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1 | /* auditsc.c -- System-call auditing support | |
2 | * Handles all system-call specific auditing features. | |
3 | * | |
4 | * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina. | |
5 | * Copyright 2005 Hewlett-Packard Development Company, L.P. | |
6 | * Copyright (C) 2005, 2006 IBM Corporation | |
7 | * All Rights Reserved. | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation; either version 2 of the License, or | |
12 | * (at your option) any later version. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | * | |
19 | * You should have received a copy of the GNU General Public License | |
20 | * along with this program; if not, write to the Free Software | |
21 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
22 | * | |
23 | * Written by Rickard E. (Rik) Faith <faith@redhat.com> | |
24 | * | |
25 | * Many of the ideas implemented here are from Stephen C. Tweedie, | |
26 | * especially the idea of avoiding a copy by using getname. | |
27 | * | |
28 | * The method for actual interception of syscall entry and exit (not in | |
29 | * this file -- see entry.S) is based on a GPL'd patch written by | |
30 | * okir@suse.de and Copyright 2003 SuSE Linux AG. | |
31 | * | |
32 | * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>, | |
33 | * 2006. | |
34 | * | |
35 | * The support of additional filter rules compares (>, <, >=, <=) was | |
36 | * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005. | |
37 | * | |
38 | * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional | |
39 | * filesystem information. | |
40 | * | |
41 | * Subject and object context labeling support added by <danjones@us.ibm.com> | |
42 | * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance. | |
43 | */ | |
44 | ||
45 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
46 | ||
47 | #include <linux/init.h> | |
48 | #include <asm/types.h> | |
49 | #include <linux/atomic.h> | |
50 | #include <linux/fs.h> | |
51 | #include <linux/namei.h> | |
52 | #include <linux/mm.h> | |
53 | #include <linux/export.h> | |
54 | #include <linux/slab.h> | |
55 | #include <linux/mount.h> | |
56 | #include <linux/socket.h> | |
57 | #include <linux/mqueue.h> | |
58 | #include <linux/audit.h> | |
59 | #include <linux/personality.h> | |
60 | #include <linux/time.h> | |
61 | #include <linux/netlink.h> | |
62 | #include <linux/compiler.h> | |
63 | #include <asm/unistd.h> | |
64 | #include <linux/security.h> | |
65 | #include <linux/list.h> | |
66 | #include <linux/binfmts.h> | |
67 | #include <linux/highmem.h> | |
68 | #include <linux/syscalls.h> | |
69 | #include <asm/syscall.h> | |
70 | #include <linux/capability.h> | |
71 | #include <linux/fs_struct.h> | |
72 | #include <linux/compat.h> | |
73 | #include <linux/ctype.h> | |
74 | #include <linux/string.h> | |
75 | #include <linux/uaccess.h> | |
76 | #include <linux/fsnotify_backend.h> | |
77 | #include <uapi/linux/limits.h> | |
78 | ||
79 | #include "audit.h" | |
80 | ||
81 | /* flags stating the success for a syscall */ | |
82 | #define AUDITSC_INVALID 0 | |
83 | #define AUDITSC_SUCCESS 1 | |
84 | #define AUDITSC_FAILURE 2 | |
85 | ||
86 | /* no execve audit message should be longer than this (userspace limits), | |
87 | * see the note near the top of audit_log_execve_info() about this value */ | |
88 | #define MAX_EXECVE_AUDIT_LEN 7500 | |
89 | ||
90 | /* max length to print of cmdline/proctitle value during audit */ | |
91 | #define MAX_PROCTITLE_AUDIT_LEN 128 | |
92 | ||
93 | /* number of audit rules */ | |
94 | int audit_n_rules; | |
95 | ||
96 | /* determines whether we collect data for signals sent */ | |
97 | int audit_signals; | |
98 | ||
99 | struct audit_aux_data { | |
100 | struct audit_aux_data *next; | |
101 | int type; | |
102 | }; | |
103 | ||
104 | #define AUDIT_AUX_IPCPERM 0 | |
105 | ||
106 | /* Number of target pids per aux struct. */ | |
107 | #define AUDIT_AUX_PIDS 16 | |
108 | ||
109 | struct audit_aux_data_pids { | |
110 | struct audit_aux_data d; | |
111 | pid_t target_pid[AUDIT_AUX_PIDS]; | |
112 | kuid_t target_auid[AUDIT_AUX_PIDS]; | |
113 | kuid_t target_uid[AUDIT_AUX_PIDS]; | |
114 | unsigned int target_sessionid[AUDIT_AUX_PIDS]; | |
115 | u32 target_sid[AUDIT_AUX_PIDS]; | |
116 | char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; | |
117 | int pid_count; | |
118 | }; | |
119 | ||
120 | struct audit_aux_data_bprm_fcaps { | |
121 | struct audit_aux_data d; | |
122 | struct audit_cap_data fcap; | |
123 | unsigned int fcap_ver; | |
124 | struct audit_cap_data old_pcap; | |
125 | struct audit_cap_data new_pcap; | |
126 | }; | |
127 | ||
128 | struct audit_tree_refs { | |
129 | struct audit_tree_refs *next; | |
130 | struct audit_chunk *c[31]; | |
131 | }; | |
132 | ||
133 | static int audit_match_perm(struct audit_context *ctx, int mask) | |
134 | { | |
135 | unsigned n; | |
136 | if (unlikely(!ctx)) | |
137 | return 0; | |
138 | n = ctx->major; | |
139 | ||
140 | switch (audit_classify_syscall(ctx->arch, n)) { | |
141 | case 0: /* native */ | |
142 | if ((mask & AUDIT_PERM_WRITE) && | |
143 | audit_match_class(AUDIT_CLASS_WRITE, n)) | |
144 | return 1; | |
145 | if ((mask & AUDIT_PERM_READ) && | |
146 | audit_match_class(AUDIT_CLASS_READ, n)) | |
147 | return 1; | |
148 | if ((mask & AUDIT_PERM_ATTR) && | |
149 | audit_match_class(AUDIT_CLASS_CHATTR, n)) | |
150 | return 1; | |
151 | return 0; | |
152 | case 1: /* 32bit on biarch */ | |
153 | if ((mask & AUDIT_PERM_WRITE) && | |
154 | audit_match_class(AUDIT_CLASS_WRITE_32, n)) | |
155 | return 1; | |
156 | if ((mask & AUDIT_PERM_READ) && | |
157 | audit_match_class(AUDIT_CLASS_READ_32, n)) | |
158 | return 1; | |
159 | if ((mask & AUDIT_PERM_ATTR) && | |
160 | audit_match_class(AUDIT_CLASS_CHATTR_32, n)) | |
161 | return 1; | |
162 | return 0; | |
163 | case 2: /* open */ | |
164 | return mask & ACC_MODE(ctx->argv[1]); | |
165 | case 3: /* openat */ | |
166 | return mask & ACC_MODE(ctx->argv[2]); | |
167 | case 4: /* socketcall */ | |
168 | return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); | |
169 | case 5: /* execve */ | |
170 | return mask & AUDIT_PERM_EXEC; | |
171 | default: | |
172 | return 0; | |
173 | } | |
174 | } | |
175 | ||
176 | static int audit_match_filetype(struct audit_context *ctx, int val) | |
177 | { | |
178 | struct audit_names *n; | |
179 | umode_t mode = (umode_t)val; | |
180 | ||
181 | if (unlikely(!ctx)) | |
182 | return 0; | |
183 | ||
184 | list_for_each_entry(n, &ctx->names_list, list) { | |
185 | if ((n->ino != AUDIT_INO_UNSET) && | |
186 | ((n->mode & S_IFMT) == mode)) | |
187 | return 1; | |
188 | } | |
189 | ||
190 | return 0; | |
191 | } | |
192 | ||
193 | /* | |
194 | * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; | |
195 | * ->first_trees points to its beginning, ->trees - to the current end of data. | |
196 | * ->tree_count is the number of free entries in array pointed to by ->trees. | |
197 | * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, | |
198 | * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, | |
199 | * it's going to remain 1-element for almost any setup) until we free context itself. | |
200 | * References in it _are_ dropped - at the same time we free/drop aux stuff. | |
201 | */ | |
202 | ||
203 | #ifdef CONFIG_AUDIT_TREE | |
204 | static void audit_set_auditable(struct audit_context *ctx) | |
205 | { | |
206 | if (!ctx->prio) { | |
207 | ctx->prio = 1; | |
208 | ctx->current_state = AUDIT_RECORD_CONTEXT; | |
209 | } | |
210 | } | |
211 | ||
212 | static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) | |
213 | { | |
214 | struct audit_tree_refs *p = ctx->trees; | |
215 | int left = ctx->tree_count; | |
216 | if (likely(left)) { | |
217 | p->c[--left] = chunk; | |
218 | ctx->tree_count = left; | |
219 | return 1; | |
220 | } | |
221 | if (!p) | |
222 | return 0; | |
223 | p = p->next; | |
224 | if (p) { | |
225 | p->c[30] = chunk; | |
226 | ctx->trees = p; | |
227 | ctx->tree_count = 30; | |
228 | return 1; | |
229 | } | |
230 | return 0; | |
231 | } | |
232 | ||
233 | static int grow_tree_refs(struct audit_context *ctx) | |
234 | { | |
235 | struct audit_tree_refs *p = ctx->trees; | |
236 | ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); | |
237 | if (!ctx->trees) { | |
238 | ctx->trees = p; | |
239 | return 0; | |
240 | } | |
241 | if (p) | |
242 | p->next = ctx->trees; | |
243 | else | |
244 | ctx->first_trees = ctx->trees; | |
245 | ctx->tree_count = 31; | |
246 | return 1; | |
247 | } | |
248 | #endif | |
249 | ||
250 | static void unroll_tree_refs(struct audit_context *ctx, | |
251 | struct audit_tree_refs *p, int count) | |
252 | { | |
253 | #ifdef CONFIG_AUDIT_TREE | |
254 | struct audit_tree_refs *q; | |
255 | int n; | |
256 | if (!p) { | |
257 | /* we started with empty chain */ | |
258 | p = ctx->first_trees; | |
259 | count = 31; | |
260 | /* if the very first allocation has failed, nothing to do */ | |
261 | if (!p) | |
262 | return; | |
263 | } | |
264 | n = count; | |
265 | for (q = p; q != ctx->trees; q = q->next, n = 31) { | |
266 | while (n--) { | |
267 | audit_put_chunk(q->c[n]); | |
268 | q->c[n] = NULL; | |
269 | } | |
270 | } | |
271 | while (n-- > ctx->tree_count) { | |
272 | audit_put_chunk(q->c[n]); | |
273 | q->c[n] = NULL; | |
274 | } | |
275 | ctx->trees = p; | |
276 | ctx->tree_count = count; | |
277 | #endif | |
278 | } | |
279 | ||
280 | static void free_tree_refs(struct audit_context *ctx) | |
281 | { | |
282 | struct audit_tree_refs *p, *q; | |
283 | for (p = ctx->first_trees; p; p = q) { | |
284 | q = p->next; | |
285 | kfree(p); | |
286 | } | |
287 | } | |
288 | ||
289 | static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) | |
290 | { | |
291 | #ifdef CONFIG_AUDIT_TREE | |
292 | struct audit_tree_refs *p; | |
293 | int n; | |
294 | if (!tree) | |
295 | return 0; | |
296 | /* full ones */ | |
297 | for (p = ctx->first_trees; p != ctx->trees; p = p->next) { | |
298 | for (n = 0; n < 31; n++) | |
299 | if (audit_tree_match(p->c[n], tree)) | |
300 | return 1; | |
301 | } | |
302 | /* partial */ | |
303 | if (p) { | |
304 | for (n = ctx->tree_count; n < 31; n++) | |
305 | if (audit_tree_match(p->c[n], tree)) | |
306 | return 1; | |
307 | } | |
308 | #endif | |
309 | return 0; | |
310 | } | |
311 | ||
312 | static int audit_compare_uid(kuid_t uid, | |
313 | struct audit_names *name, | |
314 | struct audit_field *f, | |
315 | struct audit_context *ctx) | |
316 | { | |
317 | struct audit_names *n; | |
318 | int rc; | |
319 | ||
320 | if (name) { | |
321 | rc = audit_uid_comparator(uid, f->op, name->uid); | |
322 | if (rc) | |
323 | return rc; | |
324 | } | |
325 | ||
326 | if (ctx) { | |
327 | list_for_each_entry(n, &ctx->names_list, list) { | |
328 | rc = audit_uid_comparator(uid, f->op, n->uid); | |
329 | if (rc) | |
330 | return rc; | |
331 | } | |
332 | } | |
333 | return 0; | |
334 | } | |
335 | ||
336 | static int audit_compare_gid(kgid_t gid, | |
