1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* auditsc.c -- System-call auditing support
3 * Handles all system-call specific auditing features.
4 *
5 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
6 * Copyright 2005 Hewlett-Packard Development Company, L.P.
7 * Copyright (C) 2005, 2006 IBM Corporation
8 * All Rights Reserved.
9 *
10 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
11 *
12 * Many of the ideas implemented here are from Stephen C. Tweedie,
13 * especially the idea of avoiding a copy by using getname.
14 *
15 * The method for actual interception of syscall entry and exit (not in
16 * this file -- see entry.S) is based on a GPL'd patch written by
17 * okir@suse.de and Copyright 2003 SuSE Linux AG.
18 *
19 * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
20 * 2006.
21 *
22 * The support of additional filter rules compares (>, <, >=, <=) was
23 * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
24 *
25 * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
26 * filesystem information.
27 *
28 * Subject and object context labeling support added by <danjones@us.ibm.com>
29 * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
30 */
31
32 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
33
34 #include <linux/init.h>
35 #include <asm/types.h>
36 #include <linux/atomic.h>
37 #include <linux/fs.h>
38 #include <linux/namei.h>
39 #include <linux/mm.h>
40 #include <linux/export.h>
41 #include <linux/slab.h>
42 #include <linux/mount.h>
43 #include <linux/socket.h>
44 #include <linux/mqueue.h>
45 #include <linux/audit.h>
46 #include <linux/personality.h>
47 #include <linux/time.h>
48 #include <linux/netlink.h>
49 #include <linux/compiler.h>
50 #include <asm/unistd.h>
51 #include <linux/security.h>
52 #include <linux/list.h>
53 #include <linux/binfmts.h>
54 #include <linux/highmem.h>
55 #include <linux/syscalls.h>
56 #include <asm/syscall.h>
57 #include <linux/capability.h>
58 #include <linux/fs_struct.h>
59 #include <linux/compat.h>
60 #include <linux/ctype.h>
61 #include <linux/string.h>
62 #include <linux/uaccess.h>
63 #include <linux/fsnotify_backend.h>
64 #include <uapi/linux/limits.h>
65 #include <uapi/linux/netfilter/nf_tables.h>
66 #include <uapi/linux/openat2.h> // struct open_how
67 #include <uapi/linux/fanotify.h>
68
69 #include "audit.h"
70
71 /* flags stating the success for a syscall */
72 #define AUDITSC_INVALID 0
73 #define AUDITSC_SUCCESS 1
74 #define AUDITSC_FAILURE 2
75
76 /* no execve audit message should be longer than this (userspace limits),
77 * see the note near the top of audit_log_execve_info() about this value */
78 #define MAX_EXECVE_AUDIT_LEN 7500
79
80 /* max length to print of cmdline/proctitle value during audit */
81 #define MAX_PROCTITLE_AUDIT_LEN 128
82
83 /* number of audit rules */
84 int audit_n_rules;
85
86 /* determines whether we collect data for signals sent */
87 int audit_signals;
88
89 struct audit_aux_data {
90 struct audit_aux_data *next;
91 int type;
92 };
93
94 /* Number of target pids per aux struct. */
95 #define AUDIT_AUX_PIDS 16
96
97 struct audit_aux_data_pids {
98 struct audit_aux_data d;
99 pid_t target_pid[AUDIT_AUX_PIDS];
100 kuid_t target_auid[AUDIT_AUX_PIDS];
101 kuid_t target_uid[AUDIT_AUX_PIDS];
102 unsigned int target_sessionid[AUDIT_AUX_PIDS];
103 struct lsm_prop target_ref[AUDIT_AUX_PIDS];
104 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
105 int pid_count;
106 };
107
108 struct audit_aux_data_bprm_fcaps {
109 struct audit_aux_data d;
110 struct audit_cap_data fcap;
111 unsigned int fcap_ver;
112 struct audit_cap_data old_pcap;
113 struct audit_cap_data new_pcap;
114 };
115
116 struct audit_tree_refs {
117 struct audit_tree_refs *next;
118 struct audit_chunk *c[31];
119 };
120
121 struct audit_nfcfgop_tab {
122 enum audit_nfcfgop op;
123 const char *s;
124 };
125
126 static const struct audit_nfcfgop_tab audit_nfcfgs[] = {
127 { AUDIT_XT_OP_REGISTER, "xt_register" },
128 { AUDIT_XT_OP_REPLACE, "xt_replace" },
129 { AUDIT_XT_OP_UNREGISTER, "xt_unregister" },
130 { AUDIT_NFT_OP_TABLE_REGISTER, "nft_register_table" },
131 { AUDIT_NFT_OP_TABLE_UNREGISTER, "nft_unregister_table" },
132 { AUDIT_NFT_OP_CHAIN_REGISTER, "nft_register_chain" },
133 { AUDIT_NFT_OP_CHAIN_UNREGISTER, "nft_unregister_chain" },
134 { AUDIT_NFT_OP_RULE_REGISTER, "nft_register_rule" },
135 { AUDIT_NFT_OP_RULE_UNREGISTER, "nft_unregister_rule" },
136 { AUDIT_NFT_OP_SET_REGISTER, "nft_register_set" },
137 { AUDIT_NFT_OP_SET_UNREGISTER, "nft_unregister_set" },
138 { AUDIT_NFT_OP_SETELEM_REGISTER, "nft_register_setelem" },
139 { AUDIT_NFT_OP_SETELEM_UNREGISTER, "nft_unregister_setelem" },
140 { AUDIT_NFT_OP_GEN_REGISTER, "nft_register_gen" },
141 { AUDIT_NFT_OP_OBJ_REGISTER, "nft_register_obj" },
142 { AUDIT_NFT_OP_OBJ_UNREGISTER, "nft_unregister_obj" },
143 { AUDIT_NFT_OP_OBJ_RESET, "nft_reset_obj" },
144 { AUDIT_NFT_OP_FLOWTABLE_REGISTER, "nft_register_flowtable" },
145 { AUDIT_NFT_OP_FLOWTABLE_UNREGISTER, "nft_unregister_flowtable" },
146 { AUDIT_NFT_OP_SETELEM_RESET, "nft_reset_setelem" },
147 { AUDIT_NFT_OP_RULE_RESET, "nft_reset_rule" },
148 { AUDIT_NFT_OP_INVALID, "nft_invalid" },
149 };
150
audit_match_perm(struct audit_context * ctx,int mask)151 static int audit_match_perm(struct audit_context *ctx, int mask)
152 {
153 unsigned n;
154
155 if (unlikely(!ctx))
156 return 0;
157 n = ctx->major;
158
159 switch (audit_classify_syscall(ctx->arch, n)) {
160 case AUDITSC_NATIVE:
161 if ((mask & AUDIT_PERM_WRITE) &&
162 audit_match_class(AUDIT_CLASS_WRITE, n))
163 return 1;
164 if ((mask & AUDIT_PERM_READ) &&
165 audit_match_class(AUDIT_CLASS_READ, n))
166 return 1;
167 if ((mask & AUDIT_PERM_ATTR) &&
168 audit_match_class(AUDIT_CLASS_CHATTR, n))
169 return 1;
170 return 0;
171 case AUDITSC_COMPAT: /* 32bit on biarch */
172 if ((mask & AUDIT_PERM_WRITE) &&
173 audit_match_class(AUDIT_CLASS_WRITE_32, n))
174 return 1;
175 if ((mask & AUDIT_PERM_READ) &&
176 audit_match_class(AUDIT_CLASS_READ_32, n))
177 return 1;
178 if ((mask & AUDIT_PERM_ATTR) &&
179 audit_match_class(AUDIT_CLASS_CHATTR_32, n))
180 return 1;
181 return 0;
182 case AUDITSC_OPEN:
183 return mask & ACC_MODE(ctx->argv[1]);
184 case AUDITSC_OPENAT:
185 return mask & ACC_MODE(ctx->argv[2]);
186 case AUDITSC_SOCKETCALL:
187 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
188 case AUDITSC_EXECVE:
189 return mask & AUDIT_PERM_EXEC;
190 case AUDITSC_OPENAT2:
191 return mask & ACC_MODE((u32)ctx->openat2.flags);
192 default:
193 return 0;
194 }
195 }
196
audit_match_filetype(struct audit_context * ctx,int val)197 static int audit_match_filetype(struct audit_context *ctx, int val)
198 {
199 struct audit_names *n;
200 umode_t mode = (umode_t)val;
201
202 if (unlikely(!ctx))
203 return 0;
204
205 list_for_each_entry(n, &ctx->names_list, list) {
206 if ((n->ino != AUDIT_INO_UNSET) &&
207 ((n->mode & S_IFMT) == mode))
208 return 1;
209 }
210
211 return 0;
212 }
213
214 /*
215 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
216 * ->first_trees points to its beginning, ->trees - to the current end of data.
217 * ->tree_count is the number of free entries in array pointed to by ->trees.
218 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
219 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously,
220 * it's going to remain 1-element for almost any setup) until we free context itself.
221 * References in it _are_ dropped - at the same time we free/drop aux stuff.
222 */
223
audit_set_auditable(struct audit_context * ctx)224 static void audit_set_auditable(struct audit_context *ctx)
225 {
226 if (!ctx->prio) {
227 ctx->prio = 1;
228 ctx->current_state = AUDIT_STATE_RECORD;
229 }
230 }
231
put_tree_ref(struct audit_context * ctx,struct audit_chunk * chunk)232 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
233 {
234 struct audit_tree_refs *p = ctx->trees;
235 int left = ctx->tree_count;
236
237 if (likely(left)) {
238 p->c[--left] = chunk;
239 ctx->tree_count = left;
240 return 1;
241 }
242 if (!p)
243 return 0;
244 p = p->next;
245 if (p) {
246 p->c[30] = chunk;
247 ctx->trees = p;
248 ctx->tree_count = 30;
249 return 1;
250 }
251 return 0;
252 }
253
grow_tree_refs(struct audit_context * ctx)254 static int grow_tree_refs(struct audit_context *ctx)
255 {
256 struct audit_tree_refs *p = ctx->trees;
257
258 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
259 if (!ctx->trees) {
260 ctx->trees = p;
261 return 0;
262 }
263 if (p)
264 p->next = ctx->trees;
265 else
266 ctx->first_trees = ctx->trees;
267 ctx->tree_count = 31;
268 return 1;
269 }
270
unroll_tree_refs(struct audit_context * ctx,struct audit_tree_refs * p,int count)271 static void unroll_tree_refs(struct audit_context *ctx,
272 struct audit_tree_refs *p, int count)
273 {
274 struct audit_tree_refs *q;
275 int n;
276
277 if (!p) {
278 /* we started with empty chain */
279 p = ctx->first_trees;
280 count = 31;
281 /* if the very first allocation has failed, nothing to do */
282 if (!p)
283 return;
284 }
285 n = count;
286 for (q = p; q != ctx->trees; q = q->next, n = 31) {
287 while (n--) {
288 audit_put_chunk(q->c[n]);
289 q->c[n] = NULL;
290 }
291 }
292 while (n-- > ctx->tree_count) {
293 audit_put_chunk(q->c[n]);
294 q->c[n] = NULL;
295 }
296 ctx->trees = p;
297 ctx->tree_count = count;
298 }
299
free_tree_refs(struct audit_context * ctx)300 static void free_tree_refs(struct audit_context *ctx)
301 {
302 struct audit_tree_refs *p, *q;
303
304 for (p = ctx->first_trees; p; p = q) {
305 q = p->next;
306 kfree(p);
307 }
308 }
309
match_tree_refs(struct audit_context * ctx,struct audit_tree * tree)310 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
311 {
312 struct audit_tree_refs *p;
313 int n;
314
315 if (!tree)
316 return 0;
317 /* full ones */
318 for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
319 for (n = 0; n < 31; n++)
320 if (audit_tree_match(p->c[n], tree))
321 return 1;
322 }
323 /* partial */
324 if (p) {
325 for (n = ctx->tree_count; n < 31; n++)
326 if (audit_tree_match(p->c[n], tree))
327 return 1;
328 }
329 return 0;
330 }
331
audit_compare_uid(kuid_t uid,struct audit_names * name,struct audit_field * f,struct audit_context * ctx)332 static int audit_compare_uid(kuid_t uid,
333 struct audit_names *name,
334 struct audit_field *f,
335 struct audit_context *ctx)
336 {
337 struct audit_names *n;
338 int rc;
339
340 if (name) {
341 rc = audit_uid_comparator(uid, f->op, name->uid);
342 if (rc)
343 return rc;
344 }
345
346 if (ctx) {
347 list_for_each_entry(n, &ctx->names_list, list) {
348 rc = audit_uid_comparator(uid, f->op, n->uid);
349 if (rc)
350 return rc;
351 }
352 }
353 return 0;
354 }
355
audit_compare_gid(kgid_t gid,struct audit_names * name,struct audit_field * f,struct audit_context * ctx)356 static int audit_compare_gid(kgid_t gid,
357 struct audit_names *name,
358 struct audit_field *f,
359 struct audit_context *ctx)
360 {
361 struct audit_names *n;
362 int rc;
363
364 if (name) {
365 rc = audit_gid_comparator(gid, f->op, name->gid);
366 if (rc)
367 return rc;
368 }
369
370 if (ctx) {
371 list_for_each_entry(n, &ctx->names_list, list) {
372 rc = audit_gid_comparator(gid, f->op, n->gid);
373 if (rc)
374 return rc;
375 }
376 }
377 return 0;
378 }
379
audit_field_compare(struct task_struct * tsk,const struct cred * cred,struct audit_field * f,struct audit_context * ctx,struct audit_names * name)380 static int audit_field_compare(struct task_struct *tsk,
381 const struct cred *cred,
382 struct audit_field *f,
383 struct audit_context *ctx,
384 struct audit_names *name)
385 {
386 switch (f->val) {
387 /* process to file object comparisons */
388 case AUDIT_COMPARE_UID_TO_OBJ_UID:
389 return audit_compare_uid(cred->uid, name, f, ctx);
390 case AUDIT_COMPARE_GID_TO_OBJ_GID:
391 return audit_compare_gid(cred->gid, name, f, ctx);
392 case AUDIT_COMPARE_EUID_TO_OBJ_UID:
393 return audit_compare_uid(cred->euid, name, f, ctx);
394 case AUDIT_COMPARE_EGID_TO_OBJ_GID:
395 return audit_compare_gid(cred->egid, name, f, ctx);
396 case AUDIT_COMPARE_AUID_TO_OBJ_UID:
397 return audit_compare_uid(audit_get_loginuid(tsk), name, f, ctx);
398 case AUDIT_COMPARE_SUID_TO_OBJ_UID:
399 return audit_compare_uid(cred->suid, name, f, ctx);
400 case AUDIT_COMPARE_SGID_TO_OBJ_GID:
401 return audit_compare_gid(cred->sgid, name, f, ctx);
402 case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
403 return audit_compare_uid(cred->fsuid, name, f, ctx);
404 case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
405 return audit_compare_gid(cred->fsgid, name, f, ctx);
406 /* uid comparisons */
407 case AUDIT_COMPARE_UID_TO_AUID:
408 return audit_uid_comparator(cred->uid, f->op,
409 audit_get_loginuid(tsk));
410 case AUDIT_COMPARE_UID_TO_EUID:
411 return audit_uid_comparator(cred->uid, f->op, cred->euid);
412 case AUDIT_COMPARE_UID_TO_SUID:
413 return audit_uid_comparator(cred->uid, f->op, cred->suid);
414 case AUDIT_COMPARE_UID_TO_FSUID:
415 return audit_uid_comparator(cred->uid, f->op, cred->fsuid);
416 /* auid comparisons */
417 case AUDIT_COMPARE_AUID_TO_EUID:
418 return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
419 cred->euid);
420 case AUDIT_COMPARE_AUID_TO_SUID:
421 return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
422 cred->suid);
423 case AUDIT_COMPARE_AUID_TO_FSUID:
424 return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
425 cred->fsuid);
426 /* euid comparisons */
427 case AUDIT_COMPARE_EUID_TO_SUID:
428 return audit_uid_comparator(cred->euid, f->op, cred->suid);
429 case AUDIT_COMPARE_EUID_TO_FSUID:
430 return audit_uid_comparator(cred->euid, f->op, cred->fsuid);
431 /* suid comparisons */
432 case AUDIT_COMPARE_SUID_TO_FSUID:
433 return audit_uid_comparator(cred->suid, f->op, cred->fsuid);
434 /* gid comparisons */
435 case AUDIT_COMPARE_GID_TO_EGID:
436 return audit_gid_comparator(cred->gid, f->op, cred->egid);
437 case AUDIT_COMPARE_GID_TO_SGID:
438 return audit_gid_comparator(cred->gid, f->op, cred->sgid);
439 case AUDIT_COMPARE_GID_TO_FSGID:
440 return audit_gid_comparator(cred->gid, f->op, cred->fsgid);
441 /* egid comparisons */
442 case AUDIT_COMPARE_EGID_TO_SGID:
443 return audit_gid_comparator(cred->egid, f->op, cred->sgid);
444 case AUDIT_COMPARE_EGID_TO_FSGID:
445 return audit_gid_comparator(cred->egid, f->op, cred->fsgid);
446 /* sgid comparison */
447 case AUDIT_COMPARE_SGID_TO_FSGID:
448 return audit_gid_comparator(cred->sgid, f->op, cred->fsgid);
449 default:
450 WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n");
451 return 0;
452 }
453 return 0;
454 }
455
456 /* Determine if any context name data matches a rule's watch data */
457 /* Compare a task_struct with an audit_rule. Return 1 on match, 0
458 * otherwise.
