1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AppArmor security module 4 * 5 * This file contains AppArmor functions for unpacking policy loaded from 6 * userspace. 7 * 8 * Copyright (C) 1998-2008 Novell/SUSE 9 * Copyright 2009-2010 Canonical Ltd. 10 * 11 * AppArmor uses a serialized binary format for loading policy. To find 12 * policy format documentation see Documentation/admin-guide/LSM/apparmor.rst 13 * All policy is validated before it is used. 14 */ 15 16 #include <linux/unaligned.h> 17 #include <kunit/visibility.h> 18 #include <linux/ctype.h> 19 #include <linux/errno.h> 20 #include <linux/zstd.h> 21 22 #include "include/apparmor.h" 23 #include "include/audit.h" 24 #include "include/cred.h" 25 #include "include/crypto.h" 26 #include "include/file.h" 27 #include "include/match.h" 28 #include "include/path.h" 29 #include "include/policy.h" 30 #include "include/policy_unpack.h" 31 #include "include/policy_compat.h" 32 #include "include/signal.h" 33 34 /* audit callback for unpack fields */ 35 static void audit_cb(struct audit_buffer *ab, void *va) 36 { 37 struct common_audit_data *sa = va; 38 struct apparmor_audit_data *ad = aad(sa); 39 40 if (ad->iface.ns) { 41 audit_log_format(ab, " ns="); 42 audit_log_untrustedstring(ab, ad->iface.ns); 43 } 44 if (ad->name) { 45 audit_log_format(ab, " name="); 46 audit_log_untrustedstring(ab, ad->name); 47 } 48 if (ad->iface.pos) 49 audit_log_format(ab, " offset=%ld", ad->iface.pos); 50 } 51 52 /** 53 * audit_iface - do audit message for policy unpacking/load/replace/remove 54 * @new: profile if it has been allocated (MAYBE NULL) 55 * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL) 56 * @name: name of the profile being manipulated (MAYBE NULL) 57 * @info: any extra info about the failure (MAYBE NULL) 58 * @e: buffer position info 59 * @error: error code 60 * 61 * Returns: %0 or error 62 */ 63 static int audit_iface(struct aa_profile *new, const char *ns_name, 64 const char *name, const char *info, struct aa_ext *e, 65 int error) 66 { 67 struct aa_profile *profile = labels_profile(aa_current_raw_label()); 68 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE, NULL); 69 if (e) 70 ad.iface.pos = e->pos - e->start; 71 ad.iface.ns = ns_name; 72 if (new) 73 ad.name = new->base.hname; 74 else 75 ad.name = name; 76 ad.info = info; 77 ad.error = error; 78 79 return aa_audit(AUDIT_APPARMOR_STATUS, profile, &ad, audit_cb); 80 } 81 82 void __aa_loaddata_update(struct aa_loaddata *data, long revision) 83 { 84 AA_BUG(!data); 85 AA_BUG(!data->ns); 86 AA_BUG(!mutex_is_locked(&data->ns->lock)); 87 AA_BUG(data->revision > revision); 88 89 data->revision = revision; 90 if ((data->dents[AAFS_LOADDATA_REVISION])) { 91 struct inode *inode; 92 93 inode = d_inode(data->dents[AAFS_LOADDATA_DIR]); 94 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); 95 96 inode = d_inode(data->dents[AAFS_LOADDATA_REVISION]); 97 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); 98 } 99 } 100 101 bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r) 102 { 103 if (l->size != r->size) 104 return false; 105 if (l->compressed_size != r->compressed_size) 106 return false; 107 if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0) 108 return false; 109 return memcmp(l->data, r->data, r->compressed_size ?: r->size) == 0; 110 } 111 112 /* 113 * need to take the ns mutex lock which is NOT safe most places that 114 * put_loaddata is called, so we have to delay freeing it 115 */ 116 static void do_loaddata_free(struct work_struct *work) 117 { 118 struct aa_loaddata *d = container_of(work, struct aa_loaddata, work); 119 struct aa_ns *ns = aa_get_ns(d->ns); 120 121 if (ns) { 122 mutex_lock_nested(&ns->lock, ns->level); 123 __aa_fs_remove_rawdata(d); 124 mutex_unlock(&ns->lock); 125 aa_put_ns(ns); 126 } 127 128 kfree_sensitive(d->hash); 129 kfree_sensitive(d->name); 130 kvfree(d->data); 131 kfree_sensitive(d); 132 } 133 134 void aa_loaddata_kref(struct kref *kref) 135 { 136 struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count); 137 138 if (d) { 139 INIT_WORK(&d->work, do_loaddata_free); 140 schedule_work(&d->work); 141 } 142 } 143 144 struct aa_loaddata *aa_loaddata_alloc(size_t size) 145 { 146 struct aa_loaddata *d; 147 148 d = kzalloc_obj(*d); 149 if (d == NULL) 150 return ERR_PTR(-ENOMEM); 151 d->data = kvzalloc(size, GFP_KERNEL); 152 if (!d->data) { 153 kfree(d); 154 return ERR_PTR(-ENOMEM); 155 } 156 kref_init(&d->count); 157 INIT_LIST_HEAD(&d->list); 158 159 return d; 160 } 161 162 /* test if read will be in packed data bounds */ 163 VISIBLE_IF_KUNIT bool aa_inbounds(struct aa_ext *e, size_t size) 164 { 165 return (size <= e->end - e->pos); 166 } 167 EXPORT_SYMBOL_IF_KUNIT(aa_inbounds); 168 169 /** 170 * aa_unpack_u16_chunk - test and do bounds checking for a u16 size based chunk 171 * @e: serialized data read head (NOT NULL) 172 * @chunk: start address for chunk of data (NOT NULL) 173 * 174 * Returns: the size of chunk found with the read head at the end of the chunk. 175 */ 176 VISIBLE_IF_KUNIT size_t aa_unpack_u16_chunk(struct aa_ext *e, char **chunk) 177 { 178 size_t size = 0; 179 void *pos = e->pos; 180 181 if (!aa_inbounds(e, sizeof(u16))) 182 goto fail; 183 size = le16_to_cpu(get_unaligned((__le16 *) e->pos)); 184 e->pos += sizeof(__le16); 185 if (!aa_inbounds(e, size)) 186 goto fail; 187 *chunk = e->pos; 188 e->pos += size; 189 return size; 190 191 fail: 192 e->pos = pos; 193 return 0; 194 } 195 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u16_chunk); 196 197 /* unpack control byte */ 198 VISIBLE_IF_KUNIT bool aa_unpack_X(struct aa_ext *e, enum aa_code code) 199 { 200 if (!aa_inbounds(e, 1)) 201 return false; 202 if (*(u8 *) e->pos != code) 203 return false; 204 e->pos++; 205 return true; 206 } 207 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_X); 208 209 /** 210 * aa_unpack_nameX - check is the next element is of type X with a name of @name 211 * @e: serialized data extent information (NOT NULL) 212 * @code: type code 213 * @name: name to match to the serialized element. (MAYBE NULL) 214 * 215 * check that the next serialized data element is of type X and has a tag 216 * name @name. If @name is specified then there must be a matching 217 * name element in the stream. If @name is NULL any name element will be 218 * skipped and only the typecode will be tested. 