1 /* auditsc.c -- System-call auditing support
2 * Handles all system-call specific auditing features.
4 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
23 * Many of the ideas implemented here are from Stephen C. Tweedie,
24 * especially the idea of avoiding a copy by using getname.
26 * The method for actual interception of syscall entry and exit (not in
27 * this file -- see entry.S) is based on a GPL'd patch written by
28 * okir@suse.de and Copyright 2003 SuSE Linux AG.
32 #include <linux/init.h>
33 #include <asm/atomic.h>
34 #include <asm/types.h>
36 #include <linux/module.h>
37 #include <linux/mount.h>
38 #include <linux/socket.h>
39 #include <linux/audit.h>
40 #include <linux/personality.h>
41 #include <linux/time.h>
42 #include <linux/kthread.h>
43 #include <asm/unistd.h>
46 1 = put_count checking
47 2 = verbose put_count checking
51 /* No syscall auditing will take place unless audit_enabled != 0. */
52 extern int audit_enabled
;
54 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
55 * for saving names from getname(). */
56 #define AUDIT_NAMES 20
58 /* AUDIT_NAMES_RESERVED is the number of slots we reserve in the
59 * audit_context from being used for nameless inodes from
61 #define AUDIT_NAMES_RESERVED 7
63 /* At task start time, the audit_state is set in the audit_context using
64 a per-task filter. At syscall entry, the audit_state is augmented by
65 the syscall filter. */
67 AUDIT_DISABLED
, /* Do not create per-task audit_context.
68 * No syscall-specific audit records can
70 AUDIT_SETUP_CONTEXT
, /* Create the per-task audit_context,
71 * but don't necessarily fill it in at
72 * syscall entry time (i.e., filter
74 AUDIT_BUILD_CONTEXT
, /* Create the per-task audit_context,
75 * and always fill it in at syscall
76 * entry time. This makes a full
77 * syscall record available if some
78 * other part of the kernel decides it
79 * should be recorded. */
80 AUDIT_RECORD_CONTEXT
/* Create the per-task audit_context,
81 * always fill it in at syscall entry
82 * time, and always write out the audit
83 * record at syscall exit time. */
86 /* When fs/namei.c:getname() is called, we store the pointer in name and
87 * we don't let putname() free it (instead we free all of the saved
88 * pointers at syscall exit time).
90 * Further, in fs/namei.c:path_lookup() we store the inode and device. */
102 struct audit_aux_data
{
103 struct audit_aux_data
*next
;
107 #define AUDIT_AUX_IPCPERM 0
109 struct audit_aux_data_ipcctl
{
110 struct audit_aux_data d
;
112 unsigned long qbytes
;
118 struct audit_aux_data_socketcall
{
119 struct audit_aux_data d
;
121 unsigned long args
[0];
124 struct audit_aux_data_sockaddr
{
125 struct audit_aux_data d
;
130 struct audit_aux_data_path
{
131 struct audit_aux_data d
;
132 struct dentry
*dentry
;
133 struct vfsmount
*mnt
;
136 /* The per-task audit context. */
137 struct audit_context
{
138 int in_syscall
; /* 1 if task is in a syscall */
139 enum audit_state state
;
140 unsigned int serial
; /* serial number for record */
141 struct timespec ctime
; /* time of syscall entry */
142 uid_t loginuid
; /* login uid (identity) */
143 int major
; /* syscall number */
144 unsigned long argv
[4]; /* syscall arguments */
145 int return_valid
; /* return code is valid */
146 long return_code
;/* syscall return code */
147 int auditable
; /* 1 if record should be written */
