1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Security-Enhanced Linux (SELinux) security module 4 * 5 * This file contains the SELinux hook function implementations. 6 * 7 * Authors: Stephen Smalley, <stephen.smalley.work@gmail.com> 8 * Chris Vance, <cvance@nai.com> 9 * Wayne Salamon, <wsalamon@nai.com> 10 * James Morris <jmorris@redhat.com> 11 * 12 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 13 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> 14 * Eric Paris <eparis@redhat.com> 15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 16 * <dgoeddel@trustedcs.com> 17 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. 18 * Paul Moore <paul@paul-moore.com> 19 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 20 * Yuichi Nakamura <ynakam@hitachisoft.jp> 21 * Copyright (C) 2016 Mellanox Technologies 22 */ 23 24 #include <linux/init.h> 25 #include <linux/kd.h> 26 #include <linux/kernel.h> 27 #include <linux/kernel_read_file.h> 28 #include <linux/errno.h> 29 #include <linux/sched/signal.h> 30 #include <linux/sched/task.h> 31 #include <linux/lsm_hooks.h> 32 #include <linux/xattr.h> 33 #include <linux/capability.h> 34 #include <linux/unistd.h> 35 #include <linux/mm.h> 36 #include <linux/mman.h> 37 #include <linux/slab.h> 38 #include <linux/pagemap.h> 39 #include <linux/proc_fs.h> 40 #include <linux/swap.h> 41 #include <linux/spinlock.h> 42 #include <linux/syscalls.h> 43 #include <linux/dcache.h> 44 #include <linux/file.h> 45 #include <linux/fdtable.h> 46 #include <linux/namei.h> 47 #include <linux/mount.h> 48 #include <linux/fs_context.h> 49 #include <linux/fs_parser.h> 50 #include <linux/netfilter_ipv4.h> 51 #include <linux/netfilter_ipv6.h> 52 #include <linux/tty.h> 53 #include <net/icmp.h> 54 #include <net/ip.h> /* for local_port_range[] */ 55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 56 #include <net/inet_connection_sock.h> 57 #include <net/net_namespace.h> 58 #include <net/netlabel.h> 59 #include <linux/uaccess.h> 60 #include <asm/ioctls.h> 61 #include <linux/atomic.h> 62 #include <linux/bitops.h> 63 #include <linux/interrupt.h> 64 #include <linux/netdevice.h> /* for network interface checks */ 65 #include <net/netlink.h> 66 #include <linux/tcp.h> 67 #include <linux/udp.h> 68 #include <linux/dccp.h> 69 #include <linux/sctp.h> 70 #include <net/sctp/structs.h> 71 #include <linux/quota.h> 72 #include <linux/un.h> /* for Unix socket types */ 73 #include <net/af_unix.h> /* for Unix socket types */ 74 #include <linux/parser.h> 75 #include <linux/nfs_mount.h> 76 #include <net/ipv6.h> 77 #include <linux/hugetlb.h> 78 #include <linux/personality.h> 79 #include <linux/audit.h> 80 #include <linux/string.h> 81 #include <linux/mutex.h> 82 #include <linux/posix-timers.h> 83 #include <linux/syslog.h> 84 #include <linux/user_namespace.h> 85 #include <linux/export.h> 86 #include <linux/msg.h> 87 #include <linux/shm.h> 88 #include <linux/bpf.h> 89 #include <linux/kernfs.h> 90 #include <linux/stringhash.h> /* for hashlen_string() */ 91 #include <uapi/linux/mount.h> 92 #include <linux/fsnotify.h> 93 #include <linux/fanotify.h> 94 #include <linux/io_uring.h> 95 96 #include "avc.h" 97 #include "objsec.h" 98 #include "netif.h" 99 #include "netnode.h" 100 #include "netport.h" 101 #include "ibpkey.h" 102 #include "xfrm.h" 103 #include "netlabel.h" 104 #include "audit.h" 105 #include "avc_ss.h" 106 107 #define SELINUX_INODE_INIT_XATTRS 1 108 109 struct selinux_state selinux_state; 110 111 /* SECMARK reference count */ 112 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 113 114 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 115 static int selinux_enforcing_boot __initdata; 116 117 static int __init enforcing_setup(char *str) 118 { 119 unsigned long enforcing; 120 if (!kstrtoul(str, 0, &enforcing)) 121 selinux_enforcing_boot = enforcing ? 1 : 0; 122 return 1; 123 } 124 __setup("enforcing=", enforcing_setup); 125 #else 126 #define selinux_enforcing_boot 1 127 #endif 128 129 int selinux_enabled_boot __initdata = 1; 130 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 131 static int __init selinux_enabled_setup(char *str) 132 { 133 unsigned long enabled; 134 if (!kstrtoul(str, 0, &enabled)) 135 selinux_enabled_boot = enabled ? 1 : 0; 136 return 1; 137 } 138 __setup("selinux=", selinux_enabled_setup); 139 #endif 140 141 static int __init checkreqprot_setup(char *str) 142 { 143 unsigned long checkreqprot; 144 145 if (!kstrtoul(str, 0, &checkreqprot)) { 146 if (checkreqprot) 147 pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n"); 148 } 149 return 1; 150 } 151 __setup("checkreqprot=", checkreqprot_setup); 152 153 /** 154 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 155 * 156 * Description: 157 * This function checks the SECMARK reference counter to see if any SECMARK 158 * targets are currently configured, if the reference counter is greater than 159 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 160 * enabled, false (0) if SECMARK is disabled. If the always_check_network 161 * policy capability is enabled, SECMARK is always considered enabled. 162 * 163 */ 164 static int selinux_secmark_enabled(void) 165 { 166 return (selinux_policycap_alwaysnetwork() || 167 atomic_read(&selinux_secmark_refcount)); 168 } 169 170 /** 171 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 172 * 173 * Description: 174 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 175 * (1) if any are enabled or false (0) if neither are enabled. If the 176 * always_check_network policy capability is enabled, peer labeling 177 * is always considered enabled. 178 * 179 */ 180 static int selinux_peerlbl_enabled(void) 181 { 182 return (selinux_policycap_alwaysnetwork() || 183 netlbl_enabled() || selinux_xfrm_enabled()); 184 } 185 186 static int selinux_netcache_avc_callback(u32 event) 187 { 188 if (event == AVC_CALLBACK_RESET) { 189 sel_netif_flush(); 190 sel_netnode_flush(); 191 sel_netport_flush(); 192 synchronize_net(); 193 } 194 return 0; 195 } 196 197 static int selinux_lsm_notifier_avc_callback(u32 event) 198 { 199 if (event == AVC_CALLBACK_RESET) { 200 sel_ib_pkey_flush(); 201 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 202 } 203 204 return 0; 205 } 206 207 /* 208 * initialise the security for the init task 209 */ 210 static void cred_init_security(void) 211 { 212 struct task_security_struct *tsec; 213 214 tsec = selinux_cred(unrcu_pointer(current->real_cred)); 215 tsec->osid = tsec->sid = SECINITSID_KERNEL; 216 } 217 218 /* 219 * get the security ID of a set of credentials 220 */ 221 static inline u32 cred_sid(const struct cred *cred) 222 { 223 const struct task_security_struct *tsec; 224 225 tsec = selinux_cred(cred); 226 return tsec->sid; 227 } 228 229 static void __ad_net_init(struct common_audit_data *ad, 230 struct lsm_network_audit *net, 231 int ifindex, struct sock *sk, u16 family) 232 { 233 ad->type = LSM_AUDIT_DATA_NET; 234 ad->u.net = net; 235 net->netif = ifindex; 236 net->sk = sk; 237 net->family = family; 238 } 239 240 static void ad_net_init_from_sk(struct common_audit_data *ad, 241 struct lsm_network_audit *net, 242 struct sock *sk) 243 { 244 __ad_net_init(ad, net, 0, sk, 0); 245 } 246 247 static void ad_net_init_from_iif(struct common_audit_data *ad, 248 struct lsm_network_audit *net, 249 int ifindex, u16 family) 250 { 251 __ad_net_init(ad, net, ifindex, NULL, family); 252 } 253 254 /* 255 * get the objective security ID of a task 256 */ 257 static inline u32 task_sid_obj(const struct task_struct *task) 258 { 259 u32 sid; 260 261 rcu_read_lock(); 262 sid = cred_sid(__task_cred(task)); 263 rcu_read_unlock(); 264 return sid; 265 } 266 267 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 268 269 /* 270 * Try reloading inode security labels that have been marked as invalid. The 271 * @may_sleep parameter indicates when sleeping and thus reloading labels is 272 * allowed; when set to false, returns -ECHILD when the label is 273 * invalid. The @dentry parameter should be set to a dentry of the inode. 274 */ 275 static int __inode_security_revalidate(struct inode *inode, 276 struct dentry *dentry, 277 bool may_sleep) 278 { 279 struct inode_security_struct *isec = selinux_inode(inode); 280 281 might_sleep_if(may_sleep); 282 283 if (selinux_initialized() && 284 isec->initialized != LABEL_INITIALIZED) { 285 if (!may_sleep) 286 return -ECHILD; 287 288 /* 289 * Try reloading the inode security label. This will fail if 290 * @opt_dentry is NULL and no dentry for this inode can be 291 * found; in that case, continue using the old label. 292 */ 293 inode_doinit_with_dentry(inode, dentry); 294 } 295 return 0; 296 } 297 298 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 299 { 300 return selinux_inode(inode); 301 } 302 303 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 304 { 305 int error; 306 307 error = __inode_security_revalidate(inode, NULL, !rcu); 308 if (error) 309 return ERR_PTR(error); 310 return selinux_inode(inode); 311 } 312 313 /* 314 * Get the security label of an inode. 315 */ 316 static struct inode_security_struct *inode_security(struct inode *inode) 317 { 318 __inode_security_revalidate(inode, NULL, true); 319 return selinux_inode(inode); 320 } 321 322 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 323 { 324 struct inode *inode = d_backing_inode(dentry); 325 326 return selinux_inode(inode); 327 } 328 329 /* 330 * Get the security label of a dentry's backing inode. 331 */ 332 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 333 { 334 struct inode *inode = d_backing_inode(dentry); 335 336 __inode_security_revalidate(inode, dentry, true); 337 return selinux_inode(inode); 338 } 339 340 static void inode_free_security(struct inode *inode) 341 { 342 struct inode_security_struct *isec = selinux_inode(inode); 343 struct superblock_security_struct *sbsec; 344 345 if (!isec) 346 return; 347 sbsec = selinux_superblock(inode->i_sb); 348 /* 349 * As not all inode security structures are in a list, we check for 350 * empty list outside of the lock to make sure that we won't waste 351 * time taking a lock doing nothing. 352 * 353 * The list_del_init() function can be safely called more than once. 354 * It should not be possible for this function to be called with 355 * concurrent list_add(), but for better safety against future changes 356 * in the code, we use list_empty_careful() here. 357 */ 358 if (!list_empty_careful(&isec->list)) { 359 spin_lock(&sbsec->isec_lock); 360 list_del_init(&isec->list); 361 spin_unlock(&sbsec->isec_lock); 362 } 363 } 364 365 struct selinux_mnt_opts { 366 u32 fscontext_sid; 367 u32 context_sid; 368 u32 rootcontext_sid; 369 u32 defcontext_sid; 370 }; 371 372 static void selinux_free_mnt_opts(void *mnt_opts) 373 { 374 kfree(mnt_opts); 375 } 376 377 enum { 378 Opt_error = -1, 379 Opt_context = 0, 380 Opt_defcontext = 1, 381 Opt_fscontext = 2, 382 Opt_rootcontext = 3, 383 Opt_seclabel = 4, 384 }; 385 386 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 387 static const struct { 388 const char *name; 389 int len; 390 int opt; 391 bool has_arg; 392 } tokens[] = { 393 A(context, true), 394 A(fscontext, true), 395 A(defcontext, true), 396 A(rootcontext, true), 397 A(seclabel, false), 398 }; 399 #undef A 400 401 static int match_opt_prefix(char *s, int l, char **arg) 402 { 403 int i; 404 405 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 406 size_t len = tokens[i].len; 407 if (len > l || memcmp(s, tokens[i].name, len)) 408 continue; 409 if (tokens[i].has_arg) { 410 if (len == l || s[len] != '=') 411 continue; 412 *arg = s + len + 1; 413 } else if (len != l) 414 continue; 415 return tokens[i].opt; 416 } 417 return Opt_error; 418 } 419 420 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 421 422 static int may_context_mount_sb_relabel(u32 sid, 423 struct superblock_security_struct *sbsec, 424 const struct cred *cred) 425 { 426 const struct task_security_struct *tsec = selinux_cred(cred); 427 int rc; 428 429 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 430 FILESYSTEM__RELABELFROM, NULL); 431 if (rc) 432 return rc; 433 434 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 435 FILESYSTEM__RELABELTO, NULL); 436 return rc; 437 } 438 439 static int may_context_mount_inode_relabel(u32 sid, 440 struct superblock_security_struct *sbsec, 441 const struct cred *cred) 442 { 443 const struct task_security_struct *tsec = selinux_cred(cred); 444 int rc; 445 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 446 FILESYSTEM__RELABELFROM, NULL); 447 if (rc) 448 return rc; 449 450 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 451 FILESYSTEM__ASSOCIATE, NULL); 452 return rc; 453 } 454 455 static int selinux_is_genfs_special_handling(struct super_block *sb) 456 { 457 /* Special handling. Genfs but also in-core setxattr handler */ 458 return !strcmp(sb->s_type->name, "sysfs") || 459 !strcmp(sb->s_type->name, "pstore") || 460 !strcmp(sb->s_type->name, "debugfs") || 461 !strcmp(sb->s_type->name, "tracefs") || 462 !strcmp(sb->s_type->name, "rootfs") || 463 (selinux_policycap_cgroupseclabel() && 464 (!strcmp(sb->s_type->name, "cgroup") || 465 !strcmp(sb->s_type->name, "cgroup2"))); 466 } 467 468 static int selinux_is_sblabel_mnt(struct super_block *sb) 469 { 470 struct superblock_security_struct *sbsec = selinux_superblock(sb); 471 472 /* 473 * IMPORTANT: Double-check logic in this function when adding a new 474 * SECURITY_FS_USE_* definition! 475 */ 476 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 477 478 switch (sbsec->behavior) { 479 case SECURITY_FS_USE_XATTR: 480 case SECURITY_FS_USE_TRANS: 481 case SECURITY_FS_USE_TASK: 482 case SECURITY_FS_USE_NATIVE: 483 return 1; 484 485 case SECURITY_FS_USE_GENFS: 486 return selinux_is_genfs_special_handling(sb); 487 488 /* Never allow relabeling on context mounts */ 489 case SECURITY_FS_USE_MNTPOINT: 490 case SECURITY_FS_USE_NONE: 491 default: 492 return 0; 493 } 494 } 495 496 static int sb_check_xattr_support(struct super_block *sb) 497 { 498 struct superblock_security_struct *sbsec = selinux_superblock(sb); 499 struct dentry *root = sb->s_root; 500 struct inode *root_inode = d_backing_inode(root); 501 u32 sid; 502 int rc; 503 504 /* 505 * Make sure that the xattr handler exists and that no 506 * error other than -ENODATA is returned by getxattr on 507 * the root directory. -ENODATA is ok, as this may be 508 * the first boot of the SELinux kernel before we have 509 * assigned xattr values to the filesystem. 510 */ 511 if (!(root_inode->i_opflags & IOP_XATTR)) { 512 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", 513 sb->s_id, sb->s_type->name); 514 goto fallback; 515 } 516 517 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 518 if (rc < 0 && rc != -ENODATA) { 519 if (rc == -EOPNOTSUPP) { 520 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", 521 sb->s_id, sb->s_type->name); 522 goto fallback; 523 } else { 524 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", 525 sb->s_id, sb->s_type->name, -rc); 526 return rc; 527 } 528 } 529 return 0; 530 531 fallback: 532 /* No xattr support - try to fallback to genfs if possible. */ 533 rc = security_genfs_sid(sb->s_type->name, "/", 534 SECCLASS_DIR, &sid); 535 if (rc) 536 return -EOPNOTSUPP; 537 538 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", 539 sb->s_id, sb->s_type->name); 540 sbsec->behavior = SECURITY_FS_USE_GENFS; 541 sbsec->sid = sid; 542 return 0; 543 } 544 545 static int sb_finish_set_opts(struct super_block *sb) 546 { 547 struct superblock_security_struct *sbsec = selinux_superblock(sb); 548 struct dentry *root = sb->s_root; 549 struct inode *root_inode = d_backing_inode(root); 550 int rc = 0; 551 552 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 553 rc = sb_check_xattr_support(sb); 554 if (rc) 555 return rc; 556 } 557 558 sbsec->flags |= SE_SBINITIALIZED; 559 560 /* 561 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 562 * leave the flag untouched because sb_clone_mnt_opts might be handing 563 * us a superblock that needs the flag to be cleared. 564 */ 565 if (selinux_is_sblabel_mnt(sb)) 566 sbsec->flags |= SBLABEL_MNT; 567 else 568 sbsec->flags &= ~SBLABEL_MNT; 569 570 /* Initialize the root inode. */ 571 rc = inode_doinit_with_dentry(root_inode, root); 572 573 /* Initialize any other inodes associated with the superblock, e.g. 574 inodes created prior to initial policy load or inodes created 575 during get_sb by a pseudo filesystem that directly 576 populates itself. */ 577 spin_lock(&sbsec->isec_lock); 578 while (!list_empty(&sbsec->isec_head)) { 579 struct inode_security_struct *isec = 580 list_first_entry(&sbsec->isec_head, 581 struct inode_security_struct, list); 582 struct inode *inode = isec->inode; 583 list_del_init(&isec->list); 584 spin_unlock(&sbsec->isec_lock); 585 inode = igrab(inode); 586 if (inode) { 587 if (!IS_PRIVATE(inode)) 588 inode_doinit_with_dentry(inode, NULL); 589 iput(inode); 590 } 591 spin_lock(&sbsec->isec_lock); 592 } 593 spin_unlock(&sbsec->isec_lock); 594 return rc; 595 } 596 597 static int bad_option(struct superblock_security_struct *sbsec, char flag, 598 u32 old_sid, u32 new_sid) 599 { 600 char mnt_flags = sbsec->flags & SE_MNTMASK; 601 602 /* check if the old mount command had the same options */ 603 if (sbsec->flags & SE_SBINITIALIZED) 604 if (!(sbsec->flags & flag) || 605 (old_sid != new_sid)) 606 return 1; 607 608 /* check if we were passed the same options twice, 609 * aka someone passed context=a,context=b 610 */ 611 if (!(sbsec->flags & SE_SBINITIALIZED)) 612 if (mnt_flags & flag) 613 return 1; 614 return 0; 615 } 616 617 /* 618 * Allow filesystems with binary mount data to explicitly set mount point 619 * labeling information. 620 */ 621 static int selinux_set_mnt_opts(struct super_block *sb, 622 void *mnt_opts, 623 unsigned long kern_flags, 624 unsigned long *set_kern_flags) 625 { 626 const struct cred *cred = current_cred(); 627 struct superblock_security_struct *sbsec = selinux_superblock(sb); 628 struct dentry *root = sb->s_root; 629 struct selinux_mnt_opts *opts = mnt_opts; 630 struct inode_security_struct *root_isec; 631 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 632 u32 defcontext_sid = 0; 633 int rc = 0; 634 635 /* 636 * Specifying internal flags without providing a place to 637 * place the results is not allowed 638 */ 639 if (kern_flags && !set_kern_flags) 640 return -EINVAL; 641 642 mutex_lock(&sbsec->lock); 643 644 if (!selinux_initialized()) { 645 if (!opts) { 646 /* Defer initialization until selinux_complete_init, 647 after the initial policy is loaded and the security 648 server is ready to handle calls. */ 649 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 650 sbsec->flags |= SE_SBNATIVE; 651 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 652 } 653 goto out; 654 } 655 rc = -EINVAL; 656 pr_warn("SELinux: Unable to set superblock options " 657 "before the security server is initialized\n"); 658 goto out; 659 } 660 661 /* 662 * Binary mount data FS will come through this function twice. Once 663 * from an explicit call and once from the generic calls from the vfs. 664 * Since the generic VFS calls will not contain any security mount data 665 * we need to skip the double mount verification. 666 * 667 * This does open a hole in which we will not notice if the first 668 * mount using this sb set explicit options and a second mount using 669 * this sb does not set any security options. (The first options 670 * will be used for both mounts) 671 */ 672 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 673 && !opts) 674 goto out; 675 676 root_isec = backing_inode_security_novalidate(root); 677 678 /* 679 * parse the mount options, check if they are valid sids. 680 * also check if someone is trying to mount the same sb more 681 * than once with different security options. 682 */ 683 if (opts) { 684 if (opts->fscontext_sid) { 685 fscontext_sid = opts->fscontext_sid; 686 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 687 fscontext_sid)) 688 goto out_double_mount; 689 sbsec->flags |= FSCONTEXT_MNT; 690 } 691 if (opts->context_sid) { 692 context_sid = opts->context_sid; 693 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 694 context_sid)) 695 goto out_double_mount; 696 sbsec->flags |= CONTEXT_MNT; 697 } 698 if (opts->rootcontext_sid) { 699 rootcontext_sid = opts->rootcontext_sid; 700 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 701 rootcontext_sid)) 702 goto out_double_mount; 703 sbsec->flags |= ROOTCONTEXT_MNT; 704 } 705 if (opts->defcontext_sid) { 706 defcontext_sid = opts->defcontext_sid; 707 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 708 defcontext_sid)) 709 goto out_double_mount; 710 sbsec->flags |= DEFCONTEXT_MNT; 711 } 712 } 713 714 if (sbsec->flags & SE_SBINITIALIZED) { 715 /* previously mounted with options, but not on this attempt? */ 716 if ((sbsec->flags & SE_MNTMASK) && !opts) 717 goto out_double_mount; 718 rc = 0; 719 goto out; 720 } 721 722 if (strcmp(sb->s_type->name, "proc") == 0) 723 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 724 725 if (!strcmp(sb->s_type->name, "debugfs") || 726 !strcmp(sb->s_type->name, "tracefs") || 727 !strcmp(sb->s_type->name, "binder") || 728 !strcmp(sb->s_type->name, "bpf") || 729 !strcmp(sb->s_type->name, "pstore") || 730 !strcmp(sb->s_type->name, "securityfs")) 731 sbsec->flags |= SE_SBGENFS; 732 733 if (!strcmp(sb->s_type->name, "sysfs") || 734 !strcmp(sb->s_type->name, "cgroup") || 735 !strcmp(sb->s_type->name, "cgroup2")) 736 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 737 738 if (!sbsec->behavior) { 739 /* 740 * Determine the labeling behavior to use for this 741 * filesystem type. 742 */ 743 rc = security_fs_use(sb); 744 if (rc) { 745 pr_warn("%s: security_fs_use(%s) returned %d\n", 746 __func__, sb->s_type->name, rc); 747 goto out; 748 } 749 } 750 751 /* 752 * If this is a user namespace mount and the filesystem type is not 753 * explicitly whitelisted, then no contexts are allowed on the command 754 * line and security labels must be ignored. 755 */ 756 if (sb->s_user_ns != &init_user_ns && 757 strcmp(sb->s_type->name, "tmpfs") && 758 strcmp(sb->s_type->name, "ramfs") && 759 strcmp(sb->s_type->name, "devpts") && 760 strcmp(sb->s_type->name, "overlay")) { 761 if (context_sid || fscontext_sid || rootcontext_sid || 762 defcontext_sid) { 763 rc = -EACCES; 764 goto out; 765 } 766 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 767 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 768 rc = security_transition_sid(current_sid(), 769 current_sid(), 770 SECCLASS_FILE, NULL, 771 &sbsec->mntpoint_sid); 772 if (rc) 773 goto out; 774 } 775 goto out_set_opts; 776 } 777 778 /* sets the context of the superblock for the fs being mounted. */ 779 if (fscontext_sid) { 780 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 781 if (rc) 782 goto out; 783 784 sbsec->sid = fscontext_sid; 785 } 786 787 /* 788 * Switch to using mount point labeling behavior. 789 * sets the label used on all file below the mountpoint, and will set 790 * the superblock context if not already set. 791 */ 792 if (sbsec->flags & SE_SBNATIVE) { 793 /* 794 * This means we are initializing a superblock that has been 795 * mounted before the SELinux was initialized and the 796 * filesystem requested native labeling. We had already 797 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags 798 * in the original mount attempt, so now we just need to set 799 * the SECURITY_FS_USE_NATIVE behavior. 800 */ 801 sbsec->behavior = SECURITY_FS_USE_NATIVE; 802 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 803 sbsec->behavior = SECURITY_FS_USE_NATIVE; 804 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 805 } 806 807 if (context_sid) { 808 if (!fscontext_sid) { 809 rc = may_context_mount_sb_relabel(context_sid, sbsec, 810 cred); 811 if (rc) 812 goto out; 813 sbsec->sid = context_sid; 814 } else { 815 rc = may_context_mount_inode_relabel(context_sid, sbsec, 816 cred); 817 if (rc) 818 goto out; 819 } 820 if (!rootcontext_sid) 821 rootcontext_sid = context_sid; 822 823 sbsec->mntpoint_sid = context_sid; 824 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 825 } 826 827 if (rootcontext_sid) { 828 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 829 cred); 830 if (rc) 831 goto out; 832 833 root_isec->sid = rootcontext_sid; 834 root_isec->initialized = LABEL_INITIALIZED; 835 } 836 837 if (defcontext_sid) { 838 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 839 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 840 rc = -EINVAL; 841 pr_warn("SELinux: defcontext option is " 842 "invalid for this filesystem type\n"); 843 goto out; 844 } 845 846 if (defcontext_sid != sbsec->def_sid) { 847 rc = may_context_mount_inode_relabel(defcontext_sid, 848 sbsec, cred); 849 if (rc) 850 goto out; 851 } 852 853 sbsec->def_sid = defcontext_sid; 854 } 855 856 out_set_opts: 857 rc = sb_finish_set_opts(sb); 858 out: 859 mutex_unlock(&sbsec->lock); 860 return rc; 861 out_double_mount: 862 rc = -EINVAL; 863 pr_warn("SELinux: mount invalid. Same superblock, different " 864 "security settings for (dev %s, type %s)\n", sb->s_id, 865 sb->s_type->name); 866 goto out; 867 } 868 869 static int selinux_cmp_sb_context(const struct super_block *oldsb, 870 const struct super_block *newsb) 871 { 872 struct superblock_security_struct *old = selinux_superblock(oldsb); 873 struct superblock_security_struct *new = selinux_superblock(newsb); 874 char oldflags = old->flags & SE_MNTMASK; 875 char newflags = new->flags & SE_MNTMASK; 876 877 if (oldflags != newflags) 878 goto mismatch; 879 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 880 goto mismatch; 881 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 882 goto mismatch; 883 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 884 goto mismatch; 885 if (oldflags & ROOTCONTEXT_MNT) { 886 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 887 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 888 if (oldroot->sid != newroot->sid) 889 goto mismatch; 890 } 891 return 0; 892 mismatch: 893 pr_warn("SELinux: mount invalid. Same superblock, " 894 "different security settings for (dev %s, " 895 "type %s)\n", newsb->s_id, newsb->s_type->name); 896 return -EBUSY; 897 } 898 899 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 900 struct super_block *newsb, 901 unsigned long kern_flags, 902 unsigned long *set_kern_flags) 903 { 904 int rc = 0; 905 const struct superblock_security_struct *oldsbsec = 906 selinux_superblock(oldsb); 907 struct superblock_security_struct *newsbsec = selinux_superblock(newsb); 908 909 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 910 int set_context = (oldsbsec->flags & CONTEXT_MNT); 911 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 912 913 /* 914 * Specifying internal flags without providing a place to 915 * place the results is not allowed. 