219 * 220 * Returns true on success (both type code and name tests match) and the read 221 * head is advanced past the headers 222 * 223 * Returns: false if either match fails, the read head does not move 224 */ 225 VISIBLE_IF_KUNIT bool aa_unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name) 226 { 227 /* 228 * May need to reset pos if name or type doesn't match 229 */ 230 void *pos = e->pos; 231 /* 232 * Check for presence of a tagname, and if present name size 233 * AA_NAME tag value is a u16. 234 */ 235 if (aa_unpack_X(e, AA_NAME)) { 236 char *tag = NULL; 237 size_t size = aa_unpack_u16_chunk(e, &tag); 238 /* if a name is specified it must match. otherwise skip tag */ 239 if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag))) 240 goto fail; 241 } else if (name) { 242 /* if a name is specified and there is no name tag fail */ 243 goto fail; 244 } 245 246 /* now check if type code matches */ 247 if (aa_unpack_X(e, code)) 248 return true; 249 250 fail: 251 e->pos = pos; 252 return false; 253 } 254 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_nameX); 255 256 static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name) 257 { 258 void *pos = e->pos; 259 260 if (aa_unpack_nameX(e, AA_U8, name)) { 261 if (!aa_inbounds(e, sizeof(u8))) 262 goto fail; 263 if (data) 264 *data = *((u8 *)e->pos); 265 e->pos += sizeof(u8); 266 return true; 267 } 268 269 fail: 270 e->pos = pos; 271 return false; 272 } 273 274 VISIBLE_IF_KUNIT bool aa_unpack_u32(struct aa_ext *e, u32 *data, const char *name) 275 { 276 void *pos = e->pos; 277 278 if (aa_unpack_nameX(e, AA_U32, name)) { 279 if (!aa_inbounds(e, sizeof(u32))) 280 goto fail; 281 if (data) 282 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos)); 283 e->pos += sizeof(u32); 284 return true; 285 } 286 287 fail: 288 e->pos = pos; 289 return false; 290 } 291 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u32); 292 293 VISIBLE_IF_KUNIT bool aa_unpack_u64(struct aa_ext *e, u64 *data, const char *name) 294 { 295 void *pos = e->pos; 296 297 if (aa_unpack_nameX(e, AA_U64, name)) { 298 if (!aa_inbounds(e, sizeof(u64))) 299 goto fail; 300 if (data) 301 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos)); 302 e->pos += sizeof(u64); 303 return true; 304 } 305 306 fail: 307 e->pos = pos; 308 return false; 309 } 310 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u64); 311 312 static bool aa_unpack_cap_low(struct aa_ext *e, kernel_cap_t *data, const char *name) 313 { 314 u32 val; 315 316 if (!aa_unpack_u32(e, &val, name)) 317 return false; 318 data->val = val; 319 return true; 320 } 321 322 static bool aa_unpack_cap_high(struct aa_ext *e, kernel_cap_t *data, const char *name) 323 { 324 u32 val; 325 326 if (!aa_unpack_u32(e, &val, name)) 327 return false; 328 data->val = (u32)data->val | ((u64)val << 32); 329 return true; 330 } 331 332 VISIBLE_IF_KUNIT bool aa_unpack_array(struct aa_ext *e, const char *name, u16 *size) 333 { 334 void *pos = e->pos; 335 336 if (aa_unpack_nameX(e, AA_ARRAY, name)) { 337 if (!aa_inbounds(e, sizeof(u16))) 338 goto fail; 339 *size = le16_to_cpu(get_unaligned((__le16 *) e->pos)); 340 e->pos += sizeof(u16); 341 return true; 342 } 343 344 fail: 345 e->pos = pos; 346 return false; 347 } 348 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_array); 349 350 VISIBLE_IF_KUNIT size_t aa_unpack_blob(struct aa_ext *e, char **blob, const char *name) 351 { 352 void *pos = e->pos; 353 354 if (aa_unpack_nameX(e, AA_BLOB, name)) { 355 u32 size; 356 if (!aa_inbounds(e, sizeof(u32))) 357 goto fail; 358 size = le32_to_cpu(get_unaligned((__le32 *) e->pos)); 359 e->pos += sizeof(u32); 360 if (aa_inbounds(e, (size_t) size)) { 361 *blob = e->pos; 362 e->pos += size; 363 return size; 364 } 365 } 366 367 fail: 368 e->pos = pos; 369 return 0; 370 } 371 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_blob); 372 373 VISIBLE_IF_KUNIT int aa_unpack_str(struct aa_ext *e, const char **string, const char *name) 374 { 375 char *src_str; 376 size_t size = 0; 377 void *pos = e->pos; 378 *string = NULL; 379 if (aa_unpack_nameX(e, AA_STRING, name)) { 380 size = aa_unpack_u16_chunk(e, &src_str); 381 if (size) { 382 /* strings are null terminated, length is size - 1 */ 383 if (src_str[size - 1] != 0) 384 goto fail; 385 *string = src_str; 386 387 return size; 388 } 389 } 390 391 fail: 392 e->pos = pos; 393 return 0; 394 } 395 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_str); 396 397 VISIBLE_IF_KUNIT int aa_unpack_strdup(struct aa_ext *e, char **string, const char *name) 398 { 399 const char *tmp; 400 void *pos = e->pos; 401 int res = aa_unpack_str(e, &tmp, name); 402 *string = NULL; 403 404 if (!res) 405 return 0; 406 407 *string = kmemdup(tmp, res, GFP_KERNEL); 408 if (!*string) { 409 e->pos = pos; 410 return 0; 411 } 412 413 return res; 414 } 415 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_strdup); 416 417 418 /** 419 * unpack_dfa - unpack a file rule dfa 420 * @e: serialized data extent information (NOT NULL) 421 * @flags: dfa flags to check 422 * 423 * returns dfa or ERR_PTR or NULL if no dfa 424 */ 425 static struct aa_dfa *unpack_dfa(struct aa_ext *e, int flags) 426 { 427 char *blob = NULL; 428 size_t size; 429 struct aa_dfa *dfa = NULL; 430 431 size = aa_unpack_blob(e, &blob, "aadfa"); 432 if (size) { 433 /* 434 * The dfa is aligned with in the blob to 8 bytes 435 * from the beginning of the stream. 