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9
10
11#include <linux/errno.h>
12#include <linux/fdtable.h>
13#include <linux/fs.h>
14#include <linux/file.h>
15#include <linux/mount.h>
16#include <linux/syscalls.h>
17#include <linux/tracehook.h>
18#include <linux/personality.h>
19#include <linux/xattr.h>
20#include <linux/user_namespace.h>
21
22#include "include/audit.h"
23#include "include/apparmorfs.h"
24#include "include/cred.h"
25#include "include/domain.h"
26#include "include/file.h"
27#include "include/ipc.h"
28#include "include/match.h"
29#include "include/path.h"
30#include "include/policy.h"
31#include "include/policy_ns.h"
32
33
34
35
36
37void aa_free_domain_entries(struct aa_domain *domain)
38{
39 int i;
40 if (domain) {
41 if (!domain->table)
42 return;
43
44 for (i = 0; i < domain->size; i++)
45 kfree_sensitive(domain->table[i]);
46 kfree_sensitive(domain->table);
47 domain->table = NULL;
48 }
49}
50
51
52
53
54
55
56
57
58
59
60
61static int may_change_ptraced_domain(struct aa_label *to_label,
62 const char **info)
63{
64 struct task_struct *tracer;
65 struct aa_label *tracerl = NULL;
66 int error = 0;
67
68 rcu_read_lock();
69 tracer = ptrace_parent(current);
70 if (tracer)
71
72 tracerl = aa_get_task_label(tracer);
73
74
75 if (!tracer || unconfined(tracerl))
76 goto out;
77
78 error = aa_may_ptrace(tracerl, to_label, PTRACE_MODE_ATTACH);
79
80out:
81 rcu_read_unlock();
82 aa_put_label(tracerl);
83
84 if (error)
85 *info = "ptrace prevents transition";
86 return error;
87}
88
89
90
91
92
93
94
95
96
97
98
99static inline unsigned int match_component(struct aa_profile *profile,
100 struct aa_profile *tp,
101 bool stack, unsigned int state)
102{
103 const char *ns_name;
104
105 if (stack)
106 state = aa_dfa_match(profile->file.dfa, state, "&");
107 if (profile->ns == tp->ns)
108 return aa_dfa_match(profile->file.dfa, state, tp->base.hname);
109
110
111 ns_name = aa_ns_name(profile->ns, tp->ns, true);
112 state = aa_dfa_match_len(profile->file.dfa, state, ":", 1);
113 state = aa_dfa_match(profile->file.dfa, state, ns_name);
114 state = aa_dfa_match_len(profile->file.dfa, state, ":", 1);
115 return aa_dfa_match(profile->file.dfa, state, tp->base.hname);
116}
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134static int label_compound_match(struct aa_profile *profile,
135 struct aa_label *label, bool stack,
136 unsigned int state, bool subns, u32 request,
137 struct aa_perms *perms)
138{
139 struct aa_profile *tp;
140 struct label_it i;
141 struct path_cond cond = { };
142
143
144 label_for_each(i, label, tp) {
145 if (!aa_ns_visible(profile->ns, tp->ns, subns))
146 continue;
147 state = match_component(profile, tp, stack, state);
148 if (!state)
149 goto fail;
150 goto next;
151 }
152
153
154 *perms = allperms;
155 return 0;
156
157next:
158 label_for_each_cont(i, label, tp) {
159 if (!aa_ns_visible(profile->ns, tp->ns, subns))
160 continue;
161 state = aa_dfa_match(profile->file.dfa, state, "//&");
162 state = match_component(profile, tp, false, state);
163 if (!state)
164 goto fail;
165 }
166 *perms = aa_compute_fperms(profile->file.dfa, state, &cond);
167 aa_apply_modes_to_perms(profile, perms);
168 if ((perms->allow & request) != request)
169 return -EACCES;
170
171 return 0;
172
173fail:
174 *perms = nullperms;
175 return -EACCES;
176}
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194static int label_components_match(struct aa_profile *profile,
195 struct aa_label *label, bool stack,
196 unsigned int start, bool subns, u32 request,
197 struct aa_perms *perms)
198{
199 struct aa_profile *tp;
200 struct label_it i;
201 struct aa_perms tmp;