337 | struct audit_names *name, | |
338 | struct audit_field *f, | |
339 | struct audit_context *ctx) | |
340 | { | |
341 | struct audit_names *n; | |
342 | int rc; | |
343 | ||
344 | if (name) { | |
345 | rc = audit_gid_comparator(gid, f->op, name->gid); | |
346 | if (rc) | |
347 | return rc; | |
348 | } | |
349 | ||
350 | if (ctx) { | |
351 | list_for_each_entry(n, &ctx->names_list, list) { | |
352 | rc = audit_gid_comparator(gid, f->op, n->gid); | |
353 | if (rc) | |
354 | return rc; | |
355 | } | |
356 | } | |
357 | return 0; | |
358 | } | |
359 | ||
360 | static int audit_field_compare(struct task_struct *tsk, | |
361 | const struct cred *cred, | |
362 | struct audit_field *f, | |
363 | struct audit_context *ctx, | |
364 | struct audit_names *name) | |
365 | { | |
366 | switch (f->val) { | |
367 | /* process to file object comparisons */ | |
368 | case AUDIT_COMPARE_UID_TO_OBJ_UID: | |
369 | return audit_compare_uid(cred->uid, name, f, ctx); | |
370 | case AUDIT_COMPARE_GID_TO_OBJ_GID: | |
371 | return audit_compare_gid(cred->gid, name, f, ctx); | |
372 | case AUDIT_COMPARE_EUID_TO_OBJ_UID: | |
373 | return audit_compare_uid(cred->euid, name, f, ctx); | |
374 | case AUDIT_COMPARE_EGID_TO_OBJ_GID: | |
375 | return audit_compare_gid(cred->egid, name, f, ctx); | |
376 | case AUDIT_COMPARE_AUID_TO_OBJ_UID: | |
377 | return audit_compare_uid(tsk->loginuid, name, f, ctx); | |
378 | case AUDIT_COMPARE_SUID_TO_OBJ_UID: | |
379 | return audit_compare_uid(cred->suid, name, f, ctx); | |
380 | case AUDIT_COMPARE_SGID_TO_OBJ_GID: | |
381 | return audit_compare_gid(cred->sgid, name, f, ctx); | |
382 | case AUDIT_COMPARE_FSUID_TO_OBJ_UID: | |
383 | return audit_compare_uid(cred->fsuid, name, f, ctx); | |
384 | case AUDIT_COMPARE_FSGID_TO_OBJ_GID: | |
385 | return audit_compare_gid(cred->fsgid, name, f, ctx); | |
386 | /* uid comparisons */ | |
387 | case AUDIT_COMPARE_UID_TO_AUID: | |
388 | return audit_uid_comparator(cred->uid, f->op, tsk->loginuid); | |
389 | case AUDIT_COMPARE_UID_TO_EUID: | |
390 | return audit_uid_comparator(cred->uid, f->op, cred->euid); | |
391 | case AUDIT_COMPARE_UID_TO_SUID: | |
392 | return audit_uid_comparator(cred->uid, f->op, cred->suid); | |
393 | case AUDIT_COMPARE_UID_TO_FSUID: | |
394 | return audit_uid_comparator(cred->uid, f->op, cred->fsuid); | |
395 | /* auid comparisons */ | |
396 | case AUDIT_COMPARE_AUID_TO_EUID: | |
397 | return audit_uid_comparator(tsk->loginuid, f->op, cred->euid); | |
398 | case AUDIT_COMPARE_AUID_TO_SUID: | |
399 | return audit_uid_comparator(tsk->loginuid, f->op, cred->suid); | |
400 | case AUDIT_COMPARE_AUID_TO_FSUID: | |
401 | return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid); | |
402 | /* euid comparisons */ | |
403 | case AUDIT_COMPARE_EUID_TO_SUID: | |
404 | return audit_uid_comparator(cred->euid, f->op, cred->suid); | |
405 | case AUDIT_COMPARE_EUID_TO_FSUID: | |
406 | return audit_uid_comparator(cred->euid, f->op, cred->fsuid); | |
407 | /* suid comparisons */ | |
408 | case AUDIT_COMPARE_SUID_TO_FSUID: | |
409 | return audit_uid_comparator(cred->suid, f->op, cred->fsuid); | |
410 | /* gid comparisons */ | |
411 | case AUDIT_COMPARE_GID_TO_EGID: | |
412 | return audit_gid_comparator(cred->gid, f->op, cred->egid); | |
413 | case AUDIT_COMPARE_GID_TO_SGID: | |
414 | return audit_gid_comparator(cred->gid, f->op, cred->sgid); | |
415 | case AUDIT_COMPARE_GID_TO_FSGID: | |
416 | return audit_gid_comparator(cred->gid, f->op, cred->fsgid); | |
417 | /* egid comparisons */ | |
418 | case AUDIT_COMPARE_EGID_TO_SGID: | |
419 | return audit_gid_comparator(cred->egid, f->op, cred->sgid); | |
420 | case AUDIT_COMPARE_EGID_TO_FSGID: | |
421 | return audit_gid_comparator(cred->egid, f->op, cred->fsgid); | |
422 | /* sgid comparison */ | |
423 | case AUDIT_COMPARE_SGID_TO_FSGID: | |
424 | return audit_gid_comparator(cred->sgid, f->op, cred->fsgid); | |
425 | default: | |
426 | WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); | |
427 | return 0; | |
428 | } | |
429 | return 0; | |
430 | } | |
431 | ||
432 | /* Determine if any context name data matches a rule's watch data */ | |
433 | /* Compare a task_struct with an audit_rule. Return 1 on match, 0 | |
434 | * otherwise. | |
435 | * | |
436 | * If task_creation is true, this is an explicit indication that we are | |
437 | * filtering a task rule at task creation time. This and tsk == current are | |
438 | * the only situations where tsk->cred may be accessed without an rcu read lock. | |
439 | */ | |
440 | static int audit_filter_rules(struct task_struct *tsk, | |
441 | struct audit_krule *rule, | |
442 | struct audit_context *ctx, | |
443 | struct audit_names *name, | |
444 | enum audit_state *state, | |
445 | bool task_creation) | |
446 | { | |
447 | const struct cred *cred; | |
448 | int i, need_sid = 1; | |
449 | u32 sid; | |
450 | unsigned int sessionid; | |
451 | ||
452 | cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); | |
453 | ||
454 | for (i = 0; i < rule->field_count; i++) { | |
455 | struct audit_field *f = &rule->fields[i]; | |
456 | struct audit_names *n; | |
457 | int result = 0; | |
458 | pid_t pid; | |
459 | ||
460 | switch (f->type) { | |
461 | case AUDIT_PID: | |
462 | pid = task_tgid_nr(tsk); | |
463 | result = audit_comparator(pid, f->op, f->val); | |
464 | break; | |
465 | case AUDIT_PPID: | |
466 | if (ctx) { | |
467 | if (!ctx->ppid) | |
468 | ctx->ppid = task_ppid_nr(tsk); | |
469 | result = audit_comparator(ctx->ppid, f->op, f->val); | |
470 | } | |
471 | break; | |
472 | case AUDIT_EXE: | |
473 | result = audit_exe_compare(tsk, rule->exe); | |
474 | break; | |
475 | case AUDIT_UID: | |
476 | result = audit_uid_comparator(cred->uid, f->op, f->uid); | |
477 | break; | |
478 | case AUDIT_EUID: | |
479 | result = audit_uid_comparator(cred->euid, f->op, f->uid); | |
480 | break; | |
481 | case AUDIT_SUID: | |
482 | result = audit_uid_comparator(cred->suid, f->op, f->uid); | |
483 | break; | |
484 | case AUDIT_FSUID: | |
485 | result = audit_uid_comparator(cred->fsuid, f->op, f->uid); | |
486 | break; | |
487 | case AUDIT_GID: | |
488 | result = audit_gid_comparator(cred->gid, f->op, f->gid); | |
489 | if (f->op == Audit_equal) { | |
490 | if (!result) | |
491 | result = in_group_p(f->gid); | |
492 | } else if (f->op == Audit_not_equal) { | |
493 | if (result) | |
494 | result = !in_group_p(f->gid); | |
495 | } | |
496 | break; | |
497 | case AUDIT_EGID: | |
498 | result = audit_gid_comparator(cred->egid, f->op, f->gid); | |
499 | if (f->op == Audit_equal) { | |
500 | if (!result) | |
501 | result = in_egroup_p(f->gid); | |
502 | } else if (f->op == Audit_not_equal) { | |
503 | if (result) | |
504 | result = !in_egroup_p(f->gid); | |
505 | } | |
506 | break; | |
507 | case AUDIT_SGID: | |
508 | result = audit_gid_comparator(cred->sgid, f->op, f->gid); | |
509 | break; | |
510 | case AUDIT_FSGID: | |
511 | result = audit_gid_comparator(cred->fsgid, f->op, f->gid); | |
512 | break; | |
513 | case AUDIT_SESSIONID: | |
514 | sessionid = audit_get_sessionid(current); | |
515 | result = audit_comparator(sessionid, f->op, f->val); | |
516 | break; | |
517 | case AUDIT_PERS: | |
518 | result = audit_comparator(tsk->personality, f->op, f->val); | |
519 | break; | |
520 | case AUDIT_ARCH: | |
521 | if (ctx) | |
522 | result = audit_comparator(ctx->arch, f->op, f->val); | |
523 | break; | |
524 | ||
525 | case AUDIT_EXIT: | |
526 | if (ctx && ctx->return_valid) | |
527 | result = audit_comparator(ctx->return_code, f->op, f->val); | |
528 | break; | |
529 | case AUDIT_SUCCESS: | |
530 | if (ctx && ctx->return_valid) { | |
531 | if (f->val) | |
532 | result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); | |
533 | else | |
534 | result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); | |
535 | } | |
536 | break; | |
537 | case AUDIT_DEVMAJOR: | |
538 | if (name) { | |
539 | if (audit_comparator(MAJOR(name->dev), f->op, f->val) || | |
540 | audit_comparator(MAJOR(name->rdev), f->op, f->val)) | |
541 | ++result; | |
542 | } else if (ctx) { | |
543 | list_for_each_entry(n, &ctx->names_list, list) { | |
544 | if (audit_comparator(MAJOR(n->dev), f->op, f->val) || | |
545 | audit_comparator(MAJOR(n->rdev), f->op, f->val)) { | |
546 | ++result; | |
547 | break; | |
548 | } | |
549 | } | |
550 | } | |
551 | break; | |
552 | case AUDIT_DEVMINOR: | |
553 | if (name) { | |
554 | if (audit_comparator(MINOR(name->dev), f->op, f->val) || | |
555 | audit_comparator(MINOR(name->rdev), f->op, f->val)) | |
556 | ++result; | |
557 | } else if (ctx) { | |
558 | list_for_each_entry(n, &ctx->names_list, list) { | |
559 | if (audit_comparator(MINOR(n->dev), f->op, f->val) || | |
560 | audit_comparator(MINOR(n->rdev), f->op, f->val)) { | |
561 | ++result; | |
562 | break; | |
563 | } | |
564 | } | |
565 | } | |
566 | break; | |
567 | case AUDIT_INODE: | |
568 | if (name) | |
569 | result = audit_comparator(name->ino, f->op, f->val); | |
570 | else if (ctx) { | |
571 | list_for_each_entry(n, &ctx->names_list, list) { | |
572 | if (audit_comparator(n->ino, f->op, f->val)) { | |
573 | ++result; | |
574 | break; | |
575 | } | |
576 | } | |
577 | } | |
578 | break; | |
579 | case AUDIT_OBJ_UID: | |
580 | if (name) { | |
581 | result = audit_uid_comparator(name->uid, f->op, f->uid); | |
582 | } else if (ctx) { | |
583 | list_for_each_entry(n, &ctx->names_list, list) { | |
584 | if (audit_uid_comparator(n->uid, f->op, f->uid)) { | |
585 | ++result; | |
586 | break; | |
587 | } | |
588 | } | |
589 | } | |
590 | break; | |
591 | case AUDIT_OBJ_GID: | |
592 | if (name) { | |
593 | result = audit_gid_comparator(name->gid, f->op, f->gid); | |
594 | } else if (ctx) { | |
595 | list_for_each_entry(n, &ctx->names_list, list) { | |
596 | if (audit_gid_comparator(n->gid, f->op, f->gid)) { | |
597 | ++result; | |
598 | break; | |
599 | } | |
600 | } | |
601 | } | |
602 | break; | |
603 | case AUDIT_WATCH: | |
604 | if (name) | |
605 | result = audit_watch_compare(rule->watch, name->ino, name->dev); | |
606 | break; | |
607 | case AUDIT_DIR: | |
608 | if (ctx) | |
609 | result = match_tree_refs(ctx, rule->tree); | |
610 | break; | |
611 | case AUDIT_LOGINUID: | |
612 | result = audit_uid_comparator(tsk->loginuid, f->op, f->uid); | |
613 | break; | |
614 | case AUDIT_LOGINUID_SET: | |
615 | result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val); | |
616 | break; | |
617 | case AUDIT_SUBJ_USER: | |
618 | case AUDIT_SUBJ_ROLE: | |
619 | case AUDIT_SUBJ_TYPE: | |
620 | case AUDIT_SUBJ_SEN: | |
621 | case AUDIT_SUBJ_CLR: | |
622 | /* NOTE: this may return negative values indicating | |
623 | a temporary error. We simply treat this as a | |
624 | match for now to avoid losing information that | |
625 | may be wanted. An error message will also be | |
626 | logged upon error */ | |
627 | if (f->lsm_rule) { | |
628 | if (need_sid) { | |
629 | security_task_getsecid(tsk, &sid); | |
630 | need_sid = 0; | |
631 | } | |
632 | result = security_audit_rule_match(sid, f->type, | |
