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 permission for allocating a new virtual mapping. Returns 2206 * 0 if permission is granted, negative error code if not. 2207 * 2208 * Do not audit the selinux permission check, as this is applied to all 2209 * processes that allocate mappings. 2210 */ 2211 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2212 { 2213 return cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2214 CAP_OPT_NOAUDIT, true); 2215 } 2216 2217 /* binprm security operations */ 2218 2219 static u32 ptrace_parent_sid(void) 2220 { 2221 u32 sid = 0; 2222 struct task_struct *tracer; 2223 2224 rcu_read_lock(); 2225 tracer = ptrace_parent(current); 2226 if (tracer) 2227 sid = task_sid_obj(tracer); 2228 rcu_read_unlock(); 2229 2230 return sid; 2231 } 2232 2233 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2234 const struct task_security_struct *old_tsec, 2235 const struct task_security_struct *new_tsec) 2236 { 2237 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2238 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2239 int rc; 2240 u32 av; 2241 2242 if (!nnp && !nosuid) 2243 return 0; /* neither NNP nor nosuid */ 2244 2245 if (new_tsec->sid == old_tsec->sid) 2246 return 0; /* No change in credentials */ 2247 2248 /* 2249 * If the policy enables the nnp_nosuid_transition policy capability, 2250 * then we permit transitions under NNP or nosuid if the 2251 * policy allows the corresponding permission between 2252 * the old and new contexts. 2253 */ 2254 if (selinux_policycap_nnp_nosuid_transition()) { 2255 av = 0; 2256 if (nnp) 2257 av |= PROCESS2__NNP_TRANSITION; 2258 if (nosuid) 2259 av |= PROCESS2__NOSUID_TRANSITION; 2260 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2261 SECCLASS_PROCESS2, av, NULL); 2262 if (!rc) 2263 return 0; 2264 } 2265 2266 /* 2267 * We also permit NNP or nosuid transitions to bounded SIDs, 2268 * i.e. SIDs that are guaranteed to only be allowed a subset 2269 * of the permissions of the current SID. 2270 */ 2271 rc = security_bounded_transition(old_tsec->sid, 2272 new_tsec->sid); 2273 if (!rc) 2274 return 0; 2275 2276 /* 2277 * On failure, preserve the errno values for NNP vs nosuid. 2278 * NNP: Operation not permitted for caller. 2279 * nosuid: Permission denied to file. 2280 */ 2281 if (nnp) 2282 return -EPERM; 2283 return -EACCES; 2284 } 2285 2286 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2287 { 2288 const struct task_security_struct *old_tsec; 2289 struct task_security_struct *new_tsec; 2290 struct inode_security_struct *isec; 2291 struct common_audit_data ad; 2292 struct inode *inode = file_inode(bprm->file); 2293 int rc; 2294 2295 /* SELinux context only depends on initial program or script and not 2296 * the script interpreter */ 2297 2298 old_tsec = selinux_cred(current_cred()); 2299 new_tsec = selinux_cred(bprm->cred); 2300 isec = inode_security(inode); 2301 2302 /* Default to the current task SID. */ 2303 new_tsec->sid = old_tsec->sid; 2304 new_tsec->osid = old_tsec->sid; 2305 2306 /* Reset fs, key, and sock SIDs on execve. */ 2307 new_tsec->create_sid = 0; 2308 new_tsec->keycreate_sid = 0; 2309 new_tsec->sockcreate_sid = 0; 2310 2311 /* 2312 * Before policy is loaded, label any task outside kernel space 2313 * as SECINITSID_INIT, so that any userspace tasks surviving from 2314 * early boot end up with a label different from SECINITSID_KERNEL 2315 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL). 2316 */ 2317 if (!selinux_initialized()) { 2318 new_tsec->sid = SECINITSID_INIT; 2319 /* also clear the exec_sid just in case */ 2320 new_tsec->exec_sid = 0; 2321 return 0; 2322 } 2323 2324 if (old_tsec->exec_sid) { 2325 new_tsec->sid = old_tsec->exec_sid; 2326 /* Reset exec SID on execve. */ 2327 new_tsec->exec_sid = 0; 2328 2329 /* Fail on NNP or nosuid if not an allowed transition. */ 2330 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2331 if (rc) 2332 return rc; 2333 } else { 2334 /* Check for a default transition on this program. */ 2335 rc = security_transition_sid(old_tsec->sid, 2336 isec->sid, SECCLASS_PROCESS, NULL, 2337 &new_tsec->sid); 2338 if (rc) 2339 return rc; 2340 2341 /* 2342 * Fallback to old SID on NNP or nosuid if not an allowed 2343 * transition. 2344 */ 2345 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2346 if (rc) 2347 new_tsec->sid = old_tsec->sid; 2348 } 2349 2350 ad.type = LSM_AUDIT_DATA_FILE; 2351 ad.u.file = bprm->file; 2352 2353 if (new_tsec->sid == old_tsec->sid) { 2354 rc = avc_has_perm(old_tsec->sid, isec->sid, 2355 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2356 if (rc) 2357 return rc; 2358 } else { 2359 /* Check permissions for the transition. */ 2360 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2361 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2362 if (rc) 2363 return rc; 2364 2365 rc = avc_has_perm(new_tsec->sid, isec->sid, 2366 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2367 if (rc) 2368 return rc; 2369 2370 /* Check for shared state */ 2371 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2372 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2373 SECCLASS_PROCESS, PROCESS__SHARE, 2374 NULL); 2375 if (rc) 2376 return -EPERM; 2377 } 2378 2379 /* Make sure that anyone attempting to ptrace over a task that 2380 * changes its SID has the appropriate permit */ 2381 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2382 u32 ptsid = ptrace_parent_sid(); 2383 if (ptsid != 0) { 2384 rc = avc_has_perm(ptsid, new_tsec->sid, 2385 SECCLASS_PROCESS, 2386 PROCESS__PTRACE, NULL); 2387 if (rc) 2388 return -EPERM; 2389 } 2390 } 2391 2392 /* Clear any possibly unsafe personality bits on exec: */ 2393 bprm->per_clear |= PER_CLEAR_ON_SETID; 2394 2395 /* Enable secure mode for SIDs transitions unless 2396 the noatsecure permission is granted between 2397 the two SIDs, i.e. ahp returns 0. */ 2398 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2399 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2400 NULL); 2401 bprm->secureexec |= !!rc; 2402 } 2403 2404 return 0; 2405 } 2406 2407 static int match_file(const void *p, struct file *file, unsigned fd) 2408 { 2409 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2410 } 2411 2412 /* Derived from fs/exec.c:flush_old_files. */ 2413 static inline void flush_unauthorized_files(const struct cred *cred, 2414 struct files_struct *files) 2415 { 2416 struct file *file, *devnull = NULL; 2417 struct tty_struct *tty; 2418 int drop_tty = 0; 2419 unsigned n; 2420 2421 tty = get_current_tty(); 2422 if (tty) { 2423 spin_lock(&tty->files_lock); 2424 if (!list_empty(&tty->tty_files)) { 2425 struct tty_file_private *file_priv; 2426 2427 /* Revalidate access to controlling tty. 2428 Use file_path_has_perm on the tty path directly 2429 rather than using file_has_perm, as this particular 2430 open file may belong to another process and we are 2431 only interested in the inode-based check here. */ 2432 file_priv = list_first_entry(&tty->tty_files, 2433 struct tty_file_private, list); 2434 file = file_priv->file; 2435 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2436 drop_tty = 1; 2437 } 2438 spin_unlock(&tty->files_lock); 2439 tty_kref_put(tty); 2440 } 2441 /* Reset controlling tty. */ 2442 if (drop_tty) 2443 no_tty(); 2444 2445 /* Revalidate access to inherited open files. */ 2446 n = iterate_fd(files, 0, match_file, cred); 2447 if (!n) /* none found? */ 2448 return; 2449 2450 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2451 if (IS_ERR(devnull)) 2452 devnull = NULL; 2453 /* replace all the matching ones with this */ 2454 do { 2455 replace_fd(n - 1, devnull, 0); 2456 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2457 if (devnull) 2458 fput(devnull); 2459 } 2460 2461 /* 2462 * Prepare a process for imminent new credential changes due to exec 2463 */ 2464 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) 2465 { 2466 struct task_security_struct *new_tsec; 2467 struct rlimit *rlim, *initrlim; 2468 int rc, i; 2469 2470 new_tsec = selinux_cred(bprm->cred); 2471 if (new_tsec->sid == new_tsec->osid) 2472 return; 2473 2474 /* Close files for which the new task SID is not authorized. */ 2475 flush_unauthorized_files(bprm->cred, current->files); 2476 2477 /* Always clear parent death signal on SID transitions. */ 2478 current->pdeath_signal = 0; 2479 2480 /* Check whether the new SID can inherit resource limits from the old 2481 * SID. If not, reset all soft limits to the lower of the current 2482 * task's hard limit and the init task's soft limit. 2483 * 2484 * Note that the setting of hard limits (even to lower them) can be 2485 * controlled by the setrlimit check. The inclusion of the init task's 2486 * soft limit into the computation is to avoid resetting soft limits 2487 * higher than the default soft limit for cases where the default is 2488 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2489 */ 2490 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2491 PROCESS__RLIMITINH, NULL); 2492 if (rc) { 2493 /* protect against do_prlimit() */ 2494 task_lock(current); 2495 for (i = 0; i < RLIM_NLIMITS; i++) { 2496 rlim = current->signal->rlim + i; 2497 initrlim = init_task.signal->rlim + i; 2498 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2499 } 2500 task_unlock(current); 2501 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2502 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2503 } 2504 } 2505 2506 /* 2507 * Clean up the process immediately after the installation of new credentials 2508 * due to exec 2509 */ 2510 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) 2511 { 2512 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2513 u32 osid, sid; 2514 int rc; 2515 2516 osid = tsec->osid; 2517 sid = tsec->sid; 2518 2519 if (sid == osid) 2520 return; 2521 2522 /* Check whether the new SID can inherit signal state from the old SID. 2523 * If not, clear itimers to avoid subsequent signal generation and 2524 * flush and unblock signals. 2525 * 2526 * This must occur _after_ the task SID has been updated so that any 2527 * kill done after the flush will be checked against the new SID. 2528 */ 2529 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2530 if (rc) { 2531 clear_itimer(); 2532 2533 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); 2534 if (!fatal_signal_pending(current)) { 2535 flush_sigqueue(¤t->pending); 2536 flush_sigqueue(¤t->signal->shared_pending); 2537 flush_signal_handlers(current, 1); 2538 sigemptyset(¤t->blocked); 2539 recalc_sigpending(); 2540 } 2541 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); 2542 } 2543 2544 /* Wake up the parent if it is waiting so that it can recheck 2545 * wait permission to the new task SID. */ 2546 read_lock(&tasklist_lock); 2547 __wake_up_parent(current, unrcu_pointer(current->real_parent)); 2548 read_unlock(&tasklist_lock); 2549 } 2550 2551 /* superblock security operations */ 2552 2553 static int selinux_sb_alloc_security(struct super_block *sb) 2554 { 2555 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2556 2557 mutex_init(&sbsec->lock); 2558 INIT_LIST_HEAD(&sbsec->isec_head); 2559 spin_lock_init(&sbsec->isec_lock); 2560 sbsec->sid = SECINITSID_UNLABELED; 2561 sbsec->def_sid = SECINITSID_FILE; 2562 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2563 2564 return 0; 2565 } 2566 2567 static inline int opt_len(const char *s) 2568 { 2569 bool open_quote = false; 2570 int len; 2571 char c; 2572 2573 for (len = 0; (c = s[len]) != '\0'; len++) { 2574 if (c == '"') 2575 open_quote = !open_quote; 2576 if (c == ',' && !open_quote) 2577 break; 2578 } 2579 return len; 2580 } 2581 2582 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2583 { 2584 char *from = options; 2585 char *to = options; 2586 bool first = true; 2587 int rc; 2588 2589 while (1) { 2590 int len = opt_len(from); 2591 int token; 2592 char *arg = NULL; 2593 2594 token = match_opt_prefix(from, len, &arg); 2595 2596 if (token != Opt_error) { 2597 char *p, *q; 2598 2599 /* strip quotes */ 2600 if (arg) { 2601 for (p = q = arg; p < from + len; p++) { 2602 char c = *p; 2603 if (c != '"') 2604 *q++ = c; 2605 } 2606 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2607 if (!arg) { 2608 rc = -ENOMEM; 2609 goto free_opt; 2610 } 2611 } 2612 rc = selinux_add_opt(token, arg, mnt_opts); 2613 kfree(arg); 2614 arg = NULL; 2615 if (unlikely(rc)) { 2616 goto free_opt; 2617 } 2618 } else { 2619 if (!first) { // copy with preceding comma 2620 from--; 2621 len++; 2622 } 2623 if (to != from) 2624 memmove(to, from, len); 2625 to += len; 2626 first = false; 2627 } 2628 if (!from[len]) 2629 break; 2630 from += len + 1; 2631 } 2632 *to = '\0'; 2633 return 0; 2634 2635 free_opt: 2636 if (*mnt_opts) { 2637 selinux_free_mnt_opts(*mnt_opts); 2638 *mnt_opts = NULL; 2639 } 2640 return rc; 2641 } 2642 2643 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2644 { 2645 struct selinux_mnt_opts *opts = mnt_opts; 2646 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2647 2648 /* 2649 * Superblock not initialized (i.e. no options) - reject if any 2650 * options specified, otherwise accept. 2651 */ 2652 if (!(sbsec->flags & SE_SBINITIALIZED)) 2653 return opts ? 1 : 0; 2654 2655 /* 2656 * Superblock initialized and no options specified - reject if 2657 * superblock has any options set, otherwise accept. 2658 */ 2659 if (!opts) 2660 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2661 2662 if (opts->fscontext_sid) { 2663 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2664 opts->fscontext_sid)) 2665 return 1; 2666 } 2667 if (opts->context_sid) { 2668 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2669 opts->context_sid)) 2670 return 1; 2671 } 2672 if (opts->rootcontext_sid) { 2673 struct inode_security_struct *root_isec; 2674 2675 root_isec = backing_inode_security(sb->s_root); 2676 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2677 opts->rootcontext_sid)) 2678 return 1; 2679 } 2680 if (opts->defcontext_sid) { 2681 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2682 opts->defcontext_sid)) 2683 return 1; 2684 } 2685 return 0; 2686 } 2687 2688 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2689 { 2690 struct selinux_mnt_opts *opts = mnt_opts; 2691 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2692 2693 if (!(sbsec->flags & SE_SBINITIALIZED)) 2694 return 0; 2695 2696 if (!opts) 2697 return 0; 2698 2699 if (opts->fscontext_sid) { 2700 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2701 opts->fscontext_sid)) 2702 goto out_bad_option; 2703 } 2704 if (opts->context_sid) { 2705 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2706 opts->context_sid)) 2707 goto out_bad_option; 2708 } 2709 if (opts->rootcontext_sid) { 2710 struct inode_security_struct *root_isec; 2711 root_isec = backing_inode_security(sb->s_root); 2712 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2713 opts->rootcontext_sid)) 2714 goto out_bad_option; 2715 } 2716 if (opts->defcontext_sid) { 2717 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2718 opts->defcontext_sid)) 2719 goto out_bad_option; 2720 } 2721 return 0; 2722 2723 out_bad_option: 2724 pr_warn("SELinux: unable to change security options " 2725 "during remount (dev %s, type=%s)\n", sb->s_id, 2726 sb->s_type->name); 2727 return -EINVAL; 2728 } 2729 2730 static int selinux_sb_kern_mount(const struct super_block *sb) 2731 { 2732 const struct cred *cred = current_cred(); 2733 struct common_audit_data ad; 2734 2735 ad.type = LSM_AUDIT_DATA_DENTRY; 2736 ad.u.dentry = sb->s_root; 2737 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2738 } 2739 2740 static int selinux_sb_statfs(struct dentry *dentry) 2741 { 2742 const struct cred *cred = current_cred(); 2743 struct common_audit_data ad; 2744 2745 ad.type = LSM_AUDIT_DATA_DENTRY; 2746 ad.u.dentry = dentry->d_sb->s_root; 2747 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2748 } 2749 2750 static int selinux_mount(const char *dev_name, 2751 const struct path *path, 2752 const char *type, 2753 unsigned long flags, 2754 void *data) 2755 { 2756 const struct cred *cred = current_cred(); 2757 2758 if (flags & MS_REMOUNT) 2759 return superblock_has_perm(cred, path->dentry->d_sb, 2760 FILESYSTEM__REMOUNT, NULL); 2761 else 2762 return path_has_perm(cred, path, FILE__MOUNTON); 2763 } 2764 2765 static int selinux_move_mount(const struct path *from_path, 2766 const struct path *to_path) 2767 { 2768 const struct cred *cred = current_cred(); 2769 2770 return path_has_perm(cred, to_path, FILE__MOUNTON); 2771 } 2772 2773 static int selinux_umount(struct vfsmount *mnt, int flags) 2774 { 2775 const struct cred *cred = current_cred(); 2776 2777 return superblock_has_perm(cred, mnt->mnt_sb, 2778 FILESYSTEM__UNMOUNT, NULL); 2779 } 2780 2781 static int selinux_fs_context_submount(struct fs_context *fc, 2782 struct super_block *reference) 2783 { 2784 const struct superblock_security_struct *sbsec = selinux_superblock(reference); 2785 struct selinux_mnt_opts *opts; 2786 2787 /* 2788 * Ensure that fc->security remains NULL when no options are set 2789 * as expected by selinux_set_mnt_opts(). 2790 */ 2791 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) 2792 return 0; 2793 2794 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 2795 if (!opts) 2796 return -ENOMEM; 2797 2798 if (sbsec->flags & FSCONTEXT_MNT) 2799 opts->fscontext_sid = sbsec->sid; 2800 if (sbsec->flags & CONTEXT_MNT) 2801 opts->context_sid = sbsec->mntpoint_sid; 2802 if (sbsec->flags & DEFCONTEXT_MNT) 2803 opts->defcontext_sid = sbsec->def_sid; 2804 fc->security = opts; 2805 return 0; 2806 } 2807 2808 static int selinux_fs_context_dup(struct fs_context *fc, 2809 struct fs_context *src_fc) 2810 { 2811 const struct selinux_mnt_opts *src = src_fc->security; 2812 2813 if (!src) 2814 return 0; 2815 2816 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); 2817 return fc->security ? 