_perm = PACKET__SEND; 5862 peer_sid = SECINITSID_KERNEL; 5863 } 5864 } else if (sk_listener(sk)) { 5865 /* Locally generated packet but the associated socket is in the 5866 * listening state which means this is a SYN-ACK packet. In 5867 * this particular case the correct security label is assigned 5868 * to the connection/request_sock but unfortunately we can't 5869 * query the request_sock as it isn't queued on the parent 5870 * socket until after the SYN-ACK packet is sent; the only 5871 * viable choice is to regenerate the label like we do in 5872 * selinux_inet_conn_request(). See also selinux_ip_output() 5873 * for similar problems. */ 5874 u32 skb_sid; 5875 struct sk_security_struct *sksec; 5876 5877 sksec = selinux_sock(sk); 5878 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5879 return NF_DROP; 5880 /* At this point, if the returned skb peerlbl is SECSID_NULL 5881 * and the packet has been through at least one XFRM 5882 * transformation then we must be dealing with the "final" 5883 * form of labeled IPsec packet; since we've already applied 5884 * all of our access controls on this packet we can safely 5885 * pass the packet. */ 5886 if (skb_sid == SECSID_NULL) { 5887 switch (family) { 5888 case PF_INET: 5889 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5890 return NF_ACCEPT; 5891 break; 5892 case PF_INET6: 5893 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5894 return NF_ACCEPT; 5895 break; 5896 default: 5897 return NF_DROP_ERR(-ECONNREFUSED); 5898 } 5899 } 5900 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5901 return NF_DROP; 5902 secmark_perm = PACKET__SEND; 5903 } else { 5904 /* Locally generated packet, fetch the security label from the 5905 * associated socket. */ 5906 struct sk_security_struct *sksec = selinux_sock(sk); 5907 peer_sid = sksec->sid; 5908 secmark_perm = PACKET__SEND; 5909 } 5910 5911 ifindex = state->out->ifindex; 5912 ad_net_init_from_iif(&ad, &net, ifindex, family); 5913 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5914 return NF_DROP; 5915 5916 if (secmark_active) 5917 if (avc_has_perm(peer_sid, skb->secmark, 5918 SECCLASS_PACKET, secmark_perm, &ad)) 5919 return NF_DROP_ERR(-ECONNREFUSED); 5920 5921 if (peerlbl_active) { 5922 u32 if_sid; 5923 u32 node_sid; 5924 5925 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5926 return NF_DROP; 5927 if (avc_has_perm(peer_sid, if_sid, 5928 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5929 return NF_DROP_ERR(-ECONNREFUSED); 5930 5931 if (sel_netnode_sid(addrp, family, &node_sid)) 5932 return NF_DROP; 5933 if (avc_has_perm(peer_sid, node_sid, 5934 SECCLASS_NODE, NODE__SENDTO, &ad)) 5935 return NF_DROP_ERR(-ECONNREFUSED); 5936 } 5937 5938 return NF_ACCEPT; 5939 } 5940 #endif /* CONFIG_NETFILTER */ 5941 5942 static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type) 5943 { 5944 struct sk_security_struct *sksec = sk->sk_security; 5945 struct common_audit_data ad; 5946 u8 driver; 5947 u8 xperm; 5948 5949 if (sock_skip_has_perm(sksec->sid)) 5950 return 0; 5951 5952 ad.type = LSM_AUDIT_DATA_NLMSGTYPE; 5953 ad.u.nlmsg_type = nlmsg_type; 5954 5955 driver = nlmsg_type >> 8; 5956 xperm = nlmsg_type & 0xff; 5957 5958 return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass, 5959 perms, driver, AVC_EXT_NLMSG, xperm, &ad); 5960 } 5961 5962 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5963 { 5964 int rc = 0; 5965 unsigned int msg_len; 5966 unsigned int data_len = skb->len; 5967 unsigned char *data = skb->data; 5968 struct nlmsghdr *nlh; 5969 struct sk_security_struct *sksec = selinux_sock(sk); 5970 u16 sclass = sksec->sclass; 5971 u32 perm; 5972 5973 while (data_len >= nlmsg_total_size(0)) { 5974 nlh = (struct nlmsghdr *)data; 5975 5976 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5977 * users which means we can't reject skb's with bogus 5978 * length fields; our solution is to follow what 5979 * netlink_rcv_skb() does and simply skip processing at 5980 * messages with length fields that are clearly junk 5981 */ 5982 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5983 return 0; 5984 5985 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5986 if (rc == 0) { 5987 if (selinux_policycap_netlink_xperm()) { 5988 rc = nlmsg_sock_has_extended_perms( 5989 sk, perm, nlh->nlmsg_type); 5990 } else { 5991 rc = sock_has_perm(sk, perm); 5992 } 5993 if (rc) 5994 return rc; 5995 } else if (rc == -EINVAL) { 5996 /* -EINVAL is a missing msg/perm mapping */ 5997 pr_warn_ratelimited("SELinux: unrecognized netlink" 5998 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5999 " pid=%d comm=%s\n", 6000 sk->sk_protocol, nlh->nlmsg_type, 6001 secclass_map[sclass - 1].name, 6002 task_pid_nr(current), current->comm); 6003 if (enforcing_enabled() && 6004 !security_get_allow_unknown()) 6005 return rc; 6006 rc = 0; 6007 } else if (rc == -ENOENT) { 6008 /* -ENOENT is a missing socket/class mapping, ignore */ 6009 rc = 0; 6010 } else { 6011 return rc; 6012 } 6013 6014 /* move to the next message after applying netlink padding */ 6015 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 6016 if (msg_len >= data_len) 6017 return 0; 6018 data_len -= msg_len; 6019 data += msg_len; 6020 } 6021 6022 return rc; 6023 } 6024 6025 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 6026 { 6027 isec->sclass = sclass; 6028 isec->sid = current_sid(); 6029 } 6030 6031 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 6032 u32 perms) 6033 { 6034 struct ipc_security_struct *isec; 6035 struct common_audit_data ad; 6036 u32 sid = current_sid(); 6037 6038 isec = selinux_ipc(ipc_perms); 6039 6040 ad.type = LSM_AUDIT_DATA_IPC; 6041 ad.u.ipc_id = ipc_perms->key; 6042 6043 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 6044 } 6045 6046 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 6047 { 6048 struct msg_security_struct *msec; 6049 6050 msec = selinux_msg_msg(msg); 6051 msec->sid = SECINITSID_UNLABELED; 6052 6053 return 0; 6054 } 6055 6056 /* message queue security operations */ 6057 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 6058 { 6059 struct ipc_security_struct *isec; 6060 struct common_audit_data ad; 6061 u32 sid = current_sid(); 6062 6063 isec = selinux_ipc(msq); 6064 ipc_init_security(isec, SECCLASS_MSGQ); 6065 6066 ad.type = LSM_AUDIT_DATA_IPC; 6067 ad.u.ipc_id = msq->key; 6068 6069 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6070 MSGQ__CREATE, &ad); 6071 } 6072 6073 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 6074 { 6075 struct ipc_security_struct *isec; 6076 struct common_audit_data ad; 6077 u32 sid = current_sid(); 6078 6079 isec = selinux_ipc(msq); 6080 6081 ad.type = LSM_AUDIT_DATA_IPC; 6082 ad.u.ipc_id = msq->key; 6083 6084 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6085 MSGQ__ASSOCIATE, &ad); 6086 } 6087 6088 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 6089 { 6090 u32 perms; 6091 6092 switch (cmd) { 6093 case IPC_INFO: 6094 case MSG_INFO: 6095 /* No specific object, just general system-wide information. */ 6096 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6097 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6098 case IPC_STAT: 6099 case MSG_STAT: 6100 case MSG_STAT_ANY: 6101 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6102 break; 6103 case IPC_SET: 6104 perms = MSGQ__SETATTR; 6105 break; 6106 case IPC_RMID: 6107 perms = MSGQ__DESTROY; 6108 break; 6109 default: 6110 return 0; 6111 } 6112 6113 return ipc_has_perm(msq, perms); 6114 } 6115 6116 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6117 { 6118 struct ipc_security_struct *isec; 6119 struct msg_security_struct *msec; 6120 struct common_audit_data ad; 6121 u32 sid = current_sid(); 6122 int rc; 6123 6124 isec = selinux_ipc(msq); 6125 msec = selinux_msg_msg(msg); 6126 6127 /* 6128 * First time through, need to assign label to the message 6129 */ 6130 if (msec->sid == SECINITSID_UNLABELED) { 6131 /* 6132 * Compute new sid based on current process and 6133 * message queue this message will be stored in 6134 */ 6135 rc = security_transition_sid(sid, isec->sid, 6136 SECCLASS_MSG, NULL, &msec->sid); 6137 if (rc) 6138 return rc; 6139 } 6140 6141 ad.type = LSM_AUDIT_DATA_IPC; 6142 ad.u.ipc_id = msq->key; 6143 6144 /* Can this process write to the queue? */ 6145 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6146 MSGQ__WRITE, &ad); 6147 if (!rc) 6148 /* Can this process send the message */ 6149 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6150 MSG__SEND, &ad); 6151 if (!rc) 6152 /* Can the message be put in the queue? */ 6153 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6154 MSGQ__ENQUEUE, &ad); 6155 6156 return rc; 6157 } 6158 6159 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6160 struct task_struct *target, 6161 long type, int mode) 6162 { 6163 struct ipc_security_struct *isec; 6164 struct msg_security_struct *msec; 6165 struct common_audit_data ad; 6166 u32 sid = task_sid_obj(target); 6167 int rc; 6168 6169 isec = selinux_ipc(msq); 6170 msec = selinux_msg_msg(msg); 6171 6172 ad.type = LSM_AUDIT_DATA_IPC; 6173 ad.u.ipc_id = msq->key; 6174 6175 rc = avc_has_perm(sid, isec->sid, 6176 SECCLASS_MSGQ, MSGQ__READ, &ad); 6177 if (!rc) 6178 rc = avc_has_perm(sid, msec->sid, 6179 SECCLASS_MSG, MSG__RECEIVE, &ad); 6180 return rc; 6181 } 6182 6183 /* Shared Memory security operations */ 6184 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6185 { 6186 struct ipc_security_struct *isec; 6187 struct common_audit_data ad; 6188 u32 sid = current_sid(); 6189 6190 isec = selinux_ipc(shp); 6191 ipc_init_security(isec, SECCLASS_SHM); 6192 6193 ad.type = LSM_AUDIT_DATA_IPC; 6194 ad.u.ipc_id = shp->key; 6195 6196 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6197 SHM__CREATE, &ad); 6198 } 6199 6200 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6201 { 6202 struct ipc_security_struct *isec; 6203 struct common_audit_data ad; 6204 u32 sid = current_sid(); 6205 6206 isec = selinux_ipc(shp); 6207 6208 ad.type = LSM_AUDIT_DATA_IPC; 6209 ad.u.ipc_id = shp->key; 6210 6211 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6212 SHM__ASSOCIATE, &ad); 6213 } 6214 6215 /* Note, at this point, shp is locked down */ 6216 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6217 { 6218 u32 perms; 6219 6220 switch (cmd) { 6221 case IPC_INFO: 6222 case SHM_INFO: 6223 /* No specific object, just general system-wide information. */ 6224 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6225 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6226 case IPC_STAT: 6227 case SHM_STAT: 6228 case SHM_STAT_ANY: 6229 perms = SHM__GETATTR | SHM__ASSOCIATE; 6230 break; 6231 case IPC_SET: 6232 perms = SHM__SETATTR; 6233 break; 6234 case SHM_LOCK: 6235 case SHM_UNLOCK: 6236 perms = SHM__LOCK; 6237 break; 6238 case IPC_RMID: 6239 perms = SHM__DESTROY; 6240 break; 6241 default: 6242 return 0; 6243 } 6244 6245 return ipc_has_perm(shp, perms); 6246 } 6247 6248 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6249 char __user *shmaddr, int shmflg) 6250 { 6251 u32 perms; 6252 6253 if (shmflg & SHM_RDONLY) 6254 perms = SHM__READ; 6255 else 6256 perms = SHM__READ | SHM__WRITE; 6257 6258 return ipc_has_perm(shp, perms); 6259 } 6260 6261 /* Semaphore security operations */ 6262 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6263 { 6264 struct ipc_security_struct *isec; 6265 struct common_audit_data ad; 6266 u32 sid = current_sid(); 6267 6268 isec = selinux_ipc(sma); 6269 ipc_init_security(isec, SECCLASS_SEM); 6270 6271 ad.type = LSM_AUDIT_DATA_IPC; 6272 ad.u.ipc_id = sma->key; 6273 6274 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6275 SEM__CREATE, &ad); 6276 } 6277 6278 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6279 { 6280 struct ipc_security_struct *isec; 6281 struct common_audit_data ad; 6282 u32 sid = current_sid(); 6283 6284 isec = selinux_ipc(sma); 6285 6286 ad.type = LSM_AUDIT_DATA_IPC; 6287 ad.u.ipc_id = sma->key; 6288 6289 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6290 SEM__ASSOCIATE, &ad); 6291 } 6292 6293 /* Note, at this point, sma is locked down */ 6294 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6295 { 6296 int err; 6297 u32 perms; 6298 6299 switch (cmd) { 6300 case IPC_INFO: 6301 case SEM_INFO: 6302 /* No specific object, just general system-wide information. */ 6303 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6304 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6305 case GETPID: 6306 case GETNCNT: 6307 case GETZCNT: 6308 perms = SEM__GETATTR; 6309 break; 6310 case GETVAL: 6311 case GETALL: 6312 perms = SEM__READ; 6313 break; 6314 case SETVAL: 6315 case SETALL: 6316 perms = SEM__WRITE; 6317 break; 6318 case IPC_RMID: 6319 perms = SEM__DESTROY; 6320 break; 6321 case IPC_SET: 6322 perms = SEM__SETATTR; 6323 break; 6324 case IPC_STAT: 6325 case SEM_STAT: 6326 case SEM_STAT_ANY: 6327 perms = SEM__GETATTR | SEM__ASSOCIATE; 6328 break; 6329 default: 6330 return 0; 6331 } 6332 6333 err = ipc_has_perm(sma, perms); 6334 return err; 6335 } 6336 6337 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6338 struct sembuf *sops, unsigned nsops, int alter) 6339 { 6340 u32 perms; 6341 6342 if (alter) 6343 perms = SEM__READ | SEM__WRITE; 6344 else 6345 perms = SEM__READ; 