1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Security-Enhanced Linux (SELinux) security module 4 * 5 * This file contains the SELinux hook function implementations. 6 * 7 * Authors: Stephen Smalley, <stephen.smalley.work@gmail.com> 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 <uapi/linux/shm.h> 89 #include <linux/bpf.h> 90 #include <linux/kernfs.h> 91 #include <linux/stringhash.h> /* for hashlen_string() */ 92 #include <uapi/linux/mount.h> 93 #include <linux/fsnotify.h> 94 #include <linux/fanotify.h> 95 #include <linux/io_uring/cmd.h> 96 #include <uapi/linux/lsm.h> 97 98 #include "avc.h" 99 #include "objsec.h" 100 #include "netif.h" 101 #include "netnode.h" 102 #include "netport.h" 103 #include "ibpkey.h" 104 #include "xfrm.h" 105 #include "netlabel.h" 106 #include "audit.h" 107 #include "avc_ss.h" 108 109 #define SELINUX_INODE_INIT_XATTRS 1 110 111 struct selinux_state selinux_state; 112 113 /* SECMARK reference count */ 114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 115 116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 117 static int selinux_enforcing_boot __initdata; 118 119 static int __init enforcing_setup(char *str) 120 { 121 unsigned long enforcing; 122 if (!kstrtoul(str, 0, &enforcing)) 123 selinux_enforcing_boot = enforcing ? 1 : 0; 124 return 1; 125 } 126 __setup("enforcing=", enforcing_setup); 127 #else 128 #define selinux_enforcing_boot 1 129 #endif 130 131 int selinux_enabled_boot __initdata = 1; 132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 133 static int __init selinux_enabled_setup(char *str) 134 { 135 unsigned long enabled; 136 if (!kstrtoul(str, 0, &enabled)) 137 selinux_enabled_boot = enabled ? 1 : 0; 138 return 1; 139 } 140 __setup("selinux=", selinux_enabled_setup); 141 #endif 142 143 static int __init checkreqprot_setup(char *str) 144 { 145 unsigned long checkreqprot; 146 147 if (!kstrtoul(str, 0, &checkreqprot)) { 148 if (checkreqprot) 149 pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\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 static void __ad_net_init(struct common_audit_data *ad, 232 struct lsm_network_audit *net, 233 int ifindex, struct sock *sk, u16 family) 234 { 235 ad->type = LSM_AUDIT_DATA_NET; 236 ad->u.net = net; 237 net->netif = ifindex; 238 net->sk = sk; 239 net->family = family; 240 } 241 242 static void ad_net_init_from_sk(struct common_audit_data *ad, 243 struct lsm_network_audit *net, 244 struct sock *sk) 245 { 246 __ad_net_init(ad, net, 0, sk, 0); 247 } 248 249 static void ad_net_init_from_iif(struct common_audit_data *ad, 250 struct lsm_network_audit *net, 251 int ifindex, u16 family) 252 { 253 __ad_net_init(ad, net, ifindex, NULL, family); 254 } 255 256 /* 257 * get the objective security ID of a task 258 */ 259 static inline u32 task_sid_obj(const struct task_struct *task) 260 { 261 u32 sid; 262 263 rcu_read_lock(); 264 sid = cred_sid(__task_cred(task)); 265 rcu_read_unlock(); 266 return sid; 267 } 268 269 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 270 271 /* 272 * Try reloading inode security labels that have been marked as invalid. The 273 * @may_sleep parameter indicates when sleeping and thus reloading labels is 274 * allowed; when set to false, returns -ECHILD when the label is 275 * invalid. The @dentry parameter should be set to a dentry of the inode. 276 */ 277 static int __inode_security_revalidate(struct inode *inode, 278 struct dentry *dentry, 279 bool may_sleep) 280 { 281 struct inode_security_struct *isec = selinux_inode(inode); 282 283 might_sleep_if(may_sleep); 284 285 if (selinux_initialized() && 286 isec->initialized != LABEL_INITIALIZED) { 287 if (!may_sleep) 288 return -ECHILD; 289 290 /* 291 * Try reloading the inode security label. This will fail if 292 * @opt_dentry is NULL and no dentry for this inode can be 293 * found; in that case, continue using the old label. 294 */ 295 inode_doinit_with_dentry(inode, dentry); 296 } 297 return 0; 298 } 299 300 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 301 { 302 return selinux_inode(inode); 303 } 304 305 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 306 { 307 int error; 308 309 error = __inode_security_revalidate(inode, NULL, !rcu); 310 if (error) 311 return ERR_PTR(error); 312 return selinux_inode(inode); 313 } 314 315 /* 316 * Get the security label of an inode. 317 */ 318 static struct inode_security_struct *inode_security(struct inode *inode) 319 { 320 __inode_security_revalidate(inode, NULL, true); 321 return selinux_inode(inode); 322 } 323 324 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 325 { 326 struct inode *inode = d_backing_inode(dentry); 327 328 return selinux_inode(inode); 329 } 330 331 /* 332 * Get the security label of a dentry's backing inode. 333 */ 334 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 335 { 336 struct inode *inode = d_backing_inode(dentry); 337 338 __inode_security_revalidate(inode, dentry, true); 339 return selinux_inode(inode); 340 } 341 342 static void inode_free_security(struct inode *inode) 343 { 344 struct inode_security_struct *isec = selinux_inode(inode); 345 struct superblock_security_struct *sbsec; 346 347 if (!isec) 348 return; 349 sbsec = selinux_superblock(inode->i_sb); 350 /* 351 * As not all inode security structures are in a list, we check for 352 * empty list outside of the lock to make sure that we won't waste 353 * time taking a lock doing nothing. 354 * 355 * The list_del_init() function can be safely called more than once. 356 * It should not be possible for this function to be called with 357 * concurrent list_add(), but for better safety against future changes 358 * in the code, we use list_empty_careful() here. 359 */ 360 if (!list_empty_careful(&isec->list)) { 361 spin_lock(&sbsec->isec_lock); 362 list_del_init(&isec->list); 363 spin_unlock(&sbsec->isec_lock); 364 } 365 } 366 367 struct selinux_mnt_opts { 368 u32 fscontext_sid; 369 u32 context_sid; 370 u32 rootcontext_sid; 371 u32 defcontext_sid; 372 }; 373 374 static void selinux_free_mnt_opts(void *mnt_opts) 375 { 376 kfree(mnt_opts); 377 } 378 379 enum { 380 Opt_error = -1, 381 Opt_context = 0, 382 Opt_defcontext = 1, 383 Opt_fscontext = 2, 384 Opt_rootcontext = 3, 385 Opt_seclabel = 4, 386 }; 387 388 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} 389 static const struct { 390 const char *name; 391 int len; 392 int opt; 393 bool has_arg; 394 } tokens[] = { 395 A(context, true), 396 A(fscontext, true), 397 A(defcontext, true), 398 A(rootcontext, true), 399 A(seclabel, false), 400 }; 401 #undef A 402 403 static int match_opt_prefix(char *s, int l, char **arg) 404 { 405 int i; 406 407 for (i = 0; i < ARRAY_SIZE(tokens); i++) { 408 size_t len = tokens[i].len; 409 if (len > l || memcmp(s, tokens[i].name, len)) 410 continue; 411 if (tokens[i].has_arg) { 412 if (len == l || s[len] != '=') 413 continue; 414 *arg = s + len + 1; 415 } else if (len != l) 416 continue; 417 return tokens[i].opt; 418 } 419 return Opt_error; 420 } 421 422 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 423 424 static int may_context_mount_sb_relabel(u32 sid, 425 struct superblock_security_struct *sbsec, 426 const struct cred *cred) 427 { 428 const struct task_security_struct *tsec = selinux_cred(cred); 429 int rc; 430 431 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 432 FILESYSTEM__RELABELFROM, NULL); 433 if (rc) 434 return rc; 435 436 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 437 FILESYSTEM__RELABELTO, NULL); 438 return rc; 439 } 440 441 static int may_context_mount_inode_relabel(u32 sid, 442 struct superblock_security_struct *sbsec, 443 const struct cred *cred) 444 { 445 const struct task_security_struct *tsec = selinux_cred(cred); 446 int rc; 447 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 448 FILESYSTEM__RELABELFROM, NULL); 449 if (rc) 450 return rc; 451 452 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 453 FILESYSTEM__ASSOCIATE, NULL); 454 return rc; 455 } 456 457 static int selinux_is_genfs_special_handling(struct super_block *sb) 458 { 459 /* Special handling. Genfs but also in-core setxattr handler */ 460 return !strcmp(sb->s_type->name, "sysfs") || 461 !strcmp(sb->s_type->name, "pstore") || 462 !strcmp(sb->s_type->name, "debugfs") || 463 !strcmp(sb->s_type->name, "tracefs") || 464 !strcmp(sb->s_type->name, "rootfs") || 465 (selinux_policycap_cgroupseclabel() && 466 (!strcmp(sb->s_type->name, "cgroup") || 467 !strcmp(sb->s_type->name, "cgroup2"))); 468 } 469 470 static int selinux_is_sblabel_mnt(struct super_block *sb) 471 { 472 struct superblock_security_struct *sbsec = selinux_superblock(sb); 473 474 /* 475 * IMPORTANT: Double-check logic in this function when adding a new 476 * SECURITY_FS_USE_* definition! 477 */ 478 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); 479 480 switch (sbsec->behavior) { 481 case SECURITY_FS_USE_XATTR: 482 case SECURITY_FS_USE_TRANS: 483 case SECURITY_FS_USE_TASK: 484 case SECURITY_FS_USE_NATIVE: 485 return 1; 486 487 case SECURITY_FS_USE_GENFS: 488 return selinux_is_genfs_special_handling(sb); 489 490 /* Never allow relabeling on context mounts */ 491 case SECURITY_FS_USE_MNTPOINT: 492 case SECURITY_FS_USE_NONE: 493 default: 494 return 0; 495 } 496 } 497 498 static int sb_check_xattr_support(struct super_block *sb) 499 { 500 struct superblock_security_struct *sbsec = selinux_superblock(sb); 501 struct dentry *root = sb->s_root; 502 struct inode *root_inode = d_backing_inode(root); 503 u32 sid; 504 int rc; 505 506 /* 507 * Make sure that the xattr handler exists and that no 508 * error other than -ENODATA is returned by getxattr on 509 * the root directory. -ENODATA is ok, as this may be 510 * the first boot of the SELinux kernel before we have 511 * assigned xattr values to the filesystem. 512 */ 513 if (!(root_inode->i_opflags & IOP_XATTR)) { 514 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", 515 sb->s_id, sb->s_type->name); 516 goto fallback; 517 } 518 519 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 520 if (rc < 0 && rc != -ENODATA) { 521 if (rc == -EOPNOTSUPP) { 522 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", 523 sb->s_id, sb->s_type->name); 524 goto fallback; 525 } else { 526 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", 527 sb->s_id, sb->s_type->name, -rc); 528 return rc; 529 } 530 } 531 return 0; 532 533 fallback: 534 /* No xattr support - try to fallback to genfs if possible. */ 535 rc = security_genfs_sid(sb->s_type->name, "/", 536 SECCLASS_DIR, &sid); 537 if (rc) 538 return -EOPNOTSUPP; 539 540 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", 541 sb->s_id, sb->s_type->name); 542 sbsec->behavior = SECURITY_FS_USE_GENFS; 543 sbsec->sid = sid; 544 return 0; 545 } 546 547 static int sb_finish_set_opts(struct super_block *sb) 548 { 549 struct superblock_security_struct *sbsec = selinux_superblock(sb); 550 struct dentry *root = sb->s_root; 551 struct inode *root_inode = d_backing_inode(root); 552 int rc = 0; 553 554 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 555 rc = sb_check_xattr_support(sb); 556 if (rc) 557 return rc; 558 } 559 560 sbsec->flags |= SE_SBINITIALIZED; 561 562 /* 563 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 564 * leave the flag untouched because sb_clone_mnt_opts might be handing 565 * us a superblock that needs the flag to be cleared. 566 */ 567 if (selinux_is_sblabel_mnt(sb)) 568 sbsec->flags |= SBLABEL_MNT; 569 else 570 sbsec->flags &= ~SBLABEL_MNT; 571 572 /* Initialize the root inode. */ 573 rc = inode_doinit_with_dentry(root_inode, root); 574 575 /* Initialize any other inodes associated with the superblock, e.g. 576 inodes created prior to initial policy load or inodes created 577 during get_sb by a pseudo filesystem that directly 578 populates itself. */ 579 spin_lock(&sbsec->isec_lock); 580 while (!list_empty(&sbsec->isec_head)) { 581 struct inode_security_struct *isec = 582 list_first_entry(&sbsec->isec_head, 583 struct inode_security_struct, list); 584 struct inode *inode = isec->inode; 585 list_del_init(&isec->list); 586 spin_unlock(&sbsec->isec_lock); 587 inode = igrab(inode); 588 if (inode) { 589 if (!IS_PRIVATE(inode)) 590 inode_doinit_with_dentry(inode, NULL); 591 iput(inode); 592 } 593 spin_lock(&sbsec->isec_lock); 594 } 595 spin_unlock(&sbsec->isec_lock); 596 return rc; 597 } 598 599 static int bad_option(struct superblock_security_struct *sbsec, char flag, 600 u32 old_sid, u32 new_sid) 601 { 602 char mnt_flags = sbsec->flags & SE_MNTMASK; 603 604 /* check if the old mount command had the same options */ 605 if (sbsec->flags & SE_SBINITIALIZED) 606 if (!(sbsec->flags & flag) || 607 (old_sid != new_sid)) 608 return 1; 609 610 /* check if we were passed the same options twice, 611 * aka someone passed context=a,context=b 612 */ 613 if (!(sbsec->flags & SE_SBINITIALIZED)) 614 if (mnt_flags & flag) 615 return 1; 616 return 0; 617 } 618 619 /* 620 * Allow filesystems with binary mount data to explicitly set mount point 621 * labeling information. 622 */ 623 static int selinux_set_mnt_opts(struct super_block *sb, 624 void *mnt_opts, 625 unsigned long kern_flags, 626 unsigned long *set_kern_flags) 627 { 628 const struct cred *cred = current_cred(); 629 struct superblock_security_struct *sbsec = selinux_superblock(sb); 630 struct dentry *root = sb->s_root; 631 struct selinux_mnt_opts *opts = mnt_opts; 632 struct inode_security_struct *root_isec; 633 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 634 u32 defcontext_sid = 0; 635 int rc = 0; 636 637 /* 638 * Specifying internal flags without providing a place to 639 * place the results is not allowed 640 */ 641 if (kern_flags && !set_kern_flags) 642 return -EINVAL; 643 644 mutex_lock(&sbsec->lock); 645 646 if (!selinux_initialized()) { 647 if (!opts) { 648 /* Defer initialization until selinux_complete_init, 649 after the initial policy is loaded and the security 650 server is ready to handle calls. */ 651 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 652 sbsec->flags |= SE_SBNATIVE; 653 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 654 } 655 goto out; 656 } 657 rc = -EINVAL; 658 pr_warn("SELinux: Unable to set superblock options " 659 "before the security server is initialized\n"); 660 goto out; 661 } 662 663 /* 664 * Binary mount data FS will come through this function twice. Once 665 * from an explicit call and once from the generic calls from the vfs. 666 * Since the generic VFS calls will not contain any security mount data 667 * we need to skip the double mount verification. 668 * 669 * This does open a hole in which we will not notice if the first 670 * mount using this sb set explicit options and a second mount using 671 * this sb does not set any security options. (The first options 672 * will be used for both mounts) 673 */ 674 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 675 && !opts) 676 goto out; 677 678 root_isec = backing_inode_security_novalidate(root); 679 680 /* 681 * parse the mount options, check if they are valid sids. 682 * also check if someone is trying to mount the same sb more 683 * than once with different security options. 684 */ 685 if (opts) { 686 if (opts->fscontext_sid) { 687 fscontext_sid = opts->fscontext_sid; 688 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 689 fscontext_sid)) 690 goto out_double_mount; 691 sbsec->flags |= FSCONTEXT_MNT; 692 } 693 if (opts->context_sid) { 694 context_sid = opts->context_sid; 695 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 696 context_sid)) 697 goto out_double_mount; 698 sbsec->flags |= CONTEXT_MNT; 699 } 700 if (opts->rootcontext_sid) { 701 rootcontext_sid = opts->rootcontext_sid; 702 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 703 rootcontext_sid)) 704 goto out_double_mount; 705 sbsec->flags |= ROOTCONTEXT_MNT; 706 } 707 if (opts->defcontext_sid) { 708 defcontext_sid = opts->defcontext_sid; 709 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 710 defcontext_sid)) 711 goto out_double_mount; 712 sbsec->flags |= DEFCONTEXT_MNT; 713 } 714 } 715 716 if (sbsec->flags & SE_SBINITIALIZED) { 717 /* previously mounted with options, but not on this attempt? */ 718 if ((sbsec->flags & SE_MNTMASK) && !opts) 719 goto out_double_mount; 720 rc = 0; 721 goto out; 722 } 723 724 if (strcmp(sb->s_type->name, "proc") == 0) 725 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 726 727 if (!strcmp(sb->s_type->name, "debugfs") || 728 !strcmp(sb->s_type->name, "tracefs") || 729 !strcmp(sb->s_type->name, "binder") || 730 !strcmp(sb->s_type->name, "bpf") || 731 !strcmp(sb->s_type->name, "pstore") || 732 !strcmp(sb->s_type->name, "securityfs")) 733 sbsec->flags |= SE_SBGENFS; 734 735 if (!strcmp(sb->s_type->name, "sysfs") || 736 !strcmp(sb->s_type->name, "cgroup") || 737 !strcmp(sb->s_type->name, "cgroup2")) 738 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; 739 740 if (!sbsec->behavior) { 741 /* 742 * Determine the labeling behavior to use for this 743 * filesystem type. 744 */ 745 rc = security_fs_use(sb); 746 if (rc) { 747 pr_warn("%s: security_fs_use(%s) returned %d\n", 748 __func__, sb->s_type->name, rc); 749 goto out; 750 } 751 } 752 753 /* 754 * If this is a user namespace mount and the filesystem type is not 755 * explicitly whitelisted, then no contexts are allowed on the command 756 * line and security labels must be ignored. 757 */ 758 if (sb->s_user_ns != &init_user_ns && 759 strcmp(sb->s_type->name, "tmpfs") && 760 strcmp(sb->s_type->name, "ramfs") && 761 strcmp(sb->s_type->name, "devpts") && 762 strcmp(sb->s_type->name, "overlay")) { 763 if (context_sid || fscontext_sid || rootcontext_sid || 764 defcontext_sid) { 765 rc = -EACCES; 766 goto out; 767 } 768 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 769 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 770 rc = security_transition_sid(current_sid(), 771 current_sid(), 772 SECCLASS_FILE, NULL, 773 &sbsec->mntpoint_sid); 774 if (rc) 775 goto out; 776 } 777 goto out_set_opts; 778 } 779 780 /* sets the context of the superblock for the fs being mounted. */ 781 if (fscontext_sid) { 782 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 783 if (rc) 784 goto out; 785 786 sbsec->sid = fscontext_sid; 787 } 788 789 /* 790 * Switch to using mount point labeling behavior. 791 * sets the label used on all file below the mountpoint, and will set 792 * the superblock context if not already set. 793 */ 794 if (sbsec->flags & SE_SBNATIVE) { 795 /* 796 * This means we are initializing a superblock that has been 797 * mounted before the SELinux was initialized and the 798 * filesystem requested native labeling. We had already 799 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags 800 * in the original mount attempt, so now we just need to set 801 * the SECURITY_FS_USE_NATIVE behavior. 802 */ 803 sbsec->behavior = SECURITY_FS_USE_NATIVE; 804 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 805 sbsec->behavior = SECURITY_FS_USE_NATIVE; 806 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 807 } 808 809 if (context_sid) { 810 if (!fscontext_sid) { 811 rc = may_context_mount_sb_relabel(context_sid, sbsec, 812 cred); 813 if (rc) 814 goto out; 815 sbsec->sid = context_sid; 816 } else { 817 rc = may_context_mount_inode_relabel(context_sid, sbsec, 818 cred); 819 if (rc) 820 goto out; 821 } 822 if (!rootcontext_sid) 823 rootcontext_sid = context_sid; 824 825 sbsec->mntpoint_sid = context_sid; 826 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 827 } 828 829 if (rootcontext_sid) { 830 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 831 cred); 832 if (rc) 833 goto out; 834 835 root_isec->sid = rootcontext_sid; 836 root_isec->initialized = LABEL_INITIALIZED; 837 } 838 839 if (defcontext_sid) { 840 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 841 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 842 rc = -EINVAL; 843 pr_warn("SELinux: defcontext option is " 844 "invalid for this filesystem type\n"); 845 goto out; 846 } 847 848 if (defcontext_sid != sbsec->def_sid) { 849 rc = may_context_mount_inode_relabel(defcontext_sid, 850 sbsec, cred); 851 if (rc) 852 goto out; 853 } 854 855 sbsec->def_sid = defcontext_sid; 856 } 857 858 out_set_opts: 859 rc = sb_finish_set_opts(sb); 860 out: 861 mutex_unlock(&sbsec->lock); 862 return rc; 863 out_double_mount: 864 rc = -EINVAL; 865 pr_warn("SELinux: mount invalid. Same superblock, different " 866 "security settings for (dev %s, type %s)\n", sb->s_id, 867 sb->s_type->name); 868 goto out; 869 } 870 871 static int selinux_cmp_sb_context(const struct super_block *oldsb, 872 const struct super_block *newsb) 873 { 874 struct superblock_security_struct *old = selinux_superblock(oldsb); 875 struct superblock_security_struct *new = selinux_superblock(newsb); 876 char oldflags = old->flags & SE_MNTMASK; 877 char newflags = new->flags & SE_MNTMASK; 878 879 if (oldflags != newflags) 880 goto mismatch; 881 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 882 goto mismatch; 883 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 884 goto mismatch; 885 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 886 goto mismatch; 887 if (oldflags & ROOTCONTEXT_MNT) { 888 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 889 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 890 if (oldroot->sid != newroot->sid) 891 goto mismatch; 892 } 893 return 0; 894 mismatch: 895 pr_warn("SELinux: mount invalid. Same superblock, " 896 "different security settings for (dev %s, " 897 "type %s)\n", newsb->s_id, newsb->s_type->name); 898 return -EBUSY; 899 } 900 901 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 902 struct super_block *newsb, 903 unsigned long kern_flags, 904 unsigned long *set_kern_flags) 905 { 906 int rc = 0; 907 const struct superblock_security_struct *oldsbsec = 908 selinux_superblock(oldsb); 909 struct superblock_security_struct *newsbsec = selinux_superblock(newsb); 910 911 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 912 int set_context = (oldsbsec->flags & CONTEXT_MNT); 913 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 914 915 /* 916 * Specifying internal flags without providing a place to 917 * place the results is not allowed. 918 */ 919 if (kern_flags && !set_kern_flags) 920 return -EINVAL; 921 922 mutex_lock(&newsbsec->lock); 923 924 /* 925 * if the parent was able to be mounted it clearly had no special lsm 926 * mount options. thus we can safely deal with this superblock later 927 */ 928 if (!selinux_initialized()) { 929 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { 930 newsbsec->flags |= SE_SBNATIVE; 931 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 932 } 933 goto out; 934 } 935 936 /* how can we clone if the old one wasn't set up?? */ 937 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 938 939 /* if fs is reusing a sb, make sure that the contexts match */ 940 if (newsbsec->flags & SE_SBINITIALIZED) { 941 mutex_unlock(&newsbsec->lock); 942 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) 943 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 944 return selinux_cmp_sb_context(oldsb, newsb); 945 } 946 947 newsbsec->flags = oldsbsec->flags; 948 949 newsbsec->sid = oldsbsec->sid; 950 newsbsec->def_sid = oldsbsec->def_sid; 951 newsbsec->behavior = oldsbsec->behavior; 952 953 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 954 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 955 rc = security_fs_use(newsb); 956 if (rc) 957 goto out; 958 } 959 960 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 961 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 962 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 963 } 964 965 if (set_context) { 966 u32 sid = oldsbsec->mntpoint_sid; 967 968 if (!set_fscontext) 969 newsbsec->sid = sid; 970 if (!set_rootcontext) { 971 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 972 newisec->sid = sid; 973 } 974 newsbsec->mntpoint_sid = sid; 975 } 976 if (set_rootcontext) { 977 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 978 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 979 980 newisec->sid = oldisec->sid; 981 } 982 983 sb_finish_set_opts(newsb); 984 out: 985 mutex_unlock(&newsbsec->lock); 986 return rc; 987 } 988 989 /* 990 * NOTE: the caller is responsible for freeing the memory even if on error. 991 */ 992 static int selinux_add_opt(int token, const char *s, void **mnt_opts) 993 { 994 struct selinux_mnt_opts *opts = *mnt_opts; 995 u32 *dst_sid; 996 int rc; 997 998 if (token == Opt_seclabel) 999 /* eaten and completely ignored */ 1000 return 0; 1001 if (!s) 1002 return -EINVAL; 1003 1004 if (!selinux_initialized()) { 1005 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); 1006 return -EINVAL; 1007 } 1008 1009 if (!opts) { 1010 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 1011 if (!opts) 1012 return -ENOMEM; 1013 *mnt_opts = opts; 1014 } 1015 1016 switch (token) { 1017 case Opt_context: 1018 if (opts->context_sid || opts->defcontext_sid) 1019 goto err; 1020 dst_sid = &opts->context_sid; 1021 break; 1022 case Opt_fscontext: 1023 if (opts->fscontext_sid) 1024 goto err; 1025 dst_sid = &opts->fscontext_sid; 1026 break; 1027 case Opt_rootcontext: 1028 if (opts->rootcontext_sid) 1029 goto err; 1030 dst_sid = &opts->rootcontext_sid; 1031 break; 1032 case Opt_defcontext: 1033 if (opts->context_sid || opts->defcontext_sid) 1034 goto err; 1035 dst_sid = &opts->defcontext_sid; 1036 break; 1037 default: 1038 WARN_ON(1); 1039 return -EINVAL; 1040 } 1041 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); 1042 if (rc) 1043 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", 1044 s, rc); 1045 return rc; 1046 1047 err: 1048 pr_warn(SEL_MOUNT_FAIL_MSG); 1049 return -EINVAL; 1050 } 1051 1052 static int show_sid(struct seq_file *m, u32 sid) 1053 { 1054 char *context = NULL; 1055 u32 len; 1056 int rc; 1057 1058 rc = security_sid_to_context(sid, &context, &len); 1059 if (!rc) { 1060 bool has_comma = strchr(context, ','); 1061 1062 seq_putc(m, '='); 1063 if (has_comma) 1064 seq_putc(m, '\"'); 1065 seq_escape(m, context, "\"\n\\"); 1066 if (has_comma) 1067 seq_putc(m, '\"'); 1068 } 1069 kfree(context); 1070 return rc; 1071 } 1072 1073 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1074 { 1075 struct superblock_security_struct *sbsec = selinux_superblock(sb); 1076 int rc; 1077 1078 if (!