0 : -ENOMEM; 2818 } 2819 2820 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2821 fsparam_string(CONTEXT_STR, Opt_context), 2822 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2823 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2824 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2825 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2826 {} 2827 }; 2828 2829 static int selinux_fs_context_parse_param(struct fs_context *fc, 2830 struct fs_parameter *param) 2831 { 2832 struct fs_parse_result result; 2833 int opt; 2834 2835 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2836 if (opt < 0) 2837 return opt; 2838 2839 return selinux_add_opt(opt, param->string, &fc->security); 2840 } 2841 2842 /* inode security operations */ 2843 2844 static int selinux_inode_alloc_security(struct inode *inode) 2845 { 2846 struct inode_security_struct *isec = selinux_inode(inode); 2847 u32 sid = current_sid(); 2848 2849 spin_lock_init(&isec->lock); 2850 INIT_LIST_HEAD(&isec->list); 2851 isec->inode = inode; 2852 isec->sid = SECINITSID_UNLABELED; 2853 isec->sclass = SECCLASS_FILE; 2854 isec->task_sid = sid; 2855 isec->initialized = LABEL_INVALID; 2856 2857 return 0; 2858 } 2859 2860 static void selinux_inode_free_security(struct inode *inode) 2861 { 2862 inode_free_security(inode); 2863 } 2864 2865 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2866 const struct qstr *name, 2867 const char **xattr_name, void **ctx, 2868 u32 *ctxlen) 2869 { 2870 u32 newsid; 2871 int rc; 2872 2873 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2874 d_inode(dentry->d_parent), name, 2875 inode_mode_to_security_class(mode), 2876 &newsid); 2877 if (rc) 2878 return rc; 2879 2880 if (xattr_name) 2881 *xattr_name = XATTR_NAME_SELINUX; 2882 2883 return security_sid_to_context(newsid, (char **)ctx, 2884 ctxlen); 2885 } 2886 2887 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2888 struct qstr *name, 2889 const struct cred *old, 2890 struct cred *new) 2891 { 2892 u32 newsid; 2893 int rc; 2894 struct task_security_struct *tsec; 2895 2896 rc = selinux_determine_inode_label(selinux_cred(old), 2897 d_inode(dentry->d_parent), name, 2898 inode_mode_to_security_class(mode), 2899 &newsid); 2900 if (rc) 2901 return rc; 2902 2903 tsec = selinux_cred(new); 2904 tsec->create_sid = newsid; 2905 return 0; 2906 } 2907 2908 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2909 const struct qstr *qstr, 2910 struct xattr *xattrs, int *xattr_count) 2911 { 2912 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2913 struct superblock_security_struct *sbsec; 2914 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); 2915 u32 newsid, clen; 2916 u16 newsclass; 2917 int rc; 2918 char *context; 2919 2920 sbsec = selinux_superblock(dir->i_sb); 2921 2922 newsid = tsec->create_sid; 2923 newsclass = inode_mode_to_security_class(inode->i_mode); 2924 rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid); 2925 if (rc) 2926 return rc; 2927 2928 /* Possibly defer initialization to selinux_complete_init. */ 2929 if (sbsec->flags & SE_SBINITIALIZED) { 2930 struct inode_security_struct *isec = selinux_inode(inode); 2931 isec->sclass = newsclass; 2932 isec->sid = newsid; 2933 isec->initialized = LABEL_INITIALIZED; 2934 } 2935 2936 if (!selinux_initialized() || 2937 !(sbsec->flags & SBLABEL_MNT)) 2938 return -EOPNOTSUPP; 2939 2940 if (xattr) { 2941 rc = security_sid_to_context_force(newsid, 2942 &context, &clen); 2943 if (rc) 2944 return rc; 2945 xattr->value = context; 2946 xattr->value_len = clen; 2947 xattr->name = XATTR_SELINUX_SUFFIX; 2948 } 2949 2950 return 0; 2951 } 2952 2953 static int selinux_inode_init_security_anon(struct inode *inode, 2954 const struct qstr *name, 2955 const struct inode *context_inode) 2956 { 2957 u32 sid = current_sid(); 2958 struct common_audit_data ad; 2959 struct inode_security_struct *isec; 2960 int rc; 2961 2962 if (unlikely(!selinux_initialized())) 2963 return 0; 2964 2965 isec = selinux_inode(inode); 2966 2967 /* 2968 * We only get here once per ephemeral inode. The inode has 2969 * been initialized via inode_alloc_security but is otherwise 2970 * untouched. 2971 */ 2972 2973 if (context_inode) { 2974 struct inode_security_struct *context_isec = 2975 selinux_inode(context_inode); 2976 if (context_isec->initialized != LABEL_INITIALIZED) { 2977 pr_err("SELinux: context_inode is not initialized\n"); 2978 return -EACCES; 2979 } 2980 2981 isec->sclass = context_isec->sclass; 2982 isec->sid = context_isec->sid; 2983 } else { 2984 isec->sclass = SECCLASS_ANON_INODE; 2985 rc = security_transition_sid( 2986 sid, sid, 2987 isec->sclass, name, &isec->sid); 2988 if (rc) 2989 return rc; 2990 } 2991 2992 isec->initialized = LABEL_INITIALIZED; 2993 /* 2994 * Now that we've initialized security, check whether we're 2995 * allowed to actually create this type of anonymous inode. 2996 */ 2997 2998 ad.type = LSM_AUDIT_DATA_ANONINODE; 2999 ad.u.anonclass = name ? (const char *)name->name : "?"; 3000 3001 return avc_has_perm(sid, 3002 isec->sid, 3003 isec->sclass, 3004 FILE__CREATE, 3005 &ad); 3006 } 3007 3008 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3009 { 3010 return may_create(dir, dentry, SECCLASS_FILE); 3011 } 3012 3013 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3014 { 3015 return may_link(dir, old_dentry, MAY_LINK); 3016 } 3017 3018 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3019 { 3020 return may_link(dir, dentry, MAY_UNLINK); 3021 } 3022 3023 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3024 { 3025 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3026 } 3027 3028 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3029 { 3030 return may_create(dir, dentry, SECCLASS_DIR); 3031 } 3032 3033 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3034 { 3035 return may_link(dir, dentry, MAY_RMDIR); 3036 } 3037 3038 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3039 { 3040 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3041 } 3042 3043 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3044 struct inode *new_inode, struct dentry *new_dentry) 3045 { 3046 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3047 } 3048 3049 static int selinux_inode_readlink(struct dentry *dentry) 3050 { 3051 const struct cred *cred = current_cred(); 3052 3053 return dentry_has_perm(cred, dentry, FILE__READ); 3054 } 3055 3056 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3057 bool rcu) 3058 { 3059 struct common_audit_data ad; 3060 struct inode_security_struct *isec; 3061 u32 sid = current_sid(); 3062 3063 ad.type = LSM_AUDIT_DATA_DENTRY; 3064 ad.u.dentry = dentry; 3065 isec = inode_security_rcu(inode, rcu); 3066 if (IS_ERR(isec)) 3067 return PTR_ERR(isec); 3068 3069 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); 3070 } 3071 3072 static noinline int audit_inode_permission(struct inode *inode, 3073 u32 perms, u32 audited, u32 denied, 3074 int result) 3075 { 3076 struct common_audit_data ad; 3077 struct inode_security_struct *isec = selinux_inode(inode); 3078 3079 ad.type = LSM_AUDIT_DATA_INODE; 3080 ad.u.inode = inode; 3081 3082 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3083 audited, denied, result, &ad); 3084 } 3085 3086 static int selinux_inode_permission(struct inode *inode, int mask) 3087 { 3088 u32 perms; 3089 bool from_access; 3090 bool no_block = mask & MAY_NOT_BLOCK; 3091 struct inode_security_struct *isec; 3092 u32 sid = current_sid(); 3093 struct av_decision avd; 3094 int rc, rc2; 3095 u32 audited, denied; 3096 3097 from_access = mask & MAY_ACCESS; 3098 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3099 3100 /* No permission to check. Existence test. */ 3101 if (!mask) 3102 return 0; 3103 3104 if (unlikely(IS_PRIVATE(inode))) 3105 return 0; 3106 3107 perms = file_mask_to_av(inode->i_mode, mask); 3108 3109 isec = inode_security_rcu(inode, no_block); 3110 if (IS_ERR(isec)) 3111 return PTR_ERR(isec); 3112 3113 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, 3114 &avd); 3115 audited = avc_audit_required(perms, &avd, rc, 3116 from_access ? FILE__AUDIT_ACCESS : 0, 3117 &denied); 3118 if (likely(!audited)) 3119 return rc; 3120 3121 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3122 if (rc2) 3123 return rc2; 3124 return rc; 3125 } 3126 3127 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 3128 struct iattr *iattr) 3129 { 3130 const struct cred *cred = current_cred(); 3131 struct inode *inode = d_backing_inode(dentry); 3132 unsigned int ia_valid = iattr->ia_valid; 3133 __u32 av = FILE__WRITE; 3134 3135 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3136 if (ia_valid & ATTR_FORCE) { 3137 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3138 ATTR_FORCE); 3139 if (!ia_valid) 3140 return 0; 3141 } 3142 3143 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3144 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3145 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3146 3147 if (selinux_policycap_openperm() && 3148 inode->i_sb->s_magic != SOCKFS_MAGIC && 3149 (ia_valid & ATTR_SIZE) && 3150 !(ia_valid & ATTR_FILE)) 3151 av |= FILE__OPEN; 3152 3153 return dentry_has_perm(cred, dentry, av); 3154 } 3155 3156 static int selinux_inode_getattr(const struct path *path) 3157 { 3158 return path_has_perm(current_cred(), path, FILE__GETATTR); 3159 } 3160 3161 static bool has_cap_mac_admin(bool audit) 3162 { 3163 const struct cred *cred = current_cred(); 3164 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3165 3166 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3167 return false; 3168 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3169 return false; 3170 return true; 3171 } 3172 3173 /** 3174 * selinux_inode_xattr_skipcap - Skip the xattr capability checks? 3175 * @name: name of the xattr 3176 * 3177 * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs 3178 * named @name; the LSM layer should avoid enforcing any traditional 3179 * capability based access controls on this xattr. Returns 0 to indicate that 3180 * SELinux does not "own" the access control rights to xattrs named @name and is 3181 * deferring to the LSM layer for further access controls, including capability 3182 * based controls. 3183 */ 3184 static int selinux_inode_xattr_skipcap(const char *name) 3185 { 3186 /* require capability check if not a selinux xattr */ 3187 return !strcmp(name, XATTR_NAME_SELINUX); 3188 } 3189 3190 static int selinux_inode_setxattr(struct mnt_idmap *idmap, 3191 struct dentry *dentry, const char *name, 3192 const void *value, size_t size, int flags) 3193 { 3194 struct inode *inode = d_backing_inode(dentry); 3195 struct inode_security_struct *isec; 3196 struct superblock_security_struct *sbsec; 3197 struct common_audit_data ad; 3198 u32 newsid, sid = current_sid(); 3199 int rc = 0; 3200 3201 /* if not a selinux xattr, only check the ordinary setattr perm */ 3202 if (strcmp(name, XATTR_NAME_SELINUX)) 3203 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3204 3205 if (!selinux_initialized()) 3206 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); 3207 3208 sbsec = selinux_superblock(inode->i_sb); 3209 if (!(sbsec->flags & SBLABEL_MNT)) 3210 return -EOPNOTSUPP; 3211 3212 if (!inode_owner_or_capable(idmap, inode)) 3213 return -EPERM; 3214 3215 ad.type = LSM_AUDIT_DATA_DENTRY; 3216 ad.u.dentry = dentry; 3217 3218 isec = backing_inode_security(dentry); 3219 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3220 FILE__RELABELFROM, &ad); 3221 if (rc) 3222 return rc; 3223 3224 rc = security_context_to_sid(value, size, &newsid, 3225 GFP_KERNEL); 3226 if (rc == -EINVAL) { 3227 if (!has_cap_mac_admin(true)) { 3228 struct audit_buffer *ab; 3229 size_t audit_size; 3230 3231 /* We strip a nul only if it is at the end, otherwise the 3232 * context contains a nul and we should audit that */ 3233 if (value) { 3234 const char *str = value; 3235 3236 if (str[size - 1] == '\0') 3237 audit_size = size - 1; 3238 else 3239 audit_size = size; 3240 } else { 3241 audit_size = 0; 3242 } 3243 ab = audit_log_start(audit_context(), 3244 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3245 if (!ab) 3246 return rc; 3247 audit_log_format(ab, "op=setxattr invalid_context="); 3248 audit_log_n_untrustedstring(ab, value, audit_size); 3249 audit_log_end(ab); 3250 3251 return rc; 3252 } 3253 rc = security_context_to_sid_force(value, 3254 size, &newsid); 3255 } 3256 if (rc) 3257 return rc; 3258 3259 rc = avc_has_perm(sid, newsid, isec->sclass, 3260 FILE__RELABELTO, &ad); 3261 if (rc) 3262 return rc; 3263 3264 rc = security_validate_transition(isec->sid, newsid, 3265 sid, isec->sclass); 3266 if (rc) 3267 return rc; 3268 3269 return avc_has_perm(newsid, 3270 sbsec->sid, 3271 SECCLASS_FILESYSTEM, 3272 FILESYSTEM__ASSOCIATE, 3273 &ad); 3274 } 3275 3276 static int selinux_inode_set_acl(struct mnt_idmap *idmap, 3277 struct dentry *dentry, const char *acl_name, 3278 struct posix_acl *kacl) 3279 { 3280 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3281 } 3282 3283 static int selinux_inode_get_acl(struct mnt_idmap *idmap, 3284 struct dentry *dentry, const char *acl_name) 3285 { 3286 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); 3287 } 3288 3289 static int selinux_inode_remove_acl(struct mnt_idmap *idmap, 3290 struct dentry *dentry, const char *acl_name) 3291 { 3292 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3293 } 3294 3295 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3296 const void *value, size_t size, 3297 int flags) 3298 { 3299 struct inode *inode = d_backing_inode(dentry); 3300 struct inode_security_struct *isec; 3301 u32 newsid; 3302 int rc; 3303 3304 if (strcmp(name, XATTR_NAME_SELINUX)) { 3305 /* Not an attribute we recognize, so nothing to do. */ 3306 return; 3307 } 3308 3309 if (!selinux_initialized()) { 3310 /* If we haven't even been initialized, then we can't validate 3311 * against a policy, so leave the label as invalid. It may 3312 * resolve to a valid label on the next revalidation try if 3313 * we've since initialized. 3314 */ 3315 return; 3316 } 3317 3318 rc = security_context_to_sid_force(value, size, 3319 &newsid); 3320 if (rc) { 3321 pr_err("SELinux: unable to map context to SID" 3322 "for (%s, %lu), rc=%d\n", 3323 inode->i_sb->s_id, inode->i_ino, -rc); 3324 return; 3325 } 3326 3327 isec = backing_inode_security(dentry); 3328 spin_lock(&isec->lock); 3329 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3330 isec->sid = newsid; 3331 isec->initialized = LABEL_INITIALIZED; 3332 spin_unlock(&isec->lock); 3333 } 3334 3335 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3336 { 3337 const struct cred *cred = current_cred(); 3338 3339 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3340 } 3341 3342 static int selinux_inode_listxattr(struct dentry *dentry) 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_removexattr(struct mnt_idmap *idmap, 3350 struct dentry *dentry, const char *name) 3351 { 3352 /* if not a selinux xattr, only check the ordinary setattr perm */ 3353 if (strcmp(name, XATTR_NAME_SELINUX)) 3354 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3355 3356 if (!selinux_initialized()) 3357 return 0; 3358 3359 /* No one is allowed to remove a SELinux security label. 3360 You can change the label, but all data must be labeled. */ 3361 return -EACCES; 3362 } 3363 3364 static int selinux_path_notify(const struct path *path, u64 mask, 3365 unsigned int obj_type) 3366 { 3367 int ret; 3368 u32 perm; 3369 3370 struct common_audit_data ad; 3371 3372 ad.type = LSM_AUDIT_DATA_PATH; 3373 ad.u.path = *path; 3374 3375 /* 3376 * Set permission needed based on the type of mark being set. 3377 * Performs an additional check for sb watches. 3378 */ 3379 switch (obj_type) { 3380 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3381 perm = FILE__WATCH_MOUNT; 3382 break; 3383 case FSNOTIFY_OBJ_TYPE_SB: 3384 perm = FILE__WATCH_SB; 3385 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3386 FILESYSTEM__WATCH, &ad); 3387 if (ret) 3388 return ret; 3389 break; 3390 case FSNOTIFY_OBJ_TYPE_INODE: 3391 perm = FILE__WATCH; 3392 break; 3393 default: 3394 return -EINVAL; 3395 } 3396 3397 /* blocking watches require the file:watch_with_perm permission */ 3398 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3399 perm |= FILE__WATCH_WITH_PERM; 3400 3401 /* watches on read-like events need the file:watch_reads permission */ 3402 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3403 perm |= FILE__WATCH_READS; 3404 3405 return path_has_perm(current_cred(), path, perm); 3406 } 3407 3408 /* 3409 * Copy the inode security context value to the user. 3410 * 3411 * Permission check is handled by selinux_inode_getxattr hook. 3412 */ 3413 static int selinux_inode_getsecurity(struct mnt_idmap *idmap, 3414 struct inode *inode, const char *name, 3415 void **buffer, bool alloc) 3416 { 3417 u32 size; 3418 int error; 3419 char *context = NULL; 3420 struct inode_security_struct *isec; 3421 3422 /* 3423 * If we're not initialized yet, then we can't validate contexts, so 3424 * just let vfs_getxattr fall back to using the on-disk xattr. 3425 */ 3426 if (!selinux_initialized() || 3427 strcmp(name, XATTR_SELINUX_SUFFIX)) 3428 return -EOPNOTSUPP; 3429 3430 /* 3431 * If the caller has CAP_MAC_ADMIN, then get the raw context 3432 * value even if it is not defined by current policy; otherwise, 3433 * use the in-core value under current policy. 3434 * Use the non-auditing forms of the permission checks since 3435 * getxattr may be called by unprivileged processes commonly 3436 * and lack of permission just means that we fall back to the 3437 * in-core context value, not a denial. 3438 */ 3439 isec = inode_security(inode); 3440 if (has_cap_mac_admin(false)) 3441 error = security_sid_to_context_force(isec->sid, &context, 3442 &size); 3443 else 3444 error = security_sid_to_context(isec->sid, 3445 &context, &size); 3446 if (error) 3447 return error; 3448 error = size; 3449 if (alloc) { 3450 *buffer = context; 3451 goto out_nofree; 3452 } 3453 kfree(context); 3454 out_nofree: 3455 return error; 3456 } 3457 3458 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3459 const void *value, size_t size, int flags) 3460 { 3461 struct inode_security_struct *isec = inode_security_novalidate(inode); 3462 struct superblock_security_struct *sbsec; 3463 u32 newsid; 3464 int rc; 3465 3466 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3467 return -EOPNOTSUPP; 3468 3469 sbsec = selinux_superblock(inode->i_sb); 3470 if (!(sbsec->flags & SBLABEL_MNT)) 3471 return -EOPNOTSUPP; 3472 3473 if (!value || !size) 3474 return -EACCES; 3475 3476 rc = security_context_to_sid(value, size, &newsid, 3477 GFP_KERNEL); 3478 if (rc) 3479 return rc; 3480 3481 spin_lock(&isec->lock); 3482 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3483 isec->sid = newsid; 3484 isec->initialized = LABEL_INITIALIZED; 3485 spin_unlock(&isec->lock); 3486 return 0; 3487 } 3488 3489 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3490 { 3491 const int len = sizeof(XATTR_NAME_SELINUX); 3492 3493 if (!selinux_initialized()) 3494 return 0; 3495 3496 if (buffer && len <= buffer_size) 3497 memcpy(buffer, XATTR_NAME_SELINUX, len); 3498 return len; 3499 } 3500 3501 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3502 { 3503 struct inode_security_struct *isec = inode_security_novalidate(inode); 3504 *secid = isec->sid; 3505 } 3506 3507 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3508 { 3509 u32 sid; 3510 struct task_security_struct *tsec; 3511 struct cred *new_creds = *new; 3512 3513 if (new_creds == NULL) { 3514 new_creds = prepare_creds(); 3515 if (!new_creds) 3516 return -ENOMEM; 3517 } 3518 3519 tsec = selinux_cred(new_creds); 3520 /* Get label from overlay inode and set it in create_sid */ 3521 selinux_inode_getsecid(d_inode(src), &sid); 3522 tsec->create_sid = sid; 3523 *new = new_creds; 3524 return 0; 3525 } 3526 3527 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name) 3528 { 3529 /* The copy_up hook above sets the initial context on an inode, but we 3530 * don't then want to overwrite it by blindly copying all the lower 3531 * xattrs up. Instead, filter out SELinux-related xattrs following 3532 * policy load. 3533 */ 3534 if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX)) 3535 return -ECANCELED; /* Discard */ 3536 /* 3537 * Any other attribute apart from SELINUX is not claimed, supported 3538 * by selinux. 