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/tracehook.h> 29 #include <linux/errno.h> 30 #include <linux/sched/signal.h> 31 #include <linux/sched/task.h> 32 #include <linux/lsm_hooks.h> 33 #include <linux/xattr.h> 34 #include <linux/capability.h> 35 #include <linux/unistd.h> 36 #include <linux/mm.h> 37 #include <linux/mman.h> 38 #include <linux/slab.h> 39 #include <linux/pagemap.h> 40 #include <linux/proc_fs.h> 41 #include <linux/swap.h> 42 #include <linux/spinlock.h> 43 #include <linux/syscalls.h> 44 #include <linux/dcache.h> 45 #include <linux/file.h> 46 #include <linux/fdtable.h> 47 #include <linux/namei.h> 48 #include <linux/mount.h> 49 #include <linux/fs_context.h> 50 #include <linux/fs_parser.h> 51 #include <linux/netfilter_ipv4.h> 52 #include <linux/netfilter_ipv6.h> 53 #include <linux/tty.h> 54 #include <net/icmp.h> 55 #include <net/ip.h> /* for local_port_range[] */ 56 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 57 #include <net/inet_connection_sock.h> 58 #include <net/net_namespace.h> 59 #include <net/netlabel.h> 60 #include <linux/uaccess.h> 61 #include <asm/ioctls.h> 62 #include <linux/atomic.h> 63 #include <linux/bitops.h> 64 #include <linux/interrupt.h> 65 #include <linux/netdevice.h> /* for network interface checks */ 66 #include <net/netlink.h> 67 #include <linux/tcp.h> 68 #include <linux/udp.h> 69 #include <linux/dccp.h> 70 #include <linux/sctp.h> 71 #include <net/sctp/structs.h> 72 #include <linux/quota.h> 73 #include <linux/un.h> /* for Unix socket types */ 74 #include <net/af_unix.h> /* for Unix socket types */ 75 #include <linux/parser.h> 76 #include <linux/nfs_mount.h> 77 #include <net/ipv6.h> 78 #include <linux/hugetlb.h> 79 #include <linux/personality.h> 80 #include <linux/audit.h> 81 #include <linux/string.h> 82 #include <linux/mutex.h> 83 #include <linux/posix-timers.h> 84 #include <linux/syslog.h> 85 #include <linux/user_namespace.h> 86 #include <linux/export.h> 87 #include <linux/msg.h> 88 #include <linux/shm.h> 89 #include <linux/bpf.h> 90 #include <linux/kernfs.h> 91 #include <linux/stringhash.h> /* for hashlen_string() */ 92 #include <uapi/linux/mount.h> 93 #include <linux/fsnotify.h> 94 #include <linux/fanotify.h> 95 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_warn("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 cred *cred = (struct cred *) current->real_cred; 215 struct task_security_struct *tsec; 216 217 tsec = selinux_cred(cred); 218 tsec->osid = tsec->sid = SECINITSID_KERNEL; 219 } 220 221 /* 222 * get the security ID of a set of credentials 223 */ 224 static inline u32 cred_sid(const struct cred *cred) 225 { 226 const struct task_security_struct *tsec; 227 228 tsec = selinux_cred(cred); 229 return tsec->sid; 230 } 231 232 /* 233 * get the subjective security ID of a task 234 */ 235 static inline u32 task_sid_subj(const struct task_struct *task) 236 { 237 u32 sid; 238 239 rcu_read_lock(); 240 sid = cred_sid(rcu_dereference(task->cred)); 241 rcu_read_unlock(); 242 return sid; 243 } 244 245 /* 246 * get the objective security ID of a task 247 */ 248 static inline u32 task_sid_obj(const struct task_struct *task) 249 { 250 u32 sid; 251 252 rcu_read_lock(); 253 sid = cred_sid(__task_cred(task)); 254 rcu_read_unlock(); 255 return sid; 256 } 257 258 /* 259 * get the security ID of a task for use with binder 260 */ 261 static inline u32 task_sid_binder(const struct task_struct *task) 262 { 263 /* 264 * In many case where this function is used we should be using the 265 * task's subjective SID, but we can't reliably access the subjective 266 * creds of a task other than our own so we must use the objective 267 * creds/SID, which are safe to access. The downside is that if a task 268 * is temporarily overriding it's creds it will not be reflected here; 269 * however, it isn't clear that binder would handle that case well 270 * anyway. 271 * 272 * If this ever changes and we can safely reference the subjective 273 * creds/SID of another task, this function will make it easier to 274 * identify the various places where we make use of the task SIDs in 275 * the binder code. It is also likely that we will need to adjust 276 * the main drivers/android binder code as well. 277 */ 278 return task_sid_obj(task); 279 } 280 281 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 282 283 /* 284 * Try reloading inode security labels that have been marked as invalid. The 285 * @may_sleep parameter indicates when sleeping and thus reloading labels is 286 * allowed; when set to false, returns -ECHILD when the label is 287 * invalid. The @dentry parameter should be set to a dentry of the inode. 288 */ 289 static int __inode_security_revalidate(struct inode *inode, 290 struct dentry *dentry, 291 bool may_sleep) 292 { 293 struct inode_security_struct *isec = selinux_inode(inode); 294 295 might_sleep_if(may_sleep); 296 297 if (selinux_initialized(&selinux_state) && 298 isec->initialized != LABEL_INITIALIZED) { 299 if (!may_sleep) 300 return -ECHILD; 301 302 /* 303 * Try reloading the inode security label. This will fail if 304 * @opt_dentry is NULL and no dentry for this inode can be 305 * found; in that case, continue using the old label. 306 */ 307 inode_doinit_with_dentry(inode, dentry); 308 } 309 return 0; 310 } 311 312 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 313 { 314 return selinux_inode(inode); 315 } 316 317 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 318 { 319 int error; 320 321 error = __inode_security_revalidate(inode, NULL, !rcu); 322 if (error) 323 return ERR_PTR(error); 324 return selinux_inode(inode); 325 } 326 327 /* 328 * Get the security label of an inode. 329 */ 330 static struct inode_security_struct *inode_security(struct inode *inode) 331 { 332 __inode_security_revalidate(inode, NULL, true); 333 return selinux_inode(inode); 334 } 335 336 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 337 { 338 struct inode *inode = d_backing_inode(dentry); 339 340 return selinux_inode(inode); 341 } 342 343 /* 344 * Get the security label of a dentry's backing inode. 345 */ 346 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 347 { 348 struct inode *inode = d_backing_inode(dentry); 349 350 __inode_security_revalidate(inode, dentry, true); 351 return selinux_inode(inode); 352 } 353 354 static void inode_free_security(struct inode *inode) 355 { 356 struct inode_security_struct *isec = selinux_inode(inode); 357 struct superblock_security_struct *sbsec; 358 359 if (!isec) 360 return; 361 sbsec = selinux_superblock(inode->i_sb); 362 /* 363 * As not all inode security structures are in a list, we check for 364 * empty list outside of the lock to make sure that we won't waste 365 * time taking a lock doing nothing. 366 * 367 * The list_del_init() function can be safely called more than once. 368 * It should not be possible for this function to be called with 369 * concurrent list_add(), but for better safety against future changes 370 * in the code, we use list_empty_careful() here. 371 */ 372 if (!list_empty_careful(&isec->list)) { 373 spin_lock(&sbsec->isec_lock); 374 list_del_init(&isec->list); 375 spin_unlock(&sbsec->isec_lock); 376 } 377 } 378 379 struct selinux_mnt_opts { 380 const char *fscontext, *context, *rootcontext, *defcontext; 381 }; 382 383 static void selinux_free_mnt_opts(void *mnt_opts) 384 { 385 struct selinux_mnt_opts *opts = mnt_opts; 386 kfree(opts->fscontext); 387 kfree(opts->context); 388 kfree(opts->rootcontext); 389 kfree(opts->defcontext); 390 kfree(opts); 391 } 392 393 enum { 394 Opt_error = -1, 395 Opt_context = 0, 396 Opt_defcontext = 1, 397 Opt_fscontext = 2, 398 Opt_rootcontext = 3, 399 Opt_seclabel = 4, 400 }; 401 402 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 403 static struct { 404 const char *name; 405 int len; 406 int opt; 407 bool has_arg; 408 } tokens[] = { 409 A(context, true), 410 A(fscontext, true), 411 A(defcontext, true), 412 A(rootcontext, true), 413 A(seclabel, false), 414 }; 415 #undef A 416 417 static int match_opt_prefix(char *s, int l, char **arg) 418 { 419 int i; 420 421 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 422 size_t len = tokens[i].len; 423 if (len > l || memcmp(s, tokens[i].name, len)) 424 continue; 425 if (tokens[i].has_arg) { 426 if (len == l || s[len] != '=') 427 continue; 428 *arg = s + len + 1; 429 } else if (len != l) 430 continue; 431 return tokens[i].opt; 432 } 433 return Opt_error; 434 } 435 436 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 437 438 static int may_context_mount_sb_relabel(u32 sid, 439 struct superblock_security_struct *sbsec, 440 const struct cred *cred) 441 { 442 const struct task_security_struct *tsec = selinux_cred(cred); 443 int rc; 444 445 rc = avc_has_perm(&selinux_state, 446 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 447 FILESYSTEM__RELABELFROM, NULL); 448 if (rc) 449 return rc; 450 451 rc = avc_has_perm(&selinux_state, 452 tsec->sid, sid, SECCLASS_FILESYSTEM, 453 FILESYSTEM__RELABELTO, NULL); 454 return rc; 455 } 456 457 static int may_context_mount_inode_relabel(u32 sid, 458 struct superblock_security_struct *sbsec, 459 const struct cred *cred) 460 { 461 const struct task_security_struct *tsec = selinux_cred(cred); 462 int rc; 463 rc = avc_has_perm(&selinux_state, 464 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 465 FILESYSTEM__RELABELFROM, NULL); 466 if (rc) 467 return rc; 468 469 rc = avc_has_perm(&selinux_state, 470 sid, sbsec->sid, SECCLASS_FILESYSTEM, 471 FILESYSTEM__ASSOCIATE, NULL); 472 return rc; 473 } 474 475 static int selinux_is_genfs_special_handling(struct super_block *sb) 476 { 477 /* Special handling. Genfs but also in-core setxattr handler */ 478 return !strcmp(sb->s_type->name, "sysfs") || 479 !strcmp(sb->s_type->name, "pstore") || 480 !strcmp(sb->s_type->name, "debugfs") || 481 !strcmp(sb->s_type->name, "tracefs") || 482 !strcmp(sb->s_type->name, "rootfs") || 483 (selinux_policycap_cgroupseclabel() && 484 (!strcmp(sb->s_type->name, "cgroup") || 485 !strcmp(sb->s_type->name, "cgroup2"))); 486 } 487 488 static int selinux_is_sblabel_mnt(struct super_block *sb) 489 { 490 struct superblock_security_struct *sbsec = selinux_superblock(sb); 491 492 /* 493 * IMPORTANT: Double-check logic in this function when adding a new 494 * SECURITY_FS_USE_* definition! 495 */ 496 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 497 498 switch (sbsec->behavior) { 499 case SECURITY_FS_USE_XATTR: 500 case SECURITY_FS_USE_TRANS: 501 case SECURITY_FS_USE_TASK: 502 case SECURITY_FS_USE_NATIVE: 503 return 1; 504 505 case SECURITY_FS_USE_GENFS: 506 return selinux_is_genfs_special_handling(sb); 507 508 /* Never allow relabeling on context mounts */ 509 case SECURITY_FS_USE_MNTPOINT: 510 case SECURITY_FS_USE_NONE: 511 default: 512 return 0; 513 } 514 } 515 516 static int sb_check_xattr_support(struct super_block *sb) 517 { 518 struct superblock_security_struct *sbsec = sb->s_security; 519 struct dentry *root = sb->s_root; 520 struct inode *root_inode = d_backing_inode(root); 521 u32 sid; 522 int rc; 523 524 /* 525 * Make sure that the xattr handler exists and that no 526 * error other than -ENODATA is returned by getxattr on 527 * the root directory. -ENODATA is ok, as this may be 528 * the first boot of the SELinux kernel before we have 529 * assigned xattr values to the filesystem. 530 */ 531 if (!(root_inode->i_opflags & IOP_XATTR)) { 532 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", 533 sb->s_id, sb->s_type->name); 534 goto fallback; 535 } 536 537 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 538 if (rc < 0 && rc != -ENODATA) { 539 if (rc == -EOPNOTSUPP) { 540 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", 541 sb->s_id, sb->s_type->name); 542 goto fallback; 543 } else { 544 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", 545 sb->s_id, sb->s_type->name, -rc); 546 return rc; 547 } 548 } 549 return 0; 550 551 fallback: 552 /* No xattr support - try to fallback to genfs if possible. */ 553 rc = security_genfs_sid(&selinux_state, sb->s_type->name, "/", 554 SECCLASS_DIR, &sid); 555 if (rc) 556 return -EOPNOTSUPP; 557 558 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", 559 sb->s_id, sb->s_type->name); 560 sbsec->behavior = SECURITY_FS_USE_GENFS; 561 sbsec->sid = sid; 562 return 0; 563 } 564 565 static int sb_finish_set_opts(struct super_block *sb) 566 { 567 struct superblock_security_struct *sbsec = selinux_superblock(sb); 568 struct dentry *root = sb->s_root; 569 struct inode *root_inode = d_backing_inode(root); 570 int rc = 0; 571 572 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 573 rc = sb_check_xattr_support(sb); 574 if (rc) 575 return rc; 576 } 577 578 sbsec->flags |= SE_SBINITIALIZED; 579 580 /* 581 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 582 * leave the flag untouched because sb_clone_mnt_opts might be handing 583 * us a superblock that needs the flag to be cleared. 584 */ 585 if (selinux_is_sblabel_mnt(sb)) 586 sbsec->flags |= SBLABEL_MNT; 587 else 588 sbsec->flags &= ~SBLABEL_MNT; 589 590 /* Initialize the root inode. */ 591 rc = inode_doinit_with_dentry(root_inode, root); 592 593 /* Initialize any other inodes associated with the superblock, e.g. 594 inodes created prior to initial policy load or inodes created 595 during get_sb by a pseudo filesystem that directly 596 populates itself. */ 597 spin_lock(&sbsec->isec_lock); 598 while (!list_empty(&sbsec->isec_head)) { 599 struct inode_security_struct *isec = 600 list_first_entry(&sbsec->isec_head, 601 struct inode_security_struct, list); 602 struct inode *inode = isec->inode; 603 list_del_init(&isec->list); 604 spin_unlock(&sbsec->isec_lock); 605 inode = igrab(inode); 606 if (inode) { 607 if (!IS_PRIVATE(inode)) 608 inode_doinit_with_dentry(inode, NULL); 609 iput(inode); 610 } 611 spin_lock(&sbsec->isec_lock); 612 } 613 spin_unlock(&sbsec->isec_lock); 614 return rc; 615 } 616 617 static int bad_option(struct superblock_security_struct *sbsec, char flag, 618 u32 old_sid, u32 new_sid) 619 { 620 char mnt_flags = sbsec->flags & SE_MNTMASK; 621 622 /* check if the old mount command had the same options */ 623 if (sbsec->flags & SE_SBINITIALIZED) 624 if (!(sbsec->flags & flag) || 625 (old_sid != new_sid)) 626 return 1; 627 628 /* check if we were passed the same options twice, 629 * aka someone passed context=a,context=b 630 */ 631 if (!(sbsec->flags & SE_SBINITIALIZED)) 632 if (mnt_flags & flag) 633 return 1; 634 return 0; 635 } 636 637 static int parse_sid(struct super_block *sb, const char *s, u32 *sid) 638 { 639 int rc = security_context_str_to_sid(&selinux_state, s, 640 sid, GFP_KERNEL); 641 if (rc) 642 pr_warn("SELinux: security_context_str_to_sid" 643 "(%s) failed for (dev %s, type %s) errno=%d\n", 644 s, sb->s_id, sb->s_type->name, rc); 645 return rc; 646 } 647 648 /* 649 * Allow filesystems with binary mount data to explicitly set mount point 650 * labeling information. 651 */ 652 static int selinux_set_mnt_opts(struct super_block *sb, 653 void *mnt_opts, 654 unsigned long kern_flags, 655 unsigned long *set_kern_flags) 656 { 657 const struct cred *cred = current_cred(); 658 struct superblock_security_struct *sbsec = selinux_superblock(sb); 659 struct dentry *root = sb->s_root; 660 struct selinux_mnt_opts *opts = mnt_opts; 661 struct inode_security_struct *root_isec; 662 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 663 u32 defcontext_sid = 0; 664 int rc = 0; 665 666 mutex_lock(&sbsec->lock); 667 668 if (!selinux_initialized(&selinux_state)) { 669 if (!opts) { 670 /* Defer initialization until selinux_complete_init, 671 after the initial policy is loaded and the security 672 server is ready to handle calls. */ 673 goto out; 674 } 675 rc = -EINVAL; 676 pr_warn("SELinux: Unable to set superblock options " 677 "before the security server is initialized\n"); 678 goto out; 679 } 680 if (kern_flags && !set_kern_flags) { 681 /* Specifying internal flags without providing a place to 682 * place the results is not allowed */ 683 rc = -EINVAL; 684 goto out; 685 } 686 687 /* 688 * Binary mount data FS will come through this function twice. Once 689 * from an explicit call and once from the generic calls from the vfs. 690 * Since the generic VFS calls will not contain any security mount data 691 * we need to skip the double mount verification. 692 * 693 * This does open a hole in which we will not notice if the first 694 * mount using this sb set explict options and a second mount using 695 * this sb does not set any security options. (The first options 696 * will be used for both mounts) 697 */ 698 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 699 && !opts) 700 goto out; 701 702 root_isec = backing_inode_security_novalidate(root); 703 704 /* 705 * parse the mount options, check if they are valid sids. 706 * also check if someone is trying to mount the same sb more 707 * than once with different security options. 708 */ 709 if (opts) { 710 if (opts->fscontext) { 711 rc = parse_sid(sb, opts->fscontext, &fscontext_sid); 712 if (rc) 713 goto out; 714 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 715 fscontext_sid)) 716 goto out_double_mount; 717 sbsec->flags |= FSCONTEXT_MNT; 718 } 719 if (opts->context) { 720 rc = parse_sid(sb, opts->context, &context_sid); 721 if (rc) 722 goto out; 723 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 724 context_sid)) 725 goto out_double_mount; 726 sbsec->flags |= CONTEXT_MNT; 727 } 728 if (opts->rootcontext) { 729 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid); 730 if (rc) 731 goto out; 732 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 733 rootcontext_sid)) 734 goto out_double_mount; 735 sbsec->flags |= ROOTCONTEXT_MNT; 736 } 737 if (opts->defcontext) { 738 rc = parse_sid(sb, opts->defcontext, &defcontext_sid); 739 if (rc) 740 goto out; 741 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 742 defcontext_sid)) 743 goto out_double_mount; 744 sbsec->flags |= DEFCONTEXT_MNT; 745 } 746 } 747 748 if (sbsec->flags & SE_SBINITIALIZED) { 749 /* previously mounted with options, but not on this attempt? */ 750 if ((sbsec->flags & SE_MNTMASK) && !opts) 751 goto out_double_mount; 752 rc = 0; 753 goto out; 754 } 755 756 if (strcmp(sb->s_type->name, "proc") == 0) 757 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 758 759 if (!strcmp(sb->s_type->name, "debugfs") || 760 !strcmp(sb->s_type->name, "tracefs") || 761 !strcmp(sb->s_type->name, "binder") || 762 !strcmp(sb->s_type->name, "bpf") || 763 !strcmp(sb->s_type->name, "pstore")) 764 sbsec->flags |= SE_SBGENFS; 765 766 if (!strcmp(sb->s_type->name, "sysfs") || 767 !strcmp(sb->s_type->name, "cgroup") || 768 !strcmp(sb->s_type->name, "cgroup2")) 769 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 770 771 if (!sbsec->behavior) { 772 /* 773 * Determine the labeling behavior to use for this 774 * filesystem type. 775 */ 776 rc = security_fs_use(&selinux_state, sb); 777 if (rc) { 778 pr_warn("%s: security_fs_use(%s) returned %d\n", 779 __func__, sb->s_type->name, rc); 780 goto out; 781 } 782 } 783 784 /* 785 * If this is a user namespace mount and the filesystem type is not 786 * explicitly whitelisted, then no contexts are allowed on the command 787 * line and security labels must be ignored. 788 */ 789 if (sb->s_user_ns != &init_user_ns && 790 strcmp(sb->s_type->name, "tmpfs") && 791 strcmp(sb->s_type->name, "ramfs") && 792 strcmp(sb->s_type->name, "devpts") && 793 strcmp(sb->s_type->name, "overlay")) { 794 if (context_sid || fscontext_sid || rootcontext_sid || 795 defcontext_sid) { 796 rc = -EACCES; 797 goto out; 798 } 799 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 800 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 801 rc = security_transition_sid(&selinux_state, 802 current_sid(), 803 current_sid(), 804 SECCLASS_FILE, NULL, 805 &sbsec->mntpoint_sid); 806 if (rc) 807 goto out; 808 } 809 goto out_set_opts; 810 } 811 812 /* sets the context of the superblock for the fs being mounted. */ 813 if (fscontext_sid) { 814 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 815 if (rc) 816 goto out; 817 818 sbsec->sid = fscontext_sid; 819 } 820 821 /* 822 * Switch to using mount point labeling behavior. 823 * sets the label used on all file below the mountpoint, and will set 824 * the superblock context if not already set. 825 */ 826 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 827 sbsec->behavior = SECURITY_FS_USE_NATIVE; 828 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 829 } 830 831 if (context_sid) { 832 if (!fscontext_sid) { 833 rc = may_context_mount_sb_relabel(context_sid, sbsec, 834 cred); 835 if (rc) 836 goto out; 837 sbsec->sid = context_sid; 838 } else { 839 rc = may_context_mount_inode_relabel(context_sid, sbsec, 840 cred); 841 if (rc) 842 goto out; 843 } 844 if (!rootcontext_sid) 845 rootcontext_sid = context_sid; 846 847 sbsec->mntpoint_sid = context_sid; 848 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 849 } 850 851 if (rootcontext_sid) { 852 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 853 cred); 854 if (rc) 855 goto out; 856 857 root_isec->sid = rootcontext_sid; 858 root_isec->initialized = LABEL_INITIALIZED; 859 } 860 861 if (defcontext_sid) { 862 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 863 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 864 rc = -EINVAL; 865 pr_warn("SELinux: defcontext option is " 866 "invalid for this filesystem type\n"); 867 goto out; 868 } 869 870 if (defcontext_sid != sbsec->def_sid) { 871 rc = may_context_mount_inode_relabel(defcontext_sid, 872 sbsec, cred); 873 if (rc) 874 goto out; 875 } 876 877 sbsec->def_sid = defcontext_sid; 878 } 879 880 out_set_opts: 881 rc = sb_finish_set_opts(sb); 882 out: 883 mutex_unlock(&sbsec->lock); 884 return rc; 885 out_double_mount: 886 rc = -EINVAL; 887 pr_warn("SELinux: mount invalid. Same superblock, different " 888 "security settings for (dev %s, type %s)\n", sb->s_id, 889 sb->s_type->name); 890 goto out; 891 } 892 893 static int selinux_cmp_sb_context(const struct super_block *oldsb, 894 const struct super_block *newsb) 895 { 896 struct superblock_security_struct *old = selinux_superblock(oldsb); 897 struct superblock_security_struct *new = selinux_superblock(newsb); 898 char oldflags = old->flags & SE_MNTMASK; 899 char newflags = new->flags & SE_MNTMASK; 900 901 if (oldflags != newflags) 902 goto mismatch; 903 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 904 goto mismatch; 905 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 906 goto mismatch; 907 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 908 goto mismatch; 909 if (oldflags & ROOTCONTEXT_MNT) { 910 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 911 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 912 if (oldroot->sid != newroot->sid) 913 goto mismatch; 914 } 915 return 0; 916 mismatch: 917 pr_warn("SELinux: mount invalid. Same superblock, " 918 "different security settings for (dev %s, " 919 "type %s)\n", newsb->s_id, newsb->s_type->name); 920 return -EBUSY; 921 } 922 923 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 924 struct super_block *newsb, 925 unsigned long kern_flags, 926 unsigned long *set_kern_flags) 927 { 928 int rc = 0; 929 const struct superblock_security_struct *oldsbsec = 930 selinux_superblock(oldsb); 931 struct superblock_security_struct *newsbsec = selinux_superblock(newsb); 932 933 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 934 int set_context = (oldsbsec->flags & CONTEXT_MNT); 935 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 936 937 /* 938 * if the parent was able to be mounted it clearly had no special lsm 939 * mount options. thus we can safely deal with this superblock later 940 */ 941 if (!selinux_initialized(&selinux_state)) 942 return 0; 943 944 /* 945 * Specifying internal flags without providing a place to 946 * place the results is not allowed. 947 */ 948 if (kern_flags && !set_kern_flags) 949 return -EINVAL; 950 951 /* how can we clone if the old one wasn't set up?? */ 952 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 953 954 /* if fs is reusing a sb, make sure that the contexts match */ 955 if (newsbsec->flags & SE_SBINITIALIZED) { 956 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 957 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 958 return selinux_cmp_sb_context(oldsb, newsb); 959 } 960 961 mutex_lock(&newsbsec->lock); 962 963 newsbsec->flags = oldsbsec->flags; 964 965 newsbsec->sid = oldsbsec->sid; 966 newsbsec->def_sid = oldsbsec->def_sid; 967 newsbsec->behavior = oldsbsec->behavior; 968 969 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 970 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 971 rc = security_fs_use(&selinux_state, newsb); 972 if (rc) 973 goto out; 974 } 975 976 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 977 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 978 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 979 } 980 981 if (set_context) { 982 u32 sid = oldsbsec->mntpoint_sid; 983 984 if (!set_fscontext) 985 newsbsec->sid = sid; 986 if (!set_rootcontext) { 987 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 988 newisec->sid = sid; 989 } 990 newsbsec->mntpoint_sid = sid; 991 } 992 if (set_rootcontext) { 993 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 994 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 995 996 newisec->sid = oldisec->sid; 997 } 998 999 sb_finish_set_opts(newsb); 1000 out: 1001 mutex_unlock(&newsbsec->lock); 1002 return rc; 1003 } 1004 1005 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 1006 { 1007 struct selinux_mnt_opts *opts = *mnt_opts; 1008 1009 if (token == Opt_seclabel) /* eaten and completely ignored */ 1010 return 0; 1011 1012 if (!opts) { 1013 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 1014 if (!opts) 1015 return -ENOMEM; 1016 *mnt_opts = opts; 1017 } 1018 if (!s) 1019 return -ENOMEM; 1020 switch (token) { 1021 case Opt_context: 1022 if (opts->context || opts->defcontext) 1023 goto Einval; 1024 opts->context = s; 1025 break; 1026 case Opt_fscontext: 1027 if (opts->fscontext) 1028 goto Einval; 1029 opts->fscontext = s; 1030 break; 1031 case Opt_rootcontext: 1032 if (opts->rootcontext) 1033 goto Einval; 1034 opts->rootcontext = s; 1035 break; 1036 case Opt_defcontext: 1037 if (opts->context || opts->defcontext) 1038 goto Einval; 1039 opts->defcontext = s; 1040 break; 1041 } 1042 return 0; 1043 Einval: 1044 pr_warn(SEL_MOUNT_FAIL_MSG); 1045 return -EINVAL; 1046 } 1047 1048 static int selinux_add_mnt_opt(const char *option, const char *val, int len, 1049 void **mnt_opts) 1050 { 1051 int token = Opt_error; 1052 int rc, i; 1053 1054 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 1055 if (strcmp(option, tokens[i].name) == 0) { 1056 token = tokens[i].opt; 1057 break; 1058 } 1059 } 1060 1061 if (token == Opt_error) 1062 return -EINVAL; 1063 1064 if (token != Opt_seclabel) { 1065 val = kmemdup_nul(val, len, GFP_KERNEL); 1066 if (!val) { 1067 rc = -ENOMEM; 1068 goto free_opt; 1069 } 1070 } 1071 rc = selinux_add_opt(token, val, mnt_opts); 1072 if (unlikely(rc)) { 1073 kfree(val); 1074 goto free_opt; 1075 } 1076 return rc; 1077 1078 free_opt: 1079 if (*mnt_opts) { 1080 selinux_free_mnt_opts(*mnt_opts); 1081 *mnt_opts = NULL; 1082 } 1083 return rc; 1084 } 1085 1086 static int show_sid(struct seq_file *m, u32 sid) 1087 { 1088 char *context = NULL; 1089 u32 len; 1090 int rc; 1091 1092 rc = security_sid_to_context(&selinux_state, sid, 1093 &context, &len); 1094 if (!rc) { 1095 bool has_comma = context && strchr(context, ','); 1096 1097 seq_putc(m, '='); 1098 if (has_comma) 1099 seq_putc(m, '\"'); 1100 seq_escape(m, context, "\"\n\\"); 1101 if (has_comma) 1102 seq_putc(m, '\"'); 1103 } 1104 kfree(context); 1105 return rc; 1106 } 1107 1108 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1109 { 1110 struct superblock_security_struct *sbsec = selinux_superblock(sb); 1111 int rc; 1112 1113 if (!