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 #include <uapi/linux/lsm.h> 96 97 #include "avc.h" 98 #include "objsec.h" 99 #include "netif.h" 100 #include "netnode.h" 101 #include "netport.h" 102 #include "ibpkey.h" 103 #include "xfrm.h" 104 #include "netlabel.h" 105 #include "audit.h" 106 #include "avc_ss.h" 107 108 #define SELINUX_INODE_INIT_XATTRS 1 109 110 struct selinux_state selinux_state; 111 112 /* SECMARK reference count */ 113 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 114 115 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 116 static int selinux_enforcing_boot __initdata; 117 118 static int __init enforcing_setup(char *str) 119 { 120 unsigned long enforcing; 121 if (!kstrtoul(str, 0, &enforcing)) 122 selinux_enforcing_boot = enforcing ? 1 : 0; 123 return 1; 124 } 125 __setup("enforcing=", enforcing_setup); 126 #else 127 #define selinux_enforcing_boot 1 128 #endif 129 130 int selinux_enabled_boot __initdata = 1; 131 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 132 static int __init selinux_enabled_setup(char *str) 133 { 134 unsigned long enabled; 135 if (!kstrtoul(str, 0, &enabled)) 136 selinux_enabled_boot = enabled ? 1 : 0; 137 return 1; 138 } 139 __setup("selinux=", selinux_enabled_setup); 140 #endif 141 142 static int __init checkreqprot_setup(char *str) 143 { 144 unsigned long checkreqprot; 145 146 if (!kstrtoul(str, 0, &checkreqprot)) { 147 if (checkreqprot) 148 pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n"); 149 } 150 return 1; 151 } 152 __setup("checkreqprot=", checkreqprot_setup); 153 154 /** 155 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 156 * 157 * Description: 158 * This function checks the SECMARK reference counter to see if any SECMARK 159 * targets are currently configured, if the reference counter is greater than 160 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 161 * enabled, false (0) if SECMARK is disabled. If the always_check_network 162 * policy capability is enabled, SECMARK is always considered enabled. 163 * 164 */ 165 static int selinux_secmark_enabled(void) 166 { 167 return (selinux_policycap_alwaysnetwork() || 168 atomic_read(&selinux_secmark_refcount)); 169 } 170 171 /** 172 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 173 * 174 * Description: 175 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 176 * (1) if any are enabled or false (0) if neither are enabled. If the 177 * always_check_network policy capability is enabled, peer labeling 178 * is always considered enabled. 179 * 180 */ 181 static int selinux_peerlbl_enabled(void) 182 { 183 return (selinux_policycap_alwaysnetwork() || 184 netlbl_enabled() || selinux_xfrm_enabled()); 185 } 186 187 static int selinux_netcache_avc_callback(u32 event) 188 { 189 if (event == AVC_CALLBACK_RESET) { 190 sel_netif_flush(); 191 sel_netnode_flush(); 192 sel_netport_flush(); 193 synchronize_net(); 194 } 195 return 0; 196 } 197 198 static int selinux_lsm_notifier_avc_callback(u32 event) 199 { 200 if (event == AVC_CALLBACK_RESET) { 201 sel_ib_pkey_flush(); 202 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 203 } 204 205 return 0; 206 } 207 208 /* 209 * initialise the security for the init task 210 */ 211 static void cred_init_security(void) 212 { 213 struct task_security_struct *tsec; 214 215 tsec = selinux_cred(unrcu_pointer(current->real_cred)); 216 tsec->osid = tsec->sid = SECINITSID_KERNEL; 217 } 218 219 /* 220 * get the security ID of a set of credentials 221 */ 222 static inline u32 cred_sid(const struct cred *cred) 223 { 224 const struct task_security_struct *tsec; 225 226 tsec = selinux_cred(cred); 227 return tsec->sid; 228 } 229 230 static void __ad_net_init(struct common_audit_data *ad, 231 struct lsm_network_audit *net, 232 int ifindex, struct sock *sk, u16 family) 233 { 234 ad->type = LSM_AUDIT_DATA_NET; 235 ad->u.net = net; 236 net->netif = ifindex; 237 net->sk = sk; 238 net->family = family; 239 } 240 241 static void ad_net_init_from_sk(struct common_audit_data *ad, 242 struct lsm_network_audit *net, 243 struct sock *sk) 244 { 245 __ad_net_init(ad, net, 0, sk, 0); 246 } 247 248 static void ad_net_init_from_iif(struct common_audit_data *ad, 249 struct lsm_network_audit *net, 250 int ifindex, u16 family) 251 { 252 __ad_net_init(ad, net, ifindex, NULL, family); 253 } 254 255 /* 256 * get the objective security ID of a task 257 */ 258 static inline u32 task_sid_obj(const struct task_struct *task) 259 { 260 u32 sid; 261 262 rcu_read_lock(); 263 sid = cred_sid(__task_cred(task)); 264 rcu_read_unlock(); 265 return sid; 266 } 267 268 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 269 270 /* 271 * Try reloading inode security labels that have been marked as invalid. The 272 * @may_sleep parameter indicates when sleeping and thus reloading labels is 273 * allowed; when set to false, returns -ECHILD when the label is 274 * invalid. The @dentry parameter should be set to a dentry of the inode. 275 */ 276 static int __inode_security_revalidate(struct inode *inode, 277 struct dentry *dentry, 278 bool may_sleep) 279 { 280 struct inode_security_struct *isec = selinux_inode(inode); 281 282 might_sleep_if(may_sleep); 283 284 if (selinux_initialized() && 285 isec->initialized != LABEL_INITIALIZED) { 286 if (!may_sleep) 287 return -ECHILD; 288 289 /* 290 * Try reloading the inode security label. This will fail if 291 * @opt_dentry is NULL and no dentry for this inode can be 292 * found; in that case, continue using the old label. 293 */ 294 inode_doinit_with_dentry(inode, dentry); 295 } 296 return 0; 297 } 298 299 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 300 { 301 return selinux_inode(inode); 302 } 303 304 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 305 { 306 int error; 307 308 error = __inode_security_revalidate(inode, NULL, !rcu); 309 if (error) 310 return ERR_PTR(error); 311 return selinux_inode(inode); 312 } 313 314 /* 315 * Get the security label of an inode. 316 */ 317 static struct inode_security_struct *inode_security(struct inode *inode) 318 { 319 __inode_security_revalidate(inode, NULL, true); 320 return selinux_inode(inode); 321 } 322 323 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 324 { 325 struct inode *inode = d_backing_inode(dentry); 326 327 return selinux_inode(inode); 328 } 329 330 /* 331 * Get the security label of a dentry's backing inode. 332 */ 333 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 334 { 335 struct inode *inode = d_backing_inode(dentry); 336 337 __inode_security_revalidate(inode, dentry, true); 338 return selinux_inode(inode); 339 } 340 341 static void inode_free_security(struct inode *inode) 342 { 343 struct inode_security_struct *isec = selinux_inode(inode); 344 struct superblock_security_struct *sbsec; 345 346 if (!isec) 347 return; 348 sbsec = selinux_superblock(inode->i_sb); 349 /* 350 * As not all inode security structures are in a list, we check for 351 * empty list outside of the lock to make sure that we won't waste 352 * time taking a lock doing nothing. 353 * 354 * The list_del_init() function can be safely called more than once. 355 * It should not be possible for this function to be called with 356 * concurrent list_add(), but for better safety against future changes 357 * in the code, we use list_empty_careful() here. 358 */ 359 if (!list_empty_careful(&isec->list)) { 360 spin_lock(&sbsec->isec_lock); 361 list_del_init(&isec->list); 362 spin_unlock(&sbsec->isec_lock); 363 } 364 } 365 366 struct selinux_mnt_opts { 367 u32 fscontext_sid; 368 u32 context_sid; 369 u32 rootcontext_sid; 370 u32 defcontext_sid; 371 }; 372 373 static void selinux_free_mnt_opts(void *mnt_opts) 374 { 375 kfree(mnt_opts); 376 } 377 378 enum { 379 Opt_error = -1, 380 Opt_context = 0, 381 Opt_defcontext = 1, 382 Opt_fscontext = 2, 383 Opt_rootcontext = 3, 384 Opt_seclabel = 4, 385 }; 386 387 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 388 static const struct { 389 const char *name; 390 int len; 391 int opt; 392 bool has_arg; 393 } tokens[] = { 394 A(context, true), 395 A(fscontext, true), 396 A(defcontext, true), 397 A(rootcontext, true), 398 A(seclabel, false), 399 }; 400 #undef A 401 402 static int match_opt_prefix(char *s, int l, char **arg) 403 { 404 int i; 405 406 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 407 size_t len = tokens[i].len; 408 if (len > l || memcmp(s, tokens[i].name, len)) 409 continue; 410 if (tokens[i].has_arg) { 411 if (len == l || s[len] != '=') 412 continue; 413 *arg = s + len + 1; 414 } else if (len != l) 415 continue; 416 return tokens[i].opt; 417 } 418 return Opt_error; 419 } 420 421 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 422 423 static int may_context_mount_sb_relabel(u32 sid, 424 struct superblock_security_struct *sbsec, 425 const struct cred *cred) 426 { 427 const struct task_security_struct *tsec = selinux_cred(cred); 428 int rc; 429 430 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 431 FILESYSTEM__RELABELFROM, NULL); 432 if (rc) 433 return rc; 434 435 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 436 FILESYSTEM__RELABELTO, NULL); 437 return rc; 438 } 439 440 static int may_context_mount_inode_relabel(u32 sid, 441 struct superblock_security_struct *sbsec, 442 const struct cred *cred) 443 { 444 const struct task_security_struct *tsec = selinux_cred(cred); 445 int rc; 446 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 447 FILESYSTEM__RELABELFROM, NULL); 448 if (rc) 449 return rc; 450 451 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 452 FILESYSTEM__ASSOCIATE, NULL); 453 return rc; 454 } 455 456 static int selinux_is_genfs_special_handling(struct super_block *sb) 457 { 458 /* Special handling. Genfs but also in-core setxattr handler */ 459 return !strcmp(sb->s_type->name, "sysfs") || 460 !strcmp(sb->s_type->name, "pstore") || 461 !strcmp(sb->s_type->name, "debugfs") || 462 !strcmp(sb->s_type->name, "tracefs") || 463 !strcmp(sb->s_type->name, "rootfs") || 464 (selinux_policycap_cgroupseclabel() && 465 (!strcmp(sb->s_type->name, "cgroup") || 466 !strcmp(sb->s_type->name, "cgroup2"))); 467 } 468 469 static int selinux_is_sblabel_mnt(struct super_block *sb) 470 { 471 struct superblock_security_struct *sbsec = selinux_superblock(sb); 472 473 /* 474 * IMPORTANT: Double-check logic in this function when adding a new 475 * SECURITY_FS_USE_* definition! 476 */ 477 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 478 479 switch (sbsec->behavior) { 480 case SECURITY_FS_USE_XATTR: 481 case SECURITY_FS_USE_TRANS: 482 case SECURITY_FS_USE_TASK: 483 case SECURITY_FS_USE_NATIVE: 484 return 1; 485 486 case SECURITY_FS_USE_GENFS: 487 return selinux_is_genfs_special_handling(sb); 488 489 /* Never allow relabeling on context mounts */ 490 case SECURITY_FS_USE_MNTPOINT: 491 case SECURITY_FS_USE_NONE: 492 default: 493 return 0; 494 } 495 } 496 497 static int sb_check_xattr_support(struct super_block *sb) 498 { 499 struct superblock_security_struct *sbsec = selinux_superblock(sb); 500 struct dentry *root = sb->s_root; 501 struct inode *root_inode = d_backing_inode(root); 502 u32 sid; 503 int rc; 504 505 /* 506 * Make sure that the xattr handler exists and that no 507 * error other than -ENODATA is returned by getxattr on 508 * the root directory. -ENODATA is ok, as this may be 509 * the first boot of the SELinux kernel before we have 510 * assigned xattr values to the filesystem. 511 */ 512 if (!(root_inode->i_opflags & IOP_XATTR)) { 513 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", 514 sb->s_id, sb->s_type->name); 515 goto fallback; 516 } 517 518 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 519 if (rc < 0 && rc != -ENODATA) { 520 if (rc == -EOPNOTSUPP) { 521 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", 522 sb->s_id, sb->s_type->name); 523 goto fallback; 524 } else { 525 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", 526 sb->s_id, sb->s_type->name, -rc); 527 return rc; 528 } 529 } 530 return 0; 531 532 fallback: 533 /* No xattr support - try to fallback to genfs if possible. */ 534 rc = security_genfs_sid(sb->s_type->name, "/", 535 SECCLASS_DIR, &sid); 536 if (rc) 537 return -EOPNOTSUPP; 538 539 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", 540 sb->s_id, sb->s_type->name); 541 sbsec->behavior = SECURITY_FS_USE_GENFS; 542 sbsec->sid = sid; 543 return 0; 544 } 545 546 static int sb_finish_set_opts(struct super_block *sb) 547 { 548 struct superblock_security_struct *sbsec = selinux_superblock(sb); 549 struct dentry *root = sb->s_root; 550 struct inode *root_inode = d_backing_inode(root); 551 int rc = 0; 552 553 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 554 rc = sb_check_xattr_support(sb); 555 if (rc) 556 return rc; 557 } 558 559 sbsec->flags |= SE_SBINITIALIZED; 560 561 /* 562 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 563 * leave the flag untouched because sb_clone_mnt_opts might be handing 564 * us a superblock that needs the flag to be cleared. 565 */ 566 if (selinux_is_sblabel_mnt(sb)) 567 sbsec->flags |= SBLABEL_MNT; 568 else 569 sbsec->flags &= ~SBLABEL_MNT; 570 571 /* Initialize the root inode. */ 572 rc = inode_doinit_with_dentry(root_inode, root); 573 574 /* Initialize any other inodes associated with the superblock, e.g. 575 inodes created prior to initial policy load or inodes created 576 during get_sb by a pseudo filesystem that directly 577 populates itself. */ 578 spin_lock(&sbsec->isec_lock); 579 while (!list_empty(&sbsec->isec_head)) { 580 struct inode_security_struct *isec = 581 list_first_entry(&sbsec->isec_head, 582 struct inode_security_struct, list); 583 struct inode *inode = isec->inode; 584 list_del_init(&isec->list); 585 spin_unlock(&sbsec->isec_lock); 586 inode = igrab(inode); 587 if (inode) { 588 if (!IS_PRIVATE(inode)) 589 inode_doinit_with_dentry(inode, NULL); 590 iput(inode); 591 } 592 spin_lock(&sbsec->isec_lock); 593 } 594 spin_unlock(&sbsec->isec_lock); 595 return rc; 596 } 597 598 static int bad_option(struct superblock_security_struct *sbsec, char flag, 599 u32 old_sid, u32 new_sid) 600 { 601 char mnt_flags = sbsec->flags & SE_MNTMASK; 602 603 /* check if the old mount command had the same options */ 604 if (sbsec->flags & SE_SBINITIALIZED) 605 if (!(sbsec->flags & flag) || 606 (old_sid != new_sid)) 607 return 1; 608 609 /* check if we were passed the same options twice, 610 * aka someone passed context=a,context=b 611 */ 612 if (!(sbsec->flags & SE_SBINITIALIZED)) 613 if (mnt_flags & flag) 614 return 1; 615 return 0; 616 } 617 618 /* 619 * Allow filesystems with binary mount data to explicitly set mount point 620 * labeling information. 621 */ 622 static int selinux_set_mnt_opts(struct super_block *sb, 623 void *mnt_opts, 624 unsigned long kern_flags, 625 unsigned long *set_kern_flags) 626 { 627 const struct cred *cred = current_cred(); 628 struct superblock_security_struct *sbsec = selinux_superblock(sb); 629 struct dentry *root = sb->s_root; 630 struct selinux_mnt_opts *opts = mnt_opts; 631 struct inode_security_struct *root_isec; 632 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 633 u32 defcontext_sid = 0; 634 int rc = 0; 635 636 /* 637 * Specifying internal flags without providing a place to 638 * place the results is not allowed 639 */ 640 if (kern_flags && !set_kern_flags) 641 return -EINVAL; 642 643 mutex_lock(&sbsec->lock); 644 645 if (!selinux_initialized()) { 646 if (!opts) { 647 /* Defer initialization until selinux_complete_init, 648 after the initial policy is loaded and the security 649 server is ready to handle calls. */ 650 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 651 sbsec->flags |= SE_SBNATIVE; 652 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 653 } 654 goto out; 655 } 656 rc = -EINVAL; 657 pr_warn("SELinux: Unable to set superblock options " 658 "before the security server is initialized\n"); 659 goto out; 660 } 661 662 /* 663 * Binary mount data FS will come through this function twice. Once 664 * from an explicit call and once from the generic calls from the vfs. 665 * Since the generic VFS calls will not contain any security mount data 666 * we need to skip the double mount verification. 667 * 668 * This does open a hole in which we will not notice if the first 669 * mount using this sb set explicit options and a second mount using 670 * this sb does not set any security options. (The first options 671 * will be used for both mounts) 672 */ 673 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 674 && !opts) 675 goto out; 676 677 root_isec = backing_inode_security_novalidate(root); 678 679 /* 680 * parse the mount options, check if they are valid sids. 681 * also check if someone is trying to mount the same sb more 682 * than once with different security options. 683 */ 684 if (opts) { 685 if (opts->fscontext_sid) { 686 fscontext_sid = opts->fscontext_sid; 687 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 688 fscontext_sid)) 689 goto out_double_mount; 690 sbsec->flags |= FSCONTEXT_MNT; 691 } 692 if (opts->context_sid) { 693 context_sid = opts->context_sid; 694 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 695 context_sid)) 696 goto out_double_mount; 697 sbsec->flags |= CONTEXT_MNT; 698 } 699 if (opts->rootcontext_sid) { 700 rootcontext_sid = opts->rootcontext_sid; 701 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 702 rootcontext_sid)) 703 goto out_double_mount; 704 sbsec->flags |= ROOTCONTEXT_MNT; 705 } 706 if (opts->defcontext_sid) { 707 defcontext_sid = opts->defcontext_sid; 708 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 709 defcontext_sid)) 710 goto out_double_mount; 711 sbsec->flags |= DEFCONTEXT_MNT; 712 } 713 } 714 715 if (sbsec->flags & SE_SBINITIALIZED) { 716 /* previously mounted with options, but not on this attempt? */ 717 if ((sbsec->flags & SE_MNTMASK) && !opts) 718 goto out_double_mount; 719 rc = 0; 720 goto out; 721 } 722 723 if (strcmp(sb->s_type->name, "proc") == 0) 724 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 725 726 if (!strcmp(sb->s_type->name, "debugfs") || 727 !strcmp(sb->s_type->name, "tracefs") || 728 !strcmp(sb->s_type->name, "binder") || 729 !strcmp(sb->s_type->name, "bpf") || 730 !strcmp(sb->s_type->name, "pstore") || 731 !strcmp(sb->s_type->name, "securityfs")) 732 sbsec->flags |= SE_SBGENFS; 733 734 if (!strcmp(sb->s_type->name, "sysfs") || 735 !strcmp(sb->s_type->name, "cgroup") || 736 !strcmp(sb->s_type->name, "cgroup2")) 737 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 738 739 if (!sbsec->behavior) { 740 /* 741 * Determine the labeling behavior to use for this 742 * filesystem type. 743 */ 744 rc = security_fs_use(sb); 745 if (rc) { 746 pr_warn("%s: security_fs_use(%s) returned %d\n", 747 __func__, sb->s_type->name, rc); 748 goto out; 749 } 750 } 751 752 /* 753 * If this is a user namespace mount and the filesystem type is not 754 * explicitly whitelisted, then no contexts are allowed on the command 755 * line and security labels must be ignored. 756 */ 757 if (sb->s_user_ns != &init_user_ns && 758 strcmp(sb->s_type->name, "tmpfs") && 759 strcmp(sb->s_type->name, "ramfs") && 760 strcmp(sb->s_type->name, "devpts") && 761 strcmp(sb->s_type->name, "overlay")) { 762 if (context_sid || fscontext_sid || rootcontext_sid || 763 defcontext_sid) { 764 rc = -EACCES; 765 goto out; 766 } 767 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 768 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 769 rc = security_transition_sid(current_sid(), 770 current_sid(), 771 SECCLASS_FILE, NULL, 772 &sbsec->mntpoint_sid); 773 if (rc) 774 goto out; 775 } 776 goto out_set_opts; 777 } 778 779 /* sets the context of the superblock for the fs being mounted. */ 780 if (fscontext_sid) { 781 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 782 if (rc) 783 goto out; 784 785 sbsec->sid = fscontext_sid; 786 } 787 788 /* 789 * Switch to using mount point labeling behavior. 790 * sets the label used on all file below the mountpoint, and will set 791 * the superblock context if not already set. 792 */ 793 if (sbsec->flags & SE_SBNATIVE) { 794 /* 795 * This means we are initializing a superblock that has been 796 * mounted before the SELinux was initialized and the 797 * filesystem requested native labeling. We had already 798 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags 799 * in the original mount attempt, so now we just need to set 800 * the SECURITY_FS_USE_NATIVE behavior. 801 */ 802 sbsec->behavior = SECURITY_FS_USE_NATIVE; 803 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 804 sbsec->behavior = SECURITY_FS_USE_NATIVE; 805 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 806 } 807 808 if (context_sid) { 809 if (!fscontext_sid) { 810 rc = may_context_mount_sb_relabel(context_sid, sbsec, 811 cred); 812 if (rc) 813 goto out; 814 sbsec->sid = context_sid; 815 } else { 816 rc = may_context_mount_inode_relabel(context_sid, sbsec, 817 cred); 818 if (rc) 819 goto out; 820 } 821 if (!rootcontext_sid) 822 rootcontext_sid = context_sid; 823 824 sbsec->mntpoint_sid = context_sid; 825 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 826 } 827 828 if (rootcontext_sid) { 829 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 830 cred); 831 if (rc) 832 goto out; 833 834 root_isec->sid = rootcontext_sid; 835 root_isec->initialized = LABEL_INITIALIZED; 836 } 837 838 if (defcontext_sid) { 839 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 840 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 841 rc = -EINVAL; 842 pr_warn("SELinux: defcontext option is " 843 "invalid for this filesystem type\n"); 844 goto out; 845 } 846 847 if (defcontext_sid != sbsec->def_sid) { 848 rc = may_context_mount_inode_relabel(defcontext_sid, 849 sbsec, cred); 850 if (rc) 851 goto out; 852 } 853 854 sbsec->def_sid = defcontext_sid; 855 } 856 857 out_set_opts: 858 rc = sb_finish_set_opts(sb); 859 out: 860 mutex_unlock(&sbsec->lock); 861 return rc; 862 out_double_mount: 863 rc = -EINVAL; 864 pr_warn("SELinux: mount invalid. Same superblock, different " 865 "security settings for (dev %s, type %s)\n", sb->s_id, 866 sb->s_type->name); 867 goto out; 868 } 869 870 static int selinux_cmp_sb_context(const struct super_block *oldsb, 871 const struct super_block *newsb) 872 { 873 struct superblock_security_struct *old = selinux_superblock(oldsb); 874 struct superblock_security_struct *new = selinux_superblock(newsb); 875 char oldflags = old->flags & SE_MNTMASK; 876 char newflags = new->flags & SE_MNTMASK; 877 878 if (oldflags != newflags) 879 goto mismatch; 880 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 881 goto mismatch; 882 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 883 goto mismatch; 884 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 885 goto mismatch; 886 if (oldflags & ROOTCONTEXT_MNT) { 887 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 888 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 889 if (oldroot->sid != newroot->sid) 890 goto mismatch; 891 } 892 return 0; 893 mismatch: 894 pr_warn("SELinux: mount invalid. Same superblock, " 895 "different security settings for (dev %s, " 896 "type %s)\n", newsb->s_id, newsb->s_type->name); 897 return -EBUSY; 898 } 899 900 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 901 struct super_block *newsb, 902 unsigned long kern_flags, 903 unsigned long *set_kern_flags) 904 { 905 int rc = 0; 906 const struct superblock_security_struct *oldsbsec = 907 selinux_superblock(oldsb); 908 struct superblock_security_struct *newsbsec = selinux_superblock(newsb); 909 910 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 911 int set_context = (oldsbsec->flags & CONTEXT_MNT); 912 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 913 914 /* 915 * Specifying internal flags without providing a place to 916 * place the results is not allowed. 917 */ 918 if (kern_flags && !set_kern_flags) 919 return -EINVAL; 920 921 mutex_lock(&newsbsec->lock); 922 923 /* 924 * if the parent was able to be mounted it clearly had no special lsm 925 * mount options. thus we can safely deal with this superblock later 926 */ 927 if (!selinux_initialized()) { 928 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 929 newsbsec->flags |= SE_SBNATIVE; 930 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 931 } 932 goto out; 933 } 934 935 /* how can we clone if the old one wasn't set up?? */ 936 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 937 938 /* if fs is reusing a sb, make sure that the contexts match */ 939 if (newsbsec->flags & SE_SBINITIALIZED) { 940 mutex_unlock(&newsbsec->lock); 941 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 942 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 943 return selinux_cmp_sb_context(oldsb, newsb); 944 } 945 946 newsbsec->flags = oldsbsec->flags; 947 948 newsbsec->sid = oldsbsec->sid; 949 newsbsec->def_sid = oldsbsec->def_sid; 950 newsbsec->behavior = oldsbsec->behavior; 951 952 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 953 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 954 rc = security_fs_use(newsb); 955 if (rc) 956 goto out; 957 } 958 959 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 960 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 961 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 962 } 963 964 if (set_context) { 965 u32 sid = oldsbsec->mntpoint_sid; 966 967 if (!set_fscontext) 968 newsbsec->sid = sid; 969 if (!set_rootcontext) { 970 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 971 newisec->sid = sid; 972 } 973 newsbsec->mntpoint_sid = sid; 974 } 975 if (set_rootcontext) { 976 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 977 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 978 979 newisec->sid = oldisec->sid; 980 } 981 982 sb_finish_set_opts(newsb); 983 out: 984 mutex_unlock(&newsbsec->lock); 985 return rc; 986 } 987 988 /* 989 * NOTE: the caller is responsible for freeing the memory even if on error. 