(sbsec->flags & SE_SBINITIALIZED)) 1079 return 0; 1080 1081 if (!selinux_initialized()) 1082 return 0; 1083 1084 if (sbsec->flags & FSCONTEXT_MNT) { 1085 seq_putc(m, ','); 1086 seq_puts(m, FSCONTEXT_STR); 1087 rc = show_sid(m, sbsec->sid); 1088 if (rc) 1089 return rc; 1090 } 1091 if (sbsec->flags & CONTEXT_MNT) { 1092 seq_putc(m, ','); 1093 seq_puts(m, CONTEXT_STR); 1094 rc = show_sid(m, sbsec->mntpoint_sid); 1095 if (rc) 1096 return rc; 1097 } 1098 if (sbsec->flags & DEFCONTEXT_MNT) { 1099 seq_putc(m, ','); 1100 seq_puts(m, DEFCONTEXT_STR); 1101 rc = show_sid(m, sbsec->def_sid); 1102 if (rc) 1103 return rc; 1104 } 1105 if (sbsec->flags & ROOTCONTEXT_MNT) { 1106 struct dentry *root = sb->s_root; 1107 struct inode_security_struct *isec = backing_inode_security(root); 1108 seq_putc(m, ','); 1109 seq_puts(m, ROOTCONTEXT_STR); 1110 rc = show_sid(m, isec->sid); 1111 if (rc) 1112 return rc; 1113 } 1114 if (sbsec->flags & SBLABEL_MNT) { 1115 seq_putc(m, ','); 1116 seq_puts(m, SECLABEL_STR); 1117 } 1118 return 0; 1119 } 1120 1121 static inline u16 inode_mode_to_security_class(umode_t mode) 1122 { 1123 switch (mode & S_IFMT) { 1124 case S_IFSOCK: 1125 return SECCLASS_SOCK_FILE; 1126 case S_IFLNK: 1127 return SECCLASS_LNK_FILE; 1128 case S_IFREG: 1129 return SECCLASS_FILE; 1130 case S_IFBLK: 1131 return SECCLASS_BLK_FILE; 1132 case S_IFDIR: 1133 return SECCLASS_DIR; 1134 case S_IFCHR: 1135 return SECCLASS_CHR_FILE; 1136 case S_IFIFO: 1137 return SECCLASS_FIFO_FILE; 1138 1139 } 1140 1141 return SECCLASS_FILE; 1142 } 1143 1144 static inline int default_protocol_stream(int protocol) 1145 { 1146 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || 1147 protocol == IPPROTO_MPTCP); 1148 } 1149 1150 static inline int default_protocol_dgram(int protocol) 1151 { 1152 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1153 } 1154 1155 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1156 { 1157 bool extsockclass = selinux_policycap_extsockclass(); 1158 1159 switch (family) { 1160 case PF_UNIX: 1161 switch (type) { 1162 case SOCK_STREAM: 1163 case SOCK_SEQPACKET: 1164 return SECCLASS_UNIX_STREAM_SOCKET; 1165 case SOCK_DGRAM: 1166 case SOCK_RAW: 1167 return SECCLASS_UNIX_DGRAM_SOCKET; 1168 } 1169 break; 1170 case PF_INET: 1171 case PF_INET6: 1172 switch (type) { 1173 case SOCK_STREAM: 1174 case SOCK_SEQPACKET: 1175 if (default_protocol_stream(protocol)) 1176 return SECCLASS_TCP_SOCKET; 1177 else if (extsockclass && protocol == IPPROTO_SCTP) 1178 return SECCLASS_SCTP_SOCKET; 1179 else 1180 return SECCLASS_RAWIP_SOCKET; 1181 case SOCK_DGRAM: 1182 if (default_protocol_dgram(protocol)) 1183 return SECCLASS_UDP_SOCKET; 1184 else if (extsockclass && (protocol == IPPROTO_ICMP || 1185 protocol == IPPROTO_ICMPV6)) 1186 return SECCLASS_ICMP_SOCKET; 1187 else 1188 return SECCLASS_RAWIP_SOCKET; 1189 case SOCK_DCCP: 1190 return SECCLASS_DCCP_SOCKET; 1191 default: 1192 return SECCLASS_RAWIP_SOCKET; 1193 } 1194 break; 1195 case PF_NETLINK: 1196 switch (protocol) { 1197 case NETLINK_ROUTE: 1198 return SECCLASS_NETLINK_ROUTE_SOCKET; 1199 case NETLINK_SOCK_DIAG: 1200 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1201 case NETLINK_NFLOG: 1202 return SECCLASS_NETLINK_NFLOG_SOCKET; 1203 case NETLINK_XFRM: 1204 return SECCLASS_NETLINK_XFRM_SOCKET; 1205 case NETLINK_SELINUX: 1206 return SECCLASS_NETLINK_SELINUX_SOCKET; 1207 case NETLINK_ISCSI: 1208 return SECCLASS_NETLINK_ISCSI_SOCKET; 1209 case NETLINK_AUDIT: 1210 return SECCLASS_NETLINK_AUDIT_SOCKET; 1211 case NETLINK_FIB_LOOKUP: 1212 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1213 case NETLINK_CONNECTOR: 1214 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1215 case NETLINK_NETFILTER: 1216 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1217 case NETLINK_DNRTMSG: 1218 return SECCLASS_NETLINK_DNRT_SOCKET; 1219 case NETLINK_KOBJECT_UEVENT: 1220 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1221 case NETLINK_GENERIC: 1222 return SECCLASS_NETLINK_GENERIC_SOCKET; 1223 case NETLINK_SCSITRANSPORT: 1224 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1225 case NETLINK_RDMA: 1226 return SECCLASS_NETLINK_RDMA_SOCKET; 1227 case NETLINK_CRYPTO: 1228 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1229 default: 1230 return SECCLASS_NETLINK_SOCKET; 1231 } 1232 case PF_PACKET: 1233 return SECCLASS_PACKET_SOCKET; 1234 case PF_KEY: 1235 return SECCLASS_KEY_SOCKET; 1236 case PF_APPLETALK: 1237 return SECCLASS_APPLETALK_SOCKET; 1238 } 1239 1240 if (extsockclass) { 1241 switch (family) { 1242 case PF_AX25: 1243 return SECCLASS_AX25_SOCKET; 1244 case PF_IPX: 1245 return SECCLASS_IPX_SOCKET; 1246 case PF_NETROM: 1247 return SECCLASS_NETROM_SOCKET; 1248 case PF_ATMPVC: 1249 return SECCLASS_ATMPVC_SOCKET; 1250 case PF_X25: 1251 return SECCLASS_X25_SOCKET; 1252 case PF_ROSE: 1253 return SECCLASS_ROSE_SOCKET; 1254 case PF_DECnet: 1255 return SECCLASS_DECNET_SOCKET; 1256 case PF_ATMSVC: 1257 return SECCLASS_ATMSVC_SOCKET; 1258 case PF_RDS: 1259 return SECCLASS_RDS_SOCKET; 1260 case PF_IRDA: 1261 return SECCLASS_IRDA_SOCKET; 1262 case PF_PPPOX: 1263 return SECCLASS_PPPOX_SOCKET; 1264 case PF_LLC: 1265 return SECCLASS_LLC_SOCKET; 1266 case PF_CAN: 1267 return SECCLASS_CAN_SOCKET; 1268 case PF_TIPC: 1269 return SECCLASS_TIPC_SOCKET; 1270 case PF_BLUETOOTH: 1271 return SECCLASS_BLUETOOTH_SOCKET; 1272 case PF_IUCV: 1273 return SECCLASS_IUCV_SOCKET; 1274 case PF_RXRPC: 1275 return SECCLASS_RXRPC_SOCKET; 1276 case PF_ISDN: 1277 return SECCLASS_ISDN_SOCKET; 1278 case PF_PHONET: 1279 return SECCLASS_PHONET_SOCKET; 1280 case PF_IEEE802154: 1281 return SECCLASS_IEEE802154_SOCKET; 1282 case PF_CAIF: 1283 return SECCLASS_CAIF_SOCKET; 1284 case PF_ALG: 1285 return SECCLASS_ALG_SOCKET; 1286 case PF_NFC: 1287 return SECCLASS_NFC_SOCKET; 1288 case PF_VSOCK: 1289 return SECCLASS_VSOCK_SOCKET; 1290 case PF_KCM: 1291 return SECCLASS_KCM_SOCKET; 1292 case PF_QIPCRTR: 1293 return SECCLASS_QIPCRTR_SOCKET; 1294 case PF_SMC: 1295 return SECCLASS_SMC_SOCKET; 1296 case PF_XDP: 1297 return SECCLASS_XDP_SOCKET; 1298 case PF_MCTP: 1299 return SECCLASS_MCTP_SOCKET; 1300 #if PF_MAX > 46 1301 #error New address family defined, please update this function. 1302 #endif 1303 } 1304 } 1305 1306 return SECCLASS_SOCKET; 1307 } 1308 1309 static int selinux_genfs_get_sid(struct dentry *dentry, 1310 u16 tclass, 1311 u16 flags, 1312 u32 *sid) 1313 { 1314 int rc; 1315 struct super_block *sb = dentry->d_sb; 1316 char *buffer, *path; 1317 1318 buffer = (char *)__get_free_page(GFP_KERNEL); 1319 if (!buffer) 1320 return -ENOMEM; 1321 1322 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1323 if (IS_ERR(path)) 1324 rc = PTR_ERR(path); 1325 else { 1326 if (flags & SE_SBPROC) { 1327 /* each process gets a /proc/PID/ entry. Strip off the 1328 * PID part to get a valid selinux labeling. 1329 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1330 while (path[1] >= '0' && path[1] <= '9') { 1331 path[1] = '/'; 1332 path++; 1333 } 1334 } 1335 rc = security_genfs_sid(sb->s_type->name, 1336 path, tclass, sid); 1337 if (rc == -ENOENT) { 1338 /* No match in policy, mark as unlabeled. */ 1339 *sid = SECINITSID_UNLABELED; 1340 rc = 0; 1341 } 1342 } 1343 free_page((unsigned long)buffer); 1344 return rc; 1345 } 1346 1347 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, 1348 u32 def_sid, u32 *sid) 1349 { 1350 #define INITCONTEXTLEN 255 1351 char *context; 1352 unsigned int len; 1353 int rc; 1354 1355 len = INITCONTEXTLEN; 1356 context = kmalloc(len + 1, GFP_NOFS); 1357 if (!context) 1358 return -ENOMEM; 1359 1360 context[len] = '\0'; 1361 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1362 if (rc == -ERANGE) { 1363 kfree(context); 1364 1365 /* Need a larger buffer. Query for the right size. */ 1366 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1367 if (rc < 0) 1368 return rc; 1369 1370 len = rc; 1371 context = kmalloc(len + 1, GFP_NOFS); 1372 if (!context) 1373 return -ENOMEM; 1374 1375 context[len] = '\0'; 1376 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, 1377 context, len); 1378 } 1379 if (rc < 0) { 1380 kfree(context); 1381 if (rc != -ENODATA) { 1382 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", 1383 __func__, -rc, inode->i_sb->s_id, inode->i_ino); 1384 return rc; 1385 } 1386 *sid = def_sid; 1387 return 0; 1388 } 1389 1390 rc = security_context_to_sid_default(context, rc, sid, 1391 def_sid, GFP_NOFS); 1392 if (rc) { 1393 char *dev = inode->i_sb->s_id; 1394 unsigned long ino = inode->i_ino; 1395 1396 if (rc == -EINVAL) { 1397 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", 1398 ino, dev, context); 1399 } else { 1400 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", 1401 __func__, context, -rc, dev, ino); 1402 } 1403 } 1404 kfree(context); 1405 return 0; 1406 } 1407 1408 /* The inode's security attributes must be initialized before first use. */ 1409 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1410 { 1411 struct superblock_security_struct *sbsec = NULL; 1412 struct inode_security_struct *isec = selinux_inode(inode); 1413 u32 task_sid, sid = 0; 1414 u16 sclass; 1415 struct dentry *dentry; 1416 int rc = 0; 1417 1418 if (isec->initialized == LABEL_INITIALIZED) 1419 return 0; 1420 1421 spin_lock(&isec->lock); 1422 if (isec->initialized == LABEL_INITIALIZED) 1423 goto out_unlock; 1424 1425 if (isec->sclass == SECCLASS_FILE) 1426 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1427 1428 sbsec = selinux_superblock(inode->i_sb); 1429 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1430 /* Defer initialization until selinux_complete_init, 1431 after the initial policy is loaded and the security 1432 server is ready to handle calls. */ 1433 spin_lock(&sbsec->isec_lock); 1434 if (list_empty(&isec->list)) 1435 list_add(&isec->list, &sbsec->isec_head); 1436 spin_unlock(&sbsec->isec_lock); 1437 goto out_unlock; 1438 } 1439 1440 sclass = isec->sclass; 1441 task_sid = isec->task_sid; 1442 sid = isec->sid; 1443 isec->initialized = LABEL_PENDING; 1444 spin_unlock(&isec->lock); 1445 1446 switch (sbsec->behavior) { 1447 /* 1448 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels 1449 * via xattr when called from delayed_superblock_init(). 1450 */ 1451 case SECURITY_FS_USE_NATIVE: 1452 case SECURITY_FS_USE_XATTR: 1453 if (!(inode->i_opflags & IOP_XATTR)) { 1454 sid = sbsec->def_sid; 1455 break; 1456 } 1457 /* Need a dentry, since the xattr API requires one. 1458 Life would be simpler if we could just pass the inode. */ 1459 if (opt_dentry) { 1460 /* Called from d_instantiate or d_splice_alias. */ 1461 dentry = dget(opt_dentry); 1462 } else { 1463 /* 1464 * Called from selinux_complete_init, try to find a dentry. 1465 * Some filesystems really want a connected one, so try 1466 * that first. We could split SECURITY_FS_USE_XATTR in 1467 * two, depending upon that... 1468 */ 1469 dentry = d_find_alias(inode); 1470 if (!dentry) 1471 dentry = d_find_any_alias(inode); 1472 } 1473 if (!dentry) { 1474 /* 1475 * this is can be hit on boot when a file is accessed 1476 * before the policy is loaded. When we load policy we 1477 * may find inodes that have no dentry on the 1478 * sbsec->isec_head list. No reason to complain as these 1479 * will get fixed up the next time we go through 1480 * inode_doinit with a dentry, before these inodes could 1481 * be used again by userspace. 1482 */ 1483 goto out_invalid; 1484 } 1485 1486 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, 1487 &sid); 1488 dput(dentry); 1489 if (rc) 1490 goto out; 1491 break; 1492 case SECURITY_FS_USE_TASK: 1493 sid = task_sid; 1494 break; 1495 case SECURITY_FS_USE_TRANS: 1496 /* Default to the fs SID. */ 1497 sid = sbsec->sid; 1498 1499 /* Try to obtain a transition SID. */ 1500 rc = security_transition_sid(task_sid, sid, 1501 sclass, NULL, &sid); 1502 if (rc) 1503 goto out; 1504 break; 1505 case SECURITY_FS_USE_MNTPOINT: 1506 sid = sbsec->mntpoint_sid; 1507 break; 1508 default: 1509 /* Default to the fs superblock SID. */ 1510 sid = sbsec->sid; 1511 1512 if ((sbsec->flags & SE_SBGENFS) && 1513 (!S_ISLNK(inode->i_mode) || 1514 selinux_policycap_genfs_seclabel_symlinks())) { 1515 /* We must have a dentry to determine the label on 1516 * procfs inodes */ 1517 if (opt_dentry) { 1518 /* Called from d_instantiate or 1519 * d_splice_alias. */ 1520 dentry = dget(opt_dentry); 1521 } else { 1522 /* Called from selinux_complete_init, try to 1523 * find a dentry. Some filesystems really want 1524 * a connected one, so try that first. 1525 */ 1526 dentry = d_find_alias(inode); 1527 if (!dentry) 1528 dentry = d_find_any_alias(inode); 1529 } 1530 /* 1531 * This can be hit on boot when a file is accessed 1532 * before the policy is loaded. When we load policy we 1533 * may find inodes that have no dentry on the 1534 * sbsec->isec_head list. No reason to complain as 1535 * these will get fixed up the next time we go through 1536 * inode_doinit() with a dentry, before these inodes 1537 * could be used again by userspace. 1538 */ 1539 if (!dentry) 1540 goto out_invalid; 1541 rc = selinux_genfs_get_sid(dentry, sclass, 1542 sbsec->flags, &sid); 1543 if (rc) { 1544 dput(dentry); 1545 goto out; 1546 } 1547 1548 if ((sbsec->flags & SE_SBGENFS_XATTR) && 1549 (inode->i_opflags & IOP_XATTR)) { 1550 rc = inode_doinit_use_xattr(inode, dentry, 1551 sid, &sid); 1552 if (rc) { 1553 dput(dentry); 1554 goto out; 1555 } 1556 } 1557 dput(dentry); 1558 } 1559 break; 1560 } 1561 1562 out: 1563 spin_lock(&isec->lock); 1564 if (isec->initialized == LABEL_PENDING) { 1565 if (rc) { 1566 isec->initialized = LABEL_INVALID; 1567 goto out_unlock; 1568 } 1569 isec->initialized = LABEL_INITIALIZED; 1570 isec->sid = sid; 1571 } 1572 1573 out_unlock: 1574 spin_unlock(&isec->lock); 1575 return rc; 1576 1577 out_invalid: 1578 spin_lock(&isec->lock); 1579 if (isec->initialized == LABEL_PENDING) { 1580 isec->initialized = LABEL_INVALID; 1581 isec->sid = sid; 1582 } 1583 spin_unlock(&isec->lock); 1584 return 0; 1585 } 1586 1587 /* Convert a Linux signal to an access vector. */ 1588 static inline u32 signal_to_av(int sig) 1589 { 1590 u32 perm = 0; 1591 1592 switch (sig) { 1593 case SIGCHLD: 1594 /* Commonly granted from child to parent. */ 1595 perm = PROCESS__SIGCHLD; 1596 break; 1597 case SIGKILL: 1598 /* Cannot be caught or ignored */ 1599 perm = PROCESS__SIGKILL; 1600 break; 1601 case SIGSTOP: 1602 /* Cannot be caught or ignored */ 1603 perm = PROCESS__SIGSTOP; 1604 break; 1605 default: 1606 /* All other signals. */ 1607 perm = PROCESS__SIGNAL; 1608 break; 1609 } 1610 1611 return perm; 1612 } 1613 1614 #if CAP_LAST_CAP > 63 1615 #error Fix SELinux to handle capabilities > 63. 1616 #endif 1617 1618 /* Check whether a task is allowed to use a capability. */ 1619 static int cred_has_capability(const struct cred *cred, 1620 int cap, unsigned int opts, bool initns) 1621 { 1622 struct common_audit_data ad; 1623 struct av_decision avd; 1624 u16 sclass; 1625 u32 sid = cred_sid(cred); 1626 u32 av = CAP_TO_MASK(cap); 1627 int rc; 1628 1629 ad.type = LSM_AUDIT_DATA_CAP; 1630 ad.u.cap = cap; 1631 1632 switch (CAP_TO_INDEX(cap)) { 1633 case 0: 1634 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1635 break; 1636 case 1: 1637 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1638 break; 1639 default: 1640 pr_err("SELinux: out of range capability %d\n", cap); 1641 BUG(); 1642 return -EINVAL; 1643 } 1644 1645 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1646 if (!(opts & CAP_OPT_NOAUDIT)) { 1647 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1648 if (rc2) 1649 return rc2; 1650 } 1651 return rc; 1652 } 1653 1654 /* Check whether a task has a particular permission to an inode. 1655 The 'adp' parameter is optional and allows other audit 1656 data to be passed (e.g. the dentry). */ 1657 static int inode_has_perm(const struct cred *cred, 1658 struct inode *inode, 1659 u32 perms, 1660 struct common_audit_data *adp) 1661 { 1662 struct inode_security_struct *isec; 1663 u32 sid; 1664 1665 if (unlikely(IS_PRIVATE(inode))) 1666 return 0; 1667 1668 sid = cred_sid(cred); 1669 isec = selinux_inode(inode); 1670 1671 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1672 } 1673 1674 /* Same as inode_has_perm, but pass explicit audit data containing 1675 the dentry to help the auditing code to more easily generate the 1676 pathname if needed. */ 1677 static inline int dentry_has_perm(const struct cred *cred, 1678 struct dentry *dentry, 1679 u32 av) 1680 { 1681 struct inode *inode = d_backing_inode(dentry); 1682 struct common_audit_data ad; 1683 1684 ad.type = LSM_AUDIT_DATA_DENTRY; 1685 ad.u.dentry = dentry; 1686 __inode_security_revalidate(inode, dentry, true); 1687 return inode_has_perm(cred, inode, av, &ad); 1688 } 1689 1690 /* Same as inode_has_perm, but pass explicit audit data containing 1691 the path to help the auditing code to more easily generate the 1692 pathname if needed. */ 1693 static inline int path_has_perm(const struct cred *cred, 1694 const struct path *path, 1695 u32 av) 1696 { 1697 struct inode *inode = d_backing_inode(path->dentry); 1698 struct common_audit_data ad; 1699 1700 ad.type = LSM_AUDIT_DATA_PATH; 1701 ad.u.path = *path; 1702 __inode_security_revalidate(inode, path->dentry, true); 1703 return inode_has_perm(cred, inode, av, &ad); 1704 } 1705 1706 /* Same as path_has_perm, but uses the inode from the file struct. */ 1707 static inline int file_path_has_perm(const struct cred *cred, 1708 struct file *file, 1709 u32 av) 1710 { 1711 struct common_audit_data ad; 1712 1713 ad.type = LSM_AUDIT_DATA_FILE; 1714 ad.u.file = file; 1715 return inode_has_perm(cred, file_inode(file), av, &ad); 1716 } 1717 1718 #ifdef CONFIG_BPF_SYSCALL 1719 static int bpf_fd_pass(const struct file *file, u32 sid); 1720 #endif 1721 1722 /* Check whether a task can use an open file descriptor to 1723 access an inode in a given way. Check access to the 1724 descriptor itself, and then use dentry_has_perm to 1725 check a particular permission to the file. 1726 Access to the descriptor is implicitly granted if it 1727 has the same SID as the process. If av is zero, then 1728 access to the file is not checked, e.g. for cases 1729 where only the descriptor is affected like seek. */ 1730 static int file_has_perm(const struct cred *cred, 1731 struct file *file, 1732 u32 av) 1733 { 1734 struct file_security_struct *fsec = selinux_file(file); 1735 struct inode *inode = file_inode(file); 1736 struct common_audit_data ad; 1737 u32 sid = cred_sid(cred); 1738 int rc; 1739 1740 ad.type = LSM_AUDIT_DATA_FILE; 1741 ad.u.file = file; 1742 1743 if (sid != fsec->sid) { 1744 rc = avc_has_perm(sid, fsec->sid, 1745 SECCLASS_FD, 1746 FD__USE, 1747 &ad); 1748 if (rc) 1749 goto out; 1750 } 1751 1752 #ifdef CONFIG_BPF_SYSCALL 1753 rc = bpf_fd_pass(file, cred_sid(cred)); 1754 if (rc) 1755 return rc; 1756 #endif 1757 1758 /* av is zero if only checking access to the descriptor. */ 1759 rc = 0; 1760 if (av) 1761 rc = inode_has_perm(cred, inode, av, &ad); 1762 1763 out: 1764 return rc; 1765 } 1766 1767 /* 1768 * Determine the label for an inode that might be unioned. 1769 */ 1770 static int 1771 selinux_determine_inode_label(const struct task_security_struct *tsec, 1772 struct inode *dir, 1773 const struct qstr *name, u16 tclass, 1774 u32 *_new_isid) 1775 { 1776 const struct superblock_security_struct *sbsec = 1777 selinux_superblock(dir->i_sb); 1778 1779 if ((sbsec->flags & SE_SBINITIALIZED) && 1780 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1781 *_new_isid = sbsec->mntpoint_sid; 1782 } else if ((sbsec->flags & SBLABEL_MNT) && 1783 tsec->create_sid) { 1784 *_new_isid = tsec->create_sid; 1785 } else { 1786 const struct inode_security_struct *dsec = inode_security(dir); 1787 return security_transition_sid(tsec->sid, 1788 dsec->sid, tclass, 1789 name, _new_isid); 1790 } 1791 1792 return 0; 1793 } 1794 1795 /* Check whether a task can create a file. */ 1796 static int may_create(struct inode *dir, 1797 struct dentry *dentry, 1798 u16 tclass) 1799 { 1800 const struct task_security_struct *tsec = selinux_cred(current_cred()); 1801 struct inode_security_struct *dsec; 1802 struct superblock_security_struct *sbsec; 1803 u32 sid, newsid; 1804 struct common_audit_data ad; 1805 int rc; 1806 1807 dsec = inode_security(dir); 1808 sbsec = selinux_superblock(dir->i_sb); 1809 1810 sid = tsec->sid; 1811 1812 ad.type = LSM_AUDIT_DATA_DENTRY; 1813 ad.u.dentry = dentry; 1814 1815 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1816 DIR__ADD_NAME | DIR__SEARCH, 1817 &ad); 1818 if (rc) 1819 return rc; 1820 1821 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, 1822 &newsid); 1823 if (rc) 1824 return rc; 1825 1826 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1827 if (rc) 1828 return rc; 1829 1830 return avc_has_perm(newsid, sbsec->sid, 1831 SECCLASS_FILESYSTEM, 1832 FILESYSTEM__ASSOCIATE, &ad); 1833 } 1834 1835 #define MAY_LINK 0 1836 #define MAY_UNLINK 1 1837 #define MAY_RMDIR 2 1838 1839 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1840 static int may_link(struct inode *dir, 1841 struct dentry *dentry, 1842 int kind) 1843 1844 { 1845 struct inode_security_struct *dsec, *isec; 1846 struct common_audit_data ad; 1847 u32 sid = current_sid(); 1848 u32 av; 1849 int rc; 1850 1851 dsec = inode_security(dir); 1852 isec = backing_inode_security(dentry); 1853 1854 ad.type = LSM_AUDIT_DATA_DENTRY; 1855 ad.u.dentry = dentry; 1856 1857 av = DIR__SEARCH; 1858 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1859 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1860 if (rc) 1861 return rc; 1862 1863 switch (kind) { 1864 case MAY_LINK: 1865 av = FILE__LINK; 1866 break; 1867 case MAY_UNLINK: 1868 av = FILE__UNLINK; 1869 break; 1870 case MAY_RMDIR: 1871 av = DIR__RMDIR; 1872 break; 1873 default: 1874 pr_warn("SELinux: %s: unrecognized kind %d\n", 1875 __func__, kind); 1876 return 0; 1877 } 1878 1879 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1880 return rc; 1881 } 1882 1883 static inline int may_rename(struct inode *old_dir, 1884 struct dentry *old_dentry, 1885 struct inode *new_dir, 1886 struct dentry *new_dentry) 1887 { 1888 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1889 struct common_audit_data ad; 1890 u32 sid = current_sid(); 1891 u32 av; 1892 int old_is_dir, new_is_dir; 1893 int rc; 1894 1895 old_dsec = inode_security(old_dir); 1896 old_isec = backing_inode_security(old_dentry); 1897 old_is_dir = d_is_dir(old_dentry); 1898 new_dsec = inode_security(new_dir); 1899 1900 ad.type = LSM_AUDIT_DATA_DENTRY; 1901 1902 ad.u.dentry = old_dentry; 1903 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1904 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1905 if (rc) 1906 return rc; 1907 rc = avc_has_perm(sid, old_isec->sid, 1908 old_isec->sclass, FILE__RENAME, &ad); 1909 if (rc) 1910 return rc; 1911 if (old_is_dir && new_dir != old_dir) { 1912 rc = avc_has_perm(sid, old_isec->sid, 1913 old_isec->sclass, DIR__REPARENT, &ad); 1914 if (rc) 1915 return rc; 1916 } 1917 1918 ad.u.dentry = new_dentry; 1919 av = DIR__ADD_NAME | DIR__SEARCH; 1920 if (d_is_positive(new_dentry)) 1921 av |= DIR__REMOVE_NAME; 1922 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1923 if (rc) 1924 return rc; 1925 if (d_is_positive(new_dentry)) { 1926 new_isec = backing_inode_security(new_dentry); 1927 new_is_dir = d_is_dir(new_dentry); 1928 rc = avc_has_perm(sid, new_isec->sid, 1929 new_isec->sclass, 1930 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1931 if (rc) 1932 return rc; 1933 } 1934 1935 return 0; 1936 } 1937 1938 /* Check whether a task can perform a filesystem operation. */ 1939 static int superblock_has_perm(const struct cred *cred, 1940 const struct super_block *sb, 1941 u32 perms, 1942 struct common_audit_data *ad) 1943 { 1944 struct superblock_security_struct *sbsec; 1945 u32 sid = cred_sid(cred); 1946 1947 sbsec = selinux_superblock(sb); 1948 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1949 } 1950 1951 /* Convert a Linux mode and permission mask to an access vector. */ 1952 static inline u32 file_mask_to_av(int mode, int mask) 1953 { 1954 u32 av = 0; 1955 1956 if (!S_ISDIR(mode)) { 1957 if (mask & MAY_EXEC) 1958 av |= FILE__EXECUTE; 1959 if (mask & MAY_READ) 1960 av |= FILE__READ; 1961 1962 if (mask & MAY_APPEND) 1963 av |= FILE__APPEND; 1964 else if (mask & MAY_WRITE) 1965 av |= FILE__WRITE; 1966 1967 } else { 1968 if (mask & MAY_EXEC) 1969 av |= DIR__SEARCH; 1970 if (mask & MAY_WRITE) 1971 av |= DIR__WRITE; 1972 if (mask & MAY_READ) 1973 av |= DIR__READ; 1974 } 1975 1976 return av; 1977 } 1978 1979 /* Convert a Linux file to an access vector. */ 1980 static inline u32 file_to_av(const struct file *file) 1981 { 1982 u32 av = 0; 1983 1984 if (file->f_mode & FMODE_READ) 1985 av |= FILE__READ; 1986 if (file->f_mode & FMODE_WRITE) { 1987 if (file->f_flags & O_APPEND) 1988 av |= FILE__APPEND; 1989 else 1990 av |= FILE__WRITE; 1991 } 1992 if (!av) { 1993 /* 1994 * Special file opened with flags 3 for ioctl-only use. 1995 */ 1996 av = FILE__IOCTL; 1997 } 1998 1999 return av; 2000 } 2001 2002 /* 2003 * Convert a file to an access vector and include the correct 2004 * open permission. 