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TOMOYO Linux Cross Reference
Linux/security/apparmor/policy_unpack.c

Version: ~ [ linux-5.12 ] ~ [ linux-5.11.16 ] ~ [ linux-5.10.32 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.114 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.188 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.231 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.267 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.267 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * AppArmor security module
  3  *
  4  * This file contains AppArmor functions for unpacking policy loaded from
  5  * userspace.
  6  *
  7  * Copyright (C) 1998-2008 Novell/SUSE
  8  * Copyright 2009-2010 Canonical Ltd.
  9  *
 10  * This program is free software; you can redistribute it and/or
 11  * modify it under the terms of the GNU General Public License as
 12  * published by the Free Software Foundation, version 2 of the
 13  * License.
 14  *
 15  * AppArmor uses a serialized binary format for loading policy. To find
 16  * policy format documentation see Documentation/admin-guide/LSM/apparmor.rst
 17  * All policy is validated before it is used.
 18  */
 19 
 20 #include <asm/unaligned.h>
 21 #include <linux/ctype.h>
 22 #include <linux/errno.h>
 23 
 24 #include "include/apparmor.h"
 25 #include "include/audit.h"
 26 #include "include/context.h"
 27 #include "include/crypto.h"
 28 #include "include/match.h"
 29 #include "include/path.h"
 30 #include "include/policy.h"
 31 #include "include/policy_unpack.h"
 32 
 33 #define K_ABI_MASK 0x3ff
 34 #define FORCE_COMPLAIN_FLAG 0x800
 35 #define VERSION_LT(X, Y) (((X) & K_ABI_MASK) < ((Y) & K_ABI_MASK))
 36 #define VERSION_GT(X, Y) (((X) & K_ABI_MASK) > ((Y) & K_ABI_MASK))
 37 
 38 #define v5      5       /* base version */
 39 #define v6      6       /* per entry policydb mediation check */
 40 #define v7      7       /* full network masking */
 41 
 42 /*
 43  * The AppArmor interface treats data as a type byte followed by the
 44  * actual data.  The interface has the notion of a a named entry
 45  * which has a name (AA_NAME typecode followed by name string) followed by
 46  * the entries typecode and data.  Named types allow for optional
 47  * elements and extensions to be added and tested for without breaking
 48  * backwards compatibility.
 49  */
 50 
 51 enum aa_code {
 52         AA_U8,
 53         AA_U16,
 54         AA_U32,
 55         AA_U64,
 56         AA_NAME,                /* same as string except it is items name */
 57         AA_STRING,
 58         AA_BLOB,
 59         AA_STRUCT,
 60         AA_STRUCTEND,
 61         AA_LIST,
 62         AA_LISTEND,
 63         AA_ARRAY,
 64         AA_ARRAYEND,
 65 };
 66 
 67 /*
 68  * aa_ext is the read of the buffer containing the serialized profile.  The
 69  * data is copied into a kernel buffer in apparmorfs and then handed off to
 70  * the unpack routines.