990 */ 991 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 992 { 993 struct selinux_mnt_opts *opts = *mnt_opts; 994 u32 *dst_sid; 995 int rc; 996 997 if (token == Opt_seclabel) 998 /* eaten and completely ignored */ 999 return 0; 1000 if (!s) 1001 return -EINVAL; 1002 1003 if (!selinux_initialized()) { 1004 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); 1005 return -EINVAL; 1006 } 1007 1008 if (!opts) { 1009 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 1010 if (!opts) 1011 return -ENOMEM; 1012 *mnt_opts = opts; 1013 } 1014 1015 switch (token) { 1016 case Opt_context: 1017 if (opts->context_sid || opts->defcontext_sid) 1018 goto err; 1019 dst_sid = &opts->context_sid; 1020 break; 1021 case Opt_fscontext: 1022 if (opts->fscontext_sid) 1023 goto err; 1024 dst_sid = &opts->fscontext_sid; 1025 break; 1026 case Opt_rootcontext: 1027 if (opts->rootcontext_sid) 1028 goto err; 1029 dst_sid = &opts->rootcontext_sid; 1030 break; 1031 case Opt_defcontext: 1032 if (opts->context_sid || opts->defcontext_sid) 1033 goto err; 1034 dst_sid = &opts->defcontext_sid; 1035 break; 1036 default: 1037 WARN_ON(1); 1038 return -EINVAL; 1039 } 1040 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); 1041 if (rc) 1042 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", 1043 s, rc); 1044 return rc; 1045 1046 err: 1047 pr_warn(SEL_MOUNT_FAIL_MSG); 1048 return -EINVAL; 1049 } 1050 1051 static int show_sid(struct seq_file *m, u32 sid) 1052 { 1053 char *context = NULL; 1054 u32 len; 1055 int rc; 1056 1057 rc = security_sid_to_context(sid, &context, &len); 1058 if (!rc) { 1059 bool has_comma = strchr(context, ','); 1060 1061 seq_putc(m, '='); 1062 if (has_comma) 1063 seq_putc(m, '\"'); 1064 seq_escape(m, context, "\"\n\\"); 1065 if (has_comma) 1066 seq_putc(m, '\"'); 1067 } 1068 kfree(context); 1069 return rc; 1070 } 1071 1072 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1073 { 1074 struct superblock_security_struct *sbsec = selinux_superblock(sb); 1075 int rc; 1076 1077 if (!(sbsec->flags & SE_SBINITIALIZED)) 1078 return 0; 1079 1080 if (!selinux_initialized()) 1081 return 0; 1082 1083 if (sbsec->flags & FSCONTEXT_MNT) { 1084 seq_putc(m, ','); 1085 seq_puts(m, FSCONTEXT_STR); 1086 rc = show_sid(m, sbsec->sid); 1087 if (rc) 1088 return rc; 1089 } 1090 if (sbsec->flags & CONTEXT_MNT) { 1091 seq_putc(m, ','); 1092 seq_puts(m, CONTEXT_STR); 1093 rc = show_sid(m, sbsec->mntpoint_sid); 1094 if (rc) 1095 return rc; 1096 } 1097 if (sbsec->flags & DEFCONTEXT_MNT) { 1098 seq_putc(m, ','); 1099 seq_puts(m, DEFCONTEXT_STR); 1100 rc = show_sid(m, sbsec->def_sid); 1101 if (rc) 1102 return rc; 1103 } 1104 if (sbsec->flags & ROOTCONTEXT_MNT) { 1105 struct dentry *root = sb->s_root; 1106 struct inode_security_struct *isec = backing_inode_security(root); 1107 seq_putc(m, ','); 1108 seq_puts(m, ROOTCONTEXT_STR); 1109 rc = show_sid(m, isec->sid); 1110 if (rc) 1111 return rc; 1112 } 1113 if (sbsec->flags & SBLABEL_MNT) { 1114 seq_putc(m, ','); 1115 seq_puts(m, SECLABEL_STR); 1116 } 1117 return 0; 1118 } 1119 1120 static inline u16 inode_mode_to_security_class(umode_t mode) 1121 { 1122 switch (mode & S_IFMT) { 1123 case S_IFSOCK: 1124 return SECCLASS_SOCK_FILE; 1125 case S_IFLNK: 1126 return SECCLASS_LNK_FILE; 1127 case S_IFREG: 1128 return SECCLASS_FILE; 1129 case S_IFBLK: 1130 return SECCLASS_BLK_FILE; 1131 case S_IFDIR: 1132 return SECCLASS_DIR; 1133 case S_IFCHR: 1134 return SECCLASS_CHR_FILE; 1135 case S_IFIFO: 1136 return SECCLASS_FIFO_FILE; 1137 1138 } 1139 1140 return SECCLASS_FILE; 1141 } 1142 1143 static inline int default_protocol_stream(int protocol) 1144 { 1145 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || 1146 protocol == IPPROTO_MPTCP); 1147 } 1148 1149 static inline int default_protocol_dgram(int protocol) 1150 { 1151 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1152 } 1153 1154 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1155 { 1156 bool extsockclass = selinux_policycap_extsockclass(); 1157 1158 switch (family) { 1159 case PF_UNIX: 1160 switch (type) { 1161 case SOCK_STREAM: 1162 case SOCK_SEQPACKET: 1163 return SECCLASS_UNIX_STREAM_SOCKET; 1164 case SOCK_DGRAM: 1165 case SOCK_RAW: 1166 return SECCLASS_UNIX_DGRAM_SOCKET; 1167 } 1168 break; 1169 case PF_INET: 1170 case PF_INET6: 1171 switch (type) { 1172 case SOCK_STREAM: 1173 case SOCK_SEQPACKET: 1174 if (default_protocol_stream(protocol)) 1175 return SECCLASS_TCP_SOCKET; 1176 else if (extsockclass && protocol == IPPROTO_SCTP) 1177 return SECCLASS_SCTP_SOCKET; 1178 else 1179 return SECCLASS_RAWIP_SOCKET; 1180 case SOCK_DGRAM: 1181 if (default_protocol_dgram(protocol)) 1182 return SECCLASS_UDP_SOCKET; 1183 else if (extsockclass && (protocol == IPPROTO_ICMP || 1184 protocol == IPPROTO_ICMPV6)) 1185 return SECCLASS_ICMP_SOCKET; 1186 else 1187 return SECCLASS_RAWIP_SOCKET; 1188 case SOCK_DCCP: 1189 return SECCLASS_DCCP_SOCKET; 1190 default: 1191 return SECCLASS_RAWIP_SOCKET; 1192 } 1193 break; 1194 case PF_NETLINK: 1195 switch (protocol) { 1196 case NETLINK_ROUTE: 1197 return SECCLASS_NETLINK_ROUTE_SOCKET; 1198 case NETLINK_SOCK_DIAG: 1199 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1200 case NETLINK_NFLOG: 1201 return SECCLASS_NETLINK_NFLOG_SOCKET; 1202 case NETLINK_XFRM: 1203 return SECCLASS_NETLINK_XFRM_SOCKET; 1204 case NETLINK_SELINUX: 1205 return SECCLASS_NETLINK_SELINUX_SOCKET; 1206 case NETLINK_ISCSI: 1207 return SECCLASS_NETLINK_ISCSI_SOCKET; 1208 case NETLINK_AUDIT: 1209 return SECCLASS_NETLINK_AUDIT_SOCKET; 1210 case NETLINK_FIB_LOOKUP: 1211 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1212 case NETLINK_CONNECTOR: 1213 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1214 case NETLINK_NETFILTER: 1215 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1216 case NETLINK_DNRTMSG: 1217 return SECCLASS_NETLINK_DNRT_SOCKET; 1218 case NETLINK_KOBJECT_UEVENT: 1219 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1220 case NETLINK_GENERIC: 1221 return SECCLASS_NETLINK_GENERIC_SOCKET; 1222 case NETLINK_SCSITRANSPORT: 1223 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1224 case NETLINK_RDMA: 1225 return SECCLASS_NETLINK_RDMA_SOCKET; 1226 case NETLINK_CRYPTO: 1227 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1228 default: 1229 return SECCLASS_NETLINK_SOCKET; 1230 } 1231 case PF_PACKET: 1232 return SECCLASS_PACKET_SOCKET; 1233 case PF_KEY: 1234 return SECCLASS_KEY_SOCKET; 1235 case PF_APPLETALK: 1236 return SECCLASS_APPLETALK_SOCKET; 1237 } 1238 1239 if (extsockclass) { 1240 switch (family) { 1241 case PF_AX25: 1242 return SECCLASS_AX25_SOCKET; 1243 case PF_IPX: 1244 return SECCLASS_IPX_SOCKET; 1245 case PF_NETROM: 1246 return SECCLASS_NETROM_SOCKET; 1247 case PF_ATMPVC: 1248 return SECCLASS_ATMPVC_SOCKET; 1249 case PF_X25: 1250 return SECCLASS_X25_SOCKET; 1251 case PF_ROSE: 1252 return SECCLASS_ROSE_SOCKET; 1253 case PF_DECnet: 1254 return SECCLASS_DECNET_SOCKET; 1255 case PF_ATMSVC: 1256 return SECCLASS_ATMSVC_SOCKET; 1257 case PF_RDS: 1258 return SECCLASS_RDS_SOCKET; 1259 case PF_IRDA: 1260 return SECCLASS_IRDA_SOCKET; 1261 case PF_PPPOX: 1262 return SECCLASS_PPPOX_SOCKET; 1263 case PF_LLC: 1264 return SECCLASS_LLC_SOCKET; 1265 case PF_CAN: 1266 return SECCLASS_CAN_SOCKET; 1267 case PF_TIPC: 1268 return SECCLASS_TIPC_SOCKET; 1269 case PF_BLUETOOTH: 1270 return SECCLASS_BLUETOOTH_SOCKET; 1271 case PF_IUCV: 1272 return SECCLASS_IUCV_SOCKET; 1273 case PF_RXRPC: 1274 return SECCLASS_RXRPC_SOCKET; 1275 case PF_ISDN: 1276 return SECCLASS_ISDN_SOCKET; 1277 case PF_PHONET: 1278 return SECCLASS_PHONET_SOCKET; 1279 case PF_IEEE802154: 1280 return SECCLASS_IEEE802154_SOCKET; 1281 case PF_CAIF: 1282 return SECCLASS_CAIF_SOCKET; 1283 case PF_ALG: 1284 return SECCLASS_ALG_SOCKET; 1285 case PF_NFC: 1286 return SECCLASS_NFC_SOCKET; 1287 case PF_VSOCK: 1288 return SECCLASS_VSOCK_SOCKET; 1289 case PF_KCM: 1290 return SECCLASS_KCM_SOCKET; 1291 case PF_QIPCRTR: 1292 return SECCLASS_QIPCRTR_SOCKET; 1293 case PF_SMC: 1294 return SECCLASS_SMC_SOCKET; 1295 case PF_XDP: 1296 return SECCLASS_XDP_SOCKET; 1297 case PF_MCTP: 1298 return SECCLASS_MCTP_SOCKET; 1299 #if PF_MAX > 46 1300 #error New address family defined, please update this function. 1301 #endif 1302 } 1303 } 1304 1305 return SECCLASS_SOCKET; 1306 } 1307 1308 static int selinux_genfs_get_sid(struct dentry *dentry, 1309 u16 tclass, 1310 u16 flags, 1311 u32 *sid) 1312 { 1313 int rc; 1314 struct super_block *sb = dentry->d_sb; 1315 char *buffer, *path; 1316 1317 buffer = (char *)__get_free_page(GFP_KERNEL); 1318 if (!buffer) 1319 return -ENOMEM; 1320 1321 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1322 if (IS_ERR(path)) 1323 rc = PTR_ERR(path); 1324 else { 1325 if (flags & SE_SBPROC) { 1326 /* each process gets a /proc/PID/ entry. Strip off the 1327 * PID part to get a valid selinux labeling. 1328 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1329 while (path[1] >= '0' && path[1] <= '9') { 1330 path[1] = '/'; 1331 path++; 1332 } 1333 } 1334 rc = security_genfs_sid(sb->s_type->name, 1335 path, tclass, sid); 1336 if (rc == -ENOENT) { 1337 /* No match in policy, mark as unlabeled. */ 1338 *sid = SECINITSID_UNLABELED; 1339 rc = 0; 1340 } 1341 } 1342 free_page((unsigned long)buffer); 1343 return rc; 1344 } 1345 1346 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1347 u32 def_sid, u32 *sid) 1348 { 1349 #define INITCONTEXTLEN 255 1350 char *context; 1351 unsigned int len; 1352 int rc; 1353 1354 len = INITCONTEXTLEN; 1355 context = kmalloc(len + 1, GFP_NOFS); 1356 if (!context) 1357 return -ENOMEM; 1358 1359 context[len] = '\0'; 1360 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1361 if (rc == -ERANGE) { 1362 kfree(context); 1363 1364 /* Need a larger buffer. Query for the right size. */ 1365 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1366 if (rc < 0) 1367 return rc; 1368 1369 len = rc; 1370 context = kmalloc(len + 1, GFP_NOFS); 1371 if (!context) 1372 return -ENOMEM; 1373 1374 context[len] = '\0'; 1375 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1376 context, len); 1377 } 1378 if (rc < 0) { 1379 kfree(context); 1380 if (rc != -ENODATA) { 1381 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1382 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1383 return rc; 1384 } 1385 *sid = def_sid; 1386 return 0; 1387 } 1388 1389 rc = security_context_to_sid_default(context, rc, sid, 1390 def_sid, GFP_NOFS); 1391 if (rc) { 1392 char *dev = inode->i_sb->s_id; 1393 unsigned long ino = inode->i_ino; 1394 1395 if (rc == -EINVAL) { 1396 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", 1397 ino, dev, context); 1398 } else { 1399 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1400 __func__, context, -rc, dev, ino); 1401 } 1402 } 1403 kfree(context); 1404 return 0; 1405 } 1406 1407 /* The inode's security attributes must be initialized before first use. */ 1408 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1409 { 1410 struct superblock_security_struct *sbsec = NULL; 1411 struct inode_security_struct *isec = selinux_inode(inode); 1412 u32 task_sid, sid = 0; 1413 u16 sclass; 1414 struct dentry *dentry; 1415 int rc = 0; 1416 1417 if (isec->initialized == LABEL_INITIALIZED) 1418 return 0; 1419 1420 spin_lock(&isec->lock); 1421 if (isec->initialized == LABEL_INITIALIZED) 1422 goto out_unlock; 1423 1424 if (isec->sclass == SECCLASS_FILE) 1425 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1426 1427 sbsec = selinux_superblock(inode->i_sb); 1428 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1429 /* Defer initialization until selinux_complete_init, 1430 after the initial policy is loaded and the security 1431 server is ready to handle calls. */ 1432 spin_lock(&sbsec->isec_lock); 1433 if (list_empty(&isec->list)) 1434 list_add(&isec->list, &sbsec->isec_head); 1435 spin_unlock(&sbsec->isec_lock); 1436 goto out_unlock; 1437 } 1438 1439 sclass = isec->sclass; 1440 task_sid = isec->task_sid; 1441 sid = isec->sid; 1442 isec->initialized = LABEL_PENDING; 1443 spin_unlock(&isec->lock); 1444 1445 switch (sbsec->behavior) { 1446 /* 1447 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels 1448 * via xattr when called from delayed_superblock_init(). 1449 */ 1450 case SECURITY_FS_USE_NATIVE: 1451 case SECURITY_FS_USE_XATTR: 1452 if (!(inode->i_opflags & IOP_XATTR)) { 1453 sid = sbsec->def_sid; 1454 break; 1455 } 1456 /* Need a dentry, since the xattr API requires one. 1457 Life would be simpler if we could just pass the inode. */ 1458 if (opt_dentry) { 1459 /* Called from d_instantiate or d_splice_alias. */ 1460 dentry = dget(opt_dentry); 1461 } else { 1462 /* 1463 * Called from selinux_complete_init, try to find a dentry. 1464 * Some filesystems really want a connected one, so try 1465 * that first. We could split SECURITY_FS_USE_XATTR in 1466 * two, depending upon that... 1467 */ 1468 dentry = d_find_alias(inode); 1469 if (!dentry) 1470 dentry = d_find_any_alias(inode); 1471 } 1472 if (!dentry) { 1473 /* 1474 * this is can be hit on boot when a file is accessed 1475 * before the policy is loaded. When we load policy we 1476 * may find inodes that have no dentry on the 1477 * sbsec->isec_head list. No reason to complain as these 1478 * will get fixed up the next time we go through 1479 * inode_doinit with a dentry, before these inodes could 1480 * be used again by userspace. 1481 */ 1482 goto out_invalid; 1483 } 1484 1485 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1486 &sid); 1487 dput(dentry); 1488 if (rc) 1489 goto out; 1490 break; 1491 case SECURITY_FS_USE_TASK: 1492 sid = task_sid; 1493 break; 1494 case SECURITY_FS_USE_TRANS: 1495 /* Default to the fs SID. */ 1496 sid = sbsec->sid; 1497 1498 /* Try to obtain a transition SID. */ 1499 rc = security_transition_sid(task_sid, sid, 1500 sclass, NULL, &sid); 1501 if (rc) 1502 goto out; 1503 break; 1504 case SECURITY_FS_USE_MNTPOINT: 1505 sid = sbsec->mntpoint_sid; 1506 break; 1507 default: 1508 /* Default to the fs superblock SID. */ 1509 sid = sbsec->sid; 1510 1511 if ((sbsec->flags & SE_SBGENFS) && 1512 (!S_ISLNK(inode->i_mode) || 1513 selinux_policycap_genfs_seclabel_symlinks())) { 1514 /* We must have a dentry to determine the label on 1515 * procfs inodes */ 1516 if (opt_dentry) { 1517 /* Called from d_instantiate or 1518 * d_splice_alias. */ 1519 dentry = dget(opt_dentry); 1520 } else { 1521 /* Called from selinux_complete_init, try to 1522 * find a dentry. Some filesystems really want 1523 * a connected one, so try that first. 1524 */ 1525 dentry = d_find_alias(inode); 1526 if (!dentry) 1527 dentry = d_find_any_alias(inode); 1528 } 1529 /* 1530 * This can be hit on boot when a file is accessed 1531 * before the policy is loaded. When we load policy we 1532 * may find inodes that have no dentry on the 1533 * sbsec->isec_head list. No reason to complain as 1534 * these will get fixed up the next time we go through 1535 * inode_doinit() with a dentry, before these inodes 1536 * could be used again by userspace. 1537 */ 1538 if (!dentry) 1539 goto out_invalid; 1540 rc = selinux_genfs_get_sid(dentry, sclass, 1541 sbsec->flags, &sid); 1542 if (rc) { 1543 dput(dentry); 1544 goto out; 1545 } 1546 1547 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1548 (inode->i_opflags & IOP_XATTR)) { 1549 rc = inode_doinit_use_xattr(inode, dentry, 1550 sid, &sid); 1551 if (rc) { 1552 dput(dentry); 1553 goto out; 1554 } 1555 } 1556 dput(dentry); 1557 } 1558 break; 1559 } 1560 1561 out: 1562 spin_lock(&isec->lock); 1563 if (isec->initialized == LABEL_PENDING) { 1564 if (rc) { 1565 isec->initialized = LABEL_INVALID; 1566 goto out_unlock; 1567 } 1568 isec->initialized = LABEL_INITIALIZED; 1569 isec->sid = sid; 1570 } 1571 1572 out_unlock: 1573 spin_unlock(&isec->lock); 1574 return rc; 1575 1576 out_invalid: 1577 spin_lock(&isec->lock); 1578 if (isec->initialized == LABEL_PENDING) { 1579 isec->initialized = LABEL_INVALID; 1580 isec->sid = sid; 1581 } 1582 spin_unlock(&isec->lock); 1583 return 0; 1584 } 1585 1586 /* Convert a Linux signal to an access vector. */ 1587 static inline u32 signal_to_av(int sig) 1588 { 1589 u32 perm = 0; 1590 1591 switch (sig) { 1592 case SIGCHLD: 1593 /* Commonly granted from child to parent. */ 1594 perm = PROCESS__SIGCHLD; 1595 break; 1596 case SIGKILL: 1597 /* Cannot be caught or ignored */ 1598 perm = PROCESS__SIGKILL; 1599 break; 1600 case SIGSTOP: 1601 /* Cannot be caught or ignored */ 1602 perm = PROCESS__SIGSTOP; 1603 break; 1604 default: 1605 /* All other signals. */ 1606 perm = PROCESS__SIGNAL; 1607 break; 1608 } 1609 1610 return perm; 1611 } 1612 1613 #if CAP_LAST_CAP > 63 1614 #error Fix SELinux to handle capabilities > 63. 1615 #endif 1616 1617 /* Check whether a task is allowed to use a capability. */ 1618 static int cred_has_capability(const struct cred *cred, 1619 int cap, unsigned int opts, bool initns) 1620 { 1621 struct common_audit_data ad; 1622 struct av_decision avd; 1623 u16 sclass; 1624 u32 sid = cred_sid(cred); 1625 u32 av = CAP_TO_MASK(cap); 1626 int rc; 1627 1628 ad.type = LSM_AUDIT_DATA_CAP; 1629 ad.u.cap = cap; 1630 1631 switch (CAP_TO_INDEX(cap)) { 1632 case 0: 1633 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1634 break; 1635 case 1: 1636 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1637 break; 1638 default: 1639 pr_err("SELinux: out of range capability %d\n", cap); 1640 BUG(); 1641 return -EINVAL; 1642 } 1643 1644 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1645 if (!(opts & CAP_OPT_NOAUDIT)) { 1646 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1647 if (rc2) 1648 return rc2; 1649 } 1650 return rc; 1651 } 1652 1653 /* Check whether a task has a particular permission to an inode. 1654 The 'adp' parameter is optional and allows other audit 1655 data to be passed (e.g. the dentry). */ 1656 static int inode_has_perm(const struct cred *cred, 1657 struct inode *inode, 1658 u32 perms, 1659 struct common_audit_data *adp) 1660 { 1661 struct inode_security_struct *isec; 1662 u32 sid; 1663 1664 validate_creds(cred); 1665 1666 if (unlikely(IS_PRIVATE(inode))) 1667 return 0; 1668 1669 sid = cred_sid(cred); 1670 isec = selinux_inode(inode); 1671 1672 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1673 } 1674 1675 /* Same as inode_has_perm, but pass explicit audit data containing 1676 the dentry to help the auditing code to more easily generate the 1677 pathname if needed. */ 1678 static inline int dentry_has_perm(const struct cred *cred, 1679 struct dentry *dentry, 1680 u32 av) 1681 { 1682 struct inode *inode = d_backing_inode(dentry); 1683 struct common_audit_data ad; 1684 1685 ad.type = LSM_AUDIT_DATA_DENTRY; 1686 ad.u.dentry = dentry; 1687 __inode_security_revalidate(inode, dentry, true); 1688 return inode_has_perm(cred, inode, av, &ad); 1689 } 1690 1691 /* Same as inode_has_perm, but pass explicit audit data containing 1692 the path to help the auditing code to more easily generate the 1693 pathname if needed. */ 1694 static inline int path_has_perm(const struct cred *cred, 1695 const struct path *path, 1696 u32 av) 1697 { 1698 struct inode *inode = d_backing_inode(path->dentry); 1699 struct common_audit_data ad; 1700 1701 ad.type = LSM_AUDIT_DATA_PATH; 1702 ad.u.path = *path; 1703 __inode_security_revalidate(inode, path->dentry, true); 1704 return inode_has_perm(cred, inode, av, &ad); 1705 } 1706 1707 /* Same as path_has_perm, but uses the inode from the file struct. */ 1708 static inline int file_path_has_perm(const struct cred *cred, 1709 struct file *file, 1710 u32 av) 1711 { 1712 struct common_audit_data ad; 1713 1714 ad.type = LSM_AUDIT_DATA_FILE; 1715 ad.u.file = file; 1716 return inode_has_perm(cred, file_inode(file), av, &ad); 1717 } 1718 1719 #ifdef CONFIG_BPF_SYSCALL 1720 static int bpf_fd_pass(const struct file *file, u32 sid); 1721 #endif 1722 1723 /* Check whether a task can use an open file descriptor to 1724 access an inode in a given way. Check access to the 1725 descriptor itself, and then use dentry_has_perm to 1726 check a particular permission to the file. 1727 Access to the descriptor is implicitly granted if it 1728 has the same SID as the process. If av is zero, then 1729 access to the file is not checked, e.g. for cases 1730 where only the descriptor is affected like seek. */ 1731 static int file_has_perm(const struct cred *cred, 1732 struct file *file, 1733 u32 av) 1734 { 1735 struct file_security_struct *fsec = selinux_file(file); 1736 struct inode *inode = file_inode(file); 1737 struct common_audit_data ad; 1738 u32 sid = cred_sid(cred); 1739 int rc; 1740 1741 ad.type = LSM_AUDIT_DATA_FILE; 1742 ad.u.file = file; 1743 1744 if (sid != fsec->sid) { 1745 rc = avc_has_perm(sid, fsec->sid, 1746 SECCLASS_FD, 1747 FD__USE, 1748 &ad); 1749 if (rc) 1750 goto out; 1751 } 1752 1753 #ifdef CONFIG_BPF_SYSCALL 1754 rc = bpf_fd_pass(file, cred_sid(cred)); 1755 if (rc) 1756 return rc; 1757 #endif 1758 1759 /* av is zero if only checking access to the descriptor. */ 1760 rc = 0; 1761 if (av) 1762 rc = inode_has_perm(cred, inode, av, &ad); 1763 1764 out: 1765 return rc; 1766 } 1767 1768 /* 1769 * Determine the label for an inode that might be unioned. 1770 */ 1771 static int 1772 selinux_determine_inode_label(const struct task_security_struct *tsec, 1773 struct inode *dir, 1774 const struct qstr *name, u16 tclass, 1775 u32 *_new_isid) 1776 { 1777 const struct superblock_security_struct *sbsec = 1778 selinux_superblock(dir->i_sb); 1779 1780 if ((sbsec->flags & SE_SBINITIALIZED) && 1781 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1782 *_new_isid = sbsec->mntpoint_sid; 1783 } else if ((sbsec->flags & SBLABEL_MNT) && 1784 tsec->create_sid) { 1785 *_new_isid = tsec->create_sid; 1786 } else { 1787 const struct inode_security_struct *dsec = inode_security(dir); 1788 return security_transition_sid(tsec->sid, 1789 dsec->sid, tclass, 1790 name, _new_isid); 1791 } 1792 1793 return 0; 1794 } 1795 1796 /* Check whether a task can create a file. */ 1797 static int may_create(struct inode *dir, 1798 struct dentry *dentry, 1799 u16 tclass) 1800 { 1801 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1802 struct inode_security_struct *dsec; 1803 struct superblock_security_struct *sbsec; 1804 u32 sid, newsid; 1805 struct common_audit_data ad; 1806 int rc; 1807 1808 dsec = inode_security(dir); 1809 sbsec = selinux_superblock(dir->i_sb); 1810 1811 sid = tsec->sid; 1812 1813 ad.type = LSM_AUDIT_DATA_DENTRY; 1814 ad.u.dentry = dentry; 1815 1816 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1817 DIR__ADD_NAME | DIR__SEARCH, 1818 &ad); 1819 if (rc) 1820 return rc; 1821 1822 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1823 &newsid); 1824 if (rc) 1825 return rc; 1826 1827 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1828 if (rc) 1829 return rc; 1830 1831 return avc_has_perm(newsid, sbsec->sid, 1832 SECCLASS_FILESYSTEM, 1833 FILESYSTEM__ASSOCIATE, &ad); 1834 } 1835 1836 #define MAY_LINK 0 1837 #define MAY_UNLINK 1 1838 #define MAY_RMDIR 2 1839 1840 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1841 static int may_link(struct inode *dir, 1842 struct dentry *dentry, 1843 int kind) 1844 1845 { 1846 struct inode_security_struct *dsec, *isec; 1847 struct common_audit_data ad; 1848 u32 sid = current_sid(); 1849 u32 av; 1850 int rc; 1851 1852 dsec = inode_security(dir); 1853 isec = backing_inode_security(dentry); 1854 1855 ad.type = LSM_AUDIT_DATA_DENTRY; 1856 ad.u.dentry = dentry; 1857 1858 av = DIR__SEARCH; 1859 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1860 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1861 if (rc) 1862 return rc; 1863 1864 switch (kind) { 1865 case MAY_LINK: 1866 av = FILE__LINK; 1867 break; 1868 case MAY_UNLINK: 1869 av = FILE__UNLINK; 1870 break; 1871 case MAY_RMDIR: 1872 av = DIR__RMDIR; 1873 break; 1874 default: 1875 pr_warn("SELinux: %s: unrecognized kind %d\n", 1876 __func__, kind); 1877 return 0; 1878 } 1879 1880 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1881 return rc; 1882 } 1883 1884 static inline int may_rename(struct inode *old_dir, 1885 struct dentry *old_dentry, 1886 struct inode *new_dir, 1887 struct dentry *new_dentry) 1888 { 1889 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1890 struct common_audit_data ad; 1891 u32 sid = current_sid(); 1892 u32 av; 1893 int old_is_dir, new_is_dir; 1894 int rc; 1895 1896 old_dsec = inode_security(old_dir); 1897 old_isec = backing_inode_security(old_dentry); 1898 old_is_dir = d_is_dir(old_dentry); 1899 new_dsec = inode_security(new_dir); 1900 1901 ad.type = LSM_AUDIT_DATA_DENTRY; 1902 1903 ad.u.dentry = old_dentry; 1904 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1905 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1906 if (rc) 1907 return rc; 1908 rc = avc_has_perm(sid, old_isec->sid, 1909 old_isec->sclass, FILE__RENAME, &ad); 1910 if (rc) 1911 return rc; 1912 if (old_is_dir && new_dir != old_dir) { 1913 rc = avc_has_perm(sid, old_isec->sid, 1914 old_isec->sclass, DIR__REPARENT, &ad); 1915 if (rc) 1916 return rc; 1917 } 1918 1919 ad.u.dentry = new_dentry; 1920 av = DIR__ADD_NAME | DIR__SEARCH; 1921 if (d_is_positive(new_dentry)) 1922 av |= DIR__REMOVE_NAME; 1923 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1924 if (rc) 1925 return rc; 1926 if (d_is_positive(new_dentry)) { 1927 new_isec = backing_inode_security(new_dentry); 1928 new_is_dir = d_is_dir(new_dentry); 1929 rc = avc_has_perm(sid, new_isec->sid, 1930 new_isec->sclass, 1931 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1932 if (rc) 1933 return rc; 1934 } 1935 1936 return 0; 1937 } 1938 1939 /* Check whether a task can perform a filesystem operation. */ 1940 static int superblock_has_perm(const struct cred *cred, 1941 const struct super_block *sb, 1942 u32 perms, 1943 struct common_audit_data *ad) 1944 { 1945 struct superblock_security_struct *sbsec; 1946 u32 sid = cred_sid(cred); 1947 1948 sbsec = selinux_superblock(sb); 1949 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1950 } 1951 1952 /* Convert a Linux mode and permission mask to an access vector. */ 1953 static inline u32 file_mask_to_av(int mode, int mask) 1954 { 1955 u32 av = 0; 1956 1957 if (!S_ISDIR(mode)) { 1958 if (mask & MAY_EXEC) 1959 av |= FILE__EXECUTE; 1960 if (mask & MAY_READ) 1961 av |= FILE__READ; 1962 1963 if (mask & MAY_APPEND) 1964 av |= FILE__APPEND; 1965 else if (mask & MAY_WRITE) 1966 av |= FILE__WRITE; 1967 1968 } else { 1969 if (mask & MAY_EXEC) 1970 av |= DIR__SEARCH; 1971 if (mask & MAY_WRITE) 1972 av |= DIR__WRITE; 1973 if (mask & MAY_READ) 1974 av |= DIR__READ; 1975 } 1976 1977 return av; 1978 } 1979 1980 /* Convert a Linux file to an access vector. */ 1981 static inline u32 file_to_av(const struct file *file) 1982 { 1983 u32 av = 0; 1984 1985 if (file->f_mode & FMODE_READ) 1986 av |= FILE__READ; 1987 if (file->f_mode & FMODE_WRITE) { 1988 if (file->f_flags & O_APPEND) 1989 av |= FILE__APPEND; 1990 else 1991 av |= FILE__WRITE; 1992 } 1993 if (!av) { 1994 /* 1995 * Special file opened with flags 3 for ioctl-only use. 1996 */ 1997 av = FILE__IOCTL; 1998 } 1999 2000 return av; 2001 } 2002 2003 /* 2004 * Convert a file to an access vector and include the correct 2005 * open permission. 