(sbsec->flags & SE_SBINITIALIZED)) 1114 return 0; 1115 1116 if (!selinux_initialized(&selinux_state)) 1117 return 0; 1118 1119 if (sbsec->flags & FSCONTEXT_MNT) { 1120 seq_putc(m, ','); 1121 seq_puts(m, FSCONTEXT_STR); 1122 rc = show_sid(m, sbsec->sid); 1123 if (rc) 1124 return rc; 1125 } 1126 if (sbsec->flags & CONTEXT_MNT) { 1127 seq_putc(m, ','); 1128 seq_puts(m, CONTEXT_STR); 1129 rc = show_sid(m, sbsec->mntpoint_sid); 1130 if (rc) 1131 return rc; 1132 } 1133 if (sbsec->flags & DEFCONTEXT_MNT) { 1134 seq_putc(m, ','); 1135 seq_puts(m, DEFCONTEXT_STR); 1136 rc = show_sid(m, sbsec->def_sid); 1137 if (rc) 1138 return rc; 1139 } 1140 if (sbsec->flags & ROOTCONTEXT_MNT) { 1141 struct dentry *root = sb->s_root; 1142 struct inode_security_struct *isec = backing_inode_security(root); 1143 seq_putc(m, ','); 1144 seq_puts(m, ROOTCONTEXT_STR); 1145 rc = show_sid(m, isec->sid); 1146 if (rc) 1147 return rc; 1148 } 1149 if (sbsec->flags & SBLABEL_MNT) { 1150 seq_putc(m, ','); 1151 seq_puts(m, SECLABEL_STR); 1152 } 1153 return 0; 1154 } 1155 1156 static inline u16 inode_mode_to_security_class(umode_t mode) 1157 { 1158 switch (mode & S_IFMT) { 1159 case S_IFSOCK: 1160 return SECCLASS_SOCK_FILE; 1161 case S_IFLNK: 1162 return SECCLASS_LNK_FILE; 1163 case S_IFREG: 1164 return SECCLASS_FILE; 1165 case S_IFBLK: 1166 return SECCLASS_BLK_FILE; 1167 case S_IFDIR: 1168 return SECCLASS_DIR; 1169 case S_IFCHR: 1170 return SECCLASS_CHR_FILE; 1171 case S_IFIFO: 1172 return SECCLASS_FIFO_FILE; 1173 1174 } 1175 1176 return SECCLASS_FILE; 1177 } 1178 1179 static inline int default_protocol_stream(int protocol) 1180 { 1181 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || 1182 protocol == IPPROTO_MPTCP); 1183 } 1184 1185 static inline int default_protocol_dgram(int protocol) 1186 { 1187 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1188 } 1189 1190 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1191 { 1192 int extsockclass = selinux_policycap_extsockclass(); 1193 1194 switch (family) { 1195 case PF_UNIX: 1196 switch (type) { 1197 case SOCK_STREAM: 1198 case SOCK_SEQPACKET: 1199 return SECCLASS_UNIX_STREAM_SOCKET; 1200 case SOCK_DGRAM: 1201 case SOCK_RAW: 1202 return SECCLASS_UNIX_DGRAM_SOCKET; 1203 } 1204 break; 1205 case PF_INET: 1206 case PF_INET6: 1207 switch (type) { 1208 case SOCK_STREAM: 1209 case SOCK_SEQPACKET: 1210 if (default_protocol_stream(protocol)) 1211 return SECCLASS_TCP_SOCKET; 1212 else if (extsockclass && protocol == IPPROTO_SCTP) 1213 return SECCLASS_SCTP_SOCKET; 1214 else 1215 return SECCLASS_RAWIP_SOCKET; 1216 case SOCK_DGRAM: 1217 if (default_protocol_dgram(protocol)) 1218 return SECCLASS_UDP_SOCKET; 1219 else if (extsockclass && (protocol == IPPROTO_ICMP || 1220 protocol == IPPROTO_ICMPV6)) 1221 return SECCLASS_ICMP_SOCKET; 1222 else 1223 return SECCLASS_RAWIP_SOCKET; 1224 case SOCK_DCCP: 1225 return SECCLASS_DCCP_SOCKET; 1226 default: 1227 return SECCLASS_RAWIP_SOCKET; 1228 } 1229 break; 1230 case PF_NETLINK: 1231 switch (protocol) { 1232 case NETLINK_ROUTE: 1233 return SECCLASS_NETLINK_ROUTE_SOCKET; 1234 case NETLINK_SOCK_DIAG: 1235 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1236 case NETLINK_NFLOG: 1237 return SECCLASS_NETLINK_NFLOG_SOCKET; 1238 case NETLINK_XFRM: 1239 return SECCLASS_NETLINK_XFRM_SOCKET; 1240 case NETLINK_SELINUX: 1241 return SECCLASS_NETLINK_SELINUX_SOCKET; 1242 case NETLINK_ISCSI: 1243 return SECCLASS_NETLINK_ISCSI_SOCKET; 1244 case NETLINK_AUDIT: 1245 return SECCLASS_NETLINK_AUDIT_SOCKET; 1246 case NETLINK_FIB_LOOKUP: 1247 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1248 case NETLINK_CONNECTOR: 1249 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1250 case NETLINK_NETFILTER: 1251 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1252 case NETLINK_DNRTMSG: 1253 return SECCLASS_NETLINK_DNRT_SOCKET; 1254 case NETLINK_KOBJECT_UEVENT: 1255 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1256 case NETLINK_GENERIC: 1257 return SECCLASS_NETLINK_GENERIC_SOCKET; 1258 case NETLINK_SCSITRANSPORT: 1259 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1260 case NETLINK_RDMA: 1261 return SECCLASS_NETLINK_RDMA_SOCKET; 1262 case NETLINK_CRYPTO: 1263 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1264 default: 1265 return SECCLASS_NETLINK_SOCKET; 1266 } 1267 case PF_PACKET: 1268 return SECCLASS_PACKET_SOCKET; 1269 case PF_KEY: 1270 return SECCLASS_KEY_SOCKET; 1271 case PF_APPLETALK: 1272 return SECCLASS_APPLETALK_SOCKET; 1273 } 1274 1275 if (extsockclass) { 1276 switch (family) { 1277 case PF_AX25: 1278 return SECCLASS_AX25_SOCKET; 1279 case PF_IPX: 1280 return SECCLASS_IPX_SOCKET; 1281 case PF_NETROM: 1282 return SECCLASS_NETROM_SOCKET; 1283 case PF_ATMPVC: 1284 return SECCLASS_ATMPVC_SOCKET; 1285 case PF_X25: 1286 return SECCLASS_X25_SOCKET; 1287 case PF_ROSE: 1288 return SECCLASS_ROSE_SOCKET; 1289 case PF_DECnet: 1290 return SECCLASS_DECNET_SOCKET; 1291 case PF_ATMSVC: 1292 return SECCLASS_ATMSVC_SOCKET; 1293 case PF_RDS: 1294 return SECCLASS_RDS_SOCKET; 1295 case PF_IRDA: 1296 return SECCLASS_IRDA_SOCKET; 1297 case PF_PPPOX: 1298 return SECCLASS_PPPOX_SOCKET; 1299 case PF_LLC: 1300 return SECCLASS_LLC_SOCKET; 1301 case PF_CAN: 1302 return SECCLASS_CAN_SOCKET; 1303 case PF_TIPC: 1304 return SECCLASS_TIPC_SOCKET; 1305 case PF_BLUETOOTH: 1306 return SECCLASS_BLUETOOTH_SOCKET; 1307 case PF_IUCV: 1308 return SECCLASS_IUCV_SOCKET; 1309 case PF_RXRPC: 1310 return SECCLASS_RXRPC_SOCKET; 1311 case PF_ISDN: 1312 return SECCLASS_ISDN_SOCKET; 1313 case PF_PHONET: 1314 return SECCLASS_PHONET_SOCKET; 1315 case PF_IEEE802154: 1316 return SECCLASS_IEEE802154_SOCKET; 1317 case PF_CAIF: 1318 return SECCLASS_CAIF_SOCKET; 1319 case PF_ALG: 1320 return SECCLASS_ALG_SOCKET; 1321 case PF_NFC: 1322 return SECCLASS_NFC_SOCKET; 1323 case PF_VSOCK: 1324 return SECCLASS_VSOCK_SOCKET; 1325 case PF_KCM: 1326 return SECCLASS_KCM_SOCKET; 1327 case PF_QIPCRTR: 1328 return SECCLASS_QIPCRTR_SOCKET; 1329 case PF_SMC: 1330 return SECCLASS_SMC_SOCKET; 1331 case PF_XDP: 1332 return SECCLASS_XDP_SOCKET; 1333 #if PF_MAX > 45 1334 #error New address family defined, please update this function. 1335 #endif 1336 } 1337 } 1338 1339 return SECCLASS_SOCKET; 1340 } 1341 1342 static int selinux_genfs_get_sid(struct dentry *dentry, 1343 u16 tclass, 1344 u16 flags, 1345 u32 *sid) 1346 { 1347 int rc; 1348 struct super_block *sb = dentry->d_sb; 1349 char *buffer, *path; 1350 1351 buffer = (char *)__get_free_page(GFP_KERNEL); 1352 if (!buffer) 1353 return -ENOMEM; 1354 1355 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1356 if (IS_ERR(path)) 1357 rc = PTR_ERR(path); 1358 else { 1359 if (flags & SE_SBPROC) { 1360 /* each process gets a /proc/PID/ entry. Strip off the 1361 * PID part to get a valid selinux labeling. 1362 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1363 while (path[1] >= '0' && path[1] <= '9') { 1364 path[1] = '/'; 1365 path++; 1366 } 1367 } 1368 rc = security_genfs_sid(&selinux_state, sb->s_type->name, 1369 path, tclass, sid); 1370 if (rc == -ENOENT) { 1371 /* No match in policy, mark as unlabeled. */ 1372 *sid = SECINITSID_UNLABELED; 1373 rc = 0; 1374 } 1375 } 1376 free_page((unsigned long)buffer); 1377 return rc; 1378 } 1379 1380 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1381 u32 def_sid, u32 *sid) 1382 { 1383 #define INITCONTEXTLEN 255 1384 char *context; 1385 unsigned int len; 1386 int rc; 1387 1388 len = INITCONTEXTLEN; 1389 context = kmalloc(len + 1, GFP_NOFS); 1390 if (!context) 1391 return -ENOMEM; 1392 1393 context[len] = '\0'; 1394 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1395 if (rc == -ERANGE) { 1396 kfree(context); 1397 1398 /* Need a larger buffer. Query for the right size. */ 1399 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1400 if (rc < 0) 1401 return rc; 1402 1403 len = rc; 1404 context = kmalloc(len + 1, GFP_NOFS); 1405 if (!context) 1406 return -ENOMEM; 1407 1408 context[len] = '\0'; 1409 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1410 context, len); 1411 } 1412 if (rc < 0) { 1413 kfree(context); 1414 if (rc != -ENODATA) { 1415 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1416 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1417 return rc; 1418 } 1419 *sid = def_sid; 1420 return 0; 1421 } 1422 1423 rc = security_context_to_sid_default(&selinux_state, context, rc, sid, 1424 def_sid, GFP_NOFS); 1425 if (rc) { 1426 char *dev = inode->i_sb->s_id; 1427 unsigned long ino = inode->i_ino; 1428 1429 if (rc == -EINVAL) { 1430 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", 1431 ino, dev, context); 1432 } else { 1433 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1434 __func__, context, -rc, dev, ino); 1435 } 1436 } 1437 kfree(context); 1438 return 0; 1439 } 1440 1441 /* The inode's security attributes must be initialized before first use. */ 1442 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1443 { 1444 struct superblock_security_struct *sbsec = NULL; 1445 struct inode_security_struct *isec = selinux_inode(inode); 1446 u32 task_sid, sid = 0; 1447 u16 sclass; 1448 struct dentry *dentry; 1449 int rc = 0; 1450 1451 if (isec->initialized == LABEL_INITIALIZED) 1452 return 0; 1453 1454 spin_lock(&isec->lock); 1455 if (isec->initialized == LABEL_INITIALIZED) 1456 goto out_unlock; 1457 1458 if (isec->sclass == SECCLASS_FILE) 1459 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1460 1461 sbsec = selinux_superblock(inode->i_sb); 1462 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1463 /* Defer initialization until selinux_complete_init, 1464 after the initial policy is loaded and the security 1465 server is ready to handle calls. */ 1466 spin_lock(&sbsec->isec_lock); 1467 if (list_empty(&isec->list)) 1468 list_add(&isec->list, &sbsec->isec_head); 1469 spin_unlock(&sbsec->isec_lock); 1470 goto out_unlock; 1471 } 1472 1473 sclass = isec->sclass; 1474 task_sid = isec->task_sid; 1475 sid = isec->sid; 1476 isec->initialized = LABEL_PENDING; 1477 spin_unlock(&isec->lock); 1478 1479 switch (sbsec->behavior) { 1480 case SECURITY_FS_USE_NATIVE: 1481 break; 1482 case SECURITY_FS_USE_XATTR: 1483 if (!(inode->i_opflags & IOP_XATTR)) { 1484 sid = sbsec->def_sid; 1485 break; 1486 } 1487 /* Need a dentry, since the xattr API requires one. 1488 Life would be simpler if we could just pass the inode. */ 1489 if (opt_dentry) { 1490 /* Called from d_instantiate or d_splice_alias. */ 1491 dentry = dget(opt_dentry); 1492 } else { 1493 /* 1494 * Called from selinux_complete_init, try to find a dentry. 1495 * Some filesystems really want a connected one, so try 1496 * that first. We could split SECURITY_FS_USE_XATTR in 1497 * two, depending upon that... 1498 */ 1499 dentry = d_find_alias(inode); 1500 if (!dentry) 1501 dentry = d_find_any_alias(inode); 1502 } 1503 if (!dentry) { 1504 /* 1505 * this is can be hit on boot when a file is accessed 1506 * before the policy is loaded. When we load policy we 1507 * may find inodes that have no dentry on the 1508 * sbsec->isec_head list. No reason to complain as these 1509 * will get fixed up the next time we go through 1510 * inode_doinit with a dentry, before these inodes could 1511 * be used again by userspace. 1512 */ 1513 goto out_invalid; 1514 } 1515 1516 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1517 &sid); 1518 dput(dentry); 1519 if (rc) 1520 goto out; 1521 break; 1522 case SECURITY_FS_USE_TASK: 1523 sid = task_sid; 1524 break; 1525 case SECURITY_FS_USE_TRANS: 1526 /* Default to the fs SID. */ 1527 sid = sbsec->sid; 1528 1529 /* Try to obtain a transition SID. */ 1530 rc = security_transition_sid(&selinux_state, task_sid, sid, 1531 sclass, NULL, &sid); 1532 if (rc) 1533 goto out; 1534 break; 1535 case SECURITY_FS_USE_MNTPOINT: 1536 sid = sbsec->mntpoint_sid; 1537 break; 1538 default: 1539 /* Default to the fs superblock SID. */ 1540 sid = sbsec->sid; 1541 1542 if ((sbsec->flags & SE_SBGENFS) && 1543 (!S_ISLNK(inode->i_mode) || 1544 selinux_policycap_genfs_seclabel_symlinks())) { 1545 /* We must have a dentry to determine the label on 1546 * procfs inodes */ 1547 if (opt_dentry) { 1548 /* Called from d_instantiate or 1549 * d_splice_alias. */ 1550 dentry = dget(opt_dentry); 1551 } else { 1552 /* Called from selinux_complete_init, try to 1553 * find a dentry. Some filesystems really want 1554 * a connected one, so try that first. 1555 */ 1556 dentry = d_find_alias(inode); 1557 if (!dentry) 1558 dentry = d_find_any_alias(inode); 1559 } 1560 /* 1561 * This can be hit on boot when a file is accessed 1562 * before the policy is loaded. When we load policy we 1563 * may find inodes that have no dentry on the 1564 * sbsec->isec_head list. No reason to complain as 1565 * these will get fixed up the next time we go through 1566 * inode_doinit() with a dentry, before these inodes 1567 * could be used again by userspace. 1568 */ 1569 if (!dentry) 1570 goto out_invalid; 1571 rc = selinux_genfs_get_sid(dentry, sclass, 1572 sbsec->flags, &sid); 1573 if (rc) { 1574 dput(dentry); 1575 goto out; 1576 } 1577 1578 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1579 (inode->i_opflags & IOP_XATTR)) { 1580 rc = inode_doinit_use_xattr(inode, dentry, 1581 sid, &sid); 1582 if (rc) { 1583 dput(dentry); 1584 goto out; 1585 } 1586 } 1587 dput(dentry); 1588 } 1589 break; 1590 } 1591 1592 out: 1593 spin_lock(&isec->lock); 1594 if (isec->initialized == LABEL_PENDING) { 1595 if (rc) { 1596 isec->initialized = LABEL_INVALID; 1597 goto out_unlock; 1598 } 1599 isec->initialized = LABEL_INITIALIZED; 1600 isec->sid = sid; 1601 } 1602 1603 out_unlock: 1604 spin_unlock(&isec->lock); 1605 return rc; 1606 1607 out_invalid: 1608 spin_lock(&isec->lock); 1609 if (isec->initialized == LABEL_PENDING) { 1610 isec->initialized = LABEL_INVALID; 1611 isec->sid = sid; 1612 } 1613 spin_unlock(&isec->lock); 1614 return 0; 1615 } 1616 1617 /* Convert a Linux signal to an access vector. */ 1618 static inline u32 signal_to_av(int sig) 1619 { 1620 u32 perm = 0; 1621 1622 switch (sig) { 1623 case SIGCHLD: 1624 /* Commonly granted from child to parent. */ 1625 perm = PROCESS__SIGCHLD; 1626 break; 1627 case SIGKILL: 1628 /* Cannot be caught or ignored */ 1629 perm = PROCESS__SIGKILL; 1630 break; 1631 case SIGSTOP: 1632 /* Cannot be caught or ignored */ 1633 perm = PROCESS__SIGSTOP; 1634 break; 1635 default: 1636 /* All other signals. */ 1637 perm = PROCESS__SIGNAL; 1638 break; 1639 } 1640 1641 return perm; 1642 } 1643 1644 #if CAP_LAST_CAP > 63 1645 #error Fix SELinux to handle capabilities > 63. 1646 #endif 1647 1648 /* Check whether a task is allowed to use a capability. */ 1649 static int cred_has_capability(const struct cred *cred, 1650 int cap, unsigned int opts, bool initns) 1651 { 1652 struct common_audit_data ad; 1653 struct av_decision avd; 1654 u16 sclass; 1655 u32 sid = cred_sid(cred); 1656 u32 av = CAP_TO_MASK(cap); 1657 int rc; 1658 1659 ad.type = LSM_AUDIT_DATA_CAP; 1660 ad.u.cap = cap; 1661 1662 switch (CAP_TO_INDEX(cap)) { 1663 case 0: 1664 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1665 break; 1666 case 1: 1667 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1668 break; 1669 default: 1670 pr_err("SELinux: out of range capability %d\n", cap); 1671 BUG(); 1672 return -EINVAL; 1673 } 1674 1675 rc = avc_has_perm_noaudit(&selinux_state, 1676 sid, sid, sclass, av, 0, &avd); 1677 if (!(opts & CAP_OPT_NOAUDIT)) { 1678 int rc2 = avc_audit(&selinux_state, 1679 sid, sid, sclass, av, &avd, rc, &ad, 0); 1680 if (rc2) 1681 return rc2; 1682 } 1683 return rc; 1684 } 1685 1686 /* Check whether a task has a particular permission to an inode. 1687 The 'adp' parameter is optional and allows other audit 1688 data to be passed (e.g. the dentry). */ 1689 static int inode_has_perm(const struct cred *cred, 1690 struct inode *inode, 1691 u32 perms, 1692 struct common_audit_data *adp) 1693 { 1694 struct inode_security_struct *isec; 1695 u32 sid; 1696 1697 validate_creds(cred); 1698 1699 if (unlikely(IS_PRIVATE(inode))) 1700 return 0; 1701 1702 sid = cred_sid(cred); 1703 isec = selinux_inode(inode); 1704 1705 return avc_has_perm(&selinux_state, 1706 sid, isec->sid, isec->sclass, perms, adp); 1707 } 1708 1709 /* Same as inode_has_perm, but pass explicit audit data containing 1710 the dentry to help the auditing code to more easily generate the 1711 pathname if needed. */ 1712 static inline int dentry_has_perm(const struct cred *cred, 1713 struct dentry *dentry, 1714 u32 av) 1715 { 1716 struct inode *inode = d_backing_inode(dentry); 1717 struct common_audit_data ad; 1718 1719 ad.type = LSM_AUDIT_DATA_DENTRY; 1720 ad.u.dentry = dentry; 1721 __inode_security_revalidate(inode, dentry, true); 1722 return inode_has_perm(cred, inode, av, &ad); 1723 } 1724 1725 /* Same as inode_has_perm, but pass explicit audit data containing 1726 the path to help the auditing code to more easily generate the 1727 pathname if needed. */ 1728 static inline int path_has_perm(const struct cred *cred, 1729 const struct path *path, 1730 u32 av) 1731 { 1732 struct inode *inode = d_backing_inode(path->dentry); 1733 struct common_audit_data ad; 1734 1735 ad.type = LSM_AUDIT_DATA_PATH; 1736 ad.u.path = *path; 1737 __inode_security_revalidate(inode, path->dentry, true); 1738 return inode_has_perm(cred, inode, av, &ad); 1739 } 1740 1741 /* Same as path_has_perm, but uses the inode from the file struct. */ 1742 static inline int file_path_has_perm(const struct cred *cred, 1743 struct file *file, 1744 u32 av) 1745 { 1746 struct common_audit_data ad; 1747 1748 ad.type = LSM_AUDIT_DATA_FILE; 1749 ad.u.file = file; 1750 return inode_has_perm(cred, file_inode(file), av, &ad); 1751 } 1752 1753 #ifdef CONFIG_BPF_SYSCALL 1754 static int bpf_fd_pass(struct file *file, u32 sid); 1755 #endif 1756 1757 /* Check whether a task can use an open file descriptor to 1758 access an inode in a given way. Check access to the 1759 descriptor itself, and then use dentry_has_perm to 1760 check a particular permission to the file. 1761 Access to the descriptor is implicitly granted if it 1762 has the same SID as the process. If av is zero, then 1763 access to the file is not checked, e.g. for cases 1764 where only the descriptor is affected like seek. */ 1765 static int file_has_perm(const struct cred *cred, 1766 struct file *file, 1767 u32 av) 1768 { 1769 struct file_security_struct *fsec = selinux_file(file); 1770 struct inode *inode = file_inode(file); 1771 struct common_audit_data ad; 1772 u32 sid = cred_sid(cred); 1773 int rc; 1774 1775 ad.type = LSM_AUDIT_DATA_FILE; 1776 ad.u.file = file; 1777 1778 if (sid != fsec->sid) { 1779 rc = avc_has_perm(&selinux_state, 1780 sid, fsec->sid, 1781 SECCLASS_FD, 1782 FD__USE, 1783 &ad); 1784 if (rc) 1785 goto out; 1786 } 1787 1788 #ifdef CONFIG_BPF_SYSCALL 1789 rc = bpf_fd_pass(file, cred_sid(cred)); 1790 if (rc) 1791 return rc; 1792 #endif 1793 1794 /* av is zero if only checking access to the descriptor. */ 1795 rc = 0; 1796 if (av) 1797 rc = inode_has_perm(cred, inode, av, &ad); 1798 1799 out: 1800 return rc; 1801 } 1802 1803 /* 1804 * Determine the label for an inode that might be unioned. 1805 */ 1806 static int 1807 selinux_determine_inode_label(const struct task_security_struct *tsec, 1808 struct inode *dir, 1809 const struct qstr *name, u16 tclass, 1810 u32 *_new_isid) 1811 { 1812 const struct superblock_security_struct *sbsec = 1813 selinux_superblock(dir->i_sb); 1814 1815 if ((sbsec->flags & SE_SBINITIALIZED) && 1816 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1817 *_new_isid = sbsec->mntpoint_sid; 1818 } else if ((sbsec->flags & SBLABEL_MNT) && 1819 tsec->create_sid) { 1820 *_new_isid = tsec->create_sid; 1821 } else { 1822 const struct inode_security_struct *dsec = inode_security(dir); 1823 return security_transition_sid(&selinux_state, tsec->sid, 1824 dsec->sid, tclass, 1825 name, _new_isid); 1826 } 1827 1828 return 0; 1829 } 1830 1831 /* Check whether a task can create a file. */ 1832 static int may_create(struct inode *dir, 1833 struct dentry *dentry, 1834 u16 tclass) 1835 { 1836 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1837 struct inode_security_struct *dsec; 1838 struct superblock_security_struct *sbsec; 1839 u32 sid, newsid; 1840 struct common_audit_data ad; 1841 int rc; 1842 1843 dsec = inode_security(dir); 1844 sbsec = selinux_superblock(dir->i_sb); 1845 1846 sid = tsec->sid; 1847 1848 ad.type = LSM_AUDIT_DATA_DENTRY; 1849 ad.u.dentry = dentry; 1850 1851 rc = avc_has_perm(&selinux_state, 1852 sid, dsec->sid, SECCLASS_DIR, 1853 DIR__ADD_NAME | DIR__SEARCH, 1854 &ad); 1855 if (rc) 1856 return rc; 1857 1858 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1859 &newsid); 1860 if (rc) 1861 return rc; 1862 1863 rc = avc_has_perm(&selinux_state, 1864 sid, newsid, tclass, FILE__CREATE, &ad); 1865 if (rc) 1866 return rc; 1867 1868 return avc_has_perm(&selinux_state, 1869 newsid, sbsec->sid, 1870 SECCLASS_FILESYSTEM, 1871 FILESYSTEM__ASSOCIATE, &ad); 1872 } 1873 1874 #define MAY_LINK 0 1875 #define MAY_UNLINK 1 1876 #define MAY_RMDIR 2 1877 1878 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1879 static int may_link(struct inode *dir, 1880 struct dentry *dentry, 1881 int kind) 1882 1883 { 1884 struct inode_security_struct *dsec, *isec; 1885 struct common_audit_data ad; 1886 u32 sid = current_sid(); 1887 u32 av; 1888 int rc; 1889 1890 dsec = inode_security(dir); 1891 isec = backing_inode_security(dentry); 1892 1893 ad.type = LSM_AUDIT_DATA_DENTRY; 1894 ad.u.dentry = dentry; 1895 1896 av = DIR__SEARCH; 1897 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1898 rc = avc_has_perm(&selinux_state, 1899 sid, dsec->sid, SECCLASS_DIR, av, &ad); 1900 if (rc) 1901 return rc; 1902 1903 switch (kind) { 1904 case MAY_LINK: 1905 av = FILE__LINK; 1906 break; 1907 case MAY_UNLINK: 1908 av = FILE__UNLINK; 1909 break; 1910 case MAY_RMDIR: 1911 av = DIR__RMDIR; 1912 break; 1913 default: 1914 pr_warn("SELinux: %s: unrecognized kind %d\n", 1915 __func__, kind); 1916 return 0; 1917 } 1918 1919 rc = avc_has_perm(&selinux_state, 1920 sid, isec->sid, isec->sclass, av, &ad); 1921 return rc; 1922 } 1923 1924 static inline int may_rename(struct inode *old_dir, 1925 struct dentry *old_dentry, 1926 struct inode *new_dir, 1927 struct dentry *new_dentry) 1928 { 1929 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1930 struct common_audit_data ad; 1931 u32 sid = current_sid(); 1932 u32 av; 1933 int old_is_dir, new_is_dir; 1934 int rc; 1935 1936 old_dsec = inode_security(old_dir); 1937 old_isec = backing_inode_security(old_dentry); 1938 old_is_dir = d_is_dir(old_dentry); 1939 new_dsec = inode_security(new_dir); 1940 1941 ad.type = LSM_AUDIT_DATA_DENTRY; 1942 1943 ad.u.dentry = old_dentry; 1944 rc = avc_has_perm(&selinux_state, 1945 sid, old_dsec->sid, SECCLASS_DIR, 1946 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1947 if (rc) 1948 return rc; 1949 rc = avc_has_perm(&selinux_state, 1950 sid, old_isec->sid, 1951 old_isec->sclass, FILE__RENAME, &ad); 1952 if (rc) 1953 return rc; 1954 if (old_is_dir && new_dir != old_dir) { 1955 rc = avc_has_perm(&selinux_state, 1956 sid, old_isec->sid, 1957 old_isec->sclass, DIR__REPARENT, &ad); 1958 if (rc) 1959 return rc; 1960 } 1961 1962 ad.u.dentry = new_dentry; 1963 av = DIR__ADD_NAME | DIR__SEARCH; 1964 if (d_is_positive(new_dentry)) 1965 av |= DIR__REMOVE_NAME; 1966 rc = avc_has_perm(&selinux_state, 1967 sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1968 if (rc) 1969 return rc; 1970 if (d_is_positive(new_dentry)) { 1971 new_isec = backing_inode_security(new_dentry); 1972 new_is_dir = d_is_dir(new_dentry); 1973 rc = avc_has_perm(&selinux_state, 1974 sid, new_isec->sid, 1975 new_isec->sclass, 1976 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1977 if (rc) 1978 return rc; 1979 } 1980 1981 return 0; 1982 } 1983 1984 /* Check whether a task can perform a filesystem operation. */ 1985 static int superblock_has_perm(const struct cred *cred, 1986 struct super_block *sb, 1987 u32 perms, 1988 struct common_audit_data *ad) 1989 { 1990 struct superblock_security_struct *sbsec; 1991 u32 sid = cred_sid(cred); 1992 1993 sbsec = selinux_superblock(sb); 1994 return avc_has_perm(&selinux_state, 1995 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1996 } 1997 1998 /* Convert a Linux mode and permission mask to an access vector. */ 1999 static inline u32 file_mask_to_av(int mode, int mask) 2000 { 2001 u32 av = 0; 2002 2003 if (!S_ISDIR(mode)) { 2004 if (mask & MAY_EXEC) 2005 av |= FILE__EXECUTE; 2006 if (mask & MAY_READ) 2007 av |= FILE__READ; 2008 2009 if (mask & MAY_APPEND) 2010 av |= FILE__APPEND; 2011 else if (mask & MAY_WRITE) 2012 av |= FILE__WRITE; 2013 2014 } else { 2015 if (mask & MAY_EXEC) 2016 av |= DIR__SEARCH; 2017 if (mask & MAY_WRITE) 2018 av |= DIR__WRITE; 2019 if (mask & MAY_READ) 2020 av |= DIR__READ; 2021 } 2022 2023 return av; 2024 } 2025 2026 /* Convert a Linux file to an access vector. */ 2027 static inline u32 file_to_av(struct file *file) 2028 { 2029 u32 av = 0; 2030 2031 if (file->f_mode & FMODE_READ) 2032 av |= FILE__READ; 2033 if (file->f_mode & FMODE_WRITE) { 2034 if (file->f_flags & O_APPEND) 2035 av |= FILE__APPEND; 2036 else 2037 av |= FILE__WRITE; 2038 } 2039 if (!av) { 2040 /* 2041 * Special file opened with flags 3 for ioctl-only use. 2042 */ 2043 av = FILE__IOCTL; 2044 } 2045 2046 return av; 2047 } 2048 2049 /* 2050 * Convert a file to an access vector and include the correct 2051 * open permission. 