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