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 static void do_loaddata_free(struct aa_loaddata *d) 113 { 114 kfree_sensitive(d->hash); 115 kfree_sensitive(d->name); 116 kvfree(d->data); 117 kfree_sensitive(d); 118 } 119 120 void aa_loaddata_kref(struct kref *kref) 121 { 122 struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count); 123 124 do_loaddata_free(d); 125 } 126 127 /* 128 * need to take the ns mutex lock which is NOT safe most places that 129 * put_loaddata is called, so we have to delay freeing it 130 */ 131 static void do_ploaddata_rmfs(struct work_struct *work) 132 { 133 struct aa_loaddata *d = container_of(work, struct aa_loaddata, work); 134 struct aa_ns *ns = aa_get_ns(d->ns); 135 136 if (ns) { 137 mutex_lock_nested(&ns->lock, ns->level); 138 /* remove fs ref to loaddata */ 139 __aa_fs_remove_rawdata(d); 140 mutex_unlock(&ns->lock); 141 aa_put_ns(ns); 142 } 143 /* called by dropping last pcount, so drop its associated icount */ 144 aa_put_i_loaddata(d); 145 } 146 147 void aa_ploaddata_kref(struct kref *kref) 148 { 149 struct aa_loaddata *d = container_of(kref, struct aa_loaddata, pcount); 150 151 if (d) { 152 INIT_WORK(&d->work, do_ploaddata_rmfs); 153 schedule_work(&d->work); 154 } 155 } 156 157 struct aa_loaddata *aa_loaddata_alloc(size_t size) 158 { 159 struct aa_loaddata *d; 160 161 d = kzalloc_obj(*d); 162 if (d == NULL) 163 return ERR_PTR(-ENOMEM); 164 d->data = kvzalloc(size, GFP_KERNEL); 165 if (!d->data) { 166 kfree(d); 167 return ERR_PTR(-ENOMEM); 168 } 169 kref_init(&d->count); 170 kref_init(&d->pcount); 171 INIT_LIST_HEAD(&d->list); 172 173 return d; 174 } 175 176 /* test if read will be in packed data bounds */ 177 VISIBLE_IF_KUNIT bool aa_inbounds(struct aa_ext *e, size_t size) 178 { 179 return (size <= e->end - e->pos); 180 } 181 EXPORT_SYMBOL_IF_KUNIT(aa_inbounds); 182 183 /** 184 * aa_unpack_u16_chunk - test and do bounds checking for a u16 size based chunk 185 * @e: serialized data read head (NOT NULL) 186 * @chunk: start address for chunk of data (NOT NULL) 187 * 188 * Returns: the size of chunk found with the read head at the end of the chunk. 189 */ 190 VISIBLE_IF_KUNIT size_t aa_unpack_u16_chunk(struct aa_ext *e, char **chunk) 191 { 192 size_t size = 0; 193 void *pos = e->pos; 194 195 if (!aa_inbounds(e, sizeof(u16))) 196 goto fail; 197 size = le16_to_cpu(get_unaligned((__le16 *) e->pos)); 198 e->pos += sizeof(__le16); 199 if (!aa_inbounds(e, size)) 200 goto fail; 201 *chunk = e->pos; 202 e->pos += size; 203 return size; 204 205 fail: 206 e->pos = pos; 207 return 0; 208 } 209 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u16_chunk); 210 211 /* unpack control byte */ 212 VISIBLE_IF_KUNIT bool aa_unpack_X(struct aa_ext *e, enum aa_code code) 213 { 214 if (!aa_inbounds(e, 1)) 215 return false; 216 if (*(u8 *) e->pos != code) 217 return false; 218 e->pos++; 219 return true; 220 } 221 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_X); 222 223 /** 224 * aa_unpack_nameX - check is the next element is of type X with a name of @name 225 * @e: serialized data extent information (NOT NULL) 226 * @code: type code 227 * @name: name to match to the serialized element. (MAYBE NULL) 228 * 229 * check that the next serialized data element is of type X and has a tag 230 * name @name. If @name is specified then there must be a matching 231 * name element in the stream. If @name is NULL any name element will be 232 * skipped and only the typecode will be tested. 233 * 234 * Returns true on success (both type code and name tests match) and the read 235 * head is advanced past the headers 236 * 237 * Returns: false if either match fails, the read head does not move 238 */ 239 VISIBLE_IF_KUNIT bool aa_unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name) 240 { 241 /* 242 * May need to reset pos if name or type doesn't match 243 */ 244 void *pos = e->pos; 245 /* 246 * Check for presence of a tagname, and if present name size 247 * AA_NAME tag value is a u16. 248 */ 249 if (aa_unpack_X(e, AA_NAME)) { 250 char *tag = NULL; 251 size_t size = aa_unpack_u16_chunk(e, &tag); 252 /* if a name is specified it must match. otherwise skip tag */ 253 if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag))) 254 goto fail; 255 } else if (name) { 256 /* if a name is specified and there is no name tag fail */ 257 goto fail; 258 } 259 260 /* now check if type code matches */ 261 if (aa_unpack_X(e, code)) 262 return true; 263 264 fail: 265 e->pos = pos; 266 return false; 267 } 268 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_nameX); 269 270 static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name) 271 { 272 void *pos = e->pos; 273 274 if (aa_unpack_nameX(e, AA_U8, name)) { 275 if (!aa_inbounds(e, sizeof(u8))) 276 goto fail; 277 if (data) 278 *data = *((u8 *)e->pos); 279 e->pos += sizeof(u8); 280 return true; 281 } 282 283 fail: 284 e->pos = pos; 285 return false; 286 } 287 288 VISIBLE_IF_KUNIT bool aa_unpack_u32(struct aa_ext *e, u32 *data, const char *name) 289 { 290 void *pos = e->pos; 291 292 if (aa_unpack_nameX(e, AA_U32, name)) { 293 if (!aa_inbounds(e, sizeof(u32))) 294 goto fail; 295 if (data) 296 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos)); 297 e->pos += sizeof(u32); 298 return true; 299 } 300 301 fail: 302 e->pos = pos; 303 return false; 304 } 305 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u32); 306 307 VISIBLE_IF_KUNIT bool aa_unpack_u64(struct aa_ext *e, u64 *data, const char *name) 308 { 309 void *pos = e->pos; 310 311 if (aa_unpack_nameX(e, AA_U64, name)) { 312 if (!aa_inbounds(e, sizeof(u64))) 313 goto fail; 314 if (data) 315 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos)); 316 e->pos += sizeof(u64); 317 return true; 318 } 319 320 