2006 */ 2007 static inline u32 open_file_to_av(struct file *file) 2008 { 2009 u32 av = file_to_av(file); 2010 struct inode *inode = file_inode(file); 2011 2012 if (selinux_policycap_openperm() && 2013 inode->i_sb->s_magic != SOCKFS_MAGIC) 2014 av |= FILE__OPEN; 2015 2016 return av; 2017 } 2018 2019 /* Hook functions begin here. */ 2020 2021 static int selinux_binder_set_context_mgr(const struct cred *mgr) 2022 { 2023 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, 2024 BINDER__SET_CONTEXT_MGR, NULL); 2025 } 2026 2027 static int selinux_binder_transaction(const struct cred *from, 2028 const struct cred *to) 2029 { 2030 u32 mysid = current_sid(); 2031 u32 fromsid = cred_sid(from); 2032 u32 tosid = cred_sid(to); 2033 int rc; 2034 2035 if (mysid != fromsid) { 2036 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2037 BINDER__IMPERSONATE, NULL); 2038 if (rc) 2039 return rc; 2040 } 2041 2042 return avc_has_perm(fromsid, tosid, 2043 SECCLASS_BINDER, BINDER__CALL, NULL); 2044 } 2045 2046 static int selinux_binder_transfer_binder(const struct cred *from, 2047 const struct cred *to) 2048 { 2049 return avc_has_perm(cred_sid(from), cred_sid(to), 2050 SECCLASS_BINDER, BINDER__TRANSFER, 2051 NULL); 2052 } 2053 2054 static int selinux_binder_transfer_file(const struct cred *from, 2055 const struct cred *to, 2056 const struct file *file) 2057 { 2058 u32 sid = cred_sid(to); 2059 struct file_security_struct *fsec = selinux_file(file); 2060 struct dentry *dentry = file->f_path.dentry; 2061 struct inode_security_struct *isec; 2062 struct common_audit_data ad; 2063 int rc; 2064 2065 ad.type = LSM_AUDIT_DATA_PATH; 2066 ad.u.path = file->f_path; 2067 2068 if (sid != fsec->sid) { 2069 rc = avc_has_perm(sid, fsec->sid, 2070 SECCLASS_FD, 2071 FD__USE, 2072 &ad); 2073 if (rc) 2074 return rc; 2075 } 2076 2077 #ifdef CONFIG_BPF_SYSCALL 2078 rc = bpf_fd_pass(file, sid); 2079 if (rc) 2080 return rc; 2081 #endif 2082 2083 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2084 return 0; 2085 2086 isec = backing_inode_security(dentry); 2087 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2088 &ad); 2089 } 2090 2091 static int selinux_ptrace_access_check(struct task_struct *child, 2092 unsigned int mode) 2093 { 2094 u32 sid = current_sid(); 2095 u32 csid = task_sid_obj(child); 2096 2097 if (mode & PTRACE_MODE_READ) 2098 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, 2099 NULL); 2100 2101 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, 2102 NULL); 2103 } 2104 2105 static int selinux_ptrace_traceme(struct task_struct *parent) 2106 { 2107 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), 2108 SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2109 } 2110 2111 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, 2112 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2113 { 2114 return avc_has_perm(current_sid(), task_sid_obj(target), 2115 SECCLASS_PROCESS, PROCESS__GETCAP, NULL); 2116 } 2117 2118 static int selinux_capset(struct cred *new, const struct cred *old, 2119 const kernel_cap_t *effective, 2120 const kernel_cap_t *inheritable, 2121 const kernel_cap_t *permitted) 2122 { 2123 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2124 PROCESS__SETCAP, NULL); 2125 } 2126 2127 /* 2128 * (This comment used to live with the selinux_task_setuid hook, 2129 * which was removed). 2130 * 2131 * Since setuid only affects the current process, and since the SELinux 2132 * controls are not based on the Linux identity attributes, SELinux does not 2133 * need to control this operation. However, SELinux does control the use of 2134 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2135 */ 2136 2137 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2138 int cap, unsigned int opts) 2139 { 2140 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2141 } 2142 2143 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb) 2144 { 2145 const struct cred *cred = current_cred(); 2146 int rc = 0; 2147 2148 if (!sb) 2149 return 0; 2150 2151 switch (cmds) { 2152 case Q_SYNC: 2153 case Q_QUOTAON: 2154 case Q_QUOTAOFF: 2155 case Q_SETINFO: 2156 case Q_SETQUOTA: 2157 case Q_XQUOTAOFF: 2158 case Q_XQUOTAON: 2159 case Q_XSETQLIM: 2160 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2161 break; 2162 case Q_GETFMT: 2163 case Q_GETINFO: 2164 case Q_GETQUOTA: 2165 case Q_XGETQUOTA: 2166 case Q_XGETQSTAT: 2167 case Q_XGETQSTATV: 2168 case Q_XGETNEXTQUOTA: 2169 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2170 break; 2171 default: 2172 rc = 0; /* let the kernel handle invalid cmds */ 2173 break; 2174 } 2175 return rc; 2176 } 2177 2178 static int selinux_quota_on(struct dentry *dentry) 2179 { 2180 const struct cred *cred = current_cred(); 2181 2182 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2183 } 2184 2185 static int selinux_syslog(int type) 2186 { 2187 switch (type) { 2188 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2189 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2190 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2191 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2192 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2193 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2194 /* Set level of messages printed to console */ 2195 case SYSLOG_ACTION_CONSOLE_LEVEL: 2196 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2197 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2198 NULL); 2199 } 2200 /* All other syslog types */ 2201 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2202 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2203 } 2204 2205 /* 2206 * Check that a process has enough memory to allocate a new virtual 2207 * mapping. 0 means there is enough memory for the allocation to 2208 * succeed and -ENOMEM implies there is not. 2209 * 2210 * Do not audit the selinux permission check, as this is applied to all 2211 * processes that allocate mappings. 2212 */ 2213 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2214 { 2215 int rc, cap_sys_admin = 0; 2216 2217 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2218 CAP_OPT_NOAUDIT, true); 2219 if (rc == 0) 2220 cap_sys_admin = 1; 2221 2222 return cap_sys_admin; 2223 } 2224 2225 /* binprm security operations */ 2226 2227 static u32 ptrace_parent_sid(void) 2228 { 2229 u32 sid = 0; 2230 struct task_struct *tracer; 2231 2232 rcu_read_lock(); 2233 tracer = ptrace_parent(current); 2234 if (tracer) 2235 sid = task_sid_obj(tracer); 2236 rcu_read_unlock(); 2237 2238 return sid; 2239 } 2240 2241 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2242 const struct task_security_struct *old_tsec, 2243 const struct task_security_struct *new_tsec) 2244 { 2245 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2246 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2247 int rc; 2248 u32 av; 2249 2250 if (!nnp && !nosuid) 2251 return 0; /* neither NNP nor nosuid */ 2252 2253 if (new_tsec->sid == old_tsec->sid) 2254 return 0; /* No change in credentials */ 2255 2256 /* 2257 * If the policy enables the nnp_nosuid_transition policy capability, 2258 * then we permit transitions under NNP or nosuid if the 2259 * policy allows the corresponding permission between 2260 * the old and new contexts. 2261 */ 2262 if (selinux_policycap_nnp_nosuid_transition()) { 2263 av = 0; 2264 if (nnp) 2265 av |= PROCESS2__NNP_TRANSITION; 2266 if (nosuid) 2267 av |= PROCESS2__NOSUID_TRANSITION; 2268 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2269 SECCLASS_PROCESS2, av, NULL); 2270 if (!rc) 2271 return 0; 2272 } 2273 2274 /* 2275 * We also permit NNP or nosuid transitions to bounded SIDs, 2276 * i.e. SIDs that are guaranteed to only be allowed a subset 2277 * of the permissions of the current SID. 2278 */ 2279 rc = security_bounded_transition(old_tsec->sid, 2280 new_tsec->sid); 2281 if (!rc) 2282 return 0; 2283 2284 /* 2285 * On failure, preserve the errno values for NNP vs nosuid. 2286 * NNP: Operation not permitted for caller. 2287 * nosuid: Permission denied to file. 2288 */ 2289 if (nnp) 2290 return -EPERM; 2291 return -EACCES; 2292 } 2293 2294 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2295 { 2296 const struct task_security_struct *old_tsec; 2297 struct task_security_struct *new_tsec; 2298 struct inode_security_struct *isec; 2299 struct common_audit_data ad; 2300 struct inode *inode = file_inode(bprm->file); 2301 int rc; 2302 2303 /* SELinux context only depends on initial program or script and not 2304 * the script interpreter */ 2305 2306 old_tsec = selinux_cred(current_cred()); 2307 new_tsec = selinux_cred(bprm->cred); 2308 isec = inode_security(inode); 2309 2310 /* Default to the current task SID. */ 2311 new_tsec->sid = old_tsec->sid; 2312 new_tsec->osid = old_tsec->sid; 2313 2314 /* Reset fs, key, and sock SIDs on execve. */ 2315 new_tsec->create_sid = 0; 2316 new_tsec->keycreate_sid = 0; 2317 new_tsec->sockcreate_sid = 0; 2318 2319 if (old_tsec->exec_sid) { 2320 new_tsec->sid = old_tsec->exec_sid; 2321 /* Reset exec SID on execve. */ 2322 new_tsec->exec_sid = 0; 2323 2324 /* Fail on NNP or nosuid if not an allowed transition. */ 2325 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2326 if (rc) 2327 return rc; 2328 } else { 2329 /* Check for a default transition on this program. */ 2330 rc = security_transition_sid(old_tsec->sid, 2331 isec->sid, SECCLASS_PROCESS, NULL, 2332 &new_tsec->sid); 2333 if (rc) 2334 return rc; 2335 2336 /* 2337 * Fallback to old SID on NNP or nosuid if not an allowed 2338 * transition. 2339 */ 2340 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2341 if (rc) 2342 new_tsec->sid = old_tsec->sid; 2343 } 2344 2345 ad.type = LSM_AUDIT_DATA_FILE; 2346 ad.u.file = bprm->file; 2347 2348 if (new_tsec->sid == old_tsec->sid) { 2349 rc = avc_has_perm(old_tsec->sid, isec->sid, 2350 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2351 if (rc) 2352 return rc; 2353 } else { 2354 /* Check permissions for the transition. */ 2355 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2356 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2357 if (rc) 2358 return rc; 2359 2360 rc = avc_has_perm(new_tsec->sid, isec->sid, 2361 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2362 if (rc) 2363 return rc; 2364 2365 /* Check for shared state */ 2366 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2367 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2368 SECCLASS_PROCESS, PROCESS__SHARE, 2369 NULL); 2370 if (rc) 2371 return -EPERM; 2372 } 2373 2374 /* Make sure that anyone attempting to ptrace over a task that 2375 * changes its SID has the appropriate permit */ 2376 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2377 u32 ptsid = ptrace_parent_sid(); 2378 if (ptsid != 0) { 2379 rc = avc_has_perm(ptsid, new_tsec->sid, 2380 SECCLASS_PROCESS, 2381 PROCESS__PTRACE, NULL); 2382 if (rc) 2383 return -EPERM; 2384 } 2385 } 2386 2387 /* Clear any possibly unsafe personality bits on exec: */ 2388 bprm->per_clear |= PER_CLEAR_ON_SETID; 2389 2390 /* Enable secure mode for SIDs transitions unless 2391 the noatsecure permission is granted between 2392 the two SIDs, i.e. ahp returns 0. */ 2393 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2394 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2395 NULL); 2396 bprm->secureexec |= !!rc; 2397 } 2398 2399 return 0; 2400 } 2401 2402 static int match_file(const void *p, struct file *file, unsigned fd) 2403 { 2404 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2405 } 2406 2407 /* Derived from fs/exec.c:flush_old_files. */ 2408 static inline void flush_unauthorized_files(const struct cred *cred, 2409 struct files_struct *files) 2410 { 2411 struct file *file, *devnull = NULL; 2412 struct tty_struct *tty; 2413 int drop_tty = 0; 2414 unsigned n; 2415 2416 tty = get_current_tty(); 2417 if (tty) { 2418 spin_lock(&tty->files_lock); 2419 if (!list_empty(&tty->tty_files)) { 2420 struct tty_file_private *file_priv; 2421 2422 /* Revalidate access to controlling tty. 2423 Use file_path_has_perm on the tty path directly 2424 rather than using file_has_perm, as this particular 2425 open file may belong to another process and we are 2426 only interested in the inode-based check here. */ 2427 file_priv = list_first_entry(&tty->tty_files, 2428 struct tty_file_private, list); 2429 file = file_priv->file; 2430 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2431 drop_tty = 1; 2432 } 2433 spin_unlock(&tty->files_lock); 2434 tty_kref_put(tty); 2435 } 2436 /* Reset controlling tty. */ 2437 if (drop_tty) 2438 no_tty(); 2439 2440 /* Revalidate access to inherited open files. */ 2441 n = iterate_fd(files, 0, match_file, cred); 2442 if (!n) /* none found? */ 2443 return; 2444 2445 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2446 if (IS_ERR(devnull)) 2447 devnull = NULL; 2448 /* replace all the matching ones with this */ 2449 do { 2450 replace_fd(n - 1, devnull, 0); 2451 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2452 if (devnull) 2453 fput(devnull); 2454 } 2455 2456 /* 2457 * Prepare a process for imminent new credential changes due to exec 2458 */ 2459 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) 2460 { 2461 struct task_security_struct *new_tsec; 2462 struct rlimit *rlim, *initrlim; 2463 int rc, i; 2464 2465 new_tsec = selinux_cred(bprm->cred); 2466 if (new_tsec->sid == new_tsec->osid) 2467 return; 2468 2469 /* Close files for which the new task SID is not authorized. */ 2470 flush_unauthorized_files(bprm->cred, current->files); 2471 2472 /* Always clear parent death signal on SID transitions. */ 2473 current->pdeath_signal = 0; 2474 2475 /* Check whether the new SID can inherit resource limits from the old 2476 * SID. If not, reset all soft limits to the lower of the current 2477 * task's hard limit and the init task's soft limit. 2478 * 2479 * Note that the setting of hard limits (even to lower them) can be 2480 * controlled by the setrlimit check. The inclusion of the init task's 2481 * soft limit into the computation is to avoid resetting soft limits 2482 * higher than the default soft limit for cases where the default is 2483 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2484 */ 2485 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2486 PROCESS__RLIMITINH, NULL); 2487 if (rc) { 2488 /* protect against do_prlimit() */ 2489 task_lock(current); 2490 for (i = 0; i < RLIM_NLIMITS; i++) { 2491 rlim = current->signal->rlim + i; 2492 initrlim = init_task.signal->rlim + i; 2493 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2494 } 2495 task_unlock(current); 2496 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2497 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2498 } 2499 } 2500 2501 /* 2502 * Clean up the process immediately after the installation of new credentials 2503 * due to exec 2504 */ 2505 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) 2506 { 2507 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2508 u32 osid, sid; 2509 int rc; 2510 2511 osid = tsec->osid; 2512 sid = tsec->sid; 2513 2514 if (sid == osid) 2515 return; 2516 2517 /* Check whether the new SID can inherit signal state from the old SID. 2518 * If not, clear itimers to avoid subsequent signal generation and 2519 * flush and unblock signals. 2520 * 2521 * This must occur _after_ the task SID has been updated so that any 2522 * kill done after the flush will be checked against the new SID. 2523 */ 2524 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2525 if (rc) { 2526 clear_itimer(); 2527 2528 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); 2529 if (!fatal_signal_pending(current)) { 2530 flush_sigqueue(¤t->pending); 2531 flush_sigqueue(¤t->signal->shared_pending); 2532 flush_signal_handlers(current, 1); 2533 sigemptyset(¤t->blocked); 2534 recalc_sigpending(); 2535 } 2536 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); 2537 } 2538 2539 /* Wake up the parent if it is waiting so that it can recheck 2540 * wait permission to the new task SID. */ 2541 read_lock(&tasklist_lock); 2542 __wake_up_parent(current, unrcu_pointer(current->real_parent)); 2543 read_unlock(&tasklist_lock); 2544 } 2545 2546 /* superblock security operations */ 2547 2548 static int selinux_sb_alloc_security(struct super_block *sb) 2549 { 2550 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2551 2552 mutex_init(&sbsec->lock); 2553 INIT_LIST_HEAD(&sbsec->isec_head); 2554 spin_lock_init(&sbsec->isec_lock); 2555 sbsec->sid = SECINITSID_UNLABELED; 2556 sbsec->def_sid = SECINITSID_FILE; 2557 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2558 2559 return 0; 2560 } 2561 2562 static inline int opt_len(const char *s) 2563 { 2564 bool open_quote = false; 2565 int len; 2566 char c; 2567 2568 for (len = 0; (c = s[len]) != '\0'; len++) { 2569 if (c == '"') 2570 open_quote = !open_quote; 2571 if (c == ',' && !open_quote) 2572 break; 2573 } 2574 return len; 2575 } 2576 2577 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2578 { 2579 char *from = options; 2580 char *to = options; 2581 bool first = true; 2582 int rc; 2583 2584 while (1) { 2585 int len = opt_len(from); 2586 int token; 2587 char *arg = NULL; 2588 2589 token = match_opt_prefix(from, len, &arg); 2590 2591 if (token != Opt_error) { 2592 char *p, *q; 2593 2594 /* strip quotes */ 2595 if (arg) { 2596 for (p = q = arg; p < from + len; p++) { 2597 char c = *p; 2598 if (c != '"') 2599 *q++ = c; 2600 } 2601 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2602 if (!arg) { 2603 rc = -ENOMEM; 2604 goto free_opt; 2605 } 2606 } 2607 rc = selinux_add_opt(token, arg, mnt_opts); 2608 kfree(arg); 2609 arg = NULL; 2610 if (unlikely(rc)) { 2611 goto free_opt; 2612 } 2613 } else { 2614 if (!first) { // copy with preceding comma 2615 from--; 2616 len++; 2617 } 2618 if (to != from) 2619 memmove(to, from, len); 2620 to += len; 2621 first = false; 2622 } 2623 if (!from[len]) 2624 break; 2625 from += len + 1; 2626 } 2627 *to = '\0'; 2628 return 0; 2629 2630 free_opt: 2631 if (*mnt_opts) { 2632 selinux_free_mnt_opts(*mnt_opts); 2633 *mnt_opts = NULL; 2634 } 2635 return rc; 2636 } 2637 2638 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2639 { 2640 struct selinux_mnt_opts *opts = mnt_opts; 2641 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2642 2643 /* 2644 * Superblock not initialized (i.e. no options) - reject if any 2645 * options specified, otherwise accept. 2646 */ 2647 if (!(sbsec->flags & SE_SBINITIALIZED)) 2648 return opts ? 1 : 0; 2649 2650 /* 2651 * Superblock initialized and no options specified - reject if 2652 * superblock has any options set, otherwise accept. 2653 */ 2654 if (!opts) 2655 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2656 2657 if (opts->fscontext_sid) { 2658 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2659 opts->fscontext_sid)) 2660 return 1; 2661 } 2662 if (opts->context_sid) { 2663 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2664 opts->context_sid)) 2665 return 1; 2666 } 2667 if (opts->rootcontext_sid) { 2668 struct inode_security_struct *root_isec; 2669 2670 root_isec = backing_inode_security(sb->s_root); 2671 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2672 opts->rootcontext_sid)) 2673 return 1; 2674 } 2675 if (opts->defcontext_sid) { 2676 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2677 opts->defcontext_sid)) 2678 return 1; 2679 } 2680 return 0; 2681 } 2682 2683 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2684 { 2685 struct selinux_mnt_opts *opts = mnt_opts; 2686 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2687 2688 if (!(sbsec->flags & SE_SBINITIALIZED)) 2689 return 0; 2690 2691 if (!opts) 2692 return 0; 2693 2694 if (opts->fscontext_sid) { 2695 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2696 opts->fscontext_sid)) 2697 goto out_bad_option; 2698 } 2699 if (opts->context_sid) { 2700 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2701 opts->context_sid)) 2702 goto out_bad_option; 2703 } 2704 if (opts->rootcontext_sid) { 2705 struct inode_security_struct *root_isec; 2706 root_isec = backing_inode_security(sb->s_root); 2707 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2708 opts->rootcontext_sid)) 2709 goto out_bad_option; 2710 } 2711 if (opts->defcontext_sid) { 2712 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2713 opts->defcontext_sid)) 2714 goto out_bad_option; 2715 } 2716 return 0; 2717 2718 out_bad_option: 2719 pr_warn("SELinux: unable to change security options " 2720 "during remount (dev %s, type=%s)\n", sb->s_id, 2721 sb->s_type->name); 2722 return -EINVAL; 2723 } 2724 2725 static int selinux_sb_kern_mount(const struct super_block *sb) 2726 { 2727 const struct cred *cred = current_cred(); 2728 struct common_audit_data ad; 2729 2730 ad.type = LSM_AUDIT_DATA_DENTRY; 2731 ad.u.dentry = sb->s_root; 2732 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2733 } 2734 2735 static int selinux_sb_statfs(struct dentry *dentry) 2736 { 2737 const struct cred *cred = current_cred(); 2738 struct common_audit_data ad; 2739 2740 ad.type = LSM_AUDIT_DATA_DENTRY; 2741 ad.u.dentry = dentry->d_sb->s_root; 2742 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2743 } 2744 2745 static int selinux_mount(const char *dev_name, 2746 const struct path *path, 2747 const char *type, 2748 unsigned long flags, 2749 void *data) 2750 { 2751 const struct cred *cred = current_cred(); 2752 2753 if (flags & MS_REMOUNT) 2754 return superblock_has_perm(cred, path->dentry->d_sb, 2755 FILESYSTEM__REMOUNT, NULL); 2756 else 2757 return path_has_perm(cred, path, FILE__MOUNTON); 2758 } 2759 2760 static int selinux_move_mount(const struct path *from_path, 2761 const struct path *to_path) 2762 { 2763 const struct cred *cred = current_cred(); 2764 2765 return path_has_perm(cred, to_path, FILE__MOUNTON); 2766 } 2767 2768 static int selinux_umount(struct vfsmount *mnt, int flags) 2769 { 2770 const struct cred *cred = current_cred(); 2771 2772 return superblock_has_perm(cred, mnt->mnt_sb, 2773 FILESYSTEM__UNMOUNT, NULL); 2774 } 2775 2776 static int selinux_fs_context_submount(struct fs_context *fc, 2777 struct super_block *reference) 2778 { 2779 const struct superblock_security_struct *sbsec = selinux_superblock(reference); 2780 struct selinux_mnt_opts *opts; 2781 2782 /* 2783 * Ensure that fc->security remains NULL when no options are set 2784 * as expected by selinux_set_mnt_opts(). 2785 */ 2786 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) 2787 return 0; 2788 2789 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 2790 if (!opts) 2791 return -ENOMEM; 2792 2793 if (sbsec->flags & FSCONTEXT_MNT) 2794 opts->fscontext_sid = sbsec->sid; 2795 if (sbsec->flags & CONTEXT_MNT) 2796 opts->context_sid = sbsec->mntpoint_sid; 2797 if (sbsec->flags & DEFCONTEXT_MNT) 2798 opts->defcontext_sid = sbsec->def_sid; 2799 fc->security = opts; 2800 return 0; 2801 } 2802 2803 static int selinux_fs_context_dup(struct fs_context *fc, 2804 struct fs_context *src_fc) 2805 { 2806 const struct selinux_mnt_opts *src = src_fc->security; 2807 2808 if (!src) 2809 return 0; 2810 2811 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); 2812 return fc->security ? 0 : -ENOMEM; 2813 } 2814 2815 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2816 fsparam_string(CONTEXT_STR, Opt_context), 2817 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2818 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2819 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2820 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2821 {} 2822 }; 2823 2824 static int selinux_fs_context_parse_param(struct fs_context *fc, 2825 struct fs_parameter *param) 2826 { 2827 struct fs_parse_result result; 2828 int opt; 2829 2830 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2831 if (opt < 0) 2832 return opt; 2833 2834 return selinux_add_opt(opt, param->string, &fc->security); 2835 } 2836 2837 /* inode security operations */ 2838 2839 static int selinux_inode_alloc_security(struct inode *inode) 2840 { 2841 struct inode_security_struct *isec = selinux_inode(inode); 2842 u32 sid = current_sid(); 2843 2844 spin_lock_init(&isec->lock); 2845 INIT_LIST_HEAD(&isec->list); 2846 isec->inode = inode; 2847 isec->sid = SECINITSID_UNLABELED; 2848 isec->sclass = SECCLASS_FILE; 2849 isec->task_sid = sid; 2850 isec->initialized = LABEL_INVALID; 2851 2852 return 0; 2853 } 2854 2855 static void selinux_inode_free_security(struct inode *inode) 2856 { 2857 inode_free_security(inode); 2858 } 2859 2860 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2861 const struct qstr *name, 2862 const char **xattr_name, void **ctx, 2863 u32 *ctxlen) 2864 { 2865 u32 newsid; 2866 int rc; 2867 2868 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2869 d_inode(dentry->d_parent), name, 2870 inode_mode_to_security_class(mode), 2871 &newsid); 2872 if (rc) 2873 return rc; 2874 2875 if (xattr_name) 2876 *xattr_name = XATTR_NAME_SELINUX; 2877 2878 return security_sid_to_context(newsid, (char **)ctx, 2879 ctxlen); 2880 } 2881 2882 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2883 struct qstr *name, 2884 const struct cred *old, 2885 struct cred *new) 2886 { 2887 u32 newsid; 2888 int rc; 2889 struct task_security_struct *tsec; 2890 2891 rc = selinux_determine_inode_label(selinux_cred(old), 2892 d_inode(dentry->d_parent), name, 2893 inode_mode_to_security_class(mode), 2894 &newsid); 2895 if (rc) 2896 return rc; 2897 2898 tsec = selinux_cred(new); 2899 tsec->create_sid = newsid; 2900 return 0; 2901 } 2902 2903 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2904 const struct qstr *qstr, 2905 struct xattr *xattrs, int *xattr_count) 2906 { 2907 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2908 struct superblock_security_struct *sbsec; 2909 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); 2910 u32 newsid, clen; 2911 int rc; 2912 char *context; 2913 2914 sbsec = selinux_superblock(dir->i_sb); 2915 2916 newsid = tsec->create_sid; 2917 2918 rc = selinux_determine_inode_label(tsec, dir, qstr, 2919 inode_mode_to_security_class(inode->i_mode), 2920 &newsid); 2921 if (rc) 2922 return rc; 2923 2924 /* Possibly defer initialization to selinux_complete_init. */ 2925 if (sbsec->flags & SE_SBINITIALIZED) { 2926 struct inode_security_struct *isec = selinux_inode(inode); 2927 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2928 isec->sid = newsid; 2929 isec->initialized = LABEL_INITIALIZED; 2930 } 2931 2932 if (!selinux_initialized() || 2933 !