436 * alignment adjust needed by dfa unpack 437 */ 438 size_t sz = blob - (char *) e->start - 439 ((e->pos - e->start) & 7); 440 size_t pad = ALIGN(sz, 8) - sz; 441 if (aa_g_paranoid_load) 442 flags |= DFA_FLAG_VERIFY_STATES; 443 dfa = aa_dfa_unpack(blob + pad, size - pad, flags); 444 445 if (IS_ERR(dfa)) 446 return dfa; 447 448 } 449 450 return dfa; 451 } 452 453 static int process_strs_entry(char *str, int size, bool multi) 454 { 455 int c = 1; 456 457 if (size <= 0) 458 return -1; 459 if (multi) { 460 if (size < 2) 461 return -2; 462 /* multi ends with double \0 */ 463 if (str[size - 2]) 464 return -3; 465 } 466 467 char *save = str; 468 char *pos = str; 469 char *end = multi ? str + size - 2 : str + size - 1; 470 /* count # of internal \0 */ 471 while (str < end) { 472 if (str == pos) { 473 /* starts with ... */ 474 if (!*str) { 475 AA_DEBUG(DEBUG_UNPACK, 476 "starting with null save=%lu size %d c=%d", 477 (unsigned long)(str - save), size, c); 478 return -4; 479 } 480 if (isspace(*str)) 481 return -5; 482 if (*str == ':') { 483 /* :ns_str\0str\0 484 * first character after : must be valid 485 */ 486 if (!str[1]) 487 return -6; 488 } 489 } else if (!*str) { 490 if (*pos == ':') 491 *str = ':'; 492 else 493 c++; 494 pos = str + 1; 495 } 496 str++; 497 } /* while */ 498 499 return c; 500 } 501 502 /** 503 * unpack_strs_table - unpack a profile transition table 504 * @e: serialized data extent information (NOT NULL) 505 * @name: name of table (MAY BE NULL) 506 * @multi: allow multiple strings on a single entry 507 * @strs: str table to unpack to (NOT NULL) 508 * 509 * Returns: 0 if table successfully unpacked or not present, else error 510 */ 511 static int unpack_strs_table(struct aa_ext *e, const char *name, bool multi, 512 struct aa_str_table *strs) 513 { 514 void *saved_pos = e->pos; 515 struct aa_str_table_ent *table = NULL; 516 int error = -EPROTO; 517 518 /* exec table is optional */ 519 if (aa_unpack_nameX(e, AA_STRUCT, name)) { 520 u16 size; 521 int i; 522 523 if (!aa_unpack_array(e, NULL, &size)) 524 /* 525 * Note: index into trans table array is a max 526 * of 2^24, but unpack array can only unpack 527 * an array of 2^16 in size atm so no need 528 * for size check here 529 */ 530 goto fail; 531 table = kzalloc_objs(struct aa_str_table_ent, size); 532 if (!table) { 533 error = -ENOMEM; 534 goto fail; 535 } 536 strs->table = table; 537 strs->size = size; 538 for (i = 0; i < size; i++) { 539 char *str; 540 int c, size2 = aa_unpack_strdup(e, &str, NULL); 541 /* aa_unpack_strdup verifies that the last character is 542 * null termination byte. 543 */ 544 c = process_strs_entry(str, size2, multi); 545 if (c <= 0) { 546 AA_DEBUG(DEBUG_UNPACK, "process_strs %d i %d pos %ld", 547 c, i, 548 (unsigned long)(e->pos - saved_pos)); 549 goto fail; 550 } 551 if (!multi && c > 1) { 552 AA_DEBUG(DEBUG_UNPACK, "!multi && c > 1"); 553 /* fail - all other cases with embedded \0 */ 554 goto fail; 555 } 556 table[i].strs = str; 557 table[i].count = c; 558 table[i].size = size2; 559 } 560 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 561 goto fail; 562 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 563 goto fail; 564 } 565 return 0; 566 567 fail: 568 aa_destroy_str_table(strs); 569 e->pos = saved_pos; 570 return error; 571 } 572 573 static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile) 574 { 575 void *pos = e->pos; 576 577 if (aa_unpack_nameX(e, AA_STRUCT, "xattrs")) { 578 u16 size; 579 int i; 580 581 if (!aa_unpack_array(e, NULL, &size)) 582 goto fail; 583 profile->attach.xattr_count = size; 584 profile->attach.xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL); 585 if (!profile->attach.xattrs) 586 goto fail; 587 for (i = 0; i < size; i++) { 588 if (!aa_unpack_strdup(e, &profile->attach.xattrs[i], NULL)) 589 goto fail; 590 } 591 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 592 goto fail; 593 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 594 goto fail; 595 } 596 597 return true; 598 599 fail: 600 e->pos = pos; 601 return false; 602 } 603 604 static bool unpack_secmark(struct aa_ext *e, struct aa_ruleset *rules) 605 { 606 void *pos = e->pos; 607 u16 size; 608 int i; 609 610 if (aa_unpack_nameX(e, AA_STRUCT, "secmark")) { 611 if (!aa_unpack_array(e, NULL, &size)) 612 goto fail; 613 614 rules->secmark = kzalloc_objs(struct aa_secmark, size); 615 if (!rules->secmark) 616 goto fail; 617 618 rules->secmark_count = size; 619 620 for (i = 0; i < size; i++) { 621 if (!unpack_u8(e, &rules->secmark[i].audit, NULL)) 622 goto fail; 623 if (!unpack_u8(e, &rules->secmark[i].deny, NULL)) 624 goto fail; 625 if (!aa_unpack_strdup(e, &rules->secmark[i].label, NULL)) 626 goto fail; 627 } 628 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 629 goto fail; 630 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 631 goto fail; 632 } 633 634 return true; 635 636 fail: 637 if (rules->secmark) { 638 for (i = 0; i < size; i++) 639 kfree_sensitive(rules->secmark[i].label); 640 kfree_sensitive(rules->secmark); 641 rules->secmark_count = 0; 642 rules->secmark = NULL; 643 } 644 645 e->pos = pos; 646 return false; 647 } 648 649 static bool unpack_rlimits(struct aa_ext *e, struct aa_ruleset *rules) 650 { 651 void *pos = e->pos; 652 653 /* rlimits are optional */ 654 if (aa_unpack_nameX(e, AA_STRUCT, "rlimits")) { 655 u16 size; 656 int i; 657 u32 tmp = 0; 658 if (!aa_unpack_u32(e, &tmp, NULL)) 659 goto fail; 660 rules->rlimits.mask = tmp; 661 662 if (!aa_unpack_array(e, NULL, &size) || 663 size > RLIM_NLIMITS) 664 goto fail; 665 for (i = 0; i < size; i++) { 666 u64 tmp2 = 0; 667 int a = aa_map_resource(i); 668 if (!aa_unpack_u64(e, &tmp2, NULL)) 669 goto fail; 670 rules->rlimits.limits[a].rlim_max = tmp2; 671 } 672 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 673 goto fail; 674 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 675 goto fail; 676 } 677 return true; 678 679 fail: 680 e->pos = pos; 681 return false; 682 } 683 684 685 static bool verify_tags(struct aa_tags_struct *tags, const char **info) 686 { 687 if ((tags->hdrs.size && !tags->hdrs.table) || 688 (!tags->hdrs.size && tags->hdrs.table)) { 689 *info = "failed verification tag.hdrs disagree"; 690 return false; 691 } 692 if ((tags->sets.size && !tags->sets.table) || 693 (!tags->sets.size && tags->sets.table)) { 694 *info = "failed verification tag.sets disagree"; 695 return false; 696 } 697 if ((tags->strs.size && !tags->strs.table) || 698 (!tags->strs.size && tags->strs.table)) { 699 *info = "failed verification tags->strs disagree"; 700 return false; 701 } 702 /* no data present */ 703 if (!tags->sets.size && !tags->hdrs.size && !tags->strs.size) { 704 return true; 705 } else if (!