blob: 9bc0b0301198c170ef794a02c95cfb5c5f576f73 [file] [log] [blame]
Thomas Gleixner1a59d1b82019-05-27 08:55:05 +02001// SPDX-License-Identifier: GPL-2.0-or-later
85c87212005-04-29 16:23:29 +01002/* audit.c -- Auditing support
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 * Gateway between the kernel (e.g., selinux) and the user-space audit daemon.
4 * System-call specific features have moved to auditsc.c
5 *
Steve Grubb6a01b07f2007-01-19 14:39:55 -05006 * Copyright 2003-2007 Red Hat Inc., Durham, North Carolina.
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * All Rights Reserved.
8 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
10 *
Ahmed S. Darwishd7a96f32008-03-01 22:01:11 +020011 * Goals: 1) Integrate fully with Security Modules.
Linus Torvalds1da177e2005-04-16 15:20:36 -070012 * 2) Minimal run-time overhead:
13 * a) Minimal when syscall auditing is disabled (audit_enable=0).
14 * b) Small when syscall auditing is enabled and no audit record
15 * is generated (defer as much work as possible to record
16 * generation time):
17 * i) context is allocated,
18 * ii) names from getname are stored without a copy, and
19 * iii) inode information stored from path_lookup.
20 * 3) Ability to disable syscall auditing at boot time (audit=0).
21 * 4) Usable by other parts of the kernel (if audit_log* is called,
22 * then a syscall record will be generated automatically for the
23 * current syscall).
24 * 5) Netlink interface to user-space.
25 * 6) Support low-overhead kernel-based filtering to minimize the
26 * information that must be passed to user-space.
27 *
Richard Guy Briggsd590dca2018-02-03 00:33:11 -050028 * Audit userspace, documentation, tests, and bug/issue trackers:
29 * https://github.com/linux-audit
Linus Torvalds1da177e2005-04-16 15:20:36 -070030 */
31
Joe Perchesd957f7b2014-01-14 10:33:12 -080032#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
33
Davidlohr Bueso5b282552015-02-22 18:20:09 -080034#include <linux/file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035#include <linux/init.h>
Paul McQuade7153e402014-06-06 14:37:37 -070036#include <linux/types.h>
Arun Sharma600634972011-07-26 16:09:06 -070037#include <linux/atomic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#include <linux/mm.h>
Paul Gortmaker9984de12011-05-23 14:51:41 -040039#include <linux/export.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090040#include <linux/slab.h>
David Woodhouseb7d11252005-05-19 10:56:58 +010041#include <linux/err.h>
42#include <linux/kthread.h>
Richard Guy Briggs46e959e2013-05-03 14:03:50 -040043#include <linux/kernel.h>
Eric Parisb24a30a2013-04-30 15:30:32 -040044#include <linux/syscalls.h>
Paul Moore5b523302017-03-21 11:26:35 -040045#include <linux/spinlock.h>
46#include <linux/rcupdate.h>
47#include <linux/mutex.h>
48#include <linux/gfp.h>
Paul Mooreb6c7c112017-05-02 10:16:05 -040049#include <linux/pid.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
51#include <linux/audit.h>
52
53#include <net/sock.h>
Amy Griffis93315ed2006-02-07 12:05:27 -050054#include <net/netlink.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070055#include <linux/skbuff.h>
Mr Dash Four131ad622011-06-30 13:31:57 +020056#ifdef CONFIG_SECURITY
57#include <linux/security.h>
58#endif
Nigel Cunningham7dfb7102006-12-06 20:34:23 -080059#include <linux/freezer.h>
Eric W. Biederman34e36d8e2012-09-10 23:20:20 -070060#include <linux/pid_namespace.h>
Richard Guy Briggs33faba72013-07-16 13:18:45 -040061#include <net/netns/generic.h>
Darrel Goeddel3dc7e312006-03-10 18:14:06 -060062
63#include "audit.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Eric Parisa3f07112008-11-05 12:47:09 -050065/* No auditing will take place until audit_initialized == AUDIT_INITIALIZED.
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 * (Initialization happens after skb_init is called.) */
Eric Parisa3f07112008-11-05 12:47:09 -050067#define AUDIT_DISABLED -1
68#define AUDIT_UNINITIALIZED 0
69#define AUDIT_INITIALIZED 1
Alex Shiba59eae72020-11-06 16:31:22 +080070static int audit_initialized = AUDIT_UNINITIALIZED;
Linus Torvalds1da177e2005-04-16 15:20:36 -070071
Paul Moore173743d2017-09-01 09:44:34 -040072u32 audit_enabled = AUDIT_OFF;
Paul Mooreb3b4fdf2017-09-01 09:44:57 -040073bool audit_ever_enabled = !!AUDIT_OFF;
Linus Torvalds1da177e2005-04-16 15:20:36 -070074
Jan Engelhardtae9d67af2011-01-18 06:48:12 +010075EXPORT_SYMBOL_GPL(audit_enabled);
76
Linus Torvalds1da177e2005-04-16 15:20:36 -070077/* Default state when kernel boots without any parameters. */
Paul Moore173743d2017-09-01 09:44:34 -040078static u32 audit_default = AUDIT_OFF;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
80/* If auditing cannot proceed, audit_failure selects what happens. */
Joe Perches3e1d0bb2014-01-14 10:33:13 -080081static u32 audit_failure = AUDIT_FAIL_PRINTK;
Linus Torvalds1da177e2005-04-16 15:20:36 -070082
Paul Moore5b523302017-03-21 11:26:35 -040083/* private audit network namespace index */
84static unsigned int audit_net_id;
85
86/**
87 * struct audit_net - audit private network namespace data
88 * @sk: communication socket
Pavel Emelyanov75c03712008-03-20 15:39:41 -070089 */
Paul Moore5b523302017-03-21 11:26:35 -040090struct audit_net {
91 struct sock *sk;
92};
93
94/**
95 * struct auditd_connection - kernel/auditd connection state
96 * @pid: auditd PID
97 * @portid: netlink portid
98 * @net: the associated network namespace
Paul Moore48d0e022017-05-02 10:16:05 -040099 * @rcu: RCU head
Paul Moore5b523302017-03-21 11:26:35 -0400100 *
101 * Description:
102 * This struct is RCU protected; you must either hold the RCU lock for reading
Paul Moore48d0e022017-05-02 10:16:05 -0400103 * or the associated spinlock for writing.
Paul Moore5b523302017-03-21 11:26:35 -0400104 */
Amol Grovercb5172d2019-12-02 00:03:48 +0530105struct auditd_connection {
Paul Mooreb6c7c112017-05-02 10:16:05 -0400106 struct pid *pid;
Paul Moore5b523302017-03-21 11:26:35 -0400107 u32 portid;
108 struct net *net;
Paul Moore48d0e022017-05-02 10:16:05 -0400109 struct rcu_head rcu;
Amol Grovercb5172d2019-12-02 00:03:48 +0530110};
111static struct auditd_connection __rcu *auditd_conn;
Paul Moore48d0e022017-05-02 10:16:05 -0400112static DEFINE_SPINLOCK(auditd_conn_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700114/* If audit_rate_limit is non-zero, limit the rate of sending audit records
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 * to that number per second. This prevents DoS attacks, but results in
116 * audit records being dropped. */
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800117static u32 audit_rate_limit;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118
Richard Guy Briggs40c07752013-10-22 13:28:49 -0400119/* Number of outstanding audit_buffers allowed.
120 * When set to zero, this means unlimited. */
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800121static u32 audit_backlog_limit = 64;
Richard Guy Briggse789e562013-09-12 23:03:51 -0400122#define AUDIT_BACKLOG_WAIT_TIME (60 * HZ)
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800123static u32 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124
Steve Grubbc2f0c7c2005-05-06 12:38:39 +0100125/* The identity of the user shutting down the audit system. */
Jules Irenge6b870242020-08-03 13:34:38 +0100126static kuid_t audit_sig_uid = INVALID_UID;
127static pid_t audit_sig_pid = -1;
Jules Irenge265c3202020-08-03 13:34:39 +0100128static u32 audit_sig_sid;
Steve Grubbc2f0c7c2005-05-06 12:38:39 +0100129
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130/* Records can be lost in several ways:
131 0) [suppressed in audit_alloc]
132 1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
133 2) out of memory in audit_log_move [alloc_skb]
134 3) suppressed due to audit_rate_limit
135 4) suppressed due to audit_backlog_limit
136*/
Richard Guy Briggs92c82e82017-01-13 03:26:29 -0500137static atomic_t audit_lost = ATOMIC_INIT(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138
Max Englanderb43870c2020-07-04 15:15:28 +0000139/* Monotonically increasing sum of time the kernel has spent
140 * waiting while the backlog limit is exceeded.
141 */
142static atomic_t audit_backlog_wait_time_actual = ATOMIC_INIT(0);
143
Amy Griffisf368c07d2006-04-07 16:55:56 -0400144/* Hash for inode-based rules */
145struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
146
Paul Moore8cc96382017-05-02 10:16:05 -0400147static struct kmem_cache *audit_buffer_cache;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148
Paul Moorec6480202016-11-29 16:53:25 -0500149/* queue msgs to send via kauditd_task */
Paul Mooreaf8b8242016-11-29 16:53:24 -0500150static struct sk_buff_head audit_queue;
Paul Moorec6480202016-11-29 16:53:25 -0500151/* queue msgs due to temporary unicast send problems */
152static struct sk_buff_head audit_retry_queue;
153/* queue msgs waiting for new auditd connection */
Paul Mooreaf8b8242016-11-29 16:53:24 -0500154static struct sk_buff_head audit_hold_queue;
Paul Moorec6480202016-11-29 16:53:25 -0500155
156/* queue servicing thread */
David Woodhouseb7d11252005-05-19 10:56:58 +0100157static struct task_struct *kauditd_task;
158static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
Paul Moorec6480202016-11-29 16:53:25 -0500159
160/* waitqueue for callers who are blocked on the audit backlog */
David Woodhouse9ad9ad32005-06-22 15:04:33 +0100161static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
Eric Parisb0fed402013-05-22 12:54:49 -0400163static struct audit_features af = {.vers = AUDIT_FEATURE_VERSION,
164 .mask = -1,
165 .features = 0,
166 .lock = 0,};
167
Eric Paris21b85c32013-05-23 14:26:00 -0400168static char *audit_feature_names[2] = {
Eric Parisd040e5a2013-05-24 09:18:04 -0400169 "only_unset_loginuid",
Eric Paris21b85c32013-05-23 14:26:00 -0400170 "loginuid_immutable",
Eric Parisb0fed402013-05-22 12:54:49 -0400171};
172
Paul Moorece4236312018-02-20 09:52:38 -0500173/**
174 * struct audit_ctl_mutex - serialize requests from userspace
175 * @lock: the mutex used for locking
176 * @owner: the task which owns the lock
177 *
178 * Description:
179 * This is the lock struct used to ensure we only process userspace requests
180 * in an orderly fashion. We can't simply use a mutex/lock here because we
181 * need to track lock ownership so we don't end up blocking the lock owner in
182 * audit_log_start() or similar.
183 */
184static struct audit_ctl_mutex {
185 struct mutex lock;
186 void *owner;
187} audit_cmd_mutex;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188
189/* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
190 * audit records. Since printk uses a 1024 byte buffer, this buffer
191 * should be at least that large. */
192#define AUDIT_BUFSIZ 1024
193
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194/* The audit_buffer is used when formatting an audit record. The caller
195 * locks briefly to get the record off the freelist or to allocate the
196 * buffer, and locks briefly to send the buffer to the netlink layer or
197 * to place it on a transmit queue. Multiple audit_buffers can be in
198 * use simultaneously. */
199struct audit_buffer {
Chris Wright8fc61152005-05-06 15:54:17 +0100200 struct sk_buff *skb; /* formatted skb ready to send */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 struct audit_context *ctx; /* NULL or associated context */
Al Viro9796fdd2005-10-21 03:22:03 -0400202 gfp_t gfp_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203};
204
Eric Parisf09ac9d2008-04-18 10:11:04 -0400205struct audit_reply {
Richard Guy Briggsf9441632013-08-14 11:32:45 -0400206 __u32 portid;
Eric W. Biederman638a0fd2014-02-28 10:49:05 -0800207 struct net *net;
Eric Parisf09ac9d2008-04-18 10:11:04 -0400208 struct sk_buff *skb;
209};
210
Paul Moore5b523302017-03-21 11:26:35 -0400211/**
212 * auditd_test_task - Check to see if a given task is an audit daemon
213 * @task: the task to check
214 *
215 * Description:
216 * Return 1 if the task is a registered audit daemon, 0 otherwise.
217 */
Paul Mooreb6c7c112017-05-02 10:16:05 -0400218int auditd_test_task(struct task_struct *task)
Paul Moore5b523302017-03-21 11:26:35 -0400219{
220 int rc;
Paul Moore48d0e022017-05-02 10:16:05 -0400221 struct auditd_connection *ac;
Paul Moore5b523302017-03-21 11:26:35 -0400222
223 rcu_read_lock();
Paul Moore48d0e022017-05-02 10:16:05 -0400224 ac = rcu_dereference(auditd_conn);
225 rc = (ac && ac->pid == task_tgid(task) ? 1 : 0);
Paul Moore5b523302017-03-21 11:26:35 -0400226 rcu_read_unlock();
227
228 return rc;
229}
230
231/**
Paul Moorece4236312018-02-20 09:52:38 -0500232 * audit_ctl_lock - Take the audit control lock
233 */
234void audit_ctl_lock(void)
235{
236 mutex_lock(&audit_cmd_mutex.lock);
237 audit_cmd_mutex.owner = current;
238}
239
240/**
241 * audit_ctl_unlock - Drop the audit control lock
242 */
243void audit_ctl_unlock(void)
244{
245 audit_cmd_mutex.owner = NULL;
246 mutex_unlock(&audit_cmd_mutex.lock);
247}
248
249/**
250 * audit_ctl_owner_current - Test to see if the current task owns the lock
251 *
252 * Description:
253 * Return true if the current task owns the audit control lock, false if it
254 * doesn't own the lock.
255 */
256static bool audit_ctl_owner_current(void)
257{
258 return (current == audit_cmd_mutex.owner);
259}
260
261/**
Paul Mooreb6c7c112017-05-02 10:16:05 -0400262 * auditd_pid_vnr - Return the auditd PID relative to the namespace
Paul Mooreb6c7c112017-05-02 10:16:05 -0400263 *
264 * Description:
Paul Moore48d0e022017-05-02 10:16:05 -0400265 * Returns the PID in relation to the namespace, 0 on failure.
Paul Mooreb6c7c112017-05-02 10:16:05 -0400266 */
Paul Moore48d0e022017-05-02 10:16:05 -0400267static pid_t auditd_pid_vnr(void)
Paul Mooreb6c7c112017-05-02 10:16:05 -0400268{
269 pid_t pid;
Paul Moore48d0e022017-05-02 10:16:05 -0400270 const struct auditd_connection *ac;
Paul Mooreb6c7c112017-05-02 10:16:05 -0400271
272 rcu_read_lock();
Paul Moore48d0e022017-05-02 10:16:05 -0400273 ac = rcu_dereference(auditd_conn);
274 if (!ac || !ac->pid)
Paul Mooreb6c7c112017-05-02 10:16:05 -0400275 pid = 0;
276 else
Paul Moore48d0e022017-05-02 10:16:05 -0400277 pid = pid_vnr(ac->pid);
Paul Mooreb6c7c112017-05-02 10:16:05 -0400278 rcu_read_unlock();
279
280 return pid;
281}
282
283/**
Paul Moore5b523302017-03-21 11:26:35 -0400284 * audit_get_sk - Return the audit socket for the given network namespace
285 * @net: the destination network namespace
286 *
287 * Description:
288 * Returns the sock pointer if valid, NULL otherwise. The caller must ensure
289 * that a reference is held for the network namespace while the sock is in use.
290 */
291static struct sock *audit_get_sk(const struct net *net)
292{
293 struct audit_net *aunet;
294
295 if (!net)
296 return NULL;
297
298 aunet = net_generic(net, audit_net_id);
299 return aunet->sk;
300}
301
Dustin Kirkland8c8570f2005-11-03 17:15:16 +0000302void audit_panic(const char *message)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303{
Joe Perchesd957f7b2014-01-14 10:33:12 -0800304 switch (audit_failure) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 case AUDIT_FAIL_SILENT:
306 break;
307 case AUDIT_FAIL_PRINTK:
Eric Paris320f1b12008-01-23 22:55:05 -0500308 if (printk_ratelimit())
Joe Perchesd957f7b2014-01-14 10:33:12 -0800309 pr_err("%s\n", message);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 break;
311 case AUDIT_FAIL_PANIC:
Paul Moore5b523302017-03-21 11:26:35 -0400312 panic("audit: %s\n", message);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 break;
314 }
315}
316
317static inline int audit_rate_check(void)
318{
319 static unsigned long last_check = 0;
320 static int messages = 0;
321 static DEFINE_SPINLOCK(lock);
322 unsigned long flags;
323 unsigned long now;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 int retval = 0;
325
326 if (!audit_rate_limit) return 1;
327
328 spin_lock_irqsave(&lock, flags);
329 if (++messages < audit_rate_limit) {
330 retval = 1;
331 } else {
wuchi501e4bb2022-08-30 00:26:09 +0800332 now = jiffies;
333 if (time_after(now, last_check + HZ)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 last_check = now;
335 messages = 0;
336 retval = 1;
337 }
338 }
339 spin_unlock_irqrestore(&lock, flags);
340
341 return retval;
342}
343
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700344/**
345 * audit_log_lost - conditionally log lost audit message event
346 * @message: the message stating reason for lost audit message
347 *
348 * Emit at least 1 message per second, even if audit_rate_check is
349 * throttling.