202 struct path_cond cond = { };
203 unsigned int state = 0;
204
205
206 label_for_each(i, label, tp) {
207 if (!aa_ns_visible(profile->ns, tp->ns, subns))
208 continue;
209 state = match_component(profile, tp, stack, start);
210 if (!state)
211 goto fail;
212 goto next;
213 }
214
215
216 return 0;
217
218next:
219 tmp = aa_compute_fperms(profile->file.dfa, state, &cond);
220 aa_apply_modes_to_perms(profile, &tmp);
221 aa_perms_accum(perms, &tmp);
222 label_for_each_cont(i, label, tp) {
223 if (!aa_ns_visible(profile->ns, tp->ns, subns))
224 continue;
225 state = match_component(profile, tp, stack, start);
226 if (!state)
227 goto fail;
228 tmp = aa_compute_fperms(profile->file.dfa, state, &cond);
229 aa_apply_modes_to_perms(profile, &tmp);
230 aa_perms_accum(perms, &tmp);
231 }
232
233 if ((perms->allow & request) != request)
234 return -EACCES;
235
236 return 0;
237
238fail:
239 *perms = nullperms;
240 return -EACCES;
241}
242
243
244
245
246
247
248
249
250
251
252
253
254
255static int label_match(struct aa_profile *profile, struct aa_label *label,
256 bool stack, unsigned int state, bool subns, u32 request,
257 struct aa_perms *perms)
258{
259 int error;
260
261 *perms = nullperms;
262 error = label_compound_match(profile, label, stack, state, subns,
263 request, perms);
264 if (!error)
265 return error;
266
267 *perms = allperms;
268 return label_components_match(profile, label, stack, state, subns,
269 request, perms);
270}
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288static int change_profile_perms(struct aa_profile *profile,
289 struct aa_label *target, bool stack,
290 u32 request, unsigned int start,
291 struct aa_perms *perms)
292{
293 if (profile_unconfined(profile)) {
294 perms->allow = AA_MAY_CHANGE_PROFILE | AA_MAY_ONEXEC;
295 perms->audit = perms->quiet = perms->kill = 0;
296 return 0;
297 }
298
299
300 return label_match(profile, target, stack, start, true, request, perms);
301}
302
303
304
305
306
307
308
309
310
311static int aa_xattrs_match(const struct linux_binprm *bprm,
312 struct aa_profile *profile, unsigned int state)
313{
314 int i;
315 ssize_t size;
316 struct dentry *d;
317 char *value = NULL;
318 int value_size = 0, ret = profile->xattr_count;
319
320 if (!bprm || !profile->xattr_count)
321 return 0;
322 might_sleep();
323
324
325 state = aa_dfa_outofband_transition(profile->xmatch, state);
326 d = bprm->file->f_path.dentry;
327
328 for (i = 0; i < profile->xattr_count; i++) {
329 size = vfs_getxattr_alloc(&init_user_ns, d, profile->xattrs[i],
330 &value, value_size, GFP_KERNEL);
331 if (size >= 0) {
332 u32 perm;
333
334
335
336
337
338
339 state = aa_dfa_null_transition(profile->xmatch, state);
340
341 state = aa_dfa_match_len(profile->xmatch, state, value,
342 size);
343 perm = dfa_user_allow(profile->xmatch, state);
344 if (!(perm & MAY_EXEC)) {
345 ret = -EINVAL;
346 goto out;
347 }
348 }
349
350 state = aa_dfa_outofband_transition(profile->xmatch, state);
351 if (size < 0) {
352
353
354
355
356
357 if (!state) {
358 ret = -EINVAL;
359 goto out;
360 }
361
362 ret--;
363 }
364 }
365
366out:
367 kfree(value);
368 return ret;
369}
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388static struct aa_label *find_attach(const struct linux_binprm *bprm,
389 struct aa_ns *ns, struct list_head *head,
390 const char *name, const char **info)
391{
392 int candidate_len = 0, candidate_xattrs = 0;
393 bool conflict = false;
394 struct aa_profile *profile, *candidate = NULL;
395
396 AA_BUG(!name);
397 AA_BUG(!head);
398
399 rcu_read_lock();
400restart:
401 list_for_each_entry_rcu(profile, head, base.list) {
402 if (profile->label.flags & FLAG_NULL &&