459 *
460 * If task_creation is true, this is an explicit indication that we are
461 * filtering a task rule at task creation time. This and tsk == current are
462 * the only situations where tsk->cred may be accessed without an rcu read lock.
463 */
audit_filter_rules(struct task_struct * tsk,struct audit_krule * rule,struct audit_context * ctx,struct audit_names * name,enum audit_state * state,bool task_creation)464 static int audit_filter_rules(struct task_struct *tsk,
465 struct audit_krule *rule,
466 struct audit_context *ctx,
467 struct audit_names *name,
468 enum audit_state *state,
469 bool task_creation)
470 {
471 const struct cred *cred;
472 int i, need_sid = 1;
473 struct lsm_prop prop = { };
474 unsigned int sessionid;
475
476 if (ctx && rule->prio <= ctx->prio)
477 return 0;
478
479 cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
480
481 for (i = 0; i < rule->field_count; i++) {
482 struct audit_field *f = &rule->fields[i];
483 struct audit_names *n;
484 int result = 0;
485 pid_t pid;
486
487 switch (f->type) {
488 case AUDIT_PID:
489 pid = task_tgid_nr(tsk);
490 result = audit_comparator(pid, f->op, f->val);
491 break;
492 case AUDIT_PPID:
493 if (ctx) {
494 if (!ctx->ppid)
495 ctx->ppid = task_ppid_nr(tsk);
496 result = audit_comparator(ctx->ppid, f->op, f->val);
497 }
498 break;
499 case AUDIT_EXE:
500 result = audit_exe_compare(tsk, rule->exe);
501 if (f->op == Audit_not_equal)
502 result = !result;
503 break;
504 case AUDIT_UID:
505 result = audit_uid_comparator(cred->uid, f->op, f->uid);
506 break;
507 case AUDIT_EUID:
508 result = audit_uid_comparator(cred->euid, f->op, f->uid);
509 break;
510 case AUDIT_SUID:
511 result = audit_uid_comparator(cred->suid, f->op, f->uid);
512 break;
513 case AUDIT_FSUID:
514 result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
515 break;
516 case AUDIT_GID:
517 result = audit_gid_comparator(cred->gid, f->op, f->gid);
518 if (f->op == Audit_equal) {
519 if (!result)
520 result = groups_search(cred->group_info, f->gid);
521 } else if (f->op == Audit_not_equal) {
522 if (result)
523 result = !groups_search(cred->group_info, f->gid);
524 }
525 break;
526 case AUDIT_EGID:
527 result = audit_gid_comparator(cred->egid, f->op, f->gid);
528 if (f->op == Audit_equal) {
529 if (!result)
530 result = groups_search(cred->group_info, f->gid);
531 } else if (f->op == Audit_not_equal) {
532 if (result)
533 result = !groups_search(cred->group_info, f->gid);
534 }
535 break;
536 case AUDIT_SGID:
537 result = audit_gid_comparator(cred->sgid, f->op, f->gid);
538 break;
539 case AUDIT_FSGID:
540 result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
541 break;
542 case AUDIT_SESSIONID:
543 sessionid = audit_get_sessionid(tsk);
544 result = audit_comparator(sessionid, f->op, f->val);
545 break;
546 case AUDIT_PERS:
547 result = audit_comparator(tsk->personality, f->op, f->val);
548 break;
549 case AUDIT_ARCH:
550 if (ctx)
551 result = audit_comparator(ctx->arch, f->op, f->val);
552 break;
553
554 case AUDIT_EXIT:
555 if (ctx && ctx->return_valid != AUDITSC_INVALID)
556 result = audit_comparator(ctx->return_code, f->op, f->val);
557 break;
558 case AUDIT_SUCCESS:
559 if (ctx && ctx->return_valid != AUDITSC_INVALID) {
560 if (f->val)
561 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
562 else
563 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
564 }
565 break;
566 case AUDIT_DEVMAJOR:
567 if (name) {
568 if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
569 audit_comparator(MAJOR(name->rdev), f->op, f->val))
570 ++result;
571 } else if (ctx) {
572 list_for_each_entry(n, &ctx->names_list, list) {
573 if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
574 audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
575 ++result;
576 break;
577 }
578 }
579 }
580 break;
581 case AUDIT_DEVMINOR:
582 if (name) {
583 if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
584 audit_comparator(MINOR(name->rdev), f->op, f->val))
585 ++result;
586 } else if (ctx) {
587 list_for_each_entry(n, &ctx->names_list, list) {
588 if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
589 audit_comparator(MINOR(n->rdev), f->op, f->val)) {
590 ++result;
591 break;
592 }
593 }
594 }
595 break;
596 case AUDIT_INODE:
597 if (name)
598 result = audit_comparator(name->ino, f->op, f->val);
599 else if (ctx) {
600 list_for_each_entry(n, &ctx->names_list, list) {
601 if (audit_comparator(n->ino, f->op, f->val)) {
602 ++result;
603 break;
604 }
605 }
606 }
607 break;
608 case AUDIT_OBJ_UID:
609 if (name) {
610 result = audit_uid_comparator(name->uid, f->op, f->uid);
611 } else if (ctx) {
612 list_for_each_entry(n, &ctx->names_list, list) {
613 if (audit_uid_comparator(n->uid, f->op, f->uid)) {
614 ++result;
615 break;
616 }
617 }
618 }
619 break;
620 case AUDIT_OBJ_GID:
621 if (name) {
622 result = audit_gid_comparator(name->gid, f->op, f->gid);
623 } else if (ctx) {
624 list_for_each_entry(n, &ctx->names_list, list) {
625 if (audit_gid_comparator(n->gid, f->op, f->gid)) {
626 ++result;
627 break;
628 }
629 }
630 }
631 break;
632 case AUDIT_WATCH:
633 if (name) {
634 result = audit_watch_compare(rule->watch,
635 name->ino,
636 name->dev);
637 if (f->op == Audit_not_equal)
638 result = !result;
639 }
640 break;
641 case AUDIT_DIR:
642 if (ctx) {
643 result = match_tree_refs(ctx, rule->tree);
644 if (f->op == Audit_not_equal)
645 result = !result;
646 }
647 break;
648 case AUDIT_LOGINUID:
649 result = audit_uid_comparator(audit_get_loginuid(tsk),
650 f->op, f->uid);
651 break;
652 case AUDIT_LOGINUID_SET:
653 result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val);
654 break;
655 case AUDIT_SADDR_FAM:
656 if (ctx && ctx->sockaddr)
657 result = audit_comparator(ctx->sockaddr->ss_family,
658 f->op, f->val);
659 break;
660 case AUDIT_SUBJ_USER:
661 case AUDIT_SUBJ_ROLE:
662 case AUDIT_SUBJ_TYPE:
663 case AUDIT_SUBJ_SEN:
664 case AUDIT_SUBJ_CLR:
665 /* NOTE: this may return negative values indicating
666 a temporary error. We simply treat this as a
667 match for now to avoid losing information that
668 may be wanted. An error message will also be
669 logged upon error */
670 if (f->lsm_rule) {
671 if (need_sid) {
672 /* @tsk should always be equal to
673 * @current with the exception of
674 * fork()/copy_process() in which case
675 * the new @tsk creds are still a dup
676 * of @current's creds so we can still
677 * use
678 * security_current_getlsmprop_subj()
679 * here even though it always refs
680 * @current's creds
681 */
682 security_current_getlsmprop_subj(&prop);
683 need_sid = 0;
684 }
685 result = security_audit_rule_match(&prop,
686 f->type,
687 f->op,
688 f->lsm_rule);
689 }
690 break;
691 case AUDIT_OBJ_USER:
692 case AUDIT_OBJ_ROLE:
693 case AUDIT_OBJ_TYPE:
694 case AUDIT_OBJ_LEV_LOW:
695 case AUDIT_OBJ_LEV_HIGH:
696 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
697 also applies here */
698 if (f->lsm_rule) {
699 /* Find files that match */
700 if (name) {
701 result = security_audit_rule_match(
702 &name->oprop,
703 f->type,
704 f->op,
705 f->lsm_rule);
706 } else if (ctx) {
707 list_for_each_entry(n, &ctx->names_list, list) {
708 if (security_audit_rule_match(
709 &n->oprop,
710 f->type,
711 f->op,
712 f->lsm_rule)) {
713 ++result;
714 break;
715 }
716 }
717 }
718 /* Find ipc objects that match */
719 if (!ctx || ctx->type != AUDIT_IPC)
720 break;
721 if (security_audit_rule_match(&ctx->ipc.oprop,
722 f->type, f->op,
723 f->lsm_rule))
724 ++result;
725 }
726 break;
727 case AUDIT_ARG0:
728 case AUDIT_ARG1:
729 case AUDIT_ARG2:
730 case AUDIT_ARG3:
731 if (ctx)
732 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
733 break;
734 case AUDIT_FILTERKEY:
735 /* ignore this field for filtering */
736 result = 1;
737 break;
738 case AUDIT_PERM:
739 result = audit_match_perm(ctx, f->val);
740 if (f->op == Audit_not_equal)
741 result = !result;
742 break;
743 case AUDIT_FILETYPE:
744 result = audit_match_filetype(ctx, f->val);
745 if (f->op == Audit_not_equal)
746 result = !result;
747 break;
748 case AUDIT_FIELD_COMPARE:
749 result = audit_field_compare(tsk, cred, f, ctx, name);
750 break;
751 }
752 if (!result)
753 return 0;
754 }
755
756 if (ctx) {
757 if (rule->filterkey) {
758 kfree(ctx->filterkey);
759 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
760 }
761 ctx->prio = rule->prio;
762 }
763 switch (rule->action) {
764 case AUDIT_NEVER:
765 *state = AUDIT_STATE_DISABLED;
766 break;
767 case AUDIT_ALWAYS:
768 *state = AUDIT_STATE_RECORD;
769 break;
770 }
771 return 1;
772 }
773
774 /* At process creation time, we can determine if system-call auditing is
775 * completely disabled for this task. Since we only have the task
776 * structure at this point, we can only check uid and gid.
