1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Security-Enhanced Linux (SELinux) security module 4 * 5 * This file contains the SELinux hook function implementations. 6 * 7 * Authors: Stephen Smalley, <stephen.smalley.work@gmail.com> 8 * Chris Vance, <cvance@nai.com> 9 * Wayne Salamon, <wsalamon@nai.com> 10 * James Morris <jmorris@redhat.com> 11 * 12 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 13 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> 14 * Eric Paris <eparis@redhat.com> 15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 16 * <dgoeddel@trustedcs.com> 17 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. 18 * Paul Moore <paul@paul-moore.com> 19 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 20 * Yuichi Nakamura <ynakam@hitachisoft.jp> 21 * Copyright (C) 2016 Mellanox Technologies 22 */ 23 24 #include <linux/init.h> 25 #include <linux/kd.h> 26 #include <linux/kernel.h> 27 #include <linux/kernel_read_file.h> 28 #include <linux/errno.h> 29 #include <linux/sched/signal.h> 30 #include <linux/sched/task.h> 31 #include <linux/lsm_hooks.h> 32 #include <linux/xattr.h> 33 #include <linux/capability.h> 34 #include <linux/unistd.h> 35 #include <linux/mm.h> 36 #include <linux/mman.h> 37 #include <linux/slab.h> 38 #include <linux/pagemap.h> 39 #include <linux/proc_fs.h> 40 #include <linux/swap.h> 41 #include <linux/spinlock.h> 42 #include <linux/syscalls.h> 43 #include <linux/dcache.h> 44 #include <linux/file.h> 45 #include <linux/fdtable.h> 46 #include <linux/namei.h> 47 #include <linux/mount.h> 48 #include <linux/fs_context.h> 49 #include <linux/fs_parser.h> 50 #include <linux/netfilter_ipv4.h> 51 #include <linux/netfilter_ipv6.h> 52 #include <linux/tty.h> 53 #include <net/icmp.h> 54 #include <net/ip.h> /* for local_port_range[] */ 55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 56 #include <net/inet_connection_sock.h> 57 #include <net/net_namespace.h> 58 #include <net/netlabel.h> 59 #include <linux/uaccess.h> 60 #include <asm/ioctls.h> 61 #include <linux/atomic.h> 62 #include <linux/bitops.h> 63 #include <linux/interrupt.h> 64 #include <linux/netdevice.h> /* for network interface checks */ 65 #include <net/netlink.h> 66 #include <linux/tcp.h> 67 #include <linux/udp.h> 68 #include <linux/dccp.h> 69 #include <linux/sctp.h> 70 #include <net/sctp/structs.h> 71 #include <linux/quota.h> 72 #include <linux/un.h> /* for Unix socket types */ 73 #include <net/af_unix.h> /* for Unix socket types */ 74 #include <linux/parser.h> 75 #include <linux/nfs_mount.h> 76 #include <net/ipv6.h> 77 #include <linux/hugetlb.h> 78 #include <linux/personality.h> 79 #include <linux/audit.h> 80 #include <linux/string.h> 81 #include <linux/mutex.h> 82 #include <linux/posix-timers.h> 83 #include <linux/syslog.h> 84 #include <linux/user_namespace.h> 85 #include <linux/export.h> 86 #include <linux/msg.h> 87 #include <linux/shm.h> 88 #include <linux/bpf.h> 89 #include <linux/kernfs.h> 90 #include <linux/stringhash.h> /* for hashlen_string() */ 91 #include <uapi/linux/mount.h> 92 #include <linux/fsnotify.h> 93 #include <linux/fanotify.h> 94 #include <linux/io_uring.h> 95 96 #include "avc.h" 97 #include "objsec.h" 98 #include "netif.h" 99 #include "netnode.h" 100 #include "netport.h" 101 #include "ibpkey.h" 102 #include "xfrm.h" 103 #include "netlabel.h" 104 #include "audit.h" 105 #include "avc_ss.h" 106 107 #define SELINUX_INODE_INIT_XATTRS 1 108 109 struct selinux_state selinux_state; 110 111 /* SECMARK reference count */ 112 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 113 114 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 115 static int selinux_enforcing_boot __initdata; 116 117 static int __init enforcing_setup(char *str) 118 { 119 unsigned long enforcing; 120 if (!kstrtoul(str, 0, &enforcing)) 121 selinux_enforcing_boot = enforcing ? 1 : 0; 122 return 1; 123 } 124 __setup("enforcing=", enforcing_setup); 125 #else 126 #define selinux_enforcing_boot 1 127 #endif 128 129 int selinux_enabled_boot __initdata = 1; 130 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 131 static int __init selinux_enabled_setup(char *str) 132 { 133 unsigned long enabled; 134 if (!kstrtoul(str, 0, &enabled)) 135 selinux_enabled_boot = enabled ? 1 : 0; 136 return 1; 137 } 138 __setup("selinux=", selinux_enabled_setup); 139 #endif 140 141 static int __init checkreqprot_setup(char *str) 142 { 143 unsigned long checkreqprot; 144 145 if (!kstrtoul(str, 0, &checkreqprot)) { 146 if (checkreqprot) 147 pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n"); 148 } 149 return 1; 150 } 151 __setup("checkreqprot=", checkreqprot_setup); 152 153 /** 154 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 155 * 156 * Description: 157 * This function checks the SECMARK reference counter to see if any SECMARK 158 * targets are currently configured, if the reference counter is greater than 159 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 160 * enabled, false (0) if SECMARK is disabled. If the always_check_network 161 * policy capability is enabled, SECMARK is always considered enabled. 162 * 163 */ 164 static int selinux_secmark_enabled(void) 165 { 166 return (selinux_policycap_alwaysnetwork() || 167 atomic_read(&selinux_secmark_refcount)); 168 } 169 170 /** 171 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 172 * 173 * Description: 174 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 175 * (1) if any are enabled or false (0) if neither are enabled. If the 176 * always_check_network policy capability is enabled, peer labeling 177 * is always considered enabled. 178 * 179 */ 180 static int selinux_peerlbl_enabled(void) 181 { 182 return (selinux_policycap_alwaysnetwork() || 183 netlbl_enabled() || selinux_xfrm_enabled()); 184 } 185 186 static int selinux_netcache_avc_callback(u32 event) 187 { 188 if (event == AVC_CALLBACK_RESET) { 189 sel_netif_flush(); 190 sel_netnode_flush(); 191 sel_netport_flush(); 192 synchronize_net(); 193 } 194 return 0; 195 } 196 197 static int selinux_lsm_notifier_avc_callback(u32 event) 198 { 199 if (event == AVC_CALLBACK_RESET) { 200 sel_ib_pkey_flush(); 201 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 202 } 203 204 return 0; 205 } 206 207 /* 208 * initialise the security for the init task 209 */ 210 static void cred_init_security(void) 211 { 212 struct task_security_struct *tsec; 213 214 tsec = selinux_cred(unrcu_pointer(current->real_cred)); 215 tsec->osid = tsec->sid = SECINITSID_KERNEL; 216 } 217 218 /* 219 * get the security ID of a set of credentials 220 */ 221 static inline u32 cred_sid(const struct cred *cred) 222 { 223 const struct task_security_struct *tsec; 224 225 tsec = selinux_cred(cred); 226 return tsec->sid; 227 } 228 229 static void __ad_net_init(struct common_audit_data *ad, 230 struct lsm_network_audit *net, 231 int ifindex, struct sock *sk, u16 family) 232 { 233 ad->type = LSM_AUDIT_DATA_NET; 234 ad->u.net = net; 235 net->netif = ifindex; 236 net->sk = sk; 237 net->family = family; 238 } 239 240 static void ad_net_init_from_sk(struct common_audit_data *ad, 241 struct lsm_network_audit *net, 242 struct sock *sk) 243 { 244 __ad_net_init(ad, net, 0, sk, 0); 245 } 246 247 static void ad_net_init_from_iif(struct common_audit_data *ad, 248 struct lsm_network_audit *net, 249 int ifindex, u16 family) 250 { 251 __ad_net_init(ad, net, ifindex, NULL, family); 252 } 253 254 /* 255 * get the objective security ID of a task 256 */ 257 static inline u32 task_sid_obj(const struct task_struct *task) 258 { 259 u32 sid; 260 261 rcu_read_lock(); 262 sid = cred_sid(__task_cred(task)); 263 rcu_read_unlock(); 264 return sid; 265 } 266 267 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 268 269 /* 270 * Try reloading inode security labels that have been marked as invalid. The 271 * @may_sleep parameter indicates when sleeping and thus reloading labels is 272 * allowed; when set to false, returns -ECHILD when the label is 273 * invalid. The @dentry parameter should be set to a dentry of the inode. 274 */ 275 static int __inode_security_revalidate(struct inode *inode, 276 struct dentry *dentry, 277 bool may_sleep) 278 { 279 struct inode_security_struct *isec = selinux_inode(inode); 280 281 might_sleep_if(may_sleep); 282 283 if (selinux_initialized() && 284 isec->initialized != LABEL_INITIALIZED) { 285 if (!may_sleep) 286 return -ECHILD; 287 288 /* 289 * Try reloading the inode security label. This will fail if 290 * @opt_dentry is NULL and no dentry for this inode can be 291 * found; in that case, continue using the old label. 292 */ 293 inode_doinit_with_dentry(inode, dentry); 294 } 295 return 0; 296 } 297 298 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 299 { 300 return selinux_inode(inode); 301 } 302 303 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 304 { 305 int error; 306 307 error = __inode_security_revalidate(inode, NULL, !rcu); 308 if (error) 309 return ERR_PTR(error); 310 return selinux_inode(inode); 311 } 312 313 /* 314 * Get the security label of an inode. 315 */ 316 static struct inode_security_struct *inode_security(struct inode *inode) 317 { 318 __inode_security_revalidate(inode, NULL, true); 319 return selinux_inode(inode); 320 } 321 322 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 323 { 324 struct inode *inode = d_backing_inode(dentry); 325 326 return selinux_inode(inode); 327 } 328 329 /* 330 * Get the security label of a dentry's backing inode. 331 */ 332 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 333 { 334 struct inode *inode = d_backing_inode(dentry); 335 336 __inode_security_revalidate(inode, dentry, true); 337 return selinux_inode(inode); 338 } 339 340 static void inode_free_security(struct inode *inode) 341 { 342 struct inode_security_struct *isec = selinux_inode(inode); 343 struct superblock_security_struct *sbsec; 344 345 if (!isec) 346 return; 347 sbsec = selinux_superblock(inode->i_sb); 348 /* 349 * As not all inode security structures are in a list, we check for 350 * empty list outside of the lock to make sure that we won't waste 351 * time taking a lock doing nothing. 352 * 353 * The list_del_init() function can be safely called more than once. 354 * It should not be possible for this function to be called with 355 * concurrent list_add(), but for better safety against future changes 356 * in the code, we use list_empty_careful() here. 357 */ 358 if (!list_empty_careful(&isec->list)) { 359 spin_lock(&sbsec->isec_lock); 360 list_del_init(&isec->list); 361 spin_unlock(&sbsec->isec_lock); 362 } 363 } 364 365 struct selinux_mnt_opts { 366 u32 fscontext_sid; 367 u32 context_sid; 368 u32 rootcontext_sid; 369 u32 defcontext_sid; 370 }; 371 372 static void selinux_free_mnt_opts(void *mnt_opts) 373 { 374 kfree(mnt_opts); 375 } 376 377 enum { 378 Opt_error = -1, 379 Opt_context = 0, 380 Opt_defcontext = 1, 381 Opt_fscontext = 2, 382 Opt_rootcontext = 3, 383 Opt_seclabel = 4, 384 }; 385 386 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 387 static const struct { 388 const char *name; 389 int len; 390 int opt; 391 bool has_arg; 392 } tokens[] = { 393 A(context, true), 394 A(fscontext, true), 395 A(defcontext, true), 396 A(rootcontext, true), 397 A(seclabel, false), 398 }; 399 #undef A 400 401 static int match_opt_prefix(char *s, int l, char **arg) 402 { 403 int i; 404 405 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 406 size_t len = tokens[i].len; 407 if (len > l || memcmp(s, tokens[i].name, len)) 408 continue; 409 if (tokens[i].has_arg) { 410 if (len == l || s[len] != '=') 411 continue; 412 *arg = s + len + 1; 413 } else if (len != l) 414 continue; 415 return tokens[i].opt; 416 } 417 return Opt_error; 418 } 419 420 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 421 422 static int may_context_mount_sb_relabel(u32 sid, 423 struct superblock_security_struct *sbsec, 424 const struct cred *cred) 425 { 426 const struct task_security_struct *tsec = selinux_cred(cred); 427 int rc; 428 429 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 430 FILESYSTEM__RELABELFROM, NULL); 431 if (rc) 432 return rc; 433 434 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 435 FILESYSTEM__RELABELTO, NULL); 436 return rc; 437 } 438 439 static int may_context_mount_inode_relabel(u32 sid, 440 struct superblock_security_struct *sbsec, 441 const struct cred *cred) 442 { 443 const struct task_security_struct *tsec = selinux_cred(cred); 444 int rc; 445 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 446 FILESYSTEM__RELABELFROM, NULL); 447 if (rc) 448 return rc; 449 450 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 451 FILESYSTEM__ASSOCIATE, NULL); 452 return rc; 453 } 454 455 static int selinux_is_genfs_special_handling(struct super_block *sb) 456 { 457 /* Special handling. Genfs but also in-core setxattr handler */ 458 return !strcmp(sb->s_type->name, "sysfs") || 459 !strcmp(sb->s_type->name, "pstore") || 460 !strcmp(sb->s_type->name, "debugfs") || 461 !strcmp(sb->s_type->name, "tracefs") || 462 !strcmp(sb->s_type->name, "rootfs") || 463 (selinux_policycap_cgroupseclabel() && 464 (!strcmp(sb->s_type->name, "cgroup") || 465 !strcmp(sb->s_type->name, "cgroup2"))); 466 } 467 468 static int selinux_is_sblabel_mnt(struct super_block *sb) 469 { 470 struct superblock_security_struct *sbsec = selinux_superblock(sb); 471 472 /* 473 * IMPORTANT: Double-check logic in this function when adding a new 474 * SECURITY_FS_USE_* definition! 475 */ 476 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 477 478 switch (sbsec->behavior) { 479 case SECURITY_FS_USE_XATTR: 480 case SECURITY_FS_USE_TRANS: 481 case SECURITY_FS_USE_TASK: 482 case SECURITY_FS_USE_NATIVE: 483 return 1; 484 485 case SECURITY_FS_USE_GENFS: 486 return selinux_is_genfs_special_handling(sb); 487 488 /* Never allow relabeling on context mounts */ 489 case SECURITY_FS_USE_MNTPOINT: 490 case SECURITY_FS_USE_NONE: 491 default: 492 return 0; 493 } 494 } 495 496 static int sb_check_xattr_support(struct super_block *sb) 497 { 498 struct superblock_security_struct *sbsec = selinux_superblock(sb); 499 struct dentry *root = sb->s_root; 500 struct inode *root_inode = d_backing_inode(root); 501 u32 sid; 502 int rc; 503 504 /* 505 * Make sure that the xattr handler exists and that no 506 * error other than -ENODATA is returned by getxattr on 507 * the root directory. -ENODATA is ok, as this may be 508 * the first boot of the SELinux kernel before we have 509 * assigned xattr values to the filesystem. 510 */ 511 if (!(root_inode->i_opflags & IOP_XATTR)) { 512 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", 513 sb->s_id, sb->s_type->name); 514 goto fallback; 515 } 516 517 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 518 if (rc < 0 && rc != -ENODATA) { 519 if (rc == -EOPNOTSUPP) { 520 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", 521 sb->s_id, sb->s_type->name); 522 goto fallback; 523 } else { 524 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", 525 sb->s_id, sb->s_type->name, -rc); 526 return rc; 527 } 528 } 529 return 0; 530 531 fallback: 532 /* No xattr support - try to fallback to genfs if possible. */ 533 rc = security_genfs_sid(sb->s_type->name, "/", 534 SECCLASS_DIR, &sid); 535 if (rc) 536 return -EOPNOTSUPP; 537 538 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", 539 sb->s_id, sb->s_type->name); 540 sbsec->behavior = SECURITY_FS_USE_GENFS; 541 sbsec->sid = sid; 542 return 0; 543 } 544 545 static int sb_finish_set_opts(struct super_block *sb) 546 { 547 struct superblock_security_struct *sbsec = selinux_superblock(sb); 548 struct dentry *root = sb->s_root; 549 struct inode *root_inode = d_backing_inode(root); 550 int rc = 0; 551 552 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 553 rc = sb_check_xattr_support(sb); 554 if (rc) 555 return rc; 556 } 557 558 sbsec->flags |= SE_SBINITIALIZED; 559 560 /* 561 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 562 * leave the flag untouched because sb_clone_mnt_opts might be handing 563 * us a superblock that needs the flag to be cleared. 564 */ 565 if (selinux_is_sblabel_mnt(sb)) 566 sbsec->flags |= SBLABEL_MNT; 567 else 568 sbsec->flags &= ~SBLABEL_MNT; 569 570 /* Initialize the root inode. */ 571 rc = inode_doinit_with_dentry(root_inode, root); 572 573 /* Initialize any other inodes associated with the superblock, e.g. 574 inodes created prior to initial policy load or inodes created 575 during get_sb by a pseudo filesystem that directly 576 populates itself. */ 577 spin_lock(&sbsec->isec_lock); 578 while (!list_empty(&sbsec->isec_head)) { 579 struct inode_security_struct *isec = 580 list_first_entry(&sbsec->isec_head, 581 struct inode_security_struct, list); 582 struct inode *inode = isec->inode; 583 list_del_init(&isec->list); 584 spin_unlock(&sbsec->isec_lock); 585 inode = igrab(inode); 586 if (inode) { 587 if (!IS_PRIVATE(inode)) 588 inode_doinit_with_dentry(inode, NULL); 589 iput(inode); 590 } 591 spin_lock(&sbsec->isec_lock); 592 } 593 spin_unlock(&sbsec->isec_lock); 594 return rc; 595 } 596 597 static int bad_option(struct superblock_security_struct *sbsec, char flag, 598 u32 old_sid, u32 new_sid) 599 { 600 char mnt_flags = sbsec->flags & SE_MNTMASK; 601 602 /* check if the old mount command had the same options */ 603 if (sbsec->flags & SE_SBINITIALIZED) 604 if (!(sbsec->flags & flag) || 605 (old_sid != new_sid)) 606 return 1; 607 608 /* check if we were passed the same options twice, 609 * aka someone passed context=a,context=b 610 */ 611 if (!(sbsec->flags & SE_SBINITIALIZED)) 612 if (mnt_flags & flag) 613 return 1; 614 return 0; 615 } 616 617 /* 618 * Allow filesystems with binary mount data to explicitly set mount point 619 * labeling information. 620 */ 621 static int selinux_set_mnt_opts(struct super_block *sb, 622 void *mnt_opts, 623 unsigned long kern_flags, 624 unsigned long *set_kern_flags) 625 { 626 const struct cred *cred = current_cred(); 627 struct superblock_security_struct *sbsec = selinux_superblock(sb); 628 struct dentry *root = sb->s_root; 629 struct selinux_mnt_opts *opts = mnt_opts; 630 struct inode_security_struct *root_isec; 631 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 632 u32 defcontext_sid = 0; 633 int rc = 0; 634 635 /* 636 * Specifying internal flags without providing a place to 637 * place the results is not allowed 638 */ 639 if (kern_flags && !set_kern_flags) 640 return -EINVAL; 641 642 mutex_lock(&sbsec->lock); 643 644 if (!selinux_initialized()) { 645 if (!opts) { 646 /* Defer initialization until selinux_complete_init, 647 after the initial policy is loaded and the security 648 server is ready to handle calls. */ 649 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 650 sbsec->flags |= SE_SBNATIVE; 651 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 652 } 653 goto out; 654 } 655 rc = -EINVAL; 656 pr_warn("SELinux: Unable to set superblock options " 657 "before the security server is initialized\n"); 658 goto out; 659 } 660 661 /* 662 * Binary mount data FS will come through this function twice. Once 663 * from an explicit call and once from the generic calls from the vfs. 664 * Since the generic VFS calls will not contain any security mount data 665 * we need to skip the double mount verification. 666 * 667 * This does open a hole in which we will not notice if the first 668 * mount using this sb set explicit options and a second mount using 669 * this sb does not set any security options. (The first options 670 * will be used for both mounts) 671 */ 672 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 673 && !opts) 674 goto out; 675 676 root_isec = backing_inode_security_novalidate(root); 677 678 /* 679 * parse the mount options, check if they are valid sids. 680 * also check if someone is trying to mount the same sb more 681 * than once with different security options. 682 */ 683 if (opts) { 684 if (opts->fscontext_sid) { 685 fscontext_sid = opts->fscontext_sid; 686 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 687 fscontext_sid)) 688 goto out_double_mount; 689 sbsec->flags |= FSCONTEXT_MNT; 690 } 691 if (opts->context_sid) { 692 context_sid = opts->context_sid; 693 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 694 context_sid)) 695 goto out_double_mount; 696 sbsec->flags |= CONTEXT_MNT; 697 } 698 if (opts->rootcontext_sid) { 699 rootcontext_sid = opts->rootcontext_sid; 700 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 701 rootcontext_sid)) 702 goto out_double_mount; 703 sbsec->flags |= ROOTCONTEXT_MNT; 704 } 705 if (opts->defcontext_sid) { 706 defcontext_sid = opts->defcontext_sid; 707 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 708 defcontext_sid)) 709 goto out_double_mount; 710 sbsec->flags |= DEFCONTEXT_MNT; 711 } 712 } 713 714 if (sbsec->flags & SE_SBINITIALIZED) { 715 /* previously mounted with options, but not on this attempt? */ 716 if ((sbsec->flags & SE_MNTMASK) && !opts) 717 goto out_double_mount; 718 rc = 0; 719 goto out; 720 } 721 722 if (strcmp(sb->s_type->name, "proc") == 0) 723 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 724 725 if (!strcmp(sb->s_type->name, "debugfs") || 726 !strcmp(sb->s_type->name, "tracefs") || 727 !strcmp(sb->s_type->name, "binder") || 728 !strcmp(sb->s_type->name, "bpf") || 729 !strcmp(sb->s_type->name, "pstore") || 730 !strcmp(sb->s_type->name, "securityfs")) 731 sbsec->flags |= SE_SBGENFS; 732 733 if (!strcmp(sb->s_type->name, "sysfs") || 734 !strcmp(sb->s_type->name, "cgroup") || 735 !strcmp(sb->s_type->name, "cgroup2")) 736 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 737 738 if (!sbsec->behavior) { 739 /* 740 * Determine the labeling behavior to use for this 741 * filesystem type. 742 */ 743 rc = security_fs_use(sb); 744 if (rc) { 745 pr_warn("%s: security_fs_use(%s) returned %d\n", 746 __func__, sb->s_type->name, rc); 747 goto out; 748 } 749 } 750 751 /* 752 * If this is a user namespace mount and the filesystem type is not 753 * explicitly whitelisted, then no contexts are allowed on the command 754 * line and security labels must be ignored. 755 */ 756 if (sb->s_user_ns != &init_user_ns && 757 strcmp(sb->s_type->name, "tmpfs") && 758 strcmp(sb->s_type->name, "ramfs") && 759 strcmp(sb->s_type->name, "devpts") && 760 strcmp(sb->s_type->name, "overlay")) { 761 if (context_sid || fscontext_sid || rootcontext_sid || 762 defcontext_sid) { 763 rc = -EACCES; 764 goto out; 765 } 766 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 767 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 768 rc = security_transition_sid(current_sid(), 769 current_sid(), 770 SECCLASS_FILE, NULL, 771 &sbsec->mntpoint_sid); 772 if (rc) 773 goto out; 774 } 775 goto out_set_opts; 776 } 777 778 /* sets the context of the superblock for the fs being mounted. */ 779 if (fscontext_sid) { 780 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 781 if (rc) 782 goto out; 783 784 sbsec->sid = fscontext_sid; 785 } 786 787 /* 788 * Switch to using mount point labeling behavior. 789 * sets the label used on all file below the mountpoint, and will set 790 * the superblock context if not already set. 791 */ 792 if (sbsec->flags & SE_SBNATIVE) { 793 /* 794 * This means we are initializing a superblock that has been 795 * mounted before the SELinux was initialized and the 796 * filesystem requested native labeling. We had already 797 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags 798 * in the original mount attempt, so now we just need to set 799 * the SECURITY_FS_USE_NATIVE behavior. 800 */ 801 sbsec->behavior = SECURITY_FS_USE_NATIVE; 802 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 803 sbsec->behavior = SECURITY_FS_USE_NATIVE; 804 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 805 } 806 807 if (context_sid) { 808 if (!fscontext_sid) { 809 rc = may_context_mount_sb_relabel(context_sid, sbsec, 810 cred); 811 if (rc) 812 goto out; 813 sbsec->sid = context_sid; 814 } else { 815 rc = may_context_mount_inode_relabel(context_sid, sbsec, 816 cred); 817 if (rc) 818 goto out; 819 } 820 if (!rootcontext_sid) 821 rootcontext_sid = context_sid; 822 823 sbsec->mntpoint_sid = context_sid; 824 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 825 } 826 827 if (rootcontext_sid) { 828 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 829 cred); 830 if (rc) 831 goto out; 832 833 root_isec->sid = rootcontext_sid; 834 root_isec->initialized = LABEL_INITIALIZED; 835 } 836 837 if (defcontext_sid) { 838 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 839 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 840 rc = -EINVAL; 841 pr_warn("SELinux: defcontext option is " 842 "invalid for this filesystem type\n"); 843 goto out; 844 } 845 846 if (defcontext_sid != sbsec->def_sid) { 847 rc = may_context_mount_inode_relabel(defcontext_sid, 848 sbsec, cred); 849 if (rc) 850 goto out; 851 } 852 853 sbsec->def_sid = defcontext_sid; 854 } 855 856 out_set_opts: 857 rc = sb_finish_set_opts(sb); 858 out: 859 mutex_unlock(&sbsec->lock); 860 return rc; 861 out_double_mount: 862 rc = -EINVAL; 863 pr_warn("SELinux: mount invalid. Same superblock, different " 864 "security settings for (dev %s, type %s)\n", sb->s_id, 865 sb->s_type->name); 866 goto out; 867 } 868 869 static int selinux_cmp_sb_context(const struct super_block *oldsb, 870 const struct super_block *newsb) 871 { 872 struct superblock_security_struct *old = selinux_superblock(oldsb); 873 struct superblock_security_struct *new = selinux_superblock(newsb); 874 char oldflags = old->flags & SE_MNTMASK; 875 char newflags = new->flags & SE_MNTMASK; 876 877 if (oldflags != newflags) 878 goto mismatch; 879 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 880 goto mismatch; 881 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 882 goto mismatch; 883 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 884 goto mismatch; 885 if (oldflags & ROOTCONTEXT_MNT) { 886 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 887 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 888 if (oldroot->sid != newroot->sid) 889 goto mismatch; 890 } 891 return 0; 892 mismatch: 893 pr_warn("SELinux: mount invalid. Same superblock, " 894 "different security settings for (dev %s, " 895 "type %s)\n", newsb->s_id, newsb->s_type->name); 896 return -EBUSY; 897 } 898 899 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 900 struct super_block *newsb, 901 unsigned long kern_flags, 902 unsigned long *set_kern_flags) 903 { 904 int rc = 0; 905 const struct superblock_security_struct *oldsbsec = 906 selinux_superblock(oldsb); 907 struct superblock_security_struct *newsbsec = selinux_superblock(newsb); 908 909 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 910 int set_context = (oldsbsec->flags & CONTEXT_MNT); 911 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 912 913 /* 914 * Specifying internal flags without providing a place to 915 * place the results is not allowed. 