403 &profile->label == ns_unconfined(profile->ns))
404 continue;
405
406
407
408
409
410
411
412
413
414
415
416
417 if (profile->xmatch) {
418 unsigned int state, count;
419 u32 perm;
420
421 state = aa_dfa_leftmatch(profile->xmatch, DFA_START,
422 name, &count);
423 perm = dfa_user_allow(profile->xmatch, state);
424
425 if (perm & MAY_EXEC) {
426 int ret = 0;
427
428 if (count < candidate_len)
429 continue;
430
431 if (bprm && profile->xattr_count) {
432 long rev = READ_ONCE(ns->revision);
433
434 if (!aa_get_profile_not0(profile))
435 goto restart;
436 rcu_read_unlock();
437 ret = aa_xattrs_match(bprm, profile,
438 state);
439 rcu_read_lock();
440 aa_put_profile(profile);
441 if (rev !=
442 READ_ONCE(ns->revision))
443
444 goto restart;
445
446
447
448
449 if (ret < 0)
450 continue;
451 }
452
453
454
455
456
457
458 if (count == candidate_len &&
459 ret <= candidate_xattrs) {
460
461 if (ret == candidate_xattrs)
462 conflict = true;
463 continue;
464 }
465
466
467
468
469 candidate = profile;
470 candidate_len = profile->xmatch_len;
471 candidate_xattrs = ret;
472 conflict = false;
473 }
474 } else if (!strcmp(profile->base.name, name)) {
475
476
477
478
479 candidate = profile;
480 goto out;
481 }
482 }
483
484 if (!candidate || conflict) {
485 if (conflict)
486 *info = "conflicting profile attachments";
487 rcu_read_unlock();
488 return NULL;
489 }
490
491out:
492 candidate = aa_get_newest_profile(candidate);
493 rcu_read_unlock();
494
495 return &candidate->label;
496}
497
498static const char *next_name(int xtype, const char *name)
499{
500 return NULL;
501}
502
503
504
505
506
507
508
509
510
511struct aa_label *x_table_lookup(struct aa_profile *profile, u32 xindex,
512 const char **name)
513{
514 struct aa_label *label = NULL;
515 u32 xtype = xindex & AA_X_TYPE_MASK;
516 int index = xindex & AA_X_INDEX_MASK;
517
518 AA_BUG(!name);
519
520
521
522
523
524 for (*name = profile->file.trans.table[index]; !label && *name;
525 *name = next_name(xtype, *name)) {
526 if (xindex & AA_X_CHILD) {
527 struct aa_profile *new_profile;
528
529 new_profile = aa_find_child(profile, *name);
530 if (new_profile)
531 label = &new_profile->label;
532 continue;
533 }
534 label = aa_label_parse(&profile->label, *name, GFP_KERNEL,
535 true, false);
536 if (IS_ERR(label))
537 label = NULL;
538 }
539
540
541
542 return label;
543}
544
545
546
547
548
549
550
551
552
553
554
555
556
557static struct aa_label *x_to_label(struct aa_profile *profile,
558 const struct linux_binprm *bprm,
559 const char *name, u32 xindex,
560 const char **lookupname,
561 const char **info)
562{
563 struct aa_label *new = NULL;
564 struct aa_ns *ns = profile->ns;
565 u32 xtype = xindex & AA_X_TYPE_MASK;
566 const char *stack = NULL;
567
568 switch (xtype) {
569 case AA_X_NONE:
570
571 *lookupname = NULL;
572 break;
573 case AA_X_TABLE:
574
575 stack = profile->file.trans.table[xindex & AA_X_INDEX_MASK];
576 if (*stack != '&') {
577
578 new = x_table_lookup(profile, xindex, lookupname);
579 stack = NULL;
580 break;
581 }
582 fallthrough;
583 case AA_X_NAME:
584 if (xindex & AA_X_CHILD)
585
586 new = find_attach(bprm, ns, &profile->base.profiles,
587 name, info);
588 else
589
590 new = find_attach(bprm, ns, &ns->base.profiles,
591 name, info);
592 *lookupname = name;
593 break;
594 }
595
596 if (!new) {
597 if (xindex & AA_X_INHERIT) {
598
599
600
601 *info = "ix fallback";
602
603 new = aa_get_newest_label(&profile->label);
604 } else if (xindex & AA_X_UNCONFINED) {
605 new = aa_get_newest_label(ns_unconfined(profile->ns));
606 *info = "ux fallback";
607 }
608 }
609
610 if (new && stack) {
611
612 struct aa_label *base = new;
