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 struct lsm_context ctx;
1102 int rc = 0;
1103
1104 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
1105 if (!ab)
1106 return rc;
1107
1108 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
1109 from_kuid(&init_user_ns, auid),
1110 from_kuid(&init_user_ns, uid), sessionid);
1111 if (lsmprop_is_set(prop)) {
1112 if (security_lsmprop_to_secctx(prop, &ctx) < 0) {
1113 audit_log_format(ab, " obj=(none)");
1114 rc = 1;
1115 } else {
1116 audit_log_format(ab, " obj=%s", ctx.context);
1117 security_release_secctx(&ctx);
1118 }
1119 }
1120 audit_log_format(ab, " ocomm=");
1121 audit_log_untrustedstring(ab, comm);
1122 audit_log_end(ab);
1123
1124 return rc;
1125 }
1126
audit_log_execve_info(struct audit_context * context,struct audit_buffer ** ab)1127 static void audit_log_execve_info(struct audit_context *context,
1128 struct audit_buffer **ab)
1129 {
1130 long len_max;
1131 long len_rem;
1132 long len_full;
1133 long len_buf;
1134 long len_abuf = 0;
1135 long len_tmp;
1136 bool require_data;
1137 bool encode;
1138 unsigned int iter;
1139 unsigned int arg;
1140 char *buf_head;
1141 char *buf;
1142 const char __user *p = (const char __user *)current->mm->arg_start;
1143
1144 /* NOTE: this buffer needs to be large enough to hold all the non-arg
1145 * data we put in the audit record for this argument (see the
1146 * code below) ... at this point in time 96 is plenty */
1147 char abuf[96];
1148
1149 /* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the
1150 * current value of 7500 is not as important as the fact that it
1151 * is less than 8k, a setting of 7500 gives us plenty of wiggle
1152 * room if we go over a little bit in the logging below */
1153 WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500);
1154 len_max = MAX_EXECVE_AUDIT_LEN;
1155
1156 /* scratch buffer to hold the userspace args */
1157 buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1158 if (!buf_head) {
1159 audit_panic("out of memory for argv string");
1160 return;
1161 }
1162 buf = buf_head;
1163
1164 audit_log_format(*ab, "argc=%d", context->execve.argc);
1165
1166 len_rem = len_max;
1167 len_buf = 0;
1168 len_full = 0;
1169 require_data = true;
1170 encode = false;
1171 iter = 0;
1172 arg = 0;
1173 do {
1174 /* NOTE: we don't ever want to trust this value for anything
1175 * serious, but the audit record format insists we
1176 * provide an argument length for really long arguments,
1177 * e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but
1178 * to use strncpy_from_user() to obtain this value for
1179 * recording in the log, although we don't use it
1180 * anywhere here to avoid a double-fetch problem */
1181 if (len_full == 0)
1182 len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1183
1184 /* read more data from userspace */
1185 if (require_data) {
1186 /* can we make more room in the buffer? */
1187 if (buf != buf_head) {
1188 memmove(buf_head, buf, len_buf);
1189 buf = buf_head;
1190 }
1191
1192 /* fetch as much as we can of the argument */
1193 len_tmp = strncpy_from_user(&buf_head[len_buf], p,
1194 len_max - len_buf);
1195 if (len_tmp == -EFAULT) {
1196 /* unable to copy from userspace */
1197 send_sig(SIGKILL, current, 0);
1198 goto out;
1199 } else if (len_tmp == (len_max - len_buf)) {
1200 /* buffer is not large enough */
1201 require_data = true;
1202 /* NOTE: if we are going to span multiple
1203 * buffers force the encoding so we stand
1204 * a chance at a sane len_full value and
1205 * consistent record encoding */
1206 encode = true;
1207 len_full = len_full * 2;
1208 p += len_tmp;
1209 } else {
1210 require_data = false;
1211 if (!encode)
1212 encode = audit_string_contains_control(
1213 buf, len_tmp);
1214 /* try to use a trusted value for len_full */
1215 if (len_full < len_max)
1216 len_full = (encode ?
1217 len_tmp * 2 : len_tmp);
1218 p += len_tmp + 1;
1219 }
1220 len_buf += len_tmp;
1221 buf_head[len_buf] = '\0';
1222
1223 /* length of the buffer in the audit record? */
1224 len_abuf = (encode ? len_buf * 2 : len_buf + 2);
1225 }
1226
1227 /* write as much as we can to the audit log */
1228 if (len_buf >= 0) {
1229 /* NOTE: some magic numbers here - basically if we
1230 * can't fit a reasonable amount of data into the
1231 * existing audit buffer, flush it and start with
1232 * a new buffer */
1233 if ((sizeof(abuf) + 8) > len_rem) {
1234 len_rem = len_max;
1235 audit_log_end(*ab);
1236 *ab = audit_log_start(context,
1237 GFP_KERNEL, AUDIT_EXECVE);
1238 if (!*ab)
1239 goto out;
1240 }
1241
1242 /* create the non-arg portion of the arg record */
1243 len_tmp = 0;
1244 if (require_data || (iter > 0) ||
1245 ((len_abuf + sizeof(abuf)) > len_rem)) {
1246 if (iter == 0) {
1247 len_tmp += snprintf(&abuf[len_tmp],
1248 sizeof(abuf) - len_tmp,
1249 " a%d_len=%lu",
1250 arg, len_full);
1251 }
1252 len_tmp += snprintf(&abuf[len_tmp],
1253 sizeof(abuf) - len_tmp,
1254 " a%d[%d]=", arg, iter++);
1255 } else
1256 len_tmp += snprintf(&abuf[len_tmp],
1257 sizeof(abuf) - len_tmp,
1258 " a%d=", arg);
1259 WARN_ON(len_tmp >= sizeof(abuf));
1260 abuf[sizeof(abuf) - 1] = '\0';
1261
1262 /* log the arg in the audit record */
1263 audit_log_format(*ab, "%s", abuf);
1264 len_rem -= len_tmp;
1265 len_tmp = len_buf;
1266 if (encode) {
1267 if (len_abuf > len_rem)
1268 len_tmp = len_rem / 2; /* encoding */
1269 audit_log_n_hex(*ab, buf, len_tmp);
1270 len_rem -= len_tmp * 2;
1271 len_abuf -= len_tmp * 2;
1272 } else {
1273 if (len_abuf > len_rem)
1274 len_tmp = len_rem - 2; /* quotes */
1275 audit_log_n_string(*ab, buf, len_tmp);
1276 len_rem -= len_tmp + 2;
1277 /* don't subtract the "2" because we still need
1278 * to add quotes to the remaining string */
1279 len_abuf -= len_tmp;
1280 }
1281 len_buf -= len_tmp;
1282 buf += len_tmp;
1283 }
1284
1285 /* ready to move to the next argument? */
1286 if ((len_buf == 0) && !require_data) {
1287 arg++;
1288 iter = 0;
1289 len_full = 0;
1290 require_data = true;
1291 encode = false;
1292 }
1293 } while (arg < context->execve.argc);
1294
1295 /* NOTE: the caller handles the final audit_log_end() call */
1296
1297 out:
1298 kfree(buf_head);
1299 }
1300
audit_log_cap(struct audit_buffer * ab,char * prefix,kernel_cap_t * cap)1301 static void audit_log_cap(struct audit_buffer *ab, char *prefix,
1302 kernel_cap_t *cap)
1303 {
1304 if (cap_isclear(*cap)) {
1305 audit_log_format(ab, " %s=0", prefix);
1306 return;
1307 }
1308 audit_log_format(ab, " %s=%016llx", prefix, cap->val);
1309 }
1310
audit_log_fcaps(struct audit_buffer * ab,struct audit_names * name)1311 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1312 {
1313 if (name->fcap_ver == -1) {
1314 audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?");
1315 return;
1316 }
1317 audit_log_cap(ab, "cap_fp", &name->fcap.permitted);
1318 audit_log_cap(ab, "cap_fi", &name->fcap.inheritable);
1319 audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d",
1320 name->fcap.fE, name->fcap_ver,
1321 from_kuid(&init_user_ns, name->fcap.rootid));
1322 }
1323
audit_log_time(struct audit_context * context,struct audit_buffer ** ab)1324 static void audit_log_time(struct audit_context *context, struct audit_buffer **ab)
1325 {
1326 const struct audit_ntp_data *ntp = &context->time.ntp_data;
1327 const struct timespec64 *tk = &context->time.tk_injoffset;
1328 static const char * const ntp_name[] = {
1329 "offset",
1330 "freq",
1331 "status",
1332 "tai",
1333 "tick",
1334 "adjust",
1335 };
1336 int type;
1337
1338 if (context->type == AUDIT_TIME_ADJNTPVAL) {
1339 for (type = 0; type < AUDIT_NTP_NVALS; type++) {
1340 if (ntp->vals[type].newval != ntp->vals[type].oldval) {