633 | f->op, | |
634 | f->lsm_rule, | |
635 | ctx); | |
636 | } | |
637 | break; | |
638 | case AUDIT_OBJ_USER: | |
639 | case AUDIT_OBJ_ROLE: | |
640 | case AUDIT_OBJ_TYPE: | |
641 | case AUDIT_OBJ_LEV_LOW: | |
642 | case AUDIT_OBJ_LEV_HIGH: | |
643 | /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR | |
644 | also applies here */ | |
645 | if (f->lsm_rule) { | |
646 | /* Find files that match */ | |
647 | if (name) { | |
648 | result = security_audit_rule_match( | |
649 | name->osid, f->type, f->op, | |
650 | f->lsm_rule, ctx); | |
651 | } else if (ctx) { | |
652 | list_for_each_entry(n, &ctx->names_list, list) { | |
653 | if (security_audit_rule_match(n->osid, f->type, | |
654 | f->op, f->lsm_rule, | |
655 | ctx)) { | |
656 | ++result; | |
657 | break; | |
658 | } | |
659 | } | |
660 | } | |
661 | /* Find ipc objects that match */ | |
662 | if (!ctx || ctx->type != AUDIT_IPC) | |
663 | break; | |
664 | if (security_audit_rule_match(ctx->ipc.osid, | |
665 | f->type, f->op, | |
666 | f->lsm_rule, ctx)) | |
667 | ++result; | |
668 | } | |
669 | break; | |
670 | case AUDIT_ARG0: | |
671 | case AUDIT_ARG1: | |
672 | case AUDIT_ARG2: | |
673 | case AUDIT_ARG3: | |
674 | if (ctx) | |
675 | result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); | |
676 | break; | |
677 | case AUDIT_FILTERKEY: | |
678 | /* ignore this field for filtering */ | |
679 | result = 1; | |
680 | break; | |
681 | case AUDIT_PERM: | |
682 | result = audit_match_perm(ctx, f->val); | |
683 | break; | |
684 | case AUDIT_FILETYPE: | |
685 | result = audit_match_filetype(ctx, f->val); | |
686 | break; | |
687 | case AUDIT_FIELD_COMPARE: | |
688 | result = audit_field_compare(tsk, cred, f, ctx, name); | |
689 | break; | |
690 | } | |
691 | if (!result) | |
692 | return 0; | |
693 | } | |
694 | ||
695 | if (ctx) { | |
696 | if (rule->prio <= ctx->prio) | |
697 | return 0; | |
698 | if (rule->filterkey) { | |
699 | kfree(ctx->filterkey); | |
700 | ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); | |
701 | } | |
702 | ctx->prio = rule->prio; | |
703 | } | |
704 | switch (rule->action) { | |
705 | case AUDIT_NEVER: | |
706 | *state = AUDIT_DISABLED; | |
707 | break; | |
708 | case AUDIT_ALWAYS: | |
709 | *state = AUDIT_RECORD_CONTEXT; | |
710 | break; | |
711 | } | |
712 | return 1; | |
713 | } | |
714 | ||
715 | /* At process creation time, we can determine if system-call auditing is | |
716 | * completely disabled for this task. Since we only have the task | |
717 | * structure at this point, we can only check uid and gid. | |
718 | */ | |
719 | static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) | |
720 | { | |
721 | struct audit_entry *e; | |
722 | enum audit_state state; | |
723 | ||
724 | rcu_read_lock(); | |
725 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { | |
726 | if (audit_filter_rules(tsk, &e->rule, NULL, NULL, | |
727 | &state, true)) { | |
728 | if (state == AUDIT_RECORD_CONTEXT) | |
729 | *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); | |
730 | rcu_read_unlock(); | |
731 | return state; | |
732 | } | |
733 | } | |
734 | rcu_read_unlock(); | |
735 | return AUDIT_BUILD_CONTEXT; | |
736 | } | |
737 | ||
738 | static int audit_in_mask(const struct audit_krule *rule, unsigned long val) | |
739 | { | |
740 | int word, bit; | |
741 | ||
742 | if (val > 0xffffffff) | |
743 | return false; | |
744 | ||
745 | word = AUDIT_WORD(val); | |
746 | if (word >= AUDIT_BITMASK_SIZE) | |
747 | return false; | |
748 | ||
749 | bit = AUDIT_BIT(val); | |
750 | ||
751 | return rule->mask[word] & bit; | |
752 | } | |
753 | ||
754 | /* At syscall entry and exit time, this filter is called if the | |
755 | * audit_state is not low enough that auditing cannot take place, but is | |
756 | * also not high enough that we already know we have to write an audit | |
757 | * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). | |
758 | */ | |
759 | static enum audit_state audit_filter_syscall(struct task_struct *tsk, | |
760 | struct audit_context *ctx, | |
761 | struct list_head *list) | |
762 | { | |
763 | struct audit_entry *e; | |
764 | enum audit_state state; | |
765 | ||
766 | if (auditd_test_task(tsk)) | |
767 | return AUDIT_DISABLED; | |
768 | ||
769 | rcu_read_lock(); | |
770 | if (!list_empty(list)) { | |
771 | list_for_each_entry_rcu(e, list, list) { | |
772 | if (audit_in_mask(&e->rule, ctx->major) && | |
773 | audit_filter_rules(tsk, &e->rule, ctx, NULL, | |
774 | &state, false)) { | |
775 | rcu_read_unlock(); | |
776 | ctx->current_state = state; | |
777 | return state; | |
778 | } | |
779 | } | |
780 | } | |
781 | rcu_read_unlock(); | |
782 | return AUDIT_BUILD_CONTEXT; | |
783 | } | |
784 | ||
785 | /* | |
786 | * Given an audit_name check the inode hash table to see if they match. | |
787 | * Called holding the rcu read lock to protect the use of audit_inode_hash | |
788 | */ | |
789 | static int audit_filter_inode_name(struct task_struct *tsk, | |
790 | struct audit_names *n, | |
791 | struct audit_context *ctx) { | |
792 | int h = audit_hash_ino((u32)n->ino); | |
793 | struct list_head *list = &audit_inode_hash[h]; | |
794 | struct audit_entry *e; | |
795 | enum audit_state state; | |
796 | ||
797 | if (list_empty(list)) | |
798 | return 0; | |
799 | ||
800 | list_for_each_entry_rcu(e, list, list) { | |
801 | if (audit_in_mask(&e->rule, ctx->major) && | |
802 | audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { | |
803 | ctx->current_state = state; | |
804 | return 1; | |
805 | } | |
806 | } | |
807 | ||
808 | return 0; | |
809 | } | |
810 | ||
811 | /* At syscall exit time, this filter is called if any audit_names have been | |
812 | * collected during syscall processing. We only check rules in sublists at hash | |
813 | * buckets applicable to the inode numbers in audit_names. | |
814 | * Regarding audit_state, same rules apply as for audit_filter_syscall(). | |
815 | */ | |
816 | void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) | |
817 | { | |
818 | struct audit_names *n; | |
819 | ||
820 | if (auditd_test_task(tsk)) | |
821 | return; | |
822 | ||
823 | rcu_read_lock(); | |
824 | ||
825 | list_for_each_entry(n, &ctx->names_list, list) { | |
826 | if (audit_filter_inode_name(tsk, n, ctx)) | |
827 | break; | |
828 | } | |
829 | rcu_read_unlock(); | |
830 | } | |
831 | ||
832 | /* Transfer the audit context pointer to the caller, clearing it in the tsk's struct */ | |
833 | static inline struct audit_context *audit_take_context(struct task_struct *tsk, | |
834 | int return_valid, | |
835 | long return_code) | |
836 | { | |
837 | struct audit_context *context = tsk->audit_context; | |
838 | ||
839 | if (!context) | |
840 | return NULL; | |
841 | context->return_valid = return_valid; | |
842 | ||
843 | /* | |
844 | * we need to fix up the return code in the audit logs if the actual | |
845 | * return codes are later going to be fixed up by the arch specific | |
846 | * signal handlers | |
847 | * | |
848 | * This is actually a test for: | |
849 | * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || | |
850 | * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) | |
851 | * | |
852 | * but is faster than a bunch of || | |
853 | */ | |
854 | if (unlikely(return_code <= -ERESTARTSYS) && | |
855 | (return_code >= -ERESTART_RESTARTBLOCK) && | |
856 | (return_code != -ENOIOCTLCMD)) | |
857 | context->return_code = -EINTR; | |
858 | else | |
859 | context->return_code = return_code; | |
860 | ||
861 | if (context->in_syscall && !context->dummy) { | |
862 | audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); | |
863 | audit_filter_inodes(tsk, context); | |
864 | } | |
865 | ||
866 | tsk->audit_context = NULL; | |
867 | return context; | |
868 | } | |
869 | ||
870 | static inline void audit_proctitle_free(struct audit_context *context) | |
871 | { | |
872 | kfree(context->proctitle.value); | |
873 | context->proctitle.value = NULL; | |
874 | context->proctitle.len = 0; | |
875 | } | |
876 | ||
877 | static inline void audit_free_names(struct audit_context *context) | |
878 | { | |
879 | struct audit_names *n, *next; | |
880 | ||
881 | list_for_each_entry_safe(n, next, &context->names_list, list) { | |
882 | list_del(&n->list); | |
883 | if (n->name) | |
884 | putname(n->name); | |
885 | if (n->should_free) | |
886 | kfree(n); | |
887 | } | |
888 | context->name_count = 0; | |
889 | path_put(&context->pwd); | |
890 | context->pwd.dentry = NULL; | |
891 | context->pwd.mnt = NULL; | |
892 | } | |
893 | ||
894 | static inline void audit_free_aux(struct audit_context *context) | |
895 | { | |
896 | struct audit_aux_data *aux; | |
897 | ||
898 | while ((aux = context->aux)) { | |
899 | context->aux = aux->next; | |
900 | kfree(aux); | |
901 | } | |
902 | while ((aux = context->aux_pids)) { | |
903 | context->aux_pids = aux->next; | |
904 | kfree(aux); | |
905 | } | |
906 | } | |
907 | ||
908 | static inline struct audit_context *audit_alloc_context(enum audit_state state) | |
909 | { | |
910 | struct audit_context *context; | |
911 | ||
912 | context = kzalloc(sizeof(*context), GFP_KERNEL); | |
913 | if (!context) | |
914 | return NULL; | |
915 | context->state = state; | |
916 | context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; | |
917 | INIT_LIST_HEAD(&context->killed_trees); | |
918 | INIT_LIST_HEAD(&context->names_list); | |
919 | return context; | |
920 | } | |
921 | ||
922 | /** | |
923 | * audit_alloc - allocate an audit context block for a task | |
924 | * @tsk: task | |
925 | * | |
926 | * Filter on the task information and allocate a per-task audit context | |
927 | * if necessary. Doing so turns on system call auditing for the | |
928 | * specified task. This is called from copy_process, so no lock is | |
929 | * needed. | |
930 | */ | |
931 | int audit_alloc(struct task_struct *tsk) | |
932 | { | |
933 | struct audit_context *context; | |
934 | enum audit_state state; | |
935 | char *key = NULL; | |
936 | ||
937 | if (likely(!audit_ever_enabled)) | |
938 | return 0; /* Return if not auditing. */ | |
939 | ||
940 | state = audit_filter_task(tsk, &key); | |
941 | if (state == AUDIT_DISABLED) { | |
942 | clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); | |
943 | return 0; | |
944 | } | |
945 | ||
946 | if (!(context = audit_alloc_context(state))) { | |
947 | kfree(key); | |
948 | audit_log_lost("out of memory in audit_alloc"); | |
949 | return -ENOMEM; | |
950 | } | |
951 | context->filterkey = key; | |
952 | ||
953 | tsk->audit_context = context; | |
954 | set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); | |
955 | return 0; | |
956 | } | |
957 | ||
958 | static inline void audit_free_context(struct audit_context *context) | |
959 | { | |
960 | audit_free_names(context); | |
961 | unroll_tree_refs(context, NULL, 0); | |
962 | free_tree_refs(context); | |
963 | audit_free_aux(context); | |
964 | kfree(context->filterkey); | |
965 | kfree(context->sockaddr); | |
966 | audit_proctitle_free(context); | |