6346 6347 return ipc_has_perm(sma, perms); 6348 } 6349 6350 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6351 { 6352 u32 av = 0; 6353 6354 av = 0; 6355 if (flag & S_IRUGO) 6356 av |= IPC__UNIX_READ; 6357 if (flag & S_IWUGO) 6358 av |= IPC__UNIX_WRITE; 6359 6360 if (av == 0) 6361 return 0; 6362 6363 return ipc_has_perm(ipcp, av); 6364 } 6365 6366 static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp, 6367 struct lsm_prop *prop) 6368 { 6369 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6370 prop->selinux.secid = isec->sid; 6371 } 6372 6373 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6374 { 6375 if (inode) 6376 inode_doinit_with_dentry(inode, dentry); 6377 } 6378 6379 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p, 6380 char **value) 6381 { 6382 const struct task_security_struct *tsec; 6383 int error; 6384 u32 sid; 6385 u32 len; 6386 6387 rcu_read_lock(); 6388 tsec = selinux_cred(__task_cred(p)); 6389 if (p != current) { 6390 error = avc_has_perm(current_sid(), tsec->sid, 6391 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6392 if (error) 6393 goto err_unlock; 6394 } 6395 switch (attr) { 6396 case LSM_ATTR_CURRENT: 6397 sid = tsec->sid; 6398 break; 6399 case LSM_ATTR_PREV: 6400 sid = tsec->osid; 6401 break; 6402 case LSM_ATTR_EXEC: 6403 sid = tsec->exec_sid; 6404 break; 6405 case LSM_ATTR_FSCREATE: 6406 sid = tsec->create_sid; 6407 break; 6408 case LSM_ATTR_KEYCREATE: 6409 sid = tsec->keycreate_sid; 6410 break; 6411 case LSM_ATTR_SOCKCREATE: 6412 sid = tsec->sockcreate_sid; 6413 break; 6414 default: 6415 error = -EOPNOTSUPP; 6416 goto err_unlock; 6417 } 6418 rcu_read_unlock(); 6419 6420 if (sid == SECSID_NULL) { 6421 *value = NULL; 6422 return 0; 6423 } 6424 6425 error = security_sid_to_context(sid, value, &len); 6426 if (error) 6427 return error; 6428 return len; 6429 6430 err_unlock: 6431 rcu_read_unlock(); 6432 return error; 6433 } 6434 6435 static int selinux_lsm_setattr(u64 attr, void *value, size_t size) 6436 { 6437 struct task_security_struct *tsec; 6438 struct cred *new; 6439 u32 mysid = current_sid(), sid = 0, ptsid; 6440 int error; 6441 char *str = value; 6442 6443 /* 6444 * Basic control over ability to set these attributes at all. 6445 */ 6446 switch (attr) { 6447 case LSM_ATTR_EXEC: 6448 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6449 PROCESS__SETEXEC, NULL); 6450 break; 6451 case LSM_ATTR_FSCREATE: 6452 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6453 PROCESS__SETFSCREATE, NULL); 6454 break; 6455 case LSM_ATTR_KEYCREATE: 6456 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6457 PROCESS__SETKEYCREATE, NULL); 6458 break; 6459 case LSM_ATTR_SOCKCREATE: 6460 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6461 PROCESS__SETSOCKCREATE, NULL); 6462 break; 6463 case LSM_ATTR_CURRENT: 6464 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6465 PROCESS__SETCURRENT, NULL); 6466 break; 6467 default: 6468 error = -EOPNOTSUPP; 6469 break; 6470 } 6471 if (error) 6472 return error; 6473 6474 /* Obtain a SID for the context, if one was specified. */ 6475 if (size && str[0] && str[0] != '\n') { 6476 if (str[size-1] == '\n') { 6477 str[size-1] = 0; 6478 size--; 6479 } 6480 error = security_context_to_sid(value, size, 6481 &sid, GFP_KERNEL); 6482 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) { 6483 if (!has_cap_mac_admin(true)) { 6484 struct audit_buffer *ab; 6485 size_t audit_size; 6486 6487 /* We strip a nul only if it is at the end, 6488 * otherwise the context contains a nul and 6489 * we should audit that */ 6490 if (str[size - 1] == '\0') 6491 audit_size = size - 1; 6492 else 6493 audit_size = size; 6494 ab = audit_log_start(audit_context(), 6495 GFP_ATOMIC, 6496 AUDIT_SELINUX_ERR); 6497 if (!ab) 6498 return error; 6499 audit_log_format(ab, "op=fscreate invalid_context="); 6500 audit_log_n_untrustedstring(ab, value, 6501 audit_size); 6502 audit_log_end(ab); 6503 6504 return error; 6505 } 6506 error = security_context_to_sid_force(value, size, 6507 &sid); 6508 } 6509 if (error) 6510 return error; 6511 } 6512 6513 new = prepare_creds(); 6514 if (!new) 6515 return -ENOMEM; 6516 6517 /* Permission checking based on the specified context is 6518 performed during the actual operation (execve, 6519 open/mkdir/...), when we know the full context of the 6520 operation. See selinux_bprm_creds_for_exec for the execve 6521 checks and may_create for the file creation checks. The 6522 operation will then fail if the context is not permitted. */ 6523 tsec = selinux_cred(new); 6524 if (attr == LSM_ATTR_EXEC) { 6525 tsec->exec_sid = sid; 6526 } else if (attr == LSM_ATTR_FSCREATE) { 6527 tsec->create_sid = sid; 6528 } else if (attr == LSM_ATTR_KEYCREATE) { 6529 if (sid) { 6530 error = avc_has_perm(mysid, sid, 6531 SECCLASS_KEY, KEY__CREATE, NULL); 6532 if (error) 6533 goto abort_change; 6534 } 6535 tsec->keycreate_sid = sid; 6536 } else if (attr == LSM_ATTR_SOCKCREATE) { 6537 tsec->sockcreate_sid = sid; 6538 } else if (attr == LSM_ATTR_CURRENT) { 6539 error = -EINVAL; 6540 if (sid == 0) 6541 goto abort_change; 6542 6543 if (!current_is_single_threaded()) { 6544 error = security_bounded_transition(tsec->sid, sid); 6545 if (error) 6546 goto abort_change; 6547 } 6548 6549 /* Check permissions for the transition. */ 6550 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6551 PROCESS__DYNTRANSITION, NULL); 6552 if (error) 6553 goto abort_change; 6554 6555 /* Check for ptracing, and update the task SID if ok. 6556 Otherwise, leave SID unchanged and fail. */ 6557 ptsid = ptrace_parent_sid(); 6558 if (ptsid != 0) { 6559 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6560 PROCESS__PTRACE, NULL); 6561 if (error) 6562 goto abort_change; 6563 } 6564 6565 tsec->sid = sid; 6566 } else { 6567 error = -EINVAL; 6568 goto abort_change; 6569 } 6570 6571 commit_creds(new); 6572 return size; 6573 6574 abort_change: 6575 abort_creds(new); 6576 return error; 6577 } 6578 6579 /** 6580 * selinux_getselfattr - Get SELinux current task attributes 6581 * @attr: the requested attribute 6582 * @ctx: buffer to receive the result 6583 * @size: buffer size (input), buffer size used (output) 6584 * @flags: unused 6585 * 6586 * Fill the passed user space @ctx with the details of the requested 6587 * attribute. 6588 * 6589 * Returns the number of attributes on success, an error code otherwise. 6590 * There will only ever be one attribute. 6591 */ 6592 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, 6593 u32 *size, u32 flags) 6594 { 6595 int rc; 6596 char *val = NULL; 6597 int val_len; 6598 6599 val_len = selinux_lsm_getattr(attr, current, &val); 6600 if (val_len < 0) 6601 return val_len; 6602 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0); 6603 kfree(val); 6604 return (!rc ? 