 71  */
 72 struct aa_ext {
 73         void *start;
 74         void *end;
 75         void *pos;              /* pointer to current position in the buffer */
 76         u32 version;
 77 };
 78 
 79 /* audit callback for unpack fields */
 80 static void audit_cb(struct audit_buffer *ab, void *va)
 81 {
 82         struct common_audit_data *sa = va;
 83 
 84         if (aad(sa)->iface.ns) {
 85                 audit_log_format(ab, " ns=");
 86                 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
 87         }
 88         if (aad(sa)->iface.name) {
 89                 audit_log_format(ab, " name=");
 90                 audit_log_untrustedstring(ab, aad(sa)->iface.name);
 91         }
 92         if (aad(sa)->iface.pos)
 93                 audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
 94 }
 95 
 96 /**
 97  * audit_iface - do audit message for policy unpacking/load/replace/remove
 98  * @new: profile if it has been allocated (MAYBE NULL)
 99  * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
100  * @name: name of the profile being manipulated (MAYBE NULL)
101  * @info: any extra info about the failure (MAYBE NULL)
102  * @e: buffer position info
103  * @error: error code
104  *
105  * Returns: %0 or error
106  */
107 static int audit_iface(struct aa_profile *new, const char *ns_name,
108                        const char *name, const char *info, struct aa_ext *e,
109                        int error)
110 {
111         struct aa_profile *profile = labels_profile(aa_current_raw_label());
112         DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, NULL);
113         if (e)
114                 aad(&sa)->iface.pos = e->pos - e->start;
115         aad(&sa)->iface.ns = ns_name;
116         if (new)
117                 aad(&sa)->iface.name = new->base.hname;
118         else
119                 aad(&sa)->iface.name = name;
120         aad(&sa)->info = info;
121         aad(&sa)->error = error;
122 
123         return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
124 }
125 
126 void __aa_loaddata_update(struct aa_loaddata *data, long revision)
127 {
128         AA_BUG(!data);
129         AA_BUG(!data->ns);
130         AA_BUG(!data->dents[AAFS_LOADDATA_REVISION]);
131         AA_BUG(!mutex_is_locked(&data->ns->lock));
132         AA_BUG(data->revision > revision);
133 
134         data->revision = revision;
135         d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
136                 current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
137         d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
138                 current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
139 }
140 
141 bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
142 {
143         if (l->size != r->size)
144                 return false;
145         if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
146                 return false;
147         return memcmp(l->data, r->data, r->size) == 0;
148 }
149 
150 /*
151  * need to take the ns mutex lock which is NOT safe most places that
152  * put_loaddata is called, so we have to delay freeing it
153  */
154 static void do_loaddata_free(struct work_struct *work)
155 {
156         struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
157         struct aa_ns *ns = aa_get_ns(d->ns);
158 
159         if (ns) {
160                 mutex_lock(&ns->lock);
161                 __aa_fs_remove_rawdata(d);
162                 mutex_unlock(&ns->lock);
163                 aa_put_ns(ns);
164         }
165 
166         kzfree(d->hash);
167         kfree(d->name);
168         kvfree(d);
169 }
170 
171 void aa_loaddata_kref(struct kref *kref)
172 {
173         struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
174 
175         if (d) {
176                 INIT_WORK(&d->work, do_loaddata_free);
177                 schedule_work(&d->work);
178         }
179 }
180 
181 struct aa_loaddata *aa_loaddata_alloc(size_t size)
182 {
183         struct aa_loaddata *d = kvzalloc(sizeof(*d) + size, GFP_KERNEL);
184 
185         if (d == NULL)
186                 return ERR_PTR(-ENOMEM);
187         kref_init(&d->count);
188         INIT_LIST_HEAD(&d->list);
189 
190         return d;
191 }
192 
193 /* test if read will be in packed data bounds */
194 static bool inbounds(struct aa_ext *e, size_t size)
195 {
196         return (size <= e->end - e->pos);
197 }
198 
199 /**
200  * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
201  * @e: serialized data read head (NOT NULL)
202  * @chunk: start address for chunk of data (NOT NULL)
203  *
204  * Returns: the size of chunk found with the read head at the end of the chunk.
205  */
206 static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
207 {
208         size_t size = 0;
209 
210         if (!inbounds(e, sizeof(u16)))
211                 return 0;
212         size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
213         e->pos += sizeof(__le16);
214         if (!inbounds(e, size))
215                 return 0;
216         *chunk = e->pos;
217         e->pos += size;
218         return size;
219 }
220 
221 /* unpack control byte */
222 static bool unpack_X(struct aa_ext *e, enum aa_code code)
223 {
224         if (!inbounds(e, 1))
225                 return 0;
226         if (*(u8 *) e->pos != code)
227                 return 0;
228         e->pos++;
229         return 1;
230 }
231 
232 /**
233  * unpack_nameX - check is the next element is of type X with a name of @name
234  * @e: serialized data extent information  (NOT NULL)
235  * @code: type code
236  * @name: name to match to the serialized element.  (MAYBE NULL)
237  *
238  * check that the next serialized data element is of type X and has a tag
239  * name @name.  If @name is specified then there must be a matching
240  * name element in the stream.  If @name is NULL any name element will be
241  * skipped and only the typecode will be tested.