916 */ 917 if (kern_flags && !set_kern_flags) 918 return -EINVAL; 919 920 mutex_lock(&newsbsec->lock); 921 922 /* 923 * if the parent was able to be mounted it clearly had no special lsm 924 * mount options. thus we can safely deal with this superblock later 925 */ 926 if (!selinux_initialized()) { 927 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 928 newsbsec->flags |= SE_SBNATIVE; 929 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 930 } 931 goto out; 932 } 933 934 /* how can we clone if the old one wasn't set up?? */ 935 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 936 937 /* if fs is reusing a sb, make sure that the contexts match */ 938 if (newsbsec->flags & SE_SBINITIALIZED) { 939 mutex_unlock(&newsbsec->lock); 940 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 941 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 942 return selinux_cmp_sb_context(oldsb, newsb); 943 } 944 945 newsbsec->flags = oldsbsec->flags; 946 947 newsbsec->sid = oldsbsec->sid; 948 newsbsec->def_sid = oldsbsec->def_sid; 949 newsbsec->behavior = oldsbsec->behavior; 950 951 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 952 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 953 rc = security_fs_use(newsb); 954 if (rc) 955 goto out; 956 } 957 958 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 959 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 960 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 961 } 962 963 if (set_context) { 964 u32 sid = oldsbsec->mntpoint_sid; 965 966 if (!set_fscontext) 967 newsbsec->sid = sid; 968 if (!set_rootcontext) { 969 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 970 newisec->sid = sid; 971 } 972 newsbsec->mntpoint_sid = sid; 973 } 974 if (set_rootcontext) { 975 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 976 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 977 978 newisec->sid = oldisec->sid; 979 } 980 981 sb_finish_set_opts(newsb); 982 out: 983 mutex_unlock(&newsbsec->lock); 984 return rc; 985 } 986 987 /* 988 * NOTE: the caller is responsible for freeing the memory even if on error. 989 */ 990 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 991 { 992 struct selinux_mnt_opts *opts = *mnt_opts; 993 u32 *dst_sid; 994 int rc; 995 996 if (token == Opt_seclabel) 997 /* eaten and completely ignored */ 998 return 0; 999 if (!s) 1000 return -EINVAL; 1001 1002 if (!selinux_initialized()) { 1003 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); 1004 return -EINVAL; 1005 } 1006 1007 if (!opts) { 1008 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 1009 if (!opts) 1010 return -ENOMEM; 1011 *mnt_opts = opts; 1012 } 1013 1014 switch (token) { 1015 case Opt_context: 1016 if (opts->context_sid || opts->defcontext_sid) 1017 goto err; 1018 dst_sid = &opts->context_sid; 1019 break; 1020 case Opt_fscontext: 1021 if (opts->fscontext_sid) 1022 goto err; 1023 dst_sid = &opts->fscontext_sid; 1024 break; 1025 case Opt_rootcontext: 1026 if (opts->rootcontext_sid) 1027 goto err; 1028 dst_sid = &opts->rootcontext_sid; 1029 break; 1030 case Opt_defcontext: 1031 if (opts->context_sid || opts->defcontext_sid) 1032 goto err; 1033 dst_sid = &opts->defcontext_sid; 1034 break; 1035 default: 1036 WARN_ON(1); 1037 return -EINVAL; 1038 } 1039 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); 1040 if (rc) 1041 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", 1042 s, rc); 1043 return rc; 1044 1045 err: 1046 pr_warn(SEL_MOUNT_FAIL_MSG); 1047 return -EINVAL; 1048 } 1049 1050 static int show_sid(struct seq_file *m, u32 sid) 1051 { 1052 char *context = NULL; 1053 u32 len; 1054 int rc; 1055 1056 rc = security_sid_to_context(sid, &context, &len); 1057 if (!rc) { 1058 bool has_comma = strchr(context, ','); 1059 1060 seq_putc(m, '='); 1061 if (has_comma) 1062 seq_putc(m, '\"'); 1063 seq_escape(m, context, "\"\n\\"); 1064 if (has_comma) 1065 seq_putc(m, '\"'); 1066 } 1067 kfree(context); 1068 return rc; 1069 } 1070 1071 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1072 { 1073 struct superblock_security_struct *sbsec = selinux_superblock(sb); 1074 int rc; 1075 1076 if (!(sbsec->flags & SE_SBINITIALIZED)) 1077 return 0; 1078 1079 if (!selinux_initialized()) 1080 return 0; 1081 1082 if (sbsec->flags & FSCONTEXT_MNT) { 1083 seq_putc(m, ','); 1084 seq_puts(m, FSCONTEXT_STR); 1085 rc = show_sid(m, sbsec->sid); 1086 if (rc) 1087 return rc; 1088 } 1089 if (sbsec->flags & CONTEXT_MNT) { 1090 seq_putc(m, ','); 1091 seq_puts(m, CONTEXT_STR); 1092 rc = show_sid(m, sbsec->mntpoint_sid); 1093 if (rc) 1094 return rc; 1095 } 1096 if (sbsec->flags & DEFCONTEXT_MNT) { 1097 seq_putc(m, ','); 1098 seq_puts(m, DEFCONTEXT_STR); 1099 rc = show_sid(m, sbsec->def_sid); 1100 if (rc) 1101 return rc; 1102 } 1103 if (sbsec->flags & ROOTCONTEXT_MNT) { 1104 struct dentry *root = sb->s_root; 1105 struct inode_security_struct *isec = backing_inode_security(root); 1106 seq_putc(m, ','); 1107 seq_puts(m, ROOTCONTEXT_STR); 1108 rc = show_sid(m, isec->sid); 1109 if (rc) 1110 return rc; 1111 } 1112 if (sbsec->flags & SBLABEL_MNT) { 1113 seq_putc(m, ','); 1114 seq_puts(m, SECLABEL_STR); 1115 } 1116 return 0; 1117 } 1118 1119 static inline u16 inode_mode_to_security_class(umode_t mode) 1120 { 1121 switch (mode & S_IFMT) { 1122 case S_IFSOCK: 1123 return SECCLASS_SOCK_FILE; 1124 case S_IFLNK: 1125 return SECCLASS_LNK_FILE; 1126 case S_IFREG: 1127 return SECCLASS_FILE; 1128 case S_IFBLK: 1129 return SECCLASS_BLK_FILE; 1130 case S_IFDIR: 1131 return SECCLASS_DIR; 1132 case S_IFCHR: 1133 return SECCLASS_CHR_FILE; 1134 case S_IFIFO: 1135 return SECCLASS_FIFO_FILE; 1136 1137 } 1138 1139 return SECCLASS_FILE; 1140 } 1141 1142 static inline int default_protocol_stream(int protocol) 1143 { 1144 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || 1145 protocol == IPPROTO_MPTCP); 1146 } 1147 1148 static inline int default_protocol_dgram(int protocol) 1149 { 1150 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1151 } 1152 1153 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1154 { 1155 bool extsockclass = selinux_policycap_extsockclass(); 1156 1157 switch (family) { 1158 case PF_UNIX: 1159 switch (type) { 1160 case SOCK_STREAM: 1161 case SOCK_SEQPACKET: 1162 return SECCLASS_UNIX_STREAM_SOCKET; 1163 case SOCK_DGRAM: 1164 case SOCK_RAW: 1165 return SECCLASS_UNIX_DGRAM_SOCKET; 1166 } 1167 break; 1168 case PF_INET: 1169 case PF_INET6: 1170 switch (type) { 1171 case SOCK_STREAM: 1172 case SOCK_SEQPACKET: 1173 if (default_protocol_stream(protocol)) 1174 return SECCLASS_TCP_SOCKET; 1175 else if (extsockclass && protocol == IPPROTO_SCTP) 1176 return SECCLASS_SCTP_SOCKET; 1177 else 1178 return SECCLASS_RAWIP_SOCKET; 1179 case SOCK_DGRAM: 1180 if (default_protocol_dgram(protocol)) 1181 return SECCLASS_UDP_SOCKET; 1182 else if (extsockclass && (protocol == IPPROTO_ICMP || 1183 protocol == IPPROTO_ICMPV6)) 1184 return SECCLASS_ICMP_SOCKET; 1185 else 1186 return SECCLASS_RAWIP_SOCKET; 1187 case SOCK_DCCP: 1188 return SECCLASS_DCCP_SOCKET; 1189 default: 1190 return SECCLASS_RAWIP_SOCKET; 1191 } 1192 break; 1193 case PF_NETLINK: 1194 switch (protocol) { 1195 case NETLINK_ROUTE: 1196 return SECCLASS_NETLINK_ROUTE_SOCKET; 1197 case NETLINK_SOCK_DIAG: 1198 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1199 case NETLINK_NFLOG: 1200 return SECCLASS_NETLINK_NFLOG_SOCKET; 1201 case NETLINK_XFRM: 1202 return SECCLASS_NETLINK_XFRM_SOCKET; 1203 case NETLINK_SELINUX: 1204 return SECCLASS_NETLINK_SELINUX_SOCKET; 1205 case NETLINK_ISCSI: 1206 return SECCLASS_NETLINK_ISCSI_SOCKET; 1207 case NETLINK_AUDIT: 1208 return SECCLASS_NETLINK_AUDIT_SOCKET; 1209 case NETLINK_FIB_LOOKUP: 1210 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1211 case NETLINK_CONNECTOR: 1212 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1213 case NETLINK_NETFILTER: 1214 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1215 case NETLINK_DNRTMSG: 1216 return SECCLASS_NETLINK_DNRT_SOCKET; 1217 case NETLINK_KOBJECT_UEVENT: 1218 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1219 case NETLINK_GENERIC: 1220 return SECCLASS_NETLINK_GENERIC_SOCKET; 1221 case NETLINK_SCSITRANSPORT: 1222 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1223 case NETLINK_RDMA: 1224 return SECCLASS_NETLINK_RDMA_SOCKET; 1225 case NETLINK_CRYPTO: 1226 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1227 default: 1228 return SECCLASS_NETLINK_SOCKET; 1229 } 1230 case PF_PACKET: 1231 return SECCLASS_PACKET_SOCKET; 1232 case PF_KEY: 1233 return SECCLASS_KEY_SOCKET; 1234 case PF_APPLETALK: 1235 return SECCLASS_APPLETALK_SOCKET; 1236 } 1237 1238 if (extsockclass) { 1239 switch (family) { 1240 case PF_AX25: 1241 return SECCLASS_AX25_SOCKET; 1242 case PF_IPX: 1243 return SECCLASS_IPX_SOCKET; 1244 case PF_NETROM: 1245 return SECCLASS_NETROM_SOCKET; 1246 case PF_ATMPVC: 1247 return SECCLASS_ATMPVC_SOCKET; 1248 case PF_X25: 1249 return SECCLASS_X25_SOCKET; 1250 case PF_ROSE: 1251 return SECCLASS_ROSE_SOCKET; 1252 case PF_DECnet: 1253 return SECCLASS_DECNET_SOCKET; 1254 case PF_ATMSVC: 1255 return SECCLASS_ATMSVC_SOCKET; 1256 case PF_RDS: 1257 return SECCLASS_RDS_SOCKET; 1258 case PF_IRDA: 1259 return SECCLASS_IRDA_SOCKET; 1260 case PF_PPPOX: 1261 return SECCLASS_PPPOX_SOCKET; 1262 case PF_LLC: 1263 return SECCLASS_LLC_SOCKET; 1264 case PF_CAN: 1265 return SECCLASS_CAN_SOCKET; 1266 case PF_TIPC: 1267 return SECCLASS_TIPC_SOCKET; 1268 case PF_BLUETOOTH: 1269 return SECCLASS_BLUETOOTH_SOCKET; 1270 case PF_IUCV: 1271 return SECCLASS_IUCV_SOCKET; 1272 case PF_RXRPC: 1273 return SECCLASS_RXRPC_SOCKET; 1274 case PF_ISDN: 1275 return SECCLASS_ISDN_SOCKET; 1276 case PF_PHONET: 1277 return SECCLASS_PHONET_SOCKET; 1278 case PF_IEEE802154: 1279 return SECCLASS_IEEE802154_SOCKET; 1280 case PF_CAIF: 1281 return SECCLASS_CAIF_SOCKET; 1282 case PF_ALG: 1283 return SECCLASS_ALG_SOCKET; 1284 case PF_NFC: 1285 return SECCLASS_NFC_SOCKET; 1286 case PF_VSOCK: 1287 return SECCLASS_VSOCK_SOCKET; 1288 case PF_KCM: 1289 return SECCLASS_KCM_SOCKET; 1290 case PF_QIPCRTR: 1291 return SECCLASS_QIPCRTR_SOCKET; 1292 case PF_SMC: 1293 return SECCLASS_SMC_SOCKET; 1294 case PF_XDP: 1295 return SECCLASS_XDP_SOCKET; 1296 case PF_MCTP: 1297 return SECCLASS_MCTP_SOCKET; 1298 #if PF_MAX > 46 1299 #error New address family defined, please update this function. 1300 #endif 1301 } 1302 } 1303 1304 return SECCLASS_SOCKET; 1305 } 1306 1307 static int selinux_genfs_get_sid(struct dentry *dentry, 1308 u16 tclass, 1309 u16 flags, 1310 u32 *sid) 1311 { 1312 int rc; 1313 struct super_block *sb = dentry->d_sb; 1314 char *buffer, *path; 1315 1316 buffer = (char *)__get_free_page(GFP_KERNEL); 1317 if (!buffer) 1318 return -ENOMEM; 1319 1320 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1321 if (IS_ERR(path)) 1322 rc = PTR_ERR(path); 1323 else { 1324 if (flags & SE_SBPROC) { 1325 /* each process gets a /proc/PID/ entry. Strip off the 1326 * PID part to get a valid selinux labeling. 1327 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1328 while (path[1] >= '0' && path[1] <= '9') { 1329 path[1] = '/'; 1330 path++; 1331 } 1332 } 1333 rc = security_genfs_sid(sb->s_type->name, 1334 path, tclass, sid); 1335 if (rc == -ENOENT) { 1336 /* No match in policy, mark as unlabeled. */ 1337 *sid = SECINITSID_UNLABELED; 1338 rc = 0; 1339 } 1340 } 1341 free_page((unsigned long)buffer); 1342 return rc; 1343 } 1344 1345 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1346 u32 def_sid, u32 *sid) 1347 { 1348 #define INITCONTEXTLEN 255 1349 char *context; 1350 unsigned int len; 1351 int rc; 1352 1353 len = INITCONTEXTLEN; 1354 context = kmalloc(len + 1, GFP_NOFS); 1355 if (!context) 1356 return -ENOMEM; 1357 1358 context[len] = '\0'; 1359 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1360 if (rc == -ERANGE) { 1361 kfree(context); 1362 1363 /* Need a larger buffer. Query for the right size. */ 1364 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1365 if (rc < 0) 1366 return rc; 1367 1368 len = rc; 1369 context = kmalloc(len + 1, GFP_NOFS); 1370 if (!context) 1371 return -ENOMEM; 1372 1373 context[len] = '\0'; 1374 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1375 context, len); 1376 } 1377 if (rc < 0) { 1378 kfree(context); 1379 if (rc != -ENODATA) { 1380 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1381 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1382 return rc; 1383 } 1384 *sid = def_sid; 1385 return 0; 1386 } 1387 1388 rc = security_context_to_sid_default(context, rc, sid, 1389 def_sid, GFP_NOFS); 1390 if (rc) { 1391 char *dev = inode->i_sb->s_id; 1392 unsigned long ino = inode->i_ino; 1393 1394 if (rc == -EINVAL) { 1395 pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s. This indicates you may need to relabel the inode or the filesystem in question.\n", 1396 ino, dev, context); 1397 } else { 1398 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1399 __func__, context, -rc, dev, ino); 1400 } 1401 } 1402 kfree(context); 1403 return 0; 1404 } 1405 1406 /* The inode's security attributes must be initialized before first use. */ 1407 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1408 { 1409 struct superblock_security_struct *sbsec = NULL; 1410 struct inode_security_struct *isec = selinux_inode(inode); 1411 u32 task_sid, sid = 0; 1412 u16 sclass; 1413 struct dentry *dentry; 1414 int rc = 0; 1415 1416 if (isec->initialized == LABEL_INITIALIZED) 1417 return 0; 1418 1419 spin_lock(&isec->lock); 1420 if (isec->initialized == LABEL_INITIALIZED) 1421 goto out_unlock; 1422 1423 if (isec->sclass == SECCLASS_FILE) 1424 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1425 1426 sbsec = selinux_superblock(inode->i_sb); 1427 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1428 /* Defer initialization until selinux_complete_init, 1429 after the initial policy is loaded and the security 1430 server is ready to handle calls. */ 1431 spin_lock(&sbsec->isec_lock); 1432 if (list_empty(&isec->list)) 1433 list_add(&isec->list, &sbsec->isec_head); 1434 spin_unlock(&sbsec->isec_lock); 1435 goto out_unlock; 1436 } 1437 1438 sclass = isec->sclass; 1439 task_sid = isec->task_sid; 1440 sid = isec->sid; 1441 isec->initialized = LABEL_PENDING; 1442 spin_unlock(&isec->lock); 1443 1444 switch (sbsec->behavior) { 1445 /* 1446 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels 1447 * via xattr when called from delayed_superblock_init(). 1448 */ 1449 case SECURITY_FS_USE_NATIVE: 1450 case SECURITY_FS_USE_XATTR: 1451 if (!(inode->i_opflags & IOP_XATTR)) { 1452 sid = sbsec->def_sid; 1453 break; 1454 } 1455 /* Need a dentry, since the xattr API requires one. 1456 Life would be simpler if we could just pass the inode. */ 1457 if (opt_dentry) { 1458 /* Called from d_instantiate or d_splice_alias. */ 1459 dentry = dget(opt_dentry); 1460 } else { 1461 /* 1462 * Called from selinux_complete_init, try to find a dentry. 1463 * Some filesystems really want a connected one, so try 1464 * that first. We could split SECURITY_FS_USE_XATTR in 1465 * two, depending upon that... 1466 */ 1467 dentry = d_find_alias(inode); 1468 if (!dentry) 1469 dentry = d_find_any_alias(inode); 1470 } 1471 if (!dentry) { 1472 /* 1473 * this is can be hit on boot when a file is accessed 1474 * before the policy is loaded. When we load policy we 1475 * may find inodes that have no dentry on the 1476 * sbsec->isec_head list. No reason to complain as these 1477 * will get fixed up the next time we go through 1478 * inode_doinit with a dentry, before these inodes could 1479 * be used again by userspace. 1480 */ 1481 goto out_invalid; 1482 } 1483 1484 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1485 &sid); 1486 dput(dentry); 1487 if (rc) 1488 goto out; 1489 break; 1490 case SECURITY_FS_USE_TASK: 1491 sid = task_sid; 1492 break; 1493 case SECURITY_FS_USE_TRANS: 1494 /* Default to the fs SID. */ 1495 sid = sbsec->sid; 1496 1497 /* Try to obtain a transition SID. */ 1498 rc = security_transition_sid(task_sid, sid, 1499 sclass, NULL, &sid); 1500 if (rc) 1501 goto out; 1502 break; 1503 case SECURITY_FS_USE_MNTPOINT: 1504 sid = sbsec->mntpoint_sid; 1505 break; 1506 default: 1507 /* Default to the fs superblock SID. */ 1508 sid = sbsec->sid; 1509 1510 if ((sbsec->flags & SE_SBGENFS) && 1511 (!S_ISLNK(inode->i_mode) || 1512 selinux_policycap_genfs_seclabel_symlinks())) { 1513 /* We must have a dentry to determine the label on 1514 * procfs inodes */ 1515 if (opt_dentry) { 1516 /* Called from d_instantiate or 1517 * d_splice_alias. */ 1518 dentry = dget(opt_dentry); 1519 } else { 1520 /* Called from selinux_complete_init, try to 1521 * find a dentry. Some filesystems really want 1522 * a connected one, so try that first. 1523 */ 1524 dentry = d_find_alias(inode); 1525 if (!dentry) 1526 dentry = d_find_any_alias(inode); 1527 } 1528 /* 1529 * This can be hit on boot when a file is accessed 1530 * before the policy is loaded. When we load policy we 1531 * may find inodes that have no dentry on the 1532 * sbsec->isec_head list. No reason to complain as 1533 * these will get fixed up the next time we go through 1534 * inode_doinit() with a dentry, before these inodes 1535 * could be used again by userspace. 1536 */ 1537 if (!dentry) 1538 goto out_invalid; 1539 rc = selinux_genfs_get_sid(dentry, sclass, 1540 sbsec->flags, &sid); 1541 if (rc) { 1542 dput(dentry); 1543 goto out; 1544 } 1545 1546 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1547 (inode->i_opflags & IOP_XATTR)) { 1548 rc = inode_doinit_use_xattr(inode, dentry, 1549 sid, &sid); 1550 if (rc) { 1551 dput(dentry); 1552 goto out; 1553 } 1554 } 1555 dput(dentry); 1556 } 1557 break; 1558 } 1559 1560 out: 1561 spin_lock(&isec->lock); 1562 if (isec->initialized == LABEL_PENDING) { 1563 if (rc) { 1564 isec->initialized = LABEL_INVALID; 1565 goto out_unlock; 1566 } 1567 isec->initialized = LABEL_INITIALIZED; 1568 isec->sid = sid; 1569 } 1570 1571 out_unlock: 1572 spin_unlock(&isec->lock); 1573 return rc; 1574 1575 out_invalid: 1576 spin_lock(&isec->lock); 1577 if (isec->initialized == LABEL_PENDING) { 1578 isec->initialized = LABEL_INVALID; 1579 isec->sid = sid; 1580 } 1581 spin_unlock(&isec->lock); 1582 return 0; 1583 } 1584 1585 /* Convert a Linux signal to an access vector. */ 1586 static inline u32 signal_to_av(int sig) 1587 { 1588 u32 perm = 0; 1589 1590 switch (sig) { 1591 case SIGCHLD: 1592 /* Commonly granted from child to parent. */ 1593 perm = PROCESS__SIGCHLD; 1594 break; 1595 case SIGKILL: 1596 /* Cannot be caught or ignored */ 1597 perm = PROCESS__SIGKILL; 1598 break; 1599 case SIGSTOP: 1600 /* Cannot be caught or ignored */ 1601 perm = PROCESS__SIGSTOP; 1602 break; 1603 default: 1604 /* All other signals. */ 1605 perm = PROCESS__SIGNAL; 1606 break; 1607 } 1608 1609 return perm; 1610 } 1611 1612 #if CAP_LAST_CAP > 63 1613 #error Fix SELinux to handle capabilities > 63. 1614 #endif 1615 1616 /* Check whether a task is allowed to use a capability. */ 1617 static int cred_has_capability(const struct cred *cred, 1618 int cap, unsigned int opts, bool initns) 1619 { 1620 struct common_audit_data ad; 1621 struct av_decision avd; 1622 u16 sclass; 1623 u32 sid = cred_sid(cred); 1624 u32 av = CAP_TO_MASK(cap); 1625 int rc; 1626 1627 ad.type = LSM_AUDIT_DATA_CAP; 1628 ad.u.cap = cap; 1629 1630 switch (CAP_TO_INDEX(cap)) { 1631 case 0: 1632 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1633 break; 1634 case 1: 1635 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1636 break; 1637 default: 1638 pr_err("SELinux: out of range capability %d\n", cap); 1639 BUG(); 1640 return -EINVAL; 1641 } 1642 1643 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1644 if (!(opts & CAP_OPT_NOAUDIT)) { 1645 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1646 if (rc2) 1647 return rc2; 1648 } 1649 return rc; 1650 } 1651 1652 /* Check whether a task has a particular permission to an inode. 1653 The 'adp' parameter is optional and allows other audit 1654 data to be passed (e.g. the dentry). */ 1655 static int inode_has_perm(const struct cred *cred, 1656 struct inode *inode, 1657 u32 perms, 1658 struct common_audit_data *adp) 1659 { 1660 struct inode_security_struct *isec; 1661 u32 sid; 1662 1663 if (unlikely(IS_PRIVATE(inode))) 1664 return 0; 1665 1666 sid = cred_sid(cred); 1667 isec = selinux_inode(inode); 1668 1669 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1670 } 1671 1672 /* Same as inode_has_perm, but pass explicit audit data containing 1673 the dentry to help the auditing code to more easily generate the 1674 pathname if needed. */ 1675 static inline int dentry_has_perm(const struct cred *cred, 1676 struct dentry *dentry, 1677 u32 av) 1678 { 1679 struct inode *inode = d_backing_inode(dentry); 1680 struct common_audit_data ad; 1681 1682 ad.type = LSM_AUDIT_DATA_DENTRY; 1683 ad.u.dentry = dentry; 1684 __inode_security_revalidate(inode, dentry, true); 1685 return inode_has_perm(cred, inode, av, &ad); 1686 } 1687 1688 /* Same as inode_has_perm, but pass explicit audit data containing 1689 the path to help the auditing code to more easily generate the 1690 pathname if needed. */ 1691 static inline int path_has_perm(const struct cred *cred, 1692 const struct path *path, 1693 u32 av) 1694 { 1695 struct inode *inode = d_backing_inode(path->dentry); 1696 struct common_audit_data ad; 1697 1698 ad.type = LSM_AUDIT_DATA_PATH; 1699 ad.u.path = *path; 1700 __inode_security_revalidate(inode, path->dentry, true); 1701 return inode_has_perm(cred, inode, av, &ad); 1702 } 1703 1704 /* Same as path_has_perm, but uses the inode from the file struct. */ 1705 static inline int file_path_has_perm(const struct cred *cred, 1706 struct file *file, 1707 u32 av) 1708 { 1709 struct common_audit_data ad; 1710 1711 ad.type = LSM_AUDIT_DATA_FILE; 1712 ad.u.file = file; 1713 return inode_has_perm(cred, file_inode(file), av, &ad); 1714 } 1715 1716 #ifdef CONFIG_BPF_SYSCALL 1717 static int bpf_fd_pass(const struct file *file, u32 sid); 1718 #endif 1719 1720 /* Check whether a task can use an open file descriptor to 1721 access an inode in a given way. Check access to the 1722 descriptor itself, and then use dentry_has_perm to 1723 check a particular permission to the file. 1724 Access to the descriptor is implicitly granted if it 1725 has the same SID as the process. If av is zero, then 1726 access to the file is not checked, e.g. for cases 1727 where only the descriptor is affected like seek. */ 1728 static int file_has_perm(const struct cred *cred, 1729 struct file *file, 1730 u32 av) 1731 { 1732 struct file_security_struct *fsec = selinux_file(file); 1733 struct inode *inode = file_inode(file); 1734 struct common_audit_data ad; 1735 u32 sid = cred_sid(cred); 1736 int rc; 1737 1738 ad.type = LSM_AUDIT_DATA_FILE; 1739 ad.u.file = file; 1740 1741 if (sid != fsec->sid) { 1742 rc = avc_has_perm(sid, fsec->sid, 1743 SECCLASS_FD, 1744 FD__USE, 1745 &ad); 1746 if (rc) 1747 goto out; 1748 } 1749 1750 #ifdef CONFIG_BPF_SYSCALL 1751 rc = bpf_fd_pass(file, cred_sid(cred)); 1752 if (rc) 1753 return rc; 1754 #endif 1755 1756 /* av is zero if only checking access to the descriptor. */ 1757 rc = 0; 1758 if (av) 1759 rc = inode_has_perm(cred, inode, av, &ad); 1760 1761 out: 1762 return rc; 1763 } 1764 1765 /* 1766 * Determine the label for an inode that might be unioned. 