916 */ 917 if (kern_flags && !set_kern_flags) 918 return -EINVAL; 919 920 mutex_lock(&newsbsec->lock); 921 922 /* 923 * if the parent was able to be mounted it clearly had no special lsm 924 * mount options. thus we can safely deal with this superblock later 925 */ 926 if (!selinux_initialized()) { 927 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 928 newsbsec->flags |= SE_SBNATIVE; 929 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 930 } 931 goto out; 932 } 933 934 /* how can we clone if the old one wasn't set up?? */ 935 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 936 937 /* if fs is reusing a sb, make sure that the contexts match */ 938 if (newsbsec->flags & SE_SBINITIALIZED) { 939 mutex_unlock(&newsbsec->lock); 940 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 941 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 942 return selinux_cmp_sb_context(oldsb, newsb); 943 } 944 945 newsbsec->flags = oldsbsec->flags; 946 947 newsbsec->sid = oldsbsec->sid; 948 newsbsec->def_sid = oldsbsec->def_sid; 949 newsbsec->behavior = oldsbsec->behavior; 950 951 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 952 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 953 rc = security_fs_use(newsb); 954 if (rc) 955 goto out; 956 } 957 958 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 959 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 960 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 961 } 962 963 if (set_context) { 964 u32 sid = oldsbsec->mntpoint_sid; 965 966 if (!set_fscontext) 967 newsbsec->sid = sid; 968 if (!set_rootcontext) { 969 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 970 newisec->sid = sid; 971 } 972 newsbsec->mntpoint_sid = sid; 973 } 974 if (set_rootcontext) { 975 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 976 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 977 978 newisec->sid = oldisec->sid; 979 } 980 981 sb_finish_set_opts(newsb); 982 out: 983 mutex_unlock(&newsbsec->lock); 984 return rc; 985 } 986 987 /* 988 * NOTE: the caller is responsible for freeing the memory even if on error. 989 */ 990 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 991 { 992 struct selinux_mnt_opts *opts = *mnt_opts; 993 u32 *dst_sid; 994 int rc; 995 996 if (token == Opt_seclabel) 997 /* eaten and completely ignored */ 998 return 0; 999 if (!s) 1000 return -EINVAL; 1001 1002 if (!selinux_initialized()) { 1003 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); 1004 return -EINVAL; 1005 } 1006 1007 if (!opts) { 1008 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 1009 if (!opts) 1010 return -ENOMEM; 1011 *mnt_opts = opts; 1012 } 1013 1014 switch (token) { 1015 case Opt_context: 1016 if (opts->context_sid || opts->defcontext_sid) 1017 goto err; 1018 dst_sid = &opts->context_sid; 1019 break; 1020 case Opt_fscontext: 1021 if (opts->fscontext_sid) 1022 goto err; 1023 dst_sid = &opts->fscontext_sid; 1024 break; 1025 case Opt_rootcontext: 1026 if (opts->rootcontext_sid) 1027 goto err; 1028 dst_sid = &opts->rootcontext_sid; 1029 break; 1030 case Opt_defcontext: 1031 if (opts->context_sid || opts->defcontext_sid) 1032 goto err; 1033 dst_sid = &opts->defcontext_sid; 1034 break; 1035 default: 1036 WARN_ON(1); 1037 return -EINVAL; 1038 } 1039 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); 1040 if (rc) 1041 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", 1042 s, rc); 1043 return rc; 1044 1045 err: 1046 pr_warn(SEL_MOUNT_FAIL_MSG); 1047 return -EINVAL; 1048 } 1049 1050 static int show_sid(struct seq_file *m, u32 sid) 1051 { 1052 char *context = NULL; 1053 u32 len; 1054 int rc; 1055 1056 rc = security_sid_to_context(sid, &context, &len); 1057 if (!rc) { 1058 bool has_comma = strchr(context, ','); 1059 1060 seq_putc(m, '='); 1061 if (has_comma) 1062 seq_putc(m, '\"'); 1063 seq_escape(m, context, "\"\n\\"); 1064 if (has_comma) 1065 seq_putc(m, '\"'); 1066 } 1067 kfree(context); 1068 return rc; 1069 } 1070 1071 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1072 { 1073 struct superblock_security_struct *sbsec = selinux_superblock(sb); 1074 int rc; 1075 1076 if (!(sbsec->flags & SE_SBINITIALIZED)) 1077 return 0; 1078 1079 if (!selinux_initialized()) 1080 return 0; 1081 1082 if (sbsec->flags & FSCONTEXT_MNT) { 1083 seq_putc(m, ','); 1084 seq_puts(m, FSCONTEXT_STR); 1085 rc = show_sid(m, sbsec->sid); 1086 if (rc) 1087 return rc; 1088 } 1089 if (sbsec->flags & CONTEXT_MNT) { 1090 seq_putc(m, ','); 1091 seq_puts(m, CONTEXT_STR); 1092 rc = show_sid(m, sbsec->mntpoint_sid); 1093 if (rc) 1094 return rc; 1095 } 1096 if (sbsec->flags & DEFCONTEXT_MNT) { 1097 seq_putc(m, ','); 1098 seq_puts(m, DEFCONTEXT_STR); 1099 rc = show_sid(m, sbsec->def_sid); 1100 if (rc) 1101 return rc; 1102 } 1103 if (sbsec->flags & ROOTCONTEXT_MNT) { 1104 struct dentry *root = sb->s_root; 1105 struct inode_security_struct *isec = backing_inode_security(root); 1106 seq_putc(m, ','); 1107 seq_puts(m, ROOTCONTEXT_STR); 1108 rc = show_sid(m, isec->sid); 1109 if (rc) 1110 return rc; 1111 } 1112 if (sbsec->flags & SBLABEL_MNT) { 1113 seq_putc(m, ','); 1114 seq_puts(m, SECLABEL_STR); 1115 } 1116 return 0; 1117 } 1118 1119 static inline u16 inode_mode_to_security_class(umode_t mode) 1120 { 1121 switch (mode & S_IFMT) { 1122 case S_IFSOCK: 1123 return SECCLASS_SOCK_FILE; 1124 case S_IFLNK: 1125 return SECCLASS_LNK_FILE; 1126 case S_IFREG: 1127 return SECCLASS_FILE; 1128 case S_IFBLK: 1129 return SECCLASS_BLK_FILE; 1130 case S_IFDIR: 1131 return SECCLASS_DIR; 1132 case S_IFCHR: 1133 return SECCLASS_CHR_FILE; 1134 case S_IFIFO: 1135 return SECCLASS_FIFO_FILE; 1136 1137 } 1138 1139 return SECCLASS_FILE; 1140 } 1141 1142 static inline int default_protocol_stream(int protocol) 1143 { 1144 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || 1145 protocol == IPPROTO_MPTCP); 1146 } 1147 1148 static inline int default_protocol_dgram(int protocol) 1149 { 1150 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1151 } 1152 1153 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1154 { 1155 bool extsockclass = selinux_policycap_extsockclass(); 1156 1157 switch (family) { 1158 case PF_UNIX: 1159 switch (type) { 1160 case SOCK_STREAM: 1161 case SOCK_SEQPACKET: 1162 return SECCLASS_UNIX_STREAM_SOCKET; 1163 case SOCK_DGRAM: 1164 case SOCK_RAW: 1165 return SECCLASS_UNIX_DGRAM_SOCKET; 1166 } 1167 break; 1168 case PF_INET: 1169 case PF_INET6: 1170 switch (type) { 1171 case SOCK_STREAM: 1172 case SOCK_SEQPACKET: 1173 if (default_protocol_stream(protocol)) 1174 return SECCLASS_TCP_SOCKET; 1175 else if (extsockclass && protocol == IPPROTO_SCTP) 1176 return SECCLASS_SCTP_SOCKET; 1177 else 1178 return SECCLASS_RAWIP_SOCKET; 1179 case SOCK_DGRAM: 1180 if (default_protocol_dgram(protocol)) 1181 return SECCLASS_UDP_SOCKET; 1182 else if (extsockclass && (protocol == IPPROTO_ICMP || 1183 protocol == IPPROTO_ICMPV6)) 1184 return SECCLASS_ICMP_SOCKET; 1185 else 1186 return SECCLASS_RAWIP_SOCKET; 1187 case SOCK_DCCP: 1188 return SECCLASS_DCCP_SOCKET; 1189 default: 1190 return SECCLASS_RAWIP_SOCKET; 1191 } 1192 break; 1193 case PF_NETLINK: 1194 switch (protocol) { 1195 case NETLINK_ROUTE: 1196 return SECCLASS_NETLINK_ROUTE_SOCKET; 1197 case NETLINK_SOCK_DIAG: 1198 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1199 case NETLINK_NFLOG: 1200 return SECCLASS_NETLINK_NFLOG_SOCKET; 1201 case NETLINK_XFRM: 1202 return SECCLASS_NETLINK_XFRM_SOCKET; 1203 case NETLINK_SELINUX: 1204 return SECCLASS_NETLINK_SELINUX_SOCKET; 1205 case NETLINK_ISCSI: 1206 return SECCLASS_NETLINK_ISCSI_SOCKET; 1207 case NETLINK_AUDIT: 1208 return SECCLASS_NETLINK_AUDIT_SOCKET; 1209 case NETLINK_FIB_LOOKUP: 1210 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1211 case NETLINK_CONNECTOR: 1212 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1213 case NETLINK_NETFILTER: 1214 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1215 case NETLINK_DNRTMSG: 1216 return SECCLASS_NETLINK_DNRT_SOCKET; 1217 case NETLINK_KOBJECT_UEVENT: 1218 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1219 case NETLINK_GENERIC: 1220 return SECCLASS_NETLINK_GENERIC_SOCKET; 1221 case NETLINK_SCSITRANSPORT: 1222 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1223 case NETLINK_RDMA: 1224 return SECCLASS_NETLINK_RDMA_SOCKET; 1225 case NETLINK_CRYPTO: 1226 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1227 default: 1228 return SECCLASS_NETLINK_SOCKET; 1229 } 1230 case PF_PACKET: 1231 return SECCLASS_PACKET_SOCKET; 1232 case PF_KEY: 1233 return SECCLASS_KEY_SOCKET; 1234 case PF_APPLETALK: 1235 return SECCLASS_APPLETALK_SOCKET; 1236 } 1237 1238 if (extsockclass) { 1239 switch (family) { 1240 case PF_AX25: 1241 return SECCLASS_AX25_SOCKET; 1242 case PF_IPX: 1243 return SECCLASS_IPX_SOCKET; 1244 case PF_NETROM: 1245 return SECCLASS_NETROM_SOCKET; 1246 case PF_ATMPVC: 1247 return SECCLASS_ATMPVC_SOCKET; 1248 case PF_X25: 1249 return SECCLASS_X25_SOCKET; 1250 case PF_ROSE: 1251 return SECCLASS_ROSE_SOCKET; 1252 case PF_DECnet: 1253 return SECCLASS_DECNET_SOCKET; 1254 case PF_ATMSVC: 1255 return SECCLASS_ATMSVC_SOCKET; 1256 case PF_RDS: 1257 return SECCLASS_RDS_SOCKET; 1258 case PF_IRDA: 1259 return SECCLASS_IRDA_SOCKET; 1260 case PF_PPPOX: 1261 return SECCLASS_PPPOX_SOCKET; 1262 case PF_LLC: 1263 return SECCLASS_LLC_SOCKET; 1264 case PF_CAN: 1265 return SECCLASS_CAN_SOCKET; 1266 case PF_TIPC: 1267 return SECCLASS_TIPC_SOCKET; 1268 case PF_BLUETOOTH: 1269 return SECCLASS_BLUETOOTH_SOCKET; 1270 case PF_IUCV: 1271 return SECCLASS_IUCV_SOCKET; 1272 case PF_RXRPC: 1273 return SECCLASS_RXRPC_SOCKET; 1274 case PF_ISDN: 1275 return SECCLASS_ISDN_SOCKET; 1276 case PF_PHONET: 1277 return SECCLASS_PHONET_SOCKET; 1278 case PF_IEEE802154: 1279 return SECCLASS_IEEE802154_SOCKET; 1280 case PF_CAIF: 1281 return SECCLASS_CAIF_SOCKET; 1282 case PF_ALG: 1283 return SECCLASS_ALG_SOCKET; 1284 case PF_NFC: 1285 return SECCLASS_NFC_SOCKET; 1286 case PF_VSOCK: 1287 return SECCLASS_VSOCK_SOCKET; 1288 case PF_KCM: 1289 return SECCLASS_KCM_SOCKET; 1290 case PF_QIPCRTR: 1291 return SECCLASS_QIPCRTR_SOCKET; 1292 case PF_SMC: 1293 return SECCLASS_SMC_SOCKET; 1294 case PF_XDP: 1295 return SECCLASS_XDP_SOCKET; 1296 case PF_MCTP: 1297 return SECCLASS_MCTP_SOCKET; 1298 #if PF_MAX > 46 1299 #error New address family defined, please update this function. 1300 #endif 1301 } 1302 } 1303 1304 return SECCLASS_SOCKET; 1305 } 1306 1307 static int selinux_genfs_get_sid(struct dentry *dentry, 1308 u16 tclass, 1309 u16 flags, 1310 u32 *sid) 1311 { 1312 int rc; 1313 struct super_block *sb = dentry->d_sb; 1314 char *buffer, *path; 1315 1316 buffer = (char *)__get_free_page(GFP_KERNEL); 1317 if (!buffer) 1318 return -ENOMEM; 1319 1320 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1321 if (IS_ERR(path)) 1322 rc = PTR_ERR(path); 1323 else { 1324 if (flags & SE_SBPROC) { 1325 /* each process gets a /proc/PID/ entry. Strip off the 1326 * PID part to get a valid selinux labeling. 1327 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1328 while (path[1] >= '0' && path[1] <= '9') { 1329 path[1] = '/'; 1330 path++; 1331 } 1332 } 1333 rc = security_genfs_sid(sb->s_type->name, 1334 path, tclass, sid); 1335 if (rc == -ENOENT) { 1336 /* No match in policy, mark as unlabeled. */ 1337 *sid = SECINITSID_UNLABELED; 1338 rc = 0; 1339 } 1340 } 1341 free_page((unsigned long)buffer); 1342 return rc; 1343 } 1344 1345 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1346 u32 def_sid, u32 *sid) 1347 { 1348 #define INITCONTEXTLEN 255 1349 char *context; 1350 unsigned int len; 1351 int rc; 1352 1353 len = INITCONTEXTLEN; 1354 context = kmalloc(len + 1, GFP_NOFS); 1355 if (!context) 1356 return -ENOMEM; 1357 1358 context[len] = '\0'; 1359 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1360 if (rc == -ERANGE) { 1361 kfree(context); 1362 1363 /* Need a larger buffer. Query for the right size. */ 1364 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1365 if (rc < 0) 1366 return rc; 1367 1368 len = rc; 1369 context = kmalloc(len + 1, GFP_NOFS); 1370 if (!context) 1371 return -ENOMEM; 1372 1373 context[len] = '\0'; 1374 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1375 context, len); 1376 } 1377 if (rc < 0) { 1378 kfree(context); 1379 if (rc != -ENODATA) { 1380 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1381 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1382 return rc; 1383 } 1384 *sid = def_sid; 1385 return 0; 1386 } 1387 1388 rc = security_context_to_sid_default(context, rc, sid, 1389 def_sid, GFP_NOFS); 1390 if (rc) { 1391 char *dev = inode->i_sb->s_id; 1392 unsigned long ino = inode->i_ino; 1393 1394 if (rc == -EINVAL) { 1395 pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s. This indicates you may need to relabel the inode or the filesystem in question.\n", 1396 ino, dev, context); 1397 } else { 1398 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1399 __func__, context, -rc, dev, ino); 1400 } 1401 } 1402 kfree(context); 1403 return 0; 1404 } 1405 1406 /* The inode's security attributes must be initialized before first use. */ 1407 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1408 { 1409 struct superblock_security_struct *sbsec = NULL; 1410 struct inode_security_struct *isec = selinux_inode(inode); 1411 u32 task_sid, sid = 0; 1412 u16 sclass; 1413 struct dentry *dentry; 1414 int rc = 0; 1415 1416 if (isec->initialized == LABEL_INITIALIZED) 1417 return 0; 1418 1419 spin_lock(&isec->lock); 1420 if (isec->initialized == LABEL_INITIALIZED) 1421 goto out_unlock; 1422 1423 if (isec->sclass == SECCLASS_FILE) 1424 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1425 1426 sbsec = selinux_superblock(inode->i_sb); 1427 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1428 /* Defer initialization until selinux_complete_init, 1429 after the initial policy is loaded and the security 1430 server is ready to handle calls. */ 1431 spin_lock(&sbsec->isec_lock); 1432 if (list_empty(&isec->list)) 1433 list_add(&isec->list, &sbsec->isec_head); 1434 spin_unlock(&sbsec->isec_lock); 1435 goto out_unlock; 1436 } 1437 1438 sclass = isec->sclass; 1439 task_sid = isec->task_sid; 1440 sid = isec->sid; 1441 isec->initialized = LABEL_PENDING; 1442 spin_unlock(&isec->lock); 1443 1444 switch (sbsec->behavior) { 1445 /* 1446 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels 1447 * via xattr when called from delayed_superblock_init(). 1448 */ 1449 case SECURITY_FS_USE_NATIVE: 1450 case SECURITY_FS_USE_XATTR: 1451 if (!(inode->i_opflags & IOP_XATTR)) { 1452 sid = sbsec->def_sid; 1453 break; 1454 } 1455 /* Need a dentry, since the xattr API requires one. 1456 Life would be simpler if we could just pass the inode. */ 1457 if (opt_dentry) { 1458 /* Called from d_instantiate or d_splice_alias. */ 1459 dentry = dget(opt_dentry); 1460 } else { 1461 /* 1462 * Called from selinux_complete_init, try to find a dentry. 1463 * Some filesystems really want a connected one, so try 1464 * that first. We could split SECURITY_FS_USE_XATTR in 1465 * two, depending upon that... 1466 */ 1467 dentry = d_find_alias(inode); 1468 if (!dentry) 1469 dentry = d_find_any_alias(inode); 1470 } 1471 if (!dentry) { 1472 /* 1473 * this is can be hit on boot when a file is accessed 1474 * before the policy is loaded. When we load policy we 1475 * may find inodes that have no dentry on the 1476 * sbsec->isec_head list. No reason to complain as these 1477 * will get fixed up the next time we go through 1478 * inode_doinit with a dentry, before these inodes could 1479 * be used again by userspace. 1480 */ 1481 goto out_invalid; 1482 } 1483 1484 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1485 &sid); 1486 dput(dentry); 1487 if (rc) 1488 goto out; 1489 break; 1490 case SECURITY_FS_USE_TASK: 1491 sid = task_sid; 1492 break; 1493 case SECURITY_FS_USE_TRANS: 1494 /* Default to the fs SID. */ 1495 sid = sbsec->sid; 1496 1497 /* Try to obtain a transition SID. */ 1498 rc = security_transition_sid(task_sid, sid, 1499 sclass, NULL, &sid); 1500 if (rc) 1501 goto out; 1502 break; 1503 case SECURITY_FS_USE_MNTPOINT: 1504 sid = sbsec->mntpoint_sid; 1505 break; 1506 default: 1507 /* Default to the fs superblock SID. */ 1508 sid = sbsec->sid; 1509 1510 if ((sbsec->flags & SE_SBGENFS) && 1511 (!S_ISLNK(inode->i_mode) || 1512 selinux_policycap_genfs_seclabel_symlinks())) { 1513 /* We must have a dentry to determine the label on 1514 * procfs inodes */ 1515 if (opt_dentry) { 1516 /* Called from d_instantiate or 1517 * d_splice_alias. */ 1518 dentry = dget(opt_dentry); 1519 } else { 1520 /* Called from selinux_complete_init, try to 1521 * find a dentry. Some filesystems really want 1522 * a connected one, so try that first. 1523 */ 1524 dentry = d_find_alias(inode); 1525 if (!dentry) 1526 dentry = d_find_any_alias(inode); 1527 } 1528 /* 1529 * This can be hit on boot when a file is accessed 1530 * before the policy is loaded. When we load policy we 1531 * may find inodes that have no dentry on the 1532 * sbsec->isec_head list. No reason to complain as 1533 * these will get fixed up the next time we go through 1534 * inode_doinit() with a dentry, before these inodes 1535 * could be used again by userspace. 1536 */ 1537 if (!dentry) 1538 goto out_invalid; 1539 rc = selinux_genfs_get_sid(dentry, sclass, 1540 sbsec->flags, &sid); 1541 if (rc) { 1542 dput(dentry); 1543 goto out; 1544 } 1545 1546 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1547 (inode->i_opflags & IOP_XATTR)) { 1548 rc = inode_doinit_use_xattr(inode, dentry, 1549 sid, &sid); 1550 if (rc) { 1551 dput(dentry); 1552 goto out; 1553 } 1554 } 1555 dput(dentry); 1556 } 1557 break; 1558 } 1559 1560 out: 1561 spin_lock(&isec->lock); 1562 if (isec->initialized == LABEL_PENDING) { 1563 if (rc) { 1564 isec->initialized = LABEL_INVALID; 1565 goto out_unlock; 1566 } 1567 isec->initialized = LABEL_INITIALIZED; 1568 isec->sid = sid; 1569 } 1570 1571 out_unlock: 1572 spin_unlock(&isec->lock); 1573 return rc; 1574 1575 out_invalid: 1576 spin_lock(&isec->lock); 1577 if (isec->initialized == LABEL_PENDING) { 1578 isec->initialized = LABEL_INVALID; 1579 isec->sid = sid; 1580 } 1581 spin_unlock(&isec->lock); 1582 return 0; 1583 } 1584 1585 /* Convert a Linux signal to an access vector. */ 1586 static inline u32 signal_to_av(int sig) 1587 { 1588 u32 perm = 0; 1589 1590 switch (sig) { 1591 case SIGCHLD: 1592 /* Commonly granted from child to parent. */ 1593 perm = PROCESS__SIGCHLD; 1594 break; 1595 case SIGKILL: 1596 /* Cannot be caught or ignored */ 1597 perm = PROCESS__SIGKILL; 1598 break; 1599 case SIGSTOP: 1600 /* Cannot be caught or ignored */ 1601 perm = PROCESS__SIGSTOP; 1602 break; 1603 default: 1604 /* All other signals. */ 1605 perm = PROCESS__SIGNAL; 1606 break; 1607 } 1608 1609 return perm; 1610 } 1611 1612 #if CAP_LAST_CAP > 63 1613 #error Fix SELinux to handle capabilities > 63. 1614 #endif 1615 1616 /* Check whether a task is allowed to use a capability. */ 1617 static int cred_has_capability(const struct cred *cred, 1618 int cap, unsigned int opts, bool initns) 1619 { 1620 struct common_audit_data ad; 1621 struct av_decision avd; 1622 u16 sclass; 1623 u32 sid = cred_sid(cred); 1624 u32 av = CAP_TO_MASK(cap); 1625 int rc; 1626 1627 ad.type = LSM_AUDIT_DATA_CAP; 1628 ad.u.cap = cap; 1629 1630 switch (CAP_TO_INDEX(cap)) { 1631 case 0: 1632 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1633 break; 1634 case 1: 1635 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1636 break; 1637 default: 1638 pr_err("SELinux: out of range capability %d\n", cap); 1639 BUG(); 1640 return -EINVAL; 1641 } 1642 1643 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1644 if (!(opts & CAP_OPT_NOAUDIT)) { 1645 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1646 if (rc2) 1647 return rc2; 1648 } 1649 return rc; 1650 } 1651 1652 /* Check whether a task has a particular permission to an inode. 1653 The 'adp' parameter is optional and allows other audit 1654 data to be passed (e.g. the dentry). */ 1655 static int inode_has_perm(const struct cred *cred, 1656 struct inode *inode, 1657 u32 perms, 1658 struct common_audit_data *adp) 1659 { 1660 struct inode_security_struct *isec; 1661 u32 sid; 1662 1663 validate_creds(cred); 1664 1665 if (unlikely(IS_PRIVATE(inode))) 1666 return 0; 1667 1668 sid = cred_sid(cred); 1669 isec = selinux_inode(inode); 1670 1671 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1672 } 1673 1674 /* Same as inode_has_perm, but pass explicit audit data containing 1675 the dentry to help the auditing code to more easily generate the 1676 pathname if needed. */ 1677 static inline int dentry_has_perm(const struct cred *cred, 1678 struct dentry *dentry, 1679 u32 av) 1680 { 1681 struct inode *inode = d_backing_inode(dentry); 1682 struct common_audit_data ad; 1683 1684 ad.type = LSM_AUDIT_DATA_DENTRY; 1685 ad.u.dentry = dentry; 1686 __inode_security_revalidate(inode, dentry, true); 1687 return inode_has_perm(cred, inode, av, &ad); 1688 } 1689 1690 /* Same as inode_has_perm, but pass explicit audit data containing 1691 the path to help the auditing code to more easily generate the 1692 pathname if needed. */ 1693 static inline int path_has_perm(const struct cred *cred, 1694 const struct path *path, 1695 u32 av) 1696 { 1697 struct inode *inode = d_backing_inode(path->dentry); 1698 struct common_audit_data ad; 1699 1700 ad.type = LSM_AUDIT_DATA_PATH; 1701 ad.u.path = *path; 1702 __inode_security_revalidate(inode, path->dentry, true); 1703 return inode_has_perm(cred, inode, av, &ad); 1704 } 1705 1706 /* Same as path_has_perm, but uses the inode from the file struct. */ 1707 static inline int file_path_has_perm(const struct cred *cred, 1708 struct file *file, 1709 u32 av) 1710 { 1711 struct common_audit_data ad; 1712 1713 ad.type = LSM_AUDIT_DATA_FILE; 1714 ad.u.file = file; 1715 return inode_has_perm(cred, file_inode(file), av, &ad); 1716 } 1717 1718 #ifdef CONFIG_BPF_SYSCALL 1719 static int bpf_fd_pass(const struct file *file, u32 sid); 1720 #endif 1721 1722 /* Check whether a task can use an open file descriptor to 1723 access an inode in a given way. Check access to the 1724 descriptor itself, and then use dentry_has_perm to 1725 check a particular permission to the file. 1726 Access to the descriptor is implicitly granted if it 1727 has the same SID as the process. If av is zero, then 1728 access to the file is not checked, e.g. for cases 1729 where only the descriptor is affected like seek. */ 1730 static int file_has_perm(const struct cred *cred, 1731 struct file *file, 1732 u32 av) 1733 { 1734 struct file_security_struct *fsec = selinux_file(file); 1735 struct inode *inode = file_inode(file); 1736 struct common_audit_data ad; 1737 u32 sid = cred_sid(cred); 1738 int rc; 1739 1740 ad.type = LSM_AUDIT_DATA_FILE; 1741 ad.u.file = file; 1742 1743 if (sid != fsec->sid) { 1744 rc = avc_has_perm(sid, fsec->sid, 1745 SECCLASS_FD, 1746 FD__USE, 1747 &ad); 1748 if (rc) 1749 goto out; 1750 } 1751 1752 #ifdef CONFIG_BPF_SYSCALL 1753 rc = bpf_fd_pass(file, cred_sid(cred)); 1754 if (rc) 1755 return rc; 1756 #endif 1757 1758 /* av is zero if only checking access to the descriptor. */ 1759 rc = 0; 1760 if (av) 1761 rc = inode_has_perm(cred, inode, av, &ad); 1762 1763 out: 1764 return rc; 1765 } 1766 1767 /* 1768 * Determine the label for an inode that might be unioned. 