242  *
243  * Returns 1 on success (both type code and name tests match) and the read
244  * head is advanced past the headers
245  *
246  * Returns: 0 if either match fails, the read head does not move
247  */
248 static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
249 {
250         /*
251          * May need to reset pos if name or type doesn't match
252          */
253         void *pos = e->pos;
254         /*
255          * Check for presence of a tagname, and if present name size
256          * AA_NAME tag value is a u16.
257          */
258         if (unpack_X(e, AA_NAME)) {
259                 char *tag = NULL;
260                 size_t size = unpack_u16_chunk(e, &tag);
261                 /* if a name is specified it must match. otherwise skip tag */
262                 if (name && (!size || strcmp(name, tag)))
263                         goto fail;
264         } else if (name) {
265                 /* if a name is specified and there is no name tag fail */
266                 goto fail;
267         }
268 
269         /* now check if type code matches */
270         if (unpack_X(e, code))
271                 return 1;
272 
273 fail:
274         e->pos = pos;
275         return 0;
276 }
277 
278 static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
279 {
280         if (unpack_nameX(e, AA_U32, name)) {
281                 if (!inbounds(e, sizeof(u32)))
282                         return 0;
283                 if (data)
284                         *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
285                 e->pos += sizeof(u32);
286                 return 1;
287         }
288         return 0;
289 }
290 
291 static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
292 {
293         if (unpack_nameX(e, AA_U64, name)) {
294                 if (!inbounds(e, sizeof(u64)))
295                         return 0;
296                 if (data)
297                         *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
298                 e->pos += sizeof(u64);
299                 return 1;
300         }
301         return 0;
302 }
303 
304 static size_t unpack_array(struct aa_ext *e, const char *name)
305 {
306         if (unpack_nameX(e, AA_ARRAY, name)) {
307                 int size;
308                 if (!inbounds(e, sizeof(u16)))
309                         return 0;
310                 size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
311                 e->pos += sizeof(u16);
312                 return size;
313         }
314         return 0;
315 }
316 
317 static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
318 {
319         if (unpack_nameX(e, AA_BLOB, name)) {
320                 u32 size;
321                 if (!inbounds(e, sizeof(u32)))
322                         return 0;
323                 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
324                 e->pos += sizeof(u32);
325                 if (inbounds(e, (size_t) size)) {
326                         *blob = e->pos;
327                         e->pos += size;
328                         return size;
329                 }
330         }
331         return 0;
332 }
333 
334 static int unpack_str(struct aa_ext *e, const char **string, const char *name)
335 {
336         char *src_str;
337         size_t size = 0;
338         void *pos = e->pos;
339         *string = NULL;
340         if (unpack_nameX(e, AA_STRING, name)) {
341                 size = unpack_u16_chunk(e, &src_str);
342                 if (size) {
343                         /* strings are null terminated, length is size - 1 */
344                         if (src_str[size - 1] != 0)
345                                 goto fail;
346                         *string = src_str;
347                 }
348         }
349         return size;
350 
351 fail:
352         e->pos = pos;
353         return 0;
354 }
355 
356 static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
