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