2052 */ 2053 static inline u32 open_file_to_av(struct file *file) 2054 { 2055 u32 av = file_to_av(file); 2056 struct inode *inode = file_inode(file); 2057 2058 if (selinux_policycap_openperm() && 2059 inode->i_sb->s_magic != SOCKFS_MAGIC) 2060 av |= FILE__OPEN; 2061 2062 return av; 2063 } 2064 2065 /* Hook functions begin here. */ 2066 2067 static int selinux_binder_set_context_mgr(struct task_struct *mgr) 2068 { 2069 return avc_has_perm(&selinux_state, 2070 current_sid(), task_sid_binder(mgr), SECCLASS_BINDER, 2071 BINDER__SET_CONTEXT_MGR, NULL); 2072 } 2073 2074 static int selinux_binder_transaction(struct task_struct *from, 2075 struct task_struct *to) 2076 { 2077 u32 mysid = current_sid(); 2078 u32 fromsid = task_sid_binder(from); 2079 int rc; 2080 2081 if (mysid != fromsid) { 2082 rc = avc_has_perm(&selinux_state, 2083 mysid, fromsid, SECCLASS_BINDER, 2084 BINDER__IMPERSONATE, NULL); 2085 if (rc) 2086 return rc; 2087 } 2088 2089 return avc_has_perm(&selinux_state, fromsid, task_sid_binder(to), 2090 SECCLASS_BINDER, BINDER__CALL, NULL); 2091 } 2092 2093 static int selinux_binder_transfer_binder(struct task_struct *from, 2094 struct task_struct *to) 2095 { 2096 return avc_has_perm(&selinux_state, 2097 task_sid_binder(from), task_sid_binder(to), 2098 SECCLASS_BINDER, BINDER__TRANSFER, 2099 NULL); 2100 } 2101 2102 static int selinux_binder_transfer_file(struct task_struct *from, 2103 struct task_struct *to, 2104 struct file *file) 2105 { 2106 u32 sid = task_sid_binder(to); 2107 struct file_security_struct *fsec = selinux_file(file); 2108 struct dentry *dentry = file->f_path.dentry; 2109 struct inode_security_struct *isec; 2110 struct common_audit_data ad; 2111 int rc; 2112 2113 ad.type = LSM_AUDIT_DATA_PATH; 2114 ad.u.path = file->f_path; 2115 2116 if (sid != fsec->sid) { 2117 rc = avc_has_perm(&selinux_state, 2118 sid, fsec->sid, 2119 SECCLASS_FD, 2120 FD__USE, 2121 &ad); 2122 if (rc) 2123 return rc; 2124 } 2125 2126 #ifdef CONFIG_BPF_SYSCALL 2127 rc = bpf_fd_pass(file, sid); 2128 if (rc) 2129 return rc; 2130 #endif 2131 2132 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2133 return 0; 2134 2135 isec = backing_inode_security(dentry); 2136 return avc_has_perm(&selinux_state, 2137 sid, isec->sid, isec->sclass, file_to_av(file), 2138 &ad); 2139 } 2140 2141 static int selinux_ptrace_access_check(struct task_struct *child, 2142 unsigned int mode) 2143 { 2144 u32 sid = current_sid(); 2145 u32 csid = task_sid_obj(child); 2146 2147 if (mode & PTRACE_MODE_READ) 2148 return avc_has_perm(&selinux_state, 2149 sid, csid, SECCLASS_FILE, FILE__READ, NULL); 2150 2151 return avc_has_perm(&selinux_state, 2152 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2153 } 2154 2155 static int selinux_ptrace_traceme(struct task_struct *parent) 2156 { 2157 return avc_has_perm(&selinux_state, 2158 task_sid_subj(parent), task_sid_obj(current), 2159 SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2160 } 2161 2162 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 2163 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2164 { 2165 return avc_has_perm(&selinux_state, 2166 current_sid(), task_sid_obj(target), SECCLASS_PROCESS, 2167 PROCESS__GETCAP, NULL); 2168 } 2169 2170 static int selinux_capset(struct cred *new, const struct cred *old, 2171 const kernel_cap_t *effective, 2172 const kernel_cap_t *inheritable, 2173 const kernel_cap_t *permitted) 2174 { 2175 return avc_has_perm(&selinux_state, 2176 cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2177 PROCESS__SETCAP, NULL); 2178 } 2179 2180 /* 2181 * (This comment used to live with the selinux_task_setuid hook, 2182 * which was removed). 2183 * 2184 * Since setuid only affects the current process, and since the SELinux 2185 * controls are not based on the Linux identity attributes, SELinux does not 2186 * need to control this operation. However, SELinux does control the use of 2187 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2188 */ 2189 2190 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2191 int cap, unsigned int opts) 2192 { 2193 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2194 } 2195 2196 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2197 { 2198 const struct cred *cred = current_cred(); 2199 int rc = 0; 2200 2201 if (!sb) 2202 return 0; 2203 2204 switch (cmds) { 2205 case Q_SYNC: 2206 case Q_QUOTAON: 2207 case Q_QUOTAOFF: 2208 case Q_SETINFO: 2209 case Q_SETQUOTA: 2210 case Q_XQUOTAOFF: 2211 case Q_XQUOTAON: 2212 case Q_XSETQLIM: 2213 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2214 break; 2215 case Q_GETFMT: 2216 case Q_GETINFO: 2217 case Q_GETQUOTA: 2218 case Q_XGETQUOTA: 2219 case Q_XGETQSTAT: 2220 case Q_XGETQSTATV: 2221 case Q_XGETNEXTQUOTA: 2222 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2223 break; 2224 default: 2225 rc = 0; /* let the kernel handle invalid cmds */ 2226 break; 2227 } 2228 return rc; 2229 } 2230 2231 static int selinux_quota_on(struct dentry *dentry) 2232 { 2233 const struct cred *cred = current_cred(); 2234 2235 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2236 } 2237 2238 static int selinux_syslog(int type) 2239 { 2240 switch (type) { 2241 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2242 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2243 return avc_has_perm(&selinux_state, 2244 current_sid(), SECINITSID_KERNEL, 2245 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2246 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2247 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2248 /* Set level of messages printed to console */ 2249 case SYSLOG_ACTION_CONSOLE_LEVEL: 2250 return avc_has_perm(&selinux_state, 2251 current_sid(), SECINITSID_KERNEL, 2252 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2253 NULL); 2254 } 2255 /* All other syslog types */ 2256 return avc_has_perm(&selinux_state, 2257 current_sid(), SECINITSID_KERNEL, 2258 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2259 } 2260 2261 /* 2262 * Check that a process has enough memory to allocate a new virtual 2263 * mapping. 0 means there is enough memory for the allocation to 2264 * succeed and -ENOMEM implies there is not. 2265 * 2266 * Do not audit the selinux permission check, as this is applied to all 2267 * processes that allocate mappings. 2268 */ 2269 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2270 { 2271 int rc, cap_sys_admin = 0; 2272 2273 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2274 CAP_OPT_NOAUDIT, true); 2275 if (rc == 0) 2276 cap_sys_admin = 1; 2277 2278 return cap_sys_admin; 2279 } 2280 2281 /* binprm security operations */ 2282 2283 static u32 ptrace_parent_sid(void) 2284 { 2285 u32 sid = 0; 2286 struct task_struct *tracer; 2287 2288 rcu_read_lock(); 2289 tracer = ptrace_parent(current); 2290 if (tracer) 2291 sid = task_sid_obj(tracer); 2292 rcu_read_unlock(); 2293 2294 return sid; 2295 } 2296 2297 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2298 const struct task_security_struct *old_tsec, 2299 const struct task_security_struct *new_tsec) 2300 { 2301 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2302 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2303 int rc; 2304 u32 av; 2305 2306 if (!nnp && !nosuid) 2307 return 0; /* neither NNP nor nosuid */ 2308 2309 if (new_tsec->sid == old_tsec->sid) 2310 return 0; /* No change in credentials */ 2311 2312 /* 2313 * If the policy enables the nnp_nosuid_transition policy capability, 2314 * then we permit transitions under NNP or nosuid if the 2315 * policy allows the corresponding permission between 2316 * the old and new contexts. 2317 */ 2318 if (selinux_policycap_nnp_nosuid_transition()) { 2319 av = 0; 2320 if (nnp) 2321 av |= PROCESS2__NNP_TRANSITION; 2322 if (nosuid) 2323 av |= PROCESS2__NOSUID_TRANSITION; 2324 rc = avc_has_perm(&selinux_state, 2325 old_tsec->sid, new_tsec->sid, 2326 SECCLASS_PROCESS2, av, NULL); 2327 if (!rc) 2328 return 0; 2329 } 2330 2331 /* 2332 * We also permit NNP or nosuid transitions to bounded SIDs, 2333 * i.e. SIDs that are guaranteed to only be allowed a subset 2334 * of the permissions of the current SID. 2335 */ 2336 rc = security_bounded_transition(&selinux_state, old_tsec->sid, 2337 new_tsec->sid); 2338 if (!rc) 2339 return 0; 2340 2341 /* 2342 * On failure, preserve the errno values for NNP vs nosuid. 2343 * NNP: Operation not permitted for caller. 2344 * nosuid: Permission denied to file. 2345 */ 2346 if (nnp) 2347 return -EPERM; 2348 return -EACCES; 2349 } 2350 2351 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2352 { 2353 const struct task_security_struct *old_tsec; 2354 struct task_security_struct *new_tsec; 2355 struct inode_security_struct *isec; 2356 struct common_audit_data ad; 2357 struct inode *inode = file_inode(bprm->file); 2358 int rc; 2359 2360 /* SELinux context only depends on initial program or script and not 2361 * the script interpreter */ 2362 2363 old_tsec = selinux_cred(current_cred()); 2364 new_tsec = selinux_cred(bprm->cred); 2365 isec = inode_security(inode); 2366 2367 /* Default to the current task SID. */ 2368 new_tsec->sid = old_tsec->sid; 2369 new_tsec->osid = old_tsec->sid; 2370 2371 /* Reset fs, key, and sock SIDs on execve. */ 2372 new_tsec->create_sid = 0; 2373 new_tsec->keycreate_sid = 0; 2374 new_tsec->sockcreate_sid = 0; 2375 2376 if (old_tsec->exec_sid) { 2377 new_tsec->sid = old_tsec->exec_sid; 2378 /* Reset exec SID on execve. */ 2379 new_tsec->exec_sid = 0; 2380 2381 /* Fail on NNP or nosuid if not an allowed transition. */ 2382 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2383 if (rc) 2384 return rc; 2385 } else { 2386 /* Check for a default transition on this program. */ 2387 rc = security_transition_sid(&selinux_state, old_tsec->sid, 2388 isec->sid, SECCLASS_PROCESS, NULL, 2389 &new_tsec->sid); 2390 if (rc) 2391 return rc; 2392 2393 /* 2394 * Fallback to old SID on NNP or nosuid if not an allowed 2395 * transition. 2396 */ 2397 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2398 if (rc) 2399 new_tsec->sid = old_tsec->sid; 2400 } 2401 2402 ad.type = LSM_AUDIT_DATA_FILE; 2403 ad.u.file = bprm->file; 2404 2405 if (new_tsec->sid == old_tsec->sid) { 2406 rc = avc_has_perm(&selinux_state, 2407 old_tsec->sid, isec->sid, 2408 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2409 if (rc) 2410 return rc; 2411 } else { 2412 /* Check permissions for the transition. */ 2413 rc = avc_has_perm(&selinux_state, 2414 old_tsec->sid, new_tsec->sid, 2415 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2416 if (rc) 2417 return rc; 2418 2419 rc = avc_has_perm(&selinux_state, 2420 new_tsec->sid, isec->sid, 2421 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2422 if (rc) 2423 return rc; 2424 2425 /* Check for shared state */ 2426 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2427 rc = avc_has_perm(&selinux_state, 2428 old_tsec->sid, new_tsec->sid, 2429 SECCLASS_PROCESS, PROCESS__SHARE, 2430 NULL); 2431 if (rc) 2432 return -EPERM; 2433 } 2434 2435 /* Make sure that anyone attempting to ptrace over a task that 2436 * changes its SID has the appropriate permit */ 2437 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2438 u32 ptsid = ptrace_parent_sid(); 2439 if (ptsid != 0) { 2440 rc = avc_has_perm(&selinux_state, 2441 ptsid, new_tsec->sid, 2442 SECCLASS_PROCESS, 2443 PROCESS__PTRACE, NULL); 2444 if (rc) 2445 return -EPERM; 2446 } 2447 } 2448 2449 /* Clear any possibly unsafe personality bits on exec: */ 2450 bprm->per_clear |= PER_CLEAR_ON_SETID; 2451 2452 /* Enable secure mode for SIDs transitions unless 2453 the noatsecure permission is granted between 2454 the two SIDs, i.e. ahp returns 0. */ 2455 rc = avc_has_perm(&selinux_state, 2456 old_tsec->sid, new_tsec->sid, 2457 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2458 NULL); 2459 bprm->secureexec |= !!rc; 2460 } 2461 2462 return 0; 2463 } 2464 2465 static int match_file(const void *p, struct file *file, unsigned fd) 2466 { 2467 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2468 } 2469 2470 /* Derived from fs/exec.c:flush_old_files. */ 2471 static inline void flush_unauthorized_files(const struct cred *cred, 2472 struct files_struct *files) 2473 { 2474 struct file *file, *devnull = NULL; 2475 struct tty_struct *tty; 2476 int drop_tty = 0; 2477 unsigned n; 2478 2479 tty = get_current_tty(); 2480 if (tty) { 2481 spin_lock(&tty->files_lock); 2482 if (!list_empty(&tty->tty_files)) { 2483 struct tty_file_private *file_priv; 2484 2485 /* Revalidate access to controlling tty. 2486 Use file_path_has_perm on the tty path directly 2487 rather than using file_has_perm, as this particular 2488 open file may belong to another process and we are 2489 only interested in the inode-based check here. */ 2490 file_priv = list_first_entry(&tty->tty_files, 2491 struct tty_file_private, list); 2492 file = file_priv->file; 2493 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2494 drop_tty = 1; 2495 } 2496 spin_unlock(&tty->files_lock); 2497 tty_kref_put(tty); 2498 } 2499 /* Reset controlling tty. */ 2500 if (drop_tty) 2501 no_tty(); 2502 2503 /* Revalidate access to inherited open files. */ 2504 n = iterate_fd(files, 0, match_file, cred); 2505 if (!n) /* none found? */ 2506 return; 2507 2508 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2509 if (IS_ERR(devnull)) 2510 devnull = NULL; 2511 /* replace all the matching ones with this */ 2512 do { 2513 replace_fd(n - 1, devnull, 0); 2514 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2515 if (devnull) 2516 fput(devnull); 2517 } 2518 2519 /* 2520 * Prepare a process for imminent new credential changes due to exec 2521 */ 2522 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2523 { 2524 struct task_security_struct *new_tsec; 2525 struct rlimit *rlim, *initrlim; 2526 int rc, i; 2527 2528 new_tsec = selinux_cred(bprm->cred); 2529 if (new_tsec->sid == new_tsec->osid) 2530 return; 2531 2532 /* Close files for which the new task SID is not authorized. */ 2533 flush_unauthorized_files(bprm->cred, current->files); 2534 2535 /* Always clear parent death signal on SID transitions. */ 2536 current->pdeath_signal = 0; 2537 2538 /* Check whether the new SID can inherit resource limits from the old 2539 * SID. If not, reset all soft limits to the lower of the current 2540 * task's hard limit and the init task's soft limit. 2541 * 2542 * Note that the setting of hard limits (even to lower them) can be 2543 * controlled by the setrlimit check. The inclusion of the init task's 2544 * soft limit into the computation is to avoid resetting soft limits 2545 * higher than the default soft limit for cases where the default is 2546 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2547 */ 2548 rc = avc_has_perm(&selinux_state, 2549 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2550 PROCESS__RLIMITINH, NULL); 2551 if (rc) { 2552 /* protect against do_prlimit() */ 2553 task_lock(current); 2554 for (i = 0; i < RLIM_NLIMITS; i++) { 2555 rlim = current->signal->rlim + i; 2556 initrlim = init_task.signal->rlim + i; 2557 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2558 } 2559 task_unlock(current); 2560 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2561 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2562 } 2563 } 2564 2565 /* 2566 * Clean up the process immediately after the installation of new credentials 2567 * due to exec 2568 */ 2569 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2570 { 2571 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2572 u32 osid, sid; 2573 int rc; 2574 2575 osid = tsec->osid; 2576 sid = tsec->sid; 2577 2578 if (sid == osid) 2579 return; 2580 2581 /* Check whether the new SID can inherit signal state from the old SID. 2582 * If not, clear itimers to avoid subsequent signal generation and 2583 * flush and unblock signals. 2584 * 2585 * This must occur _after_ the task SID has been updated so that any 2586 * kill done after the flush will be checked against the new SID. 2587 */ 2588 rc = avc_has_perm(&selinux_state, 2589 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2590 if (rc) { 2591 clear_itimer(); 2592 2593 spin_lock_irq(¤t->sighand->siglock); 2594 if (!fatal_signal_pending(current)) { 2595 flush_sigqueue(¤t->pending); 2596 flush_sigqueue(¤t->signal->shared_pending); 2597 flush_signal_handlers(current, 1); 2598 sigemptyset(¤t->blocked); 2599 recalc_sigpending(); 2600 } 2601 spin_unlock_irq(¤t->sighand->siglock); 2602 } 2603 2604 /* Wake up the parent if it is waiting so that it can recheck 2605 * wait permission to the new task SID. */ 2606 read_lock(&tasklist_lock); 2607 __wake_up_parent(current, current->real_parent); 2608 read_unlock(&tasklist_lock); 2609 } 2610 2611 /* superblock security operations */ 2612 2613 static int selinux_sb_alloc_security(struct super_block *sb) 2614 { 2615 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2616 2617 mutex_init(&sbsec->lock); 2618 INIT_LIST_HEAD(&sbsec->isec_head); 2619 spin_lock_init(&sbsec->isec_lock); 2620 sbsec->sid = SECINITSID_UNLABELED; 2621 sbsec->def_sid = SECINITSID_FILE; 2622 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2623 2624 return 0; 2625 } 2626 2627 static inline int opt_len(const char *s) 2628 { 2629 bool open_quote = false; 2630 int len; 2631 char c; 2632 2633 for (len = 0; (c = s[len]) != '\0'; len++) { 2634 if (c == '"') 2635 open_quote = !open_quote; 2636 if (c == ',' && !open_quote) 2637 break; 2638 } 2639 return len; 2640 } 2641 2642 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2643 { 2644 char *from = options; 2645 char *to = options; 2646 bool first = true; 2647 int rc; 2648 2649 while (1) { 2650 int len = opt_len(from); 2651 int token; 2652 char *arg = NULL; 2653 2654 token = match_opt_prefix(from, len, &arg); 2655 2656 if (token != Opt_error) { 2657 char *p, *q; 2658 2659 /* strip quotes */ 2660 if (arg) { 2661 for (p = q = arg; p < from + len; p++) { 2662 char c = *p; 2663 if (c != '"') 2664 *q++ = c; 2665 } 2666 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2667 if (!arg) { 2668 rc = -ENOMEM; 2669 goto free_opt; 2670 } 2671 } 2672 rc = selinux_add_opt(token, arg, mnt_opts); 2673 if (unlikely(rc)) { 2674 kfree(arg); 2675 goto free_opt; 2676 } 2677 } else { 2678 if (!first) { // copy with preceding comma 2679 from--; 2680 len++; 2681 } 2682 if (to != from) 2683 memmove(to, from, len); 2684 to += len; 2685 first = false; 2686 } 2687 if (!from[len]) 2688 break; 2689 from += len + 1; 2690 } 2691 *to = '\0'; 2692 return 0; 2693 2694 free_opt: 2695 if (*mnt_opts) { 2696 selinux_free_mnt_opts(*mnt_opts); 2697 *mnt_opts = NULL; 2698 } 2699 return rc; 2700 } 2701 2702 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2703 { 2704 struct selinux_mnt_opts *opts = mnt_opts; 2705 struct superblock_security_struct *sbsec = sb->s_security; 2706 u32 sid; 2707 int rc; 2708 2709 /* 2710 * Superblock not initialized (i.e. no options) - reject if any 2711 * options specified, otherwise accept. 2712 */ 2713 if (!(sbsec->flags & SE_SBINITIALIZED)) 2714 return opts ? 1 : 0; 2715 2716 /* 2717 * Superblock initialized and no options specified - reject if 2718 * superblock has any options set, otherwise accept. 2719 */ 2720 if (!opts) 2721 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2722 2723 if (opts->fscontext) { 2724 rc = parse_sid(sb, opts->fscontext, &sid); 2725 if (rc) 2726 return 1; 2727 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2728 return 1; 2729 } 2730 if (opts->context) { 2731 rc = parse_sid(sb, opts->context, &sid); 2732 if (rc) 2733 return 1; 2734 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2735 return 1; 2736 } 2737 if (opts->rootcontext) { 2738 struct inode_security_struct *root_isec; 2739 2740 root_isec = backing_inode_security(sb->s_root); 2741 rc = parse_sid(sb, opts->rootcontext, &sid); 2742 if (rc) 2743 return 1; 2744 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2745 return 1; 2746 } 2747 if (opts->defcontext) { 2748 rc = parse_sid(sb, opts->defcontext, &sid); 2749 if (rc) 2750 return 1; 2751 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2752 return 1; 2753 } 2754 return 0; 2755 } 2756 2757 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2758 { 2759 struct selinux_mnt_opts *opts = mnt_opts; 2760 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2761 u32 sid; 2762 int rc; 2763 2764 if (!(sbsec->flags & SE_SBINITIALIZED)) 2765 return 0; 2766 2767 if (!opts) 2768 return 0; 2769 2770 if (opts->fscontext) { 2771 rc = parse_sid(sb, opts->fscontext, &sid); 2772 if (rc) 2773 return rc; 2774 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2775 goto out_bad_option; 2776 } 2777 if (opts->context) { 2778 rc = parse_sid(sb, opts->context, &sid); 2779 if (rc) 2780 return rc; 2781 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2782 goto out_bad_option; 2783 } 2784 if (opts->rootcontext) { 2785 struct inode_security_struct *root_isec; 2786 root_isec = backing_inode_security(sb->s_root); 2787 rc = parse_sid(sb, opts->rootcontext, &sid); 2788 if (rc) 2789 return rc; 2790 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2791 goto out_bad_option; 2792 } 2793 if (opts->defcontext) { 2794 rc = parse_sid(sb, opts->defcontext, &sid); 2795 if (rc) 2796 return rc; 2797 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2798 goto out_bad_option; 2799 } 2800 return 0; 2801 2802 out_bad_option: 2803 pr_warn("SELinux: unable to change security options " 2804 "during remount (dev %s, type=%s)\n", sb->s_id, 2805 sb->s_type->name); 2806 return -EINVAL; 2807 } 2808 2809 static int selinux_sb_kern_mount(struct super_block *sb) 2810 { 2811 const struct cred *cred = current_cred(); 2812 struct common_audit_data ad; 2813 2814 ad.type = LSM_AUDIT_DATA_DENTRY; 2815 ad.u.dentry = sb->s_root; 2816 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2817 } 2818 2819 static int selinux_sb_statfs(struct dentry *dentry) 2820 { 2821 const struct cred *cred = current_cred(); 2822 struct common_audit_data ad; 2823 2824 ad.type = LSM_AUDIT_DATA_DENTRY; 2825 ad.u.dentry = dentry->d_sb->s_root; 2826 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2827 } 2828 2829 static int selinux_mount(const char *dev_name, 2830 const struct path *path, 2831 const char *type, 2832 unsigned long flags, 2833 void *data) 2834 { 2835 const struct cred *cred = current_cred(); 2836 2837 if (flags & MS_REMOUNT) 2838 return superblock_has_perm(cred, path->dentry->d_sb, 2839 FILESYSTEM__REMOUNT, NULL); 2840 else 2841 return path_has_perm(cred, path, FILE__MOUNTON); 2842 } 2843 2844 static int selinux_move_mount(const struct path *from_path, 2845 const struct path *to_path) 2846 { 2847 const struct cred *cred = current_cred(); 2848 2849 return path_has_perm(cred, to_path, FILE__MOUNTON); 2850 } 2851 2852 static int selinux_umount(struct vfsmount *mnt, int flags) 2853 { 2854 const struct cred *cred = current_cred(); 2855 2856 return superblock_has_perm(cred, mnt->mnt_sb, 2857 FILESYSTEM__UNMOUNT, NULL); 2858 } 2859 2860 static int selinux_fs_context_dup(struct fs_context *fc, 2861 struct fs_context *src_fc) 2862 { 2863 const struct selinux_mnt_opts *src = src_fc->security; 2864 struct selinux_mnt_opts *opts; 2865 2866 if (!src) 2867 return 0; 2868 2869 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); 2870 if (!fc->security) 2871 return -ENOMEM; 2872 2873 opts = fc->security; 2874 2875 if (src->fscontext) { 2876 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); 2877 if (!opts->fscontext) 2878 return -ENOMEM; 2879 } 2880 if (src->context) { 2881 opts->context = kstrdup(src->context, GFP_KERNEL); 2882 if (!opts->context) 2883 return -ENOMEM; 2884 } 2885 if (src->rootcontext) { 2886 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); 2887 if (!opts->rootcontext) 2888 return -ENOMEM; 2889 } 2890 if (src->defcontext) { 2891 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); 2892 if (!opts->defcontext) 2893 return -ENOMEM; 2894 } 2895 return 0; 2896 } 2897 2898 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2899 fsparam_string(CONTEXT_STR, Opt_context), 2900 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2901 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2902 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2903 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2904 {} 2905 }; 2906 2907 static int selinux_fs_context_parse_param(struct fs_context *fc, 2908 struct fs_parameter *param) 2909 { 2910 struct fs_parse_result result; 2911 int opt, rc; 2912 2913 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2914 if (opt < 0) 2915 return opt; 2916 2917 rc = selinux_add_opt(opt, param->string, &fc->security); 2918 if (!rc) { 2919 param->string = NULL; 2920 rc = 1; 2921 } 2922 return rc; 2923 } 2924 2925 /* inode security operations */ 2926 2927 static int selinux_inode_alloc_security(struct inode *inode) 2928 { 2929 struct inode_security_struct *isec = selinux_inode(inode); 2930 u32 sid = current_sid(); 2931 2932 spin_lock_init(&isec->lock); 2933 INIT_LIST_HEAD(&isec->list); 2934 isec->inode = inode; 2935 isec->sid = SECINITSID_UNLABELED; 2936 isec->sclass = SECCLASS_FILE; 2937 isec->task_sid = sid; 2938 isec->initialized = LABEL_INVALID; 2939 2940 return 0; 2941 } 2942 2943 static void selinux_inode_free_security(struct inode *inode) 2944 { 2945 inode_free_security(inode); 2946 } 2947 2948 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2949 const struct qstr *name, void **ctx, 2950 u32 *ctxlen) 2951 { 2952 u32 newsid; 2953 int rc; 2954 2955 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2956 d_inode(dentry->d_parent), name, 2957 inode_mode_to_security_class(mode), 2958 &newsid); 2959 if (rc) 2960 return rc; 2961 2962 return security_sid_to_context(&selinux_state, newsid, (char **)ctx, 2963 ctxlen); 2964 } 2965 2966 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2967 struct qstr *name, 2968 const struct cred *old, 2969 struct cred *new) 2970 { 2971 u32 newsid; 2972 int rc; 2973 struct task_security_struct *tsec; 2974 2975 rc = selinux_determine_inode_label(selinux_cred(old), 2976 d_inode(dentry->d_parent), name, 2977 inode_mode_to_security_class(mode), 2978 &newsid); 2979 if (rc) 2980 return rc; 2981 2982 tsec = selinux_cred(new); 2983 tsec->create_sid = newsid; 2984 return 0; 2985 } 2986 2987 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2988 const struct qstr *qstr, 2989 const char **name, 2990 void **value, size_t *len) 2991 { 2992 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2993 struct superblock_security_struct *sbsec; 2994 u32 newsid, clen; 2995 int rc; 2996 char *context; 2997 2998 sbsec = selinux_superblock(dir->i_sb); 2999 3000 newsid = tsec->create_sid; 3001 3002 rc = selinux_determine_inode_label(tsec, dir, qstr, 3003 inode_mode_to_security_class(inode->i_mode), 3004 &newsid); 3005 if (rc) 3006 return rc; 3007 3008 /* Possibly defer initialization to selinux_complete_init. */ 3009 if (sbsec->flags & SE_SBINITIALIZED) { 3010 struct inode_security_struct *isec = selinux_inode(inode); 3011 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3012 isec->sid = newsid; 3013 isec->initialized = LABEL_INITIALIZED; 3014 } 3015 3016 if (!selinux_initialized(&selinux_state) || 3017 !