357 {
358         const char *tmp;
359         void *pos = e->pos;
360         int res = unpack_str(e, &tmp, name);
361         *string = NULL;
362 
363         if (!res)
364                 return 0;
365 
366         *string = kmemdup(tmp, res, GFP_KERNEL);
367         if (!*string) {
368                 e->pos = pos;
369                 return 0;
370         }
371 
372         return res;
373 }
374 
375 #define DFA_VALID_PERM_MASK             0xffffffff
376 #define DFA_VALID_PERM2_MASK            0xffffffff
377 
378 /**
379  * verify_accept - verify the accept tables of a dfa
380  * @dfa: dfa to verify accept tables of (NOT NULL)
381  * @flags: flags governing dfa
382  *
383  * Returns: 1 if valid accept tables else 0 if error
384  */
385 static bool verify_accept(struct aa_dfa *dfa, int flags)
386 {
387         int i;
388 
389         /* verify accept permissions */
390         for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
391                 int mode = ACCEPT_TABLE(dfa)[i];
392 
393                 if (mode & ~DFA_VALID_PERM_MASK)
394                         return 0;
395 
396                 if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK)
397                         return 0;
398         }
399         return 1;
400 }
401 
402 /**
403  * unpack_dfa - unpack a file rule dfa
404  * @e: serialized data extent information (NOT NULL)
405  *
406  * returns dfa or ERR_PTR or NULL if no dfa
407  */
408 static struct aa_dfa *unpack_dfa(struct aa_ext *e)
409 {
410         char *blob = NULL;
411         size_t size;
412         struct aa_dfa *dfa = NULL;
413 
414         size = unpack_blob(e, &blob, "aadfa");
415         if (size) {
416                 /*
417                  * The dfa is aligned with in the blob to 8 bytes
418                  * from the beginning of the stream.
419                  * alignment adjust needed by dfa unpack
420                  */
421                 size_t sz = blob - (char *) e->start -
422                         ((e->pos - e->start) & 7);
423                 size_t pad = ALIGN(sz, 8) - sz;
424                 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
425                         TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES;
426                 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
427 
428                 if (IS_ERR(dfa))
429                         return dfa;
430 
431                 if (!verify_accept(dfa, flags))
432                         goto fail;
433         }
434 
435         return dfa;
436 
437 fail:
438         aa_put_dfa(dfa);
439         return ERR_PTR(-EPROTO);
440 }
441 
442 /**
443  * unpack_trans_table - unpack a profile transition table
444  * @e: serialized data extent information  (NOT NULL)
445  * @profile: profile to add the accept table to (NOT NULL)
446  *
447  * Returns: 1 if table successfully unpacked
448  */
449 static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
450 {
451         void *pos = e->pos;
452 
453         /* exec table is optional */
454         if (unpack_nameX(e, AA_STRUCT, "xtable")) {
455                 int i, size;
456 
457                 size = unpack_array(e, NULL);
458                 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
459                 if (size > 16 - 4)
460                         goto fail;
461                 profile->file.trans.table = kzalloc(sizeof(char *) * size,
462                                                     GFP_KERNEL);
463                 if (!profile->file.trans.table)
464                         goto fail;
465 
466                 profile->file.trans.size = size;
467                 for (i = 0; i < size; i++) {
468                         char *str;
469                         int c, j, pos, size2 = unpack_strdup(e, &str, NULL);
470                         /* unpack_strdup verifies that the last character is
471                          * null termination byte.