1767 */ 1768 static int 1769 selinux_determine_inode_label(const struct task_security_struct *tsec, 1770 struct inode *dir, 1771 const struct qstr *name, u16 tclass, 1772 u32 *_new_isid) 1773 { 1774 const struct superblock_security_struct *sbsec = 1775 selinux_superblock(dir->i_sb); 1776 1777 if ((sbsec->flags & SE_SBINITIALIZED) && 1778 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1779 *_new_isid = sbsec->mntpoint_sid; 1780 } else if ((sbsec->flags & SBLABEL_MNT) && 1781 tsec->create_sid) { 1782 *_new_isid = tsec->create_sid; 1783 } else { 1784 const struct inode_security_struct *dsec = inode_security(dir); 1785 return security_transition_sid(tsec->sid, 1786 dsec->sid, tclass, 1787 name, _new_isid); 1788 } 1789 1790 return 0; 1791 } 1792 1793 /* Check whether a task can create a file. */ 1794 static int may_create(struct inode *dir, 1795 struct dentry *dentry, 1796 u16 tclass) 1797 { 1798 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1799 struct inode_security_struct *dsec; 1800 struct superblock_security_struct *sbsec; 1801 u32 sid, newsid; 1802 struct common_audit_data ad; 1803 int rc; 1804 1805 dsec = inode_security(dir); 1806 sbsec = selinux_superblock(dir->i_sb); 1807 1808 sid = tsec->sid; 1809 1810 ad.type = LSM_AUDIT_DATA_DENTRY; 1811 ad.u.dentry = dentry; 1812 1813 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1814 DIR__ADD_NAME | DIR__SEARCH, 1815 &ad); 1816 if (rc) 1817 return rc; 1818 1819 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1820 &newsid); 1821 if (rc) 1822 return rc; 1823 1824 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1825 if (rc) 1826 return rc; 1827 1828 return avc_has_perm(newsid, sbsec->sid, 1829 SECCLASS_FILESYSTEM, 1830 FILESYSTEM__ASSOCIATE, &ad); 1831 } 1832 1833 #define MAY_LINK 0 1834 #define MAY_UNLINK 1 1835 #define MAY_RMDIR 2 1836 1837 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1838 static int may_link(struct inode *dir, 1839 struct dentry *dentry, 1840 int kind) 1841 1842 { 1843 struct inode_security_struct *dsec, *isec; 1844 struct common_audit_data ad; 1845 u32 sid = current_sid(); 1846 u32 av; 1847 int rc; 1848 1849 dsec = inode_security(dir); 1850 isec = backing_inode_security(dentry); 1851 1852 ad.type = LSM_AUDIT_DATA_DENTRY; 1853 ad.u.dentry = dentry; 1854 1855 av = DIR__SEARCH; 1856 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1857 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1858 if (rc) 1859 return rc; 1860 1861 switch (kind) { 1862 case MAY_LINK: 1863 av = FILE__LINK; 1864 break; 1865 case MAY_UNLINK: 1866 av = FILE__UNLINK; 1867 break; 1868 case MAY_RMDIR: 1869 av = DIR__RMDIR; 1870 break; 1871 default: 1872 pr_warn("SELinux: %s: unrecognized kind %d\n", 1873 __func__, kind); 1874 return 0; 1875 } 1876 1877 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1878 return rc; 1879 } 1880 1881 static inline int may_rename(struct inode *old_dir, 1882 struct dentry *old_dentry, 1883 struct inode *new_dir, 1884 struct dentry *new_dentry) 1885 { 1886 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1887 struct common_audit_data ad; 1888 u32 sid = current_sid(); 1889 u32 av; 1890 int old_is_dir, new_is_dir; 1891 int rc; 1892 1893 old_dsec = inode_security(old_dir); 1894 old_isec = backing_inode_security(old_dentry); 1895 old_is_dir = d_is_dir(old_dentry); 1896 new_dsec = inode_security(new_dir); 1897 1898 ad.type = LSM_AUDIT_DATA_DENTRY; 1899 1900 ad.u.dentry = old_dentry; 1901 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1902 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1903 if (rc) 1904 return rc; 1905 rc = avc_has_perm(sid, old_isec->sid, 1906 old_isec->sclass, FILE__RENAME, &ad); 1907 if (rc) 1908 return rc; 1909 if (old_is_dir && new_dir != old_dir) { 1910 rc = avc_has_perm(sid, old_isec->sid, 1911 old_isec->sclass, DIR__REPARENT, &ad); 1912 if (rc) 1913 return rc; 1914 } 1915 1916 ad.u.dentry = new_dentry; 1917 av = DIR__ADD_NAME | DIR__SEARCH; 1918 if (d_is_positive(new_dentry)) 1919 av |= DIR__REMOVE_NAME; 1920 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1921 if (rc) 1922 return rc; 1923 if (d_is_positive(new_dentry)) { 1924 new_isec = backing_inode_security(new_dentry); 1925 new_is_dir = d_is_dir(new_dentry); 1926 rc = avc_has_perm(sid, new_isec->sid, 1927 new_isec->sclass, 1928 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1929 if (rc) 1930 return rc; 1931 } 1932 1933 return 0; 1934 } 1935 1936 /* Check whether a task can perform a filesystem operation. */ 1937 static int superblock_has_perm(const struct cred *cred, 1938 struct super_block *sb, 1939 u32 perms, 1940 struct common_audit_data *ad) 1941 { 1942 struct superblock_security_struct *sbsec; 1943 u32 sid = cred_sid(cred); 1944 1945 sbsec = selinux_superblock(sb); 1946 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1947 } 1948 1949 /* Convert a Linux mode and permission mask to an access vector. */ 1950 static inline u32 file_mask_to_av(int mode, int mask) 1951 { 1952 u32 av = 0; 1953 1954 if (!S_ISDIR(mode)) { 1955 if (mask & MAY_EXEC) 1956 av |= FILE__EXECUTE; 1957 if (mask & MAY_READ) 1958 av |= FILE__READ; 1959 1960 if (mask & MAY_APPEND) 1961 av |= FILE__APPEND; 1962 else if (mask & MAY_WRITE) 1963 av |= FILE__WRITE; 1964 1965 } else { 1966 if (mask & MAY_EXEC) 1967 av |= DIR__SEARCH; 1968 if (mask & MAY_WRITE) 1969 av |= DIR__WRITE; 1970 if (mask & MAY_READ) 1971 av |= DIR__READ; 1972 } 1973 1974 return av; 1975 } 1976 1977 /* Convert a Linux file to an access vector. */ 1978 static inline u32 file_to_av(const struct file *file) 1979 { 1980 u32 av = 0; 1981 1982 if (file->f_mode & FMODE_READ) 1983 av |= FILE__READ; 1984 if (file->f_mode & FMODE_WRITE) { 1985 if (file->f_flags & O_APPEND) 1986 av |= FILE__APPEND; 1987 else 1988 av |= FILE__WRITE; 1989 } 1990 if (!av) { 1991 /* 1992 * Special file opened with flags 3 for ioctl-only use. 1993 */ 1994 av = FILE__IOCTL; 1995 } 1996 1997 return av; 1998 } 1999 2000 /* 2001 * Convert a file to an access vector and include the correct 2002 * open permission. 2003 */ 2004 static inline u32 open_file_to_av(struct file *file) 2005 { 2006 u32 av = file_to_av(file); 2007 struct inode *inode = file_inode(file); 2008 2009 if (selinux_policycap_openperm() && 2010 inode->i_sb->s_magic != SOCKFS_MAGIC) 2011 av |= FILE__OPEN; 2012 2013 return av; 2014 } 2015 2016 /* Hook functions begin here. */ 2017 2018 static int selinux_binder_set_context_mgr(const struct cred *mgr) 2019 { 2020 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, 2021 BINDER__SET_CONTEXT_MGR, NULL); 2022 } 2023 2024 static int selinux_binder_transaction(const struct cred *from, 2025 const struct cred *to) 2026 { 2027 u32 mysid = current_sid(); 2028 u32 fromsid = cred_sid(from); 2029 u32 tosid = cred_sid(to); 2030 int rc; 2031 2032 if (mysid != fromsid) { 2033 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2034 BINDER__IMPERSONATE, NULL); 2035 if (rc) 2036 return rc; 2037 } 2038 2039 return avc_has_perm(fromsid, tosid, 2040 SECCLASS_BINDER, BINDER__CALL, NULL); 2041 } 2042 2043 static int selinux_binder_transfer_binder(const struct cred *from, 2044 const struct cred *to) 2045 { 2046 return avc_has_perm(cred_sid(from), cred_sid(to), 2047 SECCLASS_BINDER, BINDER__TRANSFER, 2048 NULL); 2049 } 2050 2051 static int selinux_binder_transfer_file(const struct cred *from, 2052 const struct cred *to, 2053 const struct file *file) 2054 { 2055 u32 sid = cred_sid(to); 2056 struct file_security_struct *fsec = selinux_file(file); 2057 struct dentry *dentry = file->f_path.dentry; 2058 struct inode_security_struct *isec; 2059 struct common_audit_data ad; 2060 int rc; 2061 2062 ad.type = LSM_AUDIT_DATA_PATH; 2063 ad.u.path = file->f_path; 2064 2065 if (sid != fsec->sid) { 2066 rc = avc_has_perm(sid, fsec->sid, 2067 SECCLASS_FD, 2068 FD__USE, 2069 &ad); 2070 if (rc) 2071 return rc; 2072 } 2073 2074 #ifdef CONFIG_BPF_SYSCALL 2075 rc = bpf_fd_pass(file, sid); 2076 if (rc) 2077 return rc; 2078 #endif 2079 2080 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2081 return 0; 2082 2083 isec = backing_inode_security(dentry); 2084 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2085 &ad); 2086 } 2087 2088 static int selinux_ptrace_access_check(struct task_struct *child, 2089 unsigned int mode) 2090 { 2091 u32 sid = current_sid(); 2092 u32 csid = task_sid_obj(child); 2093 2094 if (mode & PTRACE_MODE_READ) 2095 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, 2096 NULL); 2097 2098 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, 2099 NULL); 2100 } 2101 2102 static int selinux_ptrace_traceme(struct task_struct *parent) 2103 { 2104 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), 2105 SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2106 } 2107 2108 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, 2109 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2110 { 2111 return avc_has_perm(current_sid(), task_sid_obj(target), 2112 SECCLASS_PROCESS, PROCESS__GETCAP, NULL); 2113 } 2114 2115 static int selinux_capset(struct cred *new, const struct cred *old, 2116 const kernel_cap_t *effective, 2117 const kernel_cap_t *inheritable, 2118 const kernel_cap_t *permitted) 2119 { 2120 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2121 PROCESS__SETCAP, NULL); 2122 } 2123 2124 /* 2125 * (This comment used to live with the selinux_task_setuid hook, 2126 * which was removed). 2127 * 2128 * Since setuid only affects the current process, and since the SELinux 2129 * controls are not based on the Linux identity attributes, SELinux does not 2130 * need to control this operation. However, SELinux does control the use of 2131 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2132 */ 2133 2134 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2135 int cap, unsigned int opts) 2136 { 2137 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2138 } 2139 2140 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2141 { 2142 const struct cred *cred = current_cred(); 2143 int rc = 0; 2144 2145 if (!sb) 2146 return 0; 2147 2148 switch (cmds) { 2149 case Q_SYNC: 2150 case Q_QUOTAON: 2151 case Q_QUOTAOFF: 2152 case Q_SETINFO: 2153 case Q_SETQUOTA: 2154 case Q_XQUOTAOFF: 2155 case Q_XQUOTAON: 2156 case Q_XSETQLIM: 2157 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2158 break; 2159 case Q_GETFMT: 2160 case Q_GETINFO: 2161 case Q_GETQUOTA: 2162 case Q_XGETQUOTA: 2163 case Q_XGETQSTAT: 2164 case Q_XGETQSTATV: 2165 case Q_XGETNEXTQUOTA: 2166 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2167 break; 2168 default: 2169 rc = 0; /* let the kernel handle invalid cmds */ 2170 break; 2171 } 2172 return rc; 2173 } 2174 2175 static int selinux_quota_on(struct dentry *dentry) 2176 { 2177 const struct cred *cred = current_cred(); 2178 2179 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2180 } 2181 2182 static int selinux_syslog(int type) 2183 { 2184 switch (type) { 2185 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2186 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2187 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2188 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2189 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2190 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2191 /* Set level of messages printed to console */ 2192 case SYSLOG_ACTION_CONSOLE_LEVEL: 2193 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2194 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2195 NULL); 2196 } 2197 /* All other syslog types */ 2198 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2199 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2200 } 2201 2202 /* 2203 * Check that a process has enough memory to allocate a new virtual 2204 * mapping. 0 means there is enough memory for the allocation to 2205 * succeed and -ENOMEM implies there is not. 2206 * 2207 * Do not audit the selinux permission check, as this is applied to all 2208 * processes that allocate mappings. 2209 */ 2210 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2211 { 2212 int rc, cap_sys_admin = 0; 2213 2214 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2215 CAP_OPT_NOAUDIT, true); 2216 if (rc == 0) 2217 cap_sys_admin = 1; 2218 2219 return cap_sys_admin; 2220 } 2221 2222 /* binprm security operations */ 2223 2224 static u32 ptrace_parent_sid(void) 2225 { 2226 u32 sid = 0; 2227 struct task_struct *tracer; 2228 2229 rcu_read_lock(); 2230 tracer = ptrace_parent(current); 2231 if (tracer) 2232 sid = task_sid_obj(tracer); 2233 rcu_read_unlock(); 2234 2235 return sid; 2236 } 2237 2238 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2239 const struct task_security_struct *old_tsec, 2240 const struct task_security_struct *new_tsec) 2241 { 2242 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2243 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2244 int rc; 2245 u32 av; 2246 2247 if (!nnp && !nosuid) 2248 return 0; /* neither NNP nor nosuid */ 2249 2250 if (new_tsec->sid == old_tsec->sid) 2251 return 0; /* No change in credentials */ 2252 2253 /* 2254 * If the policy enables the nnp_nosuid_transition policy capability, 2255 * then we permit transitions under NNP or nosuid if the 2256 * policy allows the corresponding permission between 2257 * the old and new contexts. 2258 */ 2259 if (selinux_policycap_nnp_nosuid_transition()) { 2260 av = 0; 2261 if (nnp) 2262 av |= PROCESS2__NNP_TRANSITION; 2263 if (nosuid) 2264 av |= PROCESS2__NOSUID_TRANSITION; 2265 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2266 SECCLASS_PROCESS2, av, NULL); 2267 if (!rc) 2268 return 0; 2269 } 2270 2271 /* 2272 * We also permit NNP or nosuid transitions to bounded SIDs, 2273 * i.e. SIDs that are guaranteed to only be allowed a subset 2274 * of the permissions of the current SID. 2275 */ 2276 rc = security_bounded_transition(old_tsec->sid, 2277 new_tsec->sid); 2278 if (!rc) 2279 return 0; 2280 2281 /* 2282 * On failure, preserve the errno values for NNP vs nosuid. 2283 * NNP: Operation not permitted for caller. 2284 * nosuid: Permission denied to file. 2285 */ 2286 if (nnp) 2287 return -EPERM; 2288 return -EACCES; 2289 } 2290 2291 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2292 { 2293 const struct task_security_struct *old_tsec; 2294 struct task_security_struct *new_tsec; 2295 struct inode_security_struct *isec; 2296 struct common_audit_data ad; 2297 struct inode *inode = file_inode(bprm->file); 2298 int rc; 2299 2300 /* SELinux context only depends on initial program or script and not 2301 * the script interpreter */ 2302 2303 old_tsec = selinux_cred(current_cred()); 2304 new_tsec = selinux_cred(bprm->cred); 2305 isec = inode_security(inode); 2306 2307 /* Default to the current task SID. */ 2308 new_tsec->sid = old_tsec->sid; 2309 new_tsec->osid = old_tsec->sid; 2310 2311 /* Reset fs, key, and sock SIDs on execve. */ 2312 new_tsec->create_sid = 0; 2313 new_tsec->keycreate_sid = 0; 2314 new_tsec->sockcreate_sid = 0; 2315 2316 if (old_tsec->exec_sid) { 2317 new_tsec->sid = old_tsec->exec_sid; 2318 /* Reset exec SID on execve. */ 2319 new_tsec->exec_sid = 0; 2320 2321 /* Fail on NNP or nosuid if not an allowed transition. */ 2322 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2323 if (rc) 2324 return rc; 2325 } else { 2326 /* Check for a default transition on this program. */ 2327 rc = security_transition_sid(old_tsec->sid, 2328 isec->sid, SECCLASS_PROCESS, NULL, 2329 &new_tsec->sid); 2330 if (rc) 2331 return rc; 2332 2333 /* 2334 * Fallback to old SID on NNP or nosuid if not an allowed 2335 * transition. 2336 */ 2337 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2338 if (rc) 2339 new_tsec->sid = old_tsec->sid; 2340 } 2341 2342 ad.type = LSM_AUDIT_DATA_FILE; 2343 ad.u.file = bprm->file; 2344 2345 if (new_tsec->sid == old_tsec->sid) { 2346 rc = avc_has_perm(old_tsec->sid, isec->sid, 2347 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2348 if (rc) 2349 return rc; 2350 } else { 2351 /* Check permissions for the transition. */ 2352 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2353 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2354 if (rc) 2355 return rc; 2356 2357 rc = avc_has_perm(new_tsec->sid, isec->sid, 2358 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2359 if (rc) 2360 return rc; 2361 2362 /* Check for shared state */ 2363 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2364 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2365 SECCLASS_PROCESS, PROCESS__SHARE, 2366 NULL); 2367 if (rc) 2368 return -EPERM; 2369 } 2370 2371 /* Make sure that anyone attempting to ptrace over a task that 2372 * changes its SID has the appropriate permit */ 2373 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2374 u32 ptsid = ptrace_parent_sid(); 2375 if (ptsid != 0) { 2376 rc = avc_has_perm(ptsid, new_tsec->sid, 2377 SECCLASS_PROCESS, 2378 PROCESS__PTRACE, NULL); 2379 if (rc) 2380 return -EPERM; 2381 } 2382 } 2383 2384 /* Clear any possibly unsafe personality bits on exec: */ 2385 bprm->per_clear |= PER_CLEAR_ON_SETID; 2386 2387 /* Enable secure mode for SIDs transitions unless 2388 the noatsecure permission is granted between 2389 the two SIDs, i.e. ahp returns 0. */ 2390 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2391 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2392 NULL); 2393 bprm->secureexec |= !!rc; 2394 } 2395 2396 return 0; 2397 } 2398 2399 static int match_file(const void *p, struct file *file, unsigned fd) 2400 { 2401 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2402 } 2403 2404 /* Derived from fs/exec.c:flush_old_files. */ 2405 static inline void flush_unauthorized_files(const struct cred *cred, 2406 struct files_struct *files) 2407 { 2408 struct file *file, *devnull = NULL; 2409 struct tty_struct *tty; 2410 int drop_tty = 0; 2411 unsigned n; 2412 2413 tty = get_current_tty(); 2414 if (tty) { 2415 spin_lock(&tty->files_lock); 2416 if (!list_empty(&tty->tty_files)) { 2417 struct tty_file_private *file_priv; 2418 2419 /* Revalidate access to controlling tty. 2420 Use file_path_has_perm on the tty path directly 2421 rather than using file_has_perm, as this particular 2422 open file may belong to another process and we are 2423 only interested in the inode-based check here. */ 2424 file_priv = list_first_entry(&tty->tty_files, 2425 struct tty_file_private, list); 2426 file = file_priv->file; 2427 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2428 drop_tty = 1; 2429 } 2430 spin_unlock(&tty->files_lock); 2431 tty_kref_put(tty); 2432 } 2433 /* Reset controlling tty. */ 2434 if (drop_tty) 2435 no_tty(); 2436 2437 /* Revalidate access to inherited open files. */ 2438 n = iterate_fd(files, 0, match_file, cred); 2439 if (!n) /* none found? */ 2440 return; 2441 2442 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2443 if (IS_ERR(devnull)) 2444 devnull = NULL; 2445 /* replace all the matching ones with this */ 2446 do { 2447 replace_fd(n - 1, devnull, 0); 2448 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2449 if (devnull) 2450 fput(devnull); 2451 } 2452 2453 /* 2454 * Prepare a process for imminent new credential changes due to exec 2455 */ 2456 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2457 { 2458 struct task_security_struct *new_tsec; 2459 struct rlimit *rlim, *initrlim; 2460 int rc, i; 2461 2462 new_tsec = selinux_cred(bprm->cred); 2463 if (new_tsec->sid == new_tsec->osid) 2464 return; 2465 2466 /* Close files for which the new task SID is not authorized. */ 2467 flush_unauthorized_files(bprm->cred, current->files); 2468 2469 /* Always clear parent death signal on SID transitions. */ 2470 current->pdeath_signal = 0; 2471 2472 /* Check whether the new SID can inherit resource limits from the old 2473 * SID. If not, reset all soft limits to the lower of the current 2474 * task's hard limit and the init task's soft limit. 2475 * 2476 * Note that the setting of hard limits (even to lower them) can be 2477 * controlled by the setrlimit check. The inclusion of the init task's 2478 * soft limit into the computation is to avoid resetting soft limits 2479 * higher than the default soft limit for cases where the default is 2480 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2481 */ 2482 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2483 PROCESS__RLIMITINH, NULL); 2484 if (rc) { 2485 /* protect against do_prlimit() */ 2486 task_lock(current); 2487 for (i = 0; i < RLIM_NLIMITS; i++) { 2488 rlim = current->signal->rlim + i; 2489 initrlim = init_task.signal->rlim + i; 2490 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2491 } 2492 task_unlock(current); 2493 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2494 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2495 } 2496 } 2497 2498 /* 2499 * Clean up the process immediately after the installation of new credentials 2500 * due to exec 2501 */ 2502 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2503 { 2504 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2505 u32 osid, sid; 2506 int rc; 2507 2508 osid = tsec->osid; 2509 sid = tsec->sid; 2510 2511 if (sid == osid) 2512 return; 2513 2514 /* Check whether the new SID can inherit signal state from the old SID. 2515 * If not, clear itimers to avoid subsequent signal generation and 2516 * flush and unblock signals. 2517 * 2518 * This must occur _after_ the task SID has been updated so that any 2519 * kill done after the flush will be checked against the new SID. 2520 */ 2521 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2522 if (rc) { 2523 clear_itimer(); 2524 2525 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); 2526 if (!fatal_signal_pending(current)) { 2527 flush_sigqueue(¤t->pending); 2528 flush_sigqueue(¤t->signal->shared_pending); 2529 flush_signal_handlers(current, 1); 2530 sigemptyset(¤t->blocked); 2531 recalc_sigpending(); 2532 } 2533 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); 2534 } 2535 2536 /* Wake up the parent if it is waiting so that it can recheck 2537 * wait permission to the new task SID. */ 2538 read_lock(&tasklist_lock); 2539 __wake_up_parent(current, unrcu_pointer(current->real_parent)); 2540 read_unlock(&tasklist_lock); 2541 } 2542 2543 /* superblock security operations */ 2544 2545 static int selinux_sb_alloc_security(struct super_block *sb) 2546 { 2547 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2548 2549 mutex_init(&sbsec->lock); 2550 INIT_LIST_HEAD(&sbsec->isec_head); 2551 spin_lock_init(&sbsec->isec_lock); 2552 sbsec->sid = SECINITSID_UNLABELED; 2553 sbsec->def_sid = SECINITSID_FILE; 2554 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2555 2556 return 0; 2557 } 2558 2559 static inline int opt_len(const char *s) 2560 { 2561 bool open_quote = false; 2562 int len; 2563 char c; 2564 2565 for (len = 0; (c = s[len]) != '\0'; len++) { 2566 if (c == '"') 2567 open_quote = !open_quote; 2568 if (c == ',' && !open_quote) 2569 break; 2570 } 2571 return len; 2572 } 2573 2574 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2575 { 2576 char *from = options; 2577 char *to = options; 2578 bool first = true; 2579 int rc; 2580 2581 while (1) { 2582 int len = opt_len(from); 2583 int token; 2584 char *arg = NULL; 2585 2586 token = match_opt_prefix(from, len, &arg); 2587 2588 if (token != Opt_error) { 2589 char *p, *q; 2590 2591 /* strip quotes */ 2592 if (arg) { 2593 for (p = q = arg; p < from + len; p++) { 2594 char c = *p; 2595 if (c != '"') 2596 *q++ = c; 2597 } 2598 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2599 if (!arg) { 2600 rc = -ENOMEM; 2601 goto free_opt; 2602 } 2603 } 2604 rc = selinux_add_opt(token, arg, mnt_opts); 2605 kfree(arg); 2606 arg = NULL; 2607 if (unlikely(rc)) { 2608 goto free_opt; 2609 } 2610 } else { 2611 if (!first) { // copy with preceding comma 2612 from--; 2613 len++; 2614 } 2615 if (to != from) 2616 memmove(to, from, len); 2617 to += len; 2618 first = false; 2619 } 2620 if (!from[len]) 2621 break; 2622 from += len + 1; 2623 } 2624 *to = '\0'; 2625 return 0; 2626 2627 free_opt: 2628 if (*mnt_opts) { 2629 selinux_free_mnt_opts(*mnt_opts); 2630 *mnt_opts = NULL; 2631 } 2632 return rc; 2633 } 2634 2635 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2636 { 2637 struct selinux_mnt_opts *opts = mnt_opts; 2638 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2639 2640 /* 2641 * Superblock not initialized (i.e. no options) - reject if any 2642 * options specified, otherwise accept. 2643 */ 2644 if (!(sbsec->flags & SE_SBINITIALIZED)) 2645 return opts ? 1 : 0; 2646 2647 /* 2648 * Superblock initialized and no options specified - reject if 2649 * superblock has any options set, otherwise accept. 2650 */ 2651 if (!opts) 2652 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2653 2654 if (opts->fscontext_sid) { 2655 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2656 opts->fscontext_sid)) 2657 return 1; 2658 } 2659 if (opts->context_sid) { 2660 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2661 opts->context_sid)) 2662 return 1; 2663 } 2664 if (opts->rootcontext_sid) { 2665 struct inode_security_struct *root_isec; 2666 2667 root_isec = backing_inode_security(sb->s_root); 2668 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2669 opts->rootcontext_sid)) 2670 return 1; 2671 } 2672 if (opts->defcontext_sid) { 2673 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2674 opts->defcontext_sid)) 2675 return 1; 2676 } 2677 return 0; 2678 } 2679 2680 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2681 { 2682 struct selinux_mnt_opts *opts = mnt_opts; 2683 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2684 2685 if (!(sbsec->flags & SE_SBINITIALIZED)) 2686 return 0; 2687 2688 if (!opts) 2689 return 0; 2690 2691 if (opts->fscontext_sid) { 2692 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2693 opts->fscontext_sid)) 2694 goto out_bad_option; 2695 } 2696 if (opts->context_sid) { 2697 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2698 opts->context_sid)) 2699 goto out_bad_option; 2700 } 2701 if (opts->rootcontext_sid) { 2702 struct inode_security_struct *root_isec; 2703 root_isec = backing_inode_security(sb->s_root); 2704 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2705 opts->rootcontext_sid)) 2706 goto out_bad_option; 2707 } 2708 if (opts->defcontext_sid) { 2709 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2710 opts->defcontext_sid)) 2711 goto out_bad_option; 2712 } 2713 return 0; 2714 2715 out_bad_option: 2716 pr_warn("SELinux: unable to change security options " 2717 "during remount (dev %s, type=%s)\n", sb->s_id, 2718 sb->s_type->name); 2719 return -EINVAL; 2720 } 2721 2722 static int selinux_sb_kern_mount(struct super_block *sb) 2723 { 2724 const struct cred *cred = current_cred(); 2725 struct common_audit_data ad; 2726 2727 ad.type = LSM_AUDIT_DATA_DENTRY; 2728 ad.u.dentry = sb->s_root; 2729 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2730 } 2731 2732 static int selinux_sb_statfs(struct dentry *dentry) 2733 { 2734 const struct cred *cred = current_cred(); 2735 struct common_audit_data ad; 2736 2737 ad.type = LSM_AUDIT_DATA_DENTRY; 2738 ad.u.dentry = dentry->d_sb->s_root; 2739 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2740 } 2741 2742 static int selinux_mount(const char *dev_name, 2743 const struct path *path, 2744 const char *type, 2745 unsigned long flags, 2746 void *data) 2747 { 2748 const struct cred *cred = current_cred(); 2749 2750 if (flags & MS_REMOUNT) 2751 return superblock_has_perm(cred, path->dentry->d_sb, 2752 FILESYSTEM__REMOUNT, NULL); 2753 else 2754 return path_has_perm(cred, path, FILE__MOUNTON); 2755 } 2756 2757 static int selinux_move_mount(const struct path *from_path, 2758 const struct path *to_path) 2759 { 2760 const struct cred *cred = current_cred(); 2761 2762 return path_has_perm(cred, to_path, FILE__MOUNTON); 2763 } 2764 2765 static int selinux_umount(struct vfsmount *mnt, int flags) 2766 { 2767 const struct cred *cred = current_cred(); 2768 2769 return superblock_has_perm(cred, mnt->mnt_sb, 2770 FILESYSTEM__UNMOUNT, NULL); 2771 } 2772 2773 static int selinux_fs_context_submount(struct fs_context *fc, 2774 struct super_block *reference) 2775 { 2776 const struct superblock_security_struct *sbsec = selinux_superblock(reference); 2777 struct selinux_mnt_opts *opts; 2778 2779 /* 2780 * Ensure that fc->security remains NULL when no options are set 2781 * as expected by selinux_set_mnt_opts(). 2782 */ 2783 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) 2784 return 0; 2785 2786 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 2787 if (!opts) 2788 return -ENOMEM; 2789 2790 if (sbsec->flags & FSCONTEXT_MNT) 2791 opts->fscontext_sid = sbsec->sid; 2792 if (sbsec->flags & CONTEXT_MNT) 2793 opts->context_sid = sbsec->mntpoint_sid; 2794 if (sbsec->flags & DEFCONTEXT_MNT) 2795 opts->defcontext_sid = sbsec->def_sid; 2796 fc->security = opts; 2797 return 0; 2798 } 2799 2800 static int selinux_fs_context_dup(struct fs_context *fc, 2801 struct fs_context *src_fc) 2802 { 2803 const struct selinux_mnt_opts *src = src_fc->security; 2804 2805 if (!src) 2806 return 0; 2807 2808 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); 2809 return fc->security ? 