(sbsec->flags & SBLABEL_MNT)) 3018 return -EOPNOTSUPP; 3019 3020 if (name) 3021 *name = XATTR_SELINUX_SUFFIX; 3022 3023 if (value && len) { 3024 rc = security_sid_to_context_force(&selinux_state, newsid, 3025 &context, &clen); 3026 if (rc) 3027 return rc; 3028 *value = context; 3029 *len = clen; 3030 } 3031 3032 return 0; 3033 } 3034 3035 static int selinux_inode_init_security_anon(struct inode *inode, 3036 const struct qstr *name, 3037 const struct inode *context_inode) 3038 { 3039 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3040 struct common_audit_data ad; 3041 struct inode_security_struct *isec; 3042 int rc; 3043 3044 if (unlikely(!selinux_initialized(&selinux_state))) 3045 return 0; 3046 3047 isec = selinux_inode(inode); 3048 3049 /* 3050 * We only get here once per ephemeral inode. The inode has 3051 * been initialized via inode_alloc_security but is otherwise 3052 * untouched. 3053 */ 3054 3055 if (context_inode) { 3056 struct inode_security_struct *context_isec = 3057 selinux_inode(context_inode); 3058 if (context_isec->initialized != LABEL_INITIALIZED) { 3059 pr_err("SELinux: context_inode is not initialized"); 3060 return -EACCES; 3061 } 3062 3063 isec->sclass = context_isec->sclass; 3064 isec->sid = context_isec->sid; 3065 } else { 3066 isec->sclass = SECCLASS_ANON_INODE; 3067 rc = security_transition_sid( 3068 &selinux_state, tsec->sid, tsec->sid, 3069 isec->sclass, name, &isec->sid); 3070 if (rc) 3071 return rc; 3072 } 3073 3074 isec->initialized = LABEL_INITIALIZED; 3075 /* 3076 * Now that we've initialized security, check whether we're 3077 * allowed to actually create this type of anonymous inode. 3078 */ 3079 3080 ad.type = LSM_AUDIT_DATA_INODE; 3081 ad.u.inode = inode; 3082 3083 return avc_has_perm(&selinux_state, 3084 tsec->sid, 3085 isec->sid, 3086 isec->sclass, 3087 FILE__CREATE, 3088 &ad); 3089 } 3090 3091 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3092 { 3093 return may_create(dir, dentry, SECCLASS_FILE); 3094 } 3095 3096 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3097 { 3098 return may_link(dir, old_dentry, MAY_LINK); 3099 } 3100 3101 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3102 { 3103 return may_link(dir, dentry, MAY_UNLINK); 3104 } 3105 3106 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3107 { 3108 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3109 } 3110 3111 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3112 { 3113 return may_create(dir, dentry, SECCLASS_DIR); 3114 } 3115 3116 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3117 { 3118 return may_link(dir, dentry, MAY_RMDIR); 3119 } 3120 3121 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3122 { 3123 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3124 } 3125 3126 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3127 struct inode *new_inode, struct dentry *new_dentry) 3128 { 3129 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3130 } 3131 3132 static int selinux_inode_readlink(struct dentry *dentry) 3133 { 3134 const struct cred *cred = current_cred(); 3135 3136 return dentry_has_perm(cred, dentry, FILE__READ); 3137 } 3138 3139 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3140 bool rcu) 3141 { 3142 const struct cred *cred = current_cred(); 3143 struct common_audit_data ad; 3144 struct inode_security_struct *isec; 3145 u32 sid; 3146 3147 validate_creds(cred); 3148 3149 ad.type = LSM_AUDIT_DATA_DENTRY; 3150 ad.u.dentry = dentry; 3151 sid = cred_sid(cred); 3152 isec = inode_security_rcu(inode, rcu); 3153 if (IS_ERR(isec)) 3154 return PTR_ERR(isec); 3155 3156 return avc_has_perm_flags(&selinux_state, 3157 sid, isec->sid, isec->sclass, FILE__READ, &ad, 3158 rcu ? MAY_NOT_BLOCK : 0); 3159 } 3160 3161 static noinline int audit_inode_permission(struct inode *inode, 3162 u32 perms, u32 audited, u32 denied, 3163 int result) 3164 { 3165 struct common_audit_data ad; 3166 struct inode_security_struct *isec = selinux_inode(inode); 3167 int rc; 3168 3169 ad.type = LSM_AUDIT_DATA_INODE; 3170 ad.u.inode = inode; 3171 3172 rc = slow_avc_audit(&selinux_state, 3173 current_sid(), isec->sid, isec->sclass, perms, 3174 audited, denied, result, &ad); 3175 if (rc) 3176 return rc; 3177 return 0; 3178 } 3179 3180 static int selinux_inode_permission(struct inode *inode, int mask) 3181 { 3182 const struct cred *cred = current_cred(); 3183 u32 perms; 3184 bool from_access; 3185 bool no_block = mask & MAY_NOT_BLOCK; 3186 struct inode_security_struct *isec; 3187 u32 sid; 3188 struct av_decision avd; 3189 int rc, rc2; 3190 u32 audited, denied; 3191 3192 from_access = mask & MAY_ACCESS; 3193 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3194 3195 /* No permission to check. Existence test. */ 3196 if (!mask) 3197 return 0; 3198 3199 validate_creds(cred); 3200 3201 if (unlikely(IS_PRIVATE(inode))) 3202 return 0; 3203 3204 perms = file_mask_to_av(inode->i_mode, mask); 3205 3206 sid = cred_sid(cred); 3207 isec = inode_security_rcu(inode, no_block); 3208 if (IS_ERR(isec)) 3209 return PTR_ERR(isec); 3210 3211 rc = avc_has_perm_noaudit(&selinux_state, 3212 sid, isec->sid, isec->sclass, perms, 3213 no_block ? AVC_NONBLOCKING : 0, 3214 &avd); 3215 audited = avc_audit_required(perms, &avd, rc, 3216 from_access ? FILE__AUDIT_ACCESS : 0, 3217 &denied); 3218 if (likely(!audited)) 3219 return rc; 3220 3221 /* fall back to ref-walk if we have to generate audit */ 3222 if (no_block) 3223 return -ECHILD; 3224 3225 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3226 if (rc2) 3227 return rc2; 3228 return rc; 3229 } 3230 3231 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3232 { 3233 const struct cred *cred = current_cred(); 3234 struct inode *inode = d_backing_inode(dentry); 3235 unsigned int ia_valid = iattr->ia_valid; 3236 __u32 av = FILE__WRITE; 3237 3238 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3239 if (ia_valid & ATTR_FORCE) { 3240 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3241 ATTR_FORCE); 3242 if (!ia_valid) 3243 return 0; 3244 } 3245 3246 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3247 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3248 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3249 3250 if (selinux_policycap_openperm() && 3251 inode->i_sb->s_magic != SOCKFS_MAGIC && 3252 (ia_valid & ATTR_SIZE) && 3253 !(ia_valid & ATTR_FILE)) 3254 av |= FILE__OPEN; 3255 3256 return dentry_has_perm(cred, dentry, av); 3257 } 3258 3259 static int selinux_inode_getattr(const struct path *path) 3260 { 3261 return path_has_perm(current_cred(), path, FILE__GETATTR); 3262 } 3263 3264 static bool has_cap_mac_admin(bool audit) 3265 { 3266 const struct cred *cred = current_cred(); 3267 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3268 3269 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3270 return false; 3271 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3272 return false; 3273 return true; 3274 } 3275 3276 static int selinux_inode_setxattr(struct user_namespace *mnt_userns, 3277 struct dentry *dentry, const char *name, 3278 const void *value, size_t size, int flags) 3279 { 3280 struct inode *inode = d_backing_inode(dentry); 3281 struct inode_security_struct *isec; 3282 struct superblock_security_struct *sbsec; 3283 struct common_audit_data ad; 3284 u32 newsid, sid = current_sid(); 3285 int rc = 0; 3286 3287 if (strcmp(name, XATTR_NAME_SELINUX)) { 3288 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3289 if (rc) 3290 return rc; 3291 3292 /* Not an attribute we recognize, so just check the 3293 ordinary setattr permission. */ 3294 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3295 } 3296 3297 if (!selinux_initialized(&selinux_state)) 3298 return (inode_owner_or_capable(mnt_userns, inode) ? 0 : -EPERM); 3299 3300 sbsec = selinux_superblock(inode->i_sb); 3301 if (!(sbsec->flags & SBLABEL_MNT)) 3302 return -EOPNOTSUPP; 3303 3304 if (!inode_owner_or_capable(mnt_userns, inode)) 3305 return -EPERM; 3306 3307 ad.type = LSM_AUDIT_DATA_DENTRY; 3308 ad.u.dentry = dentry; 3309 3310 isec = backing_inode_security(dentry); 3311 rc = avc_has_perm(&selinux_state, 3312 sid, isec->sid, isec->sclass, 3313 FILE__RELABELFROM, &ad); 3314 if (rc) 3315 return rc; 3316 3317 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3318 GFP_KERNEL); 3319 if (rc == -EINVAL) { 3320 if (!has_cap_mac_admin(true)) { 3321 struct audit_buffer *ab; 3322 size_t audit_size; 3323 3324 /* We strip a nul only if it is at the end, otherwise the 3325 * context contains a nul and we should audit that */ 3326 if (value) { 3327 const char *str = value; 3328 3329 if (str[size - 1] == '\0') 3330 audit_size = size - 1; 3331 else 3332 audit_size = size; 3333 } else { 3334 audit_size = 0; 3335 } 3336 ab = audit_log_start(audit_context(), 3337 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3338 audit_log_format(ab, "op=setxattr invalid_context="); 3339 audit_log_n_untrustedstring(ab, value, audit_size); 3340 audit_log_end(ab); 3341 3342 return rc; 3343 } 3344 rc = security_context_to_sid_force(&selinux_state, value, 3345 size, &newsid); 3346 } 3347 if (rc) 3348 return rc; 3349 3350 rc = avc_has_perm(&selinux_state, 3351 sid, newsid, isec->sclass, 3352 FILE__RELABELTO, &ad); 3353 if (rc) 3354 return rc; 3355 3356 rc = security_validate_transition(&selinux_state, isec->sid, newsid, 3357 sid, isec->sclass); 3358 if (rc) 3359 return rc; 3360 3361 return avc_has_perm(&selinux_state, 3362 newsid, 3363 sbsec->sid, 3364 SECCLASS_FILESYSTEM, 3365 FILESYSTEM__ASSOCIATE, 3366 &ad); 3367 } 3368 3369 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3370 const void *value, size_t size, 3371 int flags) 3372 { 3373 struct inode *inode = d_backing_inode(dentry); 3374 struct inode_security_struct *isec; 3375 u32 newsid; 3376 int rc; 3377 3378 if (strcmp(name, XATTR_NAME_SELINUX)) { 3379 /* Not an attribute we recognize, so nothing to do. */ 3380 return; 3381 } 3382 3383 if (!selinux_initialized(&selinux_state)) { 3384 /* If we haven't even been initialized, then we can't validate 3385 * against a policy, so leave the label as invalid. It may 3386 * resolve to a valid label on the next revalidation try if 3387 * we've since initialized. 3388 */ 3389 return; 3390 } 3391 3392 rc = security_context_to_sid_force(&selinux_state, value, size, 3393 &newsid); 3394 if (rc) { 3395 pr_err("SELinux: unable to map context to SID" 3396 "for (%s, %lu), rc=%d\n", 3397 inode->i_sb->s_id, inode->i_ino, -rc); 3398 return; 3399 } 3400 3401 isec = backing_inode_security(dentry); 3402 spin_lock(&isec->lock); 3403 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3404 isec->sid = newsid; 3405 isec->initialized = LABEL_INITIALIZED; 3406 spin_unlock(&isec->lock); 3407 3408 return; 3409 } 3410 3411 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3412 { 3413 const struct cred *cred = current_cred(); 3414 3415 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3416 } 3417 3418 static int selinux_inode_listxattr(struct dentry *dentry) 3419 { 3420 const struct cred *cred = current_cred(); 3421 3422 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3423 } 3424 3425 static int selinux_inode_removexattr(struct user_namespace *mnt_userns, 3426 struct dentry *dentry, const char *name) 3427 { 3428 if (strcmp(name, XATTR_NAME_SELINUX)) { 3429 int rc = cap_inode_removexattr(mnt_userns, dentry, name); 3430 if (rc) 3431 return rc; 3432 3433 /* Not an attribute we recognize, so just check the 3434 ordinary setattr permission. */ 3435 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3436 } 3437 3438 if (!selinux_initialized(&selinux_state)) 3439 return 0; 3440 3441 /* No one is allowed to remove a SELinux security label. 3442 You can change the label, but all data must be labeled. */ 3443 return -EACCES; 3444 } 3445 3446 static int selinux_path_notify(const struct path *path, u64 mask, 3447 unsigned int obj_type) 3448 { 3449 int ret; 3450 u32 perm; 3451 3452 struct common_audit_data ad; 3453 3454 ad.type = LSM_AUDIT_DATA_PATH; 3455 ad.u.path = *path; 3456 3457 /* 3458 * Set permission needed based on the type of mark being set. 3459 * Performs an additional check for sb watches. 3460 */ 3461 switch (obj_type) { 3462 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3463 perm = FILE__WATCH_MOUNT; 3464 break; 3465 case FSNOTIFY_OBJ_TYPE_SB: 3466 perm = FILE__WATCH_SB; 3467 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3468 FILESYSTEM__WATCH, &ad); 3469 if (ret) 3470 return ret; 3471 break; 3472 case FSNOTIFY_OBJ_TYPE_INODE: 3473 perm = FILE__WATCH; 3474 break; 3475 default: 3476 return -EINVAL; 3477 } 3478 3479 /* blocking watches require the file:watch_with_perm permission */ 3480 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3481 perm |= FILE__WATCH_WITH_PERM; 3482 3483 /* watches on read-like events need the file:watch_reads permission */ 3484 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3485 perm |= FILE__WATCH_READS; 3486 3487 return path_has_perm(current_cred(), path, perm); 3488 } 3489 3490 /* 3491 * Copy the inode security context value to the user. 3492 * 3493 * Permission check is handled by selinux_inode_getxattr hook. 3494 */ 3495 static int selinux_inode_getsecurity(struct user_namespace *mnt_userns, 3496 struct inode *inode, const char *name, 3497 void **buffer, bool alloc) 3498 { 3499 u32 size; 3500 int error; 3501 char *context = NULL; 3502 struct inode_security_struct *isec; 3503 3504 /* 3505 * If we're not initialized yet, then we can't validate contexts, so 3506 * just let vfs_getxattr fall back to using the on-disk xattr. 3507 */ 3508 if (!selinux_initialized(&selinux_state) || 3509 strcmp(name, XATTR_SELINUX_SUFFIX)) 3510 return -EOPNOTSUPP; 3511 3512 /* 3513 * If the caller has CAP_MAC_ADMIN, then get the raw context 3514 * value even if it is not defined by current policy; otherwise, 3515 * use the in-core value under current policy. 3516 * Use the non-auditing forms of the permission checks since 3517 * getxattr may be called by unprivileged processes commonly 3518 * and lack of permission just means that we fall back to the 3519 * in-core context value, not a denial. 3520 */ 3521 isec = inode_security(inode); 3522 if (has_cap_mac_admin(false)) 3523 error = security_sid_to_context_force(&selinux_state, 3524 isec->sid, &context, 3525 &size); 3526 else 3527 error = security_sid_to_context(&selinux_state, isec->sid, 3528 &context, &size); 3529 if (error) 3530 return error; 3531 error = size; 3532 if (alloc) { 3533 *buffer = context; 3534 goto out_nofree; 3535 } 3536 kfree(context); 3537 out_nofree: 3538 return error; 3539 } 3540 3541 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3542 const void *value, size_t size, int flags) 3543 { 3544 struct inode_security_struct *isec = inode_security_novalidate(inode); 3545 struct superblock_security_struct *sbsec; 3546 u32 newsid; 3547 int rc; 3548 3549 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3550 return -EOPNOTSUPP; 3551 3552 sbsec = selinux_superblock(inode->i_sb); 3553 if (!(sbsec->flags & SBLABEL_MNT)) 3554 return -EOPNOTSUPP; 3555 3556 if (!value || !size) 3557 return -EACCES; 3558 3559 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3560 GFP_KERNEL); 3561 if (rc) 3562 return rc; 3563 3564 spin_lock(&isec->lock); 3565 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3566 isec->sid = newsid; 3567 isec->initialized = LABEL_INITIALIZED; 3568 spin_unlock(&isec->lock); 3569 return 0; 3570 } 3571 3572 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3573 { 3574 const int len = sizeof(XATTR_NAME_SELINUX); 3575 3576 if (!selinux_initialized(&selinux_state)) 3577 return 0; 3578 3579 if (buffer && len <= buffer_size) 3580 memcpy(buffer, XATTR_NAME_SELINUX, len); 3581 return len; 3582 } 3583 3584 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3585 { 3586 struct inode_security_struct *isec = inode_security_novalidate(inode); 3587 *secid = isec->sid; 3588 } 3589 3590 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3591 { 3592 u32 sid; 3593 struct task_security_struct *tsec; 3594 struct cred *new_creds = *new; 3595 3596 if (new_creds == NULL) { 3597 new_creds = prepare_creds(); 3598 if (!new_creds) 3599 return -ENOMEM; 3600 } 3601 3602 tsec = selinux_cred(new_creds); 3603 /* Get label from overlay inode and set it in create_sid */ 3604 selinux_inode_getsecid(d_inode(src), &sid); 3605 tsec->create_sid = sid; 3606 *new = new_creds; 3607 return 0; 3608 } 3609 3610 static int selinux_inode_copy_up_xattr(const char *name) 3611 { 3612 /* The copy_up hook above sets the initial context on an inode, but we 3613 * don't then want to overwrite it by blindly copying all the lower 3614 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3615 */ 3616 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3617 return 1; /* Discard */ 3618 /* 3619 * Any other attribute apart from SELINUX is not claimed, supported 3620 * by selinux. 3621 */ 3622 return -EOPNOTSUPP; 3623 } 3624 3625 /* kernfs node operations */ 3626 3627 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3628 struct kernfs_node *kn) 3629 { 3630 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3631 u32 parent_sid, newsid, clen; 3632 int rc; 3633 char *context; 3634 3635 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3636 if (rc == -ENODATA) 3637 return 0; 3638 else if (rc < 0) 3639 return rc; 3640 3641 clen = (u32)rc; 3642 context = kmalloc(clen, GFP_KERNEL); 3643 if (!context) 3644 return -ENOMEM; 3645 3646 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3647 if (rc < 0) { 3648 kfree(context); 3649 return rc; 3650 } 3651 3652 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, 3653 GFP_KERNEL); 3654 kfree(context); 3655 if (rc) 3656 return rc; 3657 3658 if (tsec->create_sid) { 3659 newsid = tsec->create_sid; 3660 } else { 3661 u16 secclass = inode_mode_to_security_class(kn->mode); 3662 struct qstr q; 3663 3664 q.name = kn->name; 3665 q.hash_len = hashlen_string(kn_dir, kn->name); 3666 3667 rc = security_transition_sid(&selinux_state, tsec->sid, 3668 parent_sid, secclass, &q, 3669 &newsid); 3670 if (rc) 3671 return rc; 3672 } 3673 3674 rc = security_sid_to_context_force(&selinux_state, newsid, 3675 &context, &clen); 3676 if (rc) 3677 return rc; 3678 3679 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3680 XATTR_CREATE); 3681 kfree(context); 3682 return rc; 3683 } 3684 3685 3686 /* file security operations */ 3687 3688 static int selinux_revalidate_file_permission(struct file *file, int mask) 3689 { 3690 const struct cred *cred = current_cred(); 3691 struct inode *inode = file_inode(file); 3692 3693 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3694 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3695 mask |= MAY_APPEND; 3696 3697 return file_has_perm(cred, file, 3698 file_mask_to_av(inode->i_mode, mask)); 3699 } 3700 3701 static int selinux_file_permission(struct file *file, int mask) 3702 { 3703 struct inode *inode = file_inode(file); 3704 struct file_security_struct *fsec = selinux_file(file); 3705 struct inode_security_struct *isec; 3706 u32 sid = current_sid(); 3707 3708 if (!mask) 3709 /* No permission to check. Existence test. */ 3710 return 0; 3711 3712 isec = inode_security(inode); 3713 if (sid == fsec->sid && fsec->isid == isec->sid && 3714 fsec->pseqno == avc_policy_seqno(&selinux_state)) 3715 /* No change since file_open check. */ 3716 return 0; 3717 3718 return selinux_revalidate_file_permission(file, mask); 3719 } 3720 3721 static int selinux_file_alloc_security(struct file *file) 3722 { 3723 struct file_security_struct *fsec = selinux_file(file); 3724 u32 sid = current_sid(); 3725 3726 fsec->sid = sid; 3727 fsec->fown_sid = sid; 3728 3729 return 0; 3730 } 3731 3732 /* 3733 * Check whether a task has the ioctl permission and cmd 3734 * operation to an inode. 3735 */ 3736 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3737 u32 requested, u16 cmd) 3738 { 3739 struct common_audit_data ad; 3740 struct file_security_struct *fsec = selinux_file(file); 3741 struct inode *inode = file_inode(file); 3742 struct inode_security_struct *isec; 3743 struct lsm_ioctlop_audit ioctl; 3744 u32 ssid = cred_sid(cred); 3745 int rc; 3746 u8 driver = cmd >> 8; 3747 u8 xperm = cmd & 0xff; 3748 3749 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3750 ad.u.op = &ioctl; 3751 ad.u.op->cmd = cmd; 3752 ad.u.op->path = file->f_path; 3753 3754 if (ssid != fsec->sid) { 3755 rc = avc_has_perm(&selinux_state, 3756 ssid, fsec->sid, 3757 SECCLASS_FD, 3758 FD__USE, 3759 &ad); 3760 if (rc) 3761 goto out; 3762 } 3763 3764 if (unlikely(IS_PRIVATE(inode))) 3765 return 0; 3766 3767 isec = inode_security(inode); 3768 rc = avc_has_extended_perms(&selinux_state, 3769 ssid, isec->sid, isec->sclass, 3770 requested, driver, xperm, &ad); 3771 out: 3772 return rc; 3773 } 3774 3775 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3776 unsigned long arg) 3777 { 3778 const struct cred *cred = current_cred(); 3779 int error = 0; 3780 3781 switch (cmd) { 3782 case FIONREAD: 3783 case FIBMAP: 3784 case FIGETBSZ: 3785 case FS_IOC_GETFLAGS: 3786 case FS_IOC_GETVERSION: 3787 error = file_has_perm(cred, file, FILE__GETATTR); 3788 break; 3789 3790 case FS_IOC_SETFLAGS: 3791 case FS_IOC_SETVERSION: 3792 error = file_has_perm(cred, file, FILE__SETATTR); 3793 break; 3794 3795 /* sys_ioctl() checks */ 3796 case FIONBIO: 3797 case FIOASYNC: 3798 error = file_has_perm(cred, file, 0); 3799 break; 3800 3801 case KDSKBENT: 3802 case KDSKBSENT: 3803 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3804 CAP_OPT_NONE, true); 3805 break; 3806 3807 /* default case assumes that the command will go 3808 * to the file's ioctl() function. 3809 */ 3810 default: 3811 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3812 } 3813 return error; 3814 } 3815 3816 static int default_noexec __ro_after_init; 3817 3818 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3819 { 3820 const struct cred *cred = current_cred(); 3821 u32 sid = cred_sid(cred); 3822 int rc = 0; 3823 3824 if (default_noexec && 3825 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3826 (!shared && (prot & PROT_WRITE)))) { 3827 /* 3828 * We are making executable an anonymous mapping or a 3829 * private file mapping that will also be writable. 3830 * This has an additional check. 3831 */ 3832 rc = avc_has_perm(&selinux_state, 3833 sid, sid, SECCLASS_PROCESS, 3834 PROCESS__EXECMEM, NULL); 3835 if (rc) 3836 goto error; 3837 } 3838 3839 if (file) { 3840 /* read access is always possible with a mapping */ 3841 u32 av = FILE__READ; 3842 3843 /* write access only matters if the mapping is shared */ 3844 if (shared && (prot & PROT_WRITE)) 3845 av |= FILE__WRITE; 3846 3847 if (prot & PROT_EXEC) 3848 av |= FILE__EXECUTE; 3849 3850 return file_has_perm(cred, file, av); 3851 } 3852 3853 error: 3854 return rc; 3855 } 3856 3857 static int selinux_mmap_addr(unsigned long addr) 3858 { 3859 int rc = 0; 3860 3861 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3862 u32 sid = current_sid(); 3863 rc = avc_has_perm(&selinux_state, 3864 sid, sid, SECCLASS_MEMPROTECT, 3865 MEMPROTECT__MMAP_ZERO, NULL); 3866 } 3867 3868 return rc; 3869 } 3870 3871 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3872 unsigned long prot, unsigned long flags) 3873 { 3874 struct common_audit_data ad; 3875 int rc; 3876 3877 if (file) { 3878 ad.type = LSM_AUDIT_DATA_FILE; 3879 ad.u.file = file; 3880 rc = inode_has_perm(current_cred(), file_inode(file), 3881 FILE__MAP, &ad); 3882 if (rc) 3883 return rc; 3884 } 3885 3886 if (checkreqprot_get(&selinux_state)) 3887 prot = reqprot; 3888 3889 return file_map_prot_check(file, prot, 3890 (flags & MAP_TYPE) == MAP_SHARED); 3891 } 3892 3893 static int selinux_file_mprotect(struct vm_area_struct *vma, 3894 unsigned long reqprot, 3895 unsigned long prot) 3896 { 3897 const struct cred *cred = current_cred(); 3898 u32 sid = cred_sid(cred); 3899 3900 if (checkreqprot_get(&selinux_state)) 3901 prot = reqprot; 3902 3903 if (default_noexec && 3904 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3905 int rc = 0; 3906 if (vma->vm_start >= vma->vm_mm->start_brk && 3907 vma->vm_end <= vma->vm_mm->brk) { 3908 rc = avc_has_perm(&selinux_state, 3909 sid, sid, SECCLASS_PROCESS, 3910 PROCESS__EXECHEAP, NULL); 3911 } else if (!vma->vm_file && 3912 ((vma->vm_start <= vma->vm_mm->start_stack && 3913 vma->vm_end >= vma->vm_mm->start_stack) || 3914 vma_is_stack_for_current(vma))) { 3915 rc = avc_has_perm(&selinux_state, 3916 sid, sid, SECCLASS_PROCESS, 3917 PROCESS__EXECSTACK, NULL); 3918 } else if (vma->vm_file && vma->anon_vma) { 3919 /* 3920 * We are making executable a file mapping that has 3921 * had some COW done. Since pages might have been 3922 * written, check ability to execute the possibly 3923 * modified content. This typically should only 3924 * occur for text relocations. 