472                          */
473                         if (!size2)
474                                 goto fail;
475                         profile->file.trans.table[i] = str;
476                         /* verify that name doesn't start with space */
477                         if (isspace(*str))
478                                 goto fail;
479 
480                         /* count internal #  of internal \0 */
481                         for (c = j = 0; j < size2 - 1; j++) {
482                                 if (!str[j]) {
483                                         pos = j;
484                                         c++;
485                                 }
486                         }
487                         if (*str == ':') {
488                                 /* first character after : must be valid */
489                                 if (!str[1])
490                                         goto fail;
491                                 /* beginning with : requires an embedded \0,
492                                  * verify that exactly 1 internal \0 exists
493                                  * trailing \0 already verified by unpack_strdup
494                                  *
495                                  * convert \0 back to : for label_parse
496                                  */
497                                 if (c == 1)
498                                         str[pos] = ':';
499                                 else if (c > 1)
500                                         goto fail;
501                         } else if (c)
502                                 /* fail - all other cases with embedded \0 */
503                                 goto fail;
504                 }
505                 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
506                         goto fail;
507                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
508                         goto fail;
509         }
510         return 1;
511 
512 fail:
513         aa_free_domain_entries(&profile->file.trans);
514         e->pos = pos;
515         return 0;
516 }
517 
518 static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
519 {
520         void *pos = e->pos;
521 
522         /* rlimits are optional */
523         if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
524                 int i, size;
525                 u32 tmp = 0;
526                 if (!unpack_u32(e, &tmp, NULL))
527                         goto fail;
528                 profile->rlimits.mask = tmp;
529 
530                 size = unpack_array(e, NULL);
531                 if (size > RLIM_NLIMITS)
532                         goto fail;
533                 for (i = 0; i < size; i++) {
534                         u64 tmp2 = 0;
535                         int a = aa_map_resource(i);
536                         if (!unpack_u64(e, &tmp2, NULL))
537                                 goto fail;
538                         profile->rlimits.limits[a].rlim_max = tmp2;
539                 }
540                 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
541                         goto fail;
542                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
543                         goto fail;
544         }
545         return 1;
546 
547 fail:
548         e->pos = pos;
549         return 0;
550 }
551 
552 static void *kvmemdup(const void *src, size_t len)
553 {
554         void *p = kvmalloc(len, GFP_KERNEL);
555 
556         if (p)
557                 memcpy(p, src, len);
558         return p;
559 }
560 
561 static u32 strhash(const void *data, u32 len, u32 seed)
562 {
563         const char * const *key = data;
564 
565         return jhash(*key, strlen(*key), seed);
566 }
567 
568 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
569 {
570         const struct aa_data *data = obj;
571         const char * const *key = arg->key;
572 
573         return strcmp(data->key, *key);
574 }
575 
576 /**
577  * unpack_profile - unpack a serialized profile
578  * @e: serialized data extent information (NOT NULL)
579  *
580  * NOTE: unpack profile sets audit struct if there is a failure
581  */
582 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
583 {
584         struct aa_profile *profile = NULL;
585         const char *tmpname, *tmpns = NULL, *name = NULL;
586         size_t ns_len;
587         struct rhashtable_params params = { 0 };
588         char *key = NULL;
589         struct aa_data *data;
590         int i, error = -EPROTO;
591         kernel_cap_t tmpcap;
592         u32 tmp;
593 
594         *ns_name = NULL;
595 
596         /* check that we have the right struct being passed */
597         if (!unpack_nameX(e, AA_STRUCT, "profile"))
598                 goto fail;
599         if (!unpack_str(e, &name, NULL))
600                 goto fail;
