1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Security-Enhanced Linux (SELinux) security module 4 * 5 * This file contains the SELinux hook function implementations. 6 * 7 * Authors: Stephen Smalley, <stephen.smalley.work@gmail.com> 8 * Chris Vance, <cvance@nai.com> 9 * Wayne Salamon, <wsalamon@nai.com> 10 * James Morris <jmorris@redhat.com> 11 * 12 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 13 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> 14 * Eric Paris <eparis@redhat.com> 15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 16 * <dgoeddel@trustedcs.com> 17 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. 18 * Paul Moore <paul@paul-moore.com> 19 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 20 * Yuichi Nakamura <ynakam@hitachisoft.jp> 21 * Copyright (C) 2016 Mellanox Technologies 22 */ 23 24 #include <linux/init.h> 25 #include <linux/kd.h> 26 #include <linux/kernel.h> 27 #include <linux/kernel_read_file.h> 28 #include <linux/errno.h> 29 #include <linux/sched/signal.h> 30 #include <linux/sched/task.h> 31 #include <linux/lsm_hooks.h> 32 #include <linux/xattr.h> 33 #include <linux/capability.h> 34 #include <linux/unistd.h> 35 #include <linux/mm.h> 36 #include <linux/mman.h> 37 #include <linux/slab.h> 38 #include <linux/pagemap.h> 39 #include <linux/proc_fs.h> 40 #include <linux/swap.h> 41 #include <linux/spinlock.h> 42 #include <linux/syscalls.h> 43 #include <linux/dcache.h> 44 #include <linux/file.h> 45 #include <linux/fdtable.h> 46 #include <linux/namei.h> 47 #include <linux/mount.h> 48 #include <linux/fs_context.h> 49 #include <linux/fs_parser.h> 50 #include <linux/netfilter_ipv4.h> 51 #include <linux/netfilter_ipv6.h> 52 #include <linux/tty.h> 53 #include <net/icmp.h> 54 #include <net/ip.h> /* for local_port_range[] */ 55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 56 #include <net/inet_connection_sock.h> 57 #include <net/net_namespace.h> 58 #include <net/netlabel.h> 59 #include <linux/uaccess.h> 60 #include <asm/ioctls.h> 61 #include <linux/atomic.h> 62 #include <linux/bitops.h> 63 #include <linux/interrupt.h> 64 #include <linux/netdevice.h> /* for network interface checks */ 65 #include <net/netlink.h> 66 #include <linux/tcp.h> 67 #include <linux/udp.h> 68 #include <linux/dccp.h> 69 #include <linux/sctp.h> 70 #include <net/sctp/structs.h> 71 #include <linux/quota.h> 72 #include <linux/un.h> /* for Unix socket types */ 73 #include <net/af_unix.h> /* for Unix socket types */ 74 #include <linux/parser.h> 75 #include <linux/nfs_mount.h> 76 #include <net/ipv6.h> 77 #include <linux/hugetlb.h> 78 #include <linux/personality.h> 79 #include <linux/audit.h> 80 #include <linux/string.h> 81 #include <linux/mutex.h> 82 #include <linux/posix-timers.h> 83 #include <linux/syslog.h> 84 #include <linux/user_namespace.h> 85 #include <linux/export.h> 86 #include <linux/msg.h> 87 #include <linux/shm.h> 88 #include <uapi/linux/shm.h> 89 #include <linux/bpf.h> 90 #include <linux/kernfs.h> 91 #include <linux/stringhash.h> /* for hashlen_string() */ 92 #include <uapi/linux/mount.h> 93 #include <linux/fsnotify.h> 94 #include <linux/fanotify.h> 95 #include <linux/io_uring/cmd.h> 96 #include <uapi/linux/lsm.h> 97 98 #include "avc.h" 99 #include "objsec.h" 100 #include "netif.h" 101 #include "netnode.h" 102 #include "netport.h" 103 #include "ibpkey.h" 104 #include "xfrm.h" 105 #include "netlabel.h" 106 #include "audit.h" 107 #include "avc_ss.h" 108 109 #define SELINUX_INODE_INIT_XATTRS 1 110 111 struct selinux_state selinux_state; 112 113 /* SECMARK reference count */ 114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 115 116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 117 static int selinux_enforcing_boot __initdata; 118 119 static int __init enforcing_setup(char *str) 120 { 121 unsigned long enforcing; 122 if (!kstrtoul(str, 0, &enforcing)) 123 selinux_enforcing_boot = enforcing ? 1 : 0; 124 return 1; 125 } 126 __setup("enforcing=", enforcing_setup); 127 #else 128 #define selinux_enforcing_boot 1 129 #endif 130 131 int selinux_enabled_boot __initdata = 1; 132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 133 static int __init selinux_enabled_setup(char *str) 134 { 135 unsigned long enabled; 136 if (!kstrtoul(str, 0, &enabled)) 137 selinux_enabled_boot = enabled ? 1 : 0; 138 return 1; 139 } 140 __setup("selinux=", selinux_enabled_setup); 141 #endif 142 143 static int __init checkreqprot_setup(char *str) 144 { 145 unsigned long checkreqprot; 146 147 if (!kstrtoul(str, 0, &checkreqprot)) { 148 if (checkreqprot) 149 pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n"); 150 } 151 return 1; 152 } 153 __setup("checkreqprot=", checkreqprot_setup); 154 155 /** 156 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 157 * 158 * Description: 159 * This function checks the SECMARK reference counter to see if any SECMARK 160 * targets are currently configured, if the reference counter is greater than 161 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 162 * enabled, false (0) if SECMARK is disabled. If the always_check_network 163 * policy capability is enabled, SECMARK is always considered enabled. 164 * 165 */ 166 static int selinux_secmark_enabled(void) 167 { 168 return (selinux_policycap_alwaysnetwork() || 169 atomic_read(&selinux_secmark_refcount)); 170 } 171 172 /** 173 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 174 * 175 * Description: 176 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 177 * (1) if any are enabled or false (0) if neither are enabled. If the 178 * always_check_network policy capability is enabled, peer labeling 179 * is always considered enabled. 180 * 181 */ 182 static int selinux_peerlbl_enabled(void) 183 { 184 return (selinux_policycap_alwaysnetwork() || 185 netlbl_enabled() || selinux_xfrm_enabled()); 186 } 187 188 static int selinux_netcache_avc_callback(u32 event) 189 { 190 if (event == AVC_CALLBACK_RESET) { 191 sel_netif_flush(); 192 sel_netnode_flush(); 193 sel_netport_flush(); 194 synchronize_net(); 195 } 196 return 0; 197 } 198 199 static int selinux_lsm_notifier_avc_callback(u32 event) 200 { 201 if (event == AVC_CALLBACK_RESET) { 202 sel_ib_pkey_flush(); 203 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); 204 } 205 206 return 0; 207 } 208 209 /* 210 * initialise the security for the init task 211 */ 212 static void cred_init_security(void) 213 { 214 struct task_security_struct *tsec; 215 216 tsec = selinux_cred(unrcu_pointer(current->real_cred)); 217 tsec->osid = tsec->sid = SECINITSID_KERNEL; 218 } 219 220 /* 221 * get the security ID of a set of credentials 222 */ 223 static inline u32 cred_sid(const struct cred *cred) 224 { 225 const struct task_security_struct *tsec; 226 227 tsec = selinux_cred(cred); 228 return tsec->sid; 229 } 230 231 static void __ad_net_init(struct common_audit_data *ad, 232 struct lsm_network_audit *net, 233 int ifindex, struct sock *sk, u16 family) 234 { 235 ad->type = LSM_AUDIT_DATA_NET; 236 ad->u.net = net; 237 net->netif = ifindex; 238 net->sk = sk; 239 net->family = family; 240 } 241 242 static void ad_net_init_from_sk(struct common_audit_data *ad, 243 struct lsm_network_audit *net, 244 struct sock *sk) 245 { 246 __ad_net_init(ad, net, 0, sk, 0); 247 } 248 249 static void ad_net_init_from_iif(struct common_audit_data *ad, 250 struct lsm_network_audit *net, 251 int ifindex, u16 family) 252 { 253 __ad_net_init(ad, net, ifindex, NULL, family); 254 } 255 256 /* 257 * get the objective security ID of a task 258 */ 259 static inline u32 task_sid_obj(const struct task_struct *task) 260 { 261 u32 sid; 262 263 rcu_read_lock(); 264 sid = cred_sid(__task_cred(task)); 265 rcu_read_unlock(); 266 return sid; 267 } 268 269 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 270 271 /* 272 * Try reloading inode security labels that have been marked as invalid. The 273 * @may_sleep parameter indicates when sleeping and thus reloading labels is 274 * allowed; when set to false, returns -ECHILD when the label is 275 * invalid. The @dentry parameter should be set to a dentry of the inode. 276 */ 277 static int __inode_security_revalidate(struct inode *inode, 278 struct dentry *dentry, 279 bool may_sleep) 280 { 281 struct inode_security_struct *isec = selinux_inode(inode); 282 283 might_sleep_if(may_sleep); 284 285 if (selinux_initialized() && 286 isec->initialized != LABEL_INITIALIZED) { 287 if (!may_sleep) 288 return -ECHILD; 289 290 /* 291 * Try reloading the inode security label. This will fail if 292 * @opt_dentry is NULL and no dentry for this inode can be 293 * found; in that case, continue using the old label. 294 */ 295 inode_doinit_with_dentry(inode, dentry); 296 } 297 return 0; 298 } 299 300 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 301 { 302 return selinux_inode(inode); 303 } 304 305 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 306 { 307 int error; 308 309 error = __inode_security_revalidate(inode, NULL, !rcu); 310 if (error) 311 return ERR_PTR(error); 312 return selinux_inode(inode); 313 } 314 315 /* 316 * Get the security label of an inode. 317 */ 318 static struct inode_security_struct *inode_security(struct inode *inode) 319 { 320 __inode_security_revalidate(inode, NULL, true); 321 return selinux_inode(inode); 322 } 323 324 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 325 { 326 struct inode *inode = d_backing_inode(dentry); 327 328 return selinux_inode(inode); 329 } 330 331 /* 332 * Get the security label of a dentry's backing inode. 333 */ 334 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 335 { 336 struct inode *inode = d_backing_inode(dentry); 337 338 __inode_security_revalidate(inode, dentry, true); 339 return selinux_inode(inode); 340 } 341 342 static void inode_free_security(struct inode *inode) 343 { 344 struct inode_security_struct *isec = selinux_inode(inode); 345 struct superblock_security_struct *sbsec; 346 347 if (!isec) 348 return; 349 sbsec = selinux_superblock(inode->i_sb); 350 /* 351 * As not all inode security structures are in a list, we check for 352 * empty list outside of the lock to make sure that we won't waste 353 * time taking a lock doing nothing. 354 * 355 * The list_del_init() function can be safely called more than once. 356 * It should not be possible for this function to be called with 357 * concurrent list_add(), but for better safety against future changes 358 * in the code, we use list_empty_careful() here. 359 */ 360 if (!list_empty_careful(&isec->list)) { 361 spin_lock(&sbsec->isec_lock); 362 list_del_init(&isec->list); 363 spin_unlock(&sbsec->isec_lock); 364 } 365 } 366 367 struct selinux_mnt_opts { 368 u32 fscontext_sid; 369 u32 context_sid; 370 u32 rootcontext_sid; 371 u32 defcontext_sid; 372 }; 373 374 static void selinux_free_mnt_opts(void *mnt_opts) 375 { 376 kfree(mnt_opts); 377 } 378 379 enum { 380 Opt_error = -1, 381 Opt_context = 0, 382 Opt_defcontext = 1, 383 Opt_fscontext = 2, 384 Opt_rootcontext = 3, 385 Opt_seclabel = 4, 386 }; 387 388 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 389 static const struct { 390 const char *name; 391 int len; 392 int opt; 393 bool has_arg; 394 } tokens[] = { 395 A(context, true), 396 A(fscontext, true), 397 A(defcontext, true), 398 A(rootcontext, true), 399 A(seclabel, false), 400 }; 401 #undef A 402 403 static int match_opt_prefix(char *s, int l, char **arg) 404 { 405 int i; 406 407 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 408 size_t len = tokens[i].len; 409 if (len > l || memcmp(s, tokens[i].name, len)) 410 continue; 411 if (tokens[i].has_arg) { 412 if (len == l || s[len] != '=') 413 continue; 414 *arg = s + len + 1; 415 } else if (len != l) 416 continue; 417 return tokens[i].opt; 418 } 419 return Opt_error; 420 } 421 422 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 423 424 static int may_context_mount_sb_relabel(u32 sid, 425 struct superblock_security_struct *sbsec, 426 const struct cred *cred) 427 { 428 const struct task_security_struct *tsec = selinux_cred(cred); 429 int rc; 430 431 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 432 FILESYSTEM__RELABELFROM, NULL); 433 if (rc) 434 return rc; 435 436 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 437 FILESYSTEM__RELABELTO, NULL); 438 return rc; 439 } 440 441 static int may_context_mount_inode_relabel(u32 sid, 442 struct superblock_security_struct *sbsec, 443 const struct cred *cred) 444 { 445 const struct task_security_struct *tsec = selinux_cred(cred); 446 int rc; 447 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 448 FILESYSTEM__RELABELFROM, NULL); 449 if (rc) 450 return rc; 451 452 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 453 FILESYSTEM__ASSOCIATE, NULL); 454 return rc; 455 } 456 457 static int selinux_is_genfs_special_handling(struct super_block *sb) 458 { 459 /* Special handling. Genfs but also in-core setxattr handler */ 460 return !strcmp(sb->s_type->name, "sysfs") || 461 !strcmp(sb->s_type->name, "pstore") || 462 !strcmp(sb->s_type->name, "debugfs") || 463 !strcmp(sb->s_type->name, "tracefs") || 464 !strcmp(sb->s_type->name, "rootfs") || 465 (selinux_policycap_cgroupseclabel() && 466 (!strcmp(sb->s_type->name, "cgroup") || 467 !strcmp(sb->s_type->name, "cgroup2"))); 468 } 469 470 static int selinux_is_sblabel_mnt(struct super_block *sb) 471 { 472 struct superblock_security_struct *sbsec = selinux_superblock(sb); 473 474 /* 475 * IMPORTANT: Double-check logic in this function when adding a new 476 * SECURITY_FS_USE_* definition! 477 */ 478 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 479 480 switch (sbsec->behavior) { 481 case SECURITY_FS_USE_XATTR: 482 case SECURITY_FS_USE_TRANS: 483 case SECURITY_FS_USE_TASK: 484 case SECURITY_FS_USE_NATIVE: 485 return 1; 486 487 case SECURITY_FS_USE_GENFS: 488 return selinux_is_genfs_special_handling(sb); 489 490 /* Never allow relabeling on context mounts */ 491 case SECURITY_FS_USE_MNTPOINT: 492 case SECURITY_FS_USE_NONE: 493 default: 494 return 0; 495 } 496 } 497 498 static int sb_check_xattr_support(struct super_block *sb) 499 { 500 struct superblock_security_struct *sbsec = selinux_superblock(sb); 501 struct dentry *root = sb->s_root; 502 struct inode *root_inode = d_backing_inode(root); 503 u32 sid; 504 int rc; 505 506 /* 507 * Make sure that the xattr handler exists and that no 508 * error other than -ENODATA is returned by getxattr on 509 * the root directory. -ENODATA is ok, as this may be 510 * the first boot of the SELinux kernel before we have 511 * assigned xattr values to the filesystem. 512 */ 513 if (!(root_inode->i_opflags & IOP_XATTR)) { 514 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", 515 sb->s_id, sb->s_type->name); 516 goto fallback; 517 } 518 519 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 520 if (rc < 0 && rc != -ENODATA) { 521 if (rc == -EOPNOTSUPP) { 522 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", 523 sb->s_id, sb->s_type->name); 524 goto fallback; 525 } else { 526 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", 527 sb->s_id, sb->s_type->name, -rc); 528 return rc; 529 } 530 } 531 return 0; 532 533 fallback: 534 /* No xattr support - try to fallback to genfs if possible. */ 535 rc = security_genfs_sid(sb->s_type->name, "/", 536 SECCLASS_DIR, &sid); 537 if (rc) 538 return -EOPNOTSUPP; 539 540 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", 541 sb->s_id, sb->s_type->name); 542 sbsec->behavior = SECURITY_FS_USE_GENFS; 543 sbsec->sid = sid; 544 return 0; 545 } 546 547 static int sb_finish_set_opts(struct super_block *sb) 548 { 549 struct superblock_security_struct *sbsec = selinux_superblock(sb); 550 struct dentry *root = sb->s_root; 551 struct inode *root_inode = d_backing_inode(root); 552 int rc = 0; 553 554 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 555 rc = sb_check_xattr_support(sb); 556 if (rc) 557 return rc; 558 } 559 560 sbsec->flags |= SE_SBINITIALIZED; 561 562 /* 563 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 564 * leave the flag untouched because sb_clone_mnt_opts might be handing 565 * us a superblock that needs the flag to be cleared. 566 */ 567 if (selinux_is_sblabel_mnt(sb)) 568 sbsec->flags |= SBLABEL_MNT; 569 else 570 sbsec->flags &= ~SBLABEL_MNT; 571 572 /* Initialize the root inode. */ 573 rc = inode_doinit_with_dentry(root_inode, root); 574 575 /* Initialize any other inodes associated with the superblock, e.g. 576 inodes created prior to initial policy load or inodes created 577 during get_sb by a pseudo filesystem that directly 578 populates itself. */ 579 spin_lock(&sbsec->isec_lock); 580 while (!list_empty(&sbsec->isec_head)) { 581 struct inode_security_struct *isec = 582 list_first_entry(&sbsec->isec_head, 583 struct inode_security_struct, list); 584 struct inode *inode = isec->inode; 585 list_del_init(&isec->list); 586 spin_unlock(&sbsec->isec_lock); 587 inode = igrab(inode); 588 if (inode) { 589 if (!IS_PRIVATE(inode)) 590 inode_doinit_with_dentry(inode, NULL); 591 iput(inode); 592 } 593 spin_lock(&sbsec->isec_lock); 594 } 595 spin_unlock(&sbsec->isec_lock); 596 return rc; 597 } 598 599 static int bad_option(struct superblock_security_struct *sbsec, char flag, 600 u32 old_sid, u32 new_sid) 601 { 602 char mnt_flags = sbsec->flags & SE_MNTMASK; 603 604 /* check if the old mount command had the same options */ 605 if (sbsec->flags & SE_SBINITIALIZED) 606 if (!(sbsec->flags & flag) || 607 (old_sid != new_sid)) 608 return 1; 609 610 /* check if we were passed the same options twice, 611 * aka someone passed context=a,context=b 612 */ 613 if (!(sbsec->flags & SE_SBINITIALIZED)) 614 if (mnt_flags & flag) 615 return 1; 616 return 0; 617 } 618 619 /* 620 * Allow filesystems with binary mount data to explicitly set mount point 621 * labeling information. 622 */ 623 static int selinux_set_mnt_opts(struct super_block *sb, 624 void *mnt_opts, 625 unsigned long kern_flags, 626 unsigned long *set_kern_flags) 627 { 628 const struct cred *cred = current_cred(); 629 struct superblock_security_struct *sbsec = selinux_superblock(sb); 630 struct dentry *root = sb->s_root; 631 struct selinux_mnt_opts *opts = mnt_opts; 632 struct inode_security_struct *root_isec; 633 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 634 u32 defcontext_sid = 0; 635 int rc = 0; 636 637 /* 638 * Specifying internal flags without providing a place to 639 * place the results is not allowed 640 */ 641 if (kern_flags && !set_kern_flags) 642 return -EINVAL; 643 644 mutex_lock(&sbsec->lock); 645 646 if (!selinux_initialized()) { 647 if (!opts) { 648 /* Defer initialization until selinux_complete_init, 649 after the initial policy is loaded and the security 650 server is ready to handle calls. */ 651 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 652 sbsec->flags |= SE_SBNATIVE; 653 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 654 } 655 goto out; 656 } 657 rc = -EINVAL; 658 pr_warn("SELinux: Unable to set superblock options " 659 "before the security server is initialized\n"); 660 goto out; 661 } 662 663 /* 664 * Binary mount data FS will come through this function twice. Once 665 * from an explicit call and once from the generic calls from the vfs. 666 * Since the generic VFS calls will not contain any security mount data 667 * we need to skip the double mount verification. 668 * 669 * This does open a hole in which we will not notice if the first 670 * mount using this sb set explicit options and a second mount using 671 * this sb does not set any security options. (The first options 672 * will be used for both mounts) 673 */ 674 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 675 && !opts) 676 goto out; 677 678 root_isec = backing_inode_security_novalidate(root); 679 680 /* 681 * parse the mount options, check if they are valid sids. 682 * also check if someone is trying to mount the same sb more 683 * than once with different security options. 684 */ 685 if (opts) { 686 if (opts->fscontext_sid) { 687 fscontext_sid = opts->fscontext_sid; 688 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 689 fscontext_sid)) 690 goto out_double_mount; 691 sbsec->flags |= FSCONTEXT_MNT; 692 } 693 if (opts->context_sid) { 694 context_sid = opts->context_sid; 695 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 696 context_sid)) 697 goto out_double_mount; 698 sbsec->flags |= CONTEXT_MNT; 699 } 700 if (opts->rootcontext_sid) { 701 rootcontext_sid = opts->rootcontext_sid; 702 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 703 rootcontext_sid)) 704 goto out_double_mount; 705 sbsec->flags |= ROOTCONTEXT_MNT; 706 } 707 if (opts->defcontext_sid) { 708 defcontext_sid = opts->defcontext_sid; 709 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 710 defcontext_sid)) 711 goto out_double_mount; 712 sbsec->flags |= DEFCONTEXT_MNT; 713 } 714 } 715 716 if (sbsec->flags & SE_SBINITIALIZED) { 717 /* previously mounted with options, but not on this attempt? */ 718 if ((sbsec->flags & SE_MNTMASK) && !opts) 719 goto out_double_mount; 720 rc = 0; 721 goto out; 722 } 723 724 if (strcmp(sb->s_type->name, "proc") == 0) 725 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 726 727 if (!strcmp(sb->s_type->name, "debugfs") || 728 !strcmp(sb->s_type->name, "tracefs") || 729 !strcmp(sb->s_type->name, "binder") || 730 !strcmp(sb->s_type->name, "bpf") || 731 !strcmp(sb->s_type->name, "pstore") || 732 !strcmp(sb->s_type->name, "securityfs")) 733 sbsec->flags |= SE_SBGENFS; 734 735 if (!strcmp(sb->s_type->name, "sysfs") || 736 !strcmp(sb->s_type->name, "cgroup") || 737 !strcmp(sb->s_type->name, "cgroup2")) 738 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 739 740 if (!sbsec->behavior) { 741 /* 742 * Determine the labeling behavior to use for this 743 * filesystem type. 744 */ 745 rc = security_fs_use(sb); 746 if (rc) { 747 pr_warn("%s: security_fs_use(%s) returned %d\n", 748 __func__, sb->s_type->name, rc); 749 goto out; 750 } 751 } 752 753 /* 754 * If this is a user namespace mount and the filesystem type is not 755 * explicitly whitelisted, then no contexts are allowed on the command 756 * line and security labels must be ignored. 757 */ 758 if (sb->s_user_ns != &init_user_ns && 759 strcmp(sb->s_type->name, "tmpfs") && 760 strcmp(sb->s_type->name, "ramfs") && 761 strcmp(sb->s_type->name, "devpts") && 762 strcmp(sb->s_type->name, "overlay")) { 763 if (context_sid || fscontext_sid || rootcontext_sid || 764 defcontext_sid) { 765 rc = -EACCES; 766 goto out; 767 } 768 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 769 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 770 rc = security_transition_sid(current_sid(), 771 current_sid(), 772 SECCLASS_FILE, NULL, 773 &sbsec->mntpoint_sid); 774 if (rc) 775 goto out; 776 } 777 goto out_set_opts; 778 } 779 780 /* sets the context of the superblock for the fs being mounted. */ 781 if (fscontext_sid) { 782 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 783 if (rc) 784 goto out; 785 786 sbsec->sid = fscontext_sid; 787 } 788 789 /* 790 * Switch to using mount point labeling behavior. 791 * sets the label used on all file below the mountpoint, and will set 792 * the superblock context if not already set. 793 */ 794 if (sbsec->flags & SE_SBNATIVE) { 795 /* 796 * This means we are initializing a superblock that has been 797 * mounted before the SELinux was initialized and the 798 * filesystem requested native labeling. We had already 799 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags 800 * in the original mount attempt, so now we just need to set 801 * the SECURITY_FS_USE_NATIVE behavior. 802 */ 803 sbsec->behavior = SECURITY_FS_USE_NATIVE; 804 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 805 sbsec->behavior = SECURITY_FS_USE_NATIVE; 806 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 807 } 808 809 if (context_sid) { 810 if (!fscontext_sid) { 811 rc = may_context_mount_sb_relabel(context_sid, sbsec, 812 cred); 813 if (rc) 814 goto out; 815 sbsec->sid = context_sid; 816 } else { 817 rc = may_context_mount_inode_relabel(context_sid, sbsec, 818 cred); 819 if (rc) 820 goto out; 821 } 822 if (!rootcontext_sid) 823 rootcontext_sid = context_sid; 824 825 sbsec->mntpoint_sid = context_sid; 826 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 827 } 828 829 if (rootcontext_sid) { 830 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 831 cred); 832 if (rc) 833 goto out; 834 835 root_isec->sid = rootcontext_sid; 836 root_isec->initialized = LABEL_INITIALIZED; 837 } 838 839 if (defcontext_sid) { 840 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 841 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 842 rc = -EINVAL; 843 pr_warn("SELinux: defcontext option is " 844 "invalid for this filesystem type\n"); 845 goto out; 846 } 847 848 if (defcontext_sid != sbsec->def_sid) { 849 rc = may_context_mount_inode_relabel(defcontext_sid, 850 sbsec, cred); 851 if (rc) 852 goto out; 853 } 854 855 sbsec->def_sid = defcontext_sid; 856 } 857 858 out_set_opts: 859 rc = sb_finish_set_opts(sb); 860 out: 861 mutex_unlock(&sbsec->lock); 862 return rc; 863 out_double_mount: 864 rc = -EINVAL; 865 pr_warn("SELinux: mount invalid. Same superblock, different " 866 "security settings for (dev %s, type %s)\n", sb->s_id, 867 sb->s_type->name); 868 goto out; 869 } 870 871 static int selinux_cmp_sb_context(const struct super_block *oldsb, 872 const struct super_block *newsb) 873 { 874 struct superblock_security_struct *old = selinux_superblock(oldsb); 875 struct superblock_security_struct *new = selinux_superblock(newsb); 876 char oldflags = old->flags & SE_MNTMASK; 877 char newflags = new->flags & SE_MNTMASK; 878 879 if (oldflags != newflags) 880 goto mismatch; 881 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 882 goto mismatch; 883 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 884 goto mismatch; 885 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 886 goto mismatch; 887 if (oldflags & ROOTCONTEXT_MNT) { 888 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 889 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 890 if (oldroot->sid != newroot->sid) 891 goto mismatch; 892 } 893 return 0; 894 mismatch: 895 pr_warn("SELinux: mount invalid. Same superblock, " 896 "different security settings for (dev %s, " 897 "type %s)\n", newsb->s_id, newsb->s_type->name); 898 return -EBUSY; 899 } 900 901 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 902 struct super_block *newsb, 903 unsigned long kern_flags, 904 unsigned long *set_kern_flags) 905 { 906 int rc = 0; 907 const struct superblock_security_struct *oldsbsec = 908 selinux_superblock(oldsb); 909 struct superblock_security_struct *newsbsec = selinux_superblock(newsb); 910 911 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 912 int set_context = (oldsbsec->flags & CONTEXT_MNT); 913 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 914 915 /* 916 * Specifying internal flags without providing a place to 917 * place the results is not allowed. 