2005 */ 2006 static inline u32 open_file_to_av(struct file *file) 2007 { 2008 u32 av = file_to_av(file); 2009 struct inode *inode = file_inode(file); 2010 2011 if (selinux_policycap_openperm() && 2012 inode->i_sb->s_magic != SOCKFS_MAGIC) 2013 av |= FILE__OPEN; 2014 2015 return av; 2016 } 2017 2018 /* Hook functions begin here. */ 2019 2020 static int selinux_binder_set_context_mgr(const struct cred *mgr) 2021 { 2022 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, 2023 BINDER__SET_CONTEXT_MGR, NULL); 2024 } 2025 2026 static int selinux_binder_transaction(const struct cred *from, 2027 const struct cred *to) 2028 { 2029 u32 mysid = current_sid(); 2030 u32 fromsid = cred_sid(from); 2031 u32 tosid = cred_sid(to); 2032 int rc; 2033 2034 if (mysid != fromsid) { 2035 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2036 BINDER__IMPERSONATE, NULL); 2037 if (rc) 2038 return rc; 2039 } 2040 2041 return avc_has_perm(fromsid, tosid, 2042 SECCLASS_BINDER, BINDER__CALL, NULL); 2043 } 2044 2045 static int selinux_binder_transfer_binder(const struct cred *from, 2046 const struct cred *to) 2047 { 2048 return avc_has_perm(cred_sid(from), cred_sid(to), 2049 SECCLASS_BINDER, BINDER__TRANSFER, 2050 NULL); 2051 } 2052 2053 static int selinux_binder_transfer_file(const struct cred *from, 2054 const struct cred *to, 2055 const struct file *file) 2056 { 2057 u32 sid = cred_sid(to); 2058 struct file_security_struct *fsec = selinux_file(file); 2059 struct dentry *dentry = file->f_path.dentry; 2060 struct inode_security_struct *isec; 2061 struct common_audit_data ad; 2062 int rc; 2063 2064 ad.type = LSM_AUDIT_DATA_PATH; 2065 ad.u.path = file->f_path; 2066 2067 if (sid != fsec->sid) { 2068 rc = avc_has_perm(sid, fsec->sid, 2069 SECCLASS_FD, 2070 FD__USE, 2071 &ad); 2072 if (rc) 2073 return rc; 2074 } 2075 2076 #ifdef CONFIG_BPF_SYSCALL 2077 rc = bpf_fd_pass(file, sid); 2078 if (rc) 2079 return rc; 2080 #endif 2081 2082 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2083 return 0; 2084 2085 isec = backing_inode_security(dentry); 2086 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2087 &ad); 2088 } 2089 2090 static int selinux_ptrace_access_check(struct task_struct *child, 2091 unsigned int mode) 2092 { 2093 u32 sid = current_sid(); 2094 u32 csid = task_sid_obj(child); 2095 2096 if (mode & PTRACE_MODE_READ) 2097 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, 2098 NULL); 2099 2100 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, 2101 NULL); 2102 } 2103 2104 static int selinux_ptrace_traceme(struct task_struct *parent) 2105 { 2106 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), 2107 SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2108 } 2109 2110 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, 2111 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2112 { 2113 return avc_has_perm(current_sid(), task_sid_obj(target), 2114 SECCLASS_PROCESS, PROCESS__GETCAP, NULL); 2115 } 2116 2117 static int selinux_capset(struct cred *new, const struct cred *old, 2118 const kernel_cap_t *effective, 2119 const kernel_cap_t *inheritable, 2120 const kernel_cap_t *permitted) 2121 { 2122 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2123 PROCESS__SETCAP, NULL); 2124 } 2125 2126 /* 2127 * (This comment used to live with the selinux_task_setuid hook, 2128 * which was removed). 2129 * 2130 * Since setuid only affects the current process, and since the SELinux 2131 * controls are not based on the Linux identity attributes, SELinux does not 2132 * need to control this operation. However, SELinux does control the use of 2133 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2134 */ 2135 2136 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2137 int cap, unsigned int opts) 2138 { 2139 return cred_has_capability(cred, cap, opts, ns == &init_user_ns); 2140 } 2141 2142 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb) 2143 { 2144 const struct cred *cred = current_cred(); 2145 int rc = 0; 2146 2147 if (!sb) 2148 return 0; 2149 2150 switch (cmds) { 2151 case Q_SYNC: 2152 case Q_QUOTAON: 2153 case Q_QUOTAOFF: 2154 case Q_SETINFO: 2155 case Q_SETQUOTA: 2156 case Q_XQUOTAOFF: 2157 case Q_XQUOTAON: 2158 case Q_XSETQLIM: 2159 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2160 break; 2161 case Q_GETFMT: 2162 case Q_GETINFO: 2163 case Q_GETQUOTA: 2164 case Q_XGETQUOTA: 2165 case Q_XGETQSTAT: 2166 case Q_XGETQSTATV: 2167 case Q_XGETNEXTQUOTA: 2168 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2169 break; 2170 default: 2171 rc = 0; /* let the kernel handle invalid cmds */ 2172 break; 2173 } 2174 return rc; 2175 } 2176 2177 static int selinux_quota_on(struct dentry *dentry) 2178 { 2179 const struct cred *cred = current_cred(); 2180 2181 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2182 } 2183 2184 static int selinux_syslog(int type) 2185 { 2186 switch (type) { 2187 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2188 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2189 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2190 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2191 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2192 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2193 /* Set level of messages printed to console */ 2194 case SYSLOG_ACTION_CONSOLE_LEVEL: 2195 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2196 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2197 NULL); 2198 } 2199 /* All other syslog types */ 2200 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 2201 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2202 } 2203 2204 /* 2205 * Check that a process has enough memory to allocate a new virtual 2206 * mapping. 0 means there is enough memory for the allocation to 2207 * succeed and -ENOMEM implies there is not. 2208 * 2209 * Do not audit the selinux permission check, as this is applied to all 2210 * processes that allocate mappings. 2211 */ 2212 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2213 { 2214 int rc, cap_sys_admin = 0; 2215 2216 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2217 CAP_OPT_NOAUDIT, true); 2218 if (rc == 0) 2219 cap_sys_admin = 1; 2220 2221 return cap_sys_admin; 2222 } 2223 2224 /* binprm security operations */ 2225 2226 static u32 ptrace_parent_sid(void) 2227 { 2228 u32 sid = 0; 2229 struct task_struct *tracer; 2230 2231 rcu_read_lock(); 2232 tracer = ptrace_parent(current); 2233 if (tracer) 2234 sid = task_sid_obj(tracer); 2235 rcu_read_unlock(); 2236 2237 return sid; 2238 } 2239 2240 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2241 const struct task_security_struct *old_tsec, 2242 const struct task_security_struct *new_tsec) 2243 { 2244 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2245 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2246 int rc; 2247 u32 av; 2248 2249 if (!nnp && !nosuid) 2250 return 0; /* neither NNP nor nosuid */ 2251 2252 if (new_tsec->sid == old_tsec->sid) 2253 return 0; /* No change in credentials */ 2254 2255 /* 2256 * If the policy enables the nnp_nosuid_transition policy capability, 2257 * then we permit transitions under NNP or nosuid if the 2258 * policy allows the corresponding permission between 2259 * the old and new contexts. 2260 */ 2261 if (selinux_policycap_nnp_nosuid_transition()) { 2262 av = 0; 2263 if (nnp) 2264 av |= PROCESS2__NNP_TRANSITION; 2265 if (nosuid) 2266 av |= PROCESS2__NOSUID_TRANSITION; 2267 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2268 SECCLASS_PROCESS2, av, NULL); 2269 if (!rc) 2270 return 0; 2271 } 2272 2273 /* 2274 * We also permit NNP or nosuid transitions to bounded SIDs, 2275 * i.e. SIDs that are guaranteed to only be allowed a subset 2276 * of the permissions of the current SID. 2277 */ 2278 rc = security_bounded_transition(old_tsec->sid, 2279 new_tsec->sid); 2280 if (!rc) 2281 return 0; 2282 2283 /* 2284 * On failure, preserve the errno values for NNP vs nosuid. 2285 * NNP: Operation not permitted for caller. 2286 * nosuid: Permission denied to file. 2287 */ 2288 if (nnp) 2289 return -EPERM; 2290 return -EACCES; 2291 } 2292 2293 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) 2294 { 2295 const struct task_security_struct *old_tsec; 2296 struct task_security_struct *new_tsec; 2297 struct inode_security_struct *isec; 2298 struct common_audit_data ad; 2299 struct inode *inode = file_inode(bprm->file); 2300 int rc; 2301 2302 /* SELinux context only depends on initial program or script and not 2303 * the script interpreter */ 2304 2305 old_tsec = selinux_cred(current_cred()); 2306 new_tsec = selinux_cred(bprm->cred); 2307 isec = inode_security(inode); 2308 2309 /* Default to the current task SID. */ 2310 new_tsec->sid = old_tsec->sid; 2311 new_tsec->osid = old_tsec->sid; 2312 2313 /* Reset fs, key, and sock SIDs on execve. */ 2314 new_tsec->create_sid = 0; 2315 new_tsec->keycreate_sid = 0; 2316 new_tsec->sockcreate_sid = 0; 2317 2318 /* 2319 * Before policy is loaded, label any task outside kernel space 2320 * as SECINITSID_INIT, so that any userspace tasks surviving from 2321 * early boot end up with a label different from SECINITSID_KERNEL 2322 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL). 2323 */ 2324 if (!selinux_initialized()) { 2325 new_tsec->sid = SECINITSID_INIT; 2326 /* also clear the exec_sid just in case */ 2327 new_tsec->exec_sid = 0; 2328 return 0; 2329 } 2330 2331 if (old_tsec->exec_sid) { 2332 new_tsec->sid = old_tsec->exec_sid; 2333 /* Reset exec SID on execve. */ 2334 new_tsec->exec_sid = 0; 2335 2336 /* Fail on NNP or nosuid if not an allowed transition. */ 2337 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2338 if (rc) 2339 return rc; 2340 } else { 2341 /* Check for a default transition on this program. */ 2342 rc = security_transition_sid(old_tsec->sid, 2343 isec->sid, SECCLASS_PROCESS, NULL, 2344 &new_tsec->sid); 2345 if (rc) 2346 return rc; 2347 2348 /* 2349 * Fallback to old SID on NNP or nosuid if not an allowed 2350 * transition. 2351 */ 2352 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2353 if (rc) 2354 new_tsec->sid = old_tsec->sid; 2355 } 2356 2357 ad.type = LSM_AUDIT_DATA_FILE; 2358 ad.u.file = bprm->file; 2359 2360 if (new_tsec->sid == old_tsec->sid) { 2361 rc = avc_has_perm(old_tsec->sid, isec->sid, 2362 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2363 if (rc) 2364 return rc; 2365 } else { 2366 /* Check permissions for the transition. */ 2367 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2368 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2369 if (rc) 2370 return rc; 2371 2372 rc = avc_has_perm(new_tsec->sid, isec->sid, 2373 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2374 if (rc) 2375 return rc; 2376 2377 /* Check for shared state */ 2378 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2379 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2380 SECCLASS_PROCESS, PROCESS__SHARE, 2381 NULL); 2382 if (rc) 2383 return -EPERM; 2384 } 2385 2386 /* Make sure that anyone attempting to ptrace over a task that 2387 * changes its SID has the appropriate permit */ 2388 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2389 u32 ptsid = ptrace_parent_sid(); 2390 if (ptsid != 0) { 2391 rc = avc_has_perm(ptsid, new_tsec->sid, 2392 SECCLASS_PROCESS, 2393 PROCESS__PTRACE, NULL); 2394 if (rc) 2395 return -EPERM; 2396 } 2397 } 2398 2399 /* Clear any possibly unsafe personality bits on exec: */ 2400 bprm->per_clear |= PER_CLEAR_ON_SETID; 2401 2402 /* Enable secure mode for SIDs transitions unless 2403 the noatsecure permission is granted between 2404 the two SIDs, i.e. ahp returns 0. */ 2405 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2406 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2407 NULL); 2408 bprm->secureexec |= !!rc; 2409 } 2410 2411 return 0; 2412 } 2413 2414 static int match_file(const void *p, struct file *file, unsigned fd) 2415 { 2416 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2417 } 2418 2419 /* Derived from fs/exec.c:flush_old_files. */ 2420 static inline void flush_unauthorized_files(const struct cred *cred, 2421 struct files_struct *files) 2422 { 2423 struct file *file, *devnull = NULL; 2424 struct tty_struct *tty; 2425 int drop_tty = 0; 2426 unsigned n; 2427 2428 tty = get_current_tty(); 2429 if (tty) { 2430 spin_lock(&tty->files_lock); 2431 if (!list_empty(&tty->tty_files)) { 2432 struct tty_file_private *file_priv; 2433 2434 /* Revalidate access to controlling tty. 2435 Use file_path_has_perm on the tty path directly 2436 rather than using file_has_perm, as this particular 2437 open file may belong to another process and we are 2438 only interested in the inode-based check here. */ 2439 file_priv = list_first_entry(&tty->tty_files, 2440 struct tty_file_private, list); 2441 file = file_priv->file; 2442 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2443 drop_tty = 1; 2444 } 2445 spin_unlock(&tty->files_lock); 2446 tty_kref_put(tty); 2447 } 2448 /* Reset controlling tty. */ 2449 if (drop_tty) 2450 no_tty(); 2451 2452 /* Revalidate access to inherited open files. */ 2453 n = iterate_fd(files, 0, match_file, cred); 2454 if (!n) /* none found? */ 2455 return; 2456 2457 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2458 if (IS_ERR(devnull)) 2459 devnull = NULL; 2460 /* replace all the matching ones with this */ 2461 do { 2462 replace_fd(n - 1, devnull, 0); 2463 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2464 if (devnull) 2465 fput(devnull); 2466 } 2467 2468 /* 2469 * Prepare a process for imminent new credential changes due to exec 2470 */ 2471 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) 2472 { 2473 struct task_security_struct *new_tsec; 2474 struct rlimit *rlim, *initrlim; 2475 int rc, i; 2476 2477 new_tsec = selinux_cred(bprm->cred); 2478 if (new_tsec->sid == new_tsec->osid) 2479 return; 2480 2481 /* Close files for which the new task SID is not authorized. */ 2482 flush_unauthorized_files(bprm->cred, current->files); 2483 2484 /* Always clear parent death signal on SID transitions. */ 2485 current->pdeath_signal = 0; 2486 2487 /* Check whether the new SID can inherit resource limits from the old 2488 * SID. If not, reset all soft limits to the lower of the current 2489 * task's hard limit and the init task's soft limit. 2490 * 2491 * Note that the setting of hard limits (even to lower them) can be 2492 * controlled by the setrlimit check. The inclusion of the init task's 2493 * soft limit into the computation is to avoid resetting soft limits 2494 * higher than the default soft limit for cases where the default is 2495 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2496 */ 2497 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2498 PROCESS__RLIMITINH, NULL); 2499 if (rc) { 2500 /* protect against do_prlimit() */ 2501 task_lock(current); 2502 for (i = 0; i < RLIM_NLIMITS; i++) { 2503 rlim = current->signal->rlim + i; 2504 initrlim = init_task.signal->rlim + i; 2505 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2506 } 2507 task_unlock(current); 2508 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2509 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2510 } 2511 } 2512 2513 /* 2514 * Clean up the process immediately after the installation of new credentials 2515 * due to exec 2516 */ 2517 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) 2518 { 2519 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2520 u32 osid, sid; 2521 int rc; 2522 2523 osid = tsec->osid; 2524 sid = tsec->sid; 2525 2526 if (sid == osid) 2527 return; 2528 2529 /* Check whether the new SID can inherit signal state from the old SID. 2530 * If not, clear itimers to avoid subsequent signal generation and 2531 * flush and unblock signals. 2532 * 2533 * This must occur _after_ the task SID has been updated so that any 2534 * kill done after the flush will be checked against the new SID. 2535 */ 2536 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2537 if (rc) { 2538 clear_itimer(); 2539 2540 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); 2541 if (!fatal_signal_pending(current)) { 2542 flush_sigqueue(¤t->pending); 2543 flush_sigqueue(¤t->signal->shared_pending); 2544 flush_signal_handlers(current, 1); 2545 sigemptyset(¤t->blocked); 2546 recalc_sigpending(); 2547 } 2548 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); 2549 } 2550 2551 /* Wake up the parent if it is waiting so that it can recheck 2552 * wait permission to the new task SID. */ 2553 read_lock(&tasklist_lock); 2554 __wake_up_parent(current, unrcu_pointer(current->real_parent)); 2555 read_unlock(&tasklist_lock); 2556 } 2557 2558 /* superblock security operations */ 2559 2560 static int selinux_sb_alloc_security(struct super_block *sb) 2561 { 2562 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2563 2564 mutex_init(&sbsec->lock); 2565 INIT_LIST_HEAD(&sbsec->isec_head); 2566 spin_lock_init(&sbsec->isec_lock); 2567 sbsec->sid = SECINITSID_UNLABELED; 2568 sbsec->def_sid = SECINITSID_FILE; 2569 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 2570 2571 return 0; 2572 } 2573 2574 static inline int opt_len(const char *s) 2575 { 2576 bool open_quote = false; 2577 int len; 2578 char c; 2579 2580 for (len = 0; (c = s[len]) != '\0'; len++) { 2581 if (c == '"') 2582 open_quote = !open_quote; 2583 if (c == ',' && !open_quote) 2584 break; 2585 } 2586 return len; 2587 } 2588 2589 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) 2590 { 2591 char *from = options; 2592 char *to = options; 2593 bool first = true; 2594 int rc; 2595 2596 while (1) { 2597 int len = opt_len(from); 2598 int token; 2599 char *arg = NULL; 2600 2601 token = match_opt_prefix(from, len, &arg); 2602 2603 if (token != Opt_error) { 2604 char *p, *q; 2605 2606 /* strip quotes */ 2607 if (arg) { 2608 for (p = q = arg; p < from + len; p++) { 2609 char c = *p; 2610 if (c != '"') 2611 *q++ = c; 2612 } 2613 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); 2614 if (!arg) { 2615 rc = -ENOMEM; 2616 goto free_opt; 2617 } 2618 } 2619 rc = selinux_add_opt(token, arg, mnt_opts); 2620 kfree(arg); 2621 arg = NULL; 2622 if (unlikely(rc)) { 2623 goto free_opt; 2624 } 2625 } else { 2626 if (!first) { // copy with preceding comma 2627 from--; 2628 len++; 2629 } 2630 if (to != from) 2631 memmove(to, from, len); 2632 to += len; 2633 first = false; 2634 } 2635 if (!from[len]) 2636 break; 2637 from += len + 1; 2638 } 2639 *to = '\0'; 2640 return 0; 2641 2642 free_opt: 2643 if (*mnt_opts) { 2644 selinux_free_mnt_opts(*mnt_opts); 2645 *mnt_opts = NULL; 2646 } 2647 return rc; 2648 } 2649 2650 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) 2651 { 2652 struct selinux_mnt_opts *opts = mnt_opts; 2653 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2654 2655 /* 2656 * Superblock not initialized (i.e. no options) - reject if any 2657 * options specified, otherwise accept. 2658 */ 2659 if (!(sbsec->flags & SE_SBINITIALIZED)) 2660 return opts ? 1 : 0; 2661 2662 /* 2663 * Superblock initialized and no options specified - reject if 2664 * superblock has any options set, otherwise accept. 2665 */ 2666 if (!opts) 2667 return (sbsec->flags & SE_MNTMASK) ? 1 : 0; 2668 2669 if (opts->fscontext_sid) { 2670 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2671 opts->fscontext_sid)) 2672 return 1; 2673 } 2674 if (opts->context_sid) { 2675 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2676 opts->context_sid)) 2677 return 1; 2678 } 2679 if (opts->rootcontext_sid) { 2680 struct inode_security_struct *root_isec; 2681 2682 root_isec = backing_inode_security(sb->s_root); 2683 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2684 opts->rootcontext_sid)) 2685 return 1; 2686 } 2687 if (opts->defcontext_sid) { 2688 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2689 opts->defcontext_sid)) 2690 return 1; 2691 } 2692 return 0; 2693 } 2694 2695 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) 2696 { 2697 struct selinux_mnt_opts *opts = mnt_opts; 2698 struct superblock_security_struct *sbsec = selinux_superblock(sb); 2699 2700 if (!(sbsec->flags & SE_SBINITIALIZED)) 2701 return 0; 2702 2703 if (!opts) 2704 return 0; 2705 2706 if (opts->fscontext_sid) { 2707 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 2708 opts->fscontext_sid)) 2709 goto out_bad_option; 2710 } 2711 if (opts->context_sid) { 2712 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 2713 opts->context_sid)) 2714 goto out_bad_option; 2715 } 2716 if (opts->rootcontext_sid) { 2717 struct inode_security_struct *root_isec; 2718 root_isec = backing_inode_security(sb->s_root); 2719 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 2720 opts->rootcontext_sid)) 2721 goto out_bad_option; 2722 } 2723 if (opts->defcontext_sid) { 2724 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 2725 opts->defcontext_sid)) 2726 goto out_bad_option; 2727 } 2728 return 0; 2729 2730 out_bad_option: 2731 pr_warn("SELinux: unable to change security options " 2732 "during remount (dev %s, type=%s)\n", sb->s_id, 2733 sb->s_type->name); 2734 return -EINVAL; 2735 } 2736 2737 static int selinux_sb_kern_mount(const struct super_block *sb) 2738 { 2739 const struct cred *cred = current_cred(); 2740 struct common_audit_data ad; 2741 2742 ad.type = LSM_AUDIT_DATA_DENTRY; 2743 ad.u.dentry = sb->s_root; 2744 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2745 } 2746 2747 static int selinux_sb_statfs(struct dentry *dentry) 2748 { 2749 const struct cred *cred = current_cred(); 2750 struct common_audit_data ad; 2751 2752 ad.type = LSM_AUDIT_DATA_DENTRY; 2753 ad.u.dentry = dentry->d_sb->s_root; 2754 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2755 } 2756 2757 static int selinux_mount(const char *dev_name, 2758 const struct path *path, 2759 const char *type, 2760 unsigned long flags, 2761 void *data) 2762 { 2763 const struct cred *cred = current_cred(); 2764 2765 if (flags & MS_REMOUNT) 2766 return superblock_has_perm(cred, path->dentry->d_sb, 2767 FILESYSTEM__REMOUNT, NULL); 2768 else 2769 return path_has_perm(cred, path, FILE__MOUNTON); 2770 } 2771 2772 static int selinux_move_mount(const struct path *from_path, 2773 const struct path *to_path) 2774 { 2775 const struct cred *cred = current_cred(); 2776 2777 return path_has_perm(cred, to_path, FILE__MOUNTON); 2778 } 2779 2780 static int selinux_umount(struct vfsmount *mnt, int flags) 2781 { 2782 const struct cred *cred = current_cred(); 2783 2784 return superblock_has_perm(cred, mnt->mnt_sb, 2785 FILESYSTEM__UNMOUNT, NULL); 2786 } 2787 2788 static int selinux_fs_context_submount(struct fs_context *fc, 2789 struct super_block *reference) 2790 { 2791 const struct superblock_security_struct *sbsec = selinux_superblock(reference); 2792 struct selinux_mnt_opts *opts; 2793 2794 /* 2795 * Ensure that fc->security remains NULL when no options are set 2796 * as expected by selinux_set_mnt_opts(). 2797 */ 2798 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) 2799 return 0; 2800 2801 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 2802 if (!opts) 2803 return -ENOMEM; 2804 2805 if (sbsec->flags & FSCONTEXT_MNT) 2806 opts->fscontext_sid = sbsec->sid; 2807 if (sbsec->flags & CONTEXT_MNT) 2808 opts->context_sid = sbsec->mntpoint_sid; 2809 if (sbsec->flags & DEFCONTEXT_MNT) 2810 opts->defcontext_sid = sbsec->def_sid; 2811 fc->security = opts; 2812 return 0; 2813 } 2814 2815 static int selinux_fs_context_dup(struct fs_context *fc, 2816 struct fs_context *src_fc) 2817 { 2818 const struct selinux_mnt_opts *src = src_fc->security; 2819 2820 if (!src) 2821 return 0; 2822 2823 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); 2824 return fc->security ? 0 : -ENOMEM; 2825 } 2826 2827 static const struct fs_parameter_spec selinux_fs_parameters[] = { 2828 fsparam_string(CONTEXT_STR, Opt_context), 2829 fsparam_string(DEFCONTEXT_STR, Opt_defcontext), 2830 fsparam_string(FSCONTEXT_STR, Opt_fscontext), 2831 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), 2832 fsparam_flag (SECLABEL_STR, Opt_seclabel), 2833 {} 2834 }; 2835 2836 static int selinux_fs_context_parse_param(struct fs_context *fc, 2837 struct fs_parameter *param) 2838 { 2839 struct fs_parse_result result; 2840 int opt; 2841 2842 opt = fs_parse(fc, selinux_fs_parameters, param, &result); 2843 if (opt < 0) 2844 return opt; 2845 2846 return selinux_add_opt(opt, param->string, &fc->security); 2847 } 2848 2849 /* inode security operations */ 2850 2851 static int selinux_inode_alloc_security(struct inode *inode) 2852 { 2853 struct inode_security_struct *isec = selinux_inode(inode); 2854 u32 sid = current_sid(); 2855 2856 spin_lock_init(&isec->lock); 2857 INIT_LIST_HEAD(&isec->list); 2858 isec->inode = inode; 2859 isec->sid = SECINITSID_UNLABELED; 2860 isec->sclass = SECCLASS_FILE; 2861 isec->task_sid = sid; 2862 isec->initialized = LABEL_INVALID; 2863 2864 return 0; 2865 } 2866 2867 static void selinux_inode_free_security(struct inode *inode) 2868 { 2869 inode_free_security(inode); 2870 } 2871 2872 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2873 const struct qstr *name, 2874 const char **xattr_name, void **ctx, 2875 u32 *ctxlen) 2876 { 2877 u32 newsid; 2878 int rc; 2879 2880 rc = selinux_determine_inode_label(selinux_cred(current_cred()), 2881 d_inode(dentry->d_parent), name, 2882 inode_mode_to_security_class(mode), 2883 &newsid); 2884 if (rc) 2885 return rc; 2886 2887 if (xattr_name) 2888 *xattr_name = XATTR_NAME_SELINUX; 2889 2890 return security_sid_to_context(newsid, (char **)ctx, 2891 ctxlen); 2892 } 2893 2894 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2895 struct qstr *name, 2896 const struct cred *old, 2897 struct cred *new) 2898 { 2899 u32 newsid; 2900 int rc; 2901 struct task_security_struct *tsec; 2902 2903 rc = selinux_determine_inode_label(selinux_cred(old), 2904 d_inode(dentry->d_parent), name, 2905 inode_mode_to_security_class(mode), 2906 &newsid); 2907 if (rc) 2908 return rc; 2909 2910 tsec = selinux_cred(new); 2911 tsec->create_sid = newsid; 2912 return 0; 2913 } 2914 2915 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2916 const struct qstr *qstr, 2917 struct xattr *xattrs, int *xattr_count) 2918 { 2919 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2920 struct superblock_security_struct *sbsec; 2921 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); 2922 u32 newsid, clen; 2923 u16 newsclass; 2924 int rc; 2925 char *context; 2926 2927 sbsec = selinux_superblock(dir->i_sb); 2928 2929 newsid = tsec->create_sid; 2930 newsclass = inode_mode_to_security_class(inode->i_mode); 2931 rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid); 2932 if (rc) 2933 return rc; 2934 2935 /* Possibly defer initialization to selinux_complete_init. */ 2936 if (sbsec->flags & SE_SBINITIALIZED) { 2937 struct inode_security_struct *isec = selinux_inode(inode); 2938 isec->sclass = newsclass; 2939 isec->sid = newsid; 2940 isec->initialized = LABEL_INITIALIZED; 2941 } 2942 2943 if (!selinux_initialized() || 2944 !(sbsec->flags & SBLABEL_MNT)) 2945 return -EOPNOTSUPP; 2946 2947 if (xattr) { 2948 rc = security_sid_to_context_force(newsid, 2949 &context, &clen); 2950 if (rc) 2951 return rc; 2952 xattr->value = context; 2953 xattr->value_len = clen; 2954 xattr->name = XATTR_SELINUX_SUFFIX; 2955 } 2956 2957 return 0; 2958 } 2959 2960 static int selinux_inode_init_security_anon(struct inode *inode, 2961 const struct qstr *name, 2962 const struct inode *context_inode) 2963 { 2964 const struct task_security_struct *tsec = selinux_cred(current_cred()); 2965 struct common_audit_data ad; 2966 struct inode_security_struct *isec; 2967 int rc; 2968 2969 if (unlikely(!selinux_initialized())) 2970 return 0; 2971 2972 isec = selinux_inode(inode); 2973 2974 /* 2975 * We only get here once per ephemeral inode. The inode has 2976 * been initialized via inode_alloc_security but is otherwise 2977 * untouched. 