777 */
audit_filter_task(struct task_struct * tsk,char ** key)778 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
779 {
780 struct audit_entry *e;
781 enum audit_state state;
782
783 rcu_read_lock();
784 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
785 if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
786 &state, true)) {
787 if (state == AUDIT_STATE_RECORD)
788 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
789 rcu_read_unlock();
790 return state;
791 }
792 }
793 rcu_read_unlock();
794 return AUDIT_STATE_BUILD;
795 }
796
audit_in_mask(const struct audit_krule * rule,unsigned long val)797 static int audit_in_mask(const struct audit_krule *rule, unsigned long val)
798 {
799 int word, bit;
800
801 if (val > 0xffffffff)
802 return false;
803
804 word = AUDIT_WORD(val);
805 if (word >= AUDIT_BITMASK_SIZE)
806 return false;
807
808 bit = AUDIT_BIT(val);
809
810 return rule->mask[word] & bit;
811 }
812
813 /**
814 * __audit_filter_op - common filter helper for operations (syscall/uring/etc)
815 * @tsk: associated task
816 * @ctx: audit context
817 * @list: audit filter list
818 * @name: audit_name (can be NULL)
819 * @op: current syscall/uring_op
820 *
821 * Run the udit filters specified in @list against @tsk using @ctx,
822 * @name, and @op, as necessary; the caller is responsible for ensuring
823 * that the call is made while the RCU read lock is held. The @name
824 * parameter can be NULL, but all others must be specified.
825 * Returns 1/true if the filter finds a match, 0/false if none are found.
826 */
__audit_filter_op(struct task_struct * tsk,struct audit_context * ctx,struct list_head * list,struct audit_names * name,unsigned long op)827 static int __audit_filter_op(struct task_struct *tsk,
828 struct audit_context *ctx,
829 struct list_head *list,
830 struct audit_names *name,
831 unsigned long op)
832 {
833 struct audit_entry *e;
834 enum audit_state state;
835
836 list_for_each_entry_rcu(e, list, list) {
837 if (audit_in_mask(&e->rule, op) &&
838 audit_filter_rules(tsk, &e->rule, ctx, name,
839 &state, false)) {
840 ctx->current_state = state;
841 return 1;
842 }
843 }
844 return 0;
845 }
846
847 /**
848 * audit_filter_uring - apply filters to an io_uring operation
849 * @tsk: associated task
850 * @ctx: audit context
851 */
audit_filter_uring(struct task_struct * tsk,struct audit_context * ctx)852 static void audit_filter_uring(struct task_struct *tsk,
853 struct audit_context *ctx)
854 {
855 if (auditd_test_task(tsk))
856 return;
857
858 rcu_read_lock();
859 __audit_filter_op(tsk, ctx, &audit_filter_list[AUDIT_FILTER_URING_EXIT],
860 NULL, ctx->uring_op);
861 rcu_read_unlock();
862 }
863
864 /* At syscall exit time, this filter is called if the audit_state is
865 * not low enough that auditing cannot take place, but is also not
866 * high enough that we already know we have to write an audit record
867 * (i.e., the state is AUDIT_STATE_BUILD).
868 */
audit_filter_syscall(struct task_struct * tsk,struct audit_context * ctx)869 static void audit_filter_syscall(struct task_struct *tsk,
870 struct audit_context *ctx)
871 {
872 if (auditd_test_task(tsk))
873 return;
874
875 rcu_read_lock();
876 __audit_filter_op(tsk, ctx, &audit_filter_list[AUDIT_FILTER_EXIT],
877 NULL, ctx->major);
878 rcu_read_unlock();
879 }
880
881 /*
882 * Given an audit_name check the inode hash table to see if they match.
883 * Called holding the rcu read lock to protect the use of audit_inode_hash
884 */
audit_filter_inode_name(struct task_struct * tsk,struct audit_names * n,struct audit_context * ctx)885 static int audit_filter_inode_name(struct task_struct *tsk,
886 struct audit_names *n,
887 struct audit_context *ctx)
888 {
889 int h = audit_hash_ino((u32)n->ino);
890 struct list_head *list = &audit_inode_hash[h];
891
892 return __audit_filter_op(tsk, ctx, list, n, ctx->major);
893 }
894
895 /* At syscall exit time, this filter is called if any audit_names have been
896 * collected during syscall processing. We only check rules in sublists at hash
897 * buckets applicable to the inode numbers in audit_names.
898 * Regarding audit_state, same rules apply as for audit_filter_syscall().
899 */
audit_filter_inodes(struct task_struct * tsk,struct audit_context * ctx)900 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
901 {
902 struct audit_names *n;
903
904 if (auditd_test_task(tsk))
905 return;
906
907 rcu_read_lock();
908
909 list_for_each_entry(n, &ctx->names_list, list) {
910 if (audit_filter_inode_name(tsk, n, ctx))
911 break;
912 }
913 rcu_read_unlock();
914 }
915
audit_proctitle_free(struct audit_context * context)916 static inline void audit_proctitle_free(struct audit_context *context)
917 {
918 kfree(context->proctitle.value);
919 context->proctitle.value = NULL;
920 context->proctitle.len = 0;
921 }
922
audit_free_module(struct audit_context * context)923 static inline void audit_free_module(struct audit_context *context)
924 {
925 if (context->type == AUDIT_KERN_MODULE) {
926 kfree(context->module.name);
927 context->module.name = NULL;
928 }
929 }
audit_free_names(struct audit_context * context)930 static inline void audit_free_names(struct audit_context *context)
931 {
932 struct audit_names *n, *next;
933
934 list_for_each_entry_safe(n, next, &context->names_list, list) {
935 list_del(&n->list);
936 if (n->name)
937 putname(n->name);
938 if (n->should_free)
939 kfree(n);
940 }
941 context->name_count = 0;
942 path_put(&context->pwd);
943 context->pwd.dentry = NULL;
944 context->pwd.mnt = NULL;
945 }
946
audit_free_aux(struct audit_context * context)947 static inline void audit_free_aux(struct audit_context *context)
948 {
949 struct audit_aux_data *aux;
950
951 while ((aux = context->aux)) {
952 context->aux = aux->next;
953 kfree(aux);
954 }
955 context->aux = NULL;
956 while ((aux = context->aux_pids)) {
957 context->aux_pids = aux->next;
958 kfree(aux);
959 }
960 context->aux_pids = NULL;
961 }
962
963 /**
964 * audit_reset_context - reset a audit_context structure
965 * @ctx: the audit_context to reset
966 *
967 * All fields in the audit_context will be reset to an initial state, all
968 * references held by fields will be dropped, and private memory will be
969 * released. When this function returns the audit_context will be suitable
970 * for reuse, so long as the passed context is not NULL or a dummy context.
971 */
audit_reset_context(struct audit_context * ctx)972 static void audit_reset_context(struct audit_context *ctx)
973 {
974 if (!ctx)
975 return;
976
977 /* if ctx is non-null, reset the "ctx->context" regardless */
978 ctx->context = AUDIT_CTX_UNUSED;
979 if (ctx->dummy)
980 return;
981
982 /*
983 * NOTE: It shouldn't matter in what order we release the fields, so
984 * release them in the order in which they appear in the struct;
985 * this gives us some hope of quickly making sure we are
986 * resetting the audit_context properly.
987 *
988 * Other things worth mentioning:
989 * - we don't reset "dummy"
990 * - we don't reset "state", we do reset "current_state"
991 * - we preserve "filterkey" if "state" is AUDIT_STATE_RECORD
992 * - much of this is likely overkill, but play it safe for now
993 * - we really need to work on improving the audit_context struct
994 */
995
996 ctx->current_state = ctx->state;
997 ctx->serial = 0;
998 ctx->major = 0;
999 ctx->uring_op = 0;
1000 ctx->ctime = (struct timespec64){ .tv_sec = 0, .tv_nsec = 0 };
1001 memset(ctx->argv, 0, sizeof(ctx->argv));
1002 ctx->return_code = 0;
1003 ctx->prio = (ctx->state == AUDIT_STATE_RECORD ? ~0ULL : 0);
1004 ctx->return_valid = AUDITSC_INVALID;
1005 audit_free_names(ctx);
1006 if (ctx->state != AUDIT_STATE_RECORD) {
1007 kfree(ctx->filterkey);
1008 ctx->filterkey = NULL;
1009 }
1010 audit_free_aux(ctx);
1011 kfree(ctx->sockaddr);
1012 ctx->sockaddr = NULL;
1013 ctx->sockaddr_len = 0;
1014 ctx->ppid = 0;
1015 ctx->uid = ctx->euid = ctx->suid = ctx->fsuid = KUIDT_INIT(0);
1016 ctx->gid = ctx->egid = ctx->sgid = ctx->fsgid = KGIDT_INIT(0);
1017 ctx->personality = 0;
1018 ctx->arch = 0;
1019 ctx->target_pid = 0;
1020 ctx->target_auid = ctx->target_uid = KUIDT_INIT(0);
1021 ctx->target_sessionid = 0;
1022 lsmprop_init(&ctx->target_ref);
1023 ctx->target_comm[0] = '\0';
1024 unroll_tree_refs(ctx, NULL, 0);
1025 WARN_ON(!list_empty(&ctx->killed_trees));
1026 audit_free_module(ctx);
1027 ctx->fds[0] = -1;
1028 ctx->type = 0; /* reset last for audit_free_*() */
1029 }
1030
audit_alloc_context(enum audit_state state)1031 static inline struct audit_context *audit_alloc_context(enum audit_state state)
1032 {
1033 struct audit_context *context;
1034
1035 context = kzalloc(sizeof(*context), GFP_KERNEL);
1036 if (!context)
1037 return NULL;
1038 context->context = AUDIT_CTX_UNUSED;
1039 context->state = state;
1040 context->prio = state == AUDIT_STATE_RECORD ? ~0ULL : 0;
1041 INIT_LIST_HEAD(&context->killed_trees);
1042 INIT_LIST_HEAD(&context->names_list);
1043 context->fds[0] = -1;
1044 context->return_valid = AUDITSC_INVALID;
1045 return context;
1046 }
1047
1048 /**
1049 * audit_alloc - allocate an audit context block for a task
1050 * @tsk: task
1051 *
1052 * Filter on the task information and allocate a per-task audit context
1053 * if necessary. Doing so turns on system call auditing for the
1054 * specified task. This is called from copy_process, so no lock is
1055 * needed.
1056 */
audit_alloc(struct task_struct * tsk)1057 int audit_alloc(struct task_struct *tsk)
1058 {
1059 struct audit_context *context;
1060 enum audit_state state;
1061 char *key = NULL;
1062
1063 if (likely(!audit_ever_enabled))
1064 return 0;
1065
1066 state = audit_filter_task(tsk, &key);
1067 if (state == AUDIT_STATE_DISABLED) {
1068 clear_task_syscall_work(tsk, SYSCALL_AUDIT);
1069 return 0;
1070 }
1071
1072 context = audit_alloc_context(state);
1073 if (!context) {
1074 kfree(key);
1075 audit_log_lost("out of memory in audit_alloc");
1076 return -ENOMEM;
1077 }
1078 context->filterkey = key;
1079
1080 audit_set_context(tsk, context);
1081 set_task_syscall_work(tsk, SYSCALL_AUDIT);
1082 return 0;
1083 }
1084
audit_free_context(struct audit_context * context)1085 static inline void audit_free_context(struct audit_context *context)
1086 {
1087 /* resetting is extra work, but it is likely just noise */
1088 audit_reset_context(context);
1089 audit_proctitle_free(context);
1090 free_tree_refs(context);
1091 kfree(context->filterkey);
1092 kfree(context);
1093 }
1094
audit_log_pid_context(struct audit_context * context,pid_t pid,kuid_t auid,kuid_t uid,unsigned int sessionid,struct lsm_prop * prop,char * comm)1095 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
1096 kuid_t auid, kuid_t uid,
1097 unsigned int sessionid, struct lsm_prop *prop,
1098 char *comm)
1099 {
1100 struct audit_buffer *ab;
1101 char *ctx = NULL;
1102 u32 len;
1103 int rc = 0;
1104
1105 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
1106 if (!ab)
1107 return rc;
1108
1109 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
1110 from_kuid(&init_user_ns, auid),
1111 from_kuid(&init_user_ns, uid), sessionid);
1112 if (lsmprop_is_set(prop)) {
1113 if (security_lsmprop_to_secctx(prop, &ctx, &len)) {
1114 audit_log_format(ab, " obj=(none)");
1115 rc = 1;
1116 } else {
1117 audit_log_format(ab, " obj=%s", ctx);
1118 security_release_secctx(ctx, len);
1119 }
1120 }
1121 audit_log_format(ab, " ocomm=");
1122 audit_log_untrustedstring(ab, comm);
1123 audit_log_end(ab);
1124
1125 return rc;
1126 }
1127
audit_log_execve_info(struct audit_context * context,struct audit_buffer ** ab)1128 static void audit_log_execve_info(struct audit_context *context,
1129 struct audit_buffer **ab)
1130 {
1131 long len_max;
1132 long len_rem;
1133 long len_full;
1134 long len_buf;
1135 long len_abuf = 0;
1136 long len_tmp;
1137 bool require_data;
1138 bool encode;
1139 unsigned int iter;
1140 unsigned int arg;
1141 char *buf_head;
1142 char *buf;
1143 const char __user *p = (const char __user *)current->mm->arg_start;
1144
1145 /* NOTE: this buffer needs to be large enough to hold all the non-arg
1146 * data we put in the audit record for this argument (see the
1147 * code below) ... at this point in time 96 is plenty */
1148 char abuf[96];
1149
1150 /* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the
1151 * current value of 7500 is not as important as the fact that it
1152 * is less than 8k, a setting of 7500 gives us plenty of wiggle
1153 * room if we go over a little bit in the logging below */
1154 WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500);
1155 len_max = MAX_EXECVE_AUDIT_LEN;
1156
1157 /* scratch buffer to hold the userspace args */
1158 buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1159 if (!buf_head) {
1160 audit_panic("out of memory for argv string");
1161 return;
1162 }
1163 buf = buf_head;
1164
1165 audit_log_format(*ab, "argc=%d", context->execve.argc);
1166
1167 len_rem = len_max;
1168 len_buf = 0;
1169 len_full = 0;
1170 require_data = true;
1171 encode = false;
1172 iter = 0;
1173 arg = 0;
1174 do {
1175 /* NOTE: we don't ever want to trust this value for anything
1176 * serious, but the audit record format insists we
1177 * provide an argument length for really long arguments,
1178 * e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but
1179 * to use strncpy_from_user() to obtain this value for
1180 * recording in the log, although we don't use it
1181 * anywhere here to avoid a double-fetch problem */
1182 if (len_full == 0)
1183 len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1184
1185 /* read more data from userspace */
1186 if (require_data) {
1187 /* can we make more room in the buffer? */
1188 if (buf != buf_head) {
1189 memmove(buf_head, buf, len_buf);
1190 buf = buf_head;
1191 }
1192
1193 /* fetch as much as we can of the argument */
1194 len_tmp = strncpy_from_user(&buf_head[len_buf], p,
1195 len_max - len_buf);
1196 if (len_tmp == -EFAULT) {
1197 /* unable to copy from userspace */
1198 send_sig(SIGKILL, current, 0);
1199 goto out;
1200 } else if (len_tmp == (len_max - len_buf)) {
1201 /* buffer is not large enough */
1202 require_data = true;
1203 /* NOTE: if we are going to span multiple
1204 * buffers force the encoding so we stand
1205 * a chance at a sane len_full value and
1206 * consistent record encoding */
1207 encode = true;
1208 len_full = len_full * 2;
1209 p += len_tmp;
1210 } else {
1211 require_data = false;
1212 if (!encode)
1213 encode = audit_string_contains_control(
1214 buf, len_tmp);
1215 /* try to use a trusted value for len_full */
1216 if (len_full < len_max)
1217 len_full = (encode ?