0 : -ENOMEM; 2810 } 2811 2812 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2813 fsparam_string(CONTEXT_STR, Opt_context), 2814 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2815 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2816 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2817 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2818 {} 2819 }; 2820 2821 static int selinux_fs_context_parse_param(struct fs_context *fc, 2822 struct fs_parameter *param) 2823 { 2824 struct fs_parse_result result; 2825 int opt; 2826 2827 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2828 if (opt < 0) 2829 return opt; 2830 2831 return selinux_add_opt(opt, param->string, &fc->security); 2832 } 2833 2834 /* inode security operations */ 2835 2836 static int selinux_inode_alloc_security(struct inode *inode) 2837 { 2838 struct inode_security_struct *isec = selinux_inode(inode); 2839 u32 sid = current_sid(); 2840 2841 spin_lock_init(&isec->lock); 2842 INIT_LIST_HEAD(&isec->list); 2843 isec->inode = inode; 2844 isec->sid = SECINITSID_UNLABELED; 2845 isec->sclass = SECCLASS_FILE; 2846 isec->task_sid = sid; 2847 isec->initialized = LABEL_INVALID; 2848 2849 return 0; 2850 } 2851 2852 static void selinux_inode_free_security(struct inode *inode) 2853 { 2854 inode_free_security(inode); 2855 } 2856 2857 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2858 const struct qstr *name, 2859 const char **xattr_name, void **ctx, 2860 u32 *ctxlen) 2861 { 2862 u32 newsid; 2863 int rc; 2864 2865 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2866 d_inode(dentry->d_parent), name, 2867 inode_mode_to_security_class(mode), 2868 &newsid); 2869 if (rc) 2870 return rc; 2871 2872 if (xattr_name) 2873 *xattr_name = XATTR_NAME_SELINUX; 2874 2875 return security_sid_to_context(newsid, (char **)ctx, 2876 ctxlen); 2877 } 2878 2879 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2880 struct qstr *name, 2881 const struct cred *old, 2882 struct cred *new) 2883 { 2884 u32 newsid; 2885 int rc; 2886 struct task_security_struct *tsec; 2887 2888 rc = selinux_determine_inode_label(selinux_cred(old), 2889 d_inode(dentry->d_parent), name, 2890 inode_mode_to_security_class(mode), 2891 &newsid); 2892 if (rc) 2893 return rc; 2894 2895 tsec = selinux_cred(new); 2896 tsec->create_sid = newsid; 2897 return 0; 2898 } 2899 2900 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2901 const struct qstr *qstr, 2902 struct xattr *xattrs, int *xattr_count) 2903 { 2904 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2905 struct superblock_security_struct *sbsec; 2906 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); 2907 u32 newsid, clen; 2908 int rc; 2909 char *context; 2910 2911 sbsec = selinux_superblock(dir->i_sb); 2912 2913 newsid = tsec->create_sid; 2914 2915 rc = selinux_determine_inode_label(tsec, dir, qstr, 2916 inode_mode_to_security_class(inode->i_mode), 2917 &newsid); 2918 if (rc) 2919 return rc; 2920 2921 /* Possibly defer initialization to selinux_complete_init. */ 2922 if (sbsec->flags & SE_SBINITIALIZED) { 2923 struct inode_security_struct *isec = selinux_inode(inode); 2924 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2925 isec->sid = newsid; 2926 isec->initialized = LABEL_INITIALIZED; 2927 } 2928 2929 if (!selinux_initialized() || 2930 !(sbsec->flags & SBLABEL_MNT)) 2931 return -EOPNOTSUPP; 2932 2933 if (xattr) { 2934 rc = security_sid_to_context_force(newsid, 2935 &context, &clen); 2936 if (rc) 2937 return rc; 2938 xattr->value = context; 2939 xattr->value_len = clen; 2940 xattr->name = XATTR_SELINUX_SUFFIX; 2941 } 2942 2943 return 0; 2944 } 2945 2946 static int selinux_inode_init_security_anon(struct inode *inode, 2947 const struct qstr *name, 2948 const struct inode *context_inode) 2949 { 2950 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2951 struct common_audit_data ad; 2952 struct inode_security_struct *isec; 2953 int rc; 2954 2955 if (unlikely(!selinux_initialized())) 2956 return 0; 2957 2958 isec = selinux_inode(inode); 2959 2960 /* 2961 * We only get here once per ephemeral inode. The inode has 2962 * been initialized via inode_alloc_security but is otherwise 2963 * untouched. 2964 */ 2965 2966 if (context_inode) { 2967 struct inode_security_struct *context_isec = 2968 selinux_inode(context_inode); 2969 if (context_isec->initialized != LABEL_INITIALIZED) { 2970 pr_err("SELinux: context_inode is not initialized\n"); 2971 return -EACCES; 2972 } 2973 2974 isec->sclass = context_isec->sclass; 2975 isec->sid = context_isec->sid; 2976 } else { 2977 isec->sclass = SECCLASS_ANON_INODE; 2978 rc = security_transition_sid( 2979 tsec->sid, tsec->sid, 2980 isec->sclass, name, &isec->sid); 2981 if (rc) 2982 return rc; 2983 } 2984 2985 isec->initialized = LABEL_INITIALIZED; 2986 /* 2987 * Now that we've initialized security, check whether we're 2988 * allowed to actually create this type of anonymous inode. 2989 */ 2990 2991 ad.type = LSM_AUDIT_DATA_ANONINODE; 2992 ad.u.anonclass = name ? (const char *)name->name : "?"; 2993 2994 return avc_has_perm(tsec->sid, 2995 isec->sid, 2996 isec->sclass, 2997 FILE__CREATE, 2998 &ad); 2999 } 3000 3001 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3002 { 3003 return may_create(dir, dentry, SECCLASS_FILE); 3004 } 3005 3006 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3007 { 3008 return may_link(dir, old_dentry, MAY_LINK); 3009 } 3010 3011 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3012 { 3013 return may_link(dir, dentry, MAY_UNLINK); 3014 } 3015 3016 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3017 { 3018 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3019 } 3020 3021 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3022 { 3023 return may_create(dir, dentry, SECCLASS_DIR); 3024 } 3025 3026 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3027 { 3028 return may_link(dir, dentry, MAY_RMDIR); 3029 } 3030 3031 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3032 { 3033 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3034 } 3035 3036 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3037 struct inode *new_inode, struct dentry *new_dentry) 3038 { 3039 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3040 } 3041 3042 static int selinux_inode_readlink(struct dentry *dentry) 3043 { 3044 const struct cred *cred = current_cred(); 3045 3046 return dentry_has_perm(cred, dentry, FILE__READ); 3047 } 3048 3049 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3050 bool rcu) 3051 { 3052 const struct cred *cred = current_cred(); 3053 struct common_audit_data ad; 3054 struct inode_security_struct *isec; 3055 u32 sid; 3056 3057 ad.type = LSM_AUDIT_DATA_DENTRY; 3058 ad.u.dentry = dentry; 3059 sid = cred_sid(cred); 3060 isec = inode_security_rcu(inode, rcu); 3061 if (IS_ERR(isec)) 3062 return PTR_ERR(isec); 3063 3064 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); 3065 } 3066 3067 static noinline int audit_inode_permission(struct inode *inode, 3068 u32 perms, u32 audited, u32 denied, 3069 int result) 3070 { 3071 struct common_audit_data ad; 3072 struct inode_security_struct *isec = selinux_inode(inode); 3073 3074 ad.type = LSM_AUDIT_DATA_INODE; 3075 ad.u.inode = inode; 3076 3077 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3078 audited, denied, result, &ad); 3079 } 3080 3081 static int selinux_inode_permission(struct inode *inode, int mask) 3082 { 3083 const struct cred *cred = current_cred(); 3084 u32 perms; 3085 bool from_access; 3086 bool no_block = mask & MAY_NOT_BLOCK; 3087 struct inode_security_struct *isec; 3088 u32 sid; 3089 struct av_decision avd; 3090 int rc, rc2; 3091 u32 audited, denied; 3092 3093 from_access = mask & MAY_ACCESS; 3094 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3095 3096 /* No permission to check. Existence test. */ 3097 if (!mask) 3098 return 0; 3099 3100 if (unlikely(IS_PRIVATE(inode))) 3101 return 0; 3102 3103 perms = file_mask_to_av(inode->i_mode, mask); 3104 3105 sid = cred_sid(cred); 3106 isec = inode_security_rcu(inode, no_block); 3107 if (IS_ERR(isec)) 3108 return PTR_ERR(isec); 3109 3110 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, 3111 &avd); 3112 audited = avc_audit_required(perms, &avd, rc, 3113 from_access ? FILE__AUDIT_ACCESS : 0, 3114 &denied); 3115 if (likely(!audited)) 3116 return rc; 3117 3118 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3119 if (rc2) 3120 return rc2; 3121 return rc; 3122 } 3123 3124 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3125 { 3126 const struct cred *cred = current_cred(); 3127 struct inode *inode = d_backing_inode(dentry); 3128 unsigned int ia_valid = iattr->ia_valid; 3129 __u32 av = FILE__WRITE; 3130 3131 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3132 if (ia_valid & ATTR_FORCE) { 3133 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3134 ATTR_FORCE); 3135 if (!ia_valid) 3136 return 0; 3137 } 3138 3139 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3140 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3141 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3142 3143 if (selinux_policycap_openperm() && 3144 inode->i_sb->s_magic != SOCKFS_MAGIC && 3145 (ia_valid & ATTR_SIZE) && 3146 !(ia_valid & ATTR_FILE)) 3147 av |= FILE__OPEN; 3148 3149 return dentry_has_perm(cred, dentry, av); 3150 } 3151 3152 static int selinux_inode_getattr(const struct path *path) 3153 { 3154 return path_has_perm(current_cred(), path, FILE__GETATTR); 3155 } 3156 3157 static bool has_cap_mac_admin(bool audit) 3158 { 3159 const struct cred *cred = current_cred(); 3160 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3161 3162 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3163 return false; 3164 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3165 return false; 3166 return true; 3167 } 3168 3169 static int selinux_inode_setxattr(struct mnt_idmap *idmap, 3170 struct dentry *dentry, const char *name, 3171 const void *value, size_t size, int flags) 3172 { 3173 struct inode *inode = d_backing_inode(dentry); 3174 struct inode_security_struct *isec; 3175 struct superblock_security_struct *sbsec; 3176 struct common_audit_data ad; 3177 u32 newsid, sid = current_sid(); 3178 int rc = 0; 3179 3180 if (strcmp(name, XATTR_NAME_SELINUX)) { 3181 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3182 if (rc) 3183 return rc; 3184 3185 /* Not an attribute we recognize, so just check the 3186 ordinary setattr permission. */ 3187 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3188 } 3189 3190 if (!selinux_initialized()) 3191 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); 3192 3193 sbsec = selinux_superblock(inode->i_sb); 3194 if (!(sbsec->flags & SBLABEL_MNT)) 3195 return -EOPNOTSUPP; 3196 3197 if (!inode_owner_or_capable(idmap, inode)) 3198 return -EPERM; 3199 3200 ad.type = LSM_AUDIT_DATA_DENTRY; 3201 ad.u.dentry = dentry; 3202 3203 isec = backing_inode_security(dentry); 3204 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3205 FILE__RELABELFROM, &ad); 3206 if (rc) 3207 return rc; 3208 3209 rc = security_context_to_sid(value, size, &newsid, 3210 GFP_KERNEL); 3211 if (rc == -EINVAL) { 3212 if (!has_cap_mac_admin(true)) { 3213 struct audit_buffer *ab; 3214 size_t audit_size; 3215 3216 /* We strip a nul only if it is at the end, otherwise the 3217 * context contains a nul and we should audit that */ 3218 if (value) { 3219 const char *str = value; 3220 3221 if (str[size - 1] == '\0') 3222 audit_size = size - 1; 3223 else 3224 audit_size = size; 3225 } else { 3226 audit_size = 0; 3227 } 3228 ab = audit_log_start(audit_context(), 3229 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3230 if (!ab) 3231 return rc; 3232 audit_log_format(ab, "op=setxattr invalid_context="); 3233 audit_log_n_untrustedstring(ab, value, audit_size); 3234 audit_log_end(ab); 3235 3236 return rc; 3237 } 3238 rc = security_context_to_sid_force(value, 3239 size, &newsid); 3240 } 3241 if (rc) 3242 return rc; 3243 3244 rc = avc_has_perm(sid, newsid, isec->sclass, 3245 FILE__RELABELTO, &ad); 3246 if (rc) 3247 return rc; 3248 3249 rc = security_validate_transition(isec->sid, newsid, 3250 sid, isec->sclass); 3251 if (rc) 3252 return rc; 3253 3254 return avc_has_perm(newsid, 3255 sbsec->sid, 3256 SECCLASS_FILESYSTEM, 3257 FILESYSTEM__ASSOCIATE, 3258 &ad); 3259 } 3260 3261 static int selinux_inode_set_acl(struct mnt_idmap *idmap, 3262 struct dentry *dentry, const char *acl_name, 3263 struct posix_acl *kacl) 3264 { 3265 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3266 } 3267 3268 static int selinux_inode_get_acl(struct mnt_idmap *idmap, 3269 struct dentry *dentry, const char *acl_name) 3270 { 3271 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); 3272 } 3273 3274 static int selinux_inode_remove_acl(struct mnt_idmap *idmap, 3275 struct dentry *dentry, const char *acl_name) 3276 { 3277 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3278 } 3279 3280 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3281 const void *value, size_t size, 3282 int flags) 3283 { 3284 struct inode *inode = d_backing_inode(dentry); 3285 struct inode_security_struct *isec; 3286 u32 newsid; 3287 int rc; 3288 3289 if (strcmp(name, XATTR_NAME_SELINUX)) { 3290 /* Not an attribute we recognize, so nothing to do. */ 3291 return; 3292 } 3293 3294 if (!selinux_initialized()) { 3295 /* If we haven't even been initialized, then we can't validate 3296 * against a policy, so leave the label as invalid. It may 3297 * resolve to a valid label on the next revalidation try if 3298 * we've since initialized. 3299 */ 3300 return; 3301 } 3302 3303 rc = security_context_to_sid_force(value, size, 3304 &newsid); 3305 if (rc) { 3306 pr_err("SELinux: unable to map context to SID" 3307 "for (%s, %lu), rc=%d\n", 3308 inode->i_sb->s_id, inode->i_ino, -rc); 3309 return; 3310 } 3311 3312 isec = backing_inode_security(dentry); 3313 spin_lock(&isec->lock); 3314 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3315 isec->sid = newsid; 3316 isec->initialized = LABEL_INITIALIZED; 3317 spin_unlock(&isec->lock); 3318 } 3319 3320 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3321 { 3322 const struct cred *cred = current_cred(); 3323 3324 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3325 } 3326 3327 static int selinux_inode_listxattr(struct dentry *dentry) 3328 { 3329 const struct cred *cred = current_cred(); 3330 3331 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3332 } 3333 3334 static int selinux_inode_removexattr(struct mnt_idmap *idmap, 3335 struct dentry *dentry, const char *name) 3336 { 3337 if (strcmp(name, XATTR_NAME_SELINUX)) { 3338 int rc = cap_inode_removexattr(idmap, dentry, name); 3339 if (rc) 3340 return rc; 3341 3342 /* Not an attribute we recognize, so just check the 3343 ordinary setattr permission. */ 3344 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3345 } 3346 3347 if (!selinux_initialized()) 3348 return 0; 3349 3350 /* No one is allowed to remove a SELinux security label. 3351 You can change the label, but all data must be labeled. */ 3352 return -EACCES; 3353 } 3354 3355 static int selinux_path_notify(const struct path *path, u64 mask, 3356 unsigned int obj_type) 3357 { 3358 int ret; 3359 u32 perm; 3360 3361 struct common_audit_data ad; 3362 3363 ad.type = LSM_AUDIT_DATA_PATH; 3364 ad.u.path = *path; 3365 3366 /* 3367 * Set permission needed based on the type of mark being set. 3368 * Performs an additional check for sb watches. 3369 */ 3370 switch (obj_type) { 3371 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3372 perm = FILE__WATCH_MOUNT; 3373 break; 3374 case FSNOTIFY_OBJ_TYPE_SB: 3375 perm = FILE__WATCH_SB; 3376 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3377 FILESYSTEM__WATCH, &ad); 3378 if (ret) 3379 return ret; 3380 break; 3381 case FSNOTIFY_OBJ_TYPE_INODE: 3382 perm = FILE__WATCH; 3383 break; 3384 default: 3385 return -EINVAL; 3386 } 3387 3388 /* blocking watches require the file:watch_with_perm permission */ 3389 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3390 perm |= FILE__WATCH_WITH_PERM; 3391 3392 /* watches on read-like events need the file:watch_reads permission */ 3393 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3394 perm |= FILE__WATCH_READS; 3395 3396 return path_has_perm(current_cred(), path, perm); 3397 } 3398 3399 /* 3400 * Copy the inode security context value to the user. 3401 * 3402 * Permission check is handled by selinux_inode_getxattr hook. 3403 */ 3404 static int selinux_inode_getsecurity(struct mnt_idmap *idmap, 3405 struct inode *inode, const char *name, 3406 void **buffer, bool alloc) 3407 { 3408 u32 size; 3409 int error; 3410 char *context = NULL; 3411 struct inode_security_struct *isec; 3412 3413 /* 3414 * If we're not initialized yet, then we can't validate contexts, so 3415 * just let vfs_getxattr fall back to using the on-disk xattr. 3416 */ 3417 if (!selinux_initialized() || 3418 strcmp(name, XATTR_SELINUX_SUFFIX)) 3419 return -EOPNOTSUPP; 3420 3421 /* 3422 * If the caller has CAP_MAC_ADMIN, then get the raw context 3423 * value even if it is not defined by current policy; otherwise, 3424 * use the in-core value under current policy. 3425 * Use the non-auditing forms of the permission checks since 3426 * getxattr may be called by unprivileged processes commonly 3427 * and lack of permission just means that we fall back to the 3428 * in-core context value, not a denial. 3429 */ 3430 isec = inode_security(inode); 3431 if (has_cap_mac_admin(false)) 3432 error = security_sid_to_context_force(isec->sid, &context, 3433 &size); 3434 else 3435 error = security_sid_to_context(isec->sid, 3436 &context, &size); 3437 if (error) 3438 return error; 3439 error = size; 3440 if (alloc) { 3441 *buffer = context; 3442 goto out_nofree; 3443 } 3444 kfree(context); 3445 out_nofree: 3446 return error; 3447 } 3448 3449 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3450 const void *value, size_t size, int flags) 3451 { 3452 struct inode_security_struct *isec = inode_security_novalidate(inode); 3453 struct superblock_security_struct *sbsec; 3454 u32 newsid; 3455 int rc; 3456 3457 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3458 return -EOPNOTSUPP; 3459 3460 sbsec = selinux_superblock(inode->i_sb); 3461 if (!(sbsec->flags & SBLABEL_MNT)) 3462 return -EOPNOTSUPP; 3463 3464 if (!value || !size) 3465 return -EACCES; 3466 3467 rc = security_context_to_sid(value, size, &newsid, 3468 GFP_KERNEL); 3469 if (rc) 3470 return rc; 3471 3472 spin_lock(&isec->lock); 3473 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3474 isec->sid = newsid; 3475 isec->initialized = LABEL_INITIALIZED; 3476 spin_unlock(&isec->lock); 3477 return 0; 3478 } 3479 3480 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3481 { 3482 const int len = sizeof(XATTR_NAME_SELINUX); 3483 3484 if (!selinux_initialized()) 3485 return 0; 3486 3487 if (buffer && len <= buffer_size) 3488 memcpy(buffer, XATTR_NAME_SELINUX, len); 3489 return len; 3490 } 3491 3492 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3493 { 3494 struct inode_security_struct *isec = inode_security_novalidate(inode); 3495 *secid = isec->sid; 3496 } 3497 3498 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3499 { 3500 u32 sid; 3501 struct task_security_struct *tsec; 3502 struct cred *new_creds = *new; 3503 3504 if (new_creds == NULL) { 3505 new_creds = prepare_creds(); 3506 if (!new_creds) 3507 return -ENOMEM; 3508 } 3509 3510 tsec = selinux_cred(new_creds); 3511 /* Get label from overlay inode and set it in create_sid */ 3512 selinux_inode_getsecid(d_inode(src), &sid); 3513 tsec->create_sid = sid; 3514 *new = new_creds; 3515 return 0; 3516 } 3517 3518 static int selinux_inode_copy_up_xattr(const char *name) 3519 { 3520 /* The copy_up hook above sets the initial context on an inode, but we 3521 * don't then want to overwrite it by blindly copying all the lower 3522 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3523 */ 3524 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3525 return 1; /* Discard */ 3526 /* 3527 * Any other attribute apart from SELINUX is not claimed, supported 3528 * by selinux. 3529 */ 3530 return -EOPNOTSUPP; 3531 } 3532 3533 /* kernfs node operations */ 3534 3535 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3536 struct kernfs_node *kn) 3537 { 3538 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3539 u32 parent_sid, newsid, clen; 3540 int rc; 3541 char *context; 3542 3543 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3544 if (rc == -ENODATA) 3545 return 0; 3546 else if (rc < 0) 3547 return rc; 3548 3549 clen = (u32)rc; 3550 context = kmalloc(clen, GFP_KERNEL); 3551 if (!context) 3552 return -ENOMEM; 3553 3554 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3555 if (rc < 0) { 3556 kfree(context); 3557 return rc; 3558 } 3559 3560 rc = security_context_to_sid(context, clen, &parent_sid, 3561 GFP_KERNEL); 3562 kfree(context); 3563 if (rc) 3564 return rc; 3565 3566 if (tsec->create_sid) { 3567 newsid = tsec->create_sid; 3568 } else { 3569 u16 secclass = inode_mode_to_security_class(kn->mode); 3570 struct qstr q; 3571 3572 q.name = kn->name; 3573 q.hash_len = hashlen_string(kn_dir, kn->name); 3574 3575 rc = security_transition_sid(tsec->sid, 3576 parent_sid, secclass, &q, 3577 &newsid); 3578 if (rc) 3579 return rc; 3580 } 3581 3582 rc = security_sid_to_context_force(newsid, 3583 &context, &clen); 3584 if (rc) 3585 return rc; 3586 3587 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3588 XATTR_CREATE); 3589 kfree(context); 3590 return rc; 3591 } 3592 3593 3594 /* file security operations */ 3595 3596 static int selinux_revalidate_file_permission(struct file *file, int mask) 3597 { 3598 const struct cred *cred = current_cred(); 3599 struct inode *inode = file_inode(file); 3600 3601 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3602 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3603 mask |= MAY_APPEND; 3604 3605 return file_has_perm(cred, file, 3606 file_mask_to_av(inode->i_mode, mask)); 3607 } 3608 3609 static int selinux_file_permission(struct file *file, int mask) 3610 { 3611 struct inode *inode = file_inode(file); 3612 struct file_security_struct *fsec = selinux_file(file); 3613 struct inode_security_struct *isec; 3614 u32 sid = current_sid(); 3615 3616 if (!mask) 3617 /* No permission to check. Existence test. */ 3618 return 0; 3619 3620 isec = inode_security(inode); 3621 if (sid == fsec->sid && fsec->isid == isec->sid && 3622 fsec->pseqno == avc_policy_seqno()) 3623 /* No change since file_open check. */ 3624 return 0; 3625 3626 return selinux_revalidate_file_permission(file, mask); 3627 } 3628 3629 static int selinux_file_alloc_security(struct file *file) 3630 { 3631 struct file_security_struct *fsec = selinux_file(file); 3632 u32 sid = current_sid(); 3633 3634 fsec->sid = sid; 3635 fsec->fown_sid = sid; 3636 3637 return 0; 3638 } 3639 3640 /* 3641 * Check whether a task has the ioctl permission and cmd 3642 * operation to an inode. 3643 */ 3644 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3645 u32 requested, u16 cmd) 3646 { 3647 struct common_audit_data ad; 3648 struct file_security_struct *fsec = selinux_file(file); 3649 struct inode *inode = file_inode(file); 3650 struct inode_security_struct *isec; 3651 struct lsm_ioctlop_audit ioctl; 3652 u32 ssid = cred_sid(cred); 3653 int rc; 3654 u8 driver = cmd >> 8; 3655 u8 xperm = cmd & 0xff; 3656 3657 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3658 ad.u.op = &ioctl; 3659 ad.u.op->cmd = cmd; 3660 ad.u.op->path = file->f_path; 3661 3662 if (ssid != fsec->sid) { 3663 rc = avc_has_perm(ssid, fsec->sid, 3664 SECCLASS_FD, 3665 FD__USE, 3666 &ad); 3667 if (rc) 3668 goto out; 3669 } 3670 3671 if (unlikely(IS_PRIVATE(inode))) 3672 return 0; 3673 3674 isec = inode_security(inode); 3675 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3676 requested, driver, xperm, &ad); 3677 out: 3678 return rc; 3679 } 3680 3681 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3682 unsigned long arg) 3683 { 3684 const struct cred *cred = current_cred(); 3685 int error = 0; 3686 3687 switch (cmd) { 3688 case FIONREAD: 3689 case FIBMAP: 3690 case FIGETBSZ: 3691 case FS_IOC_GETFLAGS: 3692 case FS_IOC_GETVERSION: 3693 error = file_has_perm(cred, file, FILE__GETATTR); 3694 break; 3695 3696 case FS_IOC_SETFLAGS: 3697 case FS_IOC_SETVERSION: 3698 error = file_has_perm(cred, file, FILE__SETATTR); 3699 break; 3700 3701 /* sys_ioctl() checks */ 3702 case FIONBIO: 3703 case FIOASYNC: 3704 error = file_has_perm(cred, file, 0); 3705 break; 3706 3707 case KDSKBENT: 3708 case KDSKBSENT: 3709 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3710 CAP_OPT_NONE, true); 3711 break; 3712 3713 case FIOCLEX: 3714 case FIONCLEX: 3715 if (!selinux_policycap_ioctl_skip_cloexec()) 3716 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3717 break; 3718 3719 /* default case assumes that the command will go 3720 * to the file's ioctl() function. 3721 */ 3722 default: 3723 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3724 } 3725 return error; 3726 } 3727 3728 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd, 3729 unsigned long arg) 3730 { 3731 /* 3732 * If we are in a 64-bit kernel running 32-bit userspace, we need to 3733 * make sure we don't compare 32-bit flags to 64-bit flags. 3734 */ 3735 switch (cmd) { 3736 case FS_IOC32_GETFLAGS: 3737 cmd = FS_IOC_GETFLAGS; 3738 break; 3739 case FS_IOC32_SETFLAGS: 3740 cmd = FS_IOC_SETFLAGS; 3741 break; 3742 case FS_IOC32_GETVERSION: 3743 cmd = FS_IOC_GETVERSION; 3744 break; 3745 case FS_IOC32_SETVERSION: 3746 cmd = FS_IOC_SETVERSION; 3747 break; 3748 default: 3749 break; 3750 } 3751 3752 return selinux_file_ioctl(file, cmd, arg); 3753 } 3754 3755 static int default_noexec __ro_after_init; 3756 3757 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3758 { 3759 const struct cred *cred = current_cred(); 3760 u32 sid = cred_sid(cred); 3761 int rc = 0; 3762 3763 if (default_noexec && 3764 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3765 (!shared && (prot & PROT_WRITE)))) { 3766 /* 3767 * We are making executable an anonymous mapping or a 3768 * private file mapping that will also be writable. 3769 * This has an additional check. 