2978 */ 2979 2980 if (context_inode) { 2981 struct inode_security_struct *context_isec = 2982 selinux_inode(context_inode); 2983 if (context_isec->initialized != LABEL_INITIALIZED) { 2984 pr_err("SELinux: context_inode is not initialized\n"); 2985 return -EACCES; 2986 } 2987 2988 isec->sclass = context_isec->sclass; 2989 isec->sid = context_isec->sid; 2990 } else { 2991 isec->sclass = SECCLASS_ANON_INODE; 2992 rc = security_transition_sid( 2993 tsec->sid, tsec->sid, 2994 isec->sclass, name, &isec->sid); 2995 if (rc) 2996 return rc; 2997 } 2998 2999 isec->initialized = LABEL_INITIALIZED; 3000 /* 3001 * Now that we've initialized security, check whether we're 3002 * allowed to actually create this type of anonymous inode. 3003 */ 3004 3005 ad.type = LSM_AUDIT_DATA_ANONINODE; 3006 ad.u.anonclass = name ? (const char *)name->name : "?"; 3007 3008 return avc_has_perm(tsec->sid, 3009 isec->sid, 3010 isec->sclass, 3011 FILE__CREATE, 3012 &ad); 3013 } 3014 3015 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3016 { 3017 return may_create(dir, dentry, SECCLASS_FILE); 3018 } 3019 3020 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3021 { 3022 return may_link(dir, old_dentry, MAY_LINK); 3023 } 3024 3025 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3026 { 3027 return may_link(dir, dentry, MAY_UNLINK); 3028 } 3029 3030 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3031 { 3032 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3033 } 3034 3035 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3036 { 3037 return may_create(dir, dentry, SECCLASS_DIR); 3038 } 3039 3040 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3041 { 3042 return may_link(dir, dentry, MAY_RMDIR); 3043 } 3044 3045 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3046 { 3047 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3048 } 3049 3050 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3051 struct inode *new_inode, struct dentry *new_dentry) 3052 { 3053 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3054 } 3055 3056 static int selinux_inode_readlink(struct dentry *dentry) 3057 { 3058 const struct cred *cred = current_cred(); 3059 3060 return dentry_has_perm(cred, dentry, FILE__READ); 3061 } 3062 3063 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3064 bool rcu) 3065 { 3066 const struct cred *cred = current_cred(); 3067 struct common_audit_data ad; 3068 struct inode_security_struct *isec; 3069 u32 sid; 3070 3071 ad.type = LSM_AUDIT_DATA_DENTRY; 3072 ad.u.dentry = dentry; 3073 sid = cred_sid(cred); 3074 isec = inode_security_rcu(inode, rcu); 3075 if (IS_ERR(isec)) 3076 return PTR_ERR(isec); 3077 3078 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); 3079 } 3080 3081 static noinline int audit_inode_permission(struct inode *inode, 3082 u32 perms, u32 audited, u32 denied, 3083 int result) 3084 { 3085 struct common_audit_data ad; 3086 struct inode_security_struct *isec = selinux_inode(inode); 3087 3088 ad.type = LSM_AUDIT_DATA_INODE; 3089 ad.u.inode = inode; 3090 3091 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3092 audited, denied, result, &ad); 3093 } 3094 3095 static int selinux_inode_permission(struct inode *inode, int mask) 3096 { 3097 const struct cred *cred = current_cred(); 3098 u32 perms; 3099 bool from_access; 3100 bool no_block = mask & MAY_NOT_BLOCK; 3101 struct inode_security_struct *isec; 3102 u32 sid; 3103 struct av_decision avd; 3104 int rc, rc2; 3105 u32 audited, denied; 3106 3107 from_access = mask & MAY_ACCESS; 3108 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3109 3110 /* No permission to check. Existence test. */ 3111 if (!mask) 3112 return 0; 3113 3114 if (unlikely(IS_PRIVATE(inode))) 3115 return 0; 3116 3117 perms = file_mask_to_av(inode->i_mode, mask); 3118 3119 sid = cred_sid(cred); 3120 isec = inode_security_rcu(inode, no_block); 3121 if (IS_ERR(isec)) 3122 return PTR_ERR(isec); 3123 3124 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, 3125 &avd); 3126 audited = avc_audit_required(perms, &avd, rc, 3127 from_access ? FILE__AUDIT_ACCESS : 0, 3128 &denied); 3129 if (likely(!audited)) 3130 return rc; 3131 3132 rc2 = audit_inode_permission(inode, perms, audited, denied, rc); 3133 if (rc2) 3134 return rc2; 3135 return rc; 3136 } 3137 3138 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 3139 struct iattr *iattr) 3140 { 3141 const struct cred *cred = current_cred(); 3142 struct inode *inode = d_backing_inode(dentry); 3143 unsigned int ia_valid = iattr->ia_valid; 3144 __u32 av = FILE__WRITE; 3145 3146 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3147 if (ia_valid & ATTR_FORCE) { 3148 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3149 ATTR_FORCE); 3150 if (!ia_valid) 3151 return 0; 3152 } 3153 3154 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3155 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3156 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3157 3158 if (selinux_policycap_openperm() && 3159 inode->i_sb->s_magic != SOCKFS_MAGIC && 3160 (ia_valid & ATTR_SIZE) && 3161 !(ia_valid & ATTR_FILE)) 3162 av |= FILE__OPEN; 3163 3164 return dentry_has_perm(cred, dentry, av); 3165 } 3166 3167 static int selinux_inode_getattr(const struct path *path) 3168 { 3169 return path_has_perm(current_cred(), path, FILE__GETATTR); 3170 } 3171 3172 static bool has_cap_mac_admin(bool audit) 3173 { 3174 const struct cred *cred = current_cred(); 3175 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; 3176 3177 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) 3178 return false; 3179 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) 3180 return false; 3181 return true; 3182 } 3183 3184 static int selinux_inode_setxattr(struct mnt_idmap *idmap, 3185 struct dentry *dentry, const char *name, 3186 const void *value, size_t size, int flags) 3187 { 3188 struct inode *inode = d_backing_inode(dentry); 3189 struct inode_security_struct *isec; 3190 struct superblock_security_struct *sbsec; 3191 struct common_audit_data ad; 3192 u32 newsid, sid = current_sid(); 3193 int rc = 0; 3194 3195 if (strcmp(name, XATTR_NAME_SELINUX)) { 3196 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3197 if (rc) 3198 return rc; 3199 3200 /* Not an attribute we recognize, so just check the 3201 ordinary setattr permission. */ 3202 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3203 } 3204 3205 if (!selinux_initialized()) 3206 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); 3207 3208 sbsec = selinux_superblock(inode->i_sb); 3209 if (!(sbsec->flags & SBLABEL_MNT)) 3210 return -EOPNOTSUPP; 3211 3212 if (!inode_owner_or_capable(idmap, inode)) 3213 return -EPERM; 3214 3215 ad.type = LSM_AUDIT_DATA_DENTRY; 3216 ad.u.dentry = dentry; 3217 3218 isec = backing_inode_security(dentry); 3219 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3220 FILE__RELABELFROM, &ad); 3221 if (rc) 3222 return rc; 3223 3224 rc = security_context_to_sid(value, size, &newsid, 3225 GFP_KERNEL); 3226 if (rc == -EINVAL) { 3227 if (!has_cap_mac_admin(true)) { 3228 struct audit_buffer *ab; 3229 size_t audit_size; 3230 3231 /* We strip a nul only if it is at the end, otherwise the 3232 * context contains a nul and we should audit that */ 3233 if (value) { 3234 const char *str = value; 3235 3236 if (str[size - 1] == '\0') 3237 audit_size = size - 1; 3238 else 3239 audit_size = size; 3240 } else { 3241 audit_size = 0; 3242 } 3243 ab = audit_log_start(audit_context(), 3244 GFP_ATOMIC, AUDIT_SELINUX_ERR); 3245 if (!ab) 3246 return rc; 3247 audit_log_format(ab, "op=setxattr invalid_context="); 3248 audit_log_n_untrustedstring(ab, value, audit_size); 3249 audit_log_end(ab); 3250 3251 return rc; 3252 } 3253 rc = security_context_to_sid_force(value, 3254 size, &newsid); 3255 } 3256 if (rc) 3257 return rc; 3258 3259 rc = avc_has_perm(sid, newsid, isec->sclass, 3260 FILE__RELABELTO, &ad); 3261 if (rc) 3262 return rc; 3263 3264 rc = security_validate_transition(isec->sid, newsid, 3265 sid, isec->sclass); 3266 if (rc) 3267 return rc; 3268 3269 return avc_has_perm(newsid, 3270 sbsec->sid, 3271 SECCLASS_FILESYSTEM, 3272 FILESYSTEM__ASSOCIATE, 3273 &ad); 3274 } 3275 3276 static int selinux_inode_set_acl(struct mnt_idmap *idmap, 3277 struct dentry *dentry, const char *acl_name, 3278 struct posix_acl *kacl) 3279 { 3280 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3281 } 3282 3283 static int selinux_inode_get_acl(struct mnt_idmap *idmap, 3284 struct dentry *dentry, const char *acl_name) 3285 { 3286 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); 3287 } 3288 3289 static int selinux_inode_remove_acl(struct mnt_idmap *idmap, 3290 struct dentry *dentry, const char *acl_name) 3291 { 3292 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3293 } 3294 3295 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3296 const void *value, size_t size, 3297 int flags) 3298 { 3299 struct inode *inode = d_backing_inode(dentry); 3300 struct inode_security_struct *isec; 3301 u32 newsid; 3302 int rc; 3303 3304 if (strcmp(name, XATTR_NAME_SELINUX)) { 3305 /* Not an attribute we recognize, so nothing to do. */ 3306 return; 3307 } 3308 3309 if (!selinux_initialized()) { 3310 /* If we haven't even been initialized, then we can't validate 3311 * against a policy, so leave the label as invalid. It may 3312 * resolve to a valid label on the next revalidation try if 3313 * we've since initialized. 3314 */ 3315 return; 3316 } 3317 3318 rc = security_context_to_sid_force(value, size, 3319 &newsid); 3320 if (rc) { 3321 pr_err("SELinux: unable to map context to SID" 3322 "for (%s, %lu), rc=%d\n", 3323 inode->i_sb->s_id, inode->i_ino, -rc); 3324 return; 3325 } 3326 3327 isec = backing_inode_security(dentry); 3328 spin_lock(&isec->lock); 3329 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3330 isec->sid = newsid; 3331 isec->initialized = LABEL_INITIALIZED; 3332 spin_unlock(&isec->lock); 3333 } 3334 3335 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3336 { 3337 const struct cred *cred = current_cred(); 3338 3339 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3340 } 3341 3342 static int selinux_inode_listxattr(struct dentry *dentry) 3343 { 3344 const struct cred *cred = current_cred(); 3345 3346 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3347 } 3348 3349 static int selinux_inode_removexattr(struct mnt_idmap *idmap, 3350 struct dentry *dentry, const char *name) 3351 { 3352 if (strcmp(name, XATTR_NAME_SELINUX)) { 3353 int rc = cap_inode_removexattr(idmap, dentry, name); 3354 if (rc) 3355 return rc; 3356 3357 /* Not an attribute we recognize, so just check the 3358 ordinary setattr permission. */ 3359 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3360 } 3361 3362 if (!selinux_initialized()) 3363 return 0; 3364 3365 /* No one is allowed to remove a SELinux security label. 3366 You can change the label, but all data must be labeled. */ 3367 return -EACCES; 3368 } 3369 3370 static int selinux_path_notify(const struct path *path, u64 mask, 3371 unsigned int obj_type) 3372 { 3373 int ret; 3374 u32 perm; 3375 3376 struct common_audit_data ad; 3377 3378 ad.type = LSM_AUDIT_DATA_PATH; 3379 ad.u.path = *path; 3380 3381 /* 3382 * Set permission needed based on the type of mark being set. 3383 * Performs an additional check for sb watches. 3384 */ 3385 switch (obj_type) { 3386 case FSNOTIFY_OBJ_TYPE_VFSMOUNT: 3387 perm = FILE__WATCH_MOUNT; 3388 break; 3389 case FSNOTIFY_OBJ_TYPE_SB: 3390 perm = FILE__WATCH_SB; 3391 ret = superblock_has_perm(current_cred(), path->dentry->d_sb, 3392 FILESYSTEM__WATCH, &ad); 3393 if (ret) 3394 return ret; 3395 break; 3396 case FSNOTIFY_OBJ_TYPE_INODE: 3397 perm = FILE__WATCH; 3398 break; 3399 default: 3400 return -EINVAL; 3401 } 3402 3403 /* blocking watches require the file:watch_with_perm permission */ 3404 if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) 3405 perm |= FILE__WATCH_WITH_PERM; 3406 3407 /* watches on read-like events need the file:watch_reads permission */ 3408 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) 3409 perm |= FILE__WATCH_READS; 3410 3411 return path_has_perm(current_cred(), path, perm); 3412 } 3413 3414 /* 3415 * Copy the inode security context value to the user. 3416 * 3417 * Permission check is handled by selinux_inode_getxattr hook. 3418 */ 3419 static int selinux_inode_getsecurity(struct mnt_idmap *idmap, 3420 struct inode *inode, const char *name, 3421 void **buffer, bool alloc) 3422 { 3423 u32 size; 3424 int error; 3425 char *context = NULL; 3426 struct inode_security_struct *isec; 3427 3428 /* 3429 * If we're not initialized yet, then we can't validate contexts, so 3430 * just let vfs_getxattr fall back to using the on-disk xattr. 3431 */ 3432 if (!selinux_initialized() || 3433 strcmp(name, XATTR_SELINUX_SUFFIX)) 3434 return -EOPNOTSUPP; 3435 3436 /* 3437 * If the caller has CAP_MAC_ADMIN, then get the raw context 3438 * value even if it is not defined by current policy; otherwise, 3439 * use the in-core value under current policy. 3440 * Use the non-auditing forms of the permission checks since 3441 * getxattr may be called by unprivileged processes commonly 3442 * and lack of permission just means that we fall back to the 3443 * in-core context value, not a denial. 3444 */ 3445 isec = inode_security(inode); 3446 if (has_cap_mac_admin(false)) 3447 error = security_sid_to_context_force(isec->sid, &context, 3448 &size); 3449 else 3450 error = security_sid_to_context(isec->sid, 3451 &context, &size); 3452 if (error) 3453 return error; 3454 error = size; 3455 if (alloc) { 3456 *buffer = context; 3457 goto out_nofree; 3458 } 3459 kfree(context); 3460 out_nofree: 3461 return error; 3462 } 3463 3464 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3465 const void *value, size_t size, int flags) 3466 { 3467 struct inode_security_struct *isec = inode_security_novalidate(inode); 3468 struct superblock_security_struct *sbsec; 3469 u32 newsid; 3470 int rc; 3471 3472 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3473 return -EOPNOTSUPP; 3474 3475 sbsec = selinux_superblock(inode->i_sb); 3476 if (!(sbsec->flags & SBLABEL_MNT)) 3477 return -EOPNOTSUPP; 3478 3479 if (!value || !size) 3480 return -EACCES; 3481 3482 rc = security_context_to_sid(value, size, &newsid, 3483 GFP_KERNEL); 3484 if (rc) 3485 return rc; 3486 3487 spin_lock(&isec->lock); 3488 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3489 isec->sid = newsid; 3490 isec->initialized = LABEL_INITIALIZED; 3491 spin_unlock(&isec->lock); 3492 return 0; 3493 } 3494 3495 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3496 { 3497 const int len = sizeof(XATTR_NAME_SELINUX); 3498 3499 if (!selinux_initialized()) 3500 return 0; 3501 3502 if (buffer && len <= buffer_size) 3503 memcpy(buffer, XATTR_NAME_SELINUX, len); 3504 return len; 3505 } 3506 3507 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3508 { 3509 struct inode_security_struct *isec = inode_security_novalidate(inode); 3510 *secid = isec->sid; 3511 } 3512 3513 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3514 { 3515 u32 sid; 3516 struct task_security_struct *tsec; 3517 struct cred *new_creds = *new; 3518 3519 if (new_creds == NULL) { 3520 new_creds = prepare_creds(); 3521 if (!new_creds) 3522 return -ENOMEM; 3523 } 3524 3525 tsec = selinux_cred(new_creds); 3526 /* Get label from overlay inode and set it in create_sid */ 3527 selinux_inode_getsecid(d_inode(src), &sid); 3528 tsec->create_sid = sid; 3529 *new = new_creds; 3530 return 0; 3531 } 3532 3533 static int selinux_inode_copy_up_xattr(const char *name) 3534 { 3535 /* The copy_up hook above sets the initial context on an inode, but we 3536 * don't then want to overwrite it by blindly copying all the lower 3537 * xattrs up. Instead, filter out SELinux-related xattrs following 3538 * policy load. 3539 */ 3540 if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0) 3541 return 1; /* Discard */ 3542 /* 3543 * Any other attribute apart from SELINUX is not claimed, supported 3544 * by selinux. 3545 */ 3546 return -EOPNOTSUPP; 3547 } 3548 3549 /* kernfs node operations */ 3550 3551 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, 3552 struct kernfs_node *kn) 3553 { 3554 const struct task_security_struct *tsec = selinux_cred(current_cred()); 3555 u32 parent_sid, newsid, clen; 3556 int rc; 3557 char *context; 3558 3559 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); 3560 if (rc == -ENODATA) 3561 return 0; 3562 else if (rc < 0) 3563 return rc; 3564 3565 clen = (u32)rc; 3566 context = kmalloc(clen, GFP_KERNEL); 3567 if (!context) 3568 return -ENOMEM; 3569 3570 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); 3571 if (rc < 0) { 3572 kfree(context); 3573 return rc; 3574 } 3575 3576 rc = security_context_to_sid(context, clen, &parent_sid, 3577 GFP_KERNEL); 3578 kfree(context); 3579 if (rc) 3580 return rc; 3581 3582 if (tsec->create_sid) { 3583 newsid = tsec->create_sid; 3584 } else { 3585 u16 secclass = inode_mode_to_security_class(kn->mode); 3586 struct qstr q; 3587 3588 q.name = kn->name; 3589 q.hash_len = hashlen_string(kn_dir, kn->name); 3590 3591 rc = security_transition_sid(tsec->sid, 3592 parent_sid, secclass, &q, 3593 &newsid); 3594 if (rc) 3595 return rc; 3596 } 3597 3598 rc = security_sid_to_context_force(newsid, 3599 &context, &clen); 3600 if (rc) 3601 return rc; 3602 3603 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, 3604 XATTR_CREATE); 3605 kfree(context); 3606 return rc; 3607 } 3608 3609 3610 /* file security operations */ 3611 3612 static int selinux_revalidate_file_permission(struct file *file, int mask) 3613 { 3614 const struct cred *cred = current_cred(); 3615 struct inode *inode = file_inode(file); 3616 3617 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3618 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3619 mask |= MAY_APPEND; 3620 3621 return file_has_perm(cred, file, 3622 file_mask_to_av(inode->i_mode, mask)); 3623 } 3624 3625 static int selinux_file_permission(struct file *file, int mask) 3626 { 3627 struct inode *inode = file_inode(file); 3628 struct file_security_struct *fsec = selinux_file(file); 3629 struct inode_security_struct *isec; 3630 u32 sid = current_sid(); 3631 3632 if (!mask) 3633 /* No permission to check. Existence test. */ 3634 return 0; 3635 3636 isec = inode_security(inode); 3637 if (sid == fsec->sid && fsec->isid == isec->sid && 3638 fsec->pseqno == avc_policy_seqno()) 3639 /* No change since file_open check. */ 3640 return 0; 3641 3642 return selinux_revalidate_file_permission(file, mask); 3643 } 3644 3645 static int selinux_file_alloc_security(struct file *file) 3646 { 3647 struct file_security_struct *fsec = selinux_file(file); 3648 u32 sid = current_sid(); 3649 3650 fsec->sid = sid; 3651 fsec->fown_sid = sid; 3652 3653 return 0; 3654 } 3655 3656 /* 3657 * Check whether a task has the ioctl permission and cmd 3658 * operation to an inode. 3659 */ 3660 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3661 u32 requested, u16 cmd) 3662 { 3663 struct common_audit_data ad; 3664 struct file_security_struct *fsec = selinux_file(file); 3665 struct inode *inode = file_inode(file); 3666 struct inode_security_struct *isec; 3667 struct lsm_ioctlop_audit ioctl; 3668 u32 ssid = cred_sid(cred); 3669 int rc; 3670 u8 driver = cmd >> 8; 3671 u8 xperm = cmd & 0xff; 3672 3673 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3674 ad.u.op = &ioctl; 3675 ad.u.op->cmd = cmd; 3676 ad.u.op->path = file->f_path; 3677 3678 if (ssid != fsec->sid) { 3679 rc = avc_has_perm(ssid, fsec->sid, 3680 SECCLASS_FD, 3681 FD__USE, 3682 &ad); 3683 if (rc) 3684 goto out; 3685 } 3686 3687 if (unlikely(IS_PRIVATE(inode))) 3688 return 0; 3689 3690 isec = inode_security(inode); 3691 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3692 requested, driver, xperm, &ad); 3693 out: 3694 return rc; 3695 } 3696 3697 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3698 unsigned long arg) 3699 { 3700 const struct cred *cred = current_cred(); 3701 int error = 0; 3702 3703 switch (cmd) { 3704 case FIONREAD: 3705 case FIBMAP: 3706 case FIGETBSZ: 3707 case FS_IOC_GETFLAGS: 3708 case FS_IOC_GETVERSION: 3709 error = file_has_perm(cred, file, FILE__GETATTR); 3710 break; 3711 3712 case FS_IOC_SETFLAGS: 3713 case FS_IOC_SETVERSION: 3714 error = file_has_perm(cred, file, FILE__SETATTR); 3715 break; 3716 3717 /* sys_ioctl() checks */ 3718 case FIONBIO: 3719 case FIOASYNC: 3720 error = file_has_perm(cred, file, 0); 3721 break; 3722 3723 case KDSKBENT: 3724 case KDSKBSENT: 3725 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3726 CAP_OPT_NONE, true); 3727 break; 3728 3729 case FIOCLEX: 3730 case FIONCLEX: 3731 if (!selinux_policycap_ioctl_skip_cloexec()) 3732 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3733 break; 3734 3735 /* default case assumes that the command will go 3736 * to the file's ioctl() function. 3737 */ 3738 default: 3739 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3740 } 3741 return error; 3742 } 3743 3744 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd, 3745 unsigned long arg) 3746 { 3747 /* 3748 * If we are in a 64-bit kernel running 32-bit userspace, we need to 3749 * make sure we don't compare 32-bit flags to 64-bit flags. 3750 */ 3751 switch (cmd) { 3752 case FS_IOC32_GETFLAGS: 3753 cmd = FS_IOC_GETFLAGS; 3754 break; 3755 case FS_IOC32_SETFLAGS: 3756 cmd = FS_IOC_SETFLAGS; 3757 break; 3758 case FS_IOC32_GETVERSION: 3759 cmd = FS_IOC_GETVERSION; 3760 break; 3761 case FS_IOC32_SETVERSION: 3762 cmd = FS_IOC_SETVERSION; 3763 break; 3764 default: 3765 break; 3766 } 3767 3768 return selinux_file_ioctl(file, cmd, arg); 3769 } 3770 3771 static int default_noexec __ro_after_init; 3772 3773 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3774 { 3775 const struct cred *cred = current_cred(); 3776 u32 sid = cred_sid(cred); 3777 int rc = 0; 3778 3779 if (default_noexec && 3780 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3781 (!shared && (prot & PROT_WRITE)))) { 3782 /* 3783 * We are making executable an anonymous mapping or a 3784 * private file mapping that will also be writable. 3785 * This has an additional check. 3786 */ 3787 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3788 PROCESS__EXECMEM, NULL); 3789 if (rc) 3790 goto error; 3791 } 3792 3793 if (file) { 3794 /* read access is always possible with a mapping */ 3795 u32 av = FILE__READ; 3796 3797 /* write access only matters if the mapping is shared */ 3798 if (shared && (prot & PROT_WRITE)) 3799 av |= FILE__WRITE; 3800 3801 if (prot & PROT_EXEC) 3802 av |= FILE__EXECUTE; 3803 3804 return file_has_perm(cred, file, av); 3805 } 3806 3807 error: 3808 return rc; 3809 } 3810 3811 static int selinux_mmap_addr(unsigned long addr) 3812 { 3813 int rc = 0; 3814 3815 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3816 u32 sid = current_sid(); 3817 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3818 MEMPROTECT__MMAP_ZERO, NULL); 3819 } 3820 3821 return rc; 3822 } 3823 3824 static int selinux_mmap_file(struct file *file, 3825 unsigned long reqprot __always_unused, 3826 unsigned long prot, unsigned long flags) 3827 { 3828 struct common_audit_data ad; 3829 int rc; 3830 3831 if (file) { 3832 ad.type = LSM_AUDIT_DATA_FILE; 3833 ad.u.file = file; 3834 rc = inode_has_perm(current_cred(), file_inode(file), 3835 FILE__MAP, &ad); 3836 if (rc) 3837 return rc; 3838 } 3839 3840 return file_map_prot_check(file, prot, 3841 (flags & MAP_TYPE) == MAP_SHARED); 3842 } 3843 3844 static int selinux_file_mprotect(struct vm_area_struct *vma, 3845 unsigned long reqprot __always_unused, 3846 unsigned long prot) 3847 { 3848 const struct cred *cred = current_cred(); 3849 u32 sid = cred_sid(cred); 3850 3851 if (default_noexec && 3852 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3853 int rc = 0; 3854 if (vma_is_initial_heap(vma)) { 3855 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3856 PROCESS__EXECHEAP, NULL); 3857 } else if (!vma->vm_file && (vma_is_initial_stack(vma) || 3858 vma_is_stack_for_current(vma))) { 3859 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, 3860 PROCESS__EXECSTACK, NULL); 3861 } else if (vma->vm_file && vma->anon_vma) { 3862 /* 3863 * We are making executable a file mapping that has 3864 * had some COW done. Since pages might have been 3865 * written, check ability to execute the possibly 3866 * modified content. This typically should only 3867 * occur for text relocations. 3868 */ 3869 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3870 } 3871 if (rc) 3872 return rc; 3873 } 3874 3875 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3876 } 3877 3878 static int selinux_file_lock(struct file *file, unsigned int cmd) 3879 { 3880 const struct cred *cred = current_cred(); 3881 3882 return file_has_perm(cred, file, FILE__LOCK); 3883 } 3884 3885 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3886 unsigned long arg) 3887 { 3888 const struct cred *cred = current_cred(); 3889 int err = 0; 3890 3891 switch (cmd) { 3892 case F_SETFL: 3893 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3894 err = file_has_perm(cred, file, FILE__WRITE); 3895 break; 3896 } 3897 fallthrough; 3898 case F_SETOWN: 3899 case F_SETSIG: 3900 case F_GETFL: 3901 case F_GETOWN: 3902 case F_GETSIG: 3903 case F_GETOWNER_UIDS: 3904 /* Just check FD__USE permission */ 3905 err = file_has_perm(cred, file, 0); 3906 break; 3907 case F_GETLK: 3908 case F_SETLK: 3909 case F_SETLKW: 3910 case F_OFD_GETLK: 3911 case F_OFD_SETLK: 3912 case F_OFD_SETLKW: 3913 #if BITS_PER_LONG == 32 3914 case F_GETLK64: 3915 case F_SETLK64: 3916 case F_SETLKW64: 3917 #endif 3918 err = file_has_perm(cred, file, FILE__LOCK); 3919 break; 3920 } 3921 3922 return err; 3923 } 3924 3925 static void selinux_file_set_fowner(struct file *file) 3926 { 3927 struct file_security_struct *fsec; 3928 3929 fsec = selinux_file(file); 3930 fsec->fown_sid = current_sid(); 3931 } 3932 3933 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3934 struct fown_struct *fown, int signum) 3935 { 3936 struct file *file; 3937 u32 sid = task_sid_obj(tsk); 3938 u32 perm; 3939 struct file_security_struct *fsec; 3940 3941 /* struct fown_struct is never outside the context of a struct file */ 3942 file = container_of(fown, struct file, f_owner); 3943 3944 fsec = selinux_file(file); 3945 3946 if (!signum) 3947 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3948 else 3949 perm = signal_to_av(signum); 3950 3951 return avc_has_perm(fsec->fown_sid, sid, 3952 SECCLASS_PROCESS, perm, NULL); 3953 } 3954 3955 static int selinux_file_receive(struct file *file) 3956 { 3957 const struct cred *cred = current_cred(); 3958 3959 return file_has_perm(cred, file, file_to_av(file)); 3960 } 3961 3962 static int selinux_file_open(struct file *file) 3963 { 3964 struct file_security_struct *fsec; 3965 struct inode_security_struct *isec; 3966 3967 fsec = selinux_file(file); 3968 isec = inode_security(file_inode(file)); 3969 /* 3970 * Save inode label and policy sequence number 3971 * at open-time so that selinux_file_permission 3972 * can determine whether revalidation is necessary. 