(tags->sets.size && tags->hdrs.size && tags->strs.size)) { 706 /* some data present but not all */ 707 *info = "failed verification tags partial data present"; 708 return false; 709 } 710 711 u32 i; 712 713 for (i = 0; i < tags->sets.size; i++) { 714 /* count followed by count indexes into hdrs */ 715 u32 cnt = tags->sets.table[i]; 716 717 if (i+cnt >= tags->sets.size) { 718 AA_DEBUG(DEBUG_UNPACK, 719 "tagset too large %d+%d > sets.table[%d]", 720 i, cnt, tags->sets.size); 721 *info = "failed verification tagset too large"; 722 return false; 723 } 724 for (; cnt; cnt--) { 725 if (tags->sets.table[++i] >= tags->hdrs.size) { 726 AA_DEBUG(DEBUG_UNPACK, 727 "tagsets idx out of bounds cnt %d sets.table[%d] >= %d", 728 cnt, i-1, tags->hdrs.size); 729 *info = "failed verification tagsets idx out of bounds"; 730 return false; 731 } 732 } 733 } 734 for (i = 0; i < tags->hdrs.size; i++) { 735 u32 idx = tags->hdrs.table[i].tags; 736 737 if (idx >= tags->strs.size) { 738 AA_DEBUG(DEBUG_UNPACK, 739 "tag.hdrs idx oob idx %d > tags->strs.size=%d", 740 idx, tags->strs.size); 741 *info = "failed verification tags.hdrs idx out of bounds"; 742 return false; 743 } 744 if (tags->hdrs.table[i].count != tags->strs.table[idx].count) { 745 AA_DEBUG(DEBUG_UNPACK, "hdrs.table[%d].count=%d != tags->strs.table[%d]=%d", 746 i, tags->hdrs.table[i].count, idx, tags->strs.table[idx].count); 747 *info = "failed verification tagd.hdrs[idx].count"; 748 return false; 749 } 750 if (tags->hdrs.table[i].size != tags->strs.table[idx].size) { 751 AA_DEBUG(DEBUG_UNPACK, "hdrs.table[%d].size=%d != strs.table[%d].size=%d", 752 i, tags->hdrs.table[i].size, idx, tags->strs.table[idx].size); 753 *info = "failed verification tagd.hdrs[idx].size"; 754 return false; 755 } 756 } 757 758 return true; 759 } 760 761 static int unpack_tagsets(struct aa_ext *e, struct aa_tags_struct *tags) 762 { 763 u32 *sets; 764 u16 i, size; 765 int error = -EPROTO; 766 void *pos = e->pos; 767 768 if (!aa_unpack_array(e, "sets", &size)) 769 goto fail_reset; 770 sets = kcalloc(size, sizeof(u32), GFP_KERNEL); 771 if (!sets) { 772 error = -ENOMEM; 773 goto fail_reset; 774 } 775 for (i = 0; i < size; i++) { 776 if (!aa_unpack_u32(e, &sets[i], NULL)) 777 goto fail; 778 } 779 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 780 goto fail; 781 782 tags->sets.size = size; 783 tags->sets.table = sets; 784 785 return 0; 786 787 fail: 788 kfree_sensitive(sets); 789 fail_reset: 790 e->pos = pos; 791 return error; 792 } 793 794 static bool unpack_tag_header_ent(struct aa_ext *e, struct aa_tags_header *h) 795 { 796 return aa_unpack_u32(e, &h->mask, NULL) && 797 aa_unpack_u32(e, &h->count, NULL) && 798 aa_unpack_u32(e, &h->size, NULL) && 799 aa_unpack_u32(e, &h->tags, NULL); 800 } 801 802 static int unpack_tag_headers(struct aa_ext *e, struct aa_tags_struct *tags) 803 { 804 struct aa_tags_header *hdrs; 805 u16 i, size; 806 int error = -EPROTO; 807 void *pos = e->pos; 808 809 if (!aa_unpack_array(e, "hdrs", &size)) 810 goto fail_reset; 811 hdrs = kzalloc_objs(struct aa_tags_header, size); 812 if (!hdrs) { 813 error = -ENOMEM; 814 goto fail_reset; 815 } 816 for (i = 0; i < size; i++) { 817 if (!unpack_tag_header_ent(e, &hdrs[i])) 818 goto fail; 819 } 820 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 821 goto fail; 822 823 tags->hdrs.size = size; 824 tags->hdrs.table = hdrs; 825 AA_DEBUG(DEBUG_UNPACK, "headers %ld size %d", (long) hdrs, size); 826 return true; 827 828 fail: 829 kfree_sensitive(hdrs); 830 fail_reset: 831 e->pos = pos; 832 return error; 833 } 834 835 836 static int unpack_tags(struct aa_ext *e, struct aa_tags_struct *tags, 837 const char **info) 838 { 839 int error = -EPROTO; 840 void *pos = e->pos; 841 842 AA_BUG(!tags); 843 /* policy tags are optional */ 844 if (aa_unpack_nameX(e, AA_STRUCT, "tags")) { 845 u32 version; 846 847 if (!aa_unpack_u32(e, &version, "version") || version != 1) { 848 *info = "invalid tags version"; 849 goto fail_reset; 850 } 851 error = unpack_strs_table(e, "strs", true, &tags->strs); 852 if (error) { 853 *info = "failed to unpack profile tag.strs"; 854 goto fail; 855 } 856 error = unpack_tag_headers(e, tags); 857 if (error) { 858 *info = "failed to unpack profile tag.headers"; 859 goto fail; 860 } 861 error = unpack_tagsets(e, tags); 862 if (error) { 863 *info = "failed to unpack profile tag.sets"; 864 goto fail; 865 } 866 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 867 goto fail; 868 869 if (!verify_tags(tags, info)) 870 goto fail; 871 } 872 873 return 0; 874 875 fail: 876 aa_destroy_tags(tags); 877 fail_reset: 878 e->pos = pos; 879 return error; 880 } 881 882 static bool unpack_perm(struct aa_ext *e, u32 version, struct aa_perms *perm) 883 { 884 u32 reserved; 885 886 if (version != 1) 887 return false; 888 889 /* reserved entry is for later expansion, discard for now */ 890 return aa_unpack_u32(e, &reserved, NULL) && 891 aa_unpack_u32(e, &perm->allow, NULL) && 892 aa_unpack_u32(e, &perm->deny, NULL) && 893 aa_unpack_u32(e, &perm->subtree, NULL) && 894 aa_unpack_u32(e, &perm->cond, NULL) && 895 aa_unpack_u32(e, &perm->kill, NULL) && 896 aa_unpack_u32(e, &perm->complain, NULL) && 897 aa_unpack_u32(e, &perm->prompt, NULL) && 898 aa_unpack_u32(e, &perm->audit, NULL) && 899 aa_unpack_u32(e, &perm->quiet, NULL) && 900 aa_unpack_u32(e, &perm->hide, NULL) && 901 aa_unpack_u32(e, &perm->xindex, NULL) && 902 aa_unpack_u32(e, &perm->tag, NULL) && 903 aa_unpack_u32(e, &perm->label, NULL); 904 } 905 906 static ssize_t unpack_perms_table(struct aa_ext *e, struct aa_perms **perms) 907 { 908 void *pos = e->pos; 909 u16 size = 0; 910 911 AA_BUG(!perms); 912 /* 913 * policy perms are optional, in which case perms are embedded 914 * in the dfa accept table 915 */ 916 if (aa_unpack_nameX(e, AA_STRUCT, "perms")) { 917 int i; 918 u32 version; 919 920 if (!aa_unpack_u32(e, &version, "version")) 921 goto fail_reset; 922 if (!aa_unpack_array(e, NULL, &size)) 923 goto fail_reset; 924 *perms = kzalloc_objs(struct aa_perms, size); 925 if (!