601         if (*name == '\0')
602                 goto fail;
603 
604         tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
605         if (tmpns) {
606                 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
607                 if (!*ns_name)
608                         goto fail;
609                 name = tmpname;
610         }
611 
612         profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
613         if (!profile)
614                 return ERR_PTR(-ENOMEM);
615 
616         /* profile renaming is optional */
617         (void) unpack_str(e, &profile->rename, "rename");
618 
619         /* attachment string is optional */
620         (void) unpack_str(e, &profile->attach, "attach");
621 
622         /* xmatch is optional and may be NULL */
623         profile->xmatch = unpack_dfa(e);
624         if (IS_ERR(profile->xmatch)) {
625                 error = PTR_ERR(profile->xmatch);
626                 profile->xmatch = NULL;
627                 goto fail;
628         }
629         /* xmatch_len is not optional if xmatch is set */
630         if (profile->xmatch) {
631                 if (!unpack_u32(e, &tmp, NULL))
632                         goto fail;
633                 profile->xmatch_len = tmp;
634         }
635 
636         /* disconnected attachment string is optional */
637         (void) unpack_str(e, &profile->disconnected, "disconnected");
638 
639         /* per profile debug flags (complain, audit) */
640         if (!unpack_nameX(e, AA_STRUCT, "flags"))
641                 goto fail;
642         if (!unpack_u32(e, &tmp, NULL))
643                 goto fail;
644         if (tmp & PACKED_FLAG_HAT)
645                 profile->label.flags |= FLAG_HAT;
646         if (!unpack_u32(e, &tmp, NULL))
647                 goto fail;
648         if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG))
649                 profile->mode = APPARMOR_COMPLAIN;
650         else if (tmp == PACKED_MODE_KILL)
651                 profile->mode = APPARMOR_KILL;
652         else if (tmp == PACKED_MODE_UNCONFINED)
653                 profile->mode = APPARMOR_UNCONFINED;
654         if (!unpack_u32(e, &tmp, NULL))
655                 goto fail;
656         if (tmp)
657                 profile->audit = AUDIT_ALL;
658 
659         if (!unpack_nameX(e, AA_STRUCTEND, NULL))
660                 goto fail;
661 
662         /* path_flags is optional */
663         if (unpack_u32(e, &profile->path_flags, "path_flags"))
664                 profile->path_flags |= profile->label.flags &
665                         PATH_MEDIATE_DELETED;
666         else
667                 /* set a default value if path_flags field is not present */
668                 profile->path_flags = PATH_MEDIATE_DELETED;
669 
670         if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
671                 goto fail;
672         if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
673                 goto fail;
674         if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
675                 goto fail;
676         if (!unpack_u32(e, &tmpcap.cap[0], NULL))
677                 goto fail;
678 
679         if (unpack_nameX(e, AA_STRUCT, "caps64")) {
680                 /* optional upper half of 64 bit caps */
681                 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
682                         goto fail;
683                 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
684                         goto fail;
685                 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
686                         goto fail;
687                 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
688                         goto fail;
689                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
690                         goto fail;
691         }
692 
693         if (unpack_nameX(e, AA_STRUCT, "capsx")) {
694                 /* optional extended caps mediation mask */
695                 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
696                         goto fail;
697                 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
698                         goto fail;
699                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
700                         goto fail;
701         }
702 
703         if (!unpack_rlimits(e, profile))
704                 goto fail;
705 
706         if (unpack_nameX(e, AA_STRUCT, "policydb")) {
707                 /* generic policy dfa - optional and may be NULL */
708                 profile->policy.dfa = unpack_dfa(e);
709                 if (IS_ERR(profile->policy.dfa)) {
710                         error = PTR_ERR(profile->policy.dfa);
711                         profile->policy.dfa = NULL;
712                         goto fail;
713                 } else if (!profile->policy.dfa) {