613
614 new = aa_label_parse(base, stack, GFP_KERNEL, true, false);
615 if (IS_ERR(new))
616 new = NULL;
617 aa_put_label(base);
618 }
619
620
621 return new;
622}
623
624static struct aa_label *profile_transition(struct aa_profile *profile,
625 const struct linux_binprm *bprm,
626 char *buffer, struct path_cond *cond,
627 bool *secure_exec)
628{
629 struct aa_label *new = NULL;
630 const char *info = NULL, *name = NULL, *target = NULL;
631 unsigned int state = profile->file.start;
632 struct aa_perms perms = {};
633 bool nonewprivs = false;
634 int error = 0;
635
636 AA_BUG(!profile);
637 AA_BUG(!bprm);
638 AA_BUG(!buffer);
639
640 error = aa_path_name(&bprm->file->f_path, profile->path_flags, buffer,
641 &name, &info, profile->disconnected);
642 if (error) {
643 if (profile_unconfined(profile) ||
644 (profile->label.flags & FLAG_IX_ON_NAME_ERROR)) {
645 AA_DEBUG("name lookup ix on error");
646 error = 0;
647 new = aa_get_newest_label(&profile->label);
648 }
649 name = bprm->filename;
650 goto audit;
651 }
652
653 if (profile_unconfined(profile)) {
654 new = find_attach(bprm, profile->ns,
655 &profile->ns->base.profiles, name, &info);
656 if (new) {
657 AA_DEBUG("unconfined attached to new label");
658 return new;
659 }
660 AA_DEBUG("unconfined exec no attachment");
661 return aa_get_newest_label(&profile->label);
662 }
663
664
665 state = aa_str_perms(profile->file.dfa, state, name, cond, &perms);
666 if (perms.allow & MAY_EXEC) {
667
668 new = x_to_label(profile, bprm, name, perms.xindex, &target,
669 &info);
670 if (new && new->proxy == profile->label.proxy && info) {
671
672 goto audit;
673 } else if (!new) {
674 error = -EACCES;
675 info = "profile transition not found";
676
677 perms.allow &= ~MAY_EXEC;
678 }
679 } else if (COMPLAIN_MODE(profile)) {
680
681 struct aa_profile *new_profile = NULL;
682
683 new_profile = aa_new_null_profile(profile, false, name,
684 GFP_KERNEL);
685 if (!new_profile) {
686 error = -ENOMEM;
687 info = "could not create null profile";
688 } else {
689 error = -EACCES;
690 new = &new_profile->label;
691 }
692 perms.xindex |= AA_X_UNSAFE;
693 } else
694
695 error = -EACCES;
696
697 if (!new)
698 goto audit;
699
700
701 if (!(perms.xindex & AA_X_UNSAFE)) {
702 if (DEBUG_ON) {
703 dbg_printk("apparmor: scrubbing environment variables"
704 " for %s profile=", name);
705 aa_label_printk(new, GFP_KERNEL);
706 dbg_printk("\n");
707 }
708 *secure_exec = true;
709 }
710
711audit:
712 aa_audit_file(profile, &perms, OP_EXEC, MAY_EXEC, name, target, new,
713 cond->uid, info, error);
714 if (!new || nonewprivs) {
715 aa_put_label(new);
716 return ERR_PTR(error);
717 }
718
719 return new;
720}
721
722static int profile_onexec(struct aa_profile *profile, struct aa_label *onexec,
723 bool stack, const struct linux_binprm *bprm,
724 char *buffer, struct path_cond *cond,
725 bool *secure_exec)
726{
727 unsigned int state = profile->file.start;
728 struct aa_perms perms = {};
729 const char *xname = NULL, *info = "change_profile onexec";
730 int error = -EACCES;
731
732 AA_BUG(!profile);
733 AA_BUG(!onexec);
734 AA_BUG(!bprm);
735 AA_BUG(!buffer);
736
737 if (profile_unconfined(profile)) {
738
739
740
741
742
743
744 return 0;
745 }
746
747 error = aa_path_name(&bprm->file->f_path, profile->path_flags, buffer,
748 &xname, &info, profile->disconnected);
749 if (error) {
750 if (profile_unconfined(profile) ||
751 (profile->label.flags & FLAG_IX_ON_NAME_ERROR)) {
752 AA_DEBUG("name lookup ix on error");
753 error = 0;
754 }
755 xname = bprm->filename;
756 goto audit;
757 }
758
759
760 state = aa_str_perms(profile->file.dfa, state, xname, cond, &perms);
