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