918 */ 919 if (kern_flags && !set_kern_flags) 920 return -EINVAL; 921 922 mutex_lock(&newsbsec->lock); 923 924 /* 925 * if the parent was able to be mounted it clearly had no special lsm 926 * mount options. thus we can safely deal with this superblock later 927 */ 928 if (!selinux_initialized()) { 929 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 930 newsbsec->flags |= SE_SBNATIVE; 931 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 932 } 933 goto out; 934 } 935 936 /* how can we clone if the old one wasn't set up?? */ 937 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 938 939 /* if fs is reusing a sb, make sure that the contexts match */ 940 if (newsbsec->flags & SE_SBINITIALIZED) { 941 mutex_unlock(&newsbsec->lock); 942 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 943 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 944 return selinux_cmp_sb_context(oldsb, newsb); 945 } 946 947 newsbsec->flags = oldsbsec->flags; 948 949 newsbsec->sid = oldsbsec->sid; 950 newsbsec->def_sid = oldsbsec->def_sid; 951 newsbsec->behavior = oldsbsec->behavior; 952 953 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 954 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 955 rc = security_fs_use(newsb); 956 if (rc) 957 goto out; 958 } 959 960 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 961 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 962 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 963 } 964 965 if (set_context) { 966 u32 sid = oldsbsec->mntpoint_sid; 967 968 if (!set_fscontext) 969 newsbsec->sid = sid; 970 if (!set_rootcontext) { 971 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 972 newisec->sid = sid; 973 } 974 newsbsec->mntpoint_sid = sid; 975 } 976 if (set_rootcontext) { 977 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 978 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 979 980 newisec->sid = oldisec->sid; 981 } 982 983 sb_finish_set_opts(newsb); 984 out: 985 mutex_unlock(&newsbsec->lock); 986 return rc; 987 } 988 989 /* 990 * NOTE: the caller is responsible for freeing the memory even if on error. 991 */ 992 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 993 { 994 struct selinux_mnt_opts *opts = *mnt_opts; 995 u32 *dst_sid; 996 int rc; 997 998 if (token == Opt_seclabel) 999 /* eaten and completely ignored */ 1000 return 0; 1001 if (!s) 1002 return -EINVAL; 1003 1004 if (!selinux_initialized()) { 1005 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); 1006 return -EINVAL; 1007 } 1008 1009 if (!opts) { 1010 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 1011 if (!opts) 1012 return -ENOMEM; 1013 *mnt_opts = opts; 1014 } 1015 1016 switch (token) { 1017 case Opt_context: 1018 if (opts->context_sid || opts->defcontext_sid) 1019 goto err; 1020 dst_sid = &opts->context_sid; 1021 break; 1022 case Opt_fscontext: 1023 if (opts->fscontext_sid) 1024 goto err; 1025 dst_sid = &opts->fscontext_sid; 1026 break; 1027 case Opt_rootcontext: 1028 if (opts->rootcontext_sid) 1029 goto err; 1030 dst_sid = &opts->rootcontext_sid; 1031 break; 1032 case Opt_defcontext: 1033 if (opts->context_sid || opts->defcontext_sid) 1034 goto err; 1035 dst_sid = &opts->defcontext_sid; 1036 break; 1037 default: 1038 WARN_ON(1); 1039 return -EINVAL; 1040 } 1041 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); 1042 if (rc) 1043 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", 1044 s, rc); 1045 return rc; 1046 1047 err: 1048 pr_warn(SEL_MOUNT_FAIL_MSG); 1049 return -EINVAL; 1050 } 1051 1052 static int show_sid(struct seq_file *m, u32 sid) 1053 { 1054 char *context = NULL; 1055 u32 len; 1056 int rc; 1057 1058 rc = security_sid_to_context(sid, &context, &len); 1059 if (!rc) { 1060 bool has_comma = strchr(context, ','); 1061 1062 seq_putc(m, '='); 1063 if (has_comma) 1064 seq_putc(m, '\"'); 1065 seq_escape(m, context, "\"\n\\"); 1066 if (has_comma) 1067 seq_putc(m, '\"'); 1068 } 1069 kfree(context); 1070 return rc; 1071 } 1072 1073 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1074 { 1075 struct superblock_security_struct *sbsec = selinux_superblock(sb); 1076 int rc; 1077 1078 if (!(sbsec->flags & SE_SBINITIALIZED)) 1079 return 0; 1080 1081 if (!selinux_initialized()) 1082 return 0; 1083 1084 if (sbsec->flags & FSCONTEXT_MNT) { 1085 seq_putc(m, ','); 1086 seq_puts(m, FSCONTEXT_STR); 1087 rc = show_sid(m, sbsec->sid); 1088 if (rc) 1089 return rc; 1090 } 1091 if (sbsec->flags & CONTEXT_MNT) { 1092 seq_putc(m, ','); 1093 seq_puts(m, CONTEXT_STR); 1094 rc = show_sid(m, sbsec->mntpoint_sid); 1095 if (rc) 1096 return rc; 1097 } 1098 if (sbsec->flags & DEFCONTEXT_MNT) { 1099 seq_putc(m, ','); 1100 seq_puts(m, DEFCONTEXT_STR); 1101 rc = show_sid(m, sbsec->def_sid); 1102 if (rc) 1103 return rc; 1104 } 1105 if (sbsec->flags & ROOTCONTEXT_MNT) { 1106 struct dentry *root = sb->s_root; 1107 struct inode_security_struct *isec = backing_inode_security(root); 1108 seq_putc(m, ','); 1109 seq_puts(m, ROOTCONTEXT_STR); 1110 rc = show_sid(m, isec->sid); 1111 if (rc) 1112 return rc; 1113 } 1114 if (sbsec->flags & SBLABEL_MNT) { 1115 seq_putc(m, ','); 1116 seq_puts(m, SECLABEL_STR); 1117 } 1118 return 0; 1119 } 1120 1121 static inline u16 inode_mode_to_security_class(umode_t mode) 1122 { 1123 switch (mode & S_IFMT) { 1124 case S_IFSOCK: 1125 return SECCLASS_SOCK_FILE; 1126 case S_IFLNK: 1127 return SECCLASS_LNK_FILE; 1128 case S_IFREG: 1129 return SECCLASS_FILE; 1130 case S_IFBLK: 1131 return SECCLASS_BLK_FILE; 1132 case S_IFDIR: 1133 return SECCLASS_DIR; 1134 case S_IFCHR: 1135 return SECCLASS_CHR_FILE; 1136 case S_IFIFO: 1137 return SECCLASS_FIFO_FILE; 1138 1139 } 1140 1141 return SECCLASS_FILE; 1142 } 1143 1144 static inline int default_protocol_stream(int protocol) 1145 { 1146 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || 1147 protocol == IPPROTO_MPTCP); 1148 } 1149 1150 static inline int default_protocol_dgram(int protocol) 1151 { 1152 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1153 } 1154 1155 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1156 { 1157 bool extsockclass = selinux_policycap_extsockclass(); 1158 1159 switch (family) { 1160 case PF_UNIX: 1161 switch (type) { 1162 case SOCK_STREAM: 1163 case SOCK_SEQPACKET: 1164 return SECCLASS_UNIX_STREAM_SOCKET; 1165 case SOCK_DGRAM: 1166 case SOCK_RAW: 1167 return SECCLASS_UNIX_DGRAM_SOCKET; 1168 } 1169 break; 1170 case PF_INET: 1171 case PF_INET6: 1172 switch (type) { 1173 case SOCK_STREAM: 1174 case SOCK_SEQPACKET: 1175 if (default_protocol_stream(protocol)) 1176 return SECCLASS_TCP_SOCKET; 1177 else if (extsockclass && protocol == IPPROTO_SCTP) 1178 return SECCLASS_SCTP_SOCKET; 1179 else 1180 return SECCLASS_RAWIP_SOCKET; 1181 case SOCK_DGRAM: 1182 if (default_protocol_dgram(protocol)) 1183 return SECCLASS_UDP_SOCKET; 1184 else if (extsockclass && (protocol == IPPROTO_ICMP || 1185 protocol == IPPROTO_ICMPV6)) 1186 return SECCLASS_ICMP_SOCKET; 1187 else 1188 return SECCLASS_RAWIP_SOCKET; 1189 case SOCK_DCCP: 1190 return SECCLASS_DCCP_SOCKET; 1191 default: 1192 return SECCLASS_RAWIP_SOCKET; 1193 } 1194 break; 1195 case PF_NETLINK: 1196 switch (protocol) { 1197 case NETLINK_ROUTE: 1198 return SECCLASS_NETLINK_ROUTE_SOCKET; 1199 case NETLINK_SOCK_DIAG: 1200 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1201 case NETLINK_NFLOG: 1202 return SECCLASS_NETLINK_NFLOG_SOCKET; 1203 case NETLINK_XFRM: 1204 return SECCLASS_NETLINK_XFRM_SOCKET; 1205 case NETLINK_SELINUX: 1206 return SECCLASS_NETLINK_SELINUX_SOCKET; 1207 case NETLINK_ISCSI: 1208 return SECCLASS_NETLINK_ISCSI_SOCKET; 1209 case NETLINK_AUDIT: 1210 return SECCLASS_NETLINK_AUDIT_SOCKET; 1211 case NETLINK_FIB_LOOKUP: 1212 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1213 case NETLINK_CONNECTOR: 1214 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1215 case NETLINK_NETFILTER: 1216 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1217 case NETLINK_DNRTMSG: 1218 return SECCLASS_NETLINK_DNRT_SOCKET; 1219 case NETLINK_KOBJECT_UEVENT: 1220 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1221 case NETLINK_GENERIC: 1222 return SECCLASS_NETLINK_GENERIC_SOCKET; 1223 case NETLINK_SCSITRANSPORT: 1224 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1225 case NETLINK_RDMA: 1226 return SECCLASS_NETLINK_RDMA_SOCKET; 1227 case NETLINK_CRYPTO: 1228 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1229 default: 1230 return SECCLASS_NETLINK_SOCKET; 1231 } 1232 case PF_PACKET: 1233 return SECCLASS_PACKET_SOCKET; 1234 case PF_KEY: 1235 return SECCLASS_KEY_SOCKET; 1236 case PF_APPLETALK: 1237 return SECCLASS_APPLETALK_SOCKET; 1238 } 1239 1240 if (extsockclass) { 1241 switch (family) { 1242 case PF_AX25: 1243 return SECCLASS_AX25_SOCKET; 1244 case PF_IPX: 1245 return SECCLASS_IPX_SOCKET; 1246 case PF_NETROM: 1247 return SECCLASS_NETROM_SOCKET; 1248 case PF_ATMPVC: 1249 return SECCLASS_ATMPVC_SOCKET; 1250 case PF_X25: 1251 return SECCLASS_X25_SOCKET; 1252 case PF_ROSE: 1253 return SECCLASS_ROSE_SOCKET; 1254 case PF_DECnet: 1255 return SECCLASS_DECNET_SOCKET; 1256 case PF_ATMSVC: 1257 return SECCLASS_ATMSVC_SOCKET; 1258 case PF_RDS: 1259 return SECCLASS_RDS_SOCKET; 1260 case PF_IRDA: 1261 return SECCLASS_IRDA_SOCKET; 1262 case PF_PPPOX: 1263 return SECCLASS_PPPOX_SOCKET; 1264 case PF_LLC: 1265 return SECCLASS_LLC_SOCKET; 1266 case PF_CAN: 1267 return SECCLASS_CAN_SOCKET; 1268 case PF_TIPC: 1269 return SECCLASS_TIPC_SOCKET; 1270 case PF_BLUETOOTH: 1271 return SECCLASS_BLUETOOTH_SOCKET; 1272 case PF_IUCV: 1273 return SECCLASS_IUCV_SOCKET; 1274 case PF_RXRPC: 1275 return SECCLASS_RXRPC_SOCKET; 1276 case PF_ISDN: 1277 return SECCLASS_ISDN_SOCKET; 1278 case PF_PHONET: 1279 return SECCLASS_PHONET_SOCKET; 1280 case PF_IEEE802154: 1281 return SECCLASS_IEEE802154_SOCKET; 1282 case PF_CAIF: 1283 return SECCLASS_CAIF_SOCKET; 1284 case PF_ALG: 1285 return SECCLASS_ALG_SOCKET; 1286 case PF_NFC: 1287 return SECCLASS_NFC_SOCKET; 1288 case PF_VSOCK: 1289 return SECCLASS_VSOCK_SOCKET; 1290 case PF_KCM: 1291 return SECCLASS_KCM_SOCKET; 1292 case PF_QIPCRTR: 1293 return SECCLASS_QIPCRTR_SOCKET; 1294 case PF_SMC: 1295 return SECCLASS_SMC_SOCKET; 1296 case PF_XDP: 1297 return SECCLASS_XDP_SOCKET; 1298 case PF_MCTP: 1299 return SECCLASS_MCTP_SOCKET; 1300 #if PF_MAX > 46 1301 #error New address family defined, please update this function. 1302 #endif 1303 } 1304 } 1305 1306 return SECCLASS_SOCKET; 1307 } 1308 1309 static int selinux_genfs_get_sid(struct dentry *dentry, 1310 u16 tclass, 1311 u16 flags, 1312 u32 *sid) 1313 { 1314 int rc; 1315 struct super_block *sb = dentry->d_sb; 1316 char *buffer, *path; 1317 1318 buffer = (char *)__get_free_page(GFP_KERNEL); 1319 if (!buffer) 1320 return -ENOMEM; 1321 1322 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1323 if (IS_ERR(path)) 1324 rc = PTR_ERR(path); 1325 else { 1326 if (flags & SE_SBPROC) { 1327 /* each process gets a /proc/PID/ entry. Strip off the 1328 * PID part to get a valid selinux labeling. 1329 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1330 while (path[1] >= '0' && path[1] <= '9') { 1331 path[1] = '/'; 1332 path++; 1333 } 1334 } 1335 rc = security_genfs_sid(sb->s_type->name, 1336 path, tclass, sid); 1337 if (rc == -ENOENT) { 1338 /* No match in policy, mark as unlabeled. */ 1339 *sid = SECINITSID_UNLABELED; 1340 rc = 0; 1341 } 1342 } 1343 free_page((unsigned long)buffer); 1344 return rc; 1345 } 1346 1347 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1348 u32 def_sid, u32 *sid) 1349 { 1350 #define INITCONTEXTLEN 255 1351 char *context; 1352 unsigned int len; 1353 int rc; 1354 1355 len = INITCONTEXTLEN; 1356 context = kmalloc(len + 1, GFP_NOFS); 1357 if (!context) 1358 return -ENOMEM; 1359 1360 context[len] = '\0'; 1361 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1362 if (rc == -ERANGE) { 1363 kfree(context); 1364 1365 /* Need a larger buffer. Query for the right size. */ 1366 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1367 if (rc < 0) 1368 return rc; 1369 1370 len = rc; 1371 context = kmalloc(len + 1, GFP_NOFS); 1372 if (!context) 1373 return -ENOMEM; 1374 1375 context[len] = '\0'; 1376 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1377 context, len); 1378 } 1379 if (rc < 0) { 1380 kfree(context); 1381 if (rc != -ENODATA) { 1382 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1383 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1384 return rc; 1385 } 1386 *sid = def_sid; 1387 return 0; 1388 } 1389 1390 rc = security_context_to_sid_default(context, rc, sid, 1391 def_sid, GFP_NOFS); 1392 if (rc) { 1393 char *dev = inode->i_sb->s_id; 1394 unsigned long ino = inode->i_ino; 1395 1396 if (rc == -EINVAL) { 1397 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", 1398 ino, dev, context); 1399 } else { 1400 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1401 __func__, context, -rc, dev, ino); 1402 } 1403 } 1404 kfree(context); 1405 return 0; 1406 } 1407 1408 /* The inode's security attributes must be initialized before first use. */ 1409 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1410 { 1411 struct superblock_security_struct *sbsec = NULL; 1412 struct inode_security_struct *isec = selinux_inode(inode); 1413 u32 task_sid, sid = 0; 1414 u16 sclass; 1415 struct dentry *dentry; 1416 int rc = 0; 1417 1418 if (isec->initialized == LABEL_INITIALIZED) 1419 return 0; 1420 1421 spin_lock(&isec->lock); 1422 if (isec->initialized == LABEL_INITIALIZED) 1423 goto out_unlock; 1424 1425 if (isec->sclass == SECCLASS_FILE) 1426 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1427 1428 sbsec = selinux_superblock(inode->i_sb); 1429 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1430 /* Defer initialization until selinux_complete_init, 1431 after the initial policy is loaded and the security 1432 server is ready to handle calls. */ 1433 spin_lock(&sbsec->isec_lock); 1434 if (list_empty(&isec->list)) 1435 list_add(&isec->list, &sbsec->isec_head); 1436 spin_unlock(&sbsec->isec_lock); 1437 goto out_unlock; 1438 } 1439 1440 sclass = isec->sclass; 1441 task_sid = isec->task_sid; 1442 sid = isec->sid; 1443 isec->initialized = LABEL_PENDING; 1444 spin_unlock(&isec->lock); 1445 1446 switch (sbsec->behavior) { 1447 /* 1448 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels 1449 * via xattr when called from delayed_superblock_init(). 1450 */ 1451 case SECURITY_FS_USE_NATIVE: 1452 case SECURITY_FS_USE_XATTR: 1453 if (!(inode->i_opflags & IOP_XATTR)) { 1454 sid = sbsec->def_sid; 1455 break; 1456 } 1457 /* Need a dentry, since the xattr API requires one. 1458 Life would be simpler if we could just pass the inode. */ 1459 if (opt_dentry) { 1460 /* Called from d_instantiate or d_splice_alias. */ 1461 dentry = dget(opt_dentry); 1462 } else { 1463 /* 1464 * Called from selinux_complete_init, try to find a dentry. 1465 * Some filesystems really want a connected one, so try 1466 * that first. We could split SECURITY_FS_USE_XATTR in 1467 * two, depending upon that... 1468 */ 1469 dentry = d_find_alias(inode); 1470 if (!dentry) 1471 dentry = d_find_any_alias(inode); 1472 } 1473 if (!dentry) { 1474 /* 1475 * this is can be hit on boot when a file is accessed 1476 * before the policy is loaded. When we load policy we 1477 * may find inodes that have no dentry on the 1478 * sbsec->isec_head list. No reason to complain as these 1479 * will get fixed up the next time we go through 1480 * inode_doinit with a dentry, before these inodes could 1481 * be used again by userspace. 1482 */ 1483 goto out_invalid; 1484 } 1485 1486 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1487 &sid); 1488 dput(dentry); 1489 if (rc) 1490 goto out; 1491 break; 1492 case SECURITY_FS_USE_TASK: 1493 sid = task_sid; 1494 break; 1495 case SECURITY_FS_USE_TRANS: 1496 /* Default to the fs SID. */ 1497 sid = sbsec->sid; 1498 1499 /* Try to obtain a transition SID. */ 1500 rc = security_transition_sid(task_sid, sid, 1501 sclass, NULL, &sid); 1502 if (rc) 1503 goto out; 1504 break; 1505 case SECURITY_FS_USE_MNTPOINT: 1506 sid = sbsec->mntpoint_sid; 1507 break; 1508 default: 1509 /* Default to the fs superblock SID. */ 1510 sid = sbsec->sid; 1511 1512 if ((sbsec->flags & SE_SBGENFS) && 1513 (!S_ISLNK(inode->i_mode) || 1514 selinux_policycap_genfs_seclabel_symlinks())) { 1515 /* We must have a dentry to determine the label on 1516 * procfs inodes */ 1517 if (opt_dentry) { 1518 /* Called from d_instantiate or 1519 * d_splice_alias. */ 1520 dentry = dget(opt_dentry); 1521 } else { 1522 /* Called from selinux_complete_init, try to 1523 * find a dentry. Some filesystems really want 1524 * a connected one, so try that first. 1525 */ 1526 dentry = d_find_alias(inode); 1527 if (!dentry) 1528 dentry = d_find_any_alias(inode); 1529 } 1530 /* 1531 * This can be hit on boot when a file is accessed 1532 * before the policy is loaded. When we load policy we 1533 * may find inodes that have no dentry on the 1534 * sbsec->isec_head list. No reason to complain as 1535 * these will get fixed up the next time we go through 1536 * inode_doinit() with a dentry, before these inodes 1537 * could be used again by userspace. 1538 */ 1539 if (!dentry) 1540 goto out_invalid; 1541 rc = selinux_genfs_get_sid(dentry, sclass, 1542 sbsec->flags, &sid); 1543 if (rc) { 1544 dput(dentry); 1545 goto out; 1546 } 1547 1548 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1549 (inode->i_opflags & IOP_XATTR)) { 1550 rc = inode_doinit_use_xattr(inode, dentry, 1551 sid, &sid); 1552 if (rc) { 1553 dput(dentry); 1554 goto out; 1555 } 1556 } 1557 dput(dentry); 1558 } 1559 break; 1560 } 1561 1562 out: 1563 spin_lock(&isec->lock); 1564 if (isec->initialized == LABEL_PENDING) { 1565 if (rc) { 1566 isec->initialized = LABEL_INVALID; 1567 goto out_unlock; 1568 } 1569 isec->initialized = LABEL_INITIALIZED; 1570 isec->sid = sid; 1571 } 1572 1573 out_unlock: 1574 spin_unlock(&isec->lock); 1575 return rc; 1576 1577 out_invalid: 1578 spin_lock(&isec->lock); 1579 if (isec->initialized == LABEL_PENDING) { 1580 isec->initialized = LABEL_INVALID; 1581 isec->sid = sid; 1582 } 1583 spin_unlock(&isec->lock); 1584 return 0; 1585 } 1586 1587 /* Convert a Linux signal to an access vector. */ 1588 static inline u32 signal_to_av(int sig) 1589 { 1590 u32 perm = 0; 1591 1592 switch (sig) { 1593 case SIGCHLD: 1594 /* Commonly granted from child to parent. */ 1595 perm = PROCESS__SIGCHLD; 1596 break; 1597 case SIGKILL: 1598 /* Cannot be caught or ignored */ 1599 perm = PROCESS__SIGKILL; 1600 break; 1601 case SIGSTOP: 1602 /* Cannot be caught or ignored */ 1603 perm = PROCESS__SIGSTOP; 1604 break; 1605 default: 1606 /* All other signals. */ 1607 perm = PROCESS__SIGNAL; 1608 break; 1609 } 1610 1611 return perm; 1612 } 1613 1614 #if CAP_LAST_CAP > 63 1615 #error Fix SELinux to handle capabilities > 63. 1616 #endif 1617 1618 /* Check whether a task is allowed to use a capability. */ 1619 static int cred_has_capability(const struct cred *cred, 1620 int cap, unsigned int opts, bool initns) 1621 { 1622 struct common_audit_data ad; 1623 struct av_decision avd; 1624 u16 sclass; 1625 u32 sid = cred_sid(cred); 1626 u32 av = CAP_TO_MASK(cap); 1627 int rc; 1628 1629 ad.type = LSM_AUDIT_DATA_CAP; 1630 ad.u.cap = cap; 1631 1632 switch (CAP_TO_INDEX(cap)) { 1633 case 0: 1634 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1635 break; 1636 case 1: 1637 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1638 break; 1639 default: 1640 pr_err("SELinux: out of range capability %d\n", cap); 1641 BUG(); 1642 return -EINVAL; 1643 } 1644 1645 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1646 if (!(opts & CAP_OPT_NOAUDIT)) { 1647 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1648 if (rc2) 1649 return rc2; 1650 } 1651 return rc; 1652 } 1653 1654 /* Check whether a task has a particular permission to an inode. 1655 The 'adp' parameter is optional and allows other audit 1656 data to be passed (e.g. the dentry). */ 1657 static int inode_has_perm(const struct cred *cred, 1658 struct inode *inode, 1659 u32 perms, 1660 struct common_audit_data *adp) 1661 { 1662 struct inode_security_struct *isec; 1663 u32 sid; 1664 1665 if (unlikely(IS_PRIVATE(inode))) 1666 return 0; 1667 1668 sid = cred_sid(cred); 1669 isec = selinux_inode(inode); 1670 1671 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1672 } 1673 1674 /* Same as inode_has_perm, but pass explicit audit data containing 1675 the dentry to help the auditing code to more easily generate the 1676 pathname if needed. */ 1677 static inline int dentry_has_perm(const struct cred *cred, 1678 struct dentry *dentry, 1679 u32 av) 1680 { 1681 struct inode *inode = d_backing_inode(dentry); 1682 struct common_audit_data ad; 1683 1684 ad.type = LSM_AUDIT_DATA_DENTRY; 1685 ad.u.dentry = dentry; 1686 __inode_security_revalidate(inode, dentry, true); 1687 return inode_has_perm(cred, inode, av, &ad); 1688 } 1689 1690 /* Same as inode_has_perm, but pass explicit audit data containing 1691 the path to help the auditing code to more easily generate the 1692 pathname if needed. */ 1693 static inline int path_has_perm(const struct cred *cred, 1694 const struct path *path, 1695 u32 av) 1696 { 1697 struct inode *inode = d_backing_inode(path->dentry); 1698 struct common_audit_data ad; 1699 1700 ad.type = LSM_AUDIT_DATA_PATH; 1701 ad.u.path = *path; 1702 __inode_security_revalidate(inode, path->dentry, true); 1703 return inode_has_perm(cred, inode, av, &ad); 1704 } 1705 1706 /* Same as path_has_perm, but uses the inode from the file struct. */ 1707 static inline int file_path_has_perm(const struct cred *cred, 1708 struct file *file, 1709 u32 av) 1710 { 1711 struct common_audit_data ad; 1712 1713 ad.type = LSM_AUDIT_DATA_FILE; 1714 ad.u.file = file; 1715 return inode_has_perm(cred, file_inode(file), av, &ad); 1716 } 1717 1718 #ifdef CONFIG_BPF_SYSCALL 1719 static int bpf_fd_pass(const struct file *file, u32 sid); 1720 #endif 1721 1722 /* Check whether a task can use an open file descriptor to 1723 access an inode in a given way. Check access to the 1724 descriptor itself, and then use dentry_has_perm to 1725 check a particular permission to the file. 1726 Access to the descriptor is implicitly granted if it 1727 has the same SID as the process. If av is zero, then 1728 access to the file is not checked, e.g. for cases 1729 where only the descriptor is affected like seek. */ 1730 static int file_has_perm(const struct cred *cred, 1731 struct file *file, 1732 u32 av) 1733 { 1734 struct file_security_struct *fsec = selinux_file(file); 1735 struct inode *inode = file_inode(file); 1736 struct common_audit_data ad; 1737 u32 sid = cred_sid(cred); 1738 int rc; 1739 1740 ad.type = LSM_AUDIT_DATA_FILE; 1741 ad.u.file = file; 1742 1743 if (sid != fsec->sid) { 1744 rc = avc_has_perm(sid, fsec->sid, 1745 SECCLASS_FD, 1746 FD__USE, 1747 &ad); 1748 if (rc) 1749 goto out; 1750 } 1751 1752 #ifdef CONFIG_BPF_SYSCALL 1753 rc = bpf_fd_pass(file, cred_sid(cred)); 1754 if (rc) 1755 return rc; 1756 #endif 1757 1758 /* av is zero if only checking access to the descriptor. */ 1759 rc = 0; 1760 if (av) 1761 rc = inode_has_perm(cred, inode, av, &ad); 1762 1763 out: 1764 return rc; 1765 } 1766 1767 /* 1768 * Determine the label for an inode that might be unioned. 1769 */ 1770 static int 1771 selinux_determine_inode_label(const struct task_security_struct *tsec, 1772 struct inode *dir, 1773 const struct qstr *name, u16 tclass, 1774 u32 *_new_isid) 1775 { 1776 const struct superblock_security_struct *sbsec = 1777 selinux_superblock(dir->i_sb); 1778 1779 if ((sbsec->flags & SE_SBINITIALIZED) && 1780 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1781 *_new_isid = sbsec->mntpoint_sid; 1782 } else if ((sbsec->flags & SBLABEL_MNT) && 1783 tsec->create_sid) { 1784 *_new_isid = tsec->create_sid; 1785 } else { 1786 const struct inode_security_struct *dsec = inode_security(dir); 1787 return security_transition_sid(tsec->sid, 1788 dsec->sid, tclass, 1789 name, _new_isid); 1790 } 1791 1792 return 0; 1793 } 1794 1795 /* Check whether a task can create a file. */ 1796 static int may_create(struct inode *dir, 1797 struct dentry *dentry, 1798 u16 tclass) 1799 { 1800 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1801 struct inode_security_struct *dsec; 1802 struct superblock_security_struct *sbsec; 1803 u32 sid, newsid; 1804 struct common_audit_data ad; 1805 int rc; 1806 1807 dsec = inode_security(dir); 1808 sbsec = selinux_superblock(dir->i_sb); 1809 1810 sid = tsec->sid; 1811 1812 ad.type = LSM_AUDIT_DATA_DENTRY; 1813 ad.u.dentry = dentry; 1814 1815 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1816 DIR__ADD_NAME | DIR__SEARCH, 1817 &ad); 1818 if (rc) 1819 return rc; 1820 1821 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1822 &newsid); 1823 if (rc) 1824 return rc; 1825 1826 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1827 if (rc) 1828 return rc; 1829 1830 return avc_has_perm(newsid, sbsec->sid, 1831 SECCLASS_FILESYSTEM, 1832 FILESYSTEM__ASSOCIATE, &ad); 1833 } 1834 1835 #define MAY_LINK 0 1836 #define MAY_UNLINK 1 1837 #define MAY_RMDIR 2 1838 1839 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1840 static int may_link(struct inode *dir, 1841 struct dentry *dentry, 1842 int kind) 1843 1844 { 1845 struct inode_security_struct *dsec, *isec; 1846 struct common_audit_data ad; 1847 u32 sid = current_sid(); 1848 u32 av; 1849 int rc; 1850 1851 dsec = inode_security(dir); 1852 isec = backing_inode_security(dentry); 1853 1854 ad.type = LSM_AUDIT_DATA_DENTRY; 1855 ad.u.dentry = dentry; 1856 1857 av = DIR__SEARCH; 1858 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1859 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1860 if (rc) 1861 return rc; 1862 1863 switch (kind) { 1864 case MAY_LINK: 1865 av = FILE__LINK; 1866 break; 1867 case MAY_UNLINK: 1868 av = FILE__UNLINK; 1869 break; 1870 case MAY_RMDIR: 1871 av = DIR__RMDIR; 1872 break; 1873 default: 1874 pr_warn("SELinux: %s: unrecognized kind %d\n", 1875 __func__, kind); 1876 return 0; 1877 } 1878 1879 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1880 return rc; 1881 } 1882 1883 static inline int may_rename(struct inode *old_dir, 1884 struct dentry *old_dentry, 1885 struct inode *new_dir, 1886 struct dentry *new_dentry) 1887 { 1888 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1889 struct common_audit_data ad; 1890 u32 sid = current_sid(); 1891 u32 av; 1892 int old_is_dir, new_is_dir; 1893 int rc; 1894 1895 old_dsec = inode_security(old_dir); 1896 old_isec = backing_inode_security(old_dentry); 1897 old_is_dir = d_is_dir(old_dentry); 1898 new_dsec = inode_security(new_dir); 1899 1900 ad.type = LSM_AUDIT_DATA_DENTRY; 1901 1902 ad.u.dentry = old_dentry; 1903 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1904 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1905 if (rc) 1906 return rc; 1907 rc = avc_has_perm(sid, old_isec->sid, 1908 old_isec->sclass, FILE__RENAME, &ad); 1909 if (rc) 1910 return rc; 1911 if (old_is_dir && new_dir != old_dir) { 1912 rc = avc_has_perm(sid, old_isec->sid, 1913 old_isec->sclass, DIR__REPARENT, &ad); 1914 if (rc) 1915 return rc; 1916 } 1917 1918 ad.u.dentry = new_dentry; 1919 av = DIR__ADD_NAME | DIR__SEARCH; 1920 if (d_is_positive(new_dentry)) 1921 av |= DIR__REMOVE_NAME; 1922 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1923 if (rc) 1924 return rc; 1925 if (d_is_positive(new_dentry)) { 1926 new_isec = backing_inode_security(new_dentry); 1927 new_is_dir = d_is_dir(new_dentry); 1928 rc = avc_has_perm(sid, new_isec->sid, 1929 new_isec->sclass, 1930 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1931 if (rc) 1932 return rc; 1933 } 1934 1935 return 0; 1936 } 1937 1938 /* Check whether a task can perform a filesystem operation. */ 1939 static int superblock_has_perm(const struct cred *cred, 1940 const struct super_block *sb, 1941 u32 perms, 1942 struct common_audit_data *ad) 1943 { 1944 struct superblock_security_struct *sbsec; 1945 u32 sid = cred_sid(cred); 1946 1947 sbsec = selinux_superblock(sb); 1948 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1949 } 1950 1951 /* Convert a Linux mode and permission mask to an access vector. */ 1952 static inline u32 file_mask_to_av(int mode, int mask) 1953 { 1954 u32 av = 0; 1955 1956 if (!S_ISDIR(mode)) { 1957 if (mask & MAY_EXEC) 1958 av |= FILE__EXECUTE; 1959 if (mask & MAY_READ) 1960 av |= FILE__READ; 1961 1962 if (mask & MAY_APPEND) 1963 av |= FILE__APPEND; 1964 else if (mask & MAY_WRITE) 1965 av |= FILE__WRITE; 1966 1967 } else { 1968 if (mask & MAY_EXEC) 1969 av |= DIR__SEARCH; 1970 if (mask & MAY_WRITE) 1971 av |= DIR__WRITE; 1972 if (mask & MAY_READ) 1973 av |= DIR__READ; 1974 } 1975 1976 return av; 1977 } 1978 1979 /* Convert a Linux file to an access vector. */ 1980 static inline u32 file_to_av(const struct file *file) 1981 { 1982 u32 av = 0; 1983 1984 if (file->f_mode & FMODE_READ) 1985 av |= FILE__READ; 1986 if (file->f_mode & FMODE_WRITE) { 1987 if (file->f_flags & O_APPEND) 1988 av |= FILE__APPEND; 1989 else 1990 av |= FILE__WRITE; 1991 } 1992 if (!av) { 1993 /* 1994 * Special file opened with flags 3 for ioctl-only use. 1995 */ 1996 av = FILE__IOCTL; 1997 } 1998 1999 return av; 2000 } 2001 2002 /* 2003 * Convert a file to an access vector and include the correct 2004 * open permission. 