1 /* 2 * NSA Security-Enhanced Linux (SELinux) security module 3 * 4 * This file contains the SELinux hook function implementations. 5 * 6 * Authors: Stephen Smalley, <sds@tycho.nsa.gov> 7 * Chris Vance, <cvance@nai.com> 8 * Wayne Salamon, <wsalamon@nai.com> 9 * James Morris <jmorris@redhat.com> 10 * 11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> 13 * Eric Paris <eparis@redhat.com> 14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 15 * <dgoeddel@trustedcs.com> 16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. 17 * Paul Moore <paul@paul-moore.com> 18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 19 * Yuichi Nakamura <ynakam@hitachisoft.jp> 20 * Copyright (C) 2016 Mellanox Technologies 21 * 22 * This program is free software; you can redistribute it and/or modify 23 * it under the terms of the GNU General Public License version 2, 24 * as published by the Free Software Foundation. 25 */ 26 27 #include <linux/init.h> 28 #include <linux/kd.h> 29 #include <linux/kernel.h> 30 #include <linux/tracehook.h> 31 #include <linux/errno.h> 32 #include <linux/sched/signal.h> 33 #include <linux/sched/task.h> 34 #include <linux/lsm_hooks.h> 35 #include <linux/xattr.h> 36 #include <linux/capability.h> 37 #include <linux/unistd.h> 38 #include <linux/mm.h> 39 #include <linux/mman.h> 40 #include <linux/slab.h> 41 #include <linux/pagemap.h> 42 #include <linux/proc_fs.h> 43 #include <linux/swap.h> 44 #include <linux/spinlock.h> 45 #include <linux/syscalls.h> 46 #include <linux/dcache.h> 47 #include <linux/file.h> 48 #include <linux/fdtable.h> 49 #include <linux/namei.h> 50 #include <linux/mount.h> 51 #include <linux/netfilter_ipv4.h> 52 #include <linux/netfilter_ipv6.h> 53 #include <linux/tty.h> 54 #include <net/icmp.h> 55 #include <net/ip.h> /* for local_port_range[] */ 56 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 57 #include <net/inet_connection_sock.h> 58 #include <net/net_namespace.h> 59 #include <net/netlabel.h> 60 #include <linux/uaccess.h> 61 #include <asm/ioctls.h> 62 #include <linux/atomic.h> 63 #include <linux/bitops.h> 64 #include <linux/interrupt.h> 65 #include <linux/netdevice.h> /* for network interface checks */ 66 #include <net/netlink.h> 67 #include <linux/tcp.h> 68 #include <linux/udp.h> 69 #include <linux/dccp.h> 70 #include <linux/sctp.h> 71 #include <net/sctp/structs.h> 72 #include <linux/quota.h> 73 #include <linux/un.h> /* for Unix socket types */ 74 #include <net/af_unix.h> /* for Unix socket types */ 75 #include <linux/parser.h> 76 #include <linux/nfs_mount.h> 77 #include <net/ipv6.h> 78 #include <linux/hugetlb.h> 79 #include <linux/personality.h> 80 #include <linux/audit.h> 81 #include <linux/string.h> 82 #include <linux/selinux.h> 83 #include <linux/mutex.h> 84 #include <linux/posix-timers.h> 85 #include <linux/syslog.h> 86 #include <linux/user_namespace.h> 87 #include <linux/export.h> 88 #include <linux/msg.h> 89 #include <linux/shm.h> 90 #include <linux/bpf.h> 91 92 #include "avc.h" 93 #include "objsec.h" 94 #include "netif.h" 95 #include "netnode.h" 96 #include "netport.h" 97 #include "ibpkey.h" 98 #include "xfrm.h" 99 #include "netlabel.h" 100 #include "audit.h" 101 #include "avc_ss.h" 102 103 struct selinux_state selinux_state; 104 105 /* SECMARK reference count */ 106 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 107 108 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 109 static int selinux_enforcing_boot; 110 111 static int __init enforcing_setup(char *str) 112 { 113 unsigned long enforcing; 114 if (!kstrtoul(str, 0, &enforcing)) 115 selinux_enforcing_boot = enforcing ? 1 : 0; 116 return 1; 117 } 118 __setup("enforcing=", enforcing_setup); 119 #else 120 #define selinux_enforcing_boot 1 121 #endif 122 123 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 124 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 125 126 static int __init selinux_enabled_setup(char *str) 127 { 128 unsigned long enabled; 129 if (!kstrtoul(str, 0, &enabled)) 130 selinux_enabled = enabled ? 1 : 0; 131 return 1; 132 } 133 __setup("selinux=", selinux_enabled_setup); 134 #else 135 int selinux_enabled = 1; 136 #endif 137 138 static unsigned int selinux_checkreqprot_boot = 139 CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; 140 141 static int __init checkreqprot_setup(char *str) 142 { 143 unsigned long checkreqprot; 144 145 if (!kstrtoul(str, 0, &checkreqprot)) 146 selinux_checkreqprot_boot = checkreqprot ? 1 : 0; 147 return 1; 148 } 149 __setup("checkreqprot=", checkreqprot_setup); 150 151 static struct kmem_cache *sel_inode_cache; 152 static struct kmem_cache *file_security_cache; 153 154 /** 155 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 156 * 157 * Description: 158 * This function checks the SECMARK reference counter to see if any SECMARK 159 * targets are currently configured, if the reference counter is greater than 160 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 161 * enabled, false (0) if SECMARK is disabled. If the always_check_network 162 * policy capability is enabled, SECMARK is always considered enabled. 163 * 164 */ 165 static int selinux_secmark_enabled(void) 166 { 167 return (selinux_policycap_alwaysnetwork() || 168 atomic_read(&selinux_secmark_refcount)); 169 } 170 171 /** 172 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 173 * 174 * Description: 175 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 176 * (1) if any are enabled or false (0) if neither are enabled. If the 177 * always_check_network policy capability is enabled, peer labeling 178 * is always considered enabled. 179 * 180 */ 181 static int selinux_peerlbl_enabled(void) 182 { 183 return (selinux_policycap_alwaysnetwork() || 184 netlbl_enabled() || selinux_xfrm_enabled()); 185 } 186 187 static int selinux_netcache_avc_callback(u32 event) 188 { 189 if (event == AVC_CALLBACK_RESET) { 190 sel_netif_flush(); 191 sel_netnode_flush(); 192 sel_netport_flush(); 193 synchronize_net(); 194 } 195 return 0; 196 } 197 198 static int selinux_lsm_notifier_avc_callback(u32 event) 199 { 200 if (event == AVC_CALLBACK_RESET) { 201 sel_ib_pkey_flush(); 202 call_lsm_notifier(LSM_POLICY_CHANGE, NULL); 203 } 204 205 return 0; 206 } 207 208 /* 209 * initialise the security for the init task 210 */ 211 static void cred_init_security(void) 212 { 213 struct cred *cred = (struct cred *) current->real_cred; 214 struct task_security_struct *tsec; 215 216 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 217 if (!tsec) 218 panic("SELinux: Failed to initialize initial task.\n"); 219 220 tsec->osid = tsec->sid = SECINITSID_KERNEL; 221 cred->security = tsec; 222 } 223 224 /* 225 * get the security ID of a set of credentials 226 */ 227 static inline u32 cred_sid(const struct cred *cred) 228 { 229 const struct task_security_struct *tsec; 230 231 tsec = cred->security; 232 return tsec->sid; 233 } 234 235 /* 236 * get the objective security ID of a task 237 */ 238 static inline u32 task_sid(const struct task_struct *task) 239 { 240 u32 sid; 241 242 rcu_read_lock(); 243 sid = cred_sid(__task_cred(task)); 244 rcu_read_unlock(); 245 return sid; 246 } 247 248 /* Allocate and free functions for each kind of security blob. */ 249 250 static int inode_alloc_security(struct inode *inode) 251 { 252 struct inode_security_struct *isec; 253 u32 sid = current_sid(); 254 255 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 256 if (!isec) 257 return -ENOMEM; 258 259 spin_lock_init(&isec->lock); 260 INIT_LIST_HEAD(&isec->list); 261 isec->inode = inode; 262 isec->sid = SECINITSID_UNLABELED; 263 isec->sclass = SECCLASS_FILE; 264 isec->task_sid = sid; 265 isec->initialized = LABEL_INVALID; 266 inode->i_security = isec; 267 268 return 0; 269 } 270 271 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 272 273 /* 274 * Try reloading inode security labels that have been marked as invalid. The 275 * @may_sleep parameter indicates when sleeping and thus reloading labels is 276 * allowed; when set to false, returns -ECHILD when the label is 277 * invalid. The @opt_dentry parameter should be set to a dentry of the inode; 278 * when no dentry is available, set it to NULL instead. 279 */ 280 static int __inode_security_revalidate(struct inode *inode, 281 struct dentry *opt_dentry, 282 bool may_sleep) 283 { 284 struct inode_security_struct *isec = inode->i_security; 285 286 might_sleep_if(may_sleep); 287 288 if (selinux_state.initialized && 289 isec->initialized != LABEL_INITIALIZED) { 290 if (!may_sleep) 291 return -ECHILD; 292 293 /* 294 * Try reloading the inode security label. This will fail if 295 * @opt_dentry is NULL and no dentry for this inode can be 296 * found; in that case, continue using the old label. 297 */ 298 inode_doinit_with_dentry(inode, opt_dentry); 299 } 300 return 0; 301 } 302 303 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 304 { 305 return inode->i_security; 306 } 307 308 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 309 { 310 int error; 311 312 error = __inode_security_revalidate(inode, NULL, !rcu); 313 if (error) 314 return ERR_PTR(error); 315 return inode->i_security; 316 } 317 318 /* 319 * Get the security label of an inode. 320 */ 321 static struct inode_security_struct *inode_security(struct inode *inode) 322 { 323 __inode_security_revalidate(inode, NULL, true); 324 return inode->i_security; 325 } 326 327 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 328 { 329 struct inode *inode = d_backing_inode(dentry); 330 331 return inode->i_security; 332 } 333 334 /* 335 * Get the security label of a dentry's backing inode. 336 */ 337 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 338 { 339 struct inode *inode = d_backing_inode(dentry); 340 341 __inode_security_revalidate(inode, dentry, true); 342 return inode->i_security; 343 } 344 345 static void inode_free_rcu(struct rcu_head *head) 346 { 347 struct inode_security_struct *isec; 348 349 isec = container_of(head, struct inode_security_struct, rcu); 350 kmem_cache_free(sel_inode_cache, isec); 351 } 352 353 static void inode_free_security(struct inode *inode) 354 { 355 struct inode_security_struct *isec = inode->i_security; 356 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 357 358 /* 359 * As not all inode security structures are in a list, we check for 360 * empty list outside of the lock to make sure that we won't waste 361 * time taking a lock doing nothing. 362 * 363 * The list_del_init() function can be safely called more than once. 364 * It should not be possible for this function to be called with 365 * concurrent list_add(), but for better safety against future changes 366 * in the code, we use list_empty_careful() here. 367 */ 368 if (!list_empty_careful(&isec->list)) { 369 spin_lock(&sbsec->isec_lock); 370 list_del_init(&isec->list); 371 spin_unlock(&sbsec->isec_lock); 372 } 373 374 /* 375 * The inode may still be referenced in a path walk and 376 * a call to selinux_inode_permission() can be made 377 * after inode_free_security() is called. Ideally, the VFS 378 * wouldn't do this, but fixing that is a much harder 379 * job. For now, simply free the i_security via RCU, and 380 * leave the current inode->i_security pointer intact. 381 * The inode will be freed after the RCU grace period too. 382 */ 383 call_rcu(&isec->rcu, inode_free_rcu); 384 } 385 386 static int file_alloc_security(struct file *file) 387 { 388 struct file_security_struct *fsec; 389 u32 sid = current_sid(); 390 391 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); 392 if (!fsec) 393 return -ENOMEM; 394 395 fsec->sid = sid; 396 fsec->fown_sid = sid; 397 file->f_security = fsec; 398 399 return 0; 400 } 401 402 static void file_free_security(struct file *file) 403 { 404 struct file_security_struct *fsec = file->f_security; 405 file->f_security = NULL; 406 kmem_cache_free(file_security_cache, fsec); 407 } 408 409 static int superblock_alloc_security(struct super_block *sb) 410 { 411 struct superblock_security_struct *sbsec; 412 413 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 414 if (!sbsec) 415 return -ENOMEM; 416 417 mutex_init(&sbsec->lock); 418 INIT_LIST_HEAD(&sbsec->isec_head); 419 spin_lock_init(&sbsec->isec_lock); 420 sbsec->sb = sb; 421 sbsec->sid = SECINITSID_UNLABELED; 422 sbsec->def_sid = SECINITSID_FILE; 423 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 424 sb->s_security = sbsec; 425 426 return 0; 427 } 428 429 static void superblock_free_security(struct super_block *sb) 430 { 431 struct superblock_security_struct *sbsec = sb->s_security; 432 sb->s_security = NULL; 433 kfree(sbsec); 434 } 435 436 static inline int inode_doinit(struct inode *inode) 437 { 438 return inode_doinit_with_dentry(inode, NULL); 439 } 440 441 enum { 442 Opt_error = -1, 443 Opt_context = 1, 444 Opt_fscontext = 2, 445 Opt_defcontext = 3, 446 Opt_rootcontext = 4, 447 Opt_labelsupport = 5, 448 Opt_nextmntopt = 6, 449 }; 450 451 #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) 452 453 static const match_table_t tokens = { 454 {Opt_context, CONTEXT_STR "%s"}, 455 {Opt_fscontext, FSCONTEXT_STR "%s"}, 456 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 457 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 458 {Opt_labelsupport, LABELSUPP_STR}, 459 {Opt_error, NULL}, 460 }; 461 462 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 463 464 static int may_context_mount_sb_relabel(u32 sid, 465 struct superblock_security_struct *sbsec, 466 const struct cred *cred) 467 { 468 const struct task_security_struct *tsec = cred->security; 469 int rc; 470 471 rc = avc_has_perm(&selinux_state, 472 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 473 FILESYSTEM__RELABELFROM, NULL); 474 if (rc) 475 return rc; 476 477 rc = avc_has_perm(&selinux_state, 478 tsec->sid, sid, SECCLASS_FILESYSTEM, 479 FILESYSTEM__RELABELTO, NULL); 480 return rc; 481 } 482 483 static int may_context_mount_inode_relabel(u32 sid, 484 struct superblock_security_struct *sbsec, 485 const struct cred *cred) 486 { 487 const struct task_security_struct *tsec = cred->security; 488 int rc; 489 rc = avc_has_perm(&selinux_state, 490 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 491 FILESYSTEM__RELABELFROM, NULL); 492 if (rc) 493 return rc; 494 495 rc = avc_has_perm(&selinux_state, 496 sid, sbsec->sid, SECCLASS_FILESYSTEM, 497 FILESYSTEM__ASSOCIATE, NULL); 498 return rc; 499 } 500 501 static int selinux_is_sblabel_mnt(struct super_block *sb) 502 { 503 struct superblock_security_struct *sbsec = sb->s_security; 504 505 return sbsec->behavior == SECURITY_FS_USE_XATTR || 506 sbsec->behavior == SECURITY_FS_USE_TRANS || 507 sbsec->behavior == SECURITY_FS_USE_TASK || 508 sbsec->behavior == SECURITY_FS_USE_NATIVE || 509 /* Special handling. Genfs but also in-core setxattr handler */ 510 !strcmp(sb->s_type->name, "sysfs") || 511 !strcmp(sb->s_type->name, "pstore") || 512 !strcmp(sb->s_type->name, "debugfs") || 513 !strcmp(sb->s_type->name, "tracefs") || 514 !strcmp(sb->s_type->name, "rootfs") || 515 (selinux_policycap_cgroupseclabel() && 516 (!strcmp(sb->s_type->name, "cgroup") || 517 !strcmp(sb->s_type->name, "cgroup2"))); 518 } 519 520 static int sb_finish_set_opts(struct super_block *sb) 521 { 522 struct superblock_security_struct *sbsec = sb->s_security; 523 struct dentry *root = sb->s_root; 524 struct inode *root_inode = d_backing_inode(root); 525 int rc = 0; 526 527 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 528 /* Make sure that the xattr handler exists and that no 529 error other than -ENODATA is returned by getxattr on 530 the root directory. -ENODATA is ok, as this may be 531 the first boot of the SELinux kernel before we have 532 assigned xattr values to the filesystem. */ 533 if (!(root_inode->i_opflags & IOP_XATTR)) { 534 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 535 "xattr support\n", sb->s_id, sb->s_type->name); 536 rc = -EOPNOTSUPP; 537 goto out; 538 } 539 540 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 541 if (rc < 0 && rc != -ENODATA) { 542 if (rc == -EOPNOTSUPP) 543 printk(KERN_WARNING "SELinux: (dev %s, type " 544 "%s) has no security xattr handler\n", 545 sb->s_id, sb->s_type->name); 546 else 547 printk(KERN_WARNING "SELinux: (dev %s, type " 548 "%s) getxattr errno %d\n", sb->s_id, 549 sb->s_type->name, -rc); 550 goto out; 551 } 552 } 553 554 sbsec->flags |= SE_SBINITIALIZED; 555 556 /* 557 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply 558 * leave the flag untouched because sb_clone_mnt_opts might be handing 559 * us a superblock that needs the flag to be cleared. 560 */ 561 if (selinux_is_sblabel_mnt(sb)) 562 sbsec->flags |= SBLABEL_MNT; 563 else 564 sbsec->flags &= ~SBLABEL_MNT; 565 566 /* Initialize the root inode. */ 567 rc = inode_doinit_with_dentry(root_inode, root); 568 569 /* Initialize any other inodes associated with the superblock, e.g. 570 inodes created prior to initial policy load or inodes created 571 during get_sb by a pseudo filesystem that directly 572 populates itself. */ 573 spin_lock(&sbsec->isec_lock); 574 next_inode: 575 if (!list_empty(&sbsec->isec_head)) { 576 struct inode_security_struct *isec = 577 list_entry(sbsec->isec_head.next, 578 struct inode_security_struct, list); 579 struct inode *inode = isec->inode; 580 list_del_init(&isec->list); 581 spin_unlock(&sbsec->isec_lock); 582 inode = igrab(inode); 583 if (inode) { 584 if (!IS_PRIVATE(inode)) 585 inode_doinit(inode); 586 iput(inode); 587 } 588 spin_lock(&sbsec->isec_lock); 589 goto next_inode; 590 } 591 spin_unlock(&sbsec->isec_lock); 592 out: 593 return rc; 594 } 595 596 /* 597 * This function should allow an FS to ask what it's mount security 598 * options were so it can use those later for submounts, displaying 599 * mount options, or whatever. 600 */ 601 static int selinux_get_mnt_opts(const struct super_block *sb, 602 struct security_mnt_opts *opts) 603 { 604 int rc = 0, i; 605 struct superblock_security_struct *sbsec = sb->s_security; 606 char *context = NULL; 607 u32 len; 608 char tmp; 609 610 security_init_mnt_opts(opts); 611 612 if (!(sbsec->flags & SE_SBINITIALIZED)) 613 return -EINVAL; 614 615 if (!selinux_state.initialized) 616 return -EINVAL; 617 618 /* make sure we always check enough bits to cover the mask */ 619 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); 620 621 tmp = sbsec->flags & SE_MNTMASK; 622 /* count the number of mount options for this sb */ 623 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { 624 if (tmp & 0x01) 625 opts->num_mnt_opts++; 626 tmp >>= 1; 627 } 628 /* Check if the Label support flag is set */ 629 if (sbsec->flags & SBLABEL_MNT) 630 opts->num_mnt_opts++; 631 632 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 633 if (!opts->mnt_opts) { 634 rc = -ENOMEM; 635 goto out_free; 636 } 637 638 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 639 if (!opts->mnt_opts_flags) { 640 rc = -ENOMEM; 641 goto out_free; 642 } 643 644 i = 0; 645 if (sbsec->flags & FSCONTEXT_MNT) { 646 rc = security_sid_to_context(&selinux_state, sbsec->sid, 647 &context, &len); 648 if (rc) 649 goto out_free; 650 opts->mnt_opts[i] = context; 651 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 652 } 653 if (sbsec->flags & CONTEXT_MNT) { 654 rc = security_sid_to_context(&selinux_state, 655 sbsec->mntpoint_sid, 656 &context, &len); 657 if (rc) 658 goto out_free; 659 opts->mnt_opts[i] = context; 660 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 661 } 662 if (sbsec->flags & DEFCONTEXT_MNT) { 663 rc = security_sid_to_context(&selinux_state, sbsec->def_sid, 664 &context, &len); 665 if (rc) 666 goto out_free; 667 opts->mnt_opts[i] = context; 668 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 669 } 670 if (sbsec->flags & ROOTCONTEXT_MNT) { 671 struct dentry *root = sbsec->sb->s_root; 672 struct inode_security_struct *isec = backing_inode_security(root); 673 674 rc = security_sid_to_context(&selinux_state, isec->sid, 675 &context, &len); 676 if (rc) 677 goto out_free; 678 opts->mnt_opts[i] = context; 679 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 680 } 681 if (sbsec->flags & SBLABEL_MNT) { 682 opts->mnt_opts[i] = NULL; 683 opts->mnt_opts_flags[i++] = SBLABEL_MNT; 684 } 685 686 BUG_ON(i != opts->num_mnt_opts); 687 688 return 0; 689 690 out_free: 691 security_free_mnt_opts(opts); 692 return rc; 693 } 694 695 static int bad_option(struct superblock_security_struct *sbsec, char flag, 696 u32 old_sid, u32 new_sid) 697 { 698 char mnt_flags = sbsec->flags & SE_MNTMASK; 699 700 /* check if the old mount command had the same options */ 701 if (sbsec->flags & SE_SBINITIALIZED) 702 if (!(sbsec->flags & flag) || 703 (old_sid != new_sid)) 704 return 1; 705 706 /* check if we were passed the same options twice, 707 * aka someone passed context=a,context=b 708 */ 709 if (!(sbsec->flags & SE_SBINITIALIZED)) 710 if (mnt_flags & flag) 711 return 1; 712 return 0; 713 } 714 715 /* 716 * Allow filesystems with binary mount data to explicitly set mount point 717 * labeling information. 718 */ 719 static int selinux_set_mnt_opts(struct super_block *sb, 720 struct security_mnt_opts *opts, 721 unsigned long kern_flags, 722 unsigned long *set_kern_flags) 723 { 724 const struct cred *cred = current_cred(); 725 int rc = 0, i; 726 struct superblock_security_struct *sbsec = sb->s_security; 727 const char *name = sb->s_type->name; 728 struct dentry *root = sbsec->sb->s_root; 729 struct inode_security_struct *root_isec; 730 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 731 u32 defcontext_sid = 0; 732 char **mount_options = opts->mnt_opts; 733 int *flags = opts->mnt_opts_flags; 734 int num_opts = opts->num_mnt_opts; 735 736 mutex_lock(&sbsec->lock); 737 738 if (!selinux_state.initialized) { 739 if (!num_opts) { 740 /* Defer initialization until selinux_complete_init, 741 after the initial policy is loaded and the security 742 server is ready to handle calls. */ 743 goto out; 744 } 745 rc = -EINVAL; 746 printk(KERN_WARNING "SELinux: Unable to set superblock options " 747 "before the security server is initialized\n"); 748 goto out; 749 } 750 if (kern_flags && !set_kern_flags) { 751 /* Specifying internal flags without providing a place to 752 * place the results is not allowed */ 753 rc = -EINVAL; 754 goto out; 755 } 756 757 /* 758 * Binary mount data FS will come through this function twice. Once 759 * from an explicit call and once from the generic calls from the vfs. 760 * Since the generic VFS calls will not contain any security mount data 761 * we need to skip the double mount verification. 762 * 763 * This does open a hole in which we will not notice if the first 764 * mount using this sb set explict options and a second mount using 765 * this sb does not set any security options. (The first options 766 * will be used for both mounts) 767 */ 768 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 769 && (num_opts == 0)) 770 goto out; 771 772 root_isec = backing_inode_security_novalidate(root); 773 774 /* 775 * parse the mount options, check if they are valid sids. 776 * also check if someone is trying to mount the same sb more 777 * than once with different security options. 778 */ 779 for (i = 0; i < num_opts; i++) { 780 u32 sid; 781 782 if (flags[i] == SBLABEL_MNT) 783 continue; 784 rc = security_context_str_to_sid(&selinux_state, 785 mount_options[i], &sid, 786 GFP_KERNEL); 787 if (rc) { 788 printk(KERN_WARNING "SELinux: security_context_str_to_sid" 789 "(%s) failed for (dev %s, type %s) errno=%d\n", 790 mount_options[i], sb->s_id, name, rc); 791 goto out; 792 } 793 switch (flags[i]) { 794 case FSCONTEXT_MNT: 795 fscontext_sid = sid; 796 797 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 798 fscontext_sid)) 799 goto out_double_mount; 800 801 sbsec->flags |= FSCONTEXT_MNT; 802 break; 803 case CONTEXT_MNT: 804 context_sid = sid; 805 806 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 807 context_sid)) 808 goto out_double_mount; 809 810 sbsec->flags |= CONTEXT_MNT; 811 break; 812 case ROOTCONTEXT_MNT: 813 rootcontext_sid = sid; 814 815 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 816 rootcontext_sid)) 817 goto out_double_mount; 818 819 sbsec->flags |= ROOTCONTEXT_MNT; 820 821 break; 822 case DEFCONTEXT_MNT: 823 defcontext_sid = sid; 824 825 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 826 defcontext_sid)) 827 goto out_double_mount; 828 829 sbsec->flags |= DEFCONTEXT_MNT; 830 831 break; 832 default: 833 rc = -EINVAL; 834 goto out; 835 } 836 } 837 838 if (sbsec->flags & SE_SBINITIALIZED) { 839 /* previously mounted with options, but not on this attempt? */ 840 if ((sbsec->flags & SE_MNTMASK) && !num_opts) 841 goto out_double_mount; 842 rc = 0; 843 goto out; 844 } 845 846 if (strcmp(sb->s_type->name, "proc") == 0) 847 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 848 849 if (!strcmp(sb->s_type->name, "debugfs") || 850 !strcmp(sb->s_type->name, "tracefs") || 851 !strcmp(sb->s_type->name, "sysfs") || 852 !strcmp(sb->s_type->name, "pstore") || 853 !strcmp(sb->s_type->name, "cgroup") || 854 !strcmp(sb->s_type->name, "cgroup2")) 855 sbsec->flags |= SE_SBGENFS; 856 857 if (!sbsec->behavior) { 858 /* 859 * Determine the labeling behavior to use for this 860 * filesystem type. 861 */ 862 rc = security_fs_use(&selinux_state, sb); 863 if (rc) { 864 printk(KERN_WARNING 865 "%s: security_fs_use(%s) returned %d\n", 866 __func__, sb->s_type->name, rc); 867 goto out; 868 } 869 } 870 871 /* 872 * If this is a user namespace mount and the filesystem type is not 873 * explicitly whitelisted, then no contexts are allowed on the command 874 * line and security labels must be ignored. 