3925 */ 3926 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3927 } 3928 if (rc) 3929 return rc; 3930 } 3931 3932 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3933 } 3934 3935 static int selinux_file_lock(struct file *file, unsigned int cmd) 3936 { 3937 const struct cred *cred = current_cred(); 3938 3939 return file_has_perm(cred, file, FILE__LOCK); 3940 } 3941 3942 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3943 unsigned long arg) 3944 { 3945 const struct cred *cred = current_cred(); 3946 int err = 0; 3947 3948 switch (cmd) { 3949 case F_SETFL: 3950 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3951 err = file_has_perm(cred, file, FILE__WRITE); 3952 break; 3953 } 3954 fallthrough; 3955 case F_SETOWN: 3956 case F_SETSIG: 3957 case F_GETFL: 3958 case F_GETOWN: 3959 case F_GETSIG: 3960 case F_GETOWNER_UIDS: 3961 /* Just check FD__USE permission */ 3962 err = file_has_perm(cred, file, 0); 3963 break; 3964 case F_GETLK: 3965 case F_SETLK: 3966 case F_SETLKW: 3967 case F_OFD_GETLK: 3968 case F_OFD_SETLK: 3969 case F_OFD_SETLKW: 3970 #if BITS_PER_LONG == 32 3971 case F_GETLK64: 3972 case F_SETLK64: 3973 case F_SETLKW64: 3974 #endif 3975 err = file_has_perm(cred, file, FILE__LOCK); 3976 break; 3977 } 3978 3979 return err; 3980 } 3981 3982 static void selinux_file_set_fowner(struct file *file) 3983 { 3984 struct file_security_struct *fsec; 3985 3986 fsec = selinux_file(file); 3987 fsec->fown_sid = current_sid(); 3988 } 3989 3990 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3991 struct fown_struct *fown, int signum) 3992 { 3993 struct file *file; 3994 u32 sid = task_sid_obj(tsk); 3995 u32 perm; 3996 struct file_security_struct *fsec; 3997 3998 /* struct fown_struct is never outside the context of a struct file */ 3999 file = container_of(fown, struct file, f_owner); 4000 4001 fsec = selinux_file(file); 4002 4003 if (!signum) 4004 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 4005 else 4006 perm = signal_to_av(signum); 4007 4008 return avc_has_perm(&selinux_state, 4009 fsec->fown_sid, sid, 4010 SECCLASS_PROCESS, perm, NULL); 4011 } 4012 4013 static int selinux_file_receive(struct file *file) 4014 { 4015 const struct cred *cred = current_cred(); 4016 4017 return file_has_perm(cred, file, file_to_av(file)); 4018 } 4019 4020 static int selinux_file_open(struct file *file) 4021 { 4022 struct file_security_struct *fsec; 4023 struct inode_security_struct *isec; 4024 4025 fsec = selinux_file(file); 4026 isec = inode_security(file_inode(file)); 4027 /* 4028 * Save inode label and policy sequence number 4029 * at open-time so that selinux_file_permission 4030 * can determine whether revalidation is necessary. 4031 * Task label is already saved in the file security 4032 * struct as its SID. 4033 */ 4034 fsec->isid = isec->sid; 4035 fsec->pseqno = avc_policy_seqno(&selinux_state); 4036 /* 4037 * Since the inode label or policy seqno may have changed 4038 * between the selinux_inode_permission check and the saving 4039 * of state above, recheck that access is still permitted. 4040 * Otherwise, access might never be revalidated against the 4041 * new inode label or new policy. 4042 * This check is not redundant - do not remove. 4043 */ 4044 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 4045 } 4046 4047 /* task security operations */ 4048 4049 static int selinux_task_alloc(struct task_struct *task, 4050 unsigned long clone_flags) 4051 { 4052 u32 sid = current_sid(); 4053 4054 return avc_has_perm(&selinux_state, 4055 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 4056 } 4057 4058 /* 4059 * prepare a new set of credentials for modification 4060 */ 4061 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 4062 gfp_t gfp) 4063 { 4064 const struct task_security_struct *old_tsec = selinux_cred(old); 4065 struct task_security_struct *tsec = selinux_cred(new); 4066 4067 *tsec = *old_tsec; 4068 return 0; 4069 } 4070 4071 /* 4072 * transfer the SELinux data to a blank set of creds 4073 */ 4074 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 4075 { 4076 const struct task_security_struct *old_tsec = selinux_cred(old); 4077 struct task_security_struct *tsec = selinux_cred(new); 4078 4079 *tsec = *old_tsec; 4080 } 4081 4082 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 4083 { 4084 *secid = cred_sid(c); 4085 } 4086 4087 /* 4088 * set the security data for a kernel service 4089 * - all the creation contexts are set to unlabelled 4090 */ 4091 static int selinux_kernel_act_as(struct cred *new, u32 secid) 4092 { 4093 struct task_security_struct *tsec = selinux_cred(new); 4094 u32 sid = current_sid(); 4095 int ret; 4096 4097 ret = avc_has_perm(&selinux_state, 4098 sid, secid, 4099 SECCLASS_KERNEL_SERVICE, 4100 KERNEL_SERVICE__USE_AS_OVERRIDE, 4101 NULL); 4102 if (ret == 0) { 4103 tsec->sid = secid; 4104 tsec->create_sid = 0; 4105 tsec->keycreate_sid = 0; 4106 tsec->sockcreate_sid = 0; 4107 } 4108 return ret; 4109 } 4110 4111 /* 4112 * set the file creation context in a security record to the same as the 4113 * objective context of the specified inode 4114 */ 4115 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4116 { 4117 struct inode_security_struct *isec = inode_security(inode); 4118 struct task_security_struct *tsec = selinux_cred(new); 4119 u32 sid = current_sid(); 4120 int ret; 4121 4122 ret = avc_has_perm(&selinux_state, 4123 sid, isec->sid, 4124 SECCLASS_KERNEL_SERVICE, 4125 KERNEL_SERVICE__CREATE_FILES_AS, 4126 NULL); 4127 4128 if (ret == 0) 4129 tsec->create_sid = isec->sid; 4130 return ret; 4131 } 4132 4133 static int selinux_kernel_module_request(char *kmod_name) 4134 { 4135 struct common_audit_data ad; 4136 4137 ad.type = LSM_AUDIT_DATA_KMOD; 4138 ad.u.kmod_name = kmod_name; 4139 4140 return avc_has_perm(&selinux_state, 4141 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4142 SYSTEM__MODULE_REQUEST, &ad); 4143 } 4144 4145 static int selinux_kernel_module_from_file(struct file *file) 4146 { 4147 struct common_audit_data ad; 4148 struct inode_security_struct *isec; 4149 struct file_security_struct *fsec; 4150 u32 sid = current_sid(); 4151 int rc; 4152 4153 /* init_module */ 4154 if (file == NULL) 4155 return avc_has_perm(&selinux_state, 4156 sid, sid, SECCLASS_SYSTEM, 4157 SYSTEM__MODULE_LOAD, NULL); 4158 4159 /* finit_module */ 4160 4161 ad.type = LSM_AUDIT_DATA_FILE; 4162 ad.u.file = file; 4163 4164 fsec = selinux_file(file); 4165 if (sid != fsec->sid) { 4166 rc = avc_has_perm(&selinux_state, 4167 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4168 if (rc) 4169 return rc; 4170 } 4171 4172 isec = inode_security(file_inode(file)); 4173 return avc_has_perm(&selinux_state, 4174 sid, isec->sid, SECCLASS_SYSTEM, 4175 SYSTEM__MODULE_LOAD, &ad); 4176 } 4177 4178 static int selinux_kernel_read_file(struct file *file, 4179 enum kernel_read_file_id id, 4180 bool contents) 4181 { 4182 int rc = 0; 4183 4184 switch (id) { 4185 case READING_MODULE: 4186 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4187 break; 4188 default: 4189 break; 4190 } 4191 4192 return rc; 4193 } 4194 4195 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4196 { 4197 int rc = 0; 4198 4199 switch (id) { 4200 case LOADING_MODULE: 4201 rc = selinux_kernel_module_from_file(NULL); 4202 break; 4203 default: 4204 break; 4205 } 4206 4207 return rc; 4208 } 4209 4210 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4211 { 4212 return avc_has_perm(&selinux_state, 4213 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4214 PROCESS__SETPGID, NULL); 4215 } 4216 4217 static int selinux_task_getpgid(struct task_struct *p) 4218 { 4219 return avc_has_perm(&selinux_state, 4220 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4221 PROCESS__GETPGID, NULL); 4222 } 4223 4224 static int selinux_task_getsid(struct task_struct *p) 4225 { 4226 return avc_has_perm(&selinux_state, 4227 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4228 PROCESS__GETSESSION, NULL); 4229 } 4230 4231 static void selinux_task_getsecid_subj(struct task_struct *p, u32 *secid) 4232 { 4233 *secid = task_sid_subj(p); 4234 } 4235 4236 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) 4237 { 4238 *secid = task_sid_obj(p); 4239 } 4240 4241 static int selinux_task_setnice(struct task_struct *p, int nice) 4242 { 4243 return avc_has_perm(&selinux_state, 4244 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4245 PROCESS__SETSCHED, NULL); 4246 } 4247 4248 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4249 { 4250 return avc_has_perm(&selinux_state, 4251 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4252 PROCESS__SETSCHED, NULL); 4253 } 4254 4255 static int selinux_task_getioprio(struct task_struct *p) 4256 { 4257 return avc_has_perm(&selinux_state, 4258 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4259 PROCESS__GETSCHED, NULL); 4260 } 4261 4262 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4263 unsigned int flags) 4264 { 4265 u32 av = 0; 4266 4267 if (!flags) 4268 return 0; 4269 if (flags & LSM_PRLIMIT_WRITE) 4270 av |= PROCESS__SETRLIMIT; 4271 if (flags & LSM_PRLIMIT_READ) 4272 av |= PROCESS__GETRLIMIT; 4273 return avc_has_perm(&selinux_state, 4274 cred_sid(cred), cred_sid(tcred), 4275 SECCLASS_PROCESS, av, NULL); 4276 } 4277 4278 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4279 struct rlimit *new_rlim) 4280 { 4281 struct rlimit *old_rlim = p->signal->rlim + resource; 4282 4283 /* Control the ability to change the hard limit (whether 4284 lowering or raising it), so that the hard limit can 4285 later be used as a safe reset point for the soft limit 4286 upon context transitions. See selinux_bprm_committing_creds. */ 4287 if (old_rlim->rlim_max != new_rlim->rlim_max) 4288 return avc_has_perm(&selinux_state, 4289 current_sid(), task_sid_obj(p), 4290 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4291 4292 return 0; 4293 } 4294 4295 static int selinux_task_setscheduler(struct task_struct *p) 4296 { 4297 return avc_has_perm(&selinux_state, 4298 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4299 PROCESS__SETSCHED, NULL); 4300 } 4301 4302 static int selinux_task_getscheduler(struct task_struct *p) 4303 { 4304 return avc_has_perm(&selinux_state, 4305 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4306 PROCESS__GETSCHED, NULL); 4307 } 4308 4309 static int selinux_task_movememory(struct task_struct *p) 4310 { 4311 return avc_has_perm(&selinux_state, 4312 current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4313 PROCESS__SETSCHED, NULL); 4314 } 4315 4316 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4317 int sig, const struct cred *cred) 4318 { 4319 u32 secid; 4320 u32 perm; 4321 4322 if (!sig) 4323 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4324 else 4325 perm = signal_to_av(sig); 4326 if (!cred) 4327 secid = current_sid(); 4328 else 4329 secid = cred_sid(cred); 4330 return avc_has_perm(&selinux_state, 4331 secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4332 } 4333 4334 static void selinux_task_to_inode(struct task_struct *p, 4335 struct inode *inode) 4336 { 4337 struct inode_security_struct *isec = selinux_inode(inode); 4338 u32 sid = task_sid_obj(p); 4339 4340 spin_lock(&isec->lock); 4341 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4342 isec->sid = sid; 4343 isec->initialized = LABEL_INITIALIZED; 4344 spin_unlock(&isec->lock); 4345 } 4346 4347 /* Returns error only if unable to parse addresses */ 4348 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4349 struct common_audit_data *ad, u8 *proto) 4350 { 4351 int offset, ihlen, ret = -EINVAL; 4352 struct iphdr _iph, *ih; 4353 4354 offset = skb_network_offset(skb); 4355 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4356 if (ih == NULL) 4357 goto out; 4358 4359 ihlen = ih->ihl * 4; 4360 if (ihlen < sizeof(_iph)) 4361 goto out; 4362 4363 ad->u.net->v4info.saddr = ih->saddr; 4364 ad->u.net->v4info.daddr = ih->daddr; 4365 ret = 0; 4366 4367 if (proto) 4368 *proto = ih->protocol; 4369 4370 switch (ih->protocol) { 4371 case IPPROTO_TCP: { 4372 struct tcphdr _tcph, *th; 4373 4374 if (ntohs(ih->frag_off) & IP_OFFSET) 4375 break; 4376 4377 offset += ihlen; 4378 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4379 if (th == NULL) 4380 break; 4381 4382 ad->u.net->sport = th->source; 4383 ad->u.net->dport = th->dest; 4384 break; 4385 } 4386 4387 case IPPROTO_UDP: { 4388 struct udphdr _udph, *uh; 4389 4390 if (ntohs(ih->frag_off) & IP_OFFSET) 4391 break; 4392 4393 offset += ihlen; 4394 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4395 if (uh == NULL) 4396 break; 4397 4398 ad->u.net->sport = uh->source; 4399 ad->u.net->dport = uh->dest; 4400 break; 4401 } 4402 4403 case IPPROTO_DCCP: { 4404 struct dccp_hdr _dccph, *dh; 4405 4406 if (ntohs(ih->frag_off) & IP_OFFSET) 4407 break; 4408 4409 offset += ihlen; 4410 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4411 if (dh == NULL) 4412 break; 4413 4414 ad->u.net->sport = dh->dccph_sport; 4415 ad->u.net->dport = dh->dccph_dport; 4416 break; 4417 } 4418 4419 #if IS_ENABLED(CONFIG_IP_SCTP) 4420 case IPPROTO_SCTP: { 4421 struct sctphdr _sctph, *sh; 4422 4423 if (ntohs(ih->frag_off) & IP_OFFSET) 4424 break; 4425 4426 offset += ihlen; 4427 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4428 if (sh == NULL) 4429 break; 4430 4431 ad->u.net->sport = sh->source; 4432 ad->u.net->dport = sh->dest; 4433 break; 4434 } 4435 #endif 4436 default: 4437 break; 4438 } 4439 out: 4440 return ret; 4441 } 4442 4443 #if IS_ENABLED(CONFIG_IPV6) 4444 4445 /* Returns error only if unable to parse addresses */ 4446 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4447 struct common_audit_data *ad, u8 *proto) 4448 { 4449 u8 nexthdr; 4450 int ret = -EINVAL, offset; 4451 struct ipv6hdr _ipv6h, *ip6; 4452 __be16 frag_off; 4453 4454 offset = skb_network_offset(skb); 4455 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4456 if (ip6 == NULL) 4457 goto out; 4458 4459 ad->u.net->v6info.saddr = ip6->saddr; 4460 ad->u.net->v6info.daddr = ip6->daddr; 4461 ret = 0; 4462 4463 nexthdr = ip6->nexthdr; 4464 offset += sizeof(_ipv6h); 4465 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4466 if (offset < 0) 4467 goto out; 4468 4469 if (proto) 4470 *proto = nexthdr; 4471 4472 switch (nexthdr) { 4473 case IPPROTO_TCP: { 4474 struct tcphdr _tcph, *th; 4475 4476 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4477 if (th == NULL) 4478 break; 4479 4480 ad->u.net->sport = th->source; 4481 ad->u.net->dport = th->dest; 4482 break; 4483 } 4484 4485 case IPPROTO_UDP: { 4486 struct udphdr _udph, *uh; 4487 4488 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4489 if (uh == NULL) 4490 break; 4491 4492 ad->u.net->sport = uh->source; 4493 ad->u.net->dport = uh->dest; 4494 break; 4495 } 4496 4497 case IPPROTO_DCCP: { 4498 struct dccp_hdr _dccph, *dh; 4499 4500 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4501 if (dh == NULL) 4502 break; 4503 4504 ad->u.net->sport = dh->dccph_sport; 4505 ad->u.net->dport = dh->dccph_dport; 4506 break; 4507 } 4508 4509 #if IS_ENABLED(CONFIG_IP_SCTP) 4510 case IPPROTO_SCTP: { 4511 struct sctphdr _sctph, *sh; 4512 4513 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4514 if (sh == NULL) 4515 break; 4516 4517 ad->u.net->sport = sh->source; 4518 ad->u.net->dport = sh->dest; 4519 break; 4520 } 4521 #endif 4522 /* includes fragments */ 4523 default: 4524 break; 4525 } 4526 out: 4527 return ret; 4528 } 4529 4530 #endif /* IPV6 */ 4531 4532 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4533 char **_addrp, int src, u8 *proto) 4534 { 4535 char *addrp; 4536 int ret; 4537 4538 switch (ad->u.net->family) { 4539 case PF_INET: 4540 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4541 if (ret) 4542 goto parse_error; 4543 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4544 &ad->u.net->v4info.daddr); 4545 goto okay; 4546 4547 #if IS_ENABLED(CONFIG_IPV6) 4548 case PF_INET6: 4549 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4550 if (ret) 4551 goto parse_error; 4552 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4553 &ad->u.net->v6info.daddr); 4554 goto okay; 4555 #endif /* IPV6 */ 4556 default: 4557 addrp = NULL; 4558 goto okay; 4559 } 4560 4561 parse_error: 4562 pr_warn( 4563 "SELinux: failure in selinux_parse_skb()," 4564 " unable to parse packet\n"); 4565 return ret; 4566 4567 okay: 4568 if (_addrp) 4569 *_addrp = addrp; 4570 return 0; 4571 } 4572 4573 /** 4574 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4575 * @skb: the packet 4576 * @family: protocol family 4577 * @sid: the packet's peer label SID 4578 * 4579 * Description: 4580 * Check the various different forms of network peer labeling and determine 4581 * the peer label/SID for the packet; most of the magic actually occurs in 4582 * the security server function security_net_peersid_cmp(). The function 4583 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4584 * or -EACCES if @sid is invalid due to inconsistencies with the different 4585 * peer labels. 4586 * 4587 */ 4588 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4589 { 4590 int err; 4591 u32 xfrm_sid; 4592 u32 nlbl_sid; 4593 u32 nlbl_type; 4594 4595 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4596 if (unlikely(err)) 4597 return -EACCES; 4598 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4599 if (unlikely(err)) 4600 return -EACCES; 4601 4602 err = security_net_peersid_resolve(&selinux_state, nlbl_sid, 4603 nlbl_type, xfrm_sid, sid); 4604 if (unlikely(err)) { 4605 pr_warn( 4606 "SELinux: failure in selinux_skb_peerlbl_sid()," 4607 " unable to determine packet's peer label\n"); 4608 return -EACCES; 4609 } 4610 4611 return 0; 4612 } 4613 4614 /** 4615 * selinux_conn_sid - Determine the child socket label for a connection 4616 * @sk_sid: the parent socket's SID 4617 * @skb_sid: the packet's SID 4618 * @conn_sid: the resulting connection SID 4619 * 4620 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4621 * combined with the MLS information from @skb_sid in order to create 4622 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4623 * of @sk_sid. Returns zero on success, negative values on failure. 4624 * 4625 */ 4626 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4627 { 4628 int err = 0; 4629 4630 if (skb_sid != SECSID_NULL) 4631 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid, 4632 conn_sid); 4633 else 4634 *conn_sid = sk_sid; 4635 4636 return err; 4637 } 4638 4639 /* socket security operations */ 4640 4641 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4642 u16 secclass, u32 *socksid) 4643 { 4644 if (tsec->sockcreate_sid > SECSID_NULL) { 4645 *socksid = tsec->sockcreate_sid; 4646 return 0; 4647 } 4648 4649 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid, 4650 secclass, NULL, socksid); 4651 } 4652 4653 static int sock_has_perm(struct sock *sk, u32 perms) 4654 { 4655 struct sk_security_struct *sksec = sk->sk_security; 4656 struct common_audit_data ad; 4657 struct lsm_network_audit net = {0,}; 4658 4659 if (sksec->sid == SECINITSID_KERNEL) 4660 return 0; 4661 4662 ad.type = LSM_AUDIT_DATA_NET; 4663 ad.u.net = &net; 4664 ad.u.net->sk = sk; 4665 4666 return avc_has_perm(&selinux_state, 4667 current_sid(), sksec->sid, sksec->sclass, perms, 4668 &ad); 4669 } 4670 4671 static int selinux_socket_create(int family, int type, 4672 int protocol, int kern) 4673 { 4674 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4675 u32 newsid; 4676 u16 secclass; 4677 int rc; 4678 4679 if (kern) 4680 return 0; 4681 4682 secclass = socket_type_to_security_class(family, type, protocol); 4683 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4684 if (rc) 4685 return rc; 4686 4687 return avc_has_perm(&selinux_state, 4688 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4689 } 4690 4691 static int selinux_socket_post_create(struct socket *sock, int family, 4692 int type, int protocol, int kern) 4693 { 4694 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4695 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4696 struct sk_security_struct *sksec; 4697 u16 sclass = socket_type_to_security_class(family, type, protocol); 4698 u32 sid = SECINITSID_KERNEL; 4699 int err = 0; 4700 4701 if (!kern) { 4702 err = socket_sockcreate_sid(tsec, sclass, &sid); 4703 if (err) 4704 return err; 4705 } 4706 4707 isec->sclass = sclass; 4708 isec->sid = sid; 4709 isec->initialized = LABEL_INITIALIZED; 4710 4711 if (sock->sk) { 4712 sksec = sock->sk->sk_security; 4713 sksec->sclass = sclass; 4714 sksec->sid = sid; 4715 /* Allows detection of the first association on this socket */ 4716 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4717 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4718 4719 err = selinux_netlbl_socket_post_create(sock->sk, family); 4720 } 4721 4722 return err; 4723 } 4724 4725 static int selinux_socket_socketpair(struct socket *socka, 4726 struct socket *sockb) 4727 { 4728 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4729 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4730 4731 sksec_a->peer_sid = sksec_b->sid; 4732 sksec_b->peer_sid = sksec_a->sid; 4733 4734 return 0; 4735 } 4736 4737 /* Range of port numbers used to automatically bind. 4738 Need to determine whether we should perform a name_bind 4739 permission check between the socket and the port number. */ 4740 4741 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4742 { 4743 struct sock *sk = sock->sk; 4744 struct sk_security_struct *sksec = sk->sk_security; 4745 u16 family; 4746 int err; 4747 4748 err = sock_has_perm(sk, SOCKET__BIND); 4749 if (err) 4750 goto out; 4751 4752 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4753 family = sk->sk_family; 4754 if (family == PF_INET || family == PF_INET6) { 4755 char *addrp; 4756 struct common_audit_data ad; 4757 struct lsm_network_audit net = {0,}; 4758 struct sockaddr_in *addr4 = NULL; 4759 struct sockaddr_in6 *addr6 = NULL; 4760 u16 family_sa; 4761 unsigned short snum; 4762 u32 sid, node_perm; 4763 4764 /* 4765 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4766 * that validates multiple binding addresses. Because of this 4767 * need to check address->sa_family as it is possible to have 4768 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4769 */ 4770 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4771 return -EINVAL; 4772 family_sa = address->sa_family; 4773 switch (family_sa) { 4774 case AF_UNSPEC: 4775 case AF_INET: 4776 if (addrlen < sizeof(struct sockaddr_in)) 4777 return -EINVAL; 4778 addr4 = (struct sockaddr_in *)address; 4779 if (family_sa == AF_UNSPEC) { 4780 /* see __inet_bind(), we only want to allow 4781 * AF_UNSPEC if the address is INADDR_ANY 4782 */ 4783 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4784 goto err_af; 4785 family_sa = AF_INET; 4786 } 4787 snum = ntohs(addr4->sin_port); 4788 addrp = (char *)&addr4->sin_addr.s_addr; 4789 break; 4790 case AF_INET6: 4791 if (addrlen < SIN6_LEN_RFC2133) 4792 return -EINVAL; 4793 addr6 = (struct sockaddr_in6 *)address; 4794 snum = ntohs(addr6->sin6_port); 4795 addrp = (char *)&addr6->sin6_addr.s6_addr; 4796 break; 4797 default: 4798 goto err_af; 4799 } 4800 4801 ad.type = LSM_AUDIT_DATA_NET; 4802 ad.u.net = &net; 4803 ad.u.net->sport = htons(snum); 4804 ad.u.net->family = family_sa; 4805 4806 if (snum) { 4807 int low, high; 4808 4809 inet_get_local_port_range(sock_net(sk), &low, &high); 4810 4811 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4812 snum < low || snum > high) { 4813 err = sel_netport_sid(sk->sk_protocol, 4814 snum, &sid); 4815 if (err) 4816 goto out; 4817 err = avc_has_perm(&selinux_state, 4818 sksec->sid, sid, 4819 sksec->sclass, 4820 SOCKET__NAME_BIND, &ad); 4821 if (err) 4822 goto out; 4823 } 4824 } 4825 4826 switch (sksec->sclass) { 4827 case SECCLASS_TCP_SOCKET: 4828 node_perm = TCP_SOCKET__NODE_BIND; 4829 break; 4830 4831 case SECCLASS_UDP_SOCKET: 4832 node_perm = UDP_SOCKET__NODE_BIND; 4833 break; 4834 4835 case SECCLASS_DCCP_SOCKET: 4836 node_perm = DCCP_SOCKET__NODE_BIND; 4837 break; 4838 4839 case SECCLASS_SCTP_SOCKET: 4840 node_perm = SCTP_SOCKET__NODE_BIND; 4841 break; 4842 4843 default: 4844 node_perm = RAWIP_SOCKET__NODE_BIND; 4845 break; 4846 } 4847 4848 err = sel_netnode_sid(addrp, family_sa, &sid); 4849 if (err) 4850 goto out; 4851 4852 if (family_sa == AF_INET) 4853 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4854 else 4855 ad.u.net->v6info.saddr = addr6->sin6_addr; 4856 4857 err = avc_has_perm(&selinux_state, 4858 sksec->sid, sid, 4859 sksec->sclass, node_perm, &ad); 4860 if (err) 4861 goto out; 4862 } 4863 out: 4864 return err; 4865 err_af: 4866 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4867 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4868 return -EINVAL; 4869 return -EAFNOSUPPORT; 4870 } 4871 4872 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4873 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4874 */ 4875 static int selinux_socket_connect_helper(struct socket *sock, 4876 struct sockaddr *address, int addrlen) 4877 { 4878 struct sock *sk = sock->sk; 4879 struct sk_security_struct *sksec = sk->sk_security; 4880 int err; 4881 4882 err = sock_has_perm(sk, SOCKET__CONNECT); 4883 if (err) 4884 return err; 4885 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4886 return -EINVAL; 4887 4888 /* connect(AF_UNSPEC) has special handling, as it is a documented 4889 * way to disconnect the socket 4890 */ 4891 if (address->sa_family == AF_UNSPEC) 4892 return 0; 4893 4894 /* 4895 * If a TCP, DCCP or SCTP socket, check name_connect permission 4896 * for the port. 4897 */ 4898 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4899 sksec->sclass == SECCLASS_DCCP_SOCKET || 4900 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4901 struct common_audit_data ad; 4902 struct lsm_network_audit net = {0,}; 4903 struct sockaddr_in *addr4 = NULL; 4904 struct sockaddr_in6 *addr6 = NULL; 4905 unsigned short snum; 4906 u32 sid, perm; 4907 4908 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4909 * that validates multiple connect addresses. Because of this 4910 * need to check address->sa_family as it is possible to have 4911 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4912 */ 4913 switch (address->sa_family) { 4914 case AF_INET: 4915 addr4 = (struct sockaddr_in *)address; 4916 if (addrlen < sizeof(struct sockaddr_in)) 4917 return -EINVAL; 4918 snum = ntohs(addr4->sin_port); 4919 break; 4920 case AF_INET6: 4921 addr6 = (struct sockaddr_in6 *)address; 4922 if (addrlen < SIN6_LEN_RFC2133) 4923 return -EINVAL; 4924 snum = ntohs(addr6->sin6_port); 4925 break; 4926 default: 4927 /* Note that SCTP services expect -EINVAL, whereas 4928 * others expect -EAFNOSUPPORT. 