2005 */ 2006 static inline u32 open_file_to_av(struct file *file) 2007 { 2008 u32 av = file_to_av(file); 2009 struct inode *inode = file_inode(file); 2010 2011 if (selinux_policycap_openperm() && 2012 inode->i_sb->s_magic != SOCKFS_MAGIC) 2013 av |= FILE__OPEN; 2014 2015 return av; 2016 } 2017 2018 /* Hook functions begin here. */ 2019 2020 static int selinux_binder_set_context_mgr(const struct cred *mgr) 2021 { 2022 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, 2023 BINDER__SET_CONTEXT_MGR, NULL); 2024 } 2025 2026 static int selinux_binder_transaction(const struct cred *from, 2027 const struct cred *to) 2028 { 2029 u32 mysid = current_sid(); 2030 u32 fromsid = cred_sid(from); 2031 u32 tosid = cred_sid(to); 2032 int rc; 2033 2034 if (mysid != fromsid) { 2035 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2036 BINDER__IMPERSONATE, NULL); 2037 if (rc) 2038 return rc; 2039 } 2040 2041 return avc_has_perm(fromsid, tosid, 2042 SECCLASS_BINDER, BINDER__CALL, NULL); 2043 } 2044 2045 static int selinux_binder_transfer_binder(const struct cred *from, 2046 const struct cred *to) 2047 { 2048 return avc_has_perm(cred_sid(from), cred_sid(to), 2049 SECCLASS_BINDER, BINDER__TRANSFER, 2050 NULL); 2051 } 2052 2053 static int selinux_binder_transfer_file(const struct cred *from, 2054 const struct cred *to, 2055 const struct file *file) 2056 { 2057 u32 sid = cred_sid(to); 2058 struct file_security_struct *fsec = selinux_file(file); 2059 struct dentry *dentry = file->f_path.dentry; 2060 struct inode_security_struct *isec; 2061 struct common_audit_data ad; 2062 int rc; 2063 2064 ad.type = LSM_AUDIT_DATA_PATH; 2065 ad.u.path = file->f_path; 2066 2067 if (sid != fsec->sid) { 2068 rc = avc_has_perm(sid, fsec->sid, 2069 SECCLASS_FD, 2070 FD__USE, 2071 &ad); 2072 if (rc) 2073 return rc; 2074 } 2075 2076 #ifdef CONFIG_BPF_SYSCALL 2077 rc = bpf_fd_pass(file, sid); 2078 if (rc) 2079 return rc; 2080 #endif 2081 2082 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2083 return 0; 2084 2085 isec = backing_inode_security(dentry); 2086 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2087 &ad); 2088 } 2089 2090 static int selinux_ptrace_access_check(struct task_struct *child, 2091 unsigned int mode) 2092 { 2093 u32 sid = current_sid(); 2094 u32 csid = task_sid_obj(child); 2095 2096 if (mode & PTRACE_MODE_READ) 2097 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, 2098 NULL); 2099 2100 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, 2101 NULL); 2102 } 2103 2104 static int selinux_ptrace_traceme(struct task_struct *parent) 2105 { 2106 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), 2107 SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2108 } 2109 2110 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, 2111 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2112 { 2113 return avc_has_perm(current_sid(), task_sid_obj(target), 2114 SECCLASS_PROCESS, PROCESS__GETCAP, NULL); 2115 } 2116 2117 static int selinux_capset(struct cred *new, const struct cred *old, 2118 const kernel_cap_t *effective, 2119 const kernel_cap_t *inheritable, 2120 const kernel_cap_t *permitted) 2121 { 2122 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2123 PROCESS__SETCAP, NULL); 2124 } 2125 2126 /* 2127 * (This comment used to live with the selinux_task_setuid hook, 2128 * which was removed). 2129 * 2130 * Since setuid only affects the current process, and since the SELinux 2131 * controls are not based on the Linux identity attributes, SELinux does not 2132 * need to control this operation. However, SELinux does control the use of 2133 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2134 */ 2135 2136 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2137 int cap, unsigned int opts) 2138 { 2139 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2140 } 2141 2142 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb) 2143 { 2144 const struct cred *cred = current_cred(); 2145 int rc = 0; 2146 2147 if (!sb) 2148 return 0; 2149 2150 switch (cmds) { 2151 case Q_SYNC: 2152 case Q_QUOTAON: 2153 case Q_QUOTAOFF: 2154 case Q_SETINFO: 2155 case Q_SETQUOTA: 2156 case Q_XQUOTAOFF: 2157 case Q_XQUOTAON: 2158 case Q_XSETQLIM: 2159 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2160 break; 2161 case Q_GETFMT: 2162 case Q_GETINFO: 2163 case Q_GETQUOTA: 2164 case Q_XGETQUOTA: 2165 case Q_XGETQSTAT: 2166 case Q_XGETQSTATV: 2167 case Q_XGETNEXTQUOTA: 2168 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2169 break; 2170 default: 2171 rc = 0; /* let the kernel handle invalid cmds */ 2172 break; 2173 } 2174 return rc; 2175 } 2176 2177 static int selinux_quota_on(struct dentry *dentry) 2178 { 2179 const struct cred *cred = current_cred(); 2180 2181 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2182 } 2183 2184 static int selinux_syslog(int type) 2185 { 2186 switch (type) { 2187 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2188 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2189 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2190 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2191 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2192 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2193 /* Set level of messages printed to console */ 2194 case SYSLOG_ACTION_CONSOLE_LEVEL: 2195 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2196 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2197 NULL); 2198 } 2199 /* All other syslog types */ 2200 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2201 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2202 } 2203 2204 /* 2205 * Check that a process has enough memory to allocate a new virtual 2206 * mapping. 0 means there is enough memory for the allocation to 2207 * succeed and -ENOMEM implies there is not. 2208 * 2209 * Do not audit the selinux permission check, as this is applied to all 2210 * processes that allocate mappings. 2211 */ 2212 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2213 { 2214 int rc, cap_sys_admin = 0; 2215 2216 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2217 CAP_OPT_NOAUDIT, true); 2218 if (rc == 0) 2219 cap_sys_admin = 1; 2220 2221 return cap_sys_admin; 2222 } 2223 2224 /* binprm security operations */ 2225 2226 static u32 ptrace_parent_sid(void) 2227 { 2228 u32 sid = 0; 2229 struct task_struct *tracer; 2230 2231 rcu_read_lock(); 2232 tracer = ptrace_parent(current); 2233 if (tracer) 2234 sid = task_sid_obj(tracer); 2235 rcu_read_unlock(); 2236 2237 return sid; 2238 } 2239 2240 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2241 const struct task_security_struct *old_tsec, 2242 const struct task_security_struct *new_tsec) 2243 { 2244 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2245 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2246 int rc; 2247 u32 av; 2248 2249 if (!nnp && !nosuid) 2250 return 0; /* neither NNP nor nosuid */ 2251 2252 if (new_tsec->sid == old_tsec->sid) 2253 return 0; /* No change in credentials */ 2254 2255 /* 2256 * If the policy enables the nnp_nosuid_transition policy capability, 2257 * then we permit transitions under NNP or nosuid if the 2258 * policy allows the corresponding permission between 2259 * the old and new contexts. 2260 */ 2261 if (selinux_policycap_nnp_nosuid_transition()) { 2262 av = 0; 2263 if (nnp) 2264 av |= PROCESS2__NNP_TRANSITION; 2265 if (nosuid) 2266 av |= PROCESS2__NOSUID_TRANSITION; 2267 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2268 SECCLASS_PROCESS2, av, NULL); 2269 if (!rc) 2270 return 0; 2271 } 2272 2273 /* 2274 * We also permit NNP or nosuid transitions to bounded SIDs, 2275 * i.e. SIDs that are guaranteed to only be allowed a subset 2276 * of the permissions of the current SID. 2277 */ 2278 rc = security_bounded_transition(old_tsec->sid, 2279 new_tsec->sid); 2280 if (!rc) 2281 return 0; 2282 2283 /* 2284 * On failure, preserve the errno values for NNP vs nosuid. 2285 * NNP: Operation not permitted for caller. 2286 * nosuid: Permission denied to file. 2287 */ 2288 if (nnp) 2289 return -EPERM; 2290 return -EACCES; 2291 } 2292 2293 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2294 { 2295 const struct task_security_struct *old_tsec; 2296 struct task_security_struct *new_tsec; 2297 struct inode_security_struct *isec; 2298 struct common_audit_data ad; 2299 struct inode *inode = file_inode(bprm->file); 2300 int rc; 2301 2302 /* SELinux context only depends on initial program or script and not 2303 * the script interpreter */ 2304 2305 old_tsec = selinux_cred(current_cred()); 2306 new_tsec = selinux_cred(bprm->cred); 2307 isec = inode_security(inode); 2308 2309 /* Default to the current task SID. */ 2310 new_tsec->sid = old_tsec->sid; 2311 new_tsec->osid = old_tsec->sid; 2312 2313 /* Reset fs, key, and sock SIDs on execve. */ 2314 new_tsec->create_sid = 0; 2315 new_tsec->keycreate_sid = 0; 2316 new_tsec->sockcreate_sid = 0; 2317 2318 /* 2319 * Before policy is loaded, label any task outside kernel space 2320 * as SECINITSID_INIT, so that any userspace tasks surviving from 2321 * early boot end up with a label different from SECINITSID_KERNEL 2322 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL). 2323 */ 2324 if (!selinux_initialized()) { 2325 new_tsec->sid = SECINITSID_INIT; 2326 /* also clear the exec_sid just in case */ 2327 new_tsec->exec_sid = 0; 2328 return 0; 2329 } 2330 2331 if (old_tsec->exec_sid) { 2332 new_tsec->sid = old_tsec->exec_sid; 2333 /* Reset exec SID on execve. */ 2334 new_tsec->exec_sid = 0; 2335 2336 /* Fail on NNP or nosuid if not an allowed transition. */ 2337 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2338 if (rc) 2339 return rc; 2340 } else { 2341 /* Check for a default transition on this program. */ 2342 rc = security_transition_sid(old_tsec->sid, 2343 isec->sid, SECCLASS_PROCESS, NULL, 2344 &new_tsec->sid); 2345 if (rc) 2346 return rc; 2347 2348 /* 2349 * Fallback to old SID on NNP or nosuid if not an allowed 2350 * transition. 2351 */ 2352 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2353 if (rc) 2354 new_tsec->sid = old_tsec->sid; 2355 } 2356 2357 ad.type = LSM_AUDIT_DATA_FILE; 2358 ad.u.file = bprm->file; 2359 2360 if (new_tsec->sid == old_tsec->sid) { 2361 rc = avc_has_perm(old_tsec->sid, isec->sid, 2362 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2363 if (rc) 2364 return rc; 2365 } else { 2366 /* Check permissions for the transition. */ 2367 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2368 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2369 if (rc) 2370 return rc; 2371 2372 rc = avc_has_perm(new_tsec->sid, isec->sid, 2373 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2374 if (rc) 2375 return rc; 2376 2377 /* Check for shared state */ 2378 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2379 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2380 SECCLASS_PROCESS, PROCESS__SHARE, 2381 NULL); 2382 if (rc) 2383 return -EPERM; 2384 } 2385 2386 /* Make sure that anyone attempting to ptrace over a task that 2387 * changes its SID has the appropriate permit */ 2388 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2389 u32 ptsid = ptrace_parent_sid(); 2390 if (ptsid != 0) { 2391 rc = avc_has_perm(ptsid, new_tsec->sid, 2392 SECCLASS_PROCESS, 2393 PROCESS__PTRACE, NULL); 2394 if (rc) 2395 return -EPERM; 2396 } 2397 } 2398 2399 /* Clear any possibly unsafe personality bits on exec: */ 2400 bprm->per_clear |= PER_CLEAR_ON_SETID; 2401 2402 /* Enable secure mode for SIDs transitions unless 2403 the noatsecure permission is granted between 2404 the two SIDs, i.e. ahp returns 0. */ 2405 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2406 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2407 NULL); 2408 bprm->secureexec |= !!rc; 2409 } 2410 2411 return 0; 2412 } 2413 2414 static int match_file(const void *p, struct file *file, unsigned fd) 2415 { 2416 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2417 } 2418 2419 /* Derived from fs/exec.c:flush_old_files. */ 2420 static inline void flush_unauthorized_files(const struct cred *cred, 2421 struct files_struct *files) 2422 { 2423 struct file *file, *devnull = NULL; 2424 struct tty_struct *tty; 2425 int drop_tty = 0; 2426 unsigned n; 2427 2428 tty = get_current_tty(); 2429 if (tty) { 2430 spin_lock(&tty->files_lock); 2431 if (!list_empty(&tty->tty_files)) { 2432 struct tty_file_private *file_priv; 2433 2434 /* Revalidate access to controlling tty. 2435 Use file_path_has_perm on the tty path directly 2436 rather than using file_has_perm, as this particular 2437 open file may belong to another process and we are 2438 only interested in the inode-based check here. */ 2439 file_priv = list_first_entry(&tty->tty_files, 2440 struct tty_file_private, list); 2441 file = file_priv->file; 2442 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2443 drop_tty = 1; 2444 } 2445 spin_unlock(&tty->files_lock); 2446 tty_kref_put(tty); 2447 } 2448 /* Reset controlling tty. */ 2449 if (drop_tty) 2450 no_tty(); 2451 2452 /* Revalidate access to inherited open files. */ 2453 n = iterate_fd(files, 0, match_file, cred); 2454 if (!n) /* none found? */ 2455 return; 2456 2457 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2458 if (IS_ERR(devnull)) 2459 devnull = NULL; 2460 /* replace all the matching ones with this */ 2461 do { 2462 replace_fd(n - 1, devnull, 0); 2463 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2464 if (devnull) 2465 fput(devnull); 2466 } 2467 2468 /* 2469 * Prepare a process for imminent new credential changes due to exec 2470 */ 2471 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) 2472 { 2473 struct task_security_struct *new_tsec; 2474 struct rlimit *rlim, *initrlim; 2475 int rc, i; 2476 2477 new_tsec = selinux_cred(bprm->cred); 2478 if (new_tsec->sid == new_tsec->osid) 2479 return; 2480 2481 /* Close files for which the new task SID is not authorized. */ 2482 flush_unauthorized_files(bprm->cred, current->files); 2483 2484 /* Always clear parent death signal on SID transitions. */ 2485 current->pdeath_signal = 0; 2486 2487 /* Check whether the new SID can inherit resource limits from the old 2488 * SID. If not, reset all soft limits to the lower of the current 2489 * task's hard limit and the init task's soft limit. 2490 * 2491 * Note that the setting of hard limits (even to lower them) can be 2492 * controlled by the setrlimit check. The inclusion of the init task's 2493 * soft limit into the computation is to avoid resetting soft limits 2494 * higher than the default soft limit for cases where the default is 2495 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2496 */ 2497 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2498 PROCESS__RLIMITINH, NULL); 2499 if (rc) { 2500 /* protect against do_prlimit() */ 2501 task_lock(current); 2502 for (i = 0; i < RLIM_NLIMITS; i++) { 2503 rlim = current->signal->rlim + i; 2504 initrlim = init_task.signal->rlim + i; 2505 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2506 } 2507 task_unlock(current); 2508 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2509 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2510 } 2511 } 2512 2513 /* 2514 * Clean up the process immediately after the installation of new credentials 2515 * due to exec 2516 */ 2517 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) 2518 { 2519 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2520 u32 osid, sid; 2521 int rc; 2522 2523 osid = tsec->osid; 2524 sid = tsec->sid; 2525 2526 if (sid == osid) 2527 return; 2528 2529 /* Check whether the new SID can inherit signal state from the old SID. 2530 * If not, clear itimers to avoid subsequent signal generation and 2531 * flush and unblock signals. 2532 * 2533 * This must occur _after_ the task SID has been updated so that any 2534 * kill done after the flush will be checked against the new SID. 2535 */ 2536 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2537 if (rc) { 2538 clear_itimer(); 2539 2540 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); 2541 if (!fatal_signal_pending(current)) { 2542 flush_sigqueue(¤t->pending); 2543 flush_sigqueue(¤t->signal->shared_pending); 2544 flush_signal_handlers(current, 1); 2545 sigemptyset(¤t->blocked); 2546 recalc_sigpending(); 2547 } 2548 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); 2549 } 2550 2551 /* Wake up the parent if it is waiting so that it can recheck 2552 * wait permission to the new task SID. */ 2553 read_lock(&tasklist_lock); 2554 __wake_up_parent(current, unrcu_pointer(current->real_parent)); 2555 read_unlock(&tasklist_lock); 2556 } 2557 2558 /* superblock security operations */ 2559 2560 static int selinux_sb_alloc_security(struct super_block *sb) 2561 { 2562 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2563 2564 mutex_init(&sbsec->lock); 2565 INIT_LIST_HEAD(&sbsec->isec_head); 2566 spin_lock_init(&sbsec->isec_lock); 2567 sbsec->sid = SECINITSID_UNLABELED; 2568 sbsec->def_sid = SECINITSID_FILE; 2569 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2570 2571 return 0; 2572 } 2573 2574 static inline int opt_len(const char *s) 2575 { 2576 bool open_quote = false; 2577 int len; 2578 char c; 2579 2580 for (len = 0; (c = s[len]) != '\0'; len++) { 2581 if (c == '"') 2582 open_quote = !open_quote; 2583 if (c == ',' && !open_quote) 2584 break; 2585 } 2586 return len; 2587 } 2588 2589 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2590 { 2591 char *from = options; 2592 char *to = options; 2593 bool first = true; 2594 int rc; 2595 2596 while (1) { 2597 int len = opt_len(from); 2598 int token; 2599 char *arg = NULL; 2600 2601 token = match_opt_prefix(from, len, &arg); 2602 2603 if (token != Opt_error) { 2604 char *p, *q; 2605 2606 /* strip quotes */ 2607 if (arg) { 2608 for (p = q = arg; p < from + len; p++) { 2609 char c = *p; 2610 if (c != '"') 2611 *q++ = c; 2612 } 2613 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2614 if (!arg) { 2615 rc = -ENOMEM; 2616 goto free_opt; 2617 } 2618 } 2619 rc = selinux_add_opt(token, arg, mnt_opts); 2620 kfree(arg); 2621 arg = NULL; 2622 if (unlikely(rc)) { 2623 goto free_opt; 2624 } 2625 } else { 2626 if (!first) { // copy with preceding comma 2627 from--; 2628 len++; 2629 } 2630 if (to != from) 2631 memmove(to, from, len); 2632 to += len; 2633 first = false; 2634 } 2635 if (!from[len]) 2636 break; 2637 from += len + 1; 2638 } 2639 *to = '\0'; 2640 return 0; 2641 2642 free_opt: 2643 if (*mnt_opts) { 2644 selinux_free_mnt_opts(*mnt_opts); 2645 *mnt_opts = NULL; 2646 } 2647 return rc; 2648 } 2649 2650 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2651 { 2652 struct selinux_mnt_opts *opts = mnt_opts; 2653 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2654 2655 /* 2656 * Superblock not initialized (i.e. no options) - reject if any 2657 * options specified, otherwise accept. 2658 */ 2659 if (!(sbsec->flags & SE_SBINITIALIZED)) 2660 return opts ? 1 : 0; 2661 2662 /* 2663 * Superblock initialized and no options specified - reject if 2664 * superblock has any options set, otherwise accept. 2665 */ 2666 if (!opts) 2667 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2668 2669 if (opts->fscontext_sid) { 2670 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2671 opts->fscontext_sid)) 2672 return 1; 2673 } 2674 if (opts->context_sid) { 2675 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2676 opts->context_sid)) 2677 return 1; 2678 } 2679 if (opts->rootcontext_sid) { 2680 struct inode_security_struct *root_isec; 2681 2682 root_isec = backing_inode_security(sb->s_root); 2683 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2684 opts->rootcontext_sid)) 2685 return 1; 2686 } 2687 if (opts->defcontext_sid) { 2688 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2689 opts->defcontext_sid)) 2690 return 1; 2691 } 2692 return 0; 2693 } 2694 2695 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2696 { 2697 struct selinux_mnt_opts *opts = mnt_opts; 2698 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2699 2700 if (!(sbsec->flags & SE_SBINITIALIZED)) 2701 return 0; 2702 2703 if (!opts) 2704 return 0; 2705 2706 if (opts->fscontext_sid) { 2707 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2708 opts->fscontext_sid)) 2709 goto out_bad_option; 2710 } 2711 if (opts->context_sid) { 2712 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2713 opts->context_sid)) 2714 goto out_bad_option; 2715 } 2716 if (opts->rootcontext_sid) { 2717 struct inode_security_struct *root_isec; 2718 root_isec = backing_inode_security(sb->s_root); 2719 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2720 opts->rootcontext_sid)) 2721 goto out_bad_option; 2722 } 2723 if (opts->defcontext_sid) { 2724 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2725 opts->defcontext_sid)) 2726 goto out_bad_option; 2727 } 2728 return 0; 2729 2730 out_bad_option: 2731 pr_warn("SELinux: unable to change security options " 2732 "during remount (dev %s, type=%s)\n", sb->s_id, 2733 sb->s_type->name); 2734 return -EINVAL; 2735 } 2736 2737 static int selinux_sb_kern_mount(const struct super_block *sb) 2738 { 2739 const struct cred *cred = current_cred(); 2740 struct common_audit_data ad; 2741 2742 ad.type = LSM_AUDIT_DATA_DENTRY; 2743 ad.u.dentry = sb->s_root; 2744 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2745 } 2746 2747 static int selinux_sb_statfs(struct dentry *dentry) 2748 { 2749 const struct cred *cred = current_cred(); 2750 struct common_audit_data ad; 2751 2752 ad.type = LSM_AUDIT_DATA_DENTRY; 2753 ad.u.dentry = dentry->d_sb->s_root; 2754 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2755 } 2756 2757 static int selinux_mount(const char *dev_name, 2758 const struct path *path, 2759 const char *type, 2760 unsigned long flags, 2761 void *data) 2762 { 2763 const struct cred *cred = current_cred(); 2764 2765 if (flags & MS_REMOUNT) 2766 return superblock_has_perm(cred, path->dentry->d_sb, 2767 FILESYSTEM__REMOUNT, NULL); 2768 else 2769 return path_has_perm(cred, path, FILE__MOUNTON); 2770 } 2771 2772 static int selinux_move_mount(const struct path *from_path, 2773 const struct path *to_path) 2774 { 2775 const struct cred *cred = current_cred(); 2776 2777 return path_has_perm(cred, to_path, FILE__MOUNTON); 2778 } 2779 2780 static int selinux_umount(struct vfsmount *mnt, int flags) 2781 { 2782 const struct cred *cred = current_cred(); 2783 2784 return superblock_has_perm(cred, mnt->mnt_sb, 2785 FILESYSTEM__UNMOUNT, NULL); 2786 } 2787 2788 static int selinux_fs_context_submount(struct fs_context *fc, 2789 struct super_block *reference) 2790 { 2791 const struct superblock_security_struct *sbsec = selinux_superblock(reference); 2792 struct selinux_mnt_opts *opts; 2793 2794 /* 2795 * Ensure that fc->security remains NULL when no options are set 2796 * as expected by selinux_set_mnt_opts(). 2797 */ 2798 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) 2799 return 0; 2800 2801 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 2802 if (!opts) 2803 return -ENOMEM; 2804 2805 if (sbsec->flags & FSCONTEXT_MNT) 2806 opts->fscontext_sid = sbsec->sid; 2807 if (sbsec->flags & CONTEXT_MNT) 2808 opts->context_sid = sbsec->mntpoint_sid; 2809 if (sbsec->flags & DEFCONTEXT_MNT) 2810 opts->defcontext_sid = sbsec->def_sid; 2811 fc->security = opts; 2812 return 0; 2813 } 2814 2815 static int selinux_fs_context_dup(struct fs_context *fc, 2816 struct fs_context *src_fc) 2817 { 2818 const struct selinux_mnt_opts *src = src_fc->security; 2819 2820 if (!src) 2821 return 0; 2822 2823 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); 2824 return fc->security ? 