761 if (!(perms.allow & AA_MAY_ONEXEC)) {
762 info = "no change_onexec valid for executable";
763 goto audit;
764 }
765
766
767
768
769 state = aa_dfa_null_transition(profile->file.dfa, state);
770 error = change_profile_perms(profile, onexec, stack, AA_MAY_ONEXEC,
771 state, &perms);
772 if (error) {
773 perms.allow &= ~AA_MAY_ONEXEC;
774 goto audit;
775 }
776
777 if (!(perms.xindex & AA_X_UNSAFE)) {
778 if (DEBUG_ON) {
779 dbg_printk("apparmor: scrubbing environment "
780 "variables for %s label=", xname);
781 aa_label_printk(onexec, GFP_KERNEL);
782 dbg_printk("\n");
783 }
784 *secure_exec = true;
785 }
786
787audit:
788 return aa_audit_file(profile, &perms, OP_EXEC, AA_MAY_ONEXEC, xname,
789 NULL, onexec, cond->uid, info, error);
790}
791
792
793
794static struct aa_label *handle_onexec(struct aa_label *label,
795 struct aa_label *onexec, bool stack,
796 const struct linux_binprm *bprm,
797 char *buffer, struct path_cond *cond,
798 bool *unsafe)
799{
800 struct aa_profile *profile;
801 struct aa_label *new;
802 int error;
803
804 AA_BUG(!label);
805 AA_BUG(!onexec);
806 AA_BUG(!bprm);
807 AA_BUG(!buffer);
808
809 if (!stack) {
810 error = fn_for_each_in_ns(label, profile,
811 profile_onexec(profile, onexec, stack,
812 bprm, buffer, cond, unsafe));
813 if (error)
814 return ERR_PTR(error);
815 new = fn_label_build_in_ns(label, profile, GFP_KERNEL,
816 aa_get_newest_label(onexec),
817 profile_transition(profile, bprm, buffer,
818 cond, unsafe));
819
820 } else {
821
822 error = fn_for_each_in_ns(label, profile,
823 profile_onexec(profile, onexec, stack, bprm,
824 buffer, cond, unsafe));
825 if (error)
826 return ERR_PTR(error);
827 new = fn_label_build_in_ns(label, profile, GFP_KERNEL,
828 aa_label_merge(&profile->label, onexec,
829 GFP_KERNEL),
830 profile_transition(profile, bprm, buffer,
831 cond, unsafe));
832 }
833
834 if (new)
835 return new;
836
837
838 error = fn_for_each_in_ns(label, profile,
839 aa_audit_file(profile, &nullperms, OP_CHANGE_ONEXEC,
840 AA_MAY_ONEXEC, bprm->filename, NULL,
841 onexec, GLOBAL_ROOT_UID,
842 "failed to build target label", -ENOMEM));
843 return ERR_PTR(error);
844}
845
846
847
848
849
850
851
852
853
854int apparmor_bprm_creds_for_exec(struct linux_binprm *bprm)
855{
856 struct aa_task_ctx *ctx;
857 struct aa_label *label, *new = NULL;
858 struct aa_profile *profile;
859 char *buffer = NULL;
860 const char *info = NULL;
861 int error = 0;
862 bool unsafe = false;
863 kuid_t i_uid = i_uid_into_mnt(file_mnt_user_ns(bprm->file),
864 file_inode(bprm->file));
865 struct path_cond cond = {
866 i_uid,
867 file_inode(bprm->file)->i_mode
868 };
869
870 ctx = task_ctx(current);
871 AA_BUG(!cred_label(bprm->cred));
872 AA_BUG(!ctx);
873
874 label = aa_get_newest_label(cred_label(bprm->cred));
875
876
877
878
879
880
881
882
883 if ((bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) && !unconfined(label) &&
884 !ctx->nnp)
885 ctx->nnp = aa_get_label(label);
886
887
888 buffer = aa_get_buffer(false);
889 if (!buffer) {
890 error = -ENOMEM;
891 goto done;
892 }
893
894
895 if (ctx->onexec)
896 new = handle_onexec(label, ctx->onexec, ctx->token,
897 bprm, buffer, &cond, &unsafe);
898 else
899 new = fn_label_build(label, profile, GFP_KERNEL,
900 profile_transition(profile, bprm, buffer,
901 &cond, &unsafe));
902
903 AA_BUG(!new);
904 if (IS_ERR(new)) {
905 error = PTR_ERR(new);
906 goto done;
907 } else if (!new) {
908 error = -ENOMEM;
909 goto done;
910 }
911
912
913
914
915
916
917
918
919
920 if ((bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) &&
921 !unconfined(label) &&
922 !aa_label_is_unconfined_subset(new, ctx->nnp)) {
923 error = -EPERM;