3770 */ 3771 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3772 PROCESS__EXECMEM, NULL); 3773 if (rc) 3774 goto error; 3775 } 3776 3777 if (file) { 3778 /* read access is always possible with a mapping */ 3779 u32 av = FILE__READ; 3780 3781 /* write access only matters if the mapping is shared */ 3782 if (shared && (prot & PROT_WRITE)) 3783 av |= FILE__WRITE; 3784 3785 if (prot & PROT_EXEC) 3786 av |= FILE__EXECUTE; 3787 3788 return file_has_perm(cred, file, av); 3789 } 3790 3791 error: 3792 return rc; 3793 } 3794 3795 static int selinux_mmap_addr(unsigned long addr) 3796 { 3797 int rc = 0; 3798 3799 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3800 u32 sid = current_sid(); 3801 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3802 MEMPROTECT__MMAP_ZERO, NULL); 3803 } 3804 3805 return rc; 3806 } 3807 3808 static int selinux_mmap_file(struct file *file, 3809 unsigned long reqprot __always_unused, 3810 unsigned long prot, unsigned long flags) 3811 { 3812 struct common_audit_data ad; 3813 int rc; 3814 3815 if (file) { 3816 ad.type = LSM_AUDIT_DATA_FILE; 3817 ad.u.file = file; 3818 rc = inode_has_perm(current_cred(), file_inode(file), 3819 FILE__MAP, &ad); 3820 if (rc) 3821 return rc; 3822 } 3823 3824 return file_map_prot_check(file, prot, 3825 (flags & MAP_TYPE) == MAP_SHARED); 3826 } 3827 3828 static int selinux_file_mprotect(struct vm_area_struct *vma, 3829 unsigned long reqprot __always_unused, 3830 unsigned long prot) 3831 { 3832 const struct cred *cred = current_cred(); 3833 u32 sid = cred_sid(cred); 3834 3835 if (default_noexec && 3836 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3837 int rc = 0; 3838 if (vma_is_initial_heap(vma)) { 3839 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3840 PROCESS__EXECHEAP, NULL); 3841 } else if (!vma->vm_file && (vma_is_initial_stack(vma) || 3842 vma_is_stack_for_current(vma))) { 3843 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3844 PROCESS__EXECSTACK, NULL); 3845 } else if (vma->vm_file && vma->anon_vma) { 3846 /* 3847 * We are making executable a file mapping that has 3848 * had some COW done. Since pages might have been 3849 * written, check ability to execute the possibly 3850 * modified content. This typically should only 3851 * occur for text relocations. 3852 */ 3853 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3854 } 3855 if (rc) 3856 return rc; 3857 } 3858 3859 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3860 } 3861 3862 static int selinux_file_lock(struct file *file, unsigned int cmd) 3863 { 3864 const struct cred *cred = current_cred(); 3865 3866 return file_has_perm(cred, file, FILE__LOCK); 3867 } 3868 3869 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3870 unsigned long arg) 3871 { 3872 const struct cred *cred = current_cred(); 3873 int err = 0; 3874 3875 switch (cmd) { 3876 case F_SETFL: 3877 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3878 err = file_has_perm(cred, file, FILE__WRITE); 3879 break; 3880 } 3881 fallthrough; 3882 case F_SETOWN: 3883 case F_SETSIG: 3884 case F_GETFL: 3885 case F_GETOWN: 3886 case F_GETSIG: 3887 case F_GETOWNER_UIDS: 3888 /* Just check FD__USE permission */ 3889 err = file_has_perm(cred, file, 0); 3890 break; 3891 case F_GETLK: 3892 case F_SETLK: 3893 case F_SETLKW: 3894 case F_OFD_GETLK: 3895 case F_OFD_SETLK: 3896 case F_OFD_SETLKW: 3897 #if BITS_PER_LONG == 32 3898 case F_GETLK64: 3899 case F_SETLK64: 3900 case F_SETLKW64: 3901 #endif 3902 err = file_has_perm(cred, file, FILE__LOCK); 3903 break; 3904 } 3905 3906 return err; 3907 } 3908 3909 static void selinux_file_set_fowner(struct file *file) 3910 { 3911 struct file_security_struct *fsec; 3912 3913 fsec = selinux_file(file); 3914 fsec->fown_sid = current_sid(); 3915 } 3916 3917 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3918 struct fown_struct *fown, int signum) 3919 { 3920 struct file *file; 3921 u32 sid = task_sid_obj(tsk); 3922 u32 perm; 3923 struct file_security_struct *fsec; 3924 3925 /* struct fown_struct is never outside the context of a struct file */ 3926 file = container_of(fown, struct file, f_owner); 3927 3928 fsec = selinux_file(file); 3929 3930 if (!signum) 3931 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3932 else 3933 perm = signal_to_av(signum); 3934 3935 return avc_has_perm(fsec->fown_sid, sid, 3936 SECCLASS_PROCESS, perm, NULL); 3937 } 3938 3939 static int selinux_file_receive(struct file *file) 3940 { 3941 const struct cred *cred = current_cred(); 3942 3943 return file_has_perm(cred, file, file_to_av(file)); 3944 } 3945 3946 static int selinux_file_open(struct file *file) 3947 { 3948 struct file_security_struct *fsec; 3949 struct inode_security_struct *isec; 3950 3951 fsec = selinux_file(file); 3952 isec = inode_security(file_inode(file)); 3953 /* 3954 * Save inode label and policy sequence number 3955 * at open-time so that selinux_file_permission 3956 * can determine whether revalidation is necessary. 3957 * Task label is already saved in the file security 3958 * struct as its SID. 3959 */ 3960 fsec->isid = isec->sid; 3961 fsec->pseqno = avc_policy_seqno(); 3962 /* 3963 * Since the inode label or policy seqno may have changed 3964 * between the selinux_inode_permission check and the saving 3965 * of state above, recheck that access is still permitted. 3966 * Otherwise, access might never be revalidated against the 3967 * new inode label or new policy. 3968 * This check is not redundant - do not remove. 3969 */ 3970 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3971 } 3972 3973 /* task security operations */ 3974 3975 static int selinux_task_alloc(struct task_struct *task, 3976 unsigned long clone_flags) 3977 { 3978 u32 sid = current_sid(); 3979 3980 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3981 } 3982 3983 /* 3984 * prepare a new set of credentials for modification 3985 */ 3986 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3987 gfp_t gfp) 3988 { 3989 const struct task_security_struct *old_tsec = selinux_cred(old); 3990 struct task_security_struct *tsec = selinux_cred(new); 3991 3992 *tsec = *old_tsec; 3993 return 0; 3994 } 3995 3996 /* 3997 * transfer the SELinux data to a blank set of creds 3998 */ 3999 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 4000 { 4001 const struct task_security_struct *old_tsec = selinux_cred(old); 4002 struct task_security_struct *tsec = selinux_cred(new); 4003 4004 *tsec = *old_tsec; 4005 } 4006 4007 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 4008 { 4009 *secid = cred_sid(c); 4010 } 4011 4012 /* 4013 * set the security data for a kernel service 4014 * - all the creation contexts are set to unlabelled 4015 */ 4016 static int selinux_kernel_act_as(struct cred *new, u32 secid) 4017 { 4018 struct task_security_struct *tsec = selinux_cred(new); 4019 u32 sid = current_sid(); 4020 int ret; 4021 4022 ret = avc_has_perm(sid, secid, 4023 SECCLASS_KERNEL_SERVICE, 4024 KERNEL_SERVICE__USE_AS_OVERRIDE, 4025 NULL); 4026 if (ret == 0) { 4027 tsec->sid = secid; 4028 tsec->create_sid = 0; 4029 tsec->keycreate_sid = 0; 4030 tsec->sockcreate_sid = 0; 4031 } 4032 return ret; 4033 } 4034 4035 /* 4036 * set the file creation context in a security record to the same as the 4037 * objective context of the specified inode 4038 */ 4039 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4040 { 4041 struct inode_security_struct *isec = inode_security(inode); 4042 struct task_security_struct *tsec = selinux_cred(new); 4043 u32 sid = current_sid(); 4044 int ret; 4045 4046 ret = avc_has_perm(sid, isec->sid, 4047 SECCLASS_KERNEL_SERVICE, 4048 KERNEL_SERVICE__CREATE_FILES_AS, 4049 NULL); 4050 4051 if (ret == 0) 4052 tsec->create_sid = isec->sid; 4053 return ret; 4054 } 4055 4056 static int selinux_kernel_module_request(char *kmod_name) 4057 { 4058 struct common_audit_data ad; 4059 4060 ad.type = LSM_AUDIT_DATA_KMOD; 4061 ad.u.kmod_name = kmod_name; 4062 4063 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4064 SYSTEM__MODULE_REQUEST, &ad); 4065 } 4066 4067 static int selinux_kernel_module_from_file(struct file *file) 4068 { 4069 struct common_audit_data ad; 4070 struct inode_security_struct *isec; 4071 struct file_security_struct *fsec; 4072 u32 sid = current_sid(); 4073 int rc; 4074 4075 /* init_module */ 4076 if (file == NULL) 4077 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 4078 SYSTEM__MODULE_LOAD, NULL); 4079 4080 /* finit_module */ 4081 4082 ad.type = LSM_AUDIT_DATA_FILE; 4083 ad.u.file = file; 4084 4085 fsec = selinux_file(file); 4086 if (sid != fsec->sid) { 4087 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4088 if (rc) 4089 return rc; 4090 } 4091 4092 isec = inode_security(file_inode(file)); 4093 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 4094 SYSTEM__MODULE_LOAD, &ad); 4095 } 4096 4097 static int selinux_kernel_read_file(struct file *file, 4098 enum kernel_read_file_id id, 4099 bool contents) 4100 { 4101 int rc = 0; 4102 4103 switch (id) { 4104 case READING_MODULE: 4105 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4106 break; 4107 default: 4108 break; 4109 } 4110 4111 return rc; 4112 } 4113 4114 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4115 { 4116 int rc = 0; 4117 4118 switch (id) { 4119 case LOADING_MODULE: 4120 rc = selinux_kernel_module_from_file(NULL); 4121 break; 4122 default: 4123 break; 4124 } 4125 4126 return rc; 4127 } 4128 4129 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4130 { 4131 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4132 PROCESS__SETPGID, NULL); 4133 } 4134 4135 static int selinux_task_getpgid(struct task_struct *p) 4136 { 4137 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4138 PROCESS__GETPGID, NULL); 4139 } 4140 4141 static int selinux_task_getsid(struct task_struct *p) 4142 { 4143 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4144 PROCESS__GETSESSION, NULL); 4145 } 4146 4147 static void selinux_current_getsecid_subj(u32 *secid) 4148 { 4149 *secid = current_sid(); 4150 } 4151 4152 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) 4153 { 4154 *secid = task_sid_obj(p); 4155 } 4156 4157 static int selinux_task_setnice(struct task_struct *p, int nice) 4158 { 4159 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4160 PROCESS__SETSCHED, NULL); 4161 } 4162 4163 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4164 { 4165 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4166 PROCESS__SETSCHED, NULL); 4167 } 4168 4169 static int selinux_task_getioprio(struct task_struct *p) 4170 { 4171 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4172 PROCESS__GETSCHED, NULL); 4173 } 4174 4175 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4176 unsigned int flags) 4177 { 4178 u32 av = 0; 4179 4180 if (!flags) 4181 return 0; 4182 if (flags & LSM_PRLIMIT_WRITE) 4183 av |= PROCESS__SETRLIMIT; 4184 if (flags & LSM_PRLIMIT_READ) 4185 av |= PROCESS__GETRLIMIT; 4186 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4187 SECCLASS_PROCESS, av, NULL); 4188 } 4189 4190 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4191 struct rlimit *new_rlim) 4192 { 4193 struct rlimit *old_rlim = p->signal->rlim + resource; 4194 4195 /* Control the ability to change the hard limit (whether 4196 lowering or raising it), so that the hard limit can 4197 later be used as a safe reset point for the soft limit 4198 upon context transitions. See selinux_bprm_committing_creds. */ 4199 if (old_rlim->rlim_max != new_rlim->rlim_max) 4200 return avc_has_perm(current_sid(), task_sid_obj(p), 4201 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4202 4203 return 0; 4204 } 4205 4206 static int selinux_task_setscheduler(struct task_struct *p) 4207 { 4208 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4209 PROCESS__SETSCHED, NULL); 4210 } 4211 4212 static int selinux_task_getscheduler(struct task_struct *p) 4213 { 4214 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4215 PROCESS__GETSCHED, NULL); 4216 } 4217 4218 static int selinux_task_movememory(struct task_struct *p) 4219 { 4220 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4221 PROCESS__SETSCHED, NULL); 4222 } 4223 4224 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4225 int sig, const struct cred *cred) 4226 { 4227 u32 secid; 4228 u32 perm; 4229 4230 if (!sig) 4231 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4232 else 4233 perm = signal_to_av(sig); 4234 if (!cred) 4235 secid = current_sid(); 4236 else 4237 secid = cred_sid(cred); 4238 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4239 } 4240 4241 static void selinux_task_to_inode(struct task_struct *p, 4242 struct inode *inode) 4243 { 4244 struct inode_security_struct *isec = selinux_inode(inode); 4245 u32 sid = task_sid_obj(p); 4246 4247 spin_lock(&isec->lock); 4248 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4249 isec->sid = sid; 4250 isec->initialized = LABEL_INITIALIZED; 4251 spin_unlock(&isec->lock); 4252 } 4253 4254 static int selinux_userns_create(const struct cred *cred) 4255 { 4256 u32 sid = current_sid(); 4257 4258 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4259 USER_NAMESPACE__CREATE, NULL); 4260 } 4261 4262 /* Returns error only if unable to parse addresses */ 4263 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4264 struct common_audit_data *ad, u8 *proto) 4265 { 4266 int offset, ihlen, ret = -EINVAL; 4267 struct iphdr _iph, *ih; 4268 4269 offset = skb_network_offset(skb); 4270 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4271 if (ih == NULL) 4272 goto out; 4273 4274 ihlen = ih->ihl * 4; 4275 if (ihlen < sizeof(_iph)) 4276 goto out; 4277 4278 ad->u.net->v4info.saddr = ih->saddr; 4279 ad->u.net->v4info.daddr = ih->daddr; 4280 ret = 0; 4281 4282 if (proto) 4283 *proto = ih->protocol; 4284 4285 switch (ih->protocol) { 4286 case IPPROTO_TCP: { 4287 struct tcphdr _tcph, *th; 4288 4289 if (ntohs(ih->frag_off) & IP_OFFSET) 4290 break; 4291 4292 offset += ihlen; 4293 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4294 if (th == NULL) 4295 break; 4296 4297 ad->u.net->sport = th->source; 4298 ad->u.net->dport = th->dest; 4299 break; 4300 } 4301 4302 case IPPROTO_UDP: { 4303 struct udphdr _udph, *uh; 4304 4305 if (ntohs(ih->frag_off) & IP_OFFSET) 4306 break; 4307 4308 offset += ihlen; 4309 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4310 if (uh == NULL) 4311 break; 4312 4313 ad->u.net->sport = uh->source; 4314 ad->u.net->dport = uh->dest; 4315 break; 4316 } 4317 4318 case IPPROTO_DCCP: { 4319 struct dccp_hdr _dccph, *dh; 4320 4321 if (ntohs(ih->frag_off) & IP_OFFSET) 4322 break; 4323 4324 offset += ihlen; 4325 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4326 if (dh == NULL) 4327 break; 4328 4329 ad->u.net->sport = dh->dccph_sport; 4330 ad->u.net->dport = dh->dccph_dport; 4331 break; 4332 } 4333 4334 #if IS_ENABLED(CONFIG_IP_SCTP) 4335 case IPPROTO_SCTP: { 4336 struct sctphdr _sctph, *sh; 4337 4338 if (ntohs(ih->frag_off) & IP_OFFSET) 4339 break; 4340 4341 offset += ihlen; 4342 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4343 if (sh == NULL) 4344 break; 4345 4346 ad->u.net->sport = sh->source; 4347 ad->u.net->dport = sh->dest; 4348 break; 4349 } 4350 #endif 4351 default: 4352 break; 4353 } 4354 out: 4355 return ret; 4356 } 4357 4358 #if IS_ENABLED(CONFIG_IPV6) 4359 4360 /* Returns error only if unable to parse addresses */ 4361 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4362 struct common_audit_data *ad, u8 *proto) 4363 { 4364 u8 nexthdr; 4365 int ret = -EINVAL, offset; 4366 struct ipv6hdr _ipv6h, *ip6; 4367 __be16 frag_off; 4368 4369 offset = skb_network_offset(skb); 4370 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4371 if (ip6 == NULL) 4372 goto out; 4373 4374 ad->u.net->v6info.saddr = ip6->saddr; 4375 ad->u.net->v6info.daddr = ip6->daddr; 4376 ret = 0; 4377 4378 nexthdr = ip6->nexthdr; 4379 offset += sizeof(_ipv6h); 4380 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4381 if (offset < 0) 4382 goto out; 4383 4384 if (proto) 4385 *proto = nexthdr; 4386 4387 switch (nexthdr) { 4388 case IPPROTO_TCP: { 4389 struct tcphdr _tcph, *th; 4390 4391 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4392 if (th == NULL) 4393 break; 4394 4395 ad->u.net->sport = th->source; 4396 ad->u.net->dport = th->dest; 4397 break; 4398 } 4399 4400 case IPPROTO_UDP: { 4401 struct udphdr _udph, *uh; 4402 4403 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4404 if (uh == NULL) 4405 break; 4406 4407 ad->u.net->sport = uh->source; 4408 ad->u.net->dport = uh->dest; 4409 break; 4410 } 4411 4412 case IPPROTO_DCCP: { 4413 struct dccp_hdr _dccph, *dh; 4414 4415 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4416 if (dh == NULL) 4417 break; 4418 4419 ad->u.net->sport = dh->dccph_sport; 4420 ad->u.net->dport = dh->dccph_dport; 4421 break; 4422 } 4423 4424 #if IS_ENABLED(CONFIG_IP_SCTP) 4425 case IPPROTO_SCTP: { 4426 struct sctphdr _sctph, *sh; 4427 4428 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4429 if (sh == NULL) 4430 break; 4431 4432 ad->u.net->sport = sh->source; 4433 ad->u.net->dport = sh->dest; 4434 break; 4435 } 4436 #endif 4437 /* includes fragments */ 4438 default: 4439 break; 4440 } 4441 out: 4442 return ret; 4443 } 4444 4445 #endif /* IPV6 */ 4446 4447 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4448 char **_addrp, int src, u8 *proto) 4449 { 4450 char *addrp; 4451 int ret; 4452 4453 switch (ad->u.net->family) { 4454 case PF_INET: 4455 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4456 if (ret) 4457 goto parse_error; 4458 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4459 &ad->u.net->v4info.daddr); 4460 goto okay; 4461 4462 #if IS_ENABLED(CONFIG_IPV6) 4463 case PF_INET6: 4464 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4465 if (ret) 4466 goto parse_error; 4467 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4468 &ad->u.net->v6info.daddr); 4469 goto okay; 4470 #endif /* IPV6 */ 4471 default: 4472 addrp = NULL; 4473 goto okay; 4474 } 4475 4476 parse_error: 4477 pr_warn( 4478 "SELinux: failure in selinux_parse_skb()," 4479 " unable to parse packet\n"); 4480 return ret; 4481 4482 okay: 4483 if (_addrp) 4484 *_addrp = addrp; 4485 return 0; 4486 } 4487 4488 /** 4489 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4490 * @skb: the packet 4491 * @family: protocol family 4492 * @sid: the packet's peer label SID 4493 * 4494 * Description: 4495 * Check the various different forms of network peer labeling and determine 4496 * the peer label/SID for the packet; most of the magic actually occurs in 4497 * the security server function security_net_peersid_cmp(). The function 4498 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4499 * or -EACCES if @sid is invalid due to inconsistencies with the different 4500 * peer labels. 4501 * 4502 */ 4503 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4504 { 4505 int err; 4506 u32 xfrm_sid; 4507 u32 nlbl_sid; 4508 u32 nlbl_type; 4509 4510 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4511 if (unlikely(err)) 4512 return -EACCES; 4513 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4514 if (unlikely(err)) 4515 return -EACCES; 4516 4517 err = security_net_peersid_resolve(nlbl_sid, 4518 nlbl_type, xfrm_sid, sid); 4519 if (unlikely(err)) { 4520 pr_warn( 4521 "SELinux: failure in selinux_skb_peerlbl_sid()," 4522 " unable to determine packet's peer label\n"); 4523 return -EACCES; 4524 } 4525 4526 return 0; 4527 } 4528 4529 /** 4530 * selinux_conn_sid - Determine the child socket label for a connection 4531 * @sk_sid: the parent socket's SID 4532 * @skb_sid: the packet's SID 4533 * @conn_sid: the resulting connection SID 4534 * 4535 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4536 * combined with the MLS information from @skb_sid in order to create 4537 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4538 * of @sk_sid. Returns zero on success, negative values on failure. 4539 * 4540 */ 4541 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4542 { 4543 int err = 0; 4544 4545 if (skb_sid != SECSID_NULL) 4546 err = security_sid_mls_copy(sk_sid, skb_sid, 4547 conn_sid); 4548 else 4549 *conn_sid = sk_sid; 4550 4551 return err; 4552 } 4553 4554 /* socket security operations */ 4555 4556 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4557 u16 secclass, u32 *socksid) 4558 { 4559 if (tsec->sockcreate_sid > SECSID_NULL) { 4560 *socksid = tsec->sockcreate_sid; 4561 return 0; 4562 } 4563 4564 return security_transition_sid(tsec->sid, tsec->sid, 4565 secclass, NULL, socksid); 4566 } 4567 4568 static int sock_has_perm(struct sock *sk, u32 perms) 4569 { 4570 struct sk_security_struct *sksec = sk->sk_security; 4571 struct common_audit_data ad; 4572 struct lsm_network_audit net; 4573 4574 if (sksec->sid == SECINITSID_KERNEL) 4575 return 0; 4576 4577 ad_net_init_from_sk(&ad, &net, sk); 4578 4579 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4580 &ad); 4581 } 4582 4583 static int selinux_socket_create(int family, int type, 4584 int protocol, int kern) 4585 { 4586 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4587 u32 newsid; 4588 u16 secclass; 4589 int rc; 4590 4591 if (kern) 4592 return 0; 4593 4594 secclass = socket_type_to_security_class(family, type, protocol); 4595 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4596 if (rc) 4597 return rc; 4598 4599 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4600 } 4601 4602 static int selinux_socket_post_create(struct socket *sock, int family, 4603 int type, int protocol, int kern) 4604 { 4605 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4606 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4607 struct sk_security_struct *sksec; 4608 u16 sclass = socket_type_to_security_class(family, type, protocol); 4609 u32 sid = SECINITSID_KERNEL; 4610 int err = 0; 4611 4612 if (!kern) { 4613 err = socket_sockcreate_sid(tsec, sclass, &sid); 4614 if (err) 4615 return err; 4616 } 4617 4618 isec->sclass = sclass; 4619 isec->sid = sid; 4620 isec->initialized = LABEL_INITIALIZED; 4621 4622 if (sock->sk) { 4623 sksec = sock->sk->sk_security; 4624 sksec->sclass = sclass; 4625 sksec->sid = sid; 4626 /* Allows detection of the first association on this socket */ 4627 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4628 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4629 4630 err = selinux_netlbl_socket_post_create(sock->sk, family); 4631 } 4632 4633 return err; 4634 } 4635 4636 static int selinux_socket_socketpair(struct socket *socka, 4637 struct socket *sockb) 4638 { 4639 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4640 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4641 4642 sksec_a->peer_sid = sksec_b->sid; 4643 sksec_b->peer_sid = sksec_a->sid; 4644 4645 return 0; 4646 } 4647 4648 /* Range of port numbers used to automatically bind. 4649 Need to determine whether we should perform a name_bind 4650 permission check between the socket and the port number. */ 4651 4652 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4653 { 4654 struct sock *sk = sock->sk; 4655 struct sk_security_struct *sksec = sk->sk_security; 4656 u16 family; 4657 int err; 4658 4659 err = sock_has_perm(sk, SOCKET__BIND); 4660 if (err) 4661 goto out; 4662 4663 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4664 family = sk->sk_family; 4665 if (family == PF_INET || family == PF_INET6) { 4666 char *addrp; 4667 struct common_audit_data ad; 4668 struct lsm_network_audit net = {0,}; 4669 struct sockaddr_in *addr4 = NULL; 4670 struct sockaddr_in6 *addr6 = NULL; 4671 u16 family_sa; 4672 unsigned short snum; 4673 u32 sid, node_perm; 4674 4675 /* 4676 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4677 * that validates multiple binding addresses. Because of this 4678 * need to check address->sa_family as it is possible to have 4679 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4680 */ 4681 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4682 return -EINVAL; 4683 family_sa = address->sa_family; 4684 switch (family_sa) { 4685 case AF_UNSPEC: 4686 case AF_INET: 4687 if (addrlen < sizeof(struct sockaddr_in)) 4688 return -EINVAL; 4689 addr4 = (struct sockaddr_in *)address; 4690 if (family_sa == AF_UNSPEC) { 4691 if (family == PF_INET6) { 4692 /* Length check from inet6_bind_sk() */ 4693 if (addrlen < SIN6_LEN_RFC2133) 4694 return -EINVAL; 4695 /* Family check from __inet6_bind() */ 4696 goto err_af; 4697 } 4698 /* see __inet_bind(), we only want to allow 4699 * AF_UNSPEC if the address is INADDR_ANY 4700 */ 4701 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4702 goto err_af; 4703 family_sa = AF_INET; 4704 } 4705 snum = ntohs(addr4->sin_port); 4706 addrp = (char *)&addr4->sin_addr.s_addr; 4707 break; 4708 case AF_INET6: 4709 if (addrlen < SIN6_LEN_RFC2133) 4710 return -EINVAL; 4711 addr6 = (struct sockaddr_in6 *)address; 4712 snum = ntohs(addr6->sin6_port); 4713 addrp = (char *)&addr6->sin6_addr.s6_addr; 4714 break; 4715 default: 4716 goto err_af; 4717 } 4718 4719 ad.type = LSM_AUDIT_DATA_NET; 4720 ad.u.net = &net; 4721 ad.u.net->sport = htons(snum); 4722 ad.u.net->family = family_sa; 4723 4724 if (snum) { 4725 int low, high; 4726 4727 inet_get_local_port_range(sock_net(sk), &low, &high); 4728 4729 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4730 snum < low || snum > high) { 4731 err = sel_netport_sid(sk->sk_protocol, 4732 snum, &sid); 4733 if (err) 4734 goto out; 4735 err = avc_has_perm(sksec->sid, sid, 4736 sksec->sclass, 4737 SOCKET__NAME_BIND, &ad); 4738 if (err) 4739 goto out; 4740 } 4741 } 4742 4743 switch (sksec->sclass) { 4744 case SECCLASS_TCP_SOCKET: 4745 node_perm = TCP_SOCKET__NODE_BIND; 4746 break; 4747 4748 case SECCLASS_UDP_SOCKET: 4749 node_perm = UDP_SOCKET__NODE_BIND; 4750 break; 4751 4752 case SECCLASS_DCCP_SOCKET: 4753 node_perm = DCCP_SOCKET__NODE_BIND; 4754 break; 4755 4756 case SECCLASS_SCTP_SOCKET: 4757 node_perm = SCTP_SOCKET__NODE_BIND; 4758 break; 4759 4760 default: 4761 node_perm = RAWIP_SOCKET__NODE_BIND; 4762 break; 4763 } 4764 4765 err = sel_netnode_sid(addrp, family_sa, &sid); 4766 if (err) 4767 goto out; 4768 4769 if (family_sa == AF_INET) 4770 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4771 else 4772 ad.u.net->v6info.saddr = addr6->sin6_addr; 4773 4774 err = avc_has_perm(sksec->sid, sid, 4775 sksec->sclass, node_perm, &ad); 4776 if (err) 4777 goto out; 4778 } 4779 out: 4780 return err; 4781 err_af: 4782 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4783 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4784 return -EINVAL; 4785 return -EAFNOSUPPORT; 4786 } 4787 4788 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4789 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4790 */ 4791 static int selinux_socket_connect_helper(struct socket *sock, 4792 struct sockaddr *address, int addrlen) 4793 { 4794 struct sock *sk = sock->sk; 4795 struct sk_security_struct *sksec = sk->sk_security; 4796 int err; 4797 4798 err = sock_has_perm(sk, SOCKET__CONNECT); 4799 if (err) 4800 return err; 4801 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4802 return -EINVAL; 4803 4804 /* connect(AF_UNSPEC) has special handling, as it is a documented 4805 * way to disconnect the socket 4806 */ 4807 if (address->sa_family == AF_UNSPEC) 4808 return 0; 4809 4810 /* 4811 * If a TCP, DCCP or SCTP socket, check name_connect permission 4812 * for the port. 4813 */ 4814 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4815 sksec->sclass == SECCLASS_DCCP_SOCKET || 4816 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4817 struct common_audit_data ad; 4818 struct lsm_network_audit net = {0,}; 4819 struct sockaddr_in *addr4 = NULL; 4820 struct sockaddr_in6 *addr6 = NULL; 4821 unsigned short snum; 4822 u32 sid, perm; 4823 4824 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4825 * that validates multiple connect addresses. Because of this 4826 * need to check address->sa_family as it is possible to have 4827 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4828 */ 4829 switch (address->sa_family) { 4830 case AF_INET: 4831 addr4 = (struct sockaddr_in *)address; 4832 if (addrlen < sizeof(struct sockaddr_in)) 4833 return -EINVAL; 4834 snum = ntohs(addr4->sin_port); 4835 break; 4836 case AF_INET6: 4837 addr6 = (struct sockaddr_in6 *)address; 4838 if (addrlen < SIN6_LEN_RFC2133) 4839 return -EINVAL; 4840 snum = ntohs(addr6->sin6_port); 4841 break; 4842 default: 4843 /* Note that SCTP services expect -EINVAL, whereas 4844 * others expect -EAFNOSUPPORT. 