350 * Always increment the lost messages counter.
351*/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352void audit_log_lost(const char *message)
353{
354 static unsigned long last_msg = 0;
355 static DEFINE_SPINLOCK(lock);
356 unsigned long flags;
357 unsigned long now;
358 int print;
359
360 atomic_inc(&audit_lost);
361
362 print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit);
363
364 if (!print) {
365 spin_lock_irqsave(&lock, flags);
366 now = jiffies;
wuchi501e4bb2022-08-30 00:26:09 +0800367 if (time_after(now, last_msg + HZ)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 print = 1;
369 last_msg = now;
370 }
371 spin_unlock_irqrestore(&lock, flags);
372 }
373
374 if (print) {
Eric Paris320f1b12008-01-23 22:55:05 -0500375 if (printk_ratelimit())
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800376 pr_warn("audit_lost=%u audit_rate_limit=%u audit_backlog_limit=%u\n",
Eric Paris320f1b12008-01-23 22:55:05 -0500377 atomic_read(&audit_lost),
378 audit_rate_limit,
379 audit_backlog_limit);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 audit_panic(message);
381 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382}
383
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800384static int audit_log_config_change(char *function_name, u32 new, u32 old,
Eric Paris25323862008-04-18 10:09:25 -0400385 int allow_changes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386{
Eric Paris1a6b9f22008-01-07 17:09:31 -0500387 struct audit_buffer *ab;
388 int rc = 0;
Steve Grubb6a01b07f2007-01-19 14:39:55 -0500389
Richard Guy Briggs626abcd2019-01-18 17:42:48 -0500390 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_CONFIG_CHANGE);
Kees Cook0644ec02013-01-11 14:32:07 -0800391 if (unlikely(!ab))
392 return rc;
Richard Guy Briggs53fc7a02018-12-10 17:17:48 -0500393 audit_log_format(ab, "op=set %s=%u old=%u ", function_name, new, old);
Eric Paris4d3fb702013-04-30 09:53:34 -0400394 audit_log_session_info(ab);
Eric Parisb122c372013-04-19 15:00:33 -0400395 rc = audit_log_task_context(ab);
396 if (rc)
397 allow_changes = 0; /* Something weird, deny request */
Eric Paris1a6b9f22008-01-07 17:09:31 -0500398 audit_log_format(ab, " res=%d", allow_changes);
399 audit_log_end(ab);
400 return rc;
401}
402
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800403static int audit_do_config_change(char *function_name, u32 *to_change, u32 new)
Eric Paris1a6b9f22008-01-07 17:09:31 -0500404{
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800405 int allow_changes, rc = 0;
406 u32 old = *to_change;
Eric Paris1a6b9f22008-01-07 17:09:31 -0500407
408 /* check if we are locked */
409 if (audit_enabled == AUDIT_LOCKED)
410 allow_changes = 0;
411 else
412 allow_changes = 1;
413
414 if (audit_enabled != AUDIT_OFF) {
Eric Parisdc9eb692013-04-19 13:23:09 -0400415 rc = audit_log_config_change(function_name, new, old, allow_changes);
Eric Paris1a6b9f22008-01-07 17:09:31 -0500416 if (rc)
417 allow_changes = 0;
418 }
Steve Grubb6a01b07f2007-01-19 14:39:55 -0500419
420 /* If we are allowed, make the change */
Eric Paris1a6b9f22008-01-07 17:09:31 -0500421 if (allow_changes == 1)
422 *to_change = new;
Steve Grubb6a01b07f2007-01-19 14:39:55 -0500423 /* Not allowed, update reason */
424 else if (rc == 0)
425 rc = -EPERM;
426 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427}
428
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800429static int audit_set_rate_limit(u32 limit)
Eric Paris1a6b9f22008-01-07 17:09:31 -0500430{
Eric Parisdc9eb692013-04-19 13:23:09 -0400431 return audit_do_config_change("audit_rate_limit", &audit_rate_limit, limit);
Eric Paris1a6b9f22008-01-07 17:09:31 -0500432}
433
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800434static int audit_set_backlog_limit(u32 limit)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435{
Eric Parisdc9eb692013-04-19 13:23:09 -0400436 return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, limit);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437}
438
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800439static int audit_set_backlog_wait_time(u32 timeout)
Richard Guy Briggs51cc83f2013-09-18 11:55:12 -0400440{
441 return audit_do_config_change("audit_backlog_wait_time",
Paul Moore31975422016-11-29 16:53:25 -0500442 &audit_backlog_wait_time, timeout);
Richard Guy Briggs51cc83f2013-09-18 11:55:12 -0400443}
444
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800445static int audit_set_enabled(u32 state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446{
Eric Parisb593d382008-01-08 17:38:31 -0500447 int rc;
Pranith Kumar724e7bf2015-03-11 14:08:19 -0400448 if (state > AUDIT_LOCKED)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 return -EINVAL;
Steve Grubbce29b682006-04-01 18:29:34 -0500450
Eric Parisdc9eb692013-04-19 13:23:09 -0400451 rc = audit_do_config_change("audit_enabled", &audit_enabled, state);
Eric Parisb593d382008-01-08 17:38:31 -0500452 if (!rc)
453 audit_ever_enabled |= !!state;
454
455 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456}
457
Joe Perches3e1d0bb2014-01-14 10:33:13 -0800458static int audit_set_failure(u32 state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 if (state != AUDIT_FAIL_SILENT
461 && state != AUDIT_FAIL_PRINTK
462 && state != AUDIT_FAIL_PANIC)
463 return -EINVAL;
Steve Grubbce29b682006-04-01 18:29:34 -0500464
Eric Parisdc9eb692013-04-19 13:23:09 -0400465 return audit_do_config_change("audit_failure", &audit_failure, state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466}
467
Paul Moore5b523302017-03-21 11:26:35 -0400468/**
Paul Moore48d0e022017-05-02 10:16:05 -0400469 * auditd_conn_free - RCU helper to release an auditd connection struct
470 * @rcu: RCU head
471 *
472 * Description:
473 * Drop any references inside the auditd connection tracking struct and free
474 * the memory.
475 */
Joe Perches447a5642018-03-21 15:09:32 -0700476static void auditd_conn_free(struct rcu_head *rcu)
477{
Paul Moore48d0e022017-05-02 10:16:05 -0400478 struct auditd_connection *ac;
479
480 ac = container_of(rcu, struct auditd_connection, rcu);
481 put_pid(ac->pid);
482 put_net(ac->net);
483 kfree(ac);
Joe Perches447a5642018-03-21 15:09:32 -0700484}
Paul Moore48d0e022017-05-02 10:16:05 -0400485
486/**
Paul Moore5b523302017-03-21 11:26:35 -0400487 * auditd_set - Set/Reset the auditd connection state
488 * @pid: auditd PID
489 * @portid: auditd netlink portid
490 * @net: auditd network namespace pointer
491 *
492 * Description:
493 * This function will obtain and drop network namespace references as
Paul Moore48d0e022017-05-02 10:16:05 -0400494 * necessary. Returns zero on success, negative values on failure.
Paul Moore5b523302017-03-21 11:26:35 -0400495 */
Paul Moore48d0e022017-05-02 10:16:05 -0400496static int auditd_set(struct pid *pid, u32 portid, struct net *net)
Paul Moore5b523302017-03-21 11:26:35 -0400497{
498 unsigned long flags;
Paul Moore48d0e022017-05-02 10:16:05 -0400499 struct auditd_connection *ac_old, *ac_new;
Paul Moore5b523302017-03-21 11:26:35 -0400500
Paul Moore48d0e022017-05-02 10:16:05 -0400501 if (!pid || !net)
502 return -EINVAL;
503
504 ac_new = kzalloc(sizeof(*ac_new), GFP_KERNEL);
505 if (!ac_new)
506 return -ENOMEM;
507 ac_new->pid = get_pid(pid);
508 ac_new->portid = portid;
509 ac_new->net = get_net(net);
510
511 spin_lock_irqsave(&auditd_conn_lock, flags);
512 ac_old = rcu_dereference_protected(auditd_conn,
513 lockdep_is_held(&auditd_conn_lock));
514 rcu_assign_pointer(auditd_conn, ac_new);
515 spin_unlock_irqrestore(&auditd_conn_lock, flags);
516
517 if (ac_old)
518 call_rcu(&ac_old->rcu, auditd_conn_free);
519
520 return 0;
Paul Moore5b523302017-03-21 11:26:35 -0400521}
522
523/**
Mauro Carvalho Chehabcbb52622020-10-23 18:33:38 +0200524 * kauditd_printk_skb - Print the audit record to the ring buffer
Paul Moore5b523302017-03-21 11:26:35 -0400525 * @skb: audit record
526 *
527 * Whatever the reason, this packet may not make it to the auditd connection
528 * so write it via printk so the information isn't completely lost.
Eric Paris038cbcf2009-06-11 14:31:35 -0400529 */
Paul Mooreaf8b8242016-11-29 16:53:24 -0500530static void kauditd_printk_skb(struct sk_buff *skb)
Eric Paris038cbcf2009-06-11 14:31:35 -0400531{
532 struct nlmsghdr *nlh = nlmsg_hdr(skb);
David S. Millerc64e66c2012-06-26 21:45:21 -0700533 char *data = nlmsg_data(nlh);
Eric Paris038cbcf2009-06-11 14:31:35 -0400534
Paul Moore5b523302017-03-21 11:26:35 -0400535 if (nlh->nlmsg_type != AUDIT_EOE && printk_ratelimit())
536 pr_notice("type=%d %s\n", nlh->nlmsg_type, data);
537}
538
539/**
540 * kauditd_rehold_skb - Handle a audit record send failure in the hold queue
541 * @skb: audit record
Paul Mooref26d0432022-01-13 18:54:38 -0500542 * @error: error code (unused)
Paul Moore5b523302017-03-21 11:26:35 -0400543 *
544 * Description:
545 * This should only be used by the kauditd_thread when it fails to flush the
546 * hold queue.
547 */
Paul Mooref26d0432022-01-13 18:54:38 -0500548static void kauditd_rehold_skb(struct sk_buff *skb, __always_unused int error)
Paul Moore5b523302017-03-21 11:26:35 -0400549{
Paul Mooref26d0432022-01-13 18:54:38 -0500550 /* put the record back in the queue */
551 skb_queue_tail(&audit_hold_queue, skb);
Eric Paris038cbcf2009-06-11 14:31:35 -0400552}
553
Paul Moorec6480202016-11-29 16:53:25 -0500554/**
555 * kauditd_hold_skb - Queue an audit record, waiting for auditd
556 * @skb: audit record
Paul Mooref26d0432022-01-13 18:54:38 -0500557 * @error: error code
Paul Moorec6480202016-11-29 16:53:25 -0500558 *
559 * Description:
560 * Queue the audit record, waiting for an instance of auditd. When this
561 * function is called we haven't given up yet on sending the record, but things
562 * are not looking good. The first thing we want to do is try to write the
563 * record via printk and then see if we want to try and hold on to the record
564 * and queue it, if we have room. If we want to hold on to the record, but we
565 * don't have room, record a record lost message.
566 */
Paul Mooref26d0432022-01-13 18:54:38 -0500567static void kauditd_hold_skb(struct sk_buff *skb, int error)
Eric Parisf3d357b2008-04-18 10:02:28 -0400568{
Paul Moorec6480202016-11-29 16:53:25 -0500569 /* at this point it is uncertain if we will ever send this to auditd so
570 * try to send the message via printk before we go any further */
571 kauditd_printk_skb(skb);
Richard Guy Briggs32a1dba2015-11-04 08:23:50 -0500572
Paul Moorec6480202016-11-29 16:53:25 -0500573 /* can we just silently drop the message? */
Paul Mooref26d0432022-01-13 18:54:38 -0500574 if (!audit_default)
575 goto drop;
576
577 /* the hold queue is only for when the daemon goes away completely,
578 * not -EAGAIN failures; if we are in a -EAGAIN state requeue the
579 * record on the retry queue unless it's full, in which case drop it
580 */
581 if (error == -EAGAIN) {
582 if (!audit_backlog_limit ||
583 skb_queue_len(&audit_retry_queue) < audit_backlog_limit) {
584 skb_queue_tail(&audit_retry_queue, skb);
585 return;
586 }
587 audit_log_lost("kauditd retry queue overflow");
588 goto drop;
Paul Moorec6480202016-11-29 16:53:25 -0500589 }
590
Paul Mooref26d0432022-01-13 18:54:38 -0500591 /* if we have room in the hold queue, queue the message */
Paul Moorec6480202016-11-29 16:53:25 -0500592 if (!audit_backlog_limit ||
593 skb_queue_len(&audit_hold_queue) < audit_backlog_limit) {
594 skb_queue_tail(&audit_hold_queue, skb);
595 return;
596 }
597
598 /* we have no other options - drop the message */
599 audit_log_lost("kauditd hold queue overflow");
Paul Mooref26d0432022-01-13 18:54:38 -0500600drop:
Paul Moorec6480202016-11-29 16:53:25 -0500601 kfree_skb(skb);
602}
603
604/**
605 * kauditd_retry_skb - Queue an audit record, attempt to send again to auditd
606 * @skb: audit record
Paul Mooref26d0432022-01-13 18:54:38 -0500607 * @error: error code (unused)
Paul Moorec6480202016-11-29 16:53:25 -0500608 *
609 * Description:
610 * Not as serious as kauditd_hold_skb() as we still have a connected auditd,
611 * but for some reason we are having problems sending it audit records so
612 * queue the given record and attempt to resend.
613 */
Paul Mooref26d0432022-01-13 18:54:38 -0500614static void kauditd_retry_skb(struct sk_buff *skb, __always_unused int error)
Paul Moorec6480202016-11-29 16:53:25 -0500615{
Paul Mooref26d0432022-01-13 18:54:38 -0500616 if (!audit_backlog_limit ||
617 skb_queue_len(&audit_retry_queue) < audit_backlog_limit) {
618 skb_queue_tail(&audit_retry_queue, skb);
619 return;
620 }
621
622 /* we have to drop the record, send it via printk as a last effort */
623 kauditd_printk_skb(skb);
624 audit_log_lost("kauditd retry queue overflow");
625 kfree_skb(skb);
Paul Moorec6480202016-11-29 16:53:25 -0500626}
627
628/**
Paul Moore264d5092017-04-10 11:16:59 -0400629 * auditd_reset - Disconnect the auditd connection
Paul Moorec81be522017-06-12 09:35:24 -0400630 * @ac: auditd connection state
Paul Moore264d5092017-04-10 11:16:59 -0400631 *
632 * Description:
633 * Break the auditd/kauditd connection and move all the queued records into the
Paul Moorec81be522017-06-12 09:35:24 -0400634 * hold queue in case auditd reconnects. It is important to note that the @ac
635 * pointer should never be dereferenced inside this function as it may be NULL
636 * or invalid, you can only compare the memory address! If @ac is NULL then
637 * the connection will always be reset.
Paul Moore264d5092017-04-10 11:16:59 -0400638 */
Paul Moorec81be522017-06-12 09:35:24 -0400639static void auditd_reset(const struct auditd_connection *ac)
Paul Moore264d5092017-04-10 11:16:59 -0400640{
Paul Moore48d0e022017-05-02 10:16:05 -0400641 unsigned long flags;
Paul Moore264d5092017-04-10 11:16:59 -0400642 struct sk_buff *skb;
Paul Moore48d0e022017-05-02 10:16:05 -0400643 struct auditd_connection *ac_old;
Paul Moore264d5092017-04-10 11:16:59 -0400644
645 /* if it isn't already broken, break the connection */
Paul Moore48d0e022017-05-02 10:16:05 -0400646 spin_lock_irqsave(&auditd_conn_lock, flags);
647 ac_old = rcu_dereference_protected(auditd_conn,
648 lockdep_is_held(&auditd_conn_lock));
Paul Moorec81be522017-06-12 09:35:24 -0400649 if (ac && ac != ac_old) {
650 /* someone already registered a new auditd connection */
651 spin_unlock_irqrestore(&auditd_conn_lock, flags);
652 return;
653 }
Paul Moore48d0e022017-05-02 10:16:05 -0400654 rcu_assign_pointer(auditd_conn, NULL);
655 spin_unlock_irqrestore(&auditd_conn_lock, flags);
656
657 if (ac_old)
658 call_rcu(&ac_old->rcu, auditd_conn_free);
Paul Moore264d5092017-04-10 11:16:59 -0400659
Paul Moorecd33f5f2017-06-12 11:53:09 -0400660 /* flush the retry queue to the hold queue, but don't touch the main
661 * queue since we need to process that normally for multicast */
Paul Moore264d5092017-04-10 11:16:59 -0400662 while ((skb = skb_dequeue(&audit_retry_queue)))
Paul Mooref26d0432022-01-13 18:54:38 -0500663 kauditd_hold_skb(skb, -ECONNREFUSED);
Paul Moore264d5092017-04-10 11:16:59 -0400664}
665
666/**
Paul Moore5b523302017-03-21 11:26:35 -0400667 * auditd_send_unicast_skb - Send a record via unicast to auditd
668 * @skb: audit record
Paul Moorec6480202016-11-29 16:53:25 -0500669 *
670 * Description:
Paul Moore5b523302017-03-21 11:26:35 -0400671 * Send a skb to the audit daemon, returns positive/zero values on success and
672 * negative values on failure; in all cases the skb will be consumed by this
673 * function. If the send results in -ECONNREFUSED the connection with auditd
674 * will be reset. This function may sleep so callers should not hold any locks
675 * where this would cause a problem.