924 info = "no new privs";
925 goto audit;
926 }
927
928 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
929
930 ;
931 }
932
933 if (bprm->unsafe & (LSM_UNSAFE_PTRACE)) {
934
935 error = may_change_ptraced_domain(new, &info);
936 if (error)
937 goto audit;
938 }
939
940 if (unsafe) {
941 if (DEBUG_ON) {
942 dbg_printk("scrubbing environment variables for %s "
943 "label=", bprm->filename);
944 aa_label_printk(new, GFP_KERNEL);
945 dbg_printk("\n");
946 }
947 bprm->secureexec = 1;
948 }
949
950 if (label->proxy != new->proxy) {
951
952 if (DEBUG_ON) {
953 dbg_printk("apparmor: clearing unsafe personality "
954 "bits. %s label=", bprm->filename);
955 aa_label_printk(new, GFP_KERNEL);
956 dbg_printk("\n");
957 }
958 bprm->per_clear |= PER_CLEAR_ON_SETID;
959 }
960 aa_put_label(cred_label(bprm->cred));
961
962 set_cred_label(bprm->cred, new);
963
964done:
965 aa_put_label(label);
966 aa_put_buffer(buffer);
967
968 return error;
969
970audit:
971 error = fn_for_each(label, profile,
972 aa_audit_file(profile, &nullperms, OP_EXEC, MAY_EXEC,
973 bprm->filename, NULL, new,
974 i_uid, info, error));
975 aa_put_label(new);
976 goto done;
977}
978
979
980
981
982
983
984
985
986
987
988static struct aa_label *build_change_hat(struct aa_profile *profile,
989 const char *name, bool sibling)
990{
991 struct aa_profile *root, *hat = NULL;
992 const char *info = NULL;
993 int error = 0;
994
995 if (sibling && PROFILE_IS_HAT(profile)) {
996 root = aa_get_profile_rcu(&profile->parent);
997 } else if (!sibling && !PROFILE_IS_HAT(profile)) {
998 root = aa_get_profile(profile);
999 } else {
1000 info = "conflicting target types";
1001 error = -EPERM;
1002 goto audit;
1003 }
1004
1005 hat = aa_find_child(root, name);
1006 if (!hat) {
1007 error = -ENOENT;
1008 if (COMPLAIN_MODE(profile)) {
1009 hat = aa_new_null_profile(profile, true, name,
1010 GFP_KERNEL);
1011 if (!hat) {
1012 info = "failed null profile create";
1013 error = -ENOMEM;
1014 }
1015 }
1016 }
1017 aa_put_profile(root);
1018
1019audit:
1020 aa_audit_file(profile, &nullperms, OP_CHANGE_HAT, AA_MAY_CHANGEHAT,
1021 name, hat ? hat->base.hname : NULL,
1022 hat ? &hat->label : NULL, GLOBAL_ROOT_UID, info,
1023 error);
1024 if (!hat || (error && error != -ENOENT))
1025 return ERR_PTR(error);
1026
1027
1028
1029 return &hat->label;
1030}
1031
1032
1033
1034
1035
1036static struct aa_label *change_hat(struct aa_label *label, const char *hats[],
1037 int count, int flags)
1038{
1039 struct aa_profile *profile, *root, *hat = NULL;
1040 struct aa_label *new;
1041 struct label_it it;
1042 bool sibling = false;
1043 const char *name, *info = NULL;
1044 int i, error;
1045
1046 AA_BUG(!label);
1047 AA_BUG(!hats);
1048 AA_BUG(count < 1);
1049
1050 if (PROFILE_IS_HAT(labels_profile(label)))
1051 sibling = true;
1052
1053
1054 for (i = 0; i < count && !hat; i++) {
1055 name = hats[i];
1056 label_for_each_in_ns(it, labels_ns(label), label, profile) {
1057 if (sibling && PROFILE_IS_HAT(profile)) {
1058 root = aa_get_profile_rcu(&profile->parent);
1059 } else if (!sibling && !PROFILE_IS_HAT(profile)) {
1060 root = aa_get_profile(profile);
1061 } else {
1062 info = "conflicting targets types";
1063 error = -EPERM;
1064 goto fail;
1065 }
1066 hat = aa_find_child(root, name);
1067 aa_put_profile(root);
1068 if (!hat) {
1069 if (!COMPLAIN_MODE(profile))
1070 goto outer_continue;
1071
1072 } else if (!PROFILE_IS_HAT(hat)) {
1073 info = "target not hat";
1074 error = -EPERM;
1075 aa_put_profile(hat);
1076 goto fail;
1077 }
1078 aa_put_profile(hat);
1079 }
1080
1081 goto build;
1082outer_continue:
1083 ;
1084 }
1085
1086
1087
1088
1089
1090
1091 name = NULL;