4845 */ 4846 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4847 return -EINVAL; 4848 else 4849 return -EAFNOSUPPORT; 4850 } 4851 4852 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4853 if (err) 4854 return err; 4855 4856 switch (sksec->sclass) { 4857 case SECCLASS_TCP_SOCKET: 4858 perm = TCP_SOCKET__NAME_CONNECT; 4859 break; 4860 case SECCLASS_DCCP_SOCKET: 4861 perm = DCCP_SOCKET__NAME_CONNECT; 4862 break; 4863 case SECCLASS_SCTP_SOCKET: 4864 perm = SCTP_SOCKET__NAME_CONNECT; 4865 break; 4866 } 4867 4868 ad.type = LSM_AUDIT_DATA_NET; 4869 ad.u.net = &net; 4870 ad.u.net->dport = htons(snum); 4871 ad.u.net->family = address->sa_family; 4872 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4873 if (err) 4874 return err; 4875 } 4876 4877 return 0; 4878 } 4879 4880 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4881 static int selinux_socket_connect(struct socket *sock, 4882 struct sockaddr *address, int addrlen) 4883 { 4884 int err; 4885 struct sock *sk = sock->sk; 4886 4887 err = selinux_socket_connect_helper(sock, address, addrlen); 4888 if (err) 4889 return err; 4890 4891 return selinux_netlbl_socket_connect(sk, address); 4892 } 4893 4894 static int selinux_socket_listen(struct socket *sock, int backlog) 4895 { 4896 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4897 } 4898 4899 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4900 { 4901 int err; 4902 struct inode_security_struct *isec; 4903 struct inode_security_struct *newisec; 4904 u16 sclass; 4905 u32 sid; 4906 4907 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4908 if (err) 4909 return err; 4910 4911 isec = inode_security_novalidate(SOCK_INODE(sock)); 4912 spin_lock(&isec->lock); 4913 sclass = isec->sclass; 4914 sid = isec->sid; 4915 spin_unlock(&isec->lock); 4916 4917 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4918 newisec->sclass = sclass; 4919 newisec->sid = sid; 4920 newisec->initialized = LABEL_INITIALIZED; 4921 4922 return 0; 4923 } 4924 4925 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4926 int size) 4927 { 4928 return sock_has_perm(sock->sk, SOCKET__WRITE); 4929 } 4930 4931 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4932 int size, int flags) 4933 { 4934 return sock_has_perm(sock->sk, SOCKET__READ); 4935 } 4936 4937 static int selinux_socket_getsockname(struct socket *sock) 4938 { 4939 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4940 } 4941 4942 static int selinux_socket_getpeername(struct socket *sock) 4943 { 4944 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4945 } 4946 4947 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4948 { 4949 int err; 4950 4951 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4952 if (err) 4953 return err; 4954 4955 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4956 } 4957 4958 static int selinux_socket_getsockopt(struct socket *sock, int level, 4959 int optname) 4960 { 4961 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4962 } 4963 4964 static int selinux_socket_shutdown(struct socket *sock, int how) 4965 { 4966 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4967 } 4968 4969 static int selinux_socket_unix_stream_connect(struct sock *sock, 4970 struct sock *other, 4971 struct sock *newsk) 4972 { 4973 struct sk_security_struct *sksec_sock = sock->sk_security; 4974 struct sk_security_struct *sksec_other = other->sk_security; 4975 struct sk_security_struct *sksec_new = newsk->sk_security; 4976 struct common_audit_data ad; 4977 struct lsm_network_audit net; 4978 int err; 4979 4980 ad_net_init_from_sk(&ad, &net, other); 4981 4982 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4983 sksec_other->sclass, 4984 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4985 if (err) 4986 return err; 4987 4988 /* server child socket */ 4989 sksec_new->peer_sid = sksec_sock->sid; 4990 err = security_sid_mls_copy(sksec_other->sid, 4991 sksec_sock->sid, &sksec_new->sid); 4992 if (err) 4993 return err; 4994 4995 /* connecting socket */ 4996 sksec_sock->peer_sid = sksec_new->sid; 4997 4998 return 0; 4999 } 5000 5001 static int selinux_socket_unix_may_send(struct socket *sock, 5002 struct socket *other) 5003 { 5004 struct sk_security_struct *ssec = sock->sk->sk_security; 5005 struct sk_security_struct *osec = other->sk->sk_security; 5006 struct common_audit_data ad; 5007 struct lsm_network_audit net; 5008 5009 ad_net_init_from_sk(&ad, &net, other->sk); 5010 5011 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 5012 &ad); 5013 } 5014 5015 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 5016 char *addrp, u16 family, u32 peer_sid, 5017 struct common_audit_data *ad) 5018 { 5019 int err; 5020 u32 if_sid; 5021 u32 node_sid; 5022 5023 err = sel_netif_sid(ns, ifindex, &if_sid); 5024 if (err) 5025 return err; 5026 err = avc_has_perm(peer_sid, if_sid, 5027 SECCLASS_NETIF, NETIF__INGRESS, ad); 5028 if (err) 5029 return err; 5030 5031 err = sel_netnode_sid(addrp, family, &node_sid); 5032 if (err) 5033 return err; 5034 return avc_has_perm(peer_sid, node_sid, 5035 SECCLASS_NODE, NODE__RECVFROM, ad); 5036 } 5037 5038 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5039 u16 family) 5040 { 5041 int err = 0; 5042 struct sk_security_struct *sksec = sk->sk_security; 5043 u32 sk_sid = sksec->sid; 5044 struct common_audit_data ad; 5045 struct lsm_network_audit net; 5046 char *addrp; 5047 5048 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5049 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5050 if (err) 5051 return err; 5052 5053 if (selinux_secmark_enabled()) { 5054 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5055 PACKET__RECV, &ad); 5056 if (err) 5057 return err; 5058 } 5059 5060 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5061 if (err) 5062 return err; 5063 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5064 5065 return err; 5066 } 5067 5068 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5069 { 5070 int err, peerlbl_active, secmark_active; 5071 struct sk_security_struct *sksec = sk->sk_security; 5072 u16 family = sk->sk_family; 5073 u32 sk_sid = sksec->sid; 5074 struct common_audit_data ad; 5075 struct lsm_network_audit net; 5076 char *addrp; 5077 5078 if (family != PF_INET && family != PF_INET6) 5079 return 0; 5080 5081 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5082 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5083 family = PF_INET; 5084 5085 /* If any sort of compatibility mode is enabled then handoff processing 5086 * to the selinux_sock_rcv_skb_compat() function to deal with the 5087 * special handling. We do this in an attempt to keep this function 5088 * as fast and as clean as possible. */ 5089 if (!selinux_policycap_netpeer()) 5090 return selinux_sock_rcv_skb_compat(sk, skb, family); 5091 5092 secmark_active = selinux_secmark_enabled(); 5093 peerlbl_active = selinux_peerlbl_enabled(); 5094 if (!secmark_active && !peerlbl_active) 5095 return 0; 5096 5097 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5098 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5099 if (err) 5100 return err; 5101 5102 if (peerlbl_active) { 5103 u32 peer_sid; 5104 5105 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5106 if (err) 5107 return err; 5108 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5109 addrp, family, peer_sid, &ad); 5110 if (err) { 5111 selinux_netlbl_err(skb, family, err, 0); 5112 return err; 5113 } 5114 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5115 PEER__RECV, &ad); 5116 if (err) { 5117 selinux_netlbl_err(skb, family, err, 0); 5118 return err; 5119 } 5120 } 5121 5122 if (secmark_active) { 5123 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5124 PACKET__RECV, &ad); 5125 if (err) 5126 return err; 5127 } 5128 5129 return err; 5130 } 5131 5132 static int selinux_socket_getpeersec_stream(struct socket *sock, 5133 sockptr_t optval, sockptr_t optlen, 5134 unsigned int len) 5135 { 5136 int err = 0; 5137 char *scontext = NULL; 5138 u32 scontext_len; 5139 struct sk_security_struct *sksec = sock->sk->sk_security; 5140 u32 peer_sid = SECSID_NULL; 5141 5142 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5143 sksec->sclass == SECCLASS_TCP_SOCKET || 5144 sksec->sclass == SECCLASS_SCTP_SOCKET) 5145 peer_sid = sksec->peer_sid; 5146 if (peer_sid == SECSID_NULL) 5147 return -ENOPROTOOPT; 5148 5149 err = security_sid_to_context(peer_sid, &scontext, 5150 &scontext_len); 5151 if (err) 5152 return err; 5153 if (scontext_len > len) { 5154 err = -ERANGE; 5155 goto out_len; 5156 } 5157 5158 if (copy_to_sockptr(optval, scontext, scontext_len)) 5159 err = -EFAULT; 5160 out_len: 5161 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5162 err = -EFAULT; 5163 kfree(scontext); 5164 return err; 5165 } 5166 5167 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5168 { 5169 u32 peer_secid = SECSID_NULL; 5170 u16 family; 5171 struct inode_security_struct *isec; 5172 5173 if (skb && skb->protocol == htons(ETH_P_IP)) 5174 family = PF_INET; 5175 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5176 family = PF_INET6; 5177 else if (sock) 5178 family = sock->sk->sk_family; 5179 else 5180 goto out; 5181 5182 if (sock && family == PF_UNIX) { 5183 isec = inode_security_novalidate(SOCK_INODE(sock)); 5184 peer_secid = isec->sid; 5185 } else if (skb) 5186 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5187 5188 out: 5189 *secid = peer_secid; 5190 if (peer_secid == SECSID_NULL) 5191 return -EINVAL; 5192 return 0; 5193 } 5194 5195 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5196 { 5197 struct sk_security_struct *sksec; 5198 5199 sksec = kzalloc(sizeof(*sksec), priority); 5200 if (!sksec) 5201 return -ENOMEM; 5202 5203 sksec->peer_sid = SECINITSID_UNLABELED; 5204 sksec->sid = SECINITSID_UNLABELED; 5205 sksec->sclass = SECCLASS_SOCKET; 5206 selinux_netlbl_sk_security_reset(sksec); 5207 sk->sk_security = sksec; 5208 5209 return 0; 5210 } 5211 5212 static void selinux_sk_free_security(struct sock *sk) 5213 { 5214 struct sk_security_struct *sksec = sk->sk_security; 5215 5216 sk->sk_security = NULL; 5217 selinux_netlbl_sk_security_free(sksec); 5218 kfree(sksec); 5219 } 5220 5221 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5222 { 5223 struct sk_security_struct *sksec = sk->sk_security; 5224 struct sk_security_struct *newsksec = newsk->sk_security; 5225 5226 newsksec->sid = sksec->sid; 5227 newsksec->peer_sid = sksec->peer_sid; 5228 newsksec->sclass = sksec->sclass; 5229 5230 selinux_netlbl_sk_security_reset(newsksec); 5231 } 5232 5233 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5234 { 5235 if (!sk) 5236 *secid = SECINITSID_ANY_SOCKET; 5237 else { 5238 const struct sk_security_struct *sksec = sk->sk_security; 5239 5240 *secid = sksec->sid; 5241 } 5242 } 5243 5244 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5245 { 5246 struct inode_security_struct *isec = 5247 inode_security_novalidate(SOCK_INODE(parent)); 5248 struct sk_security_struct *sksec = sk->sk_security; 5249 5250 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5251 sk->sk_family == PF_UNIX) 5252 isec->sid = sksec->sid; 5253 sksec->sclass = isec->sclass; 5254 } 5255 5256 /* 5257 * Determines peer_secid for the asoc and updates socket's peer label 5258 * if it's the first association on the socket. 5259 */ 5260 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5261 struct sk_buff *skb) 5262 { 5263 struct sock *sk = asoc->base.sk; 5264 u16 family = sk->sk_family; 5265 struct sk_security_struct *sksec = sk->sk_security; 5266 struct common_audit_data ad; 5267 struct lsm_network_audit net; 5268 int err; 5269 5270 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5271 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5272 family = PF_INET; 5273 5274 if (selinux_peerlbl_enabled()) { 5275 asoc->peer_secid = SECSID_NULL; 5276 5277 /* This will return peer_sid = SECSID_NULL if there are 5278 * no peer labels, see security_net_peersid_resolve(). 5279 */ 5280 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5281 if (err) 5282 return err; 5283 5284 if (asoc->peer_secid == SECSID_NULL) 5285 asoc->peer_secid = SECINITSID_UNLABELED; 5286 } else { 5287 asoc->peer_secid = SECINITSID_UNLABELED; 5288 } 5289 5290 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5291 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5292 5293 /* Here as first association on socket. As the peer SID 5294 * was allowed by peer recv (and the netif/node checks), 5295 * then it is approved by policy and used as the primary 5296 * peer SID for getpeercon(3). 5297 */ 5298 sksec->peer_sid = asoc->peer_secid; 5299 } else if (sksec->peer_sid != asoc->peer_secid) { 5300 /* Other association peer SIDs are checked to enforce 5301 * consistency among the peer SIDs. 5302 */ 5303 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5304 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5305 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5306 &ad); 5307 if (err) 5308 return err; 5309 } 5310 return 0; 5311 } 5312 5313 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5314 * happens on an incoming connect(2), sctp_connectx(3) or 5315 * sctp_sendmsg(3) (with no association already present). 5316 */ 5317 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5318 struct sk_buff *skb) 5319 { 5320 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5321 u32 conn_sid; 5322 int err; 5323 5324 if (!selinux_policycap_extsockclass()) 5325 return 0; 5326 5327 err = selinux_sctp_process_new_assoc(asoc, skb); 5328 if (err) 5329 return err; 5330 5331 /* Compute the MLS component for the connection and store 5332 * the information in asoc. This will be used by SCTP TCP type 5333 * sockets and peeled off connections as they cause a new 5334 * socket to be generated. selinux_sctp_sk_clone() will then 5335 * plug this into the new socket. 5336 */ 5337 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5338 if (err) 5339 return err; 5340 5341 asoc->secid = conn_sid; 5342 5343 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5344 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5345 } 5346 5347 /* Called when SCTP receives a COOKIE ACK chunk as the final 5348 * response to an association request (initited by us). 5349 */ 5350 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5351 struct sk_buff *skb) 5352 { 5353 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5354 5355 if (!selinux_policycap_extsockclass()) 5356 return 0; 5357 5358 /* Inherit secid from the parent socket - this will be picked up 5359 * by selinux_sctp_sk_clone() if the association gets peeled off 5360 * into a new socket. 5361 */ 5362 asoc->secid = sksec->sid; 5363 5364 return selinux_sctp_process_new_assoc(asoc, skb); 5365 } 5366 5367 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5368 * based on their @optname. 5369 */ 5370 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5371 struct sockaddr *address, 5372 int addrlen) 5373 { 5374 int len, err = 0, walk_size = 0; 5375 void *addr_buf; 5376 struct sockaddr *addr; 5377 struct socket *sock; 5378 5379 if (!selinux_policycap_extsockclass()) 5380 return 0; 5381 5382 /* Process one or more addresses that may be IPv4 or IPv6 */ 5383 sock = sk->sk_socket; 5384 addr_buf = address; 5385 5386 while (walk_size < addrlen) { 5387 if (walk_size + sizeof(sa_family_t) > addrlen) 5388 return -EINVAL; 5389 5390 addr = addr_buf; 5391 switch (addr->sa_family) { 5392 case AF_UNSPEC: 5393 case AF_INET: 5394 len = sizeof(struct sockaddr_in); 5395 break; 5396 case AF_INET6: 5397 len = sizeof(struct sockaddr_in6); 5398 break; 5399 default: 5400 return -EINVAL; 5401 } 5402 5403 if (walk_size + len > addrlen) 5404 return -EINVAL; 5405 5406 err = -EINVAL; 5407 switch (optname) { 5408 /* Bind checks */ 5409 case SCTP_PRIMARY_ADDR: 5410 case SCTP_SET_PEER_PRIMARY_ADDR: 5411 case SCTP_SOCKOPT_BINDX_ADD: 5412 err = selinux_socket_bind(sock, addr, len); 5413 break; 5414 /* Connect checks */ 5415 case SCTP_SOCKOPT_CONNECTX: 5416 case SCTP_PARAM_SET_PRIMARY: 5417 case SCTP_PARAM_ADD_IP: 5418 case SCTP_SENDMSG_CONNECT: 5419 err = selinux_socket_connect_helper(sock, addr, len); 5420 if (err) 5421 return err; 5422 5423 /* As selinux_sctp_bind_connect() is called by the 5424 * SCTP protocol layer, the socket is already locked, 5425 * therefore selinux_netlbl_socket_connect_locked() 5426 * is called here. The situations handled are: 5427 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5428 * whenever a new IP address is added or when a new 5429 * primary address is selected. 5430 * Note that an SCTP connect(2) call happens before 5431 * the SCTP protocol layer and is handled via 5432 * selinux_socket_connect(). 5433 */ 5434 err = selinux_netlbl_socket_connect_locked(sk, addr); 5435 break; 5436 } 5437 5438 if (err) 5439 return err; 5440 5441 addr_buf += len; 5442 walk_size += len; 5443 } 5444 5445 return 0; 5446 } 5447 5448 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5449 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5450 struct sock *newsk) 5451 { 5452 struct sk_security_struct *sksec = sk->sk_security; 5453 struct sk_security_struct *newsksec = newsk->sk_security; 5454 5455 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5456 * the non-sctp clone version. 5457 */ 5458 if (!selinux_policycap_extsockclass()) 5459 return selinux_sk_clone_security(sk, newsk); 5460 5461 newsksec->sid = asoc->secid; 5462 newsksec->peer_sid = asoc->peer_secid; 5463 newsksec->sclass = sksec->sclass; 5464 selinux_netlbl_sctp_sk_clone(sk, newsk); 5465 } 5466 5467 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5468 { 5469 struct sk_security_struct *ssksec = ssk->sk_security; 5470 struct sk_security_struct *sksec = sk->sk_security; 5471 5472 ssksec->sclass = sksec->sclass; 5473 ssksec->sid = sksec->sid; 5474 5475 /* replace the existing subflow label deleting the existing one 5476 * and re-recreating a new label using the updated context 5477 */ 5478 selinux_netlbl_sk_security_free(ssksec); 5479 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5480 } 5481 5482 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5483 struct request_sock *req) 5484 { 5485 struct sk_security_struct *sksec = sk->sk_security; 5486 int err; 5487 u16 family = req->rsk_ops->family; 5488 u32 connsid; 5489 u32 peersid; 5490 5491 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5492 if (err) 5493 return err; 5494 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5495 if (err) 5496 return err; 5497 req->secid = connsid; 5498 req->peer_secid = peersid; 5499 5500 return selinux_netlbl_inet_conn_request(req, family); 5501 } 5502 5503 static void selinux_inet_csk_clone(struct sock *newsk, 5504 const struct request_sock *req) 5505 { 5506 struct sk_security_struct *newsksec = newsk->sk_security; 5507 5508 newsksec->sid = req->secid; 5509 newsksec->peer_sid = req->peer_secid; 5510 /* NOTE: Ideally, we should also get the isec->sid for the 5511 new socket in sync, but we don't have the isec available yet. 5512 So we will wait until sock_graft to do it, by which 5513 time it will have been created and available. */ 5514 5515 /* We don't need to take any sort of lock here as we are the only 5516 * thread with access to newsksec */ 5517 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5518 } 5519 5520 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5521 { 5522 u16 family = sk->sk_family; 5523 struct sk_security_struct *sksec = sk->sk_security; 5524 5525 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5526 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5527 family = PF_INET; 5528 5529 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5530 } 5531 5532 static int selinux_secmark_relabel_packet(u32 sid) 5533 { 5534 const struct task_security_struct *tsec; 5535 u32 tsid; 5536 5537 tsec = selinux_cred(current_cred()); 5538 tsid = tsec->sid; 5539 5540 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5541 NULL); 5542 } 5543 5544 static void selinux_secmark_refcount_inc(void) 5545 { 5546 atomic_inc(&selinux_secmark_refcount); 5547 } 5548 5549 static void selinux_secmark_refcount_dec(void) 5550 { 5551 atomic_dec(&selinux_secmark_refcount); 5552 } 5553 5554 static void selinux_req_classify_flow(const struct request_sock *req, 5555 struct flowi_common *flic) 5556 { 5557 flic->flowic_secid = req->secid; 5558 } 5559 5560 static int selinux_tun_dev_alloc_security(void **security) 5561 { 5562 struct tun_security_struct *tunsec; 5563 5564 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5565 if (!tunsec) 5566 return -ENOMEM; 5567 tunsec->sid = current_sid(); 5568 5569 *security = tunsec; 5570 return 0; 5571 } 5572 5573 static void selinux_tun_dev_free_security(void *security) 5574 { 5575 kfree(security); 5576 } 5577 5578 static int selinux_tun_dev_create(void) 5579 { 5580 u32 sid = current_sid(); 5581 5582 /* we aren't taking into account the "sockcreate" SID since the socket 5583 * that is being created here is not a socket in the traditional sense, 5584 * instead it is a private sock, accessible only to the kernel, and 5585 * representing a wide range of network traffic spanning multiple 5586 * connections unlike traditional sockets - check the TUN driver to 5587 * get a better understanding of why this socket is special */ 5588 5589 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5590 NULL); 5591 } 5592 5593 static int selinux_tun_dev_attach_queue(void *security) 5594 { 5595 struct tun_security_struct *tunsec = security; 5596 5597 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5598 TUN_SOCKET__ATTACH_QUEUE, NULL); 5599 } 5600 5601 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5602 { 5603 struct tun_security_struct *tunsec = security; 5604 struct sk_security_struct *sksec = sk->sk_security; 5605 5606 /* we don't currently perform any NetLabel based labeling here and it 5607 * isn't clear that we would want to do so anyway; while we could apply 5608 * labeling without the support of the TUN user the resulting labeled 5609 * traffic from the other end of the connection would almost certainly 5610 * cause confusion to the TUN user that had no idea network labeling 5611 * protocols were being used */ 5612 5613 sksec->sid = tunsec->sid; 5614 sksec->sclass = SECCLASS_TUN_SOCKET; 5615 5616 return 0; 5617 } 5618 5619 static int selinux_tun_dev_open(void *security) 5620 { 5621 struct tun_security_struct *tunsec = security; 5622 u32 sid = current_sid(); 5623 int err; 5624 5625 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5626 TUN_SOCKET__RELABELFROM, NULL); 5627 if (err) 5628 return err; 5629 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5630 TUN_SOCKET__RELABELTO, NULL); 5631 if (err) 5632 return err; 5633 tunsec->sid = sid; 5634 5635 return 0; 5636 } 5637 5638 #ifdef CONFIG_NETFILTER 5639 5640 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5641 const struct nf_hook_state *state) 5642 { 5643 int ifindex; 5644 u16 family; 5645 char *addrp; 5646 u32 peer_sid; 5647 struct common_audit_data ad; 5648 struct lsm_network_audit net; 5649 int secmark_active, peerlbl_active; 5650 5651 if (!selinux_policycap_netpeer()) 5652 return NF_ACCEPT; 5653 5654 secmark_active = selinux_secmark_enabled(); 5655 peerlbl_active = selinux_peerlbl_enabled(); 5656 if (!secmark_active && !peerlbl_active) 5657 return NF_ACCEPT; 5658 5659 family = state->pf; 5660 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5661 return NF_DROP; 5662 5663 ifindex = state->in->ifindex; 5664 ad_net_init_from_iif(&ad, &net, ifindex, family); 5665 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5666 return NF_DROP; 5667 5668 if (peerlbl_active) { 5669 int err; 5670 5671 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5672 addrp, family, peer_sid, &ad); 5673 if (err) { 5674 selinux_netlbl_err(skb, family, err, 1); 5675 return NF_DROP; 5676 } 5677 } 5678 5679 if (secmark_active) 5680 if (avc_has_perm(peer_sid, skb->secmark, 5681 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5682 return NF_DROP; 5683 5684 if (netlbl_enabled()) 5685 /* we do this in the FORWARD path and not the POST_ROUTING 5686 * path because we want to make sure we apply the necessary 5687 * labeling before IPsec is applied so we can leverage AH 5688 * protection */ 5689 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5690 return NF_DROP; 5691 5692 return NF_ACCEPT; 5693 } 5694 5695 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5696 const struct nf_hook_state *state) 5697 { 5698 struct sock *sk; 5699 u32 sid; 5700 5701 if (!netlbl_enabled()) 5702 return NF_ACCEPT; 5703 5704 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5705 * because we want to make sure we apply the necessary labeling 5706 * before IPsec is applied so we can leverage AH protection */ 5707 sk = skb->sk; 5708 if (sk) { 5709 struct sk_security_struct *sksec; 5710 5711 if (sk_listener(sk)) 5712 /* if the socket is the listening state then this 5713 * packet is a SYN-ACK packet which means it needs to 5714 * be labeled based on the connection/request_sock and 5715 * not the parent socket. unfortunately, we can't 5716 * lookup the request_sock yet as it isn't queued on 5717 * the parent socket until after the SYN-ACK is sent. 5718 * the "solution" is to simply pass the packet as-is 5719 * as any IP option based labeling should be copied 5720 * from the initial connection request (in the IP 5721 * layer). it is far from ideal, but until we get a 5722 * security label in the packet itself this is the 5723 * best we can do. */ 5724 return NF_ACCEPT; 5725 5726 /* standard practice, label using the parent socket */ 5727 sksec = sk->sk_security; 5728 sid = sksec->sid; 5729 } else 5730 sid = SECINITSID_KERNEL; 5731 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5732 return NF_DROP; 5733 5734 return NF_ACCEPT; 5735 } 5736 5737 5738 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5739 const struct nf_hook_state *state) 5740 { 5741 struct sock *sk; 5742 struct sk_security_struct *sksec; 5743 struct common_audit_data ad; 5744 struct lsm_network_audit net; 5745 u8 proto = 0; 5746 5747 sk = skb_to_full_sk(skb); 5748 if (sk == NULL) 5749 return NF_ACCEPT; 5750 sksec = sk->sk_security; 5751 5752 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5753 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5754 return NF_DROP; 5755 5756 if (selinux_secmark_enabled()) 5757 if (avc_has_perm(sksec->sid, skb->secmark, 5758 SECCLASS_PACKET, PACKET__SEND, &ad)) 5759 return NF_DROP_ERR(-ECONNREFUSED); 5760 5761 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5762 return NF_DROP_ERR(-ECONNREFUSED); 5763 5764 return NF_ACCEPT; 5765 } 5766 5767 static unsigned int selinux_ip_postroute(void *priv, 5768 struct sk_buff *skb, 5769 const struct nf_hook_state *state) 5770 { 5771 u16 family; 5772 u32 secmark_perm; 5773 u32 peer_sid; 5774 int ifindex; 5775 struct sock *sk; 5776 struct common_audit_data ad; 5777 struct lsm_network_audit net; 5778 char *addrp; 5779 int secmark_active, peerlbl_active; 5780 5781 /* If any sort of compatibility mode is enabled then handoff processing 5782 * to the selinux_ip_postroute_compat() function to deal with the 5783 * special handling. We do this in an attempt to keep this function 5784 * as fast and as clean as possible. */ 5785 if (!selinux_policycap_netpeer()) 5786 return selinux_ip_postroute_compat(skb, state); 5787 5788 secmark_active = selinux_secmark_enabled(); 5789 peerlbl_active = selinux_peerlbl_enabled(); 5790 if (!secmark_active && !peerlbl_active) 5791 return NF_ACCEPT; 5792 5793 sk = skb_to_full_sk(skb); 5794 5795 #ifdef CONFIG_XFRM 5796 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5797 * packet transformation so allow the packet to pass without any checks 5798 * since we'll have another chance to perform access control checks 5799 * when the packet is on it's final way out. 5800 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5801 * is NULL, in this case go ahead and apply access control. 