Paul Moorec6480202016-11-29 16:53:25 -0500676 */
Paul Moore5b523302017-03-21 11:26:35 -0400677static int auditd_send_unicast_skb(struct sk_buff *skb)
Paul Moorec6480202016-11-29 16:53:25 -0500678{
Paul Moore5b523302017-03-21 11:26:35 -0400679 int rc;
680 u32 portid;
681 struct net *net;
682 struct sock *sk;
Paul Moore48d0e022017-05-02 10:16:05 -0400683 struct auditd_connection *ac;
Paul Moorec6480202016-11-29 16:53:25 -0500684
Paul Moore5b523302017-03-21 11:26:35 -0400685 /* NOTE: we can't call netlink_unicast while in the RCU section so
686 * take a reference to the network namespace and grab local
687 * copies of the namespace, the sock, and the portid; the
688 * namespace and sock aren't going to go away while we hold a
689 * reference and if the portid does become invalid after the RCU
690 * section netlink_unicast() should safely return an error */
691
692 rcu_read_lock();
Paul Moore48d0e022017-05-02 10:16:05 -0400693 ac = rcu_dereference(auditd_conn);
694 if (!ac) {
Paul Moore5b523302017-03-21 11:26:35 -0400695 rcu_read_unlock();
Shu Wangb0659ae2017-07-18 14:37:24 +0800696 kfree_skb(skb);
Paul Moore5b523302017-03-21 11:26:35 -0400697 rc = -ECONNREFUSED;
698 goto err;
Richard Guy Briggs533c7b62016-12-13 10:03:01 -0500699 }
Paul Moore48d0e022017-05-02 10:16:05 -0400700 net = get_net(ac->net);
Paul Moore5b523302017-03-21 11:26:35 -0400701 sk = audit_get_sk(net);
Paul Moore48d0e022017-05-02 10:16:05 -0400702 portid = ac->portid;
Paul Moore5b523302017-03-21 11:26:35 -0400703 rcu_read_unlock();
Paul Moorec6480202016-11-29 16:53:25 -0500704
Paul Moore5b523302017-03-21 11:26:35 -0400705 rc = netlink_unicast(sk, skb, portid, 0);
706 put_net(net);
707 if (rc < 0)
708 goto err;
709
710 return rc;
711
712err:
Paul Moorec81be522017-06-12 09:35:24 -0400713 if (ac && rc == -ECONNREFUSED)
714 auditd_reset(ac);
Paul Moore5b523302017-03-21 11:26:35 -0400715 return rc;
Paul Moorec6480202016-11-29 16:53:25 -0500716}
717
718/**
Paul Moore5b523302017-03-21 11:26:35 -0400719 * kauditd_send_queue - Helper for kauditd_thread to flush skb queues
720 * @sk: the sending sock
721 * @portid: the netlink destination
722 * @queue: the skb queue to process
723 * @retry_limit: limit on number of netlink unicast failures
724 * @skb_hook: per-skb hook for additional processing
725 * @err_hook: hook called if the skb fails the netlink unicast send
726 *
727 * Description:
728 * Run through the given queue and attempt to send the audit records to auditd,
729 * returns zero on success, negative values on failure. It is up to the caller
730 * to ensure that the @sk is valid for the duration of this function.
731 *
Paul Moorec6480202016-11-29 16:53:25 -0500732 */
Paul Moore5b523302017-03-21 11:26:35 -0400733static int kauditd_send_queue(struct sock *sk, u32 portid,
734 struct sk_buff_head *queue,
735 unsigned int retry_limit,
736 void (*skb_hook)(struct sk_buff *skb),
Paul Mooref26d0432022-01-13 18:54:38 -0500737 void (*err_hook)(struct sk_buff *skb, int error))
Paul Moorec6480202016-11-29 16:53:25 -0500738{
Paul Moore5b523302017-03-21 11:26:35 -0400739 int rc = 0;
Paul Mooref26d0432022-01-13 18:54:38 -0500740 struct sk_buff *skb = NULL;
741 struct sk_buff *skb_tail;
Paul Mooref4b3ee32021-12-09 11:46:07 -0500742 unsigned int failed = 0;
Paul Moorec6480202016-11-29 16:53:25 -0500743
Paul Moore5b523302017-03-21 11:26:35 -0400744 /* NOTE: kauditd_thread takes care of all our locking, we just use
745 * the netlink info passed to us (e.g. sk and portid) */
Paul Moore6c54e782016-11-29 16:53:26 -0500746
Paul Mooref26d0432022-01-13 18:54:38 -0500747 skb_tail = skb_peek_tail(queue);
748 while ((skb != skb_tail) && (skb = skb_dequeue(queue))) {
Paul Moore5b523302017-03-21 11:26:35 -0400749 /* call the skb_hook for each skb we touch */
750 if (skb_hook)
751 (*skb_hook)(skb);
752
753 /* can we send to anyone via unicast? */
754 if (!sk) {
755 if (err_hook)
Paul Mooref26d0432022-01-13 18:54:38 -0500756 (*err_hook)(skb, -ECONNREFUSED);
Paul Moore5b523302017-03-21 11:26:35 -0400757 continue;
758 }
759
Paul Mooref4b3ee32021-12-09 11:46:07 -0500760retry:
Paul Moore5b523302017-03-21 11:26:35 -0400761 /* grab an extra skb reference in case of error */
762 skb_get(skb);
763 rc = netlink_unicast(sk, skb, portid, 0);
764 if (rc < 0) {
Paul Mooref4b3ee32021-12-09 11:46:07 -0500765 /* send failed - try a few times unless fatal error */
Paul Moore5b523302017-03-21 11:26:35 -0400766 if (++failed >= retry_limit ||
767 rc == -ECONNREFUSED || rc == -EPERM) {
Paul Moore5b523302017-03-21 11:26:35 -0400768 sk = NULL;
769 if (err_hook)
Paul Mooref26d0432022-01-13 18:54:38 -0500770 (*err_hook)(skb, rc);
Paul Mooref4b3ee32021-12-09 11:46:07 -0500771 if (rc == -EAGAIN)
772 rc = 0;
773 /* continue to drain the queue */
Paul Moore5b523302017-03-21 11:26:35 -0400774 continue;
775 } else
Paul Mooref4b3ee32021-12-09 11:46:07 -0500776 goto retry;
Paul Moore5b523302017-03-21 11:26:35 -0400777 } else {
Paul Mooref4b3ee32021-12-09 11:46:07 -0500778 /* skb sent - drop the extra reference and continue */
Paul Moore5b523302017-03-21 11:26:35 -0400779 consume_skb(skb);
780 failed = 0;
781 }
Paul Moorec6480202016-11-29 16:53:25 -0500782 }
783
Paul Moore5b523302017-03-21 11:26:35 -0400784 return (rc >= 0 ? 0 : rc);
Eric Parisf3d357b2008-04-18 10:02:28 -0400785}
786
Richard Guy Briggsb551d1d2013-01-24 13:15:10 -0500787/*
Paul Moorec6480202016-11-29 16:53:25 -0500788 * kauditd_send_multicast_skb - Send a record to any multicast listeners
789 * @skb: audit record
Richard Guy Briggs451f9212014-04-22 21:31:57 -0400790 *
Paul Moorec6480202016-11-29 16:53:25 -0500791 * Description:
Paul Moore5b523302017-03-21 11:26:35 -0400792 * Write a multicast message to anyone listening in the initial network
793 * namespace. This function doesn't consume an skb as might be expected since
794 * it has to copy it anyways.
Richard Guy Briggs451f9212014-04-22 21:31:57 -0400795 */
Paul Moorec6480202016-11-29 16:53:25 -0500796static void kauditd_send_multicast_skb(struct sk_buff *skb)
Richard Guy Briggs451f9212014-04-22 21:31:57 -0400797{
Paul Moorec6480202016-11-29 16:53:25 -0500798 struct sk_buff *copy;
Paul Moore5b523302017-03-21 11:26:35 -0400799 struct sock *sock = audit_get_sk(&init_net);
Paul Moorec6480202016-11-29 16:53:25 -0500800 struct nlmsghdr *nlh;
Richard Guy Briggs451f9212014-04-22 21:31:57 -0400801
Paul Moore5b523302017-03-21 11:26:35 -0400802 /* NOTE: we are not taking an additional reference for init_net since
803 * we don't have to worry about it going away */
804
Richard Guy Briggs7f74ecd72014-04-22 21:31:58 -0400805 if (!netlink_has_listeners(sock, AUDIT_NLGRP_READLOG))
806 return;
807
Richard Guy Briggs451f9212014-04-22 21:31:57 -0400808 /*
809 * The seemingly wasteful skb_copy() rather than bumping the refcount
810 * using skb_get() is necessary because non-standard mods are made to
811 * the skb by the original kaudit unicast socket send routine. The
812 * existing auditd daemon assumes this breakage. Fixing this would
813 * require co-ordinating a change in the established protocol between
814 * the kaudit kernel subsystem and the auditd userspace code. There is
815 * no reason for new multicast clients to continue with this
816 * non-compliance.
817 */
Paul Moorec6480202016-11-29 16:53:25 -0500818 copy = skb_copy(skb, GFP_KERNEL);
Richard Guy Briggs451f9212014-04-22 21:31:57 -0400819 if (!copy)
820 return;
Paul Moorec6480202016-11-29 16:53:25 -0500821 nlh = nlmsg_hdr(copy);
822 nlh->nlmsg_len = skb->len;
Richard Guy Briggs451f9212014-04-22 21:31:57 -0400823
Paul Moorec6480202016-11-29 16:53:25 -0500824 nlmsg_multicast(sock, copy, 0, AUDIT_NLGRP_READLOG, GFP_KERNEL);
Richard Guy Briggs451f9212014-04-22 21:31:57 -0400825}
826
Paul Moorec6480202016-11-29 16:53:25 -0500827/**
Paul Moore5b523302017-03-21 11:26:35 -0400828 * kauditd_thread - Worker thread to send audit records to userspace
829 * @dummy: unused
Richard Guy Briggsb551d1d2013-01-24 13:15:10 -0500830 */
Adrian Bunk97a41e22006-01-08 01:02:17 -0800831static int kauditd_thread(void *dummy)
David Woodhouseb7d11252005-05-19 10:56:58 +0100832{
Paul Moorec6480202016-11-29 16:53:25 -0500833 int rc;
Paul Moore5b523302017-03-21 11:26:35 -0400834 u32 portid = 0;
835 struct net *net = NULL;
836 struct sock *sk = NULL;
Paul Moore48d0e022017-05-02 10:16:05 -0400837 struct auditd_connection *ac;
Paul Moore4aa838722016-11-29 16:53:24 -0500838
Paul Moorec6480202016-11-29 16:53:25 -0500839#define UNICAST_RETRIES 5
Paul Moorec6480202016-11-29 16:53:25 -0500840
Rafael J. Wysocki83144182007-07-17 04:03:35 -0700841 set_freezable();
Andrew Morton4899b8b2006-10-06 00:43:48 -0700842 while (!kthread_should_stop()) {
Paul Moore5b523302017-03-21 11:26:35 -0400843 /* NOTE: see the lock comments in auditd_send_unicast_skb() */
844 rcu_read_lock();
Paul Moore48d0e022017-05-02 10:16:05 -0400845 ac = rcu_dereference(auditd_conn);
846 if (!ac) {
Paul Moore5b523302017-03-21 11:26:35 -0400847 rcu_read_unlock();
848 goto main_queue;
849 }
Paul Moore48d0e022017-05-02 10:16:05 -0400850 net = get_net(ac->net);
Paul Moore5b523302017-03-21 11:26:35 -0400851 sk = audit_get_sk(net);
Paul Moore48d0e022017-05-02 10:16:05 -0400852 portid = ac->portid;
Paul Moore5b523302017-03-21 11:26:35 -0400853 rcu_read_unlock();
Eric Parisf3d357b2008-04-18 10:02:28 -0400854
Paul Moorec6480202016-11-29 16:53:25 -0500855 /* attempt to flush the hold queue */
Paul Moore5b523302017-03-21 11:26:35 -0400856 rc = kauditd_send_queue(sk, portid,
857 &audit_hold_queue, UNICAST_RETRIES,
858 NULL, kauditd_rehold_skb);
Yunfeng Yec34c78d2019-10-23 21:27:34 +0800859 if (rc < 0) {
Paul Moore5b523302017-03-21 11:26:35 -0400860 sk = NULL;
Paul Moorec81be522017-06-12 09:35:24 -0400861 auditd_reset(ac);
Paul Moore5b523302017-03-21 11:26:35 -0400862 goto main_queue;
David Woodhouseb7d11252005-05-19 10:56:58 +0100863 }
Richard Guy Briggs3320c512013-01-24 13:15:11 -0500864
Paul Moorec6480202016-11-29 16:53:25 -0500865 /* attempt to flush the retry queue */
Paul Moore5b523302017-03-21 11:26:35 -0400866 rc = kauditd_send_queue(sk, portid,
867 &audit_retry_queue, UNICAST_RETRIES,
868 NULL, kauditd_hold_skb);
Yunfeng Yec34c78d2019-10-23 21:27:34 +0800869 if (rc < 0) {
Paul Moore5b523302017-03-21 11:26:35 -0400870 sk = NULL;
Paul Moorec81be522017-06-12 09:35:24 -0400871 auditd_reset(ac);
Paul Moore5b523302017-03-21 11:26:35 -0400872 goto main_queue;
Paul Moorec6480202016-11-29 16:53:25 -0500873 }
874
Paul Moore5b523302017-03-21 11:26:35 -0400875main_queue:
876 /* process the main queue - do the multicast send and attempt
877 * unicast, dump failed record sends to the retry queue; if
878 * sk == NULL due to previous failures we will just do the
Paul Moorec81be522017-06-12 09:35:24 -0400879 * multicast send and move the record to the hold queue */
Paul Moore264d5092017-04-10 11:16:59 -0400880 rc = kauditd_send_queue(sk, portid, &audit_queue, 1,
881 kauditd_send_multicast_skb,
Paul Moorec81be522017-06-12 09:35:24 -0400882 (sk ?
883 kauditd_retry_skb : kauditd_hold_skb));
884 if (ac && rc < 0)
885 auditd_reset(ac);
Paul Moore264d5092017-04-10 11:16:59 -0400886 sk = NULL;
Paul Moore4aa838722016-11-29 16:53:24 -0500887
Paul Moore5b523302017-03-21 11:26:35 -0400888 /* drop our netns reference, no auditd sends past this line */
889 if (net) {
890 put_net(net);
891 net = NULL;
Richard Guy Briggs3320c512013-01-24 13:15:11 -0500892 }
Paul Moore5b523302017-03-21 11:26:35 -0400893
894 /* we have processed all the queues so wake everyone */
895 wake_up(&audit_backlog_wait);
896
897 /* NOTE: we want to wake up if there is anything on the queue,
898 * regardless of if an auditd is connected, as we need to
899 * do the multicast send and rotate records from the
900 * main queue to the retry/hold queues */
901 wait_event_freezable(kauditd_wait,
902 (skb_queue_len(&audit_queue) ? 1 : 0));
David Woodhouseb7d11252005-05-19 10:56:58 +0100903 }
Paul Moorec6480202016-11-29 16:53:25 -0500904
Andrew Morton4899b8b2006-10-06 00:43:48 -0700905 return 0;
David Woodhouseb7d11252005-05-19 10:56:58 +0100906}
907
Paul Moore3054d062020-04-21 09:10:56 -0400908int audit_send_list_thread(void *_dest)
Al Viro9044e6b2006-05-22 01:09:24 -0400909{
910 struct audit_netlink_list *dest = _dest;
Al Viro9044e6b2006-05-22 01:09:24 -0400911 struct sk_buff *skb;
Paul Moore5b523302017-03-21 11:26:35 -0400912 struct sock *sk = audit_get_sk(dest->net);
Al Viro9044e6b2006-05-22 01:09:24 -0400913
914 /* wait for parent to finish and send an ACK */
Paul Moorece4236312018-02-20 09:52:38 -0500915 audit_ctl_lock();
916 audit_ctl_unlock();
Al Viro9044e6b2006-05-22 01:09:24 -0400917
918 while ((skb = __skb_dequeue(&dest->q)) != NULL)
Paul Moore5b523302017-03-21 11:26:35 -0400919 netlink_unicast(sk, skb, dest->portid, 0);
Al Viro9044e6b2006-05-22 01:09:24 -0400920
Paul Moore5b523302017-03-21 11:26:35 -0400921 put_net(dest->net);
Al Viro9044e6b2006-05-22 01:09:24 -0400922 kfree(dest);
923
924 return 0;
925}
926
Paul Moore45a06422017-05-02 10:16:05 -0400927struct sk_buff *audit_make_reply(int seq, int type, int done,
Stephen Hemmingerb8800aa2010-10-20 17:23:50 -0700928 int multi, const void *payload, int size)
Al Viro9044e6b2006-05-22 01:09:24 -0400929{
930 struct sk_buff *skb;
931 struct nlmsghdr *nlh;
Al Viro9044e6b2006-05-22 01:09:24 -0400932 void *data;
933 int flags = multi ? NLM_F_MULTI : 0;
934 int t = done ? NLMSG_DONE : type;
935
Eric Parisee080e62009-06-11 14:31:35 -0400936 skb = nlmsg_new(size, GFP_KERNEL);
Al Viro9044e6b2006-05-22 01:09:24 -0400937 if (!skb)
938 return NULL;
939
Paul Moore45a06422017-05-02 10:16:05 -0400940 nlh = nlmsg_put(skb, 0, seq, t, size, flags);
David S. Millerc64e66c2012-06-26 21:45:21 -0700941 if (!nlh)
942 goto out_kfree_skb;
943 data = nlmsg_data(nlh);
Al Viro9044e6b2006-05-22 01:09:24 -0400944 memcpy(data, payload, size);
945 return skb;
946
David S. Millerc64e66c2012-06-26 21:45:21 -0700947out_kfree_skb:
948 kfree_skb(skb);
Al Viro9044e6b2006-05-22 01:09:24 -0400949 return NULL;
950}
951
Paul Moorea48b2842020-04-20 10:09:29 -0400952static void audit_free_reply(struct audit_reply *reply)
953{
954 if (!reply)
955 return;
956
Xu Wangc0720352020-08-26 04:00:22 +0000957 kfree_skb(reply->skb);
Paul Moorea48b2842020-04-20 10:09:29 -0400958 if (reply->net)
959 put_net(reply->net);
960 kfree(reply);
961}
962
Eric Parisf09ac9d2008-04-18 10:11:04 -0400963static int audit_send_reply_thread(void *arg)
964{
965 struct audit_reply *reply = (struct audit_reply *)arg;
966
Paul Moorece4236312018-02-20 09:52:38 -0500967 audit_ctl_lock();
968 audit_ctl_unlock();
Eric Parisf09ac9d2008-04-18 10:11:04 -0400969
970 /* Ignore failure. It'll only happen if the sender goes away,
971 because our timeout is set to infinite. */
Paul Moorea48b2842020-04-20 10:09:29 -0400972 netlink_unicast(audit_get_sk(reply->net), reply->skb, reply->portid, 0);
973 reply->skb = NULL;
974 audit_free_reply(reply);
Eric Parisf09ac9d2008-04-18 10:11:04 -0400975 return 0;
976}
Paul Moorec6480202016-11-29 16:53:25 -0500977
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700978/**
979 * audit_send_reply - send an audit reply message via netlink
Eric W. Biedermand211f1772014-03-08 15:31:54 -0800980 * @request_skb: skb of request we are replying to (used to target the reply)
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700981 * @seq: sequence number
982 * @type: audit message type
983 * @done: done (last) flag
984 * @multi: multi-part message flag
985 * @payload: payload data
986 * @size: payload size
987 *
Paul Moorea48b2842020-04-20 10:09:29 -0400988 * Allocates a skb, builds the netlink message, and sends it to the port id.