1769 */ 1770 static int 1771 selinux_determine_inode_label(const struct task_security_struct *tsec, 1772 struct inode *dir, 1773 const struct qstr *name, u16 tclass, 1774 u32 *_new_isid) 1775 { 1776 const struct superblock_security_struct *sbsec = 1777 selinux_superblock(dir->i_sb); 1778 1779 if ((sbsec->flags & SE_SBINITIALIZED) && 1780 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1781 *_new_isid = sbsec->mntpoint_sid; 1782 } else if ((sbsec->flags & SBLABEL_MNT) && 1783 tsec->create_sid) { 1784 *_new_isid = tsec->create_sid; 1785 } else { 1786 const struct inode_security_struct *dsec = inode_security(dir); 1787 return security_transition_sid(tsec->sid, 1788 dsec->sid, tclass, 1789 name, _new_isid); 1790 } 1791 1792 return 0; 1793 } 1794 1795 /* Check whether a task can create a file. */ 1796 static int may_create(struct inode *dir, 1797 struct dentry *dentry, 1798 u16 tclass) 1799 { 1800 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1801 struct inode_security_struct *dsec; 1802 struct superblock_security_struct *sbsec; 1803 u32 sid, newsid; 1804 struct common_audit_data ad; 1805 int rc; 1806 1807 dsec = inode_security(dir); 1808 sbsec = selinux_superblock(dir->i_sb); 1809 1810 sid = tsec->sid; 1811 1812 ad.type = LSM_AUDIT_DATA_DENTRY; 1813 ad.u.dentry = dentry; 1814 1815 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1816 DIR__ADD_NAME | DIR__SEARCH, 1817 &ad); 1818 if (rc) 1819 return rc; 1820 1821 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1822 &newsid); 1823 if (rc) 1824 return rc; 1825 1826 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1827 if (rc) 1828 return rc; 1829 1830 return avc_has_perm(newsid, sbsec->sid, 1831 SECCLASS_FILESYSTEM, 1832 FILESYSTEM__ASSOCIATE, &ad); 1833 } 1834 1835 #define MAY_LINK 0 1836 #define MAY_UNLINK 1 1837 #define MAY_RMDIR 2 1838 1839 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1840 static int may_link(struct inode *dir, 1841 struct dentry *dentry, 1842 int kind) 1843 1844 { 1845 struct inode_security_struct *dsec, *isec; 1846 struct common_audit_data ad; 1847 u32 sid = current_sid(); 1848 u32 av; 1849 int rc; 1850 1851 dsec = inode_security(dir); 1852 isec = backing_inode_security(dentry); 1853 1854 ad.type = LSM_AUDIT_DATA_DENTRY; 1855 ad.u.dentry = dentry; 1856 1857 av = DIR__SEARCH; 1858 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1859 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1860 if (rc) 1861 return rc; 1862 1863 switch (kind) { 1864 case MAY_LINK: 1865 av = FILE__LINK; 1866 break; 1867 case MAY_UNLINK: 1868 av = FILE__UNLINK; 1869 break; 1870 case MAY_RMDIR: 1871 av = DIR__RMDIR; 1872 break; 1873 default: 1874 pr_warn("SELinux: %s: unrecognized kind %d\n", 1875 __func__, kind); 1876 return 0; 1877 } 1878 1879 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1880 return rc; 1881 } 1882 1883 static inline int may_rename(struct inode *old_dir, 1884 struct dentry *old_dentry, 1885 struct inode *new_dir, 1886 struct dentry *new_dentry) 1887 { 1888 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1889 struct common_audit_data ad; 1890 u32 sid = current_sid(); 1891 u32 av; 1892 int old_is_dir, new_is_dir; 1893 int rc; 1894 1895 old_dsec = inode_security(old_dir); 1896 old_isec = backing_inode_security(old_dentry); 1897 old_is_dir = d_is_dir(old_dentry); 1898 new_dsec = inode_security(new_dir); 1899 1900 ad.type = LSM_AUDIT_DATA_DENTRY; 1901 1902 ad.u.dentry = old_dentry; 1903 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1904 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1905 if (rc) 1906 return rc; 1907 rc = avc_has_perm(sid, old_isec->sid, 1908 old_isec->sclass, FILE__RENAME, &ad); 1909 if (rc) 1910 return rc; 1911 if (old_is_dir && new_dir != old_dir) { 1912 rc = avc_has_perm(sid, old_isec->sid, 1913 old_isec->sclass, DIR__REPARENT, &ad); 1914 if (rc) 1915 return rc; 1916 } 1917 1918 ad.u.dentry = new_dentry; 1919 av = DIR__ADD_NAME | DIR__SEARCH; 1920 if (d_is_positive(new_dentry)) 1921 av |= DIR__REMOVE_NAME; 1922 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1923 if (rc) 1924 return rc; 1925 if (d_is_positive(new_dentry)) { 1926 new_isec = backing_inode_security(new_dentry); 1927 new_is_dir = d_is_dir(new_dentry); 1928 rc = avc_has_perm(sid, new_isec->sid, 1929 new_isec->sclass, 1930 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1931 if (rc) 1932 return rc; 1933 } 1934 1935 return 0; 1936 } 1937 1938 /* Check whether a task can perform a filesystem operation. */ 1939 static int superblock_has_perm(const struct cred *cred, 1940 const struct super_block *sb, 1941 u32 perms, 1942 struct common_audit_data *ad) 1943 { 1944 struct superblock_security_struct *sbsec; 1945 u32 sid = cred_sid(cred); 1946 1947 sbsec = selinux_superblock(sb); 1948 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1949 } 1950 1951 /* Convert a Linux mode and permission mask to an access vector. */ 1952 static inline u32 file_mask_to_av(int mode, int mask) 1953 { 1954 u32 av = 0; 1955 1956 if (!S_ISDIR(mode)) { 1957 if (mask & MAY_EXEC) 1958 av |= FILE__EXECUTE; 1959 if (mask & MAY_READ) 1960 av |= FILE__READ; 1961 1962 if (mask & MAY_APPEND) 1963 av |= FILE__APPEND; 1964 else if (mask & MAY_WRITE) 1965 av |= FILE__WRITE; 1966 1967 } else { 1968 if (mask & MAY_EXEC) 1969 av |= DIR__SEARCH; 1970 if (mask & MAY_WRITE) 1971 av |= DIR__WRITE; 1972 if (mask & MAY_READ) 1973 av |= DIR__READ; 1974 } 1975 1976 return av; 1977 } 1978 1979 /* Convert a Linux file to an access vector. */ 1980 static inline u32 file_to_av(const struct file *file) 1981 { 1982 u32 av = 0; 1983 1984 if (file->f_mode & FMODE_READ) 1985 av |= FILE__READ; 1986 if (file->f_mode & FMODE_WRITE) { 1987 if (file->f_flags & O_APPEND) 1988 av |= FILE__APPEND; 1989 else 1990 av |= FILE__WRITE; 1991 } 1992 if (!av) { 1993 /* 1994 * Special file opened with flags 3 for ioctl-only use. 1995 */ 1996 av = FILE__IOCTL; 1997 } 1998 1999 return av; 2000 } 2001 2002 /* 2003 * Convert a file to an access vector and include the correct 2004 * open permission. 2005 */ 2006 static inline u32 open_file_to_av(struct file *file) 2007 { 2008 u32 av = file_to_av(file); 2009 struct inode *inode = file_inode(file); 2010 2011 if (selinux_policycap_openperm() && 2012 inode->i_sb->s_magic != SOCKFS_MAGIC) 2013 av |= FILE__OPEN; 2014 2015 return av; 2016 } 2017 2018 /* Hook functions begin here. */ 2019 2020 static int selinux_binder_set_context_mgr(const struct cred *mgr) 2021 { 2022 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, 2023 BINDER__SET_CONTEXT_MGR, NULL); 2024 } 2025 2026 static int selinux_binder_transaction(const struct cred *from, 2027 const struct cred *to) 2028 { 2029 u32 mysid = current_sid(); 2030 u32 fromsid = cred_sid(from); 2031 u32 tosid = cred_sid(to); 2032 int rc; 2033 2034 if (mysid != fromsid) { 2035 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2036 BINDER__IMPERSONATE, NULL); 2037 if (rc) 2038 return rc; 2039 } 2040 2041 return avc_has_perm(fromsid, tosid, 2042 SECCLASS_BINDER, BINDER__CALL, NULL); 2043 } 2044 2045 static int selinux_binder_transfer_binder(const struct cred *from, 2046 const struct cred *to) 2047 { 2048 return avc_has_perm(cred_sid(from), cred_sid(to), 2049 SECCLASS_BINDER, BINDER__TRANSFER, 2050 NULL); 2051 } 2052 2053 static int selinux_binder_transfer_file(const struct cred *from, 2054 const struct cred *to, 2055 const struct file *file) 2056 { 2057 u32 sid = cred_sid(to); 2058 struct file_security_struct *fsec = selinux_file(file); 2059 struct dentry *dentry = file->f_path.dentry; 2060 struct inode_security_struct *isec; 2061 struct common_audit_data ad; 2062 int rc; 2063 2064 ad.type = LSM_AUDIT_DATA_PATH; 2065 ad.u.path = file->f_path; 2066 2067 if (sid != fsec->sid) { 2068 rc = avc_has_perm(sid, fsec->sid, 2069 SECCLASS_FD, 2070 FD__USE, 2071 &ad); 2072 if (rc) 2073 return rc; 2074 } 2075 2076 #ifdef CONFIG_BPF_SYSCALL 2077 rc = bpf_fd_pass(file, sid); 2078 if (rc) 2079 return rc; 2080 #endif 2081 2082 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2083 return 0; 2084 2085 isec = backing_inode_security(dentry); 2086 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2087 &ad); 2088 } 2089 2090 static int selinux_ptrace_access_check(struct task_struct *child, 2091 unsigned int mode) 2092 { 2093 u32 sid = current_sid(); 2094 u32 csid = task_sid_obj(child); 2095 2096 if (mode & PTRACE_MODE_READ) 2097 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, 2098 NULL); 2099 2100 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, 2101 NULL); 2102 } 2103 2104 static int selinux_ptrace_traceme(struct task_struct *parent) 2105 { 2106 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), 2107 SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2108 } 2109 2110 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, 2111 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2112 { 2113 return avc_has_perm(current_sid(), task_sid_obj(target), 2114 SECCLASS_PROCESS, PROCESS__GETCAP, NULL); 2115 } 2116 2117 static int selinux_capset(struct cred *new, const struct cred *old, 2118 const kernel_cap_t *effective, 2119 const kernel_cap_t *inheritable, 2120 const kernel_cap_t *permitted) 2121 { 2122 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2123 PROCESS__SETCAP, NULL); 2124 } 2125 2126 /* 2127 * (This comment used to live with the selinux_task_setuid hook, 2128 * which was removed). 2129 * 2130 * Since setuid only affects the current process, and since the SELinux 2131 * controls are not based on the Linux identity attributes, SELinux does not 2132 * need to control this operation. However, SELinux does control the use of 2133 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2134 */ 2135 2136 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2137 int cap, unsigned int opts) 2138 { 2139 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2140 } 2141 2142 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb) 2143 { 2144 const struct cred *cred = current_cred(); 2145 int rc = 0; 2146 2147 if (!sb) 2148 return 0; 2149 2150 switch (cmds) { 2151 case Q_SYNC: 2152 case Q_QUOTAON: 2153 case Q_QUOTAOFF: 2154 case Q_SETINFO: 2155 case Q_SETQUOTA: 2156 case Q_XQUOTAOFF: 2157 case Q_XQUOTAON: 2158 case Q_XSETQLIM: 2159 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2160 break; 2161 case Q_GETFMT: 2162 case Q_GETINFO: 2163 case Q_GETQUOTA: 2164 case Q_XGETQUOTA: 2165 case Q_XGETQSTAT: 2166 case Q_XGETQSTATV: 2167 case Q_XGETNEXTQUOTA: 2168 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2169 break; 2170 default: 2171 rc = 0; /* let the kernel handle invalid cmds */ 2172 break; 2173 } 2174 return rc; 2175 } 2176 2177 static int selinux_quota_on(struct dentry *dentry) 2178 { 2179 const struct cred *cred = current_cred(); 2180 2181 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2182 } 2183 2184 static int selinux_syslog(int type) 2185 { 2186 switch (type) { 2187 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2188 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2189 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2190 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2191 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2192 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2193 /* Set level of messages printed to console */ 2194 case SYSLOG_ACTION_CONSOLE_LEVEL: 2195 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2196 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2197 NULL); 2198 } 2199 /* All other syslog types */ 2200 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2201 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2202 } 2203 2204 /* 2205 * Check that a process has enough memory to allocate a new virtual 2206 * mapping. 0 means there is enough memory for the allocation to 2207 * succeed and -ENOMEM implies there is not. 2208 * 2209 * Do not audit the selinux permission check, as this is applied to all 2210 * processes that allocate mappings. 2211 */ 2212 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2213 { 2214 int rc, cap_sys_admin = 0; 2215 2216 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2217 CAP_OPT_NOAUDIT, true); 2218 if (rc == 0) 2219 cap_sys_admin = 1; 2220 2221 return cap_sys_admin; 2222 } 2223 2224 /* binprm security operations */ 2225 2226 static u32 ptrace_parent_sid(void) 2227 { 2228 u32 sid = 0; 2229 struct task_struct *tracer; 2230 2231 rcu_read_lock(); 2232 tracer = ptrace_parent(current); 2233 if (tracer) 2234 sid = task_sid_obj(tracer); 2235 rcu_read_unlock(); 2236 2237 return sid; 2238 } 2239 2240 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2241 const struct task_security_struct *old_tsec, 2242 const struct task_security_struct *new_tsec) 2243 { 2244 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2245 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2246 int rc; 2247 u32 av; 2248 2249 if (!nnp && !nosuid) 2250 return 0; /* neither NNP nor nosuid */ 2251 2252 if (new_tsec->sid == old_tsec->sid) 2253 return 0; /* No change in credentials */ 2254 2255 /* 2256 * If the policy enables the nnp_nosuid_transition policy capability, 2257 * then we permit transitions under NNP or nosuid if the 2258 * policy allows the corresponding permission between 2259 * the old and new contexts. 2260 */ 2261 if (selinux_policycap_nnp_nosuid_transition()) { 2262 av = 0; 2263 if (nnp) 2264 av |= PROCESS2__NNP_TRANSITION; 2265 if (nosuid) 2266 av |= PROCESS2__NOSUID_TRANSITION; 2267 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2268 SECCLASS_PROCESS2, av, NULL); 2269 if (!rc) 2270 return 0; 2271 } 2272 2273 /* 2274 * We also permit NNP or nosuid transitions to bounded SIDs, 2275 * i.e. SIDs that are guaranteed to only be allowed a subset 2276 * of the permissions of the current SID. 2277 */ 2278 rc = security_bounded_transition(old_tsec->sid, 2279 new_tsec->sid); 2280 if (!rc) 2281 return 0; 2282 2283 /* 2284 * On failure, preserve the errno values for NNP vs nosuid. 2285 * NNP: Operation not permitted for caller. 2286 * nosuid: Permission denied to file. 2287 */ 2288 if (nnp) 2289 return -EPERM; 2290 return -EACCES; 2291 } 2292 2293 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2294 { 2295 const struct task_security_struct *old_tsec; 2296 struct task_security_struct *new_tsec; 2297 struct inode_security_struct *isec; 2298 struct common_audit_data ad; 2299 struct inode *inode = file_inode(bprm->file); 2300 int rc; 2301 2302 /* SELinux context only depends on initial program or script and not 2303 * the script interpreter */ 2304 2305 old_tsec = selinux_cred(current_cred()); 2306 new_tsec = selinux_cred(bprm->cred); 2307 isec = inode_security(inode); 2308 2309 /* Default to the current task SID. */ 2310 new_tsec->sid = old_tsec->sid; 2311 new_tsec->osid = old_tsec->sid; 2312 2313 /* Reset fs, key, and sock SIDs on execve. */ 2314 new_tsec->create_sid = 0; 2315 new_tsec->keycreate_sid = 0; 2316 new_tsec->sockcreate_sid = 0; 2317 2318 /* 2319 * Before policy is loaded, label any task outside kernel space 2320 * as SECINITSID_INIT, so that any userspace tasks surviving from 2321 * early boot end up with a label different from SECINITSID_KERNEL 2322 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL). 2323 */ 2324 if (!selinux_initialized()) { 2325 new_tsec->sid = SECINITSID_INIT; 2326 /* also clear the exec_sid just in case */ 2327 new_tsec->exec_sid = 0; 2328 return 0; 2329 } 2330 2331 if (old_tsec->exec_sid) { 2332 new_tsec->sid = old_tsec->exec_sid; 2333 /* Reset exec SID on execve. */ 2334 new_tsec->exec_sid = 0; 2335 2336 /* Fail on NNP or nosuid if not an allowed transition. */ 2337 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2338 if (rc) 2339 return rc; 2340 } else { 2341 /* Check for a default transition on this program. */ 2342 rc = security_transition_sid(old_tsec->sid, 2343 isec->sid, SECCLASS_PROCESS, NULL, 2344 &new_tsec->sid); 2345 if (rc) 2346 return rc; 2347 2348 /* 2349 * Fallback to old SID on NNP or nosuid if not an allowed 2350 * transition. 2351 */ 2352 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2353 if (rc) 2354 new_tsec->sid = old_tsec->sid; 2355 } 2356 2357 ad.type = LSM_AUDIT_DATA_FILE; 2358 ad.u.file = bprm->file; 2359 2360 if (new_tsec->sid == old_tsec->sid) { 2361 rc = avc_has_perm(old_tsec->sid, isec->sid, 2362 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2363 if (rc) 2364 return rc; 2365 } else { 2366 /* Check permissions for the transition. */ 2367 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2368 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2369 if (rc) 2370 return rc; 2371 2372 rc = avc_has_perm(new_tsec->sid, isec->sid, 2373 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2374 if (rc) 2375 return rc; 2376 2377 /* Check for shared state */ 2378 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2379 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2380 SECCLASS_PROCESS, PROCESS__SHARE, 2381 NULL); 2382 if (rc) 2383 return -EPERM; 2384 } 2385 2386 /* Make sure that anyone attempting to ptrace over a task that 2387 * changes its SID has the appropriate permit */ 2388 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2389 u32 ptsid = ptrace_parent_sid(); 2390 if (ptsid != 0) { 2391 rc = avc_has_perm(ptsid, new_tsec->sid, 2392 SECCLASS_PROCESS, 2393 PROCESS__PTRACE, NULL); 2394 if (rc) 2395 return -EPERM; 2396 } 2397 } 2398 2399 /* Clear any possibly unsafe personality bits on exec: */ 2400 bprm->per_clear |= PER_CLEAR_ON_SETID; 2401 2402 /* Enable secure mode for SIDs transitions unless 2403 the noatsecure permission is granted between 2404 the two SIDs, i.e. ahp returns 0. */ 2405 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2406 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2407 NULL); 2408 bprm->secureexec |= !!rc; 2409 } 2410 2411 return 0; 2412 } 2413 2414 static int match_file(const void *p, struct file *file, unsigned fd) 2415 { 2416 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2417 } 2418 2419 /* Derived from fs/exec.c:flush_old_files. */ 2420 static inline void flush_unauthorized_files(const struct cred *cred, 2421 struct files_struct *files) 2422 { 2423 struct file *file, *devnull = NULL; 2424 struct tty_struct *tty; 2425 int drop_tty = 0; 2426 unsigned n; 2427 2428 tty = get_current_tty(); 2429 if (tty) { 2430 spin_lock(&tty->files_lock); 2431 if (!list_empty(&tty->tty_files)) { 2432 struct tty_file_private *file_priv; 2433 2434 /* Revalidate access to controlling tty. 2435 Use file_path_has_perm on the tty path directly 2436 rather than using file_has_perm, as this particular 2437 open file may belong to another process and we are 2438 only interested in the inode-based check here. */ 2439 file_priv = list_first_entry(&tty->tty_files, 2440 struct tty_file_private, list); 2441 file = file_priv->file; 2442 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2443 drop_tty = 1; 2444 } 2445 spin_unlock(&tty->files_lock); 2446 tty_kref_put(tty); 2447 } 2448 /* Reset controlling tty. */ 2449 if (drop_tty) 2450 no_tty(); 2451 2452 /* Revalidate access to inherited open files. */ 2453 n = iterate_fd(files, 0, match_file, cred); 2454 if (!n) /* none found? */ 2455 return; 2456 2457 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2458 if (IS_ERR(devnull)) 2459 devnull = NULL; 2460 /* replace all the matching ones with this */ 2461 do { 2462 replace_fd(n - 1, devnull, 0); 2463 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2464 if (devnull) 2465 fput(devnull); 2466 } 2467 2468 /* 2469 * Prepare a process for imminent new credential changes due to exec 2470 */ 2471 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) 2472 { 2473 struct task_security_struct *new_tsec; 2474 struct rlimit *rlim, *initrlim; 2475 int rc, i; 2476 2477 new_tsec = selinux_cred(bprm->cred); 2478 if (new_tsec->sid == new_tsec->osid) 2479 return; 2480 2481 /* Close files for which the new task SID is not authorized. */ 2482 flush_unauthorized_files(bprm->cred, current->files); 2483 2484 /* Always clear parent death signal on SID transitions. */ 2485 current->pdeath_signal = 0; 2486 2487 /* Check whether the new SID can inherit resource limits from the old 2488 * SID. If not, reset all soft limits to the lower of the current 2489 * task's hard limit and the init task's soft limit. 2490 * 2491 * Note that the setting of hard limits (even to lower them) can be 2492 * controlled by the setrlimit check. The inclusion of the init task's 2493 * soft limit into the computation is to avoid resetting soft limits 2494 * higher than the default soft limit for cases where the default is 2495 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2496 */ 2497 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2498 PROCESS__RLIMITINH, NULL); 2499 if (rc) { 2500 /* protect against do_prlimit() */ 2501 task_lock(current); 2502 for (i = 0; i < RLIM_NLIMITS; i++) { 2503 rlim = current->signal->rlim + i; 2504 initrlim = init_task.signal->rlim + i; 2505 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2506 } 2507 task_unlock(current); 2508 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2509 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2510 } 2511 } 2512 2513 /* 2514 * Clean up the process immediately after the installation of new credentials 2515 * due to exec 2516 */ 2517 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) 2518 { 2519 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2520 u32 osid, sid; 2521 int rc; 2522 2523 osid = tsec->osid; 2524 sid = tsec->sid; 2525 2526 if (sid == osid) 2527 return; 2528 2529 /* Check whether the new SID can inherit signal state from the old SID. 2530 * If not, clear itimers to avoid subsequent signal generation and 2531 * flush and unblock signals. 2532 * 2533 * This must occur _after_ the task SID has been updated so that any 2534 * kill done after the flush will be checked against the new SID. 2535 */ 2536 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2537 if (rc) { 2538 clear_itimer(); 2539 2540 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); 2541 if (!fatal_signal_pending(current)) { 2542 flush_sigqueue(¤t->pending); 2543 flush_sigqueue(¤t->signal->shared_pending); 2544 flush_signal_handlers(current, 1); 2545 sigemptyset(¤t->blocked); 2546 recalc_sigpending(); 2547 } 2548 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); 2549 } 2550 2551 /* Wake up the parent if it is waiting so that it can recheck 2552 * wait permission to the new task SID. */ 2553 read_lock(&tasklist_lock); 2554 __wake_up_parent(current, unrcu_pointer(current->real_parent)); 2555 read_unlock(&tasklist_lock); 2556 } 2557 2558 /* superblock security operations */ 2559 2560 static int selinux_sb_alloc_security(struct super_block *sb) 2561 { 2562 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2563 2564 mutex_init(&sbsec->lock); 2565 INIT_LIST_HEAD(&sbsec->isec_head); 2566 spin_lock_init(&sbsec->isec_lock); 2567 sbsec->sid = SECINITSID_UNLABELED; 2568 sbsec->def_sid = SECINITSID_FILE; 2569 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2570 2571 return 0; 2572 } 2573 2574 static inline int opt_len(const char *s) 2575 { 2576 bool open_quote = false; 2577 int len; 2578 char c; 2579 2580 for (len = 0; (c = s[len]) != '\0'; len++) { 2581 if (c == '"') 2582 open_quote = !open_quote; 2583 if (c == ',' && !open_quote) 2584 break; 2585 } 2586 return len; 2587 } 2588 2589 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2590 { 2591 char *from = options; 2592 char *to = options; 2593 bool first = true; 2594 int rc; 2595 2596 while (1) { 2597 int len = opt_len(from); 2598 int token; 2599 char *arg = NULL; 2600 2601 token = match_opt_prefix(from, len, &arg); 2602 2603 if (token != Opt_error) { 2604 char *p, *q; 2605 2606 /* strip quotes */ 2607 if (arg) { 2608 for (p = q = arg; p < from + len; p++) { 2609 char c = *p; 2610 if (c != '"') 2611 *q++ = c; 2612 } 2613 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2614 if (!arg) { 2615 rc = -ENOMEM; 2616 goto free_opt; 2617 } 2618 } 2619 rc = selinux_add_opt(token, arg, mnt_opts); 2620 kfree(arg); 2621 arg = NULL; 2622 if (unlikely(rc)) { 2623 goto free_opt; 2624 } 2625 } else { 2626 if (!first) { // copy with preceding comma 2627 from--; 2628 len++; 2629 } 2630 if (to != from) 2631 memmove(to, from, len); 2632 to += len; 2633 first = false; 2634 } 2635 if (!from[len]) 2636 break; 2637 from += len + 1; 2638 } 2639 *to = '\0'; 2640 return 0; 2641 2642 free_opt: 2643 if (*mnt_opts) { 2644 selinux_free_mnt_opts(*mnt_opts); 2645 *mnt_opts = NULL; 2646 } 2647 return rc; 2648 } 2649 2650 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2651 { 2652 struct selinux_mnt_opts *opts = mnt_opts; 2653 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2654 2655 /* 2656 * Superblock not initialized (i.e. no options) - reject if any 2657 * options specified, otherwise accept. 2658 */ 2659 if (!(sbsec->flags & SE_SBINITIALIZED)) 2660 return opts ? 1 : 0; 2661 2662 /* 2663 * Superblock initialized and no options specified - reject if 2664 * superblock has any options set, otherwise accept. 2665 */ 2666 if (!opts) 2667 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2668 2669 if (opts->fscontext_sid) { 2670 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2671 opts->fscontext_sid)) 2672 return 1; 2673 } 2674 if (opts->context_sid) { 2675 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2676 opts->context_sid)) 2677 return 1; 2678 } 2679 if (opts->rootcontext_sid) { 2680 struct inode_security_struct *root_isec; 2681 2682 root_isec = backing_inode_security(sb->s_root); 2683 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2684 opts->rootcontext_sid)) 2685 return 1; 2686 } 2687 if (opts->defcontext_sid) { 2688 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2689 opts->defcontext_sid)) 2690 return 1; 2691 } 2692 return 0; 2693 } 2694 2695 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2696 { 2697 struct selinux_mnt_opts *opts = mnt_opts; 2698 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2699 2700 if (!(sbsec->flags & SE_SBINITIALIZED)) 2701 return 0; 2702 2703 if (!opts) 2704 return 0; 2705 2706 if (opts->fscontext_sid) { 2707 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2708 opts->fscontext_sid)) 2709 goto out_bad_option; 2710 } 2711 if (opts->context_sid) { 2712 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2713 opts->context_sid)) 2714 goto out_bad_option; 2715 } 2716 if (opts->rootcontext_sid) { 2717 struct inode_security_struct *root_isec; 2718 root_isec = backing_inode_security(sb->s_root); 2719 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2720 opts->rootcontext_sid)) 2721 goto out_bad_option; 2722 } 2723 if (opts->defcontext_sid) { 2724 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2725 opts->defcontext_sid)) 2726 goto out_bad_option; 2727 } 2728 return 0; 2729 2730 out_bad_option: 2731 pr_warn("SELinux: unable to change security options " 2732 "during remount (dev %s, type=%s)\n", sb->s_id, 2733 sb->s_type->name); 2734 return -EINVAL; 2735 } 2736 2737 static int selinux_sb_kern_mount(const struct super_block *sb) 2738 { 2739 const struct cred *cred = current_cred(); 2740 struct common_audit_data ad; 2741 2742 ad.type = LSM_AUDIT_DATA_DENTRY; 2743 ad.u.dentry = sb->s_root; 2744 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2745 } 2746 2747 static int selinux_sb_statfs(struct dentry *dentry) 2748 { 2749 const struct cred *cred = current_cred(); 2750 struct common_audit_data ad; 2751 2752 ad.type = LSM_AUDIT_DATA_DENTRY; 2753 ad.u.dentry = dentry->d_sb->s_root; 2754 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2755 } 2756 2757 static int selinux_mount(const char *dev_name, 2758 const struct path *path, 2759 const char *type, 2760 unsigned long flags, 2761 void *data) 2762 { 2763 const struct cred *cred = current_cred(); 2764 2765 if (flags & MS_REMOUNT) 2766 return superblock_has_perm(cred, path->dentry->d_sb, 2767 FILESYSTEM__REMOUNT, NULL); 2768 else 2769 return path_has_perm(cred, path, FILE__MOUNTON); 2770 } 2771 2772 static int selinux_move_mount(const struct path *from_path, 2773 const struct path *to_path) 2774 { 2775 const struct cred *cred = current_cred(); 2776 2777 return path_has_perm(cred, to_path, FILE__MOUNTON); 2778 } 2779 2780 static int selinux_umount(struct vfsmount *mnt, int flags) 2781 { 2782 const struct cred *cred = current_cred(); 2783 2784 return superblock_has_perm(cred, mnt->mnt_sb, 2785 FILESYSTEM__UNMOUNT, NULL); 2786 } 2787 2788 static int selinux_fs_context_submount(struct fs_context *fc, 2789 struct super_block *reference) 2790 { 2791 const struct superblock_security_struct *sbsec = selinux_superblock(reference); 2792 struct selinux_mnt_opts *opts; 2793 2794 /* 2795 * Ensure that fc->security remains NULL when no options are set 2796 * as expected by selinux_set_mnt_opts(). 2797 */ 2798 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) 2799 return 0; 2800 2801 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 2802 if (!opts) 2803 return -ENOMEM; 2804 2805 if (sbsec->flags & FSCONTEXT_MNT) 2806 opts->fscontext_sid = sbsec->sid; 2807 if (sbsec->flags & CONTEXT_MNT) 2808 opts->context_sid = sbsec->mntpoint_sid; 2809 if (sbsec->flags & DEFCONTEXT_MNT) 2810 opts->defcontext_sid = sbsec->def_sid; 2811 fc->security = opts; 2812 return 0; 2813 } 2814 2815 static int selinux_fs_context_dup(struct fs_context *fc, 2816 struct fs_context *src_fc) 2817 { 2818 const struct selinux_mnt_opts *src = src_fc->security; 2819 2820 if (!src) 2821 return 0; 2822 2823 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); 2824 return fc->security ? 