*perms) { 926 e->pos = pos; 927 return -ENOMEM; 928 } 929 for (i = 0; i < size; i++) { 930 if (!unpack_perm(e, version, &(*perms)[i])) 931 goto fail; 932 } 933 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 934 goto fail; 935 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 936 goto fail; 937 } else 938 *perms = NULL; 939 940 return size; 941 942 fail: 943 kfree(*perms); 944 fail_reset: 945 e->pos = pos; 946 return -EPROTO; 947 } 948 949 static int unpack_pdb(struct aa_ext *e, struct aa_policydb **policy, 950 bool required_dfa, bool required_trans, 951 const char **info) 952 { 953 struct aa_policydb *pdb; 954 void *pos = e->pos; 955 int i, flags, error = -EPROTO; 956 ssize_t size; 957 u32 version = 0; 958 959 pdb = aa_alloc_pdb(GFP_KERNEL); 960 if (!pdb) 961 return -ENOMEM; 962 963 AA_DEBUG(DEBUG_UNPACK, "unpacking tags"); 964 if (unpack_tags(e, &pdb->tags, info) < 0) 965 goto fail; 966 AA_DEBUG(DEBUG_UNPACK, "done unpacking tags"); 967 968 size = unpack_perms_table(e, &pdb->perms); 969 if (size < 0) { 970 error = size; 971 pdb->perms = NULL; 972 *info = "failed to unpack - perms"; 973 goto fail; 974 } 975 pdb->size = size; 976 977 if (pdb->perms) { 978 /* perms table present accept is index */ 979 flags = TO_ACCEPT1_FLAG(YYTD_DATA32); 980 if (aa_unpack_u32(e, &version, "permsv") && version > 2) 981 /* accept2 used for dfa flags */ 982 flags |= TO_ACCEPT2_FLAG(YYTD_DATA32); 983 } else { 984 /* packed perms in accept1 and accept2 */ 985 flags = TO_ACCEPT1_FLAG(YYTD_DATA32) | 986 TO_ACCEPT2_FLAG(YYTD_DATA32); 987 } 988 989 pdb->dfa = unpack_dfa(e, flags); 990 if (IS_ERR(pdb->dfa)) { 991 error = PTR_ERR(pdb->dfa); 992 pdb->dfa = NULL; 993 *info = "failed to unpack - dfa"; 994 goto fail; 995 } else if (!pdb->dfa) { 996 if (required_dfa) { 997 *info = "missing required dfa"; 998 goto fail; 999 } 1000 } else { 1001 /* 1002 * only unpack the following if a dfa is present 1003 * 1004 * sadly start was given different names for file and policydb 1005 * but since it is optional we can try both 1006 */ 1007 if (!aa_unpack_u32(e, &pdb->start[0], "start")) 1008 /* default start state */ 1009 pdb->start[0] = DFA_START; 1010 if (!aa_unpack_u32(e, &pdb->start[AA_CLASS_FILE], "dfa_start")) { 1011 /* default start state for xmatch and file dfa */ 1012 pdb->start[AA_CLASS_FILE] = DFA_START; 1013 } /* setup class index */ 1014 for (i = AA_CLASS_FILE + 1; i <= AA_CLASS_LAST; i++) { 1015 pdb->start[i] = aa_dfa_next(pdb->dfa, pdb->start[0], 1016 i); 1017 } 1018 } 1019 1020 /* accept2 is in some cases being allocated, even with perms */ 1021 if (pdb->perms && !pdb->dfa->tables[YYTD_ID_ACCEPT2]) { 1022 /* add dfa flags table missing in v2 */ 1023 u32 noents = pdb->dfa->tables[YYTD_ID_ACCEPT]->td_lolen; 1024 u16 tdflags = pdb->dfa->tables[YYTD_ID_ACCEPT]->td_flags; 1025 size_t tsize = table_size(noents, tdflags); 1026 1027 pdb->dfa->tables[YYTD_ID_ACCEPT2] = kvzalloc(tsize, GFP_KERNEL); 1028 if (!pdb->dfa->tables[YYTD_ID_ACCEPT2]) { 1029 *info = "failed to alloc dfa flags table"; 1030 goto out; 1031 } 1032 pdb->dfa->tables[YYTD_ID_ACCEPT2]->td_lolen = noents; 1033 pdb->dfa->tables[YYTD_ID_ACCEPT2]->td_flags = tdflags; 1034 } 1035 /* 1036 * Unfortunately due to a bug in earlier userspaces, a 1037 * transition table may be present even when the dfa is 1038 * not. For compatibility reasons unpack and discard. 1039 */ 1040 error = unpack_strs_table(e, "xtable", false, &pdb->trans); 1041 if (error && required_trans) { 1042 *info = "failed to unpack profile transition table"; 1043 goto fail; 1044 } 1045 1046 if (!pdb->dfa && pdb->trans.table) 1047 aa_destroy_str_table(&pdb->trans); 1048 1049 /* TODO: 1050 * - move compat mapping here, requires dfa merging first 1051 * - move verify here, it has to be done after compat mappings 1052 * - move free of unneeded trans table here, has to be done 1053 * after perm mapping. 1054 */ 1055 out: 1056 *policy = pdb; 1057 return 0; 1058 1059 fail: 1060 aa_put_pdb(pdb); 1061 e->pos = pos; 1062 return error; 1063 } 1064 1065 static u32 strhash(const void *data, u32 len, u32 seed) 1066 { 1067 const char * const *key = data; 1068 1069 return jhash(*key, strlen(*key), seed); 1070 } 1071 1072 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj) 1073 { 1074 const struct aa_data *data = obj; 1075 const char * const *key = arg->key; 1076 1077 return strcmp(data->key, *key); 1078 } 1079 1080 /** 1081 * unpack_profile - unpack a serialized profile 1082 * @e: serialized data extent information (NOT NULL) 1083 * @ns_name: pointer of newly allocated copy of %NULL in case of error 1084 * 1085 * NOTE: unpack profile sets audit struct if there is a failure 1086 */ 1087 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name) 1088 { 1089 struct aa_ruleset *rules; 1090 struct aa_profile *profile = NULL; 1091 const char *tmpname, *tmpns = NULL, *name = NULL; 1092 const char *info = "failed to unpack profile"; 1093 size_t ns_len; 1094 struct rhashtable_params params = { 0 }; 1095 char *key = NULL, *disconnected = NULL; 1096 struct aa_data *data; 1097 int error = -EPROTO; 1098 kernel_cap_t tmpcap; 1099 u32 tmp; 1100 1101 *ns_name = NULL; 1102 1103 /* check that we have the right struct being passed */ 1104 if (!aa_unpack_nameX(e, AA_STRUCT, "profile")) 1105 goto fail; 1106 if (!aa_unpack_str(e, &name, NULL)) 1107 goto fail; 1108 if (*name == '\0') 1109 goto fail; 1110 1111 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len); 1112 if (tmpns) { 1113 if (!tmpname) { 1114 info = "empty profile name"; 1115 goto fail; 1116 } 1117 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL); 1118 if (!