Randy Dunlapb0dd25a2005-09-13 12:47:11 -0700989 */
Eric W. Biederman6f285b12014-02-28 19:44:55 -0800990static void audit_send_reply(struct sk_buff *request_skb, int seq, int type, int done,
Richard Guy Briggsf9441632013-08-14 11:32:45 -0400991 int multi, const void *payload, int size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992{
Eric Parisf09ac9d2008-04-18 10:11:04 -0400993 struct task_struct *tsk;
Paul Moorea48b2842020-04-20 10:09:29 -0400994 struct audit_reply *reply;
Eric Parisf09ac9d2008-04-18 10:11:04 -0400995
Paul Moorea48b2842020-04-20 10:09:29 -0400996 reply = kzalloc(sizeof(*reply), GFP_KERNEL);
Eric Parisf09ac9d2008-04-18 10:11:04 -0400997 if (!reply)
998 return;
999
Paul Moorea48b2842020-04-20 10:09:29 -04001000 reply->skb = audit_make_reply(seq, type, done, multi, payload, size);
1001 if (!reply->skb)
1002 goto err;
1003 reply->net = get_net(sock_net(NETLINK_CB(request_skb).sk));
Paul Moore45a06422017-05-02 10:16:05 -04001004 reply->portid = NETLINK_CB(request_skb).portid;
Eric Parisf09ac9d2008-04-18 10:11:04 -04001005
1006 tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
Paul Moorea48b2842020-04-20 10:09:29 -04001007 if (IS_ERR(tsk))
1008 goto err;
1009
1010 return;
1011
1012err:
1013 audit_free_reply(reply);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001014}
1015
1016/*
1017 * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
1018 * control messages.
1019 */
Darrel Goeddelc7bdb542006-06-27 13:26:11 -07001020static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001021{
1022 int err = 0;
1023
Richard Guy Briggs5a3cb3b2013-08-16 00:04:46 -04001024 /* Only support initial user namespace for now. */
Eric Parisaa4af832014-03-30 19:07:54 -04001025 /*
1026 * We return ECONNREFUSED because it tricks userspace into thinking
1027 * that audit was not configured into the kernel. Lots of users
1028 * configure their PAM stack (because that's what the distro does)
1029 * to reject login if unable to send messages to audit. If we return
1030 * ECONNREFUSED the PAM stack thinks the kernel does not have audit
1031 * configured in and will let login proceed. If we return EPERM
1032 * userspace will reject all logins. This should be removed when we
1033 * support non init namespaces!!
1034 */
Linus Torvalds0b747172014-04-12 12:38:53 -07001035 if (current_user_ns() != &init_user_ns)
Eric Parisaa4af832014-03-30 19:07:54 -04001036 return -ECONNREFUSED;
Eric W. Biederman34e36d8e2012-09-10 23:20:20 -07001037
Linus Torvalds1da177e2005-04-16 15:20:36 -07001038 switch (msg_type) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001039 case AUDIT_LIST:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040 case AUDIT_ADD:
1041 case AUDIT_DEL:
Eric Paris18900902013-04-18 19:16:36 -04001042 return -EOPNOTSUPP;
1043 case AUDIT_GET:
1044 case AUDIT_SET:
Eric Parisb0fed402013-05-22 12:54:49 -04001045 case AUDIT_GET_FEATURE:
1046 case AUDIT_SET_FEATURE:
Eric Paris18900902013-04-18 19:16:36 -04001047 case AUDIT_LIST_RULES:
1048 case AUDIT_ADD_RULE:
Amy Griffis93315ed2006-02-07 12:05:27 -05001049 case AUDIT_DEL_RULE:
Steve Grubbc2f0c7c2005-05-06 12:38:39 +01001050 case AUDIT_SIGNAL_INFO:
Miloslav Trmac522ed772007-07-15 23:40:56 -07001051 case AUDIT_TTY_GET:
1052 case AUDIT_TTY_SET:
Al Viro74c3cbe2007-07-22 08:04:18 -04001053 case AUDIT_TRIM:
1054 case AUDIT_MAKE_EQUIV:
Richard Guy Briggs5a3cb3b2013-08-16 00:04:46 -04001055 /* Only support auditd and auditctl in initial pid namespace
1056 * for now. */
Ameen Ali5985de62015-02-23 15:38:00 -05001057 if (task_active_pid_ns(current) != &init_pid_ns)
Richard Guy Briggs5a3cb3b2013-08-16 00:04:46 -04001058 return -EPERM;
1059
Eric W. Biederman90f62cf32014-04-23 14:29:27 -07001060 if (!netlink_capable(skb, CAP_AUDIT_CONTROL))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001061 err = -EPERM;
1062 break;
Steve Grubb05474102005-05-21 00:18:37 +01001063 case AUDIT_USER:
Robert P. J. Day039b6b32007-05-08 00:29:20 -07001064 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
1065 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
Eric W. Biederman90f62cf32014-04-23 14:29:27 -07001066 if (!netlink_capable(skb, CAP_AUDIT_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067 err = -EPERM;
1068 break;
1069 default: /* bad msg */
1070 err = -EINVAL;
1071 }
1072
1073 return err;
1074}
1075
Richard Guy Briggs626abcd2019-01-18 17:42:48 -05001076static void audit_log_common_recv_msg(struct audit_context *context,
1077 struct audit_buffer **ab, u16 msg_type)
Eric Paris50397bd2008-01-07 18:14:19 -05001078{
Eric Parisdc9eb692013-04-19 13:23:09 -04001079 uid_t uid = from_kuid(&init_user_ns, current_uid());
Richard Guy Briggsf1dc4862013-12-11 13:52:26 -05001080 pid_t pid = task_tgid_nr(current);
Eric Paris50397bd2008-01-07 18:14:19 -05001081
Tyler Hicks0868a5e2013-07-25 18:02:55 -07001082 if (!audit_enabled && msg_type != AUDIT_USER_AVC) {
Eric Paris50397bd2008-01-07 18:14:19 -05001083 *ab = NULL;
Paul Moore233a6862015-11-04 08:23:52 -05001084 return;
Eric Paris50397bd2008-01-07 18:14:19 -05001085 }
1086
Richard Guy Briggs626abcd2019-01-18 17:42:48 -05001087 *ab = audit_log_start(context, GFP_KERNEL, msg_type);
Kees Cook0644ec02013-01-11 14:32:07 -08001088 if (unlikely(!*ab))
Paul Moore233a6862015-11-04 08:23:52 -05001089 return;
Richard Guy Briggsa2c97da2018-11-16 16:30:10 -05001090 audit_log_format(*ab, "pid=%d uid=%u ", pid, uid);
Eric Paris4d3fb702013-04-30 09:53:34 -04001091 audit_log_session_info(*ab);
Eric Parisb122c372013-04-19 15:00:33 -04001092 audit_log_task_context(*ab);
Eric Paris50397bd2008-01-07 18:14:19 -05001093}
1094
Richard Guy Briggs626abcd2019-01-18 17:42:48 -05001095static inline void audit_log_user_recv_msg(struct audit_buffer **ab,
1096 u16 msg_type)
1097{
1098 audit_log_common_recv_msg(NULL, ab, msg_type);
1099}
1100
Xiu Jianfeng54609322022-06-11 17:23:04 +08001101static int is_audit_feature_set(int i)
Eric Parisb0fed402013-05-22 12:54:49 -04001102{
1103 return af.features & AUDIT_FEATURE_TO_MASK(i);
1104}
1105
1106
1107static int audit_get_feature(struct sk_buff *skb)
1108{
1109 u32 seq;
1110
1111 seq = nlmsg_hdr(skb)->nlmsg_seq;
1112
Richard Guy Briggs9ef915142014-08-24 20:37:52 -04001113 audit_send_reply(skb, seq, AUDIT_GET_FEATURE, 0, 0, &af, sizeof(af));
Eric Parisb0fed402013-05-22 12:54:49 -04001114
1115 return 0;
1116}
1117
1118static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature,
1119 u32 old_lock, u32 new_lock, int res)
1120{
1121 struct audit_buffer *ab;
1122
Gao fengb6c50fe2013-11-01 19:34:43 +08001123 if (audit_enabled == AUDIT_OFF)
1124 return;
Paul Moore2a1fe212018-11-26 18:40:07 -05001125
Richard Guy Briggscdfb6b32018-05-12 21:58:20 -04001126 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_FEATURE_CHANGE);
Richard Guy Briggs23138ea2018-02-21 04:30:07 -05001127 if (!ab)
1128 return;
Paul Moore2a1fe212018-11-26 18:40:07 -05001129 audit_log_task_info(ab);
Richard Guy Briggs897f1ac2014-10-30 11:22:53 -04001130 audit_log_format(ab, " feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d",
Eric Parisb0fed402013-05-22 12:54:49 -04001131 audit_feature_names[which], !!old_feature, !!new_feature,
1132 !!old_lock, !!new_lock, res);
1133 audit_log_end(ab);
1134}
1135
Paul Moore75612522020-02-24 16:38:57 -05001136static int audit_set_feature(struct audit_features *uaf)
Eric Parisb0fed402013-05-22 12:54:49 -04001137{
Eric Parisb0fed402013-05-22 12:54:49 -04001138 int i;
1139
Fabian Frederick6eed9b22014-06-03 22:05:10 +02001140 BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > ARRAY_SIZE(audit_feature_names));
Eric Parisb0fed402013-05-22 12:54:49 -04001141
1142 /* if there is ever a version 2 we should handle that here */
1143
1144 for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
1145 u32 feature = AUDIT_FEATURE_TO_MASK(i);
1146 u32 old_feature, new_feature, old_lock, new_lock;
1147
1148 /* if we are not changing this feature, move along */
1149 if (!(feature & uaf->mask))
1150 continue;
1151
1152 old_feature = af.features & feature;
1153 new_feature = uaf->features & feature;
1154 new_lock = (uaf->lock | af.lock) & feature;
1155 old_lock = af.lock & feature;
1156
1157 /* are we changing a locked feature? */
Gao feng4547b3b2013-11-01 19:34:44 +08001158 if (old_lock && (new_feature != old_feature)) {
Eric Parisb0fed402013-05-22 12:54:49 -04001159 audit_log_feature_change(i, old_feature, new_feature,
1160 old_lock, new_lock, 0);
1161 return -EPERM;
1162 }
1163 }
1164 /* nothing invalid, do the changes */
1165 for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
1166 u32 feature = AUDIT_FEATURE_TO_MASK(i);
1167 u32 old_feature, new_feature, old_lock, new_lock;
1168
1169 /* if we are not changing this feature, move along */
1170 if (!(feature & uaf->mask))
1171 continue;
1172
1173 old_feature = af.features & feature;
1174 new_feature = uaf->features & feature;
1175 old_lock = af.lock & feature;
1176 new_lock = (uaf->lock | af.lock) & feature;
1177
1178 if (new_feature != old_feature)
1179 audit_log_feature_change(i, old_feature, new_feature,
1180 old_lock, new_lock, 1);
1181
1182 if (new_feature)
1183 af.features |= feature;
1184 else
1185 af.features &= ~feature;
1186 af.lock |= new_lock;
1187 }
1188
1189 return 0;
1190}
1191
Paul Mooreb6c7c112017-05-02 10:16:05 -04001192static int audit_replace(struct pid *pid)
Richard Guy Briggs133e1e52016-01-25 18:04:15 -05001193{
Paul Mooreb6c7c112017-05-02 10:16:05 -04001194 pid_t pvnr;
Paul Moore5b523302017-03-21 11:26:35 -04001195 struct sk_buff *skb;
Richard Guy Briggs133e1e52016-01-25 18:04:15 -05001196
Paul Mooreb6c7c112017-05-02 10:16:05 -04001197 pvnr = pid_vnr(pid);
1198 skb = audit_make_reply(0, AUDIT_REPLACE, 0, 0, &pvnr, sizeof(pvnr));
Richard Guy Briggs133e1e52016-01-25 18:04:15 -05001199 if (!skb)
1200 return -ENOMEM;
Paul Moore5b523302017-03-21 11:26:35 -04001201 return auditd_send_unicast_skb(skb);
Richard Guy Briggs133e1e52016-01-25 18:04:15 -05001202}
1203
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1205{
Eric Parisdc9eb692013-04-19 13:23:09 -04001206 u32 seq;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001207 void *data;
Paul Moore75612522020-02-24 16:38:57 -05001208 int data_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001209 int err;
Steve Grubbc0404992005-05-13 18:17:42 +01001210 struct audit_buffer *ab;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001211 u16 msg_type = nlh->nlmsg_type;
Al Viroe1396062006-05-25 10:19:47 -04001212 struct audit_sig_info *sig_data;
Eric Paris50397bd2008-01-07 18:14:19 -05001213 char *ctx = NULL;
Al Viroe1396062006-05-25 10:19:47 -04001214 u32 len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001215
Darrel Goeddelc7bdb542006-06-27 13:26:11 -07001216 err = audit_netlink_ok(skb, msg_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001217 if (err)
1218 return err;
1219
Linus Torvalds1da177e2005-04-16 15:20:36 -07001220 seq = nlh->nlmsg_seq;
David S. Millerc64e66c2012-06-26 21:45:21 -07001221 data = nlmsg_data(nlh);
Paul Moore75612522020-02-24 16:38:57 -05001222 data_len = nlmsg_len(nlh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223
1224 switch (msg_type) {
Richard Guy Briggs09f883a2013-09-18 09:32:24 -04001225 case AUDIT_GET: {
1226 struct audit_status s;
1227 memset(&s, 0, sizeof(s));
Max Englanderb43870c2020-07-04 15:15:28 +00001228 s.enabled = audit_enabled;
1229 s.failure = audit_failure;
Paul Mooreb6c7c112017-05-02 10:16:05 -04001230 /* NOTE: use pid_vnr() so the PID is relative to the current
1231 * namespace */
Max Englanderb43870c2020-07-04 15:15:28 +00001232 s.pid = auditd_pid_vnr();
1233 s.rate_limit = audit_rate_limit;
1234 s.backlog_limit = audit_backlog_limit;
1235 s.lost = atomic_read(&audit_lost);
1236 s.backlog = skb_queue_len(&audit_queue);
1237 s.feature_bitmap = AUDIT_FEATURE_BITMAP_ALL;
1238 s.backlog_wait_time = audit_backlog_wait_time;
1239 s.backlog_wait_time_actual = atomic_read(&audit_backlog_wait_time_actual);
Eric W. Biederman6f285b12014-02-28 19:44:55 -08001240 audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &s, sizeof(s));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241 break;
Richard Guy Briggs09f883a2013-09-18 09:32:24 -04001242 }
1243 case AUDIT_SET: {
1244 struct audit_status s;
1245 memset(&s, 0, sizeof(s));
1246 /* guard against past and future API changes */
Paul Moore75612522020-02-24 16:38:57 -05001247 memcpy(&s, data, min_t(size_t, sizeof(s), data_len));
Richard Guy Briggs09f883a2013-09-18 09:32:24 -04001248 if (s.mask & AUDIT_STATUS_ENABLED) {
1249 err = audit_set_enabled(s.enabled);
zhangxiliang20c6aaa2008-07-31 10:11:19 +08001250 if (err < 0)
1251 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001252 }
Richard Guy Briggs09f883a2013-09-18 09:32:24 -04001253 if (s.mask & AUDIT_STATUS_FAILURE) {
1254 err = audit_set_failure(s.failure);
zhangxiliang20c6aaa2008-07-31 10:11:19 +08001255 if (err < 0)
1256 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001257 }
Richard Guy Briggs09f883a2013-09-18 09:32:24 -04001258 if (s.mask & AUDIT_STATUS_PID) {
Paul Mooreb6c7c112017-05-02 10:16:05 -04001259 /* NOTE: we are using the vnr PID functions below
1260 * because the s.pid value is relative to the
1261 * namespace of the caller; at present this
1262 * doesn't matter much since you can really only
1263 * run auditd from the initial pid namespace, but
1264 * something to keep in mind if this changes */
1265 pid_t new_pid = s.pid;