3539 */ 3540 return -EOPNOTSUPP; 3541 } 3542 3543 /* kernfs node operations */ 3544 3545 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3546 struct kernfs_node *kn) 3547 { 3548 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3549 u32 parent_sid, newsid, clen; 3550 int rc; 3551 char *context; 3552 3553 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3554 if (rc == -ENODATA) 3555 return 0; 3556 else if (rc < 0) 3557 return rc; 3558 3559 clen = (u32)rc; 3560 context = kmalloc(clen, GFP_KERNEL); 3561 if (!context) 3562 return -ENOMEM; 3563 3564 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3565 if (rc < 0) { 3566 kfree(context); 3567 return rc; 3568 } 3569 3570 rc = security_context_to_sid(context, clen, &parent_sid, 3571 GFP_KERNEL); 3572 kfree(context); 3573 if (rc) 3574 return rc; 3575 3576 if (tsec->create_sid) { 3577 newsid = tsec->create_sid; 3578 } else { 3579 u16 secclass = inode_mode_to_security_class(kn->mode); 3580 struct qstr q; 3581 3582 q.name = kn->name; 3583 q.hash_len = hashlen_string(kn_dir, kn->name); 3584 3585 rc = security_transition_sid(tsec->sid, 3586 parent_sid, secclass, &q, 3587 &newsid); 3588 if (rc) 3589 return rc; 3590 } 3591 3592 rc = security_sid_to_context_force(newsid, 3593 &context, &clen); 3594 if (rc) 3595 return rc; 3596 3597 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3598 XATTR_CREATE); 3599 kfree(context); 3600 return rc; 3601 } 3602 3603 3604 /* file security operations */ 3605 3606 static int selinux_revalidate_file_permission(struct file *file, int mask) 3607 { 3608 const struct cred *cred = current_cred(); 3609 struct inode *inode = file_inode(file); 3610 3611 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3612 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3613 mask |= MAY_APPEND; 3614 3615 return file_has_perm(cred, file, 3616 file_mask_to_av(inode->i_mode, mask)); 3617 } 3618 3619 static int selinux_file_permission(struct file *file, int mask) 3620 { 3621 struct inode *inode = file_inode(file); 3622 struct file_security_struct *fsec = selinux_file(file); 3623 struct inode_security_struct *isec; 3624 u32 sid = current_sid(); 3625 3626 if (!mask) 3627 /* No permission to check. Existence test. */ 3628 return 0; 3629 3630 isec = inode_security(inode); 3631 if (sid == fsec->sid && fsec->isid == isec->sid && 3632 fsec->pseqno == avc_policy_seqno()) 3633 /* No change since file_open check. */ 3634 return 0; 3635 3636 return selinux_revalidate_file_permission(file, mask); 3637 } 3638 3639 static int selinux_file_alloc_security(struct file *file) 3640 { 3641 struct file_security_struct *fsec = selinux_file(file); 3642 u32 sid = current_sid(); 3643 3644 fsec->sid = sid; 3645 fsec->fown_sid = sid; 3646 3647 return 0; 3648 } 3649 3650 /* 3651 * Check whether a task has the ioctl permission and cmd 3652 * operation to an inode. 3653 */ 3654 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3655 u32 requested, u16 cmd) 3656 { 3657 struct common_audit_data ad; 3658 struct file_security_struct *fsec = selinux_file(file); 3659 struct inode *inode = file_inode(file); 3660 struct inode_security_struct *isec; 3661 struct lsm_ioctlop_audit ioctl; 3662 u32 ssid = cred_sid(cred); 3663 int rc; 3664 u8 driver = cmd >> 8; 3665 u8 xperm = cmd & 0xff; 3666 3667 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3668 ad.u.op = &ioctl; 3669 ad.u.op->cmd = cmd; 3670 ad.u.op->path = file->f_path; 3671 3672 if (ssid != fsec->sid) { 3673 rc = avc_has_perm(ssid, fsec->sid, 3674 SECCLASS_FD, 3675 FD__USE, 3676 &ad); 3677 if (rc) 3678 goto out; 3679 } 3680 3681 if (unlikely(IS_PRIVATE(inode))) 3682 return 0; 3683 3684 isec = inode_security(inode); 3685 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3686 requested, driver, xperm, &ad); 3687 out: 3688 return rc; 3689 } 3690 3691 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3692 unsigned long arg) 3693 { 3694 const struct cred *cred = current_cred(); 3695 int error = 0; 3696 3697 switch (cmd) { 3698 case FIONREAD: 3699 case FIBMAP: 3700 case FIGETBSZ: 3701 case FS_IOC_GETFLAGS: 3702 case FS_IOC_GETVERSION: 3703 error = file_has_perm(cred, file, FILE__GETATTR); 3704 break; 3705 3706 case FS_IOC_SETFLAGS: 3707 case FS_IOC_SETVERSION: 3708 error = file_has_perm(cred, file, FILE__SETATTR); 3709 break; 3710 3711 /* sys_ioctl() checks */ 3712 case FIONBIO: 3713 case FIOASYNC: 3714 error = file_has_perm(cred, file, 0); 3715 break; 3716 3717 case KDSKBENT: 3718 case KDSKBSENT: 3719 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3720 CAP_OPT_NONE, true); 3721 break; 3722 3723 case FIOCLEX: 3724 case FIONCLEX: 3725 if (!selinux_policycap_ioctl_skip_cloexec()) 3726 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3727 break; 3728 3729 /* default case assumes that the command will go 3730 * to the file's ioctl() function. 3731 */ 3732 default: 3733 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3734 } 3735 return error; 3736 } 3737 3738 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd, 3739 unsigned long arg) 3740 { 3741 /* 3742 * If we are in a 64-bit kernel running 32-bit userspace, we need to 3743 * make sure we don't compare 32-bit flags to 64-bit flags. 3744 */ 3745 switch (cmd) { 3746 case FS_IOC32_GETFLAGS: 3747 cmd = FS_IOC_GETFLAGS; 3748 break; 3749 case FS_IOC32_SETFLAGS: 3750 cmd = FS_IOC_SETFLAGS; 3751 break; 3752 case FS_IOC32_GETVERSION: 3753 cmd = FS_IOC_GETVERSION; 3754 break; 3755 case FS_IOC32_SETVERSION: 3756 cmd = FS_IOC_SETVERSION; 3757 break; 3758 default: 3759 break; 3760 } 3761 3762 return selinux_file_ioctl(file, cmd, arg); 3763 } 3764 3765 static int default_noexec __ro_after_init; 3766 3767 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3768 { 3769 const struct cred *cred = current_cred(); 3770 u32 sid = cred_sid(cred); 3771 int rc = 0; 3772 3773 if (default_noexec && 3774 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3775 (!shared && (prot & PROT_WRITE)))) { 3776 /* 3777 * We are making executable an anonymous mapping or a 3778 * private file mapping that will also be writable. 3779 * This has an additional check. 3780 */ 3781 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3782 PROCESS__EXECMEM, NULL); 3783 if (rc) 3784 goto error; 3785 } 3786 3787 if (file) { 3788 /* read access is always possible with a mapping */ 3789 u32 av = FILE__READ; 3790 3791 /* write access only matters if the mapping is shared */ 3792 if (shared && (prot & PROT_WRITE)) 3793 av |= FILE__WRITE; 3794 3795 if (prot & PROT_EXEC) 3796 av |= FILE__EXECUTE; 3797 3798 return file_has_perm(cred, file, av); 3799 } 3800 3801 error: 3802 return rc; 3803 } 3804 3805 static int selinux_mmap_addr(unsigned long addr) 3806 { 3807 int rc = 0; 3808 3809 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3810 u32 sid = current_sid(); 3811 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3812 MEMPROTECT__MMAP_ZERO, NULL); 3813 } 3814 3815 return rc; 3816 } 3817 3818 static int selinux_mmap_file(struct file *file, 3819 unsigned long reqprot __always_unused, 3820 unsigned long prot, unsigned long flags) 3821 { 3822 struct common_audit_data ad; 3823 int rc; 3824 3825 if (file) { 3826 ad.type = LSM_AUDIT_DATA_FILE; 3827 ad.u.file = file; 3828 rc = inode_has_perm(current_cred(), file_inode(file), 3829 FILE__MAP, &ad); 3830 if (rc) 3831 return rc; 3832 } 3833 3834 return file_map_prot_check(file, prot, 3835 (flags & MAP_TYPE) == MAP_SHARED); 3836 } 3837 3838 static int selinux_file_mprotect(struct vm_area_struct *vma, 3839 unsigned long reqprot __always_unused, 3840 unsigned long prot) 3841 { 3842 const struct cred *cred = current_cred(); 3843 u32 sid = cred_sid(cred); 3844 3845 if (default_noexec && 3846 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3847 int rc = 0; 3848 if (vma_is_initial_heap(vma)) { 3849 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3850 PROCESS__EXECHEAP, NULL); 3851 } else if (!vma->vm_file && (vma_is_initial_stack(vma) || 3852 vma_is_stack_for_current(vma))) { 3853 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3854 PROCESS__EXECSTACK, NULL); 3855 } else if (vma->vm_file && vma->anon_vma) { 3856 /* 3857 * We are making executable a file mapping that has 3858 * had some COW done. Since pages might have been 3859 * written, check ability to execute the possibly 3860 * modified content. This typically should only 3861 * occur for text relocations. 3862 */ 3863 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3864 } 3865 if (rc) 3866 return rc; 3867 } 3868 3869 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3870 } 3871 3872 static int selinux_file_lock(struct file *file, unsigned int cmd) 3873 { 3874 const struct cred *cred = current_cred(); 3875 3876 return file_has_perm(cred, file, FILE__LOCK); 3877 } 3878 3879 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3880 unsigned long arg) 3881 { 3882 const struct cred *cred = current_cred(); 3883 int err = 0; 3884 3885 switch (cmd) { 3886 case F_SETFL: 3887 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3888 err = file_has_perm(cred, file, FILE__WRITE); 3889 break; 3890 } 3891 fallthrough; 3892 case F_SETOWN: 3893 case F_SETSIG: 3894 case F_GETFL: 3895 case F_GETOWN: 3896 case F_GETSIG: 3897 case F_GETOWNER_UIDS: 3898 /* Just check FD__USE permission */ 3899 err = file_has_perm(cred, file, 0); 3900 break; 3901 case F_GETLK: 3902 case F_SETLK: 3903 case F_SETLKW: 3904 case F_OFD_GETLK: 3905 case F_OFD_SETLK: 3906 case F_OFD_SETLKW: 3907 #if BITS_PER_LONG == 32 3908 case F_GETLK64: 3909 case F_SETLK64: 3910 case F_SETLKW64: 3911 #endif 3912 err = file_has_perm(cred, file, FILE__LOCK); 3913 break; 3914 } 3915 3916 return err; 3917 } 3918 3919 static void selinux_file_set_fowner(struct file *file) 3920 { 3921 struct file_security_struct *fsec; 3922 3923 fsec = selinux_file(file); 3924 fsec->fown_sid = current_sid(); 3925 } 3926 3927 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3928 struct fown_struct *fown, int signum) 3929 { 3930 struct file *file; 3931 u32 sid = task_sid_obj(tsk); 3932 u32 perm; 3933 struct file_security_struct *fsec; 3934 3935 /* struct fown_struct is never outside the context of a struct file */ 3936 file = container_of(fown, struct file, f_owner); 3937 3938 fsec = selinux_file(file); 3939 3940 if (!signum) 3941 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3942 else 3943 perm = signal_to_av(signum); 3944 3945 return avc_has_perm(fsec->fown_sid, sid, 3946 SECCLASS_PROCESS, perm, NULL); 3947 } 3948 3949 static int selinux_file_receive(struct file *file) 3950 { 3951 const struct cred *cred = current_cred(); 3952 3953 return file_has_perm(cred, file, file_to_av(file)); 3954 } 3955 3956 static int selinux_file_open(struct file *file) 3957 { 3958 struct file_security_struct *fsec; 3959 struct inode_security_struct *isec; 3960 3961 fsec = selinux_file(file); 3962 isec = inode_security(file_inode(file)); 3963 /* 3964 * Save inode label and policy sequence number 3965 * at open-time so that selinux_file_permission 3966 * can determine whether revalidation is necessary. 3967 * Task label is already saved in the file security 3968 * struct as its SID. 3969 */ 3970 fsec->isid = isec->sid; 3971 fsec->pseqno = avc_policy_seqno(); 3972 /* 3973 * Since the inode label or policy seqno may have changed 3974 * between the selinux_inode_permission check and the saving 3975 * of state above, recheck that access is still permitted. 3976 * Otherwise, access might never be revalidated against the 3977 * new inode label or new policy. 3978 * This check is not redundant - do not remove. 3979 */ 3980 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3981 } 3982 3983 /* task security operations */ 3984 3985 static int selinux_task_alloc(struct task_struct *task, 3986 unsigned long clone_flags) 3987 { 3988 u32 sid = current_sid(); 3989 3990 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3991 } 3992 3993 /* 3994 * prepare a new set of credentials for modification 3995 */ 3996 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3997 gfp_t gfp) 3998 { 3999 const struct task_security_struct *old_tsec = selinux_cred(old); 4000 struct task_security_struct *tsec = selinux_cred(new); 4001 4002 *tsec = *old_tsec; 4003 return 0; 4004 } 4005 4006 /* 4007 * transfer the SELinux data to a blank set of creds 4008 */ 4009 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 4010 { 4011 const struct task_security_struct *old_tsec = selinux_cred(old); 4012 struct task_security_struct *tsec = selinux_cred(new); 4013 4014 *tsec = *old_tsec; 4015 } 4016 4017 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 4018 { 4019 *secid = cred_sid(c); 4020 } 4021 4022 /* 4023 * set the security data for a kernel service 4024 * - all the creation contexts are set to unlabelled 4025 */ 4026 static int selinux_kernel_act_as(struct cred *new, u32 secid) 4027 { 4028 struct task_security_struct *tsec = selinux_cred(new); 4029 u32 sid = current_sid(); 4030 int ret; 4031 4032 ret = avc_has_perm(sid, secid, 4033 SECCLASS_KERNEL_SERVICE, 4034 KERNEL_SERVICE__USE_AS_OVERRIDE, 4035 NULL); 4036 if (ret == 0) { 4037 tsec->sid = secid; 4038 tsec->create_sid = 0; 4039 tsec->keycreate_sid = 0; 4040 tsec->sockcreate_sid = 0; 4041 } 4042 return ret; 4043 } 4044 4045 /* 4046 * set the file creation context in a security record to the same as the 4047 * objective context of the specified inode 4048 */ 4049 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4050 { 4051 struct inode_security_struct *isec = inode_security(inode); 4052 struct task_security_struct *tsec = selinux_cred(new); 4053 u32 sid = current_sid(); 4054 int ret; 4055 4056 ret = avc_has_perm(sid, isec->sid, 4057 SECCLASS_KERNEL_SERVICE, 4058 KERNEL_SERVICE__CREATE_FILES_AS, 4059 NULL); 4060 4061 if (ret == 0) 4062 tsec->create_sid = isec->sid; 4063 return ret; 4064 } 4065 4066 static int selinux_kernel_module_request(char *kmod_name) 4067 { 4068 struct common_audit_data ad; 4069 4070 ad.type = LSM_AUDIT_DATA_KMOD; 4071 ad.u.kmod_name = kmod_name; 4072 4073 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4074 SYSTEM__MODULE_REQUEST, &ad); 4075 } 4076 4077 static int selinux_kernel_module_from_file(struct file *file) 4078 { 4079 struct common_audit_data ad; 4080 struct inode_security_struct *isec; 4081 struct file_security_struct *fsec; 4082 u32 sid = current_sid(); 4083 int rc; 4084 4085 /* init_module */ 4086 if (file == NULL) 4087 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 4088 SYSTEM__MODULE_LOAD, NULL); 4089 4090 /* finit_module */ 4091 4092 ad.type = LSM_AUDIT_DATA_FILE; 4093 ad.u.file = file; 4094 4095 fsec = selinux_file(file); 4096 if (sid != fsec->sid) { 4097 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4098 if (rc) 4099 return rc; 4100 } 4101 4102 isec = inode_security(file_inode(file)); 4103 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 4104 SYSTEM__MODULE_LOAD, &ad); 4105 } 4106 4107 static int selinux_kernel_read_file(struct file *file, 4108 enum kernel_read_file_id id, 4109 bool contents) 4110 { 4111 int rc = 0; 4112 4113 switch (id) { 4114 case READING_MODULE: 4115 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4116 break; 4117 default: 4118 break; 4119 } 4120 4121 return rc; 4122 } 4123 4124 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4125 { 4126 int rc = 0; 4127 4128 switch (id) { 4129 case LOADING_MODULE: 4130 rc = selinux_kernel_module_from_file(NULL); 4131 break; 4132 default: 4133 break; 4134 } 4135 4136 return rc; 4137 } 4138 4139 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4140 { 4141 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4142 PROCESS__SETPGID, NULL); 4143 } 4144 4145 static int selinux_task_getpgid(struct task_struct *p) 4146 { 4147 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4148 PROCESS__GETPGID, NULL); 4149 } 4150 4151 static int selinux_task_getsid(struct task_struct *p) 4152 { 4153 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4154 PROCESS__GETSESSION, NULL); 4155 } 4156 4157 static void selinux_current_getsecid_subj(u32 *secid) 4158 { 4159 *secid = current_sid(); 4160 } 4161 4162 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) 4163 { 4164 *secid = task_sid_obj(p); 4165 } 4166 4167 static int selinux_task_setnice(struct task_struct *p, int nice) 4168 { 4169 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4170 PROCESS__SETSCHED, NULL); 4171 } 4172 4173 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4174 { 4175 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4176 PROCESS__SETSCHED, NULL); 4177 } 4178 4179 static int selinux_task_getioprio(struct task_struct *p) 4180 { 4181 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4182 PROCESS__GETSCHED, NULL); 4183 } 4184 4185 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4186 unsigned int flags) 4187 { 4188 u32 av = 0; 4189 4190 if (!flags) 4191 return 0; 4192 if (flags & LSM_PRLIMIT_WRITE) 4193 av |= PROCESS__SETRLIMIT; 4194 if (flags & LSM_PRLIMIT_READ) 4195 av |= PROCESS__GETRLIMIT; 4196 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4197 SECCLASS_PROCESS, av, NULL); 4198 } 4199 4200 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4201 struct rlimit *new_rlim) 4202 { 4203 struct rlimit *old_rlim = p->signal->rlim + resource; 4204 4205 /* Control the ability to change the hard limit (whether 4206 lowering or raising it), so that the hard limit can 4207 later be used as a safe reset point for the soft limit 4208 upon context transitions. See selinux_bprm_committing_creds. */ 4209 if (old_rlim->rlim_max != new_rlim->rlim_max) 4210 return avc_has_perm(current_sid(), task_sid_obj(p), 4211 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4212 4213 return 0; 4214 } 4215 4216 static int selinux_task_setscheduler(struct task_struct *p) 4217 { 4218 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4219 PROCESS__SETSCHED, NULL); 4220 } 4221 4222 static int selinux_task_getscheduler(struct task_struct *p) 4223 { 4224 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4225 PROCESS__GETSCHED, NULL); 4226 } 4227 4228 static int selinux_task_movememory(struct task_struct *p) 4229 { 4230 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4231 PROCESS__SETSCHED, NULL); 4232 } 4233 4234 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4235 int sig, const struct cred *cred) 4236 { 4237 u32 secid; 4238 u32 perm; 4239 4240 if (!sig) 4241 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4242 else 4243 perm = signal_to_av(sig); 4244 if (!cred) 4245 secid = current_sid(); 4246 else 4247 secid = cred_sid(cred); 4248 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4249 } 4250 4251 static void selinux_task_to_inode(struct task_struct *p, 4252 struct inode *inode) 4253 { 4254 struct inode_security_struct *isec = selinux_inode(inode); 4255 u32 sid = task_sid_obj(p); 4256 4257 spin_lock(&isec->lock); 4258 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4259 isec->sid = sid; 4260 isec->initialized = LABEL_INITIALIZED; 4261 spin_unlock(&isec->lock); 4262 } 4263 4264 static int selinux_userns_create(const struct cred *cred) 4265 { 4266 u32 sid = current_sid(); 4267 4268 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4269 USER_NAMESPACE__CREATE, NULL); 4270 } 4271 4272 /* Returns