1341 if (!*ab) {
1342 *ab = audit_log_start(context,
1343 GFP_KERNEL,
1344 AUDIT_TIME_ADJNTPVAL);
1345 if (!*ab)
1346 return;
1347 }
1348 audit_log_format(*ab, "op=%s old=%lli new=%lli",
1349 ntp_name[type],
1350 ntp->vals[type].oldval,
1351 ntp->vals[type].newval);
1352 audit_log_end(*ab);
1353 *ab = NULL;
1354 }
1355 }
1356 }
1357 if (tk->tv_sec != 0 || tk->tv_nsec != 0) {
1358 if (!*ab) {
1359 *ab = audit_log_start(context, GFP_KERNEL,
1360 AUDIT_TIME_INJOFFSET);
1361 if (!*ab)
1362 return;
1363 }
1364 audit_log_format(*ab, "sec=%lli nsec=%li",
1365 (long long)tk->tv_sec, tk->tv_nsec);
1366 audit_log_end(*ab);
1367 *ab = NULL;
1368 }
1369 }
1370
show_special(struct audit_context * context,int * call_panic)1371 static void show_special(struct audit_context *context, int *call_panic)
1372 {
1373 struct audit_buffer *ab;
1374 int i;
1375
1376 ab = audit_log_start(context, GFP_KERNEL, context->type);
1377 if (!ab)
1378 return;
1379
1380 switch (context->type) {
1381 case AUDIT_SOCKETCALL: {
1382 int nargs = context->socketcall.nargs;
1383
1384 audit_log_format(ab, "nargs=%d", nargs);
1385 for (i = 0; i < nargs; i++)
1386 audit_log_format(ab, " a%d=%lx", i,
1387 context->socketcall.args[i]);
1388 break; }
1389 case AUDIT_IPC:
1390 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1391 from_kuid(&init_user_ns, context->ipc.uid),
1392 from_kgid(&init_user_ns, context->ipc.gid),
1393 context->ipc.mode);
1394 if (lsmprop_is_set(&context->ipc.oprop)) {
1395 struct lsm_context lsmctx;
1396
1397 if (security_lsmprop_to_secctx(&context->ipc.oprop,
1398 &lsmctx) < 0) {
1399 *call_panic = 1;
1400 } else {
1401 audit_log_format(ab, " obj=%s", lsmctx.context);
1402 security_release_secctx(&lsmctx);
1403 }
1404 }
1405 if (context->ipc.has_perm) {
1406 audit_log_end(ab);
1407 ab = audit_log_start(context, GFP_KERNEL,
1408 AUDIT_IPC_SET_PERM);
1409 if (unlikely(!ab))
1410 return;
1411 audit_log_format(ab,
1412 "qbytes=%lx ouid=%u ogid=%u mode=%#ho",
1413 context->ipc.qbytes,
1414 context->ipc.perm_uid,
1415 context->ipc.perm_gid,
1416 context->ipc.perm_mode);
1417 }
1418 break;
1419 case AUDIT_MQ_OPEN:
1420 audit_log_format(ab,
1421 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
1422 "mq_msgsize=%ld mq_curmsgs=%ld",
1423 context->mq_open.oflag, context->mq_open.mode,
1424 context->mq_open.attr.mq_flags,
1425 context->mq_open.attr.mq_maxmsg,
1426 context->mq_open.attr.mq_msgsize,
1427 context->mq_open.attr.mq_curmsgs);
1428 break;
1429 case AUDIT_MQ_SENDRECV:
1430 audit_log_format(ab,
1431 "mqdes=%d msg_len=%zd msg_prio=%u "
1432 "abs_timeout_sec=%lld abs_timeout_nsec=%ld",
1433 context->mq_sendrecv.mqdes,
1434 context->mq_sendrecv.msg_len,
1435 context->mq_sendrecv.msg_prio,
1436 (long long) context->mq_sendrecv.abs_timeout.tv_sec,
1437 context->mq_sendrecv.abs_timeout.tv_nsec);
1438 break;
1439 case AUDIT_MQ_NOTIFY:
1440 audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1441 context->mq_notify.mqdes,
1442 context->mq_notify.sigev_signo);
1443 break;
1444 case AUDIT_MQ_GETSETATTR: {
1445 struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1446
1447 audit_log_format(ab,
1448 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1449 "mq_curmsgs=%ld ",
1450 context->mq_getsetattr.mqdes,
1451 attr->mq_flags, attr->mq_maxmsg,
1452 attr->mq_msgsize, attr->mq_curmsgs);
1453 break; }
1454 case AUDIT_CAPSET:
1455 audit_log_format(ab, "pid=%d", context->capset.pid);
1456 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1457 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1458 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1459 audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient);
1460 break;
1461 case AUDIT_MMAP:
1462 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
1463 context->mmap.flags);
1464 break;
1465 case AUDIT_OPENAT2:
1466 audit_log_format(ab, "oflag=0%llo mode=0%llo resolve=0x%llx",
1467 context->openat2.flags,
1468 context->openat2.mode,
1469 context->openat2.resolve);
1470 break;
1471 case AUDIT_EXECVE:
1472 audit_log_execve_info(context, &ab);
1473 break;
1474 case AUDIT_KERN_MODULE:
1475 audit_log_format(ab, "name=");
1476 if (context->module.name) {
1477 audit_log_untrustedstring(ab, context->module.name);
1478 } else
1479 audit_log_format(ab, "(null)");
1480
1481 break;
1482 case AUDIT_TIME_ADJNTPVAL:
1483 case AUDIT_TIME_INJOFFSET:
1484 /* this call deviates from the rest, eating the buffer */
1485 audit_log_time(context, &ab);
1486 break;
1487 }
1488 audit_log_end(ab);
1489 }
1490
audit_proctitle_rtrim(char * proctitle,int len)1491 static inline int audit_proctitle_rtrim(char *proctitle, int len)
1492 {
1493 char *end = proctitle + len - 1;
1494
1495 while (end > proctitle && !isprint(*end))
1496 end--;
1497
1498 /* catch the case where proctitle is only 1 non-print character */
1499 len = end - proctitle + 1;
1500 len -= isprint(proctitle[len-1]) == 0;
1501 return len;
1502 }
1503
1504 /*
1505 * audit_log_name - produce AUDIT_PATH record from struct audit_names
1506 * @context: audit_context for the task
1507 * @n: audit_names structure with reportable details
1508 * @path: optional path to report instead of audit_names->name
1509 * @record_num: record number to report when handling a list of names
1510 * @call_panic: optional pointer to int that will be updated if secid fails
1511 */
audit_log_name(struct audit_context * context,struct audit_names * n,const struct path * path,int record_num,int * call_panic)1512 static void audit_log_name(struct audit_context *context, struct audit_names *n,
1513 const struct path *path, int record_num, int *call_panic)
1514 {
1515 struct audit_buffer *ab;
1516
1517 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1518 if (!ab)
1519 return;
1520
1521 audit_log_format(ab, "item=%d", record_num);
1522
1523 if (path)
1524 audit_log_d_path(ab, " name=", path);
1525 else if (n->name) {
1526 switch (n->name_len) {
1527 case AUDIT_NAME_FULL:
1528 /* log the full path */
1529 audit_log_format(ab, " name=");
1530 audit_log_untrustedstring(ab, n->name->name);
1531 break;
1532 case 0:
1533 /* name was specified as a relative path and the
1534 * directory component is the cwd
1535 */
1536 if (context->pwd.dentry && context->pwd.mnt)
1537 audit_log_d_path(ab, " name=", &context->pwd);
1538 else
1539 audit_log_format(ab, " name=(null)");
1540 break;
1541 default:
1542 /* log the name's directory component */
1543 audit_log_format(ab, " name=");
1544 audit_log_n_untrustedstring(ab, n->name->name,
1545 n->name_len);
1546 }
1547 } else
1548 audit_log_format(ab, " name=(null)");
1549
1550 if (n->ino != AUDIT_INO_UNSET)
1551 audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#ho ouid=%u ogid=%u rdev=%02x:%02x",
1552 n->ino,
1553 MAJOR(n->dev),
1554 MINOR(n->dev),
1555 n->mode,
1556 from_kuid(&init_user_ns, n->uid),
1557 from_kgid(&init_user_ns, n->gid),
1558 MAJOR(n->rdev),
1559 MINOR(n->rdev));
1560 if (lsmprop_is_set(&n->oprop)) {
1561 struct lsm_context ctx;
1562
1563 if (security_lsmprop_to_secctx(&n->oprop, &ctx) < 0) {
1564 if (call_panic)
1565 *call_panic = 2;
1566 } else {
1567 audit_log_format(ab, " obj=%s", ctx.context);
1568 security_release_secctx(&ctx);
1569 }
1570 }
1571
1572 /* log the audit_names record type */
1573 switch (n->type) {
1574 case AUDIT_TYPE_NORMAL:
1575 audit_log_format(ab, " nametype=NORMAL");
1576 break;
1577 case AUDIT_TYPE_PARENT:
1578 audit_log_format(ab, " nametype=PARENT");
1579 break;
1580 case AUDIT_TYPE_CHILD_DELETE:
1581 audit_log_format(ab, " nametype=DELETE");
1582 break;
1583 case AUDIT_TYPE_CHILD_CREATE:
1584 audit_log_format(ab, " nametype=CREATE");
1585 break;
1586 default:
1587 audit_log_format(ab, " nametype=UNKNOWN");
1588 break;
1589 }
1590
1591 audit_log_fcaps(ab, n);
1592 audit_log_end(ab);
1593 }
1594
audit_log_proctitle(void)1595 static void audit_log_proctitle(void)
1596 {
1597 int res;
1598 char *buf;
1599 char *msg = "(null)";
1600 int len = strlen(msg);
1601 struct audit_context *context = audit_context();
1602 struct audit_buffer *ab;
1603
1604 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE);
1605 if (!ab)
1606 return; /* audit_panic or being filtered */
1607
1608 audit_log_format(ab, "proctitle=");
1609
1610 /* Not cached */
1611 if (!context->proctitle.value) {
1612 buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL);
1613 if (!buf)
1614 goto out;
1615 /* Historically called this from procfs naming */
1616 res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN);
1617 if (res == 0) {
1618 kfree(buf);
1619 goto out;
1620 }
1621 res = audit_proctitle_rtrim(buf, res);
1622 if (res == 0) {
1623 kfree(buf);
1624 goto out;
1625 }
1626 context->proctitle.value = buf;
1627 context->proctitle.len = res;
1628 }
1629 msg = context->proctitle.value;
1630 len = context->proctitle.len;
1631 out:
1632 audit_log_n_untrustedstring(ab, msg, len);
1633 audit_log_end(ab);
1634 }
1635
1636 /**
1637 * audit_log_uring - generate a AUDIT_URINGOP record
1638 * @ctx: the audit context
1639 */
audit_log_uring(struct audit_context * ctx)1640 static void audit_log_uring(struct audit_context *ctx)
1641 {
1642 struct audit_buffer *ab;
1643 const struct cred *cred;
1644
1645 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_URINGOP);
1646 if (!ab)
1647 return;
1648 cred = current_cred();
1649 audit_log_format(ab, "uring_op=%d", ctx->uring_op);
1650 if (ctx->return_valid != AUDITSC_INVALID)
1651 audit_log_format(ab, " success=%s exit=%ld",
1652 str_yes_no(ctx->return_valid ==
1653 AUDITSC_SUCCESS),
1654 ctx->return_code);
1655 audit_log_format(ab,
1656 " items=%d"
1657 " ppid=%d pid=%d uid=%u gid=%u euid=%u suid=%u"
1658 " fsuid=%u egid=%u sgid=%u fsgid=%u",
1659 ctx->name_count,
1660 task_ppid_nr(current), task_tgid_nr(current),
1661 from_kuid(&init_user_ns, cred->uid),
1662 from_kgid(&init_user_ns, cred->gid),
1663 from_kuid(&init_user_ns, cred->euid),
1664 from_kuid(&init_user_ns, cred->suid),
1665 from_kuid(&init_user_ns, cred->fsuid),
1666 from_kgid(&init_user_ns, cred->egid),
1667 from_kgid(&init_user_ns, cred->sgid),
1668 from_kgid(&init_user_ns, cred->fsgid));
1669 audit_log_task_context(ab);
1670 audit_log_key(ab, ctx->filterkey);
1671 audit_log_end(ab);
1672 }
1673
audit_log_exit(void)1674 static void audit_log_exit(void)
1675 {
1676 int i, call_panic = 0;
1677 struct audit_context *context = audit_context();
1678 struct audit_buffer *ab;
1679 struct audit_aux_data *aux;
1680 struct audit_names *n;
1681
1682 context->personality = current->personality;
1683
1684 switch (context->context) {
1685 case AUDIT_CTX_SYSCALL:
1686 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1687 if (!ab)
1688 return;
1689 audit_log_format(ab, "arch=%x syscall=%d",
1690 context->arch, context->major);
1691 if (context->personality != PER_LINUX)
1692 audit_log_format(ab, " per=%lx", context->personality);
1693 if (context->return_valid != AUDITSC_INVALID)
1694 audit_log_format(ab, " success=%s exit=%ld",
1695 str_yes_no(context->return_valid ==
1696 AUDITSC_SUCCESS),
1697 context->return_code);
1698 audit_log_format(ab,
1699 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d",
1700 context->argv[0],
1701 context->argv[1],
1702 context->argv[2],
1703 context->argv[3],
1704 context->name_count);
1705 audit_log_task_info(ab);
1706 audit_log_key(ab, context->filterkey);
1707 audit_log_end(ab);
1708 break;
1709 case AUDIT_CTX_URING:
1710 audit_log_uring(context);
1711 break;
1712 default:
1713 BUG();
1714 break;
1715 }
1716
1717 for (aux = context->aux; aux; aux = aux->next) {
1718
1719 ab = audit_log_start(context, GFP_KERNEL, aux->type);
1720 if (!ab)
1721 continue; /* audit_panic has been called */
1722
1723 switch (aux->type) {
1724
1725 case AUDIT_BPRM_FCAPS: {
1726 struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1727
1728 audit_log_format(ab, "fver=%x", axs->fcap_ver);
1729 audit_log_cap(ab, "fp", &axs->fcap.permitted);
1730 audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1731 audit_log_format(ab, " fe=%d", axs->fcap.fE);
1732 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1733 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1734 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1735 audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient);
1736 audit_log_cap(ab, "pp", &axs->new_pcap.permitted);
1737 audit_log_cap(ab, "pi", &axs->new_pcap.inheritable);
1738 audit_log_cap(ab, "pe", &axs->new_pcap.effective);
1739 audit_log_cap(ab, "pa", &axs->new_pcap.ambient);
1740 audit_log_format(ab, " frootid=%d",
1741 from_kuid(&init_user_ns,
1742 axs->fcap.rootid));
1743 break; }
1744
1745 }
1746 audit_log_end(ab);
1747 }
1748
1749 if (context->type)
1750 show_special(context, &call_panic);
1751
1752 if (context->fds[0] >= 0) {
1753 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1754 if (ab) {
1755 audit_log_format(ab, "fd0=%d fd1=%d",
1756 context->fds[0], context->fds[1]);
1757 audit_log_end(ab);
1758 }
1759 }
1760
1761 if (context->sockaddr_len) {
1762 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1763 if (ab) {
1764 audit_log_format(ab, "saddr=");
1765 audit_log_n_hex(ab, (void *)context->sockaddr,
1766 context->sockaddr_len);
1767 audit_log_end(ab);
1768 }
1769 }
1770
1771 for (aux = context->aux_pids; aux; aux = aux->next) {
1772 struct audit_aux_data_pids *axs = (void *)aux;
1773
1774 for (i = 0; i < axs->pid_count; i++)
1775 if (audit_log_pid_context(context, axs->target_pid[i],
1776 axs->target_auid[i],
1777 axs->target_uid[i],
1778 axs->target_sessionid[i],
1779 &axs->target_ref[i],
1780 axs->target_comm[i]))
1781 call_panic = 1;
1782 }
1783
1784 if (context->target_pid &&
1785 audit_log_pid_context(context, context->target_pid,
1786 context->target_auid, context->target_uid,
1787 context->target_sessionid,
1788 &context->target_ref, context->target_comm))
1789 call_panic = 1;
1790
1791 if (context->pwd.dentry && context->pwd.mnt) {
1792 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1793 if (ab) {
1794 audit_log_d_path(ab, "cwd=", &context->pwd);
1795 audit_log_end(ab);
1796 }
1797 }
1798
1799 i = 0;
1800 list_for_each_entry(n, &context->names_list, list) {
1801 if (n->hidden)
1802 continue;
1803 audit_log_name(context, n, NULL, i++, &call_panic);
1804 }
1805
1806 if (context->context == AUDIT_CTX_SYSCALL)
1807 audit_log_proctitle();
1808
1809 /* Send end of event record to help user space know we are finished */
1810 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1811 if (ab)
1812 audit_log_end(ab);
1813 if (call_panic)
1814 audit_panic("error in audit_log_exit()");
1815 }
1816
1817 /**
1818 * __audit_free - free a per-task audit context
1819 * @tsk: task whose audit context block to free
1820 *
1821 * Called from copy_process, do_exit, and the io_uring code
1822 */
__audit_free(struct task_struct * tsk)1823 void __audit_free(struct task_struct *tsk)
1824 {
1825 struct audit_context *context = tsk->audit_context;
1826
1827 if (!context)
1828 return;
1829
1830 /* this may generate CONFIG_CHANGE records */
1831 if (!list_empty(&context->killed_trees))
1832 audit_kill_trees(context);
1833
1834 /* We are called either by do_exit() or the fork() error handling code;
1835 * in the former case tsk == current and in the latter tsk is a
1836 * random task_struct that doesn't have any meaningful data we
1837 * need to log via audit_log_exit().