Paul Moore5b523302017-03-21 11:26:35 -04001266 pid_t auditd_pid;
Paul Mooreb6c7c112017-05-02 10:16:05 -04001267 struct pid *req_pid = task_tgid(current);
1268
Steve Grubb33e8a902017-10-17 18:29:22 -04001269 /* Sanity check - PID values must match. Setting
1270 * pid to 0 is how auditd ends auditing. */
1271 if (new_pid && (new_pid != pid_vnr(req_pid)))
Paul Mooreb6c7c112017-05-02 10:16:05 -04001272 return -EINVAL;
Eric Paris1a6b9f22008-01-07 17:09:31 -05001273
Paul Moore5b523302017-03-21 11:26:35 -04001274 /* test the auditd connection */
Paul Mooreb6c7c112017-05-02 10:16:05 -04001275 audit_replace(req_pid);
Paul Moore5b523302017-03-21 11:26:35 -04001276
Paul Moore48d0e022017-05-02 10:16:05 -04001277 auditd_pid = auditd_pid_vnr();
Steve Grubb33e8a902017-10-17 18:29:22 -04001278 if (auditd_pid) {
1279 /* replacing a healthy auditd is not allowed */
1280 if (new_pid) {
1281 audit_log_config_change("audit_pid",
1282 new_pid, auditd_pid, 0);
1283 return -EEXIST;
1284 }
1285 /* only current auditd can unregister itself */
1286 if (pid_vnr(req_pid) != auditd_pid) {
1287 audit_log_config_change("audit_pid",
1288 new_pid, auditd_pid, 0);
1289 return -EACCES;
1290 }
Richard Guy Briggs935c9e72016-01-25 18:04:15 -05001291 }
Paul Moore5b523302017-03-21 11:26:35 -04001292
Richard Guy Briggs533c7b62016-12-13 10:03:01 -05001293 if (new_pid) {
Paul Moore5b523302017-03-21 11:26:35 -04001294 /* register a new auditd connection */
Paul Moore48d0e022017-05-02 10:16:05 -04001295 err = auditd_set(req_pid,
1296 NETLINK_CB(skb).portid,
1297 sock_net(NETLINK_CB(skb).sk));
1298 if (audit_enabled != AUDIT_OFF)
1299 audit_log_config_change("audit_pid",
1300 new_pid,
1301 auditd_pid,
1302 err ? 0 : 1);
1303 if (err)
1304 return err;
1305
Paul Moore5b523302017-03-21 11:26:35 -04001306 /* try to process any backlog */
1307 wake_up_interruptible(&kauditd_wait);
Paul Moore48d0e022017-05-02 10:16:05 -04001308 } else {
1309 if (audit_enabled != AUDIT_OFF)
1310 audit_log_config_change("audit_pid",
1311 new_pid,
1312 auditd_pid, 1);
1313
Paul Moore5b523302017-03-21 11:26:35 -04001314 /* unregister the auditd connection */
Paul Moorec81be522017-06-12 09:35:24 -04001315 auditd_reset(NULL);
Paul Moore48d0e022017-05-02 10:16:05 -04001316 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001317 }
Richard Guy Briggs09f883a2013-09-18 09:32:24 -04001318 if (s.mask & AUDIT_STATUS_RATE_LIMIT) {
1319 err = audit_set_rate_limit(s.rate_limit);
zhangxiliang20c6aaa2008-07-31 10:11:19 +08001320 if (err < 0)
1321 return err;
1322 }
Richard Guy Briggs51cc83f2013-09-18 11:55:12 -04001323 if (s.mask & AUDIT_STATUS_BACKLOG_LIMIT) {
Richard Guy Briggs09f883a2013-09-18 09:32:24 -04001324 err = audit_set_backlog_limit(s.backlog_limit);
Richard Guy Briggs51cc83f2013-09-18 11:55:12 -04001325 if (err < 0)
1326 return err;
1327 }
Eric Paris3f0c5fa2014-01-13 16:49:28 -05001328 if (s.mask & AUDIT_STATUS_BACKLOG_WAIT_TIME) {
1329 if (sizeof(s) > (size_t)nlh->nlmsg_len)
1330 return -EINVAL;
Pranith Kumar724e7bf2015-03-11 14:08:19 -04001331 if (s.backlog_wait_time > 10*AUDIT_BACKLOG_WAIT_TIME)
Eric Paris3f0c5fa2014-01-13 16:49:28 -05001332 return -EINVAL;
1333 err = audit_set_backlog_wait_time(s.backlog_wait_time);
1334 if (err < 0)
1335 return err;
Richard Guy Briggs51cc83f2013-09-18 11:55:12 -04001336 }
Richard Guy Briggs92c82e82017-01-13 03:26:29 -05001337 if (s.mask == AUDIT_STATUS_LOST) {
1338 u32 lost = atomic_xchg(&audit_lost, 0);
1339
1340 audit_log_config_change("lost", 0, lost, 1);
1341 return lost;
1342 }
Max Englanderb43870c2020-07-04 15:15:28 +00001343 if (s.mask == AUDIT_STATUS_BACKLOG_WAIT_TIME_ACTUAL) {
1344 u32 actual = atomic_xchg(&audit_backlog_wait_time_actual, 0);
1345
1346 audit_log_config_change("backlog_wait_time_actual", 0, actual, 1);
1347 return actual;
1348 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349 break;
Richard Guy Briggs09f883a2013-09-18 09:32:24 -04001350 }
Eric Parisb0fed402013-05-22 12:54:49 -04001351 case AUDIT_GET_FEATURE:
1352 err = audit_get_feature(skb);
1353 if (err)
1354 return err;
1355 break;
1356 case AUDIT_SET_FEATURE:
Paul Moore75612522020-02-24 16:38:57 -05001357 if (data_len < sizeof(struct audit_features))
1358 return -EINVAL;
1359 err = audit_set_feature(data);
Eric Parisb0fed402013-05-22 12:54:49 -04001360 if (err)
1361 return err;
1362 break;
Steve Grubb05474102005-05-21 00:18:37 +01001363 case AUDIT_USER:
Robert P. J. Day039b6b32007-05-08 00:29:20 -07001364 case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
1365 case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
David Woodhouse4a4cd632005-06-22 14:56:47 +01001366 if (!audit_enabled && msg_type != AUDIT_USER_AVC)
1367 return 0;
Paul Moore763dafc2020-04-20 16:24:34 -04001368 /* exit early if there isn't at least one character to print */
1369 if (data_len < 2)
1370 return -EINVAL;
David Woodhouse0f45aa12005-06-19 19:35:50 +01001371
Richard Guy Briggs86b2efb2016-06-24 16:35:46 -04001372 err = audit_filter(msg_type, AUDIT_FILTER_USER);
Richard Guy Briggs724e4fcc2013-11-25 21:57:51 -05001373 if (err == 1) { /* match or error */
Paul Moore75612522020-02-24 16:38:57 -05001374 char *str = data;
1375
David Woodhouse4a4cd632005-06-22 14:56:47 +01001376 err = 0;
Miloslav Trmac522ed772007-07-15 23:40:56 -07001377 if (msg_type == AUDIT_USER_TTY) {
Peter Hurley37282a72016-01-09 22:55:31 -08001378 err = tty_audit_push();
Miloslav Trmac522ed772007-07-15 23:40:56 -07001379 if (err)
1380 break;
1381 }
Richard Guy Briggs626abcd2019-01-18 17:42:48 -05001382 audit_log_user_recv_msg(&ab, msg_type);
Paul Moore75612522020-02-24 16:38:57 -05001383 if (msg_type != AUDIT_USER_TTY) {
1384 /* ensure NULL termination */
1385 str[data_len - 1] = '\0';
Richard Guy Briggsb50eba72013-09-16 18:20:42 -04001386 audit_log_format(ab, " msg='%.*s'",
1387 AUDIT_MESSAGE_TEXT_MAX,
Paul Moore75612522020-02-24 16:38:57 -05001388 str);
1389 } else {
Eric Parisf7616102013-04-11 11:25:00 -04001390 audit_log_format(ab, " data=");
Shreenidhi Shedi5ee6cfd2022-05-15 13:01:09 +05301391 if (str[data_len - 1] == '\0')
Paul Moore75612522020-02-24 16:38:57 -05001392 data_len--;
1393 audit_log_n_untrustedstring(ab, str, data_len);
David Woodhouse4a4cd632005-06-22 14:56:47 +01001394 }
Eric Paris50397bd2008-01-07 18:14:19 -05001395 audit_log_end(ab);
David Woodhouse0f45aa12005-06-19 19:35:50 +01001396 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001397 break;
Amy Griffis93315ed2006-02-07 12:05:27 -05001398 case AUDIT_ADD_RULE:
1399 case AUDIT_DEL_RULE:
Paul Moore75612522020-02-24 16:38:57 -05001400 if (data_len < sizeof(struct audit_rule_data))
Amy Griffis93315ed2006-02-07 12:05:27 -05001401 return -EINVAL;
Eric Paris1a6b9f22008-01-07 17:09:31 -05001402 if (audit_enabled == AUDIT_LOCKED) {
Richard Guy Briggs626abcd2019-01-18 17:42:48 -05001403 audit_log_common_recv_msg(audit_context(), &ab,
1404 AUDIT_CONFIG_CHANGE);
Richard Guy Briggs53fc7a02018-12-10 17:17:48 -05001405 audit_log_format(ab, " op=%s audit_enabled=%d res=0",
1406 msg_type == AUDIT_ADD_RULE ?
1407 "add_rule" : "remove_rule",
1408 audit_enabled);
Eric Paris50397bd2008-01-07 18:14:19 -05001409 audit_log_end(ab);
Steve Grubb6a01b07f2007-01-19 14:39:55 -05001410 return -EPERM;
1411 }
Paul Moore75612522020-02-24 16:38:57 -05001412 err = audit_rule_change(msg_type, seq, data, data_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413 break;
Richard Guy Briggsce0d9f02013-11-20 14:01:53 -05001414 case AUDIT_LIST_RULES:
Eric W. Biederman6f285b12014-02-28 19:44:55 -08001415 err = audit_list_rules_send(skb, seq);
Richard Guy Briggsce0d9f02013-11-20 14:01:53 -05001416 break;
Al Viro74c3cbe2007-07-22 08:04:18 -04001417 case AUDIT_TRIM:
1418 audit_trim_trees();
Richard Guy Briggs626abcd2019-01-18 17:42:48 -05001419 audit_log_common_recv_msg(audit_context(), &ab,
1420 AUDIT_CONFIG_CHANGE);
Al Viro74c3cbe2007-07-22 08:04:18 -04001421 audit_log_format(ab, " op=trim res=1");
1422 audit_log_end(ab);
1423 break;
1424 case AUDIT_MAKE_EQUIV: {
1425 void *bufp = data;
1426 u32 sizes[2];
Paul Moore75612522020-02-24 16:38:57 -05001427 size_t msglen = data_len;
Al Viro74c3cbe2007-07-22 08:04:18 -04001428 char *old, *new;
1429
1430 err = -EINVAL;
Harvey Harrison7719e432008-04-27 02:39:56 -07001431 if (msglen < 2 * sizeof(u32))
Al Viro74c3cbe2007-07-22 08:04:18 -04001432 break;
1433 memcpy(sizes, bufp, 2 * sizeof(u32));
1434 bufp += 2 * sizeof(u32);
Harvey Harrison7719e432008-04-27 02:39:56 -07001435 msglen -= 2 * sizeof(u32);
1436 old = audit_unpack_string(&bufp, &msglen, sizes[0]);
Al Viro74c3cbe2007-07-22 08:04:18 -04001437 if (IS_ERR(old)) {
1438 err = PTR_ERR(old);
1439 break;
1440 }
Harvey Harrison7719e432008-04-27 02:39:56 -07001441 new = audit_unpack_string(&bufp, &msglen, sizes[1]);
Al Viro74c3cbe2007-07-22 08:04:18 -04001442 if (IS_ERR(new)) {
1443 err = PTR_ERR(new);
1444 kfree(old);
1445 break;
1446 }
1447 /* OK, here comes... */
1448 err = audit_tag_tree(old, new);
1449
Richard Guy Briggs626abcd2019-01-18 17:42:48 -05001450 audit_log_common_recv_msg(audit_context(), &ab,
1451 AUDIT_CONFIG_CHANGE);
Al Viro74c3cbe2007-07-22 08:04:18 -04001452 audit_log_format(ab, " op=make_equiv old=");
1453 audit_log_untrustedstring(ab, old);
1454 audit_log_format(ab, " new=");
1455 audit_log_untrustedstring(ab, new);
1456 audit_log_format(ab, " res=%d", !err);
1457 audit_log_end(ab);
1458 kfree(old);
1459 kfree(new);
1460 break;
1461 }
Steve Grubbc2f0c7c2005-05-06 12:38:39 +01001462 case AUDIT_SIGNAL_INFO:
Eric Paris939cbf22009-09-23 13:46:00 -04001463 len = 0;
1464 if (audit_sig_sid) {
1465 err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
1466 if (err)
1467 return err;
1468 }
Xiu Jianfengbc6e60a2021-12-14 19:48:54 +08001469 sig_data = kmalloc(struct_size(sig_data, ctx, len), GFP_KERNEL);
Al Viroe1396062006-05-25 10:19:47 -04001470 if (!sig_data) {
Eric Paris939cbf22009-09-23 13:46:00 -04001471 if (audit_sig_sid)
1472 security_release_secctx(ctx, len);
Al Viroe1396062006-05-25 10:19:47 -04001473 return -ENOMEM;
1474 }
Eric W. Biedermancca080d2012-02-07 16:53:48 -08001475 sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
Al Viroe1396062006-05-25 10:19:47 -04001476 sig_data->pid = audit_sig_pid;
Eric Paris939cbf22009-09-23 13:46:00 -04001477 if (audit_sig_sid) {
1478 memcpy(sig_data->ctx, ctx, len);
1479 security_release_secctx(ctx, len);
1480 }
Eric W. Biederman6f285b12014-02-28 19:44:55 -08001481 audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
Xiu Jianfeng30561b52021-12-17 09:01:51 +08001482 sig_data, struct_size(sig_data, ctx, len));
Al Viroe1396062006-05-25 10:19:47 -04001483 kfree(sig_data);
Steve Grubbc2f0c7c2005-05-06 12:38:39 +01001484 break;
Miloslav Trmac522ed772007-07-15 23:40:56 -07001485 case AUDIT_TTY_GET: {
1486 struct audit_tty_status s;
Peter Hurley2e28d382016-01-09 22:55:33 -08001487 unsigned int t;
Miloslav Trmac522ed772007-07-15 23:40:56 -07001488
Peter Hurley2e28d382016-01-09 22:55:33 -08001489 t = READ_ONCE(current->signal->audit_tty);
1490 s.enabled = t & AUDIT_TTY_ENABLE;
1491 s.log_passwd = !!(t & AUDIT_TTY_LOG_PASSWD);
Thomas Gleixner20703202009-12-09 14:19:35 +00001492
Eric W. Biederman6f285b12014-02-28 19:44:55 -08001493 audit_send_reply(skb, seq, AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
Miloslav Trmac522ed772007-07-15 23:40:56 -07001494 break;
1495 }
1496 case AUDIT_TTY_SET: {
Richard Guy Briggsa06e56b2013-11-15 11:29:02 -05001497 struct audit_tty_status s, old;
Richard Guy Briggsa06e56b2013-11-15 11:29:02 -05001498 struct audit_buffer *ab;
Peter Hurley2e28d382016-01-09 22:55:33 -08001499 unsigned int t;
Miloslav Trmac522ed772007-07-15 23:40:56 -07001500
Richard Guy Briggs46e959e2013-05-03 14:03:50 -04001501 memset(&s, 0, sizeof(s));
1502 /* guard against past and future API changes */
Paul Moore75612522020-02-24 16:38:57 -05001503 memcpy(&s, data, min_t(size_t, sizeof(s), data_len));
Eric Paris0e23bac2014-01-13 21:12:34 -05001504 /* check if new data is valid */
1505 if ((s.enabled != 0 && s.enabled != 1) ||
1506 (s.log_passwd != 0 && s.log_passwd != 1))
1507 err = -EINVAL;
1508
Peter Hurley2e28d382016-01-09 22:55:33 -08001509 if (err)
1510 t = READ_ONCE(current->signal->audit_tty);
1511 else {
1512 t = s.enabled | (-s.log_passwd & AUDIT_TTY_LOG_PASSWD);
1513 t = xchg(&current->signal->audit_tty, t);
Eric Paris0e23bac2014-01-13 21:12:34 -05001514 }
Peter Hurley2e28d382016-01-09 22:55:33 -08001515 old.enabled = t & AUDIT_TTY_ENABLE;
1516 old.log_passwd = !!(t & AUDIT_TTY_LOG_PASSWD);
Eric Paris0e23bac2014-01-13 21:12:34 -05001517
Richard Guy Briggs626abcd2019-01-18 17:42:48 -05001518 audit_log_common_recv_msg(audit_context(), &ab,
1519 AUDIT_CONFIG_CHANGE);
Eric Paris1ce319f2014-01-13 21:16:59 -05001520 audit_log_format(ab, " op=tty_set old-enabled=%d new-enabled=%d"
1521 " old-log_passwd=%d new-log_passwd=%d res=%d",
1522 old.enabled, s.enabled, old.log_passwd,
1523 s.log_passwd, !err);
Richard Guy Briggsa06e56b2013-11-15 11:29:02 -05001524 audit_log_end(ab);
Miloslav Trmac522ed772007-07-15 23:40:56 -07001525 break;
1526 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001527 default:
1528 err = -EINVAL;
1529 break;
1530 }
1531
1532 return err < 0 ? err : 0;
1533}
1534
Paul Moorea9d16202017-05-02 10:16:05 -04001535/**
1536 * audit_receive - receive messages from a netlink control socket
1537 * @skb: the message buffer
1538 *
1539 * Parse the provided skb and deal with any messages that may be present,
1540 * malformed skbs are discarded.