875 */ 876 if (sb->s_user_ns != &init_user_ns && 877 strcmp(sb->s_type->name, "tmpfs") && 878 strcmp(sb->s_type->name, "ramfs") && 879 strcmp(sb->s_type->name, "devpts")) { 880 if (context_sid || fscontext_sid || rootcontext_sid || 881 defcontext_sid) { 882 rc = -EACCES; 883 goto out; 884 } 885 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 886 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 887 rc = security_transition_sid(&selinux_state, 888 current_sid(), 889 current_sid(), 890 SECCLASS_FILE, NULL, 891 &sbsec->mntpoint_sid); 892 if (rc) 893 goto out; 894 } 895 goto out_set_opts; 896 } 897 898 /* sets the context of the superblock for the fs being mounted. */ 899 if (fscontext_sid) { 900 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 901 if (rc) 902 goto out; 903 904 sbsec->sid = fscontext_sid; 905 } 906 907 /* 908 * Switch to using mount point labeling behavior. 909 * sets the label used on all file below the mountpoint, and will set 910 * the superblock context if not already set. 911 */ 912 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 913 sbsec->behavior = SECURITY_FS_USE_NATIVE; 914 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 915 } 916 917 if (context_sid) { 918 if (!fscontext_sid) { 919 rc = may_context_mount_sb_relabel(context_sid, sbsec, 920 cred); 921 if (rc) 922 goto out; 923 sbsec->sid = context_sid; 924 } else { 925 rc = may_context_mount_inode_relabel(context_sid, sbsec, 926 cred); 927 if (rc) 928 goto out; 929 } 930 if (!rootcontext_sid) 931 rootcontext_sid = context_sid; 932 933 sbsec->mntpoint_sid = context_sid; 934 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 935 } 936 937 if (rootcontext_sid) { 938 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 939 cred); 940 if (rc) 941 goto out; 942 943 root_isec->sid = rootcontext_sid; 944 root_isec->initialized = LABEL_INITIALIZED; 945 } 946 947 if (defcontext_sid) { 948 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 949 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 950 rc = -EINVAL; 951 printk(KERN_WARNING "SELinux: defcontext option is " 952 "invalid for this filesystem type\n"); 953 goto out; 954 } 955 956 if (defcontext_sid != sbsec->def_sid) { 957 rc = may_context_mount_inode_relabel(defcontext_sid, 958 sbsec, cred); 959 if (rc) 960 goto out; 961 } 962 963 sbsec->def_sid = defcontext_sid; 964 } 965 966 out_set_opts: 967 rc = sb_finish_set_opts(sb); 968 out: 969 mutex_unlock(&sbsec->lock); 970 return rc; 971 out_double_mount: 972 rc = -EINVAL; 973 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 974 "security settings for (dev %s, type %s)\n", sb->s_id, name); 975 goto out; 976 } 977 978 static int selinux_cmp_sb_context(const struct super_block *oldsb, 979 const struct super_block *newsb) 980 { 981 struct superblock_security_struct *old = oldsb->s_security; 982 struct superblock_security_struct *new = newsb->s_security; 983 char oldflags = old->flags & SE_MNTMASK; 984 char newflags = new->flags & SE_MNTMASK; 985 986 if (oldflags != newflags) 987 goto mismatch; 988 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 989 goto mismatch; 990 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 991 goto mismatch; 992 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 993 goto mismatch; 994 if (oldflags & ROOTCONTEXT_MNT) { 995 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 996 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 997 if (oldroot->sid != newroot->sid) 998 goto mismatch; 999 } 1000 return 0; 1001 mismatch: 1002 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " 1003 "different security settings for (dev %s, " 1004 "type %s)\n", newsb->s_id, newsb->s_type->name); 1005 return -EBUSY; 1006 } 1007 1008 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 1009 struct super_block *newsb, 1010 unsigned long kern_flags, 1011 unsigned long *set_kern_flags) 1012 { 1013 int rc = 0; 1014 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 1015 struct superblock_security_struct *newsbsec = newsb->s_security; 1016 1017 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 1018 int set_context = (oldsbsec->flags & CONTEXT_MNT); 1019 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 1020 1021 /* 1022 * if the parent was able to be mounted it clearly had no special lsm 1023 * mount options. thus we can safely deal with this superblock later 1024 */ 1025 if (!selinux_state.initialized) 1026 return 0; 1027 1028 /* 1029 * Specifying internal flags without providing a place to 1030 * place the results is not allowed. 1031 */ 1032 if (kern_flags && !set_kern_flags) 1033 return -EINVAL; 1034 1035 /* how can we clone if the old one wasn't set up?? */ 1036 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 1037 1038 /* if fs is reusing a sb, make sure that the contexts match */ 1039 if (newsbsec->flags & SE_SBINITIALIZED) 1040 return selinux_cmp_sb_context(oldsb, newsb); 1041 1042 mutex_lock(&newsbsec->lock); 1043 1044 newsbsec->flags = oldsbsec->flags; 1045 1046 newsbsec->sid = oldsbsec->sid; 1047 newsbsec->def_sid = oldsbsec->def_sid; 1048 newsbsec->behavior = oldsbsec->behavior; 1049 1050 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && 1051 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { 1052 rc = security_fs_use(&selinux_state, newsb); 1053 if (rc) 1054 goto out; 1055 } 1056 1057 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { 1058 newsbsec->behavior = SECURITY_FS_USE_NATIVE; 1059 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 1060 } 1061 1062 if (set_context) { 1063 u32 sid = oldsbsec->mntpoint_sid; 1064 1065 if (!set_fscontext) 1066 newsbsec->sid = sid; 1067 if (!set_rootcontext) { 1068 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 1069 newisec->sid = sid; 1070 } 1071 newsbsec->mntpoint_sid = sid; 1072 } 1073 if (set_rootcontext) { 1074 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 1075 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 1076 1077 newisec->sid = oldisec->sid; 1078 } 1079 1080 sb_finish_set_opts(newsb); 1081 out: 1082 mutex_unlock(&newsbsec->lock); 1083 return rc; 1084 } 1085 1086 static int selinux_parse_opts_str(char *options, 1087 struct security_mnt_opts *opts) 1088 { 1089 char *p; 1090 char *context = NULL, *defcontext = NULL; 1091 char *fscontext = NULL, *rootcontext = NULL; 1092 int rc, num_mnt_opts = 0; 1093 1094 opts->num_mnt_opts = 0; 1095 1096 /* Standard string-based options. */ 1097 while ((p = strsep(&options, "|")) != NULL) { 1098 int token; 1099 substring_t args[MAX_OPT_ARGS]; 1100 1101 if (!*p) 1102 continue; 1103 1104 token = match_token(p, tokens, args); 1105 1106 switch (token) { 1107 case Opt_context: 1108 if (context || defcontext) { 1109 rc = -EINVAL; 1110 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1111 goto out_err; 1112 } 1113 context = match_strdup(&args[0]); 1114 if (!context) { 1115 rc = -ENOMEM; 1116 goto out_err; 1117 } 1118 break; 1119 1120 case Opt_fscontext: 1121 if (fscontext) { 1122 rc = -EINVAL; 1123 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1124 goto out_err; 1125 } 1126 fscontext = match_strdup(&args[0]); 1127 if (!fscontext) { 1128 rc = -ENOMEM; 1129 goto out_err; 1130 } 1131 break; 1132 1133 case Opt_rootcontext: 1134 if (rootcontext) { 1135 rc = -EINVAL; 1136 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1137 goto out_err; 1138 } 1139 rootcontext = match_strdup(&args[0]); 1140 if (!rootcontext) { 1141 rc = -ENOMEM; 1142 goto out_err; 1143 } 1144 break; 1145 1146 case Opt_defcontext: 1147 if (context || defcontext) { 1148 rc = -EINVAL; 1149 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1150 goto out_err; 1151 } 1152 defcontext = match_strdup(&args[0]); 1153 if (!defcontext) { 1154 rc = -ENOMEM; 1155 goto out_err; 1156 } 1157 break; 1158 case Opt_labelsupport: 1159 break; 1160 default: 1161 rc = -EINVAL; 1162 printk(KERN_WARNING "SELinux: unknown mount option\n"); 1163 goto out_err; 1164 1165 } 1166 } 1167 1168 rc = -ENOMEM; 1169 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL); 1170 if (!opts->mnt_opts) 1171 goto out_err; 1172 1173 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), 1174 GFP_KERNEL); 1175 if (!opts->mnt_opts_flags) 1176 goto out_err; 1177 1178 if (fscontext) { 1179 opts->mnt_opts[num_mnt_opts] = fscontext; 1180 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 1181 } 1182 if (context) { 1183 opts->mnt_opts[num_mnt_opts] = context; 1184 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 1185 } 1186 if (rootcontext) { 1187 opts->mnt_opts[num_mnt_opts] = rootcontext; 1188 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 1189 } 1190 if (defcontext) { 1191 opts->mnt_opts[num_mnt_opts] = defcontext; 1192 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 1193 } 1194 1195 opts->num_mnt_opts = num_mnt_opts; 1196 return 0; 1197 1198 out_err: 1199 security_free_mnt_opts(opts); 1200 kfree(context); 1201 kfree(defcontext); 1202 kfree(fscontext); 1203 kfree(rootcontext); 1204 return rc; 1205 } 1206 /* 1207 * string mount options parsing and call set the sbsec 1208 */ 1209 static int superblock_doinit(struct super_block *sb, void *data) 1210 { 1211 int rc = 0; 1212 char *options = data; 1213 struct security_mnt_opts opts; 1214 1215 security_init_mnt_opts(&opts); 1216 1217 if (!data) 1218 goto out; 1219 1220 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 1221 1222 rc = selinux_parse_opts_str(options, &opts); 1223 if (rc) 1224 goto out_err; 1225 1226 out: 1227 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); 1228 1229 out_err: 1230 security_free_mnt_opts(&opts); 1231 return rc; 1232 } 1233 1234 static void selinux_write_opts(struct seq_file *m, 1235 struct security_mnt_opts *opts) 1236 { 1237 int i; 1238 char *prefix; 1239 1240 for (i = 0; i < opts->num_mnt_opts; i++) { 1241 char *has_comma; 1242 1243 if (opts->mnt_opts[i]) 1244 has_comma = strchr(opts->mnt_opts[i], ','); 1245 else 1246 has_comma = NULL; 1247 1248 switch (opts->mnt_opts_flags[i]) { 1249 case CONTEXT_MNT: 1250 prefix = CONTEXT_STR; 1251 break; 1252 case FSCONTEXT_MNT: 1253 prefix = FSCONTEXT_STR; 1254 break; 1255 case ROOTCONTEXT_MNT: 1256 prefix = ROOTCONTEXT_STR; 1257 break; 1258 case DEFCONTEXT_MNT: 1259 prefix = DEFCONTEXT_STR; 1260 break; 1261 case SBLABEL_MNT: 1262 seq_putc(m, ','); 1263 seq_puts(m, LABELSUPP_STR); 1264 continue; 1265 default: 1266 BUG(); 1267 return; 1268 }; 1269 /* we need a comma before each option */ 1270 seq_putc(m, ','); 1271 seq_puts(m, prefix); 1272 if (has_comma) 1273 seq_putc(m, '\"'); 1274 seq_escape(m, opts->mnt_opts[i], "\"\n\\"); 1275 if (has_comma) 1276 seq_putc(m, '\"'); 1277 } 1278 } 1279 1280 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1281 { 1282 struct security_mnt_opts opts; 1283 int rc; 1284 1285 rc = selinux_get_mnt_opts(sb, &opts); 1286 if (rc) { 1287 /* before policy load we may get EINVAL, don't show anything */ 1288 if (rc == -EINVAL) 1289 rc = 0; 1290 return rc; 1291 } 1292 1293 selinux_write_opts(m, &opts); 1294 1295 security_free_mnt_opts(&opts); 1296 1297 return rc; 1298 } 1299 1300 static inline u16 inode_mode_to_security_class(umode_t mode) 1301 { 1302 switch (mode & S_IFMT) { 1303 case S_IFSOCK: 1304 return SECCLASS_SOCK_FILE; 1305 case S_IFLNK: 1306 return SECCLASS_LNK_FILE; 1307 case S_IFREG: 1308 return SECCLASS_FILE; 1309 case S_IFBLK: 1310 return SECCLASS_BLK_FILE; 1311 case S_IFDIR: 1312 return SECCLASS_DIR; 1313 case S_IFCHR: 1314 return SECCLASS_CHR_FILE; 1315 case S_IFIFO: 1316 return SECCLASS_FIFO_FILE; 1317 1318 } 1319 1320 return SECCLASS_FILE; 1321 } 1322 1323 static inline int default_protocol_stream(int protocol) 1324 { 1325 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1326 } 1327 1328 static inline int default_protocol_dgram(int protocol) 1329 { 1330 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1331 } 1332 1333 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1334 { 1335 int extsockclass = selinux_policycap_extsockclass(); 1336 1337 switch (family) { 1338 case PF_UNIX: 1339 switch (type) { 1340 case SOCK_STREAM: 1341 case SOCK_SEQPACKET: 1342 return SECCLASS_UNIX_STREAM_SOCKET; 1343 case SOCK_DGRAM: 1344 case SOCK_RAW: 1345 return SECCLASS_UNIX_DGRAM_SOCKET; 1346 } 1347 break; 1348 case PF_INET: 1349 case PF_INET6: 1350 switch (type) { 1351 case SOCK_STREAM: 1352 case SOCK_SEQPACKET: 1353 if (default_protocol_stream(protocol)) 1354 return SECCLASS_TCP_SOCKET; 1355 else if (extsockclass && protocol == IPPROTO_SCTP) 1356 return SECCLASS_SCTP_SOCKET; 1357 else 1358 return SECCLASS_RAWIP_SOCKET; 1359 case SOCK_DGRAM: 1360 if (default_protocol_dgram(protocol)) 1361 return SECCLASS_UDP_SOCKET; 1362 else if (extsockclass && (protocol == IPPROTO_ICMP || 1363 protocol == IPPROTO_ICMPV6)) 1364 return SECCLASS_ICMP_SOCKET; 1365 else 1366 return SECCLASS_RAWIP_SOCKET; 1367 case SOCK_DCCP: 1368 return SECCLASS_DCCP_SOCKET; 1369 default: 1370 return SECCLASS_RAWIP_SOCKET; 1371 } 1372 break; 1373 case PF_NETLINK: 1374 switch (protocol) { 1375 case NETLINK_ROUTE: 1376 return SECCLASS_NETLINK_ROUTE_SOCKET; 1377 case NETLINK_SOCK_DIAG: 1378 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1379 case NETLINK_NFLOG: 1380 return SECCLASS_NETLINK_NFLOG_SOCKET; 1381 case NETLINK_XFRM: 1382 return SECCLASS_NETLINK_XFRM_SOCKET; 1383 case NETLINK_SELINUX: 1384 return SECCLASS_NETLINK_SELINUX_SOCKET; 1385 case NETLINK_ISCSI: 1386 return SECCLASS_NETLINK_ISCSI_SOCKET; 1387 case NETLINK_AUDIT: 1388 return SECCLASS_NETLINK_AUDIT_SOCKET; 1389 case NETLINK_FIB_LOOKUP: 1390 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1391 case NETLINK_CONNECTOR: 1392 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1393 case NETLINK_NETFILTER: 1394 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1395 case NETLINK_DNRTMSG: 1396 return SECCLASS_NETLINK_DNRT_SOCKET; 1397 case NETLINK_KOBJECT_UEVENT: 1398 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1399 case NETLINK_GENERIC: 1400 return SECCLASS_NETLINK_GENERIC_SOCKET; 1401 case NETLINK_SCSITRANSPORT: 1402 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1403 case NETLINK_RDMA: 1404 return SECCLASS_NETLINK_RDMA_SOCKET; 1405 case NETLINK_CRYPTO: 1406 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1407 default: 1408 return SECCLASS_NETLINK_SOCKET; 1409 } 1410 case PF_PACKET: 1411 return SECCLASS_PACKET_SOCKET; 1412 case PF_KEY: 1413 return SECCLASS_KEY_SOCKET; 1414 case PF_APPLETALK: 1415 return SECCLASS_APPLETALK_SOCKET; 1416 } 1417 1418 if (extsockclass) { 1419 switch (family) { 1420 case PF_AX25: 1421 return SECCLASS_AX25_SOCKET; 1422 case PF_IPX: 1423 return SECCLASS_IPX_SOCKET; 1424 case PF_NETROM: 1425 return SECCLASS_NETROM_SOCKET; 1426 case PF_ATMPVC: 1427 return SECCLASS_ATMPVC_SOCKET; 1428 case PF_X25: 1429 return SECCLASS_X25_SOCKET; 1430 case PF_ROSE: 1431 return SECCLASS_ROSE_SOCKET; 1432 case PF_DECnet: 1433 return SECCLASS_DECNET_SOCKET; 1434 case PF_ATMSVC: 1435 return SECCLASS_ATMSVC_SOCKET; 1436 case PF_RDS: 1437 return SECCLASS_RDS_SOCKET; 1438 case PF_IRDA: 1439 return SECCLASS_IRDA_SOCKET; 1440 case PF_PPPOX: 1441 return SECCLASS_PPPOX_SOCKET; 1442 case PF_LLC: 1443 return SECCLASS_LLC_SOCKET; 1444 case PF_CAN: 1445 return SECCLASS_CAN_SOCKET; 1446 case PF_TIPC: 1447 return SECCLASS_TIPC_SOCKET; 1448 case PF_BLUETOOTH: 1449 return SECCLASS_BLUETOOTH_SOCKET; 1450 case PF_IUCV: 1451 return SECCLASS_IUCV_SOCKET; 1452 case PF_RXRPC: 1453 return SECCLASS_RXRPC_SOCKET; 1454 case PF_ISDN: 1455 return SECCLASS_ISDN_SOCKET; 1456 case PF_PHONET: 1457 return SECCLASS_PHONET_SOCKET; 1458 case PF_IEEE802154: 1459 return SECCLASS_IEEE802154_SOCKET; 1460 case PF_CAIF: 1461 return SECCLASS_CAIF_SOCKET; 1462 case PF_ALG: 1463 return SECCLASS_ALG_SOCKET; 1464 case PF_NFC: 1465 return SECCLASS_NFC_SOCKET; 1466 case PF_VSOCK: 1467 return SECCLASS_VSOCK_SOCKET; 1468 case PF_KCM: 1469 return SECCLASS_KCM_SOCKET; 1470 case PF_QIPCRTR: 1471 return SECCLASS_QIPCRTR_SOCKET; 1472 case PF_SMC: 1473 return SECCLASS_SMC_SOCKET; 1474 #if PF_MAX > 44 1475 #error New address family defined, please update this function. 1476 #endif 1477 } 1478 } 1479 1480 return SECCLASS_SOCKET; 1481 } 1482 1483 static int selinux_genfs_get_sid(struct dentry *dentry, 1484 u16 tclass, 1485 u16 flags, 1486 u32 *sid) 1487 { 1488 int rc; 1489 struct super_block *sb = dentry->d_sb; 1490 char *buffer, *path; 1491 1492 buffer = (char *)__get_free_page(GFP_KERNEL); 1493 if (!buffer) 1494 return -ENOMEM; 1495 1496 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1497 if (IS_ERR(path)) 1498 rc = PTR_ERR(path); 1499 else { 1500 if (flags & SE_SBPROC) { 1501 /* each process gets a /proc/PID/ entry. Strip off the 1502 * PID part to get a valid selinux labeling. 1503 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1504 while (path[1] >= '0' && path[1] <= '9') { 1505 path[1] = '/'; 1506 path++; 1507 } 1508 } 1509 rc = security_genfs_sid(&selinux_state, sb->s_type->name, 1510 path, tclass, sid); 1511 } 1512 free_page((unsigned long)buffer); 1513 return rc; 1514 } 1515 1516 /* The inode's security attributes must be initialized before first use. */ 1517 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1518 { 1519 struct superblock_security_struct *sbsec = NULL; 1520 struct inode_security_struct *isec = inode->i_security; 1521 u32 task_sid, sid = 0; 1522 u16 sclass; 1523 struct dentry *dentry; 1524 #define INITCONTEXTLEN 255 1525 char *context = NULL; 1526 unsigned len = 0; 1527 int rc = 0; 1528 1529 if (isec->initialized == LABEL_INITIALIZED) 1530 return 0; 1531 1532 spin_lock(&isec->lock); 1533 if (isec->initialized == LABEL_INITIALIZED) 1534 goto out_unlock; 1535 1536 if (isec->sclass == SECCLASS_FILE) 1537 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1538 1539 sbsec = inode->i_sb->s_security; 1540 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1541 /* Defer initialization until selinux_complete_init, 1542 after the initial policy is loaded and the security 1543 server is ready to handle calls. */ 1544 spin_lock(&sbsec->isec_lock); 1545 if (list_empty(&isec->list)) 1546 list_add(&isec->list, &sbsec->isec_head); 1547 spin_unlock(&sbsec->isec_lock); 1548 goto out_unlock; 1549 } 1550 1551 sclass = isec->sclass; 1552 task_sid = isec->task_sid; 1553 sid = isec->sid; 1554 isec->initialized = LABEL_PENDING; 1555 spin_unlock(&isec->lock); 1556 1557 switch (sbsec->behavior) { 1558 case SECURITY_FS_USE_NATIVE: 1559 break; 1560 case SECURITY_FS_USE_XATTR: 1561 if (!(inode->i_opflags & IOP_XATTR)) { 1562 sid = sbsec->def_sid; 1563 break; 1564 } 1565 /* Need a dentry, since the xattr API requires one. 1566 Life would be simpler if we could just pass the inode. */ 1567 if (opt_dentry) { 1568 /* Called from d_instantiate or d_splice_alias. */ 1569 dentry = dget(opt_dentry); 1570 } else { 1571 /* Called from selinux_complete_init, try to find a dentry. */ 1572 dentry = d_find_alias(inode); 1573 } 1574 if (!dentry) { 1575 /* 1576 * this is can be hit on boot when a file is accessed 1577 * before the policy is loaded. When we load policy we 1578 * may find inodes that have no dentry on the 1579 * sbsec->isec_head list. No reason to complain as these 1580 * will get fixed up the next time we go through 1581 * inode_doinit with a dentry, before these inodes could 1582 * be used again by userspace. 1583 */ 1584 goto out; 1585 } 1586 1587 len = INITCONTEXTLEN; 1588 context = kmalloc(len+1, GFP_NOFS); 1589 if (!context) { 1590 rc = -ENOMEM; 1591 dput(dentry); 1592 goto out; 1593 } 1594 context[len] = '\0'; 1595 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1596 if (rc == -ERANGE) { 1597 kfree(context); 1598 1599 /* Need a larger buffer. Query for the right size. */ 1600 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1601 if (rc < 0) { 1602 dput(dentry); 1603 goto out; 1604 } 1605 len = rc; 1606 context = kmalloc(len+1, GFP_NOFS); 1607 if (!context) { 1608 rc = -ENOMEM; 1609 dput(dentry); 1610 goto out; 1611 } 1612 context[len] = '\0'; 1613 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1614 } 1615 dput(dentry); 1616 if (rc < 0) { 1617 if (rc != -ENODATA) { 1618 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1619 "%d for dev=%s ino=%ld\n", __func__, 1620 -rc, inode->i_sb->s_id, inode->i_ino); 1621 kfree(context); 1622 goto out; 1623 } 1624 /* Map ENODATA to the default file SID */ 1625 sid = sbsec->def_sid; 1626 rc = 0; 1627 } else { 1628 rc = security_context_to_sid_default(&selinux_state, 1629 context, rc, &sid, 1630 sbsec->def_sid, 1631 GFP_NOFS); 1632 if (rc) { 1633 char *dev = inode->i_sb->s_id; 1634 unsigned long ino = inode->i_ino; 1635 1636 if (rc == -EINVAL) { 1637 if (printk_ratelimit()) 1638 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1639 "context=%s. This indicates you may need to relabel the inode or the " 1640 "filesystem in question.\n", ino, dev, context); 1641 } else { 1642 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1643 "returned %d for dev=%s ino=%ld\n", 1644 __func__, context, -rc, dev, ino); 1645 } 1646 kfree(context); 1647 /* Leave with the unlabeled SID */ 1648 rc = 0; 1649 break; 1650 } 1651 } 1652 kfree(context); 1653 break; 1654 case SECURITY_FS_USE_TASK: 1655 sid = task_sid; 1656 break; 1657 case SECURITY_FS_USE_TRANS: 1658 /* Default to the fs SID. */ 1659 sid = sbsec->sid; 1660 1661 /* Try to obtain a transition SID. */ 1662 rc = security_transition_sid(&selinux_state, task_sid, sid, 1663 sclass, NULL, &sid); 1664 if (rc) 1665 goto out; 1666 break; 1667 case SECURITY_FS_USE_MNTPOINT: 1668 sid = sbsec->mntpoint_sid; 1669 break; 1670 default: 1671 /* Default to the fs superblock SID. */ 1672 sid = sbsec->sid; 1673 1674 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { 1675 /* We must have a dentry to determine the label on 1676 * procfs inodes */ 1677 if (opt_dentry) 1678 /* Called from d_instantiate or 1679 * d_splice_alias. */ 1680 dentry = dget(opt_dentry); 1681 else 1682 /* Called from selinux_complete_init, try to 1683 * find a dentry. */ 1684 dentry = d_find_alias(inode); 1685 /* 1686 * This can be hit on boot when a file is accessed 1687 * before the policy is loaded. When we load policy we 1688 * may find inodes that have no dentry on the 1689 * sbsec->isec_head list. No reason to complain as 1690 * these will get fixed up the next time we go through 1691 * inode_doinit() with a dentry, before these inodes 1692 * could be used again by userspace. 1693 */ 1694 if (!dentry) 1695 goto out; 1696 rc = selinux_genfs_get_sid(dentry, sclass, 1697 sbsec->flags, &sid); 1698 dput(dentry); 1699 if (rc) 1700 goto out; 1701 } 1702 break; 1703 } 1704 1705 out: 1706 spin_lock(&isec->lock); 1707 if (isec->initialized == LABEL_PENDING) { 1708 if (!sid || rc) { 1709 isec->initialized = LABEL_INVALID; 1710 goto out_unlock; 1711 } 1712 1713 isec->initialized = LABEL_INITIALIZED; 1714 isec->sid = sid; 1715 } 1716 1717 out_unlock: 1718 spin_unlock(&isec->lock); 1719 return rc; 1720 } 1721 1722 /* Convert a Linux signal to an access vector. */ 1723 static inline u32 signal_to_av(int sig) 1724 { 1725 u32 perm = 0; 1726 1727 switch (sig) { 1728 case SIGCHLD: 1729 /* Commonly granted from child to parent. */ 1730 perm = PROCESS__SIGCHLD; 1731 break; 1732 case SIGKILL: 1733 /* Cannot be caught or ignored */ 1734 perm = PROCESS__SIGKILL; 1735 break; 1736 case SIGSTOP: 1737 /* Cannot be caught or ignored */ 1738 perm = PROCESS__SIGSTOP; 1739 break; 1740 default: 1741 /* All other signals. */ 1742 perm = PROCESS__SIGNAL; 1743 break; 1744 } 1745 1746 return perm; 1747 } 1748 1749 #if CAP_LAST_CAP > 63 1750 #error Fix SELinux to handle capabilities > 63. 1751 #endif 1752 1753 /* Check whether a task is allowed to use a capability. */ 1754 static int cred_has_capability(const struct cred *cred, 1755 int cap, int audit, bool initns) 1756 { 1757 struct common_audit_data ad; 1758 struct av_decision avd; 1759 u16 sclass; 1760 u32 sid = cred_sid(cred); 1761 u32 av = CAP_TO_MASK(cap); 1762 int rc; 1763 1764 ad.type = LSM_AUDIT_DATA_CAP; 1765 ad.u.cap = cap; 1766 1767 switch (CAP_TO_INDEX(cap)) { 1768 case 0: 1769 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1770 break; 1771 case 1: 1772 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1773 break; 1774 default: 1775 printk(KERN_ERR 1776 "SELinux: out of range capability %d\n", cap); 1777 BUG(); 1778 return -EINVAL; 1779 } 1780 1781 rc = avc_has_perm_noaudit(&selinux_state, 1782 sid, sid, sclass, av, 0, &avd); 1783 if (audit == SECURITY_CAP_AUDIT) { 1784 int rc2 = avc_audit(&selinux_state, 1785 sid, sid, sclass, av, &avd, rc, &ad, 0); 1786 if (rc2) 1787 return rc2; 1788 } 1789 return rc; 1790 } 1791 1792 /* Check whether a task has a particular permission to an inode. 