fail: 321 e->pos = pos; 322 return false; 323 } 324 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u64); 325 326 static bool aa_unpack_cap_low(struct aa_ext *e, kernel_cap_t *data, const char *name) 327 { 328 u32 val; 329 330 if (!aa_unpack_u32(e, &val, name)) 331 return false; 332 data->val = val; 333 return true; 334 } 335 336 static bool aa_unpack_cap_high(struct aa_ext *e, kernel_cap_t *data, const char *name) 337 { 338 u32 val; 339 340 if (!aa_unpack_u32(e, &val, name)) 341 return false; 342 data->val = (u32)data->val | ((u64)val << 32); 343 return true; 344 } 345 346 VISIBLE_IF_KUNIT bool aa_unpack_array(struct aa_ext *e, const char *name, u16 *size) 347 { 348 void *pos = e->pos; 349 350 if (aa_unpack_nameX(e, AA_ARRAY, name)) { 351 if (!aa_inbounds(e, sizeof(u16))) 352 goto fail; 353 *size = le16_to_cpu(get_unaligned((__le16 *) e->pos)); 354 e->pos += sizeof(u16); 355 return true; 356 } 357 358 fail: 359 e->pos = pos; 360 return false; 361 } 362 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_array); 363 364 VISIBLE_IF_KUNIT size_t aa_unpack_blob(struct aa_ext *e, char **blob, const char *name) 365 { 366 void *pos = e->pos; 367 368 if (aa_unpack_nameX(e, AA_BLOB, name)) { 369 u32 size; 370 if (!aa_inbounds(e, sizeof(u32))) 371 goto fail; 372 size = le32_to_cpu(get_unaligned((__le32 *) e->pos)); 373 e->pos += sizeof(u32); 374 if (aa_inbounds(e, (size_t) size)) { 375 *blob = e->pos; 376 e->pos += size; 377 return size; 378 } 379 } 380 381 fail: 382 e->pos = pos; 383 return 0; 384 } 385 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_blob); 386 387 VISIBLE_IF_KUNIT int aa_unpack_str(struct aa_ext *e, const char **string, const char *name) 388 { 389 char *src_str; 390 size_t size = 0; 391 void *pos = e->pos; 392 *string = NULL; 393 if (aa_unpack_nameX(e, AA_STRING, name)) { 394 size = aa_unpack_u16_chunk(e, &src_str); 395 if (size) { 396 /* strings are null terminated, length is size - 1 */ 397 if (src_str[size - 1] != 0) 398 goto fail; 399 *string = src_str; 400 401 return size; 402 } 403 } 404 405 fail: 406 e->pos = pos; 407 return 0; 408 } 409 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_str); 410 411 VISIBLE_IF_KUNIT int aa_unpack_strdup(struct aa_ext *e, char **string, const char *name) 412 { 413 const char *tmp; 414 void *pos = e->pos; 415 int res = aa_unpack_str(e, &tmp, name); 416 *string = NULL; 417 418 if (!res) 419 return 0; 420 421 *string = kmemdup(tmp, res, GFP_KERNEL); 422 if (!*string) { 423 e->pos = pos; 424 return 0; 425 } 426 427 return res; 428 } 429 EXPORT_SYMBOL_IF_KUNIT(aa_unpack_strdup); 430 431 432 /** 433 * unpack_dfa - unpack a file rule dfa 434 * @e: serialized data extent information (NOT NULL) 435 * @flags: dfa flags to check 436 * 437 * returns dfa or ERR_PTR or NULL if no dfa 438 */ 439 static struct aa_dfa *unpack_dfa(struct aa_ext *e, int flags) 440 { 441 char *blob = NULL; 442 size_t size; 443 struct aa_dfa *dfa = NULL; 444 445 size = aa_unpack_blob(e, &blob, "aadfa"); 446 if (size) { 447 /* 448 * The dfa is aligned with in the blob to 8 bytes 449 * from the beginning of the stream. 450 * alignment adjust needed by dfa unpack 451 */ 452 size_t sz = blob - (char *) e->start - 453 ((e->pos - e->start) & 7); 454 size_t pad = ALIGN(sz, 8) - sz; 455 if (aa_g_paranoid_load) 456 flags |= DFA_FLAG_VERIFY_STATES; 457 dfa = aa_dfa_unpack(blob + pad, size - pad, flags); 458 459 if (IS_ERR(dfa)) 460 return dfa; 461 462 } 463 464 return dfa; 465 } 466 467 static int process_strs_entry(char *str, int size, bool multi) 468 { 469 int c = 1; 470 471 if (size <= 0) 472 return -1; 473 if (multi) { 474 if (size < 2) 475 return -2; 476 /* multi ends with double \0 */ 477 if (str[size - 2]) 478 return -3; 479 } 480 481 char *save = str; 482 char *pos = str; 483 char *end = multi ? str + size - 2 : str + size - 1; 484 /* count # of internal \0 */ 485 while (str < end) { 486 if (str == pos) { 487 /* starts with ... */ 488 if (!*str) { 489 AA_DEBUG(DEBUG_UNPACK, 490 "starting with null save=%lu size %d c=%d", 491 (unsigned long)(str - save), size, c); 492 return -4; 493 } 494 if (isspace(*str)) 495 return -5; 496 if (*str == ':') { 497 /* :ns_str\0str\0 498 * first character after : must be valid 499 */ 500 if (!str[1]) 501 return -6; 502 } 503 } else if (!*str) { 504 if (*pos == ':') 505 *str = ':'; 506 else 507 c++; 508 pos = str + 1; 509 } 510 str++; 511 } /* while */ 512 513 return c; 514 } 515 516 /** 517 * unpack_strs_table - unpack a profile transition table 518 * @e: serialized data extent information (NOT NULL) 519 * @name: name of table (MAY BE NULL) 520 * @multi: allow multiple strings on a single entry 521 * @strs: str table to unpack to (NOT NULL) 522 * 523 * Returns: 0 if table successfully unpacked or not present, else error 524 */ 525 static int unpack_strs_table(struct aa_ext *e, const char *name, bool multi, 526 struct aa_str_table *strs) 527 { 528 void *saved_pos = e->pos; 529 struct aa_str_table_ent *table = NULL; 530 int error = -EPROTO; 531 532 /* exec table is optional */ 533 if (aa_unpack_nameX(e, AA_STRUCT, name)) { 534 u16 size; 535 int i; 536 537 if (!aa_unpack_array(e, NULL, &size)) 538 /* 539 * Note: index into trans table array is a max 540 * of 2^24, but unpack array can only unpack 541 * an array of 2^16 in size atm so no need 542 * for size check here 543 */ 544 goto fail; 545 table = kzalloc_objs(struct aa_str_table_ent, size); 546 if (!table) { 547 error = -ENOMEM; 548 goto fail; 549 } 550 strs->table = table; 551 strs->size = size; 552 for (i = 0; i < size; i++) { 553 char *str; 554 int c, size2 = aa_unpack_strdup(e, &str, NULL); 555 /* aa_unpack_strdup verifies that the last character is 556 * null termination byte. 557 */ 558 c = process_strs_entry(str, size2, multi); 