(sbsec->flags & SBLABEL_MNT)) 2934 return -EOPNOTSUPP; 2935 2936 if (xattr) { 2937 rc = security_sid_to_context_force(newsid, 2938 &context, &clen); 2939 if (rc) 2940 return rc; 2941 xattr->value = context; 2942 xattr->value_len = clen; 2943 xattr->name = XATTR_SELINUX_SUFFIX; 2944 } 2945 2946 return 0; 2947 } 2948 2949 static int selinux_inode_init_security_anon(struct inode *inode, 2950 const struct qstr *name, 2951 const struct inode *context_inode) 2952 { 2953 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2954 struct common_audit_data ad; 2955 struct inode_security_struct *isec; 2956 int rc; 2957 2958 if (unlikely(!selinux_initialized())) 2959 return 0; 2960 2961 isec = selinux_inode(inode); 2962 2963 /* 2964 * We only get here once per ephemeral inode. The inode has 2965 * been initialized via inode_alloc_security but is otherwise 2966 * untouched. 2967 */ 2968 2969 if (context_inode) { 2970 struct inode_security_struct *context_isec = 2971 selinux_inode(context_inode); 2972 if (context_isec->initialized != LABEL_INITIALIZED) { 2973 pr_err("SELinux: context_inode is not initialized\n"); 2974 return -EACCES; 2975 } 2976 2977 isec->sclass = context_isec->sclass; 2978 isec->sid = context_isec->sid; 2979 } else { 2980 isec->sclass = SECCLASS_ANON_INODE; 2981 rc = security_transition_sid( 2982 tsec->sid, tsec->sid, 2983 isec->sclass, name, &isec->sid); 2984 if (rc) 2985 return rc; 2986 } 2987 2988 isec->initialized = LABEL_INITIALIZED; 2989 /* 2990 * Now that we've initialized security, check whether we're 2991 * allowed to actually create this type of anonymous inode. 2992 */ 2993 2994 ad.type = LSM_AUDIT_DATA_ANONINODE; 2995 ad.u.anonclass = name ? (const char *)name->name : "?"; 2996 2997 return avc_has_perm(tsec->sid, 2998 isec->sid, 2999 isec->sclass, 3000 FILE__CREATE, 3001 &ad); 3002 } 3003 3004 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3005 { 3006 return may_create(dir, dentry, SECCLASS_FILE); 3007 } 3008 3009 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3010 { 3011 return may_link(dir, old_dentry, MAY_LINK); 3012 } 3013 3014 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3015 { 3016 return may_link(dir, dentry, MAY_UNLINK); 3017 } 3018 3019 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3020 { 3021 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3022 } 3023 3024 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3025 { 3026 return may_create(dir, dentry, SECCLASS_DIR); 3027 } 3028 3029 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3030 { 3031 return may_link(dir, dentry, MAY_RMDIR); 3032 } 3033 3034 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3035 { 3036 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3037 } 3038 3039 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3040 struct inode *new_inode, struct dentry *new_dentry) 3041 { 3042 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3043 } 3044 3045 static int selinux_inode_readlink(struct dentry *dentry) 3046 { 3047 const struct cred *cred = current_cred(); 3048 3049 return dentry_has_perm(cred, dentry, FILE__READ); 3050 } 3051 3052 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3053 bool rcu) 3054 { 3055 const struct cred *cred = current_cred(); 3056 struct common_audit_data ad; 3057 struct inode_security_struct *isec; 3058 u32 sid; 3059 3060 validate_creds(cred); 3061 3062 ad.type = LSM_AUDIT_DATA_DENTRY; 3063 ad.u.dentry = dentry; 3064 sid = cred_sid(cred); 3065 isec = inode_security_rcu(inode, rcu); 3066 if (IS_ERR(isec)) 3067 return PTR_ERR(isec); 3068 3069 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); 3070 } 3071 3072 static noinline int audit_inode_permission(struct inode *inode, 3073 u32 perms, u32 audited, u32 denied, 3074 int result) 3075 { 3076 struct common_audit_data ad; 3077 struct inode_security_struct *isec = selinux_inode(inode); 3078 3079 ad.type = LSM_AUDIT_DATA_INODE; 3080 ad.u.inode = inode; 3081 3082 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3083 audited, denied, result, &ad); 3084 } 3085 3086 static int selinux_inode_permission(struct inode *inode, int mask) 3087 { 3088 const struct cred *cred = current_cred(); 3089 u32 perms; 3090 bool from_access; 3091 bool no_block = mask & MAY_NOT_BLOCK; 3092 struct inode_security_struct *isec; 3093 u32 sid; 3094 struct av_decision avd; 3095 int rc, rc2; 3096 u32 audited, denied; 3097 3098 from_access = mask & MAY_ACCESS; 3099 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3100 3101 /* No permission to check. Existence test. */ 3102 if (!mask) 3103 return 0; 3104 3105 validate_creds(cred); 3106 3107 if (unlikely(IS_PRIVATE(inode))) 3108 return 0; 3109 3110 perms = file_mask_to_av(inode->i_mode, mask); 3111 3112 sid = cred_sid(cred); 3113 isec = inode_security_rcu(inode, no_block); 3114 if (IS_ERR(isec)) 3115 return PTR_ERR(isec); 3116 3117 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, 3118 &avd); 3119 audited = avc_audit_required(perms, &avd, rc, 3120 from_access ? FILE__AUDIT_ACCESS : 0, 3121 &denied); 3122 if (likely(!audited)) 3123 return rc; 3124 3125 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3126 if (rc2) 3127 return rc2; 3128 return rc; 3129 } 3130 3131 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3132 { 3133 const struct cred *cred = current_cred(); 3134 struct inode *inode = d_backing_inode(dentry); 3135 unsigned int ia_valid = iattr->ia_valid; 3136 __u32 av = FILE__WRITE; 3137 3138 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3139 if (ia_valid & ATTR_FORCE) { 3140 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3141 ATTR_FORCE); 3142 if (!ia_valid) 3143 return 0; 3144 } 3145 3146 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3147 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3148 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3149 3150 if (selinux_policycap_openperm() && 3151 inode->i_sb->s_magic != SOCKFS_MAGIC && 3152 (ia_valid & ATTR_SIZE) && 3153 !(ia_valid & ATTR_FILE)) 3154 av |= FILE__OPEN; 3155 3156 return dentry_has_perm(cred, dentry, av); 3157 } 3158 3159 static int selinux_inode_getattr(const struct path *path) 3160 { 3161 return path_has_perm(current_cred(), path, FILE__GETATTR); 3162 } 3163 3164 static bool has_cap_mac_admin(bool audit) 3165 { 3166 const struct cred *cred = current_cred(); 3167 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3168 3169 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3170 return false; 3171 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3172 return false; 3173 return true; 3174 } 3175 3176 static int selinux_inode_setxattr(struct mnt_idmap *idmap, 3177 struct dentry *dentry, const char *name, 3178 const void *value, size_t size, int flags) 3179 { 3180 struct inode *inode = d_backing_inode(dentry); 3181 struct inode_security_struct *isec; 3182 struct superblock_security_struct *sbsec; 3183 struct common_audit_data ad; 3184 u32 newsid, sid = current_sid(); 3185 int rc = 0; 3186 3187 if (strcmp(name, XATTR_NAME_SELINUX)) { 3188 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3189 if (rc) 3190 return rc; 3191 3192 /* Not an attribute we recognize, so just check the 3193 ordinary setattr permission. */ 3194 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3195 } 3196 3197 if (!selinux_initialized()) 3198 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); 3199 3200 sbsec = selinux_superblock(inode->i_sb); 3201 if (!(sbsec->flags & SBLABEL_MNT)) 3202 return -EOPNOTSUPP; 3203 3204 if (!inode_owner_or_capable(idmap, inode)) 3205 return -EPERM; 3206 3207 ad.type = LSM_AUDIT_DATA_DENTRY; 3208 ad.u.dentry = dentry; 3209 3210 isec = backing_inode_security(dentry); 3211 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3212 FILE__RELABELFROM, &ad); 3213 if (rc) 3214 return rc; 3215 3216 rc = security_context_to_sid(value, size, &newsid, 3217 GFP_KERNEL); 3218 if (rc == -EINVAL) { 3219 if (!has_cap_mac_admin(true)) { 3220 struct audit_buffer *ab; 3221 size_t audit_size; 3222 3223 /* We strip a nul only if it is at the end, otherwise the 3224 * context contains a nul and we should audit that */ 3225 if (value) { 3226 const char *str = value; 3227 3228 if (str[size - 1] == '\0') 3229 audit_size = size - 1; 3230 else 3231 audit_size = size; 3232 } else { 3233 audit_size = 0; 3234 } 3235 ab = audit_log_start(audit_context(), 3236 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3237 if (!ab) 3238 return rc; 3239 audit_log_format(ab, "op=setxattr invalid_context="); 3240 audit_log_n_untrustedstring(ab, value, audit_size); 3241 audit_log_end(ab); 3242 3243 return rc; 3244 } 3245 rc = security_context_to_sid_force(value, 3246 size, &newsid); 3247 } 3248 if (rc) 3249 return rc; 3250 3251 rc = avc_has_perm(sid, newsid, isec->sclass, 3252 FILE__RELABELTO, &ad); 3253 if (rc) 3254 return rc; 3255 3256 rc = security_validate_transition(isec->sid, newsid, 3257 sid, isec->sclass); 3258 if (rc) 3259 return rc; 3260 3261 return avc_has_perm(newsid, 3262 sbsec->sid, 3263 SECCLASS_FILESYSTEM, 3264 FILESYSTEM__ASSOCIATE, 3265 &ad); 3266 } 3267 3268 static int selinux_inode_set_acl(struct mnt_idmap *idmap, 3269 struct dentry *dentry, const char *acl_name, 3270 struct posix_acl *kacl) 3271 { 3272 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3273 } 3274 3275 static int selinux_inode_get_acl(struct mnt_idmap *idmap, 3276 struct dentry *dentry, const char *acl_name) 3277 { 3278 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); 3279 } 3280 3281 static int selinux_inode_remove_acl(struct mnt_idmap *idmap, 3282 struct dentry *dentry, const char *acl_name) 3283 { 3284 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3285 } 3286 3287 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3288 const void *value, size_t size, 3289 int flags) 3290 { 3291 struct inode *inode = d_backing_inode(dentry); 3292 struct inode_security_struct *isec; 3293 u32 newsid; 3294 int rc; 3295 3296 if (strcmp(name, XATTR_NAME_SELINUX)) { 3297 /* Not an attribute we recognize, so nothing to do. */ 3298 return; 3299 } 3300 3301 if (!selinux_initialized()) { 3302 /* If we haven't even been initialized, then we can't validate 3303 * against a policy, so leave the label as invalid. It may 3304 * resolve to a valid label on the next revalidation try if 3305 * we've since initialized. 3306 */ 3307 return; 3308 } 3309 3310 rc = security_context_to_sid_force(value, size, 3311 &newsid); 3312 if (rc) { 3313 pr_err("SELinux: unable to map context to SID" 3314 "for (%s, %lu), rc=%d\n", 3315 inode->i_sb->s_id, inode->i_ino, -rc); 3316 return; 3317 } 3318 3319 isec = backing_inode_security(dentry); 3320 spin_lock(&isec->lock); 3321 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3322 isec->sid = newsid; 3323 isec->initialized = LABEL_INITIALIZED; 3324 spin_unlock(&isec->lock); 3325 } 3326 3327 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3328 { 3329 const struct cred *cred = current_cred(); 3330 3331 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3332 } 3333 3334 static int selinux_inode_listxattr(struct dentry *dentry) 3335 { 3336 const struct cred *cred = current_cred(); 3337 3338 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3339 } 3340 3341 static int selinux_inode_removexattr(struct mnt_idmap *idmap, 3342 struct dentry *dentry, const char *name) 3343 { 3344 if (strcmp(name, XATTR_NAME_SELINUX)) { 3345 int rc = cap_inode_removexattr(idmap, dentry, name); 3346 if (rc) 3347 return rc; 3348 3349 /* Not an attribute we recognize, so just check the 3350 ordinary setattr permission. */ 3351 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3352 } 3353 3354 if (!selinux_initialized()) 3355 return 0; 3356 3357 /* No one is allowed to remove a SELinux security label. 3358 You can change the label, but all data must be labeled. */ 3359 return -EACCES; 3360 } 3361 3362 static int selinux_path_notify(const struct path *path, u64 mask, 3363 unsigned int obj_type) 3364 { 3365 int ret; 3366 u32 perm; 3367 3368 struct common_audit_data ad; 3369 3370 ad.type = LSM_AUDIT_DATA_PATH; 3371 ad.u.path = *path; 3372 3373 /* 3374 * Set permission needed based on the type of mark being set. 3375 * Performs an additional check for sb watches. 3376 */ 3377 switch (obj_type) { 3378 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3379 perm = FILE__WATCH_MOUNT; 3380 break; 3381 case FSNOTIFY_OBJ_TYPE_SB: 3382 perm = FILE__WATCH_SB; 3383 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3384 FILESYSTEM__WATCH, &ad); 3385 if (ret) 3386 return ret; 3387 break; 3388 case FSNOTIFY_OBJ_TYPE_INODE: 3389 perm = FILE__WATCH; 3390 break; 3391 default: 3392 return -EINVAL; 3393 } 3394 3395 /* blocking watches require the file:watch_with_perm permission */ 3396 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3397 perm |= FILE__WATCH_WITH_PERM; 3398 3399 /* watches on read-like events need the file:watch_reads permission */ 3400 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3401 perm |= FILE__WATCH_READS; 3402 3403 return path_has_perm(current_cred(), path, perm); 3404 } 3405 3406 /* 3407 * Copy the inode security context value to the user. 3408 * 3409 * Permission check is handled by selinux_inode_getxattr hook. 3410 */ 3411 static int selinux_inode_getsecurity(struct mnt_idmap *idmap, 3412 struct inode *inode, const char *name, 3413 void **buffer, bool alloc) 3414 { 3415 u32 size; 3416 int error; 3417 char *context = NULL; 3418 struct inode_security_struct *isec; 3419 3420 /* 3421 * If we're not initialized yet, then we can't validate contexts, so 3422 * just let vfs_getxattr fall back to using the on-disk xattr. 3423 */ 3424 if (!selinux_initialized() || 3425 strcmp(name, XATTR_SELINUX_SUFFIX)) 3426 return -EOPNOTSUPP; 3427 3428 /* 3429 * If the caller has CAP_MAC_ADMIN, then get the raw context 3430 * value even if it is not defined by current policy; otherwise, 3431 * use the in-core value under current policy. 3432 * Use the non-auditing forms of the permission checks since 3433 * getxattr may be called by unprivileged processes commonly 3434 * and lack of permission just means that we fall back to the 3435 * in-core context value, not a denial. 3436 */ 3437 isec = inode_security(inode); 3438 if (has_cap_mac_admin(false)) 3439 error = security_sid_to_context_force(isec->sid, &context, 3440 &size); 3441 else 3442 error = security_sid_to_context(isec->sid, 3443 &context, &size); 3444 if (error) 3445 return error; 3446 error = size; 3447 if (alloc) { 3448 *buffer = context; 3449 goto out_nofree; 3450 } 3451 kfree(context); 3452 out_nofree: 3453 return error; 3454 } 3455 3456 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3457 const void *value, size_t size, int flags) 3458 { 3459 struct inode_security_struct *isec = inode_security_novalidate(inode); 3460 struct superblock_security_struct *sbsec; 3461 u32 newsid; 3462 int rc; 3463 3464 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3465 return -EOPNOTSUPP; 3466 3467 sbsec = selinux_superblock(inode->i_sb); 3468 if (!(sbsec->flags & SBLABEL_MNT)) 3469 return -EOPNOTSUPP; 3470 3471 if (!value || !size) 3472 return -EACCES; 3473 3474 rc = security_context_to_sid(value, size, &newsid, 3475 GFP_KERNEL); 3476 if (rc) 3477 return rc; 3478 3479 spin_lock(&isec->lock); 3480 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3481 isec->sid = newsid; 3482 isec->initialized = LABEL_INITIALIZED; 3483 spin_unlock(&isec->lock); 3484 return 0; 3485 } 3486 3487 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3488 { 3489 const int len = sizeof(XATTR_NAME_SELINUX); 3490 3491 if (!selinux_initialized()) 3492 return 0; 3493 3494 if (buffer && len <= buffer_size) 3495 memcpy(buffer, XATTR_NAME_SELINUX, len); 3496 return len; 3497 } 3498 3499 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3500 { 3501 struct inode_security_struct *isec = inode_security_novalidate(inode); 3502 *secid = isec->sid; 3503 } 3504 3505 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3506 { 3507 u32 sid; 3508 struct task_security_struct *tsec; 3509 struct cred *new_creds = *new; 3510 3511 if (new_creds == NULL) { 3512 new_creds = prepare_creds(); 3513 if (!new_creds) 3514 return -ENOMEM; 3515 } 3516 3517 tsec = selinux_cred(new_creds); 3518 /* Get label from overlay inode and set it in create_sid */ 3519 selinux_inode_getsecid(d_inode(src), &sid); 3520 tsec->create_sid = sid; 3521 *new = new_creds; 3522 return 0; 3523 } 3524 3525 static int selinux_inode_copy_up_xattr(const char *name) 3526 { 3527 /* The copy_up hook above sets the initial context on an inode, but we 3528 * don't then want to overwrite it by blindly copying all the lower 3529 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3530 */ 3531 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3532 return 1; /* Discard */ 3533 /* 3534 * Any other attribute apart from SELINUX is not claimed, supported 3535 * by selinux. 3536 */ 3537 return -EOPNOTSUPP; 3538 } 3539 3540 /* kernfs node operations */ 3541 3542 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3543 struct kernfs_node *kn) 3544 { 3545 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3546 u32 parent_sid, newsid, clen; 3547 int rc; 3548 char *context; 3549 3550 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3551 if (rc == -ENODATA) 3552 return 0; 3553 else if (rc < 0) 3554 return rc; 3555 3556 clen = (u32)rc; 3557 context = kmalloc(clen, GFP_KERNEL); 3558 if (!context) 3559 return -ENOMEM; 3560 3561 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3562 if (rc < 0) { 3563 kfree(context); 3564 return rc; 3565 } 3566 3567 rc = security_context_to_sid(context, clen, &parent_sid, 3568 GFP_KERNEL); 3569 kfree(context); 3570 if (rc) 3571 return rc; 3572 3573 if (tsec->create_sid) { 3574 newsid = tsec->create_sid; 3575 } else { 3576 u16 secclass = inode_mode_to_security_class(kn->mode); 3577 struct qstr q; 3578 3579 q.name = kn->name; 3580 q.hash_len = hashlen_string(kn_dir, kn->name); 3581 3582 rc = security_transition_sid(tsec->sid, 3583 parent_sid, secclass, &q, 3584 &newsid); 3585 if (rc) 3586 return rc; 3587 } 3588 3589 rc = security_sid_to_context_force(newsid, 3590 &context, &clen); 3591 if (rc) 3592 return rc; 3593 3594 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3595 XATTR_CREATE); 3596 kfree(context); 3597 return rc; 3598 } 3599 3600 3601 /* file security operations */ 3602 3603 static int selinux_revalidate_file_permission(struct file *file, int mask) 3604 { 3605 const struct cred *cred = current_cred(); 3606 struct inode *inode = file_inode(file); 3607 3608 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3609 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3610 mask |= MAY_APPEND; 3611 3612 return file_has_perm(cred, file, 3613 file_mask_to_av(inode->i_mode, mask)); 3614 } 3615 3616 static int selinux_file_permission(struct file *file, int mask) 3617 { 3618 struct inode *inode = file_inode(file); 3619 struct file_security_struct *fsec = selinux_file(file); 3620 struct inode_security_struct *isec; 3621 u32 sid = current_sid(); 3622 3623 if (!mask) 3624 /* No permission to check. Existence test. */ 3625 return 0; 3626 3627 isec = inode_security(inode); 3628 if (sid == fsec->sid && fsec->isid == isec->sid && 3629 fsec->pseqno == avc_policy_seqno()) 3630 /* No change since file_open check. */ 3631 return 0; 3632 3633 return selinux_revalidate_file_permission(file, mask); 3634 } 3635 3636 static int selinux_file_alloc_security(struct file *file) 3637 { 3638 struct file_security_struct *fsec = selinux_file(file); 3639 u32 sid = current_sid(); 3640 3641 fsec->sid = sid; 3642 fsec->fown_sid = sid; 3643 3644 return 0; 3645 } 3646 3647 /* 3648 * Check whether a task has the ioctl permission and cmd 3649 * operation to an inode. 3650 */ 3651 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3652 u32 requested, u16 cmd) 3653 { 3654 struct common_audit_data ad; 3655 struct file_security_struct *fsec = selinux_file(file); 3656 struct inode *inode = file_inode(file); 3657 struct inode_security_struct *isec; 3658 struct lsm_ioctlop_audit ioctl; 3659 u32 ssid = cred_sid(cred); 3660 int rc; 3661 u8 driver = cmd >> 8; 3662 u8 xperm = cmd & 0xff; 3663 3664 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3665 ad.u.op = &ioctl; 3666 ad.u.op->cmd = cmd; 3667 ad.u.op->path = file->f_path; 3668 3669 if (ssid != fsec->sid) { 3670 rc = avc_has_perm(ssid, fsec->sid, 3671 SECCLASS_FD, 3672 FD__USE, 3673 &ad); 3674 if (rc) 3675 goto out; 3676 } 3677 3678 if (unlikely(IS_PRIVATE(inode))) 3679 return 0; 3680 3681 isec = inode_security(inode); 3682 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3683 requested, driver, xperm, &ad); 3684 out: 3685 return rc; 3686 } 3687 3688 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3689 unsigned long arg) 3690 { 3691 const struct cred *cred = current_cred(); 3692 int error = 0; 3693 3694 switch (cmd) { 3695 case FIONREAD: 3696 case FIBMAP: 3697 case FIGETBSZ: 3698 case FS_IOC_GETFLAGS: 3699 case FS_IOC_GETVERSION: 3700 error = file_has_perm(cred, file, FILE__GETATTR); 3701 break; 3702 3703 case FS_IOC_SETFLAGS: 3704 case FS_IOC_SETVERSION: 3705 error = file_has_perm(cred, file, FILE__SETATTR); 3706 break; 3707 3708 /* sys_ioctl() checks */ 3709 case FIONBIO: 3710 case FIOASYNC: 3711 error = file_has_perm(cred, file, 0); 3712 break; 3713 3714 case KDSKBENT: 3715 case KDSKBSENT: 3716 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3717 CAP_OPT_NONE, true); 3718 break; 3719 3720 case FIOCLEX: 3721 case FIONCLEX: 3722 if (!selinux_policycap_ioctl_skip_cloexec()) 3723 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3724 break; 3725 3726 /* default case assumes that the command will go 3727 * to the file's ioctl() function. 3728 */ 3729 default: 3730 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3731 } 3732 return error; 3733 } 3734 3735 static int default_noexec __ro_after_init; 3736 3737 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3738 { 3739 const struct cred *cred = current_cred(); 3740 u32 sid = cred_sid(cred); 3741 int rc = 0; 3742 3743 if (default_noexec && 3744 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3745 (!shared && (prot & PROT_WRITE)))) { 3746 /* 3747 * We are making executable an anonymous mapping or a 3748 * private file mapping that will also be writable. 3749 * This has an additional check. 3750 */ 3751 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3752 PROCESS__EXECMEM, NULL); 3753 if (rc) 3754 goto error; 3755 } 3756 3757 if (file) { 3758 /* read access is always possible with a mapping */ 3759 u32 av = FILE__READ; 3760 3761 /* write access only matters if the mapping is shared */ 3762 if (shared && (prot & PROT_WRITE)) 3763 av |= FILE__WRITE; 3764 3765 if (prot & PROT_EXEC) 3766 av |= FILE__EXECUTE; 3767 3768 return file_has_perm(cred, file, av); 3769 } 3770 3771 error: 3772 return rc; 3773 } 3774 3775 static int selinux_mmap_addr(unsigned long addr) 3776 { 3777 int rc = 0; 3778 3779 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3780 u32 sid = current_sid(); 3781 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3782 MEMPROTECT__MMAP_ZERO, NULL); 3783 } 3784 3785 return rc; 3786 } 3787 3788 static int selinux_mmap_file(struct file *file, 3789 unsigned long reqprot __always_unused, 3790 unsigned long prot, unsigned long flags) 3791 { 3792 struct common_audit_data ad; 3793 int rc; 3794 3795 if (file) { 3796 ad.type = LSM_AUDIT_DATA_FILE; 3797 ad.u.file = file; 3798 rc = inode_has_perm(current_cred(), file_inode(file), 3799 FILE__MAP, &ad); 3800 if (rc) 3801 return rc; 3802 } 3803 3804 return file_map_prot_check(file, prot, 3805 (flags & MAP_TYPE) == MAP_SHARED); 3806 } 3807 3808 static int selinux_file_mprotect(struct vm_area_struct *vma, 3809 unsigned long reqprot __always_unused, 3810 unsigned long prot) 3811 { 3812 const struct cred *cred = current_cred(); 3813 u32 sid = cred_sid(cred); 3814 3815 if (default_noexec && 3816 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3817 int rc = 0; 3818 if (vma_is_initial_heap(vma)) { 3819 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3820 PROCESS__EXECHEAP, NULL); 3821 } else if (!vma->vm_file && (vma_is_initial_stack(vma) || 3822 vma_is_stack_for_current(vma))) { 3823 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3824 PROCESS__EXECSTACK, NULL); 3825 } else if (vma->vm_file && vma->anon_vma) { 3826 /* 3827 * We are making executable a file mapping that has 3828 * had some COW done. Since pages might have been 3829 * written, check ability to execute the possibly 3830 * modified content. This typically should only 3831 * occur for text relocations. 