1793 The 'adp' parameter is optional and allows other audit 1794 data to be passed (e.g. the dentry). */ 1795 static int inode_has_perm(const struct cred *cred, 1796 struct inode *inode, 1797 u32 perms, 1798 struct common_audit_data *adp) 1799 { 1800 struct inode_security_struct *isec; 1801 u32 sid; 1802 1803 validate_creds(cred); 1804 1805 if (unlikely(IS_PRIVATE(inode))) 1806 return 0; 1807 1808 sid = cred_sid(cred); 1809 isec = inode->i_security; 1810 1811 return avc_has_perm(&selinux_state, 1812 sid, isec->sid, isec->sclass, perms, adp); 1813 } 1814 1815 /* Same as inode_has_perm, but pass explicit audit data containing 1816 the dentry to help the auditing code to more easily generate the 1817 pathname if needed. */ 1818 static inline int dentry_has_perm(const struct cred *cred, 1819 struct dentry *dentry, 1820 u32 av) 1821 { 1822 struct inode *inode = d_backing_inode(dentry); 1823 struct common_audit_data ad; 1824 1825 ad.type = LSM_AUDIT_DATA_DENTRY; 1826 ad.u.dentry = dentry; 1827 __inode_security_revalidate(inode, dentry, true); 1828 return inode_has_perm(cred, inode, av, &ad); 1829 } 1830 1831 /* Same as inode_has_perm, but pass explicit audit data containing 1832 the path to help the auditing code to more easily generate the 1833 pathname if needed. */ 1834 static inline int path_has_perm(const struct cred *cred, 1835 const struct path *path, 1836 u32 av) 1837 { 1838 struct inode *inode = d_backing_inode(path->dentry); 1839 struct common_audit_data ad; 1840 1841 ad.type = LSM_AUDIT_DATA_PATH; 1842 ad.u.path = *path; 1843 __inode_security_revalidate(inode, path->dentry, true); 1844 return inode_has_perm(cred, inode, av, &ad); 1845 } 1846 1847 /* Same as path_has_perm, but uses the inode from the file struct. */ 1848 static inline int file_path_has_perm(const struct cred *cred, 1849 struct file *file, 1850 u32 av) 1851 { 1852 struct common_audit_data ad; 1853 1854 ad.type = LSM_AUDIT_DATA_FILE; 1855 ad.u.file = file; 1856 return inode_has_perm(cred, file_inode(file), av, &ad); 1857 } 1858 1859 #ifdef CONFIG_BPF_SYSCALL 1860 static int bpf_fd_pass(struct file *file, u32 sid); 1861 #endif 1862 1863 /* Check whether a task can use an open file descriptor to 1864 access an inode in a given way. Check access to the 1865 descriptor itself, and then use dentry_has_perm to 1866 check a particular permission to the file. 1867 Access to the descriptor is implicitly granted if it 1868 has the same SID as the process. If av is zero, then 1869 access to the file is not checked, e.g. for cases 1870 where only the descriptor is affected like seek. */ 1871 static int file_has_perm(const struct cred *cred, 1872 struct file *file, 1873 u32 av) 1874 { 1875 struct file_security_struct *fsec = file->f_security; 1876 struct inode *inode = file_inode(file); 1877 struct common_audit_data ad; 1878 u32 sid = cred_sid(cred); 1879 int rc; 1880 1881 ad.type = LSM_AUDIT_DATA_FILE; 1882 ad.u.file = file; 1883 1884 if (sid != fsec->sid) { 1885 rc = avc_has_perm(&selinux_state, 1886 sid, fsec->sid, 1887 SECCLASS_FD, 1888 FD__USE, 1889 &ad); 1890 if (rc) 1891 goto out; 1892 } 1893 1894 #ifdef CONFIG_BPF_SYSCALL 1895 rc = bpf_fd_pass(file, cred_sid(cred)); 1896 if (rc) 1897 return rc; 1898 #endif 1899 1900 /* av is zero if only checking access to the descriptor. */ 1901 rc = 0; 1902 if (av) 1903 rc = inode_has_perm(cred, inode, av, &ad); 1904 1905 out: 1906 return rc; 1907 } 1908 1909 /* 1910 * Determine the label for an inode that might be unioned. 1911 */ 1912 static int 1913 selinux_determine_inode_label(const struct task_security_struct *tsec, 1914 struct inode *dir, 1915 const struct qstr *name, u16 tclass, 1916 u32 *_new_isid) 1917 { 1918 const struct superblock_security_struct *sbsec = dir->i_sb->s_security; 1919 1920 if ((sbsec->flags & SE_SBINITIALIZED) && 1921 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1922 *_new_isid = sbsec->mntpoint_sid; 1923 } else if ((sbsec->flags & SBLABEL_MNT) && 1924 tsec->create_sid) { 1925 *_new_isid = tsec->create_sid; 1926 } else { 1927 const struct inode_security_struct *dsec = inode_security(dir); 1928 return security_transition_sid(&selinux_state, tsec->sid, 1929 dsec->sid, tclass, 1930 name, _new_isid); 1931 } 1932 1933 return 0; 1934 } 1935 1936 /* Check whether a task can create a file. */ 1937 static int may_create(struct inode *dir, 1938 struct dentry *dentry, 1939 u16 tclass) 1940 { 1941 const struct task_security_struct *tsec = current_security(); 1942 struct inode_security_struct *dsec; 1943 struct superblock_security_struct *sbsec; 1944 u32 sid, newsid; 1945 struct common_audit_data ad; 1946 int rc; 1947 1948 dsec = inode_security(dir); 1949 sbsec = dir->i_sb->s_security; 1950 1951 sid = tsec->sid; 1952 1953 ad.type = LSM_AUDIT_DATA_DENTRY; 1954 ad.u.dentry = dentry; 1955 1956 rc = avc_has_perm(&selinux_state, 1957 sid, dsec->sid, SECCLASS_DIR, 1958 DIR__ADD_NAME | DIR__SEARCH, 1959 &ad); 1960 if (rc) 1961 return rc; 1962 1963 rc = selinux_determine_inode_label(current_security(), dir, 1964 &dentry->d_name, tclass, &newsid); 1965 if (rc) 1966 return rc; 1967 1968 rc = avc_has_perm(&selinux_state, 1969 sid, newsid, tclass, FILE__CREATE, &ad); 1970 if (rc) 1971 return rc; 1972 1973 return avc_has_perm(&selinux_state, 1974 newsid, sbsec->sid, 1975 SECCLASS_FILESYSTEM, 1976 FILESYSTEM__ASSOCIATE, &ad); 1977 } 1978 1979 #define MAY_LINK 0 1980 #define MAY_UNLINK 1 1981 #define MAY_RMDIR 2 1982 1983 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1984 static int may_link(struct inode *dir, 1985 struct dentry *dentry, 1986 int kind) 1987 1988 { 1989 struct inode_security_struct *dsec, *isec; 1990 struct common_audit_data ad; 1991 u32 sid = current_sid(); 1992 u32 av; 1993 int rc; 1994 1995 dsec = inode_security(dir); 1996 isec = backing_inode_security(dentry); 1997 1998 ad.type = LSM_AUDIT_DATA_DENTRY; 1999 ad.u.dentry = dentry; 2000 2001 av = DIR__SEARCH; 2002 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 2003 rc = avc_has_perm(&selinux_state, 2004 sid, dsec->sid, SECCLASS_DIR, av, &ad); 2005 if (rc) 2006 return rc; 2007 2008 switch (kind) { 2009 case MAY_LINK: 2010 av = FILE__LINK; 2011 break; 2012 case MAY_UNLINK: 2013 av = FILE__UNLINK; 2014 break; 2015 case MAY_RMDIR: 2016 av = DIR__RMDIR; 2017 break; 2018 default: 2019 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 2020 __func__, kind); 2021 return 0; 2022 } 2023 2024 rc = avc_has_perm(&selinux_state, 2025 sid, isec->sid, isec->sclass, av, &ad); 2026 return rc; 2027 } 2028 2029 static inline int may_rename(struct inode *old_dir, 2030 struct dentry *old_dentry, 2031 struct inode *new_dir, 2032 struct dentry *new_dentry) 2033 { 2034 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 2035 struct common_audit_data ad; 2036 u32 sid = current_sid(); 2037 u32 av; 2038 int old_is_dir, new_is_dir; 2039 int rc; 2040 2041 old_dsec = inode_security(old_dir); 2042 old_isec = backing_inode_security(old_dentry); 2043 old_is_dir = d_is_dir(old_dentry); 2044 new_dsec = inode_security(new_dir); 2045 2046 ad.type = LSM_AUDIT_DATA_DENTRY; 2047 2048 ad.u.dentry = old_dentry; 2049 rc = avc_has_perm(&selinux_state, 2050 sid, old_dsec->sid, SECCLASS_DIR, 2051 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 2052 if (rc) 2053 return rc; 2054 rc = avc_has_perm(&selinux_state, 2055 sid, old_isec->sid, 2056 old_isec->sclass, FILE__RENAME, &ad); 2057 if (rc) 2058 return rc; 2059 if (old_is_dir && new_dir != old_dir) { 2060 rc = avc_has_perm(&selinux_state, 2061 sid, old_isec->sid, 2062 old_isec->sclass, DIR__REPARENT, &ad); 2063 if (rc) 2064 return rc; 2065 } 2066 2067 ad.u.dentry = new_dentry; 2068 av = DIR__ADD_NAME | DIR__SEARCH; 2069 if (d_is_positive(new_dentry)) 2070 av |= DIR__REMOVE_NAME; 2071 rc = avc_has_perm(&selinux_state, 2072 sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 2073 if (rc) 2074 return rc; 2075 if (d_is_positive(new_dentry)) { 2076 new_isec = backing_inode_security(new_dentry); 2077 new_is_dir = d_is_dir(new_dentry); 2078 rc = avc_has_perm(&selinux_state, 2079 sid, new_isec->sid, 2080 new_isec->sclass, 2081 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 2082 if (rc) 2083 return rc; 2084 } 2085 2086 return 0; 2087 } 2088 2089 /* Check whether a task can perform a filesystem operation. */ 2090 static int superblock_has_perm(const struct cred *cred, 2091 struct super_block *sb, 2092 u32 perms, 2093 struct common_audit_data *ad) 2094 { 2095 struct superblock_security_struct *sbsec; 2096 u32 sid = cred_sid(cred); 2097 2098 sbsec = sb->s_security; 2099 return avc_has_perm(&selinux_state, 2100 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 2101 } 2102 2103 /* Convert a Linux mode and permission mask to an access vector. */ 2104 static inline u32 file_mask_to_av(int mode, int mask) 2105 { 2106 u32 av = 0; 2107 2108 if (!S_ISDIR(mode)) { 2109 if (mask & MAY_EXEC) 2110 av |= FILE__EXECUTE; 2111 if (mask & MAY_READ) 2112 av |= FILE__READ; 2113 2114 if (mask & MAY_APPEND) 2115 av |= FILE__APPEND; 2116 else if (mask & MAY_WRITE) 2117 av |= FILE__WRITE; 2118 2119 } else { 2120 if (mask & MAY_EXEC) 2121 av |= DIR__SEARCH; 2122 if (mask & MAY_WRITE) 2123 av |= DIR__WRITE; 2124 if (mask & MAY_READ) 2125 av |= DIR__READ; 2126 } 2127 2128 return av; 2129 } 2130 2131 /* Convert a Linux file to an access vector. */ 2132 static inline u32 file_to_av(struct file *file) 2133 { 2134 u32 av = 0; 2135 2136 if (file->f_mode & FMODE_READ) 2137 av |= FILE__READ; 2138 if (file->f_mode & FMODE_WRITE) { 2139 if (file->f_flags & O_APPEND) 2140 av |= FILE__APPEND; 2141 else 2142 av |= FILE__WRITE; 2143 } 2144 if (!av) { 2145 /* 2146 * Special file opened with flags 3 for ioctl-only use. 2147 */ 2148 av = FILE__IOCTL; 2149 } 2150 2151 return av; 2152 } 2153 2154 /* 2155 * Convert a file to an access vector and include the correct open 2156 * open permission. 2157 */ 2158 static inline u32 open_file_to_av(struct file *file) 2159 { 2160 u32 av = file_to_av(file); 2161 struct inode *inode = file_inode(file); 2162 2163 if (selinux_policycap_openperm() && 2164 inode->i_sb->s_magic != SOCKFS_MAGIC) 2165 av |= FILE__OPEN; 2166 2167 return av; 2168 } 2169 2170 /* Hook functions begin here. */ 2171 2172 static int selinux_binder_set_context_mgr(struct task_struct *mgr) 2173 { 2174 u32 mysid = current_sid(); 2175 u32 mgrsid = task_sid(mgr); 2176 2177 return avc_has_perm(&selinux_state, 2178 mysid, mgrsid, SECCLASS_BINDER, 2179 BINDER__SET_CONTEXT_MGR, NULL); 2180 } 2181 2182 static int selinux_binder_transaction(struct task_struct *from, 2183 struct task_struct *to) 2184 { 2185 u32 mysid = current_sid(); 2186 u32 fromsid = task_sid(from); 2187 u32 tosid = task_sid(to); 2188 int rc; 2189 2190 if (mysid != fromsid) { 2191 rc = avc_has_perm(&selinux_state, 2192 mysid, fromsid, SECCLASS_BINDER, 2193 BINDER__IMPERSONATE, NULL); 2194 if (rc) 2195 return rc; 2196 } 2197 2198 return avc_has_perm(&selinux_state, 2199 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, 2200 NULL); 2201 } 2202 2203 static int selinux_binder_transfer_binder(struct task_struct *from, 2204 struct task_struct *to) 2205 { 2206 u32 fromsid = task_sid(from); 2207 u32 tosid = task_sid(to); 2208 2209 return avc_has_perm(&selinux_state, 2210 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, 2211 NULL); 2212 } 2213 2214 static int selinux_binder_transfer_file(struct task_struct *from, 2215 struct task_struct *to, 2216 struct file *file) 2217 { 2218 u32 sid = task_sid(to); 2219 struct file_security_struct *fsec = file->f_security; 2220 struct dentry *dentry = file->f_path.dentry; 2221 struct inode_security_struct *isec; 2222 struct common_audit_data ad; 2223 int rc; 2224 2225 ad.type = LSM_AUDIT_DATA_PATH; 2226 ad.u.path = file->f_path; 2227 2228 if (sid != fsec->sid) { 2229 rc = avc_has_perm(&selinux_state, 2230 sid, fsec->sid, 2231 SECCLASS_FD, 2232 FD__USE, 2233 &ad); 2234 if (rc) 2235 return rc; 2236 } 2237 2238 #ifdef CONFIG_BPF_SYSCALL 2239 rc = bpf_fd_pass(file, sid); 2240 if (rc) 2241 return rc; 2242 #endif 2243 2244 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2245 return 0; 2246 2247 isec = backing_inode_security(dentry); 2248 return avc_has_perm(&selinux_state, 2249 sid, isec->sid, isec->sclass, file_to_av(file), 2250 &ad); 2251 } 2252 2253 static int selinux_ptrace_access_check(struct task_struct *child, 2254 unsigned int mode) 2255 { 2256 u32 sid = current_sid(); 2257 u32 csid = task_sid(child); 2258 2259 if (mode & PTRACE_MODE_READ) 2260 return avc_has_perm(&selinux_state, 2261 sid, csid, SECCLASS_FILE, FILE__READ, NULL); 2262 2263 return avc_has_perm(&selinux_state, 2264 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); 2265 } 2266 2267 static int selinux_ptrace_traceme(struct task_struct *parent) 2268 { 2269 return avc_has_perm(&selinux_state, 2270 task_sid(parent), current_sid(), SECCLASS_PROCESS, 2271 PROCESS__PTRACE, NULL); 2272 } 2273 2274 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 2275 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2276 { 2277 return avc_has_perm(&selinux_state, 2278 current_sid(), task_sid(target), SECCLASS_PROCESS, 2279 PROCESS__GETCAP, NULL); 2280 } 2281 2282 static int selinux_capset(struct cred *new, const struct cred *old, 2283 const kernel_cap_t *effective, 2284 const kernel_cap_t *inheritable, 2285 const kernel_cap_t *permitted) 2286 { 2287 return avc_has_perm(&selinux_state, 2288 cred_sid(old), cred_sid(new), SECCLASS_PROCESS, 2289 PROCESS__SETCAP, NULL); 2290 } 2291 2292 /* 2293 * (This comment used to live with the selinux_task_setuid hook, 2294 * which was removed). 2295 * 2296 * Since setuid only affects the current process, and since the SELinux 2297 * controls are not based on the Linux identity attributes, SELinux does not 2298 * need to control this operation. However, SELinux does control the use of 2299 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2300 */ 2301 2302 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2303 int cap, int audit) 2304 { 2305 return cred_has_capability(cred, cap, audit, ns == &init_user_ns); 2306 } 2307 2308 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2309 { 2310 const struct cred *cred = current_cred(); 2311 int rc = 0; 2312 2313 if (!sb) 2314 return 0; 2315 2316 switch (cmds) { 2317 case Q_SYNC: 2318 case Q_QUOTAON: 2319 case Q_QUOTAOFF: 2320 case Q_SETINFO: 2321 case Q_SETQUOTA: 2322 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2323 break; 2324 case Q_GETFMT: 2325 case Q_GETINFO: 2326 case Q_GETQUOTA: 2327 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2328 break; 2329 default: 2330 rc = 0; /* let the kernel handle invalid cmds */ 2331 break; 2332 } 2333 return rc; 2334 } 2335 2336 static int selinux_quota_on(struct dentry *dentry) 2337 { 2338 const struct cred *cred = current_cred(); 2339 2340 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2341 } 2342 2343 static int selinux_syslog(int type) 2344 { 2345 switch (type) { 2346 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2347 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2348 return avc_has_perm(&selinux_state, 2349 current_sid(), SECINITSID_KERNEL, 2350 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); 2351 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2352 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2353 /* Set level of messages printed to console */ 2354 case SYSLOG_ACTION_CONSOLE_LEVEL: 2355 return avc_has_perm(&selinux_state, 2356 current_sid(), SECINITSID_KERNEL, 2357 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, 2358 NULL); 2359 } 2360 /* All other syslog types */ 2361 return avc_has_perm(&selinux_state, 2362 current_sid(), SECINITSID_KERNEL, 2363 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); 2364 } 2365 2366 /* 2367 * Check that a process has enough memory to allocate a new virtual 2368 * mapping. 0 means there is enough memory for the allocation to 2369 * succeed and -ENOMEM implies there is not. 2370 * 2371 * Do not audit the selinux permission check, as this is applied to all 2372 * processes that allocate mappings. 2373 */ 2374 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2375 { 2376 int rc, cap_sys_admin = 0; 2377 2378 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2379 SECURITY_CAP_NOAUDIT, true); 2380 if (rc == 0) 2381 cap_sys_admin = 1; 2382 2383 return cap_sys_admin; 2384 } 2385 2386 /* binprm security operations */ 2387 2388 static u32 ptrace_parent_sid(void) 2389 { 2390 u32 sid = 0; 2391 struct task_struct *tracer; 2392 2393 rcu_read_lock(); 2394 tracer = ptrace_parent(current); 2395 if (tracer) 2396 sid = task_sid(tracer); 2397 rcu_read_unlock(); 2398 2399 return sid; 2400 } 2401 2402 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2403 const struct task_security_struct *old_tsec, 2404 const struct task_security_struct *new_tsec) 2405 { 2406 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2407 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2408 int rc; 2409 u32 av; 2410 2411 if (!nnp && !nosuid) 2412 return 0; /* neither NNP nor nosuid */ 2413 2414 if (new_tsec->sid == old_tsec->sid) 2415 return 0; /* No change in credentials */ 2416 2417 /* 2418 * If the policy enables the nnp_nosuid_transition policy capability, 2419 * then we permit transitions under NNP or nosuid if the 2420 * policy allows the corresponding permission between 2421 * the old and new contexts. 2422 */ 2423 if (selinux_policycap_nnp_nosuid_transition()) { 2424 av = 0; 2425 if (nnp) 2426 av |= PROCESS2__NNP_TRANSITION; 2427 if (nosuid) 2428 av |= PROCESS2__NOSUID_TRANSITION; 2429 rc = avc_has_perm(&selinux_state, 2430 old_tsec->sid, new_tsec->sid, 2431 SECCLASS_PROCESS2, av, NULL); 2432 if (!rc) 2433 return 0; 2434 } 2435 2436 /* 2437 * We also permit NNP or nosuid transitions to bounded SIDs, 2438 * i.e. SIDs that are guaranteed to only be allowed a subset 2439 * of the permissions of the current SID. 2440 */ 2441 rc = security_bounded_transition(&selinux_state, old_tsec->sid, 2442 new_tsec->sid); 2443 if (!rc) 2444 return 0; 2445 2446 /* 2447 * On failure, preserve the errno values for NNP vs nosuid. 2448 * NNP: Operation not permitted for caller. 2449 * nosuid: Permission denied to file. 2450 */ 2451 if (nnp) 2452 return -EPERM; 2453 return -EACCES; 2454 } 2455 2456 static int selinux_bprm_set_creds(struct linux_binprm *bprm) 2457 { 2458 const struct task_security_struct *old_tsec; 2459 struct task_security_struct *new_tsec; 2460 struct inode_security_struct *isec; 2461 struct common_audit_data ad; 2462 struct inode *inode = file_inode(bprm->file); 2463 int rc; 2464 2465 /* SELinux context only depends on initial program or script and not 2466 * the script interpreter */ 2467 if (bprm->called_set_creds) 2468 return 0; 2469 2470 old_tsec = current_security(); 2471 new_tsec = bprm->cred->security; 2472 isec = inode_security(inode); 2473 2474 /* Default to the current task SID. */ 2475 new_tsec->sid = old_tsec->sid; 2476 new_tsec->osid = old_tsec->sid; 2477 2478 /* Reset fs, key, and sock SIDs on execve. */ 2479 new_tsec->create_sid = 0; 2480 new_tsec->keycreate_sid = 0; 2481 new_tsec->sockcreate_sid = 0; 2482 2483 if (old_tsec->exec_sid) { 2484 new_tsec->sid = old_tsec->exec_sid; 2485 /* Reset exec SID on execve. */ 2486 new_tsec->exec_sid = 0; 2487 2488 /* Fail on NNP or nosuid if not an allowed transition. */ 2489 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2490 if (rc) 2491 return rc; 2492 } else { 2493 /* Check for a default transition on this program. */ 2494 rc = security_transition_sid(&selinux_state, old_tsec->sid, 2495 isec->sid, SECCLASS_PROCESS, NULL, 2496 &new_tsec->sid); 2497 if (rc) 2498 return rc; 2499 2500 /* 2501 * Fallback to old SID on NNP or nosuid if not an allowed 2502 * transition. 2503 */ 2504 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2505 if (rc) 2506 new_tsec->sid = old_tsec->sid; 2507 } 2508 2509 ad.type = LSM_AUDIT_DATA_FILE; 2510 ad.u.file = bprm->file; 2511 2512 if (new_tsec->sid == old_tsec->sid) { 2513 rc = avc_has_perm(&selinux_state, 2514 old_tsec->sid, isec->sid, 2515 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2516 if (rc) 2517 return rc; 2518 } else { 2519 /* Check permissions for the transition. */ 2520 rc = avc_has_perm(&selinux_state, 2521 old_tsec->sid, new_tsec->sid, 2522 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2523 if (rc) 2524 return rc; 2525 2526 rc = avc_has_perm(&selinux_state, 2527 new_tsec->sid, isec->sid, 2528 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2529 if (rc) 2530 return rc; 2531 2532 /* Check for shared state */ 2533 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2534 rc = avc_has_perm(&selinux_state, 2535 old_tsec->sid, new_tsec->sid, 2536 SECCLASS_PROCESS, PROCESS__SHARE, 2537 NULL); 2538 if (rc) 2539 return -EPERM; 2540 } 2541 2542 /* Make sure that anyone attempting to ptrace over a task that 2543 * changes its SID has the appropriate permit */ 2544 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 2545 u32 ptsid = ptrace_parent_sid(); 2546 if (ptsid != 0) { 2547 rc = avc_has_perm(&selinux_state, 2548 ptsid, new_tsec->sid, 2549 SECCLASS_PROCESS, 2550 PROCESS__PTRACE, NULL); 2551 if (rc) 2552 return -EPERM; 2553 } 2554 } 2555 2556 /* Clear any possibly unsafe personality bits on exec: */ 2557 bprm->per_clear |= PER_CLEAR_ON_SETID; 2558 2559 /* Enable secure mode for SIDs transitions unless 2560 the noatsecure permission is granted between 2561 the two SIDs, i.e. ahp returns 0. */ 2562 rc = avc_has_perm(&selinux_state, 2563 old_tsec->sid, new_tsec->sid, 2564 SECCLASS_PROCESS, PROCESS__NOATSECURE, 2565 NULL); 2566 bprm->secureexec |= !!rc; 2567 } 2568 2569 return 0; 2570 } 2571 2572 static int match_file(const void *p, struct file *file, unsigned fd) 2573 { 2574 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2575 } 2576 2577 /* Derived from fs/exec.c:flush_old_files. */ 2578 static inline void flush_unauthorized_files(const struct cred *cred, 2579 struct files_struct *files) 2580 { 2581 struct file *file, *devnull = NULL; 2582 struct tty_struct *tty; 2583 int drop_tty = 0; 2584 unsigned n; 2585 2586 tty = get_current_tty(); 2587 if (tty) { 2588 spin_lock(&tty->files_lock); 2589 if (!list_empty(&tty->tty_files)) { 2590 struct tty_file_private *file_priv; 2591 2592 /* Revalidate access to controlling tty. 2593 Use file_path_has_perm on the tty path directly 2594 rather than using file_has_perm, as this particular 2595 open file may belong to another process and we are 2596 only interested in the inode-based check here. */ 2597 file_priv = list_first_entry(&tty->tty_files, 2598 struct tty_file_private, list); 2599 file = file_priv->file; 2600 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2601 drop_tty = 1; 2602 } 2603 spin_unlock(&tty->files_lock); 2604 tty_kref_put(tty); 2605 } 2606 /* Reset controlling tty. */ 2607 if (drop_tty) 2608 no_tty(); 2609 2610 /* Revalidate access to inherited open files. */ 2611 n = iterate_fd(files, 0, match_file, cred); 2612 if (!n) /* none found? */ 2613 return; 2614 2615 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2616 if (IS_ERR(devnull)) 2617 devnull = NULL; 2618 /* replace all the matching ones with this */ 2619 do { 2620 replace_fd(n - 1, devnull, 0); 2621 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2622 if (devnull) 2623 fput(devnull); 2624 } 2625 2626 /* 2627 * Prepare a process for imminent new credential changes due to exec 2628 */ 2629 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2630 { 2631 struct task_security_struct *new_tsec; 2632 struct rlimit *rlim, *initrlim; 2633 int rc, i; 2634 2635 new_tsec = bprm->cred->security; 2636 if (new_tsec->sid == new_tsec->osid) 2637 return; 2638 2639 /* Close files for which the new task SID is not authorized. */ 2640 flush_unauthorized_files(bprm->cred, current->files); 2641 2642 /* Always clear parent death signal on SID transitions. */ 2643 current->pdeath_signal = 0; 2644 2645 /* Check whether the new SID can inherit resource limits from the old 2646 * SID. If not, reset all soft limits to the lower of the current 2647 * task's hard limit and the init task's soft limit. 2648 * 2649 * Note that the setting of hard limits (even to lower them) can be 2650 * controlled by the setrlimit check. The inclusion of the init task's 2651 * soft limit into the computation is to avoid resetting soft limits 2652 * higher than the default soft limit for cases where the default is 2653 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2654 */ 2655 rc = avc_has_perm(&selinux_state, 2656 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2657 PROCESS__RLIMITINH, NULL); 2658 if (rc) { 2659 /* protect against do_prlimit() */ 2660 task_lock(current); 2661 for (i = 0; i < RLIM_NLIMITS; i++) { 2662 rlim = current->signal->rlim + i; 2663 initrlim = init_task.signal->rlim + i; 2664 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2665 } 2666 task_unlock(current); 2667 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2668 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2669 } 2670 } 2671 2672 /* 2673 * Clean up the process immediately after the installation of new credentials 2674 * due to exec 2675 */ 2676 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2677 { 2678 const struct task_security_struct *tsec = current_security(); 2679 struct itimerval itimer; 2680 u32 osid, sid; 2681 int rc, i; 2682 2683 osid = tsec->osid; 2684 sid = tsec->sid; 2685 2686 if (sid == osid) 2687 return; 2688 2689 /* Check whether the new SID can inherit signal state from the old SID. 2690 * If not, clear itimers to avoid subsequent signal generation and 2691 * flush and unblock signals. 2692 * 2693 * This must occur _after_ the task SID has been updated so that any 2694 * kill done after the flush will be checked against the new SID. 2695 */ 2696 rc = avc_has_perm(&selinux_state, 2697 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2698 if (rc) { 2699 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { 2700 memset(&itimer, 0, sizeof itimer); 2701 for (i = 0; i < 3; i++) 2702 do_setitimer(i, &itimer, NULL); 2703 } 2704 spin_lock_irq(¤t->sighand->siglock); 2705 if (!fatal_signal_pending(current)) { 2706 flush_sigqueue(¤t->pending); 2707 flush_sigqueue(¤t->signal->shared_pending); 2708 flush_signal_handlers(current, 1); 2709 sigemptyset(¤t->blocked); 2710 recalc_sigpending(); 2711 } 2712 spin_unlock_irq(¤t->sighand->siglock); 2713 } 2714 2715 /* Wake up the parent if it is waiting so that it can recheck 2716 * wait permission to the new task SID. */ 2717 read_lock(&tasklist_lock); 2718 __wake_up_parent(current, current->real_parent); 2719 read_unlock(&tasklist_lock); 2720 } 2721 2722 /* superblock security operations */ 2723 2724 static int selinux_sb_alloc_security(struct super_block *sb) 2725 { 2726 return superblock_alloc_security(sb); 2727 } 2728 2729 static void selinux_sb_free_security(struct super_block *sb) 2730 { 2731 superblock_free_security(sb); 2732 } 2733 2734 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2735 { 2736 if (plen > olen) 2737 return 0; 2738 2739 return !memcmp(prefix, option, plen); 2740 } 2741 2742 static inline int selinux_option(char *option, int len) 2743 { 2744 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2745 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2746 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2747 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2748 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2749 } 2750 2751 static inline void take_option(char **to, char *from, int *first, int len) 2752 { 2753 if (!