4929 */ 4930 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4931 return -EINVAL; 4932 else 4933 return -EAFNOSUPPORT; 4934 } 4935 4936 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4937 if (err) 4938 return err; 4939 4940 switch (sksec->sclass) { 4941 case SECCLASS_TCP_SOCKET: 4942 perm = TCP_SOCKET__NAME_CONNECT; 4943 break; 4944 case SECCLASS_DCCP_SOCKET: 4945 perm = DCCP_SOCKET__NAME_CONNECT; 4946 break; 4947 case SECCLASS_SCTP_SOCKET: 4948 perm = SCTP_SOCKET__NAME_CONNECT; 4949 break; 4950 } 4951 4952 ad.type = LSM_AUDIT_DATA_NET; 4953 ad.u.net = &net; 4954 ad.u.net->dport = htons(snum); 4955 ad.u.net->family = address->sa_family; 4956 err = avc_has_perm(&selinux_state, 4957 sksec->sid, sid, sksec->sclass, perm, &ad); 4958 if (err) 4959 return err; 4960 } 4961 4962 return 0; 4963 } 4964 4965 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4966 static int selinux_socket_connect(struct socket *sock, 4967 struct sockaddr *address, int addrlen) 4968 { 4969 int err; 4970 struct sock *sk = sock->sk; 4971 4972 err = selinux_socket_connect_helper(sock, address, addrlen); 4973 if (err) 4974 return err; 4975 4976 return selinux_netlbl_socket_connect(sk, address); 4977 } 4978 4979 static int selinux_socket_listen(struct socket *sock, int backlog) 4980 { 4981 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4982 } 4983 4984 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4985 { 4986 int err; 4987 struct inode_security_struct *isec; 4988 struct inode_security_struct *newisec; 4989 u16 sclass; 4990 u32 sid; 4991 4992 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4993 if (err) 4994 return err; 4995 4996 isec = inode_security_novalidate(SOCK_INODE(sock)); 4997 spin_lock(&isec->lock); 4998 sclass = isec->sclass; 4999 sid = isec->sid; 5000 spin_unlock(&isec->lock); 5001 5002 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 5003 newisec->sclass = sclass; 5004 newisec->sid = sid; 5005 newisec->initialized = LABEL_INITIALIZED; 5006 5007 return 0; 5008 } 5009 5010 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 5011 int size) 5012 { 5013 return sock_has_perm(sock->sk, SOCKET__WRITE); 5014 } 5015 5016 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 5017 int size, int flags) 5018 { 5019 return sock_has_perm(sock->sk, SOCKET__READ); 5020 } 5021 5022 static int selinux_socket_getsockname(struct socket *sock) 5023 { 5024 return sock_has_perm(sock->sk, SOCKET__GETATTR); 5025 } 5026 5027 static int selinux_socket_getpeername(struct socket *sock) 5028 { 5029 return sock_has_perm(sock->sk, SOCKET__GETATTR); 5030 } 5031 5032 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 5033 { 5034 int err; 5035 5036 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 5037 if (err) 5038 return err; 5039 5040 return selinux_netlbl_socket_setsockopt(sock, level, optname); 5041 } 5042 5043 static int selinux_socket_getsockopt(struct socket *sock, int level, 5044 int optname) 5045 { 5046 return sock_has_perm(sock->sk, SOCKET__GETOPT); 5047 } 5048 5049 static int selinux_socket_shutdown(struct socket *sock, int how) 5050 { 5051 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 5052 } 5053 5054 static int selinux_socket_unix_stream_connect(struct sock *sock, 5055 struct sock *other, 5056 struct sock *newsk) 5057 { 5058 struct sk_security_struct *sksec_sock = sock->sk_security; 5059 struct sk_security_struct *sksec_other = other->sk_security; 5060 struct sk_security_struct *sksec_new = newsk->sk_security; 5061 struct common_audit_data ad; 5062 struct lsm_network_audit net = {0,}; 5063 int err; 5064 5065 ad.type = LSM_AUDIT_DATA_NET; 5066 ad.u.net = &net; 5067 ad.u.net->sk = other; 5068 5069 err = avc_has_perm(&selinux_state, 5070 sksec_sock->sid, sksec_other->sid, 5071 sksec_other->sclass, 5072 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 5073 if (err) 5074 return err; 5075 5076 /* server child socket */ 5077 sksec_new->peer_sid = sksec_sock->sid; 5078 err = security_sid_mls_copy(&selinux_state, sksec_other->sid, 5079 sksec_sock->sid, &sksec_new->sid); 5080 if (err) 5081 return err; 5082 5083 /* connecting socket */ 5084 sksec_sock->peer_sid = sksec_new->sid; 5085 5086 return 0; 5087 } 5088 5089 static int selinux_socket_unix_may_send(struct socket *sock, 5090 struct socket *other) 5091 { 5092 struct sk_security_struct *ssec = sock->sk->sk_security; 5093 struct sk_security_struct *osec = other->sk->sk_security; 5094 struct common_audit_data ad; 5095 struct lsm_network_audit net = {0,}; 5096 5097 ad.type = LSM_AUDIT_DATA_NET; 5098 ad.u.net = &net; 5099 ad.u.net->sk = other->sk; 5100 5101 return avc_has_perm(&selinux_state, 5102 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 5103 &ad); 5104 } 5105 5106 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 5107 char *addrp, u16 family, u32 peer_sid, 5108 struct common_audit_data *ad) 5109 { 5110 int err; 5111 u32 if_sid; 5112 u32 node_sid; 5113 5114 err = sel_netif_sid(ns, ifindex, &if_sid); 5115 if (err) 5116 return err; 5117 err = avc_has_perm(&selinux_state, 5118 peer_sid, if_sid, 5119 SECCLASS_NETIF, NETIF__INGRESS, ad); 5120 if (err) 5121 return err; 5122 5123 err = sel_netnode_sid(addrp, family, &node_sid); 5124 if (err) 5125 return err; 5126 return avc_has_perm(&selinux_state, 5127 peer_sid, node_sid, 5128 SECCLASS_NODE, NODE__RECVFROM, ad); 5129 } 5130 5131 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5132 u16 family) 5133 { 5134 int err = 0; 5135 struct sk_security_struct *sksec = sk->sk_security; 5136 u32 sk_sid = sksec->sid; 5137 struct common_audit_data ad; 5138 struct lsm_network_audit net = {0,}; 5139 char *addrp; 5140 5141 ad.type = LSM_AUDIT_DATA_NET; 5142 ad.u.net = &net; 5143 ad.u.net->netif = skb->skb_iif; 5144 ad.u.net->family = family; 5145 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5146 if (err) 5147 return err; 5148 5149 if (selinux_secmark_enabled()) { 5150 err = avc_has_perm(&selinux_state, 5151 sk_sid, skb->secmark, SECCLASS_PACKET, 5152 PACKET__RECV, &ad); 5153 if (err) 5154 return err; 5155 } 5156 5157 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5158 if (err) 5159 return err; 5160 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5161 5162 return err; 5163 } 5164 5165 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5166 { 5167 int err; 5168 struct sk_security_struct *sksec = sk->sk_security; 5169 u16 family = sk->sk_family; 5170 u32 sk_sid = sksec->sid; 5171 struct common_audit_data ad; 5172 struct lsm_network_audit net = {0,}; 5173 char *addrp; 5174 u8 secmark_active; 5175 u8 peerlbl_active; 5176 5177 if (family != PF_INET && family != PF_INET6) 5178 return 0; 5179 5180 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5181 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5182 family = PF_INET; 5183 5184 /* If any sort of compatibility mode is enabled then handoff processing 5185 * to the selinux_sock_rcv_skb_compat() function to deal with the 5186 * special handling. We do this in an attempt to keep this function 5187 * as fast and as clean as possible. */ 5188 if (!selinux_policycap_netpeer()) 5189 return selinux_sock_rcv_skb_compat(sk, skb, family); 5190 5191 secmark_active = selinux_secmark_enabled(); 5192 peerlbl_active = selinux_peerlbl_enabled(); 5193 if (!secmark_active && !peerlbl_active) 5194 return 0; 5195 5196 ad.type = LSM_AUDIT_DATA_NET; 5197 ad.u.net = &net; 5198 ad.u.net->netif = skb->skb_iif; 5199 ad.u.net->family = family; 5200 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5201 if (err) 5202 return err; 5203 5204 if (peerlbl_active) { 5205 u32 peer_sid; 5206 5207 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5208 if (err) 5209 return err; 5210 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5211 addrp, family, peer_sid, &ad); 5212 if (err) { 5213 selinux_netlbl_err(skb, family, err, 0); 5214 return err; 5215 } 5216 err = avc_has_perm(&selinux_state, 5217 sk_sid, peer_sid, SECCLASS_PEER, 5218 PEER__RECV, &ad); 5219 if (err) { 5220 selinux_netlbl_err(skb, family, err, 0); 5221 return err; 5222 } 5223 } 5224 5225 if (secmark_active) { 5226 err = avc_has_perm(&selinux_state, 5227 sk_sid, skb->secmark, SECCLASS_PACKET, 5228 PACKET__RECV, &ad); 5229 if (err) 5230 return err; 5231 } 5232 5233 return err; 5234 } 5235 5236 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 5237 int __user *optlen, unsigned len) 5238 { 5239 int err = 0; 5240 char *scontext; 5241 u32 scontext_len; 5242 struct sk_security_struct *sksec = sock->sk->sk_security; 5243 u32 peer_sid = SECSID_NULL; 5244 5245 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5246 sksec->sclass == SECCLASS_TCP_SOCKET || 5247 sksec->sclass == SECCLASS_SCTP_SOCKET) 5248 peer_sid = sksec->peer_sid; 5249 if (peer_sid == SECSID_NULL) 5250 return -ENOPROTOOPT; 5251 5252 err = security_sid_to_context(&selinux_state, peer_sid, &scontext, 5253 &scontext_len); 5254 if (err) 5255 return err; 5256 5257 if (scontext_len > len) { 5258 err = -ERANGE; 5259 goto out_len; 5260 } 5261 5262 if (copy_to_user(optval, scontext, scontext_len)) 5263 err = -EFAULT; 5264 5265 out_len: 5266 if (put_user(scontext_len, optlen)) 5267 err = -EFAULT; 5268 kfree(scontext); 5269 return err; 5270 } 5271 5272 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5273 { 5274 u32 peer_secid = SECSID_NULL; 5275 u16 family; 5276 struct inode_security_struct *isec; 5277 5278 if (skb && skb->protocol == htons(ETH_P_IP)) 5279 family = PF_INET; 5280 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5281 family = PF_INET6; 5282 else if (sock) 5283 family = sock->sk->sk_family; 5284 else 5285 goto out; 5286 5287 if (sock && family == PF_UNIX) { 5288 isec = inode_security_novalidate(SOCK_INODE(sock)); 5289 peer_secid = isec->sid; 5290 } else if (skb) 5291 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5292 5293 out: 5294 *secid = peer_secid; 5295 if (peer_secid == SECSID_NULL) 5296 return -EINVAL; 5297 return 0; 5298 } 5299 5300 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5301 { 5302 struct sk_security_struct *sksec; 5303 5304 sksec = kzalloc(sizeof(*sksec), priority); 5305 if (!sksec) 5306 return -ENOMEM; 5307 5308 sksec->peer_sid = SECINITSID_UNLABELED; 5309 sksec->sid = SECINITSID_UNLABELED; 5310 sksec->sclass = SECCLASS_SOCKET; 5311 selinux_netlbl_sk_security_reset(sksec); 5312 sk->sk_security = sksec; 5313 5314 return 0; 5315 } 5316 5317 static void selinux_sk_free_security(struct sock *sk) 5318 { 5319 struct sk_security_struct *sksec = sk->sk_security; 5320 5321 sk->sk_security = NULL; 5322 selinux_netlbl_sk_security_free(sksec); 5323 kfree(sksec); 5324 } 5325 5326 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5327 { 5328 struct sk_security_struct *sksec = sk->sk_security; 5329 struct sk_security_struct *newsksec = newsk->sk_security; 5330 5331 newsksec->sid = sksec->sid; 5332 newsksec->peer_sid = sksec->peer_sid; 5333 newsksec->sclass = sksec->sclass; 5334 5335 selinux_netlbl_sk_security_reset(newsksec); 5336 } 5337 5338 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 5339 { 5340 if (!sk) 5341 *secid = SECINITSID_ANY_SOCKET; 5342 else { 5343 struct sk_security_struct *sksec = sk->sk_security; 5344 5345 *secid = sksec->sid; 5346 } 5347 } 5348 5349 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5350 { 5351 struct inode_security_struct *isec = 5352 inode_security_novalidate(SOCK_INODE(parent)); 5353 struct sk_security_struct *sksec = sk->sk_security; 5354 5355 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5356 sk->sk_family == PF_UNIX) 5357 isec->sid = sksec->sid; 5358 sksec->sclass = isec->sclass; 5359 } 5360 5361 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming 5362 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association 5363 * already present). 5364 */ 5365 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep, 5366 struct sk_buff *skb) 5367 { 5368 struct sk_security_struct *sksec = ep->base.sk->sk_security; 5369 struct common_audit_data ad; 5370 struct lsm_network_audit net = {0,}; 5371 u8 peerlbl_active; 5372 u32 peer_sid = SECINITSID_UNLABELED; 5373 u32 conn_sid; 5374 int err = 0; 5375 5376 if (!selinux_policycap_extsockclass()) 5377 return 0; 5378 5379 peerlbl_active = selinux_peerlbl_enabled(); 5380 5381 if (peerlbl_active) { 5382 /* This will return peer_sid = SECSID_NULL if there are 5383 * no peer labels, see security_net_peersid_resolve(). 5384 */ 5385 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family, 5386 &peer_sid); 5387 if (err) 5388 return err; 5389 5390 if (peer_sid == SECSID_NULL) 5391 peer_sid = SECINITSID_UNLABELED; 5392 } 5393 5394 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5395 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5396 5397 /* Here as first association on socket. As the peer SID 5398 * was allowed by peer recv (and the netif/node checks), 5399 * then it is approved by policy and used as the primary 5400 * peer SID for getpeercon(3). 5401 */ 5402 sksec->peer_sid = peer_sid; 5403 } else if (sksec->peer_sid != peer_sid) { 5404 /* Other association peer SIDs are checked to enforce 5405 * consistency among the peer SIDs. 5406 */ 5407 ad.type = LSM_AUDIT_DATA_NET; 5408 ad.u.net = &net; 5409 ad.u.net->sk = ep->base.sk; 5410 err = avc_has_perm(&selinux_state, 5411 sksec->peer_sid, peer_sid, sksec->sclass, 5412 SCTP_SOCKET__ASSOCIATION, &ad); 5413 if (err) 5414 return err; 5415 } 5416 5417 /* Compute the MLS component for the connection and store 5418 * the information in ep. This will be used by SCTP TCP type 5419 * sockets and peeled off connections as they cause a new 5420 * socket to be generated. selinux_sctp_sk_clone() will then 5421 * plug this into the new socket. 5422 */ 5423 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid); 5424 if (err) 5425 return err; 5426 5427 ep->secid = conn_sid; 5428 ep->peer_secid = peer_sid; 5429 5430 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5431 return selinux_netlbl_sctp_assoc_request(ep, skb); 5432 } 5433 5434 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5435 * based on their @optname. 5436 */ 5437 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5438 struct sockaddr *address, 5439 int addrlen) 5440 { 5441 int len, err = 0, walk_size = 0; 5442 void *addr_buf; 5443 struct sockaddr *addr; 5444 struct socket *sock; 5445 5446 if (!selinux_policycap_extsockclass()) 5447 return 0; 5448 5449 /* Process one or more addresses that may be IPv4 or IPv6 */ 5450 sock = sk->sk_socket; 5451 addr_buf = address; 5452 5453 while (walk_size < addrlen) { 5454 if (walk_size + sizeof(sa_family_t) > addrlen) 5455 return -EINVAL; 5456 5457 addr = addr_buf; 5458 switch (addr->sa_family) { 5459 case AF_UNSPEC: 5460 case AF_INET: 5461 len = sizeof(struct sockaddr_in); 5462 break; 5463 case AF_INET6: 5464 len = sizeof(struct sockaddr_in6); 5465 break; 5466 default: 5467 return -EINVAL; 5468 } 5469 5470 if (walk_size + len > addrlen) 5471 return -EINVAL; 5472 5473 err = -EINVAL; 5474 switch (optname) { 5475 /* Bind checks */ 5476 case SCTP_PRIMARY_ADDR: 5477 case SCTP_SET_PEER_PRIMARY_ADDR: 5478 case SCTP_SOCKOPT_BINDX_ADD: 5479 err = selinux_socket_bind(sock, addr, len); 5480 break; 5481 /* Connect checks */ 5482 case SCTP_SOCKOPT_CONNECTX: 5483 case SCTP_PARAM_SET_PRIMARY: 5484 case SCTP_PARAM_ADD_IP: 5485 case SCTP_SENDMSG_CONNECT: 5486 err = selinux_socket_connect_helper(sock, addr, len); 5487 if (err) 5488 return err; 5489 5490 /* As selinux_sctp_bind_connect() is called by the 5491 * SCTP protocol layer, the socket is already locked, 5492 * therefore selinux_netlbl_socket_connect_locked() 5493 * is called here. The situations handled are: 5494 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5495 * whenever a new IP address is added or when a new 5496 * primary address is selected. 5497 * Note that an SCTP connect(2) call happens before 5498 * the SCTP protocol layer and is handled via 5499 * selinux_socket_connect(). 5500 */ 5501 err = selinux_netlbl_socket_connect_locked(sk, addr); 5502 break; 5503 } 5504 5505 if (err) 5506 return err; 5507 5508 addr_buf += len; 5509 walk_size += len; 5510 } 5511 5512 return 0; 5513 } 5514 5515 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5516 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk, 5517 struct sock *newsk) 5518 { 5519 struct sk_security_struct *sksec = sk->sk_security; 5520 struct sk_security_struct *newsksec = newsk->sk_security; 5521 5522 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5523 * the non-sctp clone version. 5524 */ 5525 if (!selinux_policycap_extsockclass()) 5526 return selinux_sk_clone_security(sk, newsk); 5527 5528 newsksec->sid = ep->secid; 5529 newsksec->peer_sid = ep->peer_secid; 5530 newsksec->sclass = sksec->sclass; 5531 selinux_netlbl_sctp_sk_clone(sk, newsk); 5532 } 5533 5534 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5535 struct request_sock *req) 5536 { 5537 struct sk_security_struct *sksec = sk->sk_security; 5538 int err; 5539 u16 family = req->rsk_ops->family; 5540 u32 connsid; 5541 u32 peersid; 5542 5543 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5544 if (err) 5545 return err; 5546 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5547 if (err) 5548 return err; 5549 req->secid = connsid; 5550 req->peer_secid = peersid; 5551 5552 return selinux_netlbl_inet_conn_request(req, family); 5553 } 5554 5555 static void selinux_inet_csk_clone(struct sock *newsk, 5556 const struct request_sock *req) 5557 { 5558 struct sk_security_struct *newsksec = newsk->sk_security; 5559 5560 newsksec->sid = req->secid; 5561 newsksec->peer_sid = req->peer_secid; 5562 /* NOTE: Ideally, we should also get the isec->sid for the 5563 new socket in sync, but we don't have the isec available yet. 5564 So we will wait until sock_graft to do it, by which 5565 time it will have been created and available. */ 5566 5567 /* We don't need to take any sort of lock here as we are the only 5568 * thread with access to newsksec */ 5569 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5570 } 5571 5572 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5573 { 5574 u16 family = sk->sk_family; 5575 struct sk_security_struct *sksec = sk->sk_security; 5576 5577 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5578 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5579 family = PF_INET; 5580 5581 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5582 } 5583 5584 static int selinux_secmark_relabel_packet(u32 sid) 5585 { 5586 const struct task_security_struct *__tsec; 5587 u32 tsid; 5588 5589 __tsec = selinux_cred(current_cred()); 5590 tsid = __tsec->sid; 5591 5592 return avc_has_perm(&selinux_state, 5593 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5594 NULL); 5595 } 5596 5597 static void selinux_secmark_refcount_inc(void) 5598 { 5599 atomic_inc(&selinux_secmark_refcount); 5600 } 5601 5602 static void selinux_secmark_refcount_dec(void) 5603 { 5604 atomic_dec(&selinux_secmark_refcount); 5605 } 5606 5607 static void selinux_req_classify_flow(const struct request_sock *req, 5608 struct flowi_common *flic) 5609 { 5610 flic->flowic_secid = req->secid; 5611 } 5612 5613 static int selinux_tun_dev_alloc_security(void **security) 5614 { 5615 struct tun_security_struct *tunsec; 5616 5617 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5618 if (!tunsec) 5619 return -ENOMEM; 5620 tunsec->sid = current_sid(); 5621 5622 *security = tunsec; 5623 return 0; 5624 } 5625 5626 static void selinux_tun_dev_free_security(void *security) 5627 { 5628 kfree(security); 5629 } 5630 5631 static int selinux_tun_dev_create(void) 5632 { 5633 u32 sid = current_sid(); 5634 5635 /* we aren't taking into account the "sockcreate" SID since the socket 5636 * that is being created here is not a socket in the traditional sense, 5637 * instead it is a private sock, accessible only to the kernel, and 5638 * representing a wide range of network traffic spanning multiple 5639 * connections unlike traditional sockets - check the TUN driver to 5640 * get a better understanding of why this socket is special */ 5641 5642 return avc_has_perm(&selinux_state, 5643 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5644 NULL); 5645 } 5646 5647 static int selinux_tun_dev_attach_queue(void *security) 5648 { 5649 struct tun_security_struct *tunsec = security; 5650 5651 return avc_has_perm(&selinux_state, 5652 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5653 TUN_SOCKET__ATTACH_QUEUE, NULL); 5654 } 5655 5656 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5657 { 5658 struct tun_security_struct *tunsec = security; 5659 struct sk_security_struct *sksec = sk->sk_security; 5660 5661 /* we don't currently perform any NetLabel based labeling here and it 5662 * isn't clear that we would want to do so anyway; while we could apply 5663 * labeling without the support of the TUN user the resulting labeled 5664 * traffic from the other end of the connection would almost certainly 5665 * cause confusion to the TUN user that had no idea network labeling 5666 * protocols were being used */ 5667 5668 sksec->sid = tunsec->sid; 5669 sksec->sclass = SECCLASS_TUN_SOCKET; 5670 5671 return 0; 5672 } 5673 5674 static int selinux_tun_dev_open(void *security) 5675 { 5676 struct tun_security_struct *tunsec = security; 5677 u32 sid = current_sid(); 5678 int err; 5679 5680 err = avc_has_perm(&selinux_state, 5681 sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5682 TUN_SOCKET__RELABELFROM, NULL); 5683 if (err) 5684 return err; 5685 err = avc_has_perm(&selinux_state, 5686 sid, sid, SECCLASS_TUN_SOCKET, 5687 TUN_SOCKET__RELABELTO, NULL); 5688 if (err) 5689 return err; 5690 tunsec->sid = sid; 5691 5692 return 0; 5693 } 5694 5695 #ifdef CONFIG_NETFILTER 5696 5697 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5698 const struct net_device *indev, 5699 u16 family) 5700 { 5701 int err; 5702 char *addrp; 5703 u32 peer_sid; 5704 struct common_audit_data ad; 5705 struct lsm_network_audit net = {0,}; 5706 u8 secmark_active; 5707 u8 netlbl_active; 5708 u8 peerlbl_active; 5709 5710 if (!selinux_policycap_netpeer()) 5711 return NF_ACCEPT; 5712 5713 secmark_active = selinux_secmark_enabled(); 5714 netlbl_active = netlbl_enabled(); 5715 peerlbl_active = selinux_peerlbl_enabled(); 5716 if (!secmark_active && !peerlbl_active) 5717 return NF_ACCEPT; 5718 5719 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5720 return NF_DROP; 5721 5722 ad.type = LSM_AUDIT_DATA_NET; 5723 ad.u.net = &net; 5724 ad.u.net->netif = indev->ifindex; 5725 ad.u.net->family = family; 5726 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5727 return NF_DROP; 5728 5729 if (peerlbl_active) { 5730 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5731 addrp, family, peer_sid, &ad); 5732 if (err) { 5733 selinux_netlbl_err(skb, family, err, 1); 5734 return NF_DROP; 5735 } 5736 } 5737 5738 if (secmark_active) 5739 if (avc_has_perm(&selinux_state, 5740 peer_sid, skb->secmark, 5741 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5742 return NF_DROP; 5743 5744 if (netlbl_active) 5745 /* we do this in the FORWARD path and not the POST_ROUTING 5746 * path because we want to make sure we apply the necessary 5747 * labeling before IPsec is applied so we can leverage AH 5748 * protection */ 5749 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5750 return NF_DROP; 5751 5752 return NF_ACCEPT; 5753 } 5754 5755 static unsigned int selinux_ipv4_forward(void *priv, 5756 struct sk_buff *skb, 5757 const struct nf_hook_state *state) 5758 { 5759 return selinux_ip_forward(skb, state->in, PF_INET); 5760 } 5761 5762 #if IS_ENABLED(CONFIG_IPV6) 5763 static unsigned int selinux_ipv6_forward(void *priv, 5764 struct sk_buff *skb, 5765 const struct nf_hook_state *state) 5766 { 5767 return selinux_ip_forward(skb, state->in, PF_INET6); 5768 } 5769 #endif /* IPV6 */ 5770 5771 static unsigned int selinux_ip_output(struct sk_buff *skb, 5772 u16 family) 5773 { 5774 struct sock *sk; 5775 u32 sid; 5776 5777 if (!netlbl_enabled()) 5778 return NF_ACCEPT; 5779 5780 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5781 * because we want to make sure we apply the necessary labeling 5782 * before IPsec is applied so we can leverage AH protection */ 5783 sk = skb->sk; 5784 if (sk) { 5785 struct sk_security_struct *sksec; 5786 5787 if (sk_listener(sk)) 5788 /* if the socket is the listening state then this 5789 * packet is a SYN-ACK packet which means it needs to 5790 * be labeled based on the connection/request_sock and 5791 * not the parent socket. unfortunately, we can't 5792 * lookup the request_sock yet as it isn't queued on 5793 * the parent socket until after the SYN-ACK is sent. 5794 * the "solution" is to simply pass the packet as-is 5795 * as any IP option based labeling should be copied 5796 * from the initial connection request (in the IP 5797 * layer). it is far from ideal, but until we get a 5798 * security label in the packet itself this is the 5799 * best we can do. */ 5800 return NF_ACCEPT; 5801 5802 /* standard practice, label using the parent socket */ 5803 sksec = sk->sk_security; 5804 sid = sksec->sid; 5805 } else 5806 sid = SECINITSID_KERNEL; 5807 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5808 return NF_DROP; 5809 5810 return NF_ACCEPT; 5811 } 5812 5813 static unsigned int selinux_ipv4_output(void *priv, 5814 struct sk_buff *skb, 5815 const struct nf_hook_state *state) 5816 { 5817 return selinux_ip_output(skb, PF_INET); 5818 } 5819 5820 #if IS_ENABLED(CONFIG_IPV6) 5821 static unsigned int selinux_ipv6_output(void *priv, 5822 struct sk_buff *skb, 5823 const struct nf_hook_state *state) 5824 { 5825 return selinux_ip_output(skb, PF_INET6); 5826 } 5827 #endif /* IPV6 */ 5828 5829 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5830 int ifindex, 5831 u16 family) 5832 { 5833 struct sock *sk = skb_to_full_sk(skb); 5834 struct sk_security_struct *sksec; 5835 struct common_audit_data ad; 5836 struct lsm_network_audit net = {0,}; 5837 char *addrp; 5838 u8 proto; 5839 5840 if (sk == NULL) 5841 return NF_ACCEPT; 5842 sksec = sk->sk_security; 5843 5844 ad.type = LSM_AUDIT_DATA_NET; 5845 ad.u.net = &net; 5846 ad.u.net->netif = ifindex; 5847 ad.u.net->family = family; 5848 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5849 return NF_DROP; 5850 5851 if (selinux_secmark_enabled()) 5852 if (avc_has_perm(&selinux_state, 5853 sksec->sid, skb->secmark, 5854 SECCLASS_PACKET, PACKET__SEND, &ad)) 5855 return NF_DROP_ERR(-ECONNREFUSED); 5856 5857 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5858 return NF_DROP_ERR(-ECONNREFUSED); 5859 5860 return NF_ACCEPT; 5861 } 5862 5863 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5864 const struct net_device *outdev, 5865 u16 family) 5866 { 5867 u32 secmark_perm; 5868 u32 peer_sid; 5869 int ifindex = outdev->ifindex; 5870 struct sock *sk; 5871 struct common_audit_data ad; 5872 struct lsm_network_audit net = {0,}; 5873 char *addrp; 5874 u8 secmark_active; 5875 u8 peerlbl_active; 5876 5877 /* If any sort of compatibility mode is enabled then handoff processing 5878 * to the selinux_ip_postroute_compat() function to deal with the 5879 * special handling. We do this in an attempt to keep this function 5880 * as fast and as clean as possible. */ 5881 if (!selinux_policycap_netpeer()) 5882 return selinux_ip_postroute_compat(skb, ifindex, family); 5883 5884 secmark_active = selinux_secmark_enabled(); 5885 peerlbl_active = selinux_peerlbl_enabled(); 5886 if (!secmark_active && !peerlbl_active) 5887 return NF_ACCEPT; 5888 5889 sk = skb_to_full_sk(skb); 5890 5891 #ifdef CONFIG_XFRM 5892 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5893 * packet transformation so allow the packet to pass without any checks 5894 * since we'll have another chance to perform access control checks 5895 * when the packet is on it's final way out. 5896 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5897 * is NULL, in this case go ahead and apply access control. 