0 : -ENOMEM; 2825 } 2826 2827 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2828 fsparam_string(CONTEXT_STR, Opt_context), 2829 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2830 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2831 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2832 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2833 {} 2834 }; 2835 2836 static int selinux_fs_context_parse_param(struct fs_context *fc, 2837 struct fs_parameter *param) 2838 { 2839 struct fs_parse_result result; 2840 int opt; 2841 2842 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2843 if (opt < 0) 2844 return opt; 2845 2846 return selinux_add_opt(opt, param->string, &fc->security); 2847 } 2848 2849 /* inode security operations */ 2850 2851 static int selinux_inode_alloc_security(struct inode *inode) 2852 { 2853 struct inode_security_struct *isec = selinux_inode(inode); 2854 u32 sid = current_sid(); 2855 2856 spin_lock_init(&isec->lock); 2857 INIT_LIST_HEAD(&isec->list); 2858 isec->inode = inode; 2859 isec->sid = SECINITSID_UNLABELED; 2860 isec->sclass = SECCLASS_FILE; 2861 isec->task_sid = sid; 2862 isec->initialized = LABEL_INVALID; 2863 2864 return 0; 2865 } 2866 2867 static void selinux_inode_free_security(struct inode *inode) 2868 { 2869 inode_free_security(inode); 2870 } 2871 2872 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2873 const struct qstr *name, 2874 const char **xattr_name, void **ctx, 2875 u32 *ctxlen) 2876 { 2877 u32 newsid; 2878 int rc; 2879 2880 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2881 d_inode(dentry->d_parent), name, 2882 inode_mode_to_security_class(mode), 2883 &newsid); 2884 if (rc) 2885 return rc; 2886 2887 if (xattr_name) 2888 *xattr_name = XATTR_NAME_SELINUX; 2889 2890 return security_sid_to_context(newsid, (char **)ctx, 2891 ctxlen); 2892 } 2893 2894 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2895 struct qstr *name, 2896 const struct cred *old, 2897 struct cred *new) 2898 { 2899 u32 newsid; 2900 int rc; 2901 struct task_security_struct *tsec; 2902 2903 rc = selinux_determine_inode_label(selinux_cred(old), 2904 d_inode(dentry->d_parent), name, 2905 inode_mode_to_security_class(mode), 2906 &newsid); 2907 if (rc) 2908 return rc; 2909 2910 tsec = selinux_cred(new); 2911 tsec->create_sid = newsid; 2912 return 0; 2913 } 2914 2915 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2916 const struct qstr *qstr, 2917 struct xattr *xattrs, int *xattr_count) 2918 { 2919 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2920 struct superblock_security_struct *sbsec; 2921 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); 2922 u32 newsid, clen; 2923 int rc; 2924 char *context; 2925 2926 sbsec = selinux_superblock(dir->i_sb); 2927 2928 newsid = tsec->create_sid; 2929 2930 rc = selinux_determine_inode_label(tsec, dir, qstr, 2931 inode_mode_to_security_class(inode->i_mode), 2932 &newsid); 2933 if (rc) 2934 return rc; 2935 2936 /* Possibly defer initialization to selinux_complete_init. */ 2937 if (sbsec->flags & SE_SBINITIALIZED) { 2938 struct inode_security_struct *isec = selinux_inode(inode); 2939 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2940 isec->sid = newsid; 2941 isec->initialized = LABEL_INITIALIZED; 2942 } 2943 2944 if (!selinux_initialized() || 2945 !(sbsec->flags & SBLABEL_MNT)) 2946 return -EOPNOTSUPP; 2947 2948 if (xattr) { 2949 rc = security_sid_to_context_force(newsid, 2950 &context, &clen); 2951 if (rc) 2952 return rc; 2953 xattr->value = context; 2954 xattr->value_len = clen; 2955 xattr->name = XATTR_SELINUX_SUFFIX; 2956 } 2957 2958 return 0; 2959 } 2960 2961 static int selinux_inode_init_security_anon(struct inode *inode, 2962 const struct qstr *name, 2963 const struct inode *context_inode) 2964 { 2965 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2966 struct common_audit_data ad; 2967 struct inode_security_struct *isec; 2968 int rc; 2969 2970 if (unlikely(!selinux_initialized())) 2971 return 0; 2972 2973 isec = selinux_inode(inode); 2974 2975 /* 2976 * We only get here once per ephemeral inode. The inode has 2977 * been initialized via inode_alloc_security but is otherwise 2978 * untouched. 2979 */ 2980 2981 if (context_inode) { 2982 struct inode_security_struct *context_isec = 2983 selinux_inode(context_inode); 2984 if (context_isec->initialized != LABEL_INITIALIZED) { 2985 pr_err("SELinux: context_inode is not initialized\n"); 2986 return -EACCES; 2987 } 2988 2989 isec->sclass = context_isec->sclass; 2990 isec->sid = context_isec->sid; 2991 } else { 2992 isec->sclass = SECCLASS_ANON_INODE; 2993 rc = security_transition_sid( 2994 tsec->sid, tsec->sid, 2995 isec->sclass, name, &isec->sid); 2996 if (rc) 2997 return rc; 2998 } 2999 3000 isec->initialized = LABEL_INITIALIZED; 3001 /* 3002 * Now that we've initialized security, check whether we're 3003 * allowed to actually create this type of anonymous inode. 3004 */ 3005 3006 ad.type = LSM_AUDIT_DATA_ANONINODE; 3007 ad.u.anonclass = name ? (const char *)name->name : "?"; 3008 3009 return avc_has_perm(tsec->sid, 3010 isec->sid, 3011 isec->sclass, 3012 FILE__CREATE, 3013 &ad); 3014 } 3015 3016 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3017 { 3018 return may_create(dir, dentry, SECCLASS_FILE); 3019 } 3020 3021 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3022 { 3023 return may_link(dir, old_dentry, MAY_LINK); 3024 } 3025 3026 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3027 { 3028 return may_link(dir, dentry, MAY_UNLINK); 3029 } 3030 3031 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3032 { 3033 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3034 } 3035 3036 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3037 { 3038 return may_create(dir, dentry, SECCLASS_DIR); 3039 } 3040 3041 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3042 { 3043 return may_link(dir, dentry, MAY_RMDIR); 3044 } 3045 3046 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3047 { 3048 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3049 } 3050 3051 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3052 struct inode *new_inode, struct dentry *new_dentry) 3053 { 3054 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3055 } 3056 3057 static int selinux_inode_readlink(struct dentry *dentry) 3058 { 3059 const struct cred *cred = current_cred(); 3060 3061 return dentry_has_perm(cred, dentry, FILE__READ); 3062 } 3063 3064 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3065 bool rcu) 3066 { 3067 const struct cred *cred = current_cred(); 3068 struct common_audit_data ad; 3069 struct inode_security_struct *isec; 3070 u32 sid; 3071 3072 validate_creds(cred); 3073 3074 ad.type = LSM_AUDIT_DATA_DENTRY; 3075 ad.u.dentry = dentry; 3076 sid = cred_sid(cred); 3077 isec = inode_security_rcu(inode, rcu); 3078 if (IS_ERR(isec)) 3079 return PTR_ERR(isec); 3080 3081 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); 3082 } 3083 3084 static noinline int audit_inode_permission(struct inode *inode, 3085 u32 perms, u32 audited, u32 denied, 3086 int result) 3087 { 3088 struct common_audit_data ad; 3089 struct inode_security_struct *isec = selinux_inode(inode); 3090 3091 ad.type = LSM_AUDIT_DATA_INODE; 3092 ad.u.inode = inode; 3093 3094 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3095 audited, denied, result, &ad); 3096 } 3097 3098 static int selinux_inode_permission(struct inode *inode, int mask) 3099 { 3100 const struct cred *cred = current_cred(); 3101 u32 perms; 3102 bool from_access; 3103 bool no_block = mask & MAY_NOT_BLOCK; 3104 struct inode_security_struct *isec; 3105 u32 sid; 3106 struct av_decision avd; 3107 int rc, rc2; 3108 u32 audited, denied; 3109 3110 from_access = mask & MAY_ACCESS; 3111 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3112 3113 /* No permission to check. Existence test. */ 3114 if (!mask) 3115 return 0; 3116 3117 validate_creds(cred); 3118 3119 if (unlikely(IS_PRIVATE(inode))) 3120 return 0; 3121 3122 perms = file_mask_to_av(inode->i_mode, mask); 3123 3124 sid = cred_sid(cred); 3125 isec = inode_security_rcu(inode, no_block); 3126 if (IS_ERR(isec)) 3127 return PTR_ERR(isec); 3128 3129 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, 3130 &avd); 3131 audited = avc_audit_required(perms, &avd, rc, 3132 from_access ? FILE__AUDIT_ACCESS : 0, 3133 &denied); 3134 if (likely(!audited)) 3135 return rc; 3136 3137 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3138 if (rc2) 3139 return rc2; 3140 return rc; 3141 } 3142 3143 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3144 { 3145 const struct cred *cred = current_cred(); 3146 struct inode *inode = d_backing_inode(dentry); 3147 unsigned int ia_valid = iattr->ia_valid; 3148 __u32 av = FILE__WRITE; 3149 3150 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3151 if (ia_valid & ATTR_FORCE) { 3152 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3153 ATTR_FORCE); 3154 if (!ia_valid) 3155 return 0; 3156 } 3157 3158 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3159 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3160 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3161 3162 if (selinux_policycap_openperm() && 3163 inode->i_sb->s_magic != SOCKFS_MAGIC && 3164 (ia_valid & ATTR_SIZE) && 3165 !(ia_valid & ATTR_FILE)) 3166 av |= FILE__OPEN; 3167 3168 return dentry_has_perm(cred, dentry, av); 3169 } 3170 3171 static int selinux_inode_getattr(const struct path *path) 3172 { 3173 return path_has_perm(current_cred(), path, FILE__GETATTR); 3174 } 3175 3176 static bool has_cap_mac_admin(bool audit) 3177 { 3178 const struct cred *cred = current_cred(); 3179 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3180 3181 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3182 return false; 3183 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3184 return false; 3185 return true; 3186 } 3187 3188 static int selinux_inode_setxattr(struct mnt_idmap *idmap, 3189 struct dentry *dentry, const char *name, 3190 const void *value, size_t size, int flags) 3191 { 3192 struct inode *inode = d_backing_inode(dentry); 3193 struct inode_security_struct *isec; 3194 struct superblock_security_struct *sbsec; 3195 struct common_audit_data ad; 3196 u32 newsid, sid = current_sid(); 3197 int rc = 0; 3198 3199 if (strcmp(name, XATTR_NAME_SELINUX)) { 3200 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3201 if (rc) 3202 return rc; 3203 3204 /* Not an attribute we recognize, so just check the 3205 ordinary setattr permission. */ 3206 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3207 } 3208 3209 if (!selinux_initialized()) 3210 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); 3211 3212 sbsec = selinux_superblock(inode->i_sb); 3213 if (!(sbsec->flags & SBLABEL_MNT)) 3214 return -EOPNOTSUPP; 3215 3216 if (!inode_owner_or_capable(idmap, inode)) 3217 return -EPERM; 3218 3219 ad.type = LSM_AUDIT_DATA_DENTRY; 3220 ad.u.dentry = dentry; 3221 3222 isec = backing_inode_security(dentry); 3223 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3224 FILE__RELABELFROM, &ad); 3225 if (rc) 3226 return rc; 3227 3228 rc = security_context_to_sid(value, size, &newsid, 3229 GFP_KERNEL); 3230 if (rc == -EINVAL) { 3231 if (!has_cap_mac_admin(true)) { 3232 struct audit_buffer *ab; 3233 size_t audit_size; 3234 3235 /* We strip a nul only if it is at the end, otherwise the 3236 * context contains a nul and we should audit that */ 3237 if (value) { 3238 const char *str = value; 3239 3240 if (str[size - 1] == '\0') 3241 audit_size = size - 1; 3242 else 3243 audit_size = size; 3244 } else { 3245 audit_size = 0; 3246 } 3247 ab = audit_log_start(audit_context(), 3248 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3249 if (!ab) 3250 return rc; 3251 audit_log_format(ab, "op=setxattr invalid_context="); 3252 audit_log_n_untrustedstring(ab, value, audit_size); 3253 audit_log_end(ab); 3254 3255 return rc; 3256 } 3257 rc = security_context_to_sid_force(value, 3258 size, &newsid); 3259 } 3260 if (rc) 3261 return rc; 3262 3263 rc = avc_has_perm(sid, newsid, isec->sclass, 3264 FILE__RELABELTO, &ad); 3265 if (rc) 3266 return rc; 3267 3268 rc = security_validate_transition(isec->sid, newsid, 3269 sid, isec->sclass); 3270 if (rc) 3271 return rc; 3272 3273 return avc_has_perm(newsid, 3274 sbsec->sid, 3275 SECCLASS_FILESYSTEM, 3276 FILESYSTEM__ASSOCIATE, 3277 &ad); 3278 } 3279 3280 static int selinux_inode_set_acl(struct mnt_idmap *idmap, 3281 struct dentry *dentry, const char *acl_name, 3282 struct posix_acl *kacl) 3283 { 3284 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3285 } 3286 3287 static int selinux_inode_get_acl(struct mnt_idmap *idmap, 3288 struct dentry *dentry, const char *acl_name) 3289 { 3290 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); 3291 } 3292 3293 static int selinux_inode_remove_acl(struct mnt_idmap *idmap, 3294 struct dentry *dentry, const char *acl_name) 3295 { 3296 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3297 } 3298 3299 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3300 const void *value, size_t size, 3301 int flags) 3302 { 3303 struct inode *inode = d_backing_inode(dentry); 3304 struct inode_security_struct *isec; 3305 u32 newsid; 3306 int rc; 3307 3308 if (strcmp(name, XATTR_NAME_SELINUX)) { 3309 /* Not an attribute we recognize, so nothing to do. */ 3310 return; 3311 } 3312 3313 if (!selinux_initialized()) { 3314 /* If we haven't even been initialized, then we can't validate 3315 * against a policy, so leave the label as invalid. It may 3316 * resolve to a valid label on the next revalidation try if 3317 * we've since initialized. 3318 */ 3319 return; 3320 } 3321 3322 rc = security_context_to_sid_force(value, size, 3323 &newsid); 3324 if (rc) { 3325 pr_err("SELinux: unable to map context to SID" 3326 "for (%s, %lu), rc=%d\n", 3327 inode->i_sb->s_id, inode->i_ino, -rc); 3328 return; 3329 } 3330 3331 isec = backing_inode_security(dentry); 3332 spin_lock(&isec->lock); 3333 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3334 isec->sid = newsid; 3335 isec->initialized = LABEL_INITIALIZED; 3336 spin_unlock(&isec->lock); 3337 } 3338 3339 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3340 { 3341 const struct cred *cred = current_cred(); 3342 3343 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3344 } 3345 3346 static int selinux_inode_listxattr(struct dentry *dentry) 3347 { 3348 const struct cred *cred = current_cred(); 3349 3350 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3351 } 3352 3353 static int selinux_inode_removexattr(struct mnt_idmap *idmap, 3354 struct dentry *dentry, const char *name) 3355 { 3356 if (strcmp(name, XATTR_NAME_SELINUX)) { 3357 int rc = cap_inode_removexattr(idmap, dentry, name); 3358 if (rc) 3359 return rc; 3360 3361 /* Not an attribute we recognize, so just check the 3362 ordinary setattr permission. */ 3363 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3364 } 3365 3366 if (!selinux_initialized()) 3367 return 0; 3368 3369 /* No one is allowed to remove a SELinux security label. 3370 You can change the label, but all data must be labeled. */ 3371 return -EACCES; 3372 } 3373 3374 static int selinux_path_notify(const struct path *path, u64 mask, 3375 unsigned int obj_type) 3376 { 3377 int ret; 3378 u32 perm; 3379 3380 struct common_audit_data ad; 3381 3382 ad.type = LSM_AUDIT_DATA_PATH; 3383 ad.u.path = *path; 3384 3385 /* 3386 * Set permission needed based on the type of mark being set. 3387 * Performs an additional check for sb watches. 3388 */ 3389 switch (obj_type) { 3390 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3391 perm = FILE__WATCH_MOUNT; 3392 break; 3393 case FSNOTIFY_OBJ_TYPE_SB: 3394 perm = FILE__WATCH_SB; 3395 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3396 FILESYSTEM__WATCH, &ad); 3397 if (ret) 3398 return ret; 3399 break; 3400 case FSNOTIFY_OBJ_TYPE_INODE: 3401 perm = FILE__WATCH; 3402 break; 3403 default: 3404 return -EINVAL; 3405 } 3406 3407 /* blocking watches require the file:watch_with_perm permission */ 3408 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3409 perm |= FILE__WATCH_WITH_PERM; 3410 3411 /* watches on read-like events need the file:watch_reads permission */ 3412 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3413 perm |= FILE__WATCH_READS; 3414 3415 return path_has_perm(current_cred(), path, perm); 3416 } 3417 3418 /* 3419 * Copy the inode security context value to the user. 3420 * 3421 * Permission check is handled by selinux_inode_getxattr hook. 3422 */ 3423 static int selinux_inode_getsecurity(struct mnt_idmap *idmap, 3424 struct inode *inode, const char *name, 3425 void **buffer, bool alloc) 3426 { 3427 u32 size; 3428 int error; 3429 char *context = NULL; 3430 struct inode_security_struct *isec; 3431 3432 /* 3433 * If we're not initialized yet, then we can't validate contexts, so 3434 * just let vfs_getxattr fall back to using the on-disk xattr. 3435 */ 3436 if (!selinux_initialized() || 3437 strcmp(name, XATTR_SELINUX_SUFFIX)) 3438 return -EOPNOTSUPP; 3439 3440 /* 3441 * If the caller has CAP_MAC_ADMIN, then get the raw context 3442 * value even if it is not defined by current policy; otherwise, 3443 * use the in-core value under current policy. 3444 * Use the non-auditing forms of the permission checks since 3445 * getxattr may be called by unprivileged processes commonly 3446 * and lack of permission just means that we fall back to the 3447 * in-core context value, not a denial. 3448 */ 3449 isec = inode_security(inode); 3450 if (has_cap_mac_admin(false)) 3451 error = security_sid_to_context_force(isec->sid, &context, 3452 &size); 3453 else 3454 error = security_sid_to_context(isec->sid, 3455 &context, &size); 3456 if (error) 3457 return error; 3458 error = size; 3459 if (alloc) { 3460 *buffer = context; 3461 goto out_nofree; 3462 } 3463 kfree(context); 3464 out_nofree: 3465 return error; 3466 } 3467 3468 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3469 const void *value, size_t size, int flags) 3470 { 3471 struct inode_security_struct *isec = inode_security_novalidate(inode); 3472 struct superblock_security_struct *sbsec; 3473 u32 newsid; 3474 int rc; 3475 3476 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3477 return -EOPNOTSUPP; 3478 3479 sbsec = selinux_superblock(inode->i_sb); 3480 if (!(sbsec->flags & SBLABEL_MNT)) 3481 return -EOPNOTSUPP; 3482 3483 if (!value || !size) 3484 return -EACCES; 3485 3486 rc = security_context_to_sid(value, size, &newsid, 3487 GFP_KERNEL); 3488 if (rc) 3489 return rc; 3490 3491 spin_lock(&isec->lock); 3492 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3493 isec->sid = newsid; 3494 isec->initialized = LABEL_INITIALIZED; 3495 spin_unlock(&isec->lock); 3496 return 0; 3497 } 3498 3499 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3500 { 3501 const int len = sizeof(XATTR_NAME_SELINUX); 3502 3503 if (!selinux_initialized()) 3504 return 0; 3505 3506 if (buffer && len <= buffer_size) 3507 memcpy(buffer, XATTR_NAME_SELINUX, len); 3508 return len; 3509 } 3510 3511 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3512 { 3513 struct inode_security_struct *isec = inode_security_novalidate(inode); 3514 *secid = isec->sid; 3515 } 3516 3517 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3518 { 3519 u32 sid; 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_getsecid(d_inode(src), &sid); 3532 tsec->create_sid = sid; 3533 *new = new_creds; 3534 return 0; 3535 } 3536 3537 static int selinux_inode_copy_up_xattr(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, we have to filter out SELinux-related xattrs. 3542 */ 3543 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3544 return 1; /* Discard */ 3545 /* 3546 * Any other attribute apart from SELINUX is not claimed, supported 3547 * by selinux. 3548 */ 3549 return -EOPNOTSUPP; 3550 } 3551 3552 /* kernfs node operations */ 3553 3554 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3555 struct kernfs_node *kn) 3556 { 3557 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3558 u32 parent_sid, newsid, clen; 3559 int rc; 3560 char *context; 3561 3562 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3563 if (rc == -ENODATA) 3564 return 0; 3565 else if (rc < 0) 3566 return rc; 3567 3568 clen = (u32)rc; 3569 context = kmalloc(clen, GFP_KERNEL); 3570 if (!context) 3571 return -ENOMEM; 3572 3573 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3574 if (rc < 0) { 3575 kfree(context); 3576 return rc; 3577 } 3578 3579 rc = security_context_to_sid(context, clen, &parent_sid, 3580 GFP_KERNEL); 3581 kfree(context); 3582 if (rc) 3583 return rc; 3584 3585 if (tsec->create_sid) { 3586 newsid = tsec->create_sid; 3587 } else { 3588 u16 secclass = inode_mode_to_security_class(kn->mode); 3589 struct qstr q; 3590 3591 q.name = kn->name; 3592 q.hash_len = hashlen_string(kn_dir, kn->name); 3593 3594 rc = security_transition_sid(tsec->sid, 3595 parent_sid, secclass, &q, 3596 &newsid); 3597 if (rc) 3598 return rc; 3599 } 3600 3601 rc = security_sid_to_context_force(newsid, 3602 &context, &clen); 3603 if (rc) 3604 return rc; 3605 3606 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3607 XATTR_CREATE); 3608 kfree(context); 3609 return rc; 3610 } 3611 3612 3613 /* file security operations */ 3614 3615 static int selinux_revalidate_file_permission(struct file *file, int mask) 3616 { 3617 const struct cred *cred = current_cred(); 3618 struct inode *inode = file_inode(file); 3619 3620 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3621 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3622 mask |= MAY_APPEND; 3623 3624 return file_has_perm(cred, file, 3625 file_mask_to_av(inode->i_mode, mask)); 3626 } 3627 3628 static int selinux_file_permission(struct file *file, int mask) 3629 { 3630 struct inode *inode = file_inode(file); 3631 struct file_security_struct *fsec = selinux_file(file); 3632 struct inode_security_struct *isec; 3633 u32 sid = current_sid(); 3634 3635 if (!mask) 3636 /* No permission to check. Existence test. */ 3637 return 0; 3638 3639 isec = inode_security(inode); 3640 if (sid == fsec->sid && fsec->isid == isec->sid && 3641 fsec->pseqno == avc_policy_seqno()) 3642 /* No change since file_open check. */ 3643 return 0; 3644 3645 return selinux_revalidate_file_permission(file, mask); 3646 } 3647 3648 static int selinux_file_alloc_security(struct file *file) 3649 { 3650 struct file_security_struct *fsec = selinux_file(file); 3651 u32 sid = current_sid(); 3652 3653 fsec->sid = sid; 3654 fsec->fown_sid = sid; 3655 3656 return 0; 3657 } 3658 3659 /* 3660 * Check whether a task has the ioctl permission and cmd 3661 * operation to an inode. 3662 */ 3663 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3664 u32 requested, u16 cmd) 3665 { 3666 struct common_audit_data ad; 3667 struct file_security_struct *fsec = selinux_file(file); 3668 struct inode *inode = file_inode(file); 3669 struct inode_security_struct *isec; 3670 struct lsm_ioctlop_audit ioctl; 3671 u32 ssid = cred_sid(cred); 3672 int rc; 3673 u8 driver = cmd >> 8; 3674 u8 xperm = cmd & 0xff; 3675 3676 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3677 ad.u.op = &ioctl; 3678 ad.u.op->cmd = cmd; 3679 ad.u.op->path = file->f_path; 3680 3681 if (ssid != fsec->sid) { 3682 rc = avc_has_perm(ssid, fsec->sid, 3683 SECCLASS_FD, 3684 FD__USE, 3685 &ad); 3686 if (rc) 3687 goto out; 3688 } 3689 3690 if (unlikely(IS_PRIVATE(inode))) 3691 return 0; 3692 3693 isec = inode_security(inode); 3694 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3695 requested, driver, xperm, &ad); 3696 out: 3697 return rc; 3698 } 3699 3700 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3701 unsigned long arg) 3702 { 3703 const struct cred *cred = current_cred(); 3704 int error = 0; 3705 3706 switch (cmd) { 3707 case FIONREAD: 3708 case FIBMAP: 3709 case FIGETBSZ: 3710 case FS_IOC_GETFLAGS: 3711 case FS_IOC_GETVERSION: 3712 error = file_has_perm(cred, file, FILE__GETATTR); 3713 break; 3714 3715 case FS_IOC_SETFLAGS: 3716 case FS_IOC_SETVERSION: 3717 error = file_has_perm(cred, file, FILE__SETATTR); 3718 break; 3719 3720 /* sys_ioctl() checks */ 3721 case FIONBIO: 3722 case FIOASYNC: 3723 error = file_has_perm(cred, file, 0); 3724 break; 3725 3726 case KDSKBENT: 3727 case KDSKBSENT: 3728 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3729 CAP_OPT_NONE, true); 3730 break; 3731 3732 case FIOCLEX: 3733 case FIONCLEX: 3734 if (!selinux_policycap_ioctl_skip_cloexec()) 3735 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3736 break; 3737 3738 /* default case assumes that the command will go 3739 * to the file's ioctl() function. 3740 */ 3741 default: 3742 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3743 } 3744 return error; 3745 } 3746 3747 static int default_noexec __ro_after_init; 3748 3749 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3750 { 3751 const struct cred *cred = current_cred(); 3752 u32 sid = cred_sid(cred); 3753 int rc = 0; 3754 3755 if (default_noexec && 3756 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3757 (!shared && (prot & PROT_WRITE)))) { 3758 /* 3759 * We are making executable an anonymous mapping or a 3760 * private file mapping that will also be writable. 3761 * This has an additional check. 