*first) { 2754 **to = ','; 2755 *to += 1; 2756 } else 2757 *first = 0; 2758 memcpy(*to, from, len); 2759 *to += len; 2760 } 2761 2762 static inline void take_selinux_option(char **to, char *from, int *first, 2763 int len) 2764 { 2765 int current_size = 0; 2766 2767 if (!*first) { 2768 **to = '|'; 2769 *to += 1; 2770 } else 2771 *first = 0; 2772 2773 while (current_size < len) { 2774 if (*from != '"') { 2775 **to = *from; 2776 *to += 1; 2777 } 2778 from += 1; 2779 current_size += 1; 2780 } 2781 } 2782 2783 static int selinux_sb_copy_data(char *orig, char *copy) 2784 { 2785 int fnosec, fsec, rc = 0; 2786 char *in_save, *in_curr, *in_end; 2787 char *sec_curr, *nosec_save, *nosec; 2788 int open_quote = 0; 2789 2790 in_curr = orig; 2791 sec_curr = copy; 2792 2793 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2794 if (!nosec) { 2795 rc = -ENOMEM; 2796 goto out; 2797 } 2798 2799 nosec_save = nosec; 2800 fnosec = fsec = 1; 2801 in_save = in_end = orig; 2802 2803 do { 2804 if (*in_end == '"') 2805 open_quote = !open_quote; 2806 if ((*in_end == ',' && open_quote == 0) || 2807 *in_end == '\0') { 2808 int len = in_end - in_curr; 2809 2810 if (selinux_option(in_curr, len)) 2811 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2812 else 2813 take_option(&nosec, in_curr, &fnosec, len); 2814 2815 in_curr = in_end + 1; 2816 } 2817 } while (*in_end++); 2818 2819 strcpy(in_save, nosec_save); 2820 free_page((unsigned long)nosec_save); 2821 out: 2822 return rc; 2823 } 2824 2825 static int selinux_sb_remount(struct super_block *sb, void *data) 2826 { 2827 int rc, i, *flags; 2828 struct security_mnt_opts opts; 2829 char *secdata, **mount_options; 2830 struct superblock_security_struct *sbsec = sb->s_security; 2831 2832 if (!(sbsec->flags & SE_SBINITIALIZED)) 2833 return 0; 2834 2835 if (!data) 2836 return 0; 2837 2838 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 2839 return 0; 2840 2841 security_init_mnt_opts(&opts); 2842 secdata = alloc_secdata(); 2843 if (!secdata) 2844 return -ENOMEM; 2845 rc = selinux_sb_copy_data(data, secdata); 2846 if (rc) 2847 goto out_free_secdata; 2848 2849 rc = selinux_parse_opts_str(secdata, &opts); 2850 if (rc) 2851 goto out_free_secdata; 2852 2853 mount_options = opts.mnt_opts; 2854 flags = opts.mnt_opts_flags; 2855 2856 for (i = 0; i < opts.num_mnt_opts; i++) { 2857 u32 sid; 2858 2859 if (flags[i] == SBLABEL_MNT) 2860 continue; 2861 rc = security_context_str_to_sid(&selinux_state, 2862 mount_options[i], &sid, 2863 GFP_KERNEL); 2864 if (rc) { 2865 printk(KERN_WARNING "SELinux: security_context_str_to_sid" 2866 "(%s) failed for (dev %s, type %s) errno=%d\n", 2867 mount_options[i], sb->s_id, sb->s_type->name, rc); 2868 goto out_free_opts; 2869 } 2870 rc = -EINVAL; 2871 switch (flags[i]) { 2872 case FSCONTEXT_MNT: 2873 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2874 goto out_bad_option; 2875 break; 2876 case CONTEXT_MNT: 2877 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2878 goto out_bad_option; 2879 break; 2880 case ROOTCONTEXT_MNT: { 2881 struct inode_security_struct *root_isec; 2882 root_isec = backing_inode_security(sb->s_root); 2883 2884 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2885 goto out_bad_option; 2886 break; 2887 } 2888 case DEFCONTEXT_MNT: 2889 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2890 goto out_bad_option; 2891 break; 2892 default: 2893 goto out_free_opts; 2894 } 2895 } 2896 2897 rc = 0; 2898 out_free_opts: 2899 security_free_mnt_opts(&opts); 2900 out_free_secdata: 2901 free_secdata(secdata); 2902 return rc; 2903 out_bad_option: 2904 printk(KERN_WARNING "SELinux: unable to change security options " 2905 "during remount (dev %s, type=%s)\n", sb->s_id, 2906 sb->s_type->name); 2907 goto out_free_opts; 2908 } 2909 2910 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2911 { 2912 const struct cred *cred = current_cred(); 2913 struct common_audit_data ad; 2914 int rc; 2915 2916 rc = superblock_doinit(sb, data); 2917 if (rc) 2918 return rc; 2919 2920 /* Allow all mounts performed by the kernel */ 2921 if (flags & MS_KERNMOUNT) 2922 return 0; 2923 2924 ad.type = LSM_AUDIT_DATA_DENTRY; 2925 ad.u.dentry = sb->s_root; 2926 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2927 } 2928 2929 static int selinux_sb_statfs(struct dentry *dentry) 2930 { 2931 const struct cred *cred = current_cred(); 2932 struct common_audit_data ad; 2933 2934 ad.type = LSM_AUDIT_DATA_DENTRY; 2935 ad.u.dentry = dentry->d_sb->s_root; 2936 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2937 } 2938 2939 static int selinux_mount(const char *dev_name, 2940 const struct path *path, 2941 const char *type, 2942 unsigned long flags, 2943 void *data) 2944 { 2945 const struct cred *cred = current_cred(); 2946 2947 if (flags & MS_REMOUNT) 2948 return superblock_has_perm(cred, path->dentry->d_sb, 2949 FILESYSTEM__REMOUNT, NULL); 2950 else 2951 return path_has_perm(cred, path, FILE__MOUNTON); 2952 } 2953 2954 static int selinux_umount(struct vfsmount *mnt, int flags) 2955 { 2956 const struct cred *cred = current_cred(); 2957 2958 return superblock_has_perm(cred, mnt->mnt_sb, 2959 FILESYSTEM__UNMOUNT, NULL); 2960 } 2961 2962 /* inode security operations */ 2963 2964 static int selinux_inode_alloc_security(struct inode *inode) 2965 { 2966 return inode_alloc_security(inode); 2967 } 2968 2969 static void selinux_inode_free_security(struct inode *inode) 2970 { 2971 inode_free_security(inode); 2972 } 2973 2974 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2975 const struct qstr *name, void **ctx, 2976 u32 *ctxlen) 2977 { 2978 u32 newsid; 2979 int rc; 2980 2981 rc = selinux_determine_inode_label(current_security(), 2982 d_inode(dentry->d_parent), name, 2983 inode_mode_to_security_class(mode), 2984 &newsid); 2985 if (rc) 2986 return rc; 2987 2988 return security_sid_to_context(&selinux_state, newsid, (char **)ctx, 2989 ctxlen); 2990 } 2991 2992 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2993 struct qstr *name, 2994 const struct cred *old, 2995 struct cred *new) 2996 { 2997 u32 newsid; 2998 int rc; 2999 struct task_security_struct *tsec; 3000 3001 rc = selinux_determine_inode_label(old->security, 3002 d_inode(dentry->d_parent), name, 3003 inode_mode_to_security_class(mode), 3004 &newsid); 3005 if (rc) 3006 return rc; 3007 3008 tsec = new->security; 3009 tsec->create_sid = newsid; 3010 return 0; 3011 } 3012 3013 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 3014 const struct qstr *qstr, 3015 const char **name, 3016 void **value, size_t *len) 3017 { 3018 const struct task_security_struct *tsec = current_security(); 3019 struct superblock_security_struct *sbsec; 3020 u32 newsid, clen; 3021 int rc; 3022 char *context; 3023 3024 sbsec = dir->i_sb->s_security; 3025 3026 newsid = tsec->create_sid; 3027 3028 rc = selinux_determine_inode_label(current_security(), 3029 dir, qstr, 3030 inode_mode_to_security_class(inode->i_mode), 3031 &newsid); 3032 if (rc) 3033 return rc; 3034 3035 /* Possibly defer initialization to selinux_complete_init. */ 3036 if (sbsec->flags & SE_SBINITIALIZED) { 3037 struct inode_security_struct *isec = inode->i_security; 3038 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3039 isec->sid = newsid; 3040 isec->initialized = LABEL_INITIALIZED; 3041 } 3042 3043 if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT)) 3044 return -EOPNOTSUPP; 3045 3046 if (name) 3047 *name = XATTR_SELINUX_SUFFIX; 3048 3049 if (value && len) { 3050 rc = security_sid_to_context_force(&selinux_state, newsid, 3051 &context, &clen); 3052 if (rc) 3053 return rc; 3054 *value = context; 3055 *len = clen; 3056 } 3057 3058 return 0; 3059 } 3060 3061 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3062 { 3063 return may_create(dir, dentry, SECCLASS_FILE); 3064 } 3065 3066 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3067 { 3068 return may_link(dir, old_dentry, MAY_LINK); 3069 } 3070 3071 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3072 { 3073 return may_link(dir, dentry, MAY_UNLINK); 3074 } 3075 3076 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3077 { 3078 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3079 } 3080 3081 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3082 { 3083 return may_create(dir, dentry, SECCLASS_DIR); 3084 } 3085 3086 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3087 { 3088 return may_link(dir, dentry, MAY_RMDIR); 3089 } 3090 3091 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3092 { 3093 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3094 } 3095 3096 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3097 struct inode *new_inode, struct dentry *new_dentry) 3098 { 3099 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3100 } 3101 3102 static int selinux_inode_readlink(struct dentry *dentry) 3103 { 3104 const struct cred *cred = current_cred(); 3105 3106 return dentry_has_perm(cred, dentry, FILE__READ); 3107 } 3108 3109 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3110 bool rcu) 3111 { 3112 const struct cred *cred = current_cred(); 3113 struct common_audit_data ad; 3114 struct inode_security_struct *isec; 3115 u32 sid; 3116 3117 validate_creds(cred); 3118 3119 ad.type = LSM_AUDIT_DATA_DENTRY; 3120 ad.u.dentry = dentry; 3121 sid = cred_sid(cred); 3122 isec = inode_security_rcu(inode, rcu); 3123 if (IS_ERR(isec)) 3124 return PTR_ERR(isec); 3125 3126 return avc_has_perm_flags(&selinux_state, 3127 sid, isec->sid, isec->sclass, FILE__READ, &ad, 3128 rcu ? MAY_NOT_BLOCK : 0); 3129 } 3130 3131 static noinline int audit_inode_permission(struct inode *inode, 3132 u32 perms, u32 audited, u32 denied, 3133 int result, 3134 unsigned flags) 3135 { 3136 struct common_audit_data ad; 3137 struct inode_security_struct *isec = inode->i_security; 3138 int rc; 3139 3140 ad.type = LSM_AUDIT_DATA_INODE; 3141 ad.u.inode = inode; 3142 3143 rc = slow_avc_audit(&selinux_state, 3144 current_sid(), isec->sid, isec->sclass, perms, 3145 audited, denied, result, &ad, flags); 3146 if (rc) 3147 return rc; 3148 return 0; 3149 } 3150 3151 static int selinux_inode_permission(struct inode *inode, int mask) 3152 { 3153 const struct cred *cred = current_cred(); 3154 u32 perms; 3155 bool from_access; 3156 unsigned flags = mask & MAY_NOT_BLOCK; 3157 struct inode_security_struct *isec; 3158 u32 sid; 3159 struct av_decision avd; 3160 int rc, rc2; 3161 u32 audited, denied; 3162 3163 from_access = mask & MAY_ACCESS; 3164 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3165 3166 /* No permission to check. Existence test. */ 3167 if (!mask) 3168 return 0; 3169 3170 validate_creds(cred); 3171 3172 if (unlikely(IS_PRIVATE(inode))) 3173 return 0; 3174 3175 perms = file_mask_to_av(inode->i_mode, mask); 3176 3177 sid = cred_sid(cred); 3178 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); 3179 if (IS_ERR(isec)) 3180 return PTR_ERR(isec); 3181 3182 rc = avc_has_perm_noaudit(&selinux_state, 3183 sid, isec->sid, isec->sclass, perms, 0, &avd); 3184 audited = avc_audit_required(perms, &avd, rc, 3185 from_access ? FILE__AUDIT_ACCESS : 0, 3186 &denied); 3187 if (likely(!audited)) 3188 return rc; 3189 3190 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); 3191 if (rc2) 3192 return rc2; 3193 return rc; 3194 } 3195 3196 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3197 { 3198 const struct cred *cred = current_cred(); 3199 struct inode *inode = d_backing_inode(dentry); 3200 unsigned int ia_valid = iattr->ia_valid; 3201 __u32 av = FILE__WRITE; 3202 3203 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3204 if (ia_valid & ATTR_FORCE) { 3205 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3206 ATTR_FORCE); 3207 if (!ia_valid) 3208 return 0; 3209 } 3210 3211 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3212 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3213 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3214 3215 if (selinux_policycap_openperm() && 3216 inode->i_sb->s_magic != SOCKFS_MAGIC && 3217 (ia_valid & ATTR_SIZE) && 3218 !(ia_valid & ATTR_FILE)) 3219 av |= FILE__OPEN; 3220 3221 return dentry_has_perm(cred, dentry, av); 3222 } 3223 3224 static int selinux_inode_getattr(const struct path *path) 3225 { 3226 return path_has_perm(current_cred(), path, FILE__GETATTR); 3227 } 3228 3229 static bool has_cap_mac_admin(bool audit) 3230 { 3231 const struct cred *cred = current_cred(); 3232 int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT; 3233 3234 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit)) 3235 return false; 3236 if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true)) 3237 return false; 3238 return true; 3239 } 3240 3241 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 3242 const void *value, size_t size, int flags) 3243 { 3244 struct inode *inode = d_backing_inode(dentry); 3245 struct inode_security_struct *isec; 3246 struct superblock_security_struct *sbsec; 3247 struct common_audit_data ad; 3248 u32 newsid, sid = current_sid(); 3249 int rc = 0; 3250 3251 if (strcmp(name, XATTR_NAME_SELINUX)) { 3252 rc = cap_inode_setxattr(dentry, name, value, size, flags); 3253 if (rc) 3254 return rc; 3255 3256 /* Not an attribute we recognize, so just check the 3257 ordinary setattr permission. */ 3258 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3259 } 3260 3261 sbsec = inode->i_sb->s_security; 3262 if (!(sbsec->flags & SBLABEL_MNT)) 3263 return -EOPNOTSUPP; 3264 3265 if (!inode_owner_or_capable(inode)) 3266 return -EPERM; 3267 3268 ad.type = LSM_AUDIT_DATA_DENTRY; 3269 ad.u.dentry = dentry; 3270 3271 isec = backing_inode_security(dentry); 3272 rc = avc_has_perm(&selinux_state, 3273 sid, isec->sid, isec->sclass, 3274 FILE__RELABELFROM, &ad); 3275 if (rc) 3276 return rc; 3277 3278 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3279 GFP_KERNEL); 3280 if (rc == -EINVAL) { 3281 if (!has_cap_mac_admin(true)) { 3282 struct audit_buffer *ab; 3283 size_t audit_size; 3284 3285 /* We strip a nul only if it is at the end, otherwise the 3286 * context contains a nul and we should audit that */ 3287 if (value) { 3288 const char *str = value; 3289 3290 if (str[size - 1] == '\0') 3291 audit_size = size - 1; 3292 else 3293 audit_size = size; 3294 } else { 3295 audit_size = 0; 3296 } 3297 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); 3298 audit_log_format(ab, "op=setxattr invalid_context="); 3299 audit_log_n_untrustedstring(ab, value, audit_size); 3300 audit_log_end(ab); 3301 3302 return rc; 3303 } 3304 rc = security_context_to_sid_force(&selinux_state, value, 3305 size, &newsid); 3306 } 3307 if (rc) 3308 return rc; 3309 3310 rc = avc_has_perm(&selinux_state, 3311 sid, newsid, isec->sclass, 3312 FILE__RELABELTO, &ad); 3313 if (rc) 3314 return rc; 3315 3316 rc = security_validate_transition(&selinux_state, isec->sid, newsid, 3317 sid, isec->sclass); 3318 if (rc) 3319 return rc; 3320 3321 return avc_has_perm(&selinux_state, 3322 newsid, 3323 sbsec->sid, 3324 SECCLASS_FILESYSTEM, 3325 FILESYSTEM__ASSOCIATE, 3326 &ad); 3327 } 3328 3329 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3330 const void *value, size_t size, 3331 int flags) 3332 { 3333 struct inode *inode = d_backing_inode(dentry); 3334 struct inode_security_struct *isec; 3335 u32 newsid; 3336 int rc; 3337 3338 if (strcmp(name, XATTR_NAME_SELINUX)) { 3339 /* Not an attribute we recognize, so nothing to do. */ 3340 return; 3341 } 3342 3343 rc = security_context_to_sid_force(&selinux_state, value, size, 3344 &newsid); 3345 if (rc) { 3346 printk(KERN_ERR "SELinux: unable to map context to SID" 3347 "for (%s, %lu), rc=%d\n", 3348 inode->i_sb->s_id, inode->i_ino, -rc); 3349 return; 3350 } 3351 3352 isec = backing_inode_security(dentry); 3353 spin_lock(&isec->lock); 3354 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3355 isec->sid = newsid; 3356 isec->initialized = LABEL_INITIALIZED; 3357 spin_unlock(&isec->lock); 3358 3359 return; 3360 } 3361 3362 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3363 { 3364 const struct cred *cred = current_cred(); 3365 3366 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3367 } 3368 3369 static int selinux_inode_listxattr(struct dentry *dentry) 3370 { 3371 const struct cred *cred = current_cred(); 3372 3373 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3374 } 3375 3376 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 3377 { 3378 if (strcmp(name, XATTR_NAME_SELINUX)) { 3379 int rc = cap_inode_removexattr(dentry, name); 3380 if (rc) 3381 return rc; 3382 3383 /* Not an attribute we recognize, so just check the 3384 ordinary setattr permission. */ 3385 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); 3386 } 3387 3388 /* No one is allowed to remove a SELinux security label. 3389 You can change the label, but all data must be labeled. */ 3390 return -EACCES; 3391 } 3392 3393 /* 3394 * Copy the inode security context value to the user. 3395 * 3396 * Permission check is handled by selinux_inode_getxattr hook. 3397 */ 3398 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) 3399 { 3400 u32 size; 3401 int error; 3402 char *context = NULL; 3403 struct inode_security_struct *isec; 3404 3405 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3406 return -EOPNOTSUPP; 3407 3408 /* 3409 * If the caller has CAP_MAC_ADMIN, then get the raw context 3410 * value even if it is not defined by current policy; otherwise, 3411 * use the in-core value under current policy. 3412 * Use the non-auditing forms of the permission checks since 3413 * getxattr may be called by unprivileged processes commonly 3414 * and lack of permission just means that we fall back to the 3415 * in-core context value, not a denial. 3416 */ 3417 isec = inode_security(inode); 3418 if (has_cap_mac_admin(false)) 3419 error = security_sid_to_context_force(&selinux_state, 3420 isec->sid, &context, 3421 &size); 3422 else 3423 error = security_sid_to_context(&selinux_state, isec->sid, 3424 &context, &size); 3425 if (error) 3426 return error; 3427 error = size; 3428 if (alloc) { 3429 *buffer = context; 3430 goto out_nofree; 3431 } 3432 kfree(context); 3433 out_nofree: 3434 return error; 3435 } 3436 3437 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3438 const void *value, size_t size, int flags) 3439 { 3440 struct inode_security_struct *isec = inode_security_novalidate(inode); 3441 u32 newsid; 3442 int rc; 3443 3444 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3445 return -EOPNOTSUPP; 3446 3447 if (!value || !size) 3448 return -EACCES; 3449 3450 rc = security_context_to_sid(&selinux_state, value, size, &newsid, 3451 GFP_KERNEL); 3452 if (rc) 3453 return rc; 3454 3455 spin_lock(&isec->lock); 3456 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3457 isec->sid = newsid; 3458 isec->initialized = LABEL_INITIALIZED; 3459 spin_unlock(&isec->lock); 3460 return 0; 3461 } 3462 3463 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3464 { 3465 const int len = sizeof(XATTR_NAME_SELINUX); 3466 if (buffer && len <= buffer_size) 3467 memcpy(buffer, XATTR_NAME_SELINUX, len); 3468 return len; 3469 } 3470 3471 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3472 { 3473 struct inode_security_struct *isec = inode_security_novalidate(inode); 3474 *secid = isec->sid; 3475 } 3476 3477 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3478 { 3479 u32 sid; 3480 struct task_security_struct *tsec; 3481 struct cred *new_creds = *new; 3482 3483 if (new_creds == NULL) { 3484 new_creds = prepare_creds(); 3485 if (!new_creds) 3486 return -ENOMEM; 3487 } 3488 3489 tsec = new_creds->security; 3490 /* Get label from overlay inode and set it in create_sid */ 3491 selinux_inode_getsecid(d_inode(src), &sid); 3492 tsec->create_sid = sid; 3493 *new = new_creds; 3494 return 0; 3495 } 3496 3497 static int selinux_inode_copy_up_xattr(const char *name) 3498 { 3499 /* The copy_up hook above sets the initial context on an inode, but we 3500 * don't then want to overwrite it by blindly copying all the lower 3501 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3502 */ 3503 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3504 return 1; /* Discard */ 3505 /* 3506 * Any other attribute apart from SELINUX is not claimed, supported 3507 * by selinux. 3508 */ 3509 return -EOPNOTSUPP; 3510 } 3511 3512 /* file security operations */ 3513 3514 static int selinux_revalidate_file_permission(struct file *file, int mask) 3515 { 3516 const struct cred *cred = current_cred(); 3517 struct inode *inode = file_inode(file); 3518 3519 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3520 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3521 mask |= MAY_APPEND; 3522 3523 return file_has_perm(cred, file, 3524 file_mask_to_av(inode->i_mode, mask)); 3525 } 3526 3527 static int selinux_file_permission(struct file *file, int mask) 3528 { 3529 struct inode *inode = file_inode(file); 3530 struct file_security_struct *fsec = file->f_security; 3531 struct inode_security_struct *isec; 3532 u32 sid = current_sid(); 3533 3534 if (!mask) 3535 /* No permission to check. Existence test. */ 3536 return 0; 3537 3538 isec = inode_security(inode); 3539 if (sid == fsec->sid && fsec->isid == isec->sid && 3540 fsec->pseqno == avc_policy_seqno(&selinux_state)) 3541 /* No change since file_open check. */ 3542 return 0; 3543 3544 return selinux_revalidate_file_permission(file, mask); 3545 } 3546 3547 static int selinux_file_alloc_security(struct file *file) 3548 { 3549 return file_alloc_security(file); 3550 } 3551 3552 static void selinux_file_free_security(struct file *file) 3553 { 3554 file_free_security(file); 3555 } 3556 3557 /* 3558 * Check whether a task has the ioctl permission and cmd 3559 * operation to an inode. 3560 */ 3561 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3562 u32 requested, u16 cmd) 3563 { 3564 struct common_audit_data ad; 3565 struct file_security_struct *fsec = file->f_security; 3566 struct inode *inode = file_inode(file); 3567 struct inode_security_struct *isec; 3568 struct lsm_ioctlop_audit ioctl; 3569 u32 ssid = cred_sid(cred); 3570 int rc; 3571 u8 driver = cmd >> 8; 3572 u8 xperm = cmd & 0xff; 3573 3574 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3575 ad.u.op = &ioctl; 3576 ad.u.op->cmd = cmd; 3577 ad.u.op->path = file->f_path; 3578 3579 if (ssid != fsec->sid) { 3580 rc = avc_has_perm(&selinux_state, 3581 ssid, fsec->sid, 3582 SECCLASS_FD, 3583 FD__USE, 3584 &ad); 3585 if (rc) 3586 goto out; 3587 } 3588 3589 if (unlikely(IS_PRIVATE(inode))) 3590 return 0; 3591 3592 isec = inode_security(inode); 3593 rc = avc_has_extended_perms(&selinux_state, 3594 ssid, isec->sid, isec->sclass, 3595 requested, driver, xperm, &ad); 3596 out: 3597 return rc; 3598 } 3599 3600 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3601 unsigned long arg) 3602 { 3603 const struct cred *cred = current_cred(); 3604 int error = 0; 3605 3606 switch (cmd) { 3607 case FIONREAD: 3608 /* fall through */ 3609 case FIBMAP: 3610 /* fall through */ 3611 case FIGETBSZ: 3612 /* fall through */ 3613 case FS_IOC_GETFLAGS: 3614 /* fall through */ 3615 case FS_IOC_GETVERSION: 3616 error = file_has_perm(cred, file, FILE__GETATTR); 3617 break; 3618 3619 case FS_IOC_SETFLAGS: 3620 /* fall through */ 3621 case FS_IOC_SETVERSION: 3622 error = file_has_perm(cred, file, FILE__SETATTR); 3623 break; 3624 3625 /* sys_ioctl() checks */ 3626 case FIONBIO: 3627 /* fall through */ 3628 case FIOASYNC: 3629 error = file_has_perm(cred, file, 0); 3630 break; 3631 3632 case KDSKBENT: 3633 case KDSKBSENT: 3634 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3635 SECURITY_CAP_AUDIT, true); 3636 break; 3637 3638 /* default case assumes that the command will go 3639 * to the file's ioctl() function. 3640 */ 3641 default: 3642 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3643 } 3644 return error; 3645 } 3646 3647 static int default_noexec; 3648 3649 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3650 { 3651 const struct cred *cred = current_cred(); 3652 u32 sid = cred_sid(cred); 3653 int rc = 0; 3654 3655 if (default_noexec && 3656 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3657 (!shared && (prot & PROT_WRITE)))) { 3658 /* 3659 * We are making executable an anonymous mapping or a 3660 * private file mapping that will also be writable. 3661 * This has an additional check. 