1092 label_for_each_in_ns(it, labels_ns(label), label, profile) {
1093 if (!list_empty(&profile->base.profiles)) {
1094 info = "hat not found";
1095 error = -ENOENT;
1096 goto fail;
1097 }
1098 }
1099 info = "no hats defined";
1100 error = -ECHILD;
1101
1102fail:
1103 label_for_each_in_ns(it, labels_ns(label), label, profile) {
1104
1105
1106
1107
1108
1109
1110
1111 if (count > 1 || COMPLAIN_MODE(profile)) {
1112 aa_audit_file(profile, &nullperms, OP_CHANGE_HAT,
1113 AA_MAY_CHANGEHAT, name, NULL, NULL,
1114 GLOBAL_ROOT_UID, info, error);
1115 }
1116 }
1117 return ERR_PTR(error);
1118
1119build:
1120 new = fn_label_build_in_ns(label, profile, GFP_KERNEL,
1121 build_change_hat(profile, name, sibling),
1122 aa_get_label(&profile->label));
1123 if (!new) {
1124 info = "label build failed";
1125 error = -ENOMEM;
1126 goto fail;
1127 }
1128
1129 return new;
1130}
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149int aa_change_hat(const char *hats[], int count, u64 token, int flags)
1150{
1151 const struct cred *cred;
1152 struct aa_task_ctx *ctx = task_ctx(current);
1153 struct aa_label *label, *previous, *new = NULL, *target = NULL;
1154 struct aa_profile *profile;
1155 struct aa_perms perms = {};
1156 const char *info = NULL;
1157 int error = 0;
1158
1159
1160 cred = get_current_cred();
1161 label = aa_get_newest_cred_label(cred);
1162 previous = aa_get_newest_label(ctx->previous);
1163
1164
1165
1166
1167
1168
1169
1170
1171 if (task_no_new_privs(current) && !unconfined(label) && !ctx->nnp)
1172 ctx->nnp = aa_get_label(label);
1173
1174 if (unconfined(label)) {
1175 info = "unconfined can not change_hat";
1176 error = -EPERM;
1177 goto fail;
1178 }
1179
1180 if (count) {
1181 new = change_hat(label, hats, count, flags);
1182 AA_BUG(!new);
1183 if (IS_ERR(new)) {
1184 error = PTR_ERR(new);
1185 new = NULL;
1186
1187 goto out;
1188 }
1189
1190 error = may_change_ptraced_domain(new, &info);
1191 if (error)
1192 goto fail;
1193
1194
1195
1196
1197
1198 if (task_no_new_privs(current) && !unconfined(label) &&
1199 !aa_label_is_unconfined_subset(new, ctx->nnp)) {
1200
1201 AA_DEBUG("no_new_privs - change_hat denied");
1202 error = -EPERM;
1203 goto out;
1204 }
1205
1206 if (flags & AA_CHANGE_TEST)
1207 goto out;
1208
1209 target = new;
1210 error = aa_set_current_hat(new, token);
1211 if (error == -EACCES)
1212
1213 goto kill;
1214 } else if (previous && !(flags & AA_CHANGE_TEST)) {
1215
1216
1217
1218
1219 if (task_no_new_privs(current) && !unconfined(label) &&
1220 !aa_label_is_unconfined_subset(previous, ctx->nnp)) {
1221
1222 AA_DEBUG("no_new_privs - change_hat denied");
1223 error = -EPERM;
1224 goto out;
1225 }
1226
1227
1228
1229
1230 target = previous;
1231 error = aa_restore_previous_label(token);
1232 if (error) {
1233 if (error == -EACCES)
1234 goto kill;
1235 goto fail;
1236 }
1237 }
1238
1239out:
1240 aa_put_label(new);
1241 aa_put_label(previous);
1242 aa_put_label(label);
1243 put_cred(cred);
1244
1245 return error;
1246
1247kill:
1248 info = "failed token match";
1249 perms.kill = AA_MAY_CHANGEHAT;
1250
1251fail:
1252 fn_for_each_in_ns(label, profile,
1253 aa_audit_file(profile, &perms, OP_CHANGE_HAT,
1254 AA_MAY_CHANGEHAT, NULL, NULL, target,
1255 GLOBAL_ROOT_UID, info, error));
1256
1257 goto out;
1258}
1259
1260
1261static int change_profile_perms_wrapper(const char *op, const char *name,
1262 struct aa_profile *profile,
1263 struct aa_label *target, bool stack,
1264 u32 request, struct aa_perms *perms)
1265{
1266 const char *info = NULL;
1267 int error = 0;
1268
1269 if (!error)
1270 error = change_profile_perms(profile, target, stack, request,
1271 profile->file.start, perms);