149 struct audit_names names
[AUDIT_NAMES
];
151 struct vfsmount
* pwdmnt
;
152 struct audit_context
*previous
; /* For nested syscalls */
153 struct audit_aux_data
*aux
;
155 /* Save things to print about task_struct */
157 uid_t uid
, euid
, suid
, fsuid
;
158 gid_t gid
, egid
, sgid
, fsgid
;
159 unsigned long personality
;
169 /* There are three lists of rules -- one to search at task creation
170 * time, one to search at syscall entry time, and another to search at
171 * syscall exit time. */
172 static struct list_head audit_filter_list
[AUDIT_NR_FILTERS
] = {
173 LIST_HEAD_INIT(audit_filter_list
[0]),
174 LIST_HEAD_INIT(audit_filter_list
[1]),
175 LIST_HEAD_INIT(audit_filter_list
[2]),
176 LIST_HEAD_INIT(audit_filter_list
[3]),
177 LIST_HEAD_INIT(audit_filter_list
[4]),
178 #if AUDIT_NR_FILTERS != 5
179 #error Fix audit_filter_list initialiser
184 struct list_head list
;
186 struct audit_rule rule
;
189 extern int audit_pid
;
191 /* Check to see if two rules are identical. It is called from
192 * audit_del_rule during AUDIT_DEL. */
193 static int audit_compare_rule(struct audit_rule
*a
, struct audit_rule
*b
)
197 if (a
->flags
!= b
->flags
)
200 if (a
->action
!= b
->action
)
203 if (a
->field_count
!= b
->field_count
)
206 for (i
= 0; i
< a
->field_count
; i
++) {
207 if (a
->fields
[i
] != b
->fields
[i
]
208 || a
->values
[i
] != b
->values
[i
])
212 for (i
= 0; i
< AUDIT_BITMASK_SIZE
; i
++)
213 if (a
->mask
[i
] != b
->mask
[i
])
219 /* Note that audit_add_rule and audit_del_rule are called via
220 * audit_receive() in audit.c, and are protected by
221 * audit_netlink_sem. */
222 static inline void audit_add_rule(struct audit_entry
*entry
,
223 struct list_head
*list
)
225 if (entry
->rule
.flags
& AUDIT_FILTER_PREPEND
) {
226 entry
->rule
.flags
&= ~AUDIT_FILTER_PREPEND
;
227 list_add_rcu(&entry
->list
, list
);
229 list_add_tail_rcu(&entry
->list
, list
);
233 static void audit_free_rule(struct rcu_head
*head
)
235 struct audit_entry
*e
= container_of(head
, struct audit_entry
, rcu
);
239 /* Note that audit_add_rule and audit_del_rule are called via
240 * audit_receive() in audit.c, and are protected by
241 * audit_netlink_sem. */
242 static inline int audit_del_rule(struct audit_rule
*rule
,
243 struct list_head
*list
)
245 struct audit_entry
*e
;
247 /* Do not use the _rcu iterator here, since this is the only
248 * deletion routine. */
249 list_for_each_entry(e
, list
, list
) {
250 if (!audit_compare_rule(rule
, &e
->rule
)) {
251 list_del_rcu(&e
->list
);
252 call_rcu(&e
->rcu
, audit_free_rule
);
256 return -ENOENT
; /* No matching rule */
259 /* Copy rule from user-space to kernel-space. Called during
261 static int audit_copy_rule(struct audit_rule
*d
, struct audit_rule
*s
)
265 if (s
->action
!= AUDIT_NEVER
266 && s
->action
!= AUDIT_POSSIBLE
267 && s
->action
!= AUDIT_ALWAYS
)
269 if (s
->field_count
< 0 || s
->field_count
> AUDIT_MAX_FIELDS
)
271 if ((s
->flags
& ~AUDIT_FILTER_PREPEND
) >= AUDIT_NR_FILTERS
)
275 d
->action
= s
->action
;
276 d
->field_count
= s
->field_count
;
277 for (i
= 0; i
< d
->field_count
; i
++) {
278 d
->fields
[i
] = s
->fields
[i
];
279 d
->values
[i
] = s
->values
[i
];
281 for (i
= 0; i
< AUDIT_BITMASK_SIZE
; i
++) d
->mask
[i
] = s
->mask
[i
];
285 static int audit_list_rules(void *_dest
)
289 struct audit_entry
*entry
;
296 down(&audit_netlink_sem