3832 */ 3833 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3834 } 3835 if (rc) 3836 return rc; 3837 } 3838 3839 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3840 } 3841 3842 static int selinux_file_lock(struct file *file, unsigned int cmd) 3843 { 3844 const struct cred *cred = current_cred(); 3845 3846 return file_has_perm(cred, file, FILE__LOCK); 3847 } 3848 3849 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3850 unsigned long arg) 3851 { 3852 const struct cred *cred = current_cred(); 3853 int err = 0; 3854 3855 switch (cmd) { 3856 case F_SETFL: 3857 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3858 err = file_has_perm(cred, file, FILE__WRITE); 3859 break; 3860 } 3861 fallthrough; 3862 case F_SETOWN: 3863 case F_SETSIG: 3864 case F_GETFL: 3865 case F_GETOWN: 3866 case F_GETSIG: 3867 case F_GETOWNER_UIDS: 3868 /* Just check FD__USE permission */ 3869 err = file_has_perm(cred, file, 0); 3870 break; 3871 case F_GETLK: 3872 case F_SETLK: 3873 case F_SETLKW: 3874 case F_OFD_GETLK: 3875 case F_OFD_SETLK: 3876 case F_OFD_SETLKW: 3877 #if BITS_PER_LONG == 32 3878 case F_GETLK64: 3879 case F_SETLK64: 3880 case F_SETLKW64: 3881 #endif 3882 err = file_has_perm(cred, file, FILE__LOCK); 3883 break; 3884 } 3885 3886 return err; 3887 } 3888 3889 static void selinux_file_set_fowner(struct file *file) 3890 { 3891 struct file_security_struct *fsec; 3892 3893 fsec = selinux_file(file); 3894 fsec->fown_sid = current_sid(); 3895 } 3896 3897 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3898 struct fown_struct *fown, int signum) 3899 { 3900 struct file *file; 3901 u32 sid = task_sid_obj(tsk); 3902 u32 perm; 3903 struct file_security_struct *fsec; 3904 3905 /* struct fown_struct is never outside the context of a struct file */ 3906 file = container_of(fown, struct file, f_owner); 3907 3908 fsec = selinux_file(file); 3909 3910 if (!signum) 3911 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3912 else 3913 perm = signal_to_av(signum); 3914 3915 return avc_has_perm(fsec->fown_sid, sid, 3916 SECCLASS_PROCESS, perm, NULL); 3917 } 3918 3919 static int selinux_file_receive(struct file *file) 3920 { 3921 const struct cred *cred = current_cred(); 3922 3923 return file_has_perm(cred, file, file_to_av(file)); 3924 } 3925 3926 static int selinux_file_open(struct file *file) 3927 { 3928 struct file_security_struct *fsec; 3929 struct inode_security_struct *isec; 3930 3931 fsec = selinux_file(file); 3932 isec = inode_security(file_inode(file)); 3933 /* 3934 * Save inode label and policy sequence number 3935 * at open-time so that selinux_file_permission 3936 * can determine whether revalidation is necessary. 3937 * Task label is already saved in the file security 3938 * struct as its SID. 3939 */ 3940 fsec->isid = isec->sid; 3941 fsec->pseqno = avc_policy_seqno(); 3942 /* 3943 * Since the inode label or policy seqno may have changed 3944 * between the selinux_inode_permission check and the saving 3945 * of state above, recheck that access is still permitted. 3946 * Otherwise, access might never be revalidated against the 3947 * new inode label or new policy. 3948 * This check is not redundant - do not remove. 3949 */ 3950 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3951 } 3952 3953 /* task security operations */ 3954 3955 static int selinux_task_alloc(struct task_struct *task, 3956 unsigned long clone_flags) 3957 { 3958 u32 sid = current_sid(); 3959 3960 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3961 } 3962 3963 /* 3964 * prepare a new set of credentials for modification 3965 */ 3966 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3967 gfp_t gfp) 3968 { 3969 const struct task_security_struct *old_tsec = selinux_cred(old); 3970 struct task_security_struct *tsec = selinux_cred(new); 3971 3972 *tsec = *old_tsec; 3973 return 0; 3974 } 3975 3976 /* 3977 * transfer the SELinux data to a blank set of creds 3978 */ 3979 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 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 } 3986 3987 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 3988 { 3989 *secid = cred_sid(c); 3990 } 3991 3992 /* 3993 * set the security data for a kernel service 3994 * - all the creation contexts are set to unlabelled 3995 */ 3996 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3997 { 3998 struct task_security_struct *tsec = selinux_cred(new); 3999 u32 sid = current_sid(); 4000 int ret; 4001 4002 ret = avc_has_perm(sid, secid, 4003 SECCLASS_KERNEL_SERVICE, 4004 KERNEL_SERVICE__USE_AS_OVERRIDE, 4005 NULL); 4006 if (ret == 0) { 4007 tsec->sid = secid; 4008 tsec->create_sid = 0; 4009 tsec->keycreate_sid = 0; 4010 tsec->sockcreate_sid = 0; 4011 } 4012 return ret; 4013 } 4014 4015 /* 4016 * set the file creation context in a security record to the same as the 4017 * objective context of the specified inode 4018 */ 4019 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4020 { 4021 struct inode_security_struct *isec = inode_security(inode); 4022 struct task_security_struct *tsec = selinux_cred(new); 4023 u32 sid = current_sid(); 4024 int ret; 4025 4026 ret = avc_has_perm(sid, isec->sid, 4027 SECCLASS_KERNEL_SERVICE, 4028 KERNEL_SERVICE__CREATE_FILES_AS, 4029 NULL); 4030 4031 if (ret == 0) 4032 tsec->create_sid = isec->sid; 4033 return ret; 4034 } 4035 4036 static int selinux_kernel_module_request(char *kmod_name) 4037 { 4038 struct common_audit_data ad; 4039 4040 ad.type = LSM_AUDIT_DATA_KMOD; 4041 ad.u.kmod_name = kmod_name; 4042 4043 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4044 SYSTEM__MODULE_REQUEST, &ad); 4045 } 4046 4047 static int selinux_kernel_module_from_file(struct file *file) 4048 { 4049 struct common_audit_data ad; 4050 struct inode_security_struct *isec; 4051 struct file_security_struct *fsec; 4052 u32 sid = current_sid(); 4053 int rc; 4054 4055 /* init_module */ 4056 if (file == NULL) 4057 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 4058 SYSTEM__MODULE_LOAD, NULL); 4059 4060 /* finit_module */ 4061 4062 ad.type = LSM_AUDIT_DATA_FILE; 4063 ad.u.file = file; 4064 4065 fsec = selinux_file(file); 4066 if (sid != fsec->sid) { 4067 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4068 if (rc) 4069 return rc; 4070 } 4071 4072 isec = inode_security(file_inode(file)); 4073 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 4074 SYSTEM__MODULE_LOAD, &ad); 4075 } 4076 4077 static int selinux_kernel_read_file(struct file *file, 4078 enum kernel_read_file_id id, 4079 bool contents) 4080 { 4081 int rc = 0; 4082 4083 switch (id) { 4084 case READING_MODULE: 4085 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4086 break; 4087 default: 4088 break; 4089 } 4090 4091 return rc; 4092 } 4093 4094 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4095 { 4096 int rc = 0; 4097 4098 switch (id) { 4099 case LOADING_MODULE: 4100 rc = selinux_kernel_module_from_file(NULL); 4101 break; 4102 default: 4103 break; 4104 } 4105 4106 return rc; 4107 } 4108 4109 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4110 { 4111 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4112 PROCESS__SETPGID, NULL); 4113 } 4114 4115 static int selinux_task_getpgid(struct task_struct *p) 4116 { 4117 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4118 PROCESS__GETPGID, NULL); 4119 } 4120 4121 static int selinux_task_getsid(struct task_struct *p) 4122 { 4123 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4124 PROCESS__GETSESSION, NULL); 4125 } 4126 4127 static void selinux_current_getsecid_subj(u32 *secid) 4128 { 4129 *secid = current_sid(); 4130 } 4131 4132 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) 4133 { 4134 *secid = task_sid_obj(p); 4135 } 4136 4137 static int selinux_task_setnice(struct task_struct *p, int nice) 4138 { 4139 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4140 PROCESS__SETSCHED, NULL); 4141 } 4142 4143 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4144 { 4145 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4146 PROCESS__SETSCHED, NULL); 4147 } 4148 4149 static int selinux_task_getioprio(struct task_struct *p) 4150 { 4151 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4152 PROCESS__GETSCHED, NULL); 4153 } 4154 4155 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4156 unsigned int flags) 4157 { 4158 u32 av = 0; 4159 4160 if (!flags) 4161 return 0; 4162 if (flags & LSM_PRLIMIT_WRITE) 4163 av |= PROCESS__SETRLIMIT; 4164 if (flags & LSM_PRLIMIT_READ) 4165 av |= PROCESS__GETRLIMIT; 4166 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4167 SECCLASS_PROCESS, av, NULL); 4168 } 4169 4170 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4171 struct rlimit *new_rlim) 4172 { 4173 struct rlimit *old_rlim = p->signal->rlim + resource; 4174 4175 /* Control the ability to change the hard limit (whether 4176 lowering or raising it), so that the hard limit can 4177 later be used as a safe reset point for the soft limit 4178 upon context transitions. See selinux_bprm_committing_creds. */ 4179 if (old_rlim->rlim_max != new_rlim->rlim_max) 4180 return avc_has_perm(current_sid(), task_sid_obj(p), 4181 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4182 4183 return 0; 4184 } 4185 4186 static int selinux_task_setscheduler(struct task_struct *p) 4187 { 4188 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4189 PROCESS__SETSCHED, NULL); 4190 } 4191 4192 static int selinux_task_getscheduler(struct task_struct *p) 4193 { 4194 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4195 PROCESS__GETSCHED, NULL); 4196 } 4197 4198 static int selinux_task_movememory(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_kill(struct task_struct *p, struct kernel_siginfo *info, 4205 int sig, const struct cred *cred) 4206 { 4207 u32 secid; 4208 u32 perm; 4209 4210 if (!sig) 4211 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4212 else 4213 perm = signal_to_av(sig); 4214 if (!cred) 4215 secid = current_sid(); 4216 else 4217 secid = cred_sid(cred); 4218 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4219 } 4220 4221 static void selinux_task_to_inode(struct task_struct *p, 4222 struct inode *inode) 4223 { 4224 struct inode_security_struct *isec = selinux_inode(inode); 4225 u32 sid = task_sid_obj(p); 4226 4227 spin_lock(&isec->lock); 4228 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4229 isec->sid = sid; 4230 isec->initialized = LABEL_INITIALIZED; 4231 spin_unlock(&isec->lock); 4232 } 4233 4234 static int selinux_userns_create(const struct cred *cred) 4235 { 4236 u32 sid = current_sid(); 4237 4238 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4239 USER_NAMESPACE__CREATE, NULL); 4240 } 4241 4242 /* Returns error only if unable to parse addresses */ 4243 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4244 struct common_audit_data *ad, u8 *proto) 4245 { 4246 int offset, ihlen, ret = -EINVAL; 4247 struct iphdr _iph, *ih; 4248 4249 offset = skb_network_offset(skb); 4250 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4251 if (ih == NULL) 4252 goto out; 4253 4254 ihlen = ih->ihl * 4; 4255 if (ihlen < sizeof(_iph)) 4256 goto out; 4257 4258 ad->u.net->v4info.saddr = ih->saddr; 4259 ad->u.net->v4info.daddr = ih->daddr; 4260 ret = 0; 4261 4262 if (proto) 4263 *proto = ih->protocol; 4264 4265 switch (ih->protocol) { 4266 case IPPROTO_TCP: { 4267 struct tcphdr _tcph, *th; 4268 4269 if (ntohs(ih->frag_off) & IP_OFFSET) 4270 break; 4271 4272 offset += ihlen; 4273 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4274 if (th == NULL) 4275 break; 4276 4277 ad->u.net->sport = th->source; 4278 ad->u.net->dport = th->dest; 4279 break; 4280 } 4281 4282 case IPPROTO_UDP: { 4283 struct udphdr _udph, *uh; 4284 4285 if (ntohs(ih->frag_off) & IP_OFFSET) 4286 break; 4287 4288 offset += ihlen; 4289 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4290 if (uh == NULL) 4291 break; 4292 4293 ad->u.net->sport = uh->source; 4294 ad->u.net->dport = uh->dest; 4295 break; 4296 } 4297 4298 case IPPROTO_DCCP: { 4299 struct dccp_hdr _dccph, *dh; 4300 4301 if (ntohs(ih->frag_off) & IP_OFFSET) 4302 break; 4303 4304 offset += ihlen; 4305 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4306 if (dh == NULL) 4307 break; 4308 4309 ad->u.net->sport = dh->dccph_sport; 4310 ad->u.net->dport = dh->dccph_dport; 4311 break; 4312 } 4313 4314 #if IS_ENABLED(CONFIG_IP_SCTP) 4315 case IPPROTO_SCTP: { 4316 struct sctphdr _sctph, *sh; 4317 4318 if (ntohs(ih->frag_off) & IP_OFFSET) 4319 break; 4320 4321 offset += ihlen; 4322 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4323 if (sh == NULL) 4324 break; 4325 4326 ad->u.net->sport = sh->source; 4327 ad->u.net->dport = sh->dest; 4328 break; 4329 } 4330 #endif 4331 default: 4332 break; 4333 } 4334 out: 4335 return ret; 4336 } 4337 4338 #if IS_ENABLED(CONFIG_IPV6) 4339 4340 /* Returns error only if unable to parse addresses */ 4341 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4342 struct common_audit_data *ad, u8 *proto) 4343 { 4344 u8 nexthdr; 4345 int ret = -EINVAL, offset; 4346 struct ipv6hdr _ipv6h, *ip6; 4347 __be16 frag_off; 4348 4349 offset = skb_network_offset(skb); 4350 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4351 if (ip6 == NULL) 4352 goto out; 4353 4354 ad->u.net->v6info.saddr = ip6->saddr; 4355 ad->u.net->v6info.daddr = ip6->daddr; 4356 ret = 0; 4357 4358 nexthdr = ip6->nexthdr; 4359 offset += sizeof(_ipv6h); 4360 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4361 if (offset < 0) 4362 goto out; 4363 4364 if (proto) 4365 *proto = nexthdr; 4366 4367 switch (nexthdr) { 4368 case IPPROTO_TCP: { 4369 struct tcphdr _tcph, *th; 4370 4371 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4372 if (th == NULL) 4373 break; 4374 4375 ad->u.net->sport = th->source; 4376 ad->u.net->dport = th->dest; 4377 break; 4378 } 4379 4380 case IPPROTO_UDP: { 4381 struct udphdr _udph, *uh; 4382 4383 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4384 if (uh == NULL) 4385 break; 4386 4387 ad->u.net->sport = uh->source; 4388 ad->u.net->dport = uh->dest; 4389 break; 4390 } 4391 4392 case IPPROTO_DCCP: { 4393 struct dccp_hdr _dccph, *dh; 4394 4395 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4396 if (dh == NULL) 4397 break; 4398 4399 ad->u.net->sport = dh->dccph_sport; 4400 ad->u.net->dport = dh->dccph_dport; 4401 break; 4402 } 4403 4404 #if IS_ENABLED(CONFIG_IP_SCTP) 4405 case IPPROTO_SCTP: { 4406 struct sctphdr _sctph, *sh; 4407 4408 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4409 if (sh == NULL) 4410 break; 4411 4412 ad->u.net->sport = sh->source; 4413 ad->u.net->dport = sh->dest; 4414 break; 4415 } 4416 #endif 4417 /* includes fragments */ 4418 default: 4419 break; 4420 } 4421 out: 4422 return ret; 4423 } 4424 4425 #endif /* IPV6 */ 4426 4427 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4428 char **_addrp, int src, u8 *proto) 4429 { 4430 char *addrp; 4431 int ret; 4432 4433 switch (ad->u.net->family) { 4434 case PF_INET: 4435 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4436 if (ret) 4437 goto parse_error; 4438 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4439 &ad->u.net->v4info.daddr); 4440 goto okay; 4441 4442 #if IS_ENABLED(CONFIG_IPV6) 4443 case PF_INET6: 4444 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4445 if (ret) 4446 goto parse_error; 4447 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4448 &ad->u.net->v6info.daddr); 4449 goto okay; 4450 #endif /* IPV6 */ 4451 default: 4452 addrp = NULL; 4453 goto okay; 4454 } 4455 4456 parse_error: 4457 pr_warn( 4458 "SELinux: failure in selinux_parse_skb()," 4459 " unable to parse packet\n"); 4460 return ret; 4461 4462 okay: 4463 if (_addrp) 4464 *_addrp = addrp; 4465 return 0; 4466 } 4467 4468 /** 4469 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4470 * @skb: the packet 4471 * @family: protocol family 4472 * @sid: the packet's peer label SID 4473 * 4474 * Description: 4475 * Check the various different forms of network peer labeling and determine 4476 * the peer label/SID for the packet; most of the magic actually occurs in 4477 * the security server function security_net_peersid_cmp(). The function 4478 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4479 * or -EACCES if @sid is invalid due to inconsistencies with the different 4480 * peer labels. 4481 * 4482 */ 4483 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4484 { 4485 int err; 4486 u32 xfrm_sid; 4487 u32 nlbl_sid; 4488 u32 nlbl_type; 4489 4490 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4491 if (unlikely(err)) 4492 return -EACCES; 4493 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4494 if (unlikely(err)) 4495 return -EACCES; 4496 4497 err = security_net_peersid_resolve(nlbl_sid, 4498 nlbl_type, xfrm_sid, sid); 4499 if (unlikely(err)) { 4500 pr_warn( 4501 "SELinux: failure in selinux_skb_peerlbl_sid()," 4502 " unable to determine packet's peer label\n"); 4503 return -EACCES; 4504 } 4505 4506 return 0; 4507 } 4508 4509 /** 4510 * selinux_conn_sid - Determine the child socket label for a connection 4511 * @sk_sid: the parent socket's SID 4512 * @skb_sid: the packet's SID 4513 * @conn_sid: the resulting connection SID 4514 * 4515 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4516 * combined with the MLS information from @skb_sid in order to create 4517 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4518 * of @sk_sid. Returns zero on success, negative values on failure. 4519 * 4520 */ 4521 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4522 { 4523 int err = 0; 4524 4525 if (skb_sid != SECSID_NULL) 4526 err = security_sid_mls_copy(sk_sid, skb_sid, 4527 conn_sid); 4528 else 4529 *conn_sid = sk_sid; 4530 4531 return err; 4532 } 4533 4534 /* socket security operations */ 4535 4536 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4537 u16 secclass, u32 *socksid) 4538 { 4539 if (tsec->sockcreate_sid > SECSID_NULL) { 4540 *socksid = tsec->sockcreate_sid; 4541 return 0; 4542 } 4543 4544 return security_transition_sid(tsec->sid, tsec->sid, 4545 secclass, NULL, socksid); 4546 } 4547 4548 static int sock_has_perm(struct sock *sk, u32 perms) 4549 { 4550 struct sk_security_struct *sksec = sk->sk_security; 4551 struct common_audit_data ad; 4552 struct lsm_network_audit net; 4553 4554 if (sksec->sid == SECINITSID_KERNEL) 4555 return 0; 4556 4557 ad_net_init_from_sk(&ad, &net, sk); 4558 4559 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4560 &ad); 4561 } 4562 4563 static int selinux_socket_create(int family, int type, 4564 int protocol, int kern) 4565 { 4566 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4567 u32 newsid; 4568 u16 secclass; 4569 int rc; 4570 4571 if (kern) 4572 return 0; 4573 4574 secclass = socket_type_to_security_class(family, type, protocol); 4575 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4576 if (rc) 4577 return rc; 4578 4579 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4580 } 4581 4582 static int selinux_socket_post_create(struct socket *sock, int family, 4583 int type, int protocol, int kern) 4584 { 4585 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4586 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4587 struct sk_security_struct *sksec; 4588 u16 sclass = socket_type_to_security_class(family, type, protocol); 4589 u32 sid = SECINITSID_KERNEL; 4590 int err = 0; 4591 4592 if (!kern) { 4593 err = socket_sockcreate_sid(tsec, sclass, &sid); 4594 if (err) 4595 return err; 4596 } 4597 4598 isec->sclass = sclass; 4599 isec->sid = sid; 4600 isec->initialized = LABEL_INITIALIZED; 4601 4602 if (sock->sk) { 4603 sksec = sock->sk->sk_security; 4604 sksec->sclass = sclass; 4605 sksec->sid = sid; 4606 /* Allows detection of the first association on this socket */ 4607 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4608 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4609 4610 err = selinux_netlbl_socket_post_create(sock->sk, family); 4611 } 4612 4613 return err; 4614 } 4615 4616 static int selinux_socket_socketpair(struct socket *socka, 4617 struct socket *sockb) 4618 { 4619 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4620 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4621 4622 sksec_a->peer_sid = sksec_b->sid; 4623 sksec_b->peer_sid = sksec_a->sid; 4624 4625 return 0; 4626 } 4627 4628 /* Range of port numbers used to automatically bind. 4629 Need to determine whether we should perform a name_bind 4630 permission check between the socket and the port number. */ 4631 4632 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4633 { 4634 struct sock *sk = sock->sk; 4635 struct sk_security_struct *sksec = sk->sk_security; 4636 u16 family; 4637 int err; 4638 4639 err = sock_has_perm(sk, SOCKET__BIND); 4640 if (err) 4641 goto out; 4642 4643 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4644 family = sk->sk_family; 4645 if (family == PF_INET || family == PF_INET6) { 4646 char *addrp; 4647 struct common_audit_data ad; 4648 struct lsm_network_audit net = {0,}; 4649 struct sockaddr_in *addr4 = NULL; 4650 struct sockaddr_in6 *addr6 = NULL; 4651 u16 family_sa; 4652 unsigned short snum; 4653 u32 sid, node_perm; 4654 4655 /* 4656 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4657 * that validates multiple binding addresses. Because of this 4658 * need to check address->sa_family as it is possible to have 4659 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4660 */ 4661 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4662 return -EINVAL; 4663 family_sa = address->sa_family; 4664 switch (family_sa) { 4665 case AF_UNSPEC: 4666 case AF_INET: 4667 if (addrlen < sizeof(struct sockaddr_in)) 4668 return -EINVAL; 4669 addr4 = (struct sockaddr_in *)address; 4670 if (family_sa == AF_UNSPEC) { 4671 /* see __inet_bind(), we only want to allow 4672 * AF_UNSPEC if the address is INADDR_ANY 4673 */ 4674 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4675 goto err_af; 4676 family_sa = AF_INET; 4677 } 4678 snum = ntohs(addr4->sin_port); 4679 addrp = (char *)&addr4->sin_addr.s_addr; 4680 break; 4681 case AF_INET6: 4682 if (addrlen < SIN6_LEN_RFC2133) 4683 return -EINVAL; 4684 addr6 = (struct sockaddr_in6 *)address; 4685 snum = ntohs(addr6->sin6_port); 4686 addrp = (char *)&addr6->sin6_addr.s6_addr; 4687 break; 4688 default: 4689 goto err_af; 4690 } 4691 4692 ad.type = LSM_AUDIT_DATA_NET; 4693 ad.u.net = &net; 4694 ad.u.net->sport = htons(snum); 4695 ad.u.net->family = family_sa; 4696 4697 if (snum) { 4698 int low, high; 4699 4700 inet_get_local_port_range(sock_net(sk), &low, &high); 4701 4702 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4703 snum < low || snum > high) { 4704 err = sel_netport_sid(sk->sk_protocol, 4705 snum, &sid); 4706 if (err) 4707 goto out; 4708 err = avc_has_perm(sksec->sid, sid, 4709 sksec->sclass, 4710 SOCKET__NAME_BIND, &ad); 4711 if (err) 4712 goto out; 4713 } 4714 } 4715 4716 switch (sksec->sclass) { 4717 case SECCLASS_TCP_SOCKET: 4718 node_perm = TCP_SOCKET__NODE_BIND; 4719 break; 4720 4721 case SECCLASS_UDP_SOCKET: 4722 node_perm = UDP_SOCKET__NODE_BIND; 4723 break; 4724 4725 case SECCLASS_DCCP_SOCKET: 4726 node_perm = DCCP_SOCKET__NODE_BIND; 4727 break; 4728 4729 case SECCLASS_SCTP_SOCKET: 4730 node_perm = SCTP_SOCKET__NODE_BIND; 4731 break; 4732 4733 default: 4734 node_perm = RAWIP_SOCKET__NODE_BIND; 4735 break; 4736 } 4737 4738 err = sel_netnode_sid(addrp, family_sa, &sid); 4739 if (err) 4740 goto out; 4741 4742 if (family_sa == AF_INET) 4743 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4744 else 4745 ad.u.net->v6info.saddr = addr6->sin6_addr; 4746 4747 err = avc_has_perm(sksec->sid, sid, 4748 sksec->sclass, node_perm, &ad); 4749 if (err) 4750 goto out; 4751 } 4752 out: 4753 return err; 4754 err_af: 4755 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4756 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4757 return -EINVAL; 4758 return -EAFNOSUPPORT; 4759 } 4760 4761 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4762 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4763 */ 4764 static int selinux_socket_connect_helper(struct socket *sock, 4765 struct sockaddr *address, int addrlen) 4766 { 4767 struct sock *sk = sock->sk; 4768 struct sk_security_struct *sksec = sk->sk_security; 4769 int err; 4770 4771 err = sock_has_perm(sk, SOCKET__CONNECT); 4772 if (err) 4773 return err; 4774 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4775 return -EINVAL; 4776 4777 /* connect(AF_UNSPEC) has special handling, as it is a documented 4778 * way to disconnect the socket 4779 */ 4780 if (address->sa_family == AF_UNSPEC) 4781 return 0; 4782 4783 /* 4784 * If a TCP, DCCP or SCTP socket, check name_connect permission 4785 * for the port. 4786 */ 4787 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4788 sksec->sclass == SECCLASS_DCCP_SOCKET || 4789 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4790 struct common_audit_data ad; 4791 struct lsm_network_audit net = {0,}; 4792 struct sockaddr_in *addr4 = NULL; 4793 struct sockaddr_in6 *addr6 = NULL; 4794 unsigned short snum; 4795 u32 sid, perm; 4796 4797 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4798 * that validates multiple connect addresses. Because of this 4799 * need to check address->sa_family as it is possible to have 4800 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4801 */ 4802 switch (address->sa_family) { 4803 case AF_INET: 4804 addr4 = (struct sockaddr_in *)address; 4805 if (addrlen < sizeof(struct sockaddr_in)) 4806 return -EINVAL; 4807 snum = ntohs(addr4->sin_port); 4808 break; 4809 case AF_INET6: 4810 addr6 = (struct sockaddr_in6 *)address; 4811 if (addrlen < SIN6_LEN_RFC2133) 4812 return -EINVAL; 4813 snum = ntohs(addr6->sin6_port); 4814 break; 4815 default: 4816 /* Note that SCTP services expect -EINVAL, whereas 4817 * others expect -EAFNOSUPPORT. 