1 : rc); 6605 } 6606 6607 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx, 6608 u32 size, u32 flags) 6609 { 6610 int rc; 6611 6612 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len); 6613 if (rc > 0) 6614 return 0; 6615 return rc; 6616 } 6617 6618 static int selinux_getprocattr(struct task_struct *p, 6619 const char *name, char **value) 6620 { 6621 unsigned int attr = lsm_name_to_attr(name); 6622 int rc; 6623 6624 if (attr) { 6625 rc = selinux_lsm_getattr(attr, p, value); 6626 if (rc != -EOPNOTSUPP) 6627 return rc; 6628 } 6629 6630 return -EINVAL; 6631 } 6632 6633 static int selinux_setprocattr(const char *name, void *value, size_t size) 6634 { 6635 int attr = lsm_name_to_attr(name); 6636 6637 if (attr) 6638 return selinux_lsm_setattr(attr, value, size); 6639 return -EINVAL; 6640 } 6641 6642 static int selinux_ismaclabel(const char *name) 6643 { 6644 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6645 } 6646 6647 static int selinux_secid_to_secctx(u32 secid, struct lsm_context *cp) 6648 { 6649 u32 seclen; 6650 int ret; 6651 6652 if (cp) { 6653 cp->id = LSM_ID_SELINUX; 6654 ret = security_sid_to_context(secid, &cp->context, &cp->len); 6655 if (ret < 0) 6656 return ret; 6657 return cp->len; 6658 } 6659 ret = security_sid_to_context(secid, NULL, &seclen); 6660 if (ret < 0) 6661 return ret; 6662 return seclen; 6663 } 6664 6665 static int selinux_lsmprop_to_secctx(struct lsm_prop *prop, 6666 struct lsm_context *cp) 6667 { 6668 return selinux_secid_to_secctx(prop->selinux.secid, cp); 6669 } 6670 6671 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6672 { 6673 return security_context_to_sid(secdata, seclen, 6674 secid, GFP_KERNEL); 6675 } 6676 6677 static void selinux_release_secctx(struct lsm_context *cp) 6678 { 6679 if (cp->id == LSM_ID_SELINUX) { 6680 kfree(cp->context); 6681 cp->context = NULL; 6682 cp->id = LSM_ID_UNDEF; 6683 } 6684 } 6685 6686 static void selinux_inode_invalidate_secctx(struct inode *inode) 6687 { 6688 struct inode_security_struct *isec = selinux_inode(inode); 6689 6690 spin_lock(&isec->lock); 6691 isec->initialized = LABEL_INVALID; 6692 spin_unlock(&isec->lock); 6693 } 6694 6695 /* 6696 * called with inode->i_mutex locked 6697 */ 6698 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6699 { 6700 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6701 ctx, ctxlen, 0); 6702 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6703 return rc == -EOPNOTSUPP ? 0 : rc; 6704 } 6705 6706 /* 6707 * called with inode->i_mutex locked 6708 */ 6709 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6710 { 6711 return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6712 ctx, ctxlen, 0, NULL); 6713 } 6714 6715 static int selinux_inode_getsecctx(struct inode *inode, struct lsm_context *cp) 6716 { 6717 int len; 6718 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6719 XATTR_SELINUX_SUFFIX, 6720 (void **)&cp->context, true); 6721 if (len < 0) 6722 return len; 6723 cp->len = len; 6724 cp->id = LSM_ID_SELINUX; 6725 return 0; 6726 } 6727 #ifdef CONFIG_KEYS 6728 6729 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6730 unsigned long flags) 6731 { 6732 const struct task_security_struct *tsec; 6733 struct key_security_struct *ksec = selinux_key(k); 6734 6735 tsec = selinux_cred(cred); 6736 if (tsec->keycreate_sid) 6737 ksec->sid = tsec->keycreate_sid; 6738 else 6739 ksec->sid = tsec->sid; 6740 6741 return 0; 6742 } 6743 6744 static int selinux_key_permission(key_ref_t key_ref, 6745 const struct cred *cred, 6746 enum key_need_perm need_perm) 6747 { 6748 struct key *key; 6749 struct key_security_struct *ksec; 6750 u32 perm, sid; 6751 6752 switch (need_perm) { 6753 case KEY_NEED_VIEW: 6754 perm = KEY__VIEW; 6755 break; 6756 case KEY_NEED_READ: 6757 perm = KEY__READ; 6758 break; 6759 case KEY_NEED_WRITE: 6760 perm = KEY__WRITE; 6761 break; 6762 case KEY_NEED_SEARCH: 6763 perm = KEY__SEARCH; 6764 break; 6765 case KEY_NEED_LINK: 6766 perm = KEY__LINK; 6767 break; 6768 case KEY_NEED_SETATTR: 6769 perm = KEY__SETATTR; 6770 break; 6771 case KEY_NEED_UNLINK: 6772 case KEY_SYSADMIN_OVERRIDE: 6773 case KEY_AUTHTOKEN_OVERRIDE: 6774 case KEY_DEFER_PERM_CHECK: 6775 return 0; 6776 default: 6777 WARN_ON(1); 6778 return -EPERM; 6779 6780 } 6781 6782 sid = cred_sid(cred); 6783 key = key_ref_to_ptr(key_ref); 6784 ksec = selinux_key(key); 6785 6786 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6787 } 6788 6789 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6790 { 6791 struct key_security_struct *ksec = selinux_key(key); 6792 char *context = NULL; 6793 unsigned len; 6794 int rc; 6795 6796 rc = security_sid_to_context(ksec->sid, 6797 &context, &len); 6798 if (!rc) 6799 rc = len; 6800 *_buffer = context; 6801 return rc; 6802 } 6803 6804 #ifdef CONFIG_KEY_NOTIFICATIONS 6805 static int selinux_watch_key(struct key *key) 6806 { 6807 struct key_security_struct *ksec = selinux_key(key); 6808 u32 sid = current_sid(); 6809 6810 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6811 } 6812 #endif 6813 #endif 6814 6815 #ifdef CONFIG_SECURITY_INFINIBAND 6816 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6817 { 6818 struct common_audit_data ad; 6819 int err; 6820 u32 sid = 0; 6821 struct ib_security_struct *sec = ib_sec; 6822 struct lsm_ibpkey_audit ibpkey; 6823 6824 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6825 if (err) 6826 return err; 6827 6828 ad.type = LSM_AUDIT_DATA_IBPKEY; 6829 ibpkey.subnet_prefix = subnet_prefix; 6830 ibpkey.pkey = pkey_val; 6831 ad.u.ibpkey = &ibpkey; 6832 return avc_has_perm(sec->sid, sid, 6833 SECCLASS_INFINIBAND_PKEY, 6834 INFINIBAND_PKEY__ACCESS, &ad); 6835 } 6836 6837 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6838 u8 port_num) 6839 { 6840 struct common_audit_data ad; 6841 int err; 6842 u32 sid = 0; 6843 struct ib_security_struct *sec = ib_sec; 6844 struct lsm_ibendport_audit ibendport; 6845 6846 err = security_ib_endport_sid(dev_name, port_num, 6847 &sid); 6848 6849 if (err) 6850 return err; 6851 6852 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6853 ibendport.dev_name = dev_name; 6854 ibendport.port = port_num; 6855 ad.u.ibendport = &ibendport; 6856 return avc_has_perm(sec->sid, sid, 6857 SECCLASS_INFINIBAND_ENDPORT, 6858 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6859 } 6860 6861 static int selinux_ib_alloc_security(void *ib_sec) 6862 { 6863 struct ib_security_struct *sec = selinux_ib(ib_sec); 6864 6865 sec->sid = current_sid(); 6866 