error only if unable to parse addresses */ 4273 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4274 struct common_audit_data *ad, u8 *proto) 4275 { 4276 int offset, ihlen, ret = -EINVAL; 4277 struct iphdr _iph, *ih; 4278 4279 offset = skb_network_offset(skb); 4280 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4281 if (ih == NULL) 4282 goto out; 4283 4284 ihlen = ih->ihl * 4; 4285 if (ihlen < sizeof(_iph)) 4286 goto out; 4287 4288 ad->u.net->v4info.saddr = ih->saddr; 4289 ad->u.net->v4info.daddr = ih->daddr; 4290 ret = 0; 4291 4292 if (proto) 4293 *proto = ih->protocol; 4294 4295 switch (ih->protocol) { 4296 case IPPROTO_TCP: { 4297 struct tcphdr _tcph, *th; 4298 4299 if (ntohs(ih->frag_off) & IP_OFFSET) 4300 break; 4301 4302 offset += ihlen; 4303 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4304 if (th == NULL) 4305 break; 4306 4307 ad->u.net->sport = th->source; 4308 ad->u.net->dport = th->dest; 4309 break; 4310 } 4311 4312 case IPPROTO_UDP: { 4313 struct udphdr _udph, *uh; 4314 4315 if (ntohs(ih->frag_off) & IP_OFFSET) 4316 break; 4317 4318 offset += ihlen; 4319 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4320 if (uh == NULL) 4321 break; 4322 4323 ad->u.net->sport = uh->source; 4324 ad->u.net->dport = uh->dest; 4325 break; 4326 } 4327 4328 case IPPROTO_DCCP: { 4329 struct dccp_hdr _dccph, *dh; 4330 4331 if (ntohs(ih->frag_off) & IP_OFFSET) 4332 break; 4333 4334 offset += ihlen; 4335 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4336 if (dh == NULL) 4337 break; 4338 4339 ad->u.net->sport = dh->dccph_sport; 4340 ad->u.net->dport = dh->dccph_dport; 4341 break; 4342 } 4343 4344 #if IS_ENABLED(CONFIG_IP_SCTP) 4345 case IPPROTO_SCTP: { 4346 struct sctphdr _sctph, *sh; 4347 4348 if (ntohs(ih->frag_off) & IP_OFFSET) 4349 break; 4350 4351 offset += ihlen; 4352 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4353 if (sh == NULL) 4354 break; 4355 4356 ad->u.net->sport = sh->source; 4357 ad->u.net->dport = sh->dest; 4358 break; 4359 } 4360 #endif 4361 default: 4362 break; 4363 } 4364 out: 4365 return ret; 4366 } 4367 4368 #if IS_ENABLED(CONFIG_IPV6) 4369 4370 /* Returns error only if unable to parse addresses */ 4371 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4372 struct common_audit_data *ad, u8 *proto) 4373 { 4374 u8 nexthdr; 4375 int ret = -EINVAL, offset; 4376 struct ipv6hdr _ipv6h, *ip6; 4377 __be16 frag_off; 4378 4379 offset = skb_network_offset(skb); 4380 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4381 if (ip6 == NULL) 4382 goto out; 4383 4384 ad->u.net->v6info.saddr = ip6->saddr; 4385 ad->u.net->v6info.daddr = ip6->daddr; 4386 ret = 0; 4387 4388 nexthdr = ip6->nexthdr; 4389 offset += sizeof(_ipv6h); 4390 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4391 if (offset < 0) 4392 goto out; 4393 4394 if (proto) 4395 *proto = nexthdr; 4396 4397 switch (nexthdr) { 4398 case IPPROTO_TCP: { 4399 struct tcphdr _tcph, *th; 4400 4401 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4402 if (th == NULL) 4403 break; 4404 4405 ad->u.net->sport = th->source; 4406 ad->u.net->dport = th->dest; 4407 break; 4408 } 4409 4410 case IPPROTO_UDP: { 4411 struct udphdr _udph, *uh; 4412 4413 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4414 if (uh == NULL) 4415 break; 4416 4417 ad->u.net->sport = uh->source; 4418 ad->u.net->dport = uh->dest; 4419 break; 4420 } 4421 4422 case IPPROTO_DCCP: { 4423 struct dccp_hdr _dccph, *dh; 4424 4425 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4426 if (dh == NULL) 4427 break; 4428 4429 ad->u.net->sport = dh->dccph_sport; 4430 ad->u.net->dport = dh->dccph_dport; 4431 break; 4432 } 4433 4434 #if IS_ENABLED(CONFIG_IP_SCTP) 4435 case IPPROTO_SCTP: { 4436 struct sctphdr _sctph, *sh; 4437 4438 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4439 if (sh == NULL) 4440 break; 4441 4442 ad->u.net->sport = sh->source; 4443 ad->u.net->dport = sh->dest; 4444 break; 4445 } 4446 #endif 4447 /* includes fragments */ 4448 default: 4449 break; 4450 } 4451 out: 4452 return ret; 4453 } 4454 4455 #endif /* IPV6 */ 4456 4457 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4458 char **_addrp, int src, u8 *proto) 4459 { 4460 char *addrp; 4461 int ret; 4462 4463 switch (ad->u.net->family) { 4464 case PF_INET: 4465 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4466 if (ret) 4467 goto parse_error; 4468 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4469 &ad->u.net->v4info.daddr); 4470 goto okay; 4471 4472 #if IS_ENABLED(CONFIG_IPV6) 4473 case PF_INET6: 4474 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4475 if (ret) 4476 goto parse_error; 4477 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4478 &ad->u.net->v6info.daddr); 4479 goto okay; 4480 #endif /* IPV6 */ 4481 default: 4482 addrp = NULL; 4483 goto okay; 4484 } 4485 4486 parse_error: 4487 pr_warn( 4488 "SELinux: failure in selinux_parse_skb()," 4489 " unable to parse packet\n"); 4490 return ret; 4491 4492 okay: 4493 if (_addrp) 4494 *_addrp = addrp; 4495 return 0; 4496 } 4497 4498 /** 4499 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4500 * @skb: the packet 4501 * @family: protocol family 4502 * @sid: the packet's peer label SID 4503 * 4504 * Description: 4505 * Check the various different forms of network peer labeling and determine 4506 * the peer label/SID for the packet; most of the magic actually occurs in 4507 * the security server function security_net_peersid_cmp(). The function 4508 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4509 * or -EACCES if @sid is invalid due to inconsistencies with the different 4510 * peer labels. 4511 * 4512 */ 4513 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4514 { 4515 int err; 4516 u32 xfrm_sid; 4517 u32 nlbl_sid; 4518 u32 nlbl_type; 4519 4520 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4521 if (unlikely(err)) 4522 return -EACCES; 4523 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4524 if (unlikely(err)) 4525 return -EACCES; 4526 4527 err = security_net_peersid_resolve(nlbl_sid, 4528 nlbl_type, xfrm_sid, sid); 4529 if (unlikely(err)) { 4530 pr_warn( 4531 "SELinux: failure in selinux_skb_peerlbl_sid()," 4532 " unable to determine packet's peer label\n"); 4533 return -EACCES; 4534 } 4535 4536 return 0; 4537 } 4538 4539 /** 4540 * selinux_conn_sid - Determine the child socket label for a connection 4541 * @sk_sid: the parent socket's SID 4542 * @skb_sid: the packet's SID 4543 * @conn_sid: the resulting connection SID 4544 * 4545 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4546 * combined with the MLS information from @skb_sid in order to create 4547 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4548 * of @sk_sid. Returns zero on success, negative values on failure. 4549 * 4550 */ 4551 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4552 { 4553 int err = 0; 4554 4555 if (skb_sid != SECSID_NULL) 4556 err = security_sid_mls_copy(sk_sid, skb_sid, 4557 conn_sid); 4558 else 4559 *conn_sid = sk_sid; 4560 4561 return err; 4562 } 4563 4564 /* socket security operations */ 4565 4566 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4567 u16 secclass, u32 *socksid) 4568 { 4569 if (tsec->sockcreate_sid > SECSID_NULL) { 4570 *socksid = tsec->sockcreate_sid; 4571 return 0; 4572 } 4573 4574 return security_transition_sid(tsec->sid, tsec->sid, 4575 secclass, NULL, socksid); 4576 } 4577 4578 static int sock_has_perm(struct sock *sk, u32 perms) 4579 { 4580 struct sk_security_struct *sksec = selinux_sock(sk); 4581 struct common_audit_data ad; 4582 struct lsm_network_audit net; 4583 4584 if (sksec->sid == SECINITSID_KERNEL) 4585 return 0; 4586 4587 /* 4588 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that 4589 * inherited the kernel context from early boot used to be skipped 4590 * here, so preserve that behavior unless the capability is set. 4591 * 4592 * By setting the capability the policy signals that it is ready 4593 * for this quirk to be fixed. Note that sockets created by a kernel 4594 * thread or a usermode helper executed without a transition will 4595 * still be skipped in this check regardless of the policycap 4596 * setting. 4597 */ 4598 if (!selinux_policycap_userspace_initial_context() && 4599 sksec->sid == SECINITSID_INIT) 4600 return 0; 4601 4602 ad_net_init_from_sk(&ad, &net, sk); 4603 4604 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4605 &ad); 4606 } 4607 4608 static int selinux_socket_create(int family, int type, 4609 int protocol, int kern) 4610 { 4611 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4612 u32 newsid; 4613 u16 secclass; 4614 int rc; 4615 4616 if (kern) 4617 return 0; 4618 4619 secclass = socket_type_to_security_class(family, type, protocol); 4620 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4621 if (rc) 4622 return rc; 4623 4624 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4625 } 4626 4627 static int selinux_socket_post_create(struct socket *sock, int family, 4628 int type, int protocol, int kern) 4629 { 4630 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4631 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4632 struct sk_security_struct *sksec; 4633 u16 sclass = socket_type_to_security_class(family, type, protocol); 4634 u32 sid = SECINITSID_KERNEL; 4635 int err = 0; 4636 4637 if (!kern) { 4638 err = socket_sockcreate_sid(tsec, sclass, &sid); 4639 if (err) 4640 return err; 4641 } 4642 4643 isec->sclass = sclass; 4644 isec->sid = sid; 4645 isec->initialized = LABEL_INITIALIZED; 4646 4647 if (sock->sk) { 4648 sksec = selinux_sock(sock->sk); 4649 sksec->sclass = sclass; 4650 sksec->sid = sid; 4651 /* Allows detection of the first association on this socket */ 4652 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4653 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4654 4655 err = selinux_netlbl_socket_post_create(sock->sk, family); 4656 } 4657 4658 return err; 4659 } 4660 4661 static int selinux_socket_socketpair(struct socket *socka, 4662 struct socket *sockb) 4663 { 4664 struct sk_security_struct *sksec_a = selinux_sock(socka->sk); 4665 struct sk_security_struct *sksec_b = selinux_sock(sockb->sk); 4666 4667 sksec_a->peer_sid = sksec_b->sid; 4668 sksec_b->peer_sid = sksec_a->sid; 4669 4670 return 0; 4671 } 4672 4673 /* Range of port numbers used to automatically bind. 4674 Need to determine whether we should perform a name_bind 4675 permission check between the socket and the port number. */ 4676 4677 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4678 { 4679 struct sock *sk = sock->sk; 4680 struct sk_security_struct *sksec = selinux_sock(sk); 4681 u16 family; 4682 int err; 4683 4684 err = sock_has_perm(sk, SOCKET__BIND); 4685 if (err) 4686 goto out; 4687 4688 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4689 family = sk->sk_family; 4690 if (family == PF_INET || family == PF_INET6) { 4691 char *addrp; 4692 struct common_audit_data ad; 4693 struct lsm_network_audit net = {0,}; 4694 struct sockaddr_in *addr4 = NULL; 4695 struct sockaddr_in6 *addr6 = NULL; 4696 u16 family_sa; 4697 unsigned short snum; 4698 u32 sid, node_perm; 4699 4700 /* 4701 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4702 * that validates multiple binding addresses. Because of this 4703 * need to check address->sa_family as it is possible to have 4704 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4705 */ 4706 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4707 return -EINVAL; 4708 family_sa = address->sa_family; 4709 switch (family_sa) { 4710 case AF_UNSPEC: 4711 case AF_INET: 4712 if (addrlen < sizeof(struct sockaddr_in)) 4713 return -EINVAL; 4714 addr4 = (struct sockaddr_in *)address; 4715 if (family_sa == AF_UNSPEC) { 4716 if (family == PF_INET6) { 4717 /* Length check from inet6_bind_sk() */ 4718 if (addrlen < SIN6_LEN_RFC2133) 4719 return -EINVAL; 4720 /* Family check from __inet6_bind() */ 4721 goto err_af; 4722 } 4723 /* see __inet_bind(), we only want to allow 4724 * AF_UNSPEC if the address is INADDR_ANY 4725 */ 4726 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4727 goto err_af; 4728 family_sa = AF_INET; 4729 } 4730 snum = ntohs(addr4->sin_port); 4731 addrp = (char *)&addr4->sin_addr.s_addr; 4732 break; 4733 case AF_INET6: 4734 if (addrlen < SIN6_LEN_RFC2133) 4735 return -EINVAL; 4736 addr6 = (struct sockaddr_in6 *)address; 4737 snum = ntohs(addr6->sin6_port); 4738 addrp = (char *)&addr6->sin6_addr.s6_addr; 4739 break; 4740 default: 4741 goto err_af; 4742 } 4743 4744 ad.type = LSM_AUDIT_DATA_NET; 4745 ad.u.net = &net; 4746 ad.u.net->sport = htons(snum); 4747 ad.u.net->family = family_sa; 4748 4749 if (snum) { 4750 int low, high; 4751 4752 inet_get_local_port_range(sock_net(sk), &low, &high); 4753 4754 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4755 snum < low || snum > high) { 4756 err = sel_netport_sid(sk->sk_protocol, 4757 snum, &sid); 4758 if (err) 4759 goto out; 4760 err = avc_has_perm(sksec->sid, sid, 4761 sksec->sclass, 4762 SOCKET__NAME_BIND, &ad); 4763 if (err) 4764 goto out; 4765 } 4766 } 4767 4768 switch (sksec->sclass) { 4769 case SECCLASS_TCP_SOCKET: 4770 node_perm = TCP_SOCKET__NODE_BIND; 4771 break; 4772 4773 case SECCLASS_UDP_SOCKET: 4774 node_perm = UDP_SOCKET__NODE_BIND; 4775 break; 4776 4777 case SECCLASS_DCCP_SOCKET: 4778 node_perm = DCCP_SOCKET__NODE_BIND; 4779 break; 4780 4781 case SECCLASS_SCTP_SOCKET: 4782 node_perm = SCTP_SOCKET__NODE_BIND; 4783 break; 4784 4785 default: 4786 node_perm = RAWIP_SOCKET__NODE_BIND; 4787 break; 4788 } 4789 4790 err = sel_netnode_sid(addrp, family_sa, &sid); 4791 if (err) 4792 goto out; 4793 4794 if (family_sa == AF_INET) 4795 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4796 else 4797 ad.u.net->v6info.saddr = addr6->sin6_addr; 4798 4799 err = avc_has_perm(sksec->sid, sid, 4800 sksec->sclass, node_perm, &ad); 4801 if (err) 4802 goto out; 4803 } 4804 out: 4805 return err; 4806 err_af: 4807 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4808 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4809 return -EINVAL; 4810 return -EAFNOSUPPORT; 4811 } 4812 4813 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4814 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4815 */ 4816 static int selinux_socket_connect_helper(struct socket *sock, 4817 struct sockaddr *address, int addrlen) 4818 { 4819 struct sock *sk = sock->sk; 4820 struct sk_security_struct *sksec = selinux_sock(sk); 4821 int err; 4822 4823 err = sock_has_perm(sk, SOCKET__CONNECT); 4824 if (err) 4825 return err; 4826 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4827 return -EINVAL; 4828 4829 /* connect(AF_UNSPEC) has special handling, as it is a documented 4830 * way to disconnect the socket 4831 */ 4832 if (address->sa_family == AF_UNSPEC) 4833 return 0; 4834 4835 /* 4836 * If a TCP, DCCP or SCTP socket, check name_connect permission 4837 * for the port. 4838 */ 4839 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4840 sksec->sclass == SECCLASS_DCCP_SOCKET || 4841 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4842 struct common_audit_data ad; 4843 struct lsm_network_audit net = {0,}; 4844 struct sockaddr_in *addr4 = NULL; 4845 struct sockaddr_in6 *addr6 = NULL; 4846 unsigned short snum; 4847 u32 sid, perm; 4848 4849 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4850 * that validates multiple connect addresses. Because of this 4851 * need to check address->sa_family as it is possible to have 4852 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4853 */ 4854 switch (address->sa_family) { 4855 case AF_INET: 4856 addr4 = (struct sockaddr_in *)address; 4857 if (addrlen < sizeof(struct sockaddr_in)) 4858 return -EINVAL; 4859 snum = ntohs(addr4->sin_port); 4860 break; 4861 case AF_INET6: 4862 addr6 = (struct sockaddr_in6 *)address; 4863 if (addrlen < SIN6_LEN_RFC2133) 4864 return -EINVAL; 4865 snum = ntohs(addr6->sin6_port); 4866 break; 4867 default: 4868 /* Note that SCTP services expect -EINVAL, whereas 4869 * others expect -EAFNOSUPPORT. 4870 */ 4871 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4872 return -EINVAL; 4873 else 4874 return -EAFNOSUPPORT; 4875 } 4876 4877 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4878 if (err) 4879 return err; 4880 4881 switch (sksec->sclass) { 4882 case SECCLASS_TCP_SOCKET: 4883 perm = TCP_SOCKET__NAME_CONNECT; 4884 break; 4885 case SECCLASS_DCCP_SOCKET: 4886 perm = DCCP_SOCKET__NAME_CONNECT; 4887 break; 4888 case SECCLASS_SCTP_SOCKET: 4889 perm = SCTP_SOCKET__NAME_CONNECT; 4890 break; 4891 } 4892 4893 ad.type = LSM_AUDIT_DATA_NET; 4894 ad.u.net = &net; 4895 ad.u.net->dport = htons(snum); 4896 ad.u.net->family = address->sa_family; 4897 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4898 if (err) 4899 return err; 4900 } 4901 4902 return 0; 4903 } 4904 4905 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4906 static int selinux_socket_connect(struct socket *sock, 4907 struct sockaddr *address, int addrlen) 4908 { 4909 int err; 4910 struct sock *sk = sock->sk; 4911 4912 err = selinux_socket_connect_helper(sock, address, addrlen); 4913 if (err) 4914 return err; 4915 4916 return selinux_netlbl_socket_connect(sk, address); 4917 } 4918 4919 static int selinux_socket_listen(struct socket *sock, int backlog) 4920 { 4921 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4922 } 4923 4924 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4925 { 4926 int err; 4927 struct inode_security_struct *isec; 4928 struct inode_security_struct *newisec; 4929 u16 sclass; 4930 u32 sid; 4931 4932 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4933 if (err) 4934 return err; 4935 4936 isec = inode_security_novalidate(SOCK_INODE(sock)); 4937 spin_lock(&isec->lock); 4938 sclass = isec->sclass; 4939 sid = isec->sid; 4940 spin_unlock(&isec->lock); 4941 4942 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4943 newisec->sclass = sclass; 4944 newisec->sid = sid; 4945 newisec->initialized = LABEL_INITIALIZED; 4946 4947 return 0; 4948 } 4949 4950 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4951 int size) 4952 { 4953 return sock_has_perm(sock->sk, SOCKET__WRITE); 4954 } 4955 4956 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4957 int size, int flags) 4958 { 4959 return sock_has_perm(sock->sk, SOCKET__READ); 4960 } 4961 4962 static int selinux_socket_getsockname(struct socket *sock) 4963 { 4964 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4965 } 4966 4967 static int selinux_socket_getpeername(struct socket *sock) 4968 { 4969 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4970 } 4971 4972 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4973 { 4974 int err; 4975 4976 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4977 if (err) 4978 return err; 4979 4980 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4981 } 4982 4983 static int selinux_socket_getsockopt(struct socket *sock, int level, 4984 int optname) 4985 { 4986 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4987 } 4988 4989 static int selinux_socket_shutdown(struct socket *sock, int how) 4990 { 4991 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4992 } 4993 4994 static int selinux_socket_unix_stream_connect(struct sock *sock, 4995 