4818 */ 4819 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4820 return -EINVAL; 4821 else 4822 return -EAFNOSUPPORT; 4823 } 4824 4825 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4826 if (err) 4827 return err; 4828 4829 switch (sksec->sclass) { 4830 case SECCLASS_TCP_SOCKET: 4831 perm = TCP_SOCKET__NAME_CONNECT; 4832 break; 4833 case SECCLASS_DCCP_SOCKET: 4834 perm = DCCP_SOCKET__NAME_CONNECT; 4835 break; 4836 case SECCLASS_SCTP_SOCKET: 4837 perm = SCTP_SOCKET__NAME_CONNECT; 4838 break; 4839 } 4840 4841 ad.type = LSM_AUDIT_DATA_NET; 4842 ad.u.net = &net; 4843 ad.u.net->dport = htons(snum); 4844 ad.u.net->family = address->sa_family; 4845 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4846 if (err) 4847 return err; 4848 } 4849 4850 return 0; 4851 } 4852 4853 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4854 static int selinux_socket_connect(struct socket *sock, 4855 struct sockaddr *address, int addrlen) 4856 { 4857 int err; 4858 struct sock *sk = sock->sk; 4859 4860 err = selinux_socket_connect_helper(sock, address, addrlen); 4861 if (err) 4862 return err; 4863 4864 return selinux_netlbl_socket_connect(sk, address); 4865 } 4866 4867 static int selinux_socket_listen(struct socket *sock, int backlog) 4868 { 4869 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4870 } 4871 4872 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4873 { 4874 int err; 4875 struct inode_security_struct *isec; 4876 struct inode_security_struct *newisec; 4877 u16 sclass; 4878 u32 sid; 4879 4880 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4881 if (err) 4882 return err; 4883 4884 isec = inode_security_novalidate(SOCK_INODE(sock)); 4885 spin_lock(&isec->lock); 4886 sclass = isec->sclass; 4887 sid = isec->sid; 4888 spin_unlock(&isec->lock); 4889 4890 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4891 newisec->sclass = sclass; 4892 newisec->sid = sid; 4893 newisec->initialized = LABEL_INITIALIZED; 4894 4895 return 0; 4896 } 4897 4898 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4899 int size) 4900 { 4901 return sock_has_perm(sock->sk, SOCKET__WRITE); 4902 } 4903 4904 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4905 int size, int flags) 4906 { 4907 return sock_has_perm(sock->sk, SOCKET__READ); 4908 } 4909 4910 static int selinux_socket_getsockname(struct socket *sock) 4911 { 4912 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4913 } 4914 4915 static int selinux_socket_getpeername(struct socket *sock) 4916 { 4917 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4918 } 4919 4920 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4921 { 4922 int err; 4923 4924 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4925 if (err) 4926 return err; 4927 4928 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4929 } 4930 4931 static int selinux_socket_getsockopt(struct socket *sock, int level, 4932 int optname) 4933 { 4934 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4935 } 4936 4937 static int selinux_socket_shutdown(struct socket *sock, int how) 4938 { 4939 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4940 } 4941 4942 static int selinux_socket_unix_stream_connect(struct sock *sock, 4943 struct sock *other, 4944 struct sock *newsk) 4945 { 4946 struct sk_security_struct *sksec_sock = sock->sk_security; 4947 struct sk_security_struct *sksec_other = other->sk_security; 4948 struct sk_security_struct *sksec_new = newsk->sk_security; 4949 struct common_audit_data ad; 4950 struct lsm_network_audit net; 4951 int err; 4952 4953 ad_net_init_from_sk(&ad, &net, other); 4954 4955 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4956 sksec_other->sclass, 4957 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4958 if (err) 4959 return err; 4960 4961 /* server child socket */ 4962 sksec_new->peer_sid = sksec_sock->sid; 4963 err = security_sid_mls_copy(sksec_other->sid, 4964 sksec_sock->sid, &sksec_new->sid); 4965 if (err) 4966 return err; 4967 4968 /* connecting socket */ 4969 sksec_sock->peer_sid = sksec_new->sid; 4970 4971 return 0; 4972 } 4973 4974 static int selinux_socket_unix_may_send(struct socket *sock, 4975 struct socket *other) 4976 { 4977 struct sk_security_struct *ssec = sock->sk->sk_security; 4978 struct sk_security_struct *osec = other->sk->sk_security; 4979 struct common_audit_data ad; 4980 struct lsm_network_audit net; 4981 4982 ad_net_init_from_sk(&ad, &net, other->sk); 4983 4984 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4985 &ad); 4986 } 4987 4988 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4989 char *addrp, u16 family, u32 peer_sid, 4990 struct common_audit_data *ad) 4991 { 4992 int err; 4993 u32 if_sid; 4994 u32 node_sid; 4995 4996 err = sel_netif_sid(ns, ifindex, &if_sid); 4997 if (err) 4998 return err; 4999 err = avc_has_perm(peer_sid, if_sid, 5000 SECCLASS_NETIF, NETIF__INGRESS, ad); 5001 if (err) 5002 return err; 5003 5004 err = sel_netnode_sid(addrp, family, &node_sid); 5005 if (err) 5006 return err; 5007 return avc_has_perm(peer_sid, node_sid, 5008 SECCLASS_NODE, NODE__RECVFROM, ad); 5009 } 5010 5011 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5012 u16 family) 5013 { 5014 int err = 0; 5015 struct sk_security_struct *sksec = sk->sk_security; 5016 u32 sk_sid = sksec->sid; 5017 struct common_audit_data ad; 5018 struct lsm_network_audit net; 5019 char *addrp; 5020 5021 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5022 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5023 if (err) 5024 return err; 5025 5026 if (selinux_secmark_enabled()) { 5027 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5028 PACKET__RECV, &ad); 5029 if (err) 5030 return err; 5031 } 5032 5033 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5034 if (err) 5035 return err; 5036 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5037 5038 return err; 5039 } 5040 5041 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5042 { 5043 int err, peerlbl_active, secmark_active; 5044 struct sk_security_struct *sksec = sk->sk_security; 5045 u16 family = sk->sk_family; 5046 u32 sk_sid = sksec->sid; 5047 struct common_audit_data ad; 5048 struct lsm_network_audit net; 5049 char *addrp; 5050 5051 if (family != PF_INET && family != PF_INET6) 5052 return 0; 5053 5054 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5055 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5056 family = PF_INET; 5057 5058 /* If any sort of compatibility mode is enabled then handoff processing 5059 * to the selinux_sock_rcv_skb_compat() function to deal with the 5060 * special handling. We do this in an attempt to keep this function 5061 * as fast and as clean as possible. */ 5062 if (!selinux_policycap_netpeer()) 5063 return selinux_sock_rcv_skb_compat(sk, skb, family); 5064 5065 secmark_active = selinux_secmark_enabled(); 5066 peerlbl_active = selinux_peerlbl_enabled(); 5067 if (!secmark_active && !peerlbl_active) 5068 return 0; 5069 5070 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5071 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5072 if (err) 5073 return err; 5074 5075 if (peerlbl_active) { 5076 u32 peer_sid; 5077 5078 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5079 if (err) 5080 return err; 5081 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5082 addrp, family, peer_sid, &ad); 5083 if (err) { 5084 selinux_netlbl_err(skb, family, err, 0); 5085 return err; 5086 } 5087 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5088 PEER__RECV, &ad); 5089 if (err) { 5090 selinux_netlbl_err(skb, family, err, 0); 5091 return err; 5092 } 5093 } 5094 5095 if (secmark_active) { 5096 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5097 PACKET__RECV, &ad); 5098 if (err) 5099 return err; 5100 } 5101 5102 return err; 5103 } 5104 5105 static int selinux_socket_getpeersec_stream(struct socket *sock, 5106 sockptr_t optval, sockptr_t optlen, 5107 unsigned int len) 5108 { 5109 int err = 0; 5110 char *scontext = NULL; 5111 u32 scontext_len; 5112 struct sk_security_struct *sksec = sock->sk->sk_security; 5113 u32 peer_sid = SECSID_NULL; 5114 5115 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5116 sksec->sclass == SECCLASS_TCP_SOCKET || 5117 sksec->sclass == SECCLASS_SCTP_SOCKET) 5118 peer_sid = sksec->peer_sid; 5119 if (peer_sid == SECSID_NULL) 5120 return -ENOPROTOOPT; 5121 5122 err = security_sid_to_context(peer_sid, &scontext, 5123 &scontext_len); 5124 if (err) 5125 return err; 5126 if (scontext_len > len) { 5127 err = -ERANGE; 5128 goto out_len; 5129 } 5130 5131 if (copy_to_sockptr(optval, scontext, scontext_len)) 5132 err = -EFAULT; 5133 out_len: 5134 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5135 err = -EFAULT; 5136 kfree(scontext); 5137 return err; 5138 } 5139 5140 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5141 { 5142 u32 peer_secid = SECSID_NULL; 5143 u16 family; 5144 struct inode_security_struct *isec; 5145 5146 if (skb && skb->protocol == htons(ETH_P_IP)) 5147 family = PF_INET; 5148 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5149 family = PF_INET6; 5150 else if (sock) 5151 family = sock->sk->sk_family; 5152 else 5153 goto out; 5154 5155 if (sock && family == PF_UNIX) { 5156 isec = inode_security_novalidate(SOCK_INODE(sock)); 5157 peer_secid = isec->sid; 5158 } else if (skb) 5159 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5160 5161 out: 5162 *secid = peer_secid; 5163 if (peer_secid == SECSID_NULL) 5164 return -EINVAL; 5165 return 0; 5166 } 5167 5168 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5169 { 5170 struct sk_security_struct *sksec; 5171 5172 sksec = kzalloc(sizeof(*sksec), priority); 5173 if (!sksec) 5174 return -ENOMEM; 5175 5176 sksec->peer_sid = SECINITSID_UNLABELED; 5177 sksec->sid = SECINITSID_UNLABELED; 5178 sksec->sclass = SECCLASS_SOCKET; 5179 selinux_netlbl_sk_security_reset(sksec); 5180 sk->sk_security = sksec; 5181 5182 return 0; 5183 } 5184 5185 static void selinux_sk_free_security(struct sock *sk) 5186 { 5187 struct sk_security_struct *sksec = sk->sk_security; 5188 5189 sk->sk_security = NULL; 5190 selinux_netlbl_sk_security_free(sksec); 5191 kfree(sksec); 5192 } 5193 5194 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5195 { 5196 struct sk_security_struct *sksec = sk->sk_security; 5197 struct sk_security_struct *newsksec = newsk->sk_security; 5198 5199 newsksec->sid = sksec->sid; 5200 newsksec->peer_sid = sksec->peer_sid; 5201 newsksec->sclass = sksec->sclass; 5202 5203 selinux_netlbl_sk_security_reset(newsksec); 5204 } 5205 5206 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5207 { 5208 if (!sk) 5209 *secid = SECINITSID_ANY_SOCKET; 5210 else { 5211 const struct sk_security_struct *sksec = sk->sk_security; 5212 5213 *secid = sksec->sid; 5214 } 5215 } 5216 5217 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5218 { 5219 struct inode_security_struct *isec = 5220 inode_security_novalidate(SOCK_INODE(parent)); 5221 struct sk_security_struct *sksec = sk->sk_security; 5222 5223 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5224 sk->sk_family == PF_UNIX) 5225 isec->sid = sksec->sid; 5226 sksec->sclass = isec->sclass; 5227 } 5228 5229 /* 5230 * Determines peer_secid for the asoc and updates socket's peer label 5231 * if it's the first association on the socket. 5232 */ 5233 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5234 struct sk_buff *skb) 5235 { 5236 struct sock *sk = asoc->base.sk; 5237 u16 family = sk->sk_family; 5238 struct sk_security_struct *sksec = sk->sk_security; 5239 struct common_audit_data ad; 5240 struct lsm_network_audit net; 5241 int err; 5242 5243 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5244 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5245 family = PF_INET; 5246 5247 if (selinux_peerlbl_enabled()) { 5248 asoc->peer_secid = SECSID_NULL; 5249 5250 /* This will return peer_sid = SECSID_NULL if there are 5251 * no peer labels, see security_net_peersid_resolve(). 5252 */ 5253 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5254 if (err) 5255 return err; 5256 5257 if (asoc->peer_secid == SECSID_NULL) 5258 asoc->peer_secid = SECINITSID_UNLABELED; 5259 } else { 5260 asoc->peer_secid = SECINITSID_UNLABELED; 5261 } 5262 5263 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5264 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5265 5266 /* Here as first association on socket. As the peer SID 5267 * was allowed by peer recv (and the netif/node checks), 5268 * then it is approved by policy and used as the primary 5269 * peer SID for getpeercon(3). 5270 */ 5271 sksec->peer_sid = asoc->peer_secid; 5272 } else if (sksec->peer_sid != asoc->peer_secid) { 5273 /* Other association peer SIDs are checked to enforce 5274 * consistency among the peer SIDs. 5275 */ 5276 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5277 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5278 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5279 &ad); 5280 if (err) 5281 return err; 5282 } 5283 return 0; 5284 } 5285 5286 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5287 * happens on an incoming connect(2), sctp_connectx(3) or 5288 * sctp_sendmsg(3) (with no association already present). 5289 */ 5290 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5291 struct sk_buff *skb) 5292 { 5293 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5294 u32 conn_sid; 5295 int err; 5296 5297 if (!selinux_policycap_extsockclass()) 5298 return 0; 5299 5300 err = selinux_sctp_process_new_assoc(asoc, skb); 5301 if (err) 5302 return err; 5303 5304 /* Compute the MLS component for the connection and store 5305 * the information in asoc. This will be used by SCTP TCP type 5306 * sockets and peeled off connections as they cause a new 5307 * socket to be generated. selinux_sctp_sk_clone() will then 5308 * plug this into the new socket. 5309 */ 5310 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5311 if (err) 5312 return err; 5313 5314 asoc->secid = conn_sid; 5315 5316 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5317 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5318 } 5319 5320 /* Called when SCTP receives a COOKIE ACK chunk as the final 5321 * response to an association request (initited by us). 5322 */ 5323 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5324 struct sk_buff *skb) 5325 { 5326 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5327 5328 if (!selinux_policycap_extsockclass()) 5329 return 0; 5330 5331 /* Inherit secid from the parent socket - this will be picked up 5332 * by selinux_sctp_sk_clone() if the association gets peeled off 5333 * into a new socket. 5334 */ 5335 asoc->secid = sksec->sid; 5336 5337 return selinux_sctp_process_new_assoc(asoc, skb); 5338 } 5339 5340 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5341 * based on their @optname. 5342 */ 5343 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5344 struct sockaddr *address, 5345 int addrlen) 5346 { 5347 int len, err = 0, walk_size = 0; 5348 void *addr_buf; 5349 struct sockaddr *addr; 5350 struct socket *sock; 5351 5352 if (!selinux_policycap_extsockclass()) 5353 return 0; 5354 5355 /* Process one or more addresses that may be IPv4 or IPv6 */ 5356 sock = sk->sk_socket; 5357 addr_buf = address; 5358 5359 while (walk_size < addrlen) { 5360 if (walk_size + sizeof(sa_family_t) > addrlen) 5361 return -EINVAL; 5362 5363 addr = addr_buf; 5364 switch (addr->sa_family) { 5365 case AF_UNSPEC: 5366 case AF_INET: 5367 len = sizeof(struct sockaddr_in); 5368 break; 5369 case AF_INET6: 5370 len = sizeof(struct sockaddr_in6); 5371 break; 5372 default: 5373 return -EINVAL; 5374 } 5375 5376 if (walk_size + len > addrlen) 5377 return -EINVAL; 5378 5379 err = -EINVAL; 5380 switch (optname) { 5381 /* Bind checks */ 5382 case SCTP_PRIMARY_ADDR: 5383 case SCTP_SET_PEER_PRIMARY_ADDR: 5384 case SCTP_SOCKOPT_BINDX_ADD: 5385 err = selinux_socket_bind(sock, addr, len); 5386 break; 5387 /* Connect checks */ 5388 case SCTP_SOCKOPT_CONNECTX: 5389 case SCTP_PARAM_SET_PRIMARY: 5390 case SCTP_PARAM_ADD_IP: 5391 case SCTP_SENDMSG_CONNECT: 5392 err = selinux_socket_connect_helper(sock, addr, len); 5393 if (err) 5394 return err; 5395 5396 /* As selinux_sctp_bind_connect() is called by the 5397 * SCTP protocol layer, the socket is already locked, 5398 * therefore selinux_netlbl_socket_connect_locked() 5399 * is called here. The situations handled are: 5400 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5401 * whenever a new IP address is added or when a new 5402 * primary address is selected. 5403 * Note that an SCTP connect(2) call happens before 5404 * the SCTP protocol layer and is handled via 5405 * selinux_socket_connect(). 5406 */ 5407 err = selinux_netlbl_socket_connect_locked(sk, addr); 5408 break; 5409 } 5410 5411 if (err) 5412 return err; 5413 5414 addr_buf += len; 5415 walk_size += len; 5416 } 5417 5418 return 0; 5419 } 5420 5421 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5422 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5423 struct sock *newsk) 5424 { 5425 struct sk_security_struct *sksec = sk->sk_security; 5426 struct sk_security_struct *newsksec = newsk->sk_security; 5427 5428 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5429 * the non-sctp clone version. 5430 */ 5431 if (!selinux_policycap_extsockclass()) 5432 return selinux_sk_clone_security(sk, newsk); 5433 5434 newsksec->sid = asoc->secid; 5435 newsksec->peer_sid = asoc->peer_secid; 5436 newsksec->sclass = sksec->sclass; 5437 selinux_netlbl_sctp_sk_clone(sk, newsk); 5438 } 5439 5440 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5441 { 5442 struct sk_security_struct *ssksec = ssk->sk_security; 5443 struct sk_security_struct *sksec = sk->sk_security; 5444 5445 ssksec->sclass = sksec->sclass; 5446 ssksec->sid = sksec->sid; 5447 5448 /* replace the existing subflow label deleting the existing one 5449 * and re-recreating a new label using the updated context 5450 */ 5451 selinux_netlbl_sk_security_free(ssksec); 5452 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5453 } 5454 5455 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5456 struct request_sock *req) 5457 { 5458 struct sk_security_struct *sksec = sk->sk_security; 5459 int err; 5460 u16 family = req->rsk_ops->family; 5461 u32 connsid; 5462 u32 peersid; 5463 5464 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5465 if (err) 5466 return err; 5467 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5468 if (err) 5469 return err; 5470 req->secid = connsid; 5471 req->peer_secid = peersid; 5472 5473 return selinux_netlbl_inet_conn_request(req, family); 5474 } 5475 5476 static void selinux_inet_csk_clone(struct sock *newsk, 5477 const struct request_sock *req) 5478 { 5479 struct sk_security_struct *newsksec = newsk->sk_security; 5480 5481 newsksec->sid = req->secid; 5482 newsksec->peer_sid = req->peer_secid; 5483 /* NOTE: Ideally, we should also get the isec->sid for the 5484 new socket in sync, but we don't have the isec available yet. 5485 So we will wait until sock_graft to do it, by which 5486 time it will have been created and available. */ 5487 5488 /* We don't need to take any sort of lock here as we are the only 5489 * thread with access to newsksec */ 5490 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5491 } 5492 5493 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5494 { 5495 u16 family = sk->sk_family; 5496 struct sk_security_struct *sksec = sk->sk_security; 5497 5498 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5499 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5500 family = PF_INET; 5501 5502 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5503 } 5504 5505 static int selinux_secmark_relabel_packet(u32 sid) 5506 { 5507 const struct task_security_struct *tsec; 5508 u32 tsid; 5509 5510 tsec = selinux_cred(current_cred()); 5511 tsid = tsec->sid; 5512 5513 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5514 NULL); 5515 } 5516 5517 static void selinux_secmark_refcount_inc(void) 5518 { 5519 atomic_inc(&selinux_secmark_refcount); 5520 } 5521 5522 static void selinux_secmark_refcount_dec(void) 5523 { 5524 atomic_dec(&selinux_secmark_refcount); 5525 } 5526 5527 static void selinux_req_classify_flow(const struct request_sock *req, 5528 struct flowi_common *flic) 5529 { 5530 flic->flowic_secid = req->secid; 5531 } 5532 5533 static int selinux_tun_dev_alloc_security(void **security) 5534 { 5535 struct tun_security_struct *tunsec; 5536 5537 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5538 if (!tunsec) 5539 return -ENOMEM; 5540 tunsec->sid = current_sid(); 5541 5542 *security = tunsec; 5543 return 0; 5544 } 5545 5546 static void selinux_tun_dev_free_security(void *security) 5547 { 5548 kfree(security); 5549 } 5550 5551 static int selinux_tun_dev_create(void) 5552 { 5553 u32 sid = current_sid(); 5554 5555 /* we aren't taking into account the "sockcreate" SID since the socket 5556 * that is being created here is not a socket in the traditional sense, 5557 * instead it is a private sock, accessible only to the kernel, and 5558 * representing a wide range of network traffic spanning multiple 5559 * connections unlike traditional sockets - check the TUN driver to 5560 * get a better understanding of why this socket is special */ 5561 5562 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5563 NULL); 5564 } 5565 5566 static int selinux_tun_dev_attach_queue(void *security) 5567 { 5568 struct tun_security_struct *tunsec = security; 5569 5570 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5571 TUN_SOCKET__ATTACH_QUEUE, NULL); 5572 } 5573 5574 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5575 { 5576 struct tun_security_struct *tunsec = security; 5577 struct sk_security_struct *sksec = sk->sk_security; 5578 5579 /* we don't currently perform any NetLabel based labeling here and it 5580 * isn't clear that we would want to do so anyway; while we could apply 5581 * labeling without the support of the TUN user the resulting labeled 5582 * traffic from the other end of the connection would almost certainly 5583 * cause confusion to the TUN user that had no idea network labeling 5584 * protocols were being used */ 5585 5586 sksec->sid = tunsec->sid; 5587 sksec->sclass = SECCLASS_TUN_SOCKET; 5588 5589 return 0; 5590 } 5591 5592 static int selinux_tun_dev_open(void *security) 5593 { 5594 struct tun_security_struct *tunsec = security; 5595 u32 sid = current_sid(); 5596 int err; 5597 5598 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5599 TUN_SOCKET__RELABELFROM, NULL); 5600 if (err) 5601 return err; 5602 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5603 TUN_SOCKET__RELABELTO, NULL); 5604 if (err) 5605 return err; 5606 tunsec->sid = sid; 5607 5608 return 0; 5609 } 5610 5611 #ifdef CONFIG_NETFILTER 5612 5613 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5614 const struct nf_hook_state *state) 5615 { 5616 int ifindex; 5617 u16 family; 5618 char *addrp; 5619 u32 peer_sid; 5620 struct common_audit_data ad; 5621 struct lsm_network_audit net; 5622 int secmark_active, peerlbl_active; 5623 5624 if (!selinux_policycap_netpeer()) 5625 return NF_ACCEPT; 5626 5627 secmark_active = selinux_secmark_enabled(); 5628 peerlbl_active = selinux_peerlbl_enabled(); 5629 if (!secmark_active && !peerlbl_active) 5630 return NF_ACCEPT; 5631 5632 family = state->pf; 5633 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5634 return NF_DROP; 5635 5636 ifindex = state->in->ifindex; 5637 ad_net_init_from_iif(&ad, &net, ifindex, family); 5638 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5639 return NF_DROP; 5640 5641 if (peerlbl_active) { 5642 int err; 5643 5644 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5645 addrp, family, peer_sid, &ad); 5646 if (err) { 5647 selinux_netlbl_err(skb, family, err, 1); 5648 return NF_DROP; 5649 } 5650 } 5651 5652 if (secmark_active) 5653 if (avc_has_perm(peer_sid, skb->secmark, 5654 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5655 return NF_DROP; 5656 5657 if (netlbl_enabled()) 5658 /* we do this in the FORWARD path and not the POST_ROUTING 5659 * path because we want to make sure we apply the necessary 5660 * labeling before IPsec is applied so we can leverage AH 5661 * protection */ 5662 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5663 return NF_DROP; 5664 5665 return NF_ACCEPT; 5666 } 5667 5668 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5669 const struct nf_hook_state *state) 5670 { 5671 struct sock *sk; 5672 u32 sid; 5673 5674 if (!netlbl_enabled()) 5675 return NF_ACCEPT; 5676 5677 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5678 * because we want to make sure we apply the necessary labeling 5679 * before IPsec is applied so we can leverage AH protection */ 5680 sk = skb->sk; 5681 if (sk) { 5682 struct sk_security_struct *sksec; 5683 5684 if (sk_listener(sk)) 5685 /* if the socket is the listening state then this 5686 * packet is a SYN-ACK packet which means it needs to 5687 * be labeled based on the connection/request_sock and 5688 * not the parent socket. unfortunately, we can't 5689 * lookup the request_sock yet as it isn't queued on 5690 * the parent socket until after the SYN-ACK is sent. 5691 * the "solution" is to simply pass the packet as-is 5692 * as any IP option based labeling should be copied 5693 * from the initial connection request (in the IP 5694 * layer). it is far from ideal, but until we get a 5695 * security label in the packet itself this is the 5696 * best we can do. */ 5697 return NF_ACCEPT; 5698 5699 /* standard practice, label using the parent socket */ 5700 sksec = sk->sk_security; 5701 sid = sksec->sid; 5702 } else 5703 sid = SECINITSID_KERNEL; 5704 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5705 return NF_DROP; 5706 5707 return NF_ACCEPT; 5708 } 5709 5710 5711 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5712 const struct nf_hook_state *state) 5713 { 5714 struct sock *sk; 5715 struct sk_security_struct *sksec; 5716 struct common_audit_data ad; 5717 struct lsm_network_audit net; 5718 u8 proto = 0; 5719 5720 sk = skb_to_full_sk(skb); 5721 if (sk == NULL) 5722 return NF_ACCEPT; 5723 sksec = sk->sk_security; 5724 5725 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5726 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5727 return NF_DROP; 5728 5729 if (selinux_secmark_enabled()) 5730 if (avc_has_perm(sksec->sid, skb->secmark, 5731 SECCLASS_PACKET, PACKET__SEND, &ad)) 5732 return NF_DROP_ERR(-ECONNREFUSED); 5733 5734 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5735 return NF_DROP_ERR(-ECONNREFUSED); 5736 5737 return NF_ACCEPT; 5738 } 5739 5740 static unsigned int selinux_ip_postroute(void *priv, 5741 struct sk_buff *skb, 5742 const struct nf_hook_state *state) 5743 { 5744 u16 family; 5745 u32 secmark_perm; 5746 u32 peer_sid; 5747 int ifindex; 5748 struct sock *sk; 5749 struct common_audit_data ad; 5750 struct lsm_network_audit net; 5751 char *addrp; 5752 int secmark_active, peerlbl_active; 5753 5754 /* If any sort of compatibility mode is enabled then handoff processing 5755 * to the selinux_ip_postroute_compat() function to deal with the 5756 * special handling. We do this in an attempt to keep this function 5757 * as fast and as clean as possible. */ 5758 if (!selinux_policycap_netpeer()) 5759 return selinux_ip_postroute_compat(skb, state); 5760 5761 secmark_active = selinux_secmark_enabled(); 5762 peerlbl_active = selinux_peerlbl_enabled(); 5763 if (!secmark_active && !peerlbl_active) 5764 return NF_ACCEPT; 5765 5766 sk = skb_to_full_sk(skb); 5767 5768 #ifdef CONFIG_XFRM 5769 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5770 * packet transformation so allow the packet to pass without any checks 5771 * since we'll have another chance to perform access control checks 5772 * when the packet is on it's final way out. 5773 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5774 * is NULL, in this case go ahead and apply access control. 