967 | kfree(context); | |
968 | } | |
969 | ||
970 | static int audit_log_pid_context(struct audit_context *context, pid_t pid, | |
971 | kuid_t auid, kuid_t uid, unsigned int sessionid, | |
972 | u32 sid, char *comm) | |
973 | { | |
974 | struct audit_buffer *ab; | |
975 | char *ctx = NULL; | |
976 | u32 len; | |
977 | int rc = 0; | |
978 | ||
979 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); | |
980 | if (!ab) | |
981 | return rc; | |
982 | ||
983 | audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, | |
984 | from_kuid(&init_user_ns, auid), | |
985 | from_kuid(&init_user_ns, uid), sessionid); | |
986 | if (sid) { | |
987 | if (security_secid_to_secctx(sid, &ctx, &len)) { | |
988 | audit_log_format(ab, " obj=(none)"); | |
989 | rc = 1; | |
990 | } else { | |
991 | audit_log_format(ab, " obj=%s", ctx); | |
992 | security_release_secctx(ctx, len); | |
993 | } | |
994 | } | |
995 | audit_log_format(ab, " ocomm="); | |
996 | audit_log_untrustedstring(ab, comm); | |
997 | audit_log_end(ab); | |
998 | ||
999 | return rc; | |
1000 | } | |
1001 | ||
1002 | static void audit_log_execve_info(struct audit_context *context, | |
1003 | struct audit_buffer **ab) | |
1004 | { | |
1005 | long len_max; | |
1006 | long len_rem; | |
1007 | long len_full; | |
1008 | long len_buf; | |
1009 | long len_abuf = 0; | |
1010 | long len_tmp; | |
1011 | bool require_data; | |
1012 | bool encode; | |
1013 | unsigned int iter; | |
1014 | unsigned int arg; | |
1015 | char *buf_head; | |
1016 | char *buf; | |
1017 | const char __user *p = (const char __user *)current->mm->arg_start; | |
1018 | ||
1019 | /* NOTE: this buffer needs to be large enough to hold all the non-arg | |
1020 | * data we put in the audit record for this argument (see the | |
1021 | * code below) ... at this point in time 96 is plenty */ | |
1022 | char abuf[96]; | |
1023 | ||
1024 | /* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the | |
1025 | * current value of 7500 is not as important as the fact that it | |
1026 | * is less than 8k, a setting of 7500 gives us plenty of wiggle | |
1027 | * room if we go over a little bit in the logging below */ | |
1028 | WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500); | |
1029 | len_max = MAX_EXECVE_AUDIT_LEN; | |
1030 | ||
1031 | /* scratch buffer to hold the userspace args */ | |
1032 | buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); | |
1033 | if (!buf_head) { | |
1034 | audit_panic("out of memory for argv string"); | |
1035 | return; | |
1036 | } | |
1037 | buf = buf_head; | |
1038 | ||
1039 | audit_log_format(*ab, "argc=%d", context->execve.argc); | |
1040 | ||
1041 | len_rem = len_max; | |
1042 | len_buf = 0; | |
1043 | len_full = 0; | |
1044 | require_data = true; | |
1045 | encode = false; | |
1046 | iter = 0; | |
1047 | arg = 0; | |
1048 | do { | |
1049 | /* NOTE: we don't ever want to trust this value for anything | |
1050 | * serious, but the audit record format insists we | |
1051 | * provide an argument length for really long arguments, | |
1052 | * e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but | |
1053 | * to use strncpy_from_user() to obtain this value for | |
1054 | * recording in the log, although we don't use it | |
1055 | * anywhere here to avoid a double-fetch problem */ | |
1056 | if (len_full == 0) | |
1057 | len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1; | |
1058 | ||
1059 | /* read more data from userspace */ | |
1060 | if (require_data) { | |
1061 | /* can we make more room in the buffer? */ | |
1062 | if (buf != buf_head) { | |
1063 | memmove(buf_head, buf, len_buf); | |
1064 | buf = buf_head; | |
1065 | } | |
1066 | ||
1067 | /* fetch as much as we can of the argument */ | |
1068 | len_tmp = strncpy_from_user(&buf_head[len_buf], p, | |
1069 | len_max - len_buf); | |
1070 | if (len_tmp == -EFAULT) { | |
1071 | /* unable to copy from userspace */ | |
1072 | send_sig(SIGKILL, current, 0); | |
1073 | goto out; | |
1074 | } else if (len_tmp == (len_max - len_buf)) { | |
1075 | /* buffer is not large enough */ | |
1076 | require_data = true; | |
1077 | /* NOTE: if we are going to span multiple | |
1078 | * buffers force the encoding so we stand | |
1079 | * a chance at a sane len_full value and | |
1080 | * consistent record encoding */ | |
1081 | encode = true; | |
1082 | len_full = len_full * 2; | |
1083 | p += len_tmp; | |
1084 | } else { | |
1085 | require_data = false; | |
1086 | if (!encode) | |
1087 | encode = audit_string_contains_control( | |
1088 | buf, len_tmp); | |
1089 | /* try to use a trusted value for len_full */ | |
1090 | if (len_full < len_max) | |
1091 | len_full = (encode ? | |
1092 | len_tmp * 2 : len_tmp); | |
1093 | p += len_tmp + 1; | |
1094 | } | |
1095 | len_buf += len_tmp; | |
1096 | buf_head[len_buf] = '\0'; | |
1097 | ||
1098 | /* length of the buffer in the audit record? */ | |
1099 | len_abuf = (encode ? len_buf * 2 : len_buf + 2); | |
1100 | } | |
1101 | ||
1102 | /* write as much as we can to the audit log */ | |
1103 | if (len_buf > 0) { | |
1104 | /* NOTE: some magic numbers here - basically if we | |
1105 | * can't fit a reasonable amount of data into the | |
1106 | * existing audit buffer, flush it and start with | |
1107 | * a new buffer */ | |
1108 | if ((sizeof(abuf) + 8) > len_rem) { | |
1109 | len_rem = len_max; | |
1110 | audit_log_end(*ab); | |
1111 | *ab = audit_log_start(context, | |
1112 | GFP_KERNEL, AUDIT_EXECVE); | |
1113 | if (!*ab) | |
1114 | goto out; | |
1115 | } | |
1116 | ||
1117 | /* create the non-arg portion of the arg record */ | |
1118 | len_tmp = 0; | |
1119 | if (require_data || (iter > 0) || | |
1120 | ((len_abuf + sizeof(abuf)) > len_rem)) { | |
1121 | if (iter == 0) { | |
1122 | len_tmp += snprintf(&abuf[len_tmp], | |
1123 | sizeof(abuf) - len_tmp, | |
1124 | " a%d_len=%lu", | |
1125 | arg, len_full); | |
1126 | } | |
1127 | len_tmp += snprintf(&abuf[len_tmp], | |
1128 | sizeof(abuf) - len_tmp, | |
1129 | " a%d[%d]=", arg, iter++); | |
1130 | } else | |
1131 | len_tmp += snprintf(&abuf[len_tmp], | |
1132 | sizeof(abuf) - len_tmp, | |
1133 | " a%d=", arg); | |
1134 | WARN_ON(len_tmp >= sizeof(abuf)); | |
1135 | abuf[sizeof(abuf) - 1] = '\0'; | |
1136 | ||
1137 | /* log the arg in the audit record */ | |
1138 | audit_log_format(*ab, "%s", abuf); | |
1139 | len_rem -= len_tmp; | |
1140 | len_tmp = len_buf; | |
1141 | if (encode) { | |
1142 | if (len_abuf > len_rem) | |
1143 | len_tmp = len_rem / 2; /* encoding */ | |
1144 | audit_log_n_hex(*ab, buf, len_tmp); | |
1145 | len_rem -= len_tmp * 2; | |
1146 | len_abuf -= len_tmp * 2; | |
1147 | } else { | |
1148 | if (len_abuf > len_rem) | |
1149 | len_tmp = len_rem - 2; /* quotes */ | |
1150 | audit_log_n_string(*ab, buf, len_tmp); | |
1151 | len_rem -= len_tmp + 2; | |
1152 | /* don't subtract the "2" because we still need | |
1153 | * to add quotes to the remaining string */ | |
1154 | len_abuf -= len_tmp; | |
1155 | } | |
1156 | len_buf -= len_tmp; | |
1157 | buf += len_tmp; | |
1158 | } | |
1159 | ||
1160 | /* ready to move to the next argument? */ | |
1161 | if ((len_buf == 0) && !require_data) { | |
1162 | arg++; | |
1163 | iter = 0; | |
1164 | len_full = 0; | |
1165 | require_data = true; | |
1166 | encode = false; | |
1167 | } | |
1168 | } while (arg < context->execve.argc); | |
1169 | ||
1170 | /* NOTE: the caller handles the final audit_log_end() call */ | |
1171 | ||
1172 | out: | |
1173 | kfree(buf_head); | |
1174 | } | |
1175 | ||
1176 | static void show_special(struct audit_context *context, int *call_panic) | |
1177 | { | |
1178 | struct audit_buffer *ab; | |
1179 | int i; | |
1180 | ||
1181 | ab = audit_log_start(context, GFP_KERNEL, context->type); | |
1182 | if (!ab) | |
1183 | return; | |
1184 | ||
1185 | switch (context->type) { | |
1186 | case AUDIT_SOCKETCALL: { | |
1187 | int nargs = context->socketcall.nargs; | |
1188 | audit_log_format(ab, "nargs=%d", nargs); | |
1189 | for (i = 0; i < nargs; i++) | |
1190 | audit_log_format(ab, " a%d=%lx", i, | |
1191 | context->socketcall.args[i]); | |
1192 | break; } | |
1193 | case AUDIT_IPC: { | |
1194 | u32 osid = context->ipc.osid; | |
1195 | ||
1196 | audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", | |
1197 | from_kuid(&init_user_ns, context->ipc.uid), | |
1198 | from_kgid(&init_user_ns, context->ipc.gid), | |
1199 | context->ipc.mode); | |
1200 | if (osid) { | |
1201 | char *ctx = NULL; | |
1202 | u32 len; | |
1203 | if (security_secid_to_secctx(osid, &ctx, &len)) { | |
1204 | audit_log_format(ab, " osid=%u", osid); | |
1205 | *call_panic = 1; | |
1206 | } else { | |
1207 | audit_log_format(ab, " obj=%s", ctx); | |
1208 | security_release_secctx(ctx, len); | |
1209 | } | |
1210 | } | |
1211 | if (context->ipc.has_perm) { | |
1212 | audit_log_end(ab); | |
1213 | ab = audit_log_start(context, GFP_KERNEL, | |
1214 | AUDIT_IPC_SET_PERM); | |
1215 | if (unlikely(!ab)) | |
1216 | return; | |
1217 | audit_log_format(ab, | |
1218 | "qbytes=%lx ouid=%u ogid=%u mode=%#ho", | |
1219 | context->ipc.qbytes, | |
1220 | context->ipc.perm_uid, | |
1221 | context->ipc.perm_gid, | |
1222 | context->ipc.perm_mode); | |
1223 | } | |
1224 | break; } | |
1225 | case AUDIT_MQ_OPEN: | |
1226 | audit_log_format(ab, | |
1227 | "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " | |
1228 | "mq_msgsize=%ld mq_curmsgs=%ld", | |
1229 | context->mq_open.oflag, context->mq_open.mode, | |
1230 | context->mq_open.attr.mq_flags, | |
1231 | context->mq_open.attr.mq_maxmsg, | |
1232 | context->mq_open.attr.mq_msgsize, | |
1233 | context->mq_open.attr.mq_curmsgs); | |
1234 | break; | |
1235 | case AUDIT_MQ_SENDRECV: | |
1236 | audit_log_format(ab, | |
1237 | "mqdes=%d msg_len=%zd msg_prio=%u " | |
1238 | "abs_timeout_sec=%lld abs_timeout_nsec=%ld", | |
1239 | context->mq_sendrecv.mqdes, | |
1240 | context->mq_sendrecv.msg_len, | |
1241 | context->mq_sendrecv.msg_prio, | |
1242 | (long long) context->mq_sendrecv.abs_timeout.tv_sec, | |
1243 | context->mq_sendrecv.abs_timeout.tv_nsec); | |
1244 | break; | |
1245 | case AUDIT_MQ_NOTIFY: | |
1246 | audit_log_format(ab, "mqdes=%d sigev_signo=%d", | |
1247 | context->mq_notify.mqdes, | |
1248 | context->mq_notify.sigev_signo); | |
1249 | break; | |
1250 | case AUDIT_MQ_GETSETATTR: { | |
1251 | struct mq_attr *attr = &context->mq_getsetattr.mqstat; | |
1252 | audit_log_format(ab, | |
1253 | "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " | |
1254 | "mq_curmsgs=%ld ", | |
1255 | context->mq_getsetattr.mqdes, | |
1256 | attr->mq_flags, attr->mq_maxmsg, | |
1257 | attr->mq_msgsize, attr->mq_curmsgs); | |
1258 | break; } | |
1259 | case AUDIT_CAPSET: | |
1260 | audit_log_format(ab, "pid=%d", context->capset.pid); | |
1261 | audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); | |
1262 | audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); | |
1263 | audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); | |
1264 | audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient); | |