*ns_name) { 1119 info = "out of memory"; 1120 error = -ENOMEM; 1121 goto fail; 1122 } 1123 name = tmpname; 1124 } 1125 1126 profile = aa_alloc_profile(name, NULL, GFP_KERNEL); 1127 if (!profile) { 1128 info = "out of memory"; 1129 error = -ENOMEM; 1130 goto fail; 1131 } 1132 rules = profile->label.rules[0]; 1133 1134 /* profile renaming is optional */ 1135 (void) aa_unpack_str(e, &profile->rename, "rename"); 1136 1137 /* attachment string is optional */ 1138 (void) aa_unpack_str(e, &profile->attach.xmatch_str, "attach"); 1139 1140 /* xmatch is optional and may be NULL */ 1141 error = unpack_pdb(e, &profile->attach.xmatch, false, false, &info); 1142 if (error) { 1143 info = "bad xmatch"; 1144 goto fail; 1145 } 1146 1147 /* neither xmatch_len not xmatch_perms are optional if xmatch is set */ 1148 if (profile->attach.xmatch->dfa) { 1149 if (!aa_unpack_u32(e, &tmp, NULL)) { 1150 info = "missing xmatch len"; 1151 goto fail; 1152 } 1153 profile->attach.xmatch_len = tmp; 1154 profile->attach.xmatch->start[AA_CLASS_XMATCH] = DFA_START; 1155 if (!profile->attach.xmatch->perms) { 1156 error = aa_compat_map_xmatch(profile->attach.xmatch); 1157 if (error) { 1158 info = "failed to convert xmatch permission table"; 1159 goto fail; 1160 } 1161 } 1162 } 1163 1164 /* disconnected attachment string is optional */ 1165 (void) aa_unpack_strdup(e, &disconnected, "disconnected"); 1166 profile->disconnected = disconnected; 1167 1168 /* optional */ 1169 (void) aa_unpack_u32(e, &profile->signal, "kill"); 1170 if (profile->signal < 1 || profile->signal > MAXMAPPED_SIG) { 1171 info = "profile kill.signal invalid value"; 1172 goto fail; 1173 } 1174 /* per profile debug flags (complain, audit) */ 1175 if (!aa_unpack_nameX(e, AA_STRUCT, "flags")) { 1176 info = "profile missing flags"; 1177 goto fail; 1178 } 1179 info = "failed to unpack profile flags"; 1180 if (!aa_unpack_u32(e, &tmp, NULL)) 1181 goto fail; 1182 if (tmp & PACKED_FLAG_HAT) 1183 profile->label.flags |= FLAG_HAT; 1184 if (tmp & PACKED_FLAG_DEBUG1) 1185 profile->label.flags |= FLAG_DEBUG1; 1186 if (tmp & PACKED_FLAG_DEBUG2) 1187 profile->label.flags |= FLAG_DEBUG2; 1188 if (!aa_unpack_u32(e, &tmp, NULL)) 1189 goto fail; 1190 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG)) { 1191 profile->mode = APPARMOR_COMPLAIN; 1192 } else if (tmp == PACKED_MODE_ENFORCE) { 1193 profile->mode = APPARMOR_ENFORCE; 1194 } else if (tmp == PACKED_MODE_KILL) { 1195 profile->mode = APPARMOR_KILL; 1196 } else if (tmp == PACKED_MODE_UNCONFINED) { 1197 profile->mode = APPARMOR_UNCONFINED; 1198 profile->label.flags |= FLAG_UNCONFINED; 1199 } else if (tmp == PACKED_MODE_USER) { 1200 profile->mode = APPARMOR_USER; 1201 } else { 1202 goto fail; 1203 } 1204 if (!aa_unpack_u32(e, &tmp, NULL)) 1205 goto fail; 1206 if (tmp) 1207 profile->audit = AUDIT_ALL; 1208 1209 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 1210 goto fail; 1211 1212 /* path_flags is optional */ 1213 if (aa_unpack_u32(e, &profile->path_flags, "path_flags")) 1214 profile->path_flags |= profile->label.flags & 1215 PATH_MEDIATE_DELETED; 1216 else 1217 /* set a default value if path_flags field is not present */ 1218 profile->path_flags = PATH_MEDIATE_DELETED; 1219 1220 info = "failed to unpack profile capabilities"; 1221 if (!aa_unpack_cap_low(e, &rules->caps.allow, NULL)) 1222 goto fail; 1223 if (!aa_unpack_cap_low(e, &rules->caps.audit, NULL)) 1224 goto fail; 1225 if (!aa_unpack_cap_low(e, &rules->caps.quiet, NULL)) 1226 goto fail; 1227 if (!aa_unpack_cap_low(e, &tmpcap, NULL)) 1228 goto fail; 1229 1230 info = "failed to unpack upper profile capabilities"; 1231 if (aa_unpack_nameX(e, AA_STRUCT, "caps64")) { 1232 /* optional upper half of 64 bit caps */ 1233 if (!aa_unpack_cap_high(e, &rules->caps.allow, NULL)) 1234 goto fail; 1235 if (!aa_unpack_cap_high(e, &rules->caps.audit, NULL)) 1236 goto fail; 1237 if (!aa_unpack_cap_high(e, &rules->caps.quiet, NULL)) 1238 goto fail; 1239 if (!aa_unpack_cap_high(e, &tmpcap, NULL)) 1240 goto fail; 1241 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 1242 goto fail; 1243 } 1244 1245 info = "failed to unpack extended profile capabilities"; 1246 if (aa_unpack_nameX(e, AA_STRUCT, "capsx")) { 1247 /* optional extended caps mediation mask */ 1248 if (!aa_unpack_cap_low(e, &rules->caps.extended, NULL)) 1249 goto fail; 1250 if (!aa_unpack_cap_high(e, &rules->caps.extended, NULL)) 1251 goto fail; 1252 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 1253 goto fail; 1254 } 1255 1256 if (!unpack_xattrs(e, profile)) { 1257 info = "failed to unpack profile xattrs"; 1258 goto fail; 1259 } 1260 1261 if (!unpack_rlimits(e, rules)) { 1262 info = "failed to unpack profile rlimits"; 1263 goto fail; 1264 } 1265 1266 if (!unpack_secmark(e, rules)) { 1267 info = "failed to unpack profile secmark rules"; 1268 goto fail; 1269 } 1270 1271 if (aa_unpack_nameX(e, AA_STRUCT, "policydb")) { 1272 /* generic policy dfa - optional and may be NULL */ 1273 info = "failed to unpack policydb"; 1274 error = unpack_pdb(e, &rules->policy, true, false, 1275 &info); 1276 if (error) 1277 goto fail; 1278 /* Fixup: drop when we get rid of start array */ 1279 if (aa_dfa_next(rules->policy->dfa, rules->policy->start[0], 1280 AA_CLASS_FILE)) 1281 rules->policy->start[AA_CLASS_FILE] = 1282 aa_dfa_next(rules->policy->dfa, 1283 rules->policy->start[0], 1284 AA_CLASS_FILE); 1285 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 1286 goto fail; 1287 if (!rules->policy->perms) { 1288 error = aa_compat_map_policy(rules->policy, 1289 e->version); 1290 if (error) { 1291 info = "failed to remap policydb permission table"; 1292 goto fail; 1293 } 1294 } 1295 } else { 1296 rules->policy = aa_get_pdb(nullpdb); 1297 } 1298 /* get file rules */ 1299 error = unpack_pdb(e, &rules->file, false, true, &info); 1300 if (error) { 1301 goto fail; 1302 } else if (rules->file->dfa) { 1303 if (!rules->file->perms) { 1304 AA_DEBUG(DEBUG_UNPACK, "compat mapping perms"); 1305 error = aa_compat_map_file(rules->file); 1306 if (error) { 1307 info = "failed to remap file permission table"; 1308 goto fail; 1309 } 1310 } 1311 } else if (rules->policy->dfa && 1312 rules->policy->start[AA_CLASS_FILE]) { 1313 aa_put_pdb(rules->file); 1314 rules->file = aa_get_pdb(rules->policy); 1315 } else { 1316 aa_put_pdb(rules->file); 1317 rules->file = aa_get_pdb(nullpdb); 1318 } 1319 error = -EPROTO; 1320 if (aa_unpack_nameX(e, AA_STRUCT, "data")) { 1321 info = "out of memory"; 1322 profile->data = kzalloc_obj(*profile->data); 1323 if (!profile->data) { 1324 error = -ENOMEM; 1325 goto fail; 1326 } 1327 params.nelem_hint = 3; 1328 params.key_len = sizeof(void *); 1329 params.key_offset = offsetof(struct aa_data, key); 1330 params.head_offset = offsetof(struct aa_data, head); 1331 params.hashfn = strhash; 1332 params.obj_cmpfn = datacmp; 1333 1334 if (rhashtable_init(profile->data, ¶ms)) { 1335 info = "failed to init key, value hash table"; 1336 goto fail; 1337 } 1338 1339 while (aa_unpack_strdup(e, &key, NULL)) { 1340 data = kzalloc_obj(*data); 1341 if (!data) { 1342 kfree_sensitive(key); 1343 error = -ENOMEM; 1344 goto fail; 1345 } 1346 1347 data->key = key; 1348 data->size = aa_unpack_blob(e, &data->data, NULL); 1349 data->data = kvmemdup(data->data, data->size, GFP_KERNEL); 1350 if (data->size && !data->data) { 1351 kfree_sensitive(data->key); 1352 kfree_sensitive(data); 1353 error = -ENOMEM; 1354 goto fail; 1355 } 1356 1357 if (rhashtable_insert_fast(profile->data, &data->head, 1358 profile->data->p)) { 1359 kvfree_sensitive(data->data, data->size); 1360 kfree_sensitive(data->key); 1361 kfree_sensitive(data); 1362 info = "failed to insert data to table"; 1363 goto fail; 1364 } 1365 } 1366 1367 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) { 1368 info = "failed to unpack end of key, value data table"; 1369 goto fail; 1370 } 1371 } 1372 1373 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) { 1374 info = "failed to unpack end of profile"; 1375 goto fail; 1376 } 1377 1378 aa_compute_profile_mediates(profile); 1379 1380 return profile; 1381 1382 fail: 1383 if (error == 0) 1384 /* default error covers most cases */ 1385 error = -EPROTO; 1386 if (*ns_name) { 1387 kfree(*ns_name); 1388 *ns_name = NULL; 1389 } 1390 if (profile) 1391 name = NULL; 1392 else if (!name) 1393 name = "unknown"; 1394 audit_iface(profile, NULL, name, info, e, error); 1395 aa_free_profile(profile); 1396 1397 return ERR_PTR(error); 1398 } 1399 1400 /** 1401 * verify_header - unpack serialized stream header 1402 * @e: serialized data read head (NOT NULL) 1403 * @required: whether the header is required or optional 1404 * @ns: Returns - namespace if one is specified else NULL (NOT NULL) 1405 * 1406 * Returns: error or 0 if header is good 1407 */ 1408 static int verify_header(struct aa_ext *e, int required, const char **ns) 1409 { 1410 int error = -EPROTONOSUPPORT; 1411 const char *name = NULL; 1412 *ns = NULL; 1413 1414 /* get the interface version */ 1415 if (!aa_unpack_u32(e, &e->version, "version")) { 1416 if (required) { 1417 audit_iface(NULL, NULL, NULL, "invalid profile format", 1418 e, error); 1419 return error; 1420 } 1421 } 1422 1423 /* Check that the interface version is currently supported. 1424 * if not specified use previous version 1425 * Mask off everything that is not kernel abi version 1426 */ 1427 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v9)) { 1428 audit_iface(NULL, NULL, NULL, "unsupported interface version", 1429 e, error); 1430 return error; 1431 } 1432 1433 /* read the namespace if present */ 1434 if (aa_unpack_str(e, &name, "namespace")) { 1435 if (*name == '\0') { 1436 audit_iface(NULL, NULL, NULL, "invalid namespace name", 1437 e, error); 1438 return error; 1439 } 1440 if (*ns && strcmp(*ns, name)) { 1441 audit_iface(NULL, NULL, NULL, "invalid ns change", e, 1442 error); 1443 } else if (!*ns) { 1444 *ns = kstrdup(name, GFP_KERNEL); 1445 if (!*ns) 1446 return -ENOMEM; 1447 } 1448 } 1449 1450 return 0; 1451 } 1452 1453 /** 1454 * verify_dfa_accept_index - verify accept indexes are in range of perms table 1455 * @dfa: the dfa to check accept indexes are in range 1456 * @table_size: the permission table size the indexes should be within 1457 */ 1458 static bool verify_dfa_accept_index(struct aa_dfa *dfa, int table_size) 1459 { 1460 int i; 1461 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) { 1462 if (ACCEPT_TABLE(dfa)[i] >= table_size) 1463 return false; 1464 } 1465 return true; 1466 } 1467 1468 static bool verify_perm(struct aa_perms *perm) 1469 { 1470 /* TODO: allow option to just force the perms into a valid state */ 1471 if (perm->allow & perm->deny) 1472 return false; 1473 if (perm->subtree & ~perm->allow) 1474 return false; 1475 if (perm->cond & (perm->allow | perm->deny)) 1476 return false; 1477 if (perm->kill & perm->allow) 1478 return false; 1479 if (perm->complain & (perm->allow | perm->deny)) 1480 return false; 1481 if (perm->prompt & (perm->allow | perm->deny)) 1482 return false; 1483 if (perm->complain & perm->prompt) 1484 return false; 1485 if (perm->hide & perm->allow) 1486 return false; 1487 1488 return true; 1489 } 1490 1491 static bool verify_perms(struct aa_policydb *pdb) 1492 { 1493 int i; 1494 int xidx, xmax = -1; 1495 1496 for (i = 0; i < pdb->size; i++) { 1497 if (!verify_perm(&pdb->perms[i])) 1498 return false; 1499 /* verify indexes into str table */ 1500 if ((pdb->perms[i].xindex & AA_X_TYPE_MASK) == AA_X_TABLE) { 1501 xidx = pdb->perms[i].xindex & AA_X_INDEX_MASK; 1502 if (xidx >= pdb->trans.size) 1503 return false; 1504 if (xmax < xidx) 1505 xmax = xidx; 1506 } 1507 if (pdb->perms[i].tag && pdb->perms[i].tag >= pdb->tags.sets.size) 1508 return false; 1509 if (pdb->perms[i].label && 1510 pdb->perms[i].label >= pdb->trans.size) 1511 return false; 1512 } 1513 /* deal with incorrectly constructed string tables */ 1514 if (xmax == -1) { 1515 aa_destroy_str_table(&pdb->trans); 1516 } else if (pdb->trans.size > xmax + 1) { 1517 if (!aa_resize_str_table(&pdb->trans, xmax + 1, GFP_KERNEL)) 1518 return false; 1519 } 1520 return true; 1521 } 1522 1523 /** 1524 * verify_profile - Do post unpack analysis to verify profile consistency 1525 * @profile: profile to verify (NOT NULL) 1526 * 1527 * Returns: 0 if passes verification else error 1528 * 1529 * This verification is post any unpack mapping or changes 1530 */ 1531 static int verify_profile(struct aa_profile *profile) 1532 { 1533 struct aa_ruleset *rules = profile->label.rules[0]; 