0 : -ENOMEM; 2825 } 2826 2827 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2828 fsparam_string(CONTEXT_STR, Opt_context), 2829 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2830 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2831 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2832 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2833 {} 2834 }; 2835 2836 static int selinux_fs_context_parse_param(struct fs_context *fc, 2837 struct fs_parameter *param) 2838 { 2839 struct fs_parse_result result; 2840 int opt; 2841 2842 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2843 if (opt < 0) 2844 return opt; 2845 2846 return selinux_add_opt(opt, param->string, &fc->security); 2847 } 2848 2849 /* inode security operations */ 2850 2851 static int selinux_inode_alloc_security(struct inode *inode) 2852 { 2853 struct inode_security_struct *isec = selinux_inode(inode); 2854 u32 sid = current_sid(); 2855 2856 spin_lock_init(&isec->lock); 2857 INIT_LIST_HEAD(&isec->list); 2858 isec->inode = inode; 2859 isec->sid = SECINITSID_UNLABELED; 2860 isec->sclass = SECCLASS_FILE; 2861 isec->task_sid = sid; 2862 isec->initialized = LABEL_INVALID; 2863 2864 return 0; 2865 } 2866 2867 static void selinux_inode_free_security(struct inode *inode) 2868 { 2869 inode_free_security(inode); 2870 } 2871 2872 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2873 const struct qstr *name, 2874 const char **xattr_name, void **ctx, 2875 u32 *ctxlen) 2876 { 2877 u32 newsid; 2878 int rc; 2879 2880 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2881 d_inode(dentry->d_parent), name, 2882 inode_mode_to_security_class(mode), 2883 &newsid); 2884 if (rc) 2885 return rc; 2886 2887 if (xattr_name) 2888 *xattr_name = XATTR_NAME_SELINUX; 2889 2890 return security_sid_to_context(newsid, (char **)ctx, 2891 ctxlen); 2892 } 2893 2894 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2895 struct qstr *name, 2896 const struct cred *old, 2897 struct cred *new) 2898 { 2899 u32 newsid; 2900 int rc; 2901 struct task_security_struct *tsec; 2902 2903 rc = selinux_determine_inode_label(selinux_cred(old), 2904 d_inode(dentry->d_parent), name, 2905 inode_mode_to_security_class(mode), 2906 &newsid); 2907 if (rc) 2908 return rc; 2909 2910 tsec = selinux_cred(new); 2911 tsec->create_sid = newsid; 2912 return 0; 2913 } 2914 2915 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2916 const struct qstr *qstr, 2917 struct xattr *xattrs, int *xattr_count) 2918 { 2919 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2920 struct superblock_security_struct *sbsec; 2921 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); 2922 u32 newsid, clen; 2923 u16 newsclass; 2924 int rc; 2925 char *context; 2926 2927 sbsec = selinux_superblock(dir->i_sb); 2928 2929 newsid = tsec->create_sid; 2930 newsclass = inode_mode_to_security_class(inode->i_mode); 2931 rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid); 2932 if (rc) 2933 return rc; 2934 2935 /* Possibly defer initialization to selinux_complete_init. */ 2936 if (sbsec->flags & SE_SBINITIALIZED) { 2937 struct inode_security_struct *isec = selinux_inode(inode); 2938 isec->sclass = newsclass; 2939 isec->sid = newsid; 2940 isec->initialized = LABEL_INITIALIZED; 2941 } 2942 2943 if (!selinux_initialized() || 2944 !(sbsec->flags & SBLABEL_MNT)) 2945 return -EOPNOTSUPP; 2946 2947 if (xattr) { 2948 rc = security_sid_to_context_force(newsid, 2949 &context, &clen); 2950 if (rc) 2951 return rc; 2952 xattr->value = context; 2953 xattr->value_len = clen; 2954 xattr->name = XATTR_SELINUX_SUFFIX; 2955 } 2956 2957 return 0; 2958 } 2959 2960 static int selinux_inode_init_security_anon(struct inode *inode, 2961 const struct qstr *name, 2962 const struct inode *context_inode) 2963 { 2964 u32 sid = current_sid(); 2965 struct common_audit_data ad; 2966 struct inode_security_struct *isec; 2967 int rc; 2968 2969 if (unlikely(!selinux_initialized())) 2970 return 0; 2971 2972 isec = selinux_inode(inode); 2973 2974 /* 2975 * We only get here once per ephemeral inode. The inode has 2976 * been initialized via inode_alloc_security but is otherwise 2977 * untouched. 2978 */ 2979 2980 if (context_inode) { 2981 struct inode_security_struct *context_isec = 2982 selinux_inode(context_inode); 2983 if (context_isec->initialized != LABEL_INITIALIZED) { 2984 pr_err("SELinux: context_inode is not initialized\n"); 2985 return -EACCES; 2986 } 2987 2988 isec->sclass = context_isec->sclass; 2989 isec->sid = context_isec->sid; 2990 } else { 2991 isec->sclass = SECCLASS_ANON_INODE; 2992 rc = security_transition_sid( 2993 sid, sid, 2994 isec->sclass, name, &isec->sid); 2995 if (rc) 2996 return rc; 2997 } 2998 2999 isec->initialized = LABEL_INITIALIZED; 3000 /* 3001 * Now that we've initialized security, check whether we're 3002 * allowed to actually create this type of anonymous inode. 3003 */ 3004 3005 ad.type = LSM_AUDIT_DATA_ANONINODE; 3006 ad.u.anonclass = name ? (const char *)name->name : "?"; 3007 3008 return avc_has_perm(sid, 3009 isec->sid, 3010 isec->sclass, 3011 FILE__CREATE, 3012 &ad); 3013 } 3014 3015 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3016 { 3017 return may_create(dir, dentry, SECCLASS_FILE); 3018 } 3019 3020 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3021 { 3022 return may_link(dir, old_dentry, MAY_LINK); 3023 } 3024 3025 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3026 { 3027 return may_link(dir, dentry, MAY_UNLINK); 3028 } 3029 3030 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3031 { 3032 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3033 } 3034 3035 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3036 { 3037 return may_create(dir, dentry, SECCLASS_DIR); 3038 } 3039 3040 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3041 { 3042 return may_link(dir, dentry, MAY_RMDIR); 3043 } 3044 3045 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3046 { 3047 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3048 } 3049 3050 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3051 struct inode *new_inode, struct dentry *new_dentry) 3052 { 3053 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3054 } 3055 3056 static int selinux_inode_readlink(struct dentry *dentry) 3057 { 3058 const struct cred *cred = current_cred(); 3059 3060 return dentry_has_perm(cred, dentry, FILE__READ); 3061 } 3062 3063 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3064 bool rcu) 3065 { 3066 struct common_audit_data ad; 3067 struct inode_security_struct *isec; 3068 u32 sid = current_sid(); 3069 3070 ad.type = LSM_AUDIT_DATA_DENTRY; 3071 ad.u.dentry = dentry; 3072 isec = inode_security_rcu(inode, rcu); 3073 if (IS_ERR(isec)) 3074 return PTR_ERR(isec); 3075 3076 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); 3077 } 3078 3079 static noinline int audit_inode_permission(struct inode *inode, 3080 u32 perms, u32 audited, u32 denied, 3081 int result) 3082 { 3083 struct common_audit_data ad; 3084 struct inode_security_struct *isec = selinux_inode(inode); 3085 3086 ad.type = LSM_AUDIT_DATA_INODE; 3087 ad.u.inode = inode; 3088 3089 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3090 audited, denied, result, &ad); 3091 } 3092 3093 static int selinux_inode_permission(struct inode *inode, int mask) 3094 { 3095 u32 perms; 3096 bool from_access; 3097 bool no_block = mask & MAY_NOT_BLOCK; 3098 struct inode_security_struct *isec; 3099 u32 sid = current_sid(); 3100 struct av_decision avd; 3101 int rc, rc2; 3102 u32 audited, denied; 3103 3104 from_access = mask & MAY_ACCESS; 3105 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3106 3107 /* No permission to check. Existence test. */ 3108 if (!mask) 3109 return 0; 3110 3111 if (unlikely(IS_PRIVATE(inode))) 3112 return 0; 3113 3114 perms = file_mask_to_av(inode->i_mode, mask); 3115 3116 isec = inode_security_rcu(inode, no_block); 3117 if (IS_ERR(isec)) 3118 return PTR_ERR(isec); 3119 3120 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, 3121 &avd); 3122 audited = avc_audit_required(perms, &avd, rc, 3123 from_access ? FILE__AUDIT_ACCESS : 0, 3124 &denied); 3125 if (likely(!audited)) 3126 return rc; 3127 3128 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3129 if (rc2) 3130 return rc2; 3131 return rc; 3132 } 3133 3134 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 3135 struct iattr *iattr) 3136 { 3137 const struct cred *cred = current_cred(); 3138 struct inode *inode = d_backing_inode(dentry); 3139 unsigned int ia_valid = iattr->ia_valid; 3140 __u32 av = FILE__WRITE; 3141 3142 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3143 if (ia_valid & ATTR_FORCE) { 3144 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3145 ATTR_FORCE); 3146 if (!ia_valid) 3147 return 0; 3148 } 3149 3150 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3151 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3152 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3153 3154 if (selinux_policycap_openperm() && 3155 inode->i_sb->s_magic != SOCKFS_MAGIC && 3156 (ia_valid & ATTR_SIZE) && 3157 !(ia_valid & ATTR_FILE)) 3158 av |= FILE__OPEN; 3159 3160 return dentry_has_perm(cred, dentry, av); 3161 } 3162 3163 static int selinux_inode_getattr(const struct path *path) 3164 { 3165 return path_has_perm(current_cred(), path, FILE__GETATTR); 3166 } 3167 3168 static bool has_cap_mac_admin(bool audit) 3169 { 3170 const struct cred *cred = current_cred(); 3171 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3172 3173 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3174 return false; 3175 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3176 return false; 3177 return true; 3178 } 3179 3180 /** 3181 * selinux_inode_xattr_skipcap - Skip the xattr capability checks? 3182 * @name: name of the xattr 3183 * 3184 * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs 3185 * named @name; the LSM layer should avoid enforcing any traditional 3186 * capability based access controls on this xattr. Returns 0 to indicate that 3187 * SELinux does not "own" the access control rights to xattrs named @name and is 3188 * deferring to the LSM layer for further access controls, including capability 3189 * based controls. 3190 */ 3191 static int selinux_inode_xattr_skipcap(const char *name) 3192 { 3193 /* require capability check if not a selinux xattr */ 3194 return !strcmp(name, XATTR_NAME_SELINUX); 3195 } 3196 3197 static int selinux_inode_setxattr(struct mnt_idmap *idmap, 3198 struct dentry *dentry, const char *name, 3199 const void *value, size_t size, int flags) 3200 { 3201 struct inode *inode = d_backing_inode(dentry); 3202 struct inode_security_struct *isec; 3203 struct superblock_security_struct *sbsec; 3204 struct common_audit_data ad; 3205 u32 newsid, sid = current_sid(); 3206 int rc = 0; 3207 3208 /* if not a selinux xattr, only check the ordinary setattr perm */ 3209 if (strcmp(name, XATTR_NAME_SELINUX)) 3210 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3211 3212 if (!selinux_initialized()) 3213 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); 3214 3215 sbsec = selinux_superblock(inode->i_sb); 3216 if (!(sbsec->flags & SBLABEL_MNT)) 3217 return -EOPNOTSUPP; 3218 3219 if (!inode_owner_or_capable(idmap, inode)) 3220 return -EPERM; 3221 3222 ad.type = LSM_AUDIT_DATA_DENTRY; 3223 ad.u.dentry = dentry; 3224 3225 isec = backing_inode_security(dentry); 3226 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3227 FILE__RELABELFROM, &ad); 3228 if (rc) 3229 return rc; 3230 3231 rc = security_context_to_sid(value, size, &newsid, 3232 GFP_KERNEL); 3233 if (rc == -EINVAL) { 3234 if (!has_cap_mac_admin(true)) { 3235 struct audit_buffer *ab; 3236 size_t audit_size; 3237 3238 /* We strip a nul only if it is at the end, otherwise the 3239 * context contains a nul and we should audit that */ 3240 if (value) { 3241 const char *str = value; 3242 3243 if (str[size - 1] == '\0') 3244 audit_size = size - 1; 3245 else 3246 audit_size = size; 3247 } else { 3248 audit_size = 0; 3249 } 3250 ab = audit_log_start(audit_context(), 3251 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3252 if (!ab) 3253 return rc; 3254 audit_log_format(ab, "op=setxattr invalid_context="); 3255 audit_log_n_untrustedstring(ab, value, audit_size); 3256 audit_log_end(ab); 3257 3258 return rc; 3259 } 3260 rc = security_context_to_sid_force(value, 3261 size, &newsid); 3262 } 3263 if (rc) 3264 return rc; 3265 3266 rc = avc_has_perm(sid, newsid, isec->sclass, 3267 FILE__RELABELTO, &ad); 3268 if (rc) 3269 return rc; 3270 3271 rc = security_validate_transition(isec->sid, newsid, 3272 sid, isec->sclass); 3273 if (rc) 3274 return rc; 3275 3276 return avc_has_perm(newsid, 3277 sbsec->sid, 3278 SECCLASS_FILESYSTEM, 3279 FILESYSTEM__ASSOCIATE, 3280 &ad); 3281 } 3282 3283 static int selinux_inode_set_acl(struct mnt_idmap *idmap, 3284 struct dentry *dentry, const char *acl_name, 3285 struct posix_acl *kacl) 3286 { 3287 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3288 } 3289 3290 static int selinux_inode_get_acl(struct mnt_idmap *idmap, 3291 struct dentry *dentry, const char *acl_name) 3292 { 3293 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); 3294 } 3295 3296 static int selinux_inode_remove_acl(struct mnt_idmap *idmap, 3297 struct dentry *dentry, const char *acl_name) 3298 { 3299 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3300 } 3301 3302 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3303 const void *value, size_t size, 3304 int flags) 3305 { 3306 struct inode *inode = d_backing_inode(dentry); 3307 struct inode_security_struct *isec; 3308 u32 newsid; 3309 int rc; 3310 3311 if (strcmp(name, XATTR_NAME_SELINUX)) { 3312 /* Not an attribute we recognize, so nothing to do. */ 3313 return; 3314 } 3315 3316 if (!selinux_initialized()) { 3317 /* If we haven't even been initialized, then we can't validate 3318 * against a policy, so leave the label as invalid. It may 3319 * resolve to a valid label on the next revalidation try if 3320 * we've since initialized. 3321 */ 3322 return; 3323 } 3324 3325 rc = security_context_to_sid_force(value, size, 3326 &newsid); 3327 if (rc) { 3328 pr_err("SELinux: unable to map context to SID" 3329 "for (%s, %lu), rc=%d\n", 3330 inode->i_sb->s_id, inode->i_ino, -rc); 3331 return; 3332 } 3333 3334 isec = backing_inode_security(dentry); 3335 spin_lock(&isec->lock); 3336 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3337 isec->sid = newsid; 3338 isec->initialized = LABEL_INITIALIZED; 3339 spin_unlock(&isec->lock); 3340 } 3341 3342 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3343 { 3344 const struct cred *cred = current_cred(); 3345 3346 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3347 } 3348 3349 static int selinux_inode_listxattr(struct dentry *dentry) 3350 { 3351 const struct cred *cred = current_cred(); 3352 3353 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3354 } 3355 3356 static int selinux_inode_removexattr(struct mnt_idmap *idmap, 3357 struct dentry *dentry, const char *name) 3358 { 3359 /* if not a selinux xattr, only check the ordinary setattr perm */ 3360 if (strcmp(name, XATTR_NAME_SELINUX)) 3361 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3362 3363 if (!selinux_initialized()) 3364 return 0; 3365 3366 /* No one is allowed to remove a SELinux security label. 3367 You can change the label, but all data must be labeled. */ 3368 return -EACCES; 3369 } 3370 3371 static int selinux_path_notify(const struct path *path, u64 mask, 3372 unsigned int obj_type) 3373 { 3374 int ret; 3375 u32 perm; 3376 3377 struct common_audit_data ad; 3378 3379 ad.type = LSM_AUDIT_DATA_PATH; 3380 ad.u.path = *path; 3381 3382 /* 3383 * Set permission needed based on the type of mark being set. 3384 * Performs an additional check for sb watches. 3385 */ 3386 switch (obj_type) { 3387 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3388 perm = FILE__WATCH_MOUNT; 3389 break; 3390 case FSNOTIFY_OBJ_TYPE_SB: 3391 perm = FILE__WATCH_SB; 3392 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3393 FILESYSTEM__WATCH, &ad); 3394 if (ret) 3395 return ret; 3396 break; 3397 case FSNOTIFY_OBJ_TYPE_INODE: 3398 perm = FILE__WATCH; 3399 break; 3400 default: 3401 return -EINVAL; 3402 } 3403 3404 /* blocking watches require the file:watch_with_perm permission */ 3405 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3406 perm |= FILE__WATCH_WITH_PERM; 3407 3408 /* watches on read-like events need the file:watch_reads permission */ 3409 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3410 perm |= FILE__WATCH_READS; 3411 3412 return path_has_perm(current_cred(), path, perm); 3413 } 3414 3415 /* 3416 * Copy the inode security context value to the user. 3417 * 3418 * Permission check is handled by selinux_inode_getxattr hook. 3419 */ 3420 static int selinux_inode_getsecurity(struct mnt_idmap *idmap, 3421 struct inode *inode, const char *name, 3422 void **buffer, bool alloc) 3423 { 3424 u32 size; 3425 int error; 3426 char *context = NULL; 3427 struct inode_security_struct *isec; 3428 3429 /* 3430 * If we're not initialized yet, then we can't validate contexts, so 3431 * just let vfs_getxattr fall back to using the on-disk xattr. 3432 */ 3433 if (!selinux_initialized() || 3434 strcmp(name, XATTR_SELINUX_SUFFIX)) 3435 return -EOPNOTSUPP; 3436 3437 /* 3438 * If the caller has CAP_MAC_ADMIN, then get the raw context 3439 * value even if it is not defined by current policy; otherwise, 3440 * use the in-core value under current policy. 3441 * Use the non-auditing forms of the permission checks since 3442 * getxattr may be called by unprivileged processes commonly 3443 * and lack of permission just means that we fall back to the 3444 * in-core context value, not a denial. 3445 */ 3446 isec = inode_security(inode); 3447 if (has_cap_mac_admin(false)) 3448 error = security_sid_to_context_force(isec->sid, &context, 3449 &size); 3450 else 3451 error = security_sid_to_context(isec->sid, 3452 &context, &size); 3453 if (error) 3454 return error; 3455 error = size; 3456 if (alloc) { 3457 *buffer = context; 3458 goto out_nofree; 3459 } 3460 kfree(context); 3461 out_nofree: 3462 return error; 3463 } 3464 3465 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3466 const void *value, size_t size, int flags) 3467 { 3468 struct inode_security_struct *isec = inode_security_novalidate(inode); 3469 struct superblock_security_struct *sbsec; 3470 u32 newsid; 3471 int rc; 3472 3473 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3474 return -EOPNOTSUPP; 3475 3476 sbsec = selinux_superblock(inode->i_sb); 3477 if (!(sbsec->flags & SBLABEL_MNT)) 3478 return -EOPNOTSUPP; 3479 3480 if (!value || !size) 3481 return -EACCES; 3482 3483 rc = security_context_to_sid(value, size, &newsid, 3484 GFP_KERNEL); 3485 if (rc) 3486 return rc; 3487 3488 spin_lock(&isec->lock); 3489 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3490 isec->sid = newsid; 3491 isec->initialized = LABEL_INITIALIZED; 3492 spin_unlock(&isec->lock); 3493 return 0; 3494 } 3495 3496 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3497 { 3498 const int len = sizeof(XATTR_NAME_SELINUX); 3499 3500 if (!selinux_initialized()) 3501 return 0; 3502 3503 if (buffer && len <= buffer_size) 3504 memcpy(buffer, XATTR_NAME_SELINUX, len); 3505 return len; 3506 } 3507 3508 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3509 { 3510 struct inode_security_struct *isec = inode_security_novalidate(inode); 3511 *secid = isec->sid; 3512 } 3513 3514 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3515 { 3516 u32 sid; 3517 struct task_security_struct *tsec; 3518 struct cred *new_creds = *new; 3519 3520 if (new_creds == NULL) { 3521 new_creds = prepare_creds(); 3522 if (!new_creds) 3523 return -ENOMEM; 3524 } 3525 3526 tsec = selinux_cred(new_creds); 3527 /* Get label from overlay inode and set it in create_sid */ 3528 selinux_inode_getsecid(d_inode(src), &sid); 3529 tsec->create_sid = sid; 3530 *new = new_creds; 3531 return 0; 3532 } 3533 3534 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name) 3535 { 3536 /* The copy_up hook above sets the initial context on an inode, but we 3537 * don't then want to overwrite it by blindly copying all the lower 3538 * xattrs up. Instead, filter out SELinux-related xattrs following 3539 * policy load. 3540 */ 3541 if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0) 3542 return 1; /* Discard */ 3543 /* 3544 * Any other attribute apart from SELINUX is not claimed, supported 3545 * by selinux. 3546 */ 3547 return -EOPNOTSUPP; 3548 } 3549 3550 /* kernfs node operations */ 3551 3552 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3553 struct kernfs_node *kn) 3554 { 3555 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3556 u32 parent_sid, newsid, clen; 3557 int rc; 3558 char *context; 3559 3560 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3561 if (rc == -ENODATA) 3562 return 0; 3563 else if (rc < 0) 3564 return rc; 3565 3566 clen = (u32)rc; 3567 context = kmalloc(clen, GFP_KERNEL); 3568 if (!context) 3569 return -ENOMEM; 3570 3571 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3572 if (rc < 0) { 3573 kfree(context); 3574 return rc; 3575 } 3576 3577 rc = security_context_to_sid(context, clen, &parent_sid, 3578 GFP_KERNEL); 3579 kfree(context); 3580 if (rc) 3581 return rc; 3582 3583 if (tsec->create_sid) { 3584 newsid = tsec->create_sid; 3585 } else { 3586 u16 secclass = inode_mode_to_security_class(kn->mode); 3587 struct qstr q; 3588 3589 q.name = kn->name; 3590 q.hash_len = hashlen_string(kn_dir, kn->name); 3591 3592 rc = security_transition_sid(tsec->sid, 3593 parent_sid, secclass, &q, 3594 &newsid); 3595 if (rc) 3596 return rc; 3597 } 3598 3599 rc = security_sid_to_context_force(newsid, 3600 &context, &clen); 3601 if (rc) 3602 return rc; 3603 3604 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3605 XATTR_CREATE); 3606 kfree(context); 3607 return rc; 3608 } 3609 3610 3611 /* file security operations */ 3612 3613 static int selinux_revalidate_file_permission(struct file *file, int mask) 3614 { 3615 const struct cred *cred = current_cred(); 3616 struct inode *inode = file_inode(file); 3617 3618 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3619 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3620 mask |= MAY_APPEND; 3621 3622 return file_has_perm(cred, file, 3623 file_mask_to_av(inode->i_mode, mask)); 3624 } 3625 3626 static int selinux_file_permission(struct file *file, int mask) 3627 { 3628 struct inode *inode = file_inode(file); 3629 struct file_security_struct *fsec = selinux_file(file); 3630 struct inode_security_struct *isec; 3631 u32 sid = current_sid(); 3632 3633 if (!mask) 3634 /* No permission to check. Existence test. */ 3635 return 0; 3636 3637 isec = inode_security(inode); 3638 if (sid == fsec->sid && fsec->isid == isec->sid && 3639 fsec->pseqno == avc_policy_seqno()) 3640 /* No change since file_open check. */ 3641 return 0; 3642 3643 return selinux_revalidate_file_permission(file, mask); 3644 } 3645 3646 static int selinux_file_alloc_security(struct file *file) 3647 { 3648 struct file_security_struct *fsec = selinux_file(file); 3649 u32 sid = current_sid(); 3650 3651 fsec->sid = sid; 3652 fsec->fown_sid = sid; 3653 3654 return 0; 3655 } 3656 3657 /* 3658 * Check whether a task has the ioctl permission and cmd 3659 * operation to an inode. 3660 */ 3661 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3662 u32 requested, u16 cmd) 3663 { 3664 struct common_audit_data ad; 3665 struct file_security_struct *fsec = selinux_file(file); 3666 struct inode *inode = file_inode(file); 3667 struct inode_security_struct *isec; 3668 struct lsm_ioctlop_audit ioctl; 3669 u32 ssid = cred_sid(cred); 3670 int rc; 3671 u8 driver = cmd >> 8; 3672 u8 xperm = cmd & 0xff; 3673 3674 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3675 ad.u.op = &ioctl; 3676 ad.u.op->cmd = cmd; 3677 ad.u.op->path = file->f_path; 3678 3679 if (ssid != fsec->sid) { 3680 rc = avc_has_perm(ssid, fsec->sid, 3681 SECCLASS_FD, 3682 FD__USE, 3683 &ad); 3684 if (rc) 3685 goto out; 3686 } 3687 3688 if (unlikely(IS_PRIVATE(inode))) 3689 return 0; 3690 3691 isec = inode_security(inode); 3692 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3693 requested, driver, xperm, &ad); 3694 out: 3695 return rc; 3696 } 3697 3698 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3699 unsigned long arg) 3700 { 3701 const struct cred *cred = current_cred(); 3702 int error = 0; 3703 3704 switch (cmd) { 3705 case FIONREAD: 3706 case FIBMAP: 3707 case FIGETBSZ: 3708 case FS_IOC_GETFLAGS: 3709 case FS_IOC_GETVERSION: 3710 error = file_has_perm(cred, file, FILE__GETATTR); 3711 break; 3712 3713 case FS_IOC_SETFLAGS: 3714 case FS_IOC_SETVERSION: 3715 error = file_has_perm(cred, file, FILE__SETATTR); 3716 break; 3717 3718 /* sys_ioctl() checks */ 3719 case FIONBIO: 3720 case FIOASYNC: 3721 error = file_has_perm(cred, file, 0); 3722 break; 3723 3724 case KDSKBENT: 3725 case KDSKBSENT: 3726 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3727 CAP_OPT_NONE, true); 3728 break; 3729 3730 case FIOCLEX: 3731 case FIONCLEX: 3732 if (!selinux_policycap_ioctl_skip_cloexec()) 3733 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3734 break; 3735 3736 /* default case assumes that the command will go 3737 * to the file's ioctl() function. 3738 */ 3739 default: 3740 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3741 } 3742 return error; 3743 } 3744 3745 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd, 3746 unsigned long arg) 3747 { 3748 /* 3749 * If we are in a 64-bit kernel running 32-bit userspace, we need to 3750 * make sure we don't compare 32-bit flags to 64-bit flags. 3751 */ 3752 switch (cmd) { 3753 case FS_IOC32_GETFLAGS: 3754 cmd = FS_IOC_GETFLAGS; 3755 break; 3756 case FS_IOC32_SETFLAGS: 3757 cmd = FS_IOC_SETFLAGS; 3758 break; 3759 case FS_IOC32_GETVERSION: 3760 cmd = FS_IOC_GETVERSION; 3761 break; 3762 case FS_IOC32_SETVERSION: 3763 cmd = FS_IOC_SETVERSION; 3764 break; 3765 default: 3766 break; 3767 } 3768 3769 return selinux_file_ioctl(file, cmd, arg); 3770 } 3771 3772 static int default_noexec __ro_after_init; 3773 3774 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3775 { 3776 const struct cred *cred = current_cred(); 3777 u32 sid = cred_sid(cred); 3778 int rc = 0; 3779 3780 if (default_noexec && 3781 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3782 (!shared && (prot & PROT_WRITE)))) { 3783 /* 3784 * We are making executable an anonymous mapping or a 3785 * private file mapping that will also be writable. 3786 * This has an additional check. 3787 */ 3788 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3789 PROCESS__EXECMEM, NULL); 3790 if (rc) 3791 goto error; 3792 } 3793 3794 if (file) { 3795 /* read access is always possible with a mapping */ 3796 u32 av = FILE__READ; 3797 3798 /* write access only matters if the mapping is shared */ 3799 if (shared && (prot & PROT_WRITE)) 3800 av |= FILE__WRITE; 3801 3802 if (prot & PROT_EXEC) 3803 av |= FILE__EXECUTE; 3804 3805 return file_has_perm(cred, file, av); 3806 } 3807 3808 error: 3809 return rc; 3810 } 3811 3812 static int selinux_mmap_addr(unsigned long addr) 3813 { 3814 int rc = 0; 3815 3816 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3817 u32 sid = current_sid(); 3818 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3819 MEMPROTECT__MMAP_ZERO, NULL); 3820 } 3821 3822 return rc; 3823 } 3824 3825 static int selinux_mmap_file(struct file *file, 3826 unsigned long reqprot __always_unused, 3827 unsigned long prot, unsigned long flags) 3828 { 3829 struct common_audit_data ad; 3830 int rc; 3831 3832 if (file) { 3833 ad.type = LSM_AUDIT_DATA_FILE; 3834 ad.u.file = file; 3835 rc = inode_has_perm(current_cred(), file_inode(file), 3836 FILE__MAP, &ad); 3837 if (rc) 3838 return rc; 3839 } 3840 3841 return file_map_prot_check(file, prot, 3842 (flags & MAP_TYPE) == MAP_SHARED); 3843 } 3844 3845 static int selinux_file_mprotect(struct vm_area_struct *vma, 3846 unsigned long reqprot __always_unused, 3847 unsigned long prot) 3848 { 3849 const struct cred *cred = current_cred(); 3850 u32 sid = cred_sid(cred); 3851 3852 if (default_noexec && 3853 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3854 int rc = 0; 3855 /* 3856 * We don't use the vma_is_initial_heap() helper as it has 3857 * a history of problems and is currently broken on systems 3858 * where there is no heap, e.g. brk == start_brk. Before 3859 * replacing the conditional below with vma_is_initial_heap(), 3860 * or something similar, please ensure that the logic is the 3861 * same as what we have below or you have tested every possible 3862 * corner case you can think to test. 3863 */ 3864 if (vma->vm_start >= vma->vm_mm->start_brk && 3865 vma->vm_end <= vma->vm_mm->brk) { 3866 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3867 PROCESS__EXECHEAP, NULL); 3868 } else if (!vma->vm_file && (vma_is_initial_stack(vma) || 3869 vma_is_stack_for_current(vma))) { 3870 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3871 PROCESS__EXECSTACK, NULL); 3872 } else if (vma->vm_file && vma->anon_vma) { 3873 /* 3874 * We are making executable a file mapping that has 3875 * had some COW done. Since pages might have been 3876 * written, check ability to execute the possibly 3877 * modified content. This typically should only 3878 * occur for text relocations. 