1218 len_tmp * 2 : len_tmp);
1219 p += len_tmp + 1;
1220 }
1221 len_buf += len_tmp;
1222 buf_head[len_buf] = '\0';
1223
1224 /* length of the buffer in the audit record? */
1225 len_abuf = (encode ? len_buf * 2 : len_buf + 2);
1226 }
1227
1228 /* write as much as we can to the audit log */
1229 if (len_buf >= 0) {
1230 /* NOTE: some magic numbers here - basically if we
1231 * can't fit a reasonable amount of data into the
1232 * existing audit buffer, flush it and start with
1233 * a new buffer */
1234 if ((sizeof(abuf) + 8) > len_rem) {
1235 len_rem = len_max;
1236 audit_log_end(*ab);
1237 *ab = audit_log_start(context,
1238 GFP_KERNEL, AUDIT_EXECVE);
1239 if (!*ab)
1240 goto out;
1241 }
1242
1243 /* create the non-arg portion of the arg record */
1244 len_tmp = 0;
1245 if (require_data || (iter > 0) ||
1246 ((len_abuf + sizeof(abuf)) > len_rem)) {
1247 if (iter == 0) {
1248 len_tmp += snprintf(&abuf[len_tmp],
1249 sizeof(abuf) - len_tmp,
1250 " a%d_len=%lu",
1251 arg, len_full);
1252 }
1253 len_tmp += snprintf(&abuf[len_tmp],
1254 sizeof(abuf) - len_tmp,
1255 " a%d[%d]=", arg, iter++);
1256 } else
1257 len_tmp += snprintf(&abuf[len_tmp],
1258 sizeof(abuf) - len_tmp,
1259 " a%d=", arg);
1260 WARN_ON(len_tmp >= sizeof(abuf));
1261 abuf[sizeof(abuf) - 1] = '\0';
1262
1263 /* log the arg in the audit record */
1264 audit_log_format(*ab, "%s", abuf);
1265 len_rem -= len_tmp;
1266 len_tmp = len_buf;
1267 if (encode) {
1268 if (len_abuf > len_rem)
1269 len_tmp = len_rem / 2; /* encoding */
1270 audit_log_n_hex(*ab, buf, len_tmp);
1271 len_rem -= len_tmp * 2;
1272 len_abuf -= len_tmp * 2;
1273 } else {
1274 if (len_abuf > len_rem)
1275 len_tmp = len_rem - 2; /* quotes */
1276 audit_log_n_string(*ab, buf, len_tmp);
1277 len_rem -= len_tmp + 2;
1278 /* don't subtract the "2" because we still need
1279 * to add quotes to the remaining string */
1280 len_abuf -= len_tmp;
1281 }
1282 len_buf -= len_tmp;
1283 buf += len_tmp;
1284 }
1285
1286 /* ready to move to the next argument? */
1287 if ((len_buf == 0) && !require_data) {
1288 arg++;
1289 iter = 0;
1290 len_full = 0;
1291 require_data = true;
1292 encode = false;
1293 }
1294 } while (arg < context->execve.argc);
1295
1296 /* NOTE: the caller handles the final audit_log_end() call */
1297
1298 out:
1299 kfree(buf_head);
1300 }
1301
audit_log_cap(struct audit_buffer * ab,char * prefix,kernel_cap_t * cap)1302 static void audit_log_cap(struct audit_buffer *ab, char *prefix,
1303 kernel_cap_t *cap)
1304 {
1305 if (cap_isclear(*cap)) {
1306 audit_log_format(ab, " %s=0", prefix);
1307 return;
1308 }
1309 audit_log_format(ab, " %s=%016llx", prefix, cap->val);
1310 }
1311
audit_log_fcaps(struct audit_buffer * ab,struct audit_names * name)1312 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1313 {
1314 if (name->fcap_ver == -1) {
1315 audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?");
1316 return;
1317 }
1318 audit_log_cap(ab, "cap_fp", &name->fcap.permitted);
1319 audit_log_cap(ab, "cap_fi", &name->fcap.inheritable);
1320 audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d",
1321 name->fcap.fE, name->fcap_ver,
1322 from_kuid(&init_user_ns, name->fcap.rootid));
1323 }
1324
audit_log_time(struct audit_context * context,struct audit_buffer ** ab)1325 static void audit_log_time(struct audit_context *context, struct audit_buffer **ab)
1326 {
1327 const struct audit_ntp_data *ntp = &context->time.ntp_data;
1328 const struct timespec64 *tk = &context->time.tk_injoffset;
1329 static const char * const ntp_name[] = {
1330 "offset",
1331 "freq",
1332 "status",
1333 "tai",
1334 "tick",
1335 "adjust",
1336 };
1337 int type;
1338
1339 if (context->type == AUDIT_TIME_ADJNTPVAL) {
1340 for (type = 0; type < AUDIT_NTP_NVALS; type++) {
1341 if (ntp->vals[type].newval != ntp->vals[type].oldval) {
1342 if (!*ab) {
1343 *ab = audit_log_start(context,
1344 GFP_KERNEL,
1345 AUDIT_TIME_ADJNTPVAL);
1346 if (!*ab)
1347 return;
1348 }
1349 audit_log_format(*ab, "op=%s old=%lli new=%lli",
1350 ntp_name[type],
1351 ntp->vals[type].oldval,
1352 ntp->vals[type].newval);
1353 audit_log_end(*ab);
1354 *ab = NULL;
1355 }
1356 }
1357 }
1358 if (tk->tv_sec != 0 || tk->tv_nsec != 0) {
1359 if (!*ab) {
1360 *ab = audit_log_start(context, GFP_KERNEL,
1361 AUDIT_TIME_INJOFFSET);
1362 if (!*ab)
1363 return;
1364 }
1365 audit_log_format(*ab, "sec=%lli nsec=%li",
1366 (long long)tk->tv_sec, tk->tv_nsec);
1367 audit_log_end(*ab);
1368 *ab = NULL;
1369 }
1370 }
1371
show_special(struct audit_context * context,int * call_panic)1372 static void show_special(struct audit_context *context, int *call_panic)
1373 {
1374 struct audit_buffer *ab;
1375 int i;
1376
1377 ab = audit_log_start(context, GFP_KERNEL, context->type);
1378 if (!ab)
1379 return;
1380
1381 switch (context->type) {
1382 case AUDIT_SOCKETCALL: {
1383 int nargs = context->socketcall.nargs;
1384
1385 audit_log_format(ab, "nargs=%d", nargs);
1386 for (i = 0; i < nargs; i++)
1387 audit_log_format(ab, " a%d=%lx", i,
1388 context->socketcall.args[i]);
1389 break; }
1390 case AUDIT_IPC:
1391 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1392 from_kuid(&init_user_ns, context->ipc.uid),
1393 from_kgid(&init_user_ns, context->ipc.gid),
1394 context->ipc.mode);
1395 if (lsmprop_is_set(&context->ipc.oprop)) {
1396 char *ctx = NULL;
1397 u32 len;
1398
1399 if (security_lsmprop_to_secctx(&context->ipc.oprop,
1400 &ctx, &len)) {
1401 *call_panic = 1;
1402 } else {
1403 audit_log_format(ab, " obj=%s", ctx);
1404 security_release_secctx(ctx, len);
1405 }
1406 }
1407 if (context->ipc.has_perm) {
1408 audit_log_end(ab);
1409 ab = audit_log_start(context, GFP_KERNEL,
1410 AUDIT_IPC_SET_PERM);
1411 if (unlikely(!ab))
1412 return;
1413 audit_log_format(ab,
1414 "qbytes=%lx ouid=%u ogid=%u mode=%#ho",
1415 context->ipc.qbytes,
1416 context->ipc.perm_uid,
1417 context->ipc.perm_gid,
1418 context->ipc.perm_mode);
1419 }
1420 break;
1421 case AUDIT_MQ_OPEN:
1422 audit_log_format(ab,
1423 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
1424 "mq_msgsize=%ld mq_curmsgs=%ld",
1425 context->mq_open.oflag, context->mq_open.mode,
1426 context->mq_open.attr.mq_flags,
1427 context->mq_open.attr.mq_maxmsg,
1428 context->mq_open.attr.mq_msgsize,
1429 context->mq_open.attr.mq_curmsgs);
1430 break;
1431 case AUDIT_MQ_SENDRECV:
1432 audit_log_format(ab,
1433 "mqdes=%d msg_len=%zd msg_prio=%u "
1434 "abs_timeout_sec=%lld abs_timeout_nsec=%ld",
1435 context->mq_sendrecv.mqdes,
1436 context->mq_sendrecv.msg_len,
1437 context->mq_sendrecv.msg_prio,
1438 (long long) context->mq_sendrecv.abs_timeout.tv_sec,
1439 context->mq_sendrecv.abs_timeout.tv_nsec);
1440 break;
1441 case AUDIT_MQ_NOTIFY:
1442 audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1443 context->mq_notify.mqdes,
1444 context->mq_notify.sigev_signo);
1445 break;
1446 case AUDIT_MQ_GETSETATTR: {
1447 struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1448
1449 audit_log_format(ab,
1450 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1451 "mq_curmsgs=%ld ",
1452 context->mq_getsetattr.mqdes,
1453 attr->mq_flags, attr->mq_maxmsg,
1454 attr->mq_msgsize, attr->mq_curmsgs);
1455 break; }
1456 case AUDIT_CAPSET:
1457 audit_log_format(ab, "pid=%d", context->capset.pid);
1458 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1459 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1460 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1461 audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient);
1462 break;
1463 case AUDIT_MMAP:
1464 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
1465 context->mmap.flags);
1466 break;
1467 case AUDIT_OPENAT2:
1468 audit_log_format(ab, "oflag=0%llo mode=0%llo resolve=0x%llx",
1469 context->openat2.flags,
1470 context->openat2.mode,
1471 context->openat2.resolve);
1472 break;
1473 case AUDIT_EXECVE:
1474 audit_log_execve_info(context, &ab);
1475 break;
1476 case AUDIT_KERN_MODULE:
1477 audit_log_format(ab, "name=");
1478 if (context->module.name) {
1479 audit_log_untrustedstring(ab, context->module.name);
1480 } else
1481 audit_log_format(ab, "(null)");
1482
1483 break;
1484 case AUDIT_TIME_ADJNTPVAL:
1485 case AUDIT_TIME_INJOFFSET:
1486 /* this call deviates from the rest, eating the buffer */
1487 audit_log_time(context, &ab);
1488 break;
1489 }
1490 audit_log_end(ab);
1491 }
1492
audit_proctitle_rtrim(char * proctitle,int len)1493 static inline int audit_proctitle_rtrim(char *proctitle, int len)
1494 {
1495 char *end = proctitle + len - 1;
1496
1497 while (end > proctitle && !isprint(*end))
1498 end--;
1499
1500 /* catch the case where proctitle is only 1 non-print character */
1501 len = end - proctitle + 1;
1502 len -= isprint(proctitle[len-1]) == 0;
1503 return len;
1504 }
1505
1506 /*
1507 * audit_log_name - produce AUDIT_PATH record from struct audit_names
1508 * @context: audit_context for the task
1509 * @n: audit_names structure with reportable details
1510 * @path: optional path to report instead of audit_names->name
1511 * @record_num: record number to report when handling a list of names
1512 * @call_panic: optional pointer to int that will be updated if secid fails
1513 */
audit_log_name(struct audit_context * context,struct audit_names * n,const struct path * path,int record_num,int * call_panic)1514 static void audit_log_name(struct audit_context *context, struct audit_names *n,
1515 const struct path *path, int record_num, int *call_panic)
1516 {
1517 struct audit_buffer *ab;
1518
1519 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1520 if (!ab)
1521 return;
1522
1523 audit_log_format(ab, "item=%d", record_num);
1524
1525 if (path)
1526 audit_log_d_path(ab, " name=", path);
1527 else if (n->name) {
1528 switch (n->name_len) {
1529 case AUDIT_NAME_FULL:
1530 /* log the full path */
1531 audit_log_format(ab, " name=");
1532 audit_log_untrustedstring(ab, n->name->name);
1533 break;
1534 case 0:
1535 /* name was specified as a relative path and the
1536 * directory component is the cwd
1537 */
1538 if (context->pwd.dentry && context->pwd.mnt)
1539 audit_log_d_path(ab, " name=", &context->pwd);
1540 else
1541 audit_log_format(ab, " name=(null)");
1542 break;
1543 default:
1544 /* log the name's directory component */
1545 audit_log_format(ab, " name=");
1546 audit_log_n_untrustedstring(ab, n->name->name,
1547 n->name_len);
1548 }
1549 } else
1550 audit_log_format(ab, " name=(null)");
1551
1552 if (n->ino != AUDIT_INO_UNSET)
1553 audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#ho ouid=%u ogid=%u rdev=%02x:%02x",
1554 n->ino,
1555 MAJOR(n->dev),
1556 MINOR(n->dev),
1557 n->mode,
1558 from_kuid(&init_user_ns, n->uid),