return 0; 6867 } 6868 #endif 6869 6870 #ifdef CONFIG_BPF_SYSCALL 6871 static int selinux_bpf(int cmd, union bpf_attr *attr, 6872 unsigned int size) 6873 { 6874 u32 sid = current_sid(); 6875 int ret; 6876 6877 switch (cmd) { 6878 case BPF_MAP_CREATE: 6879 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6880 NULL); 6881 break; 6882 case BPF_PROG_LOAD: 6883 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6884 NULL); 6885 break; 6886 default: 6887 ret = 0; 6888 break; 6889 } 6890 6891 return ret; 6892 } 6893 6894 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6895 { 6896 u32 av = 0; 6897 6898 if (fmode & FMODE_READ) 6899 av |= BPF__MAP_READ; 6900 if (fmode & FMODE_WRITE) 6901 av |= BPF__MAP_WRITE; 6902 return av; 6903 } 6904 6905 /* This function will check the file pass through unix socket or binder to see 6906 * if it is a bpf related object. And apply corresponding checks on the bpf 6907 * object based on the type. The bpf maps and programs, not like other files and 6908 * socket, are using a shared anonymous inode inside the kernel as their inode. 6909 * So checking that inode cannot identify if the process have privilege to 6910 * access the bpf object and that's why we have to add this additional check in 6911 * selinux_file_receive and selinux_binder_transfer_files. 6912 */ 6913 static int bpf_fd_pass(const struct file *file, u32 sid) 6914 { 6915 struct bpf_security_struct *bpfsec; 6916 struct bpf_prog *prog; 6917 struct bpf_map *map; 6918 int ret; 6919 6920 if (file->f_op == &bpf_map_fops) { 6921 map = file->private_data; 6922 bpfsec = map->security; 6923 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6924 bpf_map_fmode_to_av(file->f_mode), NULL); 6925 if (ret) 6926 return ret; 6927 } else if (file->f_op == &bpf_prog_fops) { 6928 prog = file->private_data; 6929 bpfsec = prog->aux->security; 6930 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6931 BPF__PROG_RUN, NULL); 6932 if (ret) 6933 return ret; 6934 } 6935 return 0; 6936 } 6937 6938 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6939 { 6940 u32 sid = current_sid(); 6941 struct bpf_security_struct *bpfsec; 6942 6943 bpfsec = map->security; 6944 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6945 bpf_map_fmode_to_av(fmode), NULL); 6946 } 6947 6948 static int selinux_bpf_prog(struct bpf_prog *prog) 6949 { 6950 u32 sid = current_sid(); 6951 struct bpf_security_struct *bpfsec; 6952 6953 bpfsec = prog->aux->security; 6954 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6955 BPF__PROG_RUN, NULL); 6956 } 6957 6958 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 6959 struct bpf_token *token) 6960 { 6961 struct bpf_security_struct *bpfsec; 6962 6963 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6964 if (!bpfsec) 6965 return -ENOMEM; 6966 6967 bpfsec->sid = current_sid(); 6968 map->security = bpfsec; 6969 6970 return 0; 6971 } 6972 6973 static void selinux_bpf_map_free(struct bpf_map *map) 6974 { 6975 struct bpf_security_struct *bpfsec = map->security; 6976 6977 map->security = NULL; 6978 kfree(bpfsec); 6979 } 6980 6981 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 6982 struct bpf_token *token) 6983 { 6984 struct bpf_security_struct *bpfsec; 6985 6986 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6987 if (!bpfsec) 6988 return -ENOMEM; 6989 6990 bpfsec->sid = current_sid(); 6991 prog->aux->security = bpfsec; 6992 6993 return 0; 6994 } 6995 6996 static void selinux_bpf_prog_free(struct bpf_prog *prog) 6997 { 6998 struct bpf_security_struct *bpfsec = prog->aux->security; 6999 7000 prog->aux->security = NULL; 7001 kfree(bpfsec); 7002 } 7003 7004 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 7005 const struct path *path) 7006 { 7007 struct bpf_security_struct *bpfsec; 7008 7009 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 7010 if (!bpfsec) 7011 return -ENOMEM; 7012 7013 bpfsec->sid = current_sid(); 7014 token->security = bpfsec; 7015 7016 return 0; 7017 } 7018 7019 static void selinux_bpf_token_free(struct bpf_token *token) 7020 { 7021 struct bpf_security_struct *bpfsec = token->security; 7022 7023 token->security = NULL; 7024 kfree(bpfsec); 7025 } 7026 #endif 7027 7028 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 7029 .lbs_cred = sizeof(struct task_security_struct), 7030 .lbs_file = sizeof(struct file_security_struct), 7031 .lbs_inode = sizeof(struct inode_security_struct), 7032 .lbs_ipc = sizeof(struct ipc_security_struct), 7033 .lbs_key = sizeof(struct key_security_struct), 7034 .lbs_msg_msg = sizeof(struct msg_security_struct), 7035 #ifdef CONFIG_PERF_EVENTS 7036 .lbs_perf_event = sizeof(struct perf_event_security_struct), 7037 #endif 7038 .lbs_sock = sizeof(struct sk_security_struct), 7039 .lbs_superblock = sizeof(struct superblock_security_struct), 7040 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 7041 .lbs_tun_dev = sizeof(struct tun_security_struct), 7042 .lbs_ib = sizeof(struct ib_security_struct), 7043 }; 7044 7045 #ifdef CONFIG_PERF_EVENTS 7046 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 7047 { 7048 u32 requested, sid = current_sid(); 7049 7050 if (type == PERF_SECURITY_OPEN) 7051 requested = PERF_EVENT__OPEN; 7052 else if (type == PERF_SECURITY_CPU) 7053 requested = PERF_EVENT__CPU; 7054 else if (type == PERF_SECURITY_KERNEL) 7055 requested = PERF_EVENT__KERNEL; 7056 else if (type == PERF_SECURITY_TRACEPOINT) 7057 requested = PERF_EVENT__TRACEPOINT; 7058 else 7059 return -EINVAL; 7060 7061 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 7062 requested, NULL); 7063 } 7064 7065 static int selinux_perf_event_alloc(struct perf_event *event) 7066 { 7067 struct perf_event_security_struct *perfsec; 7068 7069 perfsec = selinux_perf_event(event->security); 7070 perfsec->sid = current_sid(); 7071 7072 return 0; 7073 } 7074 7075 static int selinux_perf_event_read(struct perf_event *event) 7076 { 7077 struct perf_event_security_struct *perfsec = event->security; 7078 u32 sid = current_sid(); 7079 7080 return avc_has_perm(sid, perfsec->sid, 7081 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 7082 } 7083 7084 static int selinux_perf_event_write(struct perf_event *event) 7085 { 7086 struct perf_event_security_struct *perfsec = event->security; 7087 u32 sid = current_sid(); 7088 7089 return avc_has_perm(sid, perfsec->sid, 7090 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 7091 } 7092 #endif 7093 7094 #ifdef CONFIG_IO_URING 7095 /** 7096 * selinux_uring_override_creds - check the requested cred override 7097 * @new: the target creds 7098 * 7099 * Check to see if the current task is allowed to override it's credentials 7100 * to service an io_uring operation. 