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001541 */
Paul Moorea9d16202017-05-02 10:16:05 -04001542static void audit_receive(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001543{
Eric Parisea7ae602009-06-11 14:31:35 -04001544 struct nlmsghdr *nlh;
1545 /*
Hong zhi guo94191212013-03-27 06:49:06 +00001546 * len MUST be signed for nlmsg_next to be able to dec it below 0
Eric Parisea7ae602009-06-11 14:31:35 -04001547 * if the nlmsg_len was not aligned
1548 */
1549 int len;
1550 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551
Eric Parisea7ae602009-06-11 14:31:35 -04001552 nlh = nlmsg_hdr(skb);
1553 len = skb->len;
1554
Paul Moorece4236312018-02-20 09:52:38 -05001555 audit_ctl_lock();
Hong zhi guo94191212013-03-27 06:49:06 +00001556 while (nlmsg_ok(nlh, len)) {
Eric Parisea7ae602009-06-11 14:31:35 -04001557 err = audit_receive_msg(skb, nlh);
1558 /* if err or if this message says it wants a response */
1559 if (err || (nlh->nlmsg_flags & NLM_F_ACK))
Johannes Berg2d4bc932017-04-12 14:34:04 +02001560 netlink_ack(skb, nlh, err, NULL);
Eric Parisea7ae602009-06-11 14:31:35 -04001561
Alexandru Copot2851da52013-03-28 23:31:29 +02001562 nlh = nlmsg_next(nlh, &len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001563 }
Paul Moorece4236312018-02-20 09:52:38 -05001564 audit_ctl_unlock();
Paul Moore8f110f52021-12-13 15:45:20 -05001565
1566 /* can't block with the ctrl lock, so penalize the sender now */
1567 if (audit_backlog_limit &&
1568 (skb_queue_len(&audit_queue) > audit_backlog_limit)) {
1569 DECLARE_WAITQUEUE(wait, current);
1570
1571 /* wake kauditd to try and flush the queue */
1572 wake_up_interruptible(&kauditd_wait);
1573
1574 add_wait_queue_exclusive(&audit_backlog_wait, &wait);
1575 set_current_state(TASK_UNINTERRUPTIBLE);
1576 schedule_timeout(audit_backlog_wait_time);
1577 remove_wait_queue(&audit_backlog_wait, &wait);
1578 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001579}
1580
Richard Guy Briggs9d2161b2020-04-22 17:37:04 -04001581/* Log information about who is connecting to the audit multicast socket */
1582static void audit_log_multicast(int group, const char *op, int err)
Richard Guy Briggs3a101b82014-04-22 21:31:56 -04001583{
Richard Guy Briggs9d2161b2020-04-22 17:37:04 -04001584 const struct cred *cred;
1585 struct tty_struct *tty;
1586 char comm[sizeof(current->comm)];
1587 struct audit_buffer *ab;
Richard Guy Briggs3a101b82014-04-22 21:31:56 -04001588
Richard Guy Briggs9d2161b2020-04-22 17:37:04 -04001589 if (!audit_enabled)
1590 return;
1591
1592 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_EVENT_LISTENER);
1593 if (!ab)
1594 return;
1595
1596 cred = current_cred();
1597 tty = audit_get_tty();
1598 audit_log_format(ab, "pid=%u uid=%u auid=%u tty=%s ses=%u",
1599 task_pid_nr(current),
1600 from_kuid(&init_user_ns, cred->uid),
1601 from_kuid(&init_user_ns, audit_get_loginuid(current)),
1602 tty ? tty_name(tty) : "(none)",
1603 audit_get_sessionid(current));
1604 audit_put_tty(tty);
1605 audit_log_task_context(ab); /* subj= */
1606 audit_log_format(ab, " comm=");
1607 audit_log_untrustedstring(ab, get_task_comm(comm, current));
1608 audit_log_d_path_exe(ab, current->mm); /* exe= */
1609 audit_log_format(ab, " nl-mcgrp=%d op=%s res=%d", group, op, !err);
1610 audit_log_end(ab);
1611}
1612
1613/* Run custom bind function on netlink socket group connect or bind requests. */
1614static int audit_multicast_bind(struct net *net, int group)
1615{
1616 int err = 0;
1617
1618 if (!capable(CAP_AUDIT_READ))
1619 err = -EPERM;
1620 audit_log_multicast(group, "connect", err);
1621 return err;
1622}
1623
1624static void audit_multicast_unbind(struct net *net, int group)
1625{
1626 audit_log_multicast(group, "disconnect", 0);
Richard Guy Briggs3a101b82014-04-22 21:31:56 -04001627}
1628
Richard Guy Briggs33faba72013-07-16 13:18:45 -04001629static int __net_init audit_net_init(struct net *net)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001630{
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +00001631 struct netlink_kernel_cfg cfg = {
1632 .input = audit_receive,
Richard Guy Briggs9d2161b2020-04-22 17:37:04 -04001633 .bind = audit_multicast_bind,
1634 .unbind = audit_multicast_unbind,
Richard Guy Briggs451f9212014-04-22 21:31:57 -04001635 .flags = NL_CFG_F_NONROOT_RECV,
1636 .groups = AUDIT_NLGRP_MAX,
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +00001637 };
Amy Griffisf368c07d2006-04-07 16:55:56 -04001638
Richard Guy Briggs33faba72013-07-16 13:18:45 -04001639 struct audit_net *aunet = net_generic(net, audit_net_id);
1640
Paul Moore5b523302017-03-21 11:26:35 -04001641 aunet->sk = netlink_kernel_create(net, NETLINK_AUDIT, &cfg);
1642 if (aunet->sk == NULL) {
Richard Guy Briggs33faba72013-07-16 13:18:45 -04001643 audit_panic("cannot initialize netlink socket in namespace");
Gao feng11ee39e2013-12-17 11:10:41 +08001644 return -ENOMEM;
1645 }
Paul Mooref4b3ee32021-12-09 11:46:07 -05001646 /* limit the timeout in case auditd is blocked/stopped */
1647 aunet->sk->sk_sndtimeo = HZ / 10;
Paul Moore5b523302017-03-21 11:26:35 -04001648
Richard Guy Briggs33faba72013-07-16 13:18:45 -04001649 return 0;
1650}
1651
1652static void __net_exit audit_net_exit(struct net *net)
1653{
1654 struct audit_net *aunet = net_generic(net, audit_net_id);
Richard Guy Briggs33faba72013-07-16 13:18:45 -04001655
Paul Moore48d0e022017-05-02 10:16:05 -04001656 /* NOTE: you would think that we would want to check the auditd
1657 * connection and potentially reset it here if it lives in this
1658 * namespace, but since the auditd connection tracking struct holds a
1659 * reference to this namespace (see auditd_set()) we are only ever
1660 * going to get here after that connection has been released */
Paul Moore5b523302017-03-21 11:26:35 -04001661
1662 netlink_kernel_release(aunet->sk);
Richard Guy Briggs33faba72013-07-16 13:18:45 -04001663}
1664
Richard Guy Briggs86268772013-07-16 13:18:45 -04001665static struct pernet_operations audit_net_ops __net_initdata = {
Richard Guy Briggs33faba72013-07-16 13:18:45 -04001666 .init = audit_net_init,
1667 .exit = audit_net_exit,
1668 .id = &audit_net_id,
1669 .size = sizeof(struct audit_net),
1670};
1671
1672/* Initialize audit support at boot time. */
1673static int __init audit_init(void)
1674{
1675 int i;
1676
Eric Parisa3f07112008-11-05 12:47:09 -05001677 if (audit_initialized == AUDIT_DISABLED)
1678 return 0;
1679
Paul Moore8cc96382017-05-02 10:16:05 -04001680 audit_buffer_cache = kmem_cache_create("audit_buffer",
1681 sizeof(struct audit_buffer),
1682 0, SLAB_PANIC, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001683
Paul Mooreaf8b8242016-11-29 16:53:24 -05001684 skb_queue_head_init(&audit_queue);
Paul Moorec6480202016-11-29 16:53:25 -05001685 skb_queue_head_init(&audit_retry_queue);
Paul Mooreaf8b8242016-11-29 16:53:24 -05001686 skb_queue_head_init(&audit_hold_queue);
Darrel Goeddel3dc7e312006-03-10 18:14:06 -06001687
Amy Griffisf368c07d2006-04-07 16:55:56 -04001688 for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
1689 INIT_LIST_HEAD(&audit_inode_hash[i]);
Amy Griffisf368c07d2006-04-07 16:55:56 -04001690
Paul Moorece4236312018-02-20 09:52:38 -05001691 mutex_init(&audit_cmd_mutex.lock);
1692 audit_cmd_mutex.owner = NULL;
1693
Paul Moore5b523302017-03-21 11:26:35 -04001694 pr_info("initializing netlink subsys (%s)\n",
1695 audit_default ? "enabled" : "disabled");
1696 register_pernet_subsys(&audit_net_ops);
1697
1698 audit_initialized = AUDIT_INITIALIZED;
Paul Moore5b523302017-03-21 11:26:35 -04001699
Paul Moore6c925562016-11-29 16:53:23 -05001700 kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
1701 if (IS_ERR(kauditd_task)) {
1702 int err = PTR_ERR(kauditd_task);
1703 panic("audit: failed to start the kauditd thread (%d)\n", err);
1704 }
1705
Steve Grubb7c397d02016-12-14 15:59:46 -05001706 audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL,
1707 "state=initialized audit_enabled=%u res=1",
1708 audit_enabled);
Paul Moore6c925562016-11-29 16:53:23 -05001709
Linus Torvalds1da177e2005-04-16 15:20:36 -07001710 return 0;
1711}
Paul Moorebe4104a2017-09-01 09:44:44 -04001712postcore_initcall(audit_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001713
Greg Edwards11dd2662018-03-05 15:05:20 -07001714/*
1715 * Process kernel command-line parameter at boot time.
1716 * audit={0|off} or audit={1|on}.
1717 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001718static int __init audit_enable(char *str)
1719{
Greg Edwards11dd2662018-03-05 15:05:20 -07001720 if (!strcasecmp(str, "off") || !strcmp(str, "0"))
1721 audit_default = AUDIT_OFF;
1722 else if (!strcasecmp(str, "on") || !strcmp(str, "1"))
1723 audit_default = AUDIT_ON;
1724 else {
1725 pr_err("audit: invalid 'audit' parameter value (%s)\n", str);
1726 audit_default = AUDIT_ON;
1727 }
Paul Moore80ab4df2017-09-01 09:44:51 -04001728
1729 if (audit_default == AUDIT_OFF)
Eric Parisa3f07112008-11-05 12:47:09 -05001730 audit_initialized = AUDIT_DISABLED;
Paul Moore5d842a52017-09-01 09:45:05 -04001731 if (audit_set_enabled(audit_default))
Greg Edwards11dd2662018-03-05 15:05:20 -07001732 pr_err("audit: error setting audit state (%d)\n",
1733 audit_default);
Eric Parisa3f07112008-11-05 12:47:09 -05001734
Joe Perchesd957f7b2014-01-14 10:33:12 -08001735 pr_info("%s\n", audit_default ?
Gao fengd3ca0342013-10-31 14:31:01 +08001736 "enabled (after initialization)" : "disabled (until reboot)");
Eric Parisa3f07112008-11-05 12:47:09 -05001737
OGAWA Hirofumi9b410462006-03-31 02:30:33 -08001738 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001739}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001740__setup("audit=", audit_enable);
1741
Richard Guy Briggsf910fde2013-09-17 12:34:52 -04001742/* Process kernel command-line parameter at boot time.
1743 * audit_backlog_limit=<n> */
1744static int __init audit_backlog_limit_set(char *str)
1745{
Joe Perches3e1d0bb2014-01-14 10:33:13 -08001746 u32 audit_backlog_limit_arg;
Joe Perchesd957f7b2014-01-14 10:33:12 -08001747
Richard Guy Briggsf910fde2013-09-17 12:34:52 -04001748 pr_info("audit_backlog_limit: ");
Joe Perches3e1d0bb2014-01-14 10:33:13 -08001749 if (kstrtouint(str, 0, &audit_backlog_limit_arg)) {
1750 pr_cont("using default of %u, unable to parse %s\n",
Joe Perchesd957f7b2014-01-14 10:33:12 -08001751 audit_backlog_limit, str);
Richard Guy Briggsf910fde2013-09-17 12:34:52 -04001752 return 1;
1753 }
Joe Perches3e1d0bb2014-01-14 10:33:13 -08001754
1755 audit_backlog_limit = audit_backlog_limit_arg;
Joe Perchesd957f7b2014-01-14 10:33:12 -08001756 pr_cont("%d\n", audit_backlog_limit);
Richard Guy Briggsf910fde2013-09-17 12:34:52 -04001757
1758 return 1;
1759}
1760__setup("audit_backlog_limit=", audit_backlog_limit_set);
1761
Chris Wright16e19042005-05-06 15:53:34 +01001762static void audit_buffer_free(struct audit_buffer *ab)
1763{
Chris Wright8fc61152005-05-06 15:54:17 +01001764 if (!ab)
1765 return;
1766
Markus Elfringd865e572016-01-13 09:18:55 -05001767 kfree_skb(ab->skb);
Paul Moore8cc96382017-05-02 10:16:05 -04001768 kmem_cache_free(audit_buffer_cache, ab);
Chris Wright16e19042005-05-06 15:53:34 +01001769}
1770
Paul Moore8cc96382017-05-02 10:16:05 -04001771static struct audit_buffer *audit_buffer_alloc(struct audit_context *ctx,
1772 gfp_t gfp_mask, int type)
Chris Wright16e19042005-05-06 15:53:34 +01001773{
Paul Moore8cc96382017-05-02 10:16:05 -04001774 struct audit_buffer *ab;
Chris Wright16e19042005-05-06 15:53:34 +01001775
Paul Moore8cc96382017-05-02 10:16:05 -04001776 ab = kmem_cache_alloc(audit_buffer_cache, gfp_mask);
1777 if (!ab)
1778 return NULL;
Eric Parisee080e62009-06-11 14:31:35 -04001779
1780 ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask);
1781 if (!ab->skb)
David S. Millerc64e66c2012-06-26 21:45:21 -07001782 goto err;
Paul Moore8cc96382017-05-02 10:16:05 -04001783 if (!nlmsg_put(ab->skb, 0, 0, type, 0, 0))
1784 goto err;
Eric Parisee080e62009-06-11 14:31:35 -04001785
Paul Moore8cc96382017-05-02 10:16:05 -04001786 ab->ctx = ctx;
1787 ab->gfp_mask = gfp_mask;
Eric Parisee080e62009-06-11 14:31:35 -04001788
Chris Wright16e19042005-05-06 15:53:34 +01001789 return ab;
Eric Parisee080e62009-06-11 14:31:35 -04001790
Chris Wright8fc61152005-05-06 15:54:17 +01001791err:
1792 audit_buffer_free(ab);
1793 return NULL;
Chris Wright16e19042005-05-06 15:53:34 +01001794}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001795
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001796/**
1797 * audit_serial - compute a serial number for the audit record
1798 *
1799 * Compute a serial number for the audit record. Audit records are
David Woodhousebfb44962005-05-21 21:08:09 +01001800 * written to user-space as soon as they are generated, so a complete
1801 * audit record may be written in several pieces. The timestamp of the
1802 * record and this serial number are used by the user-space tools to
1803 * determine which pieces belong to the same audit record. The
1804 * (timestamp,serial) tuple is unique for each syscall and is live from
1805 * syscall entry to syscall exit.
1806 *
David Woodhousebfb44962005-05-21 21:08:09 +01001807 * NOTE: Another possibility is to store the formatted records off the
1808 * audit context (for those records that have a context), and emit them
1809 * all at syscall exit. However, this could delay the reporting of
1810 * significant errors until syscall exit (or never, if the system
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001811 * halts).