1265 | break; | |
1266 | case AUDIT_MMAP: | |
1267 | audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, | |
1268 | context->mmap.flags); | |
1269 | break; | |
1270 | case AUDIT_EXECVE: | |
1271 | audit_log_execve_info(context, &ab); | |
1272 | break; | |
1273 | case AUDIT_KERN_MODULE: | |
1274 | audit_log_format(ab, "name="); | |
1275 | audit_log_untrustedstring(ab, context->module.name); | |
1276 | kfree(context->module.name); | |
1277 | break; | |
1278 | } | |
1279 | audit_log_end(ab); | |
1280 | } | |
1281 | ||
1282 | static inline int audit_proctitle_rtrim(char *proctitle, int len) | |
1283 | { | |
1284 | char *end = proctitle + len - 1; | |
1285 | while (end > proctitle && !isprint(*end)) | |
1286 | end--; | |
1287 | ||
1288 | /* catch the case where proctitle is only 1 non-print character */ | |
1289 | len = end - proctitle + 1; | |
1290 | len -= isprint(proctitle[len-1]) == 0; | |
1291 | return len; | |
1292 | } | |
1293 | ||
1294 | static void audit_log_proctitle(struct task_struct *tsk, | |
1295 | struct audit_context *context) | |
1296 | { | |
1297 | int res; | |
1298 | char *buf; | |
1299 | char *msg = "(null)"; | |
1300 | int len = strlen(msg); | |
1301 | struct audit_buffer *ab; | |
1302 | ||
1303 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE); | |
1304 | if (!ab) | |
1305 | return; /* audit_panic or being filtered */ | |
1306 | ||
1307 | audit_log_format(ab, "proctitle="); | |
1308 | ||
1309 | /* Not cached */ | |
1310 | if (!context->proctitle.value) { | |
1311 | buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL); | |
1312 | if (!buf) | |
1313 | goto out; | |
1314 | /* Historically called this from procfs naming */ | |
1315 | res = get_cmdline(tsk, buf, MAX_PROCTITLE_AUDIT_LEN); | |
1316 | if (res == 0) { | |
1317 | kfree(buf); | |
1318 | goto out; | |
1319 | } | |
1320 | res = audit_proctitle_rtrim(buf, res); | |
1321 | if (res == 0) { | |
1322 | kfree(buf); | |
1323 | goto out; | |
1324 | } | |
1325 | context->proctitle.value = buf; | |
1326 | context->proctitle.len = res; | |
1327 | } | |
1328 | msg = context->proctitle.value; | |
1329 | len = context->proctitle.len; | |
1330 | out: | |
1331 | audit_log_n_untrustedstring(ab, msg, len); | |
1332 | audit_log_end(ab); | |
1333 | } | |
1334 | ||
1335 | static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) | |
1336 | { | |
1337 | int i, call_panic = 0; | |
1338 | struct audit_buffer *ab; | |
1339 | struct audit_aux_data *aux; | |
1340 | struct audit_names *n; | |
1341 | ||
1342 | /* tsk == current */ | |
1343 | context->personality = tsk->personality; | |
1344 | ||
1345 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); | |
1346 | if (!ab) | |
1347 | return; /* audit_panic has been called */ | |
1348 | audit_log_format(ab, "arch=%x syscall=%d", | |
1349 | context->arch, context->major); | |
1350 | if (context->personality != PER_LINUX) | |
1351 | audit_log_format(ab, " per=%lx", context->personality); | |
1352 | if (context->return_valid) | |
1353 | audit_log_format(ab, " success=%s exit=%ld", | |
1354 | (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", | |
1355 | context->return_code); | |
1356 | ||
1357 | audit_log_format(ab, | |
1358 | " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", | |
1359 | context->argv[0], | |
1360 | context->argv[1], | |
1361 | context->argv[2], | |
1362 | context->argv[3], | |
1363 | context->name_count); | |
1364 | ||
1365 | audit_log_task_info(ab, tsk); | |
1366 | audit_log_key(ab, context->filterkey); | |
1367 | audit_log_end(ab); | |
1368 | ||
1369 | for (aux = context->aux; aux; aux = aux->next) { | |
1370 | ||
1371 | ab = audit_log_start(context, GFP_KERNEL, aux->type); | |
1372 | if (!ab) | |
1373 | continue; /* audit_panic has been called */ | |
1374 | ||
1375 | switch (aux->type) { | |
1376 | ||
1377 | case AUDIT_BPRM_FCAPS: { | |
1378 | struct audit_aux_data_bprm_fcaps *axs = (void *)aux; | |
1379 | audit_log_format(ab, "fver=%x", axs->fcap_ver); | |
1380 | audit_log_cap(ab, "fp", &axs->fcap.permitted); | |
1381 | audit_log_cap(ab, "fi", &axs->fcap.inheritable); | |
1382 | audit_log_format(ab, " fe=%d", axs->fcap.fE); | |
1383 | audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); | |
1384 | audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); | |
1385 | audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); | |
1386 | audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient); | |
1387 | audit_log_cap(ab, "pp", &axs->new_pcap.permitted); | |
1388 | audit_log_cap(ab, "pi", &axs->new_pcap.inheritable); | |
1389 | audit_log_cap(ab, "pe", &axs->new_pcap.effective); | |
1390 | audit_log_cap(ab, "pa", &axs->new_pcap.ambient); | |
1391 | break; } | |
1392 | ||
1393 | } | |
1394 | audit_log_end(ab); | |
1395 | } | |
1396 | ||
1397 | if (context->type) | |
1398 | show_special(context, &call_panic); | |
1399 | ||
1400 | if (context->fds[0] >= 0) { | |
1401 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); | |
1402 | if (ab) { | |
1403 | audit_log_format(ab, "fd0=%d fd1=%d", | |
1404 | context->fds[0], context->fds[1]); | |
1405 | audit_log_end(ab); | |
1406 | } | |
1407 | } | |
1408 | ||
1409 | if (context->sockaddr_len) { | |
1410 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); | |
1411 | if (ab) { | |
1412 | audit_log_format(ab, "saddr="); | |
1413 | audit_log_n_hex(ab, (void *)context->sockaddr, | |
1414 | context->sockaddr_len); | |
1415 | audit_log_end(ab); | |
1416 | } | |
1417 | } | |
1418 | ||
1419 | for (aux = context->aux_pids; aux; aux = aux->next) { | |
1420 | struct audit_aux_data_pids *axs = (void *)aux; | |
1421 | ||
1422 | for (i = 0; i < axs->pid_count; i++) | |
1423 | if (audit_log_pid_context(context, axs->target_pid[i], | |
1424 | axs->target_auid[i], | |
1425 | axs->target_uid[i], | |
1426 | axs->target_sessionid[i], | |
1427 | axs->target_sid[i], | |
1428 | axs->target_comm[i])) | |
1429 | call_panic = 1; | |
1430 | } | |
1431 | ||
1432 | if (context->target_pid && | |
1433 | audit_log_pid_context(context, context->target_pid, | |
1434 | context->target_auid, context->target_uid, | |
1435 | context->target_sessionid, | |
1436 | context->target_sid, context->target_comm)) | |
1437 | call_panic = 1; | |
1438 | ||
1439 | if (context->pwd.dentry && context->pwd.mnt) { | |
1440 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); | |
1441 | if (ab) { | |
1442 | audit_log_d_path(ab, "cwd=", &context->pwd); | |
1443 | audit_log_end(ab); | |
1444 | } | |
1445 | } | |
1446 | ||
1447 | i = 0; | |
1448 | list_for_each_entry(n, &context->names_list, list) { | |
1449 | if (n->hidden) | |
1450 | continue; | |
1451 | audit_log_name(context, n, NULL, i++, &call_panic); | |
1452 | } | |
1453 | ||
1454 | audit_log_proctitle(tsk, context); | |
1455 | ||
1456 | /* Send end of event record to help user space know we are finished */ | |
1457 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); | |
1458 | if (ab) | |
1459 | audit_log_end(ab); | |
1460 | if (call_panic) | |
1461 | audit_panic("error converting sid to string"); | |
1462 | } | |
1463 | ||
1464 | /** | |
1465 | * __audit_free - free a per-task audit context | |
1466 | * @tsk: task whose audit context block to free | |
1467 | * | |
1468 | * Called from copy_process and do_exit | |
1469 | */ | |
1470 | void __audit_free(struct task_struct *tsk) | |
1471 | { | |
1472 | struct audit_context *context; | |
1473 | ||
1474 | context = audit_take_context(tsk, 0, 0); | |
1475 | if (!context) | |
1476 | return; | |
1477 | ||
1478 | /* Check for system calls that do not go through the exit | |
1479 | * function (e.g., exit_group), then free context block. | |
1480 | * We use GFP_ATOMIC here because we might be doing this | |
1481 | * in the context of the idle thread */ | |
1482 | /* that can happen only if we are called from do_exit() */ | |
1483 | if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) | |
1484 | audit_log_exit(context, tsk); | |
1485 | if (!list_empty(&context->killed_trees)) | |
1486 | audit_kill_trees(&context->killed_trees); | |
1487 | ||
1488 | audit_free_context(context); | |
1489 | } | |
1490 | ||
1491 | /** | |
1492 | * __audit_syscall_entry - fill in an audit record at syscall entry | |
1493 | * @major: major syscall type (function) | |
1494 | * @a1: additional syscall register 1 | |
1495 | * @a2: additional syscall register 2 | |
1496 | * @a3: additional syscall register 3 | |
1497 | * @a4: additional syscall register 4 | |
1498 | * | |
1499 | * Fill in audit context at syscall entry. This only happens if the | |
1500 | * audit context was created when the task was created and the state or | |
1501 | * filters demand the audit context be built. If the state from the | |
1502 | * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, | |
1503 | * then the record will be written at syscall exit time (otherwise, it | |
1504 | * will only be written if another part of the kernel requests that it | |
1505 | * be written). | |
1506 | */ | |
1507 | void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2, | |
1508 | unsigned long a3, unsigned long a4) | |
1509 | { | |
1510 | struct task_struct *tsk = current; | |
1511 | struct audit_context *context = tsk->audit_context; | |
1512 | enum audit_state state; | |
1513 | ||
1514 | if (!context) | |
1515 | return; | |
1516 | ||
1517 | BUG_ON(context->in_syscall || context->name_count); | |
1518 | ||
1519 | if (!audit_enabled) | |
1520 | return; | |
1521 | ||
1522 | context->arch = syscall_get_arch(); | |
1523 | context->major = major; | |
1524 | context->argv[0] = a1; | |
1525 | context->argv[1] = a2; | |
1526 | context->argv[2] = a3; | |
1527 | context->argv[3] = a4; | |
1528 | ||
1529 | state = context->state; | |
1530 | context->dummy = !audit_n_rules; | |
1531 | if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { | |
1532 | context->prio = 0; | |
1533 | state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); | |
1534 | } | |
1535 | if (state == AUDIT_DISABLED) | |
1536 | return; | |
1537 | ||
1538 | context->serial = 0; | |
1539 | context->ctime = current_kernel_time64(); | |
1540 | context->in_syscall = 1; | |
1541 | context->current_state = state; | |
1542 | context->ppid = 0; | |
1543 | } | |
1544 | ||
1545 | /** | |
1546 | * __audit_syscall_exit - deallocate audit context after a system call | |
1547 | * @success: success value of the syscall | |
1548 | * @return_code: return value of the syscall | |
1549 | * | |
1550 | * Tear down after system call. If the audit context has been marked as | |
1551 | * auditable (either because of the AUDIT_RECORD_CONTEXT state from | |
1552 | * filtering, or because some other part of the kernel wrote an audit | |
1553 | * message), then write out the syscall information. In call cases, | |
1554 | * free the names stored from getname(). | |
1555 | */ | |
1556 | void __audit_syscall_exit(int success, long return_code) | |
1557 | { | |
1558 | struct task_struct *tsk = current; | |
1559 | struct audit_context *context; | |