5802 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5803 * TCP listening state we cannot wait until the XFRM processing 5804 * is done as we will miss out on the SA label if we do; 5805 * unfortunately, this means more work, but it is only once per 5806 * connection. */ 5807 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5808 !(sk && sk_listener(sk))) 5809 return NF_ACCEPT; 5810 #endif 5811 5812 family = state->pf; 5813 if (sk == NULL) { 5814 /* Without an associated socket the packet is either coming 5815 * from the kernel or it is being forwarded; check the packet 5816 * to determine which and if the packet is being forwarded 5817 * query the packet directly to determine the security label. */ 5818 if (skb->skb_iif) { 5819 secmark_perm = PACKET__FORWARD_OUT; 5820 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5821 return NF_DROP; 5822 } else { 5823 secmark_perm = PACKET__SEND; 5824 peer_sid = SECINITSID_KERNEL; 5825 } 5826 } else if (sk_listener(sk)) { 5827 /* Locally generated packet but the associated socket is in the 5828 * listening state which means this is a SYN-ACK packet. In 5829 * this particular case the correct security label is assigned 5830 * to the connection/request_sock but unfortunately we can't 5831 * query the request_sock as it isn't queued on the parent 5832 * socket until after the SYN-ACK packet is sent; the only 5833 * viable choice is to regenerate the label like we do in 5834 * selinux_inet_conn_request(). See also selinux_ip_output() 5835 * for similar problems. */ 5836 u32 skb_sid; 5837 struct sk_security_struct *sksec; 5838 5839 sksec = sk->sk_security; 5840 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5841 return NF_DROP; 5842 /* At this point, if the returned skb peerlbl is SECSID_NULL 5843 * and the packet has been through at least one XFRM 5844 * transformation then we must be dealing with the "final" 5845 * form of labeled IPsec packet; since we've already applied 5846 * all of our access controls on this packet we can safely 5847 * pass the packet. */ 5848 if (skb_sid == SECSID_NULL) { 5849 switch (family) { 5850 case PF_INET: 5851 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5852 return NF_ACCEPT; 5853 break; 5854 case PF_INET6: 5855 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5856 return NF_ACCEPT; 5857 break; 5858 default: 5859 return NF_DROP_ERR(-ECONNREFUSED); 5860 } 5861 } 5862 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5863 return NF_DROP; 5864 secmark_perm = PACKET__SEND; 5865 } else { 5866 /* Locally generated packet, fetch the security label from the 5867 * associated socket. */ 5868 struct sk_security_struct *sksec = sk->sk_security; 5869 peer_sid = sksec->sid; 5870 secmark_perm = PACKET__SEND; 5871 } 5872 5873 ifindex = state->out->ifindex; 5874 ad_net_init_from_iif(&ad, &net, ifindex, family); 5875 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5876 return NF_DROP; 5877 5878 if (secmark_active) 5879 if (avc_has_perm(peer_sid, skb->secmark, 5880 SECCLASS_PACKET, secmark_perm, &ad)) 5881 return NF_DROP_ERR(-ECONNREFUSED); 5882 5883 if (peerlbl_active) { 5884 u32 if_sid; 5885 u32 node_sid; 5886 5887 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5888 return NF_DROP; 5889 if (avc_has_perm(peer_sid, if_sid, 5890 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5891 return NF_DROP_ERR(-ECONNREFUSED); 5892 5893 if (sel_netnode_sid(addrp, family, &node_sid)) 5894 return NF_DROP; 5895 if (avc_has_perm(peer_sid, node_sid, 5896 SECCLASS_NODE, NODE__SENDTO, &ad)) 5897 return NF_DROP_ERR(-ECONNREFUSED); 5898 } 5899 5900 return NF_ACCEPT; 5901 } 5902 #endif /* CONFIG_NETFILTER */ 5903 5904 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5905 { 5906 int rc = 0; 5907 unsigned int msg_len; 5908 unsigned int data_len = skb->len; 5909 unsigned char *data = skb->data; 5910 struct nlmsghdr *nlh; 5911 struct sk_security_struct *sksec = sk->sk_security; 5912 u16 sclass = sksec->sclass; 5913 u32 perm; 5914 5915 while (data_len >= nlmsg_total_size(0)) { 5916 nlh = (struct nlmsghdr *)data; 5917 5918 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5919 * users which means we can't reject skb's with bogus 5920 * length fields; our solution is to follow what 5921 * netlink_rcv_skb() does and simply skip processing at 5922 * messages with length fields that are clearly junk 5923 */ 5924 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5925 return 0; 5926 5927 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5928 if (rc == 0) { 5929 rc = sock_has_perm(sk, perm); 5930 if (rc) 5931 return rc; 5932 } else if (rc == -EINVAL) { 5933 /* -EINVAL is a missing msg/perm mapping */ 5934 pr_warn_ratelimited("SELinux: unrecognized netlink" 5935 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5936 " pid=%d comm=%s\n", 5937 sk->sk_protocol, nlh->nlmsg_type, 5938 secclass_map[sclass - 1].name, 5939 task_pid_nr(current), current->comm); 5940 if (enforcing_enabled() && 5941 !security_get_allow_unknown()) 5942 return rc; 5943 rc = 0; 5944 } else if (rc == -ENOENT) { 5945 /* -ENOENT is a missing socket/class mapping, ignore */ 5946 rc = 0; 5947 } else { 5948 return rc; 5949 } 5950 5951 /* move to the next message after applying netlink padding */ 5952 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5953 if (msg_len >= data_len) 5954 return 0; 5955 data_len -= msg_len; 5956 data += msg_len; 5957 } 5958 5959 return rc; 5960 } 5961 5962 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5963 { 5964 isec->sclass = sclass; 5965 isec->sid = current_sid(); 5966 } 5967 5968 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5969 u32 perms) 5970 { 5971 struct ipc_security_struct *isec; 5972 struct common_audit_data ad; 5973 u32 sid = current_sid(); 5974 5975 isec = selinux_ipc(ipc_perms); 5976 5977 ad.type = LSM_AUDIT_DATA_IPC; 5978 ad.u.ipc_id = ipc_perms->key; 5979 5980 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 5981 } 5982 5983 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5984 { 5985 struct msg_security_struct *msec; 5986 5987 msec = selinux_msg_msg(msg); 5988 msec->sid = SECINITSID_UNLABELED; 5989 5990 return 0; 5991 } 5992 5993 /* message queue security operations */ 5994 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5995 { 5996 struct ipc_security_struct *isec; 5997 struct common_audit_data ad; 5998 u32 sid = current_sid(); 5999 6000 isec = selinux_ipc(msq); 6001 ipc_init_security(isec, SECCLASS_MSGQ); 6002 6003 ad.type = LSM_AUDIT_DATA_IPC; 6004 ad.u.ipc_id = msq->key; 6005 6006 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6007 MSGQ__CREATE, &ad); 6008 } 6009 6010 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 6011 { 6012 struct ipc_security_struct *isec; 6013 struct common_audit_data ad; 6014 u32 sid = current_sid(); 6015 6016 isec = selinux_ipc(msq); 6017 6018 ad.type = LSM_AUDIT_DATA_IPC; 6019 ad.u.ipc_id = msq->key; 6020 6021 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6022 MSGQ__ASSOCIATE, &ad); 6023 } 6024 6025 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 6026 { 6027 u32 perms; 6028 6029 switch (cmd) { 6030 case IPC_INFO: 6031 case MSG_INFO: 6032 /* No specific object, just general system-wide information. */ 6033 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6034 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6035 case IPC_STAT: 6036 case MSG_STAT: 6037 case MSG_STAT_ANY: 6038 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6039 break; 6040 case IPC_SET: 6041 perms = MSGQ__SETATTR; 6042 break; 6043 case IPC_RMID: 6044 perms = MSGQ__DESTROY; 6045 break; 6046 default: 6047 return 0; 6048 } 6049 6050 return ipc_has_perm(msq, perms); 6051 } 6052 6053 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6054 { 6055 struct ipc_security_struct *isec; 6056 struct msg_security_struct *msec; 6057 struct common_audit_data ad; 6058 u32 sid = current_sid(); 6059 int rc; 6060 6061 isec = selinux_ipc(msq); 6062 msec = selinux_msg_msg(msg); 6063 6064 /* 6065 * First time through, need to assign label to the message 6066 */ 6067 if (msec->sid == SECINITSID_UNLABELED) { 6068 /* 6069 * Compute new sid based on current process and 6070 * message queue this message will be stored in 6071 */ 6072 rc = security_transition_sid(sid, isec->sid, 6073 SECCLASS_MSG, NULL, &msec->sid); 6074 if (rc) 6075 return rc; 6076 } 6077 6078 ad.type = LSM_AUDIT_DATA_IPC; 6079 ad.u.ipc_id = msq->key; 6080 6081 /* Can this process write to the queue? */ 6082 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6083 MSGQ__WRITE, &ad); 6084 if (!rc) 6085 /* Can this process send the message */ 6086 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6087 MSG__SEND, &ad); 6088 if (!rc) 6089 /* Can the message be put in the queue? */ 6090 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6091 MSGQ__ENQUEUE, &ad); 6092 6093 return rc; 6094 } 6095 6096 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6097 struct task_struct *target, 6098 long type, int mode) 6099 { 6100 struct ipc_security_struct *isec; 6101 struct msg_security_struct *msec; 6102 struct common_audit_data ad; 6103 u32 sid = task_sid_obj(target); 6104 int rc; 6105 6106 isec = selinux_ipc(msq); 6107 msec = selinux_msg_msg(msg); 6108 6109 ad.type = LSM_AUDIT_DATA_IPC; 6110 ad.u.ipc_id = msq->key; 6111 6112 rc = avc_has_perm(sid, isec->sid, 6113 SECCLASS_MSGQ, MSGQ__READ, &ad); 6114 if (!rc) 6115 rc = avc_has_perm(sid, msec->sid, 6116 SECCLASS_MSG, MSG__RECEIVE, &ad); 6117 return rc; 6118 } 6119 6120 /* Shared Memory security operations */ 6121 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6122 { 6123 struct ipc_security_struct *isec; 6124 struct common_audit_data ad; 6125 u32 sid = current_sid(); 6126 6127 isec = selinux_ipc(shp); 6128 ipc_init_security(isec, SECCLASS_SHM); 6129 6130 ad.type = LSM_AUDIT_DATA_IPC; 6131 ad.u.ipc_id = shp->key; 6132 6133 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6134 SHM__CREATE, &ad); 6135 } 6136 6137 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6138 { 6139 struct ipc_security_struct *isec; 6140 struct common_audit_data ad; 6141 u32 sid = current_sid(); 6142 6143 isec = selinux_ipc(shp); 6144 6145 ad.type = LSM_AUDIT_DATA_IPC; 6146 ad.u.ipc_id = shp->key; 6147 6148 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6149 SHM__ASSOCIATE, &ad); 6150 } 6151 6152 /* Note, at this point, shp is locked down */ 6153 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6154 { 6155 u32 perms; 6156 6157 switch (cmd) { 6158 case IPC_INFO: 6159 case SHM_INFO: 6160 /* No specific object, just general system-wide information. */ 6161 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6162 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6163 case IPC_STAT: 6164 case SHM_STAT: 6165 case SHM_STAT_ANY: 6166 perms = SHM__GETATTR | SHM__ASSOCIATE; 6167 break; 6168 case IPC_SET: 6169 perms = SHM__SETATTR; 6170 break; 6171 case SHM_LOCK: 6172 case SHM_UNLOCK: 6173 perms = SHM__LOCK; 6174 break; 6175 case IPC_RMID: 6176 perms = SHM__DESTROY; 6177 break; 6178 default: 6179 return 0; 6180 } 6181 6182 return ipc_has_perm(shp, perms); 6183 } 6184 6185 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6186 char __user *shmaddr, int shmflg) 6187 { 6188 u32 perms; 6189 6190 if (shmflg & SHM_RDONLY) 6191 perms = SHM__READ; 6192 else 6193 perms = SHM__READ | SHM__WRITE; 6194 6195 return ipc_has_perm(shp, perms); 6196 } 6197 6198 /* Semaphore security operations */ 6199 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6200 { 6201 struct ipc_security_struct *isec; 6202 struct common_audit_data ad; 6203 u32 sid = current_sid(); 6204 6205 isec = selinux_ipc(sma); 6206 ipc_init_security(isec, SECCLASS_SEM); 6207 6208 ad.type = LSM_AUDIT_DATA_IPC; 6209 ad.u.ipc_id = sma->key; 6210 6211 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6212 SEM__CREATE, &ad); 6213 } 6214 6215 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6216 { 6217 struct ipc_security_struct *isec; 6218 struct common_audit_data ad; 6219 u32 sid = current_sid(); 6220 6221 isec = selinux_ipc(sma); 6222 6223 ad.type = LSM_AUDIT_DATA_IPC; 6224 ad.u.ipc_id = sma->key; 6225 6226 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6227 SEM__ASSOCIATE, &ad); 6228 } 6229 6230 /* Note, at this point, sma is locked down */ 6231 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6232 { 6233 int err; 6234 u32 perms; 6235 6236 switch (cmd) { 6237 case IPC_INFO: 6238 case SEM_INFO: 6239 /* No specific object, just general system-wide information. */ 6240 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6241 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6242 case GETPID: 6243 case GETNCNT: 6244 case GETZCNT: 6245 perms = SEM__GETATTR; 6246 break; 6247 case GETVAL: 6248 case GETALL: 6249 perms = SEM__READ; 6250 break; 6251 case SETVAL: 6252 case SETALL: 6253 perms = SEM__WRITE; 6254 break; 6255 case IPC_RMID: 6256 perms = SEM__DESTROY; 6257 break; 6258 case IPC_SET: 6259 perms = SEM__SETATTR; 6260 break; 6261 case IPC_STAT: 6262 case SEM_STAT: 6263 case SEM_STAT_ANY: 6264 perms = SEM__GETATTR | SEM__ASSOCIATE; 6265 break; 6266 default: 6267 return 0; 6268 } 6269 6270 err = ipc_has_perm(sma, perms); 6271 return err; 6272 } 6273 6274 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6275 struct sembuf *sops, unsigned nsops, int alter) 6276 { 6277 u32 perms; 6278 6279 if (alter) 6280 perms = SEM__READ | SEM__WRITE; 6281 else 6282 perms = SEM__READ; 6283 6284 return ipc_has_perm(sma, perms); 6285 } 6286 6287 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6288 { 6289 u32 av = 0; 6290 6291 av = 0; 6292 if (flag & S_IRUGO) 6293 av |= IPC__UNIX_READ; 6294 if (flag & S_IWUGO) 6295 av |= IPC__UNIX_WRITE; 6296 6297 if (av == 0) 6298 return 0; 6299 6300 return ipc_has_perm(ipcp, av); 6301 } 6302 6303 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6304 { 6305 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6306 *secid = isec->sid; 6307 } 6308 6309 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6310 { 6311 if (inode) 6312 inode_doinit_with_dentry(inode, dentry); 6313 } 6314 6315 static int selinux_getprocattr(struct task_struct *p, 6316 const char *name, char **value) 6317 { 6318 const struct task_security_struct *__tsec; 6319 u32 sid; 6320 int error; 6321 unsigned len; 6322 6323 rcu_read_lock(); 6324 __tsec = selinux_cred(__task_cred(p)); 6325 6326 if (current != p) { 6327 error = avc_has_perm(current_sid(), __tsec->sid, 6328 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6329 if (error) 6330 goto bad; 6331 } 6332 6333 if (!strcmp(name, "current")) 6334 sid = __tsec->sid; 6335 else if (!strcmp(name, "prev")) 6336 sid = __tsec->osid; 6337 else if (!strcmp(name, "exec")) 6338 sid = __tsec->exec_sid; 6339 else if (!strcmp(name, "fscreate")) 6340 sid = __tsec->create_sid; 6341 else if (!strcmp(name, "keycreate")) 6342 sid = __tsec->keycreate_sid; 6343 else if (!strcmp(name, "sockcreate")) 6344 sid = __tsec->sockcreate_sid; 6345 else { 6346 error = -EINVAL; 6347 goto bad; 6348 } 6349 rcu_read_unlock(); 6350 6351 if (!sid) 6352 return 0; 6353 6354 error = security_sid_to_context(sid, value, &len); 6355 if (error) 6356 return error; 6357 return len; 6358 6359 bad: 6360 rcu_read_unlock(); 6361 return error; 6362 } 6363 6364 static int selinux_setprocattr(const char *name, void *value, size_t size) 6365 { 6366 struct task_security_struct *tsec; 6367 struct cred *new; 6368 u32 mysid = current_sid(), sid = 0, ptsid; 6369 int error; 6370 char *str = value; 6371 6372 /* 6373 * Basic control over ability to set these attributes at all. 6374 */ 6375 if (!strcmp(name, "exec")) 6376 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6377 PROCESS__SETEXEC, NULL); 6378 else if (!strcmp(name, "fscreate")) 6379 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6380 PROCESS__SETFSCREATE, NULL); 6381 else if (!strcmp(name, "keycreate")) 6382 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6383 PROCESS__SETKEYCREATE, NULL); 6384 else if (!strcmp(name, "sockcreate")) 6385 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6386 PROCESS__SETSOCKCREATE, NULL); 6387 else if (!strcmp(name, "current")) 6388 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6389 PROCESS__SETCURRENT, NULL); 6390 else 6391 error = -EINVAL; 6392 if (error) 6393 return error; 6394 6395 /* Obtain a SID for the context, if one was specified. */ 6396 if (size && str[0] && str[0] != '\n') { 6397 if (str[size-1] == '\n') { 6398 str[size-1] = 0; 6399 size--; 6400 } 6401 error = security_context_to_sid(value, size, 6402 &sid, GFP_KERNEL); 6403 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6404 if (!has_cap_mac_admin(true)) { 6405 struct audit_buffer *ab; 6406 size_t audit_size; 6407 6408 /* We strip a nul only if it is at the end, otherwise the 6409 * context contains a nul and we should audit that */ 6410 if (str[size - 1] == '\0') 6411 audit_size = size - 1; 6412 else 6413 audit_size = size; 6414 ab = audit_log_start(audit_context(), 6415 GFP_ATOMIC, 6416 AUDIT_SELINUX_ERR); 6417 if (!ab) 6418 return error; 6419 audit_log_format(ab, "op=fscreate invalid_context="); 6420 audit_log_n_untrustedstring(ab, value, audit_size); 6421 audit_log_end(ab); 6422 6423 return error; 6424 } 6425 error = security_context_to_sid_force(value, size, 6426 &sid); 6427 } 6428 if (error) 6429 return error; 6430 } 6431 6432 new = prepare_creds(); 6433 if (!new) 6434 return -ENOMEM; 6435 6436 /* Permission checking based on the specified context is 6437 performed during the actual operation (execve, 6438 open/mkdir/...), when we know the full context of the 6439 operation. See selinux_bprm_creds_for_exec for the execve 6440 checks and may_create for the file creation checks. The 6441 operation will then fail if the context is not permitted. */ 6442 tsec = selinux_cred(new); 6443 if (!strcmp(name, "exec")) { 6444 tsec->exec_sid = sid; 6445 } else if (!strcmp(name, "fscreate")) { 6446 tsec->create_sid = sid; 6447 } else if (!strcmp(name, "keycreate")) { 6448 if (sid) { 6449 error = avc_has_perm(mysid, sid, 6450 SECCLASS_KEY, KEY__CREATE, NULL); 6451 if (error) 6452 goto abort_change; 6453 } 6454 tsec->keycreate_sid = sid; 6455 } else if (!strcmp(name, "sockcreate")) { 6456 tsec->sockcreate_sid = sid; 6457 } else if (!strcmp(name, "current")) { 6458 error = -EINVAL; 6459 if (sid == 0) 6460 goto abort_change; 6461 6462 /* Only allow single threaded processes to change context */ 6463 if (!current_is_single_threaded()) { 6464 error = security_bounded_transition(tsec->sid, sid); 6465 if (error) 6466 goto abort_change; 6467 } 6468 6469 /* Check permissions for the transition. */ 6470 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6471 PROCESS__DYNTRANSITION, NULL); 6472 if (error) 6473 goto abort_change; 6474 6475 /* Check for ptracing, and update the task SID if ok. 6476 Otherwise, leave SID unchanged and fail. */ 6477 ptsid = ptrace_parent_sid(); 6478 if (ptsid != 0) { 6479 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6480 PROCESS__PTRACE, NULL); 6481 if (error) 6482 goto abort_change; 6483 } 6484 6485 tsec->sid = sid; 6486 } else { 6487 error = -EINVAL; 6488 goto abort_change; 6489 } 6490 6491 commit_creds(new); 6492 return size; 6493 6494 abort_change: 6495 abort_creds(new); 6496 return error; 6497 } 6498 6499 static int selinux_ismaclabel(const char *name) 6500 { 6501 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6502 } 6503 6504 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6505 { 6506 return security_sid_to_context(secid, 6507 secdata, seclen); 6508 } 6509 6510 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6511 { 6512 return security_context_to_sid(secdata, seclen, 6513 secid, GFP_KERNEL); 6514 } 6515 6516 static void selinux_release_secctx(char *secdata, u32 seclen) 6517 { 6518 kfree(secdata); 6519 } 6520 6521 static void selinux_inode_invalidate_secctx(struct inode *inode) 6522 { 6523 struct inode_security_struct *isec = selinux_inode(inode); 6524 6525 spin_lock(&isec->lock); 6526 isec->initialized = LABEL_INVALID; 6527 spin_unlock(&isec->lock); 6528 } 6529 6530 /* 6531 * called with inode->i_mutex locked 6532 */ 6533 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6534 { 6535 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6536 ctx, ctxlen, 0); 6537 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6538 return rc == -EOPNOTSUPP ? 0 : rc; 6539 } 6540 6541 /* 6542 * called with inode->i_mutex locked 6543 */ 6544 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6545 { 6546 return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6547 ctx, ctxlen, 0); 6548 } 6549 6550 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6551 { 6552 int len = 0; 6553 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6554 XATTR_SELINUX_SUFFIX, ctx, true); 6555 if (len < 0) 6556 return len; 6557 *ctxlen = len; 6558 return 0; 6559 } 6560 #ifdef CONFIG_KEYS 6561 6562 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6563 unsigned long flags) 6564 { 6565 const struct task_security_struct *tsec; 6566 struct key_security_struct *ksec; 6567 6568 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6569 if (!ksec) 6570 return -ENOMEM; 6571 6572 tsec = selinux_cred(cred); 6573 if (tsec->keycreate_sid) 6574 ksec->sid = tsec->keycreate_sid; 6575 else 6576 ksec->sid = tsec->sid; 6577 6578 k->security = ksec; 6579 return 0; 6580 } 6581 6582 static void selinux_key_free(struct key *k) 6583 { 6584 struct key_security_struct *ksec = k->security; 6585 6586 k->security = NULL; 6587 kfree(ksec); 6588 } 6589 6590 static int selinux_key_permission(key_ref_t key_ref, 6591 const struct cred *cred, 6592 enum key_need_perm need_perm) 6593 { 6594 struct key *key; 6595 struct key_security_struct *ksec; 6596 u32 perm, sid; 6597 6598 switch (need_perm) { 6599 case KEY_NEED_VIEW: 6600 perm = KEY__VIEW; 6601 break; 6602 case KEY_NEED_READ: 6603 perm = KEY__READ; 6604 break; 6605 case KEY_NEED_WRITE: 6606 perm = KEY__WRITE; 6607 break; 6608 case KEY_NEED_SEARCH: 6609 perm = KEY__SEARCH; 6610 break; 6611 case KEY_NEED_LINK: 6612 perm = KEY__LINK; 6613 break; 6614 case KEY_NEED_SETATTR: 6615 perm = KEY__SETATTR; 6616 break; 6617 case KEY_NEED_UNLINK: 6618 case KEY_SYSADMIN_OVERRIDE: 6619 case KEY_AUTHTOKEN_OVERRIDE: 6620 case KEY_DEFER_PERM_CHECK: 6621 return 0; 6622 default: 6623 WARN_ON(1); 6624 return -EPERM; 6625 6626 } 6627 6628 sid = cred_sid(cred); 6629 key = key_ref_to_ptr(key_ref); 6630 ksec = key->security; 6631 6632 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6633 } 6634 6635 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6636 { 6637 struct key_security_struct *ksec = key->security; 6638 char *context = NULL; 6639 unsigned len; 6640 int rc; 6641 6642 rc = security_sid_to_context(ksec->sid, 6643 &context, &len); 6644 if (!rc) 6645 rc = len; 6646 *_buffer = context; 6647 return rc; 6648 } 6649 6650 #ifdef CONFIG_KEY_NOTIFICATIONS 6651 static int selinux_watch_key(struct key *key) 6652 { 6653 struct key_security_struct *ksec = key->security; 6654 u32 sid = current_sid(); 6655 6656 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6657 } 6658 #endif 6659 #endif 6660 6661 #ifdef CONFIG_SECURITY_INFINIBAND 6662 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6663 { 6664 struct common_audit_data ad; 6665 int err; 6666 u32 sid = 0; 6667 struct ib_security_struct *sec = ib_sec; 6668 struct lsm_ibpkey_audit ibpkey; 6669 6670 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6671 if (err) 6672 return err; 6673 6674 ad.type = LSM_AUDIT_DATA_IBPKEY; 6675 ibpkey.subnet_prefix = subnet_prefix; 6676 ibpkey.pkey = pkey_val; 6677 ad.u.ibpkey = &ibpkey; 6678 return avc_has_perm(sec->sid, sid, 6679 SECCLASS_INFINIBAND_PKEY, 6680 INFINIBAND_PKEY__ACCESS, &ad); 6681 } 6682 6683 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6684 u8 port_num) 6685 { 6686 struct common_audit_data ad; 6687 int err; 6688 u32 sid = 0; 6689 struct ib_security_struct *sec = ib_sec; 6690 struct lsm_ibendport_audit ibendport; 6691 6692 err = security_ib_endport_sid(dev_name, port_num, 6693 &sid); 6694 6695 if (err) 6696 return err; 6697 6698 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6699 ibendport.dev_name = dev_name; 6700 ibendport.port = port_num; 6701 ad.u.ibendport = &ibendport; 6702 return avc_has_perm(sec->sid, sid, 6703 SECCLASS_INFINIBAND_ENDPORT, 6704 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6705 } 6706 6707 static int selinux_ib_alloc_security(void **ib_sec) 6708 { 6709 struct ib_security_struct *sec; 6710 6711 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6712 if (!sec) 6713 return -ENOMEM; 6714 sec->sid = current_sid(); 6715 6716 *ib_sec = sec; 6717 return 0; 6718 } 6719 6720 static void selinux_ib_free_security(void *ib_sec) 6721 { 6722 kfree(ib_sec); 6723 } 6724 #endif 6725 6726 #ifdef CONFIG_BPF_SYSCALL 6727 static int selinux_bpf(int cmd, union bpf_attr *attr, 6728 unsigned int size) 6729 { 6730 u32 sid = current_sid(); 6731 int ret; 6732 6733 switch (cmd) { 6734 case BPF_MAP_CREATE: 6735 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6736 NULL); 6737 break; 6738 case BPF_PROG_LOAD: 6739 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6740 NULL); 6741 break; 6742 default: 6743 ret = 0; 6744 break; 6745 } 6746 6747 return ret; 6748 } 6749 6750 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6751 { 6752 u32 av = 0; 6753 6754 if (fmode & FMODE_READ) 6755 av |= BPF__MAP_READ; 6756 if (fmode & FMODE_WRITE) 6757 av |= BPF__MAP_WRITE; 6758 return av; 6759 } 6760 6761 /* This function will check the file pass through unix socket or binder to see 6762 * if it is a bpf related object. And apply corresponding checks on the bpf 6763 * object based on the type. The bpf maps and programs, not like other files and 6764 * socket, are using a shared anonymous inode inside the kernel as their inode. 