5775 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5776 * TCP listening state we cannot wait until the XFRM processing 5777 * is done as we will miss out on the SA label if we do; 5778 * unfortunately, this means more work, but it is only once per 5779 * connection. */ 5780 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5781 !(sk && sk_listener(sk))) 5782 return NF_ACCEPT; 5783 #endif 5784 5785 family = state->pf; 5786 if (sk == NULL) { 5787 /* Without an associated socket the packet is either coming 5788 * from the kernel or it is being forwarded; check the packet 5789 * to determine which and if the packet is being forwarded 5790 * query the packet directly to determine the security label. */ 5791 if (skb->skb_iif) { 5792 secmark_perm = PACKET__FORWARD_OUT; 5793 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5794 return NF_DROP; 5795 } else { 5796 secmark_perm = PACKET__SEND; 5797 peer_sid = SECINITSID_KERNEL; 5798 } 5799 } else if (sk_listener(sk)) { 5800 /* Locally generated packet but the associated socket is in the 5801 * listening state which means this is a SYN-ACK packet. In 5802 * this particular case the correct security label is assigned 5803 * to the connection/request_sock but unfortunately we can't 5804 * query the request_sock as it isn't queued on the parent 5805 * socket until after the SYN-ACK packet is sent; the only 5806 * viable choice is to regenerate the label like we do in 5807 * selinux_inet_conn_request(). See also selinux_ip_output() 5808 * for similar problems. */ 5809 u32 skb_sid; 5810 struct sk_security_struct *sksec; 5811 5812 sksec = sk->sk_security; 5813 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5814 return NF_DROP; 5815 /* At this point, if the returned skb peerlbl is SECSID_NULL 5816 * and the packet has been through at least one XFRM 5817 * transformation then we must be dealing with the "final" 5818 * form of labeled IPsec packet; since we've already applied 5819 * all of our access controls on this packet we can safely 5820 * pass the packet. */ 5821 if (skb_sid == SECSID_NULL) { 5822 switch (family) { 5823 case PF_INET: 5824 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5825 return NF_ACCEPT; 5826 break; 5827 case PF_INET6: 5828 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5829 return NF_ACCEPT; 5830 break; 5831 default: 5832 return NF_DROP_ERR(-ECONNREFUSED); 5833 } 5834 } 5835 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5836 return NF_DROP; 5837 secmark_perm = PACKET__SEND; 5838 } else { 5839 /* Locally generated packet, fetch the security label from the 5840 * associated socket. */ 5841 struct sk_security_struct *sksec = sk->sk_security; 5842 peer_sid = sksec->sid; 5843 secmark_perm = PACKET__SEND; 5844 } 5845 5846 ifindex = state->out->ifindex; 5847 ad_net_init_from_iif(&ad, &net, ifindex, family); 5848 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5849 return NF_DROP; 5850 5851 if (secmark_active) 5852 if (avc_has_perm(peer_sid, skb->secmark, 5853 SECCLASS_PACKET, secmark_perm, &ad)) 5854 return NF_DROP_ERR(-ECONNREFUSED); 5855 5856 if (peerlbl_active) { 5857 u32 if_sid; 5858 u32 node_sid; 5859 5860 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5861 return NF_DROP; 5862 if (avc_has_perm(peer_sid, if_sid, 5863 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5864 return NF_DROP_ERR(-ECONNREFUSED); 5865 5866 if (sel_netnode_sid(addrp, family, &node_sid)) 5867 return NF_DROP; 5868 if (avc_has_perm(peer_sid, node_sid, 5869 SECCLASS_NODE, NODE__SENDTO, &ad)) 5870 return NF_DROP_ERR(-ECONNREFUSED); 5871 } 5872 5873 return NF_ACCEPT; 5874 } 5875 #endif /* CONFIG_NETFILTER */ 5876 5877 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5878 { 5879 int rc = 0; 5880 unsigned int msg_len; 5881 unsigned int data_len = skb->len; 5882 unsigned char *data = skb->data; 5883 struct nlmsghdr *nlh; 5884 struct sk_security_struct *sksec = sk->sk_security; 5885 u16 sclass = sksec->sclass; 5886 u32 perm; 5887 5888 while (data_len >= nlmsg_total_size(0)) { 5889 nlh = (struct nlmsghdr *)data; 5890 5891 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5892 * users which means we can't reject skb's with bogus 5893 * length fields; our solution is to follow what 5894 * netlink_rcv_skb() does and simply skip processing at 5895 * messages with length fields that are clearly junk 5896 */ 5897 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5898 return 0; 5899 5900 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5901 if (rc == 0) { 5902 rc = sock_has_perm(sk, perm); 5903 if (rc) 5904 return rc; 5905 } else if (rc == -EINVAL) { 5906 /* -EINVAL is a missing msg/perm mapping */ 5907 pr_warn_ratelimited("SELinux: unrecognized netlink" 5908 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5909 " pid=%d comm=%s\n", 5910 sk->sk_protocol, nlh->nlmsg_type, 5911 secclass_map[sclass - 1].name, 5912 task_pid_nr(current), current->comm); 5913 if (enforcing_enabled() && 5914 !security_get_allow_unknown()) 5915 return rc; 5916 rc = 0; 5917 } else if (rc == -ENOENT) { 5918 /* -ENOENT is a missing socket/class mapping, ignore */ 5919 rc = 0; 5920 } else { 5921 return rc; 5922 } 5923 5924 /* move to the next message after applying netlink padding */ 5925 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5926 if (msg_len >= data_len) 5927 return 0; 5928 data_len -= msg_len; 5929 data += msg_len; 5930 } 5931 5932 return rc; 5933 } 5934 5935 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5936 { 5937 isec->sclass = sclass; 5938 isec->sid = current_sid(); 5939 } 5940 5941 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5942 u32 perms) 5943 { 5944 struct ipc_security_struct *isec; 5945 struct common_audit_data ad; 5946 u32 sid = current_sid(); 5947 5948 isec = selinux_ipc(ipc_perms); 5949 5950 ad.type = LSM_AUDIT_DATA_IPC; 5951 ad.u.ipc_id = ipc_perms->key; 5952 5953 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 5954 } 5955 5956 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5957 { 5958 struct msg_security_struct *msec; 5959 5960 msec = selinux_msg_msg(msg); 5961 msec->sid = SECINITSID_UNLABELED; 5962 5963 return 0; 5964 } 5965 5966 /* message queue security operations */ 5967 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5968 { 5969 struct ipc_security_struct *isec; 5970 struct common_audit_data ad; 5971 u32 sid = current_sid(); 5972 5973 isec = selinux_ipc(msq); 5974 ipc_init_security(isec, SECCLASS_MSGQ); 5975 5976 ad.type = LSM_AUDIT_DATA_IPC; 5977 ad.u.ipc_id = msq->key; 5978 5979 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5980 MSGQ__CREATE, &ad); 5981 } 5982 5983 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 5984 { 5985 struct ipc_security_struct *isec; 5986 struct common_audit_data ad; 5987 u32 sid = current_sid(); 5988 5989 isec = selinux_ipc(msq); 5990 5991 ad.type = LSM_AUDIT_DATA_IPC; 5992 ad.u.ipc_id = msq->key; 5993 5994 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5995 MSGQ__ASSOCIATE, &ad); 5996 } 5997 5998 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 5999 { 6000 u32 perms; 6001 6002 switch (cmd) { 6003 case IPC_INFO: 6004 case MSG_INFO: 6005 /* No specific object, just general system-wide information. */ 6006 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6007 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6008 case IPC_STAT: 6009 case MSG_STAT: 6010 case MSG_STAT_ANY: 6011 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6012 break; 6013 case IPC_SET: 6014 perms = MSGQ__SETATTR; 6015 break; 6016 case IPC_RMID: 6017 perms = MSGQ__DESTROY; 6018 break; 6019 default: 6020 return 0; 6021 } 6022 6023 return ipc_has_perm(msq, perms); 6024 } 6025 6026 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6027 { 6028 struct ipc_security_struct *isec; 6029 struct msg_security_struct *msec; 6030 struct common_audit_data ad; 6031 u32 sid = current_sid(); 6032 int rc; 6033 6034 isec = selinux_ipc(msq); 6035 msec = selinux_msg_msg(msg); 6036 6037 /* 6038 * First time through, need to assign label to the message 6039 */ 6040 if (msec->sid == SECINITSID_UNLABELED) { 6041 /* 6042 * Compute new sid based on current process and 6043 * message queue this message will be stored in 6044 */ 6045 rc = security_transition_sid(sid, isec->sid, 6046 SECCLASS_MSG, NULL, &msec->sid); 6047 if (rc) 6048 return rc; 6049 } 6050 6051 ad.type = LSM_AUDIT_DATA_IPC; 6052 ad.u.ipc_id = msq->key; 6053 6054 /* Can this process write to the queue? */ 6055 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6056 MSGQ__WRITE, &ad); 6057 if (!rc) 6058 /* Can this process send the message */ 6059 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6060 MSG__SEND, &ad); 6061 if (!rc) 6062 /* Can the message be put in the queue? */ 6063 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6064 MSGQ__ENQUEUE, &ad); 6065 6066 return rc; 6067 } 6068 6069 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6070 struct task_struct *target, 6071 long type, int mode) 6072 { 6073 struct ipc_security_struct *isec; 6074 struct msg_security_struct *msec; 6075 struct common_audit_data ad; 6076 u32 sid = task_sid_obj(target); 6077 int rc; 6078 6079 isec = selinux_ipc(msq); 6080 msec = selinux_msg_msg(msg); 6081 6082 ad.type = LSM_AUDIT_DATA_IPC; 6083 ad.u.ipc_id = msq->key; 6084 6085 rc = avc_has_perm(sid, isec->sid, 6086 SECCLASS_MSGQ, MSGQ__READ, &ad); 6087 if (!rc) 6088 rc = avc_has_perm(sid, msec->sid, 6089 SECCLASS_MSG, MSG__RECEIVE, &ad); 6090 return rc; 6091 } 6092 6093 /* Shared Memory security operations */ 6094 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6095 { 6096 struct ipc_security_struct *isec; 6097 struct common_audit_data ad; 6098 u32 sid = current_sid(); 6099 6100 isec = selinux_ipc(shp); 6101 ipc_init_security(isec, SECCLASS_SHM); 6102 6103 ad.type = LSM_AUDIT_DATA_IPC; 6104 ad.u.ipc_id = shp->key; 6105 6106 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6107 SHM__CREATE, &ad); 6108 } 6109 6110 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6111 { 6112 struct ipc_security_struct *isec; 6113 struct common_audit_data ad; 6114 u32 sid = current_sid(); 6115 6116 isec = selinux_ipc(shp); 6117 6118 ad.type = LSM_AUDIT_DATA_IPC; 6119 ad.u.ipc_id = shp->key; 6120 6121 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6122 SHM__ASSOCIATE, &ad); 6123 } 6124 6125 /* Note, at this point, shp is locked down */ 6126 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6127 { 6128 u32 perms; 6129 6130 switch (cmd) { 6131 case IPC_INFO: 6132 case SHM_INFO: 6133 /* No specific object, just general system-wide information. */ 6134 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6135 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6136 case IPC_STAT: 6137 case SHM_STAT: 6138 case SHM_STAT_ANY: 6139 perms = SHM__GETATTR | SHM__ASSOCIATE; 6140 break; 6141 case IPC_SET: 6142 perms = SHM__SETATTR; 6143 break; 6144 case SHM_LOCK: 6145 case SHM_UNLOCK: 6146 perms = SHM__LOCK; 6147 break; 6148 case IPC_RMID: 6149 perms = SHM__DESTROY; 6150 break; 6151 default: 6152 return 0; 6153 } 6154 6155 return ipc_has_perm(shp, perms); 6156 } 6157 6158 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6159 char __user *shmaddr, int shmflg) 6160 { 6161 u32 perms; 6162 6163 if (shmflg & SHM_RDONLY) 6164 perms = SHM__READ; 6165 else 6166 perms = SHM__READ | SHM__WRITE; 6167 6168 return ipc_has_perm(shp, perms); 6169 } 6170 6171 /* Semaphore security operations */ 6172 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6173 { 6174 struct ipc_security_struct *isec; 6175 struct common_audit_data ad; 6176 u32 sid = current_sid(); 6177 6178 isec = selinux_ipc(sma); 6179 ipc_init_security(isec, SECCLASS_SEM); 6180 6181 ad.type = LSM_AUDIT_DATA_IPC; 6182 ad.u.ipc_id = sma->key; 6183 6184 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6185 SEM__CREATE, &ad); 6186 } 6187 6188 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6189 { 6190 struct ipc_security_struct *isec; 6191 struct common_audit_data ad; 6192 u32 sid = current_sid(); 6193 6194 isec = selinux_ipc(sma); 6195 6196 ad.type = LSM_AUDIT_DATA_IPC; 6197 ad.u.ipc_id = sma->key; 6198 6199 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6200 SEM__ASSOCIATE, &ad); 6201 } 6202 6203 /* Note, at this point, sma is locked down */ 6204 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6205 { 6206 int err; 6207 u32 perms; 6208 6209 switch (cmd) { 6210 case IPC_INFO: 6211 case SEM_INFO: 6212 /* No specific object, just general system-wide information. */ 6213 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6214 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6215 case GETPID: 6216 case GETNCNT: 6217 case GETZCNT: 6218 perms = SEM__GETATTR; 6219 break; 6220 case GETVAL: 6221 case GETALL: 6222 perms = SEM__READ; 6223 break; 6224 case SETVAL: 6225 case SETALL: 6226 perms = SEM__WRITE; 6227 break; 6228 case IPC_RMID: 6229 perms = SEM__DESTROY; 6230 break; 6231 case IPC_SET: 6232 perms = SEM__SETATTR; 6233 break; 6234 case IPC_STAT: 6235 case SEM_STAT: 6236 case SEM_STAT_ANY: 6237 perms = SEM__GETATTR | SEM__ASSOCIATE; 6238 break; 6239 default: 6240 return 0; 6241 } 6242 6243 err = ipc_has_perm(sma, perms); 6244 return err; 6245 } 6246 6247 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6248 struct sembuf *sops, unsigned nsops, int alter) 6249 { 6250 u32 perms; 6251 6252 if (alter) 6253 perms = SEM__READ | SEM__WRITE; 6254 else 6255 perms = SEM__READ; 6256 6257 return ipc_has_perm(sma, perms); 6258 } 6259 6260 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6261 { 6262 u32 av = 0; 6263 6264 av = 0; 6265 if (flag & S_IRUGO) 6266 av |= IPC__UNIX_READ; 6267 if (flag & S_IWUGO) 6268 av |= IPC__UNIX_WRITE; 6269 6270 if (av == 0) 6271 return 0; 6272 6273 return ipc_has_perm(ipcp, av); 6274 } 6275 6276 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6277 { 6278 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6279 *secid = isec->sid; 6280 } 6281 6282 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6283 { 6284 if (inode) 6285 inode_doinit_with_dentry(inode, dentry); 6286 } 6287 6288 static int selinux_getprocattr(struct task_struct *p, 6289 const char *name, char **value) 6290 { 6291 const struct task_security_struct *__tsec; 6292 u32 sid; 6293 int error; 6294 unsigned len; 6295 6296 rcu_read_lock(); 6297 __tsec = selinux_cred(__task_cred(p)); 6298 6299 if (current != p) { 6300 error = avc_has_perm(current_sid(), __tsec->sid, 6301 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6302 if (error) 6303 goto bad; 6304 } 6305 6306 if (!strcmp(name, "current")) 6307 sid = __tsec->sid; 6308 else if (!strcmp(name, "prev")) 6309 sid = __tsec->osid; 6310 else if (!strcmp(name, "exec")) 6311 sid = __tsec->exec_sid; 6312 else if (!strcmp(name, "fscreate")) 6313 sid = __tsec->create_sid; 6314 else if (!strcmp(name, "keycreate")) 6315 sid = __tsec->keycreate_sid; 6316 else if (!strcmp(name, "sockcreate")) 6317 sid = __tsec->sockcreate_sid; 6318 else { 6319 error = -EINVAL; 6320 goto bad; 6321 } 6322 rcu_read_unlock(); 6323 6324 if (!sid) 6325 return 0; 6326 6327 error = security_sid_to_context(sid, value, &len); 6328 if (error) 6329 return error; 6330 return len; 6331 6332 bad: 6333 rcu_read_unlock(); 6334 return error; 6335 } 6336 6337 static int selinux_setprocattr(const char *name, void *value, size_t size) 6338 { 6339 struct task_security_struct *tsec; 6340 struct cred *new; 6341 u32 mysid = current_sid(), sid = 0, ptsid; 6342 int error; 6343 char *str = value; 6344 6345 /* 6346 * Basic control over ability to set these attributes at all. 6347 */ 6348 if (!strcmp(name, "exec")) 6349 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6350 PROCESS__SETEXEC, NULL); 6351 else if (!strcmp(name, "fscreate")) 6352 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6353 PROCESS__SETFSCREATE, NULL); 6354 else if (!strcmp(name, "keycreate")) 6355 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6356 PROCESS__SETKEYCREATE, NULL); 6357 else if (!strcmp(name, "sockcreate")) 6358 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6359 PROCESS__SETSOCKCREATE, NULL); 6360 else if (!strcmp(name, "current")) 6361 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6362 PROCESS__SETCURRENT, NULL); 6363 else 6364 error = -EINVAL; 6365 if (error) 6366 return error; 6367 6368 /* Obtain a SID for the context, if one was specified. */ 6369 if (size && str[0] && str[0] != '\n') { 6370 if (str[size-1] == '\n') { 6371 str[size-1] = 0; 6372 size--; 6373 } 6374 error = security_context_to_sid(value, size, 6375 &sid, GFP_KERNEL); 6376 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6377 if (!has_cap_mac_admin(true)) { 6378 struct audit_buffer *ab; 6379 size_t audit_size; 6380 6381 /* We strip a nul only if it is at the end, otherwise the 6382 * context contains a nul and we should audit that */ 6383 if (str[size - 1] == '\0') 6384 audit_size = size - 1; 6385 else 6386 audit_size = size; 6387 ab = audit_log_start(audit_context(), 6388 GFP_ATOMIC, 6389 AUDIT_SELINUX_ERR); 6390 if (!ab) 6391 return error; 6392 audit_log_format(ab, "op=fscreate invalid_context="); 6393 audit_log_n_untrustedstring(ab, value, audit_size); 6394 audit_log_end(ab); 6395 6396 return error; 6397 } 6398 error = security_context_to_sid_force(value, size, 6399 &sid); 6400 } 6401 if (error) 6402 return error; 6403 } 6404 6405 new = prepare_creds(); 6406 if (!new) 6407 return -ENOMEM; 6408 6409 /* Permission checking based on the specified context is 6410 performed during the actual operation (execve, 6411 open/mkdir/...), when we know the full context of the 6412 operation. See selinux_bprm_creds_for_exec for the execve 6413 checks and may_create for the file creation checks. The 6414 operation will then fail if the context is not permitted. */ 6415 tsec = selinux_cred(new); 6416 if (!strcmp(name, "exec")) { 6417 tsec->exec_sid = sid; 6418 } else if (!strcmp(name, "fscreate")) { 6419 tsec->create_sid = sid; 6420 } else if (!strcmp(name, "keycreate")) { 6421 if (sid) { 6422 error = avc_has_perm(mysid, sid, 6423 SECCLASS_KEY, KEY__CREATE, NULL); 6424 if (error) 6425 goto abort_change; 6426 } 6427 tsec->keycreate_sid = sid; 6428 } else if (!strcmp(name, "sockcreate")) { 6429 tsec->sockcreate_sid = sid; 6430 } else if (!strcmp(name, "current")) { 6431 error = -EINVAL; 6432 if (sid == 0) 6433 goto abort_change; 6434 6435 /* Only allow single threaded processes to change context */ 6436 if (!current_is_single_threaded()) { 6437 error = security_bounded_transition(tsec->sid, sid); 6438 if (error) 6439 goto abort_change; 6440 } 6441 6442 /* Check permissions for the transition. */ 6443 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6444 PROCESS__DYNTRANSITION, NULL); 6445 if (error) 6446 goto abort_change; 6447 6448 /* Check for ptracing, and update the task SID if ok. 6449 Otherwise, leave SID unchanged and fail. */ 6450 ptsid = ptrace_parent_sid(); 6451 if (ptsid != 0) { 6452 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6453 PROCESS__PTRACE, NULL); 6454 if (error) 6455 goto abort_change; 6456 } 6457 6458 tsec->sid = sid; 6459 } else { 6460 error = -EINVAL; 6461 goto abort_change; 6462 } 6463 6464 commit_creds(new); 6465 return size; 6466 6467 abort_change: 6468 abort_creds(new); 6469 return error; 6470 } 6471 6472 static int selinux_ismaclabel(const char *name) 6473 { 6474 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6475 } 6476 6477 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6478 { 6479 return security_sid_to_context(secid, 6480 secdata, seclen); 6481 } 6482 6483 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6484 { 6485 return security_context_to_sid(secdata, seclen, 6486 secid, GFP_KERNEL); 6487 } 6488 6489 static void selinux_release_secctx(char *secdata, u32 seclen) 6490 { 6491 kfree(secdata); 6492 } 6493 6494 static void selinux_inode_invalidate_secctx(struct inode *inode) 6495 { 6496 struct inode_security_struct *isec = selinux_inode(inode); 6497 6498 spin_lock(&isec->lock); 6499 isec->initialized = LABEL_INVALID; 6500 spin_unlock(&isec->lock); 6501 } 6502 6503 /* 6504 * called with inode->i_mutex locked 6505 */ 6506 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6507 { 6508 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6509 ctx, ctxlen, 0); 6510 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6511 return rc == -EOPNOTSUPP ? 0 : rc; 6512 } 6513 6514 /* 6515 * called with inode->i_mutex locked 6516 */ 6517 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6518 { 6519 return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6520 ctx, ctxlen, 0); 6521 } 6522 6523 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6524 { 6525 int len = 0; 6526 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6527 XATTR_SELINUX_SUFFIX, ctx, true); 6528 if (len < 0) 6529 return len; 6530 *ctxlen = len; 6531 return 0; 6532 } 6533 #ifdef CONFIG_KEYS 6534 6535 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6536 unsigned long flags) 6537 { 6538 const struct task_security_struct *tsec; 6539 struct key_security_struct *ksec; 6540 6541 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6542 if (!ksec) 6543 return -ENOMEM; 6544 6545 tsec = selinux_cred(cred); 6546 if (tsec->keycreate_sid) 6547 ksec->sid = tsec->keycreate_sid; 6548 else 6549 ksec->sid = tsec->sid; 6550 6551 k->security = ksec; 6552 return 0; 6553 } 6554 6555 static void selinux_key_free(struct key *k) 6556 { 6557 struct key_security_struct *ksec = k->security; 6558 6559 k->security = NULL; 6560 kfree(ksec); 6561 } 6562 6563 static int selinux_key_permission(key_ref_t key_ref, 6564 const struct cred *cred, 6565 enum key_need_perm need_perm) 6566 { 6567 struct key *key; 6568 struct key_security_struct *ksec; 6569 u32 perm, sid; 6570 6571 switch (need_perm) { 6572 case KEY_NEED_VIEW: 6573 perm = KEY__VIEW; 6574 break; 6575 case KEY_NEED_READ: 6576 perm = KEY__READ; 6577 break; 6578 case KEY_NEED_WRITE: 6579 perm = KEY__WRITE; 6580 break; 6581 case KEY_NEED_SEARCH: 6582 perm = KEY__SEARCH; 6583 break; 6584 case KEY_NEED_LINK: 6585 perm = KEY__LINK; 6586 break; 6587 case KEY_NEED_SETATTR: 6588 perm = KEY__SETATTR; 6589 break; 6590 case KEY_NEED_UNLINK: 6591 case KEY_SYSADMIN_OVERRIDE: 6592 case KEY_AUTHTOKEN_OVERRIDE: 6593 case KEY_DEFER_PERM_CHECK: 6594 return 0; 6595 default: 6596 WARN_ON(1); 6597 return -EPERM; 6598 6599 } 6600 6601 sid = cred_sid(cred); 6602 key = key_ref_to_ptr(key_ref); 6603 ksec = key->security; 6604 6605 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6606 } 6607 6608 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6609 { 6610 struct key_security_struct *ksec = key->security; 6611 char *context = NULL; 6612 unsigned len; 6613 int rc; 6614 6615 rc = security_sid_to_context(ksec->sid, 6616 &context, &len); 6617 if (!rc) 6618 rc = len; 6619 *_buffer = context; 6620 return rc; 6621 } 6622 6623 #ifdef CONFIG_KEY_NOTIFICATIONS 6624 static int selinux_watch_key(struct key *key) 6625 { 6626 struct key_security_struct *ksec = key->security; 6627 u32 sid = current_sid(); 6628 6629 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6630 } 6631 #endif 6632 #endif 6633 6634 #ifdef CONFIG_SECURITY_INFINIBAND 6635 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6636 { 6637 struct common_audit_data ad; 6638 int err; 6639 u32 sid = 0; 6640 struct ib_security_struct *sec = ib_sec; 6641 struct lsm_ibpkey_audit ibpkey; 6642 6643 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6644 if (err) 6645 return err; 6646 6647 ad.type = LSM_AUDIT_DATA_IBPKEY; 6648 ibpkey.subnet_prefix = subnet_prefix; 6649 ibpkey.pkey = pkey_val; 6650 ad.u.ibpkey = &ibpkey; 6651 return avc_has_perm(sec->sid, sid, 6652 SECCLASS_INFINIBAND_PKEY, 6653 INFINIBAND_PKEY__ACCESS, &ad); 6654 } 6655 6656 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6657 u8 port_num) 6658 { 6659 struct common_audit_data ad; 6660 int err; 6661 u32 sid = 0; 6662 struct ib_security_struct *sec = ib_sec; 6663 struct lsm_ibendport_audit ibendport; 6664 6665 err = security_ib_endport_sid(dev_name, port_num, 6666 &sid); 6667 6668 if (err) 6669 return err; 6670 6671 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6672 ibendport.dev_name = dev_name; 6673 ibendport.port = port_num; 6674 ad.u.ibendport = &ibendport; 6675 return avc_has_perm(sec->sid, sid, 6676 SECCLASS_INFINIBAND_ENDPORT, 6677 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6678 } 6679 6680 static int selinux_ib_alloc_security(void **ib_sec) 6681 { 6682 struct ib_security_struct *sec; 6683 6684 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6685 if (!sec) 6686 return -ENOMEM; 6687 sec->sid = current_sid(); 6688 6689 *ib_sec = sec; 6690 return 0; 6691 } 6692 6693 static void selinux_ib_free_security(void *ib_sec) 6694 { 6695 kfree(ib_sec); 6696 } 6697 #endif 6698 6699 #ifdef CONFIG_BPF_SYSCALL 6700 static int selinux_bpf(int cmd, union bpf_attr *attr, 6701 unsigned int size) 6702 { 6703 u32 sid = current_sid(); 6704 int ret; 6705 6706 switch (cmd) { 6707 case BPF_MAP_CREATE: 6708 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6709 NULL); 6710 break; 6711 case BPF_PROG_LOAD: 6712 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6713 NULL); 6714 break; 6715 default: 6716 ret = 0; 6717 break; 6718 } 6719 6720 return ret; 6721 } 6722 6723 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6724 { 6725 u32 av = 0; 6726 6727 if (fmode & FMODE_READ) 6728 av |= BPF__MAP_READ; 6729 if (fmode & FMODE_WRITE) 6730 av |= BPF__MAP_WRITE; 6731 return av; 6732 } 6733 6734 /* This function will check the file pass through unix socket or binder to see 6735 * if it is a bpf related object. And apply corresponding checks on the bpf 6736 * object based on the type. The bpf maps and programs, not like other files and 6737 * socket, are using a shared anonymous inode inside the kernel as their inode. 