1534 1535 if (!rules) 1536 return 0; 1537 1538 if (rules->file->dfa && !verify_dfa_accept_index(rules->file->dfa, 1539 rules->file->size)) { 1540 audit_iface(profile, NULL, NULL, 1541 "Unpack: file Invalid named transition", NULL, 1542 -EPROTO); 1543 return -EPROTO; 1544 } 1545 if (rules->policy->dfa && 1546 !verify_dfa_accept_index(rules->policy->dfa, rules->policy->size)) { 1547 audit_iface(profile, NULL, NULL, 1548 "Unpack: policy Invalid named transition", NULL, 1549 -EPROTO); 1550 return -EPROTO; 1551 } 1552 1553 if (!verify_perms(rules->file)) { 1554 audit_iface(profile, NULL, NULL, 1555 "Unpack: Invalid perm index", NULL, -EPROTO); 1556 return -EPROTO; 1557 } 1558 if (!verify_perms(rules->policy)) { 1559 audit_iface(profile, NULL, NULL, 1560 "Unpack: Invalid perm index", NULL, -EPROTO); 1561 return -EPROTO; 1562 } 1563 if (!verify_perms(profile->attach.xmatch)) { 1564 audit_iface(profile, NULL, NULL, 1565 "Unpack: Invalid perm index", NULL, -EPROTO); 1566 return -EPROTO; 1567 } 1568 1569 return 0; 1570 } 1571 1572 void aa_load_ent_free(struct aa_load_ent *ent) 1573 { 1574 if (ent) { 1575 aa_put_profile(ent->rename); 1576 aa_put_profile(ent->old); 1577 aa_put_profile(ent->new); 1578 kfree(ent->ns_name); 1579 kfree_sensitive(ent); 1580 } 1581 } 1582 1583 struct aa_load_ent *aa_load_ent_alloc(void) 1584 { 1585 struct aa_load_ent *ent = kzalloc_obj(*ent); 1586 if (ent) 1587 INIT_LIST_HEAD(&ent->list); 1588 return ent; 1589 } 1590 1591 static int compress_zstd(const char *src, size_t slen, char **dst, size_t *dlen) 1592 { 1593 #ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY 1594 const zstd_parameters params = 1595 zstd_get_params(aa_g_rawdata_compression_level, slen); 1596 const size_t wksp_len = zstd_cctx_workspace_bound(¶ms.cParams); 1597 void *wksp = NULL; 1598 zstd_cctx *ctx = NULL; 1599 size_t out_len = zstd_compress_bound(slen); 1600 void *out = NULL; 1601 int ret = 0; 1602 1603 out = kvzalloc(out_len, GFP_KERNEL); 1604 if (!out) { 1605 ret = -ENOMEM; 1606 goto cleanup; 1607 } 1608 1609 wksp = kvzalloc(wksp_len, GFP_KERNEL); 1610 if (!wksp) { 1611 ret = -ENOMEM; 1612 goto cleanup; 1613 } 1614 1615 ctx = zstd_init_cctx(wksp, wksp_len); 1616 if (!ctx) { 1617 ret = -EINVAL; 1618 goto cleanup; 1619 } 1620 1621 out_len = zstd_compress_cctx(ctx, out, out_len, src, slen, ¶ms); 1622 if (zstd_is_error(out_len) || out_len >= slen) { 1623 ret = -EINVAL; 1624 goto cleanup; 1625 } 1626 1627 if (is_vmalloc_addr(out)) { 1628 *dst = kvzalloc(out_len, GFP_KERNEL); 1629 if (*dst) { 1630 memcpy(*dst, out, out_len); 1631 kvfree(out); 1632 out = NULL; 1633 } 1634 } else { 1635 /* 1636 * If the staging buffer was kmalloc'd, then using krealloc is 1637 * probably going to be faster. The destination buffer will 1638 * always be smaller, so it's just shrunk, avoiding a memcpy 1639 */ 1640 *dst = krealloc(out, out_len, GFP_KERNEL); 1641 } 1642 1643 if (!*dst) { 1644 ret = -ENOMEM; 1645 goto cleanup; 1646 } 1647 1648 *dlen = out_len; 1649 1650 cleanup: 1651 if (ret) { 1652 kvfree(out); 1653 *dst = NULL; 1654 } 1655 1656 kvfree(wksp); 1657 return ret; 1658 #else 1659 *dlen = slen; 1660 return 0; 1661 #endif 1662 } 1663 1664 static int compress_loaddata(struct aa_loaddata *data) 1665 { 1666 AA_BUG(data->compressed_size > 0); 1667 1668 /* 1669 * Shortcut the no compression case, else we increase the amount of 1670 * storage required by a small amount 1671 */ 1672 if (aa_g_rawdata_compression_level != 0) { 1673 void *udata = data->data; 1674 int error = compress_zstd(udata, data->size, &data->data, 1675 &data->compressed_size); 1676 if (error) { 1677 data->compressed_size = data->size; 1678 return error; 1679 } 1680 if (udata != data->data) 1681 kvfree(udata); 1682 } else 1683 data->compressed_size = data->size; 1684 1685 return 0; 1686 } 1687 1688 /** 1689 * aa_unpack - unpack packed binary profile(s) data loaded from user space 1690 * @udata: user data copied to kmem (NOT NULL) 1691 * @lh: list to place unpacked profiles in a aa_repl_ws 1692 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL) 1693 * 1694 * Unpack user data and return refcounted allocated profile(s) stored in 1695 * @lh in order of discovery, with the list chain stored in base.list 1696 * or error 1697 * 1698 * Returns: profile(s) on @lh else error pointer if fails to unpack 1699 */ 1700 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh, 1701 const char **ns) 1702 { 1703 struct aa_load_ent *tmp, *ent; 1704 struct aa_profile *profile = NULL; 1705 char *ns_name = NULL; 1706 int error; 1707 struct aa_ext e = { 1708 .start = udata->data, 1709 .end = udata->data + udata->size, 1710 .pos = udata->data, 1711 }; 1712 1713 *ns = NULL; 1714 while (e.pos < e.end) { 1715 void *start; 1716 error = verify_header(&e, e.pos == e.start, ns); 1717 if (error) 1718 goto fail; 1719 1720 start = e.pos; 1721 profile = unpack_profile(&e, &ns_name); 1722 if (IS_ERR(profile)) { 1723 error = PTR_ERR(profile); 1724 goto fail; 1725 } 1726 1727 error = verify_profile(profile); 1728 if (error) 1729 goto fail_profile; 1730 1731 if (aa_g_hash_policy) 1732 error = aa_calc_profile_hash(profile, e.version, start, 1733 e.pos - start); 1734 if (error) 1735 goto fail_profile; 1736 1737 ent = aa_load_ent_alloc(); 1738 if (!ent) { 1739 error = -ENOMEM; 1740 goto fail_profile; 1741 } 1742 1743 ent->new = profile; 1744 ent->ns_name = ns_name; 1745 ns_name = NULL; 1746 list_add_tail(&ent->list, lh); 1747 } 1748 udata->abi = e.version & K_ABI_MASK; 1749 if (aa_g_hash_policy) { 1750 udata->hash = aa_calc_hash(udata->data, udata->size); 1751 if (IS_ERR(udata->hash)) { 1752 error = PTR_ERR(udata->hash); 1753 udata->hash = NULL; 1754 goto fail; 1755 } 1756 } 1757 1758 if (aa_g_export_binary) { 1759 error = compress_loaddata(udata); 1760 if (error) 1761 goto fail; 1762 } 1763 return 0; 1764 1765 fail_profile: 1766 kfree(ns_name); 1767 aa_put_profile(profile); 1768 1769 fail: 1770 list_for_each_entry_safe(ent, tmp, lh, list) { 1771 list_del_init(&ent->list); 1772 aa_load_ent_free(ent); 1773 } 1774 1775 return error; 1776 } 1777