3973 * Task label is already saved in the file security 3974 * struct as its SID. 3975 */ 3976 fsec->isid = isec->sid; 3977 fsec->pseqno = avc_policy_seqno(); 3978 /* 3979 * Since the inode label or policy seqno may have changed 3980 * between the selinux_inode_permission check and the saving 3981 * of state above, recheck that access is still permitted. 3982 * Otherwise, access might never be revalidated against the 3983 * new inode label or new policy. 3984 * This check is not redundant - do not remove. 3985 */ 3986 return file_path_has_perm(file->f_cred, file, open_file_to_av(file)); 3987 } 3988 3989 /* task security operations */ 3990 3991 static int selinux_task_alloc(struct task_struct *task, 3992 unsigned long clone_flags) 3993 { 3994 u32 sid = current_sid(); 3995 3996 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3997 } 3998 3999 /* 4000 * prepare a new set of credentials for modification 4001 */ 4002 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 4003 gfp_t gfp) 4004 { 4005 const struct task_security_struct *old_tsec = selinux_cred(old); 4006 struct task_security_struct *tsec = selinux_cred(new); 4007 4008 *tsec = *old_tsec; 4009 return 0; 4010 } 4011 4012 /* 4013 * transfer the SELinux data to a blank set of creds 4014 */ 4015 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 4016 { 4017 const struct task_security_struct *old_tsec = selinux_cred(old); 4018 struct task_security_struct *tsec = selinux_cred(new); 4019 4020 *tsec = *old_tsec; 4021 } 4022 4023 static void selinux_cred_getsecid(const struct cred *c, u32 *secid) 4024 { 4025 *secid = cred_sid(c); 4026 } 4027 4028 /* 4029 * set the security data for a kernel service 4030 * - all the creation contexts are set to unlabelled 4031 */ 4032 static int selinux_kernel_act_as(struct cred *new, u32 secid) 4033 { 4034 struct task_security_struct *tsec = selinux_cred(new); 4035 u32 sid = current_sid(); 4036 int ret; 4037 4038 ret = avc_has_perm(sid, secid, 4039 SECCLASS_KERNEL_SERVICE, 4040 KERNEL_SERVICE__USE_AS_OVERRIDE, 4041 NULL); 4042 if (ret == 0) { 4043 tsec->sid = secid; 4044 tsec->create_sid = 0; 4045 tsec->keycreate_sid = 0; 4046 tsec->sockcreate_sid = 0; 4047 } 4048 return ret; 4049 } 4050 4051 /* 4052 * set the file creation context in a security record to the same as the 4053 * objective context of the specified inode 4054 */ 4055 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 4056 { 4057 struct inode_security_struct *isec = inode_security(inode); 4058 struct task_security_struct *tsec = selinux_cred(new); 4059 u32 sid = current_sid(); 4060 int ret; 4061 4062 ret = avc_has_perm(sid, isec->sid, 4063 SECCLASS_KERNEL_SERVICE, 4064 KERNEL_SERVICE__CREATE_FILES_AS, 4065 NULL); 4066 4067 if (ret == 0) 4068 tsec->create_sid = isec->sid; 4069 return ret; 4070 } 4071 4072 static int selinux_kernel_module_request(char *kmod_name) 4073 { 4074 struct common_audit_data ad; 4075 4076 ad.type = LSM_AUDIT_DATA_KMOD; 4077 ad.u.kmod_name = kmod_name; 4078 4079 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4080 SYSTEM__MODULE_REQUEST, &ad); 4081 } 4082 4083 static int selinux_kernel_module_from_file(struct file *file) 4084 { 4085 struct common_audit_data ad; 4086 struct inode_security_struct *isec; 4087 struct file_security_struct *fsec; 4088 u32 sid = current_sid(); 4089 int rc; 4090 4091 /* init_module */ 4092 if (file == NULL) 4093 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 4094 SYSTEM__MODULE_LOAD, NULL); 4095 4096 /* finit_module */ 4097 4098 ad.type = LSM_AUDIT_DATA_FILE; 4099 ad.u.file = file; 4100 4101 fsec = selinux_file(file); 4102 if (sid != fsec->sid) { 4103 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4104 if (rc) 4105 return rc; 4106 } 4107 4108 isec = inode_security(file_inode(file)); 4109 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 4110 SYSTEM__MODULE_LOAD, &ad); 4111 } 4112 4113 static int selinux_kernel_read_file(struct file *file, 4114 enum kernel_read_file_id id, 4115 bool contents) 4116 { 4117 int rc = 0; 4118 4119 switch (id) { 4120 case READING_MODULE: 4121 rc = selinux_kernel_module_from_file(contents ? file : NULL); 4122 break; 4123 default: 4124 break; 4125 } 4126 4127 return rc; 4128 } 4129 4130 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) 4131 { 4132 int rc = 0; 4133 4134 switch (id) { 4135 case LOADING_MODULE: 4136 rc = selinux_kernel_module_from_file(NULL); 4137 break; 4138 default: 4139 break; 4140 } 4141 4142 return rc; 4143 } 4144 4145 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4146 { 4147 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4148 PROCESS__SETPGID, NULL); 4149 } 4150 4151 static int selinux_task_getpgid(struct task_struct *p) 4152 { 4153 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4154 PROCESS__GETPGID, NULL); 4155 } 4156 4157 static int selinux_task_getsid(struct task_struct *p) 4158 { 4159 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4160 PROCESS__GETSESSION, NULL); 4161 } 4162 4163 static void selinux_current_getsecid_subj(u32 *secid) 4164 { 4165 *secid = current_sid(); 4166 } 4167 4168 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) 4169 { 4170 *secid = task_sid_obj(p); 4171 } 4172 4173 static int selinux_task_setnice(struct task_struct *p, int nice) 4174 { 4175 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4176 PROCESS__SETSCHED, NULL); 4177 } 4178 4179 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4180 { 4181 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4182 PROCESS__SETSCHED, NULL); 4183 } 4184 4185 static int selinux_task_getioprio(struct task_struct *p) 4186 { 4187 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4188 PROCESS__GETSCHED, NULL); 4189 } 4190 4191 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4192 unsigned int flags) 4193 { 4194 u32 av = 0; 4195 4196 if (!flags) 4197 return 0; 4198 if (flags & LSM_PRLIMIT_WRITE) 4199 av |= PROCESS__SETRLIMIT; 4200 if (flags & LSM_PRLIMIT_READ) 4201 av |= PROCESS__GETRLIMIT; 4202 return avc_has_perm(cred_sid(cred), cred_sid(tcred), 4203 SECCLASS_PROCESS, av, NULL); 4204 } 4205 4206 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4207 struct rlimit *new_rlim) 4208 { 4209 struct rlimit *old_rlim = p->signal->rlim + resource; 4210 4211 /* Control the ability to change the hard limit (whether 4212 lowering or raising it), so that the hard limit can 4213 later be used as a safe reset point for the soft limit 4214 upon context transitions. See selinux_bprm_committing_creds. */ 4215 if (old_rlim->rlim_max != new_rlim->rlim_max) 4216 return avc_has_perm(current_sid(), task_sid_obj(p), 4217 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4218 4219 return 0; 4220 } 4221 4222 static int selinux_task_setscheduler(struct task_struct *p) 4223 { 4224 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4225 PROCESS__SETSCHED, NULL); 4226 } 4227 4228 static int selinux_task_getscheduler(struct task_struct *p) 4229 { 4230 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4231 PROCESS__GETSCHED, NULL); 4232 } 4233 4234 static int selinux_task_movememory(struct task_struct *p) 4235 { 4236 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, 4237 PROCESS__SETSCHED, NULL); 4238 } 4239 4240 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, 4241 int sig, const struct cred *cred) 4242 { 4243 u32 secid; 4244 u32 perm; 4245 4246 if (!sig) 4247 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4248 else 4249 perm = signal_to_av(sig); 4250 if (!cred) 4251 secid = current_sid(); 4252 else 4253 secid = cred_sid(cred); 4254 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); 4255 } 4256 4257 static void selinux_task_to_inode(struct task_struct *p, 4258 struct inode *inode) 4259 { 4260 struct inode_security_struct *isec = selinux_inode(inode); 4261 u32 sid = task_sid_obj(p); 4262 4263 spin_lock(&isec->lock); 4264 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4265 isec->sid = sid; 4266 isec->initialized = LABEL_INITIALIZED; 4267 spin_unlock(&isec->lock); 4268 } 4269 4270 static int selinux_userns_create(const struct cred *cred) 4271 { 4272 u32 sid = current_sid(); 4273 4274 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, 4275 USER_NAMESPACE__CREATE, NULL); 4276 } 4277 4278 /* Returns error only if unable to parse addresses */ 4279 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4280 struct common_audit_data *ad, u8 *proto) 4281 { 4282 int offset, ihlen, ret = -EINVAL; 4283 struct iphdr _iph, *ih; 4284 4285 offset = skb_network_offset(skb); 4286 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4287 if (ih == NULL) 4288 goto out; 4289 4290 ihlen = ih->ihl * 4; 4291 if (ihlen < sizeof(_iph)) 4292 goto out; 4293 4294 ad->u.net->v4info.saddr = ih->saddr; 4295 ad->u.net->v4info.daddr = ih->daddr; 4296 ret = 0; 4297 4298 if (proto) 4299 *proto = ih->protocol; 4300 4301 switch (ih->protocol) { 4302 case IPPROTO_TCP: { 4303 struct tcphdr _tcph, *th; 4304 4305 if (ntohs(ih->frag_off) & IP_OFFSET) 4306 break; 4307 4308 offset += ihlen; 4309 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4310 if (th == NULL) 4311 break; 4312 4313 ad->u.net->sport = th->source; 4314 ad->u.net->dport = th->dest; 4315 break; 4316 } 4317 4318 case IPPROTO_UDP: { 4319 struct udphdr _udph, *uh; 4320 4321 if (ntohs(ih->frag_off) & IP_OFFSET) 4322 break; 4323 4324 offset += ihlen; 4325 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4326 if (uh == NULL) 4327 break; 4328 4329 ad->u.net->sport = uh->source; 4330 ad->u.net->dport = uh->dest; 4331 break; 4332 } 4333 4334 case IPPROTO_DCCP: { 4335 struct dccp_hdr _dccph, *dh; 4336 4337 if (ntohs(ih->frag_off) & IP_OFFSET) 4338 break; 4339 4340 offset += ihlen; 4341 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4342 if (dh == NULL) 4343 break; 4344 4345 ad->u.net->sport = dh->dccph_sport; 4346 ad->u.net->dport = dh->dccph_dport; 4347 break; 4348 } 4349 4350 #if IS_ENABLED(CONFIG_IP_SCTP) 4351 case IPPROTO_SCTP: { 4352 struct sctphdr _sctph, *sh; 4353 4354 if (ntohs(ih->frag_off) & IP_OFFSET) 4355 break; 4356 4357 offset += ihlen; 4358 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4359 if (sh == NULL) 4360 break; 4361 4362 ad->u.net->sport = sh->source; 4363 ad->u.net->dport = sh->dest; 4364 break; 4365 } 4366 #endif 4367 default: 4368 break; 4369 } 4370 out: 4371 return ret; 4372 } 4373 4374 #if IS_ENABLED(CONFIG_IPV6) 4375 4376 /* Returns error only if unable to parse addresses */ 4377 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4378 struct common_audit_data *ad, u8 *proto) 4379 { 4380 u8 nexthdr; 4381 int ret = -EINVAL, offset; 4382 struct ipv6hdr _ipv6h, *ip6; 4383 __be16 frag_off; 4384 4385 offset = skb_network_offset(skb); 4386 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4387 if (ip6 == NULL) 4388 goto out; 4389 4390 ad->u.net->v6info.saddr = ip6->saddr; 4391 ad->u.net->v6info.daddr = ip6->daddr; 4392 ret = 0; 4393 4394 nexthdr = ip6->nexthdr; 4395 offset += sizeof(_ipv6h); 4396 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4397 if (offset < 0) 4398 goto out; 4399 4400 if (proto) 4401 *proto = nexthdr; 4402 4403 switch (nexthdr) { 4404 case IPPROTO_TCP: { 4405 struct tcphdr _tcph, *th; 4406 4407 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4408 if (th == NULL) 4409 break; 4410 4411 ad->u.net->sport = th->source; 4412 ad->u.net->dport = th->dest; 4413 break; 4414 } 4415 4416 case IPPROTO_UDP: { 4417 struct udphdr _udph, *uh; 4418 4419 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4420 if (uh == NULL) 4421 break; 4422 4423 ad->u.net->sport = uh->source; 4424 ad->u.net->dport = uh->dest; 4425 break; 4426 } 4427 4428 case IPPROTO_DCCP: { 4429 struct dccp_hdr _dccph, *dh; 4430 4431 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4432 if (dh == NULL) 4433 break; 4434 4435 ad->u.net->sport = dh->dccph_sport; 4436 ad->u.net->dport = dh->dccph_dport; 4437 break; 4438 } 4439 4440 #if IS_ENABLED(CONFIG_IP_SCTP) 4441 case IPPROTO_SCTP: { 4442 struct sctphdr _sctph, *sh; 4443 4444 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4445 if (sh == NULL) 4446 break; 4447 4448 ad->u.net->sport = sh->source; 4449 ad->u.net->dport = sh->dest; 4450 break; 4451 } 4452 #endif 4453 /* includes fragments */ 4454 default: 4455 break; 4456 } 4457 out: 4458 return ret; 4459 } 4460 4461 #endif /* IPV6 */ 4462 4463 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4464 char **_addrp, int src, u8 *proto) 4465 { 4466 char *addrp; 4467 int ret; 4468 4469 switch (ad->u.net->family) { 4470 case PF_INET: 4471 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4472 if (ret) 4473 goto parse_error; 4474 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4475 &ad->u.net->v4info.daddr); 4476 goto okay; 4477 4478 #if IS_ENABLED(CONFIG_IPV6) 4479 case PF_INET6: 4480 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4481 if (ret) 4482 goto parse_error; 4483 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4484 &ad->u.net->v6info.daddr); 4485 goto okay; 4486 #endif /* IPV6 */ 4487 default: 4488 addrp = NULL; 4489 goto okay; 4490 } 4491 4492 parse_error: 4493 pr_warn( 4494 "SELinux: failure in selinux_parse_skb()," 4495 " unable to parse packet\n"); 4496 return ret; 4497 4498 okay: 4499 if (_addrp) 4500 *_addrp = addrp; 4501 return 0; 4502 } 4503 4504 /** 4505 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4506 * @skb: the packet 4507 * @family: protocol family 4508 * @sid: the packet's peer label SID 4509 * 4510 * Description: 4511 * Check the various different forms of network peer labeling and determine 4512 * the peer label/SID for the packet; most of the magic actually occurs in 4513 * the security server function security_net_peersid_cmp(). The function 4514 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4515 * or -EACCES if @sid is invalid due to inconsistencies with the different 4516 * peer labels. 4517 * 4518 */ 4519 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4520 { 4521 int err; 4522 u32 xfrm_sid; 4523 u32 nlbl_sid; 4524 u32 nlbl_type; 4525 4526 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4527 if (unlikely(err)) 4528 return -EACCES; 4529 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4530 if (unlikely(err)) 4531 return -EACCES; 4532 4533 err = security_net_peersid_resolve(nlbl_sid, 4534 nlbl_type, xfrm_sid, sid); 4535 if (unlikely(err)) { 4536 pr_warn( 4537 "SELinux: failure in selinux_skb_peerlbl_sid()," 4538 " unable to determine packet's peer label\n"); 4539 return -EACCES; 4540 } 4541 4542 return 0; 4543 } 4544 4545 /** 4546 * selinux_conn_sid - Determine the child socket label for a connection 4547 * @sk_sid: the parent socket's SID 4548 * @skb_sid: the packet's SID 4549 * @conn_sid: the resulting connection SID 4550 * 4551 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4552 * combined with the MLS information from @skb_sid in order to create 4553 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy 4554 * of @sk_sid. Returns zero on success, negative values on failure. 4555 * 4556 */ 4557 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4558 { 4559 int err = 0; 4560 4561 if (skb_sid != SECSID_NULL) 4562 err = security_sid_mls_copy(sk_sid, skb_sid, 4563 conn_sid); 4564 else 4565 *conn_sid = sk_sid; 4566 4567 return err; 4568 } 4569 4570 /* socket security operations */ 4571 4572 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4573 u16 secclass, u32 *socksid) 4574 { 4575 if (tsec->sockcreate_sid > SECSID_NULL) { 4576 *socksid = tsec->sockcreate_sid; 4577 return 0; 4578 } 4579 4580 return security_transition_sid(tsec->sid, tsec->sid, 4581 secclass, NULL, socksid); 4582 } 4583 4584 static int sock_has_perm(struct sock *sk, u32 perms) 4585 { 4586 struct sk_security_struct *sksec = sk->sk_security; 4587 struct common_audit_data ad; 4588 struct lsm_network_audit net; 4589 4590 if (sksec->sid == SECINITSID_KERNEL) 4591 return 0; 4592 4593 /* 4594 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that 4595 * inherited the kernel context from early boot used to be skipped 4596 * here, so preserve that behavior unless the capability is set. 4597 * 4598 * By setting the capability the policy signals that it is ready 4599 * for this quirk to be fixed. Note that sockets created by a kernel 4600 * thread or a usermode helper executed without a transition will 4601 * still be skipped in this check regardless of the policycap 4602 * setting. 4603 */ 4604 if (!selinux_policycap_userspace_initial_context() && 4605 sksec->sid == SECINITSID_INIT) 4606 return 0; 4607 4608 ad_net_init_from_sk(&ad, &net, sk); 4609 4610 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, 4611 &ad); 4612 } 4613 4614 static int selinux_socket_create(int family, int type, 4615 int protocol, int kern) 4616 { 4617 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4618 u32 newsid; 4619 u16 secclass; 4620 int rc; 4621 4622 if (kern) 4623 return 0; 4624 4625 secclass = socket_type_to_security_class(family, type, protocol); 4626 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4627 if (rc) 4628 return rc; 4629 4630 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4631 } 4632 4633 static int selinux_socket_post_create(struct socket *sock, int family, 4634 int type, int protocol, int kern) 4635 { 4636 const struct task_security_struct *tsec = selinux_cred(current_cred()); 4637 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4638 struct sk_security_struct *sksec; 4639 u16 sclass = socket_type_to_security_class(family, type, protocol); 4640 u32 sid = SECINITSID_KERNEL; 4641 int err = 0; 4642 4643 if (!kern) { 4644 err = socket_sockcreate_sid(tsec, sclass, &sid); 4645 if (err) 4646 return err; 4647 } 4648 4649 isec->sclass = sclass; 4650 isec->sid = sid; 4651 isec->initialized = LABEL_INITIALIZED; 4652 4653 if (sock->sk) { 4654 sksec = sock->sk->sk_security; 4655 sksec->sclass = sclass; 4656 sksec->sid = sid; 4657 /* Allows detection of the first association on this socket */ 4658 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4659 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4660 4661 err = selinux_netlbl_socket_post_create(sock->sk, family); 4662 } 4663 4664 return err; 4665 } 4666 4667 static int selinux_socket_socketpair(struct socket *socka, 4668 struct socket *sockb) 4669 { 4670 struct sk_security_struct *sksec_a = socka->sk->sk_security; 4671 struct sk_security_struct *sksec_b = sockb->sk->sk_security; 4672 4673 sksec_a->peer_sid = sksec_b->sid; 4674 sksec_b->peer_sid = sksec_a->sid; 4675 4676 return 0; 4677 } 4678 4679 /* Range of port numbers used to automatically bind. 4680 Need to determine whether we should perform a name_bind 4681 permission check between the socket and the port number. */ 4682 4683 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4684 { 4685 struct sock *sk = sock->sk; 4686 struct sk_security_struct *sksec = sk->sk_security; 4687 u16 family; 4688 int err; 4689 4690 err = sock_has_perm(sk, SOCKET__BIND); 4691 if (err) 4692 goto out; 4693 4694 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4695 family = sk->sk_family; 4696 if (family == PF_INET || family == PF_INET6) { 4697 char *addrp; 4698 struct common_audit_data ad; 4699 struct lsm_network_audit net = {0,}; 4700 struct sockaddr_in *addr4 = NULL; 4701 struct sockaddr_in6 *addr6 = NULL; 4702 u16 family_sa; 4703 unsigned short snum; 4704 u32 sid, node_perm; 4705 4706 /* 4707 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4708 * that validates multiple binding addresses. Because of this 4709 * need to check address->sa_family as it is possible to have 4710 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4711 */ 4712 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4713 return -EINVAL; 4714 family_sa = address->sa_family; 4715 switch (family_sa) { 4716 case AF_UNSPEC: 4717 case AF_INET: 4718 if (addrlen < sizeof(struct sockaddr_in)) 4719 return -EINVAL; 4720 addr4 = (struct sockaddr_in *)address; 4721 if (family_sa == AF_UNSPEC) { 4722 if (family == PF_INET6) { 4723 /* Length check from inet6_bind_sk() */ 4724 if (addrlen < SIN6_LEN_RFC2133) 4725 return -EINVAL; 4726 /* Family check from __inet6_bind() */ 4727 goto err_af; 4728 } 4729 /* see __inet_bind(), we only want to allow 4730 * AF_UNSPEC if the address is INADDR_ANY 4731 */ 4732 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) 4733 goto err_af; 4734 family_sa = AF_INET; 4735 } 4736 snum = ntohs(addr4->sin_port); 4737 addrp = (char *)&addr4->sin_addr.s_addr; 4738 break; 4739 case AF_INET6: 4740 if (addrlen < SIN6_LEN_RFC2133) 4741 return -EINVAL; 4742 addr6 = (struct sockaddr_in6 *)address; 4743 snum = ntohs(addr6->sin6_port); 4744 addrp = (char *)&addr6->sin6_addr.s6_addr; 4745 break; 4746 default: 4747 goto err_af; 4748 } 4749 4750 ad.type = LSM_AUDIT_DATA_NET; 4751 ad.u.net = &net; 4752 ad.u.net->sport = htons(snum); 4753 ad.u.net->family = family_sa; 4754 4755 if (snum) { 4756 int low, high; 4757 4758 inet_get_local_port_range(sock_net(sk), &low, &high); 4759 4760 if (inet_port_requires_bind_service(sock_net(sk), snum) || 4761 snum < low || snum > high) { 4762 err = sel_netport_sid(sk->sk_protocol, 4763 snum, &sid); 4764 if (err) 4765 goto out; 4766 err = avc_has_perm(sksec->sid, sid, 4767 sksec->sclass, 4768 SOCKET__NAME_BIND, &ad); 4769 if (err) 4770 goto out; 4771 } 4772 } 4773 4774 switch (sksec->sclass) { 4775 case SECCLASS_TCP_SOCKET: 4776 node_perm = TCP_SOCKET__NODE_BIND; 4777 break; 4778 4779 case SECCLASS_UDP_SOCKET: 4780 node_perm = UDP_SOCKET__NODE_BIND; 4781 break; 4782 4783 case SECCLASS_DCCP_SOCKET: 4784 node_perm = DCCP_SOCKET__NODE_BIND; 4785 break; 4786 4787 case SECCLASS_SCTP_SOCKET: 4788 node_perm = SCTP_SOCKET__NODE_BIND; 4789 break; 4790 4791 default: 4792 node_perm = RAWIP_SOCKET__NODE_BIND; 4793 break; 4794 } 4795 4796 err = sel_netnode_sid(addrp, family_sa, &sid); 4797 if (err) 4798 goto out; 4799 4800 if (family_sa == AF_INET) 4801 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4802 else 4803 ad.u.net->v6info.saddr = addr6->sin6_addr; 4804 4805 err = avc_has_perm(sksec->sid, sid, 4806 sksec->sclass, node_perm, &ad); 4807 if (err) 4808 goto out; 4809 } 4810 out: 4811 return err; 4812 err_af: 4813 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ 4814 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4815 return -EINVAL; 4816 return -EAFNOSUPPORT; 4817 } 4818 4819 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4820 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst 4821 */ 4822 static int selinux_socket_connect_helper(struct socket *sock, 4823 struct sockaddr *address, int addrlen) 4824 { 4825 struct sock *sk = sock->sk; 4826 struct sk_security_struct *sksec = sk->sk_security; 4827 int err; 4828 4829 err = sock_has_perm(sk, SOCKET__CONNECT); 4830 if (err) 4831 return err; 4832 if (addrlen < offsetofend(struct sockaddr, sa_family)) 4833 return -EINVAL; 4834 4835 /* connect(AF_UNSPEC) has special handling, as it is a documented 4836 * way to disconnect the socket 4837 */ 4838 if (address->sa_family == AF_UNSPEC) 4839 return 0; 4840 4841 /* 4842 * If a TCP, DCCP or SCTP socket, check name_connect permission 4843 * for the port. 4844 */ 4845 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4846 sksec->sclass == SECCLASS_DCCP_SOCKET || 4847 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4848 struct common_audit_data ad; 4849 struct lsm_network_audit net = {0,}; 4850 struct sockaddr_in *addr4 = NULL; 4851 struct sockaddr_in6 *addr6 = NULL; 4852 unsigned short snum; 4853 u32 sid, perm; 4854 4855 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4856 * that validates multiple connect addresses. Because of this 4857 * need to check address->sa_family as it is possible to have 4858 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4859 */ 4860 switch (address->sa_family) { 4861 case AF_INET: 4862 addr4 = (struct sockaddr_in *)address; 4863 if (addrlen < sizeof(struct sockaddr_in)) 4864 return -EINVAL; 4865 snum = ntohs(addr4->sin_port); 4866 break; 4867 case AF_INET6: 4868 addr6 = (struct sockaddr_in6 *)address; 4869 if (addrlen < SIN6_LEN_RFC2133) 4870 return -EINVAL; 4871 snum = ntohs(addr6->sin6_port); 4872 break; 4873 default: 4874 /* Note that SCTP services expect -EINVAL, whereas 4875 * others expect -EAFNOSUPPORT. 