7101 */ 7102 static int selinux_uring_override_creds(const struct cred *new) 7103 { 7104 return avc_has_perm(current_sid(), cred_sid(new), 7105 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 7106 } 7107 7108 /** 7109 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 7110 * 7111 * Check to see if the current task is allowed to create a new io_uring 7112 * kernel polling thread. 7113 */ 7114 static int selinux_uring_sqpoll(void) 7115 { 7116 u32 sid = current_sid(); 7117 7118 return avc_has_perm(sid, sid, 7119 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 7120 } 7121 7122 /** 7123 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 7124 * @ioucmd: the io_uring command structure 7125 * 7126 * Check to see if the current domain is allowed to execute an 7127 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 7128 * 7129 */ 7130 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 7131 { 7132 struct file *file = ioucmd->file; 7133 struct inode *inode = file_inode(file); 7134 struct inode_security_struct *isec = selinux_inode(inode); 7135 struct common_audit_data ad; 7136 7137 ad.type = LSM_AUDIT_DATA_FILE; 7138 ad.u.file = file; 7139 7140 return avc_has_perm(current_sid(), isec->sid, 7141 SECCLASS_IO_URING, IO_URING__CMD, &ad); 7142 } 7143 #endif /* CONFIG_IO_URING */ 7144 7145 static const struct lsm_id selinux_lsmid = { 7146 .name = "selinux", 7147 .id = LSM_ID_SELINUX, 7148 }; 7149 7150 /* 7151 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 7152 * 1. any hooks that don't belong to (2.) or (3.) below, 7153 * 2. hooks that both access structures allocated by other hooks, and allocate 7154 * structures that can be later accessed by other hooks (mostly "cloning" 7155 * hooks), 7156 * 3. hooks that only allocate structures that can be later accessed by other 7157 * hooks ("allocating" hooks). 7158 * 7159 * Please follow block comment delimiters in the list to keep this order. 7160 */ 7161 static struct security_hook_list selinux_hooks[] __ro_after_init = { 7162 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 7163 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 7164 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 7165 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 7166 7167 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 7168 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 7169 LSM_HOOK_INIT(capget, selinux_capget), 7170 LSM_HOOK_INIT(capset, selinux_capset), 7171 LSM_HOOK_INIT(capable, selinux_capable), 7172 LSM_HOOK_INIT(quotactl, selinux_quotactl), 7173 LSM_HOOK_INIT(quota_on, selinux_quota_on), 7174 LSM_HOOK_INIT(syslog, selinux_syslog), 7175 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 7176 7177 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 7178 7179 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 7180 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 7181 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 7182 7183 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 7184 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 7185 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 7186 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 7187 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 7188 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 7189 LSM_HOOK_INIT(sb_mount, selinux_mount), 7190 LSM_HOOK_INIT(sb_umount, selinux_umount), 7191 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7192 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7193 7194 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7195 7196 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7197 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7198 7199 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7200 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7201 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7202 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7203 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7204 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7205 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7206 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7207 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7208 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7209 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7210 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7211 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7212 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7213 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7214 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7215 LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap), 7216 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7217 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7218 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7219 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7220 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7221 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7222 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7223 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7224 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7225 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7226 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7227 LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop), 7228 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7229 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7230 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7231 7232 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7233 7234 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7235 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7236 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7237 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat), 7238 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7239 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7240 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7241 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7242 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7243 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7244 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7245 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7246 7247 LSM_HOOK_INIT(file_open, selinux_file_open), 7248 7249 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7250 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7251 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7252 