714                         error = -EPROTO;
715                         goto fail;
716                 }
717                 if (!unpack_u32(e, &profile->policy.start[0], "start"))
718                         /* default start state */
719                         profile->policy.start[0] = DFA_START;
720                 /* setup class index */
721                 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
722                         profile->policy.start[i] =
723                                 aa_dfa_next(profile->policy.dfa,
724                                             profile->policy.start[0],
725                                             i);
726                 }
727                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
728                         goto fail;
729         } else
730                 profile->policy.dfa = aa_get_dfa(nulldfa);
731 
732         /* get file rules */
733         profile->file.dfa = unpack_dfa(e);
734         if (IS_ERR(profile->file.dfa)) {
735                 error = PTR_ERR(profile->file.dfa);
736                 profile->file.dfa = NULL;
737                 goto fail;
738         } else if (profile->file.dfa) {
739                 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
740                         /* default start state */
741                         profile->file.start = DFA_START;
742         } else if (profile->policy.dfa &&
743                    profile->policy.start[AA_CLASS_FILE]) {
744                 profile->file.dfa = aa_get_dfa(profile->policy.dfa);
745                 profile->file.start = profile->policy.start[AA_CLASS_FILE];
746         } else
747                 profile->file.dfa = aa_get_dfa(nulldfa);
748 
749         if (!unpack_trans_table(e, profile))
750                 goto fail;
751 
752         if (unpack_nameX(e, AA_STRUCT, "data")) {
753                 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
754                 if (!profile->data)
755                         goto fail;
756 
757                 params.nelem_hint = 3;
758                 params.key_len = sizeof(void *);
759                 params.key_offset = offsetof(struct aa_data, key);
760                 params.head_offset = offsetof(struct aa_data, head);
761                 params.hashfn = strhash;
762                 params.obj_cmpfn = datacmp;
763 
764                 if (rhashtable_init(profile->data, &params))
765                         goto fail;
766 
767                 while (unpack_strdup(e, &key, NULL)) {
768                         data = kzalloc(sizeof(*data), GFP_KERNEL);
769                         if (!data) {
770                                 kzfree(key);
771                                 goto fail;
772                         }
773 
774                         data->key = key;
775                         data->size = unpack_blob(e, &data->data, NULL);
776                         data->data = kvmemdup(data->data, data->size);
777                         if (data->size && !data->data) {
778                                 kzfree(data->key);
779                                 kzfree(data);
780                                 goto fail;
781                         }
782 
783                         rhashtable_insert_fast(profile->data, &data->head,
784                                                profile->data->p);
785                 }
786 
787                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
788                         goto fail;
789         }
790 
791         if (!unpack_nameX(e, AA_STRUCTEND, NULL))
792                 goto fail;
793 
794         return profile;
795 
796 fail:
797         if (profile)
798                 name = NULL;
799         else if (!name)
800                 name = "unknown";
801         audit_iface(profile, NULL, name, "failed to unpack profile", e,
802                     error);
803         aa_free_profile(profile);
804 
805         return ERR_PTR(error);
806 }
807 
808 /**
809  * verify_head - unpack serialized stream header
810  * @e: serialized data read head (NOT NULL)
811  * @required: whether the header is required or optional
812  * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
813  *
814  * Returns: error or 0 if header is good
815  */
816 static int verify_header(struct aa_ext *e, int required, const char **ns)
817 {
818         int error = -EPROTONOSUPPORT;
819         const char *name = NULL;
820         *ns = NULL;
821 
822         /* get the interface version */
823         if (!unpack_u32(e, &e->version, "version")) {
824                 if (required) {
825                         audit_iface(NULL, NULL, NULL, "invalid profile format",
826                                     e, error);
827                         return error;
828                 }
829         }
830 
831         /* Check that the interface version is currently supported.