3662 */ 3663 rc = avc_has_perm(&selinux_state, 3664 sid, sid, SECCLASS_PROCESS, 3665 PROCESS__EXECMEM, NULL); 3666 if (rc) 3667 goto error; 3668 } 3669 3670 if (file) { 3671 /* read access is always possible with a mapping */ 3672 u32 av = FILE__READ; 3673 3674 /* write access only matters if the mapping is shared */ 3675 if (shared && (prot & PROT_WRITE)) 3676 av |= FILE__WRITE; 3677 3678 if (prot & PROT_EXEC) 3679 av |= FILE__EXECUTE; 3680 3681 return file_has_perm(cred, file, av); 3682 } 3683 3684 error: 3685 return rc; 3686 } 3687 3688 static int selinux_mmap_addr(unsigned long addr) 3689 { 3690 int rc = 0; 3691 3692 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3693 u32 sid = current_sid(); 3694 rc = avc_has_perm(&selinux_state, 3695 sid, sid, SECCLASS_MEMPROTECT, 3696 MEMPROTECT__MMAP_ZERO, NULL); 3697 } 3698 3699 return rc; 3700 } 3701 3702 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3703 unsigned long prot, unsigned long flags) 3704 { 3705 struct common_audit_data ad; 3706 int rc; 3707 3708 if (file) { 3709 ad.type = LSM_AUDIT_DATA_FILE; 3710 ad.u.file = file; 3711 rc = inode_has_perm(current_cred(), file_inode(file), 3712 FILE__MAP, &ad); 3713 if (rc) 3714 return rc; 3715 } 3716 3717 if (selinux_state.checkreqprot) 3718 prot = reqprot; 3719 3720 return file_map_prot_check(file, prot, 3721 (flags & MAP_TYPE) == MAP_SHARED); 3722 } 3723 3724 static int selinux_file_mprotect(struct vm_area_struct *vma, 3725 unsigned long reqprot, 3726 unsigned long prot) 3727 { 3728 const struct cred *cred = current_cred(); 3729 u32 sid = cred_sid(cred); 3730 3731 if (selinux_state.checkreqprot) 3732 prot = reqprot; 3733 3734 if (default_noexec && 3735 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3736 int rc = 0; 3737 if (vma->vm_start >= vma->vm_mm->start_brk && 3738 vma->vm_end <= vma->vm_mm->brk) { 3739 rc = avc_has_perm(&selinux_state, 3740 sid, sid, SECCLASS_PROCESS, 3741 PROCESS__EXECHEAP, NULL); 3742 } else if (!vma->vm_file && 3743 ((vma->vm_start <= vma->vm_mm->start_stack && 3744 vma->vm_end >= vma->vm_mm->start_stack) || 3745 vma_is_stack_for_current(vma))) { 3746 rc = avc_has_perm(&selinux_state, 3747 sid, sid, SECCLASS_PROCESS, 3748 PROCESS__EXECSTACK, NULL); 3749 } else if (vma->vm_file && vma->anon_vma) { 3750 /* 3751 * We are making executable a file mapping that has 3752 * had some COW done. Since pages might have been 3753 * written, check ability to execute the possibly 3754 * modified content. This typically should only 3755 * occur for text relocations. 3756 */ 3757 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3758 } 3759 if (rc) 3760 return rc; 3761 } 3762 3763 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3764 } 3765 3766 static int selinux_file_lock(struct file *file, unsigned int cmd) 3767 { 3768 const struct cred *cred = current_cred(); 3769 3770 return file_has_perm(cred, file, FILE__LOCK); 3771 } 3772 3773 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3774 unsigned long arg) 3775 { 3776 const struct cred *cred = current_cred(); 3777 int err = 0; 3778 3779 switch (cmd) { 3780 case F_SETFL: 3781 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3782 err = file_has_perm(cred, file, FILE__WRITE); 3783 break; 3784 } 3785 /* fall through */ 3786 case F_SETOWN: 3787 case F_SETSIG: 3788 case F_GETFL: 3789 case F_GETOWN: 3790 case F_GETSIG: 3791 case F_GETOWNER_UIDS: 3792 /* Just check FD__USE permission */ 3793 err = file_has_perm(cred, file, 0); 3794 break; 3795 case F_GETLK: 3796 case F_SETLK: 3797 case F_SETLKW: 3798 case F_OFD_GETLK: 3799 case F_OFD_SETLK: 3800 case F_OFD_SETLKW: 3801 #if BITS_PER_LONG == 32 3802 case F_GETLK64: 3803 case F_SETLK64: 3804 case F_SETLKW64: 3805 #endif 3806 err = file_has_perm(cred, file, FILE__LOCK); 3807 break; 3808 } 3809 3810 return err; 3811 } 3812 3813 static void selinux_file_set_fowner(struct file *file) 3814 { 3815 struct file_security_struct *fsec; 3816 3817 fsec = file->f_security; 3818 fsec->fown_sid = current_sid(); 3819 } 3820 3821 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3822 struct fown_struct *fown, int signum) 3823 { 3824 struct file *file; 3825 u32 sid = task_sid(tsk); 3826 u32 perm; 3827 struct file_security_struct *fsec; 3828 3829 /* struct fown_struct is never outside the context of a struct file */ 3830 file = container_of(fown, struct file, f_owner); 3831 3832 fsec = file->f_security; 3833 3834 if (!signum) 3835 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3836 else 3837 perm = signal_to_av(signum); 3838 3839 return avc_has_perm(&selinux_state, 3840 fsec->fown_sid, sid, 3841 SECCLASS_PROCESS, perm, NULL); 3842 } 3843 3844 static int selinux_file_receive(struct file *file) 3845 { 3846 const struct cred *cred = current_cred(); 3847 3848 return file_has_perm(cred, file, file_to_av(file)); 3849 } 3850 3851 static int selinux_file_open(struct file *file, const struct cred *cred) 3852 { 3853 struct file_security_struct *fsec; 3854 struct inode_security_struct *isec; 3855 3856 fsec = file->f_security; 3857 isec = inode_security(file_inode(file)); 3858 /* 3859 * Save inode label and policy sequence number 3860 * at open-time so that selinux_file_permission 3861 * can determine whether revalidation is necessary. 3862 * Task label is already saved in the file security 3863 * struct as its SID. 3864 */ 3865 fsec->isid = isec->sid; 3866 fsec->pseqno = avc_policy_seqno(&selinux_state); 3867 /* 3868 * Since the inode label or policy seqno may have changed 3869 * between the selinux_inode_permission check and the saving 3870 * of state above, recheck that access is still permitted. 3871 * Otherwise, access might never be revalidated against the 3872 * new inode label or new policy. 3873 * This check is not redundant - do not remove. 3874 */ 3875 return file_path_has_perm(cred, file, open_file_to_av(file)); 3876 } 3877 3878 /* task security operations */ 3879 3880 static int selinux_task_alloc(struct task_struct *task, 3881 unsigned long clone_flags) 3882 { 3883 u32 sid = current_sid(); 3884 3885 return avc_has_perm(&selinux_state, 3886 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); 3887 } 3888 3889 /* 3890 * allocate the SELinux part of blank credentials 3891 */ 3892 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3893 { 3894 struct task_security_struct *tsec; 3895 3896 tsec = kzalloc(sizeof(struct task_security_struct), gfp); 3897 if (!tsec) 3898 return -ENOMEM; 3899 3900 cred->security = tsec; 3901 return 0; 3902 } 3903 3904 /* 3905 * detach and free the LSM part of a set of credentials 3906 */ 3907 static void selinux_cred_free(struct cred *cred) 3908 { 3909 struct task_security_struct *tsec = cred->security; 3910 3911 /* 3912 * cred->security == NULL if security_cred_alloc_blank() or 3913 * security_prepare_creds() returned an error. 3914 */ 3915 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); 3916 cred->security = (void *) 0x7UL; 3917 kfree(tsec); 3918 } 3919 3920 /* 3921 * prepare a new set of credentials for modification 3922 */ 3923 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3924 gfp_t gfp) 3925 { 3926 const struct task_security_struct *old_tsec; 3927 struct task_security_struct *tsec; 3928 3929 old_tsec = old->security; 3930 3931 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3932 if (!tsec) 3933 return -ENOMEM; 3934 3935 new->security = tsec; 3936 return 0; 3937 } 3938 3939 /* 3940 * transfer the SELinux data to a blank set of creds 3941 */ 3942 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3943 { 3944 const struct task_security_struct *old_tsec = old->security; 3945 struct task_security_struct *tsec = new->security; 3946 3947 *tsec = *old_tsec; 3948 } 3949 3950 /* 3951 * set the security data for a kernel service 3952 * - all the creation contexts are set to unlabelled 3953 */ 3954 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3955 { 3956 struct task_security_struct *tsec = new->security; 3957 u32 sid = current_sid(); 3958 int ret; 3959 3960 ret = avc_has_perm(&selinux_state, 3961 sid, secid, 3962 SECCLASS_KERNEL_SERVICE, 3963 KERNEL_SERVICE__USE_AS_OVERRIDE, 3964 NULL); 3965 if (ret == 0) { 3966 tsec->sid = secid; 3967 tsec->create_sid = 0; 3968 tsec->keycreate_sid = 0; 3969 tsec->sockcreate_sid = 0; 3970 } 3971 return ret; 3972 } 3973 3974 /* 3975 * set the file creation context in a security record to the same as the 3976 * objective context of the specified inode 3977 */ 3978 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3979 { 3980 struct inode_security_struct *isec = inode_security(inode); 3981 struct task_security_struct *tsec = new->security; 3982 u32 sid = current_sid(); 3983 int ret; 3984 3985 ret = avc_has_perm(&selinux_state, 3986 sid, isec->sid, 3987 SECCLASS_KERNEL_SERVICE, 3988 KERNEL_SERVICE__CREATE_FILES_AS, 3989 NULL); 3990 3991 if (ret == 0) 3992 tsec->create_sid = isec->sid; 3993 return ret; 3994 } 3995 3996 static int selinux_kernel_module_request(char *kmod_name) 3997 { 3998 struct common_audit_data ad; 3999 4000 ad.type = LSM_AUDIT_DATA_KMOD; 4001 ad.u.kmod_name = kmod_name; 4002 4003 return avc_has_perm(&selinux_state, 4004 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, 4005 SYSTEM__MODULE_REQUEST, &ad); 4006 } 4007 4008 static int selinux_kernel_module_from_file(struct file *file) 4009 { 4010 struct common_audit_data ad; 4011 struct inode_security_struct *isec; 4012 struct file_security_struct *fsec; 4013 u32 sid = current_sid(); 4014 int rc; 4015 4016 /* init_module */ 4017 if (file == NULL) 4018 return avc_has_perm(&selinux_state, 4019 sid, sid, SECCLASS_SYSTEM, 4020 SYSTEM__MODULE_LOAD, NULL); 4021 4022 /* finit_module */ 4023 4024 ad.type = LSM_AUDIT_DATA_FILE; 4025 ad.u.file = file; 4026 4027 fsec = file->f_security; 4028 if (sid != fsec->sid) { 4029 rc = avc_has_perm(&selinux_state, 4030 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 4031 if (rc) 4032 return rc; 4033 } 4034 4035 isec = inode_security(file_inode(file)); 4036 return avc_has_perm(&selinux_state, 4037 sid, isec->sid, SECCLASS_SYSTEM, 4038 SYSTEM__MODULE_LOAD, &ad); 4039 } 4040 4041 static int selinux_kernel_read_file(struct file *file, 4042 enum kernel_read_file_id id) 4043 { 4044 int rc = 0; 4045 4046 switch (id) { 4047 case READING_MODULE: 4048 rc = selinux_kernel_module_from_file(file); 4049 break; 4050 default: 4051 break; 4052 } 4053 4054 return rc; 4055 } 4056 4057 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 4058 { 4059 return avc_has_perm(&selinux_state, 4060 current_sid(), task_sid(p), SECCLASS_PROCESS, 4061 PROCESS__SETPGID, NULL); 4062 } 4063 4064 static int selinux_task_getpgid(struct task_struct *p) 4065 { 4066 return avc_has_perm(&selinux_state, 4067 current_sid(), task_sid(p), SECCLASS_PROCESS, 4068 PROCESS__GETPGID, NULL); 4069 } 4070 4071 static int selinux_task_getsid(struct task_struct *p) 4072 { 4073 return avc_has_perm(&selinux_state, 4074 current_sid(), task_sid(p), SECCLASS_PROCESS, 4075 PROCESS__GETSESSION, NULL); 4076 } 4077 4078 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 4079 { 4080 *secid = task_sid(p); 4081 } 4082 4083 static int selinux_task_setnice(struct task_struct *p, int nice) 4084 { 4085 return avc_has_perm(&selinux_state, 4086 current_sid(), task_sid(p), SECCLASS_PROCESS, 4087 PROCESS__SETSCHED, NULL); 4088 } 4089 4090 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 4091 { 4092 return avc_has_perm(&selinux_state, 4093 current_sid(), task_sid(p), SECCLASS_PROCESS, 4094 PROCESS__SETSCHED, NULL); 4095 } 4096 4097 static int selinux_task_getioprio(struct task_struct *p) 4098 { 4099 return avc_has_perm(&selinux_state, 4100 current_sid(), task_sid(p), SECCLASS_PROCESS, 4101 PROCESS__GETSCHED, NULL); 4102 } 4103 4104 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, 4105 unsigned int flags) 4106 { 4107 u32 av = 0; 4108 4109 if (!flags) 4110 return 0; 4111 if (flags & LSM_PRLIMIT_WRITE) 4112 av |= PROCESS__SETRLIMIT; 4113 if (flags & LSM_PRLIMIT_READ) 4114 av |= PROCESS__GETRLIMIT; 4115 return avc_has_perm(&selinux_state, 4116 cred_sid(cred), cred_sid(tcred), 4117 SECCLASS_PROCESS, av, NULL); 4118 } 4119 4120 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 4121 struct rlimit *new_rlim) 4122 { 4123 struct rlimit *old_rlim = p->signal->rlim + resource; 4124 4125 /* Control the ability to change the hard limit (whether 4126 lowering or raising it), so that the hard limit can 4127 later be used as a safe reset point for the soft limit 4128 upon context transitions. See selinux_bprm_committing_creds. */ 4129 if (old_rlim->rlim_max != new_rlim->rlim_max) 4130 return avc_has_perm(&selinux_state, 4131 current_sid(), task_sid(p), 4132 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); 4133 4134 return 0; 4135 } 4136 4137 static int selinux_task_setscheduler(struct task_struct *p) 4138 { 4139 return avc_has_perm(&selinux_state, 4140 current_sid(), task_sid(p), SECCLASS_PROCESS, 4141 PROCESS__SETSCHED, NULL); 4142 } 4143 4144 static int selinux_task_getscheduler(struct task_struct *p) 4145 { 4146 return avc_has_perm(&selinux_state, 4147 current_sid(), task_sid(p), SECCLASS_PROCESS, 4148 PROCESS__GETSCHED, NULL); 4149 } 4150 4151 static int selinux_task_movememory(struct task_struct *p) 4152 { 4153 return avc_has_perm(&selinux_state, 4154 current_sid(), task_sid(p), SECCLASS_PROCESS, 4155 PROCESS__SETSCHED, NULL); 4156 } 4157 4158 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 4159 int sig, u32 secid) 4160 { 4161 u32 perm; 4162 4163 if (!sig) 4164 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4165 else 4166 perm = signal_to_av(sig); 4167 if (!secid) 4168 secid = current_sid(); 4169 return avc_has_perm(&selinux_state, 4170 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL); 4171 } 4172 4173 static void selinux_task_to_inode(struct task_struct *p, 4174 struct inode *inode) 4175 { 4176 struct inode_security_struct *isec = inode->i_security; 4177 u32 sid = task_sid(p); 4178 4179 spin_lock(&isec->lock); 4180 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4181 isec->sid = sid; 4182 isec->initialized = LABEL_INITIALIZED; 4183 spin_unlock(&isec->lock); 4184 } 4185 4186 /* Returns error only if unable to parse addresses */ 4187 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4188 struct common_audit_data *ad, u8 *proto) 4189 { 4190 int offset, ihlen, ret = -EINVAL; 4191 struct iphdr _iph, *ih; 4192 4193 offset = skb_network_offset(skb); 4194 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4195 if (ih == NULL) 4196 goto out; 4197 4198 ihlen = ih->ihl * 4; 4199 if (ihlen < sizeof(_iph)) 4200 goto out; 4201 4202 ad->u.net->v4info.saddr = ih->saddr; 4203 ad->u.net->v4info.daddr = ih->daddr; 4204 ret = 0; 4205 4206 if (proto) 4207 *proto = ih->protocol; 4208 4209 switch (ih->protocol) { 4210 case IPPROTO_TCP: { 4211 struct tcphdr _tcph, *th; 4212 4213 if (ntohs(ih->frag_off) & IP_OFFSET) 4214 break; 4215 4216 offset += ihlen; 4217 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4218 if (th == NULL) 4219 break; 4220 4221 ad->u.net->sport = th->source; 4222 ad->u.net->dport = th->dest; 4223 break; 4224 } 4225 4226 case IPPROTO_UDP: { 4227 struct udphdr _udph, *uh; 4228 4229 if (ntohs(ih->frag_off) & IP_OFFSET) 4230 break; 4231 4232 offset += ihlen; 4233 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4234 if (uh == NULL) 4235 break; 4236 4237 ad->u.net->sport = uh->source; 4238 ad->u.net->dport = uh->dest; 4239 break; 4240 } 4241 4242 case IPPROTO_DCCP: { 4243 struct dccp_hdr _dccph, *dh; 4244 4245 if (ntohs(ih->frag_off) & IP_OFFSET) 4246 break; 4247 4248 offset += ihlen; 4249 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4250 if (dh == NULL) 4251 break; 4252 4253 ad->u.net->sport = dh->dccph_sport; 4254 ad->u.net->dport = dh->dccph_dport; 4255 break; 4256 } 4257 4258 #if IS_ENABLED(CONFIG_IP_SCTP) 4259 case IPPROTO_SCTP: { 4260 struct sctphdr _sctph, *sh; 4261 4262 if (ntohs(ih->frag_off) & IP_OFFSET) 4263 break; 4264 4265 offset += ihlen; 4266 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4267 if (sh == NULL) 4268 break; 4269 4270 ad->u.net->sport = sh->source; 4271 ad->u.net->dport = sh->dest; 4272 break; 4273 } 4274 #endif 4275 default: 4276 break; 4277 } 4278 out: 4279 return ret; 4280 } 4281 4282 #if IS_ENABLED(CONFIG_IPV6) 4283 4284 /* Returns error only if unable to parse addresses */ 4285 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4286 struct common_audit_data *ad, u8 *proto) 4287 { 4288 u8 nexthdr; 4289 int ret = -EINVAL, offset; 4290 struct ipv6hdr _ipv6h, *ip6; 4291 __be16 frag_off; 4292 4293 offset = skb_network_offset(skb); 4294 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4295 if (ip6 == NULL) 4296 goto out; 4297 4298 ad->u.net->v6info.saddr = ip6->saddr; 4299 ad->u.net->v6info.daddr = ip6->daddr; 4300 ret = 0; 4301 4302 nexthdr = ip6->nexthdr; 4303 offset += sizeof(_ipv6h); 4304 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4305 if (offset < 0) 4306 goto out; 4307 4308 if (proto) 4309 *proto = nexthdr; 4310 4311 switch (nexthdr) { 4312 case IPPROTO_TCP: { 4313 struct tcphdr _tcph, *th; 4314 4315 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4316 if (th == NULL) 4317 break; 4318 4319 ad->u.net->sport = th->source; 4320 ad->u.net->dport = th->dest; 4321 break; 4322 } 4323 4324 case IPPROTO_UDP: { 4325 struct udphdr _udph, *uh; 4326 4327 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4328 if (uh == NULL) 4329 break; 4330 4331 ad->u.net->sport = uh->source; 4332 ad->u.net->dport = uh->dest; 4333 break; 4334 } 4335 4336 case IPPROTO_DCCP: { 4337 struct dccp_hdr _dccph, *dh; 4338 4339 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4340 if (dh == NULL) 4341 break; 4342 4343 ad->u.net->sport = dh->dccph_sport; 4344 ad->u.net->dport = dh->dccph_dport; 4345 break; 4346 } 4347 4348 #if IS_ENABLED(CONFIG_IP_SCTP) 4349 case IPPROTO_SCTP: { 4350 struct sctphdr _sctph, *sh; 4351 4352 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); 4353 if (sh == NULL) 4354 break; 4355 4356 ad->u.net->sport = sh->source; 4357 ad->u.net->dport = sh->dest; 4358 break; 4359 } 4360 #endif 4361 /* includes fragments */ 4362 default: 4363 break; 4364 } 4365 out: 4366 return ret; 4367 } 4368 4369 #endif /* IPV6 */ 4370 4371 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4372 char **_addrp, int src, u8 *proto) 4373 { 4374 char *addrp; 4375 int ret; 4376 4377 switch (ad->u.net->family) { 4378 case PF_INET: 4379 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4380 if (ret) 4381 goto parse_error; 4382 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4383 &ad->u.net->v4info.daddr); 4384 goto okay; 4385 4386 #if IS_ENABLED(CONFIG_IPV6) 4387 case PF_INET6: 4388 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4389 if (ret) 4390 goto parse_error; 4391 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4392 &ad->u.net->v6info.daddr); 4393 goto okay; 4394 #endif /* IPV6 */ 4395 default: 4396 addrp = NULL; 4397 goto okay; 4398 } 4399 4400 parse_error: 4401 printk(KERN_WARNING 4402 "SELinux: failure in selinux_parse_skb()," 4403 " unable to parse packet\n"); 4404 return ret; 4405 4406 okay: 4407 if (_addrp) 4408 *_addrp = addrp; 4409 return 0; 4410 } 4411 4412 /** 4413 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4414 * @skb: the packet 4415 * @family: protocol family 4416 * @sid: the packet's peer label SID 4417 * 4418 * Description: 4419 * Check the various different forms of network peer labeling and determine 4420 * the peer label/SID for the packet; most of the magic actually occurs in 4421 * the security server function security_net_peersid_cmp(). The function 4422 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4423 * or -EACCES if @sid is invalid due to inconsistencies with the different 4424 * peer labels. 4425 * 4426 */ 4427 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4428 { 4429 int err; 4430 u32 xfrm_sid; 4431 u32 nlbl_sid; 4432 u32 nlbl_type; 4433 4434 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4435 if (unlikely(err)) 4436 return -EACCES; 4437 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4438 if (unlikely(err)) 4439 return -EACCES; 4440 4441 err = security_net_peersid_resolve(&selinux_state, nlbl_sid, 4442 nlbl_type, xfrm_sid, sid); 4443 if (unlikely(err)) { 4444 printk(KERN_WARNING 4445 "SELinux: failure in selinux_skb_peerlbl_sid()," 4446 " unable to determine packet's peer label\n"); 4447 return -EACCES; 4448 } 4449 4450 return 0; 4451 } 4452 4453 /** 4454 * selinux_conn_sid - Determine the child socket label for a connection 4455 * @sk_sid: the parent socket's SID 4456 * @skb_sid: the packet's SID 4457 * @conn_sid: the resulting connection SID 4458 * 4459 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4460 * combined with the MLS information from @skb_sid in order to create 4461 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy 4462 * of @sk_sid. Returns zero on success, negative values on failure. 4463 * 4464 */ 4465 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4466 { 4467 int err = 0; 4468 4469 if (skb_sid != SECSID_NULL) 4470 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid, 4471 conn_sid); 4472 else 4473 *conn_sid = sk_sid; 4474 4475 return err; 4476 } 4477 4478 /* socket security operations */ 4479 4480 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4481 u16 secclass, u32 *socksid) 4482 { 4483 if (tsec->sockcreate_sid > SECSID_NULL) { 4484 *socksid = tsec->sockcreate_sid; 4485 return 0; 4486 } 4487 4488 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid, 4489 secclass, NULL, socksid); 4490 } 4491 4492 static int sock_has_perm(struct sock *sk, u32 perms) 4493 { 4494 struct sk_security_struct *sksec = sk->sk_security; 4495 struct common_audit_data ad; 4496 struct lsm_network_audit net = {0,}; 4497 4498 if (sksec->sid == SECINITSID_KERNEL) 4499 return 0; 4500 4501 ad.type = LSM_AUDIT_DATA_NET; 4502 ad.u.net = &net; 4503 ad.u.net->sk = sk; 4504 4505 return avc_has_perm(&selinux_state, 4506 current_sid(), sksec->sid, sksec->sclass, perms, 4507 &ad); 4508 } 4509 4510 static int selinux_socket_create(int family, int type, 4511 int protocol, int kern) 4512 { 4513 const struct task_security_struct *tsec = current_security(); 4514 u32 newsid; 4515 u16 secclass; 4516 int rc; 4517 4518 if (kern) 4519 return 0; 4520 4521 secclass = socket_type_to_security_class(family, type, protocol); 4522 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4523 if (rc) 4524 return rc; 4525 4526 return avc_has_perm(&selinux_state, 4527 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4528 } 4529 4530 static int selinux_socket_post_create(struct socket *sock, int family, 4531 int type, int protocol, int kern) 4532 { 4533 const struct task_security_struct *tsec = current_security(); 4534 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4535 struct sk_security_struct *sksec; 4536 u16 sclass = socket_type_to_security_class(family, type, protocol); 4537 u32 sid = SECINITSID_KERNEL; 4538 int err = 0; 4539 4540 if (!kern) { 4541 err = socket_sockcreate_sid(tsec, sclass, &sid); 4542 if (err) 4543 return err; 4544 } 4545 4546 isec->sclass = sclass; 4547 isec->sid = sid; 4548 isec->initialized = LABEL_INITIALIZED; 4549 4550 if (sock->sk) { 4551 sksec = sock->sk->sk_security; 4552 sksec->sclass = sclass; 4553 sksec->sid = sid; 4554 /* Allows detection of the first association on this socket */ 4555 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4556 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; 4557 4558 err = selinux_netlbl_socket_post_create(sock->sk, family); 4559 } 4560 4561 return err; 4562 } 4563 4564 /* Range of port numbers used to automatically bind. 4565 Need to determine whether we should perform a name_bind 4566 permission check between the socket and the port number. */ 4567 4568 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4569 { 4570 struct sock *sk = sock->sk; 4571 u16 family; 4572 int err; 4573 4574 err = sock_has_perm(sk, SOCKET__BIND); 4575 if (err) 4576 goto out; 4577 4578 /* If PF_INET or PF_INET6, check name_bind permission for the port. */ 4579 family = sk->sk_family; 4580 if (family == PF_INET || family == PF_INET6) { 4581 char *addrp; 4582 struct sk_security_struct *sksec = sk->sk_security; 4583 struct common_audit_data ad; 4584 struct lsm_network_audit net = {0,}; 4585 struct sockaddr_in *addr4 = NULL; 4586 struct sockaddr_in6 *addr6 = NULL; 4587 unsigned short snum; 4588 u32 sid, node_perm; 4589 4590 /* 4591 * sctp_bindx(3) calls via selinux_sctp_bind_connect() 4592 * that validates multiple binding addresses. Because of this 4593 * need to check address->sa_family as it is possible to have 4594 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4595 */ 4596 switch (address->sa_family) { 4597 case AF_INET: 4598 if (addrlen < sizeof(struct sockaddr_in)) 4599 return -EINVAL; 4600 addr4 = (struct sockaddr_in *)address; 4601 snum = ntohs(addr4->sin_port); 4602 addrp = (char *)&addr4->sin_addr.s_addr; 4603 break; 4604 case AF_INET6: 4605 if (addrlen < SIN6_LEN_RFC2133) 4606 return -EINVAL; 4607 addr6 = (struct sockaddr_in6 *)address; 4608 snum = ntohs(addr6->sin6_port); 4609 addrp = (char *)&addr6->sin6_addr.s6_addr; 4610 break; 4611 default: 4612 /* Note that SCTP services expect -EINVAL, whereas 4613 * others expect -EAFNOSUPPORT. 