);
298 /* The *_rcu iterators not needed here because we are
299 always called with audit_netlink_sem held. */
300 for (i
=0; i
<AUDIT_NR_FILTERS
; i
++) {
301 list_for_each_entry(entry
, &audit_filter_list
[i
], list
)
302 audit_send_reply(pid
, seq
, AUDIT_LIST
, 0, 1,
303 &entry
->rule
, sizeof(entry
->rule
));
305 audit_send_reply(pid
, seq
, AUDIT_LIST
, 1, 1, NULL
, 0);
307 up(&audit_netlink_sem
);
311 int audit_receive_filter(int type
, int pid
, int uid
, int seq
, void *data
,
314 struct audit_entry
*entry
;
315 struct task_struct
*tsk
;
322 /* We can't just spew out the rules here because we might fill
323 * the available socket buffer space and deadlock waiting for
324 * auditctl to read from it... which isn't ever going to
325 * happen if we're actually running in the context of auditctl
326 * trying to _send_ the stuff */
328 dest
= kmalloc(2 * sizeof(int), GFP_KERNEL
);
334 tsk
= kthread_run(audit_list_rules
, dest
, "audit_list_rules");
341 if (!(entry
= kmalloc(sizeof(*entry
), GFP_KERNEL
)))
343 if (audit_copy_rule(&entry
->rule
, data
)) {
347 listnr
= entry
->rule
.flags
& ~AUDIT_FILTER_PREPEND
;
348 audit_add_rule(entry
, &audit_filter_list
[listnr
]);
349 audit_log(NULL
, GFP_KERNEL
, AUDIT_CONFIG_CHANGE
,
350 "auid=%u added an audit rule\n", loginuid
);
353 listnr
=((struct audit_rule
*)data
)->flags
& ~AUDIT_FILTER_PREPEND
;
354 if (listnr
>= AUDIT_NR_FILTERS
)
357 err
= audit_del_rule(data
, &audit_filter_list
[listnr
]);
359 audit_log(NULL
, GFP_KERNEL
, AUDIT_CONFIG_CHANGE
,
360 "auid=%u removed an audit rule\n", loginuid
);
369 /* Compare a task_struct with an audit_rule. Return 1 on match, 0
371 static int audit_filter_rules(struct task_struct
*tsk
,
372 struct audit_rule
*rule
,
373 struct audit_context
*ctx
,
374 enum audit_state
*state
)
378 for (i
= 0; i
< rule
->field_count
; i
++) {
379 u32 field
= rule
->fields
[i
] & ~AUDIT_NEGATE
;
380 u32 value
= rule
->values
[i
];
385 result
= (tsk
->pid
== value
);
388 result
= (tsk
->uid
== value
);
391 result
= (tsk
->euid
== value
);
394 result
= (tsk
->suid
== value
);
397 result
= (tsk
->fsuid
== value
);
400 result
= (tsk
->gid
== value
);
403 result
= (tsk
->egid
== value
);
406 result
= (tsk
->sgid
== value
);
409 result
= (tsk
->fsgid
== value
);
412 result
= (tsk
->personality
== value
);
416 result
= (ctx
->arch
== value
);
420 if (ctx
&& ctx
->return_valid
)
421 result
= (ctx
->return_code
== value
);
424 if (ctx
&& ctx
->return_valid
)
425 result
= (ctx
->return_valid
== AUDITSC_SUCCESS
);
429 for (j
= 0; j
< ctx
->name_count
; j
++) {
430 if (MAJOR(ctx
->names
[j
].dev
)==value
) {
439 for (j
= 0; j
< ctx
->name_count
; j
++) {
440 if (MINOR(ctx
->names
[j
].dev
)==value
) {
449 for (j
= 0; j
< ctx
->name_count
; j
++) {
450 if (ctx
->names
[j
].ino
== value
) {
460 result
= (ctx
->loginuid
== value
);
467 result
= (ctx
->argv
[field
-AUDIT_ARG0
]==value
);
471 if (rule
->fields
[i
] & AUDIT_NEGATE
)
476 switch (rule
->action
) {
477 case AUDIT_NEVER
: *state
= AUDIT_DISABLED
; break;
478 case AUDIT_POSSIBLE
: *state
= AUDIT_BUILD_CONTEXT
; break;
479 case AUDIT_ALWAYS
: *state
= AUDIT_RECORD_CONTEXT
; break;
484 /* At process creation time, we can determine if system-call auditing is
485 * completely disabled for this task. Since we only have the task
486 * structure at this point, we can only check uid and gid.