1560 | ||
1561 | if (success) | |
1562 | success = AUDITSC_SUCCESS; | |
1563 | else | |
1564 | success = AUDITSC_FAILURE; | |
1565 | ||
1566 | context = audit_take_context(tsk, success, return_code); | |
1567 | if (!context) | |
1568 | return; | |
1569 | ||
1570 | if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) | |
1571 | audit_log_exit(context, tsk); | |
1572 | ||
1573 | context->in_syscall = 0; | |
1574 | context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; | |
1575 | ||
1576 | if (!list_empty(&context->killed_trees)) | |
1577 | audit_kill_trees(&context->killed_trees); | |
1578 | ||
1579 | audit_free_names(context); | |
1580 | unroll_tree_refs(context, NULL, 0); | |
1581 | audit_free_aux(context); | |
1582 | context->aux = NULL; | |
1583 | context->aux_pids = NULL; | |
1584 | context->target_pid = 0; | |
1585 | context->target_sid = 0; | |
1586 | context->sockaddr_len = 0; | |
1587 | context->type = 0; | |
1588 | context->fds[0] = -1; | |
1589 | if (context->state != AUDIT_RECORD_CONTEXT) { | |
1590 | kfree(context->filterkey); | |
1591 | context->filterkey = NULL; | |
1592 | } | |
1593 | tsk->audit_context = context; | |
1594 | } | |
1595 | ||
1596 | static inline void handle_one(const struct inode *inode) | |
1597 | { | |
1598 | #ifdef CONFIG_AUDIT_TREE | |
1599 | struct audit_context *context; | |
1600 | struct audit_tree_refs *p; | |
1601 | struct audit_chunk *chunk; | |
1602 | int count; | |
1603 | if (likely(!inode->i_fsnotify_marks)) | |
1604 | return; | |
1605 | context = current->audit_context; | |
1606 | p = context->trees; | |
1607 | count = context->tree_count; | |
1608 | rcu_read_lock(); | |
1609 | chunk = audit_tree_lookup(inode); | |
1610 | rcu_read_unlock(); | |
1611 | if (!chunk) | |
1612 | return; | |
1613 | if (likely(put_tree_ref(context, chunk))) | |
1614 | return; | |
1615 | if (unlikely(!grow_tree_refs(context))) { | |
1616 | pr_warn("out of memory, audit has lost a tree reference\n"); | |
1617 | audit_set_auditable(context); | |
1618 | audit_put_chunk(chunk); | |
1619 | unroll_tree_refs(context, p, count); | |
1620 | return; | |
1621 | } | |
1622 | put_tree_ref(context, chunk); | |
1623 | #endif | |
1624 | } | |
1625 | ||
1626 | static void handle_path(const struct dentry *dentry) | |
1627 | { | |
1628 | #ifdef CONFIG_AUDIT_TREE | |
1629 | struct audit_context *context; | |
1630 | struct audit_tree_refs *p; | |
1631 | const struct dentry *d, *parent; | |
1632 | struct audit_chunk *drop; | |
1633 | unsigned long seq; | |
1634 | int count; | |
1635 | ||
1636 | context = current->audit_context; | |
1637 | p = context->trees; | |
1638 | count = context->tree_count; | |
1639 | retry: | |
1640 | drop = NULL; | |
1641 | d = dentry; | |
1642 | rcu_read_lock(); | |
1643 | seq = read_seqbegin(&rename_lock); | |
1644 | for(;;) { | |
1645 | struct inode *inode = d_backing_inode(d); | |
1646 | if (inode && unlikely(inode->i_fsnotify_marks)) { | |
1647 | struct audit_chunk *chunk; | |
1648 | chunk = audit_tree_lookup(inode); | |
1649 | if (chunk) { | |
1650 | if (unlikely(!put_tree_ref(context, chunk))) { | |
1651 | drop = chunk; | |
1652 | break; | |
1653 | } | |
1654 | } | |
1655 | } | |
1656 | parent = d->d_parent; | |
1657 | if (parent == d) | |
1658 | break; | |
1659 | d = parent; | |
1660 | } | |
1661 | if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ | |
1662 | rcu_read_unlock(); | |
1663 | if (!drop) { | |
1664 | /* just a race with rename */ | |
1665 | unroll_tree_refs(context, p, count); | |
1666 | goto retry; | |
1667 | } | |
1668 | audit_put_chunk(drop); | |
1669 | if (grow_tree_refs(context)) { | |
1670 | /* OK, got more space */ | |
1671 | unroll_tree_refs(context, p, count); | |
1672 | goto retry; | |
1673 | } | |
1674 | /* too bad */ | |
1675 | pr_warn("out of memory, audit has lost a tree reference\n"); | |
1676 | unroll_tree_refs(context, p, count); | |
1677 | audit_set_auditable(context); | |
1678 | return; | |
1679 | } | |
1680 | rcu_read_unlock(); | |
1681 | #endif | |
1682 | } | |
1683 | ||
1684 | static struct audit_names *audit_alloc_name(struct audit_context *context, | |
1685 | unsigned char type) | |
1686 | { | |
1687 | struct audit_names *aname; | |
1688 | ||
1689 | if (context->name_count < AUDIT_NAMES) { | |
1690 | aname = &context->preallocated_names[context->name_count]; | |
1691 | memset(aname, 0, sizeof(*aname)); | |
1692 | } else { | |
1693 | aname = kzalloc(sizeof(*aname), GFP_NOFS); | |
1694 | if (!aname) | |
1695 | return NULL; | |
1696 | aname->should_free = true; | |
1697 | } | |
1698 | ||
1699 | aname->ino = AUDIT_INO_UNSET; | |
1700 | aname->type = type; | |
1701 | list_add_tail(&aname->list, &context->names_list); | |
1702 | ||
1703 | context->name_count++; | |
1704 | return aname; | |
1705 | } | |
1706 | ||
1707 | /** | |
1708 | * __audit_reusename - fill out filename with info from existing entry | |
1709 | * @uptr: userland ptr to pathname | |
1710 | * | |
1711 | * Search the audit_names list for the current audit context. If there is an | |
1712 | * existing entry with a matching "uptr" then return the filename | |
1713 | * associated with that audit_name. If not, return NULL. | |
1714 | */ | |
1715 | struct filename * | |
1716 | __audit_reusename(const __user char *uptr) | |
1717 | { | |
1718 | struct audit_context *context = current->audit_context; | |
1719 | struct audit_names *n; | |
1720 | ||
1721 | list_for_each_entry(n, &context->names_list, list) { | |
1722 | if (!n->name) | |
1723 | continue; | |
1724 | if (n->name->uptr == uptr) { | |
1725 | n->name->refcnt++; | |
1726 | return n->name; | |
1727 | } | |
1728 | } | |
1729 | return NULL; | |
1730 | } | |
1731 | ||
1732 | /** | |
1733 | * __audit_getname - add a name to the list | |
1734 | * @name: name to add | |
1735 | * | |
1736 | * Add a name to the list of audit names for this context. | |
1737 | * Called from fs/namei.c:getname(). | |
1738 | */ | |
1739 | void __audit_getname(struct filename *name) | |
1740 | { | |
1741 | struct audit_context *context = current->audit_context; | |
1742 | struct audit_names *n; | |
1743 | ||
1744 | if (!context->in_syscall) | |
1745 | return; | |
1746 | ||
1747 | n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); | |
1748 | if (!n) | |
1749 | return; | |
1750 | ||
1751 | n->name = name; | |
1752 | n->name_len = AUDIT_NAME_FULL; | |
1753 | name->aname = n; | |
1754 | name->refcnt++; | |
1755 | ||
1756 | if (!context->pwd.dentry) | |
1757 | get_fs_pwd(current->fs, &context->pwd); | |
1758 | } | |
1759 | ||
1760 | /** | |
1761 | * __audit_inode - store the inode and device from a lookup | |
1762 | * @name: name being audited | |
1763 | * @dentry: dentry being audited | |
1764 | * @flags: attributes for this particular entry | |
1765 | */ | |
1766 | void __audit_inode(struct filename *name, const struct dentry *dentry, | |
1767 | unsigned int flags) | |
1768 | { | |
1769 | struct audit_context *context = current->audit_context; | |
1770 | struct inode *inode = d_backing_inode(dentry); | |
1771 | struct audit_names *n; | |
1772 | bool parent = flags & AUDIT_INODE_PARENT; | |
1773 | ||
1774 | if (!context->in_syscall) | |
1775 | return; | |
1776 | ||
1777 | if (!name) | |
1778 | goto out_alloc; | |
1779 | ||
1780 | /* | |
1781 | * If we have a pointer to an audit_names entry already, then we can | |
1782 | * just use it directly if the type is correct. | |
1783 | */ | |
1784 | n = name->aname; | |
1785 | if (n) { | |
1786 | if (parent) { | |
1787 | if (n->type == AUDIT_TYPE_PARENT || | |
1788 | n->type == AUDIT_TYPE_UNKNOWN) | |
1789 | goto out; | |
1790 | } else { | |
1791 | if (n->type != AUDIT_TYPE_PARENT) | |
1792 | goto out; | |
1793 | } | |
1794 | } | |
1795 | ||
1796 | list_for_each_entry_reverse(n, &context->names_list, list) { | |
1797 | if (n->ino) { | |
1798 | /* valid inode number, use that for the comparison */ | |
1799 | if (n->ino != inode->i_ino || | |
1800 | n->dev != inode->i_sb->s_dev) | |
1801 | continue; | |
1802 | } else if (n->name) { | |
1803 | /* inode number has not been set, check the name */ | |
1804 | if (strcmp(n->name->name, name->name)) | |
1805 | continue; | |
1806 | } else | |
1807 | /* no inode and no name (?!) ... this is odd ... */ | |
1808 | continue; | |
1809 | ||
1810 | /* match the correct record type */ | |
1811 | if (parent) { | |
1812 | if (n->type == AUDIT_TYPE_PARENT || | |
1813 | n->type == AUDIT_TYPE_UNKNOWN) | |
1814 | goto out; | |
1815 | } else { | |
1816 | if (n->type != AUDIT_TYPE_PARENT) | |
1817 | goto out; | |
1818 | } | |
1819 | } | |
1820 | ||
1821 | out_alloc: | |
1822 | /* unable to find an entry with both a matching name and type */ | |
1823 | n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); | |
1824 | if (!n) | |
1825 | return; | |
1826 | if (name) { | |
1827 | n->name = name; | |
1828 | name->refcnt++; | |
1829 | } | |
1830 | ||
1831 | out: | |
1832 | if (parent) { | |
1833 | n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; | |
1834 | n->type = AUDIT_TYPE_PARENT; | |
1835 | if (flags & AUDIT_INODE_HIDDEN) | |
1836 | n->hidden = true; | |
1837 | } else { | |
1838 | n->name_len = AUDIT_NAME_FULL; | |
1839 | n->type = AUDIT_TYPE_NORMAL; | |
1840 | } | |
1841 | handle_path(dentry); | |
1842 | audit_copy_inode(n, dentry, inode); | |
1843 | } | |
1844 | ||
1845 | void __audit_file(const struct file *file) | |
1846 | { | |
1847 | __audit_inode(NULL, file->f_path.dentry, 0); | |
1848 | } | |
1849 | ||
1850 | /** | |
1851 | * __audit_inode_child - collect inode info for created/removed objects | |
1852 | * @parent: inode of dentry parent | |
1853 | * @dentry: dentry being audited | |
1854 | * @type: AUDIT_TYPE_* value that we're looking for | |
1855 | * | |
1856 | * For syscalls that create or remove filesystem objects, audit_inode | |
1857 | * can only collect information for the filesystem object's parent. | |
1858 | * This call updates the audit context with the child's information. | |
1859 | * Syscalls that create a new filesystem object must be hooked after | |
1860 | * the object is created. Syscalls that remove a filesystem object | |
1861 | * must be hooked prior, in order to capture the target inode during | |
1862 | * unsuccessful attempts. | |
1863 | */ | |
1864 | void __audit_inode_child(struct inode *parent, | |
1865 | const struct dentry *dentry, | |
1866 | const unsigned char type) | |
1867 | { | |
1868 | struct audit_context *context = current->audit_context; | |
1869 | struct inode *inode = d_backing_inode(dentry); | |
1870 | const char *dname = dentry->d_name.name; | |
1871 | struct audit_names *n, *found_parent = NULL, *found_child = NULL; | |
1872 | struct audit_entry *e; | |
1873 | struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; | |
1874 | int i; | |
1875 | ||
1876 | if (!context->in_syscall) | |
1877 | return; | |
1878 | ||
1879 | rcu_read_lock(); | |
1880 | if (!list_empty(list)) { | |
1881 | list_for_each_entry_rcu(e, list, list) { | |
1882 | for (i = 0; i < e->rule.field_count; i++) { | |