1838 */
1839 if (tsk == current && !context->dummy) {
1840 context->return_valid = AUDITSC_INVALID;
1841 context->return_code = 0;
1842 if (context->context == AUDIT_CTX_SYSCALL) {
1843 audit_filter_syscall(tsk, context);
1844 audit_filter_inodes(tsk, context);
1845 if (context->current_state == AUDIT_STATE_RECORD)
1846 audit_log_exit();
1847 } else if (context->context == AUDIT_CTX_URING) {
1848 /* TODO: verify this case is real and valid */
1849 audit_filter_uring(tsk, context);
1850 audit_filter_inodes(tsk, context);
1851 if (context->current_state == AUDIT_STATE_RECORD)
1852 audit_log_uring(context);
1853 }
1854 }
1855
1856 audit_set_context(tsk, NULL);
1857 audit_free_context(context);
1858 }
1859
1860 /**
1861 * audit_return_fixup - fixup the return codes in the audit_context
1862 * @ctx: the audit_context
1863 * @success: true/false value to indicate if the operation succeeded or not
1864 * @code: operation return code
1865 *
1866 * We need to fixup the return code in the audit logs if the actual return
1867 * codes are later going to be fixed by the arch specific signal handlers.
1868 */
audit_return_fixup(struct audit_context * ctx,int success,long code)1869 static void audit_return_fixup(struct audit_context *ctx,
1870 int success, long code)
1871 {
1872 /*
1873 * This is actually a test for:
1874 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
1875 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
1876 *
1877 * but is faster than a bunch of ||
1878 */
1879 if (unlikely(code <= -ERESTARTSYS) &&
1880 (code >= -ERESTART_RESTARTBLOCK) &&
1881 (code != -ENOIOCTLCMD))
1882 ctx->return_code = -EINTR;
1883 else
1884 ctx->return_code = code;
1885 ctx->return_valid = (success ? AUDITSC_SUCCESS : AUDITSC_FAILURE);
1886 }
1887
1888 /**
1889 * __audit_uring_entry - prepare the kernel task's audit context for io_uring
1890 * @op: the io_uring opcode
1891 *
1892 * This is similar to audit_syscall_entry() but is intended for use by io_uring
1893 * operations. This function should only ever be called from
1894 * audit_uring_entry() as we rely on the audit context checking present in that
1895 * function.
1896 */
__audit_uring_entry(u8 op)1897 void __audit_uring_entry(u8 op)
1898 {
1899 struct audit_context *ctx = audit_context();
1900
1901 if (ctx->state == AUDIT_STATE_DISABLED)
1902 return;
1903
1904 /*
1905 * NOTE: It's possible that we can be called from the process' context
1906 * before it returns to userspace, and before audit_syscall_exit()
1907 * is called. In this case there is not much to do, just record
1908 * the io_uring details and return.
1909 */
1910 ctx->uring_op = op;
1911 if (ctx->context == AUDIT_CTX_SYSCALL)
1912 return;
1913
1914 ctx->dummy = !audit_n_rules;
1915 if (!ctx->dummy && ctx->state == AUDIT_STATE_BUILD)
1916 ctx->prio = 0;
1917
1918 ctx->context = AUDIT_CTX_URING;
1919 ctx->current_state = ctx->state;
1920 ktime_get_coarse_real_ts64(&ctx->ctime);
1921 }
1922
1923 /**
1924 * __audit_uring_exit - wrap up the kernel task's audit context after io_uring
1925 * @success: true/false value to indicate if the operation succeeded or not
1926 * @code: operation return code
1927 *
1928 * This is similar to audit_syscall_exit() but is intended for use by io_uring
1929 * operations. This function should only ever be called from
1930 * audit_uring_exit() as we rely on the audit context checking present in that
1931 * function.
1932 */
__audit_uring_exit(int success,long code)1933 void __audit_uring_exit(int success, long code)
1934 {
1935 struct audit_context *ctx = audit_context();
1936
1937 if (ctx->dummy) {
1938 if (ctx->context != AUDIT_CTX_URING)
1939 return;
1940 goto out;
1941 }
1942
1943 audit_return_fixup(ctx, success, code);
1944 if (ctx->context == AUDIT_CTX_SYSCALL) {
1945 /*
1946 * NOTE: See the note in __audit_uring_entry() about the case
1947 * where we may be called from process context before we
1948 * return to userspace via audit_syscall_exit(). In this
1949 * case we simply emit a URINGOP record and bail, the
1950 * normal syscall exit handling will take care of
1951 * everything else.
1952 * It is also worth mentioning that when we are called,
1953 * the current process creds may differ from the creds
1954 * used during the normal syscall processing; keep that
1955 * in mind if/when we move the record generation code.
1956 */
1957
1958 /*
1959 * We need to filter on the syscall info here to decide if we
1960 * should emit a URINGOP record. I know it seems odd but this
1961 * solves the problem where users have a filter to block *all*
1962 * syscall records in the "exit" filter; we want to preserve
1963 * the behavior here.
1964 */
1965 audit_filter_syscall(current, ctx);
1966 if (ctx->current_state != AUDIT_STATE_RECORD)
1967 audit_filter_uring(current, ctx);
1968 audit_filter_inodes(current, ctx);
1969 if (ctx->current_state != AUDIT_STATE_RECORD)
1970 return;
1971
1972 audit_log_uring(ctx);
1973 return;
1974 }
1975
1976 /* this may generate CONFIG_CHANGE records */
1977 if (!list_empty(&ctx->killed_trees))
1978 audit_kill_trees(ctx);
1979
1980 /* run through both filters to ensure we set the filterkey properly */
1981 audit_filter_uring(current, ctx);
1982 audit_filter_inodes(current, ctx);
1983 if (ctx->current_state != AUDIT_STATE_RECORD)
1984 goto out;
1985 audit_log_exit();
1986
1987 out:
1988 audit_reset_context(ctx);
1989 }
1990
1991 /**
1992 * __audit_syscall_entry - fill in an audit record at syscall entry
1993 * @major: major syscall type (function)
1994 * @a1: additional syscall register 1
1995 * @a2: additional syscall register 2
1996 * @a3: additional syscall register 3
1997 * @a4: additional syscall register 4
1998 *
1999 * Fill in audit context at syscall entry. This only happens if the
2000 * audit context was created when the task was created and the state or
2001 * filters demand the audit context be built. If the state from the
2002 * per-task filter or from the per-syscall filter is AUDIT_STATE_RECORD,
2003 * then the record will be written at syscall exit time (otherwise, it
2004 * will only be written if another part of the kernel requests that it
2005 * be written).
2006 */
__audit_syscall_entry(int major,unsigned long a1,unsigned long a2,unsigned long a3,unsigned long a4)2007 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
2008 unsigned long a3, unsigned long a4)
2009 {
2010 struct audit_context *context = audit_context();
2011 enum audit_state state;
2012
2013 if (!audit_enabled || !context)
2014 return;
2015
2016 WARN_ON(context->context != AUDIT_CTX_UNUSED);
2017 WARN_ON(context->name_count);
2018 if (context->context != AUDIT_CTX_UNUSED || context->name_count) {
2019 audit_panic("unrecoverable error in audit_syscall_entry()");
2020 return;
2021 }
2022
2023 state = context->state;
2024 if (state == AUDIT_STATE_DISABLED)
2025 return;
2026
2027 context->dummy = !audit_n_rules;
2028 if (!context->dummy && state == AUDIT_STATE_BUILD) {
2029 context->prio = 0;
2030 if (auditd_test_task(current))
2031 return;
2032 }
2033
2034 context->arch = syscall_get_arch(current);
2035 context->major = major;
2036 context->argv[0] = a1;
2037 context->argv[1] = a2;
2038 context->argv[2] = a3;
2039 context->argv[3] = a4;
2040 context->context = AUDIT_CTX_SYSCALL;
2041 context->current_state = state;
2042 ktime_get_coarse_real_ts64(&context->ctime);
2043 }
2044
2045 /**
2046 * __audit_syscall_exit - deallocate audit context after a system call
2047 * @success: success value of the syscall
2048 * @return_code: return value of the syscall
2049 *
2050 * Tear down after system call. If the audit context has been marked as
2051 * auditable (either because of the AUDIT_STATE_RECORD state from
2052 * filtering, or because some other part of the kernel wrote an audit
2053 * message), then write out the syscall information. In call cases,
2054 * free the names stored from getname().