4876 */ 4877 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4878 return -EINVAL; 4879 else 4880 return -EAFNOSUPPORT; 4881 } 4882 4883 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4884 if (err) 4885 return err; 4886 4887 switch (sksec->sclass) { 4888 case SECCLASS_TCP_SOCKET: 4889 perm = TCP_SOCKET__NAME_CONNECT; 4890 break; 4891 case SECCLASS_DCCP_SOCKET: 4892 perm = DCCP_SOCKET__NAME_CONNECT; 4893 break; 4894 case SECCLASS_SCTP_SOCKET: 4895 perm = SCTP_SOCKET__NAME_CONNECT; 4896 break; 4897 } 4898 4899 ad.type = LSM_AUDIT_DATA_NET; 4900 ad.u.net = &net; 4901 ad.u.net->dport = htons(snum); 4902 ad.u.net->family = address->sa_family; 4903 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4904 if (err) 4905 return err; 4906 } 4907 4908 return 0; 4909 } 4910 4911 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4912 static int selinux_socket_connect(struct socket *sock, 4913 struct sockaddr *address, int addrlen) 4914 { 4915 int err; 4916 struct sock *sk = sock->sk; 4917 4918 err = selinux_socket_connect_helper(sock, address, addrlen); 4919 if (err) 4920 return err; 4921 4922 return selinux_netlbl_socket_connect(sk, address); 4923 } 4924 4925 static int selinux_socket_listen(struct socket *sock, int backlog) 4926 { 4927 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4928 } 4929 4930 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4931 { 4932 int err; 4933 struct inode_security_struct *isec; 4934 struct inode_security_struct *newisec; 4935 u16 sclass; 4936 u32 sid; 4937 4938 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4939 if (err) 4940 return err; 4941 4942 isec = inode_security_novalidate(SOCK_INODE(sock)); 4943 spin_lock(&isec->lock); 4944 sclass = isec->sclass; 4945 sid = isec->sid; 4946 spin_unlock(&isec->lock); 4947 4948 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4949 newisec->sclass = sclass; 4950 newisec->sid = sid; 4951 newisec->initialized = LABEL_INITIALIZED; 4952 4953 return 0; 4954 } 4955 4956 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4957 int size) 4958 { 4959 return sock_has_perm(sock->sk, SOCKET__WRITE); 4960 } 4961 4962 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4963 int size, int flags) 4964 { 4965 return sock_has_perm(sock->sk, SOCKET__READ); 4966 } 4967 4968 static int selinux_socket_getsockname(struct socket *sock) 4969 { 4970 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4971 } 4972 4973 static int selinux_socket_getpeername(struct socket *sock) 4974 { 4975 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4976 } 4977 4978 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4979 { 4980 int err; 4981 4982 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4983 if (err) 4984 return err; 4985 4986 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4987 } 4988 4989 static int selinux_socket_getsockopt(struct socket *sock, int level, 4990 int optname) 4991 { 4992 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4993 } 4994 4995 static int selinux_socket_shutdown(struct socket *sock, int how) 4996 { 4997 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4998 } 4999 5000 static int selinux_socket_unix_stream_connect(struct sock *sock, 5001 struct sock *other, 5002 struct sock *newsk) 5003 { 5004 struct sk_security_struct *sksec_sock = sock->sk_security; 5005 struct sk_security_struct *sksec_other = other->sk_security; 5006 struct sk_security_struct *sksec_new = newsk->sk_security; 5007 struct common_audit_data ad; 5008 struct lsm_network_audit net; 5009 int err; 5010 5011 ad_net_init_from_sk(&ad, &net, other); 5012 5013 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 5014 sksec_other->sclass, 5015 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 5016 if (err) 5017 return err; 5018 5019 /* server child socket */ 5020 sksec_new->peer_sid = sksec_sock->sid; 5021 err = security_sid_mls_copy(sksec_other->sid, 5022 sksec_sock->sid, &sksec_new->sid); 5023 if (err) 5024 return err; 5025 5026 /* connecting socket */ 5027 sksec_sock->peer_sid = sksec_new->sid; 5028 5029 return 0; 5030 } 5031 5032 static int selinux_socket_unix_may_send(struct socket *sock, 5033 struct socket *other) 5034 { 5035 struct sk_security_struct *ssec = sock->sk->sk_security; 5036 struct sk_security_struct *osec = other->sk->sk_security; 5037 struct common_audit_data ad; 5038 struct lsm_network_audit net; 5039 5040 ad_net_init_from_sk(&ad, &net, other->sk); 5041 5042 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 5043 &ad); 5044 } 5045 5046 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 5047 char *addrp, u16 family, u32 peer_sid, 5048 struct common_audit_data *ad) 5049 { 5050 int err; 5051 u32 if_sid; 5052 u32 node_sid; 5053 5054 err = sel_netif_sid(ns, ifindex, &if_sid); 5055 if (err) 5056 return err; 5057 err = avc_has_perm(peer_sid, if_sid, 5058 SECCLASS_NETIF, NETIF__INGRESS, ad); 5059 if (err) 5060 return err; 5061 5062 err = sel_netnode_sid(addrp, family, &node_sid); 5063 if (err) 5064 return err; 5065 return avc_has_perm(peer_sid, node_sid, 5066 SECCLASS_NODE, NODE__RECVFROM, ad); 5067 } 5068 5069 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 5070 u16 family) 5071 { 5072 int err = 0; 5073 struct sk_security_struct *sksec = sk->sk_security; 5074 u32 sk_sid = sksec->sid; 5075 struct common_audit_data ad; 5076 struct lsm_network_audit net; 5077 char *addrp; 5078 5079 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5080 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5081 if (err) 5082 return err; 5083 5084 if (selinux_secmark_enabled()) { 5085 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5086 PACKET__RECV, &ad); 5087 if (err) 5088 return err; 5089 } 5090 5091 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 5092 if (err) 5093 return err; 5094 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 5095 5096 return err; 5097 } 5098 5099 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 5100 { 5101 int err, peerlbl_active, secmark_active; 5102 struct sk_security_struct *sksec = sk->sk_security; 5103 u16 family = sk->sk_family; 5104 u32 sk_sid = sksec->sid; 5105 struct common_audit_data ad; 5106 struct lsm_network_audit net; 5107 char *addrp; 5108 5109 if (family != PF_INET && family != PF_INET6) 5110 return 0; 5111 5112 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 5113 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5114 family = PF_INET; 5115 5116 /* If any sort of compatibility mode is enabled then handoff processing 5117 * to the selinux_sock_rcv_skb_compat() function to deal with the 5118 * special handling. We do this in an attempt to keep this function 5119 * as fast and as clean as possible. */ 5120 if (!selinux_policycap_netpeer()) 5121 return selinux_sock_rcv_skb_compat(sk, skb, family); 5122 5123 secmark_active = selinux_secmark_enabled(); 5124 peerlbl_active = selinux_peerlbl_enabled(); 5125 if (!secmark_active && !peerlbl_active) 5126 return 0; 5127 5128 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family); 5129 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5130 if (err) 5131 return err; 5132 5133 if (peerlbl_active) { 5134 u32 peer_sid; 5135 5136 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5137 if (err) 5138 return err; 5139 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5140 addrp, family, peer_sid, &ad); 5141 if (err) { 5142 selinux_netlbl_err(skb, family, err, 0); 5143 return err; 5144 } 5145 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 5146 PEER__RECV, &ad); 5147 if (err) { 5148 selinux_netlbl_err(skb, family, err, 0); 5149 return err; 5150 } 5151 } 5152 5153 if (secmark_active) { 5154 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 5155 PACKET__RECV, &ad); 5156 if (err) 5157 return err; 5158 } 5159 5160 return err; 5161 } 5162 5163 static int selinux_socket_getpeersec_stream(struct socket *sock, 5164 sockptr_t optval, sockptr_t optlen, 5165 unsigned int len) 5166 { 5167 int err = 0; 5168 char *scontext = NULL; 5169 u32 scontext_len; 5170 struct sk_security_struct *sksec = sock->sk->sk_security; 5171 u32 peer_sid = SECSID_NULL; 5172 5173 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5174 sksec->sclass == SECCLASS_TCP_SOCKET || 5175 sksec->sclass == SECCLASS_SCTP_SOCKET) 5176 peer_sid = sksec->peer_sid; 5177 if (peer_sid == SECSID_NULL) 5178 return -ENOPROTOOPT; 5179 5180 err = security_sid_to_context(peer_sid, &scontext, 5181 &scontext_len); 5182 if (err) 5183 return err; 5184 if (scontext_len > len) { 5185 err = -ERANGE; 5186 goto out_len; 5187 } 5188 5189 if (copy_to_sockptr(optval, scontext, scontext_len)) 5190 err = -EFAULT; 5191 out_len: 5192 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len))) 5193 err = -EFAULT; 5194 kfree(scontext); 5195 return err; 5196 } 5197 5198 static int selinux_socket_getpeersec_dgram(struct socket *sock, 5199 struct sk_buff *skb, u32 *secid) 5200 { 5201 u32 peer_secid = SECSID_NULL; 5202 u16 family; 5203 5204 if (skb && skb->protocol == htons(ETH_P_IP)) 5205 family = PF_INET; 5206 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5207 family = PF_INET6; 5208 else if (sock) 5209 family = sock->sk->sk_family; 5210 else { 5211 *secid = SECSID_NULL; 5212 return -EINVAL; 5213 } 5214 5215 if (sock && family == PF_UNIX) { 5216 struct inode_security_struct *isec; 5217 isec = inode_security_novalidate(SOCK_INODE(sock)); 5218 peer_secid = isec->sid; 5219 } else if (skb) 5220 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5221 5222 *secid = peer_secid; 5223 if (peer_secid == SECSID_NULL) 5224 return -ENOPROTOOPT; 5225 return 0; 5226 } 5227 5228 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5229 { 5230 struct sk_security_struct *sksec; 5231 5232 sksec = kzalloc(sizeof(*sksec), priority); 5233 if (!sksec) 5234 return -ENOMEM; 5235 5236 sksec->peer_sid = SECINITSID_UNLABELED; 5237 sksec->sid = SECINITSID_UNLABELED; 5238 sksec->sclass = SECCLASS_SOCKET; 5239 selinux_netlbl_sk_security_reset(sksec); 5240 sk->sk_security = sksec; 5241 5242 return 0; 5243 } 5244 5245 static void selinux_sk_free_security(struct sock *sk) 5246 { 5247 struct sk_security_struct *sksec = sk->sk_security; 5248 5249 sk->sk_security = NULL; 5250 selinux_netlbl_sk_security_free(sksec); 5251 kfree(sksec); 5252 } 5253 5254 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5255 { 5256 struct sk_security_struct *sksec = sk->sk_security; 5257 struct sk_security_struct *newsksec = newsk->sk_security; 5258 5259 newsksec->sid = sksec->sid; 5260 newsksec->peer_sid = sksec->peer_sid; 5261 newsksec->sclass = sksec->sclass; 5262 5263 selinux_netlbl_sk_security_reset(newsksec); 5264 } 5265 5266 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) 5267 { 5268 if (!sk) 5269 *secid = SECINITSID_ANY_SOCKET; 5270 else { 5271 const struct sk_security_struct *sksec = sk->sk_security; 5272 5273 *secid = sksec->sid; 5274 } 5275 } 5276 5277 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5278 { 5279 struct inode_security_struct *isec = 5280 inode_security_novalidate(SOCK_INODE(parent)); 5281 struct sk_security_struct *sksec = sk->sk_security; 5282 5283 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5284 sk->sk_family == PF_UNIX) 5285 isec->sid = sksec->sid; 5286 sksec->sclass = isec->sclass; 5287 } 5288 5289 /* 5290 * Determines peer_secid for the asoc and updates socket's peer label 5291 * if it's the first association on the socket. 5292 */ 5293 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, 5294 struct sk_buff *skb) 5295 { 5296 struct sock *sk = asoc->base.sk; 5297 u16 family = sk->sk_family; 5298 struct sk_security_struct *sksec = sk->sk_security; 5299 struct common_audit_data ad; 5300 struct lsm_network_audit net; 5301 int err; 5302 5303 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5304 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5305 family = PF_INET; 5306 5307 if (selinux_peerlbl_enabled()) { 5308 asoc->peer_secid = SECSID_NULL; 5309 5310 /* This will return peer_sid = SECSID_NULL if there are 5311 * no peer labels, see security_net_peersid_resolve(). 5312 */ 5313 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid); 5314 if (err) 5315 return err; 5316 5317 if (asoc->peer_secid == SECSID_NULL) 5318 asoc->peer_secid = SECINITSID_UNLABELED; 5319 } else { 5320 asoc->peer_secid = SECINITSID_UNLABELED; 5321 } 5322 5323 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5324 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5325 5326 /* Here as first association on socket. As the peer SID 5327 * was allowed by peer recv (and the netif/node checks), 5328 * then it is approved by policy and used as the primary 5329 * peer SID for getpeercon(3). 5330 */ 5331 sksec->peer_sid = asoc->peer_secid; 5332 } else if (sksec->peer_sid != asoc->peer_secid) { 5333 /* Other association peer SIDs are checked to enforce 5334 * consistency among the peer SIDs. 5335 */ 5336 ad_net_init_from_sk(&ad, &net, asoc->base.sk); 5337 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, 5338 sksec->sclass, SCTP_SOCKET__ASSOCIATION, 5339 &ad); 5340 if (err) 5341 return err; 5342 } 5343 return 0; 5344 } 5345 5346 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This 5347 * happens on an incoming connect(2), sctp_connectx(3) or 5348 * sctp_sendmsg(3) (with no association already present). 5349 */ 5350 static int selinux_sctp_assoc_request(struct sctp_association *asoc, 5351 struct sk_buff *skb) 5352 { 5353 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5354 u32 conn_sid; 5355 int err; 5356 5357 if (!selinux_policycap_extsockclass()) 5358 return 0; 5359 5360 err = selinux_sctp_process_new_assoc(asoc, skb); 5361 if (err) 5362 return err; 5363 5364 /* Compute the MLS component for the connection and store 5365 * the information in asoc. This will be used by SCTP TCP type 5366 * sockets and peeled off connections as they cause a new 5367 * socket to be generated. selinux_sctp_sk_clone() will then 5368 * plug this into the new socket. 5369 */ 5370 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid); 5371 if (err) 5372 return err; 5373 5374 asoc->secid = conn_sid; 5375 5376 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5377 return selinux_netlbl_sctp_assoc_request(asoc, skb); 5378 } 5379 5380 /* Called when SCTP receives a COOKIE ACK chunk as the final 5381 * response to an association request (initited by us). 5382 */ 5383 static int selinux_sctp_assoc_established(struct sctp_association *asoc, 5384 struct sk_buff *skb) 5385 { 5386 struct sk_security_struct *sksec = asoc->base.sk->sk_security; 5387 5388 if (!selinux_policycap_extsockclass()) 5389 return 0; 5390 5391 /* Inherit secid from the parent socket - this will be picked up 5392 * by selinux_sctp_sk_clone() if the association gets peeled off 5393 * into a new socket. 5394 */ 5395 asoc->secid = sksec->sid; 5396 5397 return selinux_sctp_process_new_assoc(asoc, skb); 5398 } 5399 5400 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5401 * based on their @optname. 5402 */ 5403 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5404 struct sockaddr *address, 5405 int addrlen) 5406 { 5407 int len, err = 0, walk_size = 0; 5408 void *addr_buf; 5409 struct sockaddr *addr; 5410 struct socket *sock; 5411 5412 if (!selinux_policycap_extsockclass()) 5413 return 0; 5414 5415 /* Process one or more addresses that may be IPv4 or IPv6 */ 5416 sock = sk->sk_socket; 5417 addr_buf = address; 5418 5419 while (walk_size < addrlen) { 5420 if (walk_size + sizeof(sa_family_t) > addrlen) 5421 return -EINVAL; 5422 5423 addr = addr_buf; 5424 switch (addr->sa_family) { 5425 case AF_UNSPEC: 5426 case AF_INET: 5427 len = sizeof(struct sockaddr_in); 5428 break; 5429 case AF_INET6: 5430 len = sizeof(struct sockaddr_in6); 5431 break; 5432 default: 5433 return -EINVAL; 5434 } 5435 5436 if (walk_size + len > addrlen) 5437 return -EINVAL; 5438 5439 err = -EINVAL; 5440 switch (optname) { 5441 /* Bind checks */ 5442 case SCTP_PRIMARY_ADDR: 5443 case SCTP_SET_PEER_PRIMARY_ADDR: 5444 case SCTP_SOCKOPT_BINDX_ADD: 5445 err = selinux_socket_bind(sock, addr, len); 5446 break; 5447 /* Connect checks */ 5448 case SCTP_SOCKOPT_CONNECTX: 5449 case SCTP_PARAM_SET_PRIMARY: 5450 case SCTP_PARAM_ADD_IP: 5451 case SCTP_SENDMSG_CONNECT: 5452 err = selinux_socket_connect_helper(sock, addr, len); 5453 if (err) 5454 return err; 5455 5456 /* As selinux_sctp_bind_connect() is called by the 5457 * SCTP protocol layer, the socket is already locked, 5458 * therefore selinux_netlbl_socket_connect_locked() 5459 * is called here. The situations handled are: 5460 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5461 * whenever a new IP address is added or when a new 5462 * primary address is selected. 5463 * Note that an SCTP connect(2) call happens before 5464 * the SCTP protocol layer and is handled via 5465 * selinux_socket_connect(). 5466 */ 5467 err = selinux_netlbl_socket_connect_locked(sk, addr); 5468 break; 5469 } 5470 5471 if (err) 5472 return err; 5473 5474 addr_buf += len; 5475 walk_size += len; 5476 } 5477 5478 return 0; 5479 } 5480 5481 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5482 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5483 struct sock *newsk) 5484 { 5485 struct sk_security_struct *sksec = sk->sk_security; 5486 struct sk_security_struct *newsksec = newsk->sk_security; 5487 5488 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5489 * the non-sctp clone version. 5490 */ 5491 if (!selinux_policycap_extsockclass()) 5492 return selinux_sk_clone_security(sk, newsk); 5493 5494 newsksec->sid = asoc->secid; 5495 newsksec->peer_sid = asoc->peer_secid; 5496 newsksec->sclass = sksec->sclass; 5497 selinux_netlbl_sctp_sk_clone(sk, newsk); 5498 } 5499 5500 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5501 { 5502 struct sk_security_struct *ssksec = ssk->sk_security; 5503 struct sk_security_struct *sksec = sk->sk_security; 5504 5505 ssksec->sclass = sksec->sclass; 5506 ssksec->sid = sksec->sid; 5507 5508 /* replace the existing subflow label deleting the existing one 5509 * and re-recreating a new label using the updated context 5510 */ 5511 selinux_netlbl_sk_security_free(ssksec); 5512 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); 5513 } 5514 5515 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 5516 struct request_sock *req) 5517 { 5518 struct sk_security_struct *sksec = sk->sk_security; 5519 int err; 5520 u16 family = req->rsk_ops->family; 5521 u32 connsid; 5522 u32 peersid; 5523 5524 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5525 if (err) 5526 return err; 5527 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5528 if (err) 5529 return err; 5530 req->secid = connsid; 5531 req->peer_secid = peersid; 5532 5533 return selinux_netlbl_inet_conn_request(req, family); 5534 } 5535 5536 static void selinux_inet_csk_clone(struct sock *newsk, 5537 const struct request_sock *req) 5538 { 5539 struct sk_security_struct *newsksec = newsk->sk_security; 5540 5541 newsksec->sid = req->secid; 5542 newsksec->peer_sid = req->peer_secid; 5543 /* NOTE: Ideally, we should also get the isec->sid for the 5544 new socket in sync, but we don't have the isec available yet. 5545 So we will wait until sock_graft to do it, by which 5546 time it will have been created and available. */ 5547 5548 /* We don't need to take any sort of lock here as we are the only 5549 * thread with access to newsksec */ 5550 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5551 } 5552 5553 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5554 { 5555 u16 family = sk->sk_family; 5556 struct sk_security_struct *sksec = sk->sk_security; 5557 5558 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5559 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5560 family = PF_INET; 5561 5562 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5563 } 5564 5565 static int selinux_secmark_relabel_packet(u32 sid) 5566 { 5567 const struct task_security_struct *tsec; 5568 u32 tsid; 5569 5570 tsec = selinux_cred(current_cred()); 5571 tsid = tsec->sid; 5572 5573 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5574 NULL); 5575 } 5576 5577 static void selinux_secmark_refcount_inc(void) 5578 { 5579 atomic_inc(&selinux_secmark_refcount); 5580 } 5581 5582 static void selinux_secmark_refcount_dec(void) 5583 { 5584 atomic_dec(&selinux_secmark_refcount); 5585 } 5586 5587 static void selinux_req_classify_flow(const struct request_sock *req, 5588 struct flowi_common *flic) 5589 { 5590 flic->flowic_secid = req->secid; 5591 } 5592 5593 static int selinux_tun_dev_alloc_security(void **security) 5594 { 5595 struct tun_security_struct *tunsec; 5596 5597 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5598 if (!tunsec) 5599 return -ENOMEM; 5600 tunsec->sid = current_sid(); 5601 5602 *security = tunsec; 5603 return 0; 5604 } 5605 5606 static void selinux_tun_dev_free_security(void *security) 5607 { 5608 kfree(security); 5609 } 5610 5611 static int selinux_tun_dev_create(void) 5612 { 5613 u32 sid = current_sid(); 5614 5615 /* we aren't taking into account the "sockcreate" SID since the socket 5616 * that is being created here is not a socket in the traditional sense, 5617 * instead it is a private sock, accessible only to the kernel, and 5618 * representing a wide range of network traffic spanning multiple 5619 * connections unlike traditional sockets - check the TUN driver to 5620 * get a better understanding of why this socket is special */ 5621 5622 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5623 NULL); 5624 } 5625 5626 static int selinux_tun_dev_attach_queue(void *security) 5627 { 5628 struct tun_security_struct *tunsec = security; 5629 5630 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5631 TUN_SOCKET__ATTACH_QUEUE, NULL); 5632 } 5633 5634 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5635 { 5636 struct tun_security_struct *tunsec = security; 5637 struct sk_security_struct *sksec = sk->sk_security; 5638 5639 /* we don't currently perform any NetLabel based labeling here and it 5640 * isn't clear that we would want to do so anyway; while we could apply 5641 * labeling without the support of the TUN user the resulting labeled 5642 * traffic from the other end of the connection would almost certainly 5643 * cause confusion to the TUN user that had no idea network labeling 5644 * protocols were being used */ 5645 5646 sksec->sid = tunsec->sid; 5647 sksec->sclass = SECCLASS_TUN_SOCKET; 5648 5649 return 0; 5650 } 5651 5652 static int selinux_tun_dev_open(void *security) 5653 { 5654 struct tun_security_struct *tunsec = security; 5655 u32 sid = current_sid(); 5656 int err; 5657 5658 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5659 TUN_SOCKET__RELABELFROM, NULL); 5660 if (err) 5661 return err; 5662 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5663 TUN_SOCKET__RELABELTO, NULL); 5664 if (err) 5665 return err; 5666 tunsec->sid = sid; 5667 5668 return 0; 5669 } 5670 5671 #ifdef CONFIG_NETFILTER 5672 5673 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, 5674 const struct nf_hook_state *state) 5675 { 5676 int ifindex; 5677 u16 family; 5678 char *addrp; 5679 u32 peer_sid; 5680 struct common_audit_data ad; 5681 struct lsm_network_audit net; 5682 int secmark_active, peerlbl_active; 5683 5684 if (!selinux_policycap_netpeer()) 5685 return NF_ACCEPT; 5686 5687 secmark_active = selinux_secmark_enabled(); 5688 peerlbl_active = selinux_peerlbl_enabled(); 5689 if (!secmark_active && !peerlbl_active) 5690 return NF_ACCEPT; 5691 5692 family = state->pf; 5693 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5694 return NF_DROP; 5695 5696 ifindex = state->in->ifindex; 5697 ad_net_init_from_iif(&ad, &net, ifindex, family); 5698 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5699 return NF_DROP; 5700 5701 if (peerlbl_active) { 5702 int err; 5703 5704 err = selinux_inet_sys_rcv_skb(state->net, ifindex, 5705 addrp, family, peer_sid, &ad); 5706 if (err) { 5707 selinux_netlbl_err(skb, family, err, 1); 5708 return NF_DROP; 5709 } 5710 } 5711 5712 if (secmark_active) 5713 if (avc_has_perm(peer_sid, skb->secmark, 5714 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5715 return NF_DROP; 5716 5717 if (netlbl_enabled()) 5718 /* we do this in the FORWARD path and not the POST_ROUTING 5719 * path because we want to make sure we apply the necessary 5720 * labeling before IPsec is applied so we can leverage AH 5721 * protection */ 5722 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5723 return NF_DROP; 5724 5725 return NF_ACCEPT; 5726 } 5727 5728 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, 5729 const struct nf_hook_state *state) 5730 { 5731 struct sock *sk; 5732 u32 sid; 5733 5734 if (!netlbl_enabled()) 5735 return NF_ACCEPT; 5736 5737 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5738 * because we want to make sure we apply the necessary labeling 5739 * before IPsec is applied so we can leverage AH protection */ 5740 sk = skb->sk; 5741 if (sk) { 5742 struct sk_security_struct *sksec; 5743 5744 if (sk_listener(sk)) 5745 /* if the socket is the listening state then this 5746 * packet is a SYN-ACK packet which means it needs to 5747 * be labeled based on the connection/request_sock and 5748 * not the parent socket. unfortunately, we can't 5749 * lookup the request_sock yet as it isn't queued on 5750 * the parent socket until after the SYN-ACK is sent. 5751 * the "solution" is to simply pass the packet as-is 5752 * as any IP option based labeling should be copied 5753 * from the initial connection request (in the IP 5754 * layer). it is far from ideal, but until we get a 5755 * security label in the packet itself this is the 5756 * best we can do. */ 5757 return NF_ACCEPT; 5758 5759 /* standard practice, label using the parent socket */ 5760 sksec = sk->sk_security; 5761 sid = sksec->sid; 5762 } else 5763 sid = SECINITSID_KERNEL; 5764 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) 5765 return NF_DROP; 5766 5767 return NF_ACCEPT; 5768 } 5769 5770 5771 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5772 const struct nf_hook_state *state) 5773 { 5774 struct sock *sk; 5775 struct sk_security_struct *sksec; 5776 struct common_audit_data ad; 5777 struct lsm_network_audit net; 5778 u8 proto = 0; 5779 5780 sk = skb_to_full_sk(skb); 5781 if (sk == NULL) 5782 return NF_ACCEPT; 5783 sksec = sk->sk_security; 5784 5785 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf); 5786 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto)) 5787 return NF_DROP; 5788 5789 if (selinux_secmark_enabled()) 5790 if (avc_has_perm(sksec->sid, skb->secmark, 5791 SECCLASS_PACKET, PACKET__SEND, &ad)) 5792 return NF_DROP_ERR(-ECONNREFUSED); 5793 5794 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5795 return NF_DROP_ERR(-ECONNREFUSED); 5796 5797 return NF_ACCEPT; 5798 } 5799 5800 static unsigned int selinux_ip_postroute(void *priv, 5801 struct sk_buff *skb, 5802 const struct nf_hook_state *state) 5803 { 5804 u16 family; 5805 u32 secmark_perm; 5806 u32 peer_sid; 5807 int ifindex; 5808 struct sock *sk; 5809 struct common_audit_data ad; 5810 struct lsm_network_audit net; 5811 char *addrp; 5812 int secmark_active, peerlbl_active; 5813 5814 /* If any sort of compatibility mode is enabled then handoff processing 5815 * to the selinux_ip_postroute_compat() function to deal with the 5816 * special handling. We do this in an attempt to keep this function 5817 * as fast and as clean as possible. */ 5818 if (!selinux_policycap_netpeer()) 5819 return selinux_ip_postroute_compat(skb, state); 5820 5821 secmark_active = selinux_secmark_enabled(); 5822 peerlbl_active = selinux_peerlbl_enabled(); 5823 if (!secmark_active && !peerlbl_active) 5824 return NF_ACCEPT; 5825 5826 sk = skb_to_full_sk(skb); 5827 5828 #ifdef CONFIG_XFRM 5829 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5830 * packet transformation so allow the packet to pass without any checks 5831 * since we'll have another chance to perform access control checks 5832 * when the packet is on it's final way out. 5833 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5834 * is NULL, in this case go ahead and apply access control. 