4614 */ 4615 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4616 return -EINVAL; 4617 else 4618 return -EAFNOSUPPORT; 4619 } 4620 4621 if (snum) { 4622 int low, high; 4623 4624 inet_get_local_port_range(sock_net(sk), &low, &high); 4625 4626 if (snum < max(inet_prot_sock(sock_net(sk)), low) || 4627 snum > high) { 4628 err = sel_netport_sid(sk->sk_protocol, 4629 snum, &sid); 4630 if (err) 4631 goto out; 4632 ad.type = LSM_AUDIT_DATA_NET; 4633 ad.u.net = &net; 4634 ad.u.net->sport = htons(snum); 4635 ad.u.net->family = family; 4636 err = avc_has_perm(&selinux_state, 4637 sksec->sid, sid, 4638 sksec->sclass, 4639 SOCKET__NAME_BIND, &ad); 4640 if (err) 4641 goto out; 4642 } 4643 } 4644 4645 switch (sksec->sclass) { 4646 case SECCLASS_TCP_SOCKET: 4647 node_perm = TCP_SOCKET__NODE_BIND; 4648 break; 4649 4650 case SECCLASS_UDP_SOCKET: 4651 node_perm = UDP_SOCKET__NODE_BIND; 4652 break; 4653 4654 case SECCLASS_DCCP_SOCKET: 4655 node_perm = DCCP_SOCKET__NODE_BIND; 4656 break; 4657 4658 case SECCLASS_SCTP_SOCKET: 4659 node_perm = SCTP_SOCKET__NODE_BIND; 4660 break; 4661 4662 default: 4663 node_perm = RAWIP_SOCKET__NODE_BIND; 4664 break; 4665 } 4666 4667 err = sel_netnode_sid(addrp, family, &sid); 4668 if (err) 4669 goto out; 4670 4671 ad.type = LSM_AUDIT_DATA_NET; 4672 ad.u.net = &net; 4673 ad.u.net->sport = htons(snum); 4674 ad.u.net->family = family; 4675 4676 if (address->sa_family == AF_INET) 4677 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4678 else 4679 ad.u.net->v6info.saddr = addr6->sin6_addr; 4680 4681 err = avc_has_perm(&selinux_state, 4682 sksec->sid, sid, 4683 sksec->sclass, node_perm, &ad); 4684 if (err) 4685 goto out; 4686 } 4687 out: 4688 return err; 4689 } 4690 4691 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) 4692 * and sctp_sendmsg(3) as described in Documentation/security/LSM-sctp.txt 4693 */ 4694 static int selinux_socket_connect_helper(struct socket *sock, 4695 struct sockaddr *address, int addrlen) 4696 { 4697 struct sock *sk = sock->sk; 4698 struct sk_security_struct *sksec = sk->sk_security; 4699 int err; 4700 4701 err = sock_has_perm(sk, SOCKET__CONNECT); 4702 if (err) 4703 return err; 4704 4705 /* 4706 * If a TCP, DCCP or SCTP socket, check name_connect permission 4707 * for the port. 4708 */ 4709 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4710 sksec->sclass == SECCLASS_DCCP_SOCKET || 4711 sksec->sclass == SECCLASS_SCTP_SOCKET) { 4712 struct common_audit_data ad; 4713 struct lsm_network_audit net = {0,}; 4714 struct sockaddr_in *addr4 = NULL; 4715 struct sockaddr_in6 *addr6 = NULL; 4716 unsigned short snum; 4717 u32 sid, perm; 4718 4719 /* sctp_connectx(3) calls via selinux_sctp_bind_connect() 4720 * that validates multiple connect addresses. Because of this 4721 * need to check address->sa_family as it is possible to have 4722 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. 4723 */ 4724 switch (address->sa_family) { 4725 case AF_INET: 4726 addr4 = (struct sockaddr_in *)address; 4727 if (addrlen < sizeof(struct sockaddr_in)) 4728 return -EINVAL; 4729 snum = ntohs(addr4->sin_port); 4730 break; 4731 case AF_INET6: 4732 addr6 = (struct sockaddr_in6 *)address; 4733 if (addrlen < SIN6_LEN_RFC2133) 4734 return -EINVAL; 4735 snum = ntohs(addr6->sin6_port); 4736 break; 4737 default: 4738 /* Note that SCTP services expect -EINVAL, whereas 4739 * others expect -EAFNOSUPPORT. 4740 */ 4741 if (sksec->sclass == SECCLASS_SCTP_SOCKET) 4742 return -EINVAL; 4743 else 4744 return -EAFNOSUPPORT; 4745 } 4746 4747 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4748 if (err) 4749 return err; 4750 4751 switch (sksec->sclass) { 4752 case SECCLASS_TCP_SOCKET: 4753 perm = TCP_SOCKET__NAME_CONNECT; 4754 break; 4755 case SECCLASS_DCCP_SOCKET: 4756 perm = DCCP_SOCKET__NAME_CONNECT; 4757 break; 4758 case SECCLASS_SCTP_SOCKET: 4759 perm = SCTP_SOCKET__NAME_CONNECT; 4760 break; 4761 } 4762 4763 ad.type = LSM_AUDIT_DATA_NET; 4764 ad.u.net = &net; 4765 ad.u.net->dport = htons(snum); 4766 ad.u.net->family = sk->sk_family; 4767 err = avc_has_perm(&selinux_state, 4768 sksec->sid, sid, sksec->sclass, perm, &ad); 4769 if (err) 4770 return err; 4771 } 4772 4773 return 0; 4774 } 4775 4776 /* Supports connect(2), see comments in selinux_socket_connect_helper() */ 4777 static int selinux_socket_connect(struct socket *sock, 4778 struct sockaddr *address, int addrlen) 4779 { 4780 int err; 4781 struct sock *sk = sock->sk; 4782 4783 err = selinux_socket_connect_helper(sock, address, addrlen); 4784 if (err) 4785 return err; 4786 4787 return selinux_netlbl_socket_connect(sk, address); 4788 } 4789 4790 static int selinux_socket_listen(struct socket *sock, int backlog) 4791 { 4792 return sock_has_perm(sock->sk, SOCKET__LISTEN); 4793 } 4794 4795 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4796 { 4797 int err; 4798 struct inode_security_struct *isec; 4799 struct inode_security_struct *newisec; 4800 u16 sclass; 4801 u32 sid; 4802 4803 err = sock_has_perm(sock->sk, SOCKET__ACCEPT); 4804 if (err) 4805 return err; 4806 4807 isec = inode_security_novalidate(SOCK_INODE(sock)); 4808 spin_lock(&isec->lock); 4809 sclass = isec->sclass; 4810 sid = isec->sid; 4811 spin_unlock(&isec->lock); 4812 4813 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4814 newisec->sclass = sclass; 4815 newisec->sid = sid; 4816 newisec->initialized = LABEL_INITIALIZED; 4817 4818 return 0; 4819 } 4820 4821 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4822 int size) 4823 { 4824 return sock_has_perm(sock->sk, SOCKET__WRITE); 4825 } 4826 4827 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4828 int size, int flags) 4829 { 4830 return sock_has_perm(sock->sk, SOCKET__READ); 4831 } 4832 4833 static int selinux_socket_getsockname(struct socket *sock) 4834 { 4835 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4836 } 4837 4838 static int selinux_socket_getpeername(struct socket *sock) 4839 { 4840 return sock_has_perm(sock->sk, SOCKET__GETATTR); 4841 } 4842 4843 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4844 { 4845 int err; 4846 4847 err = sock_has_perm(sock->sk, SOCKET__SETOPT); 4848 if (err) 4849 return err; 4850 4851 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4852 } 4853 4854 static int selinux_socket_getsockopt(struct socket *sock, int level, 4855 int optname) 4856 { 4857 return sock_has_perm(sock->sk, SOCKET__GETOPT); 4858 } 4859 4860 static int selinux_socket_shutdown(struct socket *sock, int how) 4861 { 4862 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); 4863 } 4864 4865 static int selinux_socket_unix_stream_connect(struct sock *sock, 4866 struct sock *other, 4867 struct sock *newsk) 4868 { 4869 struct sk_security_struct *sksec_sock = sock->sk_security; 4870 struct sk_security_struct *sksec_other = other->sk_security; 4871 struct sk_security_struct *sksec_new = newsk->sk_security; 4872 struct common_audit_data ad; 4873 struct lsm_network_audit net = {0,}; 4874 int err; 4875 4876 ad.type = LSM_AUDIT_DATA_NET; 4877 ad.u.net = &net; 4878 ad.u.net->sk = other; 4879 4880 err = avc_has_perm(&selinux_state, 4881 sksec_sock->sid, sksec_other->sid, 4882 sksec_other->sclass, 4883 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4884 if (err) 4885 return err; 4886 4887 /* server child socket */ 4888 sksec_new->peer_sid = sksec_sock->sid; 4889 err = security_sid_mls_copy(&selinux_state, sksec_other->sid, 4890 sksec_sock->sid, &sksec_new->sid); 4891 if (err) 4892 return err; 4893 4894 /* connecting socket */ 4895 sksec_sock->peer_sid = sksec_new->sid; 4896 4897 return 0; 4898 } 4899 4900 static int selinux_socket_unix_may_send(struct socket *sock, 4901 struct socket *other) 4902 { 4903 struct sk_security_struct *ssec = sock->sk->sk_security; 4904 struct sk_security_struct *osec = other->sk->sk_security; 4905 struct common_audit_data ad; 4906 struct lsm_network_audit net = {0,}; 4907 4908 ad.type = LSM_AUDIT_DATA_NET; 4909 ad.u.net = &net; 4910 ad.u.net->sk = other->sk; 4911 4912 return avc_has_perm(&selinux_state, 4913 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4914 &ad); 4915 } 4916 4917 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4918 char *addrp, u16 family, u32 peer_sid, 4919 struct common_audit_data *ad) 4920 { 4921 int err; 4922 u32 if_sid; 4923 u32 node_sid; 4924 4925 err = sel_netif_sid(ns, ifindex, &if_sid); 4926 if (err) 4927 return err; 4928 err = avc_has_perm(&selinux_state, 4929 peer_sid, if_sid, 4930 SECCLASS_NETIF, NETIF__INGRESS, ad); 4931 if (err) 4932 return err; 4933 4934 err = sel_netnode_sid(addrp, family, &node_sid); 4935 if (err) 4936 return err; 4937 return avc_has_perm(&selinux_state, 4938 peer_sid, node_sid, 4939 SECCLASS_NODE, NODE__RECVFROM, ad); 4940 } 4941 4942 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4943 u16 family) 4944 { 4945 int err = 0; 4946 struct sk_security_struct *sksec = sk->sk_security; 4947 u32 sk_sid = sksec->sid; 4948 struct common_audit_data ad; 4949 struct lsm_network_audit net = {0,}; 4950 char *addrp; 4951 4952 ad.type = LSM_AUDIT_DATA_NET; 4953 ad.u.net = &net; 4954 ad.u.net->netif = skb->skb_iif; 4955 ad.u.net->family = family; 4956 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4957 if (err) 4958 return err; 4959 4960 if (selinux_secmark_enabled()) { 4961 err = avc_has_perm(&selinux_state, 4962 sk_sid, skb->secmark, SECCLASS_PACKET, 4963 PACKET__RECV, &ad); 4964 if (err) 4965 return err; 4966 } 4967 4968 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4969 if (err) 4970 return err; 4971 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4972 4973 return err; 4974 } 4975 4976 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4977 { 4978 int err; 4979 struct sk_security_struct *sksec = sk->sk_security; 4980 u16 family = sk->sk_family; 4981 u32 sk_sid = sksec->sid; 4982 struct common_audit_data ad; 4983 struct lsm_network_audit net = {0,}; 4984 char *addrp; 4985 u8 secmark_active; 4986 u8 peerlbl_active; 4987 4988 if (family != PF_INET && family != PF_INET6) 4989 return 0; 4990 4991 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4992 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4993 family = PF_INET; 4994 4995 /* If any sort of compatibility mode is enabled then handoff processing 4996 * to the selinux_sock_rcv_skb_compat() function to deal with the 4997 * special handling. We do this in an attempt to keep this function 4998 * as fast and as clean as possible. */ 4999 if (!selinux_policycap_netpeer()) 5000 return selinux_sock_rcv_skb_compat(sk, skb, family); 5001 5002 secmark_active = selinux_secmark_enabled(); 5003 peerlbl_active = selinux_peerlbl_enabled(); 5004 if (!secmark_active && !peerlbl_active) 5005 return 0; 5006 5007 ad.type = LSM_AUDIT_DATA_NET; 5008 ad.u.net = &net; 5009 ad.u.net->netif = skb->skb_iif; 5010 ad.u.net->family = family; 5011 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 5012 if (err) 5013 return err; 5014 5015 if (peerlbl_active) { 5016 u32 peer_sid; 5017 5018 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 5019 if (err) 5020 return err; 5021 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 5022 addrp, family, peer_sid, &ad); 5023 if (err) { 5024 selinux_netlbl_err(skb, family, err, 0); 5025 return err; 5026 } 5027 err = avc_has_perm(&selinux_state, 5028 sk_sid, peer_sid, SECCLASS_PEER, 5029 PEER__RECV, &ad); 5030 if (err) { 5031 selinux_netlbl_err(skb, family, err, 0); 5032 return err; 5033 } 5034 } 5035 5036 if (secmark_active) { 5037 err = avc_has_perm(&selinux_state, 5038 sk_sid, skb->secmark, SECCLASS_PACKET, 5039 PACKET__RECV, &ad); 5040 if (err) 5041 return err; 5042 } 5043 5044 return err; 5045 } 5046 5047 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 5048 int __user *optlen, unsigned len) 5049 { 5050 int err = 0; 5051 char *scontext; 5052 u32 scontext_len; 5053 struct sk_security_struct *sksec = sock->sk->sk_security; 5054 u32 peer_sid = SECSID_NULL; 5055 5056 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 5057 sksec->sclass == SECCLASS_TCP_SOCKET || 5058 sksec->sclass == SECCLASS_SCTP_SOCKET) 5059 peer_sid = sksec->peer_sid; 5060 if (peer_sid == SECSID_NULL) 5061 return -ENOPROTOOPT; 5062 5063 err = security_sid_to_context(&selinux_state, peer_sid, &scontext, 5064 &scontext_len); 5065 if (err) 5066 return err; 5067 5068 if (scontext_len > len) { 5069 err = -ERANGE; 5070 goto out_len; 5071 } 5072 5073 if (copy_to_user(optval, scontext, scontext_len)) 5074 err = -EFAULT; 5075 5076 out_len: 5077 if (put_user(scontext_len, optlen)) 5078 err = -EFAULT; 5079 kfree(scontext); 5080 return err; 5081 } 5082 5083 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 5084 { 5085 u32 peer_secid = SECSID_NULL; 5086 u16 family; 5087 struct inode_security_struct *isec; 5088 5089 if (skb && skb->protocol == htons(ETH_P_IP)) 5090 family = PF_INET; 5091 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 5092 family = PF_INET6; 5093 else if (sock) 5094 family = sock->sk->sk_family; 5095 else 5096 goto out; 5097 5098 if (sock && family == PF_UNIX) { 5099 isec = inode_security_novalidate(SOCK_INODE(sock)); 5100 peer_secid = isec->sid; 5101 } else if (skb) 5102 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 5103 5104 out: 5105 *secid = peer_secid; 5106 if (peer_secid == SECSID_NULL) 5107 return -EINVAL; 5108 return 0; 5109 } 5110 5111 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 5112 { 5113 struct sk_security_struct *sksec; 5114 5115 sksec = kzalloc(sizeof(*sksec), priority); 5116 if (!sksec) 5117 return -ENOMEM; 5118 5119 sksec->peer_sid = SECINITSID_UNLABELED; 5120 sksec->sid = SECINITSID_UNLABELED; 5121 sksec->sclass = SECCLASS_SOCKET; 5122 selinux_netlbl_sk_security_reset(sksec); 5123 sk->sk_security = sksec; 5124 5125 return 0; 5126 } 5127 5128 static void selinux_sk_free_security(struct sock *sk) 5129 { 5130 struct sk_security_struct *sksec = sk->sk_security; 5131 5132 sk->sk_security = NULL; 5133 selinux_netlbl_sk_security_free(sksec); 5134 kfree(sksec); 5135 } 5136 5137 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 5138 { 5139 struct sk_security_struct *sksec = sk->sk_security; 5140 struct sk_security_struct *newsksec = newsk->sk_security; 5141 5142 newsksec->sid = sksec->sid; 5143 newsksec->peer_sid = sksec->peer_sid; 5144 newsksec->sclass = sksec->sclass; 5145 5146 selinux_netlbl_sk_security_reset(newsksec); 5147 } 5148 5149 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 5150 { 5151 if (!sk) 5152 *secid = SECINITSID_ANY_SOCKET; 5153 else { 5154 struct sk_security_struct *sksec = sk->sk_security; 5155 5156 *secid = sksec->sid; 5157 } 5158 } 5159 5160 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 5161 { 5162 struct inode_security_struct *isec = 5163 inode_security_novalidate(SOCK_INODE(parent)); 5164 struct sk_security_struct *sksec = sk->sk_security; 5165 5166 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 5167 sk->sk_family == PF_UNIX) 5168 isec->sid = sksec->sid; 5169 sksec->sclass = isec->sclass; 5170 } 5171 5172 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming 5173 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association 5174 * already present). 5175 */ 5176 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep, 5177 struct sk_buff *skb) 5178 { 5179 struct sk_security_struct *sksec = ep->base.sk->sk_security; 5180 struct common_audit_data ad; 5181 struct lsm_network_audit net = {0,}; 5182 u8 peerlbl_active; 5183 u32 peer_sid = SECINITSID_UNLABELED; 5184 u32 conn_sid; 5185 int err = 0; 5186 5187 if (!selinux_policycap_extsockclass()) 5188 return 0; 5189 5190 peerlbl_active = selinux_peerlbl_enabled(); 5191 5192 if (peerlbl_active) { 5193 /* This will return peer_sid = SECSID_NULL if there are 5194 * no peer labels, see security_net_peersid_resolve(). 5195 */ 5196 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family, 5197 &peer_sid); 5198 if (err) 5199 return err; 5200 5201 if (peer_sid == SECSID_NULL) 5202 peer_sid = SECINITSID_UNLABELED; 5203 } 5204 5205 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { 5206 sksec->sctp_assoc_state = SCTP_ASSOC_SET; 5207 5208 /* Here as first association on socket. As the peer SID 5209 * was allowed by peer recv (and the netif/node checks), 5210 * then it is approved by policy and used as the primary 5211 * peer SID for getpeercon(3). 5212 */ 5213 sksec->peer_sid = peer_sid; 5214 } else if (sksec->peer_sid != peer_sid) { 5215 /* Other association peer SIDs are checked to enforce 5216 * consistency among the peer SIDs. 5217 */ 5218 ad.type = LSM_AUDIT_DATA_NET; 5219 ad.u.net = &net; 5220 ad.u.net->sk = ep->base.sk; 5221 err = avc_has_perm(&selinux_state, 5222 sksec->peer_sid, peer_sid, sksec->sclass, 5223 SCTP_SOCKET__ASSOCIATION, &ad); 5224 if (err) 5225 return err; 5226 } 5227 5228 /* Compute the MLS component for the connection and store 5229 * the information in ep. This will be used by SCTP TCP type 5230 * sockets and peeled off connections as they cause a new 5231 * socket to be generated. selinux_sctp_sk_clone() will then 5232 * plug this into the new socket. 5233 */ 5234 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid); 5235 if (err) 5236 return err; 5237 5238 ep->secid = conn_sid; 5239 ep->peer_secid = peer_sid; 5240 5241 /* Set any NetLabel labels including CIPSO/CALIPSO options. */ 5242 return selinux_netlbl_sctp_assoc_request(ep, skb); 5243 } 5244 5245 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting 5246 * based on their @optname. 5247 */ 5248 static int selinux_sctp_bind_connect(struct sock *sk, int optname, 5249 struct sockaddr *address, 5250 int addrlen) 5251 { 5252 int len, err = 0, walk_size = 0; 5253 void *addr_buf; 5254 struct sockaddr *addr; 5255 struct socket *sock; 5256 5257 if (!selinux_policycap_extsockclass()) 5258 return 0; 5259 5260 /* Process one or more addresses that may be IPv4 or IPv6 */ 5261 sock = sk->sk_socket; 5262 addr_buf = address; 5263 5264 while (walk_size < addrlen) { 5265 addr = addr_buf; 5266 switch (addr->sa_family) { 5267 case AF_INET: 5268 len = sizeof(struct sockaddr_in); 5269 break; 5270 case AF_INET6: 5271 len = sizeof(struct sockaddr_in6); 5272 break; 5273 default: 5274 return -EAFNOSUPPORT; 5275 } 5276 5277 err = -EINVAL; 5278 switch (optname) { 5279 /* Bind checks */ 5280 case SCTP_PRIMARY_ADDR: 5281 case SCTP_SET_PEER_PRIMARY_ADDR: 5282 case SCTP_SOCKOPT_BINDX_ADD: 5283 err = selinux_socket_bind(sock, addr, len); 5284 break; 5285 /* Connect checks */ 5286 case SCTP_SOCKOPT_CONNECTX: 5287 case SCTP_PARAM_SET_PRIMARY: 5288 case SCTP_PARAM_ADD_IP: 5289 case SCTP_SENDMSG_CONNECT: 5290 err = selinux_socket_connect_helper(sock, addr, len); 5291 if (err) 5292 return err; 5293 5294 /* As selinux_sctp_bind_connect() is called by the 5295 * SCTP protocol layer, the socket is already locked, 5296 * therefore selinux_netlbl_socket_connect_locked() is 5297 * is called here. The situations handled are: 5298 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), 5299 * whenever a new IP address is added or when a new 5300 * primary address is selected. 5301 * Note that an SCTP connect(2) call happens before 5302 * the SCTP protocol layer and is handled via 5303 * selinux_socket_connect(). 5304 */ 5305 err = selinux_netlbl_socket_connect_locked(sk, addr); 5306 break; 5307 } 5308 5309 if (err) 5310 return err; 5311 5312 addr_buf += len; 5313 walk_size += len; 5314 } 5315 5316 return 0; 5317 } 5318 5319 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ 5320 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk, 5321 struct sock *newsk) 5322 { 5323 struct sk_security_struct *sksec = sk->sk_security; 5324 struct sk_security_struct *newsksec = newsk->sk_security; 5325 5326 /* If policy does not support SECCLASS_SCTP_SOCKET then call 5327 * the non-sctp clone version. 5328 */ 5329 if (!selinux_policycap_extsockclass()) 5330 return selinux_sk_clone_security(sk, newsk); 5331 5332 newsksec->sid = ep->secid; 5333 newsksec->peer_sid = ep->peer_secid; 5334 newsksec->sclass = sksec->sclass; 5335 selinux_netlbl_sctp_sk_clone(sk, newsk); 5336 } 5337 5338 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 5339 struct request_sock *req) 5340 { 5341 struct sk_security_struct *sksec = sk->sk_security; 5342 int err; 5343 u16 family = req->rsk_ops->family; 5344 u32 connsid; 5345 u32 peersid; 5346 5347 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 5348 if (err) 5349 return err; 5350 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 5351 if (err) 5352 return err; 5353 req->secid = connsid; 5354 req->peer_secid = peersid; 5355 5356 return selinux_netlbl_inet_conn_request(req, family); 5357 } 5358 5359 static void selinux_inet_csk_clone(struct sock *newsk, 5360 const struct request_sock *req) 5361 { 5362 struct sk_security_struct *newsksec = newsk->sk_security; 5363 5364 newsksec->sid = req->secid; 5365 newsksec->peer_sid = req->peer_secid; 5366 /* NOTE: Ideally, we should also get the isec->sid for the 5367 new socket in sync, but we don't have the isec available yet. 5368 So we will wait until sock_graft to do it, by which 5369 time it will have been created and available. */ 5370 5371 /* We don't need to take any sort of lock here as we are the only 5372 * thread with access to newsksec */ 5373 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 5374 } 5375 5376 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 5377 { 5378 u16 family = sk->sk_family; 5379 struct sk_security_struct *sksec = sk->sk_security; 5380 5381 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 5382 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 5383 family = PF_INET; 5384 5385 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 5386 } 5387 5388 static int selinux_secmark_relabel_packet(u32 sid) 5389 { 5390 const struct task_security_struct *__tsec; 5391 u32 tsid; 5392 5393 __tsec = current_security(); 5394 tsid = __tsec->sid; 5395 5396 return avc_has_perm(&selinux_state, 5397 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, 5398 NULL); 5399 } 5400 5401 static void selinux_secmark_refcount_inc(void) 5402 { 5403 atomic_inc(&selinux_secmark_refcount); 5404 } 5405 5406 static void selinux_secmark_refcount_dec(void) 5407 { 5408 atomic_dec(&selinux_secmark_refcount); 5409 } 5410 5411 static void selinux_req_classify_flow(const struct request_sock *req, 5412 struct flowi *fl) 5413 { 5414 fl->flowi_secid = req->secid; 5415 } 5416 5417 static int selinux_tun_dev_alloc_security(void **security) 5418 { 5419 struct tun_security_struct *tunsec; 5420 5421 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5422 if (!tunsec) 5423 return -ENOMEM; 5424 tunsec->sid = current_sid(); 5425 5426 *security = tunsec; 5427 return 0; 5428 } 5429 5430 static void selinux_tun_dev_free_security(void *security) 5431 { 5432 kfree(security); 5433 } 5434 5435 static int selinux_tun_dev_create(void) 5436 { 5437 u32 sid = current_sid(); 5438 5439 /* we aren't taking into account the "sockcreate" SID since the socket 5440 * that is being created here is not a socket in the traditional sense, 5441 * instead it is a private sock, accessible only to the kernel, and 5442 * representing a wide range of network traffic spanning multiple 5443 * connections unlike traditional sockets - check the TUN driver to 5444 * get a better understanding of why this socket is special */ 5445 5446 return avc_has_perm(&selinux_state, 5447 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5448 NULL); 5449 } 5450 5451 static int selinux_tun_dev_attach_queue(void *security) 5452 { 5453 struct tun_security_struct *tunsec = security; 5454 5455 return avc_has_perm(&selinux_state, 5456 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5457 TUN_SOCKET__ATTACH_QUEUE, NULL); 5458 } 5459 5460 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5461 { 5462 struct tun_security_struct *tunsec = security; 5463 struct sk_security_struct *sksec = sk->sk_security; 5464 5465 /* we don't currently perform any NetLabel based labeling here and it 5466 * isn't clear that we would want to do so anyway; while we could apply 5467 * labeling without the support of the TUN user the resulting labeled 5468 * traffic from the other end of the connection would almost certainly 5469 * cause confusion to the TUN user that had no idea network labeling 5470 * protocols were being used */ 5471 5472 sksec->sid = tunsec->sid; 5473 sksec->sclass = SECCLASS_TUN_SOCKET; 5474 5475 return 0; 5476 } 5477 5478 static int selinux_tun_dev_open(void *security) 5479 { 5480 struct tun_security_struct *tunsec = security; 5481 u32 sid = current_sid(); 5482 int err; 5483 5484 err = avc_has_perm(&selinux_state, 5485 sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5486 TUN_SOCKET__RELABELFROM, NULL); 5487 if (err) 5488 return err; 5489 err = avc_has_perm(&selinux_state, 5490 sid, sid, SECCLASS_TUN_SOCKET, 5491 TUN_SOCKET__RELABELTO, NULL); 5492 if (err) 5493 return err; 5494 tunsec->sid = sid; 5495 5496 return 0; 5497 } 5498 5499 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 5500 { 5501 int err = 0; 5502 u32 perm; 5503 struct nlmsghdr *nlh; 5504 struct sk_security_struct *sksec = sk->sk_security; 5505 5506 if (skb->len < NLMSG_HDRLEN) { 5507 err = -EINVAL; 5508 goto out; 5509 } 5510 nlh = nlmsg_hdr(skb); 5511 5512 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); 5513 if (err) { 5514 if (err == -EINVAL) { 5515 pr_warn_ratelimited("SELinux: unrecognized netlink" 5516 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5517 " pig=%d comm=%s\n", 5518 sk->sk_protocol, nlh->nlmsg_type, 5519 secclass_map[sksec->sclass - 1].name, 5520 task_pid_nr(current), current->comm); 5521 if (!enforcing_enabled(&selinux_state) || 5522 security_get_allow_unknown(&selinux_state)) 5523 err = 0; 5524 } 5525 5526 /* Ignore */ 5527 if (err == -ENOENT) 5528 err = 0; 5529 goto out; 5530 } 5531 5532 err = sock_has_perm(sk, perm); 5533 out: 5534 return err; 5535 } 5536 5537 #ifdef CONFIG_NETFILTER 5538 5539 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5540 const struct net_device *indev, 5541 u16 family) 5542 { 5543 int err; 5544 char *addrp; 5545 u32 peer_sid; 5546 struct common_audit_data ad; 5547 struct lsm_network_audit net = {0,}; 5548 u8 secmark_active; 5549 u8 netlbl_active; 5550 u8 peerlbl_active; 5551 5552 if (!selinux_policycap_netpeer()) 5553 return NF_ACCEPT; 5554 5555 secmark_active = selinux_secmark_enabled(); 5556 netlbl_active = netlbl_enabled(); 5557 peerlbl_active = selinux_peerlbl_enabled(); 5558 if (!secmark_active && !peerlbl_active) 5559 return NF_ACCEPT; 5560 5561 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5562 return NF_DROP; 5563 5564 ad.type = LSM_AUDIT_DATA_NET; 5565 ad.u.net = &net; 5566 ad.u.net->netif = indev->ifindex; 5567 ad.u.net->family = family; 5568 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5569 return NF_DROP; 5570 5571 if (peerlbl_active) { 5572 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5573 addrp, family, peer_sid, &ad); 5574 if (err) { 5575 selinux_netlbl_err(skb, family, err, 1); 5576 return NF_DROP; 5577 } 5578 } 5579 5580 if (secmark_active) 