2055 */
__audit_syscall_exit(int success,long return_code)2056 void __audit_syscall_exit(int success, long return_code)
2057 {
2058 struct audit_context *context = audit_context();
2059
2060 if (!context || context->dummy ||
2061 context->context != AUDIT_CTX_SYSCALL)
2062 goto out;
2063
2064 /* this may generate CONFIG_CHANGE records */
2065 if (!list_empty(&context->killed_trees))
2066 audit_kill_trees(context);
2067
2068 audit_return_fixup(context, success, return_code);
2069 /* run through both filters to ensure we set the filterkey properly */
2070 audit_filter_syscall(current, context);
2071 audit_filter_inodes(current, context);
2072 if (context->current_state != AUDIT_STATE_RECORD)
2073 goto out;
2074
2075 audit_log_exit();
2076
2077 out:
2078 audit_reset_context(context);
2079 }
2080
handle_one(const struct inode * inode)2081 static inline void handle_one(const struct inode *inode)
2082 {
2083 struct audit_context *context;
2084 struct audit_tree_refs *p;
2085 struct audit_chunk *chunk;
2086 int count;
2087
2088 if (likely(!inode->i_fsnotify_marks))
2089 return;
2090 context = audit_context();
2091 p = context->trees;
2092 count = context->tree_count;
2093 rcu_read_lock();
2094 chunk = audit_tree_lookup(inode);
2095 rcu_read_unlock();
2096 if (!chunk)
2097 return;
2098 if (likely(put_tree_ref(context, chunk)))
2099 return;
2100 if (unlikely(!grow_tree_refs(context))) {
2101 pr_warn("out of memory, audit has lost a tree reference\n");
2102 audit_set_auditable(context);
2103 audit_put_chunk(chunk);
2104 unroll_tree_refs(context, p, count);
2105 return;
2106 }
2107 put_tree_ref(context, chunk);
2108 }
2109
handle_path(const struct dentry * dentry)2110 static void handle_path(const struct dentry *dentry)
2111 {
2112 struct audit_context *context;
2113 struct audit_tree_refs *p;
2114 const struct dentry *d, *parent;
2115 struct audit_chunk *drop;
2116 unsigned long seq;
2117 int count;
2118
2119 context = audit_context();
2120 p = context->trees;
2121 count = context->tree_count;
2122 retry:
2123 drop = NULL;
2124 d = dentry;
2125 rcu_read_lock();
2126 seq = read_seqbegin(&rename_lock);
2127 for (;;) {
2128 struct inode *inode = d_backing_inode(d);
2129
2130 if (inode && unlikely(inode->i_fsnotify_marks)) {
2131 struct audit_chunk *chunk;
2132
2133 chunk = audit_tree_lookup(inode);
2134 if (chunk) {
2135 if (unlikely(!put_tree_ref(context, chunk))) {
2136 drop = chunk;
2137 break;
2138 }
2139 }
2140 }
2141 parent = d->d_parent;
2142 if (parent == d)
2143 break;
2144 d = parent;
2145 }
2146 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */
2147 rcu_read_unlock();
2148 if (!drop) {
2149 /* just a race with rename */
2150 unroll_tree_refs(context, p, count);
2151 goto retry;
2152 }
2153 audit_put_chunk(drop);
2154 if (grow_tree_refs(context)) {
2155 /* OK, got more space */
2156 unroll_tree_refs(context, p, count);
2157 goto retry;
2158 }
2159 /* too bad */
2160 pr_warn("out of memory, audit has lost a tree reference\n");
2161 unroll_tree_refs(context, p, count);
2162 audit_set_auditable(context);
2163 return;
2164 }
2165 rcu_read_unlock();
2166 }
2167
audit_alloc_name(struct audit_context * context,unsigned char type)2168 static struct audit_names *audit_alloc_name(struct audit_context *context,
2169 unsigned char type)
2170 {
2171 struct audit_names *aname;
2172
2173 if (context->name_count < AUDIT_NAMES) {
2174 aname = &context->preallocated_names[context->name_count];
2175 memset(aname, 0, sizeof(*aname));
2176 } else {
2177 aname = kzalloc(sizeof(*aname), GFP_NOFS);
2178 if (!aname)
2179 return NULL;
2180 aname->should_free = true;
2181 }
2182
2183 aname->ino = AUDIT_INO_UNSET;
2184 aname->type = type;
2185 list_add_tail(&aname->list, &context->names_list);
2186
2187 context->name_count++;
2188 if (!context->pwd.dentry)
2189 get_fs_pwd(current->fs, &context->pwd);
2190 return aname;
2191 }
2192
2193 /**
2194 * __audit_reusename - fill out filename with info from existing entry
2195 * @uptr: userland ptr to pathname
2196 *
2197 * Search the audit_names list for the current audit context. If there is an
2198 * existing entry with a matching "uptr" then return the filename
2199 * associated with that audit_name. If not, return NULL.
2200 */
2201 struct filename *
__audit_reusename(const __user char * uptr)2202 __audit_reusename(const __user char *uptr)
2203 {
2204 struct audit_context *context = audit_context();
2205 struct audit_names *n;
2206
2207 list_for_each_entry(n, &context->names_list, list) {
2208 if (!n->name)
2209 continue;
2210 if (n->name->uptr == uptr) {
2211 atomic_inc(&n->name->refcnt);
2212 return n->name;
2213 }
2214 }
2215 return NULL;
2216 }
2217
2218 /**
2219 * __audit_getname - add a name to the list
2220 * @name: name to add
2221 *
2222 * Add a name to the list of audit names for this context.
2223 * Called from fs/namei.c:getname().
2224 */
__audit_getname(struct filename * name)2225 void __audit_getname(struct filename *name)
2226 {
2227 struct audit_context *context = audit_context();
2228 struct audit_names *n;
2229
2230 if (context->context == AUDIT_CTX_UNUSED)
2231 return;
2232
2233 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2234 if (!n)
2235 return;
2236
2237 n->name = name;
2238 n->name_len = AUDIT_NAME_FULL;
2239 name->aname = n;
2240 atomic_inc(&name->refcnt);
2241 }
2242
audit_copy_fcaps(struct audit_names * name,const struct dentry * dentry)2243 static inline int audit_copy_fcaps(struct audit_names *name,
2244 const struct dentry *dentry)
2245 {
2246 struct cpu_vfs_cap_data caps;
2247 int rc;
2248
2249 if (!dentry)
2250 return 0;
2251
2252 rc = get_vfs_caps_from_disk(&nop_mnt_idmap, dentry, &caps);
2253 if (rc)
2254 return rc;
2255
2256 name->fcap.permitted = caps.permitted;
2257 name->fcap.inheritable = caps.inheritable;
2258 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2259 name->fcap.rootid = caps.rootid;
2260 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >>
2261 VFS_CAP_REVISION_SHIFT;
2262
2263 return 0;
2264 }
2265
2266 /* Copy inode data into an audit_names. */
audit_copy_inode(struct audit_names * name,const struct dentry * dentry,struct inode * inode,unsigned int flags)2267 static void audit_copy_inode(struct audit_names *name,
2268 const struct dentry *dentry,
2269 struct inode *inode, unsigned int flags)
2270 {
2271 name->ino = inode->i_ino;
2272 name->dev = inode->i_sb->s_dev;
2273 name->mode = inode->i_mode;
2274 name->uid = inode->i_uid;
2275 name->gid = inode->i_gid;
2276 name->rdev = inode->i_rdev;
2277 security_inode_getlsmprop(inode, &name->oprop);
2278 if (flags & AUDIT_INODE_NOEVAL) {
2279 name->fcap_ver = -1;
2280 return;
2281 }
2282 audit_copy_fcaps(name, dentry);
2283 }
2284
2285 /**
2286 * __audit_inode - store the inode and device from a lookup
2287 * @name: name being audited
2288 * @dentry: dentry being audited
2289 * @flags: attributes for this particular entry
2290 */
__audit_inode(struct filename * name,const struct dentry * dentry,unsigned int flags)2291 void __audit_inode(struct filename *name, const struct dentry *dentry,
2292 unsigned int flags)
2293 {
2294 struct audit_context *context = audit_context();
2295 struct inode *inode = d_backing_inode(dentry);
2296 struct audit_names *n;
2297 bool parent = flags & AUDIT_INODE_PARENT;
2298 struct audit_entry *e;
2299 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
2300 int i;
2301
2302 if (context->context == AUDIT_CTX_UNUSED)
2303 return;
2304
2305 rcu_read_lock();
2306 list_for_each_entry_rcu(e, list, list) {
2307 for (i = 0; i < e->rule.field_count; i++) {
2308 struct audit_field *f = &e->rule.fields[i];
2309
2310 if (f->type == AUDIT_FSTYPE
2311 && audit_comparator(inode->i_sb->s_magic,
2312 f->op, f->val)
2313 && e->rule.action == AUDIT_NEVER) {
2314 rcu_read_unlock();
2315 return;
2316 }
2317 }
2318 }
2319 rcu_read_unlock();
2320
2321 if (!name)
2322 goto out_alloc;
2323
2324 /*
2325 * If we have a pointer to an audit_names entry already, then we can
2326 * just use it directly if the type is correct.