struct sock *other, 4996 struct sock *newsk) 4997 { 4998 struct sk_security_struct *sksec_sock = selinux_sock(sock); 4999 struct sk_security_struct *sksec_other = selinux_sock(other); 5000 struct sk_security_struct *sksec_new = selinux_sock(newsk); 5001 struct common_audit_data ad; 5002 struct lsm_network_audit net; 5003 int err; 5004 5005 ad_net_init_from_sk(&ad, &net, other); 5006 5007 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 5008 sksec_other->sclass, 5009 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 5010 if (err) 5011 return err; 5012 5013 /* server child socket */ 5014 sksec_new->peer_sid = sksec_sock->sid; 5015 err = security_sid_mls_copy(sksec_other->sid, 5016 sksec_sock->sid, &sksec_new->sid); 5017 if (err) 5018 return err; 5019 5020 /* connecting socket */ 5021 sksec_sock->peer_sid = sksec_new->sid; 5022 5023 return 0; 5024 } 5025 5026 static int selinux_socket_unix_may_send(struct socket *sock, 5027 struct socket *other) 5028 { 5029 struct sk_security_struct *ssec = selinux_sock(sock->sk); 5030 struct sk_security_struct *osec = selinux_sock(other->sk); 5031 struct common_audit_data ad; 5032 struct lsm_network_audit net; 5033 5034 ad_net_init_from_sk(&ad, &net, other->sk); 5035 5036 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 5037 &ad); 5038 } 5039 5040 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 5041 char *addrp, u16 family, u32 peer_sid, 5042 struct common_audit_data *ad) 5043 { 5044 int err; 5045 u32 if_sid; 5046 u32 node_sid; 5047 5048 err = sel_netif_sid(ns, ifindex, &if_sid); 5049 if (err) 5050 return err; 5051 err = avc_has_perm(peer_sid, if_sid, 5052 SECCLASS_NETIF, NETIF__INGRESS, ad); 5053 if (err) 5054 return err; 5055 5056 err = sel_netnode_sid(addrp, family, &node_sid); 5057 if (err) 5058 return err; 5059 return avc_has_perm(peer_sid, node_sid, 5060 SECCLASS_NODE, NODE__RECVFROM, ad); 5061 } 5062 5063 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5064 u16 family) 5065 { 5066 int err = 0; 5067 struct sk_security_struct *sksec = selinux_sock(sk); 5068 u32 sk_sid = sksec->sid; 5069 struct common_audit_data ad; 5070 struct lsm_network_audit net; 5071 char *addrp; 5072 5073 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5074 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5075 if (err) 5076 return err; 5077 5078 if (selinux_secmark_enabled()) { 5079 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5080 PACKET__RECV, &ad); 5081 if (err) 5082 return err; 5083 } 5084 5085 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5086 if (err) 5087 return err; 5088 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5089 5090 return err; 5091 } 5092 5093 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5094 { 5095 int err, peerlbl_active, secmark_active; 5096 struct sk_security_struct *sksec = selinux_sock(sk); 5097 u16 family = sk->sk_family; 5098 u32 sk_sid = sksec->sid; 5099 struct common_audit_data ad; 5100 struct lsm_network_audit net; 5101 char *addrp; 5102 5103 if (family != PF_INET && family != PF_INET6) 5104 return 0; 5105 5106 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5107 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5108 family = PF_INET; 5109 5110 /* If any sort of compatibility mode is enabled then handoff processing 5111 * to the selinux_sock_rcv_skb_compat() function to deal with the 5112 * special handling. We do this in an attempt to keep this function 5113 * as fast and as clean as possible. */ 5114 if (!selinux_policycap_netpeer()) 5115 return selinux_sock_rcv_skb_compat(sk, skb, family); 5116 5117 secmark_active = selinux_secmark_enabled(); 5118 peerlbl_active = selinux_peerlbl_enabled(); 5119 if (!secmark_active && !peerlbl_active) 5120 return 0; 5121 5122 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5123 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5124 if (err) 5125 return err; 5126 5127 if (peerlbl_active) { 5128 u32 peer_sid; 5129 5130 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5131 if (err) 5132 return err; 5133 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5134 addrp, family, peer_sid, &ad); 5135 if (err) { 5136 selinux_netlbl_err(skb, family, err, 0); 5137 return err; 5138 } 5139 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5140 PEER__RECV, &ad); 5141 if (err) { 5142 selinux_netlbl_err(skb, family, err, 0); 5143 return err; 5144 } 5145 } 5146 5147 if (secmark_active) { 5148 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5149 PACKET__RECV, &ad); 5150 if (err) 5151 return err; 5152 } 5153 5154 return err; 5155 } 5156 5157 static int selinux_socket_getpeersec_stream(struct socket *sock, 5158 sockptr_t optval, sockptr_t optlen, 5159 unsigned int len) 5160 { 5161 int err = 0; 5162 char *scontext = NULL; 5163 u32 scontext_len; 5164 struct sk_security_struct *sksec = selinux_sock(sock->sk); 5165 u32 peer_sid = SECSID_NULL; 5166 5167 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5168 sksec->sclass == SECCLASS_TCP_SOCKET || 5169 sksec->sclass == SECCLASS_SCTP_SOCKET) 5170 peer_sid = sksec->peer_sid; 5171 if (peer_sid == SECSID_NULL) 5172 return -ENOPROTOOPT; 5173 5174 err = security_sid_to_context(peer_sid, &scontext, 5175 &scontext_len); 5176 if (err) 5177 return err; 5178 if (scontext_len > len) { 5179 err = -ERANGE; 5180 goto out_len; 5181 } 5182 5183 if (copy_to_sockptr(optval, scontext, scontext_len)) 5184 err = -EFAULT; 5185 out_len: 5186 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5187 err = -EFAULT; 5188 kfree(scontext); 5189 return err; 5190 } 5191 5192 static int selinux_socket_getpeersec_dgram(struct socket *sock, 5193 struct sk_buff *skb, u32 *secid) 5194 { 5195 u32 peer_secid = SECSID_NULL; 5196 u16 family; 5197 5198 if (skb && skb->protocol == htons(ETH_P_IP)) 5199 family = PF_INET; 5200 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5201 family = PF_INET6; 5202 else if (sock) 5203 family = sock->sk->sk_family; 5204 else { 5205 *secid = SECSID_NULL; 5206 return -EINVAL; 5207 } 5208 5209 if (sock && family == PF_UNIX) { 5210 struct inode_security_struct *isec; 5211 isec = inode_security_novalidate(SOCK_INODE(sock)); 5212 peer_secid = isec->sid; 5213 } else if (skb) 5214 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5215 5216 *secid = peer_secid; 5217 if (peer_secid == SECSID_NULL) 5218 return -ENOPROTOOPT; 5219 return 0; 5220 } 5221 5222 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5223 { 5224 struct sk_security_struct *sksec = selinux_sock(sk); 5225 5226 sksec->peer_sid = SECINITSID_UNLABELED; 5227 sksec->sid = SECINITSID_UNLABELED; 5228 sksec->sclass = SECCLASS_SOCKET; 5229 selinux_netlbl_sk_security_reset(sksec); 5230 5231 return 0; 5232 } 5233 5234 static void selinux_sk_free_security(struct sock *sk) 5235 { 5236 struct sk_security_struct *sksec = selinux_sock(sk); 5237 5238 selinux_netlbl_sk_security_free(sksec); 5239 } 5240 5241 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5242 { 5243 struct sk_security_struct *sksec = selinux_sock(sk); 5244 struct sk_security_struct *newsksec = selinux_sock(newsk); 5245 5246 newsksec->sid = sksec->sid; 5247 newsksec->peer_sid = sksec->peer_sid; 5248 newsksec->sclass = sksec->sclass; 5249 5250 selinux_netlbl_sk_security_reset(newsksec); 5251 } 5252 5253 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5254 { 5255 if (!sk) 5256 *secid = SECINITSID_ANY_SOCKET; 5257 else { 5258 const struct sk_security_struct *sksec = selinux_sock(sk); 5259 5260 *secid = sksec->sid; 5261 } 5262 } 5263 5264 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5265 { 5266 struct inode_security_struct *isec = 5267 inode_security_novalidate(SOCK_INODE(parent)); 5268 struct sk_security_struct *sksec = selinux_sock(sk); 5269 5270 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5271 sk->sk_family == PF_UNIX) 5272 isec->sid = sksec->sid; 5273 sksec->sclass = isec->sclass; 5274 } 5275 5276 /* 5277 * Determines peer_secid for the asoc and updates socket's peer label 5278 * if it's the first association on the socket. 5279 */ 5280 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5281 struct sk_buff *skb) 5282 { 5283 struct sock *sk = asoc->base.sk; 5284 u16 family = sk->sk_family; 5285 struct sk_security_struct *sksec = selinux_sock(sk); 5286 struct common_audit_data ad; 5287 struct lsm_network_audit net; 5288 int err; 5289 5290 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5291 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5292 family = PF_INET; 5293 5294 if (selinux_peerlbl_enabled()) { 5295 asoc->peer_secid = SECSID_NULL; 5296 5297 /* This will return peer_sid = SECSID_NULL if there are 5298 * no peer labels, see security_net_peersid_resolve(). 5299 */ 5300 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5301 if (err) 5302 return err; 5303 5304 if (asoc->peer_secid == SECSID_NULL) 5305 asoc->peer_secid = SECINITSID_UNLABELED; 5306 } else { 5307 asoc->peer_secid = SECINITSID_UNLABELED; 5308 } 5309 5310 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5311 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5312 5313 /* Here as first association on socket. As the peer SID 5314 * was allowed by peer recv (and the netif/node checks), 5315 * then it is approved by policy and used as the primary 5316 * peer SID for getpeercon(3). 5317 */ 5318 sksec->peer_sid = asoc->peer_secid; 5319 } else if (sksec->peer_sid != asoc->peer_secid) { 5320 /* Other association peer SIDs are checked to enforce 5321 * consistency among the peer SIDs. 5322 */ 5323 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5324 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5325 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5326 &ad); 5327 if (err) 5328 return err; 5329 } 5330 return 0; 5331 } 5332 5333 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5334 * happens on an incoming connect(2), sctp_connectx(3) or 5335 * sctp_sendmsg(3) (with no association already present). 5336 */ 5337 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5338 struct sk_buff *skb) 5339 { 5340 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk); 5341 u32 conn_sid; 5342 int err; 5343 5344 if (!selinux_policycap_extsockclass()) 5345 return 0; 5346 5347 err = selinux_sctp_process_new_assoc(asoc, skb); 5348 if (err) 5349 return err; 5350 5351 /* Compute the MLS component for the connection and store 5352 * the information in asoc. This will be used by SCTP TCP type 5353 * sockets and peeled off connections as they cause a new 5354 * socket to be generated. selinux_sctp_sk_clone() will then 5355 * plug this into the new socket. 5356 */ 5357 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5358 if (err) 5359 return err; 5360 5361 asoc->secid = conn_sid; 5362 5363 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5364 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5365 } 5366 5367 /* Called when SCTP receives a COOKIE ACK chunk as the final 5368 * response to an association request (initited by us). 5369 */ 5370 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5371 struct sk_buff *skb) 5372 { 5373 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk); 5374 5375 if (!selinux_policycap_extsockclass()) 5376 return 0; 5377 5378 /* Inherit secid from the parent socket - this will be picked up 5379 * by selinux_sctp_sk_clone() if the association gets peeled off 5380 * into a new socket. 5381 */ 5382 asoc->secid = sksec->sid; 5383 5384 return selinux_sctp_process_new_assoc(asoc, skb); 5385 } 5386 5387 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5388 * based on their @optname. 5389 */ 5390 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5391 struct sockaddr *address, 5392 int addrlen) 5393 { 5394 int len, err = 0, walk_size = 0; 5395 void *addr_buf; 5396 struct sockaddr *addr; 5397 struct socket *sock; 5398 5399 if (!selinux_policycap_extsockclass()) 5400 return 0; 5401 5402 /* Process one or more addresses that may be IPv4 or IPv6 */ 5403 sock = sk->sk_socket; 5404 addr_buf = address; 5405 5406 while (walk_size < addrlen) { 5407 if (walk_size + sizeof(sa_family_t) > addrlen) 5408 return -EINVAL; 5409 5410 addr = addr_buf; 5411 switch (addr->sa_family) { 5412 case AF_UNSPEC: 5413 case AF_INET: 5414 len = sizeof(struct sockaddr_in); 5415 break; 5416 case AF_INET6: 5417 len = sizeof(struct sockaddr_in6); 5418 break; 5419 default: 5420 return -EINVAL; 5421 } 5422 5423 if (walk_size + len > addrlen) 5424 return -EINVAL; 5425 5426 err = -EINVAL; 5427 switch (optname) { 5428 /* Bind checks */ 5429 case SCTP_PRIMARY_ADDR: 5430 case SCTP_SET_PEER_PRIMARY_ADDR: 5431 case SCTP_SOCKOPT_BINDX_ADD: 5432 err = selinux_socket_bind(sock, addr, len); 5433 break; 5434 /* Connect checks */ 5435 case SCTP_SOCKOPT_CONNECTX: 5436 case SCTP_PARAM_SET_PRIMARY: 5437 case SCTP_PARAM_ADD_IP: 5438 case SCTP_SENDMSG_CONNECT: 5439 err = selinux_socket_connect_helper(sock, addr, len); 5440 if (err) 5441 return err; 5442 5443 /* As selinux_sctp_bind_connect() is called by the 5444 * SCTP protocol layer, the socket is already locked, 5445 * therefore selinux_netlbl_socket_connect_locked() 5446 * is called here. The situations handled are: 5447 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5448 * whenever a new IP address is added or when a new 5449 * primary address is selected. 5450 * Note that an SCTP connect(2) call happens before 5451 * the SCTP protocol layer and is handled via 5452 * selinux_socket_connect(). 5453 */ 5454 err = selinux_netlbl_socket_connect_locked(sk, addr); 5455 break; 5456 } 5457 5458 if (err) 5459 return err; 5460 5461 addr_buf += len; 5462 walk_size += len; 5463 } 5464 5465 return 0; 5466 } 5467 5468 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5469 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5470 struct sock *newsk) 5471 { 5472 struct sk_security_struct *sksec = selinux_sock(sk); 5473 struct sk_security_struct *newsksec = selinux_sock(newsk); 5474 5475 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5476 * the non-sctp clone version. 5477 */ 5478 if (!selinux_policycap_extsockclass()) 5479 return selinux_sk_clone_security(sk, newsk); 5480 5481 newsksec->sid = asoc->secid; 5482 newsksec->peer_sid = asoc->peer_secid; 5483 newsksec->sclass = sksec->sclass; 5484 selinux_netlbl_sctp_sk_clone(sk, newsk); 5485 } 5486 5487 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5488 { 5489 struct sk_security_struct *ssksec = selinux_sock(ssk); 5490 struct sk_security_struct *sksec = selinux_sock(sk); 5491 5492 ssksec->sclass = sksec->sclass; 5493 ssksec->sid = sksec->sid; 5494 5495 /* replace the existing subflow label deleting the existing one 5496 * and re-recreating a new label using the updated context 5497 */ 5498 selinux_netlbl_sk_security_free(ssksec); 5499 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5500 } 5501 5502 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5503 struct request_sock *req) 5504 { 5505 struct sk_security_struct *sksec = selinux_sock(sk); 5506 int err; 5507 u16 family = req->rsk_ops->family; 5508 u32 connsid; 5509 u32 peersid; 5510 5511 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5512 if (err) 5513 return err; 5514 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5515 if (err) 5516 return err; 5517 req->secid = connsid; 5518 req->peer_secid = peersid; 5519 5520 return selinux_netlbl_inet_conn_request(req, family); 5521 } 5522 5523 static void selinux_inet_csk_clone(struct sock *newsk, 5524 const struct request_sock *req) 5525 { 5526 struct sk_security_struct *newsksec = selinux_sock(newsk); 5527 5528 newsksec->sid = req->secid; 5529 newsksec->peer_sid = req->peer_secid; 5530 /* NOTE: Ideally, we should also get the isec->sid for the 5531 new socket in sync, but we don't have the isec available yet. 5532 So we will wait until sock_graft to do it, by which 5533 time it will have been created and available. */ 5534 5535 /* We don't need to take any sort of lock here as we are the only 5536 * thread with access to newsksec */ 5537 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5538 } 5539 5540 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5541 { 5542 u16 family = sk->sk_family; 5543 struct sk_security_struct *sksec = selinux_sock(sk); 5544 5545 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5546 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5547 family = PF_INET; 5548 5549 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5550 } 5551 5552 static int selinux_secmark_relabel_packet(u32 sid) 5553 { 5554 return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO, 5555 NULL); 5556 } 5557 5558 static void selinux_secmark_refcount_inc(void) 5559 { 5560 atomic_inc(&selinux_secmark_refcount); 5561 } 5562 5563 static void selinux_secmark_refcount_dec(void) 5564 { 5565 atomic_dec(&selinux_secmark_refcount); 5566 } 5567 5568 static void selinux_req_classify_flow(const struct request_sock *req, 5569 struct flowi_common *flic) 5570 { 5571 flic->flowic_secid = req->secid; 5572 } 5573 5574 static int selinux_tun_dev_alloc_security(void *security) 5575 { 5576 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5577 5578 tunsec->sid = current_sid(); 5579 return 0; 5580 } 5581 5582 static int selinux_tun_dev_create(void) 5583 { 5584 u32 sid = current_sid(); 5585 5586 /* we aren't taking into account the "sockcreate" SID since the socket 5587 * that is being created here is not a socket in the traditional sense, 5588 * instead it is a private sock, accessible only to the kernel, and 5589 * representing a wide range of network traffic spanning multiple 5590 * connections unlike traditional sockets - check the TUN driver to 5591 * get a better understanding of why this socket is special */ 5592 5593 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5594 NULL); 5595 } 5596 5597 static int selinux_tun_dev_attach_queue(void *security) 5598 { 5599 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5600 5601 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5602 TUN_SOCKET__ATTACH_QUEUE, NULL); 5603 } 5604 5605 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5606 { 5607 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5608 struct sk_security_struct *sksec = selinux_sock(sk); 5609 5610 /* we don't currently perform any NetLabel based labeling here and it 5611 * isn't clear that we would want to do so anyway; while we could apply 5612 * labeling without the support of the TUN user the resulting labeled 5613 * traffic from the other end of the connection would almost certainly 5614 * cause confusion to the TUN user that had no idea network labeling 5615 * protocols were being used */ 5616 5617 sksec->sid = tunsec->sid; 5618 sksec->sclass = SECCLASS_TUN_SOCKET; 5619 5620 return 0; 5621 } 5622 5623 static int selinux_tun_dev_open(void *security) 5624 { 5625 struct tun_security_struct *tunsec = selinux_tun_dev(security); 5626 u32 sid = current_sid(); 5627 int err; 5628 5629 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5630 TUN_SOCKET__RELABELFROM, NULL); 5631 if (err) 5632 return err; 5633 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5634 TUN_SOCKET__RELABELTO, NULL); 5635 if (err) 5636 return err; 5637 tunsec->sid = sid; 5638 5639 return 0; 