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7253 LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop), 7254 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7255 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7256 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7257 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7258 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7259 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7260 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7261 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7262 LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj), 7263 LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj), 7264 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7265 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7266 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7267 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7268 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7269 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7270 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7271 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7272 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7273 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7274 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7275 7276 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7277 LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop), 7278 7279 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7280 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7281 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7282 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7283 7284 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7285 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7286 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7287 7288 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7289 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7290 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7291 7292 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7293 7294 LSM_HOOK_INIT(getselfattr, selinux_getselfattr), 7295 LSM_HOOK_INIT(setselfattr, selinux_setselfattr), 7296 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7297 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7298 7299 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7300 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7301 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7302 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7303 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7304 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7305 7306 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7307 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7308 7309 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7310 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7311 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7312 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7313 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7314 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7315 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7316 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7317 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7318 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7319 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7320 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7321 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7322 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7323 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7324 LSM_HOOK_INIT(socket_getpeersec_stream, 7325 selinux_socket_getpeersec_stream), 7326 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7327 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7328 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7329 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7330 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7331 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7332 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7333 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7334 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7335 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7336 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7337 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7338 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7339 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7340 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7341 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7342 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7343 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7344 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7345 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7346 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7347 #ifdef CONFIG_SECURITY_INFINIBAND 7348 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7349 LSM_HOOK_INIT(ib_endport_manage_subnet, 7350 selinux_ib_endport_manage_subnet), 7351 #endif 7352 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7353 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7354 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7355 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7356 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7357 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7358 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7359 selinux_xfrm_state_pol_flow_match), 7360 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7361 #endif 7362 7363 #ifdef CONFIG_KEYS 7364 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7365 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7366 #ifdef CONFIG_KEY_NOTIFICATIONS 7367 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7368 #endif 7369 #endif 7370 7371 #ifdef CONFIG_AUDIT 7372 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7373 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7374 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7375 #endif 7376 7377 #ifdef CONFIG_BPF_SYSCALL 7378 LSM_HOOK_INIT(bpf, selinux_bpf), 7379 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7380 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7381 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free), 7382 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free), 7383 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free), 