6738 * So checking that inode cannot identify if the process have privilege to 6739 * access the bpf object and that's why we have to add this additional check in 6740 * selinux_file_receive and selinux_binder_transfer_files. 6741 */ 6742 static int bpf_fd_pass(const struct file *file, u32 sid) 6743 { 6744 struct bpf_security_struct *bpfsec; 6745 struct bpf_prog *prog; 6746 struct bpf_map *map; 6747 int ret; 6748 6749 if (file->f_op == &bpf_map_fops) { 6750 map = file->private_data; 6751 bpfsec = map->security; 6752 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6753 bpf_map_fmode_to_av(file->f_mode), NULL); 6754 if (ret) 6755 return ret; 6756 } else if (file->f_op == &bpf_prog_fops) { 6757 prog = file->private_data; 6758 bpfsec = prog->aux->security; 6759 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6760 BPF__PROG_RUN, NULL); 6761 if (ret) 6762 return ret; 6763 } 6764 return 0; 6765 } 6766 6767 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6768 { 6769 u32 sid = current_sid(); 6770 struct bpf_security_struct *bpfsec; 6771 6772 bpfsec = map->security; 6773 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6774 bpf_map_fmode_to_av(fmode), NULL); 6775 } 6776 6777 static int selinux_bpf_prog(struct bpf_prog *prog) 6778 { 6779 u32 sid = current_sid(); 6780 struct bpf_security_struct *bpfsec; 6781 6782 bpfsec = prog->aux->security; 6783 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6784 BPF__PROG_RUN, NULL); 6785 } 6786 6787 static int selinux_bpf_map_alloc(struct bpf_map *map) 6788 { 6789 struct bpf_security_struct *bpfsec; 6790 6791 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6792 if (!bpfsec) 6793 return -ENOMEM; 6794 6795 bpfsec->sid = current_sid(); 6796 map->security = bpfsec; 6797 6798 return 0; 6799 } 6800 6801 static void selinux_bpf_map_free(struct bpf_map *map) 6802 { 6803 struct bpf_security_struct *bpfsec = map->security; 6804 6805 map->security = NULL; 6806 kfree(bpfsec); 6807 } 6808 6809 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6810 { 6811 struct bpf_security_struct *bpfsec; 6812 6813 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6814 if (!bpfsec) 6815 return -ENOMEM; 6816 6817 bpfsec->sid = current_sid(); 6818 aux->security = bpfsec; 6819 6820 return 0; 6821 } 6822 6823 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6824 { 6825 struct bpf_security_struct *bpfsec = aux->security; 6826 6827 aux->security = NULL; 6828 kfree(bpfsec); 6829 } 6830 #endif 6831 6832 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 6833 .lbs_cred = sizeof(struct task_security_struct), 6834 .lbs_file = sizeof(struct file_security_struct), 6835 .lbs_inode = sizeof(struct inode_security_struct), 6836 .lbs_ipc = sizeof(struct ipc_security_struct), 6837 .lbs_msg_msg = sizeof(struct msg_security_struct), 6838 .lbs_superblock = sizeof(struct superblock_security_struct), 6839 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 6840 }; 6841 6842 #ifdef CONFIG_PERF_EVENTS 6843 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6844 { 6845 u32 requested, sid = current_sid(); 6846 6847 if (type == PERF_SECURITY_OPEN) 6848 requested = PERF_EVENT__OPEN; 6849 else if (type == PERF_SECURITY_CPU) 6850 requested = PERF_EVENT__CPU; 6851 else if (type == PERF_SECURITY_KERNEL) 6852 requested = PERF_EVENT__KERNEL; 6853 else if (type == PERF_SECURITY_TRACEPOINT) 6854 requested = PERF_EVENT__TRACEPOINT; 6855 else 6856 return -EINVAL; 6857 6858 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 6859 requested, NULL); 6860 } 6861 6862 static int selinux_perf_event_alloc(struct perf_event *event) 6863 { 6864 struct perf_event_security_struct *perfsec; 6865 6866 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6867 if (!perfsec) 6868 return -ENOMEM; 6869 6870 perfsec->sid = current_sid(); 6871 event->security = perfsec; 6872 6873 return 0; 6874 } 6875 6876 static void selinux_perf_event_free(struct perf_event *event) 6877 { 6878 struct perf_event_security_struct *perfsec = event->security; 6879 6880 event->security = NULL; 6881 kfree(perfsec); 6882 } 6883 6884 static int selinux_perf_event_read(struct perf_event *event) 6885 { 6886 struct perf_event_security_struct *perfsec = event->security; 6887 u32 sid = current_sid(); 6888 6889 return avc_has_perm(sid, perfsec->sid, 6890 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6891 } 6892 6893 static int selinux_perf_event_write(struct perf_event *event) 6894 { 6895 struct perf_event_security_struct *perfsec = event->security; 6896 u32 sid = current_sid(); 6897 6898 return avc_has_perm(sid, perfsec->sid, 6899 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6900 } 6901 #endif 6902 6903 #ifdef CONFIG_IO_URING 6904 /** 6905 * selinux_uring_override_creds - check the requested cred override 6906 * @new: the target creds 6907 * 6908 * Check to see if the current task is allowed to override it's credentials 6909 * to service an io_uring operation. 6910 */ 6911 static int selinux_uring_override_creds(const struct cred *new) 6912 { 6913 return avc_has_perm(current_sid(), cred_sid(new), 6914 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 6915 } 6916 6917 /** 6918 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 6919 * 6920 * Check to see if the current task is allowed to create a new io_uring 6921 * kernel polling thread. 6922 */ 6923 static int selinux_uring_sqpoll(void) 6924 { 6925 u32 sid = current_sid(); 6926 6927 return avc_has_perm(sid, sid, 6928 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 6929 } 6930 6931 /** 6932 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 6933 * @ioucmd: the io_uring command structure 6934 * 6935 * Check to see if the current domain is allowed to execute an 6936 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 6937 * 6938 */ 6939 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 6940 { 6941 struct file *file = ioucmd->file; 6942 struct inode *inode = file_inode(file); 6943 struct inode_security_struct *isec = selinux_inode(inode); 6944 struct common_audit_data ad; 6945 6946 ad.type = LSM_AUDIT_DATA_FILE; 6947 ad.u.file = file; 6948 6949 return avc_has_perm(current_sid(), isec->sid, 6950 SECCLASS_IO_URING, IO_URING__CMD, &ad); 6951 } 6952 #endif /* CONFIG_IO_URING */ 6953 6954 const struct lsm_id selinux_lsmid = { 6955 .name = "selinux", 6956 .id = LSM_ID_SELINUX, 6957 }; 6958 6959 /* 6960 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6961 * 1. any hooks that don't belong to (2.) or (3.) below, 6962 * 2. hooks that both access structures allocated by other hooks, and allocate 6963 * structures that can be later accessed by other hooks (mostly "cloning" 6964 * hooks), 6965 * 3. hooks that only allocate structures that can be later accessed by other 6966 * hooks ("allocating" hooks). 6967 * 6968 * Please follow block comment delimiters in the list to keep this order. 6969 */ 6970 static struct security_hook_list selinux_hooks[] __ro_after_init = { 6971 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6972 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6973 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6974 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6975 6976 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6977 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6978 LSM_HOOK_INIT(capget, selinux_capget), 6979 LSM_HOOK_INIT(capset, selinux_capset), 6980 LSM_HOOK_INIT(capable, selinux_capable), 6981 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6982 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6983 LSM_HOOK_INIT(syslog, selinux_syslog), 6984 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6985 6986 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6987 6988 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 6989 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6990 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6991 6992 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 6993 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 6994 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6995 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6996 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6997 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6998 LSM_HOOK_INIT(sb_mount, selinux_mount), 6999 LSM_HOOK_INIT(sb_umount, selinux_umount), 7000 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7001 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7002 7003 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7004 7005 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7006 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7007 7008 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7009 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7010 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7011 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7012 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7013 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7014 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7015 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7016 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7017 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7018 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7019 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7020 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7021 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7022 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7023 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7024 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7025 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7026 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7027 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7028 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7029 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7030 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7031 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7032 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7033 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7034 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7035 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7036 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7037 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7038 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7039 7040 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7041 7042 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7043 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7044 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7045 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7046 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7047 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7048 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7049 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7050 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7051 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7052 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7053 7054 LSM_HOOK_INIT(file_open, selinux_file_open), 7055 7056 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7057 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7058 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7059 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7060 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7061 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7062 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7063 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7064 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7065 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7066 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7067 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7068 LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), 7069 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), 7070 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7071 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7072 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7073 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7074 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7075 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7076 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7077 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7078 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7079 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7080 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7081 7082 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7083 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7084 7085 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7086 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7087 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7088 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7089 7090 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7091 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7092 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7093 7094 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7095 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7096 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7097 7098 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7099 7100 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7101 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7102 7103 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7104 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7105 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7106 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7107 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7108 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7109 7110 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7111 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7112 7113 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7114 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7115 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7116 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7117 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7118 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7119 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7120 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7121 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7122 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7123 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7124 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7125 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7126 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7127 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7128 LSM_HOOK_INIT(socket_getpeersec_stream, 7129 selinux_socket_getpeersec_stream), 7130 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7131 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7132 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7133 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7134 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7135 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7136 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7137 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7138 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7139 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7140 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7141 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7142 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7143 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7144 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7145 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7146 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7147 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7148 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7149 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7150 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7151 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7152 #ifdef CONFIG_SECURITY_INFINIBAND 7153 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7154 LSM_HOOK_INIT(ib_endport_manage_subnet, 7155 selinux_ib_endport_manage_subnet), 7156 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7157 #endif 7158 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7159 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7160 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7161 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7162 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7163 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7164 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7165 selinux_xfrm_state_pol_flow_match), 7166 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7167 #endif 7168 7169 #ifdef CONFIG_KEYS 7170 LSM_HOOK_INIT(key_free, selinux_key_free), 7171 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7172 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7173 #ifdef CONFIG_KEY_NOTIFICATIONS 7174 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7175 #endif 7176 #endif 7177 7178 #ifdef CONFIG_AUDIT 7179 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7180 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7181 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7182 #endif 7183 7184 #ifdef CONFIG_BPF_SYSCALL 7185 LSM_HOOK_INIT(bpf, selinux_bpf), 7186 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7187 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7188 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7189 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7190 #endif 7191 7192 #ifdef CONFIG_PERF_EVENTS 7193 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7194 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7195 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7196 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7197 #endif 7198 7199 #ifdef CONFIG_IO_URING 7200 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7201 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7202 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7203 #endif 7204 7205 /* 7206 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7207 */ 7208 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7209 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7210 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7211 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7212 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7213 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7214 #endif 7215 7216 /* 7217 * PUT "ALLOCATING" HOOKS HERE 7218 */ 7219 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7220 LSM_HOOK_INIT(msg_queue_alloc_security, 7221 selinux_msg_queue_alloc_security), 7222 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7223 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7224 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7225 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7226 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7227 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7228 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7229 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7230 #ifdef CONFIG_SECURITY_INFINIBAND 7231 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7232 #endif 7233 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7234 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7235 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7236 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7237 selinux_xfrm_state_alloc_acquire), 7238 #endif 7239 #ifdef CONFIG_KEYS 7240 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7241 #endif 7242 #ifdef CONFIG_AUDIT 7243 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7244 #endif 7245 #ifdef CONFIG_BPF_SYSCALL 7246 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7247 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7248 #endif 7249 #ifdef CONFIG_PERF_EVENTS 7250 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7251 #endif 7252 }; 7253 7254 static __init int selinux_init(void) 7255 { 7256 pr_info("SELinux: Initializing.\n"); 7257 7258 memset(&selinux_state, 0, sizeof(selinux_state)); 7259 enforcing_set(selinux_enforcing_boot); 7260 selinux_avc_init(); 7261 mutex_init(&selinux_state.status_lock); 7262 mutex_init(&selinux_state.policy_mutex); 7263 7264 /* Set the security state for the initial task. */ 7265 cred_init_security(); 7266 7267 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7268 if (!default_noexec) 7269 pr_notice("SELinux: virtual memory is executable by default\n"); 7270 7271 avc_init(); 7272 7273 avtab_cache_init(); 7274 7275 ebitmap_cache_init(); 7276 7277 hashtab_cache_init(); 7278 7279 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), 7280 &selinux_lsmid); 7281 7282 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7283 panic("SELinux: Unable to register AVC netcache callback\n"); 7284 7285 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7286 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7287 7288 if (selinux_enforcing_boot) 7289 pr_debug("SELinux: Starting in enforcing mode\n"); 7290 else 7291 pr_debug("SELinux: Starting in permissive mode\n"); 7292 7293 fs_validate_description("selinux", selinux_fs_parameters); 7294 7295 return 0; 7296 } 7297 7298 static void delayed_superblock_init(struct super_block *sb, void *unused) 7299 { 7300 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7301 } 7302 7303 void selinux_complete_init(void) 7304 { 7305 pr_debug("SELinux: Completing initialization.\n"); 7306 7307 /* Set up any superblocks initialized prior to the policy load. */ 7308 pr_debug("SELinux: Setting up existing superblocks.\n"); 7309 iterate_supers(delayed_superblock_init, NULL); 7310 } 7311 7312 /* SELinux requires early initialization in order to label 7313 all processes and objects when they are created. */ 7314 DEFINE_LSM(selinux) = { 7315 .name = "selinux", 7316 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7317 .enabled = &selinux_enabled_boot, 7318 .blobs = &selinux_blob_sizes, 7319 .init = selinux_init, 7320 }; 7321 7322 #if defined(CONFIG_NETFILTER) 7323 static const struct nf_hook_ops selinux_nf_ops[] = { 7324 { 7325 .hook = selinux_ip_postroute, 7326 .pf = NFPROTO_IPV4, 7327 .hooknum = NF_INET_POST_ROUTING, 7328 .priority = NF_IP_PRI_SELINUX_LAST, 7329 }, 7330 { 7331 .hook = selinux_ip_forward, 7332 .pf = NFPROTO_IPV4, 7333 .hooknum = NF_INET_FORWARD, 7334 .priority = NF_IP_PRI_SELINUX_FIRST, 7335 }, 7336 { 7337 .hook = selinux_ip_output, 7338 .pf = NFPROTO_IPV4, 7339 .hooknum = NF_INET_LOCAL_OUT, 7340 .priority = NF_IP_PRI_SELINUX_FIRST, 7341 }, 7342 #if IS_ENABLED(CONFIG_IPV6) 7343 { 7344 .hook = selinux_ip_postroute, 7345 .pf = NFPROTO_IPV6, 7346 .hooknum = NF_INET_POST_ROUTING, 7347 .priority = NF_IP6_PRI_SELINUX_LAST, 7348 }, 7349 { 7350 .hook = selinux_ip_forward, 7351 .pf = NFPROTO_IPV6, 7352 .hooknum = NF_INET_FORWARD, 7353 .priority = NF_IP6_PRI_SELINUX_FIRST, 7354 }, 7355 { 7356 .hook = selinux_ip_output, 7357 .pf = NFPROTO_IPV6, 7358 .hooknum = NF_INET_LOCAL_OUT, 7359 .priority = NF_IP6_PRI_SELINUX_FIRST, 7360 }, 7361 #endif /* IPV6 */ 7362 }; 7363 7364 static int __net_init selinux_nf_register(struct net *net) 7365 { 7366 return nf_register_net_hooks(net, selinux_nf_ops, 7367 ARRAY_SIZE(selinux_nf_ops)); 7368 } 7369 7370 static void __net_exit selinux_nf_unregister(struct net *net) 7371 { 7372 nf_unregister_net_hooks(net, selinux_nf_ops, 7373 ARRAY_SIZE(selinux_nf_ops)); 7374 } 7375 7376 static struct pernet_operations selinux_net_ops = { 7377 .init = selinux_nf_register, 7378 .exit = selinux_nf_unregister, 7379 }; 7380 7381 static int __init selinux_nf_ip_init(void) 7382 { 7383 int err; 7384 7385 if (!selinux_enabled_boot) 7386 return 0; 7387 7388 pr_debug("SELinux: Registering netfilter hooks\n"); 7389 7390 err = register_pernet_subsys(&selinux_net_ops); 7391 if (err) 7392 panic("SELinux: register_pernet_subsys: error %d\n", err); 7393 7394 return 0; 7395 } 7396 __initcall(selinux_nf_ip_init); 7397 #endif /* CONFIG_NETFILTER */ 7398