3762 */ 3763 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3764 PROCESS__EXECMEM, NULL); 3765 if (rc) 3766 goto error; 3767 } 3768 3769 if (file) { 3770 /* read access is always possible with a mapping */ 3771 u32 av = FILE__READ; 3772 3773 /* write access only matters if the mapping is shared */ 3774 if (shared && (prot & PROT_WRITE)) 3775 av |= FILE__WRITE; 3776 3777 if (prot & PROT_EXEC) 3778 av |= FILE__EXECUTE; 3779 3780 return file_has_perm(cred, file, av); 3781 } 3782 3783 error: 3784 return rc; 3785 } 3786 3787 static int selinux_mmap_addr(unsigned long addr) 3788 { 3789 int rc = 0; 3790 3791 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3792 u32 sid = current_sid(); 3793 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3794 MEMPROTECT__MMAP_ZERO, NULL); 3795 } 3796 3797 return rc; 3798 } 3799 3800 static int selinux_mmap_file(struct file *file, 3801 unsigned long reqprot __always_unused, 3802 unsigned long prot, unsigned long flags) 3803 { 3804 struct common_audit_data ad; 3805 int rc; 3806 3807 if (file) { 3808 ad.type = LSM_AUDIT_DATA_FILE; 3809 ad.u.file = file; 3810 rc = inode_has_perm(current_cred(), file_inode(file), 3811 FILE__MAP, &ad); 3812 if (rc) 3813 return rc; 3814 } 3815 3816 return file_map_prot_check(file, prot, 3817 (flags & MAP_TYPE) == MAP_SHARED); 3818 } 3819 3820 static int selinux_file_mprotect(struct vm_area_struct *vma, 3821 unsigned long reqprot __always_unused, 3822 unsigned long prot) 3823 { 3824 const struct cred *cred = current_cred(); 3825 u32 sid = cred_sid(cred); 3826 3827 if (default_noexec && 3828 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3829 int rc = 0; 3830 if (vma_is_initial_heap(vma)) { 3831 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3832 PROCESS__EXECHEAP, NULL); 3833 } else if (!vma->vm_file && (vma_is_initial_stack(vma) || 3834 vma_is_stack_for_current(vma))) { 3835 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3836 PROCESS__EXECSTACK, NULL); 3837 } else if (vma->vm_file && vma->anon_vma) { 3838 /* 3839 * We are making executable a file mapping that has 3840 * had some COW done. Since pages might have been 3841 * written, check ability to execute the possibly 3842 * modified content. This typically should only 3843 * occur for text relocations. 3844 */ 3845 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3846 } 3847 if (rc) 3848 return rc; 3849 } 3850 3851 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3852 } 3853 3854 static int selinux_file_lock(struct file *file, unsigned int cmd) 3855 { 3856 const struct cred *cred = current_cred(); 3857 3858 return file_has_perm(cred, file, FILE__LOCK); 3859 } 3860 3861 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3862 unsigned long arg) 3863 { 3864 const struct cred *cred = current_cred(); 3865 int err = 0; 3866 3867 switch (cmd) { 3868 case F_SETFL: 3869 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3870 err = file_has_perm(cred, file, FILE__WRITE); 3871 break; 3872 } 3873 fallthrough; 3874 case F_SETOWN: 3875 case F_SETSIG: 3876 case F_GETFL: 3877 case F_GETOWN: 3878 case F_GETSIG: 3879 case F_GETOWNER_UIDS: 3880 /* Just check FD__USE permission */ 3881 err = file_has_perm(cred, file, 0); 3882 break; 3883 case F_GETLK: 3884 case F_SETLK: 3885 case F_SETLKW: 3886 case F_OFD_GETLK: 3887 case F_OFD_SETLK: 3888 case F_OFD_SETLKW: 3889 #if BITS_PER_LONG == 32 3890 case F_GETLK64: 3891 case F_SETLK64: 3892 case F_SETLKW64: 3893 #endif 3894 err = file_has_perm(cred, file, FILE__LOCK); 3895 break; 3896 } 3897 3898 return err; 3899 } 3900 3901 static void selinux_file_set_fowner(struct file *file) 3902 { 3903 struct file_security_struct *fsec; 3904 3905 fsec = selinux_file(file); 3906 fsec->fown_sid = current_sid(); 3907 } 3908 3909 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3910 struct fown_struct *fown, int signum) 3911 { 3912 struct file *file; 3913 u32 sid = task_sid_obj(tsk); 3914 u32 perm; 3915 struct file_security_struct *fsec; 3916 3917 /* struct fown_struct is never outside the context of a struct file */ 3918 file = container_of(fown, struct file, f_owner); 3919 3920 fsec = selinux_file(file); 3921 3922 if (!signum) 3923 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3924 else 3925 perm = signal_to_av(signum); 3926 3927 return avc_has_perm(fsec->fown_sid, sid, 3928 SECCLASS_PROCESS, perm, NULL); 3929 } 3930 3931 static int selinux_file_receive(struct file *file) 3932 { 3933 const struct cred *cred = current_cred(); 3934 3935 return file_has_perm(cred, file, file_to_av(file)); 3936 } 3937 3938 static int selinux_file_open(struct file *file) 3939 { 3940 struct file_security_struct *fsec; 3941 struct inode_security_struct *isec; 3942 3943 fsec = selinux_file(file); 3944 isec = inode_security(file_inode(file)); 3945 /* 3946 * Save inode label and policy sequence number 3947 * at open-time so that selinux_file_permission 3948 * can determine whether revalidation is necessary. 3949 * Task label is already saved in the file security 3950 * struct as its SID. 3951 */ 3952 fsec->isid = isec->sid; 3953 fsec->pseqno = avc_policy_seqno(); 3954 /* 3955 * Since the inode label or policy seqno may have changed 3956 * between the selinux_inode_permission check and the saving 3957 * of state above, recheck that access is still permitted. 3958 * Otherwise, access might never be revalidated against the 3959 * new inode label or new policy. 3960 * This check is not redundant - do not remove. 3961 */ 3962 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3963 } 3964 3965 /* task security operations */ 3966 3967 static int selinux_task_alloc(struct task_struct *task, 3968 unsigned long clone_flags) 3969 { 3970 u32 sid = current_sid(); 3971 3972 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3973 } 3974 3975 /* 3976 * prepare a new set of credentials for modification 3977 */ 3978 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3979 gfp_t gfp) 3980 { 3981 const struct task_security_struct *old_tsec = selinux_cred(old); 3982 struct task_security_struct *tsec = selinux_cred(new); 3983 3984 *tsec = *old_tsec; 3985 return 0; 3986 } 3987 3988 /* 3989 * transfer the SELinux data to a blank set of creds 3990 */ 3991 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3992 { 3993 const struct task_security_struct *old_tsec = selinux_cred(old); 3994 struct task_security_struct *tsec = selinux_cred(new); 3995 3996 *tsec = *old_tsec; 3997 } 3998 3999 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 4000 { 4001 *secid = cred_sid(c); 4002 } 4003 4004 /* 4005 * set the security data for a kernel service 4006 * - all the creation contexts are set to unlabelled 4007 */ 4008 static int selinux_kernel_act_as(struct cred *new, u32 secid) 4009 { 4010 struct task_security_struct *tsec = selinux_cred(new); 4011 u32 sid = current_sid(); 4012 int ret; 4013 4014 ret = avc_has_perm(sid, secid, 4015 SECCLASS_KERNEL_SERVICE, 4016 KERNEL_SERVICE__USE_AS_OVERRIDE, 4017 NULL); 4018 if (ret == 0) { 4019 tsec->sid = secid; 4020 tsec->create_sid = 0; 4021 tsec->keycreate_sid = 0; 4022 tsec->sockcreate_sid = 0; 4023 } 4024 return ret; 4025 } 4026 4027 /* 4028 * set the file creation context in a security record to the same as the 4029 * objective context of the specified inode 4030 */ 4031 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4032 { 4033 struct inode_security_struct *isec = inode_security(inode); 4034 struct task_security_struct *tsec = selinux_cred(new); 4035 u32 sid = current_sid(); 4036 int ret; 4037 4038 ret = avc_has_perm(sid, isec->sid, 4039 SECCLASS_KERNEL_SERVICE, 4040 KERNEL_SERVICE__CREATE_FILES_AS, 4041 NULL); 4042 4043 if (ret == 0) 4044 tsec->create_sid = isec->sid; 4045 return ret; 4046 } 4047 4048 static int selinux_kernel_module_request(char *kmod_name) 4049 { 4050 struct common_audit_data ad; 4051 4052 ad.type = LSM_AUDIT_DATA_KMOD; 4053 ad.u.kmod_name = kmod_name; 4054 4055 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4056 SYSTEM__MODULE_REQUEST, &ad); 4057 } 4058 4059 static int selinux_kernel_module_from_file(struct file *file) 4060 { 4061 struct common_audit_data ad; 4062 struct inode_security_struct *isec; 4063 struct file_security_struct *fsec; 4064 u32 sid = current_sid(); 4065 int rc; 4066 4067 /* init_module */ 4068 if (file == NULL) 4069 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 4070 SYSTEM__MODULE_LOAD, NULL); 4071 4072 /* finit_module */ 4073 4074 ad.type = LSM_AUDIT_DATA_FILE; 4075 ad.u.file = file; 4076 4077 fsec = selinux_file(file); 4078 if (sid != fsec->sid) { 4079 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4080 if (rc) 4081 return rc; 4082 } 4083 4084 isec = inode_security(file_inode(file)); 4085 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 4086 SYSTEM__MODULE_LOAD, &ad); 4087 } 4088 4089 static int selinux_kernel_read_file(struct file *file, 4090 enum kernel_read_file_id id, 4091 bool contents) 4092 { 4093 int rc = 0; 4094 4095 switch (id) { 4096 case READING_MODULE: 4097 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4098 break; 4099 default: 4100 break; 4101 } 4102 4103 return rc; 4104 } 4105 4106 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4107 { 4108 int rc = 0; 4109 4110 switch (id) { 4111 case LOADING_MODULE: 4112 rc = selinux_kernel_module_from_file(NULL); 4113 break; 4114 default: 4115 break; 4116 } 4117 4118 return rc; 4119 } 4120 4121 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4122 { 4123 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4124 PROCESS__SETPGID, NULL); 4125 } 4126 4127 static int selinux_task_getpgid(struct task_struct *p) 4128 { 4129 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4130 PROCESS__GETPGID, NULL); 4131 } 4132 4133 static int selinux_task_getsid(struct task_struct *p) 4134 { 4135 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4136 PROCESS__GETSESSION, NULL); 4137 } 4138 4139 static void selinux_current_getsecid_subj(u32 *secid) 4140 { 4141 *secid = current_sid(); 4142 } 4143 4144 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) 4145 { 4146 *secid = task_sid_obj(p); 4147 } 4148 4149 static int selinux_task_setnice(struct task_struct *p, int nice) 4150 { 4151 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4152 PROCESS__SETSCHED, NULL); 4153 } 4154 4155 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4156 { 4157 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4158 PROCESS__SETSCHED, NULL); 4159 } 4160 4161 static int selinux_task_getioprio(struct task_struct *p) 4162 { 4163 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4164 PROCESS__GETSCHED, NULL); 4165 } 4166 4167 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4168 unsigned int flags) 4169 { 4170 u32 av = 0; 4171 4172 if (!flags) 4173 return 0; 4174 if (flags & LSM_PRLIMIT_WRITE) 4175 av |= PROCESS__SETRLIMIT; 4176 if (flags & LSM_PRLIMIT_READ) 4177 av |= PROCESS__GETRLIMIT; 4178 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4179 SECCLASS_PROCESS, av, NULL); 4180 } 4181 4182 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4183 struct rlimit *new_rlim) 4184 { 4185 struct rlimit *old_rlim = p->signal->rlim + resource; 4186 4187 /* Control the ability to change the hard limit (whether 4188 lowering or raising it), so that the hard limit can 4189 later be used as a safe reset point for the soft limit 4190 upon context transitions. See selinux_bprm_committing_creds. */ 4191 if (old_rlim->rlim_max != new_rlim->rlim_max) 4192 return avc_has_perm(current_sid(), task_sid_obj(p), 4193 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4194 4195 return 0; 4196 } 4197 4198 static int selinux_task_setscheduler(struct task_struct *p) 4199 { 4200 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4201 PROCESS__SETSCHED, NULL); 4202 } 4203 4204 static int selinux_task_getscheduler(struct task_struct *p) 4205 { 4206 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4207 PROCESS__GETSCHED, NULL); 4208 } 4209 4210 static int selinux_task_movememory(struct task_struct *p) 4211 { 4212 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4213 PROCESS__SETSCHED, NULL); 4214 } 4215 4216 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4217 int sig, const struct cred *cred) 4218 { 4219 u32 secid; 4220 u32 perm; 4221 4222 if (!sig) 4223 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4224 else 4225 perm = signal_to_av(sig); 4226 if (!cred) 4227 secid = current_sid(); 4228 else 4229 secid = cred_sid(cred); 4230 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4231 } 4232 4233 static void selinux_task_to_inode(struct task_struct *p, 4234 struct inode *inode) 4235 { 4236 struct inode_security_struct *isec = selinux_inode(inode); 4237 u32 sid = task_sid_obj(p); 4238 4239 spin_lock(&isec->lock); 4240 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4241 isec->sid = sid; 4242 isec->initialized = LABEL_INITIALIZED; 4243 spin_unlock(&isec->lock); 4244 } 4245 4246 static int selinux_userns_create(const struct cred *cred) 4247 { 4248 u32 sid = current_sid(); 4249 4250 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4251 USER_NAMESPACE__CREATE, NULL); 4252 } 4253 4254 /* Returns error only if unable to parse addresses */ 4255 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4256 struct common_audit_data *ad, u8 *proto) 4257 { 4258 int offset, ihlen, ret = -EINVAL; 4259 struct iphdr _iph, *ih; 4260 4261 offset = skb_network_offset(skb); 4262 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4263 if (ih == NULL) 4264 goto out; 4265 4266 ihlen = ih->ihl * 4; 4267 if (ihlen < sizeof(_iph)) 4268 goto out; 4269 4270 ad->u.net->v4info.saddr = ih->saddr; 4271 ad->u.net->v4info.daddr = ih->daddr; 4272 ret = 0; 4273 4274 if (proto) 4275 *proto = ih->protocol; 4276 4277 switch (ih->protocol) { 4278 case IPPROTO_TCP: { 4279 struct tcphdr _tcph, *th; 4280 4281 if (ntohs(ih->frag_off) & IP_OFFSET) 4282 break; 4283 4284 offset += ihlen; 4285 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4286 if (th == NULL) 4287 break; 4288 4289 ad->u.net->sport = th->source; 4290 ad->u.net->dport = th->dest; 4291 break; 4292 } 4293 4294 case IPPROTO_UDP: { 4295 struct udphdr _udph, *uh; 4296 4297 if (ntohs(ih->frag_off) & IP_OFFSET) 4298 break; 4299 4300 offset += ihlen; 4301 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4302 if (uh == NULL) 4303 break; 4304 4305 ad->u.net->sport = uh->source; 4306 ad->u.net->dport = uh->dest; 4307 break; 4308 } 4309 4310 case IPPROTO_DCCP: { 4311 struct dccp_hdr _dccph, *dh; 4312 4313 if (ntohs(ih->frag_off) & IP_OFFSET) 4314 break; 4315 4316 offset += ihlen; 4317 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4318 if (dh == NULL) 4319 break; 4320 4321 ad->u.net->sport = dh->dccph_sport; 4322 ad->u.net->dport = dh->dccph_dport; 4323 break; 4324 } 4325 4326 #if IS_ENABLED(CONFIG_IP_SCTP) 4327 case IPPROTO_SCTP: { 4328 struct sctphdr _sctph, *sh; 4329 4330 if (ntohs(ih->frag_off) & IP_OFFSET) 4331 break; 4332 4333 offset += ihlen; 4334 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4335 if (sh == NULL) 4336 break; 4337 4338 ad->u.net->sport = sh->source; 4339 ad->u.net->dport = sh->dest; 4340 break; 4341 } 4342 #endif 4343 default: 4344 break; 4345 } 4346 out: 4347 return ret; 4348 } 4349 4350 #if IS_ENABLED(CONFIG_IPV6) 4351 4352 /* Returns error only if unable to parse addresses */ 4353 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4354 struct common_audit_data *ad, u8 *proto) 4355 { 4356 u8 nexthdr; 4357 int ret = -EINVAL, offset; 4358 struct ipv6hdr _ipv6h, *ip6; 4359 __be16 frag_off; 4360 4361 offset = skb_network_offset(skb); 4362 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4363 if (ip6 == NULL) 4364 goto out; 4365 4366 ad->u.net->v6info.saddr = ip6->saddr; 4367 ad->u.net->v6info.daddr = ip6->daddr; 4368 ret = 0; 4369 4370 nexthdr = ip6->nexthdr; 4371 offset += sizeof(_ipv6h); 4372 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4373 if (offset < 0) 4374 goto out; 4375 4376 if (proto) 4377 *proto = nexthdr; 4378 4379 switch (nexthdr) { 4380 case IPPROTO_TCP: { 4381 struct tcphdr _tcph, *th; 4382 4383 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4384 if (th == NULL) 4385 break; 4386 4387 ad->u.net->sport = th->source; 4388 ad->u.net->dport = th->dest; 4389 break; 4390 } 4391 4392 case IPPROTO_UDP: { 4393 struct udphdr _udph, *uh; 4394 4395 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4396 if (uh == NULL) 4397 break; 4398 4399 ad->u.net->sport = uh->source; 4400 ad->u.net->dport = uh->dest; 4401 break; 4402 } 4403 4404 case IPPROTO_DCCP: { 4405 struct dccp_hdr _dccph, *dh; 4406 4407 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4408 if (dh == NULL) 4409 break; 4410 4411 ad->u.net->sport = dh->dccph_sport; 4412 ad->u.net->dport = dh->dccph_dport; 4413 break; 4414 } 4415 4416 #if IS_ENABLED(CONFIG_IP_SCTP) 4417 case IPPROTO_SCTP: { 4418 struct sctphdr _sctph, *sh; 4419 4420 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4421 if (sh == NULL) 4422 break; 4423 4424 ad->u.net->sport = sh->source; 4425 ad->u.net->dport = sh->dest; 4426 break; 4427 } 4428 #endif 4429 /* includes fragments */ 4430 default: 4431 break; 4432 } 4433 out: 4434 return ret; 4435 } 4436 4437 #endif /* IPV6 */ 4438 4439 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4440 char **_addrp, int src, u8 *proto) 4441 { 4442 char *addrp; 4443 int ret; 4444 4445 switch (ad->u.net->family) { 4446 case PF_INET: 4447 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4448 if (ret) 4449 goto parse_error; 4450 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4451 &ad->u.net->v4info.daddr); 4452 goto okay; 4453 4454 #if IS_ENABLED(CONFIG_IPV6) 4455 case PF_INET6: 4456 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4457 if (ret) 4458 goto parse_error; 4459 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4460 &ad->u.net->v6info.daddr); 4461 goto okay; 4462 #endif /* IPV6 */ 4463 default: 4464 addrp = NULL; 4465 goto okay; 4466 } 4467 4468 parse_error: 4469 pr_warn( 4470 "SELinux: failure in selinux_parse_skb()," 4471 " unable to parse packet\n"); 4472 return ret; 4473 4474 okay: 4475 if (_addrp) 4476 *_addrp = addrp; 4477 return 0; 4478 } 4479 4480 /** 4481 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4482 * @skb: the packet 4483 * @family: protocol family 4484 * @sid: the packet's peer label SID 4485 * 4486 * Description: 4487 * Check the various different forms of network peer labeling and determine 4488 * the peer label/SID for the packet; most of the magic actually occurs in 4489 * the security server function security_net_peersid_cmp(). The function 4490 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4491 * or -EACCES if @sid is invalid due to inconsistencies with the different 4492 * peer labels. 4493 * 4494 */ 4495 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4496 { 4497 int err; 4498 u32 xfrm_sid; 4499 u32 nlbl_sid; 4500 u32 nlbl_type; 4501 4502 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4503 if (unlikely(err)) 4504 return -EACCES; 4505 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4506 if (unlikely(err)) 4507 return -EACCES; 4508 4509 err = security_net_peersid_resolve(nlbl_sid, 4510 nlbl_type, xfrm_sid, sid); 4511 if (unlikely(err)) { 4512 pr_warn( 4513 "SELinux: failure in selinux_skb_peerlbl_sid()," 4514 " unable to determine packet's peer label\n"); 4515 return -EACCES; 4516 } 4517 4518 return 0; 4519 } 4520 4521 /** 4522 * selinux_conn_sid - Determine the child socket label for a connection 4523 * @sk_sid: the parent socket's SID 4524 * @skb_sid: the packet's SID 4525 * @conn_sid: the resulting connection SID 4526 * 4527 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4528 * combined with the MLS information from @skb_sid in order to create 4529 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4530 * of @sk_sid. Returns zero on success, negative values on failure. 4531 * 4532 */ 4533 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4534 { 4535 int err = 0; 4536 4537 if (skb_sid != SECSID_NULL) 4538 err = security_sid_mls_copy(sk_sid, skb_sid, 4539 conn_sid); 4540 else 4541 *conn_sid = sk_sid; 4542 4543 return err; 4544 } 4545 4546 /* socket security operations */ 4547 4548 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4549 u16 secclass, u32 *socksid) 4550 { 4551 if (tsec->sockcreate_sid > SECSID_NULL) { 4552 *socksid = tsec->sockcreate_sid; 4553 return 0; 4554 } 4555 4556 return security_transition_sid(tsec->sid, tsec->sid, 4557 secclass, NULL, socksid); 4558 } 4559 4560 static int sock_has_perm(struct sock *sk, u32 perms) 4561 { 4562 struct sk_security_struct *sksec = sk->sk_security; 4563 struct common_audit_data ad; 4564 struct lsm_network_audit net; 4565 4566 if (sksec->sid == SECINITSID_KERNEL) 4567 return 0; 4568 4569 /* 4570 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that 4571 * inherited the kernel context from early boot used to be skipped 4572 * here, so preserve that behavior unless the capability is set. 4573 * 4574 * By setting the capability the policy signals that it is ready 4575 * for this quirk to be fixed. Note that sockets created by a kernel 4576 * thread or a usermode helper executed without a transition will 4577 * still be skipped in this check regardless of the policycap 4578 * setting. 4579 */ 4580 if (!selinux_policycap_userspace_initial_context() && 4581 sksec->sid == SECINITSID_INIT) 4582 return 0; 4583 4584 ad_net_init_from_sk(&ad, &net, sk); 4585 4586 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4587 &ad); 4588 } 4589 4590 static int selinux_socket_create(int family, int type, 4591 int protocol, int kern) 4592 { 4593 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4594 u32 newsid; 4595 u16 secclass; 4596 int rc; 4597 4598 if (kern) 4599 return 0; 4600 4601 secclass = socket_type_to_security_class(family, type, protocol); 4602 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4603 if (rc) 4604 return rc; 4605 4606 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4607 } 4608 4609 static int selinux_socket_post_create(struct socket *sock, int family, 4610 int type, int protocol, int kern) 4611 { 4612 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4613 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4614 struct sk_security_struct *sksec; 4615 u16 sclass = socket_type_to_security_class(family, type, protocol); 4616 u32 sid = SECINITSID_KERNEL; 4617 int err = 0; 4618 4619 if (!kern) { 4620 err = socket_sockcreate_sid(tsec, sclass, &sid); 4621 if (err) 4622 return err; 4623 } 4624 4625 isec->sclass = sclass; 4626 isec->sid = sid; 4627 isec->initialized = LABEL_INITIALIZED; 4628 4629 if (sock->sk) { 4630 sksec = sock->sk->sk_security; 4631 sksec->sclass = sclass; 4632 sksec->sid = sid; 4633 /* Allows detection of the first association on this socket */ 4634 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4635 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4636 4637 err = selinux_netlbl_socket_post_create(sock->sk, family); 4638 } 4639 4640 return err; 4641 } 4642 4643 static int selinux_socket_socketpair(struct socket *socka, 4644 struct socket *sockb) 4645 { 4646 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4647 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4648 4649 sksec_a->peer_sid = sksec_b->sid; 4650 sksec_b->peer_sid = sksec_a->sid; 4651 4652 return 0; 4653 } 4654 4655 /* Range of port numbers used to automatically bind. 4656 Need to determine whether we should perform a name_bind 4657 permission check between the socket and the port number. */ 4658 4659 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4660 { 4661 struct sock *sk = sock->sk; 4662 struct sk_security_struct *sksec = sk->sk_security; 4663 u16 family; 4664 int err; 4665 4666 err = sock_has_perm(sk, SOCKET__BIND); 4667 if (err) 4668 goto out; 4669 4670 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4671 family = sk->sk_family; 4672 if (family == PF_INET || family == PF_INET6) { 4673 char *addrp; 4674 struct common_audit_data ad; 4675 struct lsm_network_audit net = {0,}; 4676 struct sockaddr_in *addr4 = NULL; 4677 struct sockaddr_in6 *addr6 = NULL; 4678 u16 family_sa; 4679 unsigned short snum; 4680 u32 sid, node_perm; 4681 4682 /* 4683 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4684 * that validates multiple binding addresses. Because of this 4685 * need to check address->sa_family as it is possible to have 4686 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4687 */ 4688 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4689 return -EINVAL; 4690 family_sa = address->sa_family; 4691 switch (family_sa) { 4692 case AF_UNSPEC: 4693 case AF_INET: 4694 if (addrlen < sizeof(struct sockaddr_in)) 4695 return -EINVAL; 4696 addr4 = (struct sockaddr_in *)address; 4697 if (family_sa == AF_UNSPEC) { 4698 /* see __inet_bind(), we only want to allow 4699 * AF_UNSPEC if the address is INADDR_ANY 4700 */ 4701 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4702 goto err_af; 4703 family_sa = AF_INET; 4704 } 4705 snum = ntohs(addr4->sin_port); 4706 addrp = (char *)&addr4->sin_addr.s_addr; 4707 break; 4708 case AF_INET6: 4709 if (addrlen < SIN6_LEN_RFC2133) 4710 return -EINVAL; 4711 addr6 = (struct sockaddr_in6 *)address; 4712 snum = ntohs(addr6->sin6_port); 4713 addrp = (char *)&addr6->sin6_addr.s6_addr; 4714 break; 4715 default: 4716 goto err_af; 4717 } 4718 4719 ad.type = LSM_AUDIT_DATA_NET; 4720 ad.u.net = &net; 4721 ad.u.net->sport = htons(snum); 4722 ad.u.net->family = family_sa; 4723 4724 if (snum) { 4725 int low, high; 4726 4727 inet_get_local_port_range(sock_net(sk), &low, &high); 4728 4729 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4730 snum < low || snum > high) { 4731 err = sel_netport_sid(sk->sk_protocol, 4732 snum, &sid); 4733 if (err) 4734 goto out; 4735 err = avc_has_perm(sksec->sid, sid, 4736 sksec->sclass, 4737 SOCKET__NAME_BIND, &ad); 4738 if (err) 4739 goto out; 4740 } 4741 } 4742 4743 switch (sksec->sclass) { 4744 case SECCLASS_TCP_SOCKET: 4745 node_perm = TCP_SOCKET__NODE_BIND; 4746 break; 4747 4748 case SECCLASS_UDP_SOCKET: 4749 node_perm = UDP_SOCKET__NODE_BIND; 4750 break; 4751 4752 case SECCLASS_DCCP_SOCKET: 4753 node_perm = DCCP_SOCKET__NODE_BIND; 4754 break; 4755 4756 case SECCLASS_SCTP_SOCKET: 4757 node_perm = SCTP_SOCKET__NODE_BIND; 4758 break; 4759 4760 default: 4761 node_perm = RAWIP_SOCKET__NODE_BIND; 4762 break; 4763 } 4764 4765 err = sel_netnode_sid(addrp, family_sa, &sid); 4766 if (err) 4767 goto out; 4768 4769 if (family_sa == AF_INET) 4770 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4771 else 4772 ad.u.net->v6info.saddr = addr6->sin6_addr; 4773 4774 err = avc_has_perm(sksec->sid, sid, 4775 sksec->sclass, node_perm, &ad); 4776 if (err) 4777 goto out; 4778 } 4779 out: 4780 return err; 4781 err_af: 4782 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4783 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4784 return -EINVAL; 4785 return -EAFNOSUPPORT; 4786 } 4787 4788 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4789 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4790 */ 4791 static int selinux_socket_connect_helper(struct socket *sock, 4792 struct sockaddr *address, int addrlen) 4793 { 4794 struct sock *sk = sock->sk; 4795 struct sk_security_struct *sksec = sk->sk_security; 4796 int err; 4797 4798 err = sock_has_perm(sk, SOCKET__CONNECT); 4799 if (err) 4800 return err; 4801 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4802 return -EINVAL; 4803 4804 /* connect(AF_UNSPEC) has special handling, as it is a documented 4805 * way to disconnect the socket 4806 */ 4807 if (address->sa_family == AF_UNSPEC) 4808 return 0; 4809 4810 /* 4811 * If a TCP, DCCP or SCTP socket, check name_connect permission 4812 * for the port. 4813 */ 4814 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4815 sksec->sclass == SECCLASS_DCCP_SOCKET || 4816 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4817 struct common_audit_data ad; 4818 struct lsm_network_audit net = {0,}; 4819 struct sockaddr_in *addr4 = NULL; 4820 struct sockaddr_in6 *addr6 = NULL; 4821 unsigned short snum; 4822 u32 sid, perm; 4823 4824 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4825 * that validates multiple connect addresses. Because of this 4826 * need to check address->sa_family as it is possible to have 4827 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4828 */ 4829 switch (address->sa_family) { 4830 case AF_INET: 4831 addr4 = (struct sockaddr_in *)address; 4832 if (addrlen < sizeof(struct sockaddr_in)) 4833 return -EINVAL; 4834 snum = ntohs(addr4->sin_port); 4835 break; 4836 case AF_INET6: 4837 addr6 = (struct sockaddr_in6 *)address; 4838 if (addrlen < SIN6_LEN_RFC2133) 4839 return -EINVAL; 4840 snum = ntohs(addr6->sin6_port); 4841 break; 4842 default: 4843 /* Note that SCTP services expect -EINVAL, whereas 4844 * others expect -EAFNOSUPPORT. 