7384 #endif 7385 7386 #ifdef CONFIG_PERF_EVENTS 7387 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7388 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7389 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7390 #endif 7391 7392 #ifdef CONFIG_IO_URING 7393 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7394 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7395 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7396 #endif 7397 7398 /* 7399 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7400 */ 7401 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7402 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7403 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7404 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7405 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7406 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7407 #endif 7408 7409 /* 7410 * PUT "ALLOCATING" HOOKS HERE 7411 */ 7412 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7413 LSM_HOOK_INIT(msg_queue_alloc_security, 7414 selinux_msg_queue_alloc_security), 7415 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7416 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7417 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7418 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7419 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7420 LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx), 7421 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7422 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7423 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7424 #ifdef CONFIG_SECURITY_INFINIBAND 7425 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7426 #endif 7427 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7428 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7429 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7430 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7431 selinux_xfrm_state_alloc_acquire), 7432 #endif 7433 #ifdef CONFIG_KEYS 7434 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7435 #endif 7436 #ifdef CONFIG_AUDIT 7437 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7438 #endif 7439 #ifdef CONFIG_BPF_SYSCALL 7440 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create), 7441 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load), 7442 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create), 7443 #endif 7444 #ifdef CONFIG_PERF_EVENTS 7445 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7446 #endif 7447 }; 7448 7449 static __init int selinux_init(void) 7450 { 7451 pr_info("SELinux: Initializing.\n"); 7452 7453 memset(&selinux_state, 0, sizeof(selinux_state)); 7454 enforcing_set(selinux_enforcing_boot); 7455 selinux_avc_init(); 7456 mutex_init(&selinux_state.status_lock); 7457 mutex_init(&selinux_state.policy_mutex); 7458 7459 /* Set the security state for the initial task. */ 7460 cred_init_security(); 7461 7462 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7463 if (!default_noexec) 7464 pr_notice("SELinux: virtual memory is executable by default\n"); 7465 7466 avc_init(); 7467 7468 avtab_cache_init(); 7469 7470 ebitmap_cache_init(); 7471 7472 hashtab_cache_init(); 7473 7474 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), 7475 &selinux_lsmid); 7476 7477 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7478 panic("SELinux: Unable to register AVC netcache callback\n"); 7479 7480 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7481 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7482 7483 if (selinux_enforcing_boot) 7484 pr_debug("SELinux: Starting in enforcing mode\n"); 7485 else 7486 pr_debug("SELinux: Starting in permissive mode\n"); 7487 7488 fs_validate_description("selinux", selinux_fs_parameters); 7489 7490 return 0; 7491 } 7492 7493 static void delayed_superblock_init(struct super_block *sb, void *unused) 7494 { 7495 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7496 } 7497 7498 void selinux_complete_init(void) 7499 { 7500 pr_debug("SELinux: Completing initialization.\n"); 7501 7502 /* Set up any superblocks initialized prior to the policy load. */ 7503 pr_debug("SELinux: Setting up existing superblocks.\n"); 7504 iterate_supers(delayed_superblock_init, NULL); 7505 } 7506 7507 /* SELinux requires early initialization in order to label 7508 all processes and objects when they are created. */ 7509 DEFINE_LSM(selinux) = { 7510 .name = "selinux", 7511 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7512 .enabled = &selinux_enabled_boot, 7513 .blobs = &selinux_blob_sizes, 7514 .init = selinux_init, 7515 }; 7516 7517 #if defined(CONFIG_NETFILTER) 7518 static const struct nf_hook_ops selinux_nf_ops[] = { 7519 { 7520 .hook = selinux_ip_postroute, 7521 .pf = NFPROTO_IPV4, 7522 .hooknum = NF_INET_POST_ROUTING, 7523 .priority = NF_IP_PRI_SELINUX_LAST, 7524 }, 7525 { 7526 .hook = selinux_ip_forward, 7527 .pf = NFPROTO_IPV4, 7528 .hooknum = NF_INET_FORWARD, 7529 .priority = NF_IP_PRI_SELINUX_FIRST, 7530 }, 7531 { 7532 .hook = selinux_ip_output, 7533 .pf = NFPROTO_IPV4, 7534 .hooknum = NF_INET_LOCAL_OUT, 7535 .priority = NF_IP_PRI_SELINUX_FIRST, 7536 }, 7537 #if IS_ENABLED(CONFIG_IPV6) 7538 { 7539 .hook = selinux_ip_postroute, 7540 .pf = NFPROTO_IPV6, 7541 .hooknum = NF_INET_POST_ROUTING, 7542 .priority = NF_IP6_PRI_SELINUX_LAST, 7543 }, 7544 { 7545 .hook = selinux_ip_forward, 7546 .pf = NFPROTO_IPV6, 7547 .hooknum = NF_INET_FORWARD, 7548 .priority = NF_IP6_PRI_SELINUX_FIRST, 7549 }, 7550 { 7551 .hook = selinux_ip_output, 7552 .pf = NFPROTO_IPV6, 7553 .hooknum = NF_INET_LOCAL_OUT, 7554 .priority = NF_IP6_PRI_SELINUX_FIRST, 7555 }, 7556 #endif /* IPV6 */ 7557 }; 7558 7559 static int __net_init selinux_nf_register(struct net *net) 7560 { 7561 return nf_register_net_hooks(net, selinux_nf_ops, 7562 ARRAY_SIZE(selinux_nf_ops)); 7563 } 7564 7565 static void __net_exit selinux_nf_unregister(struct net *net) 7566 { 7567 nf_unregister_net_hooks(net, selinux_nf_ops, 7568 ARRAY_SIZE(selinux_nf_ops)); 7569 } 7570 7571 static struct pernet_operations selinux_net_ops = { 7572 .init = selinux_nf_register, 7573 .exit = selinux_nf_unregister, 7574 }; 7575 7576 static int __init selinux_nf_ip_init(void) 7577 { 7578 int err; 7579 7580 if (!selinux_enabled_boot) 7581 return 0; 7582 7583 pr_debug("SELinux: Registering netfilter hooks\n"); 7584 7585 err = register_pernet_subsys(&selinux_net_ops); 7586 if (err) 7587 panic("SELinux: register_pernet_subsys: error %d\n", err); 7588 7589 return 0; 7590 } 7591 __initcall(selinux_nf_ip_init); 7592 #endif /* CONFIG_NETFILTER */ 7593