5835 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5836 * TCP listening state we cannot wait until the XFRM processing 5837 * is done as we will miss out on the SA label if we do; 5838 * unfortunately, this means more work, but it is only once per 5839 * connection. */ 5840 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5841 !(sk && sk_listener(sk))) 5842 return NF_ACCEPT; 5843 #endif 5844 5845 family = state->pf; 5846 if (sk == NULL) { 5847 /* Without an associated socket the packet is either coming 5848 * from the kernel or it is being forwarded; check the packet 5849 * to determine which and if the packet is being forwarded 5850 * query the packet directly to determine the security label. */ 5851 if (skb->skb_iif) { 5852 secmark_perm = PACKET__FORWARD_OUT; 5853 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5854 return NF_DROP; 5855 } else { 5856 secmark_perm = PACKET__SEND; 5857 peer_sid = SECINITSID_KERNEL; 5858 } 5859 } else if (sk_listener(sk)) { 5860 /* Locally generated packet but the associated socket is in the 5861 * listening state which means this is a SYN-ACK packet. In 5862 * this particular case the correct security label is assigned 5863 * to the connection/request_sock but unfortunately we can't 5864 * query the request_sock as it isn't queued on the parent 5865 * socket until after the SYN-ACK packet is sent; the only 5866 * viable choice is to regenerate the label like we do in 5867 * selinux_inet_conn_request(). See also selinux_ip_output() 5868 * for similar problems. */ 5869 u32 skb_sid; 5870 struct sk_security_struct *sksec; 5871 5872 sksec = sk->sk_security; 5873 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5874 return NF_DROP; 5875 /* At this point, if the returned skb peerlbl is SECSID_NULL 5876 * and the packet has been through at least one XFRM 5877 * transformation then we must be dealing with the "final" 5878 * form of labeled IPsec packet; since we've already applied 5879 * all of our access controls on this packet we can safely 5880 * pass the packet. */ 5881 if (skb_sid == SECSID_NULL) { 5882 switch (family) { 5883 case PF_INET: 5884 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5885 return NF_ACCEPT; 5886 break; 5887 case PF_INET6: 5888 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5889 return NF_ACCEPT; 5890 break; 5891 default: 5892 return NF_DROP_ERR(-ECONNREFUSED); 5893 } 5894 } 5895 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5896 return NF_DROP; 5897 secmark_perm = PACKET__SEND; 5898 } else { 5899 /* Locally generated packet, fetch the security label from the 5900 * associated socket. */ 5901 struct sk_security_struct *sksec = sk->sk_security; 5902 peer_sid = sksec->sid; 5903 secmark_perm = PACKET__SEND; 5904 } 5905 5906 ifindex = state->out->ifindex; 5907 ad_net_init_from_iif(&ad, &net, ifindex, family); 5908 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5909 return NF_DROP; 5910 5911 if (secmark_active) 5912 if (avc_has_perm(peer_sid, skb->secmark, 5913 SECCLASS_PACKET, secmark_perm, &ad)) 5914 return NF_DROP_ERR(-ECONNREFUSED); 5915 5916 if (peerlbl_active) { 5917 u32 if_sid; 5918 u32 node_sid; 5919 5920 if (sel_netif_sid(state->net, ifindex, &if_sid)) 5921 return NF_DROP; 5922 if (avc_has_perm(peer_sid, if_sid, 5923 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5924 return NF_DROP_ERR(-ECONNREFUSED); 5925 5926 if (sel_netnode_sid(addrp, family, &node_sid)) 5927 return NF_DROP; 5928 if (avc_has_perm(peer_sid, node_sid, 5929 SECCLASS_NODE, NODE__SENDTO, &ad)) 5930 return NF_DROP_ERR(-ECONNREFUSED); 5931 } 5932 5933 return NF_ACCEPT; 5934 } 5935 #endif /* CONFIG_NETFILTER */ 5936 5937 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5938 { 5939 int rc = 0; 5940 unsigned int msg_len; 5941 unsigned int data_len = skb->len; 5942 unsigned char *data = skb->data; 5943 struct nlmsghdr *nlh; 5944 struct sk_security_struct *sksec = sk->sk_security; 5945 u16 sclass = sksec->sclass; 5946 u32 perm; 5947 5948 while (data_len >= nlmsg_total_size(0)) { 5949 nlh = (struct nlmsghdr *)data; 5950 5951 /* NOTE: the nlmsg_len field isn't reliably set by some netlink 5952 * users which means we can't reject skb's with bogus 5953 * length fields; our solution is to follow what 5954 * netlink_rcv_skb() does and simply skip processing at 5955 * messages with length fields that are clearly junk 5956 */ 5957 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) 5958 return 0; 5959 5960 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); 5961 if (rc == 0) { 5962 rc = sock_has_perm(sk, perm); 5963 if (rc) 5964 return rc; 5965 } else if (rc == -EINVAL) { 5966 /* -EINVAL is a missing msg/perm mapping */ 5967 pr_warn_ratelimited("SELinux: unrecognized netlink" 5968 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5969 " pid=%d comm=%s\n", 5970 sk->sk_protocol, nlh->nlmsg_type, 5971 secclass_map[sclass - 1].name, 5972 task_pid_nr(current), current->comm); 5973 if (enforcing_enabled() && 5974 !security_get_allow_unknown()) 5975 return rc; 5976 rc = 0; 5977 } else if (rc == -ENOENT) { 5978 /* -ENOENT is a missing socket/class mapping, ignore */ 5979 rc = 0; 5980 } else { 5981 return rc; 5982 } 5983 5984 /* move to the next message after applying netlink padding */ 5985 msg_len = NLMSG_ALIGN(nlh->nlmsg_len); 5986 if (msg_len >= data_len) 5987 return 0; 5988 data_len -= msg_len; 5989 data += msg_len; 5990 } 5991 5992 return rc; 5993 } 5994 5995 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) 5996 { 5997 isec->sclass = sclass; 5998 isec->sid = current_sid(); 5999 } 6000 6001 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 6002 u32 perms) 6003 { 6004 struct ipc_security_struct *isec; 6005 struct common_audit_data ad; 6006 u32 sid = current_sid(); 6007 6008 isec = selinux_ipc(ipc_perms); 6009 6010 ad.type = LSM_AUDIT_DATA_IPC; 6011 ad.u.ipc_id = ipc_perms->key; 6012 6013 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 6014 } 6015 6016 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 6017 { 6018 struct msg_security_struct *msec; 6019 6020 msec = selinux_msg_msg(msg); 6021 msec->sid = SECINITSID_UNLABELED; 6022 6023 return 0; 6024 } 6025 6026 /* message queue security operations */ 6027 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) 6028 { 6029 struct ipc_security_struct *isec; 6030 struct common_audit_data ad; 6031 u32 sid = current_sid(); 6032 6033 isec = selinux_ipc(msq); 6034 ipc_init_security(isec, SECCLASS_MSGQ); 6035 6036 ad.type = LSM_AUDIT_DATA_IPC; 6037 ad.u.ipc_id = msq->key; 6038 6039 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6040 MSGQ__CREATE, &ad); 6041 } 6042 6043 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 6044 { 6045 struct ipc_security_struct *isec; 6046 struct common_audit_data ad; 6047 u32 sid = current_sid(); 6048 6049 isec = selinux_ipc(msq); 6050 6051 ad.type = LSM_AUDIT_DATA_IPC; 6052 ad.u.ipc_id = msq->key; 6053 6054 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6055 MSGQ__ASSOCIATE, &ad); 6056 } 6057 6058 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 6059 { 6060 u32 perms; 6061 6062 switch (cmd) { 6063 case IPC_INFO: 6064 case MSG_INFO: 6065 /* No specific object, just general system-wide information. */ 6066 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6067 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6068 case IPC_STAT: 6069 case MSG_STAT: 6070 case MSG_STAT_ANY: 6071 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6072 break; 6073 case IPC_SET: 6074 perms = MSGQ__SETATTR; 6075 break; 6076 case IPC_RMID: 6077 perms = MSGQ__DESTROY; 6078 break; 6079 default: 6080 return 0; 6081 } 6082 6083 return ipc_has_perm(msq, perms); 6084 } 6085 6086 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) 6087 { 6088 struct ipc_security_struct *isec; 6089 struct msg_security_struct *msec; 6090 struct common_audit_data ad; 6091 u32 sid = current_sid(); 6092 int rc; 6093 6094 isec = selinux_ipc(msq); 6095 msec = selinux_msg_msg(msg); 6096 6097 /* 6098 * First time through, need to assign label to the message 6099 */ 6100 if (msec->sid == SECINITSID_UNLABELED) { 6101 /* 6102 * Compute new sid based on current process and 6103 * message queue this message will be stored in 6104 */ 6105 rc = security_transition_sid(sid, isec->sid, 6106 SECCLASS_MSG, NULL, &msec->sid); 6107 if (rc) 6108 return rc; 6109 } 6110 6111 ad.type = LSM_AUDIT_DATA_IPC; 6112 ad.u.ipc_id = msq->key; 6113 6114 /* Can this process write to the queue? */ 6115 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 6116 MSGQ__WRITE, &ad); 6117 if (!rc) 6118 /* Can this process send the message */ 6119 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 6120 MSG__SEND, &ad); 6121 if (!rc) 6122 /* Can the message be put in the queue? */ 6123 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 6124 MSGQ__ENQUEUE, &ad); 6125 6126 return rc; 6127 } 6128 6129 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 6130 struct task_struct *target, 6131 long type, int mode) 6132 { 6133 struct ipc_security_struct *isec; 6134 struct msg_security_struct *msec; 6135 struct common_audit_data ad; 6136 u32 sid = task_sid_obj(target); 6137 int rc; 6138 6139 isec = selinux_ipc(msq); 6140 msec = selinux_msg_msg(msg); 6141 6142 ad.type = LSM_AUDIT_DATA_IPC; 6143 ad.u.ipc_id = msq->key; 6144 6145 rc = avc_has_perm(sid, isec->sid, 6146 SECCLASS_MSGQ, MSGQ__READ, &ad); 6147 if (!rc) 6148 rc = avc_has_perm(sid, msec->sid, 6149 SECCLASS_MSG, MSG__RECEIVE, &ad); 6150 return rc; 6151 } 6152 6153 /* Shared Memory security operations */ 6154 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) 6155 { 6156 struct ipc_security_struct *isec; 6157 struct common_audit_data ad; 6158 u32 sid = current_sid(); 6159 6160 isec = selinux_ipc(shp); 6161 ipc_init_security(isec, SECCLASS_SHM); 6162 6163 ad.type = LSM_AUDIT_DATA_IPC; 6164 ad.u.ipc_id = shp->key; 6165 6166 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6167 SHM__CREATE, &ad); 6168 } 6169 6170 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) 6171 { 6172 struct ipc_security_struct *isec; 6173 struct common_audit_data ad; 6174 u32 sid = current_sid(); 6175 6176 isec = selinux_ipc(shp); 6177 6178 ad.type = LSM_AUDIT_DATA_IPC; 6179 ad.u.ipc_id = shp->key; 6180 6181 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 6182 SHM__ASSOCIATE, &ad); 6183 } 6184 6185 /* Note, at this point, shp is locked down */ 6186 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 6187 { 6188 u32 perms; 6189 6190 switch (cmd) { 6191 case IPC_INFO: 6192 case SHM_INFO: 6193 /* No specific object, just general system-wide information. */ 6194 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6195 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6196 case IPC_STAT: 6197 case SHM_STAT: 6198 case SHM_STAT_ANY: 6199 perms = SHM__GETATTR | SHM__ASSOCIATE; 6200 break; 6201 case IPC_SET: 6202 perms = SHM__SETATTR; 6203 break; 6204 case SHM_LOCK: 6205 case SHM_UNLOCK: 6206 perms = SHM__LOCK; 6207 break; 6208 case IPC_RMID: 6209 perms = SHM__DESTROY; 6210 break; 6211 default: 6212 return 0; 6213 } 6214 6215 return ipc_has_perm(shp, perms); 6216 } 6217 6218 static int selinux_shm_shmat(struct kern_ipc_perm *shp, 6219 char __user *shmaddr, int shmflg) 6220 { 6221 u32 perms; 6222 6223 if (shmflg & SHM_RDONLY) 6224 perms = SHM__READ; 6225 else 6226 perms = SHM__READ | SHM__WRITE; 6227 6228 return ipc_has_perm(shp, perms); 6229 } 6230 6231 /* Semaphore security operations */ 6232 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) 6233 { 6234 struct ipc_security_struct *isec; 6235 struct common_audit_data ad; 6236 u32 sid = current_sid(); 6237 6238 isec = selinux_ipc(sma); 6239 ipc_init_security(isec, SECCLASS_SEM); 6240 6241 ad.type = LSM_AUDIT_DATA_IPC; 6242 ad.u.ipc_id = sma->key; 6243 6244 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6245 SEM__CREATE, &ad); 6246 } 6247 6248 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) 6249 { 6250 struct ipc_security_struct *isec; 6251 struct common_audit_data ad; 6252 u32 sid = current_sid(); 6253 6254 isec = selinux_ipc(sma); 6255 6256 ad.type = LSM_AUDIT_DATA_IPC; 6257 ad.u.ipc_id = sma->key; 6258 6259 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 6260 SEM__ASSOCIATE, &ad); 6261 } 6262 6263 /* Note, at this point, sma is locked down */ 6264 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) 6265 { 6266 int err; 6267 u32 perms; 6268 6269 switch (cmd) { 6270 case IPC_INFO: 6271 case SEM_INFO: 6272 /* No specific object, just general system-wide information. */ 6273 return avc_has_perm(current_sid(), SECINITSID_KERNEL, 6274 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6275 case GETPID: 6276 case GETNCNT: 6277 case GETZCNT: 6278 perms = SEM__GETATTR; 6279 break; 6280 case GETVAL: 6281 case GETALL: 6282 perms = SEM__READ; 6283 break; 6284 case SETVAL: 6285 case SETALL: 6286 perms = SEM__WRITE; 6287 break; 6288 case IPC_RMID: 6289 perms = SEM__DESTROY; 6290 break; 6291 case IPC_SET: 6292 perms = SEM__SETATTR; 6293 break; 6294 case IPC_STAT: 6295 case SEM_STAT: 6296 case SEM_STAT_ANY: 6297 perms = SEM__GETATTR | SEM__ASSOCIATE; 6298 break; 6299 default: 6300 return 0; 6301 } 6302 6303 err = ipc_has_perm(sma, perms); 6304 return err; 6305 } 6306 6307 static int selinux_sem_semop(struct kern_ipc_perm *sma, 6308 struct sembuf *sops, unsigned nsops, int alter) 6309 { 6310 u32 perms; 6311 6312 if (alter) 6313 perms = SEM__READ | SEM__WRITE; 6314 else 6315 perms = SEM__READ; 6316 6317 return ipc_has_perm(sma, perms); 6318 } 6319 6320 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6321 { 6322 u32 av = 0; 6323 6324 av = 0; 6325 if (flag & S_IRUGO) 6326 av |= IPC__UNIX_READ; 6327 if (flag & S_IWUGO) 6328 av |= IPC__UNIX_WRITE; 6329 6330 if (av == 0) 6331 return 0; 6332 6333 return ipc_has_perm(ipcp, av); 6334 } 6335 6336 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6337 { 6338 struct ipc_security_struct *isec = selinux_ipc(ipcp); 6339 *secid = isec->sid; 6340 } 6341 6342 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6343 { 6344 if (inode) 6345 inode_doinit_with_dentry(inode, dentry); 6346 } 6347 6348 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p, 6349 char **value) 6350 { 6351 const struct task_security_struct *__tsec; 6352 u32 sid; 6353 int error; 6354 unsigned len; 6355 6356 rcu_read_lock(); 6357 __tsec = selinux_cred(__task_cred(p)); 6358 6359 if (current != p) { 6360 error = avc_has_perm(current_sid(), __tsec->sid, 6361 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6362 if (error) 6363 goto bad; 6364 } 6365 6366 switch (attr) { 6367 case LSM_ATTR_CURRENT: 6368 sid = __tsec->sid; 6369 break; 6370 case LSM_ATTR_PREV: 6371 sid = __tsec->osid; 6372 break; 6373 case LSM_ATTR_EXEC: 6374 sid = __tsec->exec_sid; 6375 break; 6376 case LSM_ATTR_FSCREATE: 6377 sid = __tsec->create_sid; 6378 break; 6379 case LSM_ATTR_KEYCREATE: 6380 sid = __tsec->keycreate_sid; 6381 break; 6382 case LSM_ATTR_SOCKCREATE: 6383 sid = __tsec->sockcreate_sid; 6384 break; 6385 default: 6386 error = -EOPNOTSUPP; 6387 goto bad; 6388 } 6389 rcu_read_unlock(); 6390 6391 if (!sid) 6392 return 0; 6393 6394 error = security_sid_to_context(sid, value, &len); 6395 if (error) 6396 return error; 6397 return len; 6398 6399 bad: 6400 rcu_read_unlock(); 6401 return error; 6402 } 6403 6404 static int selinux_lsm_setattr(u64 attr, void *value, size_t size) 6405 { 6406 struct task_security_struct *tsec; 6407 struct cred *new; 6408 u32 mysid = current_sid(), sid = 0, ptsid; 6409 int error; 6410 char *str = value; 6411 6412 /* 6413 * Basic control over ability to set these attributes at all. 6414 */ 6415 switch (attr) { 6416 case LSM_ATTR_EXEC: 6417 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6418 PROCESS__SETEXEC, NULL); 6419 break; 6420 case LSM_ATTR_FSCREATE: 6421 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6422 PROCESS__SETFSCREATE, NULL); 6423 break; 6424 case LSM_ATTR_KEYCREATE: 6425 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6426 PROCESS__SETKEYCREATE, NULL); 6427 break; 6428 case LSM_ATTR_SOCKCREATE: 6429 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6430 PROCESS__SETSOCKCREATE, NULL); 6431 break; 6432 case LSM_ATTR_CURRENT: 6433 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, 6434 PROCESS__SETCURRENT, NULL); 6435 break; 6436 default: 6437 error = -EOPNOTSUPP; 6438 break; 6439 } 6440 if (error) 6441 return error; 6442 6443 /* Obtain a SID for the context, if one was specified. */ 6444 if (size && str[0] && str[0] != '\n') { 6445 if (str[size-1] == '\n') { 6446 str[size-1] = 0; 6447 size--; 6448 } 6449 error = security_context_to_sid(value, size, 6450 &sid, GFP_KERNEL); 6451 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) { 6452 if (!has_cap_mac_admin(true)) { 6453 struct audit_buffer *ab; 6454 size_t audit_size; 6455 6456 /* We strip a nul only if it is at the end, 6457 * otherwise the context contains a nul and 6458 * we should audit that */ 6459 if (str[size - 1] == '\0') 6460 audit_size = size - 1; 6461 else 6462 audit_size = size; 6463 ab = audit_log_start(audit_context(), 6464 GFP_ATOMIC, 6465 AUDIT_SELINUX_ERR); 6466 if (!ab) 6467 return error; 6468 audit_log_format(ab, "op=fscreate invalid_context="); 6469 audit_log_n_untrustedstring(ab, value, 6470 audit_size); 6471 audit_log_end(ab); 6472 6473 return error; 6474 } 6475 error = security_context_to_sid_force(value, size, 6476 &sid); 6477 } 6478 if (error) 6479 return error; 6480 } 6481 6482 new = prepare_creds(); 6483 if (!new) 6484 return -ENOMEM; 6485 6486 /* Permission checking based on the specified context is 6487 performed during the actual operation (execve, 6488 open/mkdir/...), when we know the full context of the 6489 operation. See selinux_bprm_creds_for_exec for the execve 6490 checks and may_create for the file creation checks. The 6491 operation will then fail if the context is not permitted. */ 6492 tsec = selinux_cred(new); 6493 if (attr == LSM_ATTR_EXEC) { 6494 tsec->exec_sid = sid; 6495 } else if (attr == LSM_ATTR_FSCREATE) { 6496 tsec->create_sid = sid; 6497 } else if (attr == LSM_ATTR_KEYCREATE) { 6498 if (sid) { 6499 error = avc_has_perm(mysid, sid, 6500 SECCLASS_KEY, KEY__CREATE, NULL); 6501 if (error) 6502 goto abort_change; 6503 } 6504 tsec->keycreate_sid = sid; 6505 } else if (attr == LSM_ATTR_SOCKCREATE) { 6506 tsec->sockcreate_sid = sid; 6507 } else if (attr == LSM_ATTR_CURRENT) { 6508 error = -EINVAL; 6509 if (sid == 0) 6510 goto abort_change; 6511 6512 if (!current_is_single_threaded()) { 6513 error = security_bounded_transition(tsec->sid, sid); 6514 if (error) 6515 goto abort_change; 6516 } 6517 6518 /* Check permissions for the transition. */ 6519 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6520 PROCESS__DYNTRANSITION, NULL); 6521 if (error) 6522 goto abort_change; 6523 6524 /* Check for ptracing, and update the task SID if ok. 6525 Otherwise, leave SID unchanged and fail. */ 6526 ptsid = ptrace_parent_sid(); 6527 if (ptsid != 0) { 6528 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6529 PROCESS__PTRACE, NULL); 6530 if (error) 6531 goto abort_change; 6532 } 6533 6534 tsec->sid = sid; 6535 } else { 6536 error = -EINVAL; 6537 goto abort_change; 6538 } 6539 6540 commit_creds(new); 6541 return size; 6542 6543 abort_change: 6544 abort_creds(new); 6545 return error; 6546 } 6547 6548 /** 6549 * selinux_getselfattr - Get SELinux current task attributes 6550 * @attr: the requested attribute 6551 * @ctx: buffer to receive the result 6552 * @size: buffer size (input), buffer size used (output) 6553 * @flags: unused 6554 * 6555 * Fill the passed user space @ctx with the details of the requested 6556 * attribute. 6557 * 6558 * Returns the number of attributes on success, an error code otherwise. 6559 * There will only ever be one attribute. 6560 */ 6561 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, 6562 u32 *size, u32 flags) 6563 { 6564 int rc; 6565 char *val = NULL; 6566 int val_len; 6567 6568 val_len = selinux_lsm_getattr(attr, current, &val); 6569 if (val_len < 0) 6570 return val_len; 6571 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0); 6572 kfree(val); 6573 return (!rc ? 1 : rc); 6574 } 6575 6576 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx, 6577 u32 size, u32 flags) 6578 { 6579 int rc; 6580 6581 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len); 6582 if (rc > 0) 6583 return 0; 6584 return rc; 6585 } 6586 6587 static int selinux_getprocattr(struct task_struct *p, 6588 const char *name, char **value) 6589 { 6590 unsigned int attr = lsm_name_to_attr(name); 6591 int rc; 6592 6593 if (attr) { 6594 rc = selinux_lsm_getattr(attr, p, value); 6595 if (rc != -EOPNOTSUPP) 6596 return rc; 6597 } 6598 6599 return -EINVAL; 6600 } 6601 6602 static int selinux_setprocattr(const char *name, void *value, size_t size) 6603 { 6604 int attr = lsm_name_to_attr(name); 6605 6606 if (attr) 6607 return selinux_lsm_setattr(attr, value, size); 6608 return -EINVAL; 6609 } 6610 6611 static int selinux_ismaclabel(const char *name) 6612 { 6613 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6614 } 6615 6616 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6617 { 6618 return security_sid_to_context(secid, 6619 secdata, seclen); 6620 } 6621 6622 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6623 { 6624 return security_context_to_sid(secdata, seclen, 6625 secid, GFP_KERNEL); 6626 } 6627 6628 static void selinux_release_secctx(char *secdata, u32 seclen) 6629 { 6630 kfree(secdata); 6631 } 6632 6633 static void selinux_inode_invalidate_secctx(struct inode *inode) 6634 { 6635 struct inode_security_struct *isec = selinux_inode(inode); 6636 6637 spin_lock(&isec->lock); 6638 isec->initialized = LABEL_INVALID; 6639 spin_unlock(&isec->lock); 6640 } 6641 6642 /* 6643 * called with inode->i_mutex locked 6644 */ 6645 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6646 { 6647 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, 6648 ctx, ctxlen, 0); 6649 /* Do not return error when suppressing label (SBLABEL_MNT not set). */ 6650 return rc == -EOPNOTSUPP ? 0 : rc; 6651 } 6652 6653 /* 6654 * called with inode->i_mutex locked 6655 */ 6656 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6657 { 6658 return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, 6659 ctx, ctxlen, 0); 6660 } 6661 6662 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6663 { 6664 int len = 0; 6665 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode, 6666 XATTR_SELINUX_SUFFIX, ctx, true); 6667 if (len < 0) 6668 return len; 6669 *ctxlen = len; 6670 return 0; 6671 } 6672 #ifdef CONFIG_KEYS 6673 6674 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6675 unsigned long flags) 6676 { 6677 const struct task_security_struct *tsec; 6678 struct key_security_struct *ksec; 6679 6680 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6681 if (!ksec) 6682 return -ENOMEM; 6683 6684 tsec = selinux_cred(cred); 6685 if (tsec->keycreate_sid) 6686 ksec->sid = tsec->keycreate_sid; 6687 else 6688 ksec->sid = tsec->sid; 6689 6690 k->security = ksec; 6691 return 0; 6692 } 6693 6694 static void selinux_key_free(struct key *k) 6695 { 6696 struct key_security_struct *ksec = k->security; 6697 6698 k->security = NULL; 6699 kfree(ksec); 6700 } 6701 6702 static int selinux_key_permission(key_ref_t key_ref, 6703 const struct cred *cred, 6704 enum key_need_perm need_perm) 6705 { 6706 struct key *key; 6707 struct key_security_struct *ksec; 6708 u32 perm, sid; 6709 6710 switch (need_perm) { 6711 case KEY_NEED_VIEW: 6712 perm = KEY__VIEW; 6713 break; 6714 case KEY_NEED_READ: 6715 perm = KEY__READ; 6716 break; 6717 case KEY_NEED_WRITE: 6718 perm = KEY__WRITE; 6719 break; 6720 case KEY_NEED_SEARCH: 6721 perm = KEY__SEARCH; 6722 break; 6723 case KEY_NEED_LINK: 6724 perm = KEY__LINK; 6725 break; 6726 case KEY_NEED_SETATTR: 6727 perm = KEY__SETATTR; 6728 break; 6729 case KEY_NEED_UNLINK: 6730 case KEY_SYSADMIN_OVERRIDE: 6731 case KEY_AUTHTOKEN_OVERRIDE: 6732 case KEY_DEFER_PERM_CHECK: 6733 return 0; 6734 default: 6735 WARN_ON(1); 6736 return -EPERM; 6737 6738 } 6739 6740 sid = cred_sid(cred); 6741 key = key_ref_to_ptr(key_ref); 6742 ksec = key->security; 6743 6744 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6745 } 6746 6747 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6748 { 6749 struct key_security_struct *ksec = key->security; 6750 char *context = NULL; 6751 unsigned len; 6752 int rc; 6753 6754 rc = security_sid_to_context(ksec->sid, 6755 &context, &len); 6756 if (!rc) 6757 rc = len; 6758 *_buffer = context; 6759 return rc; 6760 } 6761 6762 #ifdef CONFIG_KEY_NOTIFICATIONS 6763 static int selinux_watch_key(struct key *key) 6764 { 6765 struct key_security_struct *ksec = key->security; 6766 u32 sid = current_sid(); 6767 6768 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); 6769 } 6770 #endif 6771 #endif 6772 6773 #ifdef CONFIG_SECURITY_INFINIBAND 6774 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6775 { 6776 struct common_audit_data ad; 6777 int err; 6778 u32 sid = 0; 6779 struct ib_security_struct *sec = ib_sec; 6780 struct lsm_ibpkey_audit ibpkey; 6781 6782 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6783 if (err) 6784 return err; 6785 6786 ad.type = LSM_AUDIT_DATA_IBPKEY; 6787 ibpkey.subnet_prefix = subnet_prefix; 6788 ibpkey.pkey = pkey_val; 6789 ad.u.ibpkey = &ibpkey; 6790 return avc_has_perm(sec->sid, sid, 6791 SECCLASS_INFINIBAND_PKEY, 6792 INFINIBAND_PKEY__ACCESS, &ad); 6793 } 6794 6795 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6796 u8 port_num) 6797 { 6798 struct common_audit_data ad; 6799 int err; 6800 u32 sid = 0; 6801 struct ib_security_struct *sec = ib_sec; 6802 struct lsm_ibendport_audit ibendport; 6803 6804 err = security_ib_endport_sid(dev_name, port_num, 6805 &sid); 6806 6807 if (err) 6808 return err; 6809 6810 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6811 ibendport.dev_name = dev_name; 6812 ibendport.port = port_num; 6813 ad.u.ibendport = &ibendport; 6814 return avc_has_perm(sec->sid, sid, 6815 SECCLASS_INFINIBAND_ENDPORT, 6816 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6817 } 6818 6819 static int selinux_ib_alloc_security(void **ib_sec) 6820 { 6821 struct ib_security_struct *sec; 6822 6823 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6824 if (!sec) 6825 return -ENOMEM; 6826 sec->sid = current_sid(); 6827 6828 *ib_sec = sec; 6829 return 0; 6830 } 6831 6832 static void selinux_ib_free_security(void *ib_sec) 6833 { 6834 kfree(ib_sec); 6835 } 6836 #endif 6837 6838 #ifdef CONFIG_BPF_SYSCALL 6839 static int selinux_bpf(int cmd, union bpf_attr *attr, 6840 unsigned int size) 6841 { 6842 u32 sid = current_sid(); 6843 int ret; 6844 6845 switch (cmd) { 6846 case BPF_MAP_CREATE: 6847 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6848 NULL); 6849 break; 6850 case BPF_PROG_LOAD: 6851 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6852 NULL); 6853 break; 6854 default: 6855 ret = 0; 6856 break; 6857 } 6858 6859 return ret; 6860 } 6861 6862 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6863 { 6864 u32 av = 0; 6865 6866 if (fmode & FMODE_READ) 6867 av |= BPF__MAP_READ; 6868 if (fmode & FMODE_WRITE) 6869 av |= BPF__MAP_WRITE; 6870 return av; 6871 } 6872 6873 /* This function will check the file pass through unix socket or binder to see 6874 * if it is a bpf related object. And apply corresponding checks on the bpf 6875 * object based on the type. The bpf maps and programs, not like other files and 6876 * socket, are using a shared anonymous inode inside the kernel as their inode. 