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