1883 | struct audit_field *f = &e->rule.fields[i]; | |
1884 | ||
1885 | if (f->type == AUDIT_FSTYPE) { | |
1886 | if (audit_comparator(parent->i_sb->s_magic, | |
1887 | f->op, f->val)) { | |
1888 | if (e->rule.action == AUDIT_NEVER) { | |
1889 | rcu_read_unlock(); | |
1890 | return; | |
1891 | } | |
1892 | } | |
1893 | } | |
1894 | } | |
1895 | } | |
1896 | } | |
1897 | rcu_read_unlock(); | |
1898 | ||
1899 | if (inode) | |
1900 | handle_one(inode); | |
1901 | ||
1902 | /* look for a parent entry first */ | |
1903 | list_for_each_entry(n, &context->names_list, list) { | |
1904 | if (!n->name || | |
1905 | (n->type != AUDIT_TYPE_PARENT && | |
1906 | n->type != AUDIT_TYPE_UNKNOWN)) | |
1907 | continue; | |
1908 | ||
1909 | if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev && | |
1910 | !audit_compare_dname_path(dname, | |
1911 | n->name->name, n->name_len)) { | |
1912 | if (n->type == AUDIT_TYPE_UNKNOWN) | |
1913 | n->type = AUDIT_TYPE_PARENT; | |
1914 | found_parent = n; | |
1915 | break; | |
1916 | } | |
1917 | } | |
1918 | ||
1919 | /* is there a matching child entry? */ | |
1920 | list_for_each_entry(n, &context->names_list, list) { | |
1921 | /* can only match entries that have a name */ | |
1922 | if (!n->name || | |
1923 | (n->type != type && n->type != AUDIT_TYPE_UNKNOWN)) | |
1924 | continue; | |
1925 | ||
1926 | if (!strcmp(dname, n->name->name) || | |
1927 | !audit_compare_dname_path(dname, n->name->name, | |
1928 | found_parent ? | |
1929 | found_parent->name_len : | |
1930 | AUDIT_NAME_FULL)) { | |
1931 | if (n->type == AUDIT_TYPE_UNKNOWN) | |
1932 | n->type = type; | |
1933 | found_child = n; | |
1934 | break; | |
1935 | } | |
1936 | } | |
1937 | ||
1938 | if (!found_parent) { | |
1939 | /* create a new, "anonymous" parent record */ | |
1940 | n = audit_alloc_name(context, AUDIT_TYPE_PARENT); | |
1941 | if (!n) | |
1942 | return; | |
1943 | audit_copy_inode(n, NULL, parent); | |
1944 | } | |
1945 | ||
1946 | if (!found_child) { | |
1947 | found_child = audit_alloc_name(context, type); | |
1948 | if (!found_child) | |
1949 | return; | |
1950 | ||
1951 | /* Re-use the name belonging to the slot for a matching parent | |
1952 | * directory. All names for this context are relinquished in | |
1953 | * audit_free_names() */ | |
1954 | if (found_parent) { | |
1955 | found_child->name = found_parent->name; | |
1956 | found_child->name_len = AUDIT_NAME_FULL; | |
1957 | found_child->name->refcnt++; | |
1958 | } | |
1959 | } | |
1960 | ||
1961 | if (inode) | |
1962 | audit_copy_inode(found_child, dentry, inode); | |
1963 | else | |
1964 | found_child->ino = AUDIT_INO_UNSET; | |
1965 | } | |
1966 | EXPORT_SYMBOL_GPL(__audit_inode_child); | |
1967 | ||
1968 | /** | |
1969 | * auditsc_get_stamp - get local copies of audit_context values | |
1970 | * @ctx: audit_context for the task | |
1971 | * @t: timespec64 to store time recorded in the audit_context | |
1972 | * @serial: serial value that is recorded in the audit_context | |
1973 | * | |
1974 | * Also sets the context as auditable. | |
1975 | */ | |
1976 | int auditsc_get_stamp(struct audit_context *ctx, | |
1977 | struct timespec64 *t, unsigned int *serial) | |
1978 | { | |
1979 | if (!ctx->in_syscall) | |
1980 | return 0; | |
1981 | if (!ctx->serial) | |
1982 | ctx->serial = audit_serial(); | |
1983 | t->tv_sec = ctx->ctime.tv_sec; | |
1984 | t->tv_nsec = ctx->ctime.tv_nsec; | |
1985 | *serial = ctx->serial; | |
1986 | if (!ctx->prio) { | |
1987 | ctx->prio = 1; | |
1988 | ctx->current_state = AUDIT_RECORD_CONTEXT; | |
1989 | } | |
1990 | return 1; | |
1991 | } | |
1992 | ||
1993 | /* global counter which is incremented every time something logs in */ | |
1994 | static atomic_t session_id = ATOMIC_INIT(0); | |
1995 | ||
1996 | static int audit_set_loginuid_perm(kuid_t loginuid) | |
1997 | { | |
1998 | /* if we are unset, we don't need privs */ | |
1999 | if (!audit_loginuid_set(current)) | |
2000 | return 0; | |
2001 | /* if AUDIT_FEATURE_LOGINUID_IMMUTABLE means never ever allow a change*/ | |
2002 | if (is_audit_feature_set(AUDIT_FEATURE_LOGINUID_IMMUTABLE)) | |
2003 | return -EPERM; | |
2004 | /* it is set, you need permission */ | |
2005 | if (!capable(CAP_AUDIT_CONTROL)) | |
2006 | return -EPERM; | |
2007 | /* reject if this is not an unset and we don't allow that */ | |
2008 | if (is_audit_feature_set(AUDIT_FEATURE_ONLY_UNSET_LOGINUID) && uid_valid(loginuid)) | |
2009 | return -EPERM; | |
2010 | return 0; | |
2011 | } | |
2012 | ||
2013 | static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid, | |
2014 | unsigned int oldsessionid, unsigned int sessionid, | |
2015 | int rc) | |
2016 | { | |
2017 | struct audit_buffer *ab; | |
2018 | uid_t uid, oldloginuid, loginuid; | |
2019 | struct tty_struct *tty; | |
2020 | ||
2021 | if (!audit_enabled) | |
2022 | return; | |
2023 | ||
2024 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); | |
2025 | if (!ab) | |
2026 | return; | |
2027 | ||
2028 | uid = from_kuid(&init_user_ns, task_uid(current)); | |
2029 | oldloginuid = from_kuid(&init_user_ns, koldloginuid); | |
2030 | loginuid = from_kuid(&init_user_ns, kloginuid), | |
2031 | tty = audit_get_tty(current); | |
2032 | ||
2033 | audit_log_format(ab, "pid=%d uid=%u", task_tgid_nr(current), uid); | |
2034 | audit_log_task_context(ab); | |
2035 | audit_log_format(ab, " old-auid=%u auid=%u tty=%s old-ses=%u ses=%u res=%d", | |
2036 | oldloginuid, loginuid, tty ? tty_name(tty) : "(none)", | |
2037 | oldsessionid, sessionid, !rc); | |
2038 | audit_put_tty(tty); | |
2039 | audit_log_end(ab); | |
2040 | } | |
2041 | ||
2042 | /** | |
2043 | * audit_set_loginuid - set current task's audit_context loginuid | |
2044 | * @loginuid: loginuid value | |
2045 | * | |
2046 | * Returns 0. | |
2047 | * | |
2048 | * Called (set) from fs/proc/base.c::proc_loginuid_write(). | |
2049 | */ | |
2050 | int audit_set_loginuid(kuid_t loginuid) | |
2051 | { | |
2052 | struct task_struct *task = current; | |
2053 | unsigned int oldsessionid, sessionid = (unsigned int)-1; | |
2054 | kuid_t oldloginuid; | |
2055 | int rc; | |
2056 | ||
2057 | oldloginuid = audit_get_loginuid(current); | |
2058 | oldsessionid = audit_get_sessionid(current); | |
2059 | ||
2060 | rc = audit_set_loginuid_perm(loginuid); | |
2061 | if (rc) | |
2062 | goto out; | |
2063 | ||
2064 | /* are we setting or clearing? */ | |
2065 | if (uid_valid(loginuid)) { | |
2066 | sessionid = (unsigned int)atomic_inc_return(&session_id); | |
2067 | if (unlikely(sessionid == (unsigned int)-1)) | |
2068 | sessionid = (unsigned int)atomic_inc_return(&session_id); | |
2069 | } | |
2070 | ||
2071 | task->sessionid = sessionid; | |
2072 | task->loginuid = loginuid; | |
2073 | out: | |
2074 | audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc); | |
2075 | return rc; | |
2076 | } | |
2077 | ||
2078 | /** | |
2079 | * __audit_mq_open - record audit data for a POSIX MQ open | |
2080 | * @oflag: open flag | |
2081 | * @mode: mode bits | |
2082 | * @attr: queue attributes | |
2083 | * | |
2084 | */ | |
2085 | void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) | |
2086 | { | |
2087 | struct audit_context *context = current->audit_context; | |
2088 | ||
2089 | if (attr) | |
2090 | memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); | |
2091 | else | |
2092 | memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); | |
2093 | ||
2094 | context->mq_open.oflag = oflag; | |
2095 | context->mq_open.mode = mode; | |
2096 | ||
2097 | context->type = AUDIT_MQ_OPEN; | |
2098 | } | |
2099 | ||
2100 | /** | |
2101 | * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive | |
2102 | * @mqdes: MQ descriptor | |
2103 | * @msg_len: Message length | |
2104 | * @msg_prio: Message priority | |
2105 | * @abs_timeout: Message timeout in absolute time | |
2106 | * | |
2107 | */ | |
2108 | void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, | |
2109 | const struct timespec64 *abs_timeout) | |
2110 | { | |
2111 | struct audit_context *context = current->audit_context; | |
2112 | struct timespec64 *p = &context->mq_sendrecv.abs_timeout; | |
2113 | ||
2114 | if (abs_timeout) | |
2115 | memcpy(p, abs_timeout, sizeof(*p)); | |
2116 | else | |
2117 | memset(p, 0, sizeof(*p)); | |
2118 | ||
2119 | context->mq_sendrecv.mqdes = mqdes; | |
2120 | context->mq_sendrecv.msg_len = msg_len; | |
2121 | context->mq_sendrecv.msg_prio = msg_prio; | |
2122 | ||
2123 | context->type = AUDIT_MQ_SENDRECV; | |
2124 | } | |
2125 | ||
2126 | /** | |
2127 | * __audit_mq_notify - record audit data for a POSIX MQ notify | |
2128 | * @mqdes: MQ descriptor | |
2129 | * @notification: Notification event | |
2130 | * | |
2131 | */ | |
2132 | ||
2133 | void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) | |
2134 | { | |
2135 | struct audit_context *context = current->audit_context; | |
2136 | ||
2137 | if (notification) | |
2138 | context->mq_notify.sigev_signo = notification->sigev_signo; | |
2139 | else | |
2140 | context->mq_notify.sigev_signo = 0; | |
2141 | ||
2142 | context->mq_notify.mqdes = mqdes; | |
2143 | context->type = AUDIT_MQ_NOTIFY; | |
2144 | } | |
2145 | ||
2146 | /** | |
2147 | * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute | |
2148 | * @mqdes: MQ descriptor | |
2149 | * @mqstat: MQ flags | |
2150 | * | |
2151 | */ | |
2152 | void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) | |
2153 | { | |
2154 | struct audit_context *context = current->audit_context; | |
2155 | context->mq_getsetattr.mqdes = mqdes; | |
2156 | context->mq_getsetattr.mqstat = *mqstat; | |
2157 | context->type = AUDIT_MQ_GETSETATTR; | |
2158 | } | |
2159 | ||
2160 | /** | |
2161 | * __audit_ipc_obj - record audit data for ipc object | |
2162 | * @ipcp: ipc permissions | |
2163 | * | |
2164 | */ | |
2165 | void __audit_ipc_obj(struct kern_ipc_perm *ipcp) | |
2166 | { | |
2167 | struct audit_context *context = current->audit_context; | |
2168 | context->ipc.uid = ipcp->uid; | |
2169 | context->ipc.gid = ipcp->gid; | |
2170 | context->ipc.mode = ipcp->mode; | |
2171 | context->ipc.has_perm = 0; | |
2172 | security_ipc_getsecid(ipcp, &context->ipc.osid); | |
2173 | context->type = AUDIT_IPC; | |
2174 | } | |
2175 | ||
2176 | /** | |
2177 | * __audit_ipc_set_perm - record audit data for new ipc permissions | |
2178 | * @qbytes: msgq bytes | |
2179 | * @uid: msgq user id | |
2180 | * @gid: msgq group id | |
2181 | * @mode: msgq mode (permissions) | |
2182 | * | |
2183 | * Called only after audit_ipc_obj(). | |
2184 | */ | |
2185 | void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) | |
2186 | { | |
2187 | struct audit_context *context = current->audit_context; | |
2188 | ||
2189 | context->ipc.qbytes = qbytes; | |
2190 | context->ipc.perm_uid = uid; | |
2191 | context->ipc.perm_gid = gid; | |
2192 | context->ipc.perm_mode = mode; | |
2193 | context->ipc.has_perm = 1; | |
2194 | } | |
2195 | ||
2196 | void __audit_bprm(struct linux_binprm *bprm) | |
2197 | { | |