559 if (c <= 0) { 560 AA_DEBUG(DEBUG_UNPACK, "process_strs %d i %d pos %ld", 561 c, i, 562 (unsigned long)(e->pos - saved_pos)); 563 goto fail; 564 } 565 if (!multi && c > 1) { 566 AA_DEBUG(DEBUG_UNPACK, "!multi && c > 1"); 567 /* fail - all other cases with embedded \0 */ 568 goto fail; 569 } 570 table[i].strs = str; 571 table[i].count = c; 572 table[i].size = size2; 573 } 574 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 575 goto fail; 576 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 577 goto fail; 578 } 579 return 0; 580 581 fail: 582 aa_destroy_str_table(strs); 583 e->pos = saved_pos; 584 return error; 585 } 586 587 static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile) 588 { 589 void *pos = e->pos; 590 591 if (aa_unpack_nameX(e, AA_STRUCT, "xattrs")) { 592 u16 size; 593 int i; 594 595 if (!aa_unpack_array(e, NULL, &size)) 596 goto fail; 597 profile->attach.xattr_count = size; 598 profile->attach.xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL); 599 if (!profile->attach.xattrs) 600 goto fail; 601 for (i = 0; i < size; i++) { 602 if (!aa_unpack_strdup(e, &profile->attach.xattrs[i], NULL)) 603 goto fail; 604 } 605 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 606 goto fail; 607 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 608 goto fail; 609 } 610 611 return true; 612 613 fail: 614 e->pos = pos; 615 return false; 616 } 617 618 static bool unpack_secmark(struct aa_ext *e, struct aa_ruleset *rules) 619 { 620 void *pos = e->pos; 621 u16 size; 622 int i; 623 624 if (aa_unpack_nameX(e, AA_STRUCT, "secmark")) { 625 if (!aa_unpack_array(e, NULL, &size)) 626 goto fail; 627 628 rules->secmark = kzalloc_objs(struct aa_secmark, size); 629 if (!rules->secmark) 630 goto fail; 631 632 rules->secmark_count = size; 633 634 for (i = 0; i < size; i++) { 635 if (!unpack_u8(e, &rules->secmark[i].audit, NULL)) 636 goto fail; 637 if (!unpack_u8(e, &rules->secmark[i].deny, NULL)) 638 goto fail; 639 if (!aa_unpack_strdup(e, &rules->secmark[i].label, NULL)) 640 goto fail; 641 } 642 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 643 goto fail; 644 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 645 goto fail; 646 } 647 648 return true; 649 650 fail: 651 if (rules->secmark) { 652 for (i = 0; i < size; i++) 653 kfree_sensitive(rules->secmark[i].label); 654 kfree_sensitive(rules->secmark); 655 rules->secmark_count = 0; 656 rules->secmark = NULL; 657 } 658 659 e->pos = pos; 660 return false; 661 } 662 663 static bool unpack_rlimits(struct aa_ext *e, struct aa_ruleset *rules) 664 { 665 void *pos = e->pos; 666 667 /* rlimits are optional */ 668 if (aa_unpack_nameX(e, AA_STRUCT, "rlimits")) { 669 u16 size; 670 int i; 671 u32 tmp = 0; 672 if (!aa_unpack_u32(e, &tmp, NULL)) 673 goto fail; 674 rules->rlimits.mask = tmp; 675 676 if (!aa_unpack_array(e, NULL, &size) || 677 size > RLIM_NLIMITS) 678 goto fail; 679 for (i = 0; i < size; i++) { 680 u64 tmp2 = 0; 681 int a = aa_map_resource(i); 682 if (!aa_unpack_u64(e, &tmp2, NULL)) 683 goto fail; 684 rules->rlimits.limits[a].rlim_max = tmp2; 685 } 686 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 687 goto fail; 688 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 689 goto fail; 690 } 691 return true; 692 693 fail: 694 e->pos = pos; 695 return false; 696 } 697 698 699 static bool verify_tags(struct aa_tags_struct *tags, const char **info) 700 { 701 if ((tags->hdrs.size && !tags->hdrs.table) || 702 (!tags->hdrs.size && tags->hdrs.table)) { 703 *info = "failed verification tag.hdrs disagree"; 704 return false; 705 } 706 if ((tags->sets.size && !tags->sets.table) || 707 (!tags->sets.size && tags->sets.table)) { 708 *info = "failed verification tag.sets disagree"; 709 return false; 710 } 711 if ((tags->strs.size && !tags->strs.table) || 712 (!tags->strs.size && tags->strs.table)) { 713 *info = "failed verification tags->strs disagree"; 714 return false; 715 } 716 /* no data present */ 717 if (!tags->sets.size && !tags->hdrs.size && !tags->strs.size) { 718 return true; 719 } else if (!(tags->sets.size && tags->hdrs.size && tags->strs.size)) { 720 /* some data present but not all */ 721 *info = "failed verification tags partial data present"; 722 return false; 723 } 724 725 u32 i; 726 727 for (i = 0; i < tags->sets.size; i++) { 728 /* count followed by count indexes into hdrs */ 729 u32 cnt = tags->sets.table[i]; 730 731 if (i+cnt >= tags->sets.size) { 732 AA_DEBUG(DEBUG_UNPACK, 733 "tagset too large %d+%d > sets.table[%d]", 734 i, cnt, tags->sets.size); 735 *info = "failed verification tagset too large"; 736 return false; 737 } 738 for (; cnt; cnt--) { 739 if (tags->sets.table[++i] >= tags->hdrs.size) { 740 AA_DEBUG(DEBUG_UNPACK, 741 "tagsets idx out of bounds cnt %d sets.table[%d] >= %d", 742 cnt, i-1, tags->hdrs.size); 743 *info = "failed verification tagsets idx out of bounds"; 744 return false; 745 } 746 } 747 } 748 for (i = 0; i < tags->hdrs.size; i++) { 749 u32 idx = tags->hdrs.table[i].tags; 750 751 if (idx >= tags->strs.size) { 752 AA_DEBUG(DEBUG_UNPACK, 753 "tag.hdrs idx oob idx %d > tags->strs.size=%d", 754 idx, tags->strs.size); 755 *info = "failed verification tags.hdrs idx out of bounds"; 756 return false; 757 } 758 if (tags->hdrs.table[i].count != tags->strs.table[idx].count) { 759 AA_DEBUG(DEBUG_UNPACK, "hdrs.table[%d].count=%d != tags->strs.table[%d]=%d", 760 i, tags->hdrs.table[i].count, idx, tags->strs.table[idx].count); 761 *info = "failed verification tagd.hdrs[idx].count"; 762 return false; 763 } 764 if (tags->hdrs.table[i].size != tags->strs.table[idx].size) { 765 AA_DEBUG(DEBUG_UNPACK, "hdrs.table[%d].size=%d != strs.table[%d].size=%d", 766 i, tags->hdrs.table[i].size, idx, tags->strs.table[idx].size); 767 *info = "failed verification tagd.hdrs[idx].size"; 768 return false; 769 } 770 } 771 772 return true; 773 } 774 775 static int unpack_tagsets(struct aa_ext *e, struct aa_tags_struct *tags) 776 { 777 u32 *sets; 778 u16 i, size; 779 int error = -EPROTO; 780 void *pos = e->pos; 781 782 if (!aa_unpack_array(e, "sets", &size)) 783 goto fail_reset; 784 sets = kcalloc(size, sizeof(u32), GFP_KERNEL); 785 if (!sets) { 786 error = -ENOMEM; 787 goto fail_reset; 788 } 789 for (i = 0; i < size; i++) { 790 if (!aa_unpack_u32(e, &sets[i], NULL)) 791 goto fail; 792 } 793 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 794 goto fail; 795 796 tags->sets.size = size; 797 tags->sets.table = sets; 798 799 return 0; 800 801 fail: 802 kfree_sensitive(sets); 803 fail_reset: 804 e->pos = pos; 805 return error; 806 } 807 808 static bool unpack_tag_header_ent(struct aa_ext *e, struct aa_tags_header *h) 809 { 810 return aa_unpack_u32(e, &h->mask, NULL) && 811 aa_unpack_u32(e, &h->count, NULL) && 812 aa_unpack_u32(e, &h->size, NULL) && 813 aa_unpack_u32(e, &h->tags, NULL); 814 } 815 816 static int unpack_tag_headers(struct aa_ext *e, struct aa_tags_struct *tags) 817 { 818 struct aa_tags_header *hdrs; 819 u16 i, size; 820 int error = -EPROTO; 821 void *pos = e->pos; 822 823 if (!aa_unpack_array(e, "hdrs", &size)) 824 goto fail_reset; 825 hdrs = kzalloc_objs(struct aa_tags_header, size); 826 if (!hdrs) { 827 error = -ENOMEM; 828 goto fail_reset; 829 } 830 for (i = 0; i < size; i++) { 831 if (!unpack_tag_header_ent(e, &hdrs[i])) 832 goto fail; 833 } 834 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 835 goto fail; 836 837 tags->hdrs.size = size; 838 tags->hdrs.table = hdrs; 839 AA_DEBUG(DEBUG_UNPACK, "headers %ld size %d", (long) hdrs, size); 840 return true; 841 842 fail: 843 kfree_sensitive(hdrs); 844 fail_reset: 845 e->pos = pos; 846 return error; 847 } 848 849 850 static int unpack_tags(struct aa_ext *e, struct aa_tags_struct *tags, 851 const char **info) 852 { 853 int error = -EPROTO; 854 void *pos = e->pos; 855 856 AA_BUG(!tags); 857 /* policy tags are optional */ 858 if (aa_unpack_nameX(e, AA_STRUCT, "tags")) { 859 u32 version; 860 861 if (!aa_unpack_u32(e, &version, "version") || version != 1) { 862 *info = "invalid tags version"; 863 goto fail_reset; 864 } 865 error = unpack_strs_table(e, "strs", true, &tags->strs); 866 if (error) { 867 *info = "failed to unpack profile tag.strs"; 868 goto fail; 869 } 870 error = unpack_tag_headers(e, tags); 871 if (error) { 872 *info = "failed to unpack profile tag.headers"; 873 goto fail; 874 } 875 error = unpack_tagsets(e, tags); 876 if (error) { 877 *info = "failed to unpack profile tag.sets"; 878 goto fail; 879 } 880 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 881 goto fail; 882 883 if (!verify_tags(tags, info)) 884 goto fail; 885 } 886 887 return 0; 888 889 fail: 890 aa_destroy_tags(tags); 891 fail_reset: 892 e->pos = pos; 893 return error; 894 } 895 896 static bool unpack_perm(struct aa_ext *e, u32 version, struct aa_perms *perm) 897 { 898 u32 reserved; 899 900 if (version != 1) 901 return false; 902 903 /* reserved entry is for later expansion, discard for now */ 904 return aa_unpack_u32(e, &reserved, NULL) && 905 aa_unpack_u32(e, &perm->allow, NULL) && 906 aa_unpack_u32(e, &perm->deny, NULL) && 907 aa_unpack_u32(e, &perm->subtree, NULL) && 908 aa_unpack_u32(e, &perm->cond, NULL) && 909 aa_unpack_u32(e, &perm->kill, NULL) && 910 aa_unpack_u32(e, &perm->complain, NULL) && 911 aa_unpack_u32(e, &perm->prompt, NULL) && 912 aa_unpack_u32(e, &perm->audit, NULL) && 913 aa_unpack_u32(e, &perm->quiet, NULL) && 914 aa_unpack_u32(e, &perm->hide, NULL) && 915 aa_unpack_u32(e, &perm->xindex, NULL) && 916 aa_unpack_u32(e, &perm->tag, NULL) && 917 aa_unpack_u32(e, &perm->label, NULL); 918 } 919 920 static ssize_t unpack_perms_table(struct aa_ext *e, struct aa_perms **perms) 921 { 922 void *pos = e->pos; 923 u16 size = 0; 924 925 AA_BUG(!perms); 926 /* 927 * policy perms are optional, in which case perms are embedded 928 * in the dfa accept table 929 */ 930 if (aa_unpack_nameX(e, AA_STRUCT, "perms")) { 931 int i; 932 u32 version; 933 934 if (!aa_unpack_u32(e, &version, "version")) 935 goto fail_reset; 936 if (!aa_unpack_array(e, NULL, &size)) 937 goto fail_reset; 938 *perms = kzalloc_objs(struct aa_perms, size); 939 if (!*perms) { 940 e->pos = pos; 941 return -ENOMEM; 942 } 943 for (i = 0; i < size; i++) { 944 if (!unpack_perm(e, version, &(*perms)[i])) 945 goto fail; 946 } 947 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) 948 goto fail; 949 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 950 goto fail; 951 } else 952 *perms = NULL; 953 954 return size; 955 956 fail: 957 kfree(*perms); 958 fail_reset: 959 e->pos = pos; 960 return -EPROTO; 961 } 962 963 static int unpack_pdb(struct aa_ext *e, struct aa_policydb **policy, 964 bool required_dfa, bool required_trans, 965 const char **info) 966 { 967 struct aa_policydb *pdb; 968 void *pos = e->pos; 969 int i, flags, error = -EPROTO; 970 ssize_t size; 971 u32 version = 0; 972 973 pdb = aa_alloc_pdb(GFP_KERNEL); 974 if (!pdb) 975 return -ENOMEM; 976 977 AA_DEBUG(DEBUG_UNPACK, "unpacking tags"); 978 if (unpack_tags(e, &pdb->tags, info) < 0) 979 goto fail; 980 AA_DEBUG(DEBUG_UNPACK, "done unpacking tags"); 981 982 size = unpack_perms_table(e, &pdb->perms); 983 if (size < 0) { 984 error = size; 985 pdb->perms = NULL; 986 *info = "failed to unpack - perms"; 987 goto fail; 988 } 989 pdb->size = size; 990 991 if (pdb->perms) { 992 /* perms table present accept is index */ 993 flags = TO_ACCEPT1_FLAG(YYTD_DATA32); 994 if (aa_unpack_u32(e, &version, "permsv") && version > 2) 995 /* accept2 used for dfa flags */ 996 flags |= TO_ACCEPT2_FLAG(YYTD_DATA32); 