5898 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5899 * TCP listening state we cannot wait until the XFRM processing 5900 * is done as we will miss out on the SA label if we do; 5901 * unfortunately, this means more work, but it is only once per 5902 * connection. */ 5903 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5904 !(sk && sk_listener(sk))) 5905 return NF_ACCEPT; 5906 #endif 5907 5908 if (sk == NULL) { 5909 /* Without an associated socket the packet is either coming 5910 * from the kernel or it is being forwarded; check the packet 5911 * to determine which and if the packet is being forwarded 5912 * query the packet directly to determine the security label. */ 5913 if (skb->skb_iif) { 5914 secmark_perm = PACKET__FORWARD_OUT; 5915 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5916 return NF_DROP; 5917 } else { 5918 secmark_perm = PACKET__SEND; 5919 peer_sid = SECINITSID_KERNEL; 5920 } 5921 } else if (sk_listener(sk)) { 5922 /* Locally generated packet but the associated socket is in the 5923 * listening state which means this is a SYN-ACK packet. In 5924 * this particular case the correct security label is assigned 5925 * to the connection/request_sock but unfortunately we can't 5926 * query the request_sock as it isn't queued on the parent 5927 * socket until after the SYN-ACK packet is sent; the only 5928 * viable choice is to regenerate the label like we do in 5929 * selinux_inet_conn_request(). See also selinux_ip_output() 5930 * for similar problems. */ 5931 u32 skb_sid; 5932 struct sk_security_struct *sksec; 5933 5934 sksec = sk->sk_security; 5935 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5936 return NF_DROP; 5937 /* At this point, if the returned skb peerlbl is SECSID_NULL 5938 * and the packet has been through at least one XFRM 5939 * transformation then we must be dealing with the "final" 5940 * form of labeled IPsec packet; since we've already applied 5941 * all of our access controls on this packet we can safely 5942 * pass the packet. */ 5943 if (skb_sid == SECSID_NULL) { 5944 switch (family) { 5945 case PF_INET: 5946 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5947 return NF_ACCEPT; 5948 break; 5949 case PF_INET6: 5950 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5951 return NF_ACCEPT; 5952 break; 5953 default: 5954 return NF_DROP_ERR(-ECONNREFUSED); 5955 } 5956 } 5957 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5958 return NF_DROP; 5959 secmark_perm = PACKET__SEND; 5960 } else { 5961 /* Locally generated packet, fetch the security label from the 5962 * associated socket. */ 5963 struct sk_security_struct *sksec = sk->sk_security; 5964 peer_sid = sksec->sid; 5965 secmark_perm = PACKET__SEND; 5966 } 5967 5968 ad.type = LSM_AUDIT_DATA_NET; 5969 ad.u.net = &net; 5970 ad.u.net->netif = ifindex; 5971 ad.u.net->family = family; 5972 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5973 return NF_DROP; 5974 5975 if (secmark_active) 5976 if (avc_has_perm(&selinux_state, 5977 peer_sid, skb->secmark, 5978 SECCLASS_PACKET, secmark_perm, &ad)) 5979 return NF_DROP_ERR(-ECONNREFUSED); 5980 5981 if (peerlbl_active) { 5982 u32 if_sid; 5983 u32 node_sid; 5984 5985 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5986 return NF_DROP; 5987 if (avc_has_perm(&selinux_state, 5988 peer_sid, if_sid, 5989 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5990 return NF_DROP_ERR(-ECONNREFUSED); 5991 5992 if (sel_netnode_sid(addrp, family, &node_sid)) 5993 return NF_DROP; 5994 if (avc_has_perm(&selinux_state, 5995 peer_sid, node_sid, 5996 SECCLASS_NODE, NODE__SENDTO, &ad)) 5997 return NF_DROP_ERR(-ECONNREFUSED); 5998 } 5999 6000 return NF_ACCEPT; 6001 } 6002 6003 static unsigned int selinux_ipv4_postroute(void *priv, 6004 struct sk_buff *skb, 6005 const struct nf_hook_state *state) 6006 { 6007 return selinux_ip_postroute(skb, state->out, PF_INET); 6008 } 6009 6010 #if IS_ENABLED(CONFIG_IPV6) 6011 static unsigned int selinux_ipv6_postroute(void *priv, 6012 struct sk_buff *skb, 6013 const struct nf_hook_state *state) 6014 { 6015 return selinux_ip_postroute(skb, state->out, PF_INET6); 6016 } 6017 #endif /* IPV6 */ 6018 6019 #endif /* CONFIG_NETFILTER */ 6020 6021 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 6022 { 6023 int rc = 0; 6024 unsigned int msg_len; 6025 unsigned int data_len = skb->len; 6026 unsigned char *data = skb->data; 6027 struct nlmsghdr *nlh; 6028 struct sk_security_struct *sksec = sk->sk_security; 6029 u16 sclass = sksec->sclass; 6030 u32 perm; 6031 6032 while (data_len >= nlmsg_total_size(0)) { 6033 nlh = (struct nlmsghdr *)data; 6034 6035 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 6036 * users which means we can't reject skb's with bogus 6037 * length fields; our solution is to follow what 6038 * netlink_rcv_skb() does and simply skip processing at 6039 * messages with length fields that are clearly junk 6040 */ 6041 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 6042 return 0; 6043 6044 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 6045 if (rc == 0) { 6046 rc = sock_has_perm(sk, perm); 6047 if (rc) 6048 return rc; 6049 } else if (rc == -EINVAL) { 6050 /* -EINVAL is a missing msg/perm mapping */ 6051 pr_warn_ratelimited("SELinux: unrecognized netlink" 6052 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 6053 " pid=%d comm=%s\n", 6054 sk->sk_protocol, nlh->nlmsg_type, 6055 secclass_map[sclass - 1].name, 6056 task_pid_nr(current), current->comm); 6057 if (enforcing_enabled(&selinux_state) && 6058 !security_get_allow_unknown(&selinux_state)) 6059 return rc; 6060 rc = 0; 6061 } else if (rc == -ENOENT) { 6062 /* -ENOENT is a missing socket/class mapping, ignore */ 6063 rc = 0; 6064 } else { 6065 return rc; 6066 } 6067 6068 /* move to the next message after applying netlink padding */ 6069 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 6070 if (msg_len >= data_len) 6071 return 0; 6072 data_len -= msg_len; 6073 data += msg_len; 6074 } 6075 6076 return rc; 6077 } 6078 6079 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 6080 { 6081 isec->sclass = sclass; 6082 isec->sid = current_sid(); 6083 } 6084 6085 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 6086 u32 perms) 6087 { 6088 struct ipc_security_struct *isec; 6089 struct common_audit_data ad; 6090 u32 sid = current_sid(); 6091 6092 isec = selinux_ipc(ipc_perms); 6093 6094 ad.type = LSM_AUDIT_DATA_IPC; 6095 ad.u.ipc_id = ipc_perms->key; 6096 6097 return avc_has_perm(&selinux_state, 6098 sid, isec->sid, isec->sclass, perms, &ad); 6099 } 6100 6101 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 6102 { 6103 struct msg_security_struct *msec; 6104 6105 msec = selinux_msg_msg(msg); 6106 msec->sid = SECINITSID_UNLABELED; 6107 6108 return 0; 6109 } 6110 6111 /* message queue security operations */ 6112 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 6113 { 6114 struct ipc_security_struct *isec; 6115 struct common_audit_data ad; 6116 u32 sid = current_sid(); 6117 int rc; 6118 6119 isec = selinux_ipc(msq); 6120 ipc_init_security(isec, SECCLASS_MSGQ); 6121 6122 ad.type = LSM_AUDIT_DATA_IPC; 6123 ad.u.ipc_id = msq->key; 6124 6125 rc = avc_has_perm(&selinux_state, 6126 sid, isec->sid, SECCLASS_MSGQ, 6127 MSGQ__CREATE, &ad); 6128 return rc; 6129 } 6130 6131 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 6132 { 6133 struct ipc_security_struct *isec; 6134 struct common_audit_data ad; 6135 u32 sid = current_sid(); 6136 6137 isec = selinux_ipc(msq); 6138 6139 ad.type = LSM_AUDIT_DATA_IPC; 6140 ad.u.ipc_id = msq->key; 6141 6142 return avc_has_perm(&selinux_state, 6143 sid, isec->sid, SECCLASS_MSGQ, 6144 MSGQ__ASSOCIATE, &ad); 6145 } 6146 6147 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 6148 { 6149 int err; 6150 int perms; 6151 6152 switch (cmd) { 6153 case IPC_INFO: 6154 case MSG_INFO: 6155 /* No specific object, just general system-wide information. */ 6156 return avc_has_perm(&selinux_state, 6157 current_sid(), SECINITSID_KERNEL, 6158 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6159 case IPC_STAT: 6160 case MSG_STAT: 6161 case MSG_STAT_ANY: 6162 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6163 break; 6164 case IPC_SET: 6165 perms = MSGQ__SETATTR; 6166 break; 6167 case IPC_RMID: 6168 perms = MSGQ__DESTROY; 6169 break; 6170 default: 6171 return 0; 6172 } 6173 6174 err = ipc_has_perm(msq, perms); 6175 return err; 6176 } 6177 6178 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6179 { 6180 struct ipc_security_struct *isec; 6181 struct msg_security_struct *msec; 6182 struct common_audit_data ad; 6183 u32 sid = current_sid(); 6184 int rc; 6185 6186 isec = selinux_ipc(msq); 6187 msec = selinux_msg_msg(msg); 6188 6189 /* 6190 * First time through, need to assign label to the message 6191 */ 6192 if (msec->sid == SECINITSID_UNLABELED) { 6193 /* 6194 * Compute new sid based on current process and 6195 * message queue this message will be stored in 6196 */ 6197 rc = security_transition_sid(&selinux_state, sid, isec->sid, 6198 SECCLASS_MSG, NULL, &msec->sid); 6199 if (rc) 6200 return rc; 6201 } 6202 6203 ad.type = LSM_AUDIT_DATA_IPC; 6204 ad.u.ipc_id = msq->key; 6205 6206 /* Can this process write to the queue? */ 6207 rc = avc_has_perm(&selinux_state, 6208 sid, isec->sid, SECCLASS_MSGQ, 6209 MSGQ__WRITE, &ad); 6210 if (!rc) 6211 /* Can this process send the message */ 6212 rc = avc_has_perm(&selinux_state, 6213 sid, msec->sid, SECCLASS_MSG, 6214 MSG__SEND, &ad); 6215 if (!rc) 6216 /* Can the message be put in the queue? */ 6217 rc = avc_has_perm(&selinux_state, 6218 msec->sid, isec->sid, SECCLASS_MSGQ, 6219 MSGQ__ENQUEUE, &ad); 6220 6221 return rc; 6222 } 6223 6224 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6225 struct task_struct *target, 6226 long type, int mode) 6227 { 6228 struct ipc_security_struct *isec; 6229 struct msg_security_struct *msec; 6230 struct common_audit_data ad; 6231 u32 sid = task_sid_subj(target); 6232 int rc; 6233 6234 isec = selinux_ipc(msq); 6235 msec = selinux_msg_msg(msg); 6236 6237 ad.type = LSM_AUDIT_DATA_IPC; 6238 ad.u.ipc_id = msq->key; 6239 6240 rc = avc_has_perm(&selinux_state, 6241 sid, isec->sid, 6242 SECCLASS_MSGQ, MSGQ__READ, &ad); 6243 if (!rc) 6244 rc = avc_has_perm(&selinux_state, 6245 sid, msec->sid, 6246 SECCLASS_MSG, MSG__RECEIVE, &ad); 6247 return rc; 6248 } 6249 6250 /* Shared Memory security operations */ 6251 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6252 { 6253 struct ipc_security_struct *isec; 6254 struct common_audit_data ad; 6255 u32 sid = current_sid(); 6256 int rc; 6257 6258 isec = selinux_ipc(shp); 6259 ipc_init_security(isec, SECCLASS_SHM); 6260 6261 ad.type = LSM_AUDIT_DATA_IPC; 6262 ad.u.ipc_id = shp->key; 6263 6264 rc = avc_has_perm(&selinux_state, 6265 sid, isec->sid, SECCLASS_SHM, 6266 SHM__CREATE, &ad); 6267 return rc; 6268 } 6269 6270 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6271 { 6272 struct ipc_security_struct *isec; 6273 struct common_audit_data ad; 6274 u32 sid = current_sid(); 6275 6276 isec = selinux_ipc(shp); 6277 6278 ad.type = LSM_AUDIT_DATA_IPC; 6279 ad.u.ipc_id = shp->key; 6280 6281 return avc_has_perm(&selinux_state, 6282 sid, isec->sid, SECCLASS_SHM, 6283 SHM__ASSOCIATE, &ad); 6284 } 6285 6286 /* Note, at this point, shp is locked down */ 6287 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6288 { 6289 int perms; 6290 int err; 6291 6292 switch (cmd) { 6293 case IPC_INFO: 6294 case SHM_INFO: 6295 /* No specific object, just general system-wide information. */ 6296 return avc_has_perm(&selinux_state, 6297 current_sid(), SECINITSID_KERNEL, 6298 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6299 case IPC_STAT: 6300 case SHM_STAT: 6301 case SHM_STAT_ANY: 6302 perms = SHM__GETATTR | SHM__ASSOCIATE; 6303 break; 6304 case IPC_SET: 6305 perms = SHM__SETATTR; 6306 break; 6307 case SHM_LOCK: 6308 case SHM_UNLOCK: 6309 perms = SHM__LOCK; 6310 break; 6311 case IPC_RMID: 6312 perms = SHM__DESTROY; 6313 break; 6314 default: 6315 return 0; 6316 } 6317 6318 err = ipc_has_perm(shp, perms); 6319 return err; 6320 } 6321 6322 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6323 char __user *shmaddr, int shmflg) 6324 { 6325 u32 perms; 6326 6327 if (shmflg & SHM_RDONLY) 6328 perms = SHM__READ; 6329 else 6330 perms = SHM__READ | SHM__WRITE; 6331 6332 return ipc_has_perm(shp, perms); 6333 } 6334 6335 /* Semaphore security operations */ 6336 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6337 { 6338 struct ipc_security_struct *isec; 6339 struct common_audit_data ad; 6340 u32 sid = current_sid(); 6341 int rc; 6342 6343 isec = selinux_ipc(sma); 6344 ipc_init_security(isec, SECCLASS_SEM); 6345 6346 ad.type = LSM_AUDIT_DATA_IPC; 6347 ad.u.ipc_id = sma->key; 6348 6349 rc = avc_has_perm(&selinux_state, 6350 sid, isec->sid, SECCLASS_SEM, 6351 SEM__CREATE, &ad); 6352 return rc; 6353 } 6354 6355 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6356 { 6357 struct ipc_security_struct *isec; 6358 struct common_audit_data ad; 6359 u32 sid = current_sid(); 6360 6361 isec = selinux_ipc(sma); 6362 6363 ad.type = LSM_AUDIT_DATA_IPC; 6364 ad.u.ipc_id = sma->key; 6365 6366 return avc_has_perm(&selinux_state, 6367 sid, isec->sid, SECCLASS_SEM, 6368 SEM__ASSOCIATE, &ad); 6369 } 6370 6371 /* Note, at this point, sma is locked down */ 6372 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6373 { 6374 int err; 6375 u32 perms; 6376 6377 switch (cmd) { 6378 case IPC_INFO: 6379 case SEM_INFO: 6380 /* No specific object, just general system-wide information. */ 6381 return avc_has_perm(&selinux_state, 6382 current_sid(), SECINITSID_KERNEL, 6383 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6384 case GETPID: 6385 case GETNCNT: 6386 case GETZCNT: 6387 perms = SEM__GETATTR; 6388 break; 6389 case GETVAL: 6390 case GETALL: 6391 perms = SEM__READ; 6392 break; 6393 case SETVAL: 6394 case SETALL: 6395 perms = SEM__WRITE; 6396 break; 6397 case IPC_RMID: 6398 perms = SEM__DESTROY; 6399 break; 6400 case IPC_SET: 6401 perms = SEM__SETATTR; 6402 break; 6403 case IPC_STAT: 6404 case SEM_STAT: 6405 case SEM_STAT_ANY: 6406 perms = SEM__GETATTR | SEM__ASSOCIATE; 6407 break; 6408 default: 6409 return 0; 6410 } 6411 6412 err = ipc_has_perm(sma, perms); 6413 return err; 6414 } 6415 6416 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6417 struct sembuf *sops, unsigned nsops, int alter) 6418 { 6419 u32 perms; 6420 6421 if (alter) 6422 perms = SEM__READ | SEM__WRITE; 6423 else 6424 perms = SEM__READ; 6425 6426 return ipc_has_perm(sma, perms); 6427 } 6428 6429 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6430 { 6431 u32 av = 0; 6432 6433 av = 0; 6434 if (flag & S_IRUGO) 6435 av |= IPC__UNIX_READ; 6436 if (flag & S_IWUGO) 6437 av |= IPC__UNIX_WRITE; 6438 6439 if (av == 0) 6440 return 0; 6441 6442 return ipc_has_perm(ipcp, av); 6443 } 6444 6445 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6446 { 6447 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6448 *secid = isec->sid; 6449 } 6450 6451 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6452 { 6453 if (inode) 6454 inode_doinit_with_dentry(inode, dentry); 6455 } 6456 6457 static int selinux_getprocattr(struct task_struct *p, 6458 char *name, char **value) 6459 { 6460 const struct task_security_struct *__tsec; 6461 u32 sid; 6462 int error; 6463 unsigned len; 6464 6465 rcu_read_lock(); 6466 __tsec = selinux_cred(__task_cred(p)); 6467 6468 if (current != p) { 6469 error = avc_has_perm(&selinux_state, 6470 current_sid(), __tsec->sid, 6471 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6472 if (error) 6473 goto bad; 6474 } 6475 6476 if (!strcmp(name, "current")) 6477 sid = __tsec->sid; 6478 else if (!strcmp(name, "prev")) 6479 sid = __tsec->osid; 6480 else if (!strcmp(name, "exec")) 6481 sid = __tsec->exec_sid; 6482 else if (!strcmp(name, "fscreate")) 6483 sid = __tsec->create_sid; 6484 else if (!strcmp(name, "keycreate")) 6485 sid = __tsec->keycreate_sid; 6486 else if (!strcmp(name, "sockcreate")) 6487 sid = __tsec->sockcreate_sid; 6488 else { 6489 error = -EINVAL; 6490 goto bad; 6491 } 6492 rcu_read_unlock(); 6493 6494 if (!sid) 6495 return 0; 6496 6497 error = security_sid_to_context(&selinux_state, sid, value, &len); 6498 if (error) 6499 return error; 6500 return len; 6501 6502 bad: 6503 rcu_read_unlock(); 6504 return error; 6505 } 6506 6507 static int selinux_setprocattr(const char *name, void *value, size_t size) 6508 { 6509 struct task_security_struct *tsec; 6510 struct cred *new; 6511 u32 mysid = current_sid(), sid = 0, ptsid; 6512 int error; 6513 char *str = value; 6514 6515 /* 6516 * Basic control over ability to set these attributes at all. 6517 */ 6518 if (!strcmp(name, "exec")) 6519 error = avc_has_perm(&selinux_state, 6520 mysid, mysid, SECCLASS_PROCESS, 6521 PROCESS__SETEXEC, NULL); 6522 else if (!strcmp(name, "fscreate")) 6523 error = avc_has_perm(&selinux_state, 6524 mysid, mysid, SECCLASS_PROCESS, 6525 PROCESS__SETFSCREATE, NULL); 6526 else if (!strcmp(name, "keycreate")) 6527 error = avc_has_perm(&selinux_state, 6528 mysid, mysid, SECCLASS_PROCESS, 6529 PROCESS__SETKEYCREATE, NULL); 6530 else if (!strcmp(name, "sockcreate")) 6531 error = avc_has_perm(&selinux_state, 6532 mysid, mysid, SECCLASS_PROCESS, 6533 PROCESS__SETSOCKCREATE, NULL); 6534 else if (!strcmp(name, "current")) 6535 error = avc_has_perm(&selinux_state, 6536 mysid, mysid, SECCLASS_PROCESS, 6537 PROCESS__SETCURRENT, NULL); 6538 else 6539 error = -EINVAL; 6540 if (error) 6541 return error; 6542 6543 /* Obtain a SID for the context, if one was specified. */ 6544 if (size && str[0] && str[0] != '\n') { 6545 if (str[size-1] == '\n') { 6546 str[size-1] = 0; 6547 size--; 6548 } 6549 error = security_context_to_sid(&selinux_state, value, size, 6550 &sid, GFP_KERNEL); 6551 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6552 if (!has_cap_mac_admin(true)) { 6553 struct audit_buffer *ab; 6554 size_t audit_size; 6555 6556 /* We strip a nul only if it is at the end, otherwise the 6557 * context contains a nul and we should audit that */ 6558 if (str[size - 1] == '\0') 6559 audit_size = size - 1; 6560 else 6561 audit_size = size; 6562 ab = audit_log_start(audit_context(), 6563 GFP_ATOMIC, 6564 AUDIT_SELINUX_ERR); 6565 audit_log_format(ab, "op=fscreate invalid_context="); 6566 audit_log_n_untrustedstring(ab, value, audit_size); 6567 audit_log_end(ab); 6568 6569 return error; 6570 } 6571 error = security_context_to_sid_force( 6572 &selinux_state, 6573 value, size, &sid); 6574 } 6575 if (error) 6576 return error; 6577 } 6578 6579 new = prepare_creds(); 6580 if (!new) 6581 return -ENOMEM; 6582 6583 /* Permission checking based on the specified context is 6584 performed during the actual operation (execve, 6585 open/mkdir/...), when we know the full context of the 6586 operation. See selinux_bprm_creds_for_exec for the execve 6587 checks and may_create for the file creation checks. The 6588 operation will then fail if the context is not permitted. */ 6589 tsec = selinux_cred(new); 6590 if (!strcmp(name, "exec")) { 6591 tsec->exec_sid = sid; 6592 } else if (!strcmp(name, "fscreate")) { 6593 tsec->create_sid = sid; 6594 } else if (!strcmp(name, "keycreate")) { 6595 if (sid) { 6596 error = avc_has_perm(&selinux_state, mysid, sid, 6597 SECCLASS_KEY, KEY__CREATE, NULL); 6598 if (error) 6599 goto abort_change; 6600 } 6601 tsec->keycreate_sid = sid; 6602 } else if (!strcmp(name, "sockcreate")) { 6603 tsec->sockcreate_sid = sid; 6604 } else if (!strcmp(name, "current")) { 6605 error = -EINVAL; 6606 if (sid == 0) 6607 goto abort_change; 6608 6609 /* Only allow single threaded processes to change context */ 6610 error = -EPERM; 6611 if (!current_is_single_threaded()) { 6612 error = security_bounded_transition(&selinux_state, 6613 tsec->sid, sid); 6614 if (error) 6615 goto abort_change; 6616 } 6617 6618 /* Check permissions for the transition. */ 6619 error = avc_has_perm(&selinux_state, 6620 tsec->sid, sid, SECCLASS_PROCESS, 6621 PROCESS__DYNTRANSITION, NULL); 6622 if (error) 6623 goto abort_change; 6624 6625 /* Check for ptracing, and update the task SID if ok. 6626 Otherwise, leave SID unchanged and fail. */ 6627 ptsid = ptrace_parent_sid(); 6628 if (ptsid != 0) { 6629 error = avc_has_perm(&selinux_state, 6630 ptsid, sid, SECCLASS_PROCESS, 6631 PROCESS__PTRACE, NULL); 6632 if (error) 6633 goto abort_change; 6634 } 6635 6636 tsec->sid = sid; 6637 } else { 6638 error = -EINVAL; 6639 goto abort_change; 6640 } 6641 6642 commit_creds(new); 6643 return size; 6644 6645 abort_change: 6646 abort_creds(new); 6647 return error; 6648 } 6649 6650 static int selinux_ismaclabel(const char *name) 6651 { 6652 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6653 } 6654 6655 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6656 { 6657 return security_sid_to_context(&selinux_state, secid, 6658 secdata, seclen); 6659 } 6660 6661 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6662 { 6663 return security_context_to_sid(&selinux_state, secdata, seclen, 6664 secid, GFP_KERNEL); 6665 } 6666 6667 static void selinux_release_secctx(char *secdata, u32 seclen) 6668 { 6669 kfree(secdata); 6670 } 6671 6672 static void selinux_inode_invalidate_secctx(struct inode *inode) 6673 { 6674 struct inode_security_struct *isec = selinux_inode(inode); 6675 6676 spin_lock(&isec->lock); 6677 isec->initialized = LABEL_INVALID; 6678 spin_unlock(&isec->lock); 6679 } 6680 6681 /* 6682 * called with inode->i_mutex locked 6683 */ 6684 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6685 { 6686 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6687 ctx, ctxlen, 0); 6688 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6689 return rc == -EOPNOTSUPP ? 0 : rc; 6690 } 6691 6692 /* 6693 * called with inode->i_mutex locked 6694 */ 6695 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6696 { 6697 return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SELINUX, 6698 ctx, ctxlen, 0); 6699 } 6700 6701 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6702 { 6703 int len = 0; 6704 len = selinux_inode_getsecurity(&init_user_ns, inode, 6705 XATTR_SELINUX_SUFFIX, ctx, true); 6706 if (len < 0) 6707 return len; 6708 *ctxlen = len; 6709 return 0; 6710 } 6711 #ifdef CONFIG_KEYS 6712 6713 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6714 unsigned long flags) 6715 { 6716 const struct task_security_struct *tsec; 6717 struct key_security_struct *ksec; 6718 6719 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6720 if (!ksec) 6721 return -ENOMEM; 6722 6723 tsec = selinux_cred(cred); 6724 if (tsec->keycreate_sid) 6725 ksec->sid = tsec->keycreate_sid; 6726 else 6727 ksec->sid = tsec->sid; 6728 6729 k->security = ksec; 6730 return 0; 6731 } 6732 6733 static void selinux_key_free(struct key *k) 6734 { 6735 struct key_security_struct *ksec = k->security; 6736 6737 k->security = NULL; 6738 kfree(ksec); 6739 } 6740 6741 static int selinux_key_permission(key_ref_t key_ref, 6742 const struct cred *cred, 6743 enum key_need_perm need_perm) 6744 { 6745 struct key *key; 6746 struct key_security_struct *ksec; 6747 u32 perm, sid; 6748 6749 switch (need_perm) { 6750 case KEY_NEED_VIEW: 6751 perm = KEY__VIEW; 6752 break; 6753 case KEY_NEED_READ: 6754 perm = KEY__READ; 6755 break; 6756 case KEY_NEED_WRITE: 6757 perm = KEY__WRITE; 6758 break; 6759 case KEY_NEED_SEARCH: 6760 perm = KEY__SEARCH; 6761 break; 6762 case KEY_NEED_LINK: 6763 perm = KEY__LINK; 6764 break; 6765 case KEY_NEED_SETATTR: 6766 perm = KEY__SETATTR; 6767 break; 6768 case KEY_NEED_UNLINK: 6769 case KEY_SYSADMIN_OVERRIDE: 6770 case KEY_AUTHTOKEN_OVERRIDE: 6771 case KEY_DEFER_PERM_CHECK: 6772 return 0; 6773 default: 6774 WARN_ON(1); 6775 return -EPERM; 6776 6777 } 6778 6779 sid = cred_sid(cred); 6780 key = key_ref_to_ptr(key_ref); 6781 ksec = key->security; 6782 6783 return avc_has_perm(&selinux_state, 6784 sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6785 } 6786 6787 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6788 { 6789 struct key_security_struct *ksec = key->security; 6790 char *context = NULL; 6791 unsigned len; 6792 int rc; 6793 6794 rc = security_sid_to_context(&selinux_state, ksec->sid, 6795 &context, &len); 6796 if (!rc) 6797 rc = len; 6798 *_buffer = context; 6799 return rc; 6800 } 6801 6802 #ifdef CONFIG_KEY_NOTIFICATIONS 6803 static int selinux_watch_key(struct key *key) 6804 { 6805 struct key_security_struct *ksec = key->security; 6806 u32 sid = current_sid(); 6807 6808 return avc_has_perm(&selinux_state, 6809 sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6810 } 6811 #endif 6812 #endif 6813 6814 #ifdef CONFIG_SECURITY_INFINIBAND 6815 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6816 { 6817 struct common_audit_data ad; 6818 int err; 6819 u32 sid = 0; 6820 struct ib_security_struct *sec = ib_sec; 6821 struct lsm_ibpkey_audit ibpkey; 6822 6823 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6824 if (err) 6825 return err; 6826 6827 ad.type = LSM_AUDIT_DATA_IBPKEY; 6828 ibpkey.subnet_prefix = subnet_prefix; 6829 ibpkey.pkey = pkey_val; 6830 ad.u.ibpkey = &ibpkey; 6831 return avc_has_perm(&selinux_state, 6832 sec->sid, sid, 6833 SECCLASS_INFINIBAND_PKEY, 6834 INFINIBAND_PKEY__ACCESS, &ad); 6835 } 6836 6837 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6838 u8 port_num) 6839 { 6840 struct common_audit_data ad; 6841 int err; 6842 u32 sid = 0; 6843 struct ib_security_struct *sec = ib_sec; 6844 struct lsm_ibendport_audit ibendport; 6845 6846 err = security_ib_endport_sid(&selinux_state, dev_name, port_num, 6847 &sid); 6848 6849 if (err) 6850 return err; 6851 6852 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6853 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name)); 6854 ibendport.port = port_num; 6855 ad.u.ibendport = &ibendport; 6856 return avc_has_perm(&selinux_state, 6857 sec->sid, sid, 6858 SECCLASS_INFINIBAND_ENDPORT, 6859 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6860 } 6861 6862 static int selinux_ib_alloc_security(void **ib_sec) 6863 { 6864 struct ib_security_struct *sec; 6865 6866 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6867 if (!sec) 6868 return -ENOMEM; 6869 sec->sid = current_sid(); 6870 6871 *ib_sec = sec; 6872 return 0; 6873 } 6874 6875 static void selinux_ib_free_security(void *ib_sec) 6876 { 6877 kfree(ib_sec); 6878 } 6879 #endif 6880 6881 #ifdef CONFIG_BPF_SYSCALL 6882 static int selinux_bpf(int cmd, union bpf_attr *attr, 6883 unsigned int size) 6884 { 6885 u32 sid = current_sid(); 6886 int ret; 6887 6888 switch (cmd) { 6889 case BPF_MAP_CREATE: 6890 ret = avc_has_perm(&selinux_state, 6891 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6892 NULL); 6893 break; 6894 case BPF_PROG_LOAD: 6895 ret = avc_has_perm(&selinux_state, 6896 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6897 NULL); 6898 break; 6899 default: 6900 ret = 0; 6901 break; 6902 } 6903 6904 return ret; 6905 } 6906 6907 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6908 { 6909 u32 av = 0; 6910 6911 if (fmode & FMODE_READ) 6912 av |= BPF__MAP_READ; 6913 if (fmode & FMODE_WRITE) 6914 av |= BPF__MAP_WRITE; 6915 return av; 6916 } 6917 6918 /* This function will check the file pass through unix socket or binder to see 6919 * if it is a bpf related object. And apply correspinding checks on the bpf 6920 * object based on the type. The bpf maps and programs, not like other files and 6921 * socket, are using a shared anonymous inode inside the kernel as their inode. 