5640 } 5641 5642 #ifdef CONFIG_NETFILTER 5643 5644 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5645 const struct nf_hook_state *state) 5646 { 5647 int ifindex; 5648 u16 family; 5649 char *addrp; 5650 u32 peer_sid; 5651 struct common_audit_data ad; 5652 struct lsm_network_audit net; 5653 int secmark_active, peerlbl_active; 5654 5655 if (!selinux_policycap_netpeer()) 5656 return NF_ACCEPT; 5657 5658 secmark_active = selinux_secmark_enabled(); 5659 peerlbl_active = selinux_peerlbl_enabled(); 5660 if (!secmark_active && !peerlbl_active) 5661 return NF_ACCEPT; 5662 5663 family = state->pf; 5664 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5665 return NF_DROP; 5666 5667 ifindex = state->in->ifindex; 5668 ad_net_init_from_iif(&ad, &net, ifindex, family); 5669 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5670 return NF_DROP; 5671 5672 if (peerlbl_active) { 5673 int err; 5674 5675 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5676 addrp, family, peer_sid, &ad); 5677 if (err) { 5678 selinux_netlbl_err(skb, family, err, 1); 5679 return NF_DROP; 5680 } 5681 } 5682 5683 if (secmark_active) 5684 if (avc_has_perm(peer_sid, skb->secmark, 5685 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5686 return NF_DROP; 5687 5688 if (netlbl_enabled()) 5689 /* we do this in the FORWARD path and not the POST_ROUTING 5690 * path because we want to make sure we apply the necessary 5691 * labeling before IPsec is applied so we can leverage AH 5692 * protection */ 5693 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5694 return NF_DROP; 5695 5696 return NF_ACCEPT; 5697 } 5698 5699 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5700 const struct nf_hook_state *state) 5701 { 5702 struct sock *sk; 5703 u32 sid; 5704 5705 if (!netlbl_enabled()) 5706 return NF_ACCEPT; 5707 5708 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5709 * because we want to make sure we apply the necessary labeling 5710 * before IPsec is applied so we can leverage AH protection */ 5711 sk = skb->sk; 5712 if (sk) { 5713 struct sk_security_struct *sksec; 5714 5715 if (sk_listener(sk)) 5716 /* if the socket is the listening state then this 5717 * packet is a SYN-ACK packet which means it needs to 5718 * be labeled based on the connection/request_sock and 5719 * not the parent socket. unfortunately, we can't 5720 * lookup the request_sock yet as it isn't queued on 5721 * the parent socket until after the SYN-ACK is sent. 5722 * the "solution" is to simply pass the packet as-is 5723 * as any IP option based labeling should be copied 5724 * from the initial connection request (in the IP 5725 * layer). it is far from ideal, but until we get a 5726 * security label in the packet itself this is the 5727 * best we can do. */ 5728 return NF_ACCEPT; 5729 5730 /* standard practice, label using the parent socket */ 5731 sksec = selinux_sock(sk); 5732 sid = sksec->sid; 5733 } else 5734 sid = SECINITSID_KERNEL; 5735 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5736 return NF_DROP; 5737 5738 return NF_ACCEPT; 5739 } 5740 5741 5742 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5743 const struct nf_hook_state *state) 5744 { 5745 struct sock *sk; 5746 struct sk_security_struct *sksec; 5747 struct common_audit_data ad; 5748 struct lsm_network_audit net; 5749 u8 proto = 0; 5750 5751 sk = skb_to_full_sk(skb); 5752 if (sk == NULL) 5753 return NF_ACCEPT; 5754 sksec = selinux_sock(sk); 5755 5756 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5757 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5758 return NF_DROP; 5759 5760 if (selinux_secmark_enabled()) 5761 if (avc_has_perm(sksec->sid, skb->secmark, 5762 SECCLASS_PACKET, PACKET__SEND, &ad)) 5763 return NF_DROP_ERR(-ECONNREFUSED); 5764 5765 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5766 return NF_DROP_ERR(-ECONNREFUSED); 5767 5768 return NF_ACCEPT; 5769 } 5770 5771 static unsigned int selinux_ip_postroute(void *priv, 5772 struct sk_buff *skb, 5773 const struct nf_hook_state *state) 5774 { 5775 u16 family; 5776 u32 secmark_perm; 5777 u32 peer_sid; 5778 int ifindex; 5779 struct sock *sk; 5780 struct common_audit_data ad; 5781 struct lsm_network_audit net; 5782 char *addrp; 5783 int secmark_active, peerlbl_active; 5784 5785 /* If any sort of compatibility mode is enabled then handoff processing 5786 * to the selinux_ip_postroute_compat() function to deal with the 5787 * special handling. We do this in an attempt to keep this function 5788 * as fast and as clean as possible. */ 5789 if (!selinux_policycap_netpeer()) 5790 return selinux_ip_postroute_compat(skb, state); 5791 5792 secmark_active = selinux_secmark_enabled(); 5793 peerlbl_active = selinux_peerlbl_enabled(); 5794 if (!secmark_active && !peerlbl_active) 5795 return NF_ACCEPT; 5796 5797 sk = skb_to_full_sk(skb); 5798 5799 #ifdef CONFIG_XFRM 5800 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5801 * packet transformation so allow the packet to pass without any checks 5802 * since we'll have another chance to perform access control checks 5803 * when the packet is on it's final way out. 5804 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5805 * is NULL, in this case go ahead and apply access control. 5806 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5807 * TCP listening state we cannot wait until the XFRM processing 5808 * is done as we will miss out on the SA label if we do; 5809 * unfortunately, this means more work, but it is only once per 5810 * connection. */ 5811 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5812 !(sk && sk_listener(sk))) 5813 return NF_ACCEPT; 5814 #endif 5815 5816 family = state->pf; 5817 if (sk == NULL) { 5818 /* Without an associated socket the packet is either coming 5819 * from the kernel or it is being forwarded; check the packet 5820 * to determine which and if the packet is being forwarded 5821 * query the packet directly to determine the security label. */ 5822 if (skb->skb_iif) { 5823 secmark_perm = PACKET__FORWARD_OUT; 5824 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5825 return NF_DROP; 5826 } else { 5827 secmark_perm = PACKET__SEND; 5828 peer_sid = SECINITSID_KERNEL; 5829 } 5830 } else if (sk_listener(sk)) { 5831 /* Locally generated packet but the associated socket is in the 5832 * listening state which means this is a SYN-ACK packet. In 5833 * this particular case the correct security label is assigned 5834 * to the connection/request_sock but unfortunately we can't 5835 * query the request_sock as it isn't queued on the parent 5836 * socket until after the SYN-ACK packet is sent; the only 5837 * viable choice is to regenerate the label like we do in 5838 * selinux_inet_conn_request(). See also selinux_ip_output() 5839 * for similar problems. */ 5840 u32 skb_sid; 5841 struct sk_security_struct *sksec; 5842 5843 sksec = selinux_sock(sk); 5844 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5845 return NF_DROP; 5846 /* At this point, if the returned skb peerlbl is SECSID_NULL 5847 * and the packet has been through at least one XFRM 5848 * transformation then we must be dealing with the "final" 5849 * form of labeled IPsec packet; since we've already applied 5850 * all of our access controls on this packet we can safely 5851 * pass the packet. */ 5852 if (skb_sid == SECSID_NULL) { 5853 switch (family) { 5854 case PF_INET: 5855 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5856 return NF_ACCEPT; 5857 break; 5858 case PF_INET6: 5859 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5860 return NF_ACCEPT; 5861 break; 5862 default: 5863 return NF_DROP_ERR(-ECONNREFUSED); 5864 } 5865 } 5866 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5867 return NF_DROP; 5868 secmark_perm = PACKET__SEND; 5869 } else { 5870 /* Locally generated packet, fetch the security label from the 5871 * associated socket. */ 5872 struct sk_security_struct *sksec = selinux_sock(sk); 5873 peer_sid = sksec->sid; 5874 secmark_perm = PACKET__SEND; 5875 } 5876 5877 ifindex = state->out->ifindex; 5878 ad_net_init_from_iif(&ad, &net, ifindex, family); 5879 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5880 return NF_DROP; 5881 5882 if (secmark_active) 5883 if (avc_has_perm(peer_sid, skb->secmark, 5884 SECCLASS_PACKET, secmark_perm, &ad)) 5885 return NF_DROP_ERR(-ECONNREFUSED); 5886 5887 if (peerlbl_active) { 5888 u32 if_sid; 5889 u32 node_sid; 5890 5891 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5892 return NF_DROP; 5893 if (avc_has_perm(peer_sid, if_sid, 5894 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5895 return NF_DROP_ERR(-ECONNREFUSED); 5896 5897 if (sel_netnode_sid(addrp, family, &node_sid)) 5898 return NF_DROP; 5899 if (avc_has_perm(peer_sid, node_sid, 5900 SECCLASS_NODE, NODE__SENDTO, &ad)) 5901 return NF_DROP_ERR(-ECONNREFUSED); 5902 } 5903 5904 return NF_ACCEPT; 5905 } 5906 #endif /* CONFIG_NETFILTER */ 5907 5908 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5909 { 5910 int rc = 0; 5911 unsigned int msg_len; 5912 unsigned int data_len = skb->len; 5913 unsigned char *data = skb->data; 5914 struct nlmsghdr *nlh; 5915 struct sk_security_struct *sksec = selinux_sock(sk); 5916 u16 sclass = sksec->sclass; 5917 u32 perm; 5918 5919 while (data_len >= nlmsg_total_size(0)) { 5920 nlh = (struct nlmsghdr *)data; 5921 5922 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5923 * users which means we can't reject skb's with bogus 5924 * length fields; our solution is to follow what 5925 * netlink_rcv_skb() does and simply skip processing at 5926 * messages with length fields that are clearly junk 5927 */ 5928 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5929 return 0; 5930 5931 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5932 if (rc == 0) { 5933 rc = sock_has_perm(sk, perm); 5934 if (rc) 5935 return rc; 5936 } else if (rc == -EINVAL) { 5937 /* -EINVAL is a missing msg/perm mapping */ 5938 pr_warn_ratelimited("SELinux: unrecognized netlink" 5939 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5940 " pid=%d comm=%s\n", 5941 sk->sk_protocol, nlh->nlmsg_type, 5942 secclass_map[sclass - 1].name, 5943 task_pid_nr(current), current->comm); 5944 if (enforcing_enabled() && 5945 !security_get_allow_unknown()) 5946 return rc; 5947 rc = 0; 5948 } else if (rc == -ENOENT) { 5949 /* -ENOENT is a missing socket/class mapping, ignore */ 5950 rc = 0; 5951 } else { 5952 return rc; 5953 } 5954 5955 /* move to the next message after applying netlink padding */ 5956 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5957 if (msg_len >= data_len) 5958 return 0; 5959 data_len -= msg_len; 5960 data += msg_len; 5961 } 5962 5963 return rc; 5964 } 5965 5966 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5967 { 5968 isec->sclass = sclass; 5969 isec->sid = current_sid(); 5970 } 5971 5972 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5973 u32 perms) 5974 { 5975 struct ipc_security_struct *isec; 5976 struct common_audit_data ad; 5977 u32 sid = current_sid(); 5978 5979 isec = selinux_ipc(ipc_perms); 5980 5981 ad.type = LSM_AUDIT_DATA_IPC; 5982 ad.u.ipc_id = ipc_perms->key; 5983 5984 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 5985 } 5986 5987 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5988 { 5989 struct msg_security_struct *msec; 5990 5991 msec = selinux_msg_msg(msg); 5992 msec->sid = SECINITSID_UNLABELED; 5993 5994 return 0; 5995 } 5996 5997 /* message queue security operations */ 5998 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 5999 { 6000 struct ipc_security_struct *isec; 6001 struct common_audit_data ad; 6002 u32 sid = current_sid(); 6003 6004 isec = selinux_ipc(msq); 6005 ipc_init_security(isec, SECCLASS_MSGQ); 6006 6007 ad.type = LSM_AUDIT_DATA_IPC; 6008 ad.u.ipc_id = msq->key; 6009 6010 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6011 MSGQ__CREATE, &ad); 6012 } 6013 6014 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 6015 { 6016 struct ipc_security_struct *isec; 6017 struct common_audit_data ad; 6018 u32 sid = current_sid(); 6019 6020 isec = selinux_ipc(msq); 6021 6022 ad.type = LSM_AUDIT_DATA_IPC; 6023 ad.u.ipc_id = msq->key; 6024 6025 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6026 MSGQ__ASSOCIATE, &ad); 6027 } 6028 6029 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 6030 { 6031 u32 perms; 6032 6033 switch (cmd) { 6034 case IPC_INFO: 6035 case MSG_INFO: 6036 /* No specific object, just general system-wide information. */ 6037 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6038 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6039 case IPC_STAT: 6040 case MSG_STAT: 6041 case MSG_STAT_ANY: 6042 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6043 break; 6044 case IPC_SET: 6045 perms = MSGQ__SETATTR; 6046 break; 6047 case IPC_RMID: 6048 perms = MSGQ__DESTROY; 6049 break; 6050 default: 6051 return 0; 6052 } 6053 6054 return ipc_has_perm(msq, perms); 6055 } 6056 6057 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6058 { 6059 struct ipc_security_struct *isec; 6060 struct msg_security_struct *msec; 6061 struct common_audit_data ad; 6062 u32 sid = current_sid(); 6063 int rc; 6064 6065 isec = selinux_ipc(msq); 6066 msec = selinux_msg_msg(msg); 6067 6068 /* 6069 * First time through, need to assign label to the message 6070 */ 6071 if (msec->sid == SECINITSID_UNLABELED) { 6072 /* 6073 * Compute new sid based on current process and 6074 * message queue this message will be stored in 6075 */ 6076 rc = security_transition_sid(sid, isec->sid, 6077 SECCLASS_MSG, NULL, &msec->sid); 6078 if (rc) 6079 return rc; 6080 } 6081 6082 ad.type = LSM_AUDIT_DATA_IPC; 6083 ad.u.ipc_id = msq->key; 6084 6085 /* Can this process write to the queue? */ 6086 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6087 MSGQ__WRITE, &ad); 6088 if (!rc) 6089 /* Can this process send the message */ 6090 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6091 MSG__SEND, &ad); 6092 if (!rc) 6093 /* Can the message be put in the queue? */ 6094 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6095 MSGQ__ENQUEUE, &ad); 6096 6097 return rc; 6098 } 6099 6100 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6101 struct task_struct *target, 6102 long type, int mode) 6103 { 6104 struct ipc_security_struct *isec; 6105 struct msg_security_struct *msec; 6106 struct common_audit_data ad; 6107 u32 sid = task_sid_obj(target); 6108 int rc; 6109 6110 isec = selinux_ipc(msq); 6111 msec = selinux_msg_msg(msg); 6112 6113 ad.type = LSM_AUDIT_DATA_IPC; 6114 ad.u.ipc_id = msq->key; 6115 6116 rc = avc_has_perm(sid, isec->sid, 6117 SECCLASS_MSGQ, MSGQ__READ, &ad); 6118 if (!rc) 6119 rc = avc_has_perm(sid, msec->sid, 6120 SECCLASS_MSG, MSG__RECEIVE, &ad); 6121 return rc; 6122 } 6123 6124 /* Shared Memory security operations */ 6125 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6126 { 6127 struct ipc_security_struct *isec; 6128 struct common_audit_data ad; 6129 u32 sid = current_sid(); 6130 6131 isec = selinux_ipc(shp); 6132 ipc_init_security(isec, SECCLASS_SHM); 6133 6134 ad.type = LSM_AUDIT_DATA_IPC; 6135 ad.u.ipc_id = shp->key; 6136 6137 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6138 SHM__CREATE, &ad); 6139 } 6140 6141 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6142 { 6143 struct ipc_security_struct *isec; 6144 struct common_audit_data ad; 6145 u32 sid = current_sid(); 6146 6147 isec = selinux_ipc(shp); 6148 6149 ad.type = LSM_AUDIT_DATA_IPC; 6150 ad.u.ipc_id = shp->key; 6151 6152 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6153 SHM__ASSOCIATE, &ad); 6154 } 6155 6156 /* Note, at this point, shp is locked down */ 6157 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6158 { 6159 u32 perms; 6160 6161 switch (cmd) { 6162 case IPC_INFO: 6163 case SHM_INFO: 6164 /* No specific object, just general system-wide information. */ 6165 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6166 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6167 case IPC_STAT: 6168 case SHM_STAT: 6169 case SHM_STAT_ANY: 6170 perms = SHM__GETATTR | SHM__ASSOCIATE; 6171 break; 6172 case IPC_SET: 6173 perms = SHM__SETATTR; 6174 break; 6175 case SHM_LOCK: 6176 case SHM_UNLOCK: 6177 perms = SHM__LOCK; 6178 break; 6179 case IPC_RMID: 6180 perms = SHM__DESTROY; 6181 break; 6182 default: 6183 return 0; 6184 } 6185 6186 return ipc_has_perm(shp, perms); 6187 } 6188 6189 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6190 char __user *shmaddr, int shmflg) 6191 { 6192 u32 perms; 6193 6194 if (shmflg & SHM_RDONLY) 6195 perms = SHM__READ; 6196 else 6197 perms = SHM__READ | SHM__WRITE; 6198 6199 return ipc_has_perm(shp, perms); 6200 } 6201 6202 /* Semaphore security operations */ 6203 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6204 { 6205 struct ipc_security_struct *isec; 6206 struct common_audit_data ad; 6207 u32 sid = current_sid(); 6208 6209 isec = selinux_ipc(sma); 6210 ipc_init_security(isec, SECCLASS_SEM); 6211 6212 ad.type = LSM_AUDIT_DATA_IPC; 6213 ad.u.ipc_id = sma->key; 6214 6215 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6216 SEM__CREATE, &ad); 6217 } 6218 6219 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6220 { 6221 struct ipc_security_struct *isec; 6222 struct common_audit_data ad; 6223 u32 sid = current_sid(); 6224 6225 isec = selinux_ipc(sma); 6226 6227 ad.type = LSM_AUDIT_DATA_IPC; 6228 ad.u.ipc_id = sma->key; 6229 6230 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6231 SEM__ASSOCIATE, &ad); 6232 } 6233 6234 /* Note, at this point, sma is locked down */ 6235 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6236 { 6237 int err; 6238 u32 perms; 6239 6240 switch (cmd) { 6241 case IPC_INFO: 6242 case SEM_INFO: 6243 /* No specific object, just general system-wide information. */ 6244 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6245 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6246 case GETPID: 6247 case GETNCNT: 6248 case GETZCNT: 6249 perms = SEM__GETATTR; 6250 break; 6251 case GETVAL: 6252 case GETALL: 6253 perms = SEM__READ; 6254 break; 6255 case SETVAL: 6256 case SETALL: 6257 perms = SEM__WRITE; 6258 break; 6259 case IPC_RMID: 6260 perms = SEM__DESTROY; 6261 break; 6262 case IPC_SET: 6263 perms = SEM__SETATTR; 6264 break; 6265 case IPC_STAT: 6266 case SEM_STAT: 6267 case SEM_STAT_ANY: 6268 perms = SEM__GETATTR | SEM__ASSOCIATE; 6269 break; 6270 default: 6271 return 0; 6272 } 6273 6274 err = ipc_has_perm(sma, perms); 6275 return err; 6276 } 6277 6278 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6279 struct sembuf *sops, unsigned nsops, int alter) 6280 { 6281 u32 perms; 6282 6283 if (alter) 6284 perms = SEM__READ | SEM__WRITE; 6285 else 6286 perms = SEM__READ; 6287 6288 return ipc_has_perm(sma, perms); 6289 } 6290 6291 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6292 { 6293 u32 av = 0; 6294 6295 av = 0; 6296 if (flag & S_IRUGO) 6297 av |= IPC__UNIX_READ; 6298 if (flag & S_IWUGO) 6299 av |= IPC__UNIX_WRITE; 6300 6301 if (av == 0) 6302 return 0; 6303 6304 return ipc_has_perm(ipcp, av); 6305 } 6306 6307 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6308 { 6309 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6310 *secid = isec->sid; 6311 } 6312 