1559 from_kgid(&init_user_ns, n->gid),
1560 MAJOR(n->rdev),
1561 MINOR(n->rdev));
1562 if (lsmprop_is_set(&n->oprop)) {
1563 char *ctx = NULL;
1564 u32 len;
1565
1566 if (security_lsmprop_to_secctx(&n->oprop, &ctx, &len)) {
1567 if (call_panic)
1568 *call_panic = 2;
1569 } else {
1570 audit_log_format(ab, " obj=%s", ctx);
1571 security_release_secctx(ctx, len);
1572 }
1573 }
1574
1575 /* log the audit_names record type */
1576 switch (n->type) {
1577 case AUDIT_TYPE_NORMAL:
1578 audit_log_format(ab, " nametype=NORMAL");
1579 break;
1580 case AUDIT_TYPE_PARENT:
1581 audit_log_format(ab, " nametype=PARENT");
1582 break;
1583 case AUDIT_TYPE_CHILD_DELETE:
1584 audit_log_format(ab, " nametype=DELETE");
1585 break;
1586 case AUDIT_TYPE_CHILD_CREATE:
1587 audit_log_format(ab, " nametype=CREATE");
1588 break;
1589 default:
1590 audit_log_format(ab, " nametype=UNKNOWN");
1591 break;
1592 }
1593
1594 audit_log_fcaps(ab, n);
1595 audit_log_end(ab);
1596 }
1597
audit_log_proctitle(void)1598 static void audit_log_proctitle(void)
1599 {
1600 int res;
1601 char *buf;
1602 char *msg = "(null)";
1603 int len = strlen(msg);
1604 struct audit_context *context = audit_context();
1605 struct audit_buffer *ab;
1606
1607 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE);
1608 if (!ab)
1609 return; /* audit_panic or being filtered */
1610
1611 audit_log_format(ab, "proctitle=");
1612
1613 /* Not cached */
1614 if (!context->proctitle.value) {
1615 buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL);
1616 if (!buf)
1617 goto out;
1618 /* Historically called this from procfs naming */
1619 res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN);
1620 if (res == 0) {
1621 kfree(buf);
1622 goto out;
1623 }
1624 res = audit_proctitle_rtrim(buf, res);
1625 if (res == 0) {
1626 kfree(buf);
1627 goto out;
1628 }
1629 context->proctitle.value = buf;
1630 context->proctitle.len = res;
1631 }
1632 msg = context->proctitle.value;
1633 len = context->proctitle.len;
1634 out:
1635 audit_log_n_untrustedstring(ab, msg, len);
1636 audit_log_end(ab);
1637 }
1638
1639 /**
1640 * audit_log_uring - generate a AUDIT_URINGOP record
1641 * @ctx: the audit context
1642 */
audit_log_uring(struct audit_context * ctx)1643 static void audit_log_uring(struct audit_context *ctx)
1644 {
1645 struct audit_buffer *ab;
1646 const struct cred *cred;
1647
1648 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_URINGOP);
1649 if (!ab)
1650 return;
1651 cred = current_cred();
1652 audit_log_format(ab, "uring_op=%d", ctx->uring_op);
1653 if (ctx->return_valid != AUDITSC_INVALID)
1654 audit_log_format(ab, " success=%s exit=%ld",
1655 str_yes_no(ctx->return_valid ==
1656 AUDITSC_SUCCESS),
1657 ctx->return_code);
1658 audit_log_format(ab,
1659 " items=%d"
1660 " ppid=%d pid=%d uid=%u gid=%u euid=%u suid=%u"
1661 " fsuid=%u egid=%u sgid=%u fsgid=%u",
1662 ctx->name_count,
1663 task_ppid_nr(current), task_tgid_nr(current),
1664 from_kuid(&init_user_ns, cred->uid),
1665 from_kgid(&init_user_ns, cred->gid),
1666 from_kuid(&init_user_ns, cred->euid),
1667 from_kuid(&init_user_ns, cred->suid),
1668 from_kuid(&init_user_ns, cred->fsuid),
1669 from_kgid(&init_user_ns, cred->egid),
1670 from_kgid(&init_user_ns, cred->sgid),
1671 from_kgid(&init_user_ns, cred->fsgid));
1672 audit_log_task_context(ab);
1673 audit_log_key(ab, ctx->filterkey);
1674 audit_log_end(ab);
1675 }
1676
audit_log_exit(void)1677 static void audit_log_exit(void)
1678 {
1679 int i, call_panic = 0;
1680 struct audit_context *context = audit_context();
1681 struct audit_buffer *ab;
1682 struct audit_aux_data *aux;
1683 struct audit_names *n;
1684
1685 context->personality = current->personality;
1686
1687 switch (context->context) {
1688 case AUDIT_CTX_SYSCALL:
1689 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1690 if (!ab)
1691 return;
1692 audit_log_format(ab, "arch=%x syscall=%d",
1693 context->arch, context->major);
1694 if (context->personality != PER_LINUX)
1695 audit_log_format(ab, " per=%lx", context->personality);
1696 if (context->return_valid != AUDITSC_INVALID)
1697 audit_log_format(ab, " success=%s exit=%ld",
1698 str_yes_no(context->return_valid ==
1699 AUDITSC_SUCCESS),
1700 context->return_code);
1701 audit_log_format(ab,
1702 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d",
1703 context->argv[0],
1704 context->argv[1],
1705 context->argv[2],
1706 context->argv[3],
1707 context->name_count);
1708 audit_log_task_info(ab);
1709 audit_log_key(ab, context->filterkey);
1710 audit_log_end(ab);
1711 break;
1712 case AUDIT_CTX_URING:
1713 audit_log_uring(context);
1714 break;
1715 default:
1716 BUG();
1717 break;
1718 }
1719
1720 for (aux = context->aux; aux; aux = aux->next) {
1721
1722 ab = audit_log_start(context, GFP_KERNEL, aux->type);
1723 if (!ab)
1724 continue; /* audit_panic has been called */
1725
1726 switch (aux->type) {
1727
1728 case AUDIT_BPRM_FCAPS: {
1729 struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1730
1731 audit_log_format(ab, "fver=%x", axs->fcap_ver);
1732 audit_log_cap(ab, "fp", &axs->fcap.permitted);
1733 audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1734 audit_log_format(ab, " fe=%d", axs->fcap.fE);
1735 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1736 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1737 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1738 audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient);
1739 audit_log_cap(ab, "pp", &axs->new_pcap.permitted);
1740 audit_log_cap(ab, "pi", &axs->new_pcap.inheritable);
1741 audit_log_cap(ab, "pe", &axs->new_pcap.effective);
1742 audit_log_cap(ab, "pa", &axs->new_pcap.ambient);
1743 audit_log_format(ab, " frootid=%d",
1744 from_kuid(&init_user_ns,
1745 axs->fcap.rootid));
1746 break; }
1747
1748 }
1749 audit_log_end(ab);
1750 }
1751
1752 if (context->type)
1753 show_special(context, &call_panic);
1754
1755 if (context->fds[0] >= 0) {
1756 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1757 if (ab) {
1758 audit_log_format(ab, "fd0=%d fd1=%d",
1759 context->fds[0], context->fds[1]);
1760 audit_log_end(ab);
1761 }
1762 }
1763
1764 if (context->sockaddr_len) {
1765 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1766 if (ab) {
1767 audit_log_format(ab, "saddr=");
1768 audit_log_n_hex(ab, (void *)context->sockaddr,
1769 context->sockaddr_len);
1770 audit_log_end(ab);
1771 }
1772 }
1773
1774 for (aux = context->aux_pids; aux; aux = aux->next) {
1775 struct audit_aux_data_pids *axs = (void *)aux;
1776
1777 for (i = 0; i < axs->pid_count; i++)
1778 if (audit_log_pid_context(context, axs->target_pid[i],
1779 axs->target_auid[i],
1780 axs->target_uid[i],
1781 axs->target_sessionid[i],
1782 &axs->target_ref[i],
1783 axs->target_comm[i]))
1784 call_panic = 1;
1785 }
1786
1787 if (context->target_pid &&
1788 audit_log_pid_context(context, context->target_pid,
1789 context->target_auid, context->target_uid,
1790 context->target_sessionid,
1791 &context->target_ref, context->target_comm))
1792 call_panic = 1;
1793
1794 if (context->pwd.dentry && context->pwd.mnt) {
1795 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1796 if (ab) {
1797 audit_log_d_path(ab, "cwd=", &context->pwd);
1798 audit_log_end(ab);
1799 }
1800 }
1801
1802 i = 0;
1803 list_for_each_entry(n, &context->names_list, list) {
1804 if (n->hidden)
1805 continue;
1806 audit_log_name(context, n, NULL, i++, &call_panic);
1807 }
1808
1809 if (context->context == AUDIT_CTX_SYSCALL)
1810 audit_log_proctitle();
1811
1812 /* Send end of event record to help user space know we are finished */
1813 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1814 if (ab)
1815 audit_log_end(ab);
1816 if (call_panic)
1817 audit_panic("error in audit_log_exit()");
1818 }
1819
1820 /**
1821 * __audit_free - free a per-task audit context
1822 * @tsk: task whose audit context block to free
1823 *
1824 * Called from copy_process, do_exit, and the io_uring code
1825 */
__audit_free(struct task_struct * tsk)1826 void __audit_free(struct task_struct *tsk)
1827 {
1828 struct audit_context *context = tsk->audit_context;
1829
1830 if (!context)
1831 return;
1832
1833 /* this may generate CONFIG_CHANGE records */
1834 if (!list_empty(&context->killed_trees))
1835 audit_kill_trees(context);
1836
1837 /* We are called either by do_exit() or the fork() error handling code;
1838 * in the former case tsk == current and in the latter tsk is a
1839 * random task_struct that doesn't have any meaningful data we
1840 * need to log via audit_log_exit().
1841 */
1842 if (tsk == current && !context->dummy) {
1843 context->return_valid = AUDITSC_INVALID;
1844 context->return_code = 0;
1845 if (context->context == AUDIT_CTX_SYSCALL) {
1846 audit_filter_syscall(tsk, context);
1847 audit_filter_inodes(tsk, context);
1848 if (context->current_state == AUDIT_STATE_RECORD)
1849 audit_log_exit();
1850 } else if (context->context == AUDIT_CTX_URING) {
1851 /* TODO: verify this case is real and valid */
1852 audit_filter_uring(tsk, context);
1853 audit_filter_inodes(tsk, context);
1854 if (context->current_state == AUDIT_STATE_RECORD)
1855 audit_log_uring(context);
1856 }
1857 }
1858
1859 audit_set_context(tsk, NULL);
1860 audit_free_context(context);
1861 }
1862
1863 /**
1864 * audit_return_fixup - fixup the return codes in the audit_context
1865 * @ctx: the audit_context
1866 * @success: true/false value to indicate if the operation succeeded or not
1867 * @code: operation return code
1868 *
1869 * We need to fixup the return code in the audit logs if the actual return
1870 * codes are later going to be fixed by the arch specific signal handlers.
1871 */
audit_return_fixup(struct audit_context * ctx,int success,long code)1872 static void audit_return_fixup(struct audit_context *ctx,
1873 int success, long code)
1874 {
1875 /*
1876 * This is actually a test for:
1877 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
1878 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
1879 *
1880 * but is faster than a bunch of ||
1881 */
1882 if (unlikely(code <= -ERESTARTSYS) &&
1883 (code >= -ERESTART_RESTARTBLOCK) &&
1884 (code != -ENOIOCTLCMD))
1885 ctx->return_code = -EINTR;
1886 else
1887 ctx->return_code = code;
1888 ctx->return_valid = (success ? AUDITSC_SUCCESS : AUDITSC_FAILURE);
1889 }
1890
1891 /**
1892 * __audit_uring_entry - prepare the kernel task's audit context for io_uring
1893 * @op: the io_uring opcode
1894 *
1895 * This is similar to audit_syscall_entry() but is intended for use by io_uring
1896 * operations. This function should only ever be called from
1897 * audit_uring_entry() as we rely on the audit context checking present in that
1898 * function.