5581 if (avc_has_perm(&selinux_state, 5582 peer_sid, skb->secmark, 5583 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5584 return NF_DROP; 5585 5586 if (netlbl_active) 5587 /* we do this in the FORWARD path and not the POST_ROUTING 5588 * path because we want to make sure we apply the necessary 5589 * labeling before IPsec is applied so we can leverage AH 5590 * protection */ 5591 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5592 return NF_DROP; 5593 5594 return NF_ACCEPT; 5595 } 5596 5597 static unsigned int selinux_ipv4_forward(void *priv, 5598 struct sk_buff *skb, 5599 const struct nf_hook_state *state) 5600 { 5601 return selinux_ip_forward(skb, state->in, PF_INET); 5602 } 5603 5604 #if IS_ENABLED(CONFIG_IPV6) 5605 static unsigned int selinux_ipv6_forward(void *priv, 5606 struct sk_buff *skb, 5607 const struct nf_hook_state *state) 5608 { 5609 return selinux_ip_forward(skb, state->in, PF_INET6); 5610 } 5611 #endif /* IPV6 */ 5612 5613 static unsigned int selinux_ip_output(struct sk_buff *skb, 5614 u16 family) 5615 { 5616 struct sock *sk; 5617 u32 sid; 5618 5619 if (!netlbl_enabled()) 5620 return NF_ACCEPT; 5621 5622 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5623 * because we want to make sure we apply the necessary labeling 5624 * before IPsec is applied so we can leverage AH protection */ 5625 sk = skb->sk; 5626 if (sk) { 5627 struct sk_security_struct *sksec; 5628 5629 if (sk_listener(sk)) 5630 /* if the socket is the listening state then this 5631 * packet is a SYN-ACK packet which means it needs to 5632 * be labeled based on the connection/request_sock and 5633 * not the parent socket. unfortunately, we can't 5634 * lookup the request_sock yet as it isn't queued on 5635 * the parent socket until after the SYN-ACK is sent. 5636 * the "solution" is to simply pass the packet as-is 5637 * as any IP option based labeling should be copied 5638 * from the initial connection request (in the IP 5639 * layer). it is far from ideal, but until we get a 5640 * security label in the packet itself this is the 5641 * best we can do. */ 5642 return NF_ACCEPT; 5643 5644 /* standard practice, label using the parent socket */ 5645 sksec = sk->sk_security; 5646 sid = sksec->sid; 5647 } else 5648 sid = SECINITSID_KERNEL; 5649 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5650 return NF_DROP; 5651 5652 return NF_ACCEPT; 5653 } 5654 5655 static unsigned int selinux_ipv4_output(void *priv, 5656 struct sk_buff *skb, 5657 const struct nf_hook_state *state) 5658 { 5659 return selinux_ip_output(skb, PF_INET); 5660 } 5661 5662 #if IS_ENABLED(CONFIG_IPV6) 5663 static unsigned int selinux_ipv6_output(void *priv, 5664 struct sk_buff *skb, 5665 const struct nf_hook_state *state) 5666 { 5667 return selinux_ip_output(skb, PF_INET6); 5668 } 5669 #endif /* IPV6 */ 5670 5671 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5672 int ifindex, 5673 u16 family) 5674 { 5675 struct sock *sk = skb_to_full_sk(skb); 5676 struct sk_security_struct *sksec; 5677 struct common_audit_data ad; 5678 struct lsm_network_audit net = {0,}; 5679 char *addrp; 5680 u8 proto; 5681 5682 if (sk == NULL) 5683 return NF_ACCEPT; 5684 sksec = sk->sk_security; 5685 5686 ad.type = LSM_AUDIT_DATA_NET; 5687 ad.u.net = &net; 5688 ad.u.net->netif = ifindex; 5689 ad.u.net->family = family; 5690 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5691 return NF_DROP; 5692 5693 if (selinux_secmark_enabled()) 5694 if (avc_has_perm(&selinux_state, 5695 sksec->sid, skb->secmark, 5696 SECCLASS_PACKET, PACKET__SEND, &ad)) 5697 return NF_DROP_ERR(-ECONNREFUSED); 5698 5699 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5700 return NF_DROP_ERR(-ECONNREFUSED); 5701 5702 return NF_ACCEPT; 5703 } 5704 5705 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5706 const struct net_device *outdev, 5707 u16 family) 5708 { 5709 u32 secmark_perm; 5710 u32 peer_sid; 5711 int ifindex = outdev->ifindex; 5712 struct sock *sk; 5713 struct common_audit_data ad; 5714 struct lsm_network_audit net = {0,}; 5715 char *addrp; 5716 u8 secmark_active; 5717 u8 peerlbl_active; 5718 5719 /* If any sort of compatibility mode is enabled then handoff processing 5720 * to the selinux_ip_postroute_compat() function to deal with the 5721 * special handling. We do this in an attempt to keep this function 5722 * as fast and as clean as possible. */ 5723 if (!selinux_policycap_netpeer()) 5724 return selinux_ip_postroute_compat(skb, ifindex, family); 5725 5726 secmark_active = selinux_secmark_enabled(); 5727 peerlbl_active = selinux_peerlbl_enabled(); 5728 if (!secmark_active && !peerlbl_active) 5729 return NF_ACCEPT; 5730 5731 sk = skb_to_full_sk(skb); 5732 5733 #ifdef CONFIG_XFRM 5734 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5735 * packet transformation so allow the packet to pass without any checks 5736 * since we'll have another chance to perform access control checks 5737 * when the packet is on it's final way out. 5738 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5739 * is NULL, in this case go ahead and apply access control. 5740 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5741 * TCP listening state we cannot wait until the XFRM processing 5742 * is done as we will miss out on the SA label if we do; 5743 * unfortunately, this means more work, but it is only once per 5744 * connection. */ 5745 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5746 !(sk && sk_listener(sk))) 5747 return NF_ACCEPT; 5748 #endif 5749 5750 if (sk == NULL) { 5751 /* Without an associated socket the packet is either coming 5752 * from the kernel or it is being forwarded; check the packet 5753 * to determine which and if the packet is being forwarded 5754 * query the packet directly to determine the security label. */ 5755 if (skb->skb_iif) { 5756 secmark_perm = PACKET__FORWARD_OUT; 5757 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5758 return NF_DROP; 5759 } else { 5760 secmark_perm = PACKET__SEND; 5761 peer_sid = SECINITSID_KERNEL; 5762 } 5763 } else if (sk_listener(sk)) { 5764 /* Locally generated packet but the associated socket is in the 5765 * listening state which means this is a SYN-ACK packet. In 5766 * this particular case the correct security label is assigned 5767 * to the connection/request_sock but unfortunately we can't 5768 * query the request_sock as it isn't queued on the parent 5769 * socket until after the SYN-ACK packet is sent; the only 5770 * viable choice is to regenerate the label like we do in 5771 * selinux_inet_conn_request(). See also selinux_ip_output() 5772 * for similar problems. */ 5773 u32 skb_sid; 5774 struct sk_security_struct *sksec; 5775 5776 sksec = sk->sk_security; 5777 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5778 return NF_DROP; 5779 /* At this point, if the returned skb peerlbl is SECSID_NULL 5780 * and the packet has been through at least one XFRM 5781 * transformation then we must be dealing with the "final" 5782 * form of labeled IPsec packet; since we've already applied 5783 * all of our access controls on this packet we can safely 5784 * pass the packet. */ 5785 if (skb_sid == SECSID_NULL) { 5786 switch (family) { 5787 case PF_INET: 5788 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5789 return NF_ACCEPT; 5790 break; 5791 case PF_INET6: 5792 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5793 return NF_ACCEPT; 5794 break; 5795 default: 5796 return NF_DROP_ERR(-ECONNREFUSED); 5797 } 5798 } 5799 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5800 return NF_DROP; 5801 secmark_perm = PACKET__SEND; 5802 } else { 5803 /* Locally generated packet, fetch the security label from the 5804 * associated socket. */ 5805 struct sk_security_struct *sksec = sk->sk_security; 5806 peer_sid = sksec->sid; 5807 secmark_perm = PACKET__SEND; 5808 } 5809 5810 ad.type = LSM_AUDIT_DATA_NET; 5811 ad.u.net = &net; 5812 ad.u.net->netif = ifindex; 5813 ad.u.net->family = family; 5814 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5815 return NF_DROP; 5816 5817 if (secmark_active) 5818 if (avc_has_perm(&selinux_state, 5819 peer_sid, skb->secmark, 5820 SECCLASS_PACKET, secmark_perm, &ad)) 5821 return NF_DROP_ERR(-ECONNREFUSED); 5822 5823 if (peerlbl_active) { 5824 u32 if_sid; 5825 u32 node_sid; 5826 5827 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5828 return NF_DROP; 5829 if (avc_has_perm(&selinux_state, 5830 peer_sid, if_sid, 5831 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5832 return NF_DROP_ERR(-ECONNREFUSED); 5833 5834 if (sel_netnode_sid(addrp, family, &node_sid)) 5835 return NF_DROP; 5836 if (avc_has_perm(&selinux_state, 5837 peer_sid, node_sid, 5838 SECCLASS_NODE, NODE__SENDTO, &ad)) 5839 return NF_DROP_ERR(-ECONNREFUSED); 5840 } 5841 5842 return NF_ACCEPT; 5843 } 5844 5845 static unsigned int selinux_ipv4_postroute(void *priv, 5846 struct sk_buff *skb, 5847 const struct nf_hook_state *state) 5848 { 5849 return selinux_ip_postroute(skb, state->out, PF_INET); 5850 } 5851 5852 #if IS_ENABLED(CONFIG_IPV6) 5853 static unsigned int selinux_ipv6_postroute(void *priv, 5854 struct sk_buff *skb, 5855 const struct nf_hook_state *state) 5856 { 5857 return selinux_ip_postroute(skb, state->out, PF_INET6); 5858 } 5859 #endif /* IPV6 */ 5860 5861 #endif /* CONFIG_NETFILTER */ 5862 5863 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5864 { 5865 return selinux_nlmsg_perm(sk, skb); 5866 } 5867 5868 static int ipc_alloc_security(struct kern_ipc_perm *perm, 5869 u16 sclass) 5870 { 5871 struct ipc_security_struct *isec; 5872 5873 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 5874 if (!isec) 5875 return -ENOMEM; 5876 5877 isec->sclass = sclass; 5878 isec->sid = current_sid(); 5879 perm->security = isec; 5880 5881 return 0; 5882 } 5883 5884 static void ipc_free_security(struct kern_ipc_perm *perm) 5885 { 5886 struct ipc_security_struct *isec = perm->security; 5887 perm->security = NULL; 5888 kfree(isec); 5889 } 5890 5891 static int msg_msg_alloc_security(struct msg_msg *msg) 5892 { 5893 struct msg_security_struct *msec; 5894 5895 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 5896 if (!msec) 5897 return -ENOMEM; 5898 5899 msec->sid = SECINITSID_UNLABELED; 5900 msg->security = msec; 5901 5902 return 0; 5903 } 5904 5905 static void msg_msg_free_security(struct msg_msg *msg) 5906 { 5907 struct msg_security_struct *msec = msg->security; 5908 5909 msg->security = NULL; 5910 kfree(msec); 5911 } 5912 5913 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5914 u32 perms) 5915 { 5916 struct ipc_security_struct *isec; 5917 struct common_audit_data ad; 5918 u32 sid = current_sid(); 5919 5920 isec = ipc_perms->security; 5921 5922 ad.type = LSM_AUDIT_DATA_IPC; 5923 ad.u.ipc_id = ipc_perms->key; 5924 5925 return avc_has_perm(&selinux_state, 5926 sid, isec->sid, isec->sclass, perms, &ad); 5927 } 5928 5929 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5930 { 5931 return msg_msg_alloc_security(msg); 5932 } 5933 5934 static void selinux_msg_msg_free_security(struct msg_msg *msg) 5935 { 5936 msg_msg_free_security(msg); 5937 } 5938 5939 /* message queue security operations */ 5940 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 5941 { 5942 struct ipc_security_struct *isec; 5943 struct common_audit_data ad; 5944 u32 sid = current_sid(); 5945 int rc; 5946 5947 rc = ipc_alloc_security(&msq->q_perm, SECCLASS_MSGQ); 5948 if (rc) 5949 return rc; 5950 5951 isec = msq->q_perm.security; 5952 5953 ad.type = LSM_AUDIT_DATA_IPC; 5954 ad.u.ipc_id = msq->q_perm.key; 5955 5956 rc = avc_has_perm(&selinux_state, 5957 sid, isec->sid, SECCLASS_MSGQ, 5958 MSGQ__CREATE, &ad); 5959 if (rc) { 5960 ipc_free_security(&msq->q_perm); 5961 return rc; 5962 } 5963 return 0; 5964 } 5965 5966 static void selinux_msg_queue_free_security(struct msg_queue *msq) 5967 { 5968 ipc_free_security(&msq->q_perm); 5969 } 5970 5971 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 5972 { 5973 struct ipc_security_struct *isec; 5974 struct common_audit_data ad; 5975 u32 sid = current_sid(); 5976 5977 isec = msq->q_perm.security; 5978 5979 ad.type = LSM_AUDIT_DATA_IPC; 5980 ad.u.ipc_id = msq->q_perm.key; 5981 5982 return avc_has_perm(&selinux_state, 5983 sid, isec->sid, SECCLASS_MSGQ, 5984 MSGQ__ASSOCIATE, &ad); 5985 } 5986 5987 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 5988 { 5989 int err; 5990 int perms; 5991 5992 switch (cmd) { 5993 case IPC_INFO: 5994 case MSG_INFO: 5995 /* No specific object, just general system-wide information. */ 5996 return avc_has_perm(&selinux_state, 5997 current_sid(), SECINITSID_KERNEL, 5998 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 5999 case IPC_STAT: 6000 case MSG_STAT: 6001 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 6002 break; 6003 case IPC_SET: 6004 perms = MSGQ__SETATTR; 6005 break; 6006 case IPC_RMID: 6007 perms = MSGQ__DESTROY; 6008 break; 6009 default: 6010 return 0; 6011 } 6012 6013 err = ipc_has_perm(&msq->q_perm, perms); 6014 return err; 6015 } 6016 6017 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 6018 { 6019 struct ipc_security_struct *isec; 6020 struct msg_security_struct *msec; 6021 struct common_audit_data ad; 6022 u32 sid = current_sid(); 6023 int rc; 6024 6025 isec = msq->q_perm.security; 6026 msec = msg->security; 6027 6028 /* 6029 * First time through, need to assign label to the message 6030 */ 6031 if (msec->sid == SECINITSID_UNLABELED) { 6032 /* 6033 * Compute new sid based on current process and 6034 * message queue this message will be stored in 6035 */ 6036 rc = security_transition_sid(&selinux_state, sid, isec->sid, 6037 SECCLASS_MSG, NULL, &msec->sid); 6038 if (rc) 6039 return rc; 6040 } 6041 6042 ad.type = LSM_AUDIT_DATA_IPC; 6043 ad.u.ipc_id = msq->q_perm.key; 6044 6045 /* Can this process write to the queue? */ 6046 rc = avc_has_perm(&selinux_state, 6047 sid, isec->sid, SECCLASS_MSGQ, 6048 MSGQ__WRITE, &ad); 6049 if (!rc) 6050 /* Can this process send the message */ 6051 rc = avc_has_perm(&selinux_state, 6052 sid, msec->sid, SECCLASS_MSG, 6053 MSG__SEND, &ad); 6054 if (!rc) 6055 /* Can the message be put in the queue? */ 6056 rc = avc_has_perm(&selinux_state, 6057 msec->sid, isec->sid, SECCLASS_MSGQ, 6058 MSGQ__ENQUEUE, &ad); 6059 6060 return rc; 6061 } 6062 6063 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 6064 struct task_struct *target, 6065 long type, int mode) 6066 { 6067 struct ipc_security_struct *isec; 6068 struct msg_security_struct *msec; 6069 struct common_audit_data ad; 6070 u32 sid = task_sid(target); 6071 int rc; 6072 6073 isec = msq->q_perm.security; 6074 msec = msg->security; 6075 6076 ad.type = LSM_AUDIT_DATA_IPC; 6077 ad.u.ipc_id = msq->q_perm.key; 6078 6079 rc = avc_has_perm(&selinux_state, 6080 sid, isec->sid, 6081 SECCLASS_MSGQ, MSGQ__READ, &ad); 6082 if (!rc) 6083 rc = avc_has_perm(&selinux_state, 6084 sid, msec->sid, 6085 SECCLASS_MSG, MSG__RECEIVE, &ad); 6086 return rc; 6087 } 6088 6089 /* Shared Memory security operations */ 6090 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 6091 { 6092 struct ipc_security_struct *isec; 6093 struct common_audit_data ad; 6094 u32 sid = current_sid(); 6095 int rc; 6096 6097 rc = ipc_alloc_security(&shp->shm_perm, SECCLASS_SHM); 6098 if (rc) 6099 return rc; 6100 6101 isec = shp->shm_perm.security; 6102 6103 ad.type = LSM_AUDIT_DATA_IPC; 6104 ad.u.ipc_id = shp->shm_perm.key; 6105 6106 rc = avc_has_perm(&selinux_state, 6107 sid, isec->sid, SECCLASS_SHM, 6108 SHM__CREATE, &ad); 6109 if (rc) { 6110 ipc_free_security(&shp->shm_perm); 6111 return rc; 6112 } 6113 return 0; 6114 } 6115 6116 static void selinux_shm_free_security(struct shmid_kernel *shp) 6117 { 6118 ipc_free_security(&shp->shm_perm); 6119 } 6120 6121 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 6122 { 6123 struct ipc_security_struct *isec; 6124 struct common_audit_data ad; 6125 u32 sid = current_sid(); 6126 6127 isec = shp->shm_perm.security; 6128 6129 ad.type = LSM_AUDIT_DATA_IPC; 6130 ad.u.ipc_id = shp->shm_perm.key; 6131 6132 return avc_has_perm(&selinux_state, 6133 sid, isec->sid, SECCLASS_SHM, 6134 SHM__ASSOCIATE, &ad); 6135 } 6136 6137 /* Note, at this point, shp is locked down */ 6138 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 6139 { 6140 int perms; 6141 int err; 6142 6143 switch (cmd) { 6144 case IPC_INFO: 6145 case SHM_INFO: 6146 /* No specific object, just general system-wide information. */ 6147 return avc_has_perm(&selinux_state, 6148 current_sid(), SECINITSID_KERNEL, 6149 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6150 case IPC_STAT: 6151 case SHM_STAT: 6152 perms = SHM__GETATTR | SHM__ASSOCIATE; 6153 break; 6154 case IPC_SET: 6155 perms = SHM__SETATTR; 6156 break; 6157 case SHM_LOCK: 6158 case SHM_UNLOCK: 6159 perms = SHM__LOCK; 6160 break; 6161 case IPC_RMID: 6162 perms = SHM__DESTROY; 6163 break; 6164 default: 6165 return 0; 6166 } 6167 6168 err = ipc_has_perm(&shp->shm_perm, perms); 6169 return err; 6170 } 6171 6172 static int selinux_shm_shmat(struct shmid_kernel *shp, 6173 char __user *shmaddr, int shmflg) 6174 { 6175 u32 perms; 6176 6177 if (shmflg & SHM_RDONLY) 6178 perms = SHM__READ; 6179 else 6180 perms = SHM__READ | SHM__WRITE; 6181 6182 return ipc_has_perm(&shp->shm_perm, perms); 6183 } 6184 6185 /* Semaphore security operations */ 6186 static int selinux_sem_alloc_security(struct sem_array *sma) 6187 { 6188 struct ipc_security_struct *isec; 6189 struct common_audit_data ad; 6190 u32 sid = current_sid(); 6191 int rc; 6192 6193 rc = ipc_alloc_security(&sma->sem_perm, SECCLASS_SEM); 6194 if (rc) 6195 return rc; 6196 6197 isec = sma->sem_perm.security; 6198 6199 ad.type = LSM_AUDIT_DATA_IPC; 6200 ad.u.ipc_id = sma->sem_perm.key; 6201 6202 rc = avc_has_perm(&selinux_state, 6203 sid, isec->sid, SECCLASS_SEM, 6204 SEM__CREATE, &ad); 6205 if (rc) { 6206 ipc_free_security(&sma->sem_perm); 6207 return rc; 6208 } 6209 return 0; 6210 } 6211 6212 static void selinux_sem_free_security(struct sem_array *sma) 6213 { 6214 ipc_free_security(&sma->sem_perm); 6215 } 6216 6217 static int selinux_sem_associate(struct sem_array *sma, int semflg) 6218 { 6219 struct ipc_security_struct *isec; 6220 struct common_audit_data ad; 6221 u32 sid = current_sid(); 6222 6223 isec = sma->sem_perm.security; 6224 6225 ad.type = LSM_AUDIT_DATA_IPC; 6226 ad.u.ipc_id = sma->sem_perm.key; 6227 6228 return avc_has_perm(&selinux_state, 6229 sid, isec->sid, SECCLASS_SEM, 6230 SEM__ASSOCIATE, &ad); 6231 } 6232 6233 /* Note, at this point, sma is locked down */ 6234 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 6235 { 6236 int err; 6237 u32 perms; 6238 6239 switch (cmd) { 6240 case IPC_INFO: 6241 case SEM_INFO: 6242 /* No specific object, just general system-wide information. */ 6243 return avc_has_perm(&selinux_state, 6244 current_sid(), SECINITSID_KERNEL, 6245 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); 6246 case GETPID: 6247 case GETNCNT: 6248 case GETZCNT: 6249 perms = SEM__GETATTR; 6250 break; 6251 case GETVAL: 6252 case GETALL: 6253 perms = SEM__READ; 6254 break; 6255 case SETVAL: 6256 case SETALL: 6257 perms = SEM__WRITE; 6258 break; 6259 case IPC_RMID: 6260 perms = SEM__DESTROY; 6261 break; 6262 case IPC_SET: 6263 perms = SEM__SETATTR; 6264 break; 6265 case IPC_STAT: 6266 case SEM_STAT: 6267 perms = SEM__GETATTR | SEM__ASSOCIATE; 6268 break; 6269 default: 6270 return 0; 6271 } 6272 6273 err = ipc_has_perm(&sma->sem_perm, perms); 6274 return err; 6275 } 6276 6277 static int selinux_sem_semop(struct sem_array *sma, 6278 struct sembuf *sops, unsigned nsops, int alter) 6279 { 6280 u32 perms; 6281 6282 if (alter) 6283 perms = SEM__READ | SEM__WRITE; 6284 else 6285 perms = SEM__READ; 6286 6287 return ipc_has_perm(&sma->sem_perm, perms); 6288 } 6289 6290 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 6291 { 6292 u32 av = 0; 6293 6294 av = 0; 6295 if (flag & S_IRUGO) 6296 av |= IPC__UNIX_READ; 6297 if (flag & S_IWUGO) 6298 av |= IPC__UNIX_WRITE; 6299 6300 if (av == 0) 6301 return 0; 6302 6303 return ipc_has_perm(ipcp, av); 6304 } 6305 6306 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 6307 { 6308 struct ipc_security_struct *isec = ipcp->security; 6309 *secid = isec->sid; 6310 } 6311 6312 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 6313 { 6314 if (inode) 6315 inode_doinit_with_dentry(inode, dentry); 6316 } 6317 6318 static int selinux_getprocattr(struct task_struct *p, 6319 char *name, char **value) 6320 { 6321 const struct task_security_struct *__tsec; 6322 u32 sid; 6323 int error; 6324 unsigned len; 6325 6326 rcu_read_lock(); 6327 __tsec = __task_cred(p)->security; 6328 6329 if (current != p) { 6330 error = avc_has_perm(&selinux_state, 6331 current_sid(), __tsec->sid, 6332 SECCLASS_PROCESS, PROCESS__GETATTR, NULL); 6333 if (error) 6334 goto bad; 6335 } 6336 6337 if (!strcmp(name, "current")) 6338 sid = __tsec->sid; 6339 else if (!strcmp(name, "prev")) 6340 sid = __tsec->osid; 6341 else if (!strcmp(name, "exec")) 6342 sid = __tsec->exec_sid; 6343 else if (!strcmp(name, "fscreate")) 6344 sid = __tsec->create_sid; 6345 else if (!strcmp(name, "keycreate")) 6346 sid = __tsec->keycreate_sid; 6347 else if (!strcmp(name, "sockcreate")) 6348 sid = __tsec->sockcreate_sid; 6349 else { 6350 error = -EINVAL; 6351 goto bad; 6352 } 6353 rcu_read_unlock(); 6354 6355 if (!sid) 6356 return 0; 6357 6358 error = security_sid_to_context(&selinux_state, sid, value, &len); 6359 if (error) 6360 return error; 6361 return len; 6362 6363 bad: 6364 rcu_read_unlock(); 6365 return error; 6366 } 6367 6368 static int selinux_setprocattr(const char *name, void *value, size_t size) 6369 { 6370 struct task_security_struct *tsec; 6371 struct cred *new; 6372 u32 mysid = current_sid(), sid = 0, ptsid; 6373 int error; 6374 char *str = value; 6375 6376 /* 6377 * Basic control over ability to set these attributes at all. 6378 */ 6379 if (!strcmp(name, "exec")) 6380 error = avc_has_perm(&selinux_state, 6381 mysid, mysid, SECCLASS_PROCESS, 6382 PROCESS__SETEXEC, NULL); 6383 else if (!strcmp(name, "fscreate")) 6384 error = avc_has_perm(&selinux_state, 6385 mysid, mysid, SECCLASS_PROCESS, 6386 PROCESS__SETFSCREATE, NULL); 6387 else if (!strcmp(name, "keycreate")) 6388 error = avc_has_perm(&selinux_state, 6389 mysid, mysid, SECCLASS_PROCESS, 6390 PROCESS__SETKEYCREATE, NULL); 6391 else if (!strcmp(name, "sockcreate")) 6392 error = avc_has_perm(&selinux_state, 6393 mysid, mysid, SECCLASS_PROCESS, 6394 PROCESS__SETSOCKCREATE, NULL); 6395 else if (!strcmp(name, "current")) 6396 error = avc_has_perm(&selinux_state, 6397 mysid, mysid, SECCLASS_PROCESS, 6398 PROCESS__SETCURRENT, NULL); 6399 else 6400 error = -EINVAL; 6401 if (error) 6402 return error; 6403 6404 /* Obtain a SID for the context, if one was specified. */ 6405 if (size && str[0] && str[0] != '\n') { 6406 if (str[size-1] == '\n') { 6407 str[size-1] = 0; 6408 size--; 6409 } 6410 error = security_context_to_sid(&selinux_state, value, size, 6411 &sid, GFP_KERNEL); 6412 if (error == -EINVAL && !strcmp(name, "fscreate")) { 6413 if (!has_cap_mac_admin(true)) { 6414 struct audit_buffer *ab; 6415 size_t audit_size; 6416 6417 /* We strip a nul only if it is at the end, otherwise the 6418 * context contains a nul and we should audit that */ 6419 if (str[size - 1] == '\0') 6420 audit_size = size - 1; 6421 else 6422 audit_size = size; 6423 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); 6424 audit_log_format(ab, "op=fscreate invalid_context="); 6425 audit_log_n_untrustedstring(ab, value, audit_size); 6426 audit_log_end(ab); 6427 6428 return error; 6429 } 6430 error = security_context_to_sid_force( 6431 &selinux_state, 6432 value, size, &sid); 6433 } 6434 if (error) 6435 return error; 6436 } 6437 6438 new = prepare_creds(); 6439 if (!new) 6440 return -ENOMEM; 6441 6442 /* Permission checking based on the specified context is 6443 performed during the actual operation (execve, 6444 open/mkdir/...), when we know the full context of the 6445 operation. See selinux_bprm_set_creds for the execve 6446 checks and may_create for the file creation checks. The 6447 operation will then fail if the context is not permitted. */ 6448 tsec = new->security; 6449 if (!strcmp(name, "exec")) { 6450 tsec->exec_sid = sid; 6451 } else if (!strcmp(name, "fscreate")) { 6452 tsec->create_sid = sid; 6453 } else if (!strcmp(name, "keycreate")) { 6454 error = avc_has_perm(&selinux_state, 6455 mysid, sid, SECCLASS_KEY, KEY__CREATE, 6456 NULL); 6457 if (error) 6458 goto abort_change; 6459 tsec->keycreate_sid = sid; 6460 } else if (!strcmp(name, "sockcreate")) { 6461 tsec->sockcreate_sid = sid; 6462 } else if (!strcmp(name, "current")) { 6463 error = -EINVAL; 6464 if (sid == 0) 6465 goto abort_change; 6466 6467 /* Only allow single threaded processes to change context */ 6468 error = -EPERM; 6469 if (!current_is_single_threaded()) { 6470 error = security_bounded_transition(&selinux_state, 6471 tsec->sid, sid); 6472 if (error) 6473 goto abort_change; 6474 } 6475 6476 /* Check permissions for the transition. */ 6477 error = avc_has_perm(&selinux_state, 6478 tsec->sid, sid, SECCLASS_PROCESS, 6479 PROCESS__DYNTRANSITION, NULL); 6480 if (error) 6481 goto abort_change; 6482 6483 /* Check for ptracing, and update the task SID if ok. 6484 Otherwise, leave SID unchanged and fail. */ 6485 ptsid = ptrace_parent_sid(); 6486 if (ptsid != 0) { 6487 error = avc_has_perm(&selinux_state, 6488 ptsid, sid, SECCLASS_PROCESS, 6489 PROCESS__PTRACE, NULL); 6490 if (error) 6491 goto abort_change; 6492 } 6493 6494 tsec->sid = sid; 6495 } else { 6496 error = -EINVAL; 6497 goto abort_change; 6498 } 6499 6500 commit_creds(new); 6501 return size; 6502 6503 abort_change: 6504 abort_creds(new); 6505 return error; 6506 } 6507 6508 static int selinux_ismaclabel(const char *name) 6509 { 6510 