2327 */
2328 n = name->aname;
2329 if (n) {
2330 if (parent) {
2331 if (n->type == AUDIT_TYPE_PARENT ||
2332 n->type == AUDIT_TYPE_UNKNOWN)
2333 goto out;
2334 } else {
2335 if (n->type != AUDIT_TYPE_PARENT)
2336 goto out;
2337 }
2338 }
2339
2340 list_for_each_entry_reverse(n, &context->names_list, list) {
2341 if (n->ino) {
2342 /* valid inode number, use that for the comparison */
2343 if (n->ino != inode->i_ino ||
2344 n->dev != inode->i_sb->s_dev)
2345 continue;
2346 } else if (n->name) {
2347 /* inode number has not been set, check the name */
2348 if (strcmp(n->name->name, name->name))
2349 continue;
2350 } else
2351 /* no inode and no name (?!) ... this is odd ... */
2352 continue;
2353
2354 /* match the correct record type */
2355 if (parent) {
2356 if (n->type == AUDIT_TYPE_PARENT ||
2357 n->type == AUDIT_TYPE_UNKNOWN)
2358 goto out;
2359 } else {
2360 if (n->type != AUDIT_TYPE_PARENT)
2361 goto out;
2362 }
2363 }
2364
2365 out_alloc:
2366 /* unable to find an entry with both a matching name and type */
2367 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2368 if (!n)
2369 return;
2370 if (name) {
2371 n->name = name;
2372 atomic_inc(&name->refcnt);
2373 }
2374
2375 out:
2376 if (parent) {
2377 n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
2378 n->type = AUDIT_TYPE_PARENT;
2379 if (flags & AUDIT_INODE_HIDDEN)
2380 n->hidden = true;
2381 } else {
2382 n->name_len = AUDIT_NAME_FULL;
2383 n->type = AUDIT_TYPE_NORMAL;
2384 }
2385 handle_path(dentry);
2386 audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL);
2387 }
2388
__audit_file(const struct file * file)2389 void __audit_file(const struct file *file)
2390 {
2391 __audit_inode(NULL, file->f_path.dentry, 0);
2392 }
2393
2394 /**
2395 * __audit_inode_child - collect inode info for created/removed objects
2396 * @parent: inode of dentry parent
2397 * @dentry: dentry being audited
2398 * @type: AUDIT_TYPE_* value that we're looking for
2399 *
2400 * For syscalls that create or remove filesystem objects, audit_inode
2401 * can only collect information for the filesystem object's parent.
2402 * This call updates the audit context with the child's information.
2403 * Syscalls that create a new filesystem object must be hooked after
2404 * the object is created. Syscalls that remove a filesystem object
2405 * must be hooked prior, in order to capture the target inode during
2406 * unsuccessful attempts.
2407 */
__audit_inode_child(struct inode * parent,const struct dentry * dentry,const unsigned char type)2408 void __audit_inode_child(struct inode *parent,
2409 const struct dentry *dentry,
2410 const unsigned char type)
2411 {
2412 struct audit_context *context = audit_context();
2413 struct inode *inode = d_backing_inode(dentry);
2414 const struct qstr *dname = &dentry->d_name;
2415 struct audit_names *n, *found_parent = NULL, *found_child = NULL;
2416 struct audit_entry *e;
2417 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
2418 int i;
2419
2420 if (context->context == AUDIT_CTX_UNUSED)
2421 return;
2422
2423 rcu_read_lock();
2424 list_for_each_entry_rcu(e, list, list) {
2425 for (i = 0; i < e->rule.field_count; i++) {
2426 struct audit_field *f = &e->rule.fields[i];
2427
2428 if (f->type == AUDIT_FSTYPE
2429 && audit_comparator(parent->i_sb->s_magic,
2430 f->op, f->val)
2431 && e->rule.action == AUDIT_NEVER) {
2432 rcu_read_unlock();
2433 return;
2434 }
2435 }
2436 }
2437 rcu_read_unlock();
2438
2439 if (inode)
2440 handle_one(inode);
2441
2442 /* look for a parent entry first */
2443 list_for_each_entry(n, &context->names_list, list) {
2444 if (!n->name ||
2445 (n->type != AUDIT_TYPE_PARENT &&
2446 n->type != AUDIT_TYPE_UNKNOWN))
2447 continue;
2448
2449 if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev &&
2450 !audit_compare_dname_path(dname,
2451 n->name->name, n->name_len)) {
2452 if (n->type == AUDIT_TYPE_UNKNOWN)
2453 n->type = AUDIT_TYPE_PARENT;
2454 found_parent = n;
2455 break;
2456 }
2457 }
2458
2459 cond_resched();
2460
2461 /* is there a matching child entry? */
2462 list_for_each_entry(n, &context->names_list, list) {
2463 /* can only match entries that have a name */
2464 if (!n->name ||
2465 (n->type != type && n->type != AUDIT_TYPE_UNKNOWN))
2466 continue;
2467
2468 if (!strcmp(dname->name, n->name->name) ||
2469 !audit_compare_dname_path(dname, n->name->name,
2470 found_parent ?
2471 found_parent->name_len :
2472 AUDIT_NAME_FULL)) {
2473 if (n->type == AUDIT_TYPE_UNKNOWN)
2474 n->type = type;
2475 found_child = n;
2476 break;
2477 }
2478 }
2479
2480 if (!found_parent) {
2481 /* create a new, "anonymous" parent record */
2482 n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
2483 if (!n)
2484 return;
2485 audit_copy_inode(n, NULL, parent, 0);
2486 }
2487
2488 if (!found_child) {
2489 found_child = audit_alloc_name(context, type);
2490 if (!found_child)
2491 return;
2492
2493 /* Re-use the name belonging to the slot for a matching parent
2494 * directory. All names for this context are relinquished in
2495 * audit_free_names() */
2496 if (found_parent) {
2497 found_child->name = found_parent->name;
2498 found_child->name_len = AUDIT_NAME_FULL;
2499 atomic_inc(&found_child->name->refcnt);
2500 }
2501 }
2502
2503 if (inode)
2504 audit_copy_inode(found_child, dentry, inode, 0);
2505 else
2506 found_child->ino = AUDIT_INO_UNSET;
2507 }
2508 EXPORT_SYMBOL_GPL(__audit_inode_child);
2509
2510 /**
2511 * auditsc_get_stamp - get local copies of audit_context values
2512 * @ctx: audit_context for the task
2513 * @t: timespec64 to store time recorded in the audit_context
2514 * @serial: serial value that is recorded in the audit_context
2515 *
2516 * Also sets the context as auditable.