1899 */
__audit_uring_entry(u8 op)1900 void __audit_uring_entry(u8 op)
1901 {
1902 struct audit_context *ctx = audit_context();
1903
1904 if (ctx->state == AUDIT_STATE_DISABLED)
1905 return;
1906
1907 /*
1908 * NOTE: It's possible that we can be called from the process' context
1909 * before it returns to userspace, and before audit_syscall_exit()
1910 * is called. In this case there is not much to do, just record
1911 * the io_uring details and return.
1912 */
1913 ctx->uring_op = op;
1914 if (ctx->context == AUDIT_CTX_SYSCALL)
1915 return;
1916
1917 ctx->dummy = !audit_n_rules;
1918 if (!ctx->dummy && ctx->state == AUDIT_STATE_BUILD)
1919 ctx->prio = 0;
1920
1921 ctx->context = AUDIT_CTX_URING;
1922 ctx->current_state = ctx->state;
1923 ktime_get_coarse_real_ts64(&ctx->ctime);
1924 }
1925
1926 /**
1927 * __audit_uring_exit - wrap up the kernel task's audit context after io_uring
1928 * @success: true/false value to indicate if the operation succeeded or not
1929 * @code: operation return code
1930 *
1931 * This is similar to audit_syscall_exit() but is intended for use by io_uring
1932 * operations. This function should only ever be called from
1933 * audit_uring_exit() as we rely on the audit context checking present in that
1934 * function.
1935 */
__audit_uring_exit(int success,long code)1936 void __audit_uring_exit(int success, long code)
1937 {
1938 struct audit_context *ctx = audit_context();
1939
1940 if (ctx->dummy) {
1941 if (ctx->context != AUDIT_CTX_URING)
1942 return;
1943 goto out;
1944 }
1945
1946 audit_return_fixup(ctx, success, code);
1947 if (ctx->context == AUDIT_CTX_SYSCALL) {
1948 /*
1949 * NOTE: See the note in __audit_uring_entry() about the case
1950 * where we may be called from process context before we
1951 * return to userspace via audit_syscall_exit(). In this
1952 * case we simply emit a URINGOP record and bail, the
1953 * normal syscall exit handling will take care of
1954 * everything else.
1955 * It is also worth mentioning that when we are called,
1956 * the current process creds may differ from the creds
1957 * used during the normal syscall processing; keep that
1958 * in mind if/when we move the record generation code.
1959 */
1960
1961 /*
1962 * We need to filter on the syscall info here to decide if we
1963 * should emit a URINGOP record. I know it seems odd but this
1964 * solves the problem where users have a filter to block *all*
1965 * syscall records in the "exit" filter; we want to preserve
1966 * the behavior here.
1967 */
1968 audit_filter_syscall(current, ctx);
1969 if (ctx->current_state != AUDIT_STATE_RECORD)
1970 audit_filter_uring(current, ctx);
1971 audit_filter_inodes(current, ctx);
1972 if (ctx->current_state != AUDIT_STATE_RECORD)
1973 return;
1974
1975 audit_log_uring(ctx);
1976 return;
1977 }
1978
1979 /* this may generate CONFIG_CHANGE records */
1980 if (!list_empty(&ctx->killed_trees))
1981 audit_kill_trees(ctx);
1982
1983 /* run through both filters to ensure we set the filterkey properly */
1984 audit_filter_uring(current, ctx);
1985 audit_filter_inodes(current, ctx);
1986 if (ctx->current_state != AUDIT_STATE_RECORD)
1987 goto out;
1988 audit_log_exit();
1989
1990 out:
1991 audit_reset_context(ctx);
1992 }
1993
1994 /**
1995 * __audit_syscall_entry - fill in an audit record at syscall entry
1996 * @major: major syscall type (function)
1997 * @a1: additional syscall register 1
1998 * @a2: additional syscall register 2
1999 * @a3: additional syscall register 3
2000 * @a4: additional syscall register 4
2001 *
2002 * Fill in audit context at syscall entry. This only happens if the
2003 * audit context was created when the task was created and the state or
2004 * filters demand the audit context be built. If the state from the
2005 * per-task filter or from the per-syscall filter is AUDIT_STATE_RECORD,
2006 * then the record will be written at syscall exit time (otherwise, it
2007 * will only be written if another part of the kernel requests that it
2008 * be written).
2009 */
__audit_syscall_entry(int major,unsigned long a1,unsigned long a2,unsigned long a3,unsigned long a4)2010 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
2011 unsigned long a3, unsigned long a4)
2012 {
2013 struct audit_context *context = audit_context();
2014 enum audit_state state;
2015
2016 if (!audit_enabled || !context)
2017 return;
2018
2019 WARN_ON(context->context != AUDIT_CTX_UNUSED);
2020 WARN_ON(context->name_count);
2021 if (context->context != AUDIT_CTX_UNUSED || context->name_count) {
2022 audit_panic("unrecoverable error in audit_syscall_entry()");
2023 return;
2024 }
2025
2026 state = context->state;
2027 if (state == AUDIT_STATE_DISABLED)
2028 return;
2029
2030 context->dummy = !audit_n_rules;
2031 if (!context->dummy && state == AUDIT_STATE_BUILD) {
2032 context->prio = 0;
2033 if (auditd_test_task(current))
2034 return;
2035 }
2036
2037 context->arch = syscall_get_arch(current);
2038 context->major = major;
2039 context->argv[0] = a1;
2040 context->argv[1] = a2;
2041 context->argv[2] = a3;
2042 context->argv[3] = a4;
2043 context->context = AUDIT_CTX_SYSCALL;
2044 context->current_state = state;
2045 ktime_get_coarse_real_ts64(&context->ctime);
2046 }
2047
2048 /**
2049 * __audit_syscall_exit - deallocate audit context after a system call
2050 * @success: success value of the syscall
2051 * @return_code: return value of the syscall
2052 *
2053 * Tear down after system call. If the audit context has been marked as
2054 * auditable (either because of the AUDIT_STATE_RECORD state from
2055 * filtering, or because some other part of the kernel wrote an audit
2056 * message), then write out the syscall information. In call cases,
2057 * free the names stored from getname().
2058 */
__audit_syscall_exit(int success,long return_code)2059 void __audit_syscall_exit(int success, long return_code)
2060 {
2061 struct audit_context *context = audit_context();
2062
2063 if (!context || context->dummy ||
2064 context->context != AUDIT_CTX_SYSCALL)
2065 goto out;
2066
2067 /* this may generate CONFIG_CHANGE records */
2068 if (!list_empty(&context->killed_trees))
2069 audit_kill_trees(context);
2070
2071 audit_return_fixup(context, success, return_code);
2072 /* run through both filters to ensure we set the filterkey properly */
2073 audit_filter_syscall(current, context);
2074 audit_filter_inodes(current, context);
2075 if (context->current_state != AUDIT_STATE_RECORD)
2076 goto out;
2077
2078 audit_log_exit();
2079
2080 out:
2081 audit_reset_context(context);
2082 }
2083
handle_one(const struct inode * inode)2084 static inline void handle_one(const struct inode *inode)
2085 {
2086 struct audit_context *context;
2087 struct audit_tree_refs *p;
2088 struct audit_chunk *chunk;
2089 int count;
2090
2091 if (likely(!inode->i_fsnotify_marks))
2092 return;
2093 context = audit_context();
2094 p = context->trees;
2095 count = context->tree_count;
2096 rcu_read_lock();
2097 chunk = audit_tree_lookup(inode);
2098 rcu_read_unlock();
2099 if (!chunk)
2100 return;
2101 if (likely(put_tree_ref(context, chunk)))
2102 return;
2103 if (unlikely(!grow_tree_refs(context))) {
2104 pr_warn("out of memory, audit has lost a tree reference\n");
2105 audit_set_auditable(context);
2106 audit_put_chunk(chunk);
2107 unroll_tree_refs(context, p, count);
2108 return;
2109 }
2110 put_tree_ref(context, chunk);
2111 }
2112
handle_path(const struct dentry * dentry)2113 static void handle_path(const struct dentry *dentry)
2114 {
2115 struct audit_context *context;
2116 struct audit_tree_refs *p;
2117 const struct dentry *d, *parent;
2118 struct audit_chunk *drop;
2119 unsigned long seq;
2120 int count;
2121
2122 context = audit_context();
2123 p = context->trees;
2124 count = context->tree_count;
2125 retry:
2126 drop = NULL;
2127 d = dentry;
2128 rcu_read_lock();
2129 seq = read_seqbegin(&rename_lock);
2130 for (;;) {
2131 struct inode *inode = d_backing_inode(d);
2132
2133 if (inode && unlikely(inode->i_fsnotify_marks)) {
2134 struct audit_chunk *chunk;
2135
2136 chunk = audit_tree_lookup(inode);
2137 if (chunk) {
2138 if (unlikely(!put_tree_ref(context, chunk))) {
2139 drop = chunk;
2140 break;
2141 }
2142 }
2143 }
2144 parent = d->d_parent;
2145 if (parent == d)
2146 break;
2147 d = parent;
2148 }
2149 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */
2150 rcu_read_unlock();
2151 if (!drop) {
2152 /* just a race with rename */
2153 unroll_tree_refs(context, p, count);
2154 goto retry;
2155 }
2156 audit_put_chunk(drop);
2157 if (grow_tree_refs(context)) {
2158 /* OK, got more space */
2159 unroll_tree_refs(context, p, count);
2160 goto retry;
2161 }
2162 /* too bad */
2163 pr_warn("out of memory, audit has lost a tree reference\n");
2164 unroll_tree_refs(context, p, count);
2165 audit_set_auditable(context);
2166 return;
2167 }
2168 rcu_read_unlock();
2169 }
2170
audit_alloc_name(struct audit_context * context,unsigned char type)2171 static struct audit_names *audit_alloc_name(struct audit_context *context,
2172 unsigned char type)
2173 {
2174 struct audit_names *aname;
2175
2176 if (context->name_count < AUDIT_NAMES) {
2177 aname = &context->preallocated_names[context->name_count];
2178 memset(aname, 0, sizeof(*aname));
2179 } else {
2180 aname = kzalloc(sizeof(*aname), GFP_NOFS);
2181 if (!aname)
2182 return NULL;
2183 aname->should_free = true;
2184 }
2185
2186 aname->ino = AUDIT_INO_UNSET;
2187 aname->type = type;
2188 list_add_tail(&aname->list, &context->names_list);
2189
2190 context->name_count++;
2191 if (!context->pwd.dentry)
2192 get_fs_pwd(current->fs, &context->pwd);
2193 return aname;
2194 }
2195
2196 /**
2197 * __audit_reusename - fill out filename with info from existing entry
2198 * @uptr: userland ptr to pathname
2199 *
2200 * Search the audit_names list for the current audit context. If there is an
2201 * existing entry with a matching "uptr" then return the filename
2202 * associated with that audit_name. If not, return NULL.
2203 */
2204 struct filename *
__audit_reusename(const __user char * uptr)2205 __audit_reusename(const __user char *uptr)
2206 {
2207 struct audit_context *context = audit_context();
2208 struct audit_names *n;
2209
2210 list_for_each_entry(n, &context->names_list, list) {
2211 if (!n->name)
2212 continue;
2213 if (n->name->uptr == uptr) {
2214 atomic_inc(&n->name->refcnt);
2215 return n->name;
2216 }
2217 }
2218 return NULL;
2219 }
2220
2221 /**
2222 * __audit_getname - add a name to the list
2223 * @name: name to add
2224 *
2225 * Add a name to the list of audit names for this context.
2226 * Called from fs/namei.c:getname().
2227 */
__audit_getname(struct filename * name)2228 void __audit_getname(struct filename *name)
2229 {
2230 struct audit_context *context = audit_context();
2231 struct audit_names *n;
2232
2233 if (context->context == AUDIT_CTX_UNUSED)
2234 return;
2235
2236 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2237 if (!n)
2238 return;
2239
2240 n->name = name;
2241 n->name_len = AUDIT_NAME_FULL;
2242 name->aname = n;
2243 atomic_inc(&name->refcnt);
2244 }
2245
audit_copy_fcaps(struct audit_names * name,const struct dentry * dentry)2246 static inline int audit_copy_fcaps(struct audit_names *name,
2247 const struct dentry *dentry)
2248 {
2249 struct cpu_vfs_cap_data caps;
2250 int rc;
2251
2252 if (!dentry)
2253 return 0;
2254
2255 rc = get_vfs_caps_from_disk(&nop_mnt_idmap, dentry, &caps);
2256 if (rc)
2257 return rc;
2258
2259 name->fcap.permitted = caps.permitted;
2260 name->fcap.inheritable = caps.inheritable;
2261 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2262 name->fcap.rootid = caps.rootid;
2263 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >>
2264 VFS_CAP_REVISION_SHIFT;
2265
2266 return 0;
2267 }
2268
2269 /* Copy inode data into an audit_names. */
audit_copy_inode(struct audit_names * name,const struct dentry * dentry,struct inode * inode,unsigned int flags)2270 static void audit_copy_inode(struct audit_names *name,
2271 const struct dentry *dentry,
2272 struct inode *inode, unsigned int flags)
2273 {
2274 name->ino = inode->i_ino;
2275 name->dev = inode->i_sb->s_dev;
2276 name->mode = inode->i_mode;
2277 name->uid = inode->i_uid;
2278 name->gid = inode->i_gid;
2279 name->rdev = inode->i_rdev;
2280 security_inode_getlsmprop(inode, &name->oprop);
2281 if (flags & AUDIT_INODE_NOEVAL) {
2282 name->fcap_ver = -1;
2283 return;
2284 }
2285 audit_copy_fcaps(name, dentry);
2286 }
2287
2288 /**
2289 * __audit_inode - store the inode and device from a lookup
2290 * @name: name being audited
2291 * @dentry: dentry being audited
2292 * @flags: attributes for this particular entry
2293 */
__audit_inode(struct filename * name,const struct dentry * dentry,unsigned int flags)2294 void __audit_inode(struct filename *name, const struct dentry *dentry,
2295 unsigned int flags)
2296 {
2297 struct audit_context *context = audit_context();
2298 struct inode *inode = d_backing_inode(dentry);
2299 struct audit_names *n;
2300 bool parent = flags & AUDIT_INODE_PARENT;
2301 struct audit_entry *e;
2302 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
2303 int i;
2304
2305 if (context->context == AUDIT_CTX_UNUSED)
2306 return;
2307
2308 rcu_read_lock();
2309 list_for_each_entry_rcu(e, list, list) {
2310 for (i = 0; i < e->rule.field_count; i++) {
2311 struct audit_field *f = &e->rule.fields[i];
2312
2313 if (f->type == AUDIT_FSTYPE
2314 && audit_comparator(inode->i_sb->s_magic,
2315 f->op, f->val)
2316 && e->rule.action == AUDIT_NEVER) {
2317 rcu_read_unlock();
2318 return;
2319 }
2320 }
2321 }
2322 rcu_read_unlock();
2323
2324 if (!name)
2325 goto out_alloc;
2326
2327 /*
2328 * If we have a pointer to an audit_names entry already, then we can
2329 * just use it directly if the type is correct.