488 static enum audit_state
audit_filter_task(struct task_struct
*tsk
)
490 struct audit_entry
*e
;
491 enum audit_state state
;
494 list_for_each_entry_rcu(e
, &audit_filter_list
[AUDIT_FILTER_TASK
], list
) {
495 if (audit_filter_rules(tsk
, &e
->rule
, NULL
, &state
)) {
501 return AUDIT_BUILD_CONTEXT
;
504 /* At syscall entry and exit time, this filter is called if the
505 * audit_state is not low enough that auditing cannot take place, but is
506 * also not high enough that we already know we have to write an audit
507 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
509 static enum audit_state
audit_filter_syscall(struct task_struct
*tsk
,
510 struct audit_context
*ctx
,
511 struct list_head
*list
)
513 struct audit_entry
*e
;
514 enum audit_state state
;
515 int word
= AUDIT_WORD(ctx
->major
);
516 int bit
= AUDIT_BIT(ctx
->major
);
518 if (audit_pid
&& ctx
->pid
== audit_pid
)
519 return AUDIT_DISABLED
;
522 list_for_each_entry_rcu(e
, list
, list
) {
523 if ((e
->rule
.mask
[word
] & bit
) == bit
524 && audit_filter_rules(tsk
, &e
->rule
, ctx
, &state
)) {
530 return AUDIT_BUILD_CONTEXT
;
533 int audit_filter_user(int pid
, int type
)
535 struct task_struct
*tsk
;
536 struct audit_entry
*e
;
537 enum audit_state state
;
540 read_lock(&tasklist_lock
);
541 tsk
= find_task_by_pid(pid
);
543 get_task_struct(tsk
);
544 read_unlock(&tasklist_lock
);
550 list_for_each_entry_rcu(e
, &audit_filter_list
[AUDIT_FILTER_USER
], list
) {
551 if (audit_filter_rules(tsk
, &e
->rule
, NULL
, &state
)) {
552 if (state
== AUDIT_DISABLED
)
558 put_task_struct(tsk
);
560 return 1; /* Audit by default */
564 /* This should be called with task_lock() held. */
565 static inline struct audit_context
*audit_get_context(struct task_struct
*tsk
,
569 struct audit_context
*context
= tsk
->audit_context
;
571 if (likely(!context
))
573 context
->return_valid
= return_valid
;
574 context
->return_code
= return_code
;
576 if (context
->in_syscall
&& !context
->auditable
) {
577 enum audit_state state
;
578 state
= audit_filter_syscall(tsk
, context
, &audit_filter_list
[AUDIT_FILTER_EXIT
]);
579 if (state
== AUDIT_RECORD_CONTEXT
)
580 context
->auditable
= 1;
583 context
->pid
= tsk
->pid
;
584 context
->uid
= tsk
->uid
;
585 context
->gid
= tsk
->gid
;
586 context
->euid
= tsk
->euid
;
587 context
->suid
= tsk
->suid
;
588 context
->fsuid
= tsk
->fsuid
;
589 context
->egid
= tsk
->egid
;
590 context
->sgid
= tsk
->sgid
;
591 context
->fsgid
= tsk
->fsgid
;
592 context
->personality
= tsk
->personality
;
593 tsk
->audit_context
= NULL
;
597 static inline void audit_free_names(struct audit_context
*context
)
602 if (context
->auditable
603 ||context
->put_count
+ context
->ino_count
!= context
->name_count
) {
604 printk(KERN_ERR
"audit.c:%d(:%d): major=%d in_syscall=%d"
605 " name_count=%d put_count=%d"
606 " ino_count=%d [NOT freeing]\n",
608 context
->serial
, context
->major
, context
->in_syscall
,
609 context
->name_count
, context
->put_count
,
611 for (i
= 0; i
< context
->name_count
; i
++)
612 printk(KERN_ERR
"names[%d] = %p = %s\n", i
,
613 context
->names
[i
].name
,
614 context
->names
[i
].name
);
620 context
->put_count
= 0;
621 context
->ino_count
= 0;
624 for (i
= 0; i
< context
->name_count
; i
++)
625 if (context
->names
[i
].name
)
626 __putname(context
->names
[i
].name
);
627 context
->name_count
= 0;
631 mntput(context
->pwdmnt
);
633 context
->pwdmnt
= NULL
;
636 static inline void audit_free_aux(struct audit_context