997 } else { 998 /* packed perms in accept1 and accept2 */ 999 flags = TO_ACCEPT1_FLAG(YYTD_DATA32) | 1000 TO_ACCEPT2_FLAG(YYTD_DATA32); 1001 } 1002 1003 pdb->dfa = unpack_dfa(e, flags); 1004 if (IS_ERR(pdb->dfa)) { 1005 error = PTR_ERR(pdb->dfa); 1006 pdb->dfa = NULL; 1007 *info = "failed to unpack - dfa"; 1008 goto fail; 1009 } else if (!pdb->dfa) { 1010 if (required_dfa) { 1011 *info = "missing required dfa"; 1012 goto fail; 1013 } 1014 } else { 1015 /* 1016 * only unpack the following if a dfa is present 1017 * 1018 * sadly start was given different names for file and policydb 1019 * but since it is optional we can try both 1020 */ 1021 if (!aa_unpack_u32(e, &pdb->start[0], "start")) 1022 /* default start state */ 1023 pdb->start[0] = DFA_START; 1024 if (!aa_unpack_u32(e, &pdb->start[AA_CLASS_FILE], "dfa_start")) { 1025 /* default start state for xmatch and file dfa */ 1026 pdb->start[AA_CLASS_FILE] = DFA_START; 1027 } 1028 1029 size_t state_count = pdb->dfa->tables[YYTD_ID_BASE]->td_lolen; 1030 1031 if (pdb->start[0] >= state_count || 1032 pdb->start[AA_CLASS_FILE] >= state_count) { 1033 *info = "invalid dfa start state"; 1034 goto fail; 1035 } 1036 1037 /* setup class index */ 1038 for (i = AA_CLASS_FILE + 1; i <= AA_CLASS_LAST; i++) { 1039 pdb->start[i] = aa_dfa_next(pdb->dfa, pdb->start[0], 1040 i); 1041 } 1042 } 1043 1044 /* accept2 is in some cases being allocated, even with perms */ 1045 if (pdb->perms && !pdb->dfa->tables[YYTD_ID_ACCEPT2]) { 1046 /* add dfa flags table missing in v2 */ 1047 u32 noents = pdb->dfa->tables[YYTD_ID_ACCEPT]->td_lolen; 1048 u16 tdflags = pdb->dfa->tables[YYTD_ID_ACCEPT]->td_flags; 1049 size_t tsize = table_size(noents, tdflags); 1050 1051 pdb->dfa->tables[YYTD_ID_ACCEPT2] = kvzalloc(tsize, GFP_KERNEL); 1052 if (!pdb->dfa->tables[YYTD_ID_ACCEPT2]) { 1053 *info = "failed to alloc dfa flags table"; 1054 goto out; 1055 } 1056 pdb->dfa->tables[YYTD_ID_ACCEPT2]->td_lolen = noents; 1057 pdb->dfa->tables[YYTD_ID_ACCEPT2]->td_flags = tdflags; 1058 } 1059 /* 1060 * Unfortunately due to a bug in earlier userspaces, a 1061 * transition table may be present even when the dfa is 1062 * not. For compatibility reasons unpack and discard. 1063 */ 1064 error = unpack_strs_table(e, "xtable", false, &pdb->trans); 1065 if (error && required_trans) { 1066 *info = "failed to unpack profile transition table"; 1067 goto fail; 1068 } 1069 1070 if (!pdb->dfa && pdb->trans.table) 1071 aa_destroy_str_table(&pdb->trans); 1072 1073 /* TODO: 1074 * - move compat mapping here, requires dfa merging first 1075 * - move verify here, it has to be done after compat mappings 1076 * - move free of unneeded trans table here, has to be done 1077 * after perm mapping. 1078 */ 1079 out: 1080 *policy = pdb; 1081 return 0; 1082 1083 fail: 1084 aa_put_pdb(pdb); 1085 e->pos = pos; 1086 return error; 1087 } 1088 1089 static u32 strhash(const void *data, u32 len, u32 seed) 1090 { 1091 const char * const *key = data; 1092 1093 return jhash(*key, strlen(*key), seed); 1094 } 1095 1096 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj) 1097 { 1098 const struct aa_data *data = obj; 1099 const char * const *key = arg->key; 1100 1101 return strcmp(data->key, *key); 1102 } 1103 1104 /** 1105 * unpack_profile - unpack a serialized profile 1106 * @e: serialized data extent information (NOT NULL) 1107 * @ns_name: pointer of newly allocated copy of %NULL in case of error 1108 * 1109 * NOTE: unpack profile sets audit struct if there is a failure 1110 */ 1111 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name) 1112 { 1113 struct aa_ruleset *rules; 1114 struct aa_profile *profile = NULL; 1115 const char *tmpname, *tmpns = NULL, *name = NULL; 1116 const char *info = "failed to unpack profile"; 1117 size_t ns_len; 1118 struct rhashtable_params params = { 0 }; 1119 char *key = NULL, *disconnected = NULL; 1120 struct aa_data *data; 1121 int error = -EPROTO; 1122 kernel_cap_t tmpcap; 1123 u32 tmp; 1124 1125 *ns_name = NULL; 1126 1127 /* check that we have the right struct being passed */ 1128 if (!aa_unpack_nameX(e, AA_STRUCT, "profile")) 1129 goto fail; 1130 if (!aa_unpack_str(e, &name, NULL)) 1131 goto fail; 1132 if (*name == '\0') 1133 goto fail; 1134 1135 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len); 1136 if (tmpns) { 1137 if (!tmpname) { 1138 info = "empty profile name"; 1139 goto fail; 1140 } 1141 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL); 1142 if (!*ns_name) { 1143 info = "out of memory"; 1144 error = -ENOMEM; 1145 goto fail; 1146 } 1147 name = tmpname; 1148 } 1149 1150 profile = aa_alloc_profile(name, NULL, GFP_KERNEL); 1151 if (!profile) { 1152 info = "out of memory"; 1153 error = -ENOMEM; 1154 goto fail; 1155 } 1156 rules = profile->label.rules[0]; 1157 1158 /* profile renaming is optional */ 1159 (void) aa_unpack_str(e, &profile->rename, "rename"); 1160 1161 /* attachment string is optional */ 1162 (void) aa_unpack_str(e, &profile->attach.xmatch_str, "attach"); 1163 1164 /* xmatch is optional and may be NULL */ 1165 error = unpack_pdb(e, &profile->attach.xmatch, false, false, &info); 1166 if (error) { 1167 info = "bad xmatch"; 1168 goto fail; 1169 } 1170 1171 /* neither xmatch_len not xmatch_perms are optional if xmatch is set */ 1172 if (profile->attach.xmatch->dfa) { 1173 if (!aa_unpack_u32(e, &tmp, NULL)) { 1174 info = "missing xmatch len"; 1175 goto fail; 1176 } 1177 profile->attach.xmatch_len = tmp; 1178 profile->attach.xmatch->start[AA_CLASS_XMATCH] = DFA_START; 1179 if (!profile->attach.xmatch->perms) { 1180 error = aa_compat_map_xmatch(profile->attach.xmatch); 1181 if (error) { 1182 info = "failed to convert xmatch permission table"; 1183 goto fail; 1184 } 1185 } 1186 } 1187 1188 /* disconnected