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 */
audit_cb(struct audit_buffer * ab,void * va)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 */
audit_iface(struct aa_profile * new,const char * ns_name,const char * name,const char * info,struct aa_ext * e,int error)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
__aa_loaddata_update(struct aa_loaddata * data,long revision)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
aa_rawdata_eq(struct aa_loaddata * l,struct aa_loaddata * r)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 */
do_loaddata_free(struct work_struct * work)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
aa_loaddata_kref(struct kref * kref)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
aa_loaddata_alloc(size_t size)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 */
aa_inbounds(struct aa_ext * e,size_t size)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 */
aa_unpack_u16_chunk(struct aa_ext * e,char ** chunk)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 */
aa_unpack_X(struct aa_ext * e,enum aa_code code)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 */
aa_unpack_nameX(struct aa_ext * e,enum aa_code code,const char * name)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
unpack_u8(struct aa_ext * e,u8 * data,const char * name)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
aa_unpack_u32(struct aa_ext * e,u32 * data,const char * name)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
aa_unpack_u64(struct aa_ext * e,u64 * data,const char * name)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
aa_unpack_cap_low(struct aa_ext * e,kernel_cap_t * data,const char * name)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
aa_unpack_cap_high(struct aa_ext * e,kernel_cap_t * data,const char * name)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
aa_unpack_array(struct aa_ext * e,const char * name,u16 * size)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
aa_unpack_blob(struct aa_ext * e,char ** blob,const char * name)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
aa_unpack_str(struct aa_ext * e,const char ** string,const char * name)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
aa_unpack_strdup(struct aa_ext * e,char ** string,const char * name)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 */
unpack_dfa(struct aa_ext * e,int flags)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
process_strs_entry(char * str,int size,bool multi)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 */
unpack_strs_table(struct aa_ext * e,const char * name,bool multi,struct aa_str_table * strs)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
unpack_xattrs(struct aa_ext * e,struct aa_profile * profile)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
unpack_secmark(struct aa_ext * e,struct aa_ruleset * rules)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
unpack_rlimits(struct aa_ext * e,struct aa_ruleset * rules)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
verify_tags(struct aa_tags_struct * tags,const char ** info)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
unpack_tagsets(struct aa_ext * e,struct aa_tags_struct * tags)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
unpack_tag_header_ent(struct aa_ext * e,struct aa_tags_header * h)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
unpack_tag_headers(struct aa_ext * e,struct aa_tags_struct * tags)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
unpack_tags(struct aa_ext * e,struct aa_tags_struct * tags,const char ** info)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
unpack_perm(struct aa_ext * e,u32 version,struct aa_perms * perm)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
unpack_perms_table(struct aa_ext * e,struct aa_perms ** perms)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
unpack_pdb(struct aa_ext * e,struct aa_policydb ** policy,bool required_dfa,bool required_trans,const char ** info)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
strhash(const void * data,u32 len,u32 seed)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
datacmp(struct rhashtable_compare_arg * arg,const void * obj)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 */
unpack_profile(struct aa_ext * e,char ** ns_name)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 */
verify_header(struct aa_ext * e,int required,const char ** ns)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 */
verify_dfa_accept_index(struct aa_dfa * dfa,int table_size)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
verify_perm(struct aa_perms * perm)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
verify_perms(struct aa_policydb * pdb)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 */
verify_profile(struct aa_profile * profile)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
aa_load_ent_free(struct aa_load_ent * ent)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
aa_load_ent_alloc(void)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
compress_zstd(const char * src,size_t slen,char ** dst,size_t * dlen)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
compress_loaddata(struct aa_loaddata * data)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 */
aa_unpack(struct aa_loaddata * udata,struct list_head * lh,const char ** ns)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