3879 */ 3880 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3881 } 3882 if (rc) 3883 return rc; 3884 } 3885 3886 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3887 } 3888 3889 static int selinux_file_lock(struct file *file, unsigned int cmd) 3890 { 3891 const struct cred *cred = current_cred(); 3892 3893 return file_has_perm(cred, file, FILE__LOCK); 3894 } 3895 3896 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3897 unsigned long arg) 3898 { 3899 const struct cred *cred = current_cred(); 3900 int err = 0; 3901 3902 switch (cmd) { 3903 case F_SETFL: 3904 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3905 err = file_has_perm(cred, file, FILE__WRITE); 3906 break; 3907 } 3908 fallthrough; 3909 case F_SETOWN: 3910 case F_SETSIG: 3911 case F_GETFL: 3912 case F_GETOWN: 3913 case F_GETSIG: 3914 case F_GETOWNER_UIDS: 3915 /* Just check FD__USE permission */ 3916 err = file_has_perm(cred, file, 0); 3917 break; 3918 case F_GETLK: 3919 case F_SETLK: 3920 case F_SETLKW: 3921 case F_OFD_GETLK: 3922 case F_OFD_SETLK: 3923 case F_OFD_SETLKW: 3924 #if BITS_PER_LONG == 32 3925 case F_GETLK64: 3926 case F_SETLK64: 3927 case F_SETLKW64: 3928 #endif 3929 err = file_has_perm(cred, file, FILE__LOCK); 3930 break; 3931 } 3932 3933 return err; 3934 } 3935 3936 static void selinux_file_set_fowner(struct file *file) 3937 { 3938 struct file_security_struct *fsec; 3939 3940 fsec = selinux_file(file); 3941 fsec->fown_sid = current_sid(); 3942 } 3943 3944 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3945 struct fown_struct *fown, int signum) 3946 { 3947 struct file *file; 3948 u32 sid = task_sid_obj(tsk); 3949 u32 perm; 3950 struct file_security_struct *fsec; 3951 3952 /* struct fown_struct is never outside the context of a struct file */ 3953 file = container_of(fown, struct file, f_owner); 3954 3955 fsec = selinux_file(file); 3956 3957 if (!signum) 3958 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3959 else 3960 perm = signal_to_av(signum); 3961 3962 return avc_has_perm(fsec->fown_sid, sid, 3963 SECCLASS_PROCESS, perm, NULL); 3964 } 3965 3966 static int selinux_file_receive(struct file *file) 3967 { 3968 const struct cred *cred = current_cred(); 3969 3970 return file_has_perm(cred, file, file_to_av(file)); 3971 } 3972 3973 static int selinux_file_open(struct file *file) 3974 { 3975 struct file_security_struct *fsec; 3976 struct inode_security_struct *isec; 3977 3978 fsec = selinux_file(file); 3979 isec = inode_security(file_inode(file)); 3980 /* 3981 * Save inode label and policy sequence number 3982 * at open-time so that selinux_file_permission 3983 * can determine whether revalidation is necessary. 3984 * Task label is already saved in the file security 3985 * struct as its SID. 3986 */ 3987 fsec->isid = isec->sid; 3988 fsec->pseqno = avc_policy_seqno(); 3989 /* 3990 * Since the inode label or policy seqno may have changed 3991 * between the selinux_inode_permission check and the saving 3992 * of state above, recheck that access is still permitted. 3993 * Otherwise, access might never be revalidated against the 3994 * new inode label or new policy. 3995 * This check is not redundant - do not remove. 3996 */ 3997 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3998 } 3999 4000 /* task security operations */ 4001 4002 static int selinux_task_alloc(struct task_struct *task, 4003 unsigned long clone_flags) 4004 { 4005 u32 sid = current_sid(); 4006 4007 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 4008 } 4009 4010 /* 4011 * prepare a new set of credentials for modification 4012 */ 4013 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 4014 gfp_t gfp) 4015 { 4016 const struct task_security_struct *old_tsec = selinux_cred(old); 4017 struct task_security_struct *tsec = selinux_cred(new); 4018 4019 *tsec = *old_tsec; 4020 return 0; 4021 } 4022 4023 /* 4024 * transfer the SELinux data to a blank set of creds 4025 */ 4026 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 4027 { 4028 const struct task_security_struct *old_tsec = selinux_cred(old); 4029 struct task_security_struct *tsec = selinux_cred(new); 4030 4031 *tsec = *old_tsec; 4032 } 4033 4034 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 4035 { 4036 *secid = cred_sid(c); 4037 } 4038 4039 /* 4040 * set the security data for a kernel service 4041 * - all the creation contexts are set to unlabelled 4042 */ 4043 static int selinux_kernel_act_as(struct cred *new, u32 secid) 4044 { 4045 struct task_security_struct *tsec = selinux_cred(new); 4046 u32 sid = current_sid(); 4047 int ret; 4048 4049 ret = avc_has_perm(sid, secid, 4050 SECCLASS_KERNEL_SERVICE, 4051 KERNEL_SERVICE__USE_AS_OVERRIDE, 4052 NULL); 4053 if (ret == 0) { 4054 tsec->sid = secid; 4055 tsec->create_sid = 0; 4056 tsec->keycreate_sid = 0; 4057 tsec->sockcreate_sid = 0; 4058 } 4059 return ret; 4060 } 4061 4062 /* 4063 * set the file creation context in a security record to the same as the 4064 * objective context of the specified inode 4065 */ 4066 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4067 { 4068 struct inode_security_struct *isec = inode_security(inode); 4069 struct task_security_struct *tsec = selinux_cred(new); 4070 u32 sid = current_sid(); 4071 int ret; 4072 4073 ret = avc_has_perm(sid, isec->sid, 4074 SECCLASS_KERNEL_SERVICE, 4075 KERNEL_SERVICE__CREATE_FILES_AS, 4076 NULL); 4077 4078 if (ret == 0) 4079 tsec->create_sid = isec->sid; 4080 return ret; 4081 } 4082 4083 static int selinux_kernel_module_request(char *kmod_name) 4084 { 4085 struct common_audit_data ad; 4086 4087 ad.type = LSM_AUDIT_DATA_KMOD; 4088 ad.u.kmod_name = kmod_name; 4089 4090 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4091 SYSTEM__MODULE_REQUEST, &ad); 4092 } 4093 4094 static int selinux_kernel_module_from_file(struct file *file) 4095 { 4096 struct common_audit_data ad; 4097 struct inode_security_struct *isec; 4098 struct file_security_struct *fsec; 4099 u32 sid = current_sid(); 4100 int rc; 4101 4102 /* init_module */ 4103 if (file == NULL) 4104 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 4105 SYSTEM__MODULE_LOAD, NULL); 4106 4107 /* finit_module */ 4108 4109 ad.type = LSM_AUDIT_DATA_FILE; 4110 ad.u.file = file; 4111 4112 fsec = selinux_file(file); 4113 if (sid != fsec->sid) { 4114 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4115 if (rc) 4116 return rc; 4117 } 4118 4119 isec = inode_security(file_inode(file)); 4120 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 4121 SYSTEM__MODULE_LOAD, &ad); 4122 } 4123 4124 static int selinux_kernel_read_file(struct file *file, 4125 enum kernel_read_file_id id, 4126 bool contents) 4127 { 4128 int rc = 0; 4129 4130 switch (id) { 4131 case READING_MODULE: 4132 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4133 break; 4134 default: 4135 break; 4136 } 4137 4138 return rc; 4139 } 4140 4141 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4142 { 4143 int rc = 0; 4144 4145 switch (id) { 4146 case LOADING_MODULE: 4147 rc = selinux_kernel_module_from_file(NULL); 4148 break; 4149 default: 4150 break; 4151 } 4152 4153 return rc; 4154 } 4155 4156 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4157 { 4158 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4159 PROCESS__SETPGID, NULL); 4160 } 4161 4162 static int selinux_task_getpgid(struct task_struct *p) 4163 { 4164 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4165 PROCESS__GETPGID, NULL); 4166 } 4167 4168 static int selinux_task_getsid(struct task_struct *p) 4169 { 4170 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4171 PROCESS__GETSESSION, NULL); 4172 } 4173 4174 static void selinux_current_getsecid_subj(u32 *secid) 4175 { 4176 *secid = current_sid(); 4177 } 4178 4179 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) 4180 { 4181 *secid = task_sid_obj(p); 4182 } 4183 4184 static int selinux_task_setnice(struct task_struct *p, int nice) 4185 { 4186 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4187 PROCESS__SETSCHED, NULL); 4188 } 4189 4190 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4191 { 4192 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4193 PROCESS__SETSCHED, NULL); 4194 } 4195 4196 static int selinux_task_getioprio(struct task_struct *p) 4197 { 4198 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4199 PROCESS__GETSCHED, NULL); 4200 } 4201 4202 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4203 unsigned int flags) 4204 { 4205 u32 av = 0; 4206 4207 if (!flags) 4208 return 0; 4209 if (flags & LSM_PRLIMIT_WRITE) 4210 av |= PROCESS__SETRLIMIT; 4211 if (flags & LSM_PRLIMIT_READ) 4212 av |= PROCESS__GETRLIMIT; 4213 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4214 SECCLASS_PROCESS, av, NULL); 4215 } 4216 4217 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4218 struct rlimit *new_rlim) 4219 { 4220 struct rlimit *old_rlim = p->signal->rlim + resource; 4221 4222 /* Control the ability to change the hard limit (whether 4223 lowering or raising it), so that the hard limit can 4224 later be used as a safe reset point for the soft limit 4225 upon context transitions. See selinux_bprm_committing_creds. */ 4226 if (old_rlim->rlim_max != new_rlim->rlim_max) 4227 return avc_has_perm(current_sid(), task_sid_obj(p), 4228 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4229 4230 return 0; 4231 } 4232 4233 static int selinux_task_setscheduler(struct task_struct *p) 4234 { 4235 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4236 PROCESS__SETSCHED, NULL); 4237 } 4238 4239 static int selinux_task_getscheduler(struct task_struct *p) 4240 { 4241 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4242 PROCESS__GETSCHED, NULL); 4243 } 4244 4245 static int selinux_task_movememory(struct task_struct *p) 4246 { 4247 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4248 PROCESS__SETSCHED, NULL); 4249 } 4250 4251 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4252 int sig, const struct cred *cred) 4253 { 4254 u32 secid; 4255 u32 perm; 4256 4257 if (!sig) 4258 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4259 else 4260 perm = signal_to_av(sig); 4261 if (!cred) 4262 secid = current_sid(); 4263 else 4264 secid = cred_sid(cred); 4265 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4266 } 4267 4268 static void selinux_task_to_inode(struct task_struct *p, 4269 struct inode *inode) 4270 { 4271 struct inode_security_struct *isec = selinux_inode(inode); 4272 u32 sid = task_sid_obj(p); 4273 4274 spin_lock(&isec->lock); 4275 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4276 isec->sid = sid; 4277 isec->initialized = LABEL_INITIALIZED; 4278 spin_unlock(&isec->lock); 4279 } 4280 4281 static int selinux_userns_create(const struct cred *cred) 4282 { 4283 u32 sid = current_sid(); 4284 4285 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4286 USER_NAMESPACE__CREATE, NULL); 4287 } 4288 4289 /* Returns error only if unable to parse addresses */ 4290 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4291 struct common_audit_data *ad, u8 *proto) 4292 { 4293 int offset, ihlen, ret = -EINVAL; 4294 struct iphdr _iph, *ih; 4295 4296 offset = skb_network_offset(skb); 4297 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4298 if (ih == NULL) 4299 goto out; 4300 4301 ihlen = ih->ihl * 4; 4302 if (ihlen < sizeof(_iph)) 4303 goto out; 4304 4305 ad->u.net->v4info.saddr = ih->saddr; 4306 ad->u.net->v4info.daddr = ih->daddr; 4307 ret = 0; 4308 4309 if (proto) 4310 *proto = ih->protocol; 4311 4312 switch (ih->protocol) { 4313 case IPPROTO_TCP: { 4314 struct tcphdr _tcph, *th; 4315 4316 if (ntohs(ih->frag_off) & IP_OFFSET) 4317 break; 4318 4319 offset += ihlen; 4320 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4321 if (th == NULL) 4322 break; 4323 4324 ad->u.net->sport = th->source; 4325 ad->u.net->dport = th->dest; 4326 break; 4327 } 4328 4329 case IPPROTO_UDP: { 4330 struct udphdr _udph, *uh; 4331 4332 if (ntohs(ih->frag_off) & IP_OFFSET) 4333 break; 4334 4335 offset += ihlen; 4336 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4337 if (uh == NULL) 4338 break; 4339 4340 ad->u.net->sport = uh->source; 4341 ad->u.net->dport = uh->dest; 4342 break; 4343 } 4344 4345 case IPPROTO_DCCP: { 4346 struct dccp_hdr _dccph, *dh; 4347 4348 if (ntohs(ih->frag_off) & IP_OFFSET) 4349 break; 4350 4351 offset += ihlen; 4352 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4353 if (dh == NULL) 4354 break; 4355 4356 ad->u.net->sport = dh->dccph_sport; 4357 ad->u.net->dport = dh->dccph_dport; 4358 break; 4359 } 4360 4361 #if IS_ENABLED(CONFIG_IP_SCTP) 4362 case IPPROTO_SCTP: { 4363 struct sctphdr _sctph, *sh; 4364 4365 if (ntohs(ih->frag_off) & IP_OFFSET) 4366 break; 4367 4368 offset += ihlen; 4369 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4370 if (sh == NULL) 4371 break; 4372 4373 ad->u.net->sport = sh->source; 4374 ad->u.net->dport = sh->dest; 4375 break; 4376 } 4377 #endif 4378 default: 4379 break; 4380 } 4381 out: 4382 return ret; 4383 } 4384 4385 #if IS_ENABLED(CONFIG_IPV6) 4386 4387 /* Returns error only if unable to parse addresses */ 4388 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4389 struct common_audit_data *ad, u8 *proto) 4390 { 4391 u8 nexthdr; 4392 int ret = -EINVAL, offset; 4393 struct ipv6hdr _ipv6h, *ip6; 4394 __be16 frag_off; 4395 4396 offset = skb_network_offset(skb); 4397 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4398 if (ip6 == NULL) 4399 goto out; 4400 4401 ad->u.net->v6info.saddr = ip6->saddr; 4402 ad->u.net->v6info.daddr = ip6->daddr; 4403 ret = 0; 4404 4405 nexthdr = ip6->nexthdr; 4406 offset += sizeof(_ipv6h); 4407 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4408 if (offset < 0) 4409 goto out; 4410 4411 if (proto) 4412 *proto = nexthdr; 4413 4414 switch (nexthdr) { 4415 case IPPROTO_TCP: { 4416 struct tcphdr _tcph, *th; 4417 4418 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4419 if (th == NULL) 4420 break; 4421 4422 ad->u.net->sport = th->source; 4423 ad->u.net->dport = th->dest; 4424 break; 4425 } 4426 4427 case IPPROTO_UDP: { 4428 struct udphdr _udph, *uh; 4429 4430 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4431 if (uh == NULL) 4432 break; 4433 4434 ad->u.net->sport = uh->source; 4435 ad->u.net->dport = uh->dest; 4436 break; 4437 } 4438 4439 case IPPROTO_DCCP: { 4440 struct dccp_hdr _dccph, *dh; 4441 4442 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4443 if (dh == NULL) 4444 break; 4445 4446 ad->u.net->sport = dh->dccph_sport; 4447 ad->u.net->dport = dh->dccph_dport; 4448 break; 4449 } 4450 4451 #if IS_ENABLED(CONFIG_IP_SCTP) 4452 case IPPROTO_SCTP: { 4453 struct sctphdr _sctph, *sh; 4454 4455 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4456 if (sh == NULL) 4457 break; 4458 4459 ad->u.net->sport = sh->source; 4460 ad->u.net->dport = sh->dest; 4461 break; 4462 } 4463 #endif 4464 /* includes fragments */ 4465 default: 4466 break; 4467 } 4468 out: 4469 return ret; 4470 } 4471 4472 #endif /* IPV6 */ 4473 4474 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4475 char **_addrp, int src, u8 *proto) 4476 { 4477 char *addrp; 4478 int ret; 4479 4480 switch (ad->u.net->family) { 4481 case PF_INET: 4482 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4483 if (ret) 4484 goto parse_error; 4485 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4486 &ad->u.net->v4info.daddr); 4487 goto okay; 4488 4489 #if IS_ENABLED(CONFIG_IPV6) 4490 case PF_INET6: 4491 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4492 if (ret) 4493 goto parse_error; 4494 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4495 &ad->u.net->v6info.daddr); 4496 goto okay; 4497 #endif /* IPV6 */ 4498 default: 4499 addrp = NULL; 4500 goto okay; 4501 } 4502 4503 parse_error: 4504 pr_warn( 4505 "SELinux: failure in selinux_parse_skb()," 4506 " unable to parse packet\n"); 4507 return ret; 4508 4509 okay: 4510 if (_addrp) 4511 *_addrp = addrp; 4512 return 0; 4513 } 4514 4515 /** 4516 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4517 * @skb: the packet 4518 * @family: protocol family 4519 * @sid: the packet's peer label SID 4520 * 4521 * Description: 4522 * Check the various different forms of network peer labeling and determine 4523 * the peer label/SID for the packet; most of the magic actually occurs in 4524 * the security server function security_net_peersid_cmp(). The function 4525 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4526 * or -EACCES if @sid is invalid due to inconsistencies with the different 4527 * peer labels. 4528 * 4529 */ 4530 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4531 { 4532 int err; 4533 u32 xfrm_sid; 4534 u32 nlbl_sid; 4535 u32 nlbl_type; 4536 4537 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4538 if (unlikely(err)) 4539 return -EACCES; 4540 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4541 if (unlikely(err)) 4542 return -EACCES; 4543 4544 err = security_net_peersid_resolve(nlbl_sid, 4545 nlbl_type, xfrm_sid, sid); 4546 if (unlikely(err)) { 4547 pr_warn( 4548 "SELinux: failure in selinux_skb_peerlbl_sid()," 4549 " unable to determine packet's peer label\n"); 4550 return -EACCES; 4551 } 4552 4553 return 0; 4554 } 4555 4556 /** 4557 * selinux_conn_sid - Determine the child socket label for a connection 4558 * @sk_sid: the parent socket's SID 4559 * @skb_sid: the packet's SID 4560 * @conn_sid: the resulting connection SID 4561 * 4562 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4563 * combined with the MLS information from @skb_sid in order to create 4564 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4565 * of @sk_sid. Returns zero on success, negative values on failure. 4566 * 4567 */ 4568 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4569 { 4570 int err = 0; 4571 4572 if (skb_sid != SECSID_NULL) 4573 err = security_sid_mls_copy(sk_sid, skb_sid, 4574 conn_sid); 4575 else 4576 *conn_sid = sk_sid; 4577 4578 return err; 4579 } 4580 4581 /* socket security operations */ 4582 4583 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4584 u16 secclass, u32 *socksid) 4585 { 4586 if (tsec->sockcreate_sid > SECSID_NULL) { 4587 *socksid = tsec->sockcreate_sid; 4588 return 0; 4589 } 4590 4591 return security_transition_sid(tsec->sid, tsec->sid, 4592 secclass, NULL, socksid); 4593 } 4594 4595 static int sock_has_perm(struct sock *sk, u32 perms) 4596 { 4597 struct sk_security_struct *sksec = sk->sk_security; 4598 struct common_audit_data ad; 4599 struct lsm_network_audit net; 4600 4601 if (sksec->sid == SECINITSID_KERNEL) 4602 return 0; 4603 4604 /* 4605 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that 4606 * inherited the kernel context from early boot used to be skipped 4607 * here, so preserve that behavior unless the capability is set. 4608 * 4609 * By setting the capability the policy signals that it is ready 4610 * for this quirk to be fixed. Note that sockets created by a kernel 4611 * thread or a usermode helper executed without a transition will 4612 * still be skipped in this check regardless of the policycap 4613 * setting. 4614 */ 4615 if (!selinux_policycap_userspace_initial_context() && 4616 sksec->sid == SECINITSID_INIT) 4617 return 0; 4618 4619 ad_net_init_from_sk(&ad, &net, sk); 4620 4621 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4622 &ad); 4623 } 4624 4625 static int selinux_socket_create(int family, int type, 4626 int protocol, int kern) 4627 { 4628 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4629 u32 newsid; 4630 u16 secclass; 4631 int rc; 4632 4633 if (kern) 4634 return 0; 4635 4636 secclass = socket_type_to_security_class(family, type, protocol); 4637 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4638 if (rc) 4639 return rc; 4640 4641 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4642 } 4643 4644 static int selinux_socket_post_create(struct socket *sock, int family, 4645 int type, int protocol, int kern) 4646 { 4647 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4648 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4649 struct sk_security_struct *sksec; 4650 u16 sclass = socket_type_to_security_class(family, type, protocol); 4651 u32 sid = SECINITSID_KERNEL; 4652 int err = 0; 4653 4654 if (!kern) { 4655 err = socket_sockcreate_sid(tsec, sclass, &sid); 4656 if (err) 4657 return err; 4658 } 4659 4660 isec->sclass = sclass; 4661 isec->sid = sid; 4662 isec->initialized = LABEL_INITIALIZED; 4663 4664 if (sock->sk) { 4665 sksec = sock->sk->sk_security; 4666 sksec->sclass = sclass; 4667 sksec->sid = sid; 4668 /* Allows detection of the first association on this socket */ 4669 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4670 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4671 4672 err = selinux_netlbl_socket_post_create(sock->sk, family); 4673 } 4674 4675 return err; 4676 } 4677 4678 static int selinux_socket_socketpair(struct socket *socka, 4679 struct socket *sockb) 4680 { 4681 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4682 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4683 4684 sksec_a->peer_sid = sksec_b->sid; 4685 sksec_b->peer_sid = sksec_a->sid; 4686 4687 return 0; 4688 } 4689 4690 /* Range of port numbers used to automatically bind. 4691 Need to determine whether we should perform a name_bind 4692 permission check between the socket and the port number. */ 4693 4694 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4695 { 4696 struct sock *sk = sock->sk; 4697 struct sk_security_struct *sksec = sk->sk_security; 4698 u16 family; 4699 int err; 4700 4701 err = sock_has_perm(sk, SOCKET__BIND); 4702 if (err) 4703 goto out; 4704 4705 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4706 family = sk->sk_family; 4707 if (family == PF_INET || family == PF_INET6) { 4708 char *addrp; 4709 struct common_audit_data ad; 4710 struct lsm_network_audit net = {0,}; 4711 struct sockaddr_in *addr4 = NULL; 4712 struct sockaddr_in6 *addr6 = NULL; 4713 u16 family_sa; 4714 unsigned short snum; 4715 u32 sid, node_perm; 4716 4717 /* 4718 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4719 * that validates multiple binding addresses. Because of this 4720 * need to check address->sa_family as it is possible to have 4721 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4722 */ 4723 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4724 return -EINVAL; 4725 family_sa = address->sa_family; 4726 switch (family_sa) { 4727 case AF_UNSPEC: 4728 case AF_INET: 4729 if (addrlen < sizeof(struct sockaddr_in)) 4730 return -EINVAL; 4731 addr4 = (struct sockaddr_in *)address; 4732 if (family_sa == AF_UNSPEC) { 4733 if (family == PF_INET6) { 4734 /* Length check from inet6_bind_sk() */ 4735 if (addrlen < SIN6_LEN_RFC2133) 4736 return -EINVAL; 4737 /* Family check from __inet6_bind() */ 4738 goto err_af; 4739 } 4740 /* see __inet_bind(), we only want to allow 4741 * AF_UNSPEC if the address is INADDR_ANY 4742 */ 4743 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4744 goto err_af; 4745 family_sa = AF_INET; 4746 } 4747 snum = ntohs(addr4->sin_port); 4748 addrp = (char *)&addr4->sin_addr.s_addr; 4749 break; 4750 case AF_INET6: 4751 if (addrlen < SIN6_LEN_RFC2133) 4752 return -EINVAL; 4753 addr6 = (struct sockaddr_in6 *)address; 4754 snum = ntohs(addr6->sin6_port); 4755 addrp = (char *)&addr6->sin6_addr.s6_addr; 4756 break; 4757 default: 4758 goto err_af; 4759 } 4760 4761 ad.type = LSM_AUDIT_DATA_NET; 4762 ad.u.net = &net; 4763 ad.u.net->sport = htons(snum); 4764 ad.u.net->family = family_sa; 4765 4766 if (snum) { 4767 int low, high; 4768 4769 inet_get_local_port_range(sock_net(sk), &low, &high); 4770 4771 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4772 snum < low || snum > high) { 4773 err = sel_netport_sid(sk->sk_protocol, 4774 snum, &sid); 4775 if (err) 4776 goto out; 4777 err = avc_has_perm(sksec->sid, sid, 4778 sksec->sclass, 4779 SOCKET__NAME_BIND, &ad); 4780 if (err) 4781 goto out; 4782 } 4783 } 4784 4785 switch (sksec->sclass) { 4786 case SECCLASS_TCP_SOCKET: 4787 node_perm = TCP_SOCKET__NODE_BIND; 4788 break; 4789 4790 case SECCLASS_UDP_SOCKET: 4791 node_perm = UDP_SOCKET__NODE_BIND; 4792 break; 4793 4794 case SECCLASS_DCCP_SOCKET: 4795 node_perm = DCCP_SOCKET__NODE_BIND; 4796 break; 4797 4798 case SECCLASS_SCTP_SOCKET: 4799 node_perm = SCTP_SOCKET__NODE_BIND; 4800 break; 4801 4802 default: 4803 node_perm = RAWIP_SOCKET__NODE_BIND; 4804 break; 4805 } 4806 4807 err = sel_netnode_sid(addrp, family_sa, &sid); 4808 if (err) 4809 goto out; 4810 4811 if (family_sa == AF_INET) 4812 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4813 else 4814 ad.u.net->v6info.saddr = addr6->sin6_addr; 4815 4816 err = avc_has_perm(sksec->sid, sid, 4817 sksec->sclass, node_perm, &ad); 4818 if (err) 4819 goto out; 4820 } 4821 out: 4822 return err; 4823 err_af: 4824 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4825 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4826 return -EINVAL; 4827 return -EAFNOSUPPORT; 4828 } 4829 4830 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4831 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4832 */ 4833 static int selinux_socket_connect_helper(struct socket *sock, 4834 struct sockaddr *address, int addrlen) 4835 { 4836 struct sock *sk = sock->sk; 4837 struct sk_security_struct *sksec = sk->sk_security; 4838 int err; 4839 4840 err = sock_has_perm(sk, SOCKET__CONNECT); 4841 if (err) 4842 return err; 4843 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4844 return -EINVAL; 4845 4846 /* connect(AF_UNSPEC) has special handling, as it is a documented 4847 * way to disconnect the socket 4848 */ 4849 if (address->sa_family == AF_UNSPEC) 4850 return 0; 4851 4852 /* 4853 * If a TCP, DCCP or SCTP socket, check name_connect permission 4854 * for the port. 4855 */ 4856 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4857 sksec->sclass == SECCLASS_DCCP_SOCKET || 4858 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4859 struct common_audit_data ad; 4860 struct lsm_network_audit net = {0,}; 4861 struct sockaddr_in *addr4 = NULL; 4862 struct sockaddr_in6 *addr6 = NULL; 4863 unsigned short snum; 4864 u32 sid, perm; 4865 4866 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4867 * that validates multiple connect addresses. Because of this 4868 * need to check address->sa_family as it is possible to have 4869 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4870 */ 4871 switch (address->sa_family) { 4872 case AF_INET: 4873 addr4 = (struct sockaddr_in *)address; 4874 if (addrlen < sizeof(struct sockaddr_in)) 4875 return -EINVAL; 4876 snum = ntohs(addr4->sin_port); 4877 break; 4878 case AF_INET6: 4879 addr6 = (struct sockaddr_in6 *)address; 4880 if (addrlen < SIN6_LEN_RFC2133) 4881 return -EINVAL; 4882 snum = ntohs(addr6->sin6_port); 4883 break; 4884 default: 4885 /* Note that SCTP services expect -EINVAL, whereas 4886 * others expect -EAFNOSUPPORT. 