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6511 } 6512 6513 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6514 { 6515 return security_sid_to_context(&selinux_state, secid, 6516 secdata, seclen); 6517 } 6518 6519 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6520 { 6521 return security_context_to_sid(&selinux_state, secdata, seclen, 6522 secid, GFP_KERNEL); 6523 } 6524 6525 static void selinux_release_secctx(char *secdata, u32 seclen) 6526 { 6527 kfree(secdata); 6528 } 6529 6530 static void selinux_inode_invalidate_secctx(struct inode *inode) 6531 { 6532 struct inode_security_struct *isec = inode->i_security; 6533 6534 spin_lock(&isec->lock); 6535 isec->initialized = LABEL_INVALID; 6536 spin_unlock(&isec->lock); 6537 } 6538 6539 /* 6540 * called with inode->i_mutex locked 6541 */ 6542 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6543 { 6544 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); 6545 } 6546 6547 /* 6548 * called with inode->i_mutex locked 6549 */ 6550 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6551 { 6552 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 6553 } 6554 6555 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6556 { 6557 int len = 0; 6558 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 6559 ctx, true); 6560 if (len < 0) 6561 return len; 6562 *ctxlen = len; 6563 return 0; 6564 } 6565 #ifdef CONFIG_KEYS 6566 6567 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6568 unsigned long flags) 6569 { 6570 const struct task_security_struct *tsec; 6571 struct key_security_struct *ksec; 6572 6573 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6574 if (!ksec) 6575 return -ENOMEM; 6576 6577 tsec = cred->security; 6578 if (tsec->keycreate_sid) 6579 ksec->sid = tsec->keycreate_sid; 6580 else 6581 ksec->sid = tsec->sid; 6582 6583 k->security = ksec; 6584 return 0; 6585 } 6586 6587 static void selinux_key_free(struct key *k) 6588 { 6589 struct key_security_struct *ksec = k->security; 6590 6591 k->security = NULL; 6592 kfree(ksec); 6593 } 6594 6595 static int selinux_key_permission(key_ref_t key_ref, 6596 const struct cred *cred, 6597 unsigned perm) 6598 { 6599 struct key *key; 6600 struct key_security_struct *ksec; 6601 u32 sid; 6602 6603 /* if no specific permissions are requested, we skip the 6604 permission check. No serious, additional covert channels 6605 appear to be created. */ 6606 if (perm == 0) 6607 return 0; 6608 6609 sid = cred_sid(cred); 6610 6611 key = key_ref_to_ptr(key_ref); 6612 ksec = key->security; 6613 6614 return avc_has_perm(&selinux_state, 6615 sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6616 } 6617 6618 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6619 { 6620 struct key_security_struct *ksec = key->security; 6621 char *context = NULL; 6622 unsigned len; 6623 int rc; 6624 6625 rc = security_sid_to_context(&selinux_state, ksec->sid, 6626 &context, &len); 6627 if (!rc) 6628 rc = len; 6629 *_buffer = context; 6630 return rc; 6631 } 6632 #endif 6633 6634 #ifdef CONFIG_SECURITY_INFINIBAND 6635 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) 6636 { 6637 struct common_audit_data ad; 6638 int err; 6639 u32 sid = 0; 6640 struct ib_security_struct *sec = ib_sec; 6641 struct lsm_ibpkey_audit ibpkey; 6642 6643 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); 6644 if (err) 6645 return err; 6646 6647 ad.type = LSM_AUDIT_DATA_IBPKEY; 6648 ibpkey.subnet_prefix = subnet_prefix; 6649 ibpkey.pkey = pkey_val; 6650 ad.u.ibpkey = &ibpkey; 6651 return avc_has_perm(&selinux_state, 6652 sec->sid, sid, 6653 SECCLASS_INFINIBAND_PKEY, 6654 INFINIBAND_PKEY__ACCESS, &ad); 6655 } 6656 6657 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, 6658 u8 port_num) 6659 { 6660 struct common_audit_data ad; 6661 int err; 6662 u32 sid = 0; 6663 struct ib_security_struct *sec = ib_sec; 6664 struct lsm_ibendport_audit ibendport; 6665 6666 err = security_ib_endport_sid(&selinux_state, dev_name, port_num, 6667 &sid); 6668 6669 if (err) 6670 return err; 6671 6672 ad.type = LSM_AUDIT_DATA_IBENDPORT; 6673 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name)); 6674 ibendport.port = port_num; 6675 ad.u.ibendport = &ibendport; 6676 return avc_has_perm(&selinux_state, 6677 sec->sid, sid, 6678 SECCLASS_INFINIBAND_ENDPORT, 6679 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); 6680 } 6681 6682 static int selinux_ib_alloc_security(void **ib_sec) 6683 { 6684 struct ib_security_struct *sec; 6685 6686 sec = kzalloc(sizeof(*sec), GFP_KERNEL); 6687 if (!sec) 6688 return -ENOMEM; 6689 sec->sid = current_sid(); 6690 6691 *ib_sec = sec; 6692 return 0; 6693 } 6694 6695 static void selinux_ib_free_security(void *ib_sec) 6696 { 6697 kfree(ib_sec); 6698 } 6699 #endif 6700 6701 #ifdef CONFIG_BPF_SYSCALL 6702 static int selinux_bpf(int cmd, union bpf_attr *attr, 6703 unsigned int size) 6704 { 6705 u32 sid = current_sid(); 6706 int ret; 6707 6708 switch (cmd) { 6709 case BPF_MAP_CREATE: 6710 ret = avc_has_perm(&selinux_state, 6711 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, 6712 NULL); 6713 break; 6714 case BPF_PROG_LOAD: 6715 ret = avc_has_perm(&selinux_state, 6716 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, 6717 NULL); 6718 break; 6719 default: 6720 ret = 0; 6721 break; 6722 } 6723 6724 return ret; 6725 } 6726 6727 static u32 bpf_map_fmode_to_av(fmode_t fmode) 6728 { 6729 u32 av = 0; 6730 6731 if (fmode & FMODE_READ) 6732 av |= BPF__MAP_READ; 6733 if (fmode & FMODE_WRITE) 6734 av |= BPF__MAP_WRITE; 6735 return av; 6736 } 6737 6738 /* This function will check the file pass through unix socket or binder to see 6739 * if it is a bpf related object. And apply correspinding checks on the bpf 6740 * object based on the type. The bpf maps and programs, not like other files and 6741 * socket, are using a shared anonymous inode inside the kernel as their inode. 6742 * So checking that inode cannot identify if the process have privilege to 6743 * access the bpf object and that's why we have to add this additional check in 6744 * selinux_file_receive and selinux_binder_transfer_files. 6745 */ 6746 static int bpf_fd_pass(struct file *file, u32 sid) 6747 { 6748 struct bpf_security_struct *bpfsec; 6749 struct bpf_prog *prog; 6750 struct bpf_map *map; 6751 int ret; 6752 6753 if (file->f_op == &bpf_map_fops) { 6754 map = file->private_data; 6755 bpfsec = map->security; 6756 ret = avc_has_perm(&selinux_state, 6757 sid, bpfsec->sid, SECCLASS_BPF, 6758 bpf_map_fmode_to_av(file->f_mode), NULL); 6759 if (ret) 6760 return ret; 6761 } else if (file->f_op == &bpf_prog_fops) { 6762 prog = file->private_data; 6763 bpfsec = prog->aux->security; 6764 ret = avc_has_perm(&selinux_state, 6765 sid, bpfsec->sid, SECCLASS_BPF, 6766 BPF__PROG_RUN, NULL); 6767 if (ret) 6768 return ret; 6769 } 6770 return 0; 6771 } 6772 6773 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) 6774 { 6775 u32 sid = current_sid(); 6776 struct bpf_security_struct *bpfsec; 6777 6778 bpfsec = map->security; 6779 return avc_has_perm(&selinux_state, 6780 sid, bpfsec->sid, SECCLASS_BPF, 6781 bpf_map_fmode_to_av(fmode), NULL); 6782 } 6783 6784 static int selinux_bpf_prog(struct bpf_prog *prog) 6785 { 6786 u32 sid = current_sid(); 6787 struct bpf_security_struct *bpfsec; 6788 6789 bpfsec = prog->aux->security; 6790 return avc_has_perm(&selinux_state, 6791 sid, bpfsec->sid, SECCLASS_BPF, 6792 BPF__PROG_RUN, NULL); 6793 } 6794 6795 static int selinux_bpf_map_alloc(struct bpf_map *map) 6796 { 6797 struct bpf_security_struct *bpfsec; 6798 6799 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6800 if (!bpfsec) 6801 return -ENOMEM; 6802 6803 bpfsec->sid = current_sid(); 6804 map->security = bpfsec; 6805 6806 return 0; 6807 } 6808 6809 static void selinux_bpf_map_free(struct bpf_map *map) 6810 { 6811 struct bpf_security_struct *bpfsec = map->security; 6812 6813 map->security = NULL; 6814 kfree(bpfsec); 6815 } 6816 6817 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) 6818 { 6819 struct bpf_security_struct *bpfsec; 6820 6821 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); 6822 if (!bpfsec) 6823 return -ENOMEM; 6824 6825 bpfsec->sid = current_sid(); 6826 aux->security = bpfsec; 6827 6828 return 0; 6829 } 6830 6831 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) 6832 { 6833 struct bpf_security_struct *bpfsec = aux->security; 6834 6835 aux->security = NULL; 6836 kfree(bpfsec); 6837 } 6838 #endif 6839 6840 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { 6841 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6842 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6843 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6844 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6845 6846 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6847 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6848 LSM_HOOK_INIT(capget, selinux_capget), 6849 LSM_HOOK_INIT(capset, selinux_capset), 6850 LSM_HOOK_INIT(capable, selinux_capable), 6851 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6852 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6853 LSM_HOOK_INIT(syslog, selinux_syslog), 6854 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6855 6856 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6857 6858 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds), 6859 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6860 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6861 6862 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 6863 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), 6864 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data), 6865 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6866 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6867 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6868 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6869 LSM_HOOK_INIT(sb_mount, selinux_mount), 6870 LSM_HOOK_INIT(sb_umount, selinux_umount), 6871 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6872 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6873 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str), 6874 6875 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6876 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 6877 6878 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 6879 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 6880 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 6881 LSM_HOOK_INIT(inode_create, selinux_inode_create), 6882 LSM_HOOK_INIT(inode_link, selinux_inode_link), 6883 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 6884 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 6885 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 6886 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 6887 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 6888 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 6889 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 6890 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 6891 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 6892 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 6893 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 6894 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 6895 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 6896 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 6897 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 6898 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 6899 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 6900 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 6901 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 6902 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 6903 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 6904 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 6905 6906 LSM_HOOK_INIT(file_permission, selinux_file_permission), 6907 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 6908 LSM_HOOK_INIT(file_free_security, selinux_file_free_security), 6909 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 6910 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 6911 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 6912 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 6913 LSM_HOOK_INIT(file_lock, selinux_file_lock), 6914 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 6915 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 6916 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 6917 LSM_HOOK_INIT(file_receive, selinux_file_receive), 6918 6919 LSM_HOOK_INIT(file_open, selinux_file_open), 6920 6921 LSM_HOOK_INIT(task_alloc, selinux_task_alloc), 6922 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank), 6923 LSM_HOOK_INIT(cred_free, selinux_cred_free), 6924 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 6925 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 6926 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 6927 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 6928 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 6929 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 6930 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 6931 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 6932 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 6933 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), 6934 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 6935 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 6936 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 6937 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), 6938 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 6939 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 6940 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 6941 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 6942 LSM_HOOK_INIT(task_kill, selinux_task_kill), 6943 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 6944 6945 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 6946 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 6947 6948 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 6949 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security), 6950 6951 LSM_HOOK_INIT(msg_queue_alloc_security, 6952 selinux_msg_queue_alloc_security), 6953 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security), 6954 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 6955 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 6956 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 6957 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 6958 6959 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 6960 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security), 6961 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 6962 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 6963 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 6964 6965 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 6966 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security), 6967 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 6968 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 6969 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 6970 6971 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 6972 6973 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 6974 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 6975 6976 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 6977 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 6978 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 6979 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 6980 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 6981 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 6982 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 6983 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 6984 6985 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 6986 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 6987 6988 LSM_HOOK_INIT(socket_create, selinux_socket_create), 6989 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 6990 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 6991 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 6992 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 6993 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 6994 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 6995 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 6996 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 6997 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 6998 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 6999 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 7000 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 7001 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 7002 LSM_HOOK_INIT(socket_getpeersec_stream, 7003 selinux_socket_getpeersec_stream), 7004 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 7005 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 7006 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 7007 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 7008 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 7009 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 7010 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), 7011 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), 7012 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), 7013 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 7014 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 7015 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 7016 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 7017 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 7018 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 7019 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 7020 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 7021 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 7022 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 7023 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 7024 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 7025 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 7026 #ifdef CONFIG_SECURITY_INFINIBAND 7027 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), 7028 LSM_HOOK_INIT(ib_endport_manage_subnet, 7029 selinux_ib_endport_manage_subnet), 7030 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), 7031 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), 7032 #endif 7033 #ifdef CONFIG_SECURITY_NETWORK_XFRM 7034 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 7035 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 7036 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 7037 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 7038 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 7039 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 7040 selinux_xfrm_state_alloc_acquire), 7041 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 7042 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 7043 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 7044 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 7045 selinux_xfrm_state_pol_flow_match), 7046 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 7047 #endif 7048 7049 #ifdef CONFIG_KEYS 7050 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 7051 LSM_HOOK_INIT(key_free, selinux_key_free), 7052 LSM_HOOK_INIT(key_permission, selinux_key_permission), 7053 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 7054 #endif 7055 7056 #ifdef CONFIG_AUDIT 7057 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 7058 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 7059 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 7060 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 7061 #endif 7062 7063 #ifdef CONFIG_BPF_SYSCALL 7064 LSM_HOOK_INIT(bpf, selinux_bpf), 7065 LSM_HOOK_INIT(bpf_map, selinux_bpf_map), 7066 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), 7067 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), 7068 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), 7069 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), 7070 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), 7071 #endif 7072 }; 7073 7074 static __init int selinux_init(void) 7075 { 7076 if (!security_module_enable("selinux")) { 7077 selinux_enabled = 0; 7078 return 0; 7079 } 7080 7081 if (!selinux_enabled) { 7082 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 7083 return 0; 7084 } 7085 7086 printk(KERN_INFO "SELinux: Initializing.\n"); 7087 7088 memset(&selinux_state, 0, sizeof(selinux_state)); 7089 enforcing_set(&selinux_state, selinux_enforcing_boot); 7090 selinux_state.checkreqprot = selinux_checkreqprot_boot; 7091 selinux_ss_init(&selinux_state.ss); 7092 selinux_avc_init(&selinux_state.avc); 7093 7094 /* Set the security state for the initial task. */ 7095 cred_init_security(); 7096 7097 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 7098 7099 sel_inode_cache = kmem_cache_create("selinux_inode_security", 7100 sizeof(struct inode_security_struct), 7101 0, SLAB_PANIC, NULL); 7102 file_security_cache = kmem_cache_create("selinux_file_security", 7103 sizeof(struct file_security_struct), 7104 0, SLAB_PANIC, NULL); 7105 avc_init(); 7106 7107 avtab_cache_init(); 7108 7109 ebitmap_cache_init(); 7110 7111 hashtab_cache_init(); 7112 7113 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); 7114 7115 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 7116 panic("SELinux: Unable to register AVC netcache callback\n"); 7117 7118 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) 7119 panic("SELinux: Unable to register AVC LSM notifier callback\n"); 7120 7121 if (selinux_enforcing_boot) 7122 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 7123 else 7124 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 7125 7126 return 0; 7127 } 7128 7129 static void delayed_superblock_init(struct super_block *sb, void *unused) 7130 { 7131 superblock_doinit(sb, NULL); 7132 } 7133 7134 void selinux_complete_init(void) 7135 { 7136 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 7137 7138 /* Set up any superblocks initialized prior to the policy load. */ 7139 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 7140 iterate_supers(delayed_superblock_init, NULL); 7141 } 7142 7143 /* SELinux requires early initialization in order to label 7144 all processes and objects when they are created. */ 7145 security_initcall(selinux_init); 7146 7147 #if defined(CONFIG_NETFILTER) 7148 7149 static const struct nf_hook_ops selinux_nf_ops[] = { 7150 { 7151 .hook = selinux_ipv4_postroute, 7152 .pf = NFPROTO_IPV4, 7153 .hooknum = NF_INET_POST_ROUTING, 7154 .priority = NF_IP_PRI_SELINUX_LAST, 7155 }, 7156 { 7157 .hook = selinux_ipv4_forward, 7158 .pf = NFPROTO_IPV4, 7159 .hooknum = NF_INET_FORWARD, 7160 .priority = NF_IP_PRI_SELINUX_FIRST, 7161 }, 7162 { 7163 .hook = selinux_ipv4_output, 7164 .pf = NFPROTO_IPV4, 7165 .hooknum = NF_INET_LOCAL_OUT, 7166 .priority = NF_IP_PRI_SELINUX_FIRST, 7167 }, 7168 #if IS_ENABLED(CONFIG_IPV6) 7169 { 7170 .hook = selinux_ipv6_postroute, 7171 .pf = NFPROTO_IPV6, 7172 .hooknum = NF_INET_POST_ROUTING, 7173 .priority = NF_IP6_PRI_SELINUX_LAST, 7174 }, 7175 { 7176 .hook = selinux_ipv6_forward, 7177 .pf = NFPROTO_IPV6, 7178 .hooknum = NF_INET_FORWARD, 7179 .priority = NF_IP6_PRI_SELINUX_FIRST, 7180 }, 7181 { 7182 .hook = selinux_ipv6_output, 7183 .pf = NFPROTO_IPV6, 7184 .hooknum = NF_INET_LOCAL_OUT, 7185 .priority = NF_IP6_PRI_SELINUX_FIRST, 7186 }, 7187 #endif /* IPV6 */ 7188 }; 7189 7190 static int __net_init selinux_nf_register(struct net *net) 7191 { 7192 return nf_register_net_hooks(net, selinux_nf_ops, 7193 ARRAY_SIZE(selinux_nf_ops)); 7194 } 7195 7196 static void __net_exit selinux_nf_unregister(struct net *net) 7197 { 7198 nf_unregister_net_hooks(net, selinux_nf_ops, 7199 ARRAY_SIZE(selinux_nf_ops)); 7200 } 7201 7202 static struct pernet_operations selinux_net_ops = { 7203 .init = selinux_nf_register, 7204 .exit = selinux_nf_unregister, 7205 }; 7206 7207 static int __init selinux_nf_ip_init(void) 7208 { 7209 int err; 7210 7211 if (!selinux_enabled) 7212 return 0; 7213 7214 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 7215 7216 err = register_pernet_subsys(&selinux_net_ops); 7217 if (err) 7218 panic("SELinux: register_pernet_subsys: error %d\n", err); 7219 7220 return 0; 7221 } 7222 __initcall(selinux_nf_ip_init); 7223 7224 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7225 static void selinux_nf_ip_exit(void) 7226 { 7227 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 7228 7229 unregister_pernet_subsys(&selinux_net_ops); 7230 } 7231 #endif 7232 7233 #else /* CONFIG_NETFILTER */ 7234 7235 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7236 #define selinux_nf_ip_exit() 7237 #endif 7238 7239 #endif /* CONFIG_NETFILTER */ 7240 7241 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 7242 int selinux_disable(struct selinux_state *state) 7243 { 7244 if (state->initialized) { 7245 /* Not permitted after initial policy load. */ 7246 return -EINVAL; 7247 } 7248 7249 if (state->disabled) { 7250 /* Only do this once. */ 7251 return -EINVAL; 7252 } 7253 7254 state->disabled = 1; 7255 7256 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 7257 7258 selinux_enabled = 0; 7259 7260 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 7261 7262 /* Try to destroy the avc node cache */ 7263 avc_disable(); 7264 7265 /* Unregister netfilter hooks. */ 7266 selinux_nf_ip_exit(); 7267 7268 /* Unregister selinuxfs. */ 7269 exit_sel_fs(); 7270 7271 return 0; 7272 } 7273 #endif 7274