4845 */ 4846 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4847 return -EINVAL; 4848 else 4849 return -EAFNOSUPPORT; 4850 } 4851 4852 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4853 if (err) 4854 return err; 4855 4856 switch (sksec->sclass) { 4857 case SECCLASS_TCP_SOCKET: 4858 perm = TCP_SOCKET__NAME_CONNECT; 4859 break; 4860 case SECCLASS_DCCP_SOCKET: 4861 perm = DCCP_SOCKET__NAME_CONNECT; 4862 break; 4863 case SECCLASS_SCTP_SOCKET: 4864 perm = SCTP_SOCKET__NAME_CONNECT; 4865 break; 4866 } 4867 4868 ad.type = LSM_AUDIT_DATA_NET; 4869 ad.u.net = &net; 4870 ad.u.net->dport = htons(snum); 4871 ad.u.net->family = address->sa_family; 4872 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4873 if (err) 4874 return err; 4875 } 4876 4877 return 0; 4878 } 4879 4880 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4881 static int selinux_socket_connect(struct socket *sock, 4882 struct sockaddr *address, int addrlen) 4883 { 4884 int err; 4885 struct sock *sk = sock->sk; 4886 4887 err = selinux_socket_connect_helper(sock, address, addrlen); 4888 if (err) 4889 return err; 4890 4891 return selinux_netlbl_socket_connect(sk, address); 4892 } 4893 4894 static int selinux_socket_listen(struct socket *sock, int backlog) 4895 { 4896 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4897 } 4898 4899 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4900 { 4901 int err; 4902 struct inode_security_struct *isec; 4903 struct inode_security_struct *newisec; 4904 u16 sclass; 4905 u32 sid; 4906 4907 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4908 if (err) 4909 return err; 4910 4911 isec = inode_security_novalidate(SOCK_INODE(sock)); 4912 spin_lock(&isec->lock); 4913 sclass = isec->sclass; 4914 sid = isec->sid; 4915 spin_unlock(&isec->lock); 4916 4917 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4918 newisec->sclass = sclass; 4919 newisec->sid = sid; 4920 newisec->initialized = LABEL_INITIALIZED; 4921 4922 return 0; 4923 } 4924 4925 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4926 int size) 4927 { 4928 return sock_has_perm(sock->sk, SOCKET__WRITE); 4929 } 4930 4931 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4932 int size, int flags) 4933 { 4934 return sock_has_perm(sock->sk, SOCKET__READ); 4935 } 4936 4937 static int selinux_socket_getsockname(struct socket *sock) 4938 { 4939 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4940 } 4941 4942 static int selinux_socket_getpeername(struct socket *sock) 4943 { 4944 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4945 } 4946 4947 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4948 { 4949 int err; 4950 4951 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4952 if (err) 4953 return err; 4954 4955 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4956 } 4957 4958 static int selinux_socket_getsockopt(struct socket *sock, int level, 4959 int optname) 4960 { 4961 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4962 } 4963 4964 static int selinux_socket_shutdown(struct socket *sock, int how) 4965 { 4966 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4967 } 4968 4969 static int selinux_socket_unix_stream_connect(struct sock *sock, 4970 struct sock *other, 4971 struct sock *newsk) 4972 { 4973 struct sk_security_struct *sksec_sock = sock->sk_security; 4974 struct sk_security_struct *sksec_other = other->sk_security; 4975 struct sk_security_struct *sksec_new = newsk->sk_security; 4976 struct common_audit_data ad; 4977 struct lsm_network_audit net; 4978 int err; 4979 4980 ad_net_init_from_sk(&ad, &net, other); 4981 4982 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4983 sksec_other->sclass, 4984 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4985 if (err) 4986 return err; 4987 4988 /* server child socket */ 4989 sksec_new->peer_sid = sksec_sock->sid; 4990 err = security_sid_mls_copy(sksec_other->sid, 4991 sksec_sock->sid, &sksec_new->sid); 4992 if (err) 4993 return err; 4994 4995 /* connecting socket */ 4996 sksec_sock->peer_sid = sksec_new->sid; 4997 4998 return 0; 4999 } 5000 5001 static int selinux_socket_unix_may_send(struct socket *sock, 5002 struct socket *other) 5003 { 5004 struct sk_security_struct *ssec = sock->sk->sk_security; 5005 struct sk_security_struct *osec = other->sk->sk_security; 5006 struct common_audit_data ad; 5007 struct lsm_network_audit net; 5008 5009 ad_net_init_from_sk(&ad, &net, other->sk); 5010 5011 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 5012 &ad); 5013 } 5014 5015 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 5016 char *addrp, u16 family, u32 peer_sid, 5017 struct common_audit_data *ad) 5018 { 5019 int err; 5020 u32 if_sid; 5021 u32 node_sid; 5022 5023 err = sel_netif_sid(ns, ifindex, &if_sid); 5024 if (err) 5025 return err; 5026 err = avc_has_perm(peer_sid, if_sid, 5027 SECCLASS_NETIF, NETIF__INGRESS, ad); 5028 if (err) 5029 return err; 5030 5031 err = sel_netnode_sid(addrp, family, &node_sid); 5032 if (err) 5033 return err; 5034 return avc_has_perm(peer_sid, node_sid, 5035 SECCLASS_NODE, NODE__RECVFROM, ad); 5036 } 5037 5038 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5039 u16 family) 5040 { 5041 int err = 0; 5042 struct sk_security_struct *sksec = sk->sk_security; 5043 u32 sk_sid = sksec->sid; 5044 struct common_audit_data ad; 5045 struct lsm_network_audit net; 5046 char *addrp; 5047 5048 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5049 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5050 if (err) 5051 return err; 5052 5053 if (selinux_secmark_enabled()) { 5054 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5055 PACKET__RECV, &ad); 5056 if (err) 5057 return err; 5058 } 5059 5060 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5061 if (err) 5062 return err; 5063 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5064 5065 return err; 5066 } 5067 5068 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5069 { 5070 int err, peerlbl_active, secmark_active; 5071 struct sk_security_struct *sksec = sk->sk_security; 5072 u16 family = sk->sk_family; 5073 u32 sk_sid = sksec->sid; 5074 struct common_audit_data ad; 5075 struct lsm_network_audit net; 5076 char *addrp; 5077 5078 if (family != PF_INET && family != PF_INET6) 5079 return 0; 5080 5081 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5082 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5083 family = PF_INET; 5084 5085 /* If any sort of compatibility mode is enabled then handoff processing 5086 * to the selinux_sock_rcv_skb_compat() function to deal with the 5087 * special handling. We do this in an attempt to keep this function 5088 * as fast and as clean as possible. */ 5089 if (!selinux_policycap_netpeer()) 5090 return selinux_sock_rcv_skb_compat(sk, skb, family); 5091 5092 secmark_active = selinux_secmark_enabled(); 5093 peerlbl_active = selinux_peerlbl_enabled(); 5094 if (!secmark_active && !peerlbl_active) 5095 return 0; 5096 5097 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5098 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5099 if (err) 5100 return err; 5101 5102 if (peerlbl_active) { 5103 u32 peer_sid; 5104 5105 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5106 if (err) 5107 return err; 5108 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5109 addrp, family, peer_sid, &ad); 5110 if (err) { 5111 selinux_netlbl_err(skb, family, err, 0); 5112 return err; 5113 } 5114 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5115 PEER__RECV, &ad); 5116 if (err) { 5117 selinux_netlbl_err(skb, family, err, 0); 5118 return err; 5119 } 5120 } 5121 5122 if (secmark_active) { 5123 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5124 PACKET__RECV, &ad); 5125 if (err) 5126 return err; 5127 } 5128 5129 return err; 5130 } 5131 5132 static int selinux_socket_getpeersec_stream(struct socket *sock, 5133 sockptr_t optval, sockptr_t optlen, 5134 unsigned int len) 5135 { 5136 int err = 0; 5137 char *scontext = NULL; 5138 u32 scontext_len; 5139 struct sk_security_struct *sksec = sock->sk->sk_security; 5140 u32 peer_sid = SECSID_NULL; 5141 5142 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5143 sksec->sclass == SECCLASS_TCP_SOCKET || 5144 sksec->sclass == SECCLASS_SCTP_SOCKET) 5145 peer_sid = sksec->peer_sid; 5146 if (peer_sid == SECSID_NULL) 5147 return -ENOPROTOOPT; 5148 5149 err = security_sid_to_context(peer_sid, &scontext, 5150 &scontext_len); 5151 if (err) 5152 return err; 5153 if (scontext_len > len) { 5154 err = -ERANGE; 5155 goto out_len; 5156 } 5157 5158 if (copy_to_sockptr(optval, scontext, scontext_len)) 5159 err = -EFAULT; 5160 out_len: 5161 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5162 err = -EFAULT; 5163 kfree(scontext); 5164 return err; 5165 } 5166 5167 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5168 { 5169 u32 peer_secid = SECSID_NULL; 5170 u16 family; 5171 struct inode_security_struct *isec; 5172 5173 if (skb && skb->protocol == htons(ETH_P_IP)) 5174 family = PF_INET; 5175 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5176 family = PF_INET6; 5177 else if (sock) 5178 family = sock->sk->sk_family; 5179 else 5180 goto out; 5181 5182 if (sock && family == PF_UNIX) { 5183 isec = inode_security_novalidate(SOCK_INODE(sock)); 5184 peer_secid = isec->sid; 5185 } else if (skb) 5186 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5187 5188 out: 5189 *secid = peer_secid; 5190 if (peer_secid == SECSID_NULL) 5191 return -EINVAL; 5192 return 0; 5193 } 5194 5195 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5196 { 5197 struct sk_security_struct *sksec; 5198 5199 sksec = kzalloc(sizeof(*sksec), priority); 5200 if (!sksec) 5201 return -ENOMEM; 5202 5203 sksec->peer_sid = SECINITSID_UNLABELED; 5204 sksec->sid = SECINITSID_UNLABELED; 5205 sksec->sclass = SECCLASS_SOCKET; 5206 selinux_netlbl_sk_security_reset(sksec); 5207 sk->sk_security = sksec; 5208 5209 return 0; 5210 } 5211 5212 static void selinux_sk_free_security(struct sock *sk) 5213 { 5214 struct sk_security_struct *sksec = sk->sk_security; 5215 5216 sk->sk_security = NULL; 5217 selinux_netlbl_sk_security_free(sksec); 5218 kfree(sksec); 5219 } 5220 5221 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5222 { 5223 struct sk_security_struct *sksec = sk->sk_security; 5224 struct sk_security_struct *newsksec = newsk->sk_security; 5225 5226 newsksec->sid = sksec->sid; 5227 newsksec->peer_sid = sksec->peer_sid; 5228 newsksec->sclass = sksec->sclass; 5229 5230 selinux_netlbl_sk_security_reset(newsksec); 5231 } 5232 5233 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5234 { 5235 if (!sk) 5236 *secid = SECINITSID_ANY_SOCKET; 5237 else { 5238 const struct sk_security_struct *sksec = sk->sk_security; 5239 5240 *secid = sksec->sid; 5241 } 5242 } 5243 5244 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5245 { 5246 struct inode_security_struct *isec = 5247 inode_security_novalidate(SOCK_INODE(parent)); 5248 struct sk_security_struct *sksec = sk->sk_security; 5249 5250 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5251 sk->sk_family == PF_UNIX) 5252 isec->sid = sksec->sid; 5253 sksec->sclass = isec->sclass; 5254 } 5255 5256 /* 5257 * Determines peer_secid for the asoc and updates socket's peer label 5258 * if it's the first association on the socket. 5259 */ 5260 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5261 struct sk_buff *skb) 5262 { 5263 struct sock *sk = asoc->base.sk; 5264 u16 family = sk->sk_family; 5265 struct sk_security_struct *sksec = sk->sk_security; 5266 struct common_audit_data ad; 5267 struct lsm_network_audit net; 5268 int err; 5269 5270 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5271 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5272 family = PF_INET; 5273 5274 if (selinux_peerlbl_enabled()) { 5275 asoc->peer_secid = SECSID_NULL; 5276 5277 /* This will return peer_sid = SECSID_NULL if there are 5278 * no peer labels, see security_net_peersid_resolve(). 5279 */ 5280 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5281 if (err) 5282 return err; 5283 5284 if (asoc->peer_secid == SECSID_NULL) 5285 asoc->peer_secid = SECINITSID_UNLABELED; 5286 } else { 5287 asoc->peer_secid = SECINITSID_UNLABELED; 5288 } 5289 5290 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5291 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5292 5293 /* Here as first association on socket. As the peer SID 5294 * was allowed by peer recv (and the netif/node checks), 5295 * then it is approved by policy and used as the primary 5296 * peer SID for getpeercon(3). 5297 */ 5298 sksec->peer_sid = asoc->peer_secid; 5299 } else if (sksec->peer_sid != asoc->peer_secid) { 5300 /* Other association peer SIDs are checked to enforce 5301 * consistency among the peer SIDs. 5302 */ 5303 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5304 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5305 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5306 &ad); 5307 if (err) 5308 return err; 5309 } 5310 return 0; 5311 } 5312 5313 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5314 * happens on an incoming connect(2), sctp_connectx(3) or 5315 * sctp_sendmsg(3) (with no association already present). 5316 */ 5317 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5318 struct sk_buff *skb) 5319 { 5320 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5321 u32 conn_sid; 5322 int err; 5323 5324 if (!selinux_policycap_extsockclass()) 5325 return 0; 5326 5327 err = selinux_sctp_process_new_assoc(asoc, skb); 5328 if (err) 5329 return err; 5330 5331 /* Compute the MLS component for the connection and store 5332 * the information in asoc. This will be used by SCTP TCP type 5333 * sockets and peeled off connections as they cause a new 5334 * socket to be generated. selinux_sctp_sk_clone() will then 5335 * plug this into the new socket. 5336 */ 5337 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5338 if (err) 5339 return err; 5340 5341 asoc->secid = conn_sid; 5342 5343 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5344 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5345 } 5346 5347 /* Called when SCTP receives a COOKIE ACK chunk as the final 5348 * response to an association request (initited by us). 5349 */ 5350 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5351 struct sk_buff *skb) 5352 { 5353 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5354 5355 if (!selinux_policycap_extsockclass()) 5356 return 0; 5357 5358 /* Inherit secid from the parent socket - this will be picked up 5359 * by selinux_sctp_sk_clone() if the association gets peeled off 5360 * into a new socket. 5361 */ 5362 asoc->secid = sksec->sid; 5363 5364 return selinux_sctp_process_new_assoc(asoc, skb); 5365 } 5366 5367 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5368 * based on their @optname. 5369 */ 5370 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5371 struct sockaddr *address, 5372 int addrlen) 5373 { 5374 int len, err = 0, walk_size = 0; 5375 void *addr_buf; 5376 struct sockaddr *addr; 5377 struct socket *sock; 5378 5379 if (!selinux_policycap_extsockclass()) 5380 return 0; 5381 5382 /* Process one or more addresses that may be IPv4 or IPv6 */ 5383 sock = sk->sk_socket; 5384 addr_buf = address; 5385 5386 while (walk_size < addrlen) { 5387 if (walk_size + sizeof(sa_family_t) > addrlen) 5388 return -EINVAL; 5389 5390 addr = addr_buf; 5391 switch (addr->sa_family) { 5392 case AF_UNSPEC: 5393 case AF_INET: 5394 len = sizeof(struct sockaddr_in); 5395 break; 5396 case AF_INET6: 5397 len = sizeof(struct sockaddr_in6); 5398 break; 5399 default: 5400 return -EINVAL; 5401 } 5402 5403 if (walk_size + len > addrlen) 5404 return -EINVAL; 5405 5406 err = -EINVAL; 5407 switch (optname) { 5408 /* Bind checks */ 5409 case SCTP_PRIMARY_ADDR: 5410 case SCTP_SET_PEER_PRIMARY_ADDR: 5411 case SCTP_SOCKOPT_BINDX_ADD: 5412 err = selinux_socket_bind(sock, addr, len); 5413 break; 5414 /* Connect checks */ 5415 case SCTP_SOCKOPT_CONNECTX: 5416 case SCTP_PARAM_SET_PRIMARY: 5417 case SCTP_PARAM_ADD_IP: 5418 case SCTP_SENDMSG_CONNECT: 5419 err = selinux_socket_connect_helper(sock, addr, len); 5420 if (err) 5421 return err; 5422 5423 /* As selinux_sctp_bind_connect() is called by the 5424 * SCTP protocol layer, the socket is already locked, 5425 * therefore selinux_netlbl_socket_connect_locked() 5426 * is called here. The situations handled are: 5427 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5428 * whenever a new IP address is added or when a new 5429 * primary address is selected. 5430 * Note that an SCTP connect(2) call happens before 5431 * the SCTP protocol layer and is handled via 5432 * selinux_socket_connect(). 5433 */ 5434 err = selinux_netlbl_socket_connect_locked(sk, addr); 5435 break; 5436 } 5437 5438 if (err) 5439 return err; 5440 5441 addr_buf += len; 5442 walk_size += len; 5443 } 5444 5445 return 0; 5446 } 5447 5448 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5449 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5450 struct sock *newsk) 5451 { 5452 struct sk_security_struct *sksec = sk->sk_security; 5453 struct sk_security_struct *newsksec = newsk->sk_security; 5454 5455 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5456 * the non-sctp clone version. 5457 */ 5458 if (!selinux_policycap_extsockclass()) 5459 return selinux_sk_clone_security(sk, newsk); 5460 5461 newsksec->sid = asoc->secid; 5462 newsksec->peer_sid = asoc->peer_secid; 5463 newsksec->sclass = sksec->sclass; 5464 selinux_netlbl_sctp_sk_clone(sk, newsk); 5465 } 5466 5467 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5468 { 5469 struct sk_security_struct *ssksec = ssk->sk_security; 5470 struct sk_security_struct *sksec = sk->sk_security; 5471 5472 ssksec->sclass = sksec->sclass; 5473 ssksec->sid = sksec->sid; 5474 5475 /* replace the existing subflow label deleting the existing one 5476 * and re-recreating a new label using the updated context 5477 */ 5478 selinux_netlbl_sk_security_free(ssksec); 5479 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5480 } 5481 5482 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5483 struct request_sock *req) 5484 { 5485 struct sk_security_struct *sksec = sk->sk_security; 5486 int err; 5487 u16 family = req->rsk_ops->family; 5488 u32 connsid; 5489 u32 peersid; 5490 5491 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5492 if (err) 5493 return err; 5494 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5495 if (err) 5496 return err; 5497 req->secid = connsid; 5498 req->peer_secid = peersid; 5499 5500 return selinux_netlbl_inet_conn_request(req, family); 5501 } 5502 5503 static void selinux_inet_csk_clone(struct sock *newsk, 5504 const struct request_sock *req) 5505 { 5506 struct sk_security_struct *newsksec = newsk->sk_security; 5507 5508 newsksec->sid = req->secid; 5509 newsksec->peer_sid = req->peer_secid; 5510 /* NOTE: Ideally, we should also get the isec->sid for the 5511 new socket in sync, but we don't have the isec available yet. 5512 So we will wait until sock_graft to do it, by which 5513 time it will have been created and available. */ 5514 5515 /* We don't need to take any sort of lock here as we are the only 5516 * thread with access to newsksec */ 5517 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5518 } 5519 5520 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5521 { 5522 u16 family = sk->sk_family; 5523 struct sk_security_struct *sksec = sk->sk_security; 5524 5525 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5526 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5527 family = PF_INET; 5528 5529 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5530 } 5531 5532 static int selinux_secmark_relabel_packet(u32 sid) 5533 { 5534 const struct task_security_struct *tsec; 5535 u32 tsid; 5536 5537 tsec = selinux_cred(current_cred()); 5538 tsid = tsec->sid; 5539 5540 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5541 NULL); 5542 } 5543 5544 static void selinux_secmark_refcount_inc(void) 5545 { 5546 atomic_inc(&selinux_secmark_refcount); 5547 } 5548 5549 static void selinux_secmark_refcount_dec(void) 5550 { 5551 atomic_dec(&selinux_secmark_refcount); 5552 } 5553 5554 static void selinux_req_classify_flow(const struct request_sock *req, 5555 struct flowi_common *flic) 5556 { 5557 flic->flowic_secid = req->secid; 5558 } 5559 5560 static int selinux_tun_dev_alloc_security(void **security) 5561 { 5562 struct tun_security_struct *tunsec; 5563 5564 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5565 if (!tunsec) 5566 return -ENOMEM; 5567 tunsec->sid = current_sid(); 5568 5569 *security = tunsec; 5570 return 0; 5571 } 5572 5573 static void selinux_tun_dev_free_security(void *security) 5574 { 5575 kfree(security); 5576 } 5577 5578 static int selinux_tun_dev_create(void) 5579 { 5580 u32 sid = current_sid(); 5581 5582 /* we aren't taking into account the "sockcreate" SID since the socket 5583 * that is being created here is not a socket in the traditional sense, 5584 * instead it is a private sock, accessible only to the kernel, and 5585 * representing a wide range of network traffic spanning multiple 5586 * connections unlike traditional sockets - check the TUN driver to 5587 * get a better understanding of why this socket is special */ 5588 5589 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5590 NULL); 5591 } 5592 5593 static int selinux_tun_dev_attach_queue(void *security) 5594 { 5595 struct tun_security_struct *tunsec = security; 5596 5597 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5598 TUN_SOCKET__ATTACH_QUEUE, NULL); 5599 } 5600 5601 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5602 { 5603 struct tun_security_struct *tunsec = security; 5604 struct sk_security_struct *sksec = sk->sk_security; 5605 5606 /* we don't currently perform any NetLabel based labeling here and it 5607 * isn't clear that we would want to do so anyway; while we could apply 5608 * labeling without the support of the TUN user the resulting labeled 5609 * traffic from the other end of the connection would almost certainly 5610 * cause confusion to the TUN user that had no idea network labeling 5611 * protocols were being used */ 5612 5613 sksec->sid = tunsec->sid; 5614 sksec->sclass = SECCLASS_TUN_SOCKET; 5615 5616 return 0; 5617 } 5618 5619 static int selinux_tun_dev_open(void *security) 5620 { 5621 struct tun_security_struct *tunsec = security; 5622 u32 sid = current_sid(); 5623 int err; 5624 5625 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5626 TUN_SOCKET__RELABELFROM, NULL); 5627 if (err) 5628 return err; 5629 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5630 TUN_SOCKET__RELABELTO, NULL); 5631 if (err) 5632 return err; 5633 tunsec->sid = sid; 5634 5635 return 0; 5636 } 5637 5638 #ifdef CONFIG_NETFILTER 5639 5640 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5641 const struct nf_hook_state *state) 5642 { 5643 int ifindex; 5644 u16 family; 5645 char *addrp; 5646 u32 peer_sid; 5647 struct common_audit_data ad; 5648 struct lsm_network_audit net; 5649 int secmark_active, peerlbl_active; 5650 5651 if (!selinux_policycap_netpeer()) 5652 return NF_ACCEPT; 5653 5654 secmark_active = selinux_secmark_enabled(); 5655 peerlbl_active = selinux_peerlbl_enabled(); 5656 if (!secmark_active && !peerlbl_active) 5657 return NF_ACCEPT; 5658 5659 family = state->pf; 5660 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5661 return NF_DROP; 5662 5663 ifindex = state->in->ifindex; 5664 ad_net_init_from_iif(&ad, &net, ifindex, family); 5665 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5666 return NF_DROP; 5667 5668 if (peerlbl_active) { 5669 int err; 5670 5671 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5672 addrp, family, peer_sid, &ad); 5673 if (err) { 5674 selinux_netlbl_err(skb, family, err, 1); 5675 return NF_DROP; 5676 } 5677 } 5678 5679 if (secmark_active) 5680 if (avc_has_perm(peer_sid, skb->secmark, 5681 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5682 return NF_DROP; 5683 5684 if (netlbl_enabled()) 5685 /* we do this in the FORWARD path and not the POST_ROUTING 5686 * path because we want to make sure we apply the necessary 5687 * labeling before IPsec is applied so we can leverage AH 5688 * protection */ 5689 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5690 return NF_DROP; 5691 5692 return NF_ACCEPT; 5693 } 5694 5695 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5696 const struct nf_hook_state *state) 5697 { 5698 struct sock *sk; 5699 u32 sid; 5700 5701 if (!netlbl_enabled()) 5702 return NF_ACCEPT; 5703 5704 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5705 * because we want to make sure we apply the necessary labeling 5706 * before IPsec is applied so we can leverage AH protection */ 5707 sk = skb->sk; 5708 if (sk) { 5709 struct sk_security_struct *sksec; 5710 5711 if (sk_listener(sk)) 5712 /* if the socket is the listening state then this 5713 * packet is a SYN-ACK packet which means it needs to 5714 * be labeled based on the connection/request_sock and 5715 * not the parent socket. unfortunately, we can't 5716 * lookup the request_sock yet as it isn't queued on 5717 * the parent socket until after the SYN-ACK is sent. 5718 * the "solution" is to simply pass the packet as-is 5719 * as any IP option based labeling should be copied 5720 * from the initial connection request (in the IP 5721 * layer). it is far from ideal, but until we get a 5722 * security label in the packet itself this is the 5723 * best we can do. */ 5724 return NF_ACCEPT; 5725 5726 /* standard practice, label using the parent socket */ 5727 sksec = sk->sk_security; 5728 sid = sksec->sid; 5729 } else 5730 sid = SECINITSID_KERNEL; 5731 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5732 return NF_DROP; 5733 5734 return NF_ACCEPT; 5735 } 5736 5737 5738 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5739 const struct nf_hook_state *state) 5740 { 5741 struct sock *sk; 5742 struct sk_security_struct *sksec; 5743 struct common_audit_data ad; 5744 struct lsm_network_audit net; 5745 u8 proto = 0; 5746 5747 sk = skb_to_full_sk(skb); 5748 if (sk == NULL) 5749 return NF_ACCEPT; 5750 sksec = sk->sk_security; 5751 5752 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5753 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5754 return NF_DROP; 5755 5756 if (selinux_secmark_enabled()) 5757 if (avc_has_perm(sksec->sid, skb->secmark, 5758 SECCLASS_PACKET, PACKET__SEND, &ad)) 5759 return NF_DROP_ERR(-ECONNREFUSED); 5760 5761 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5762 return NF_DROP_ERR(-ECONNREFUSED); 5763 5764 return NF_ACCEPT; 5765 } 5766 5767 static unsigned int selinux_ip_postroute(void *priv, 5768 struct sk_buff *skb, 5769 const struct nf_hook_state *state) 5770 { 5771 u16 family; 5772 u32 secmark_perm; 5773 u32 peer_sid; 5774 int ifindex; 5775 struct sock *sk; 5776 struct common_audit_data ad; 5777 struct lsm_network_audit net; 5778 char *addrp; 5779 int secmark_active, peerlbl_active; 5780 5781 /* If any sort of compatibility mode is enabled then handoff processing 5782 * to the selinux_ip_postroute_compat() function to deal with the 5783 * special handling. We do this in an attempt to keep this function 5784 * as fast and as clean as possible. */ 5785 if (!selinux_policycap_netpeer()) 5786 return selinux_ip_postroute_compat(skb, state); 5787 5788 secmark_active = selinux_secmark_enabled(); 5789 peerlbl_active = selinux_peerlbl_enabled(); 5790 if (!secmark_active && !peerlbl_active) 5791 return NF_ACCEPT; 5792 5793 sk = skb_to_full_sk(skb); 5794 5795 #ifdef CONFIG_XFRM 5796 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5797 * packet transformation so allow the packet to pass without any checks 5798 * since we'll have another chance to perform access control checks 5799 * when the packet is on it's final way out. 5800 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5801 * is NULL, in this case go ahead and apply access control. 