2517 */
auditsc_get_stamp(struct audit_context * ctx,struct timespec64 * t,unsigned int * serial)2518 int auditsc_get_stamp(struct audit_context *ctx,
2519 struct timespec64 *t, unsigned int *serial)
2520 {
2521 if (ctx->context == AUDIT_CTX_UNUSED)
2522 return 0;
2523 if (!ctx->serial)
2524 ctx->serial = audit_serial();
2525 t->tv_sec = ctx->ctime.tv_sec;
2526 t->tv_nsec = ctx->ctime.tv_nsec;
2527 *serial = ctx->serial;
2528 if (!ctx->prio) {
2529 ctx->prio = 1;
2530 ctx->current_state = AUDIT_STATE_RECORD;
2531 }
2532 return 1;
2533 }
2534
2535 /**
2536 * __audit_mq_open - record audit data for a POSIX MQ open
2537 * @oflag: open flag
2538 * @mode: mode bits
2539 * @attr: queue attributes
2540 *
2541 */
__audit_mq_open(int oflag,umode_t mode,struct mq_attr * attr)2542 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2543 {
2544 struct audit_context *context = audit_context();
2545
2546 if (attr)
2547 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2548 else
2549 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2550
2551 context->mq_open.oflag = oflag;
2552 context->mq_open.mode = mode;
2553
2554 context->type = AUDIT_MQ_OPEN;
2555 }
2556
2557 /**
2558 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2559 * @mqdes: MQ descriptor
2560 * @msg_len: Message length
2561 * @msg_prio: Message priority
2562 * @abs_timeout: Message timeout in absolute time
2563 *
2564 */
__audit_mq_sendrecv(mqd_t mqdes,size_t msg_len,unsigned int msg_prio,const struct timespec64 * abs_timeout)2565 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2566 const struct timespec64 *abs_timeout)
2567 {
2568 struct audit_context *context = audit_context();
2569 struct timespec64 *p = &context->mq_sendrecv.abs_timeout;
2570
2571 if (abs_timeout)
2572 memcpy(p, abs_timeout, sizeof(*p));
2573 else
2574 memset(p, 0, sizeof(*p));
2575
2576 context->mq_sendrecv.mqdes = mqdes;
2577 context->mq_sendrecv.msg_len = msg_len;
2578 context->mq_sendrecv.msg_prio = msg_prio;
2579
2580 context->type = AUDIT_MQ_SENDRECV;
2581 }
2582
2583 /**
2584 * __audit_mq_notify - record audit data for a POSIX MQ notify
2585 * @mqdes: MQ descriptor
2586 * @notification: Notification event
2587 *
2588 */
2589
__audit_mq_notify(mqd_t mqdes,const struct sigevent * notification)2590 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2591 {
2592 struct audit_context *context = audit_context();
2593
2594 if (notification)
2595 context->mq_notify.sigev_signo = notification->sigev_signo;
2596 else
2597 context->mq_notify.sigev_signo = 0;
2598
2599 context->mq_notify.mqdes = mqdes;
2600 context->type = AUDIT_MQ_NOTIFY;
2601 }
2602
2603 /**
2604 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2605 * @mqdes: MQ descriptor
2606 * @mqstat: MQ flags
2607 *
2608 */
__audit_mq_getsetattr(mqd_t mqdes,struct mq_attr * mqstat)2609 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2610 {
2611 struct audit_context *context = audit_context();
2612
2613 context->mq_getsetattr.mqdes = mqdes;
2614 context->mq_getsetattr.mqstat = *mqstat;
2615 context->type = AUDIT_MQ_GETSETATTR;
2616 }
2617
2618 /**
2619 * __audit_ipc_obj - record audit data for ipc object
2620 * @ipcp: ipc permissions
2621 *
2622 */
__audit_ipc_obj(struct kern_ipc_perm * ipcp)2623 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2624 {
2625 struct audit_context *context = audit_context();
2626
2627 context->ipc.uid = ipcp->uid;
2628 context->ipc.gid = ipcp->gid;
2629 context->ipc.mode = ipcp->mode;
2630 context->ipc.has_perm = 0;
2631 security_ipc_getlsmprop(ipcp, &context->ipc.oprop);
2632 context->type = AUDIT_IPC;
2633 }
2634
2635 /**
2636 * __audit_ipc_set_perm - record audit data for new ipc permissions
2637 * @qbytes: msgq bytes
2638 * @uid: msgq user id
2639 * @gid: msgq group id
2640 * @mode: msgq mode (permissions)
2641 *
2642 * Called only after audit_ipc_obj().
2643 */
__audit_ipc_set_perm(unsigned long qbytes,uid_t uid,gid_t gid,umode_t mode)2644 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
2645 {
2646 struct audit_context *context = audit_context();
2647
2648 context->ipc.qbytes = qbytes;
2649 context->ipc.perm_uid = uid;
2650 context->ipc.perm_gid = gid;
2651 context->ipc.perm_mode = mode;
2652 context->ipc.has_perm = 1;
2653 }
2654
__audit_bprm(struct linux_binprm * bprm)2655 void __audit_bprm(struct linux_binprm *bprm)
2656 {
2657 struct audit_context *context = audit_context();
2658
2659 context->type = AUDIT_EXECVE;
2660 context->execve.argc = bprm->argc;
2661 }
2662
2663
2664 /**
2665 * __audit_socketcall - record audit data for sys_socketcall
2666 * @nargs: number of args, which should not be more than AUDITSC_ARGS.
2667 * @args: args array
2668 *
2669 */
__audit_socketcall(int nargs,unsigned long * args)2670 int __audit_socketcall(int nargs, unsigned long *args)
2671 {
2672 struct audit_context *context = audit_context();
2673
2674 if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
2675 return -EINVAL;
2676 context->type = AUDIT_SOCKETCALL;
2677 context->socketcall.nargs = nargs;
2678 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2679 return 0;
2680 }
2681
2682 /**
2683 * __audit_fd_pair - record audit data for pipe and socketpair
2684 * @fd1: the first file descriptor
2685 * @fd2: the second file descriptor
2686 *
2687 */
__audit_fd_pair(int fd1,int fd2)2688 void __audit_fd_pair(int fd1, int fd2)
2689 {
2690 struct audit_context *context = audit_context();
2691
2692 context->fds[0] = fd1;
2693 context->fds[1] = fd2;
2694 }
2695
2696 /**
2697 * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2698 * @len: data length in user space
2699 * @a: data address in kernel space
2700 *
2701 * Returns 0 for success or NULL context or < 0 on error.
2702 */
__audit_sockaddr(int len,void * a)2703 int __audit_sockaddr(int len, void *a)
2704 {
2705 struct audit_context *context = audit_context();
2706
2707 if (!context->sockaddr) {
2708 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2709
2710 if (!p)
2711 return -ENOMEM;
2712 context->sockaddr = p;
2713 }
2714
2715 context->sockaddr_len = len;
2716 memcpy(context->sockaddr, a, len);
2717 return 0;
2718 }
2719
__audit_ptrace(struct task_struct * t)2720 void __audit_ptrace(struct task_struct *t)
2721 {
2722 struct audit_context *context = audit_context();
2723
2724 context->target_pid = task_tgid_nr(t);
2725 context->target_auid = audit_get_loginuid(t);
2726 context->target_uid = task_uid(t);
2727 context->target_sessionid = audit_get_sessionid(t);
2728 strscpy(context->target_comm, t->comm);
2729 security_task_getlsmprop_obj(t, &context->target_ref);
2730 }
2731
2732 /**
2733 * audit_signal_info_syscall - record signal info for syscalls
2734 * @t: task being signaled
2735 *
2736 * If the audit subsystem is being terminated, record the task (pid)
2737 * and uid that is doing that.
2738 */
audit_signal_info_syscall(struct task_struct * t)2739 int audit_signal_info_syscall(struct task_struct *t)
2740 {
2741 struct audit_aux_data_pids *axp;
2742 struct audit_context *ctx = audit_context();
2743 kuid_t t_uid = task_uid(t);
2744
2745 if (!audit_signals || audit_dummy_context())
2746 return 0;
2747
2748 /* optimize the common case by putting first signal recipient directly
2749 * in audit_context */
2750 if (!ctx->target_pid) {
2751 ctx->target_pid = task_tgid_nr(t);
2752 ctx->target_auid = audit_get_loginuid(t);
2753 ctx->target_uid = t_uid;
2754 ctx->target_sessionid = audit_get_sessionid(t);
2755 strscpy(ctx->target_comm, t->comm);
2756 security_task_getlsmprop_obj(t, &ctx->target_ref);
2757 return 0;
2758 }
2759
2760 axp = (void *)ctx->aux_pids;
2761 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2762 axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2763 if (!axp)
2764 return -ENOMEM;
2765
2766 axp->d.type = AUDIT_OBJ_PID;
2767 axp->d.next = ctx->aux_pids;
2768 ctx->aux_pids = (void *)axp;
2769 }
2770 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2771
2772 axp->target_pid[axp->pid_count] = task_tgid_nr(t);
2773 axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2774 axp->target_uid[axp->pid_count] = t_uid;
2775 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2776 security_task_getlsmprop_obj(t, &axp->target_ref[axp->pid_count]);
2777 strscpy(axp->target_comm[axp->pid_count], t->comm);
2778 axp->pid_count++;
2779
2780 return 0;
2781 }
2782
2783 /**
2784 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2785 * @bprm: pointer to the bprm being processed
2786 * @new: the proposed new credentials
2787 * @old: the old credentials
2788 *
2789 * Simply check if the proc already has the caps given by the file and if not
2790 * store the priv escalation info for later auditing at the end of the syscall
2791 *
2792 * -Eric
2793 */