832          * if not specified use previous version
833          * Mask off everything that is not kernel abi version
834          */
835         if (VERSION_LT(e->version, v5) && VERSION_GT(e->version, v7)) {
836                 audit_iface(NULL, NULL, NULL, "unsupported interface version",
837                             e, error);
838                 return error;
839         }
840 
841         /* read the namespace if present */
842         if (unpack_str(e, &name, "namespace")) {
843                 if (*name == '\0') {
844                         audit_iface(NULL, NULL, NULL, "invalid namespace name",
845                                     e, error);
846                         return error;
847                 }
848                 if (*ns && strcmp(*ns, name))
849                         audit_iface(NULL, NULL, NULL, "invalid ns change", e,
850                                     error);
851                 else if (!*ns)
852                         *ns = name;
853         }
854 
855         return 0;
856 }
857 
858 static bool verify_xindex(int xindex, int table_size)
859 {
860         int index, xtype;
861         xtype = xindex & AA_X_TYPE_MASK;
862         index = xindex & AA_X_INDEX_MASK;
863         if (xtype == AA_X_TABLE && index >= table_size)
864                 return 0;
865         return 1;
866 }
867 
868 /* verify dfa xindexes are in range of transition tables */
869 static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
870 {
871         int i;
872         for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
873                 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
874                         return 0;
875                 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
876                         return 0;
877         }
878         return 1;
879 }
880 
881 /**
882  * verify_profile - Do post unpack analysis to verify profile consistency
883  * @profile: profile to verify (NOT NULL)
884  *
885  * Returns: 0 if passes verification else error
886  */
887 static int verify_profile(struct aa_profile *profile)
888 {
889         if (profile->file.dfa &&
890             !verify_dfa_xindex(profile->file.dfa,
891                                profile->file.trans.size)) {
892                 audit_iface(profile, NULL, NULL, "Invalid named transition",
893                             NULL, -EPROTO);
894                 return -EPROTO;
895         }
896 
897         return 0;
898 }
899 
900 void aa_load_ent_free(struct aa_load_ent *ent)
901 {
902         if (ent) {
903                 aa_put_profile(ent->rename);
904                 aa_put_profile(ent->old);
905                 aa_put_profile(ent->new);
906                 kfree(ent->ns_name);
907                 kzfree(ent);
908         }
909 }
910 
911 struct aa_load_ent *aa_load_ent_alloc(void)
912 {
913         struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
914         if (ent)
915                 INIT_LIST_HEAD(&ent->list);
916         return ent;
917 }
918 
919 /**
920  * aa_unpack - unpack packed binary profile(s) data loaded from user space
921  * @udata: user data copied to kmem  (NOT NULL)
922  * @lh: list to place unpacked profiles in a aa_repl_ws
923  * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
924  *
925  * Unpack user data and return refcounted allocated profile(s) stored in
926  * @lh in order of discovery, with the list chain stored in base.list
927  * or error
928  *
929  * Returns: profile(s) on @lh else error pointer if fails to unpack
930  */
931 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
932               const char **ns)
933 {
934         struct aa_load_ent *tmp, *ent;
935         struct aa_profile *profile = NULL;
936         int error;
937         struct aa_ext e = {
938                 .start = udata->data,
939                 .end = udata->data + udata->size,
940                 .pos = udata->data,
941         };
942 
943         *ns = NULL;
944         while (e.pos < e.end) {
945                 char *ns_name = NULL;
946                 void *start;
947                 error = verify_header(&e, e.pos == e.start, ns);
948                 if (error)
949                         goto fail;
950 
951                 start = e.pos;
952                 profile = unpack_profile(&e, &ns_name);
953                 if (IS_ERR(profile)) {
954                         error = PTR_ERR(profile);
955                         goto fail;
956                 }
957 
958                 error = verify_profile(profile);
959                 if (error)
960                         goto fail_profile;
961 
962                 if (aa_g_hash_policy)
963                         error = aa_calc_profile_hash(profile, e.version, start,
964                                                      e.pos - start);
965                 if (error)
966                         goto fail_profile;
967 
968                 ent = aa_load_ent_alloc();
969                 if (!ent) {
970                         error = -ENOMEM;
971                         goto fail_profile;
972                 }
973 
974                 ent->new = profile;
975                 ent->ns_name = ns_name;
976                 list_add_tail(&ent->list, lh);
977         }
978         udata->abi = e.version & K_ABI_MASK;
979         if (aa_g_hash_policy) {
980                 udata->hash = aa_calc_hash(udata->data, udata->size);
981                 if (IS_ERR(udata->hash)) {
982                         error = PTR_ERR(udata->hash);
983                         udata->hash = NULL;
984                         goto fail;
985                 }
986         }
987         return 0;
988 
989 fail_profile:
990         aa_put_profile(profile);
991 
992 fail:
993         list_for_each_entry_safe(ent, tmp, lh, list) {
994                 list_del_init(&ent->list);
995                 aa_load_ent_free(ent);
996         }
997 
998         return error;
999 }
1000 

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