4887 */ 4888 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4889 return -EINVAL; 4890 else 4891 return -EAFNOSUPPORT; 4892 } 4893 4894 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4895 if (err) 4896 return err; 4897 4898 switch (sksec->sclass) { 4899 case SECCLASS_TCP_SOCKET: 4900 perm = TCP_SOCKET__NAME_CONNECT; 4901 break; 4902 case SECCLASS_DCCP_SOCKET: 4903 perm = DCCP_SOCKET__NAME_CONNECT; 4904 break; 4905 case SECCLASS_SCTP_SOCKET: 4906 perm = SCTP_SOCKET__NAME_CONNECT; 4907 break; 4908 } 4909 4910 ad.type = LSM_AUDIT_DATA_NET; 4911 ad.u.net = &net; 4912 ad.u.net->dport = htons(snum); 4913 ad.u.net->family = address->sa_family; 4914 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4915 if (err) 4916 return err; 4917 } 4918 4919 return 0; 4920 } 4921 4922 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4923 static int selinux_socket_connect(struct socket *sock, 4924 struct sockaddr *address, int addrlen) 4925 { 4926 int err; 4927 struct sock *sk = sock->sk; 4928 4929 err = selinux_socket_connect_helper(sock, address, addrlen); 4930 if (err) 4931 return err; 4932 4933 return selinux_netlbl_socket_connect(sk, address); 4934 } 4935 4936 static int selinux_socket_listen(struct socket *sock, int backlog) 4937 { 4938 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4939 } 4940 4941 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4942 { 4943 int err; 4944 struct inode_security_struct *isec; 4945 struct inode_security_struct *newisec; 4946 u16 sclass; 4947 u32 sid; 4948 4949 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4950 if (err) 4951 return err; 4952 4953 isec = inode_security_novalidate(SOCK_INODE(sock)); 4954 spin_lock(&isec->lock); 4955 sclass = isec->sclass; 4956 sid = isec->sid; 4957 spin_unlock(&isec->lock); 4958 4959 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4960 newisec->sclass = sclass; 4961 newisec->sid = sid; 4962 newisec->initialized = LABEL_INITIALIZED; 4963 4964 return 0; 4965 } 4966 4967 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4968 int size) 4969 { 4970 return sock_has_perm(sock->sk, SOCKET__WRITE); 4971 } 4972 4973 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4974 int size, int flags) 4975 { 4976 return sock_has_perm(sock->sk, SOCKET__READ); 4977 } 4978 4979 static int selinux_socket_getsockname(struct socket *sock) 4980 { 4981 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4982 } 4983 4984 static int selinux_socket_getpeername(struct socket *sock) 4985 { 4986 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4987 } 4988 4989 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4990 { 4991 int err; 4992 4993 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4994 if (err) 4995 return err; 4996 4997 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4998 } 4999 5000 static int selinux_socket_getsockopt(struct socket *sock, int level, 5001 int optname) 5002 { 5003 return sock_has_perm(sock->sk, SOCKET__GETOPT); 5004 } 5005 5006 static int selinux_socket_shutdown(struct socket *sock, int how) 5007 { 5008 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 5009 } 5010 5011 static int selinux_socket_unix_stream_connect(struct sock *sock, 5012 struct sock *other, 5013 struct sock *newsk) 5014 { 5015 struct sk_security_struct *sksec_sock = sock->sk_security; 5016 struct sk_security_struct *sksec_other = other->sk_security; 5017 struct sk_security_struct *sksec_new = newsk->sk_security; 5018 struct common_audit_data ad; 5019 struct lsm_network_audit net; 5020 int err; 5021 5022 ad_net_init_from_sk(&ad, &net, other); 5023 5024 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 5025 sksec_other->sclass, 5026 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 5027 if (err) 5028 return err; 5029 5030 /* server child socket */ 5031 sksec_new->peer_sid = sksec_sock->sid; 5032 err = security_sid_mls_copy(sksec_other->sid, 5033 sksec_sock->sid, &sksec_new->sid); 5034 if (err) 5035 return err; 5036 5037 /* connecting socket */ 5038 sksec_sock->peer_sid = sksec_new->sid; 5039 5040 return 0; 5041 } 5042 5043 static int selinux_socket_unix_may_send(struct socket *sock, 5044 struct socket *other) 5045 { 5046 struct sk_security_struct *ssec = sock->sk->sk_security; 5047 struct sk_security_struct *osec = other->sk->sk_security; 5048 struct common_audit_data ad; 5049 struct lsm_network_audit net; 5050 5051 ad_net_init_from_sk(&ad, &net, other->sk); 5052 5053 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 5054 &ad); 5055 } 5056 5057 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 5058 char *addrp, u16 family, u32 peer_sid, 5059 struct common_audit_data *ad) 5060 { 5061 int err; 5062 u32 if_sid; 5063 u32 node_sid; 5064 5065 err = sel_netif_sid(ns, ifindex, &if_sid); 5066 if (err) 5067 return err; 5068 err = avc_has_perm(peer_sid, if_sid, 5069 SECCLASS_NETIF, NETIF__INGRESS, ad); 5070 if (err) 5071 return err; 5072 5073 err = sel_netnode_sid(addrp, family, &node_sid); 5074 if (err) 5075 return err; 5076 return avc_has_perm(peer_sid, node_sid, 5077 SECCLASS_NODE, NODE__RECVFROM, ad); 5078 } 5079 5080 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5081 u16 family) 5082 { 5083 int err = 0; 5084 struct sk_security_struct *sksec = sk->sk_security; 5085 u32 sk_sid = sksec->sid; 5086 struct common_audit_data ad; 5087 struct lsm_network_audit net; 5088 char *addrp; 5089 5090 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5091 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5092 if (err) 5093 return err; 5094 5095 if (selinux_secmark_enabled()) { 5096 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5097 PACKET__RECV, &ad); 5098 if (err) 5099 return err; 5100 } 5101 5102 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5103 if (err) 5104 return err; 5105 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5106 5107 return err; 5108 } 5109 5110 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5111 { 5112 int err, peerlbl_active, secmark_active; 5113 struct sk_security_struct *sksec = sk->sk_security; 5114 u16 family = sk->sk_family; 5115 u32 sk_sid = sksec->sid; 5116 struct common_audit_data ad; 5117 struct lsm_network_audit net; 5118 char *addrp; 5119 5120 if (family != PF_INET && family != PF_INET6) 5121 return 0; 5122 5123 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5124 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5125 family = PF_INET; 5126 5127 /* If any sort of compatibility mode is enabled then handoff processing 5128 * to the selinux_sock_rcv_skb_compat() function to deal with the 5129 * special handling. We do this in an attempt to keep this function 5130 * as fast and as clean as possible. */ 5131 if (!selinux_policycap_netpeer()) 5132 return selinux_sock_rcv_skb_compat(sk, skb, family); 5133 5134 secmark_active = selinux_secmark_enabled(); 5135 peerlbl_active = selinux_peerlbl_enabled(); 5136 if (!secmark_active && !peerlbl_active) 5137 return 0; 5138 5139 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5140 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5141 if (err) 5142 return err; 5143 5144 if (peerlbl_active) { 5145 u32 peer_sid; 5146 5147 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5148 if (err) 5149 return err; 5150 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5151 addrp, family, peer_sid, &ad); 5152 if (err) { 5153 selinux_netlbl_err(skb, family, err, 0); 5154 return err; 5155 } 5156 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5157 PEER__RECV, &ad); 5158 if (err) { 5159 selinux_netlbl_err(skb, family, err, 0); 5160 return err; 5161 } 5162 } 5163 5164 if (secmark_active) { 5165 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5166 PACKET__RECV, &ad); 5167 if (err) 5168 return err; 5169 } 5170 5171 return err; 5172 } 5173 5174 static int selinux_socket_getpeersec_stream(struct socket *sock, 5175 sockptr_t optval, sockptr_t optlen, 5176 unsigned int len) 5177 { 5178 int err = 0; 5179 char *scontext = NULL; 5180 u32 scontext_len; 5181 struct sk_security_struct *sksec = sock->sk->sk_security; 5182 u32 peer_sid = SECSID_NULL; 5183 5184 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5185 sksec->sclass == SECCLASS_TCP_SOCKET || 5186 sksec->sclass == SECCLASS_SCTP_SOCKET) 5187 peer_sid = sksec->peer_sid; 5188 if (peer_sid == SECSID_NULL) 5189 return -ENOPROTOOPT; 5190 5191 err = security_sid_to_context(peer_sid, &scontext, 5192 &scontext_len); 5193 if (err) 5194 return err; 5195 if (scontext_len > len) { 5196 err = -ERANGE; 5197 goto out_len; 5198 } 5199 5200 if (copy_to_sockptr(optval, scontext, scontext_len)) 5201 err = -EFAULT; 5202 out_len: 5203 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5204 err = -EFAULT; 5205 kfree(scontext); 5206 return err; 5207 } 5208 5209 static int selinux_socket_getpeersec_dgram(struct socket *sock, 5210 struct sk_buff *skb, u32 *secid) 5211 { 5212 u32 peer_secid = SECSID_NULL; 5213 u16 family; 5214 5215 if (skb && skb->protocol == htons(ETH_P_IP)) 5216 family = PF_INET; 5217 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5218 family = PF_INET6; 5219 else if (sock) 5220 family = sock->sk->sk_family; 5221 else { 5222 *secid = SECSID_NULL; 5223 return -EINVAL; 5224 } 5225 5226 if (sock && family == PF_UNIX) { 5227 struct inode_security_struct *isec; 5228 isec = inode_security_novalidate(SOCK_INODE(sock)); 5229 peer_secid = isec->sid; 5230 } else if (skb) 5231 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5232 5233 *secid = peer_secid; 5234 if (peer_secid == SECSID_NULL) 5235 return -ENOPROTOOPT; 5236 return 0; 5237 } 5238 5239 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5240 { 5241 struct sk_security_struct *sksec; 5242 5243 sksec = kzalloc(sizeof(*sksec), priority); 5244 if (!sksec) 5245 return -ENOMEM; 5246 5247 sksec->peer_sid = SECINITSID_UNLABELED; 5248 sksec->sid = SECINITSID_UNLABELED; 5249 sksec->sclass = SECCLASS_SOCKET; 5250 selinux_netlbl_sk_security_reset(sksec); 5251 sk->sk_security = sksec; 5252 5253 return 0; 5254 } 5255 5256 static void selinux_sk_free_security(struct sock *sk) 5257 { 5258 struct sk_security_struct *sksec = sk->sk_security; 5259 5260 sk->sk_security = NULL; 5261 selinux_netlbl_sk_security_free(sksec); 5262 kfree(sksec); 5263 } 5264 5265 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5266 { 5267 struct sk_security_struct *sksec = sk->sk_security; 5268 struct sk_security_struct *newsksec = newsk->sk_security; 5269 5270 newsksec->sid = sksec->sid; 5271 newsksec->peer_sid = sksec->peer_sid; 5272 newsksec->sclass = sksec->sclass; 5273 5274 selinux_netlbl_sk_security_reset(newsksec); 5275 } 5276 5277 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5278 { 5279 if (!sk) 5280 *secid = SECINITSID_ANY_SOCKET; 5281 else { 5282 const struct sk_security_struct *sksec = sk->sk_security; 5283 5284 *secid = sksec->sid; 5285 } 5286 } 5287 5288 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5289 { 5290 struct inode_security_struct *isec = 5291 inode_security_novalidate(SOCK_INODE(parent)); 5292 struct sk_security_struct *sksec = sk->sk_security; 5293 5294 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5295 sk->sk_family == PF_UNIX) 5296 isec->sid = sksec->sid; 5297 sksec->sclass = isec->sclass; 5298 } 5299 5300 /* 5301 * Determines peer_secid for the asoc and updates socket's peer label 5302 * if it's the first association on the socket. 5303 */ 5304 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5305 struct sk_buff *skb) 5306 { 5307 struct sock *sk = asoc->base.sk; 5308 u16 family = sk->sk_family; 5309 struct sk_security_struct *sksec = sk->sk_security; 5310 struct common_audit_data ad; 5311 struct lsm_network_audit net; 5312 int err; 5313 5314 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5315 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5316 family = PF_INET; 5317 5318 if (selinux_peerlbl_enabled()) { 5319 asoc->peer_secid = SECSID_NULL; 5320 5321 /* This will return peer_sid = SECSID_NULL if there are 5322 * no peer labels, see security_net_peersid_resolve(). 5323 */ 5324 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5325 if (err) 5326 return err; 5327 5328 if (asoc->peer_secid == SECSID_NULL) 5329 asoc->peer_secid = SECINITSID_UNLABELED; 5330 } else { 5331 asoc->peer_secid = SECINITSID_UNLABELED; 5332 } 5333 5334 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5335 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5336 5337 /* Here as first association on socket. As the peer SID 5338 * was allowed by peer recv (and the netif/node checks), 5339 * then it is approved by policy and used as the primary 5340 * peer SID for getpeercon(3). 5341 */ 5342 sksec->peer_sid = asoc->peer_secid; 5343 } else if (sksec->peer_sid != asoc->peer_secid) { 5344 /* Other association peer SIDs are checked to enforce 5345 * consistency among the peer SIDs. 5346 */ 5347 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5348 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5349 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5350 &ad); 5351 if (err) 5352 return err; 5353 } 5354 return 0; 5355 } 5356 5357 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5358 * happens on an incoming connect(2), sctp_connectx(3) or 5359 * sctp_sendmsg(3) (with no association already present). 5360 */ 5361 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5362 struct sk_buff *skb) 5363 { 5364 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5365 u32 conn_sid; 5366 int err; 5367 5368 if (!selinux_policycap_extsockclass()) 5369 return 0; 5370 5371 err = selinux_sctp_process_new_assoc(asoc, skb); 5372 if (err) 5373 return err; 5374 5375 /* Compute the MLS component for the connection and store 5376 * the information in asoc. This will be used by SCTP TCP type 5377 * sockets and peeled off connections as they cause a new 5378 * socket to be generated. selinux_sctp_sk_clone() will then 5379 * plug this into the new socket. 5380 */ 5381 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5382 if (err) 5383 return err; 5384 5385 asoc->secid = conn_sid; 5386 5387 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5388 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5389 } 5390 5391 /* Called when SCTP receives a COOKIE ACK chunk as the final 5392 * response to an association request (initited by us). 5393 */ 5394 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5395 struct sk_buff *skb) 5396 { 5397 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5398 5399 if (!selinux_policycap_extsockclass()) 5400 return 0; 5401 5402 /* Inherit secid from the parent socket - this will be picked up 5403 * by selinux_sctp_sk_clone() if the association gets peeled off 5404 * into a new socket. 5405 */ 5406 asoc->secid = sksec->sid; 5407 5408 return selinux_sctp_process_new_assoc(asoc, skb); 5409 } 5410 5411 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5412 * based on their @optname. 5413 */ 5414 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5415 struct sockaddr *address, 5416 int addrlen) 5417 { 5418 int len, err = 0, walk_size = 0; 5419 void *addr_buf; 5420 struct sockaddr *addr; 5421 struct socket *sock; 5422 5423 if (!selinux_policycap_extsockclass()) 5424 return 0; 5425 5426 /* Process one or more addresses that may be IPv4 or IPv6 */ 5427 sock = sk->sk_socket; 5428 addr_buf = address; 5429 5430 while (walk_size < addrlen) { 5431 if (walk_size + sizeof(sa_family_t) > addrlen) 5432 return -EINVAL; 5433 5434 addr = addr_buf; 5435 switch (addr->sa_family) { 5436 case AF_UNSPEC: 5437 case AF_INET: 5438 len = sizeof(struct sockaddr_in); 5439 break; 5440 case AF_INET6: 5441 len = sizeof(struct sockaddr_in6); 5442 break; 5443 default: 5444 return -EINVAL; 5445 } 5446 5447 if (walk_size + len > addrlen) 5448 return -EINVAL; 5449 5450 err = -EINVAL; 5451 switch (optname) { 5452 /* Bind checks */ 5453 case SCTP_PRIMARY_ADDR: 5454 case SCTP_SET_PEER_PRIMARY_ADDR: 5455 case SCTP_SOCKOPT_BINDX_ADD: 5456 err = selinux_socket_bind(sock, addr, len); 5457 break; 5458 /* Connect checks */ 5459 case SCTP_SOCKOPT_CONNECTX: 5460 case SCTP_PARAM_SET_PRIMARY: 5461 case SCTP_PARAM_ADD_IP: 5462 case SCTP_SENDMSG_CONNECT: 5463 err = selinux_socket_connect_helper(sock, addr, len); 5464 if (err) 5465 return err; 5466 5467 /* As selinux_sctp_bind_connect() is called by the 5468 * SCTP protocol layer, the socket is already locked, 5469 * therefore selinux_netlbl_socket_connect_locked() 5470 * is called here. The situations handled are: 5471 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5472 * whenever a new IP address is added or when a new 5473 * primary address is selected. 5474 * Note that an SCTP connect(2) call happens before 5475 * the SCTP protocol layer and is handled via 5476 * selinux_socket_connect(). 5477 */ 5478 err = selinux_netlbl_socket_connect_locked(sk, addr); 5479 break; 5480 } 5481 5482 if (err) 5483 return err; 5484 5485 addr_buf += len; 5486 walk_size += len; 5487 } 5488 5489 return 0; 5490 } 5491 5492 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5493 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5494 struct sock *newsk) 5495 { 5496 struct sk_security_struct *sksec = sk->sk_security; 5497 struct sk_security_struct *newsksec = newsk->sk_security; 5498 5499 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5500 * the non-sctp clone version. 5501 */ 5502 if (!selinux_policycap_extsockclass()) 5503 return selinux_sk_clone_security(sk, newsk); 5504 5505 newsksec->sid = asoc->secid; 5506 newsksec->peer_sid = asoc->peer_secid; 5507 newsksec->sclass = sksec->sclass; 5508 selinux_netlbl_sctp_sk_clone(sk, newsk); 5509 } 5510 5511 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5512 { 5513 struct sk_security_struct *ssksec = ssk->sk_security; 5514 struct sk_security_struct *sksec = sk->sk_security; 5515 5516 ssksec->sclass = sksec->sclass; 5517 ssksec->sid = sksec->sid; 5518 5519 /* replace the existing subflow label deleting the existing one 5520 * and re-recreating a new label using the updated context 5521 */ 5522 selinux_netlbl_sk_security_free(ssksec); 5523 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5524 } 5525 5526 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5527 struct request_sock *req) 5528 { 5529 struct sk_security_struct *sksec = sk->sk_security; 5530 int err; 5531 u16 family = req->rsk_ops->family; 5532 u32 connsid; 5533 u32 peersid; 5534 5535 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5536 if (err) 5537 return err; 5538 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5539 if (err) 5540 return err; 5541 req->secid = connsid; 5542 req->peer_secid = peersid; 5543 5544 return selinux_netlbl_inet_conn_request(req, family); 5545 } 5546 5547 static void selinux_inet_csk_clone(struct sock *newsk, 5548 const struct request_sock *req) 5549 { 5550 struct sk_security_struct *newsksec = newsk->sk_security; 5551 5552 newsksec->sid = req->secid; 5553 newsksec->peer_sid = req->peer_secid; 5554 /* NOTE: Ideally, we should also get the isec->sid for the 5555 new socket in sync, but we don't have the isec available yet. 5556 So we will wait until sock_graft to do it, by which 5557 time it will have been created and available. */ 5558 5559 /* We don't need to take any sort of lock here as we are the only 5560 * thread with access to newsksec */ 5561 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5562 } 5563 5564 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5565 { 5566 u16 family = sk->sk_family; 5567 struct sk_security_struct *sksec = sk->sk_security; 5568 5569 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5570 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5571 family = PF_INET; 5572 5573 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5574 } 5575 5576 static int selinux_secmark_relabel_packet(u32 sid) 5577 { 5578 return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO, 5579 NULL); 5580 } 5581 5582 static void selinux_secmark_refcount_inc(void) 5583 { 5584 atomic_inc(&selinux_secmark_refcount); 5585 } 5586 5587 static void selinux_secmark_refcount_dec(void) 5588 { 5589 atomic_dec(&selinux_secmark_refcount); 5590 } 5591 5592 static void selinux_req_classify_flow(const struct request_sock *req, 5593 struct flowi_common *flic) 5594 { 5595 flic->flowic_secid = req->secid; 5596 } 5597 5598 static int selinux_tun_dev_alloc_security(void **security) 5599 { 5600 struct tun_security_struct *tunsec; 5601 5602 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5603 if (!tunsec) 5604 return -ENOMEM; 5605 tunsec->sid = current_sid(); 5606 5607 *security = tunsec; 5608 return 0; 5609 } 5610 5611 static void selinux_tun_dev_free_security(void *security) 5612 { 5613 kfree(security); 5614 } 5615 5616 static int selinux_tun_dev_create(void) 5617 { 5618 u32 sid = current_sid(); 5619 5620 /* we aren't taking into account the "sockcreate" SID since the socket 5621 * that is being created here is not a socket in the traditional sense, 5622 * instead it is a private sock, accessible only to the kernel, and 5623 * representing a wide range of network traffic spanning multiple 5624 * connections unlike traditional sockets - check the TUN driver to 5625 * get a better understanding of why this socket is special */ 5626 5627 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5628 NULL); 5629 } 5630 5631 static int selinux_tun_dev_attach_queue(void *security) 5632 { 5633 struct tun_security_struct *tunsec = security; 5634 5635 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5636 TUN_SOCKET__ATTACH_QUEUE, NULL); 5637 } 5638 5639 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5640 { 5641 struct tun_security_struct *tunsec = security; 5642 struct sk_security_struct *sksec = sk->sk_security; 5643 5644 /* we don't currently perform any NetLabel based labeling here and it 5645 * isn't clear that we would want to do so anyway; while we could apply 5646 * labeling without the support of the TUN user the resulting labeled 5647 * traffic from the other end of the connection would almost certainly 5648 * cause confusion to the TUN user that had no idea network labeling 5649 * protocols were being used */ 5650 5651 sksec->sid = tunsec->sid; 5652 sksec->sclass = SECCLASS_TUN_SOCKET; 5653 5654 return 0; 5655 } 5656 5657 static int selinux_tun_dev_open(void *security) 5658 { 5659 struct tun_security_struct *tunsec = security; 5660 u32 sid = current_sid(); 5661 int err; 5662 5663 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5664 TUN_SOCKET__RELABELFROM, NULL); 5665 if (err) 5666 return err; 5667 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5668 TUN_SOCKET__RELABELTO, NULL); 5669 if (err) 5670 return err; 5671 tunsec->sid = sid; 5672 5673 return 0; 5674 } 5675 5676 #ifdef CONFIG_NETFILTER 5677 5678 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5679 const struct nf_hook_state *state) 5680 { 5681 int ifindex; 5682 u16 family; 5683 char *addrp; 5684 u32 peer_sid; 5685 struct common_audit_data ad; 5686 struct lsm_network_audit net; 5687 int secmark_active, peerlbl_active; 5688 5689 if (!selinux_policycap_netpeer()) 5690 return NF_ACCEPT; 5691 5692 secmark_active = selinux_secmark_enabled(); 5693 peerlbl_active = selinux_peerlbl_enabled(); 5694 if (!secmark_active && !peerlbl_active) 5695 return NF_ACCEPT; 5696 5697 family = state->pf; 5698 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5699 return NF_DROP; 5700 5701 ifindex = state->in->ifindex; 5702 ad_net_init_from_iif(&ad, &net, ifindex, family); 5703 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5704 return NF_DROP; 5705 5706 if (peerlbl_active) { 5707 int err; 5708 5709 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5710 addrp, family, peer_sid, &ad); 5711 if (err) { 5712 selinux_netlbl_err(skb, family, err, 1); 5713 return NF_DROP; 5714 } 5715 } 5716 5717 if (secmark_active) 5718 if (avc_has_perm(peer_sid, skb->secmark, 5719 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5720 return NF_DROP; 5721 5722 if (netlbl_enabled()) 5723 /* we do this in the FORWARD path and not the POST_ROUTING 5724 * path because we want to make sure we apply the necessary 5725 * labeling before IPsec is applied so we can leverage AH 5726 * protection */ 5727 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5728 return NF_DROP; 5729 5730 return NF_ACCEPT; 5731 } 5732 5733 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5734 const struct nf_hook_state *state) 5735 { 5736 struct sock *sk; 5737 u32 sid; 5738 5739 if (!netlbl_enabled()) 5740 return NF_ACCEPT; 5741 5742 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5743 * because we want to make sure we apply the necessary labeling 5744 * before IPsec is applied so we can leverage AH protection */ 5745 sk = skb->sk; 5746 if (sk) { 5747 struct sk_security_struct *sksec; 5748 5749 if (sk_listener(sk)) 5750 /* if the socket is the listening state then this 5751 * packet is a SYN-ACK packet which means it needs to 5752 * be labeled based on the connection/request_sock and 5753 * not the parent socket. unfortunately, we can't 5754 * lookup the request_sock yet as it isn't queued on 5755 * the parent socket until after the SYN-ACK is sent. 5756 * the "solution" is to simply pass the packet as-is 5757 * as any IP option based labeling should be copied 5758 * from the initial connection request (in the IP 5759 * layer). it is far from ideal, but until we get a 5760 * security label in the packet itself this is the 5761 * best we can do. */ 5762 return NF_ACCEPT; 5763 5764 /* standard practice, label using the parent socket */ 5765 sksec = sk->sk_security; 5766 sid = sksec->sid; 5767 } else 5768 sid = SECINITSID_KERNEL; 5769 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5770 return NF_DROP; 5771 5772 return NF_ACCEPT; 5773 } 5774 5775 5776 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5777 const struct nf_hook_state *state) 5778 { 5779 struct sock *sk; 5780 struct sk_security_struct *sksec; 5781 struct common_audit_data ad; 5782 struct lsm_network_audit net; 5783 u8 proto = 0; 5784 5785 sk = skb_to_full_sk(skb); 5786 if (sk == NULL) 5787 return NF_ACCEPT; 5788 sksec = sk->sk_security; 5789 5790 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5791 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5792 return NF_DROP; 5793 5794 if (selinux_secmark_enabled()) 5795 if (avc_has_perm(sksec->sid, skb->secmark, 5796 SECCLASS_PACKET, PACKET__SEND, &ad)) 5797 return NF_DROP_ERR(-ECONNREFUSED); 5798 5799 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5800 return NF_DROP_ERR(-ECONNREFUSED); 5801 5802 return NF_ACCEPT; 5803 } 5804 5805 static unsigned int selinux_ip_postroute(void *priv, 5806 struct sk_buff *skb, 5807 const struct nf_hook_state *state) 5808 { 5809 u16 family; 5810 u32 secmark_perm; 5811 u32 peer_sid; 5812 int ifindex; 5813 struct sock *sk; 5814 struct common_audit_data ad; 5815 struct lsm_network_audit net; 5816 char *addrp; 5817 int secmark_active, peerlbl_active; 5818 5819 /* If any sort of compatibility mode is enabled then handoff processing 5820 * to the selinux_ip_postroute_compat() function to deal with the 5821 * special handling. We do this in an attempt to keep this function 5822 * as fast and as clean as possible. */ 5823 if (!selinux_policycap_netpeer()) 5824 return selinux_ip_postroute_compat(skb, state); 5825 5826 secmark_active = selinux_secmark_enabled(); 5827 peerlbl_active = selinux_peerlbl_enabled(); 5828 if (!secmark_active && !peerlbl_active) 5829 return NF_ACCEPT; 5830 5831 sk = skb_to_full_sk(skb); 5832 5833 #ifdef CONFIG_XFRM 5834 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5835 * packet transformation so allow the packet to pass without any checks 5836 * since we'll have another chance to perform access control checks 5837 * when the packet is on it's final way out. 5838 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5839 * is NULL, in this case go ahead and apply access control. 