6313 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6314 { 6315 if (inode) 6316 inode_doinit_with_dentry(inode, dentry); 6317 } 6318 6319 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p, 6320 char **value) 6321 { 6322 const struct task_security_struct *tsec; 6323 int error; 6324 u32 sid; 6325 u32 len; 6326 6327 rcu_read_lock(); 6328 tsec = selinux_cred(__task_cred(p)); 6329 if (p != current) { 6330 error = avc_has_perm(current_sid(), tsec->sid, 6331 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6332 if (error) 6333 goto err_unlock; 6334 } 6335 switch (attr) { 6336 case LSM_ATTR_CURRENT: 6337 sid = tsec->sid; 6338 break; 6339 case LSM_ATTR_PREV: 6340 sid = tsec->osid; 6341 break; 6342 case LSM_ATTR_EXEC: 6343 sid = tsec->exec_sid; 6344 break; 6345 case LSM_ATTR_FSCREATE: 6346 sid = tsec->create_sid; 6347 break; 6348 case LSM_ATTR_KEYCREATE: 6349 sid = tsec->keycreate_sid; 6350 break; 6351 case LSM_ATTR_SOCKCREATE: 6352 sid = tsec->sockcreate_sid; 6353 break; 6354 default: 6355 error = -EOPNOTSUPP; 6356 goto err_unlock; 6357 } 6358 rcu_read_unlock(); 6359 6360 if (sid == SECSID_NULL) { 6361 *value = NULL; 6362 return 0; 6363 } 6364 6365 error = security_sid_to_context(sid, value, &len); 6366 if (error) 6367 return error; 6368 return len; 6369 6370 err_unlock: 6371 rcu_read_unlock(); 6372 return error; 6373 } 6374 6375 static int selinux_lsm_setattr(u64 attr, void *value, size_t size) 6376 { 6377 struct task_security_struct *tsec; 6378 struct cred *new; 6379 u32 mysid = current_sid(), sid = 0, ptsid; 6380 int error; 6381 char *str = value; 6382 6383 /* 6384 * Basic control over ability to set these attributes at all. 6385 */ 6386 switch (attr) { 6387 case LSM_ATTR_EXEC: 6388 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6389 PROCESS__SETEXEC, NULL); 6390 break; 6391 case LSM_ATTR_FSCREATE: 6392 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6393 PROCESS__SETFSCREATE, NULL); 6394 break; 6395 case LSM_ATTR_KEYCREATE: 6396 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6397 PROCESS__SETKEYCREATE, NULL); 6398 break; 6399 case LSM_ATTR_SOCKCREATE: 6400 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6401 PROCESS__SETSOCKCREATE, NULL); 6402 break; 6403 case LSM_ATTR_CURRENT: 6404 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6405 PROCESS__SETCURRENT, NULL); 6406 break; 6407 default: 6408 error = -EOPNOTSUPP; 6409 break; 6410 } 6411 if (error) 6412 return error; 6413 6414 /* Obtain a SID for the context, if one was specified. */ 6415 if (size && str[0] && str[0] != '\n') { 6416 if (str[size-1] == '\n') { 6417 str[size-1] = 0; 6418 size--; 6419 } 6420 error = security_context_to_sid(value, size, 6421 &sid, GFP_KERNEL); 6422 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) { 6423 if (!has_cap_mac_admin(true)) { 6424 struct audit_buffer *ab; 6425 size_t audit_size; 6426 6427 /* We strip a nul only if it is at the end, 6428 * otherwise the context contains a nul and 6429 * we should audit that */ 6430 if (str[size - 1] == '\0') 6431 audit_size = size - 1; 6432 else 6433 audit_size = size; 6434 ab = audit_log_start(audit_context(), 6435 GFP_ATOMIC, 6436 AUDIT_SELINUX_ERR); 6437 if (!ab) 6438 return error; 6439 audit_log_format(ab, "op=fscreate invalid_context="); 6440 audit_log_n_untrustedstring(ab, value, 6441 audit_size); 6442 audit_log_end(ab); 6443 6444 return error; 6445 } 6446 error = security_context_to_sid_force(value, size, 6447 &sid); 6448 } 6449 if (error) 6450 return error; 6451 } 6452 6453 new = prepare_creds(); 6454 if (!new) 6455 return -ENOMEM; 6456 6457 /* Permission checking based on the specified context is 6458 performed during the actual operation (execve, 6459 open/mkdir/...), when we know the full context of the 6460 operation. See selinux_bprm_creds_for_exec for the execve 6461 checks and may_create for the file creation checks. The 6462 operation will then fail if the context is not permitted. */ 6463 tsec = selinux_cred(new); 6464 if (attr == LSM_ATTR_EXEC) { 6465 tsec->exec_sid = sid; 6466 } else if (attr == LSM_ATTR_FSCREATE) { 6467 tsec->create_sid = sid; 6468 } else if (attr == LSM_ATTR_KEYCREATE) { 6469 if (sid) { 6470 error = avc_has_perm(mysid, sid, 6471 SECCLASS_KEY, KEY__CREATE, NULL); 6472 if (error) 6473 goto abort_change; 6474 } 6475 tsec->keycreate_sid = sid; 6476 } else if (attr == LSM_ATTR_SOCKCREATE) { 6477 tsec->sockcreate_sid = sid; 6478 } else if (attr == LSM_ATTR_CURRENT) { 6479 error = -EINVAL; 6480 if (sid == 0) 6481 goto abort_change; 6482 6483 if (!current_is_single_threaded()) { 6484 error = security_bounded_transition(tsec->sid, sid); 6485 if (error) 6486 goto abort_change; 6487 } 6488 6489 /* Check permissions for the transition. */ 6490 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6491 PROCESS__DYNTRANSITION, NULL); 6492 if (error) 6493 goto abort_change; 6494 6495 /* Check for ptracing, and update the task SID if ok. 6496 Otherwise, leave SID unchanged and fail. */ 6497 ptsid = ptrace_parent_sid(); 6498 if (ptsid != 0) { 6499 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6500 PROCESS__PTRACE, NULL); 6501 if (error) 6502 goto abort_change; 6503 } 6504 6505 tsec->sid = sid; 6506 } else { 6507 error = -EINVAL; 6508 goto abort_change; 6509 } 6510 6511 commit_creds(new); 6512 return size; 6513 6514 abort_change: 6515 abort_creds(new); 6516 return error; 6517 } 6518 6519 /** 6520 * selinux_getselfattr - Get SELinux current task attributes 6521 * @attr: the requested attribute 6522 * @ctx: buffer to receive the result 6523 * @size: buffer size (input), buffer size used (output) 6524 * @flags: unused 6525 * 6526 * Fill the passed user space @ctx with the details of the requested 6527 * attribute. 6528 * 6529 * Returns the number of attributes on success, an error code otherwise. 6530 * There will only ever be one attribute. 6531 */ 6532 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, 6533 u32 *size, u32 flags) 6534 { 6535 int rc; 6536 char *val = NULL; 6537 int val_len; 6538 6539 val_len = selinux_lsm_getattr(attr, current, &val); 6540 if (val_len < 0) 6541 return val_len; 6542 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0); 6543 kfree(val); 6544 return (!rc ? 1 : rc); 6545 } 6546 6547 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx, 6548 u32 size, u32 flags) 6549 { 6550 int rc; 6551 6552 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len); 6553 if (rc > 0) 6554 return 0; 6555 return rc; 6556 } 6557 6558 static int selinux_getprocattr(struct task_struct *p, 6559 const char *name, char **value) 6560 { 6561 unsigned int attr = lsm_name_to_attr(name); 6562 int rc; 6563 6564 if (attr) { 6565 rc = selinux_lsm_getattr(attr, p, value); 6566 if (rc != -EOPNOTSUPP) 6567 return rc; 6568 } 6569 6570 return -EINVAL; 6571 } 6572 6573 static int selinux_setprocattr(const char *name, void *value, size_t size) 6574 { 6575 int attr = lsm_name_to_attr(name); 6576 6577 if (attr) 6578 return selinux_lsm_setattr(attr, value, size); 6579 return -EINVAL; 6580 } 6581 6582 static int selinux_ismaclabel(const char *name) 6583 { 6584 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6585 } 6586 6587 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6588 { 6589 return security_sid_to_context(secid, 6590 secdata, seclen); 6591 } 6592 6593 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6594 { 6595 return security_context_to_sid(secdata, seclen, 6596 secid, GFP_KERNEL); 6597 } 6598 6599 static void selinux_release_secctx(char *secdata, u32 seclen) 6600 { 6601 kfree(secdata); 6602 } 6603 6604 static void selinux_inode_invalidate_secctx(struct inode *inode) 6605 { 6606 struct inode_security_struct *isec = selinux_inode(inode); 6607 6608 spin_lock(&isec->lock); 6609 isec->initialized = LABEL_INVALID; 6610 spin_unlock(&isec->lock); 6611 } 6612 6613 /* 6614 * called with inode->i_mutex locked 6615 */ 6616 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6617 { 6618 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6619 ctx, ctxlen, 0); 6620 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6621 return rc == -EOPNOTSUPP ? 0 : rc; 6622 } 6623 6624 /* 6625 * called with inode->i_mutex locked 6626 */ 6627 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6628 { 6629 return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6630 ctx, ctxlen, 0); 6631 } 6632 6633 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6634 { 6635 int len = 0; 6636 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6637 XATTR_SELINUX_SUFFIX, ctx, true); 6638 if (len < 0) 6639 return len; 6640 *ctxlen = len; 6641 return 0; 6642 } 6643 #ifdef CONFIG_KEYS 6644 6645 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6646 unsigned long flags) 6647 { 6648 const struct task_security_struct *tsec; 6649 struct key_security_struct *ksec = selinux_key(k); 6650 6651 tsec = selinux_cred(cred); 6652 if (tsec->keycreate_sid) 6653 ksec->sid = tsec->keycreate_sid; 6654 else 6655 ksec->sid = tsec->sid; 6656 6657 return 0; 6658 } 6659 6660 static int selinux_key_permission(key_ref_t key_ref, 6661 const struct cred *cred, 6662 enum key_need_perm need_perm) 6663 { 6664 struct key *key; 6665 struct key_security_struct *ksec; 6666 u32 perm, sid; 6667 6668 switch (need_perm) { 6669 case KEY_NEED_VIEW: 6670 perm = KEY__VIEW; 6671 break; 6672 case KEY_NEED_READ: 6673 perm = KEY__READ; 6674 break; 6675 case KEY_NEED_WRITE: 6676 perm = KEY__WRITE; 6677 break; 6678 case KEY_NEED_SEARCH: 6679 perm = KEY__SEARCH; 6680 break; 6681 case KEY_NEED_LINK: 6682 perm = KEY__LINK; 6683 break; 6684 case KEY_NEED_SETATTR: 6685 perm = KEY__SETATTR; 6686 break; 6687 case KEY_NEED_UNLINK: 6688 case KEY_SYSADMIN_OVERRIDE: 6689 case KEY_AUTHTOKEN_OVERRIDE: 6690 case KEY_DEFER_PERM_CHECK: 6691 return 0; 6692 default: 6693 WARN_ON(1); 6694 return -EPERM; 6695 6696 } 6697 6698 sid = cred_sid(cred); 6699 key = key_ref_to_ptr(key_ref); 6700 ksec = selinux_key(key); 6701 6702 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6703 } 6704 6705 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6706 { 6707 struct key_security_struct *ksec = selinux_key(key); 6708 char *context = NULL; 6709 unsigned len; 6710 int rc; 6711 6712 rc = security_sid_to_context(ksec->sid, 6713 &context, &len); 6714 if (!rc) 6715 rc = len; 6716 *_buffer = context; 6717 return rc; 6718 } 6719 6720 #ifdef CONFIG_KEY_NOTIFICATIONS 6721 static int selinux_watch_key(struct key *key) 6722 { 6723 struct key_security_struct *ksec = key->security; 6724 u32 sid = current_sid(); 6725 6726 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6727 } 6728 #endif 6729 #endif 6730 6731 #ifdef CONFIG_SECURITY_INFINIBAND 6732 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6733 { 6734 struct common_audit_data ad; 6735 int err; 6736 u32 sid = 0; 6737 struct ib_security_struct *sec = ib_sec; 6738 struct lsm_ibpkey_audit ibpkey; 6739 6740 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6741 if (err) 6742 return err; 6743 6744 ad.type = LSM_AUDIT_DATA_IBPKEY; 6745 ibpkey.subnet_prefix = subnet_prefix; 6746 ibpkey.pkey = pkey_val; 6747 ad.u.ibpkey = &ibpkey; 6748 return avc_has_perm(sec->sid, sid, 6749 SECCLASS_INFINIBAND_PKEY, 6750 INFINIBAND_PKEY__ACCESS, &ad); 6751 } 6752 6753 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6754 u8 port_num) 6755 { 6756 struct common_audit_data ad; 6757 int err; 6758 u32 sid = 0; 6759 struct ib_security_struct *sec = ib_sec; 6760 struct lsm_ibendport_audit ibendport; 6761 6762 err = security_ib_endport_sid(dev_name, port_num, 6763 &sid); 6764 6765 if (err) 6766 return err; 6767 6768 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6769 ibendport.dev_name = dev_name; 6770 ibendport.port = port_num; 6771 ad.u.ibendport = &ibendport; 6772 return avc_has_perm(sec->sid, sid, 6773 SECCLASS_INFINIBAND_ENDPORT, 6774 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6775 } 6776 6777 static int selinux_ib_alloc_security(void *ib_sec) 6778 { 6779 struct ib_security_struct *sec = selinux_ib(ib_sec); 6780 6781 sec->sid = current_sid(); 6782 return 0; 6783 } 6784 #endif 6785 6786 #ifdef CONFIG_BPF_SYSCALL 6787 static int selinux_bpf(int cmd, union bpf_attr *attr, 6788 unsigned int size) 6789 { 6790 u32 sid = current_sid(); 6791 int ret; 6792 6793 switch (cmd) { 6794 case BPF_MAP_CREATE: 6795 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6796 NULL); 6797 break; 6798 case BPF_PROG_LOAD: 6799 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6800 NULL); 6801 break; 6802 default: 6803 ret = 0; 6804 break; 6805 } 6806 6807 return ret; 6808 } 6809 6810 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6811 { 6812 u32 av = 0; 6813 6814 if (fmode & FMODE_READ) 6815 av |= BPF__MAP_READ; 6816 if (fmode & FMODE_WRITE) 6817 av |= BPF__MAP_WRITE; 6818 return av; 6819 } 6820 6821 /* This function will check the file pass through unix socket or binder to see 6822 * if it is a bpf related object. And apply corresponding checks on the bpf 6823 * object based on the type. The bpf maps and programs, not like other files and 6824 * socket, are using a shared anonymous inode inside the kernel as their inode. 6825 * So checking that inode cannot identify if the process have privilege to 6826 * access the bpf object and that's why we have to add this additional check in 6827 * selinux_file_receive and selinux_binder_transfer_files. 6828 */ 6829 static int bpf_fd_pass(const struct file *file, u32 sid) 6830 { 6831 struct bpf_security_struct *bpfsec; 6832 struct bpf_prog *prog; 6833 struct bpf_map *map; 6834 int ret; 6835 6836 if (file->f_op == &bpf_map_fops) { 6837 map = file->private_data; 6838 bpfsec = map->security; 6839 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6840 bpf_map_fmode_to_av(file->f_mode), NULL); 6841 if (ret) 6842 return ret; 6843 } else if (file->f_op == &bpf_prog_fops) { 6844 prog = file->private_data; 6845 bpfsec = prog->aux->security; 6846 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6847 BPF__PROG_RUN, NULL); 6848 if (ret) 6849 return ret; 6850 } 6851 return 0; 6852 } 6853 6854 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6855 { 6856 u32 sid = current_sid(); 6857 struct bpf_security_struct *bpfsec; 6858 6859 bpfsec = map->security; 6860 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6861 bpf_map_fmode_to_av(fmode), NULL); 6862 } 6863 6864 static int selinux_bpf_prog(struct bpf_prog *prog) 6865 { 6866 u32 sid = current_sid(); 6867 struct bpf_security_struct *bpfsec; 6868 6869 bpfsec = prog->aux->security; 6870 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6871 BPF__PROG_RUN, NULL); 6872 } 6873 6874 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 6875 struct bpf_token *token) 6876 { 6877 struct bpf_security_struct *bpfsec; 6878 6879 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6880 if (!bpfsec) 6881 return -ENOMEM; 6882 6883 bpfsec->sid = current_sid(); 6884 map->security = bpfsec; 6885 6886 return 0; 6887 } 6888 6889 static void selinux_bpf_map_free(struct bpf_map *map) 6890 { 6891 struct bpf_security_struct *bpfsec = map->security; 6892 6893 map->security = NULL; 6894 kfree(bpfsec); 6895 } 6896 6897 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 6898 struct bpf_token *token) 6899 { 6900 struct bpf_security_struct *bpfsec; 6901 6902 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6903 if (!bpfsec) 6904 return -ENOMEM; 6905 6906 bpfsec->sid = current_sid(); 6907 prog->aux->security = bpfsec; 6908 6909 return 0; 6910 } 6911 6912 static void selinux_bpf_prog_free(struct bpf_prog *prog) 6913 { 6914 struct bpf_security_struct *bpfsec = prog->aux->security; 6915 6916 prog->aux->security = NULL; 6917 kfree(bpfsec); 6918 } 6919 6920 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 6921 struct path *path) 6922 { 6923 struct bpf_security_struct *bpfsec; 6924 6925 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6926 if (!bpfsec) 6927 return -ENOMEM; 6928 6929 bpfsec->sid = current_sid(); 6930 token->security = bpfsec; 6931 6932 return 0; 6933 } 6934 6935 static void selinux_bpf_token_free(struct bpf_token *token) 6936 { 6937 struct bpf_security_struct *bpfsec = token->security; 6938 6939 token->security = NULL; 6940 kfree(bpfsec); 6941 } 6942 #endif 6943 6944 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 6945 .lbs_cred = sizeof(struct task_security_struct), 6946 .lbs_file = sizeof(struct file_security_struct), 6947 .lbs_inode = sizeof(struct inode_security_struct), 6948 .lbs_ipc = sizeof(struct ipc_security_struct), 6949 .lbs_key = sizeof(struct key_security_struct), 6950 .lbs_msg_msg = sizeof(struct msg_security_struct), 6951 #ifdef CONFIG_PERF_EVENTS 6952 .lbs_perf_event = sizeof(struct perf_event_security_struct), 6953 #endif 6954 .lbs_sock = sizeof(struct sk_security_struct), 6955 .lbs_superblock = sizeof(struct superblock_security_struct), 6956 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 6957 .lbs_tun_dev = sizeof(struct tun_security_struct), 6958 .lbs_ib = sizeof(struct ib_security_struct), 6959 }; 6960 6961 #ifdef CONFIG_PERF_EVENTS 6962 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 6963 { 6964 u32 requested, sid = current_sid(); 6965 6966 if (type == PERF_SECURITY_OPEN) 6967 requested = PERF_EVENT__OPEN; 6968 else if (type == PERF_SECURITY_CPU) 6969 requested = PERF_EVENT__CPU; 6970 else if (type == PERF_SECURITY_KERNEL) 6971 requested = PERF_EVENT__KERNEL; 6972 else if (type == PERF_SECURITY_TRACEPOINT) 6973 requested = PERF_EVENT__TRACEPOINT; 6974 else 6975 return -EINVAL; 6976 6977 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 6978 requested, NULL); 6979 } 6980 6981 static int selinux_perf_event_alloc(struct perf_event *event) 6982 { 6983 struct perf_event_security_struct *perfsec; 6984 6985 perfsec = selinux_perf_event(event->security); 6986 perfsec->sid = current_sid(); 6987 6988 return 0; 6989 } 6990 6991 static int selinux_perf_event_read(struct perf_event *event) 6992 { 6993 struct perf_event_security_struct *perfsec = event->security; 6994 u32 sid = current_sid(); 6995 6996 return avc_has_perm(sid, perfsec->sid, 6997 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 6998 } 6999 7000 static int selinux_perf_event_write(struct perf_event *event) 7001 { 7002 struct perf_event_security_struct *perfsec = event->security; 7003 u32 sid = current_sid(); 7004 7005 return avc_has_perm(sid, perfsec->sid, 7006 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 7007 } 7008 #endif 7009 7010 #ifdef CONFIG_IO_URING 7011 /** 7012 * selinux_uring_override_creds - check the requested cred override 7013 * @new: the target creds 7014 * 7015 * Check to see if the current task is allowed to override it's credentials 7016 * to service an io_uring operation. 7017 */ 7018 static int selinux_uring_override_creds(const struct cred *new) 7019 { 7020 return avc_has_perm(current_sid(), cred_sid(new), 7021 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 7022 } 7023 7024 /** 7025 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 7026 * 7027 * Check to see if the current task is allowed to create a new io_uring 7028 * kernel polling thread. 