2330 */
2331 n = name->aname;
2332 if (n) {
2333 if (parent) {
2334 if (n->type == AUDIT_TYPE_PARENT ||
2335 n->type == AUDIT_TYPE_UNKNOWN)
2336 goto out;
2337 } else {
2338 if (n->type != AUDIT_TYPE_PARENT)
2339 goto out;
2340 }
2341 }
2342
2343 list_for_each_entry_reverse(n, &context->names_list, list) {
2344 if (n->ino) {
2345 /* valid inode number, use that for the comparison */
2346 if (n->ino != inode->i_ino ||
2347 n->dev != inode->i_sb->s_dev)
2348 continue;
2349 } else if (n->name) {
2350 /* inode number has not been set, check the name */
2351 if (strcmp(n->name->name, name->name))
2352 continue;
2353 } else
2354 /* no inode and no name (?!) ... this is odd ... */
2355 continue;
2356
2357 /* match the correct record type */
2358 if (parent) {
2359 if (n->type == AUDIT_TYPE_PARENT ||
2360 n->type == AUDIT_TYPE_UNKNOWN)
2361 goto out;
2362 } else {
2363 if (n->type != AUDIT_TYPE_PARENT)
2364 goto out;
2365 }
2366 }
2367
2368 out_alloc:
2369 /* unable to find an entry with both a matching name and type */
2370 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2371 if (!n)
2372 return;
2373 if (name) {
2374 n->name = name;
2375 atomic_inc(&name->refcnt);
2376 }
2377
2378 out:
2379 if (parent) {
2380 n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
2381 n->type = AUDIT_TYPE_PARENT;
2382 if (flags & AUDIT_INODE_HIDDEN)
2383 n->hidden = true;
2384 } else {
2385 n->name_len = AUDIT_NAME_FULL;
2386 n->type = AUDIT_TYPE_NORMAL;
2387 }
2388 handle_path(dentry);
2389 audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL);
2390 }
2391
__audit_file(const struct file * file)2392 void __audit_file(const struct file *file)
2393 {
2394 __audit_inode(NULL, file->f_path.dentry, 0);
2395 }
2396
2397 /**
2398 * __audit_inode_child - collect inode info for created/removed objects
2399 * @parent: inode of dentry parent
2400 * @dentry: dentry being audited
2401 * @type: AUDIT_TYPE_* value that we're looking for
2402 *
2403 * For syscalls that create or remove filesystem objects, audit_inode
2404 * can only collect information for the filesystem object's parent.
2405 * This call updates the audit context with the child's information.
2406 * Syscalls that create a new filesystem object must be hooked after
2407 * the object is created. Syscalls that remove a filesystem object
2408 * must be hooked prior, in order to capture the target inode during
2409 * unsuccessful attempts.
2410 */
__audit_inode_child(struct inode * parent,const struct dentry * dentry,const unsigned char type)2411 void __audit_inode_child(struct inode *parent,
2412 const struct dentry *dentry,
2413 const unsigned char type)
2414 {
2415 struct audit_context *context = audit_context();
2416 struct inode *inode = d_backing_inode(dentry);
2417 const struct qstr *dname = &dentry->d_name;
2418 struct audit_names *n, *found_parent = NULL, *found_child = NULL;
2419 struct audit_entry *e;
2420 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
2421 int i;
2422
2423 if (context->context == AUDIT_CTX_UNUSED)
2424 return;
2425
2426 rcu_read_lock();
2427 list_for_each_entry_rcu(e, list, list) {
2428 for (i = 0; i < e->rule.field_count; i++) {
2429 struct audit_field *f = &e->rule.fields[i];
2430
2431 if (f->type == AUDIT_FSTYPE
2432 && audit_comparator(parent->i_sb->s_magic,
2433 f->op, f->val)
2434 && e->rule.action == AUDIT_NEVER) {
2435 rcu_read_unlock();
2436 return;
2437 }
2438 }
2439 }
2440 rcu_read_unlock();
2441
2442 if (inode)
2443 handle_one(inode);
2444
2445 /* look for a parent entry first */
2446 list_for_each_entry(n, &context->names_list, list) {
2447 if (!n->name ||
2448 (n->type != AUDIT_TYPE_PARENT &&
2449 n->type != AUDIT_TYPE_UNKNOWN))
2450 continue;
2451
2452 if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev &&
2453 !audit_compare_dname_path(dname,
2454 n->name->name, n->name_len)) {
2455 if (n->type == AUDIT_TYPE_UNKNOWN)
2456 n->type = AUDIT_TYPE_PARENT;
2457 found_parent = n;
2458 break;
2459 }
2460 }
2461
2462 cond_resched();
2463
2464 /* is there a matching child entry? */
2465 list_for_each_entry(n, &context->names_list, list) {
2466 /* can only match entries that have a name */
2467 if (!n->name ||
2468 (n->type != type && n->type != AUDIT_TYPE_UNKNOWN))
2469 continue;
2470
2471 if (!strcmp(dname->name, n->name->name) ||
2472 !audit_compare_dname_path(dname, n->name->name,
2473 found_parent ?
2474 found_parent->name_len :
2475 AUDIT_NAME_FULL)) {
2476 if (n->type == AUDIT_TYPE_UNKNOWN)
2477 n->type = type;
2478 found_child = n;
2479 break;
2480 }
2481 }
2482
2483 if (!found_parent) {
2484 /* create a new, "anonymous" parent record */
2485 n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
2486 if (!n)
2487 return;
2488 audit_copy_inode(n, NULL, parent, 0);
2489 }
2490
2491 if (!found_child) {
2492 found_child = audit_alloc_name(context, type);
2493 if (!found_child)
2494 return;
2495
2496 /* Re-use the name belonging to the slot for a matching parent
2497 * directory. All names for this context are relinquished in
2498 * audit_free_names() */
2499 if (found_parent) {
2500 found_child->name = found_parent->name;
2501 found_child->name_len = AUDIT_NAME_FULL;
2502 atomic_inc(&found_child->name->refcnt);
2503 }
2504 }
2505
2506 if (inode)
2507 audit_copy_inode(found_child, dentry, inode, 0);
2508 else
2509 found_child->ino = AUDIT_INO_UNSET;
2510 }
2511 EXPORT_SYMBOL_GPL(__audit_inode_child);
2512
2513 /**
2514 * auditsc_get_stamp - get local copies of audit_context values
2515 * @ctx: audit_context for the task
2516 * @t: timespec64 to store time recorded in the audit_context
2517 * @serial: serial value that is recorded in the audit_context
2518 *
2519 * Also sets the context as auditable.
2520 */
auditsc_get_stamp(struct audit_context * ctx,struct timespec64 * t,unsigned int * serial)2521 int auditsc_get_stamp(struct audit_context *ctx,
2522 struct timespec64 *t, unsigned int *serial)
2523 {
2524 if (ctx->context == AUDIT_CTX_UNUSED)
2525 return 0;
2526 if (!ctx->serial)
2527 ctx->serial = audit_serial();
2528 t->tv_sec = ctx->ctime.tv_sec;
2529 t->tv_nsec = ctx->ctime.tv_nsec;
2530 *serial = ctx->serial;
2531 if (!ctx->prio) {
2532 ctx->prio = 1;
2533 ctx->current_state = AUDIT_STATE_RECORD;
2534 }
2535 return 1;
2536 }
2537
2538 /**
2539 * __audit_mq_open - record audit data for a POSIX MQ open
2540 * @oflag: open flag
2541 * @mode: mode bits
2542 * @attr: queue attributes
2543 *
2544 */
__audit_mq_open(int oflag,umode_t mode,struct mq_attr * attr)2545 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2546 {
2547 struct audit_context *context = audit_context();
2548
2549 if (attr)
2550 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2551 else
2552 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2553
2554 context->mq_open.oflag = oflag;
2555 context->mq_open.mode = mode;
2556
2557 context->type = AUDIT_MQ_OPEN;
2558 }
2559
2560 /**
2561 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2562 * @mqdes: MQ descriptor
2563 * @msg_len: Message length
2564 * @msg_prio: Message priority
2565 * @abs_timeout: Message timeout in absolute time
2566 *
2567 */
__audit_mq_sendrecv(mqd_t mqdes,size_t msg_len,unsigned int msg_prio,const struct timespec64 * abs_timeout)2568 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2569 const struct timespec64 *abs_timeout)
2570 {
2571 struct audit_context *context = audit_context();
2572 struct timespec64 *p = &context->mq_sendrecv.abs_timeout;
2573
2574 if (abs_timeout)
2575 memcpy(p, abs_timeout, sizeof(*p));
2576 else
2577 memset(p, 0, sizeof(*p));
2578
2579 context->mq_sendrecv.mqdes = mqdes;
2580 context->mq_sendrecv.msg_len = msg_len;
2581 context->mq_sendrecv.msg_prio = msg_prio;
2582
2583 context->type = AUDIT_MQ_SENDRECV;
2584 }
2585
2586 /**
2587 * __audit_mq_notify - record audit data for a POSIX MQ notify
2588 * @mqdes: MQ descriptor
2589 * @notification: Notification event
2590 *
2591 */
2592
__audit_mq_notify(mqd_t mqdes,const struct sigevent * notification)2593 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2594 {
2595 struct audit_context *context = audit_context();
2596
2597 if (notification)
2598 context->mq_notify.sigev_signo = notification->sigev_signo;
2599 else
2600 context->mq_notify.sigev_signo = 0;
2601
2602 context->mq_notify.mqdes = mqdes;
2603 context->type = AUDIT_MQ_NOTIFY;
2604 }
2605
2606 /**
2607 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2608 * @mqdes: MQ descriptor
2609 * @mqstat: MQ flags
2610 *
2611 */
__audit_mq_getsetattr(mqd_t mqdes,struct mq_attr * mqstat)2612 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2613 {
2614 struct audit_context *context = audit_context();
2615
2616 context->mq_getsetattr.mqdes = mqdes;
2617 context->mq_getsetattr.mqstat = *mqstat;
2618 context->type = AUDIT_MQ_GETSETATTR;
2619 }
2620
2621 /**
2622 * __audit_ipc_obj - record audit data for ipc object
2623 * @ipcp: ipc permissions
2624 *
2625 */
__audit_ipc_obj(struct kern_ipc_perm * ipcp)2626 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2627 {
2628 struct audit_context *context = audit_context();
2629
2630 context->ipc.uid = ipcp->uid;
2631 context->ipc.gid = ipcp->gid;
2632 context->ipc.mode = ipcp->mode;
2633 context->ipc.has_perm = 0;
2634 security_ipc_getlsmprop(ipcp, &context->ipc.oprop);
2635 context->type = AUDIT_IPC;
2636 }
2637
2638 /**
2639 * __audit_ipc_set_perm - record audit data for new ipc permissions
2640 * @qbytes: msgq bytes
2641 * @uid: msgq user id
2642 * @gid: msgq group id
2643 * @mode: msgq mode (permissions)
2644 *
2645 * Called only after audit_ipc_obj().
2646 */
__audit_ipc_set_perm(unsigned long qbytes,uid_t uid,gid_t gid,umode_t mode)2647 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
2648 {
2649 struct audit_context *context = audit_context();
2650
2651 context->ipc.qbytes = qbytes;
2652 context->ipc.perm_uid = uid;
2653 context->ipc.perm_gid = gid;
2654 context->ipc.perm_mode = mode;
2655 context->ipc.has_perm = 1;
2656 }
2657
__audit_bprm(struct linux_binprm * bprm)2658 void __audit_bprm(struct linux_binprm *bprm)
2659 {
2660 struct audit_context *context = audit_context();
2661
2662 context->type = AUDIT_EXECVE;
2663 context->execve.argc = bprm->argc;
2664 }
2665
2666
2667 /**
2668 * __audit_socketcall - record audit data for sys_socketcall
2669 * @nargs: number of args, which should not be more than AUDITSC_ARGS.