__audit_log_bprm_fcaps(struct linux_binprm * bprm,const struct cred * new,const struct cred * old)2794 int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2795 const struct cred *new, const struct cred *old)
2796 {
2797 struct audit_aux_data_bprm_fcaps *ax;
2798 struct audit_context *context = audit_context();
2799 struct cpu_vfs_cap_data vcaps;
2800
2801 ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2802 if (!ax)
2803 return -ENOMEM;
2804
2805 ax->d.type = AUDIT_BPRM_FCAPS;
2806 ax->d.next = context->aux;
2807 context->aux = (void *)ax;
2808
2809 get_vfs_caps_from_disk(&nop_mnt_idmap,
2810 bprm->file->f_path.dentry, &vcaps);
2811
2812 ax->fcap.permitted = vcaps.permitted;
2813 ax->fcap.inheritable = vcaps.inheritable;
2814 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2815 ax->fcap.rootid = vcaps.rootid;
2816 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2817
2818 ax->old_pcap.permitted = old->cap_permitted;
2819 ax->old_pcap.inheritable = old->cap_inheritable;
2820 ax->old_pcap.effective = old->cap_effective;
2821 ax->old_pcap.ambient = old->cap_ambient;
2822
2823 ax->new_pcap.permitted = new->cap_permitted;
2824 ax->new_pcap.inheritable = new->cap_inheritable;
2825 ax->new_pcap.effective = new->cap_effective;
2826 ax->new_pcap.ambient = new->cap_ambient;
2827 return 0;
2828 }
2829
2830 /**
2831 * __audit_log_capset - store information about the arguments to the capset syscall
2832 * @new: the new credentials
2833 * @old: the old (current) credentials
2834 *
2835 * Record the arguments userspace sent to sys_capset for later printing by the
2836 * audit system if applicable
2837 */
__audit_log_capset(const struct cred * new,const struct cred * old)2838 void __audit_log_capset(const struct cred *new, const struct cred *old)
2839 {
2840 struct audit_context *context = audit_context();
2841
2842 context->capset.pid = task_tgid_nr(current);
2843 context->capset.cap.effective = new->cap_effective;
2844 context->capset.cap.inheritable = new->cap_effective;
2845 context->capset.cap.permitted = new->cap_permitted;
2846 context->capset.cap.ambient = new->cap_ambient;
2847 context->type = AUDIT_CAPSET;
2848 }
2849
__audit_mmap_fd(int fd,int flags)2850 void __audit_mmap_fd(int fd, int flags)
2851 {
2852 struct audit_context *context = audit_context();
2853
2854 context->mmap.fd = fd;
2855 context->mmap.flags = flags;
2856 context->type = AUDIT_MMAP;
2857 }
2858
__audit_openat2_how(struct open_how * how)2859 void __audit_openat2_how(struct open_how *how)
2860 {
2861 struct audit_context *context = audit_context();
2862
2863 context->openat2.flags = how->flags;
2864 context->openat2.mode = how->mode;
2865 context->openat2.resolve = how->resolve;
2866 context->type = AUDIT_OPENAT2;
2867 }
2868
__audit_log_kern_module(char * name)2869 void __audit_log_kern_module(char *name)
2870 {
2871 struct audit_context *context = audit_context();
2872
2873 context->module.name = kstrdup(name, GFP_KERNEL);
2874 if (!context->module.name)
2875 audit_log_lost("out of memory in __audit_log_kern_module");
2876 context->type = AUDIT_KERN_MODULE;
2877 }
2878
__audit_fanotify(u32 response,struct fanotify_response_info_audit_rule * friar)2879 void __audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar)
2880 {
2881 /* {subj,obj}_trust values are {0,1,2}: no,yes,unknown */
2882 switch (friar->hdr.type) {
2883 case FAN_RESPONSE_INFO_NONE:
2884 audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY,
2885 "resp=%u fan_type=%u fan_info=0 subj_trust=2 obj_trust=2",
2886 response, FAN_RESPONSE_INFO_NONE);
2887 break;
2888 case FAN_RESPONSE_INFO_AUDIT_RULE:
2889 audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY,
2890 "resp=%u fan_type=%u fan_info=%X subj_trust=%u obj_trust=%u",
2891 response, friar->hdr.type, friar->rule_number,
2892 friar->subj_trust, friar->obj_trust);
2893 }
2894 }
2895
__audit_tk_injoffset(struct timespec64 offset)2896 void __audit_tk_injoffset(struct timespec64 offset)
2897 {
2898 struct audit_context *context = audit_context();
2899
2900 /* only set type if not already set by NTP */
2901 if (!context->type)
2902 context->type = AUDIT_TIME_INJOFFSET;
2903 memcpy(&context->time.tk_injoffset, &offset, sizeof(offset));
2904 }
2905
__audit_ntp_log(const struct audit_ntp_data * ad)2906 void __audit_ntp_log(const struct audit_ntp_data *ad)
2907 {
2908 struct audit_context *context = audit_context();
2909 int type;
2910
2911 for (type = 0; type < AUDIT_NTP_NVALS; type++)
2912 if (ad->vals[type].newval != ad->vals[type].oldval) {
2913 /* unconditionally set type, overwriting TK */
2914 context->type = AUDIT_TIME_ADJNTPVAL;
2915 memcpy(&context->time.ntp_data, ad, sizeof(*ad));
2916 break;
2917 }
2918 }
2919
__audit_log_nfcfg(const char * name,u8 af,unsigned int nentries,enum audit_nfcfgop op,gfp_t gfp)2920 void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
2921 enum audit_nfcfgop op, gfp_t gfp)
2922 {
2923 struct audit_buffer *ab;
2924 char comm[sizeof(current->comm)];
2925
2926 ab = audit_log_start(audit_context(), gfp, AUDIT_NETFILTER_CFG);
2927 if (!ab)
2928 return;
2929 audit_log_format(ab, "table=%s family=%u entries=%u op=%s",
2930 name, af, nentries, audit_nfcfgs[op].s);
2931
2932 audit_log_format(ab, " pid=%u", task_tgid_nr(current));
2933 audit_log_task_context(ab); /* subj= */
2934 audit_log_format(ab, " comm=");
2935 audit_log_untrustedstring(ab, get_task_comm(comm, current));
2936 audit_log_end(ab);
2937 }
2938 EXPORT_SYMBOL_GPL(__audit_log_nfcfg);
2939
audit_log_task(struct audit_buffer * ab)2940 static void audit_log_task(struct audit_buffer *ab)
2941 {
2942 kuid_t auid, uid;
2943 kgid_t gid;
2944 unsigned int sessionid;
2945 char comm[sizeof(current->comm)];
2946
2947 auid = audit_get_loginuid(current);
2948 sessionid = audit_get_sessionid(current);
2949 current_uid_gid(&uid, &gid);
2950
2951 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2952 from_kuid(&init_user_ns, auid),
2953 from_kuid(&init_user_ns, uid),
2954 from_kgid(&init_user_ns, gid),
2955 sessionid);
2956 audit_log_task_context(ab);
2957 audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current));
2958 audit_log_untrustedstring(ab, get_task_comm(comm, current));
2959 audit_log_d_path_exe(ab, current->mm);
2960 }
2961
2962 /**
2963 * audit_core_dumps - record information about processes that end abnormally
2964 * @signr: signal value
2965 *
2966 * If a process ends with a core dump, something fishy is going on and we
2967 * should record the event for investigation.
2968 */
audit_core_dumps(long signr)2969 void audit_core_dumps(long signr)
2970 {
2971 struct audit_buffer *ab;
2972
2973 if (!audit_enabled)
2974 return;
2975
2976 if (signr == SIGQUIT) /* don't care for those */
2977 return;
2978
2979 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND);
2980 if (unlikely(!ab))
2981 return;
2982 audit_log_task(ab);
2983 audit_log_format(ab, " sig=%ld res=1", signr);
2984 audit_log_end(ab);
2985 }
2986
2987 /**
2988 * audit_seccomp - record information about a seccomp action
2989 * @syscall: syscall number
2990 * @signr: signal value
2991 * @code: the seccomp action
2992 *
2993 * Record the information associated with a seccomp action. Event filtering for
2994 * seccomp actions that are not to be logged is done in seccomp_log().
2995 * Therefore, this function forces auditing independent of the audit_enabled
2996 * and dummy context state because seccomp actions should be logged even when
2997 * audit is not in use.
2998 */
audit_seccomp(unsigned long syscall,long signr,int code)2999 void audit_seccomp(unsigned long syscall, long signr, int code)
3000 {
3001 struct audit_buffer *ab;
3002
3003 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP);
3004 if (unlikely(!ab))
3005 return;
3006 audit_log_task(ab);
3007 audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
3008 signr, syscall_get_arch(current), syscall,
3009 in_compat_syscall(), KSTK_EIP(current), code);
3010 audit_log_end(ab);
3011 }
3012
audit_seccomp_actions_logged(const char * names,const char * old_names,int res)3013 void audit_seccomp_actions_logged(const char *names, const char *old_names,
3014 int res)
3015 {
3016 struct audit_buffer *ab;
3017
3018 if (!audit_enabled)
3019 return;
3020
3021 ab = audit_log_start(audit_context(), GFP_KERNEL,
3022 AUDIT_CONFIG_CHANGE);
3023 if (unlikely(!ab))
3024 return;
3025
3026 audit_log_format(ab,
3027 "op=seccomp-logging actions=%s old-actions=%s res=%d",
3028 names, old_names, res);
3029 audit_log_end(ab);
3030 }
3031
audit_killed_trees(void)3032 struct list_head *audit_killed_trees(void)
3033 {
3034 struct audit_context *ctx = audit_context();
3035 if (likely(!ctx || ctx->context == AUDIT_CTX_UNUSED))
3036 return NULL;
3037 return &ctx->killed_trees;
3038 }
3039