7029 */ 7030 static int selinux_uring_sqpoll(void) 7031 { 7032 u32 sid = current_sid(); 7033 7034 return avc_has_perm(sid, sid, 7035 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 7036 } 7037 7038 /** 7039 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 7040 * @ioucmd: the io_uring command structure 7041 * 7042 * Check to see if the current domain is allowed to execute an 7043 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 7044 * 7045 */ 7046 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 7047 { 7048 struct file *file = ioucmd->file; 7049 struct inode *inode = file_inode(file); 7050 struct inode_security_struct *isec = selinux_inode(inode); 7051 struct common_audit_data ad; 7052 7053 ad.type = LSM_AUDIT_DATA_FILE; 7054 ad.u.file = file; 7055 7056 return avc_has_perm(current_sid(), isec->sid, 7057 SECCLASS_IO_URING, IO_URING__CMD, &ad); 7058 } 7059 #endif /* CONFIG_IO_URING */ 7060 7061 static const struct lsm_id selinux_lsmid = { 7062 .name = "selinux", 7063 .id = LSM_ID_SELINUX, 7064 }; 7065 7066 /* 7067 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 7068 * 1. any hooks that don't belong to (2.) or (3.) below, 7069 * 2. hooks that both access structures allocated by other hooks, and allocate 7070 * structures that can be later accessed by other hooks (mostly "cloning" 7071 * hooks), 7072 * 3. hooks that only allocate structures that can be later accessed by other 7073 * hooks ("allocating" hooks). 7074 * 7075 * Please follow block comment delimiters in the list to keep this order. 7076 */ 7077 static struct security_hook_list selinux_hooks[] __ro_after_init = { 7078 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 7079 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 7080 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 7081 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 7082 7083 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 7084 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 7085 LSM_HOOK_INIT(capget, selinux_capget), 7086 LSM_HOOK_INIT(capset, selinux_capset), 7087 LSM_HOOK_INIT(capable, selinux_capable), 7088 LSM_HOOK_INIT(quotactl, selinux_quotactl), 7089 LSM_HOOK_INIT(quota_on, selinux_quota_on), 7090 LSM_HOOK_INIT(syslog, selinux_syslog), 7091 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 7092 7093 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 7094 7095 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 7096 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 7097 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 7098 7099 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 7100 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 7101 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 7102 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 7103 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 7104 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 7105 LSM_HOOK_INIT(sb_mount, selinux_mount), 7106 LSM_HOOK_INIT(sb_umount, selinux_umount), 7107 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7108 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7109 7110 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7111 7112 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7113 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7114 7115 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7116 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7117 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7118 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7119 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7120 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7121 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7122 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7123 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7124 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7125 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7126 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7127 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7128 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7129 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7130 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7131 LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap), 7132 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7133 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7134 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7135 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7136 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7137 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7138 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7139 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7140 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7141 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7142 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7143 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7144 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7145 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7146 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7147 7148 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7149 7150 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7151 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7152 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7153 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat), 7154 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7155 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7156 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7157 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7158 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7159 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7160 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7161 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7162 7163 LSM_HOOK_INIT(file_open, selinux_file_open), 7164 7165 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7166 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7167 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7168 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7169 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7170 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7171 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7172 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7173 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7174 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7175 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7176 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7177 LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), 7178 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), 7179 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7180 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7181 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7182 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7183 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7184 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7185 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7186 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7187 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7188 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7189 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7190 7191 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7192 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7193 7194 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7195 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7196 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7197 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7198 7199 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7200 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7201 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7202 7203 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7204 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7205 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7206 7207 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7208 7209 LSM_HOOK_INIT(getselfattr, selinux_getselfattr), 7210 LSM_HOOK_INIT(setselfattr, selinux_setselfattr), 7211 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7212 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7213 7214 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7215 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7216 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7217 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7218 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7219 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7220 7221 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7222 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7223 7224 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7225 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7226 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7227 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7228 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7229 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7230 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7231 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7232 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7233 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7234 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7235 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7236 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7237 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7238 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7239 LSM_HOOK_INIT(socket_getpeersec_stream, 7240 selinux_socket_getpeersec_stream), 7241 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7242 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7243 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7244 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7245 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7246 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7247 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7248 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7249 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7250 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7251 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7252 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7253 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7254 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7255 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7256 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7257 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7258 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7259 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7260 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7261 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7262 #ifdef CONFIG_SECURITY_INFINIBAND 7263 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7264 LSM_HOOK_INIT(ib_endport_manage_subnet, 7265 selinux_ib_endport_manage_subnet), 7266 #endif 7267 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7268 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7269 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7270 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7271 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7272 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7273 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7274 selinux_xfrm_state_pol_flow_match), 7275 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7276 #endif 7277 7278 #ifdef CONFIG_KEYS 7279 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7280 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7281 #ifdef CONFIG_KEY_NOTIFICATIONS 7282 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7283 #endif 7284 #endif 7285 7286 #ifdef CONFIG_AUDIT 7287 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7288 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7289 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7290 #endif 7291 7292 #ifdef CONFIG_BPF_SYSCALL 7293 LSM_HOOK_INIT(bpf, selinux_bpf), 7294 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7295 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7296 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free), 7297 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free), 7298 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free), 7299 #endif 7300 7301 #ifdef CONFIG_PERF_EVENTS 7302 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7303 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7304 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7305 #endif 7306 7307 #ifdef CONFIG_IO_URING 7308 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7309 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7310 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7311 #endif 7312 7313 /* 7314 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7315 */ 7316 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7317 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7318 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7319 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7320 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7321 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7322 #endif 7323 7324 /* 7325 * PUT "ALLOCATING" HOOKS HERE 7326 */ 7327 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7328 LSM_HOOK_INIT(msg_queue_alloc_security, 7329 selinux_msg_queue_alloc_security), 7330 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7331 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7332 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7333 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7334 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7335 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7336 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7337 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7338 #ifdef CONFIG_SECURITY_INFINIBAND 7339 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7340 #endif 7341 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7342 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7343 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7344 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7345 selinux_xfrm_state_alloc_acquire), 7346 #endif 7347 #ifdef CONFIG_KEYS 7348 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7349 #endif 7350 #ifdef CONFIG_AUDIT 7351 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7352 #endif 7353 #ifdef CONFIG_BPF_SYSCALL 7354 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create), 7355 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load), 7356 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create), 7357 #endif 7358 #ifdef CONFIG_PERF_EVENTS 7359 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7360 #endif 7361 }; 7362 7363 static __init int selinux_init(void) 7364 { 7365 pr_info("SELinux: Initializing.\n"); 7366 7367 memset(&selinux_state, 0, sizeof(selinux_state)); 7368 enforcing_set(selinux_enforcing_boot); 7369 selinux_avc_init(); 7370 mutex_init(&selinux_state.status_lock); 7371 mutex_init(&selinux_state.policy_mutex); 7372 7373 /* Set the security state for the initial task. */ 7374 cred_init_security(); 7375 7376 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7377 if (!default_noexec) 7378 pr_notice("SELinux: virtual memory is executable by default\n"); 7379 7380 avc_init(); 7381 7382 avtab_cache_init(); 7383 7384 ebitmap_cache_init(); 7385 7386 hashtab_cache_init(); 7387 7388 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), 7389 &selinux_lsmid); 7390 7391 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7392 panic("SELinux: Unable to register AVC netcache callback\n"); 7393 7394 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7395 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7396 7397 if (selinux_enforcing_boot) 7398 pr_debug("SELinux: Starting in enforcing mode\n"); 7399 else 7400 pr_debug("SELinux: Starting in permissive mode\n"); 7401 7402 fs_validate_description("selinux", selinux_fs_parameters); 7403 7404 return 0; 7405 } 7406 7407 static void delayed_superblock_init(struct super_block *sb, void *unused) 7408 { 7409 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7410 } 7411 7412 void selinux_complete_init(void) 7413 { 7414 pr_debug("SELinux: Completing initialization.\n"); 7415 7416 /* Set up any superblocks initialized prior to the policy load. */ 7417 pr_debug("SELinux: Setting up existing superblocks.\n"); 7418 iterate_supers(delayed_superblock_init, NULL); 7419 } 7420 7421 /* SELinux requires early initialization in order to label 7422 all processes and objects when they are created. */ 7423 DEFINE_LSM(selinux) = { 7424 .name = "selinux", 7425 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7426 .enabled = &selinux_enabled_boot, 7427 .blobs = &selinux_blob_sizes, 7428 .init = selinux_init, 7429 }; 7430 7431 #if defined(CONFIG_NETFILTER) 7432 static const struct nf_hook_ops selinux_nf_ops[] = { 7433 { 7434 .hook = selinux_ip_postroute, 7435 .pf = NFPROTO_IPV4, 7436 .hooknum = NF_INET_POST_ROUTING, 7437 .priority = NF_IP_PRI_SELINUX_LAST, 7438 }, 7439 { 7440 .hook = selinux_ip_forward, 7441 .pf = NFPROTO_IPV4, 7442 .hooknum = NF_INET_FORWARD, 7443 .priority = NF_IP_PRI_SELINUX_FIRST, 7444 }, 7445 { 7446 .hook = selinux_ip_output, 7447 .pf = NFPROTO_IPV4, 7448 .hooknum = NF_INET_LOCAL_OUT, 7449 .priority = NF_IP_PRI_SELINUX_FIRST, 7450 }, 7451 #if IS_ENABLED(CONFIG_IPV6) 7452 { 7453 .hook = selinux_ip_postroute, 7454 .pf = NFPROTO_IPV6, 7455 .hooknum = NF_INET_POST_ROUTING, 7456 .priority = NF_IP6_PRI_SELINUX_LAST, 7457 }, 7458 { 7459 .hook = selinux_ip_forward, 7460 .pf = NFPROTO_IPV6, 7461 .hooknum = NF_INET_FORWARD, 7462 .priority = NF_IP6_PRI_SELINUX_FIRST, 7463 }, 7464 { 7465 .hook = selinux_ip_output, 7466 .pf = NFPROTO_IPV6, 7467 .hooknum = NF_INET_LOCAL_OUT, 7468 .priority = NF_IP6_PRI_SELINUX_FIRST, 7469 }, 7470 #endif /* IPV6 */ 7471 }; 7472 7473 static int __net_init selinux_nf_register(struct net *net) 7474 { 7475 return nf_register_net_hooks(net, selinux_nf_ops, 7476 ARRAY_SIZE(selinux_nf_ops)); 7477 } 7478 7479 static void __net_exit selinux_nf_unregister(struct net *net) 7480 { 7481 nf_unregister_net_hooks(net, selinux_nf_ops, 7482 ARRAY_SIZE(selinux_nf_ops)); 7483 } 7484 7485 static struct pernet_operations selinux_net_ops = { 7486 .init = selinux_nf_register, 7487 .exit = selinux_nf_unregister, 7488 }; 7489 7490 static int __init selinux_nf_ip_init(void) 7491 { 7492 int err; 7493 7494 if (!selinux_enabled_boot) 7495 return 0; 7496 7497 pr_debug("SELinux: Registering netfilter hooks\n"); 7498 7499 err = register_pernet_subsys(&selinux_net_ops); 7500 if (err) 7501 panic("SELinux: register_pernet_subsys: error %d\n", err); 7502 7503 return 0; 7504 } 7505 __initcall(selinux_nf_ip_init); 7506 #endif /* CONFIG_NETFILTER */ 7507