5840 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5841 * TCP listening state we cannot wait until the XFRM processing 5842 * is done as we will miss out on the SA label if we do; 5843 * unfortunately, this means more work, but it is only once per 5844 * connection. */ 5845 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5846 !(sk && sk_listener(sk))) 5847 return NF_ACCEPT; 5848 #endif 5849 5850 family = state->pf; 5851 if (sk == NULL) { 5852 /* Without an associated socket the packet is either coming 5853 * from the kernel or it is being forwarded; check the packet 5854 * to determine which and if the packet is being forwarded 5855 * query the packet directly to determine the security label. */ 5856 if (skb->skb_iif) { 5857 secmark_perm = PACKET__FORWARD_OUT; 5858 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5859 return NF_DROP; 5860 } else { 5861 secmark_perm = PACKET__SEND; 5862 peer_sid = SECINITSID_KERNEL; 5863 } 5864 } else if (sk_listener(sk)) { 5865 /* Locally generated packet but the associated socket is in the 5866 * listening state which means this is a SYN-ACK packet. In 5867 * this particular case the correct security label is assigned 5868 * to the connection/request_sock but unfortunately we can't 5869 * query the request_sock as it isn't queued on the parent 5870 * socket until after the SYN-ACK packet is sent; the only 5871 * viable choice is to regenerate the label like we do in 5872 * selinux_inet_conn_request(). See also selinux_ip_output() 5873 * for similar problems. */ 5874 u32 skb_sid; 5875 struct sk_security_struct *sksec; 5876 5877 sksec = sk->sk_security; 5878 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5879 return NF_DROP; 5880 /* At this point, if the returned skb peerlbl is SECSID_NULL 5881 * and the packet has been through at least one XFRM 5882 * transformation then we must be dealing with the "final" 5883 * form of labeled IPsec packet; since we've already applied 5884 * all of our access controls on this packet we can safely 5885 * pass the packet. */ 5886 if (skb_sid == SECSID_NULL) { 5887 switch (family) { 5888 case PF_INET: 5889 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5890 return NF_ACCEPT; 5891 break; 5892 case PF_INET6: 5893 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5894 return NF_ACCEPT; 5895 break; 5896 default: 5897 return NF_DROP_ERR(-ECONNREFUSED); 5898 } 5899 } 5900 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5901 return NF_DROP; 5902 secmark_perm = PACKET__SEND; 5903 } else { 5904 /* Locally generated packet, fetch the security label from the 5905 * associated socket. */ 5906 struct sk_security_struct *sksec = sk->sk_security; 5907 peer_sid = sksec->sid; 5908 secmark_perm = PACKET__SEND; 5909 } 5910 5911 ifindex = state->out->ifindex; 5912 ad_net_init_from_iif(&ad, &net, ifindex, family); 5913 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5914 return NF_DROP; 5915 5916 if (secmark_active) 5917 if (avc_has_perm(peer_sid, skb->secmark, 5918 SECCLASS_PACKET, secmark_perm, &ad)) 5919 return NF_DROP_ERR(-ECONNREFUSED); 5920 5921 if (peerlbl_active) { 5922 u32 if_sid; 5923 u32 node_sid; 5924 5925 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5926 return NF_DROP; 5927 if (avc_has_perm(peer_sid, if_sid, 5928 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5929 return NF_DROP_ERR(-ECONNREFUSED); 5930 5931 if (sel_netnode_sid(addrp, family, &node_sid)) 5932 return NF_DROP; 5933 if (avc_has_perm(peer_sid, node_sid, 5934 SECCLASS_NODE, NODE__SENDTO, &ad)) 5935 return NF_DROP_ERR(-ECONNREFUSED); 5936 } 5937 5938 return NF_ACCEPT; 5939 } 5940 #endif /* CONFIG_NETFILTER */ 5941 5942 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5943 { 5944 int rc = 0; 5945 unsigned int msg_len; 5946 unsigned int data_len = skb->len; 5947 unsigned char *data = skb->data; 5948 struct nlmsghdr *nlh; 5949 struct sk_security_struct *sksec = sk->sk_security; 5950 u16 sclass = sksec->sclass; 5951 u32 perm; 5952 5953 while (data_len >= nlmsg_total_size(0)) { 5954 nlh = (struct nlmsghdr *)data; 5955 5956 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5957 * users which means we can't reject skb's with bogus 5958 * length fields; our solution is to follow what 5959 * netlink_rcv_skb() does and simply skip processing at 5960 * messages with length fields that are clearly junk 5961 */ 5962 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5963 return 0; 5964 5965 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5966 if (rc == 0) { 5967 rc = sock_has_perm(sk, perm); 5968 if (rc) 5969 return rc; 5970 } else if (rc == -EINVAL) { 5971 /* -EINVAL is a missing msg/perm mapping */ 5972 pr_warn_ratelimited("SELinux: unrecognized netlink" 5973 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5974 " pid=%d comm=%s\n", 5975 sk->sk_protocol, nlh->nlmsg_type, 5976 secclass_map[sclass - 1].name, 5977 task_pid_nr(current), current->comm); 5978 if (enforcing_enabled() && 5979 !security_get_allow_unknown()) 5980 return rc; 5981 rc = 0; 5982 } else if (rc == -ENOENT) { 5983 /* -ENOENT is a missing socket/class mapping, ignore */ 5984 rc = 0; 5985 } else { 5986 return rc; 5987 } 5988 5989 /* move to the next message after applying netlink padding */ 5990 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5991 if (msg_len >= data_len) 5992 return 0; 5993 data_len -= msg_len; 5994 data += msg_len; 5995 } 5996 5997 return rc; 5998 } 5999 6000 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 6001 { 6002 isec->sclass = sclass; 6003 isec->sid = current_sid(); 6004 } 6005 6006 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 6007 u32 perms) 6008 { 6009 struct ipc_security_struct *isec; 6010 struct common_audit_data ad; 6011 u32 sid = current_sid(); 6012 6013 isec = selinux_ipc(ipc_perms); 6014 6015 ad.type = LSM_AUDIT_DATA_IPC; 6016 ad.u.ipc_id = ipc_perms->key; 6017 6018 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 6019 } 6020 6021 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 6022 { 6023 struct msg_security_struct *msec; 6024 6025 msec = selinux_msg_msg(msg); 6026 msec->sid = SECINITSID_UNLABELED; 6027 6028 return 0; 6029 } 6030 6031 /* message queue security operations */ 6032 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 6033 { 6034 struct ipc_security_struct *isec; 6035 struct common_audit_data ad; 6036 u32 sid = current_sid(); 6037 6038 isec = selinux_ipc(msq); 6039 ipc_init_security(isec, SECCLASS_MSGQ); 6040 6041 ad.type = LSM_AUDIT_DATA_IPC; 6042 ad.u.ipc_id = msq->key; 6043 6044 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6045 MSGQ__CREATE, &ad); 6046 } 6047 6048 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 6049 { 6050 struct ipc_security_struct *isec; 6051 struct common_audit_data ad; 6052 u32 sid = current_sid(); 6053 6054 isec = selinux_ipc(msq); 6055 6056 ad.type = LSM_AUDIT_DATA_IPC; 6057 ad.u.ipc_id = msq->key; 6058 6059 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6060 MSGQ__ASSOCIATE, &ad); 6061 } 6062 6063 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 6064 { 6065 u32 perms; 6066 6067 switch (cmd) { 6068 case IPC_INFO: 6069 case MSG_INFO: 6070 /* No specific object, just general system-wide information. */ 6071 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6072 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6073 case IPC_STAT: 6074 case MSG_STAT: 6075 case MSG_STAT_ANY: 6076 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6077 break; 6078 case IPC_SET: 6079 perms = MSGQ__SETATTR; 6080 break; 6081 case IPC_RMID: 6082 perms = MSGQ__DESTROY; 6083 break; 6084 default: 6085 return 0; 6086 } 6087 6088 return ipc_has_perm(msq, perms); 6089 } 6090 6091 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6092 { 6093 struct ipc_security_struct *isec; 6094 struct msg_security_struct *msec; 6095 struct common_audit_data ad; 6096 u32 sid = current_sid(); 6097 int rc; 6098 6099 isec = selinux_ipc(msq); 6100 msec = selinux_msg_msg(msg); 6101 6102 /* 6103 * First time through, need to assign label to the message 6104 */ 6105 if (msec->sid == SECINITSID_UNLABELED) { 6106 /* 6107 * Compute new sid based on current process and 6108 * message queue this message will be stored in 6109 */ 6110 rc = security_transition_sid(sid, isec->sid, 6111 SECCLASS_MSG, NULL, &msec->sid); 6112 if (rc) 6113 return rc; 6114 } 6115 6116 ad.type = LSM_AUDIT_DATA_IPC; 6117 ad.u.ipc_id = msq->key; 6118 6119 /* Can this process write to the queue? */ 6120 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6121 MSGQ__WRITE, &ad); 6122 if (!rc) 6123 /* Can this process send the message */ 6124 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6125 MSG__SEND, &ad); 6126 if (!rc) 6127 /* Can the message be put in the queue? */ 6128 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6129 MSGQ__ENQUEUE, &ad); 6130 6131 return rc; 6132 } 6133 6134 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6135 struct task_struct *target, 6136 long type, int mode) 6137 { 6138 struct ipc_security_struct *isec; 6139 struct msg_security_struct *msec; 6140 struct common_audit_data ad; 6141 u32 sid = task_sid_obj(target); 6142 int rc; 6143 6144 isec = selinux_ipc(msq); 6145 msec = selinux_msg_msg(msg); 6146 6147 ad.type = LSM_AUDIT_DATA_IPC; 6148 ad.u.ipc_id = msq->key; 6149 6150 rc = avc_has_perm(sid, isec->sid, 6151 SECCLASS_MSGQ, MSGQ__READ, &ad); 6152 if (!rc) 6153 rc = avc_has_perm(sid, msec->sid, 6154 SECCLASS_MSG, MSG__RECEIVE, &ad); 6155 return rc; 6156 } 6157 6158 /* Shared Memory security operations */ 6159 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6160 { 6161 struct ipc_security_struct *isec; 6162 struct common_audit_data ad; 6163 u32 sid = current_sid(); 6164 6165 isec = selinux_ipc(shp); 6166 ipc_init_security(isec, SECCLASS_SHM); 6167 6168 ad.type = LSM_AUDIT_DATA_IPC; 6169 ad.u.ipc_id = shp->key; 6170 6171 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6172 SHM__CREATE, &ad); 6173 } 6174 6175 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6176 { 6177 struct ipc_security_struct *isec; 6178 struct common_audit_data ad; 6179 u32 sid = current_sid(); 6180 6181 isec = selinux_ipc(shp); 6182 6183 ad.type = LSM_AUDIT_DATA_IPC; 6184 ad.u.ipc_id = shp->key; 6185 6186 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6187 SHM__ASSOCIATE, &ad); 6188 } 6189 6190 /* Note, at this point, shp is locked down */ 6191 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6192 { 6193 u32 perms; 6194 6195 switch (cmd) { 6196 case IPC_INFO: 6197 case SHM_INFO: 6198 /* No specific object, just general system-wide information. */ 6199 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6200 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6201 case IPC_STAT: 6202 case SHM_STAT: 6203 case SHM_STAT_ANY: 6204 perms = SHM__GETATTR | SHM__ASSOCIATE; 6205 break; 6206 case IPC_SET: 6207 perms = SHM__SETATTR; 6208 break; 6209 case SHM_LOCK: 6210 case SHM_UNLOCK: 6211 perms = SHM__LOCK; 6212 break; 6213 case IPC_RMID: 6214 perms = SHM__DESTROY; 6215 break; 6216 default: 6217 return 0; 6218 } 6219 6220 return ipc_has_perm(shp, perms); 6221 } 6222 6223 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6224 char __user *shmaddr, int shmflg) 6225 { 6226 u32 perms; 6227 6228 if (shmflg & SHM_RDONLY) 6229 perms = SHM__READ; 6230 else 6231 perms = SHM__READ | SHM__WRITE; 6232 6233 return ipc_has_perm(shp, perms); 6234 } 6235 6236 /* Semaphore security operations */ 6237 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6238 { 6239 struct ipc_security_struct *isec; 6240 struct common_audit_data ad; 6241 u32 sid = current_sid(); 6242 6243 isec = selinux_ipc(sma); 6244 ipc_init_security(isec, SECCLASS_SEM); 6245 6246 ad.type = LSM_AUDIT_DATA_IPC; 6247 ad.u.ipc_id = sma->key; 6248 6249 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6250 SEM__CREATE, &ad); 6251 } 6252 6253 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6254 { 6255 struct ipc_security_struct *isec; 6256 struct common_audit_data ad; 6257 u32 sid = current_sid(); 6258 6259 isec = selinux_ipc(sma); 6260 6261 ad.type = LSM_AUDIT_DATA_IPC; 6262 ad.u.ipc_id = sma->key; 6263 6264 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6265 SEM__ASSOCIATE, &ad); 6266 } 6267 6268 /* Note, at this point, sma is locked down */ 6269 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6270 { 6271 int err; 6272 u32 perms; 6273 6274 switch (cmd) { 6275 case IPC_INFO: 6276 case SEM_INFO: 6277 /* No specific object, just general system-wide information. */ 6278 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6279 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6280 case GETPID: 6281 case GETNCNT: 6282 case GETZCNT: 6283 perms = SEM__GETATTR; 6284 break; 6285 case GETVAL: 6286 case GETALL: 6287 perms = SEM__READ; 6288 break; 6289 case SETVAL: 6290 case SETALL: 6291 perms = SEM__WRITE; 6292 break; 6293 case IPC_RMID: 6294 perms = SEM__DESTROY; 6295 break; 6296 case IPC_SET: 6297 perms = SEM__SETATTR; 6298 break; 6299 case IPC_STAT: 6300 case SEM_STAT: 6301 case SEM_STAT_ANY: 6302 perms = SEM__GETATTR | SEM__ASSOCIATE; 6303 break; 6304 default: 6305 return 0; 6306 } 6307 6308 err = ipc_has_perm(sma, perms); 6309 return err; 6310 } 6311 6312 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6313 struct sembuf *sops, unsigned nsops, int alter) 6314 { 6315 u32 perms; 6316 6317 if (alter) 6318 perms = SEM__READ | SEM__WRITE; 6319 else 6320 perms = SEM__READ; 6321 6322 return ipc_has_perm(sma, perms); 6323 } 6324 6325 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6326 { 6327 u32 av = 0; 6328 6329 av = 0; 6330 if (flag & S_IRUGO) 6331 av |= IPC__UNIX_READ; 6332 if (flag & S_IWUGO) 6333 av |= IPC__UNIX_WRITE; 6334 6335 if (av == 0) 6336 return 0; 6337 6338 return ipc_has_perm(ipcp, av); 6339 } 6340 6341 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6342 { 6343 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6344 *secid = isec->sid; 6345 } 6346 6347 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6348 { 6349 if (inode) 6350 inode_doinit_with_dentry(inode, dentry); 6351 } 6352 6353 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p, 6354 char **value) 6355 { 6356 const struct task_security_struct *tsec; 6357 int error; 6358 u32 sid; 6359 u32 len; 6360 6361 rcu_read_lock(); 6362 tsec = selinux_cred(__task_cred(p)); 6363 if (p != current) { 6364 error = avc_has_perm(current_sid(), tsec->sid, 6365 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6366 if (error) 6367 goto err_unlock; 6368 } 6369 switch (attr) { 6370 case LSM_ATTR_CURRENT: 6371 sid = tsec->sid; 6372 break; 6373 case LSM_ATTR_PREV: 6374 sid = tsec->osid; 6375 break; 6376 case LSM_ATTR_EXEC: 6377 sid = tsec->exec_sid; 6378 break; 6379 case LSM_ATTR_FSCREATE: 6380 sid = tsec->create_sid; 6381 break; 6382 case LSM_ATTR_KEYCREATE: 6383 sid = tsec->keycreate_sid; 6384 break; 6385 case LSM_ATTR_SOCKCREATE: 6386 sid = tsec->sockcreate_sid; 6387 break; 6388 default: 6389 error = -EOPNOTSUPP; 6390 goto err_unlock; 6391 } 6392 rcu_read_unlock(); 6393 6394 if (sid == SECSID_NULL) { 6395 *value = NULL; 6396 return 0; 6397 } 6398 6399 error = security_sid_to_context(sid, value, &len); 6400 if (error) 6401 return error; 6402 return len; 6403 6404 err_unlock: 6405 rcu_read_unlock(); 6406 return error; 6407 } 6408 6409 static int selinux_lsm_setattr(u64 attr, void *value, size_t size) 6410 { 6411 struct task_security_struct *tsec; 6412 struct cred *new; 6413 u32 mysid = current_sid(), sid = 0, ptsid; 6414 int error; 6415 char *str = value; 6416 6417 /* 6418 * Basic control over ability to set these attributes at all. 6419 */ 6420 switch (attr) { 6421 case LSM_ATTR_EXEC: 6422 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6423 PROCESS__SETEXEC, NULL); 6424 break; 6425 case LSM_ATTR_FSCREATE: 6426 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6427 PROCESS__SETFSCREATE, NULL); 6428 break; 6429 case LSM_ATTR_KEYCREATE: 6430 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6431 PROCESS__SETKEYCREATE, NULL); 6432 break; 6433 case LSM_ATTR_SOCKCREATE: 6434 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6435 PROCESS__SETSOCKCREATE, NULL); 6436 break; 6437 case LSM_ATTR_CURRENT: 6438 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6439 PROCESS__SETCURRENT, NULL); 6440 break; 6441 default: 6442 error = -EOPNOTSUPP; 6443 break; 6444 } 6445 if (error) 6446 return error; 6447 6448 /* Obtain a SID for the context, if one was specified. */ 6449 if (size && str[0] && str[0] != '\n') { 6450 if (str[size-1] == '\n') { 6451 str[size-1] = 0; 6452 size--; 6453 } 6454 error = security_context_to_sid(value, size, 6455 &sid, GFP_KERNEL); 6456 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) { 6457 if (!has_cap_mac_admin(true)) { 6458 struct audit_buffer *ab; 6459 size_t audit_size; 6460 6461 /* We strip a nul only if it is at the end, 6462 * otherwise the context contains a nul and 6463 * we should audit that */ 6464 if (str[size - 1] == '\0') 6465 audit_size = size - 1; 6466 else 6467 audit_size = size; 6468 ab = audit_log_start(audit_context(), 6469 GFP_ATOMIC, 6470 AUDIT_SELINUX_ERR); 6471 if (!ab) 6472 return error; 6473 audit_log_format(ab, "op=fscreate invalid_context="); 6474 audit_log_n_untrustedstring(ab, value, 6475 audit_size); 6476 audit_log_end(ab); 6477 6478 return error; 6479 } 6480 error = security_context_to_sid_force(value, size, 6481 &sid); 6482 } 6483 if (error) 6484 return error; 6485 } 6486 6487 new = prepare_creds(); 6488 if (!new) 6489 return -ENOMEM; 6490 6491 /* Permission checking based on the specified context is 6492 performed during the actual operation (execve, 6493 open/mkdir/...), when we know the full context of the 6494 operation. See selinux_bprm_creds_for_exec for the execve 6495 checks and may_create for the file creation checks. The 6496 operation will then fail if the context is not permitted. */ 6497 tsec = selinux_cred(new); 6498 if (attr == LSM_ATTR_EXEC) { 6499 tsec->exec_sid = sid; 6500 } else if (attr == LSM_ATTR_FSCREATE) { 6501 tsec->create_sid = sid; 6502 } else if (attr == LSM_ATTR_KEYCREATE) { 6503 if (sid) { 6504 error = avc_has_perm(mysid, sid, 6505 SECCLASS_KEY, KEY__CREATE, NULL); 6506 if (error) 6507 goto abort_change; 6508 } 6509 tsec->keycreate_sid = sid; 6510 } else if (attr == LSM_ATTR_SOCKCREATE) { 6511 tsec->sockcreate_sid = sid; 6512 } else if (attr == LSM_ATTR_CURRENT) { 6513 error = -EINVAL; 6514 if (sid == 0) 6515 goto abort_change; 6516 6517 if (!current_is_single_threaded()) { 6518 error = security_bounded_transition(tsec->sid, sid); 6519 if (error) 6520 goto abort_change; 6521 } 6522 6523 /* Check permissions for the transition. */ 6524 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6525 PROCESS__DYNTRANSITION, NULL); 6526 if (error) 6527 goto abort_change; 6528 6529 /* Check for ptracing, and update the task SID if ok. 6530 Otherwise, leave SID unchanged and fail. */ 6531 ptsid = ptrace_parent_sid(); 6532 if (ptsid != 0) { 6533 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6534 PROCESS__PTRACE, NULL); 6535 if (error) 6536 goto abort_change; 6537 } 6538 6539 tsec->sid = sid; 6540 } else { 6541 error = -EINVAL; 6542 goto abort_change; 6543 } 6544 6545 commit_creds(new); 6546 return size; 6547 6548 abort_change: 6549 abort_creds(new); 6550 return error; 6551 } 6552 6553 /** 6554 * selinux_getselfattr - Get SELinux current task attributes 6555 * @attr: the requested attribute 6556 * @ctx: buffer to receive the result 6557 * @size: buffer size (input), buffer size used (output) 6558 * @flags: unused 6559 * 6560 * Fill the passed user space @ctx with the details of the requested 6561 * attribute. 6562 * 6563 * Returns the number of attributes on success, an error code otherwise. 6564 * There will only ever be one attribute. 6565 */ 6566 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, 6567 u32 *size, u32 flags) 6568 { 6569 int rc; 6570 char *val = NULL; 6571 int val_len; 6572 6573 val_len = selinux_lsm_getattr(attr, current, &val); 6574 if (val_len < 0) 6575 return val_len; 6576 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0); 6577 kfree(val); 6578 return (!rc ? 1 : rc); 6579 } 6580 6581 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx, 6582 u32 size, u32 flags) 6583 { 6584 int rc; 6585 6586 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len); 6587 if (rc > 0) 6588 return 0; 6589 return rc; 6590 } 6591 6592 static int selinux_getprocattr(struct task_struct *p, 6593 const char *name, char **value) 6594 { 6595 unsigned int attr = lsm_name_to_attr(name); 6596 int rc; 6597 6598 if (attr) { 6599 rc = selinux_lsm_getattr(attr, p, value); 6600 if (rc != -EOPNOTSUPP) 6601 return rc; 6602 } 6603 6604 return -EINVAL; 6605 } 6606 6607 static int selinux_setprocattr(const char *name, void *value, size_t size) 6608 { 6609 int attr = lsm_name_to_attr(name); 6610 6611 if (attr) 6612 return selinux_lsm_setattr(attr, value, size); 6613 return -EINVAL; 6614 } 6615 6616 static int selinux_ismaclabel(const char *name) 6617 { 6618 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6619 } 6620 6621 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6622 { 6623 return security_sid_to_context(secid, 6624 secdata, seclen); 6625 } 6626 6627 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6628 { 6629 return security_context_to_sid(secdata, seclen, 6630 secid, GFP_KERNEL); 6631 } 6632 6633 static void selinux_release_secctx(char *secdata, u32 seclen) 6634 { 6635 kfree(secdata); 6636 } 6637 6638 static void selinux_inode_invalidate_secctx(struct inode *inode) 6639 { 6640 struct inode_security_struct *isec = selinux_inode(inode); 6641 6642 spin_lock(&isec->lock); 6643 isec->initialized = LABEL_INVALID; 6644 spin_unlock(&isec->lock); 6645 } 6646 6647 /* 6648 * called with inode->i_mutex locked 6649 */ 6650 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6651 { 6652 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6653 ctx, ctxlen, 0); 6654 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6655 return rc == -EOPNOTSUPP ? 0 : rc; 6656 } 6657 6658 /* 6659 * called with inode->i_mutex locked 6660 */ 6661 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6662 { 6663 return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6664 ctx, ctxlen, 0, NULL); 6665 } 6666 6667 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6668 { 6669 int len = 0; 6670 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6671 XATTR_SELINUX_SUFFIX, ctx, true); 6672 if (len < 0) 6673 return len; 6674 *ctxlen = len; 6675 return 0; 6676 } 6677 #ifdef CONFIG_KEYS 6678 6679 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6680 unsigned long flags) 6681 { 6682 const struct task_security_struct *tsec; 6683 struct key_security_struct *ksec; 6684 6685 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6686 if (!ksec) 6687 return -ENOMEM; 6688 6689 tsec = selinux_cred(cred); 6690 if (tsec->keycreate_sid) 6691 ksec->sid = tsec->keycreate_sid; 6692 else 6693 ksec->sid = tsec->sid; 6694 6695 k->security = ksec; 6696 return 0; 6697 } 6698 6699 static void selinux_key_free(struct key *k) 6700 { 6701 struct key_security_struct *ksec = k->security; 6702 6703 k->security = NULL; 6704 kfree(ksec); 6705 } 6706 6707 static int selinux_key_permission(key_ref_t key_ref, 6708 const struct cred *cred, 6709 enum key_need_perm need_perm) 6710 { 6711 struct key *key; 6712 struct key_security_struct *ksec; 6713 u32 perm, sid; 6714 6715 switch (need_perm) { 6716 case KEY_NEED_VIEW: 6717 perm = KEY__VIEW; 6718 break; 6719 case KEY_NEED_READ: 6720 perm = KEY__READ; 6721 break; 6722 case KEY_NEED_WRITE: 6723 perm = KEY__WRITE; 6724 break; 6725 case KEY_NEED_SEARCH: 6726 perm = KEY__SEARCH; 6727 break; 6728 case KEY_NEED_LINK: 6729 perm = KEY__LINK; 6730 break; 6731 case KEY_NEED_SETATTR: 6732 perm = KEY__SETATTR; 6733 break; 6734 case KEY_NEED_UNLINK: 6735 case KEY_SYSADMIN_OVERRIDE: 6736 case KEY_AUTHTOKEN_OVERRIDE: 6737 case KEY_DEFER_PERM_CHECK: 6738 return 0; 6739 default: 6740 WARN_ON(1); 6741 return -EPERM; 6742 6743 } 6744 6745 sid = cred_sid(cred); 6746 key = key_ref_to_ptr(key_ref); 6747 ksec = key->security; 6748 6749 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6750 } 6751 6752 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6753 { 6754 struct key_security_struct *ksec = key->security; 6755 char *context = NULL; 6756 unsigned len; 6757 int rc; 6758 6759 rc = security_sid_to_context(ksec->sid, 6760 &context, &len); 6761 if (!rc) 6762 rc = len; 6763 *_buffer = context; 6764 return rc; 6765 } 6766 6767 #ifdef CONFIG_KEY_NOTIFICATIONS 6768 static int selinux_watch_key(struct key *key) 6769 { 6770 struct key_security_struct *ksec = key->security; 6771 u32 sid = current_sid(); 6772 6773 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6774 } 6775 #endif 6776 #endif 6777 6778 #ifdef CONFIG_SECURITY_INFINIBAND 6779 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6780 { 6781 struct common_audit_data ad; 6782 int err; 6783 u32 sid = 0; 6784 struct ib_security_struct *sec = ib_sec; 6785 struct lsm_ibpkey_audit ibpkey; 6786 6787 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6788 if (err) 6789 return err; 6790 6791 ad.type = LSM_AUDIT_DATA_IBPKEY; 6792 ibpkey.subnet_prefix = subnet_prefix; 6793 ibpkey.pkey = pkey_val; 6794 ad.u.ibpkey = &ibpkey; 6795 return avc_has_perm(sec->sid, sid, 6796 SECCLASS_INFINIBAND_PKEY, 6797 INFINIBAND_PKEY__ACCESS, &ad); 6798 } 6799 6800 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6801 u8 port_num) 6802 { 6803 struct common_audit_data ad; 6804 int err; 6805 u32 sid = 0; 6806 struct ib_security_struct *sec = ib_sec; 6807 struct lsm_ibendport_audit ibendport; 6808 6809 err = security_ib_endport_sid(dev_name, port_num, 6810 &sid); 6811 6812 if (err) 6813 return err; 6814 6815 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6816 ibendport.dev_name = dev_name; 6817 ibendport.port = port_num; 6818 ad.u.ibendport = &ibendport; 6819 return avc_has_perm(sec->sid, sid, 6820 SECCLASS_INFINIBAND_ENDPORT, 6821 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6822 } 6823 6824 static int selinux_ib_alloc_security(void **ib_sec) 6825 { 6826 struct ib_security_struct *sec; 6827 6828 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6829 if (!sec) 6830 return -ENOMEM; 6831 sec->sid = current_sid(); 6832 6833 *ib_sec = sec; 6834 return 0; 6835 } 6836 6837 static void selinux_ib_free_security(void *ib_sec) 6838 { 6839 kfree(ib_sec); 6840 } 6841 #endif 6842 6843 #ifdef CONFIG_BPF_SYSCALL 6844 static int selinux_bpf(int cmd, union bpf_attr *attr, 6845 unsigned int size) 6846 { 6847 u32 sid = current_sid(); 6848 int ret; 6849 6850 switch (cmd) { 6851 case BPF_MAP_CREATE: 6852 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6853 NULL); 6854 break; 6855 case BPF_PROG_LOAD: 6856 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6857 NULL); 6858 break; 6859 default: 6860 ret = 0; 6861 break; 6862 } 6863 6864 return ret; 6865 } 6866 6867 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6868 { 6869 u32 av = 0; 6870 6871 if (fmode & FMODE_READ) 6872 av |= BPF__MAP_READ; 6873 if (fmode & FMODE_WRITE) 6874 av |= BPF__MAP_WRITE; 6875 return av; 6876 } 6877 6878 /* This function will check the file pass through unix socket or binder to see 6879 * if it is a bpf related object. And apply corresponding checks on the bpf 6880 * object based on the type. The bpf maps and programs, not like other files and 6881 * socket, are using a shared anonymous inode inside the kernel as their inode. 