attachment string is optional */ 1189 (void) aa_unpack_strdup(e, &disconnected, "disconnected"); 1190 profile->disconnected = disconnected; 1191 1192 /* optional */ 1193 (void) aa_unpack_u32(e, &profile->signal, "kill"); 1194 if (profile->signal < 1 || profile->signal > MAXMAPPED_SIG) { 1195 info = "profile kill.signal invalid value"; 1196 goto fail; 1197 } 1198 /* per profile debug flags (complain, audit) */ 1199 if (!aa_unpack_nameX(e, AA_STRUCT, "flags")) { 1200 info = "profile missing flags"; 1201 goto fail; 1202 } 1203 info = "failed to unpack profile flags"; 1204 if (!aa_unpack_u32(e, &tmp, NULL)) 1205 goto fail; 1206 if (tmp & PACKED_FLAG_HAT) 1207 profile->label.flags |= FLAG_HAT; 1208 if (tmp & PACKED_FLAG_DEBUG1) 1209 profile->label.flags |= FLAG_DEBUG1; 1210 if (tmp & PACKED_FLAG_DEBUG2) 1211 profile->label.flags |= FLAG_DEBUG2; 1212 if (!aa_unpack_u32(e, &tmp, NULL)) 1213 goto fail; 1214 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG)) { 1215 profile->mode = APPARMOR_COMPLAIN; 1216 } else if (tmp == PACKED_MODE_ENFORCE) { 1217 profile->mode = APPARMOR_ENFORCE; 1218 } else if (tmp == PACKED_MODE_KILL) { 1219 profile->mode = APPARMOR_KILL; 1220 } else if (tmp == PACKED_MODE_UNCONFINED) { 1221 profile->mode = APPARMOR_UNCONFINED; 1222 profile->label.flags |= FLAG_UNCONFINED; 1223 } else if (tmp == PACKED_MODE_USER) { 1224 profile->mode = APPARMOR_USER; 1225 } else { 1226 goto fail; 1227 } 1228 if (!aa_unpack_u32(e, &tmp, NULL)) 1229 goto fail; 1230 if (tmp) 1231 profile->audit = AUDIT_ALL; 1232 1233 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 1234 goto fail; 1235 1236 /* path_flags is optional */ 1237 if (aa_unpack_u32(e, &profile->path_flags, "path_flags")) 1238 profile->path_flags |= profile->label.flags & 1239 PATH_MEDIATE_DELETED; 1240 else 1241 /* set a default value if path_flags field is not present */ 1242 profile->path_flags = PATH_MEDIATE_DELETED; 1243 1244 info = "failed to unpack profile capabilities"; 1245 if (!aa_unpack_cap_low(e, &rules->caps.allow, NULL)) 1246 goto fail; 1247 if (!aa_unpack_cap_low(e, &rules->caps.audit, NULL)) 1248 goto fail; 1249 if (!aa_unpack_cap_low(e, &rules->caps.quiet, NULL)) 1250 goto fail; 1251 if (!aa_unpack_cap_low(e, &tmpcap, NULL)) 1252 goto fail; 1253 1254 info = "failed to unpack upper profile capabilities"; 1255 if (aa_unpack_nameX(e, AA_STRUCT, "caps64")) { 1256 /* optional upper half of 64 bit caps */ 1257 if (!aa_unpack_cap_high(e, &rules->caps.allow, NULL)) 1258 goto fail; 1259 if (!aa_unpack_cap_high(e, &rules->caps.audit, NULL)) 1260 goto fail; 1261 if (!aa_unpack_cap_high(e, &rules->caps.quiet, NULL)) 1262 goto fail; 1263 if (!aa_unpack_cap_high(e, &tmpcap, NULL)) 1264 goto fail; 1265 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 1266 goto fail; 1267 } 1268 1269 info = "failed to unpack extended profile capabilities"; 1270 if (aa_unpack_nameX(e, AA_STRUCT, "capsx")) { 1271 /* optional extended caps mediation mask */ 1272 if (!aa_unpack_cap_low(e, &rules->caps.extended, NULL)) 1273 goto fail; 1274 if (!aa_unpack_cap_high(e, &rules->caps.extended, NULL)) 1275 goto fail; 1276 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 1277 goto fail; 1278 } 1279 1280 if (!unpack_xattrs(e, profile)) { 1281 info = "failed to unpack profile xattrs"; 1282 goto fail; 1283 } 1284 1285 if (!unpack_rlimits(e, rules)) { 1286 info = "failed to unpack profile rlimits"; 1287 goto fail; 1288 } 1289 1290 if (!unpack_secmark(e, rules)) { 1291 info = "failed to unpack profile secmark rules"; 1292 goto fail; 1293 } 1294 1295 if (aa_unpack_nameX(e, AA_STRUCT, "policydb")) { 1296 /* generic policy dfa - optional and may be NULL */ 1297 info = "failed to unpack policydb"; 1298 error = unpack_pdb(e, &rules->policy, true, false, 1299 &info); 1300 if (error) 1301 goto fail; 1302 /* Fixup: drop when we get rid of start array */ 1303 if (aa_dfa_next(rules->policy->dfa, rules->policy->start[0], 1304 AA_CLASS_FILE)) 1305 rules->policy->start[AA_CLASS_FILE] = 1306 aa_dfa_next(rules->policy->dfa, 1307 rules->policy->start[0], 1308 AA_CLASS_FILE); 1309 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) 1310 goto fail; 1311 if (!rules->policy->perms) { 1312 error = aa_compat_map_policy(rules->policy, 1313 e->version); 1314 if (error) { 1315 info = "failed to remap policydb permission table"; 1316 goto fail; 1317 } 1318 } 1319 } else { 1320 rules->policy = aa_get_pdb(nullpdb); 1321 } 1322 /* get file rules */ 1323 error = unpack_pdb(e, &rules->file, false, true, &info); 1324 if (error) { 1325 goto fail; 1326 } else if (rules->file->dfa) { 1327 if (!rules->file->perms) { 1328 AA_DEBUG(DEBUG_UNPACK, "compat mapping perms"); 1329 error = aa_compat_map_file(rules->file); 1330 if (error) { 1331 info = "failed to remap file permission table"; 1332 goto fail; 1333 } 1334 } 1335 } else if (rules->policy->dfa && 1336 rules->policy->start[AA_CLASS_FILE]) { 1337 aa_put_pdb(rules->file); 1338 rules->file = aa_get_pdb(rules->policy); 1339 } else { 1340 aa_put_pdb(rules->file); 1341 rules->file = aa_get_pdb(nullpdb); 1342 } 1343 error = -EPROTO; 1344 if (aa_unpack_nameX(e, AA_STRUCT, "data")) { 1345 info = "out of memory"; 1346 profile->data = kzalloc_obj(*profile->data); 1347 if (!profile->data) { 1348 error = -ENOMEM; 1349 goto fail; 1350 } 1351 params.nelem_hint = 3; 1352 params.key_len = sizeof(void *); 1353 params.key_offset = offsetof(struct aa_data, key); 1354 params.head_offset = offsetof(struct aa_data, head); 1355 params.hashfn = strhash; 1356 params.obj_cmpfn = datacmp; 1357 1358 if (rhashtable_init(profile->data, ¶ms)) { 1359 info = "failed to init key, value hash table"; 1360 goto fail; 1361 } 1362 1363 while (aa_unpack_strdup(e, &key, NULL)) { 1364 data = kzalloc_obj(*data); 