1272 if (error)
1273 error = aa_audit_file(profile, perms, op, request, name,
1274 NULL, target, GLOBAL_ROOT_UID, info,
1275 error);
1276
1277 return error;
1278}
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294int aa_change_profile(const char *fqname, int flags)
1295{
1296 struct aa_label *label, *new = NULL, *target = NULL;
1297 struct aa_profile *profile;
1298 struct aa_perms perms = {};
1299 const char *info = NULL;
1300 const char *auditname = fqname;
1301 bool stack = flags & AA_CHANGE_STACK;
1302 struct aa_task_ctx *ctx = task_ctx(current);
1303 int error = 0;
1304 char *op;
1305 u32 request;
1306
1307 label = aa_get_current_label();
1308
1309
1310
1311
1312
1313
1314
1315
1316 if (task_no_new_privs(current) && !unconfined(label) && !ctx->nnp)
1317 ctx->nnp = aa_get_label(label);
1318
1319 if (!fqname || !*fqname) {
1320 aa_put_label(label);
1321 AA_DEBUG("no profile name");
1322 return -EINVAL;
1323 }
1324
1325 if (flags & AA_CHANGE_ONEXEC) {
1326 request = AA_MAY_ONEXEC;
1327 if (stack)
1328 op = OP_STACK_ONEXEC;
1329 else
1330 op = OP_CHANGE_ONEXEC;
1331 } else {
1332 request = AA_MAY_CHANGE_PROFILE;
1333 if (stack)
1334 op = OP_STACK;
1335 else
1336 op = OP_CHANGE_PROFILE;
1337 }
1338
1339 if (*fqname == '&') {
1340 stack = true;
1341
1342 fqname++;
1343 }
1344 target = aa_label_parse(label, fqname, GFP_KERNEL, true, false);
1345 if (IS_ERR(target)) {
1346 struct aa_profile *tprofile;
1347
1348 info = "label not found";
1349 error = PTR_ERR(target);
1350 target = NULL;
1351
1352
1353
1354
1355 if ((flags & AA_CHANGE_TEST) ||
1356 !COMPLAIN_MODE(labels_profile(label)))
1357 goto audit;
1358
1359 tprofile = aa_new_null_profile(labels_profile(label), false,
1360 fqname, GFP_KERNEL);
1361 if (!tprofile) {
1362 info = "failed null profile create";
1363 error = -ENOMEM;
1364 goto audit;
1365 }
1366 target = &tprofile->label;
1367 goto check;
1368 }
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378 error = fn_for_each_in_ns(label, profile,
1379 change_profile_perms_wrapper(op, auditname,
1380 profile, target, stack,
1381 request, &perms));
1382 if (error)
1383
1384 goto out;
1385
1386
1387
1388check:
1389
1390 error = may_change_ptraced_domain(target, &info);
1391 if (error && !fn_for_each_in_ns(label, profile,
1392 COMPLAIN_MODE(profile)))
1393 goto audit;
1394
1395
1396
1397
1398
1399
1400
1401
1402 if (flags & AA_CHANGE_TEST)
1403 goto out;
1404
1405
1406 if (!stack) {
1407 new = fn_label_build_in_ns(label, profile, GFP_KERNEL,
1408 aa_get_label(target),
1409 aa_get_label(&profile->label));
1410
1411
1412
1413
1414 if (task_no_new_privs(current) && !unconfined(label) &&
1415 !aa_label_is_unconfined_subset(new, ctx->nnp)) {
1416
1417 AA_DEBUG("no_new_privs - change_hat denied");
1418 error = -EPERM;
1419 goto out;
1420 }
1421 }
1422
1423 if (!(flags & AA_CHANGE_ONEXEC)) {
1424
1425 if (stack)
1426 new = aa_label_merge(label, target, GFP_KERNEL);
1427 if (IS_ERR_OR_NULL(new)) {
1428 info = "failed to build target label";
1429 if (!new)
1430 error = -ENOMEM;
1431 else
1432 error = PTR_ERR(new);
1433 new = NULL;
1434 perms.allow = 0;
1435 goto audit;
1436 }
1437 error = aa_replace_current_label(new);
1438 } else {
1439 if (new) {
1440 aa_put_label(new);
1441 new = NULL;
1442 }
1443
1444
1445 error = aa_set_current_onexec(target, stack);
1446 }
1447
1448audit:
1449 error = fn_for_each_in_ns(label, profile,
1450 aa_audit_file(profile, &perms, op, request, auditname,
1451 NULL, new ? new : target,
1452 GLOBAL_ROOT_UID, info, error));
1453
1454out:
1455 aa_put_label(new);
1456 aa_put_label(target);
1457 aa_put_label(label);
1458
1459 return error;
1460}
1461