2198 | struct audit_context *context = current->audit_context; | |
2199 | ||
2200 | context->type = AUDIT_EXECVE; | |
2201 | context->execve.argc = bprm->argc; | |
2202 | } | |
2203 | ||
2204 | ||
2205 | /** | |
2206 | * __audit_socketcall - record audit data for sys_socketcall | |
2207 | * @nargs: number of args, which should not be more than AUDITSC_ARGS. | |
2208 | * @args: args array | |
2209 | * | |
2210 | */ | |
2211 | int __audit_socketcall(int nargs, unsigned long *args) | |
2212 | { | |
2213 | struct audit_context *context = current->audit_context; | |
2214 | ||
2215 | if (nargs <= 0 || nargs > AUDITSC_ARGS || !args) | |
2216 | return -EINVAL; | |
2217 | context->type = AUDIT_SOCKETCALL; | |
2218 | context->socketcall.nargs = nargs; | |
2219 | memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); | |
2220 | return 0; | |
2221 | } | |
2222 | ||
2223 | /** | |
2224 | * __audit_fd_pair - record audit data for pipe and socketpair | |
2225 | * @fd1: the first file descriptor | |
2226 | * @fd2: the second file descriptor | |
2227 | * | |
2228 | */ | |
2229 | void __audit_fd_pair(int fd1, int fd2) | |
2230 | { | |
2231 | struct audit_context *context = current->audit_context; | |
2232 | context->fds[0] = fd1; | |
2233 | context->fds[1] = fd2; | |
2234 | } | |
2235 | ||
2236 | /** | |
2237 | * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto | |
2238 | * @len: data length in user space | |
2239 | * @a: data address in kernel space | |
2240 | * | |
2241 | * Returns 0 for success or NULL context or < 0 on error. | |
2242 | */ | |
2243 | int __audit_sockaddr(int len, void *a) | |
2244 | { | |
2245 | struct audit_context *context = current->audit_context; | |
2246 | ||
2247 | if (!context->sockaddr) { | |
2248 | void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); | |
2249 | if (!p) | |
2250 | return -ENOMEM; | |
2251 | context->sockaddr = p; | |
2252 | } | |
2253 | ||
2254 | context->sockaddr_len = len; | |
2255 | memcpy(context->sockaddr, a, len); | |
2256 | return 0; | |
2257 | } | |
2258 | ||
2259 | void __audit_ptrace(struct task_struct *t) | |
2260 | { | |
2261 | struct audit_context *context = current->audit_context; | |
2262 | ||
2263 | context->target_pid = task_tgid_nr(t); | |
2264 | context->target_auid = audit_get_loginuid(t); | |
2265 | context->target_uid = task_uid(t); | |
2266 | context->target_sessionid = audit_get_sessionid(t); | |
2267 | security_task_getsecid(t, &context->target_sid); | |
2268 | memcpy(context->target_comm, t->comm, TASK_COMM_LEN); | |
2269 | } | |
2270 | ||
2271 | /** | |
2272 | * audit_signal_info - record signal info for shutting down audit subsystem | |
2273 | * @sig: signal value | |
2274 | * @t: task being signaled | |
2275 | * | |
2276 | * If the audit subsystem is being terminated, record the task (pid) | |
2277 | * and uid that is doing that. | |
2278 | */ | |
2279 | int audit_signal_info(int sig, struct task_struct *t) | |
2280 | { | |
2281 | struct audit_aux_data_pids *axp; | |
2282 | struct task_struct *tsk = current; | |
2283 | struct audit_context *ctx = tsk->audit_context; | |
2284 | kuid_t uid = current_uid(), t_uid = task_uid(t); | |
2285 | ||
2286 | if (auditd_test_task(t) && | |
2287 | (sig == SIGTERM || sig == SIGHUP || | |
2288 | sig == SIGUSR1 || sig == SIGUSR2)) { | |
2289 | audit_sig_pid = task_tgid_nr(tsk); | |
2290 | if (uid_valid(tsk->loginuid)) | |
2291 | audit_sig_uid = tsk->loginuid; | |
2292 | else | |
2293 | audit_sig_uid = uid; | |
2294 | security_task_getsecid(tsk, &audit_sig_sid); | |
2295 | } | |
2296 | ||
2297 | if (!audit_signals || audit_dummy_context()) | |
2298 | return 0; | |
2299 | ||
2300 | /* optimize the common case by putting first signal recipient directly | |
2301 | * in audit_context */ | |
2302 | if (!ctx->target_pid) { | |
2303 | ctx->target_pid = task_tgid_nr(t); | |
2304 | ctx->target_auid = audit_get_loginuid(t); | |
2305 | ctx->target_uid = t_uid; | |
2306 | ctx->target_sessionid = audit_get_sessionid(t); | |
2307 | security_task_getsecid(t, &ctx->target_sid); | |
2308 | memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); | |
2309 | return 0; | |
2310 | } | |
2311 | ||
2312 | axp = (void *)ctx->aux_pids; | |
2313 | if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { | |
2314 | axp = kzalloc(sizeof(*axp), GFP_ATOMIC); | |
2315 | if (!axp) | |
2316 | return -ENOMEM; | |
2317 | ||
2318 | axp->d.type = AUDIT_OBJ_PID; | |
2319 | axp->d.next = ctx->aux_pids; | |
2320 | ctx->aux_pids = (void *)axp; | |
2321 | } | |
2322 | BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); | |
2323 | ||
2324 | axp->target_pid[axp->pid_count] = task_tgid_nr(t); | |
2325 | axp->target_auid[axp->pid_count] = audit_get_loginuid(t); | |
2326 | axp->target_uid[axp->pid_count] = t_uid; | |
2327 | axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); | |
2328 | security_task_getsecid(t, &axp->target_sid[axp->pid_count]); | |
2329 | memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); | |
2330 | axp->pid_count++; | |
2331 | ||
2332 | return 0; | |
2333 | } | |
2334 | ||
2335 | /** | |
2336 | * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps | |
2337 | * @bprm: pointer to the bprm being processed | |
2338 | * @new: the proposed new credentials | |
2339 | * @old: the old credentials | |
2340 | * | |
2341 | * Simply check if the proc already has the caps given by the file and if not | |
2342 | * store the priv escalation info for later auditing at the end of the syscall | |
2343 | * | |
2344 | * -Eric | |
2345 | */ | |
2346 | int __audit_log_bprm_fcaps(struct linux_binprm *bprm, | |
2347 | const struct cred *new, const struct cred *old) | |
2348 | { | |
2349 | struct audit_aux_data_bprm_fcaps *ax; | |
2350 | struct audit_context *context = current->audit_context; | |
2351 | struct cpu_vfs_cap_data vcaps; | |
2352 | ||
2353 | ax = kmalloc(sizeof(*ax), GFP_KERNEL); | |
2354 | if (!ax) | |
2355 | return -ENOMEM; | |
2356 | ||
2357 | ax->d.type = AUDIT_BPRM_FCAPS; | |
2358 | ax->d.next = context->aux; | |
2359 | context->aux = (void *)ax; | |
2360 | ||
2361 | get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps); | |
2362 | ||
2363 | ax->fcap.permitted = vcaps.permitted; | |
2364 | ax->fcap.inheritable = vcaps.inheritable; | |
2365 | ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); | |
2366 | ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; | |
2367 | ||
2368 | ax->old_pcap.permitted = old->cap_permitted; | |
2369 | ax->old_pcap.inheritable = old->cap_inheritable; | |
2370 | ax->old_pcap.effective = old->cap_effective; | |
2371 | ax->old_pcap.ambient = old->cap_ambient; | |
2372 | ||
2373 | ax->new_pcap.permitted = new->cap_permitted; | |
2374 | ax->new_pcap.inheritable = new->cap_inheritable; | |
2375 | ax->new_pcap.effective = new->cap_effective; | |
2376 | ax->new_pcap.ambient = new->cap_ambient; | |
2377 | return 0; | |
2378 | } | |
2379 | ||
2380 | /** | |
2381 | * __audit_log_capset - store information about the arguments to the capset syscall | |
2382 | * @new: the new credentials | |
2383 | * @old: the old (current) credentials | |
2384 | * | |
2385 | * Record the arguments userspace sent to sys_capset for later printing by the | |
2386 | * audit system if applicable | |
2387 | */ | |
2388 | void __audit_log_capset(const struct cred *new, const struct cred *old) | |
2389 | { | |
2390 | struct audit_context *context = current->audit_context; | |
2391 | context->capset.pid = task_tgid_nr(current); | |
2392 | context->capset.cap.effective = new->cap_effective; | |
2393 | context->capset.cap.inheritable = new->cap_effective; | |
2394 | context->capset.cap.permitted = new->cap_permitted; | |
2395 | context->capset.cap.ambient = new->cap_ambient; | |
2396 | context->type = AUDIT_CAPSET; | |
2397 | } | |
2398 | ||
2399 | void __audit_mmap_fd(int fd, int flags) | |
2400 | { | |
2401 | struct audit_context *context = current->audit_context; | |
2402 | context->mmap.fd = fd; | |
2403 | context->mmap.flags = flags; | |
2404 | context->type = AUDIT_MMAP; | |
2405 | } | |
2406 | ||
2407 | void __audit_log_kern_module(char *name) | |
2408 | { | |
2409 | struct audit_context *context = current->audit_context; | |
2410 | ||
2411 | context->module.name = kmalloc(strlen(name) + 1, GFP_KERNEL); | |
2412 | strcpy(context->module.name, name); | |
2413 | context->type = AUDIT_KERN_MODULE; | |
2414 | } | |
2415 | ||
2416 | void __audit_fanotify(unsigned int response) | |
2417 | { | |
2418 | audit_log(current->audit_context, GFP_KERNEL, | |
2419 | AUDIT_FANOTIFY, "resp=%u", response); | |
2420 | } | |
2421 | ||
2422 | static void audit_log_task(struct audit_buffer *ab) | |
2423 | { | |
2424 | kuid_t auid, uid; | |
2425 | kgid_t gid; | |
2426 | unsigned int sessionid; | |
2427 | char comm[sizeof(current->comm)]; | |
2428 | ||
2429 | auid = audit_get_loginuid(current); | |
2430 | sessionid = audit_get_sessionid(current); | |
2431 | current_uid_gid(&uid, &gid); | |
2432 | ||
2433 | audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", | |
2434 | from_kuid(&init_user_ns, auid), | |
2435 | from_kuid(&init_user_ns, uid), | |
2436 | from_kgid(&init_user_ns, gid), | |
2437 | sessionid); | |
2438 | audit_log_task_context(ab); | |
2439 | audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current)); | |
2440 | audit_log_untrustedstring(ab, get_task_comm(comm, current)); | |
2441 | audit_log_d_path_exe(ab, current->mm); | |
2442 | } | |
2443 | ||
2444 | /** | |
2445 | * audit_core_dumps - record information about processes that end abnormally | |
2446 | * @signr: signal value | |
2447 | * | |
2448 | * If a process ends with a core dump, something fishy is going on and we | |
2449 | * should record the event for investigation. | |
2450 | */ | |
2451 | void audit_core_dumps(long signr) | |
2452 | { | |
2453 | struct audit_buffer *ab; | |
2454 | ||
2455 | if (!audit_enabled) | |
2456 | return; | |
2457 | ||
2458 | if (signr == SIGQUIT) /* don't care for those */ | |
2459 | return; | |
2460 | ||
2461 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); | |
2462 | if (unlikely(!ab)) | |
2463 | return; | |
2464 | audit_log_task(ab); | |
2465 | audit_log_format(ab, " sig=%ld res=1", signr); | |
2466 | audit_log_end(ab); | |
2467 | } | |
2468 | ||
2469 | void __audit_seccomp(unsigned long syscall, long signr, int code) | |
2470 | { | |
2471 | struct audit_buffer *ab; | |
2472 | ||
2473 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP); | |
2474 | if (unlikely(!ab)) | |
2475 | return; | |
2476 | audit_log_task(ab); | |
2477 | audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x", | |
2478 | signr, syscall_get_arch(), syscall, | |
2479 | in_compat_syscall(), KSTK_EIP(current), code); | |
2480 | audit_log_end(ab); | |
2481 | } | |
2482 | ||
2483 | struct list_head *audit_killed_trees(void) | |
2484 | { | |
2485 | struct audit_context *ctx = current->audit_context; | |
2486 | if (likely(!ctx || !ctx->in_syscall)) | |
2487 | return NULL; | |
2488 | return &ctx->killed_trees; | |
2489 | } |