6922 * So checking that inode cannot identify if the process have privilege to 6923 * access the bpf object and that's why we have to add this additional check in 6924 * selinux_file_receive and selinux_binder_transfer_files. 6925 */ 6926 static int bpf_fd_pass(struct file *file, u32 sid) 6927 { 6928 struct bpf_security_struct *bpfsec; 6929 struct bpf_prog *prog; 6930 struct bpf_map *map; 6931 int ret; 6932 6933 if (file->f_op == &bpf_map_fops) { 6934 map = file->private_data; 6935 bpfsec = map->security; 6936 ret = avc_has_perm(&selinux_state, 6937 sid, bpfsec->sid, SECCLASS_BPF, 6938 bpf_map_fmode_to_av(file->f_mode), NULL); 6939 if (ret) 6940 return ret; 6941 } else if (file->f_op == &bpf_prog_fops) { 6942 prog = file->private_data; 6943 bpfsec = prog->aux->security; 6944 ret = avc_has_perm(&selinux_state, 6945 sid, bpfsec->sid, SECCLASS_BPF, 6946 BPF__PROG_RUN, NULL); 6947 if (ret) 6948 return ret; 6949 } 6950 return 0; 6951 } 6952 6953 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6954 { 6955 u32 sid = current_sid(); 6956 struct bpf_security_struct *bpfsec; 6957 6958 bpfsec = map->security; 6959 return avc_has_perm(&selinux_state, 6960 sid, bpfsec->sid, SECCLASS_BPF, 6961 bpf_map_fmode_to_av(fmode), NULL); 6962 } 6963 6964 static int selinux_bpf_prog(struct bpf_prog *prog) 6965 { 6966 u32 sid = current_sid(); 6967 struct bpf_security_struct *bpfsec; 6968 6969 bpfsec = prog->aux->security; 6970 return avc_has_perm(&selinux_state, 6971 sid, bpfsec->sid, SECCLASS_BPF, 6972 BPF__PROG_RUN, NULL); 6973 } 6974 6975 static int selinux_bpf_map_alloc(struct bpf_map *map) 6976 { 6977 struct bpf_security_struct *bpfsec; 6978 6979 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6980 if (!bpfsec) 6981 return -ENOMEM; 6982 6983 bpfsec->sid = current_sid(); 6984 map->security = bpfsec; 6985 6986 return 0; 6987 } 6988 6989 static void selinux_bpf_map_free(struct bpf_map *map) 6990 { 6991 struct bpf_security_struct *bpfsec = map->security; 6992 6993 map->security = NULL; 6994 kfree(bpfsec); 6995 } 6996 6997 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6998 { 6999 struct bpf_security_struct *bpfsec; 7000 7001 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 7002 if (!bpfsec) 7003 return -ENOMEM; 7004 7005 bpfsec->sid = current_sid(); 7006 aux->security = bpfsec; 7007 7008 return 0; 7009 } 7010 7011 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 7012 { 7013 struct bpf_security_struct *bpfsec = aux->security; 7014 7015 aux->security = NULL; 7016 kfree(bpfsec); 7017 } 7018 #endif 7019 7020 static int selinux_lockdown(enum lockdown_reason what) 7021 { 7022 struct common_audit_data ad; 7023 u32 sid = current_sid(); 7024 int invalid_reason = (what <= LOCKDOWN_NONE) || 7025 (what == LOCKDOWN_INTEGRITY_MAX) || 7026 (what >= LOCKDOWN_CONFIDENTIALITY_MAX); 7027 7028 if (WARN(invalid_reason, "Invalid lockdown reason")) { 7029 audit_log(audit_context(), 7030 GFP_ATOMIC, AUDIT_SELINUX_ERR, 7031 "lockdown_reason=invalid"); 7032 return -EINVAL; 7033 } 7034 7035 ad.type = LSM_AUDIT_DATA_LOCKDOWN; 7036 ad.u.reason = what; 7037 7038 if (what <= LOCKDOWN_INTEGRITY_MAX) 7039 return avc_has_perm(&selinux_state, 7040 sid, sid, SECCLASS_LOCKDOWN, 7041 LOCKDOWN__INTEGRITY, &ad); 7042 else 7043 return avc_has_perm(&selinux_state, 7044 sid, sid, SECCLASS_LOCKDOWN, 7045 LOCKDOWN__CONFIDENTIALITY, &ad); 7046 } 7047 7048 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = { 7049 .lbs_cred = sizeof(struct task_security_struct), 7050 .lbs_file = sizeof(struct file_security_struct), 7051 .lbs_inode = sizeof(struct inode_security_struct), 7052 .lbs_ipc = sizeof(struct ipc_security_struct), 7053 .lbs_msg_msg = sizeof(struct msg_security_struct), 7054 .lbs_superblock = sizeof(struct superblock_security_struct), 7055 }; 7056 7057 #ifdef CONFIG_PERF_EVENTS 7058 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 7059 { 7060 u32 requested, sid = current_sid(); 7061 7062 if (type == PERF_SECURITY_OPEN) 7063 requested = PERF_EVENT__OPEN; 7064 else if (type == PERF_SECURITY_CPU) 7065 requested = PERF_EVENT__CPU; 7066 else if (type == PERF_SECURITY_KERNEL) 7067 requested = PERF_EVENT__KERNEL; 7068 else if (type == PERF_SECURITY_TRACEPOINT) 7069 requested = PERF_EVENT__TRACEPOINT; 7070 else 7071 return -EINVAL; 7072 7073 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT, 7074 requested, NULL); 7075 } 7076 7077 static int selinux_perf_event_alloc(struct perf_event *event) 7078 { 7079 struct perf_event_security_struct *perfsec; 7080 7081 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 7082 if (!perfsec) 7083 return -ENOMEM; 7084 7085 perfsec->sid = current_sid(); 7086 event->security = perfsec; 7087 7088 return 0; 7089 } 7090 7091 static void selinux_perf_event_free(struct perf_event *event) 7092 { 7093 struct perf_event_security_struct *perfsec = event->security; 7094 7095 event->security = NULL; 7096 kfree(perfsec); 7097 } 7098 7099 static int selinux_perf_event_read(struct perf_event *event) 7100 { 7101 struct perf_event_security_struct *perfsec = event->security; 7102 u32 sid = current_sid(); 7103 7104 return avc_has_perm(&selinux_state, sid, perfsec->sid, 7105 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 7106 } 7107 7108 static int selinux_perf_event_write(struct perf_event *event) 7109 { 7110 struct perf_event_security_struct *perfsec = event->security; 7111 u32 sid = current_sid(); 7112 7113 return avc_has_perm(&selinux_state, sid, perfsec->sid, 7114 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 7115 } 7116 #endif 7117 7118 /* 7119 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 7120 * 1. any hooks that don't belong to (2.) or (3.) below, 7121 * 2. hooks that both access structures allocated by other hooks, and allocate 7122 * structures that can be later accessed by other hooks (mostly "cloning" 7123 * hooks), 7124 * 3. hooks that only allocate structures that can be later accessed by other 7125 * hooks ("allocating" hooks). 7126 * 7127 * Please follow block comment delimiters in the list to keep this order. 7128 * 7129 * This ordering is needed for SELinux runtime disable to work at least somewhat 7130 * safely. Breaking the ordering rules above might lead to NULL pointer derefs 7131 * when disabling SELinux at runtime. 7132 */ 7133 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { 7134 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 7135 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 7136 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 7137 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 7138 7139 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 7140 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 7141 LSM_HOOK_INIT(capget, selinux_capget), 7142 LSM_HOOK_INIT(capset, selinux_capset), 7143 LSM_HOOK_INIT(capable, selinux_capable), 7144 LSM_HOOK_INIT(quotactl, selinux_quotactl), 7145 LSM_HOOK_INIT(quota_on, selinux_quota_on), 7146 LSM_HOOK_INIT(syslog, selinux_syslog), 7147 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 7148 7149 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 7150 7151 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 7152 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 7153 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 7154 7155 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 7156 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 7157 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 7158 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 7159 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 7160 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 7161 LSM_HOOK_INIT(sb_mount, selinux_mount), 7162 LSM_HOOK_INIT(sb_umount, selinux_umount), 7163 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7164 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7165 7166 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7167 7168 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7169 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7170 7171 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7172 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7173 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7174 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7175 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7176 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7177 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7178 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7179 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7180 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7181 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7182 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7183 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7184 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7185 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7186 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7187 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7188 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7189 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7190 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7191 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7192 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7193 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7194 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7195 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7196 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7197 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7198 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7199 7200 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7201 7202 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7203 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7204 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7205 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7206 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7207 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7208 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7209 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7210 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7211 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7212 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7213 7214 LSM_HOOK_INIT(file_open, selinux_file_open), 7215 7216 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7217 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7218 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7219 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7220 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7221 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7222 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7223 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7224 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7225 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7226 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7227 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7228 LSM_HOOK_INIT(task_getsecid_subj, selinux_task_getsecid_subj), 7229 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), 7230 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7231 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7232 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7233 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7234 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7235 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7236 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7237 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7238 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7239 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7240 7241 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7242 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7243 7244 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7245 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7246 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7247 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7248 7249 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7250 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7251 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7252 7253 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7254 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7255 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7256 7257 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7258 7259 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7260 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7261 7262 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7263 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7264 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7265 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7266 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7267 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7268 7269 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7270 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7271 7272 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7273 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7274 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7275 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7276 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7277 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7278 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7279 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7280 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7281 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7282 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7283 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7284 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7285 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7286 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7287 LSM_HOOK_INIT(socket_getpeersec_stream, 7288 selinux_socket_getpeersec_stream), 7289 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7290 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7291 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7292 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7293 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7294 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7295 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7296 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7297 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7298 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7299 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7300 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7301 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7302 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7303 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7304 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7305 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7306 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7307 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7308 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7309 #ifdef CONFIG_SECURITY_INFINIBAND 7310 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7311 LSM_HOOK_INIT(ib_endport_manage_subnet, 7312 selinux_ib_endport_manage_subnet), 7313 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7314 #endif 7315 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7316 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7317 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7318 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7319 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7320 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7321 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7322 selinux_xfrm_state_pol_flow_match), 7323 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7324 #endif 7325 7326 #ifdef CONFIG_KEYS 7327 LSM_HOOK_INIT(key_free, selinux_key_free), 7328 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7329 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7330 #ifdef CONFIG_KEY_NOTIFICATIONS 7331 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7332 #endif 7333 #endif 7334 7335 #ifdef CONFIG_AUDIT 7336 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7337 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7338 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7339 #endif 7340 7341 #ifdef CONFIG_BPF_SYSCALL 7342 LSM_HOOK_INIT(bpf, selinux_bpf), 7343 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7344 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7345 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7346 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7347 #endif 7348 7349 #ifdef CONFIG_PERF_EVENTS 7350 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7351 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7352 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7353 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7354 #endif 7355 7356 LSM_HOOK_INIT(locked_down, selinux_lockdown), 7357 7358 /* 7359 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7360 */ 7361 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7362 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7363 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7364 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt), 7365 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7366 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7367 #endif 7368 7369 /* 7370 * PUT "ALLOCATING" HOOKS HERE 7371 */ 7372 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7373 LSM_HOOK_INIT(msg_queue_alloc_security, 7374 selinux_msg_queue_alloc_security), 7375 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7376 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7377 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7378 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7379 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7380 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7381 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7382 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7383 #ifdef CONFIG_SECURITY_INFINIBAND 7384 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7385 #endif 7386 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7387 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7388 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7389 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7390 selinux_xfrm_state_alloc_acquire), 7391 #endif 7392 #ifdef CONFIG_KEYS 7393 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7394 #endif 7395 #ifdef CONFIG_AUDIT 7396 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7397 #endif 7398 #ifdef CONFIG_BPF_SYSCALL 7399 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7400 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7401 #endif 7402 #ifdef CONFIG_PERF_EVENTS 7403 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7404 #endif 7405 }; 7406 7407 static __init int selinux_init(void) 7408 { 7409 pr_info("SELinux: Initializing.\n"); 7410 7411 memset(&selinux_state, 0, sizeof(selinux_state)); 7412 enforcing_set(&selinux_state, selinux_enforcing_boot); 7413 checkreqprot_set(&selinux_state, selinux_checkreqprot_boot); 7414 selinux_avc_init(&selinux_state.avc); 7415 mutex_init(&selinux_state.status_lock); 7416 mutex_init(&selinux_state.policy_mutex); 7417 7418 /* Set the security state for the initial task. */ 7419 cred_init_security(); 7420 7421 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7422 7423 avc_init(); 7424 7425 avtab_cache_init(); 7426 7427 ebitmap_cache_init(); 7428 7429 hashtab_cache_init(); 7430 7431 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7432 7433 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7434 panic("SELinux: Unable to register AVC netcache callback\n"); 7435 7436 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7437 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7438 7439 if (selinux_enforcing_boot) 7440 pr_debug("SELinux: Starting in enforcing mode\n"); 7441 else 7442 pr_debug("SELinux: Starting in permissive mode\n"); 7443 7444 fs_validate_description("selinux", selinux_fs_parameters); 7445 7446 return 0; 7447 } 7448 7449 static void delayed_superblock_init(struct super_block *sb, void *unused) 7450 { 7451 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7452 } 7453 7454 void selinux_complete_init(void) 7455 { 7456 pr_debug("SELinux: Completing initialization.\n"); 7457 7458 /* Set up any superblocks initialized prior to the policy load. */ 7459 pr_debug("SELinux: Setting up existing superblocks.\n"); 7460 iterate_supers(delayed_superblock_init, NULL); 7461 } 7462 7463 /* SELinux requires early initialization in order to label 7464 all processes and objects when they are created. */ 7465 DEFINE_LSM(selinux) = { 7466 .name = "selinux", 7467 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7468 .enabled = &selinux_enabled_boot, 7469 .blobs = &selinux_blob_sizes, 7470 .init = selinux_init, 7471 }; 7472 7473 #if defined(CONFIG_NETFILTER) 7474 7475 static const struct nf_hook_ops selinux_nf_ops[] = { 7476 { 7477 .hook = selinux_ipv4_postroute, 7478 .pf = NFPROTO_IPV4, 7479 .hooknum = NF_INET_POST_ROUTING, 7480 .priority = NF_IP_PRI_SELINUX_LAST, 7481 }, 7482 { 7483 .hook = selinux_ipv4_forward, 7484 .pf = NFPROTO_IPV4, 7485 .hooknum = NF_INET_FORWARD, 7486 .priority = NF_IP_PRI_SELINUX_FIRST, 7487 }, 7488 { 7489 .hook = selinux_ipv4_output, 7490 .pf = NFPROTO_IPV4, 7491 .hooknum = NF_INET_LOCAL_OUT, 7492 .priority = NF_IP_PRI_SELINUX_FIRST, 7493 }, 7494 #if IS_ENABLED(CONFIG_IPV6) 7495 { 7496 .hook = selinux_ipv6_postroute, 7497 .pf = NFPROTO_IPV6, 7498 .hooknum = NF_INET_POST_ROUTING, 7499 .priority = NF_IP6_PRI_SELINUX_LAST, 7500 }, 7501 { 7502 .hook = selinux_ipv6_forward, 7503 .pf = NFPROTO_IPV6, 7504 .hooknum = NF_INET_FORWARD, 7505 .priority = NF_IP6_PRI_SELINUX_FIRST, 7506 }, 7507 { 7508 .hook = selinux_ipv6_output, 7509 .pf = NFPROTO_IPV6, 7510 .hooknum = NF_INET_LOCAL_OUT, 7511 .priority = NF_IP6_PRI_SELINUX_FIRST, 7512 }, 7513 #endif /* IPV6 */ 7514 }; 7515 7516 static int __net_init selinux_nf_register(struct net *net) 7517 { 7518 return nf_register_net_hooks(net, selinux_nf_ops, 7519 ARRAY_SIZE(selinux_nf_ops)); 7520 } 7521 7522 static void __net_exit selinux_nf_unregister(struct net *net) 7523 { 7524 nf_unregister_net_hooks(net, selinux_nf_ops, 7525 ARRAY_SIZE(selinux_nf_ops)); 7526 } 7527 7528 static struct pernet_operations selinux_net_ops = { 7529 .init = selinux_nf_register, 7530 .exit = selinux_nf_unregister, 7531 }; 7532 7533 static int __init selinux_nf_ip_init(void) 7534 { 7535 int err; 7536 7537 if (!selinux_enabled_boot) 7538 return 0; 7539 7540 pr_debug("SELinux: Registering netfilter hooks\n"); 7541 7542 err = register_pernet_subsys(&selinux_net_ops); 7543 if (err) 7544 panic("SELinux: register_pernet_subsys: error %d\n", err); 7545 7546 return 0; 7547 } 7548 __initcall(selinux_nf_ip_init); 7549 7550 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7551 static void selinux_nf_ip_exit(void) 7552 { 7553 pr_debug("SELinux: Unregistering netfilter hooks\n"); 7554 7555 unregister_pernet_subsys(&selinux_net_ops); 7556 } 7557 #endif 7558 7559 #else /* CONFIG_NETFILTER */ 7560 7561 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7562 #define selinux_nf_ip_exit() 7563 #endif 7564 7565 #endif /* CONFIG_NETFILTER */ 7566 7567 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7568 int selinux_disable(struct selinux_state *state) 7569 { 7570 if (selinux_initialized(state)) { 7571 /* Not permitted after initial policy load. */ 7572 return -EINVAL; 7573 } 7574 7575 if (selinux_disabled(state)) { 7576 /* Only do this once. */ 7577 return -EINVAL; 7578 } 7579 7580 selinux_mark_disabled(state); 7581 7582 pr_info("SELinux: Disabled at runtime.\n"); 7583 7584 /* 7585 * Unregister netfilter hooks. 7586 * Must be done before security_delete_hooks() to avoid breaking 7587 * runtime disable. 7588 */ 7589 selinux_nf_ip_exit(); 7590 7591 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 7592 7593 /* Try to destroy the avc node cache */ 7594 avc_disable(); 7595 7596 /* Unregister selinuxfs. */ 7597 exit_sel_fs(); 7598 7599 return 0; 7600 } 7601 #endif 7602