2670 * @args: args array
2671 *
2672 */
__audit_socketcall(int nargs,unsigned long * args)2673 int __audit_socketcall(int nargs, unsigned long *args)
2674 {
2675 struct audit_context *context = audit_context();
2676
2677 if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
2678 return -EINVAL;
2679 context->type = AUDIT_SOCKETCALL;
2680 context->socketcall.nargs = nargs;
2681 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2682 return 0;
2683 }
2684
2685 /**
2686 * __audit_fd_pair - record audit data for pipe and socketpair
2687 * @fd1: the first file descriptor
2688 * @fd2: the second file descriptor
2689 *
2690 */
__audit_fd_pair(int fd1,int fd2)2691 void __audit_fd_pair(int fd1, int fd2)
2692 {
2693 struct audit_context *context = audit_context();
2694
2695 context->fds[0] = fd1;
2696 context->fds[1] = fd2;
2697 }
2698
2699 /**
2700 * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2701 * @len: data length in user space
2702 * @a: data address in kernel space
2703 *
2704 * Returns 0 for success or NULL context or < 0 on error.
2705 */
__audit_sockaddr(int len,void * a)2706 int __audit_sockaddr(int len, void *a)
2707 {
2708 struct audit_context *context = audit_context();
2709
2710 if (!context->sockaddr) {
2711 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2712
2713 if (!p)
2714 return -ENOMEM;
2715 context->sockaddr = p;
2716 }
2717
2718 context->sockaddr_len = len;
2719 memcpy(context->sockaddr, a, len);
2720 return 0;
2721 }
2722
__audit_ptrace(struct task_struct * t)2723 void __audit_ptrace(struct task_struct *t)
2724 {
2725 struct audit_context *context = audit_context();
2726
2727 context->target_pid = task_tgid_nr(t);
2728 context->target_auid = audit_get_loginuid(t);
2729 context->target_uid = task_uid(t);
2730 context->target_sessionid = audit_get_sessionid(t);
2731 strscpy(context->target_comm, t->comm);
2732 security_task_getlsmprop_obj(t, &context->target_ref);
2733 }
2734
2735 /**
2736 * audit_signal_info_syscall - record signal info for syscalls
2737 * @t: task being signaled
2738 *
2739 * If the audit subsystem is being terminated, record the task (pid)
2740 * and uid that is doing that.
2741 */
audit_signal_info_syscall(struct task_struct * t)2742 int audit_signal_info_syscall(struct task_struct *t)
2743 {
2744 struct audit_aux_data_pids *axp;
2745 struct audit_context *ctx = audit_context();
2746 kuid_t t_uid = task_uid(t);
2747
2748 if (!audit_signals || audit_dummy_context())
2749 return 0;
2750
2751 /* optimize the common case by putting first signal recipient directly
2752 * in audit_context */
2753 if (!ctx->target_pid) {
2754 ctx->target_pid = task_tgid_nr(t);
2755 ctx->target_auid = audit_get_loginuid(t);
2756 ctx->target_uid = t_uid;
2757 ctx->target_sessionid = audit_get_sessionid(t);
2758 strscpy(ctx->target_comm, t->comm);
2759 security_task_getlsmprop_obj(t, &ctx->target_ref);
2760 return 0;
2761 }
2762
2763 axp = (void *)ctx->aux_pids;
2764 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2765 axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2766 if (!axp)
2767 return -ENOMEM;
2768
2769 axp->d.type = AUDIT_OBJ_PID;
2770 axp->d.next = ctx->aux_pids;
2771 ctx->aux_pids = (void *)axp;
2772 }
2773 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2774
2775 axp->target_pid[axp->pid_count] = task_tgid_nr(t);
2776 axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2777 axp->target_uid[axp->pid_count] = t_uid;
2778 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2779 security_task_getlsmprop_obj(t, &axp->target_ref[axp->pid_count]);
2780 strscpy(axp->target_comm[axp->pid_count], t->comm);
2781 axp->pid_count++;
2782
2783 return 0;
2784 }
2785
2786 /**
2787 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2788 * @bprm: pointer to the bprm being processed
2789 * @new: the proposed new credentials
2790 * @old: the old credentials
2791 *
2792 * Simply check if the proc already has the caps given by the file and if not
2793 * store the priv escalation info for later auditing at the end of the syscall
2794 *
2795 * -Eric
2796 */
__audit_log_bprm_fcaps(struct linux_binprm * bprm,const struct cred * new,const struct cred * old)2797 int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2798 const struct cred *new, const struct cred *old)
2799 {
2800 struct audit_aux_data_bprm_fcaps *ax;
2801 struct audit_context *context = audit_context();
2802 struct cpu_vfs_cap_data vcaps;
2803
2804 ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2805 if (!ax)
2806 return -ENOMEM;
2807
2808 ax->d.type = AUDIT_BPRM_FCAPS;
2809 ax->d.next = context->aux;
2810 context->aux = (void *)ax;
2811
2812 get_vfs_caps_from_disk(&nop_mnt_idmap,
2813 bprm->file->f_path.dentry, &vcaps);
2814
2815 ax->fcap.permitted = vcaps.permitted;
2816 ax->fcap.inheritable = vcaps.inheritable;
2817 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2818 ax->fcap.rootid = vcaps.rootid;
2819 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2820
2821 ax->old_pcap.permitted = old->cap_permitted;
2822 ax->old_pcap.inheritable = old->cap_inheritable;
2823 ax->old_pcap.effective = old->cap_effective;
2824 ax->old_pcap.ambient = old->cap_ambient;
2825
2826 ax->new_pcap.permitted = new->cap_permitted;
2827 ax->new_pcap.inheritable = new->cap_inheritable;
2828 ax->new_pcap.effective = new->cap_effective;
2829 ax->new_pcap.ambient = new->cap_ambient;
2830 return 0;
2831 }
2832
2833 /**
2834 * __audit_log_capset - store information about the arguments to the capset syscall
2835 * @new: the new credentials
2836 * @old: the old (current) credentials
2837 *
2838 * Record the arguments userspace sent to sys_capset for later printing by the
2839 * audit system if applicable
2840 */
__audit_log_capset(const struct cred * new,const struct cred * old)2841 void __audit_log_capset(const struct cred *new, const struct cred *old)
2842 {
2843 struct audit_context *context = audit_context();
2844
2845 context->capset.pid = task_tgid_nr(current);
2846 context->capset.cap.effective = new->cap_effective;
2847 context->capset.cap.inheritable = new->cap_effective;
2848 context->capset.cap.permitted = new->cap_permitted;
2849 context->capset.cap.ambient = new->cap_ambient;
2850 context->type = AUDIT_CAPSET;
2851 }
2852
__audit_mmap_fd(int fd,int flags)2853 void __audit_mmap_fd(int fd, int flags)
2854 {
2855 struct audit_context *context = audit_context();
2856
2857 context->mmap.fd = fd;
2858 context->mmap.flags = flags;
2859 context->type = AUDIT_MMAP;
2860 }
2861
__audit_openat2_how(struct open_how * how)2862 void __audit_openat2_how(struct open_how *how)
2863 {
2864 struct audit_context *context = audit_context();
2865
2866 context->openat2.flags = how->flags;
2867 context->openat2.mode = how->mode;
2868 context->openat2.resolve = how->resolve;
2869 context->type = AUDIT_OPENAT2;
2870 }
2871
__audit_log_kern_module(char * name)2872 void __audit_log_kern_module(char *name)
2873 {
2874 struct audit_context *context = audit_context();
2875
2876 context->module.name = kstrdup(name, GFP_KERNEL);
2877 if (!context->module.name)
2878 audit_log_lost("out of memory in __audit_log_kern_module");
2879 context->type = AUDIT_KERN_MODULE;
2880 }
2881
__audit_fanotify(u32 response,struct fanotify_response_info_audit_rule * friar)2882 void __audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar)
2883 {
2884 /* {subj,obj}_trust values are {0,1,2}: no,yes,unknown */
2885 switch (friar->hdr.type) {
2886 case FAN_RESPONSE_INFO_NONE:
2887 audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY,
2888 "resp=%u fan_type=%u fan_info=0 subj_trust=2 obj_trust=2",
2889 response, FAN_RESPONSE_INFO_NONE);
2890 break;
2891 case FAN_RESPONSE_INFO_AUDIT_RULE:
2892 audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY,
2893 "resp=%u fan_type=%u fan_info=%X subj_trust=%u obj_trust=%u",
2894 response, friar->hdr.type, friar->rule_number,
2895 friar->subj_trust, friar->obj_trust);
2896 }
2897 }
2898
__audit_tk_injoffset(struct timespec64 offset)2899 void __audit_tk_injoffset(struct timespec64 offset)
2900 {
2901 struct audit_context *context = audit_context();
2902
2903 /* only set type if not already set by NTP */
2904 if (!context->type)
2905 context->type = AUDIT_TIME_INJOFFSET;
2906 memcpy(&context->time.tk_injoffset, &offset, sizeof(offset));
2907 }
2908
__audit_ntp_log(const struct audit_ntp_data * ad)2909 void __audit_ntp_log(const struct audit_ntp_data *ad)
2910 {
2911 struct audit_context *context = audit_context();
2912 int type;
2913
2914 for (type = 0; type < AUDIT_NTP_NVALS; type++)
2915 if (ad->vals[type].newval != ad->vals[type].oldval) {
2916 /* unconditionally set type, overwriting TK */
2917 context->type = AUDIT_TIME_ADJNTPVAL;
2918 memcpy(&context->time.ntp_data, ad, sizeof(*ad));
2919 break;
2920 }
2921 }
2922
__audit_log_nfcfg(const char * name,u8 af,unsigned int nentries,enum audit_nfcfgop op,gfp_t gfp)2923 void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
2924 enum audit_nfcfgop op, gfp_t gfp)
2925 {
2926 struct audit_buffer *ab;
2927 char comm[sizeof(current->comm)];
2928
2929 ab = audit_log_start(audit_context(), gfp, AUDIT_NETFILTER_CFG);
2930 if (!ab)
2931 return;
2932 audit_log_format(ab, "table=%s family=%u entries=%u op=%s",
2933 name, af, nentries, audit_nfcfgs[op].s);
2934
2935 audit_log_format(ab, " pid=%u", task_tgid_nr(current));
2936 audit_log_task_context(ab); /* subj= */
2937 audit_log_format(ab, " comm=");
2938 audit_log_untrustedstring(ab, get_task_comm(comm, current));
2939 audit_log_end(ab);
2940 }
2941 EXPORT_SYMBOL_GPL(__audit_log_nfcfg);
2942
audit_log_task(struct audit_buffer * ab)2943 static void audit_log_task(struct audit_buffer *ab)
2944 {
2945 kuid_t auid, uid;
2946 kgid_t gid;
2947 unsigned int sessionid;
2948 char comm[sizeof(current->comm)];
2949
2950 auid = audit_get_loginuid(current);
2951 sessionid = audit_get_sessionid(current);
2952 current_uid_gid(&uid, &gid);
2953
2954 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2955 from_kuid(&init_user_ns, auid),
2956 from_kuid(&init_user_ns, uid),
2957 from_kgid(&init_user_ns, gid),
2958 sessionid);
2959 audit_log_task_context(ab);
2960 audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current));
2961 audit_log_untrustedstring(ab, get_task_comm(comm, current));
2962 audit_log_d_path_exe(ab, current->mm);
2963 }
2964
2965 /**
2966 * audit_core_dumps - record information about processes that end abnormally
2967 * @signr: signal value
2968 *
2969 * If a process ends with a core dump, something fishy is going on and we
2970 * should record the event for investigation.
2971 */
audit_core_dumps(long signr)2972 void audit_core_dumps(long signr)
2973 {
2974 struct audit_buffer *ab;
2975
2976 if (!audit_enabled)
2977 return;
2978
2979 if (signr == SIGQUIT) /* don't care for those */
2980 return;
2981
2982 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND);
2983 if (unlikely(!ab))
2984 return;
2985 audit_log_task(ab);
2986 audit_log_format(ab, " sig=%ld res=1", signr);
2987 audit_log_end(ab);
2988 }
2989
2990 /**
2991 * audit_seccomp - record information about a seccomp action
2992 * @syscall: syscall number
2993 * @signr: signal value
2994 * @code: the seccomp action
2995 *
2996 * Record the information associated with a seccomp action. Event filtering for
2997 * seccomp actions that are not to be logged is done in seccomp_log().
2998 * Therefore, this function forces auditing independent of the audit_enabled
2999 * and dummy context state because seccomp actions should be logged even when
3000 * audit is not in use.
3001 */
audit_seccomp(unsigned long syscall,long signr,int code)3002 void audit_seccomp(unsigned long syscall, long signr, int code)
3003 {
3004 struct audit_buffer *ab;
3005
3006 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP);
3007 if (unlikely(!ab))
3008 return;
3009 audit_log_task(ab);
3010 audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
3011 signr, syscall_get_arch(current), syscall,
3012 in_compat_syscall(), KSTK_EIP(current), code);
3013 audit_log_end(ab);
3014 }
3015
audit_seccomp_actions_logged(const char * names,const char * old_names,int res)3016 void audit_seccomp_actions_logged(const char *names, const char *old_names,
3017 int res)
3018 {
3019 struct audit_buffer *ab;
3020
3021 if (!audit_enabled)
3022 return;
3023
3024 ab = audit_log_start(audit_context(), GFP_KERNEL,
3025 AUDIT_CONFIG_CHANGE);
3026 if (unlikely(!ab))
3027 return;
3028
3029 audit_log_format(ab,
3030 "op=seccomp-logging actions=%s old-actions=%s res=%d",
3031 names, old_names, res);
3032 audit_log_end(ab);
3033 }
3034
audit_killed_trees(void)3035 struct list_head *audit_killed_trees(void)
3036 {
3037 struct audit_context *ctx = audit_context();
3038 if (likely(!ctx || ctx->context == AUDIT_CTX_UNUSED))
3039 return NULL;
3040 return &ctx->killed_trees;
3041 }
3042