6765 * So checking that inode cannot identify if the process have privilege to 6766 * access the bpf object and that's why we have to add this additional check in 6767 * selinux_file_receive and selinux_binder_transfer_files. 6768 */ 6769 static int bpf_fd_pass(const struct file *file, u32 sid) 6770 { 6771 struct bpf_security_struct *bpfsec; 6772 struct bpf_prog *prog; 6773 struct bpf_map *map; 6774 int ret; 6775 6776 if (file->f_op == &bpf_map_fops) { 6777 map = file->private_data; 6778 bpfsec = map->security; 6779 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6780 bpf_map_fmode_to_av(file->f_mode), NULL); 6781 if (ret) 6782 return ret; 6783 } else if (file->f_op == &bpf_prog_fops) { 6784 prog = file->private_data; 6785 bpfsec = prog->aux->security; 6786 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6787 BPF__PROG_RUN, NULL); 6788 if (ret) 6789 return ret; 6790 } 6791 return 0; 6792 } 6793 6794 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6795 { 6796 u32 sid = current_sid(); 6797 struct bpf_security_struct *bpfsec; 6798 6799 bpfsec = map->security; 6800 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6801 bpf_map_fmode_to_av(fmode), NULL); 6802 } 6803 6804 static int selinux_bpf_prog(struct bpf_prog *prog) 6805 { 6806 u32 sid = current_sid(); 6807 struct bpf_security_struct *bpfsec; 6808 6809 bpfsec = prog->aux->security; 6810 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6811 BPF__PROG_RUN, NULL); 6812 } 6813 6814 static int selinux_bpf_map_alloc(struct bpf_map *map) 6815 { 6816 struct bpf_security_struct *bpfsec; 6817 6818 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6819 if (!bpfsec) 6820 return -ENOMEM; 6821 6822 bpfsec->sid = current_sid(); 6823 map->security = bpfsec; 6824 6825 return 0; 6826 } 6827 6828 static void selinux_bpf_map_free(struct bpf_map *map) 6829 { 6830 struct bpf_security_struct *bpfsec = map->security; 6831 6832 map->security = NULL; 6833 kfree(bpfsec); 6834 } 6835 6836 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6837 { 6838 struct bpf_security_struct *bpfsec; 6839 6840 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6841 if (!bpfsec) 6842 return -ENOMEM; 6843 6844 bpfsec->sid = current_sid(); 6845 aux->security = bpfsec; 6846 6847 return 0; 6848 } 6849 6850 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6851 { 6852 struct bpf_security_struct *bpfsec = aux->security; 6853 6854 aux->security = NULL; 6855 kfree(bpfsec); 6856 } 6857 #endif 6858 6859 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 6860 .lbs_cred = sizeof(struct task_security_struct), 6861 .lbs_file = sizeof(struct file_security_struct), 6862 .lbs_inode = sizeof(struct inode_security_struct), 6863 .lbs_ipc = sizeof(struct ipc_security_struct), 6864 .lbs_msg_msg = sizeof(struct msg_security_struct), 6865 .lbs_superblock = sizeof(struct superblock_security_struct), 6866 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 6867 }; 6868 6869 #ifdef CONFIG_PERF_EVENTS 6870 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6871 { 6872 u32 requested, sid = current_sid(); 6873 6874 if (type == PERF_SECURITY_OPEN) 6875 requested = PERF_EVENT__OPEN; 6876 else if (type == PERF_SECURITY_CPU) 6877 requested = PERF_EVENT__CPU; 6878 else if (type == PERF_SECURITY_KERNEL) 6879 requested = PERF_EVENT__KERNEL; 6880 else if (type == PERF_SECURITY_TRACEPOINT) 6881 requested = PERF_EVENT__TRACEPOINT; 6882 else 6883 return -EINVAL; 6884 6885 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 6886 requested, NULL); 6887 } 6888 6889 static int selinux_perf_event_alloc(struct perf_event *event) 6890 { 6891 struct perf_event_security_struct *perfsec; 6892 6893 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 6894 if (!perfsec) 6895 return -ENOMEM; 6896 6897 perfsec->sid = current_sid(); 6898 event->security = perfsec; 6899 6900 return 0; 6901 } 6902 6903 static void selinux_perf_event_free(struct perf_event *event) 6904 { 6905 struct perf_event_security_struct *perfsec = event->security; 6906 6907 event->security = NULL; 6908 kfree(perfsec); 6909 } 6910 6911 static int selinux_perf_event_read(struct perf_event *event) 6912 { 6913 struct perf_event_security_struct *perfsec = event->security; 6914 u32 sid = current_sid(); 6915 6916 return avc_has_perm(sid, perfsec->sid, 6917 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6918 } 6919 6920 static int selinux_perf_event_write(struct perf_event *event) 6921 { 6922 struct perf_event_security_struct *perfsec = event->security; 6923 u32 sid = current_sid(); 6924 6925 return avc_has_perm(sid, perfsec->sid, 6926 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 6927 } 6928 #endif 6929 6930 #ifdef CONFIG_IO_URING 6931 /** 6932 * selinux_uring_override_creds - check the requested cred override 6933 * @new: the target creds 6934 * 6935 * Check to see if the current task is allowed to override it's credentials 6936 * to service an io_uring operation. 6937 */ 6938 static int selinux_uring_override_creds(const struct cred *new) 6939 { 6940 return avc_has_perm(current_sid(), cred_sid(new), 6941 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 6942 } 6943 6944 /** 6945 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 6946 * 6947 * Check to see if the current task is allowed to create a new io_uring 6948 * kernel polling thread. 6949 */ 6950 static int selinux_uring_sqpoll(void) 6951 { 6952 u32 sid = current_sid(); 6953 6954 return avc_has_perm(sid, sid, 6955 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 6956 } 6957 6958 /** 6959 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 6960 * @ioucmd: the io_uring command structure 6961 * 6962 * Check to see if the current domain is allowed to execute an 6963 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 6964 * 6965 */ 6966 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 6967 { 6968 struct file *file = ioucmd->file; 6969 struct inode *inode = file_inode(file); 6970 struct inode_security_struct *isec = selinux_inode(inode); 6971 struct common_audit_data ad; 6972 6973 ad.type = LSM_AUDIT_DATA_FILE; 6974 ad.u.file = file; 6975 6976 return avc_has_perm(current_sid(), isec->sid, 6977 SECCLASS_IO_URING, IO_URING__CMD, &ad); 6978 } 6979 #endif /* CONFIG_IO_URING */ 6980 6981 /* 6982 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 6983 * 1. any hooks that don't belong to (2.) or (3.) below, 6984 * 2. hooks that both access structures allocated by other hooks, and allocate 6985 * structures that can be later accessed by other hooks (mostly "cloning" 6986 * hooks), 6987 * 3. hooks that only allocate structures that can be later accessed by other 6988 * hooks ("allocating" hooks). 6989 * 6990 * Please follow block comment delimiters in the list to keep this order. 6991 */ 6992 static struct security_hook_list selinux_hooks[] __ro_after_init = { 6993 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6994 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6995 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6996 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6997 6998 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6999 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 7000 LSM_HOOK_INIT(capget, selinux_capget), 7001 LSM_HOOK_INIT(capset, selinux_capset), 7002 LSM_HOOK_INIT(capable, selinux_capable), 7003 LSM_HOOK_INIT(quotactl, selinux_quotactl), 7004 LSM_HOOK_INIT(quota_on, selinux_quota_on), 7005 LSM_HOOK_INIT(syslog, selinux_syslog), 7006 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 7007 7008 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 7009 7010 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 7011 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 7012 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 7013 7014 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 7015 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 7016 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 7017 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 7018 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 7019 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 7020 LSM_HOOK_INIT(sb_mount, selinux_mount), 7021 LSM_HOOK_INIT(sb_umount, selinux_umount), 7022 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7023 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7024 7025 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7026 7027 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7028 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7029 7030 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7031 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7032 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7033 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7034 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7035 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7036 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7037 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7038 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7039 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7040 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7041 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7042 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7043 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7044 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7045 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7046 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7047 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7048 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7049 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7050 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7051 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7052 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7053 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7054 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7055 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7056 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7057 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7058 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7059 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7060 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7061 7062 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7063 7064 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7065 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7066 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7067 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat), 7068 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7069 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7070 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7071 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7072 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7073 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7074 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7075 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7076 7077 LSM_HOOK_INIT(file_open, selinux_file_open), 7078 7079 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7080 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7081 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7082 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7083 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7084 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7085 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7086 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7087 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7088 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7089 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7090 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7091 LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), 7092 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), 7093 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7094 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7095 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7096 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7097 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7098 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7099 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7100 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7101 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7102 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7103 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7104 7105 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7106 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7107 7108 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7109 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7110 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7111 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7112 7113 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7114 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7115 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7116 7117 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7118 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7119 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7120 7121 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7122 7123 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7124 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7125 7126 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7127 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7128 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7129 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7130 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7131 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7132 7133 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7134 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7135 7136 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7137 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7138 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7139 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7140 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7141 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7142 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7143 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7144 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7145 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7146 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7147 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7148 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7149 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7150 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7151 LSM_HOOK_INIT(socket_getpeersec_stream, 7152 selinux_socket_getpeersec_stream), 7153 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7154 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7155 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7156 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7157 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7158 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7159 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7160 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7161 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7162 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7163 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7164 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7165 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7166 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7167 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7168 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7169 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7170 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7171 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7172 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7173 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7174 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7175 #ifdef CONFIG_SECURITY_INFINIBAND 7176 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7177 LSM_HOOK_INIT(ib_endport_manage_subnet, 7178 selinux_ib_endport_manage_subnet), 7179 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7180 #endif 7181 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7182 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7183 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7184 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7185 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7186 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7187 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7188 selinux_xfrm_state_pol_flow_match), 7189 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7190 #endif 7191 7192 #ifdef CONFIG_KEYS 7193 LSM_HOOK_INIT(key_free, selinux_key_free), 7194 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7195 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7196 #ifdef CONFIG_KEY_NOTIFICATIONS 7197 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7198 #endif 7199 #endif 7200 7201 #ifdef CONFIG_AUDIT 7202 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7203 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7204 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7205 #endif 7206 7207 #ifdef CONFIG_BPF_SYSCALL 7208 LSM_HOOK_INIT(bpf, selinux_bpf), 7209 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7210 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7211 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7212 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7213 #endif 7214 7215 #ifdef CONFIG_PERF_EVENTS 7216 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7217 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7218 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7219 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7220 #endif 7221 7222 #ifdef CONFIG_IO_URING 7223 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7224 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7225 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7226 #endif 7227 7228 /* 7229 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7230 */ 7231 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7232 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7233 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7234 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7235 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7236 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7237 #endif 7238 7239 /* 7240 * PUT "ALLOCATING" HOOKS HERE 7241 */ 7242 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7243 LSM_HOOK_INIT(msg_queue_alloc_security, 7244 selinux_msg_queue_alloc_security), 7245 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7246 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7247 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7248 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7249 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7250 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7251 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7252 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7253 #ifdef CONFIG_SECURITY_INFINIBAND 7254 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7255 #endif 7256 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7257 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7258 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7259 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7260 selinux_xfrm_state_alloc_acquire), 7261 #endif 7262 #ifdef CONFIG_KEYS 7263 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7264 #endif 7265 #ifdef CONFIG_AUDIT 7266 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7267 #endif 7268 #ifdef CONFIG_BPF_SYSCALL 7269 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7270 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7271 #endif 7272 #ifdef CONFIG_PERF_EVENTS 7273 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7274 #endif 7275 }; 7276 7277 static __init int selinux_init(void) 7278 { 7279 pr_info("SELinux: Initializing.\n"); 7280 7281 memset(&selinux_state, 0, sizeof(selinux_state)); 7282 enforcing_set(selinux_enforcing_boot); 7283 selinux_avc_init(); 7284 mutex_init(&selinux_state.status_lock); 7285 mutex_init(&selinux_state.policy_mutex); 7286 7287 /* Set the security state for the initial task. */ 7288 cred_init_security(); 7289 7290 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7291 if (!default_noexec) 7292 pr_notice("SELinux: virtual memory is executable by default\n"); 7293 7294 avc_init(); 7295 7296 avtab_cache_init(); 7297 7298 ebitmap_cache_init(); 7299 7300 hashtab_cache_init(); 7301 7302 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7303 7304 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7305 panic("SELinux: Unable to register AVC netcache callback\n"); 7306 7307 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7308 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7309 7310 if (selinux_enforcing_boot) 7311 pr_debug("SELinux: Starting in enforcing mode\n"); 7312 else 7313 pr_debug("SELinux: Starting in permissive mode\n"); 7314 7315 fs_validate_description("selinux", selinux_fs_parameters); 7316 7317 return 0; 7318 } 7319 7320 static void delayed_superblock_init(struct super_block *sb, void *unused) 7321 { 7322 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7323 } 7324 7325 void selinux_complete_init(void) 7326 { 7327 pr_debug("SELinux: Completing initialization.\n"); 7328 7329 /* Set up any superblocks initialized prior to the policy load. */ 7330 pr_debug("SELinux: Setting up existing superblocks.\n"); 7331 iterate_supers(delayed_superblock_init, NULL); 7332 } 7333 7334 /* SELinux requires early initialization in order to label 7335 all processes and objects when they are created. */ 7336 DEFINE_LSM(selinux) = { 7337 .name = "selinux", 7338 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7339 .enabled = &selinux_enabled_boot, 7340 .blobs = &selinux_blob_sizes, 7341 .init = selinux_init, 7342 }; 7343 7344 #if defined(CONFIG_NETFILTER) 7345 static const struct nf_hook_ops selinux_nf_ops[] = { 7346 { 7347 .hook = selinux_ip_postroute, 7348 .pf = NFPROTO_IPV4, 7349 .hooknum = NF_INET_POST_ROUTING, 7350 .priority = NF_IP_PRI_SELINUX_LAST, 7351 }, 7352 { 7353 .hook = selinux_ip_forward, 7354 .pf = NFPROTO_IPV4, 7355 .hooknum = NF_INET_FORWARD, 7356 .priority = NF_IP_PRI_SELINUX_FIRST, 7357 }, 7358 { 7359 .hook = selinux_ip_output, 7360 .pf = NFPROTO_IPV4, 7361 .hooknum = NF_INET_LOCAL_OUT, 7362 .priority = NF_IP_PRI_SELINUX_FIRST, 7363 }, 7364 #if IS_ENABLED(CONFIG_IPV6) 7365 { 7366 .hook = selinux_ip_postroute, 7367 .pf = NFPROTO_IPV6, 7368 .hooknum = NF_INET_POST_ROUTING, 7369 .priority = NF_IP6_PRI_SELINUX_LAST, 7370 }, 7371 { 7372 .hook = selinux_ip_forward, 7373 .pf = NFPROTO_IPV6, 7374 .hooknum = NF_INET_FORWARD, 7375 .priority = NF_IP6_PRI_SELINUX_FIRST, 7376 }, 7377 { 7378 .hook = selinux_ip_output, 7379 .pf = NFPROTO_IPV6, 7380 .hooknum = NF_INET_LOCAL_OUT, 7381 .priority = NF_IP6_PRI_SELINUX_FIRST, 7382 }, 7383 #endif /* IPV6 */ 7384 }; 7385 7386 static int __net_init selinux_nf_register(struct net *net) 7387 { 7388 return nf_register_net_hooks(net, selinux_nf_ops, 7389 ARRAY_SIZE(selinux_nf_ops)); 7390 } 7391 7392 static void __net_exit selinux_nf_unregister(struct net *net) 7393 { 7394 nf_unregister_net_hooks(net, selinux_nf_ops, 7395 ARRAY_SIZE(selinux_nf_ops)); 7396 } 7397 7398 static struct pernet_operations selinux_net_ops = { 7399 .init = selinux_nf_register, 7400 .exit = selinux_nf_unregister, 7401 }; 7402 7403 static int __init selinux_nf_ip_init(void) 7404 { 7405 int err; 7406 7407 if (!selinux_enabled_boot) 7408 return 0; 7409 7410 pr_debug("SELinux: Registering netfilter hooks\n"); 7411 7412 err = register_pernet_subsys(&selinux_net_ops); 7413 if (err) 7414 panic("SELinux: register_pernet_subsys: error %d\n", err); 7415 7416 return 0; 7417 } 7418 __initcall(selinux_nf_ip_init); 7419 #endif /* CONFIG_NETFILTER */ 7420