6877 * So checking that inode cannot identify if the process have privilege to 6878 * access the bpf object and that's why we have to add this additional check in 6879 * selinux_file_receive and selinux_binder_transfer_files. 6880 */ 6881 static int bpf_fd_pass(const struct file *file, u32 sid) 6882 { 6883 struct bpf_security_struct *bpfsec; 6884 struct bpf_prog *prog; 6885 struct bpf_map *map; 6886 int ret; 6887 6888 if (file->f_op == &bpf_map_fops) { 6889 map = file->private_data; 6890 bpfsec = map->security; 6891 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6892 bpf_map_fmode_to_av(file->f_mode), NULL); 6893 if (ret) 6894 return ret; 6895 } else if (file->f_op == &bpf_prog_fops) { 6896 prog = file->private_data; 6897 bpfsec = prog->aux->security; 6898 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6899 BPF__PROG_RUN, NULL); 6900 if (ret) 6901 return ret; 6902 } 6903 return 0; 6904 } 6905 6906 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6907 { 6908 u32 sid = current_sid(); 6909 struct bpf_security_struct *bpfsec; 6910 6911 bpfsec = map->security; 6912 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6913 bpf_map_fmode_to_av(fmode), NULL); 6914 } 6915 6916 static int selinux_bpf_prog(struct bpf_prog *prog) 6917 { 6918 u32 sid = current_sid(); 6919 struct bpf_security_struct *bpfsec; 6920 6921 bpfsec = prog->aux->security; 6922 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, 6923 BPF__PROG_RUN, NULL); 6924 } 6925 6926 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 6927 struct bpf_token *token) 6928 { 6929 struct bpf_security_struct *bpfsec; 6930 6931 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6932 if (!bpfsec) 6933 return -ENOMEM; 6934 6935 bpfsec->sid = current_sid(); 6936 map->security = bpfsec; 6937 6938 return 0; 6939 } 6940 6941 static void selinux_bpf_map_free(struct bpf_map *map) 6942 { 6943 struct bpf_security_struct *bpfsec = map->security; 6944 6945 map->security = NULL; 6946 kfree(bpfsec); 6947 } 6948 6949 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 6950 struct bpf_token *token) 6951 { 6952 struct bpf_security_struct *bpfsec; 6953 6954 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6955 if (!bpfsec) 6956 return -ENOMEM; 6957 6958 bpfsec->sid = current_sid(); 6959 prog->aux->security = bpfsec; 6960 6961 return 0; 6962 } 6963 6964 static void selinux_bpf_prog_free(struct bpf_prog *prog) 6965 { 6966 struct bpf_security_struct *bpfsec = prog->aux->security; 6967 6968 prog->aux->security = NULL; 6969 kfree(bpfsec); 6970 } 6971 6972 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 6973 struct path *path) 6974 { 6975 struct bpf_security_struct *bpfsec; 6976 6977 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6978 if (!bpfsec) 6979 return -ENOMEM; 6980 6981 bpfsec->sid = current_sid(); 6982 token->security = bpfsec; 6983 6984 return 0; 6985 } 6986 6987 static void selinux_bpf_token_free(struct bpf_token *token) 6988 { 6989 struct bpf_security_struct *bpfsec = token->security; 6990 6991 token->security = NULL; 6992 kfree(bpfsec); 6993 } 6994 #endif 6995 6996 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { 6997 .lbs_cred = sizeof(struct task_security_struct), 6998 .lbs_file = sizeof(struct file_security_struct), 6999 .lbs_inode = sizeof(struct inode_security_struct), 7000 .lbs_ipc = sizeof(struct ipc_security_struct), 7001 .lbs_msg_msg = sizeof(struct msg_security_struct), 7002 .lbs_superblock = sizeof(struct superblock_security_struct), 7003 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, 7004 }; 7005 7006 #ifdef CONFIG_PERF_EVENTS 7007 static int selinux_perf_event_open(struct perf_event_attr *attr, int type) 7008 { 7009 u32 requested, sid = current_sid(); 7010 7011 if (type == PERF_SECURITY_OPEN) 7012 requested = PERF_EVENT__OPEN; 7013 else if (type == PERF_SECURITY_CPU) 7014 requested = PERF_EVENT__CPU; 7015 else if (type == PERF_SECURITY_KERNEL) 7016 requested = PERF_EVENT__KERNEL; 7017 else if (type == PERF_SECURITY_TRACEPOINT) 7018 requested = PERF_EVENT__TRACEPOINT; 7019 else 7020 return -EINVAL; 7021 7022 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, 7023 requested, NULL); 7024 } 7025 7026 static int selinux_perf_event_alloc(struct perf_event *event) 7027 { 7028 struct perf_event_security_struct *perfsec; 7029 7030 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); 7031 if (!perfsec) 7032 return -ENOMEM; 7033 7034 perfsec->sid = current_sid(); 7035 event->security = perfsec; 7036 7037 return 0; 7038 } 7039 7040 static void selinux_perf_event_free(struct perf_event *event) 7041 { 7042 struct perf_event_security_struct *perfsec = event->security; 7043 7044 event->security = NULL; 7045 kfree(perfsec); 7046 } 7047 7048 static int selinux_perf_event_read(struct perf_event *event) 7049 { 7050 struct perf_event_security_struct *perfsec = event->security; 7051 u32 sid = current_sid(); 7052 7053 return avc_has_perm(sid, perfsec->sid, 7054 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); 7055 } 7056 7057 static int selinux_perf_event_write(struct perf_event *event) 7058 { 7059 struct perf_event_security_struct *perfsec = event->security; 7060 u32 sid = current_sid(); 7061 7062 return avc_has_perm(sid, perfsec->sid, 7063 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); 7064 } 7065 #endif 7066 7067 #ifdef CONFIG_IO_URING 7068 /** 7069 * selinux_uring_override_creds - check the requested cred override 7070 * @new: the target creds 7071 * 7072 * Check to see if the current task is allowed to override it's credentials 7073 * to service an io_uring operation. 7074 */ 7075 static int selinux_uring_override_creds(const struct cred *new) 7076 { 7077 return avc_has_perm(current_sid(), cred_sid(new), 7078 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); 7079 } 7080 7081 /** 7082 * selinux_uring_sqpoll - check if a io_uring polling thread can be created 7083 * 7084 * Check to see if the current task is allowed to create a new io_uring 7085 * kernel polling thread. 7086 */ 7087 static int selinux_uring_sqpoll(void) 7088 { 7089 u32 sid = current_sid(); 7090 7091 return avc_has_perm(sid, sid, 7092 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); 7093 } 7094 7095 /** 7096 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed 7097 * @ioucmd: the io_uring command structure 7098 * 7099 * Check to see if the current domain is allowed to execute an 7100 * IORING_OP_URING_CMD against the device/file specified in @ioucmd. 7101 * 7102 */ 7103 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) 7104 { 7105 struct file *file = ioucmd->file; 7106 struct inode *inode = file_inode(file); 7107 struct inode_security_struct *isec = selinux_inode(inode); 7108 struct common_audit_data ad; 7109 7110 ad.type = LSM_AUDIT_DATA_FILE; 7111 ad.u.file = file; 7112 7113 return avc_has_perm(current_sid(), isec->sid, 7114 SECCLASS_IO_URING, IO_URING__CMD, &ad); 7115 } 7116 #endif /* CONFIG_IO_URING */ 7117 7118 static const struct lsm_id selinux_lsmid = { 7119 .name = "selinux", 7120 .id = LSM_ID_SELINUX, 7121 }; 7122 7123 /* 7124 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: 7125 * 1. any hooks that don't belong to (2.) or (3.) below, 7126 * 2. hooks that both access structures allocated by other hooks, and allocate 7127 * structures that can be later accessed by other hooks (mostly "cloning" 7128 * hooks), 7129 * 3. hooks that only allocate structures that can be later accessed by other 7130 * hooks ("allocating" hooks). 7131 * 7132 * Please follow block comment delimiters in the list to keep this order. 7133 */ 7134 static struct security_hook_list selinux_hooks[] __ro_after_init = { 7135 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 7136 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 7137 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 7138 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 7139 7140 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 7141 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 7142 LSM_HOOK_INIT(capget, selinux_capget), 7143 LSM_HOOK_INIT(capset, selinux_capset), 7144 LSM_HOOK_INIT(capable, selinux_capable), 7145 LSM_HOOK_INIT(quotactl, selinux_quotactl), 7146 LSM_HOOK_INIT(quota_on, selinux_quota_on), 7147 LSM_HOOK_INIT(syslog, selinux_syslog), 7148 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 7149 7150 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 7151 7152 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), 7153 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 7154 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 7155 7156 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), 7157 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), 7158 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 7159 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 7160 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 7161 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 7162 LSM_HOOK_INIT(sb_mount, selinux_mount), 7163 LSM_HOOK_INIT(sb_umount, selinux_umount), 7164 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 7165 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 7166 7167 LSM_HOOK_INIT(move_mount, selinux_move_mount), 7168 7169 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 7170 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 7171 7172 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 7173 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 7174 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), 7175 LSM_HOOK_INIT(inode_create, selinux_inode_create), 7176 LSM_HOOK_INIT(inode_link, selinux_inode_link), 7177 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 7178 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 7179 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 7180 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 7181 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 7182 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 7183 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 7184 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 7185 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 7186 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 7187 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 7188 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 7189 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 7190 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 7191 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 7192 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 7193 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), 7194 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), 7195 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), 7196 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 7197 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 7198 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 7199 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 7200 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 7201 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 7202 LSM_HOOK_INIT(path_notify, selinux_path_notify), 7203 7204 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), 7205 7206 LSM_HOOK_INIT(file_permission, selinux_file_permission), 7207 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 7208 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 7209 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat), 7210 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 7211 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 7212 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 7213 LSM_HOOK_INIT(file_lock, selinux_file_lock), 7214 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 7215 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 7216 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 7217 LSM_HOOK_INIT(file_receive, selinux_file_receive), 7218 7219 LSM_HOOK_INIT(file_open, selinux_file_open), 7220 7221 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 7222 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 7223 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 7224 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), 7225 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 7226 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 7227 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 7228 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), 7229 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 7230 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 7231 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 7232 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 7233 LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), 7234 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), 7235 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 7236 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 7237 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 7238 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 7239 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 7240 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 7241 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 7242 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 7243 LSM_HOOK_INIT(task_kill, selinux_task_kill), 7244 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 7245 LSM_HOOK_INIT(userns_create, selinux_userns_create), 7246 7247 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 7248 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 7249 7250 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 7251 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 7252 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 7253 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 7254 7255 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 7256 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 7257 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 7258 7259 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 7260 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 7261 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 7262 7263 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 7264 7265 LSM_HOOK_INIT(getselfattr, selinux_getselfattr), 7266 LSM_HOOK_INIT(setselfattr, selinux_setselfattr), 7267 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 7268 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 7269 7270 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 7271 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 7272 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 7273 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 7274 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 7275 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 7276 7277 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 7278 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 7279 7280 LSM_HOOK_INIT(socket_create, selinux_socket_create), 7281 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 7282 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), 7283 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 7284 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 7285 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 7286 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 7287 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 7288 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 7289 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 7290 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 7291 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 7292 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7293 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7294 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7295 LSM_HOOK_INIT(socket_getpeersec_stream, 7296 selinux_socket_getpeersec_stream), 7297 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7298 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7299 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7300 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7301 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7302 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7303 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7304 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7305 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), 7306 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), 7307 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7308 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7309 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7310 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7311 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7312 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7313 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7314 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7315 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7316 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7317 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7318 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7319 #ifdef CONFIG_SECURITY_INFINIBAND 7320 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7321 LSM_HOOK_INIT(ib_endport_manage_subnet, 7322 selinux_ib_endport_manage_subnet), 7323 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7324 #endif 7325 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7326 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7327 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7328 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7329 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7330 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7331 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7332 selinux_xfrm_state_pol_flow_match), 7333 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7334 #endif 7335 7336 #ifdef CONFIG_KEYS 7337 LSM_HOOK_INIT(key_free, selinux_key_free), 7338 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7339 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7340 #ifdef CONFIG_KEY_NOTIFICATIONS 7341 LSM_HOOK_INIT(watch_key, selinux_watch_key), 7342 #endif 7343 #endif 7344 7345 #ifdef CONFIG_AUDIT 7346 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7347 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7348 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7349 #endif 7350 7351 #ifdef CONFIG_BPF_SYSCALL 7352 LSM_HOOK_INIT(bpf, selinux_bpf), 7353 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7354 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7355 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free), 7356 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free), 7357 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free), 7358 #endif 7359 7360 #ifdef CONFIG_PERF_EVENTS 7361 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), 7362 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), 7363 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), 7364 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), 7365 #endif 7366 7367 #ifdef CONFIG_IO_URING 7368 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), 7369 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), 7370 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), 7371 #endif 7372 7373 /* 7374 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE 7375 */ 7376 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), 7377 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), 7378 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), 7379 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), 7380 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7381 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7382 #endif 7383 7384 /* 7385 * PUT "ALLOCATING" HOOKS HERE 7386 */ 7387 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 7388 LSM_HOOK_INIT(msg_queue_alloc_security, 7389 selinux_msg_queue_alloc_security), 7390 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 7391 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 7392 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 7393 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 7394 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 7395 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 7396 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7397 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7398 #ifdef CONFIG_SECURITY_INFINIBAND 7399 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7400 #endif 7401 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7402 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7403 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7404 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7405 selinux_xfrm_state_alloc_acquire), 7406 #endif 7407 #ifdef CONFIG_KEYS 7408 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7409 #endif 7410 #ifdef CONFIG_AUDIT 7411 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7412 #endif 7413 #ifdef CONFIG_BPF_SYSCALL 7414 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create), 7415 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load), 7416 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create), 7417 #endif 7418 #ifdef CONFIG_PERF_EVENTS 7419 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), 7420 #endif 7421 }; 7422 7423 static __init int selinux_init(void) 7424 { 7425 pr_info("SELinux: Initializing.\n"); 7426 7427 memset(&selinux_state, 0, sizeof(selinux_state)); 7428 enforcing_set(selinux_enforcing_boot); 7429 selinux_avc_init(); 7430 mutex_init(&selinux_state.status_lock); 7431 mutex_init(&selinux_state.policy_mutex); 7432 7433 /* Set the security state for the initial task. */ 7434 cred_init_security(); 7435 7436 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7437 if (!default_noexec) 7438 pr_notice("SELinux: virtual memory is executable by default\n"); 7439 7440 avc_init(); 7441 7442 avtab_cache_init(); 7443 7444 ebitmap_cache_init(); 7445 7446 hashtab_cache_init(); 7447 7448 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), 7449 &selinux_lsmid); 7450 7451 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7452 panic("SELinux: Unable to register AVC netcache callback\n"); 7453 7454 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7455 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7456 7457 if (selinux_enforcing_boot) 7458 pr_debug("SELinux: Starting in enforcing mode\n"); 7459 else 7460 pr_debug("SELinux: Starting in permissive mode\n"); 7461 7462 fs_validate_description("selinux", selinux_fs_parameters); 7463 7464 return 0; 7465 } 7466 7467 static void delayed_superblock_init(struct super_block *sb, void *unused) 7468 { 7469 selinux_set_mnt_opts(sb, NULL, 0, NULL); 7470 } 7471 7472 void selinux_complete_init(void) 7473 { 7474 pr_debug("SELinux: Completing initialization.\n"); 7475 7476 /* Set up any superblocks initialized prior to the policy load. */ 7477 pr_debug("SELinux: Setting up existing superblocks.\n"); 7478 iterate_supers(delayed_superblock_init, NULL); 7479 } 7480 7481 /* SELinux requires early initialization in order to label 7482 all processes and objects when they are created. */ 7483 DEFINE_LSM(selinux) = { 7484 .name = "selinux", 7485 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 7486 .enabled = &selinux_enabled_boot, 7487 .blobs = &selinux_blob_sizes, 7488 .init = selinux_init, 7489 }; 7490 7491 #if defined(CONFIG_NETFILTER) 7492 static const struct nf_hook_ops selinux_nf_ops[] = { 7493 { 7494 .hook = selinux_ip_postroute, 7495 .pf = NFPROTO_IPV4, 7496 .hooknum = NF_INET_POST_ROUTING, 7497 .priority = NF_IP_PRI_SELINUX_LAST, 7498 }, 7499 { 7500 .hook = selinux_ip_forward, 7501 .pf = NFPROTO_IPV4, 7502 .hooknum = NF_INET_FORWARD, 7503 .priority = NF_IP_PRI_SELINUX_FIRST, 7504 }, 7505 { 7506 .hook = selinux_ip_output, 7507 .pf = NFPROTO_IPV4, 7508 .hooknum = NF_INET_LOCAL_OUT, 7509 .priority = NF_IP_PRI_SELINUX_FIRST, 7510 }, 7511 #if IS_ENABLED(CONFIG_IPV6) 7512 { 7513 .hook = selinux_ip_postroute, 7514 .pf = NFPROTO_IPV6, 7515 .hooknum = NF_INET_POST_ROUTING, 7516 .priority = NF_IP6_PRI_SELINUX_LAST, 7517 }, 7518 { 7519 .hook = selinux_ip_forward, 7520 .pf = NFPROTO_IPV6, 7521 .hooknum = NF_INET_FORWARD, 7522 .priority = NF_IP6_PRI_SELINUX_FIRST, 7523 }, 7524 { 7525 .hook = selinux_ip_output, 7526 .pf = NFPROTO_IPV6, 7527 .hooknum = NF_INET_LOCAL_OUT, 7528 .priority = NF_IP6_PRI_SELINUX_FIRST, 7529 }, 7530 #endif /* IPV6 */ 7531 }; 7532 7533 static int __net_init selinux_nf_register(struct net *net) 7534 { 7535 return nf_register_net_hooks(net, selinux_nf_ops, 7536 ARRAY_SIZE(selinux_nf_ops)); 7537 } 7538 7539 static void __net_exit selinux_nf_unregister(struct net *net) 7540 { 7541 nf_unregister_net_hooks(net, selinux_nf_ops, 7542 ARRAY_SIZE(selinux_nf_ops)); 7543 } 7544 7545 static struct pernet_operations selinux_net_ops = { 7546 .init = selinux_nf_register, 7547 .exit = selinux_nf_unregister, 7548 }; 7549 7550 static int __init selinux_nf_ip_init(void) 7551 { 7552 int err; 7553 7554 if (!selinux_enabled_boot) 7555 return 0; 7556 7557 pr_debug("SELinux: Registering netfilter hooks\n"); 7558 7559 err = register_pernet_subsys(&selinux_net_ops); 7560 if (err) 7561 panic("SELinux: register_pernet_subsys: error %d\n", err); 7562 7563 return 0; 7564 } 7565 __initcall(selinux_nf_ip_init); 7566 #endif /* CONFIG_NETFILTER */ 7567