5802 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5803 * TCP listening state we cannot wait until the XFRM processing 5804 * is done as we will miss out on the SA label if we do; 5805 * unfortunately, this means more work, but it is only once per 5806 * connection. */ 5807 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5808 !(sk && sk_listener(sk))) 5809 return NF_ACCEPT; 5810 #endif 5811 5812 family = state->pf; 5813 if (sk == NULL) { 5814 /* Without an associated socket the packet is either coming 5815 * from the kernel or it is being forwarded; check the packet 5816 * to determine which and if the packet is being forwarded 5817 * query the packet directly to determine the security label. */ 5818 if (skb->skb_iif) { 5819 secmark_perm = PACKET__FORWARD_OUT; 5820 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5821 return NF_DROP; 5822 } else { 5823 secmark_perm = PACKET__SEND; 5824 peer_sid = SECINITSID_KERNEL; 5825 } 5826 } else if (sk_listener(sk)) { 5827 /* Locally generated packet but the associated socket is in the 5828 * listening state which means this is a SYN-ACK packet. In 5829 * this particular case the correct security label is assigned 5830 * to the connection/request_sock but unfortunately we can't 5831 * query the request_sock as it isn't queued on the parent 5832 * socket until after the SYN-ACK packet is sent; the only 5833 * viable choice is to regenerate the label like we do in 5834 * selinux_inet_conn_request(). See also selinux_ip_output() 5835 * for similar problems. */ 5836 u32 skb_sid; 5837 struct sk_security_struct *sksec; 5838 5839 sksec = sk->sk_security; 5840 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5841 return NF_DROP; 5842 /* At this point, if the returned skb peerlbl is SECSID_NULL 5843 * and the packet has been through at least one XFRM 5844 * transformation then we must be dealing with the "final" 5845 * form of labeled IPsec packet; since we've already applied 5846 * all of our access controls on this packet we can safely 5847 * pass the packet. */ 5848 if (skb_sid == SECSID_NULL) { 5849 switch (family) { 5850 case PF_INET: 5851 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5852 return NF_ACCEPT; 5853 break; 5854 case PF_INET6: 5855 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5856 return NF_ACCEPT; 5857 break; 5858 default: 5859 return NF_DROP_ERR(-ECONNREFUSED); 5860 } 5861 } 5862 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5863 return NF_DROP; 5864 secmark_perm = PACKET__SEND; 5865 } else { 5866 /* Locally generated packet, fetch the security label from the 5867 * associated socket. */ 5868 struct sk_security_struct *sksec = sk->sk_security; 5869 peer_sid = sksec->sid; 5870 secmark_perm = PACKET__SEND; 5871 } 5872 5873 ifindex = state->out->ifindex; 5874 ad_net_init_from_iif(&ad, &net, ifindex, family); 5875 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5876 return NF_DROP; 5877 5878 if (secmark_active) 5879 if (avc_has_perm(peer_sid, skb->secmark, 5880 SECCLASS_PACKET, secmark_perm, &ad)) 5881 return NF_DROP_ERR(-ECONNREFUSED); 5882 5883 if (peerlbl_active) { 5884 u32 if_sid; 5885 u32 node_sid; 5886 5887 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5888 return NF_DROP; 5889 if (avc_has_perm(peer_sid, if_sid, 5890 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5891 return NF_DROP_ERR(-ECONNREFUSED); 5892 5893 if (sel_netnode_sid(addrp, family, &node_sid)) 5894 return NF_DROP; 5895 if (avc_has_perm(peer_sid, node_sid, 5896 SECCLASS_NODE, NODE__SENDTO, &ad)) 5897 return NF_DROP_ERR(-ECONNREFUSED); 5898 } 5899 5900 return NF_ACCEPT; 5901 } 5902 #endif /* CONFIG_NETFILTER */ 5903 5904 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5905 { 5906 int rc = 0; 5907 unsigned int msg_len; 5908 unsigned int data_len = skb->len; 5909 unsigned char *data = skb->data; 5910 struct nlmsghdr *nlh; 5911 struct sk_security_struct *sksec = sk->sk_security; 5912 u16 sclass = sksec->sclass; 5913 u32 perm; 5914 5915 while (data_len >= nlmsg_total_size(0)) { 5916 nlh = (struct nlmsghdr *)data; 5917 5918 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5919 * users which means we can't reject skb's with bogus 5920 * length fields; our solution is to follow what 5921 * netlink_rcv_skb() does and simply skip processing at 5922 * messages with length fields that are clearly junk 5923 */ 5924 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5925 return 0; 5926 5927 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5928 if (rc == 0) { 5929 rc = sock_has_perm(sk, perm); 5930 if (rc) 5931 return rc; 5932 } else if (rc == -EINVAL) { 5933 /* -EINVAL is a missing msg/perm mapping */ 5934 pr_warn_ratelimited("SELinux: unrecognized netlink" 5935 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5936 " pid=%d comm=%s\n", 5937 sk->sk_protocol, nlh->nlmsg_type, 5938 secclass_map[sclass - 1].name, 5939 task_pid_nr(current), current->comm); 5940 if (enforcing_enabled() && 5941 !security_get_allow_unknown()) 5942 return rc; 5943 rc = 0; 5944 } else if (rc == -ENOENT) { 5945 /* -ENOENT is a missing socket/class mapping, ignore */ 5946 rc = 0; 5947 } else { 5948 return rc; 5949 } 5950 5951 /* move to the next message after applying netlink padding */ 5952 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5953 if (msg_len >= data_len) 5954 return 0; 5955 data_len -= msg_len; 5956 data += msg_len; 5957 } 5958 5959 return rc; 5960 } 5961 5962 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5963 { 5964 isec->sclass = sclass; 5965 isec->sid = current_sid(); 5966 } 5967 5968 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5969 u32 perms) 5970 { 5971 struct ipc_security_struct *isec; 5972 struct common_audit_data ad; 5973 u32 sid = current_sid(); 5974 5975 isec = selinux_ipc(ipc_perms); 5976 5977 ad.type = LSM_AUDIT_DATA_IPC; 5978 ad.u.ipc_id = ipc_perms->key; 5979 5980 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 5981 } 5982 5983 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5984 { 5985 struct msg_security_struct *msec; 5986 5987 msec = selinux_msg_msg(msg); 5988 msec->sid = SECINITSID_UNLABELED; 5989 5990 return 0; 5991 } 5992 5993 /* message queue security operations */ 5994 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5995 { 5996 struct ipc_security_struct *isec; 5997 struct common_audit_data ad; 5998 u32 sid = current_sid(); 5999 6000 isec = selinux_ipc(msq); 6001 ipc_init_security(isec, SECCLASS_MSGQ); 6002 6003 ad.type = LSM_AUDIT_DATA_IPC; 6004 ad.u.ipc_id = msq->key; 6005 6006 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6007 MSGQ__CREATE, &ad); 6008 } 6009 6010 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 6011 { 6012 struct ipc_security_struct *isec; 6013 struct common_audit_data ad; 6014 u32 sid = current_sid(); 6015 6016 isec = selinux_ipc(msq); 6017 6018 ad.type = LSM_AUDIT_DATA_IPC; 6019 ad.u.ipc_id = msq->key; 6020 6021 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6022 MSGQ__ASSOCIATE, &ad); 6023 } 6024 6025 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 6026 { 6027 u32 perms; 6028 6029 switch (cmd) { 6030 case IPC_INFO: 6031 case MSG_INFO: 6032 /* No specific object, just general system-wide information. */ 6033 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6034 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6035 case IPC_STAT: 6036 case MSG_STAT: 6037 case MSG_STAT_ANY: 6038 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6039 break; 6040 case IPC_SET: 6041 perms = MSGQ__SETATTR; 6042 break; 6043 case IPC_RMID: 6044 perms = MSGQ__DESTROY; 6045 break; 6046 default: 6047 return 0; 6048 } 6049 6050 return ipc_has_perm(msq, perms); 6051 } 6052 6053 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6054 { 6055 struct ipc_security_struct *isec; 6056 struct msg_security_struct *msec; 6057 struct common_audit_data ad; 6058 u32 sid = current_sid(); 6059 int rc; 6060 6061 isec = selinux_ipc(msq); 6062 msec = selinux_msg_msg(msg); 6063 6064 /* 6065 * First time through, need to assign label to the message 6066 */ 6067 if (msec->sid == SECINITSID_UNLABELED) { 6068 /* 6069 * Compute new sid based on current process and 6070 * message queue this message will be stored in 6071 */ 6072 rc = security_transition_sid(sid, isec->sid, 6073 SECCLASS_MSG, NULL, &msec->sid); 6074 if (rc) 6075 return rc; 6076 } 6077 6078 ad.type = LSM_AUDIT_DATA_IPC; 6079 ad.u.ipc_id = msq->key; 6080 6081 /* Can this process write to the queue? */ 6082 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6083 MSGQ__WRITE, &ad); 6084 if (!rc) 6085 /* Can this process send the message */ 6086 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6087 MSG__SEND, &ad); 6088 if (!rc) 6089 /* Can the message be put in the queue? */ 6090 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6091 MSGQ__ENQUEUE, &ad); 6092 6093 return rc; 6094 } 6095 6096 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6097 struct task_struct *target, 6098 long type, int mode) 6099 { 6100 struct ipc_security_struct *isec; 6101 struct msg_security_struct *msec; 6102 struct common_audit_data ad; 6103 u32 sid = task_sid_obj(target); 6104 int rc; 6105 6106 isec = selinux_ipc(msq); 6107 msec = selinux_msg_msg(msg); 6108 6109 ad.type = LSM_AUDIT_DATA_IPC; 6110 ad.u.ipc_id = msq->key; 6111 6112 rc = avc_has_perm(sid, isec->sid, 6113 SECCLASS_MSGQ, MSGQ__READ, &ad); 6114 if (!rc) 6115 rc = avc_has_perm(sid, msec->sid, 6116 SECCLASS_MSG, MSG__RECEIVE, &ad); 6117 return rc; 6118 } 6119 6120 /* Shared Memory security operations */ 6121 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6122 { 6123 struct ipc_security_struct *isec; 6124 struct common_audit_data ad; 6125 u32 sid = current_sid(); 6126 6127 isec = selinux_ipc(shp); 6128 ipc_init_security(isec, SECCLASS_SHM); 6129 6130 ad.type = LSM_AUDIT_DATA_IPC; 6131 ad.u.ipc_id = shp->key; 6132 6133 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6134 SHM__CREATE, &ad); 6135 } 6136 6137 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6138 { 6139 struct ipc_security_struct *isec; 6140 struct common_audit_data ad; 6141 u32 sid = current_sid(); 6142 6143 isec = selinux_ipc(shp); 6144 6145 ad.type = LSM_AUDIT_DATA_IPC; 6146 ad.u.ipc_id = shp->key; 6147 6148 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6149 SHM__ASSOCIATE, &ad); 6150 } 6151 6152 /* Note, at this point, shp is locked down */ 6153 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6154 { 6155 u32 perms; 6156 6157 switch (cmd) { 6158 case IPC_INFO: 6159 case SHM_INFO: 6160 /* No specific object, just general system-wide information. */ 6161 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6162 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6163 case IPC_STAT: 6164 case SHM_STAT: 6165 case SHM_STAT_ANY: 6166 perms = SHM__GETATTR | SHM__ASSOCIATE; 6167 break; 6168 case IPC_SET: 6169 perms = SHM__SETATTR; 6170 break; 6171 case SHM_LOCK: 6172 case SHM_UNLOCK: 6173 perms = SHM__LOCK; 6174 break; 6175 case IPC_RMID: 6176 perms = SHM__DESTROY; 6177 break; 6178 default: 6179 return 0; 6180 } 6181 6182 return ipc_has_perm(shp, perms); 6183 } 6184 6185 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6186 char __user *shmaddr, int shmflg) 6187 { 6188 u32 perms; 6189 6190 if (shmflg & SHM_RDONLY) 6191 perms = SHM__READ; 6192 else 6193 perms = SHM__READ | SHM__WRITE; 6194 6195 return ipc_has_perm(shp, perms); 6196 } 6197 6198 /* Semaphore security operations */ 6199 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6200 { 6201 struct ipc_security_struct *isec; 6202 struct common_audit_data ad; 6203 u32 sid = current_sid(); 6204 6205 isec = selinux_ipc(sma); 6206 ipc_init_security(isec, SECCLASS_SEM); 6207 6208 ad.type = LSM_AUDIT_DATA_IPC; 6209 ad.u.ipc_id = sma->key; 6210 6211 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6212 SEM__CREATE, &ad); 6213 } 6214 6215 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6216 { 6217 struct ipc_security_struct *isec; 6218 struct common_audit_data ad; 6219 u32 sid = current_sid(); 6220 6221 isec = selinux_ipc(sma); 6222 6223 ad.type = LSM_AUDIT_DATA_IPC; 6224 ad.u.ipc_id = sma->key; 6225 6226 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6227 SEM__ASSOCIATE, &ad); 6228 } 6229 6230 /* Note, at this point, sma is locked down */ 6231 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6232 { 6233 int err; 6234 u32 perms; 6235 6236 switch (cmd) { 6237 case IPC_INFO: 6238 case SEM_INFO: 6239 /* No specific object, just general system-wide information. */ 6240 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6241 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6242 case GETPID: 6243 case GETNCNT: 6244 case GETZCNT: 6245 perms = SEM__GETATTR; 6246 break; 6247 case GETVAL: 6248 case GETALL: 6249 perms = SEM__READ; 6250 break; 6251 case SETVAL: 6252 case SETALL: 6253 perms = SEM__WRITE; 6254 break; 6255 case IPC_RMID: 6256 perms = SEM__DESTROY; 6257 break; 6258 case IPC_SET: 6259 perms = SEM__SETATTR; 6260 break; 6261 case IPC_STAT: 6262 case SEM_STAT: 6263 case SEM_STAT_ANY: 6264 perms = SEM__GETATTR | SEM__ASSOCIATE; 6265 break; 6266 default: 6267 return 0; 6268 } 6269 6270 err = ipc_has_perm(sma, perms); 6271 return err; 6272 } 6273 6274 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6275 struct sembuf *sops, unsigned nsops, int alter) 6276 { 6277 u32 perms; 6278 6279 if (alter) 6280 perms = SEM__READ | SEM__WRITE; 6281 else 6282 perms = SEM__READ; 6283 6284 return ipc_has_perm(sma, perms); 6285 } 6286 6287 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6288 { 6289 u32 av = 0; 6290 6291 av = 0; 6292 if (flag & S_IRUGO) 6293 av |= IPC__UNIX_READ; 6294 if (flag & S_IWUGO) 6295 av |= IPC__UNIX_WRITE; 6296 6297 if (av == 0) 6298 return 0; 6299 6300 return ipc_has_perm(ipcp, av); 6301 } 6302 6303 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6304 { 6305 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6306 *secid = isec->sid; 6307 } 6308 6309 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6310 { 6311 if (inode) 6312 inode_doinit_with_dentry(inode, dentry); 6313 } 6314 6315 static int selinux_getprocattr(struct task_struct *p, 6316 const char *name, char **value) 6317 { 6318 const struct task_security_struct *__tsec; 6319 u32 sid; 6320 int error; 6321 unsigned len; 6322 6323 rcu_read_lock(); 6324 __tsec = selinux_cred(__task_cred(p)); 6325 6326 if (current != p) { 6327 error = avc_has_perm(current_sid(), __tsec->sid, 6328 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6329 if (error) 6330 goto bad; 6331 } 6332 6333 if (!strcmp(name, "current")) 6334 sid = __tsec->sid; 6335 else if (!strcmp(name, "prev")) 6336 sid = __tsec->osid; 6337 else if (!strcmp(name, "exec")) 6338 sid = __tsec->exec_sid; 6339 else if (!strcmp(name, "fscreate")) 6340 sid = __tsec->create_sid; 6341 else if (!strcmp(name, "keycreate")) 6342 sid = __tsec->keycreate_sid; 6343 else if (!strcmp(name, "sockcreate")) 6344 sid = __tsec->sockcreate_sid; 6345 else { 6346 error = -EINVAL; 6347 goto bad; 6348 } 6349 rcu_read_unlock(); 6350 6351 if (!sid) 6352 return 0; 6353 6354 error = security_sid_to_context(sid, value, &len); 6355 if (error) 6356 return error; 6357 return len; 6358 6359 bad: 6360 rcu_read_unlock(); 6361 return error; 6362 } 6363 6364 static int selinux_setprocattr(const char *name, void *value, size_t size) 6365 { 6366 struct task_security_struct *tsec; 6367 struct cred *new; 6368 u32 mysid = current_sid(), sid = 0, ptsid; 6369 int error; 6370 char *str = value; 6371 6372 /* 6373 * Basic control over ability to set these attributes at all. 6374 */ 6375 if (!strcmp(name, "exec")) 6376 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6377 PROCESS__SETEXEC, NULL); 6378 else if (!strcmp(name, "fscreate")) 6379 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6380 PROCESS__SETFSCREATE, NULL); 6381 else if (!strcmp(name, "keycreate")) 6382 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6383 PROCESS__SETKEYCREATE, NULL); 6384 else if (!strcmp(name, "sockcreate")) 6385 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6386 PROCESS__SETSOCKCREATE, NULL); 6387 else if (!strcmp(name, "current")) 6388 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6389 PROCESS__SETCURRENT, NULL); 6390 else 6391 error = -EINVAL; 6392 if (error) 6393 return error; 6394 6395 /* Obtain a SID for the context, if one was specified. */ 6396 if (size && str[0] && str[0] != '\n') { 6397 if (str[size-1] == '\n') { 6398 str[size-1] = 0; 6399 size--; 6400 } 6401 error = security_context_to_sid(value, size, 6402 &sid, GFP_KERNEL); 6403 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6404 if (!has_cap_mac_admin(true)) { 6405 struct audit_buffer *ab; 6406 size_t audit_size; 6407 6408 /* We strip a nul only if it is at the end, otherwise the 6409 * context contains a nul and we should audit that */ 6410 if (str[size - 1] == '\0') 6411 audit_size = size - 1; 6412 else 6413 audit_size = size; 6414 ab = audit_log_start(audit_context(), 6415 GFP_ATOMIC, 6416 AUDIT_SELINUX_ERR); 6417 if (!ab) 6418 return error; 6419 audit_log_format(ab, "op=fscreate invalid_context="); 6420 audit_log_n_untrustedstring(ab, value, audit_size); 6421 audit_log_end(ab); 6422 6423 return error; 6424 } 6425 error = security_context_to_sid_force(value, size, 6426 &sid); 6427 } 6428 if (error) 6429 return error; 6430 } 6431 6432 new = prepare_creds(); 6433 if (!new) 6434 return -ENOMEM; 6435 6436 /* Permission checking based on the specified context is 6437 performed during the actual operation (execve, 6438 open/mkdir/...), when we know the full context of the 6439 operation. See selinux_bprm_creds_for_exec for the execve 6440 checks and may_create for the file creation checks. The 6441 operation will then fail if the context is not permitted. */ 6442 tsec = selinux_cred(new); 6443 if (!strcmp(name, "exec")) { 6444 tsec->exec_sid = sid; 6445 } else if (!strcmp(name, "fscreate")) { 6446 tsec->create_sid = sid; 6447 } else if (!strcmp(name, "keycreate")) { 6448 if (sid) { 6449 error = avc_has_perm(mysid, sid, 6450 SECCLASS_KEY, KEY__CREATE, NULL); 6451 if (error) 6452 goto abort_change; 6453 } 6454 tsec->keycreate_sid = sid; 6455 } else if (!strcmp(name, "sockcreate")) { 6456 tsec->sockcreate_sid = sid; 6457 } else if (!strcmp(name, "current")) { 6458 error = -EINVAL; 6459 if (sid == 0) 6460 goto abort_change; 6461 6462 /* Only allow single threaded processes to change context */ 6463 if (!current_is_single_threaded()) { 6464 error = security_bounded_transition(tsec->sid, sid); 6465 if (error) 6466 goto abort_change; 6467 } 6468 6469 /* Check permissions for the transition. */ 6470 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6471 PROCESS__DYNTRANSITION, NULL); 6472 if (error) 6473 goto abort_change; 6474 6475 /* Check for ptracing, and update the task SID if ok. 6476 Otherwise, leave SID unchanged and fail. */ 6477 ptsid = ptrace_parent_sid(); 6478 if (ptsid != 0) { 6479 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6480 PROCESS__PTRACE, NULL); 6481 if (error) 6482 goto abort_change; 6483 } 6484 6485 tsec->sid = sid; 6486 } else { 6487 error = -EINVAL; 6488 goto abort_change; 6489 } 6490 6491 commit_creds(new); 6492 return size; 6493 6494 abort_change: 6495 abort_creds(new); 6496 return error; 6497 } 6498 6499 static int selinux_ismaclabel(const char *name) 6500 { 6501 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6502 } 6503 6504 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6505 { 6506 return security_sid_to_context(secid, 6507 secdata, seclen); 6508 } 6509 6510 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6511 { 6512 return security_context_to_sid(secdata, seclen, 6513 secid, GFP_KERNEL); 6514 } 6515 6516 static void selinux_release_secctx(char *secdata, u32 seclen) 6517 { 6518 kfree(secdata); 6519 } 6520 6521 static void selinux_inode_invalidate_secctx(struct inode *inode) 6522 { 6523 struct inode_security_struct *isec = selinux_inode(inode); 6524 6525 spin_lock(&isec->lock); 6526 isec->initialized = LABEL_INVALID; 6527 spin_unlock(&isec->lock); 6528 } 6529 6530 /* 6531 * called with inode->i_mutex locked 6532 */ 6533 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6534 { 6535 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6536 ctx, ctxlen, 0); 6537 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6538 return rc == -EOPNOTSUPP ? 0 : rc; 6539 } 6540 6541 /* 6542 * called with inode->i_mutex locked 6543 */ 6544 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6545 { 6546 return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6547 ctx, ctxlen, 0); 6548 } 6549 6550 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6551 { 6552 int len = 0; 6553 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6554 XATTR_SELINUX_SUFFIX, ctx, true); 6555 if (len < 0) 6556 return len; 6557 *ctxlen = len; 6558 return 0; 6559 } 6560 #ifdef CONFIG_KEYS 6561 6562 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6563 unsigned long flags) 6564 { 6565 const struct task_security_struct *tsec; 6566 struct key_security_struct *ksec; 6567 6568 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6569 if (!ksec) 6570 return -ENOMEM; 6571 6572 tsec = selinux_cred(cred); 6573 if (tsec->keycreate_sid) 6574 ksec->sid = tsec->keycreate_sid; 6575 else 6576 ksec->sid = tsec->sid; 6577 6578 k->security = ksec; 6579 return 0; 6580 } 6581 6582 static void selinux_key_free(struct key *k) 6583 { 6584 struct key_security_struct *ksec = k->security; 6585 6586 k->security = NULL; 6587 kfree(ksec); 6588 } 6589 6590 static int selinux_key_permission(key_ref_t key_ref, 6591 const struct cred *cred, 6592 enum key_need_perm need_perm) 6593 { 6594 struct key *key; 6595 struct key_security_struct *ksec; 6596 u32 perm, sid; 6597 6598 switch (need_perm) { 6599 case KEY_NEED_VIEW: 6600 perm = KEY__VIEW; 6601 break; 6602 case KEY_NEED_READ: 6603 perm = KEY__READ; 6604 break; 6605 case KEY_NEED_WRITE: 6606 perm = KEY__WRITE; 6607 break; 6608 case KEY_NEED_SEARCH: 6609 perm = KEY__SEARCH; 6610 break; 6611 case KEY_NEED_LINK: 6612 perm = KEY__LINK; 6613 break; 6614 case KEY_NEED_SETATTR: 6615 perm = KEY__SETATTR; 6616 break; 6617 case KEY_NEED_UNLINK: 6618 case KEY_SYSADMIN_OVERRIDE: 6619 case KEY_AUTHTOKEN_OVERRIDE: 6620 case KEY_DEFER_PERM_CHECK: 6621 return 0; 6622 default: 6623 WARN_ON(1); 6624 return -EPERM; 6625 6626 } 6627 6628 sid = cred_sid(cred); 6629 key = key_ref_to_ptr(key_ref); 6630 ksec = key->security; 6631 6632 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6633 } 6634 6635 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6636 { 6637 struct key_security_struct *ksec = key->security; 6638 char *context = NULL; 6639 unsigned len; 6640 int rc; 6641 6642 rc = security_sid_to_context(ksec->sid, 6643 &context, &len); 6644 if (!rc) 6645 rc = len; 6646 *_buffer = context; 6647 return rc; 6648 } 6649 6650 #ifdef CONFIG_KEY_NOTIFICATIONS 6651 static int selinux_watch_key(struct key *key) 6652 { 6653 struct key_security_struct *ksec = key->security; 6654 u32 sid = current_sid(); 6655 6656 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6657 } 6658 #endif 6659 #endif 6660 6661 #ifdef CONFIG_SECURITY_INFINIBAND 6662 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6663 { 6664 struct common_audit_data ad; 6665 int err; 6666 u32 sid = 0; 6667 struct ib_security_struct *sec = ib_sec; 6668 struct lsm_ibpkey_audit ibpkey; 6669 6670 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6671 if (err) 6672 return err; 6673 6674 ad.type = LSM_AUDIT_DATA_IBPKEY; 6675 ibpkey.subnet_prefix = subnet_prefix; 6676 ibpkey.pkey = pkey_val; 6677 ad.u.ibpkey = &ibpkey; 6678 return avc_has_perm(sec->sid, sid, 6679 SECCLASS_INFINIBAND_PKEY, 6680 INFINIBAND_PKEY__ACCESS, &ad); 6681 } 6682 6683 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6684 u8 port_num) 6685 { 6686 struct common_audit_data ad; 6687 int err; 6688 u32 sid = 0; 6689 struct ib_security_struct *sec = ib_sec; 6690 struct lsm_ibendport_audit ibendport; 6691 6692 err = security_ib_endport_sid(dev_name, port_num, 6693 &sid); 6694 6695 if (err) 6696 return err; 6697 6698 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6699 ibendport.dev_name = dev_name; 6700 ibendport.port = port_num; 6701 ad.u.ibendport = &ibendport; 6702 return avc_has_perm(sec->sid, sid, 6703 SECCLASS_INFINIBAND_ENDPORT, 6704 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6705 } 6706 6707 static int selinux_ib_alloc_security(void **ib_sec) 6708 { 6709 struct ib_security_struct *sec; 6710 6711 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6712 if (!sec) 6713 return -ENOMEM; 6714 sec->sid = current_sid(); 6715 6716 *ib_sec = sec; 6717 return 0; 6718 } 6719 6720 static void selinux_ib_free_security(void *ib_sec) 6721 { 6722 kfree(ib_sec); 6723 } 6724 #endif 6725 6726 #ifdef CONFIG_BPF_SYSCALL 6727 static int selinux_bpf(int cmd, union bpf_attr *attr, 6728 unsigned int size) 6729 { 6730 u32 sid = current_sid(); 6731 int ret; 6732 6733 switch (cmd) { 6734 case BPF_MAP_CREATE: 6735 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6736 NULL); 6737 break; 6738 case BPF_PROG_LOAD: 6739 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6740 NULL); 6741 break; 6742 default: 6743 ret = 0; 6744 break; 6745 } 6746 6747 return ret; 6748 } 6749 6750 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6751 { 6752 u32 av = 0; 6753 6754 if (fmode & FMODE_READ) 6755 av |= BPF__MAP_READ; 6756 if (fmode & FMODE_WRITE) 6757 av |= BPF__MAP_WRITE; 6758 return av; 6759 } 6760 6761 /* This function will check the file pass through unix socket or binder to see 6762 * if it is a bpf related object. And apply corresponding checks on the bpf 6763 * object based on the type. The bpf maps and programs, not like other files and 6764 * socket, are using a shared anonymous inode inside the kernel as their inode. 