1812 */
David Woodhousebfb44962005-05-21 21:08:09 +01001813unsigned int audit_serial(void)
1814{
Richard Guy Briggs01478d72014-06-13 18:22:00 -04001815 static atomic_t serial = ATOMIC_INIT(0);
David Woodhousebfb44962005-05-21 21:08:09 +01001816
Yejune Deng6b321182020-11-30 16:35:45 +08001817 return atomic_inc_return(&serial);
David Woodhousebfb44962005-05-21 21:08:09 +01001818}
1819
Daniel Walker5600b892007-10-18 03:06:10 -07001820static inline void audit_get_stamp(struct audit_context *ctx,
Deepa Dinamani2115bb22017-05-02 10:16:05 -04001821 struct timespec64 *t, unsigned int *serial)
David Woodhousebfb44962005-05-21 21:08:09 +01001822{
Al Viro48887e62008-12-06 01:05:50 -05001823 if (!ctx || !auditsc_get_stamp(ctx, t, serial)) {
Paul Moore290e44b72018-07-17 14:45:08 -04001824 ktime_get_coarse_real_ts64(t);
David Woodhousebfb44962005-05-21 21:08:09 +01001825 *serial = audit_serial();
1826 }
1827}
1828
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001829/**
1830 * audit_log_start - obtain an audit buffer
1831 * @ctx: audit_context (may be NULL)
1832 * @gfp_mask: type of allocation
1833 * @type: audit message type
1834 *
1835 * Returns audit_buffer pointer on success or NULL on error.
1836 *
1837 * Obtain an audit buffer. This routine does locking to obtain the
1838 * audit buffer, but then no locking is required for calls to
1839 * audit_log_*format. If the task (ctx) is a task that is currently in a
1840 * syscall, then the syscall is marked as auditable and an audit record
1841 * will be written at syscall exit. If there is no associated task, then
1842 * task context (ctx) should be NULL.
1843 */
Al Viro9796fdd2005-10-21 03:22:03 -04001844struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001845 int type)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001846{
Paul Moore31975422016-11-29 16:53:25 -05001847 struct audit_buffer *ab;
Deepa Dinamani2115bb22017-05-02 10:16:05 -04001848 struct timespec64 t;
Kees Cook3f649ab2020-06-03 13:09:38 -07001849 unsigned int serial;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001850
Eric Parisa3f07112008-11-05 12:47:09 -05001851 if (audit_initialized != AUDIT_INITIALIZED)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001852 return NULL;
1853
Richard Guy Briggsd904ac02018-06-05 11:45:07 -04001854 if (unlikely(!audit_filter(type, AUDIT_FILTER_EXCLUDE)))
Dustin Kirklandc8edc802005-11-03 16:12:36 +00001855 return NULL;
1856
Paul Moore5b523302017-03-21 11:26:35 -04001857 /* NOTE: don't ever fail/sleep on these two conditions:
Paul Moorea09cfa42016-11-29 16:53:26 -05001858 * 1. auditd generated record - since we need auditd to drain the
1859 * queue; also, when we are checking for auditd, compare PIDs using
1860 * task_tgid_vnr() since auditd_pid is set in audit_receive_msg()
1861 * using a PID anchored in the caller's namespace
Paul Moore5b523302017-03-21 11:26:35 -04001862 * 2. generator holding the audit_cmd_mutex - we don't want to block
Paul Moore8f110f52021-12-13 15:45:20 -05001863 * while holding the mutex, although we do penalize the sender
1864 * later in audit_receive() when it is safe to block
1865 */
Paul Moorece4236312018-02-20 09:52:38 -05001866 if (!(auditd_test_task(current) || audit_ctl_owner_current())) {
Paul Moore5b523302017-03-21 11:26:35 -04001867 long stime = audit_backlog_wait_time;
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001868
Paul Moore31975422016-11-29 16:53:25 -05001869 while (audit_backlog_limit &&
1870 (skb_queue_len(&audit_queue) > audit_backlog_limit)) {
1871 /* wake kauditd to try and flush the queue */
1872 wake_up_interruptible(&kauditd_wait);
David Woodhouseac4cec42005-07-02 14:08:48 +01001873
Paul Moore31975422016-11-29 16:53:25 -05001874 /* sleep if we are allowed and we haven't exhausted our
1875 * backlog wait limit */
Paul Moore5b523302017-03-21 11:26:35 -04001876 if (gfpflags_allow_blocking(gfp_mask) && (stime > 0)) {
Max Englanderb43870c2020-07-04 15:15:28 +00001877 long rtime = stime;
1878
Paul Moore31975422016-11-29 16:53:25 -05001879 DECLARE_WAITQUEUE(wait, current);
1880
1881 add_wait_queue_exclusive(&audit_backlog_wait,
1882 &wait);
1883 set_current_state(TASK_UNINTERRUPTIBLE);
Max Englanderb43870c2020-07-04 15:15:28 +00001884 stime = schedule_timeout(rtime);
1885 atomic_add(rtime - stime, &audit_backlog_wait_time_actual);
Paul Moore31975422016-11-29 16:53:25 -05001886 remove_wait_queue(&audit_backlog_wait, &wait);
1887 } else {
1888 if (audit_rate_check() && printk_ratelimit())
1889 pr_warn("audit_backlog=%d > audit_backlog_limit=%d\n",
1890 skb_queue_len(&audit_queue),
1891 audit_backlog_limit);
1892 audit_log_lost("backlog limit exceeded");
1893 return NULL;
Konstantin Khlebnikov8ac1c8d2013-09-24 15:27:42 -07001894 }
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001895 }
David Woodhousefb19b4c2005-05-19 14:55:56 +01001896 }
1897
David Woodhouse9ad9ad32005-06-22 15:04:33 +01001898 ab = audit_buffer_alloc(ctx, gfp_mask, type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001899 if (!ab) {
1900 audit_log_lost("out of memory in audit_log_start");
1901 return NULL;
1902 }
1903
David Woodhousebfb44962005-05-21 21:08:09 +01001904 audit_get_stamp(ab->ctx, &t, &serial);
Richard Guy Briggs6d915472020-09-22 08:44:50 -04001905 /* cancel dummy context to enable supporting records */
1906 if (ctx)
1907 ctx->dummy = 0;
Deepa Dinamani2115bb22017-05-02 10:16:05 -04001908 audit_log_format(ab, "audit(%llu.%03lu:%u): ",
1909 (unsigned long long)t.tv_sec, t.tv_nsec/1000000, serial);
Paul Moore31975422016-11-29 16:53:25 -05001910
Linus Torvalds1da177e2005-04-16 15:20:36 -07001911 return ab;
1912}
1913
Chris Wright8fc61152005-05-06 15:54:17 +01001914/**
Chris Wright5ac52f32005-05-06 15:54:53 +01001915 * audit_expand - expand skb in the audit buffer
Chris Wright8fc61152005-05-06 15:54:17 +01001916 * @ab: audit_buffer
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001917 * @extra: space to add at tail of the skb
Chris Wright8fc61152005-05-06 15:54:17 +01001918 *
1919 * Returns 0 (no space) on failed expansion, or available space if
1920 * successful.
1921 */
David Woodhousee3b926b2005-05-10 18:56:08 +01001922static inline int audit_expand(struct audit_buffer *ab, int extra)
Chris Wright8fc61152005-05-06 15:54:17 +01001923{
Chris Wright5ac52f32005-05-06 15:54:53 +01001924 struct sk_buff *skb = ab->skb;
Herbert Xu406a1d82008-01-28 20:47:09 -08001925 int oldtail = skb_tailroom(skb);
1926 int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask);
1927 int newtail = skb_tailroom(skb);
1928
Chris Wright5ac52f32005-05-06 15:54:53 +01001929 if (ret < 0) {
1930 audit_log_lost("out of memory in audit_expand");
Chris Wright8fc61152005-05-06 15:54:17 +01001931 return 0;
Chris Wright5ac52f32005-05-06 15:54:53 +01001932 }
Herbert Xu406a1d82008-01-28 20:47:09 -08001933
1934 skb->truesize += newtail - oldtail;
1935 return newtail;
Chris Wright8fc61152005-05-06 15:54:17 +01001936}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001937
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001938/*
1939 * Format an audit message into the audit buffer. If there isn't enough
Linus Torvalds1da177e2005-04-16 15:20:36 -07001940 * room in the audit buffer, more room will be allocated and vsnprint
1941 * will be called a second time. Currently, we assume that a printk
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001942 * can't format message larger than 1024 bytes, so we don't either.
1943 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001944static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
1945 va_list args)
1946{
1947 int len, avail;
Chris Wright5ac52f32005-05-06 15:54:53 +01001948 struct sk_buff *skb;
David Woodhouseeecb0a72005-05-10 18:58:51 +01001949 va_list args2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001950
1951 if (!ab)
1952 return;
1953
Chris Wright5ac52f32005-05-06 15:54:53 +01001954 BUG_ON(!ab->skb);
1955 skb = ab->skb;
1956 avail = skb_tailroom(skb);
1957 if (avail == 0) {
David Woodhousee3b926b2005-05-10 18:56:08 +01001958 avail = audit_expand(ab, AUDIT_BUFSIZ);
Chris Wright8fc61152005-05-06 15:54:17 +01001959 if (!avail)
1960 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001961 }
David Woodhouseeecb0a72005-05-10 18:58:51 +01001962 va_copy(args2, args);
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001963 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001964 if (len >= avail) {
1965 /* The printk buffer is 1024 bytes long, so if we get
1966 * here and AUDIT_BUFSIZ is at least 1024, then we can
1967 * log everything that printk could have logged. */
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001968 avail = audit_expand(ab,
1969 max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
Chris Wright8fc61152005-05-06 15:54:17 +01001970 if (!avail)
Jesper Juhla0e86bd2012-01-08 22:44:29 +01001971 goto out_va_end;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07001972 len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001973 }
Steve Grubb168b7172005-05-19 10:24:22 +01001974 if (len > 0)
1975 skb_put(skb, len);
Jesper Juhla0e86bd2012-01-08 22:44:29 +01001976out_va_end:
1977 va_end(args2);
Chris Wright8fc61152005-05-06 15:54:17 +01001978out:
1979 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001980}
1981
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07001982/**
1983 * audit_log_format - format a message into the audit buffer.
1984 * @ab: audit_buffer
1985 * @fmt: format string
1986 * @...: optional parameters matching @fmt string
1987 *
1988 * All the work is done in audit_log_vformat.
1989 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001990void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
1991{
1992 va_list args;
1993
1994 if (!ab)
1995 return;
1996 va_start(args, fmt);
1997 audit_log_vformat(ab, fmt, args);
1998 va_end(args);
1999}
2000
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002001/**
Geliang Tang196a5082017-08-07 21:44:24 +08002002 * audit_log_n_hex - convert a buffer to hex and append it to the audit skb
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002003 * @ab: the audit_buffer
2004 * @buf: buffer to convert to hex
2005 * @len: length of @buf to be converted
2006 *
2007 * No return value; failure to expand is silently ignored.
2008 *
2009 * This function will take the passed buf and convert it into a string of
2010 * ascii hex digits. The new string is placed onto the skb.
2011 */
Eric Parisb556f8a2008-04-18 10:12:59 -04002012void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
Steve Grubb168b7172005-05-19 10:24:22 +01002013 size_t len)
83c7d092005-04-29 15:54:44 +01002014{
Steve Grubb168b7172005-05-19 10:24:22 +01002015 int i, avail, new_len;
2016 unsigned char *ptr;
2017 struct sk_buff *skb;
83c7d092005-04-29 15:54:44 +01002018
Amy Griffis8ef2d302006-09-07 17:03:02 -04002019 if (!ab)
2020 return;
2021
Steve Grubb168b7172005-05-19 10:24:22 +01002022 BUG_ON(!ab->skb);
2023 skb = ab->skb;
2024 avail = skb_tailroom(skb);
2025 new_len = len<<1;
2026 if (new_len >= avail) {
2027 /* Round the buffer request up to the next multiple */
2028 new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1);
2029 avail = audit_expand(ab, new_len);
2030 if (!avail)
2031 return;
2032 }
2033
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07002034 ptr = skb_tail_pointer(skb);
Joe Perchesb8dbc322014-01-13 23:31:27 -08002035 for (i = 0; i < len; i++)
2036 ptr = hex_byte_pack_upper(ptr, buf[i]);
Steve Grubb168b7172005-05-19 10:24:22 +01002037 *ptr = 0;
2038 skb_put(skb, len << 1); /* new string is twice the old string */
83c7d092005-04-29 15:54:44 +01002039}
2040
Amy Griffis9c937dc2006-06-08 23:19:31 -04002041/*
2042 * Format a string of no more than slen characters into the audit buffer,
2043 * enclosed in quote marks.
2044 */
Eric Parisb556f8a2008-04-18 10:12:59 -04002045void audit_log_n_string(struct audit_buffer *ab, const char *string,
2046 size_t slen)
Amy Griffis9c937dc2006-06-08 23:19:31 -04002047{
2048 int avail, new_len;
2049 unsigned char *ptr;
2050 struct sk_buff *skb;
2051
Amy Griffis8ef2d302006-09-07 17:03:02 -04002052 if (!ab)
2053 return;
2054
Amy Griffis9c937dc2006-06-08 23:19:31 -04002055 BUG_ON(!ab->skb);
2056 skb = ab->skb;
2057 avail = skb_tailroom(skb);
2058 new_len = slen + 3; /* enclosing quotes + null terminator */
2059 if (new_len > avail) {
2060 avail = audit_expand(ab, new_len);
2061 if (!avail)
2062 return;
2063 }
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -07002064 ptr = skb_tail_pointer(skb);
Amy Griffis9c937dc2006-06-08 23:19:31 -04002065 *ptr++ = '"';
2066 memcpy(ptr, string, slen);
2067 ptr += slen;
2068 *ptr++ = '"';
2069 *ptr = 0;
2070 skb_put(skb, slen + 2); /* don't include null terminator */
2071}
2072
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002073/**
Eric Parisde6bbd12008-01-07 14:31:58 -05002074 * audit_string_contains_control - does a string need to be logged in hex
Dave Jonesf706d5d2008-03-28 14:15:56 -07002075 * @string: string to be checked
2076 * @len: max length of the string to check
Eric Parisde6bbd12008-01-07 14:31:58 -05002077 */
Yaowei Bai9fcf8362015-11-04 08:23:51 -05002078bool audit_string_contains_control(const char *string, size_t len)
Eric Parisde6bbd12008-01-07 14:31:58 -05002079{
2080 const unsigned char *p;
Miloslav Trmacb3897f52009-03-19 09:48:27 -04002081 for (p = string; p < (const unsigned char *)string + len; p++) {
Vesa-Matti J Kari1d6c9642008-07-23 00:06:13 +03002082 if (*p == '"' || *p < 0x21 || *p > 0x7e)
Yaowei Bai9fcf8362015-11-04 08:23:51 -05002083 return true;
Eric Parisde6bbd12008-01-07 14:31:58 -05002084 }
Yaowei Bai9fcf8362015-11-04 08:23:51 -05002085 return false;
Eric Parisde6bbd12008-01-07 14:31:58 -05002086}
2087
2088/**
Miloslav Trmac522ed772007-07-15 23:40:56 -07002089 * audit_log_n_untrustedstring - log a string that may contain random characters
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002090 * @ab: audit_buffer
Dave Jonesf706d5d2008-03-28 14:15:56 -07002091 * @len: length of string (not including trailing null)
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002092 * @string: string to be logged
2093 *
2094 * This code will escape a string that is passed to it if the string
2095 * contains a control character, unprintable character, double quote mark,
Steve Grubb168b7172005-05-19 10:24:22 +01002096 * or a space. Unescaped strings will start and end with a double quote mark.
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002097 * Strings that are escaped are printed in hex (2 digits per char).
Amy Griffis9c937dc2006-06-08 23:19:31 -04002098 *
2099 * The caller specifies the number of characters in the string to log, which may
2100 * or may not be the entire string.
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002101 */
Eric Parisb556f8a2008-04-18 10:12:59 -04002102void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string,
2103 size_t len)
83c7d092005-04-29 15:54:44 +01002104{
Eric Parisde6bbd12008-01-07 14:31:58 -05002105 if (audit_string_contains_control(string, len))
Eric Parisb556f8a2008-04-18 10:12:59 -04002106 audit_log_n_hex(ab, string, len);
Eric Parisde6bbd12008-01-07 14:31:58 -05002107 else
Eric Parisb556f8a2008-04-18 10:12:59 -04002108 audit_log_n_string(ab, string, len);
83c7d092005-04-29 15:54:44 +01002109}
2110
Amy Griffis9c937dc2006-06-08 23:19:31 -04002111/**
Miloslav Trmac522ed772007-07-15 23:40:56 -07002112 * audit_log_untrustedstring - log a string that may contain random characters
Amy Griffis9c937dc2006-06-08 23:19:31 -04002113 * @ab: audit_buffer
2114 * @string: string to be logged
2115 *
Miloslav Trmac522ed772007-07-15 23:40:56 -07002116 * Same as audit_log_n_untrustedstring(), except that strlen is used to
Amy Griffis9c937dc2006-06-08 23:19:31 -04002117 * determine string length.