6882 * So checking that inode cannot identify if the process have privilege to 6883 * access the bpf object and that's why we have to add this additional check in 6884 * selinux_file_receive and selinux_binder_transfer_files. 6885 */ 6886 static int bpf_fd_pass(const struct file *file, u32 sid) 6887 { 6888 struct bpf_security_struct *bpfsec; 6889 struct bpf_prog *prog; 6890 struct bpf_map *map; 6891 int ret; 6892 6893 if (file->f_op == &bpf_map_fops) { 6894 map = file->private_data; 6895 bpfsec = map->security; 6896 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6897 bpf_map_fmode_to_av(file->f_mode), NULL); 6898 if (ret) 6899 return ret; 6900 } else if (file->f_op == &bpf_prog_fops) { 6901 prog = file->private_data; 6902 bpfsec = prog->aux->security; 6903 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6904 BPF__PROG_RUN, NULL); 6905 if (ret) 6906 return ret; 6907 } 6908 return 0; 6909 } 6910 6911 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6912 { 6913 u32 sid = current_sid(); 6914 struct bpf_security_struct *bpfsec; 6915 6916 bpfsec = map->security; 6917 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6918 bpf_map_fmode_to_av(fmode), NULL); 6919 } 6920 6921 static int selinux_bpf_prog(struct bpf_prog *prog) 6922 { 6923 u32 sid = current_sid(); 6924 struct bpf_security_struct *bpfsec; 6925 6926 bpfsec = prog->aux->security; 6927 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6928 BPF__PROG_RUN, NULL); 6929 } 6930 6931 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 6932 struct bpf_token *token) 6933 { 6934 struct bpf_security_struct *bpfsec; 6935 6936 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6937 if (!bpfsec) 6938 return -ENOMEM; 6939 6940 bpfsec->sid = current_sid(); 6941 map->security = bpfsec; 6942 6943 return 0; 6944 } 6945 6946 static void selinux_bpf_map_free(struct bpf_map *map) 6947 { 6948 struct bpf_security_struct *bpfsec = map->security; 6949 6950 map->security = NULL; 6951 kfree(bpfsec); 6952 } 6953 6954 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 6955 struct bpf_token *token) 6956 { 6957 struct bpf_security_struct *bpfsec; 6958 6959 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6960 if (!bpfsec) 6961 return -ENOMEM; 6962 6963 bpfsec->sid = current_sid(); 6964 prog->aux->security = bpfsec; 6965 6966 return 0; 6967 } 6968 6969 static void selinux_bpf_prog_free(struct bpf_prog *prog) 6970 { 6971 struct bpf_security_struct *bpfsec = prog->aux->security; 6972 6973 prog->aux->security = NULL; 6974 kfree(bpfsec); 6975 } 6976 6977 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 6978 struct path *path) 6979 { 6980 struct bpf_security_struct *bpfsec; 6981 6982 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6983 if (!bpfsec) 6984 return -ENOMEM; 6985 6986 bpfsec->sid = current_sid(); 6987 token->security = bpfsec; 6988 6989 return 0; 6990 } 6991 6992 static void selinux_bpf_token_free(struct bpf_token *token) 6993 { 6994 struct bpf_security_struct *bpfsec = token->security; 6995 6996 token->security = NULL; 6997 kfree(bpfsec); 6998 } 6999 #endif 7000 7001 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 7002 .lbs_cred = sizeof(struct task_security_struct), 7003 .lbs_file = sizeof(struct file_security_struct), 7004 .lbs_inode = sizeof(struct inode_security_struct), 7005 .lbs_ipc = sizeof(struct ipc_security_struct), 7006 .lbs_msg_msg = sizeof(struct msg_security_struct), 7007 .lbs_superblock = sizeof(struct superblock_security_struct), 7008 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 7009 }; 7010 7011 #ifdef CONFIG_PERF_EVENTS 7012 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 7013 { 7014 u32 requested, sid = current_sid(); 7015 7016 if (type == PERF_SECURITY_OPEN) 7017 requested = PERF_EVENT__OPEN; 7018 else if (type == PERF_SECURITY_CPU) 7019 requested = PERF_EVENT__CPU; 7020 else if (type == PERF_SECURITY_KERNEL) 7021 requested = PERF_EVENT__KERNEL; 7022 else if (type == PERF_SECURITY_TRACEPOINT) 7023 requested = PERF_EVENT__TRACEPOINT; 7024 else 7025 return -EINVAL; 7026 7027 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 7028 requested, NULL); 7029 } 7030 7031 static int selinux_perf_event_alloc(struct perf_event *event) 7032 { 7033 struct perf_event_security_struct *perfsec; 7034 7035 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 7036 if (!perfsec) 7037 return -ENOMEM; 7038 7039 perfsec->sid = current_sid(); 7040 event->security = perfsec; 7041 7042 return 0; 7043 } 7044 7045 static void selinux_perf_event_free(struct perf_event *event) 7046 { 7047 struct perf_event_security_struct *perfsec = event->security; 7048 7049 event->security = NULL; 7050 kfree(perfsec); 7051 } 7052 7053 static int selinux_perf_event_read(struct perf_event *event) 7054 { 7055 struct perf_event_security_struct *perfsec = event->security; 7056 u32 sid = current_sid(); 7057 7058 return avc_has_perm(sid, perfsec->sid, 7059 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 7060 } 7061 7062 static int selinux_perf_event_write(struct perf_event *event) 7063 { 7064 struct perf_event_security_struct *perfsec = event->security; 7065 u32 sid = current_sid(); 7066 7067 return avc_has_perm(sid, perfsec->sid, 7068 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 7069 } 7070 #endif 7071 7072 #ifdef CONFIG_IO_URING 7073 /** 7074 * selinux_uring_override_creds - check the requested cred override 7075 * @new: the target creds 7076 * 7077 * Check to see if the current task is allowed to override it's credentials 7078 * to service an io_uring operation. 7079 */ 7080 static int selinux_uring_override_creds(const struct cred *new) 7081 { 7082 return avc_has_perm(current_sid(), cred_sid(new), 7083 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 7084 } 7085 7086 /** 7087 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 7088 * 7089 * Check to see if the current task is allowed to create a new io_uring 7090 * kernel polling thread. 7091 */ 7092 static int selinux_uring_sqpoll(void) 7093 { 7094 u32 sid = current_sid(); 7095 7096 return avc_has_perm(sid, sid, 7097 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 7098 } 7099 7100 /** 7101 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 7102 * @ioucmd: the io_uring command structure 7103 * 7104 * Check to see if the current domain is allowed to execute an 7105 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 7106 * 7107 */ 7108 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 7109 { 7110 struct file *file = ioucmd->file; 7111 struct inode *inode = file_inode(file); 7112 struct inode_security_struct *isec = selinux_inode(inode); 7113 struct common_audit_data ad; 7114 7115 ad.type = LSM_AUDIT_DATA_FILE; 7116 ad.u.file = file; 7117 7118 return avc_has_perm(current_sid(), isec->sid, 7119 SECCLASS_IO_URING, IO_URING__CMD, &ad); 7120 } 7121 #endif /* CONFIG_IO_URING */ 7122 7123 static const struct lsm_id selinux_lsmid = { 7124 .name = "selinux", 7125 .id = LSM_ID_SELINUX, 7126 }; 7127 7128 /* 7129 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 7130 * 1. any hooks that don't belong to (2.) or (3.) below, 7131 * 2. hooks that both access structures allocated by other hooks, and allocate 7132 * structures that can be later accessed by other hooks (mostly "cloning" 7133 * hooks), 7134 * 3. hooks that only allocate structures that can be later accessed by other 7135 * hooks ("allocating" hooks). 7136 * 7137 * Please follow block comment delimiters in the list to keep this order. 7138 */ 7139 static struct security_hook_list selinux_hooks[] __ro_after_init = { 7140 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 7141 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 7142 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 7143 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 7144 7145 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 7146 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 7147 LSM_HOOK_INIT(capget, selinux_capget), 7148 LSM_HOOK_INIT(capset, selinux_capset), 7149 LSM_HOOK_INIT(capable, selinux_capable), 7150 LSM_HOOK_INIT(quotactl, selinux_quotactl), 7151 LSM_HOOK_INIT(quota_on, selinux_quota_on), 7152 LSM_HOOK_INIT(syslog, selinux_syslog), 7153 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 7154 7155 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 7156 7157 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 7158 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 7159 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 7160 7161 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 7162 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 7163 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 7164 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 7165 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 7166 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 7167 LSM_HOOK_INIT(sb_mount, selinux_mount), 7168 LSM_HOOK_INIT(sb_umount, selinux_umount), 7169 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7170 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7171 7172 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7173 7174 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7175 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7176 7177 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7178 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7179 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7180 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7181 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7182 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7183 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7184 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7185 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7186 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7187 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7188 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7189 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7190 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7191 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7192 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7193 LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap), 7194 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7195 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7196 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7197 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7198 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7199 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7200 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7201 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7202 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7203 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7204 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7205 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7206 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7207 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7208 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7209 7210 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7211 7212 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7213 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7214 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7215 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat), 7216 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7217 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7218 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7219 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7220 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7221 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7222 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7223 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7224 7225 LSM_HOOK_INIT(file_open, selinux_file_open), 7226 7227 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7228 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7229 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7230 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7231 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7232 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7233 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7234 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7235 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7236 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7237 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7238 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7239 LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), 7240 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), 7241 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7242 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7243 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7244 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7245 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7246 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7247 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7248 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7249 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7250 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7251 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7252 7253 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7254 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7255 7256 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7257 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7258 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7259 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7260 7261 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7262 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7263 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7264 7265 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7266 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7267 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7268 7269 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7270 7271 LSM_HOOK_INIT(getselfattr, selinux_getselfattr), 7272 LSM_HOOK_INIT(setselfattr, selinux_setselfattr), 7273 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7274 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7275 7276 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7277 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7278 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7279 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7280 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7281 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7282 7283 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7284 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7285 7286 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7287 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7288 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7289 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7290 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7291 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7292 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7293 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7294 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7295 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7296 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7297 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7298 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7299 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7300 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7301 LSM_HOOK_INIT(socket_getpeersec_stream, 7302 selinux_socket_getpeersec_stream), 7303 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7304 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7305 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7306 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7307 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7308 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7309 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7310 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7311 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7312 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7313 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7314 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7315 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7316 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7317 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7318 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7319 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7320 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7321 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7322 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7323 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7324 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7325 #ifdef CONFIG_SECURITY_INFINIBAND 7326 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7327 LSM_HOOK_INIT(ib_endport_manage_subnet, 7328 selinux_ib_endport_manage_subnet), 7329 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7330 #endif 7331 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7332 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7333 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7334 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7335 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7336 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7337 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7338 selinux_xfrm_state_pol_flow_match), 7339 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7340 #endif 7341 7342 #ifdef CONFIG_KEYS 7343 LSM_HOOK_INIT(key_free, selinux_key_free), 7344 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7345 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7346 #ifdef CONFIG_KEY_NOTIFICATIONS 7347 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7348 #endif 7349 #endif 7350 7351 #ifdef CONFIG_AUDIT 7352 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7353 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7354 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7355 #endif 7356 7357 #ifdef CONFIG_BPF_SYSCALL 7358 LSM_HOOK_INIT(bpf, selinux_bpf), 7359 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7360 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7361 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free), 7362 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free), 7363 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free), 7364 #endif 7365 7366 #ifdef CONFIG_PERF_EVENTS 7367 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7368 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7369 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7370 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7371 #endif 7372 7373 #ifdef CONFIG_IO_URING 7374 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7375 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7376 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7377 #endif 7378 7379 /* 7380 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7381 */ 7382 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7383 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7384 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7385 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7386 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7387 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7388 #endif 7389 7390 /* 7391 * PUT "ALLOCATING" HOOKS HERE 7392 */ 7393 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7394 LSM_HOOK_INIT(msg_queue_alloc_security, 7395 selinux_msg_queue_alloc_security), 7396 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7397 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7398 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7399 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7400 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7401 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7402 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7403 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7404 #ifdef CONFIG_SECURITY_INFINIBAND 7405 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7406 #endif 7407 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7408 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7409 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7410 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7411 selinux_xfrm_state_alloc_acquire), 7412 #endif 7413 #ifdef CONFIG_KEYS 7414 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7415 #endif 7416 #ifdef CONFIG_AUDIT 7417 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7418 #endif 7419 #ifdef CONFIG_BPF_SYSCALL 7420 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create), 7421 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load), 7422 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create), 7423 #endif 7424 #ifdef CONFIG_PERF_EVENTS 7425 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7426 #endif 7427 }; 7428 7429 static __init int selinux_init(void) 7430 { 7431 pr_info("SELinux: Initializing.\n"); 7432 7433 memset(&selinux_state, 0, sizeof(selinux_state)); 7434 enforcing_set(selinux_enforcing_boot); 7435 selinux_avc_init(); 7436 mutex_init(&selinux_state.status_lock); 7437 mutex_init(&selinux_state.policy_mutex); 7438 7439 /* Set the security state for the initial task. */ 7440 cred_init_security(); 7441 7442 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7443 if (!default_noexec) 7444 pr_notice("SELinux: virtual memory is executable by default\n"); 7445 7446 avc_init(); 7447 7448 avtab_cache_init(); 7449 7450 ebitmap_cache_init(); 7451 7452 hashtab_cache_init(); 7453 7454 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), 7455 &selinux_lsmid); 7456 7457 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7458 panic("SELinux: Unable to register AVC netcache callback\n"); 7459 7460 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7461 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7462 7463 if (selinux_enforcing_boot) 7464 pr_debug("SELinux: Starting in enforcing mode\n"); 7465 else 7466 pr_debug("SELinux: Starting in permissive mode\n"); 7467 7468 fs_validate_description("selinux", selinux_fs_parameters); 7469 7470 return 0; 7471 } 7472 7473 static void delayed_superblock_init(struct super_block *sb, void *unused) 7474 { 7475 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7476 } 7477 7478 void selinux_complete_init(void) 7479 { 7480 pr_debug("SELinux: Completing initialization.\n"); 7481 7482 /* Set up any superblocks initialized prior to the policy load. */ 7483 pr_debug("SELinux: Setting up existing superblocks.\n"); 7484 iterate_supers(delayed_superblock_init, NULL); 7485 } 7486 7487 /* SELinux requires early initialization in order to label 7488 all processes and objects when they are created. */ 7489 DEFINE_LSM(selinux) = { 7490 .name = "selinux", 7491 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7492 .enabled = &selinux_enabled_boot, 7493 .blobs = &selinux_blob_sizes, 7494 .init = selinux_init, 7495 }; 7496 7497 #if defined(CONFIG_NETFILTER) 7498 static const struct nf_hook_ops selinux_nf_ops[] = { 7499 { 7500 .hook = selinux_ip_postroute, 7501 .pf = NFPROTO_IPV4, 7502 .hooknum = NF_INET_POST_ROUTING, 7503 .priority = NF_IP_PRI_SELINUX_LAST, 7504 }, 7505 { 7506 .hook = selinux_ip_forward, 7507 .pf = NFPROTO_IPV4, 7508 .hooknum = NF_INET_FORWARD, 7509 .priority = NF_IP_PRI_SELINUX_FIRST, 7510 }, 7511 { 7512 .hook = selinux_ip_output, 7513 .pf = NFPROTO_IPV4, 7514 .hooknum = NF_INET_LOCAL_OUT, 7515 .priority = NF_IP_PRI_SELINUX_FIRST, 7516 }, 7517 #if IS_ENABLED(CONFIG_IPV6) 7518 { 7519 .hook = selinux_ip_postroute, 7520 .pf = NFPROTO_IPV6, 7521 .hooknum = NF_INET_POST_ROUTING, 7522 .priority = NF_IP6_PRI_SELINUX_LAST, 7523 }, 7524 { 7525 .hook = selinux_ip_forward, 7526 .pf = NFPROTO_IPV6, 7527 .hooknum = NF_INET_FORWARD, 7528 .priority = NF_IP6_PRI_SELINUX_FIRST, 7529 }, 7530 { 7531 .hook = selinux_ip_output, 7532 .pf = NFPROTO_IPV6, 7533 .hooknum = NF_INET_LOCAL_OUT, 7534 .priority = NF_IP6_PRI_SELINUX_FIRST, 7535 }, 7536 #endif /* IPV6 */ 7537 }; 7538 7539 static int __net_init selinux_nf_register(struct net *net) 7540 { 7541 return nf_register_net_hooks(net, selinux_nf_ops, 7542 ARRAY_SIZE(selinux_nf_ops)); 7543 } 7544 7545 static void __net_exit selinux_nf_unregister(struct net *net) 7546 { 7547 nf_unregister_net_hooks(net, selinux_nf_ops, 7548 ARRAY_SIZE(selinux_nf_ops)); 7549 } 7550 7551 static struct pernet_operations selinux_net_ops = { 7552 .init = selinux_nf_register, 7553 .exit = selinux_nf_unregister, 7554 }; 7555 7556 static int __init selinux_nf_ip_init(void) 7557 { 7558 int err; 7559 7560 if (!selinux_enabled_boot) 7561 return 0; 7562 7563 pr_debug("SELinux: Registering netfilter hooks\n"); 7564 7565 err = register_pernet_subsys(&selinux_net_ops); 7566 if (err) 7567 panic("SELinux: register_pernet_subsys: error %d\n", err); 7568 7569 return 0; 7570 } 7571 __initcall(selinux_nf_ip_init); 7572 #endif /* CONFIG_NETFILTER */ 7573