1365 if (!data) { 1366 kfree_sensitive(key); 1367 error = -ENOMEM; 1368 goto fail; 1369 } 1370 1371 data->key = key; 1372 data->size = aa_unpack_blob(e, &data->data, NULL); 1373 data->data = kvmemdup(data->data, data->size, GFP_KERNEL); 1374 if (data->size && !data->data) { 1375 kfree_sensitive(data->key); 1376 kfree_sensitive(data); 1377 error = -ENOMEM; 1378 goto fail; 1379 } 1380 1381 if (rhashtable_insert_fast(profile->data, &data->head, 1382 profile->data->p)) { 1383 kvfree_sensitive(data->data, data->size); 1384 kfree_sensitive(data->key); 1385 kfree_sensitive(data); 1386 info = "failed to insert data to table"; 1387 goto fail; 1388 } 1389 } 1390 1391 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) { 1392 info = "failed to unpack end of key, value data table"; 1393 goto fail; 1394 } 1395 } 1396 1397 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) { 1398 info = "failed to unpack end of profile"; 1399 goto fail; 1400 } 1401 1402 aa_compute_profile_mediates(profile); 1403 1404 return profile; 1405 1406 fail: 1407 if (error == 0) 1408 /* default error covers most cases */ 1409 error = -EPROTO; 1410 if (*ns_name) { 1411 kfree(*ns_name); 1412 *ns_name = NULL; 1413 } 1414 if (profile) 1415 name = NULL; 1416 else if (!name) 1417 name = "unknown"; 1418 audit_iface(profile, NULL, name, info, e, error); 1419 aa_free_profile(profile); 1420 1421 return ERR_PTR(error); 1422 } 1423 1424 /** 1425 * verify_header - unpack serialized stream header 1426 * @e: serialized data read head (NOT NULL) 1427 * @required: whether the header is required or optional 1428 * @ns: Returns - namespace if one is specified else NULL (NOT NULL) 1429 * 1430 * Returns: error or 0 if header is good 1431 */ 1432 static int verify_header(struct aa_ext *e, int required, const char **ns) 1433 { 1434 int error = -EPROTONOSUPPORT; 1435 const char *name = NULL; 1436 1437 /* get the interface version */ 1438 if (!aa_unpack_u32(e, &e->version, "version")) { 1439 if (required) { 1440 audit_iface(NULL, NULL, NULL, "invalid profile format", 1441 e, error); 1442 return error; 1443 } 1444 } 1445 1446 /* Check that the interface version is currently supported. 1447 * if not specified use previous version 1448 * Mask off everything that is not kernel abi version 1449 */ 1450 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v9)) { 1451 audit_iface(NULL, NULL, NULL, "unsupported interface version", 1452 e, error); 1453 return error; 1454 } 1455 1456 /* read the namespace if present */ 1457 if (aa_unpack_str(e, &name, "namespace")) { 1458 if (*name == '\0') { 1459 audit_iface(NULL, NULL, NULL, "invalid namespace name", 1460 e, error); 1461 return error; 1462 } 1463 if (*ns && strcmp(*ns, name)) { 1464 audit_iface(NULL, NULL, NULL, "invalid ns change", e, 1465 error); 1466 } else if (!*ns) { 1467 *ns = kstrdup(name, GFP_KERNEL); 1468 if (!*ns) 1469 return -ENOMEM; 1470 } 1471 } 1472 1473 return 0; 1474 } 1475 1476 /** 1477 * verify_dfa_accept_index - verify accept indexes are in range of perms table 1478 * @dfa: the dfa to check accept indexes are in range 1479 * @table_size: the permission table size the indexes should be within 1480 */ 1481 static bool verify_dfa_accept_index(struct aa_dfa *dfa, int table_size) 1482 { 1483 int i; 1484 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) { 1485 if (ACCEPT_TABLE(dfa)[i] >= table_size) 1486 return false; 1487 } 1488 return true; 1489 } 1490 1491 static bool verify_perm(struct aa_perms *perm) 1492 { 1493 /* TODO: allow option to just force the perms into a valid state */ 1494 if (perm->allow & perm->deny) 1495 return false; 1496 if (perm->subtree & ~perm->allow) 1497 return false; 1498 if (perm->cond & (perm->allow | perm->deny)) 1499 return false; 1500 if (perm->kill & perm->allow) 1501 return false; 1502 if (perm->complain & (perm->allow | perm->deny)) 1503 return false; 1504 if (perm->prompt & (perm->allow | perm->deny)) 1505 return false; 1506 if (perm->complain & perm->prompt) 1507 return false; 1508 if (perm->hide & perm->allow) 1509 return false; 1510 1511 return true; 1512 } 1513 1514 static bool verify_perms(struct aa_policydb *pdb) 1515 { 1516 int i; 1517 int xidx, xmax = -1; 1518 1519 for (i = 0; i < pdb->size; i++) { 1520 if (!verify_perm(&pdb->perms[i])) 1521 return false; 1522 /* verify indexes into str table */ 1523 if ((pdb->perms[i].xindex & AA_X_TYPE_MASK) == AA_X_TABLE) { 1524 xidx = pdb->perms[i].xindex & AA_X_INDEX_MASK; 1525 if (xidx >= pdb->trans.size) 1526 return false; 1527 if (xmax < xidx) 1528 xmax = xidx; 1529 } 1530 if (pdb->perms[i].tag && pdb->perms[i].tag >= pdb->tags.sets.size) 1531 return false; 1532 if (pdb->perms[i].label && 1533 pdb->perms[i].label >= pdb->trans.size) 1534 return false; 1535 } 1536 /* deal with incorrectly constructed string tables */ 1537 if (xmax == -1) { 1538 aa_destroy_str_table(&pdb->trans); 1539 } else if (pdb->trans.size > xmax + 1) { 1540 if (!aa_resize_str_table(&pdb->trans, xmax + 1, GFP_KERNEL)) 1541 return false; 1542 } 1543 return true; 1544 } 1545 1546 /** 1547 * verify_profile - Do post unpack analysis to verify profile consistency 1548 * @profile: profile to verify (NOT NULL) 1549 * 1550 * Returns: 0 if passes verification else error 1551 * 1552 * This verification is post any unpack mapping or changes 1553 */ 1554 static int verify_profile(struct aa_profile *profile) 1555 { 1556 struct aa_ruleset *rules = profile->label.rules[0]; 1557 1558 if (!rules) 1559 return 0; 1560 1561 if (rules->file->dfa && !verify_dfa_accept_index(rules->file->dfa, 1562 rules->file->size)) { 1563 audit_iface(profile, NULL, NULL, 1564 "Unpack: file Invalid named transition", NULL, 1565 -EPROTO); 1566 return -EPROTO; 1567 } 1568 if (rules->policy->dfa && 1569 !verify_dfa_accept_index(rules->policy->dfa, rules->policy->size)) { 1570 audit_iface(profile, NULL, NULL, 1571 "Unpack: policy Invalid named transition", NULL, 1572 -EPROTO); 1573 return -EPROTO; 1574 } 1575 1576 if (!verify_perms(rules->file)) { 1577 audit_iface(profile, NULL, NULL, 1578 "Unpack: Invalid perm index", NULL, -EPROTO); 1579 return -EPROTO; 1580 } 1581 if (!verify_perms(rules->policy)) { 1582 audit_iface(profile, NULL, NULL, 1583 "Unpack: Invalid perm index", NULL, -EPROTO); 1584 return -EPROTO; 1585 } 1586 if (!verify_perms(profile->attach.xmatch)) { 1587 audit_iface(profile, NULL, NULL, 1588 "Unpack: Invalid perm index", NULL, -EPROTO); 1589 return -EPROTO; 1590 } 1591 1592 return 0; 1593 } 1594 1595 void aa_load_ent_free(struct aa_load_ent *ent) 1596 { 1597 if (ent) { 1598 aa_put_profile(ent->rename); 1599 aa_put_profile(ent->old); 1600 aa_put_profile(ent->new); 1601 kfree(ent->ns_name); 1602 kfree_sensitive(ent); 1603 } 1604 } 1605 1606 struct aa_load_ent *aa_load_ent_alloc(void) 1607 { 1608 struct aa_load_ent *ent = kzalloc_obj(*ent); 1609 if (ent) 1610 INIT_LIST_HEAD(&ent->list); 1611 return ent; 1612 } 1613 1614 static int compress_zstd(const char *src, size_t slen, char **dst, size_t *dlen) 1615 { 1616 #ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY 1617 const zstd_parameters params = 1618 zstd_get_params(aa_g_rawdata_compression_level, slen); 1619 const size_t wksp_len = zstd_cctx_workspace_bound(¶ms.cParams); 1620 void *wksp = NULL; 1621 zstd_cctx *ctx = NULL; 1622 size_t out_len = zstd_compress_bound(slen); 1623 void *out = NULL; 1624 int ret = 0; 1625 1626 out = kvzalloc(out_len, GFP_KERNEL); 1627 if (!out) { 1628 ret = -ENOMEM; 1629 goto cleanup; 1630 } 1631 1632 wksp = kvzalloc(wksp_len, GFP_KERNEL); 1633 if (!wksp) { 1634 ret = -ENOMEM; 1635 goto cleanup; 1636 } 1637 1638 ctx = zstd_init_cctx(wksp, wksp_len); 1639 if (!ctx) { 1640 ret = -EINVAL; 1641 goto cleanup; 1642 } 1643 1644 out_len = zstd_compress_cctx(ctx, out, out_len, src, slen, ¶ms); 1645 if (zstd_is_error(out_len) || out_len >= slen) { 1646 ret = -EINVAL; 1647 goto cleanup; 1648 } 1649 1650 if (is_vmalloc_addr(out)) { 1651 *dst = kvzalloc(out_len, GFP_KERNEL); 1652 if (*dst) { 1653 memcpy(*dst, out, out_len); 1654 kvfree(out); 1655 out = NULL; 1656 } 1657 } else { 1658 /* 1659 * If the staging buffer was kmalloc'd, then using krealloc is 1660 * probably going to be faster. The destination buffer will 1661 * always be smaller, so it's just shrunk, avoiding a memcpy 1662 */ 1663 *dst = krealloc(out, out_len, GFP_KERNEL); 1664 } 1665 1666 if (!*dst) { 1667 ret = -ENOMEM; 1668 goto cleanup; 1669 } 1670 1671 *dlen = out_len; 1672 1673 cleanup: 1674 if (ret) { 1675 kvfree(out); 1676 *dst = NULL; 1677 } 1678 1679 kvfree(wksp); 1680 return ret; 1681 #else 1682 *dlen = slen; 1683 return 0; 1684 #endif 1685 } 1686 1687 static int compress_loaddata(struct aa_loaddata *data) 1688 { 1689 AA_BUG(data->compressed_size > 0); 1690 1691 /* 1692 * Shortcut the no compression case, else we increase the amount of 1693 * storage required by a small amount 1694 */ 1695 if (aa_g_rawdata_compression_level != 0) { 1696 void *udata = data->data; 1697 int error = compress_zstd(udata, data->size, &data->data, 1698 &data->compressed_size); 1699 if (error) { 1700 data->compressed_size = data->size; 1701 return error; 1702 } 1703 if (udata != data->data) 1704 kvfree(udata); 1705 } else 1706 data->compressed_size = data->size; 1707 1708 return 0; 1709 } 1710 1711 /** 1712 * aa_unpack - unpack packed binary profile(s) data loaded from user space 1713 * @udata: user data copied to kmem (NOT NULL) 1714 * @lh: list to place unpacked profiles in a aa_repl_ws 1715 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL) 1716 * 1717 * Unpack user data and return refcounted allocated profile(s) stored in 1718 * @lh in order of discovery, with the list chain stored in base.list 1719 * or error 1720 * 1721 * Returns: profile(s) on @lh else error pointer if fails to unpack 1722 */ 1723 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh, 1724 const char **ns) 1725 { 1726 struct aa_load_ent *tmp, *ent; 1727 struct aa_profile *profile = NULL; 1728 char *ns_name = NULL; 1729 int error; 1730 struct aa_ext e = { 1731 .start = udata->data, 1732 .end = udata->data + udata->size, 1733 .pos = udata->data, 1734 }; 1735 1736 *ns = NULL; 1737 while (e.pos < e.end) { 1738 void *start; 1739 error = verify_header(&e, e.pos == e.start, ns); 1740 if (error) 1741 goto fail; 1742 1743 start = e.pos; 1744 profile = unpack_profile(&e, &ns_name); 1745 if (IS_ERR(profile)) { 1746 error = PTR_ERR(profile); 1747 goto fail; 1748 } 1749 1750 error = verify_profile(profile); 1751 if (error) 1752 goto fail_profile; 1753 1754 if (aa_g_hash_policy) 1755 error = aa_calc_profile_hash(profile, e.version, start, 1756 e.pos - start); 1757 if (error) 1758 goto fail_profile; 1759 1760 ent = aa_load_ent_alloc(); 1761 if (!ent) { 1762 error = -ENOMEM; 1763 goto fail_profile; 1764 } 1765 1766 ent->new = profile; 1767 ent->ns_name = ns_name; 1768 ns_name = NULL; 1769 list_add_tail(&ent->list, lh); 1770 } 1771 udata->abi = e.version & K_ABI_MASK; 1772 if (aa_g_hash_policy) { 1773 udata->hash = aa_calc_hash(udata->data, udata->size); 1774 if (IS_ERR(udata->hash)) { 1775 error = PTR_ERR(udata->hash); 1776 udata->hash = NULL; 1777 goto fail; 1778 } 1779 } 1780 1781 if (aa_g_export_binary) { 1782 error = compress_loaddata(udata); 1783 if (error) 1784 goto fail; 1785 } 1786 return 0; 1787 1788 fail_profile: 1789 kfree(ns_name); 1790 aa_put_profile(profile); 1791 1792 fail: 1793 list_for_each_entry_safe(ent, tmp, lh, list) { 1794 list_del_init(&ent->list); 1795 aa_load_ent_free(ent); 1796 } 1797 1798 return error; 1799 } 1800