2118 */
Eric Parisde6bbd12008-01-07 14:31:58 -05002119void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
Amy Griffis9c937dc2006-06-08 23:19:31 -04002120{
Eric Parisb556f8a2008-04-18 10:12:59 -04002121 audit_log_n_untrustedstring(ab, string, strlen(string));
Amy Griffis9c937dc2006-06-08 23:19:31 -04002122}
2123
Steve Grubb168b7172005-05-19 10:24:22 +01002124/* This is a helper-function to print the escaped d_path */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002125void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
Al Viro66b3fad2012-03-14 21:48:20 -04002126 const struct path *path)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002127{
Jan Blunck44707fd2008-02-14 19:38:33 -08002128 char *p, *pathname;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002129
Chris Wright8fc61152005-05-06 15:54:17 +01002130 if (prefix)
Kees Cookc158a352012-01-06 14:07:10 -08002131 audit_log_format(ab, "%s", prefix);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002132
Steve Grubb168b7172005-05-19 10:24:22 +01002133 /* We will allow 11 spaces for ' (deleted)' to be appended */
Jan Blunck44707fd2008-02-14 19:38:33 -08002134 pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
2135 if (!pathname) {
Richard Guy Briggsf1d9b232020-07-13 15:51:59 -04002136 audit_log_format(ab, "\"<no_memory>\"");
Steve Grubb168b7172005-05-19 10:24:22 +01002137 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002138 }
Jan Blunckcf28b482008-02-14 19:38:44 -08002139 p = d_path(path, pathname, PATH_MAX+11);
Steve Grubb168b7172005-05-19 10:24:22 +01002140 if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
2141 /* FIXME: can we save some information here? */
Richard Guy Briggsf1d9b232020-07-13 15:51:59 -04002142 audit_log_format(ab, "\"<too_long>\"");
Daniel Walker5600b892007-10-18 03:06:10 -07002143 } else
Steve Grubb168b7172005-05-19 10:24:22 +01002144 audit_log_untrustedstring(ab, p);
Jan Blunck44707fd2008-02-14 19:38:33 -08002145 kfree(pathname);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146}
2147
Eric Paris4d3fb702013-04-30 09:53:34 -04002148void audit_log_session_info(struct audit_buffer *ab)
2149{
Eric Paris4440e852013-11-27 17:35:17 -05002150 unsigned int sessionid = audit_get_sessionid(current);
Eric Paris4d3fb702013-04-30 09:53:34 -04002151 uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current));
2152
Richard Guy Briggsa2c97da2018-11-16 16:30:10 -05002153 audit_log_format(ab, "auid=%u ses=%u", auid, sessionid);
Eric Paris4d3fb702013-04-30 09:53:34 -04002154}
2155
Eric Paris9d960982009-06-11 14:31:37 -04002156void audit_log_key(struct audit_buffer *ab, char *key)
2157{
2158 audit_log_format(ab, " key=");
2159 if (key)
2160 audit_log_untrustedstring(ab, key);
2161 else
2162 audit_log_format(ab, "(null)");
2163}
2164
Eric Parisb24a30a2013-04-30 15:30:32 -04002165int audit_log_task_context(struct audit_buffer *ab)
2166{
2167 char *ctx = NULL;
2168 unsigned len;
2169 int error;
2170 u32 sid;
2171
Paul Moore63269482021-09-29 11:01:21 -04002172 security_current_getsecid_subj(&sid);
Eric Parisb24a30a2013-04-30 15:30:32 -04002173 if (!sid)
2174 return 0;
2175
2176 error = security_secid_to_secctx(sid, &ctx, &len);
2177 if (error) {
2178 if (error != -EINVAL)
2179 goto error_path;
2180 return 0;
2181 }
2182
2183 audit_log_format(ab, " subj=%s", ctx);
2184 security_release_secctx(ctx, len);
2185 return 0;
2186
2187error_path:
2188 audit_panic("error in audit_log_task_context");
2189 return error;
2190}
2191EXPORT_SYMBOL(audit_log_task_context);
2192
Davidlohr Bueso4766b192015-02-22 18:20:00 -08002193void audit_log_d_path_exe(struct audit_buffer *ab,
2194 struct mm_struct *mm)
2195{
Davidlohr Bueso5b282552015-02-22 18:20:09 -08002196 struct file *exe_file;
Davidlohr Bueso4766b192015-02-22 18:20:00 -08002197
Davidlohr Bueso5b282552015-02-22 18:20:09 -08002198 if (!mm)
2199 goto out_null;
2200
2201 exe_file = get_mm_exe_file(mm);
2202 if (!exe_file)
2203 goto out_null;
2204
2205 audit_log_d_path(ab, " exe=", &exe_file->f_path);
2206 fput(exe_file);
2207 return;
2208out_null:
2209 audit_log_format(ab, " exe=(null)");
Davidlohr Bueso4766b192015-02-22 18:20:00 -08002210}
2211
Paul Moore2a1fe212018-11-26 18:40:07 -05002212struct tty_struct *audit_get_tty(void)
Richard Guy Briggs3f5be2d2016-06-28 12:07:50 -04002213{
2214 struct tty_struct *tty = NULL;
2215 unsigned long flags;
2216
Paul Moore2a1fe212018-11-26 18:40:07 -05002217 spin_lock_irqsave(&current->sighand->siglock, flags);
2218 if (current->signal)
2219 tty = tty_kref_get(current->signal->tty);
2220 spin_unlock_irqrestore(&current->sighand->siglock, flags);
Richard Guy Briggs3f5be2d2016-06-28 12:07:50 -04002221 return tty;
2222}
2223
2224void audit_put_tty(struct tty_struct *tty)
2225{
2226 tty_kref_put(tty);
2227}
2228
Paul Moore2a1fe212018-11-26 18:40:07 -05002229void audit_log_task_info(struct audit_buffer *ab)
Eric Parisb24a30a2013-04-30 15:30:32 -04002230{
2231 const struct cred *cred;
Paul Moore2a1fe212018-11-26 18:40:07 -05002232 char comm[sizeof(current->comm)];
Richard Guy Briggsdb0a6fb2016-04-21 14:14:01 -04002233 struct tty_struct *tty;
Eric Parisb24a30a2013-04-30 15:30:32 -04002234
2235 if (!ab)
2236 return;
2237
Eric Parisb24a30a2013-04-30 15:30:32 -04002238 cred = current_cred();
Paul Moore2a1fe212018-11-26 18:40:07 -05002239 tty = audit_get_tty();
Eric Parisb24a30a2013-04-30 15:30:32 -04002240 audit_log_format(ab,
Richard Guy Briggsc92cdeb2013-12-10 22:10:41 -05002241 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
Eric Parisb24a30a2013-04-30 15:30:32 -04002242 " euid=%u suid=%u fsuid=%u"
Richard Guy Briggs2f2ad102013-07-15 10:23:11 -04002243 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
Paul Moore2a1fe212018-11-26 18:40:07 -05002244 task_ppid_nr(current),
2245 task_tgid_nr(current),
2246 from_kuid(&init_user_ns, audit_get_loginuid(current)),
Eric Parisb24a30a2013-04-30 15:30:32 -04002247 from_kuid(&init_user_ns, cred->uid),
2248 from_kgid(&init_user_ns, cred->gid),
2249 from_kuid(&init_user_ns, cred->euid),
2250 from_kuid(&init_user_ns, cred->suid),
2251 from_kuid(&init_user_ns, cred->fsuid),
2252 from_kgid(&init_user_ns, cred->egid),
2253 from_kgid(&init_user_ns, cred->sgid),
2254 from_kgid(&init_user_ns, cred->fsgid),
Richard Guy Briggsdb0a6fb2016-04-21 14:14:01 -04002255 tty ? tty_name(tty) : "(none)",
Paul Moore2a1fe212018-11-26 18:40:07 -05002256 audit_get_sessionid(current));
Richard Guy Briggsdb0a6fb2016-04-21 14:14:01 -04002257 audit_put_tty(tty);
Eric Parisb24a30a2013-04-30 15:30:32 -04002258 audit_log_format(ab, " comm=");
Paul Moore2a1fe212018-11-26 18:40:07 -05002259 audit_log_untrustedstring(ab, get_task_comm(comm, current));
2260 audit_log_d_path_exe(ab, current->mm);
Eric Parisb24a30a2013-04-30 15:30:32 -04002261 audit_log_task_context(ab);
2262}
2263EXPORT_SYMBOL(audit_log_task_info);
2264
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002265/**
Kees Cook245d7362019-10-02 16:41:58 -07002266 * audit_log_path_denied - report a path restriction denial
2267 * @type: audit message type (AUDIT_ANOM_LINK, AUDIT_ANOM_CREAT, etc)
2268 * @operation: specific operation name
Kees Cooka51d9ea2012-07-25 17:29:08 -07002269 */
Kees Cook245d7362019-10-02 16:41:58 -07002270void audit_log_path_denied(int type, const char *operation)
Kees Cooka51d9ea2012-07-25 17:29:08 -07002271{
2272 struct audit_buffer *ab;
2273
Richard Guy Briggs15564ff2018-02-14 11:18:21 -05002274 if (!audit_enabled || audit_dummy_context())
Eric Parisb24a30a2013-04-30 15:30:32 -04002275 return;
2276
Kees Cook245d7362019-10-02 16:41:58 -07002277 /* Generate log with subject, operation, outcome. */
2278 ab = audit_log_start(audit_context(), GFP_KERNEL, type);
Sasha Levind1c7d972012-10-04 19:57:31 -04002279 if (!ab)
Richard Guy Briggs45b578f2018-02-14 11:18:22 -05002280 return;
Eric Parisb24a30a2013-04-30 15:30:32 -04002281 audit_log_format(ab, "op=%s", operation);
Paul Moore2a1fe212018-11-26 18:40:07 -05002282 audit_log_task_info(ab);
Eric Parisb24a30a2013-04-30 15:30:32 -04002283 audit_log_format(ab, " res=0");
Kees Cooka51d9ea2012-07-25 17:29:08 -07002284 audit_log_end(ab);
2285}
2286
Richard Guy Briggs4b7d2482019-01-22 17:06:39 -05002287/* global counter which is incremented every time something logs in */
2288static atomic_t session_id = ATOMIC_INIT(0);
2289
2290static int audit_set_loginuid_perm(kuid_t loginuid)
2291{
2292 /* if we are unset, we don't need privs */
2293 if (!audit_loginuid_set(current))
2294 return 0;
2295 /* if AUDIT_FEATURE_LOGINUID_IMMUTABLE means never ever allow a change*/
2296 if (is_audit_feature_set(AUDIT_FEATURE_LOGINUID_IMMUTABLE))
2297 return -EPERM;
2298 /* it is set, you need permission */
2299 if (!capable(CAP_AUDIT_CONTROL))
2300 return -EPERM;
2301 /* reject if this is not an unset and we don't allow that */
2302 if (is_audit_feature_set(AUDIT_FEATURE_ONLY_UNSET_LOGINUID)
2303 && uid_valid(loginuid))
2304 return -EPERM;
2305 return 0;
2306}
2307
2308static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid,
2309 unsigned int oldsessionid,
2310 unsigned int sessionid, int rc)
2311{
2312 struct audit_buffer *ab;
2313 uid_t uid, oldloginuid, loginuid;
2314 struct tty_struct *tty;
2315
2316 if (!audit_enabled)
2317 return;
2318
Richard Guy Briggs73e65b82019-03-19 15:23:29 -04002319 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_LOGIN);
Richard Guy Briggs4b7d2482019-01-22 17:06:39 -05002320 if (!ab)
2321 return;
2322
2323 uid = from_kuid(&init_user_ns, task_uid(current));
2324 oldloginuid = from_kuid(&init_user_ns, koldloginuid);
Zheng Yongjuna1b861f2020-12-11 16:42:54 +08002325 loginuid = from_kuid(&init_user_ns, kloginuid);
Richard Guy Briggs4b7d2482019-01-22 17:06:39 -05002326 tty = audit_get_tty();
2327
2328 audit_log_format(ab, "pid=%d uid=%u", task_tgid_nr(current), uid);
2329 audit_log_task_context(ab);
2330 audit_log_format(ab, " old-auid=%u auid=%u tty=%s old-ses=%u ses=%u res=%d",
2331 oldloginuid, loginuid, tty ? tty_name(tty) : "(none)",
2332 oldsessionid, sessionid, !rc);
2333 audit_put_tty(tty);
2334 audit_log_end(ab);
2335}
2336
2337/**
2338 * audit_set_loginuid - set current task's loginuid
2339 * @loginuid: loginuid value
2340 *
2341 * Returns 0.
2342 *
2343 * Called (set) from fs/proc/base.c::proc_loginuid_write().
2344 */
2345int audit_set_loginuid(kuid_t loginuid)
2346{
2347 unsigned int oldsessionid, sessionid = AUDIT_SID_UNSET;
2348 kuid_t oldloginuid;
2349 int rc;
2350
2351 oldloginuid = audit_get_loginuid(current);
2352 oldsessionid = audit_get_sessionid(current);
2353
2354 rc = audit_set_loginuid_perm(loginuid);
2355 if (rc)
2356 goto out;
2357
2358 /* are we setting or clearing? */
2359 if (uid_valid(loginuid)) {
2360 sessionid = (unsigned int)atomic_inc_return(&session_id);
2361 if (unlikely(sessionid == AUDIT_SID_UNSET))
2362 sessionid = (unsigned int)atomic_inc_return(&session_id);
2363 }
2364
2365 current->sessionid = sessionid;
2366 current->loginuid = loginuid;
2367out:
2368 audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc);
2369 return rc;
2370}
2371
Kees Cooka51d9ea2012-07-25 17:29:08 -07002372/**
Richard Guy Briggsb48345a2019-05-10 12:21:49 -04002373 * audit_signal_info - record signal info for shutting down audit subsystem
2374 * @sig: signal value
2375 * @t: task being signaled
2376 *
2377 * If the audit subsystem is being terminated, record the task (pid)
2378 * and uid that is doing that.
2379 */
2380int audit_signal_info(int sig, struct task_struct *t)
2381{
2382 kuid_t uid = current_uid(), auid;
2383
2384 if (auditd_test_task(t) &&
2385 (sig == SIGTERM || sig == SIGHUP ||
2386 sig == SIGUSR1 || sig == SIGUSR2)) {
2387 audit_sig_pid = task_tgid_nr(current);
2388 auid = audit_get_loginuid(current);
2389 if (uid_valid(auid))
2390 audit_sig_uid = auid;
2391 else
2392 audit_sig_uid = uid;
Paul Moore63269482021-09-29 11:01:21 -04002393 security_current_getsecid_subj(&audit_sig_sid);
Richard Guy Briggsb48345a2019-05-10 12:21:49 -04002394 }
2395
2396 return audit_signal_info_syscall(t);
2397}
2398
2399/**
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002400 * audit_log_end - end one audit record
2401 * @ab: the audit_buffer
2402 *
Paul Moore4aa838722016-11-29 16:53:24 -05002403 * We can not do a netlink send inside an irq context because it blocks (last
2404 * arg, flags, is not set to MSG_DONTWAIT), so the audit buffer is placed on a
Davidlohr Buesoc1de4462021-01-14 16:12:01 -08002405 * queue and a kthread is scheduled to remove them from the queue outside the
Paul Moore4aa838722016-11-29 16:53:24 -05002406 * irq context. May be called in any context.
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002407 */
David Woodhouseb7d11252005-05-19 10:56:58 +01002408void audit_log_end(struct audit_buffer *ab)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002409{
Paul Moore5b523302017-03-21 11:26:35 -04002410 struct sk_buff *skb;
2411 struct nlmsghdr *nlh;
2412
Linus Torvalds1da177e2005-04-16 15:20:36 -07002413 if (!ab)
2414 return;
Paul Moore5b523302017-03-21 11:26:35 -04002415
2416 if (audit_rate_check()) {
2417 skb = ab->skb;
Eric Parisf3d357b2008-04-18 10:02:28 -04002418 ab->skb = NULL;
Paul Moore5b523302017-03-21 11:26:35 -04002419
2420 /* setup the netlink header, see the comments in
2421 * kauditd_send_multicast_skb() for length quirks */
2422 nlh = nlmsg_hdr(skb);
2423 nlh->nlmsg_len = skb->len - NLMSG_HDRLEN;
2424
2425 /* queue the netlink packet and poke the kauditd thread */
2426 skb_queue_tail(&audit_queue, skb);
2427 wake_up_interruptible(&kauditd_wait);
2428 } else
2429 audit_log_lost("rate limit exceeded");
2430
Chris Wright16e19042005-05-06 15:53:34 +01002431 audit_buffer_free(ab);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002432}
2433
Randy Dunlapb0dd25a2005-09-13 12:47:11 -07002434/**
2435 * audit_log - Log an audit record
2436 * @ctx: audit context
2437 * @gfp_mask: type of allocation
2438 * @type: audit message type
2439 * @fmt: format string to use
2440 * @...: variable parameters matching the format string
2441 *
2442 * This is a convenience function that calls audit_log_start,
2443 * audit_log_vformat, and audit_log_end. It may be called
2444 * in any context.
2445 */
Daniel Walker5600b892007-10-18 03:06:10 -07002446void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
David Woodhouse9ad9ad32005-06-22 15:04:33 +01002447 const char *fmt, ...)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002448{
2449 struct audit_buffer *ab;
2450 va_list args;
2451
David Woodhouse9ad9ad32005-06-22 15:04:33 +01002452 ab = audit_log_start(ctx, gfp_mask, type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002453 if (ab) {
2454 va_start(args, fmt);
2455 audit_log_vformat(ab, fmt, args);
2456 va_end(args);
2457 audit_log_end(ab);
2458 }
2459}
lorenzo@gnu.orgbf45da92006-03-09 00:33:47 +01002460
2461EXPORT_SYMBOL(audit_log_start);
2462EXPORT_SYMBOL(audit_log_end);
2463EXPORT_SYMBOL(audit_log_format);
2464EXPORT_SYMBOL(audit_log);