6765 * So checking that inode cannot identify if the process have privilege to 6766 * access the bpf object and that's why we have to add this additional check in 6767 * selinux_file_receive and selinux_binder_transfer_files. 6768 */ 6769 static int bpf_fd_pass(const struct file *file, u32 sid) 6770 { 6771 struct bpf_security_struct *bpfsec; 6772 struct bpf_prog *prog; 6773 struct bpf_map *map; 6774 int ret; 6775 6776 if (file->f_op == &bpf_map_fops) { 6777 map = file->private_data; 6778 bpfsec = map->security; 6779 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6780 bpf_map_fmode_to_av(file->f_mode), NULL); 6781 if (ret) 6782 return ret; 6783 } else if (file->f_op == &bpf_prog_fops) { 6784 prog = file->private_data; 6785 bpfsec = prog->aux->security; 6786 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6787 BPF__PROG_RUN, NULL); 6788 if (ret) 6789 return ret; 6790 } 6791 return 0; 6792 } 6793 6794 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6795 { 6796 u32 sid = current_sid(); 6797 struct bpf_security_struct *bpfsec; 6798 6799 bpfsec = map->security; 6800 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6801 bpf_map_fmode_to_av(fmode), NULL); 6802 } 6803 6804 static int selinux_bpf_prog(struct bpf_prog *prog) 6805 { 6806 u32 sid = current_sid(); 6807 struct bpf_security_struct *bpfsec; 6808 6809 bpfsec = prog->aux->security; 6810 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6811 BPF__PROG_RUN, NULL); 6812 } 6813 6814 static int selinux_bpf_map_alloc(struct bpf_map *map) 6815 { 6816 struct bpf_security_struct *bpfsec; 6817 6818 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6819 if (!bpfsec) 6820 return -ENOMEM; 6821 6822 bpfsec->sid = current_sid(); 6823 map->security = bpfsec; 6824 6825 return 0; 6826 } 6827 6828 static void selinux_bpf_map_free(struct bpf_map *map) 6829 { 6830 struct bpf_security_struct *bpfsec = map->security; 6831 6832 map->security = NULL; 6833 kfree(bpfsec); 6834 } 6835 6836 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6837 { 6838 struct bpf_security_struct *bpfsec; 6839 6840 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6841 if (!bpfsec) 6842 return -ENOMEM; 6843 6844 bpfsec->sid = current_sid(); 6845 aux->security = bpfsec; 6846 6847 return 0; 6848 } 6849 6850 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6851 { 6852 struct bpf_security_struct *bpfsec = aux->security; 6853 6854 aux->security = NULL; 6855 kfree(bpfsec); 6856 } 6857 #endif 6858 6859 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 6860 .lbs_cred = sizeof(struct task_security_struct), 6861 .lbs_file = sizeof(struct file_security_struct), 6862 .lbs_inode = sizeof(struct inode_security_struct), 6863 .lbs_ipc = sizeof(struct ipc_security_struct), 6864 .lbs_msg_msg = sizeof(struct msg_security_struct), 6865 .lbs_superblock = sizeof(struct superblock_security_struct), 6866 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 6867 }; 6868 6869 #ifdef CONFIG_PERF_EVENTS 6870 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6871 { 6872 u32 requested, sid = current_sid(); 6873 6874 if (type == PERF_SECURITY_OPEN) 6875 requested = PERF_EVENT__OPEN; 6876 else if (type == PERF_SECURITY_CPU) 6877 requested = PERF_EVENT__CPU; 6878 else if (type == PERF_SECURITY_KERNEL) 6879 requested = PERF_EVENT__KERNEL; 6880 else if (type == PERF_SECURITY_TRACEPOINT) 6881 requested = PERF_EVENT__TRACEPOINT; 6882 else 6883 return -EINVAL; 6884 6885 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 6886 requested, NULL); 6887 } 6888 6889 static int selinux_perf_event_alloc(struct perf_event *event) 6890 { 6891 struct perf_event_security_struct *perfsec; 6892 6893 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6894 if (!perfsec) 6895 return -ENOMEM; 6896 6897 perfsec->sid = current_sid(); 6898 event->security = perfsec; 6899 6900 return 0; 6901 } 6902 6903 static void selinux_perf_event_free(struct perf_event *event) 6904 { 6905 struct perf_event_security_struct *perfsec = event->security; 6906 6907 event->security = NULL; 6908 kfree(perfsec); 6909 } 6910 6911 static int selinux_perf_event_read(struct perf_event *event) 6912 { 6913 struct perf_event_security_struct *perfsec = event->security; 6914 u32 sid = current_sid(); 6915 6916 return avc_has_perm(sid, perfsec->sid, 6917 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6918 } 6919 6920 static int selinux_perf_event_write(struct perf_event *event) 6921 { 6922 struct perf_event_security_struct *perfsec = event->security; 6923 u32 sid = current_sid(); 6924 6925 return avc_has_perm(sid, perfsec->sid, 6926 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6927 } 6928 #endif 6929 6930 #ifdef CONFIG_IO_URING 6931 /** 6932 * selinux_uring_override_creds - check the requested cred override 6933 * @new: the target creds 6934 * 6935 * Check to see if the current task is allowed to override it's credentials 6936 * to service an io_uring operation. 6937 */ 6938 static int selinux_uring_override_creds(const struct cred *new) 6939 { 6940 return avc_has_perm(current_sid(), cred_sid(new), 6941 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 6942 } 6943 6944 /** 6945 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 6946 * 6947 * Check to see if the current task is allowed to create a new io_uring 6948 * kernel polling thread. 6949 */ 6950 static int selinux_uring_sqpoll(void) 6951 { 6952 u32 sid = current_sid(); 6953 6954 return avc_has_perm(sid, sid, 6955 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 6956 } 6957 6958 /** 6959 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 6960 * @ioucmd: the io_uring command structure 6961 * 6962 * Check to see if the current domain is allowed to execute an 6963 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 6964 * 6965 */ 6966 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 6967 { 6968 struct file *file = ioucmd->file; 6969 struct inode *inode = file_inode(file); 6970 struct inode_security_struct *isec = selinux_inode(inode); 6971 struct common_audit_data ad; 6972 6973 ad.type = LSM_AUDIT_DATA_FILE; 6974 ad.u.file = file; 6975 6976 return avc_has_perm(current_sid(), isec->sid, 6977 SECCLASS_IO_URING, IO_URING__CMD, &ad); 6978 } 6979 #endif /* CONFIG_IO_URING */ 6980 6981 /* 6982 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6983 * 1. any hooks that don't belong to (2.) or (3.) below, 6984 * 2. hooks that both access structures allocated by other hooks, and allocate 6985 * structures that can be later accessed by other hooks (mostly "cloning" 6986 * hooks), 6987 * 3. hooks that only allocate structures that can be later accessed by other 6988 * hooks ("allocating" hooks). 6989 * 6990 * Please follow block comment delimiters in the list to keep this order. 6991 */ 6992 static struct security_hook_list selinux_hooks[] __ro_after_init = { 6993 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6994 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6995 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6996 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6997 6998 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6999 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 7000 LSM_HOOK_INIT(capget, selinux_capget), 7001 LSM_HOOK_INIT(capset, selinux_capset), 7002 LSM_HOOK_INIT(capable, selinux_capable), 7003 LSM_HOOK_INIT(quotactl, selinux_quotactl), 7004 LSM_HOOK_INIT(quota_on, selinux_quota_on), 7005 LSM_HOOK_INIT(syslog, selinux_syslog), 7006 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 7007 7008 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 7009 7010 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 7011 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 7012 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 7013 7014 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 7015 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 7016 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 7017 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 7018 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 7019 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 7020 LSM_HOOK_INIT(sb_mount, selinux_mount), 7021 LSM_HOOK_INIT(sb_umount, selinux_umount), 7022 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7023 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7024 7025 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7026 7027 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7028 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7029 7030 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7031 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7032 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7033 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7034 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7035 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7036 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7037 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7038 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7039 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7040 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7041 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7042 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7043 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7044 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7045 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7046 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7047 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7048 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7049 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7050 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7051 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7052 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7053 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7054 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7055 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7056 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7057 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7058 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7059 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7060 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7061 7062 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7063 7064 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7065 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7066 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7067 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7068 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7069 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7070 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7071 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7072 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7073 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7074 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7075 7076 LSM_HOOK_INIT(file_open, selinux_file_open), 7077 7078 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7079 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7080 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7081 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7082 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7083 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7084 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7085 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7086 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7087 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7088 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7089 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7090 LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), 7091 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), 7092 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7093 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7094 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7095 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7096 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7097 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7098 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7099 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7100 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7101 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7102 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7103 7104 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7105 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7106 7107 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7108 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7109 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7110 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7111 7112 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7113 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7114 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7115 7116 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7117 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7118 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7119 7120 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7121 7122 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7123 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7124 7125 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7126 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7127 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7128 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7129 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7130 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7131 7132 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7133 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7134 7135 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7136 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7137 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7138 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7139 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7140 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7141 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7142 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7143 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7144 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7145 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7146 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7147 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7148 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7149 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7150 LSM_HOOK_INIT(socket_getpeersec_stream, 7151 selinux_socket_getpeersec_stream), 7152 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7153 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7154 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7155 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7156 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7157 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7158 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7159 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7160 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7161 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7162 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7163 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7164 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7165 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7166 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7167 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7168 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7169 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7170 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7171 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7172 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7173 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7174 #ifdef CONFIG_SECURITY_INFINIBAND 7175 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7176 LSM_HOOK_INIT(ib_endport_manage_subnet, 7177 selinux_ib_endport_manage_subnet), 7178 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7179 #endif 7180 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7181 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7182 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7183 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7184 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7185 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7186 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7187 selinux_xfrm_state_pol_flow_match), 7188 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7189 #endif 7190 7191 #ifdef CONFIG_KEYS 7192 LSM_HOOK_INIT(key_free, selinux_key_free), 7193 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7194 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7195 #ifdef CONFIG_KEY_NOTIFICATIONS 7196 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7197 #endif 7198 #endif 7199 7200 #ifdef CONFIG_AUDIT 7201 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7202 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7203 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7204 #endif 7205 7206 #ifdef CONFIG_BPF_SYSCALL 7207 LSM_HOOK_INIT(bpf, selinux_bpf), 7208 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7209 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7210 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7211 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7212 #endif 7213 7214 #ifdef CONFIG_PERF_EVENTS 7215 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7216 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7217 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7218 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7219 #endif 7220 7221 #ifdef CONFIG_IO_URING 7222 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7223 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7224 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7225 #endif 7226 7227 /* 7228 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7229 */ 7230 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7231 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7232 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7233 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7234 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7235 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7236 #endif 7237 7238 /* 7239 * PUT "ALLOCATING" HOOKS HERE 7240 */ 7241 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7242 LSM_HOOK_INIT(msg_queue_alloc_security, 7243 selinux_msg_queue_alloc_security), 7244 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7245 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7246 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7247 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7248 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7249 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7250 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7251 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7252 #ifdef CONFIG_SECURITY_INFINIBAND 7253 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7254 #endif 7255 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7256 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7257 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7258 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7259 selinux_xfrm_state_alloc_acquire), 7260 #endif 7261 #ifdef CONFIG_KEYS 7262 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7263 #endif 7264 #ifdef CONFIG_AUDIT 7265 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7266 #endif 7267 #ifdef CONFIG_BPF_SYSCALL 7268 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7269 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7270 #endif 7271 #ifdef CONFIG_PERF_EVENTS 7272 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7273 #endif 7274 }; 7275 7276 static __init int selinux_init(void) 7277 { 7278 pr_info("SELinux: Initializing.\n"); 7279 7280 memset(&selinux_state, 0, sizeof(selinux_state)); 7281 enforcing_set(selinux_enforcing_boot); 7282 selinux_avc_init(); 7283 mutex_init(&selinux_state.status_lock); 7284 mutex_init(&selinux_state.policy_mutex); 7285 7286 /* Set the security state for the initial task. */ 7287 cred_init_security(); 7288 7289 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7290 if (!default_noexec) 7291 pr_notice("SELinux: virtual memory is executable by default\n"); 7292 7293 avc_init(); 7294 7295 avtab_cache_init(); 7296 7297 ebitmap_cache_init(); 7298 7299 hashtab_cache_init(); 7300 7301 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7302 7303 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7304 panic("SELinux: Unable to register AVC netcache callback\n"); 7305 7306 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7307 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7308 7309 if (selinux_enforcing_boot) 7310 pr_debug("SELinux: Starting in enforcing mode\n"); 7311 else 7312 pr_debug("SELinux: Starting in permissive mode\n"); 7313 7314 fs_validate_description("selinux", selinux_fs_parameters); 7315 7316 return 0; 7317 } 7318 7319 static void delayed_superblock_init(struct super_block *sb, void *unused) 7320 { 7321 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7322 } 7323 7324 void selinux_complete_init(void) 7325 { 7326 pr_debug("SELinux: Completing initialization.\n"); 7327 7328 /* Set up any superblocks initialized prior to the policy load. */ 7329 pr_debug("SELinux: Setting up existing superblocks.\n"); 7330 iterate_supers(delayed_superblock_init, NULL); 7331 } 7332 7333 /* SELinux requires early initialization in order to label 7334 all processes and objects when they are created. */ 7335 DEFINE_LSM(selinux) = { 7336 .name = "selinux", 7337 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7338 .enabled = &selinux_enabled_boot, 7339 .blobs = &selinux_blob_sizes, 7340 .init = selinux_init, 7341 }; 7342 7343 #if defined(CONFIG_NETFILTER) 7344 static const struct nf_hook_ops selinux_nf_ops[] = { 7345 { 7346 .hook = selinux_ip_postroute, 7347 .pf = NFPROTO_IPV4, 7348 .hooknum = NF_INET_POST_ROUTING, 7349 .priority = NF_IP_PRI_SELINUX_LAST, 7350 }, 7351 { 7352 .hook = selinux_ip_forward, 7353 .pf = NFPROTO_IPV4, 7354 .hooknum = NF_INET_FORWARD, 7355 .priority = NF_IP_PRI_SELINUX_FIRST, 7356 }, 7357 { 7358 .hook = selinux_ip_output, 7359 .pf = NFPROTO_IPV4, 7360 .hooknum = NF_INET_LOCAL_OUT, 7361 .priority = NF_IP_PRI_SELINUX_FIRST, 7362 }, 7363 #if IS_ENABLED(CONFIG_IPV6) 7364 { 7365 .hook = selinux_ip_postroute, 7366 .pf = NFPROTO_IPV6, 7367 .hooknum = NF_INET_POST_ROUTING, 7368 .priority = NF_IP6_PRI_SELINUX_LAST, 7369 }, 7370 { 7371 .hook = selinux_ip_forward, 7372 .pf = NFPROTO_IPV6, 7373 .hooknum = NF_INET_FORWARD, 7374 .priority = NF_IP6_PRI_SELINUX_FIRST, 7375 }, 7376 { 7377 .hook = selinux_ip_output, 7378 .pf = NFPROTO_IPV6, 7379 .hooknum = NF_INET_LOCAL_OUT, 7380 .priority = NF_IP6_PRI_SELINUX_FIRST, 7381 }, 7382 #endif /* IPV6 */ 7383 }; 7384 7385 static int __net_init selinux_nf_register(struct net *net) 7386 { 7387 return nf_register_net_hooks(net, selinux_nf_ops, 7388 ARRAY_SIZE(selinux_nf_ops)); 7389 } 7390 7391 static void __net_exit selinux_nf_unregister(struct net *net) 7392 { 7393 nf_unregister_net_hooks(net, selinux_nf_ops, 7394 ARRAY_SIZE(selinux_nf_ops)); 7395 } 7396 7397 static struct pernet_operations selinux_net_ops = { 7398 .init = selinux_nf_register, 7399 .exit = selinux_nf_unregister, 7400 }; 7401 7402 static int __init selinux_nf_ip_init(void) 7403 { 7404 int err; 7405 7406 if (!selinux_enabled_boot) 7407 return 0; 7408 7409 pr_debug("SELinux: Registering netfilter hooks\n"); 7410 7411 err = register_pernet_subsys(&selinux_net_ops); 7412 if (err) 7413 panic("SELinux: register_pernet_subsys: error %d\n", err); 7414 7415 return 0; 7416 } 7417 __initcall(selinux_nf_ip_init); 7418 #endif /* CONFIG_NETFILTER */ 7419