*context
)
638 struct audit_aux_data
*aux
;
640 while ((aux
= context
->aux
)) {
641 if (aux
->type
== AUDIT_AVC_PATH
) {
642 struct audit_aux_data_path
*axi
= (void *)aux
;
646 context
->aux
= aux
->next
;
651 static inline void audit_zero_context(struct audit_context
*context
,
652 enum audit_state state
)
654 uid_t loginuid
= context
->loginuid
;
656 memset(context
, 0, sizeof(*context
));
657 context
->state
= state
;
658 context
->loginuid
= loginuid
;
661 static inline struct audit_context
*audit_alloc_context(enum audit_state state
)
663 struct audit_context
*context
;
665 if (!(context
= kmalloc(sizeof(*context
), GFP_KERNEL
)))
667 audit_zero_context(context
, state
);
671 /* Filter on the task information and allocate a per-task audit context
672 * if necessary. Doing so turns on system call auditing for the
673 * specified task. This is called from copy_process, so no lock is
675 int audit_alloc(struct task_struct
*tsk
)
677 struct audit_context
*context
;
678 enum audit_state state
;
680 if (likely(!audit_enabled
))
681 return 0; /* Return if not auditing. */
683 state
= audit_filter_task(tsk
);
684 if (likely(state
== AUDIT_DISABLED
))
687 if (!(context
= audit_alloc_context(state
))) {
688 audit_log_lost("out of memory in audit_alloc");
692 /* Preserve login uid */
693 context
->loginuid
= -1;
694 if (current
->audit_context
)
695 context
->loginuid
= current
->audit_context
->loginuid
;
697 tsk
->audit_context
= context
;
698 set_tsk_thread_flag(tsk
, TIF_SYSCALL_AUDIT
);
702 static inline void audit_free_context(struct audit_context
*context
)
704 struct audit_context
*previous
;
708 previous
= context
->previous
;
709 if (previous
|| (count
&& count
< 10)) {
711 printk(KERN_ERR
"audit(:%d): major=%d name_count=%d:"
712 " freeing multiple contexts (%d)\n",
713 context
->serial
, context
->major
,
714 context
->name_count
, count
);
716 audit_free_names(context
);
717 audit_free_aux(context
);
722 printk(KERN_ERR
"audit: freed %d contexts\n", count
);
725 static void audit_log_task_info(struct audit_buffer
*ab
)
727 char name
[sizeof(current
->comm
)];
728 struct mm_struct
*mm
= current
->mm
;
729 struct vm_area_struct
*vma
;
731 get_task_comm(name
, current
);
732 audit_log_format(ab
, " comm=");
733 audit_log_untrustedstring(ab
, name
);
738 down_read(&mm
->mmap_sem
);
741 if ((vma
->vm_flags
& VM_EXECUTABLE
) &&
743 audit_log_d_path(ab
, "exe=",
744 vma
->vm_file
->f_dentry
,
745 vma
->vm_file
->f_vfsmnt
);
750 up_read(&mm
->mmap_sem
);
753 static void audit_log_exit(struct audit_context
*context
)
756 struct audit_buffer
*ab
;
757 struct audit_aux_data
*aux
;
759 ab
= audit_log_start(context
, GFP_KERNEL
, AUDIT_SYSCALL
);
761 return; /* audit_panic has been called */
762 audit_log_format(ab
, "arch=%x syscall=%d",
763 context
->arch
, context
->major
);
764 if (context
->personality
!= PER_LINUX
)
765 audit_log_format(ab
, " per=%lx", context
->personality
);
766 if (context
->return_valid
)
767 audit_log_format(ab
, " success=%s exit=%ld",
768 (context
->return_valid
==AUDITSC_SUCCESS
)?"yes":"no",
769 context
->return_code
);
771 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
772 " pid=%d auid=%u uid=%u gid=%u"
773 " euid=%u suid=%u fsuid=%u"
774 " egid=%u sgid=%u fsgid=%u",
784 context
->euid
, context
->suid
, context
->fsuid
,
785 context
->egid
, context
->sgid
, context
->fsgid
);
786 audit_log_task_info(ab
);
789 for (aux
= context
->aux
; aux
; aux
= aux
->next
) {
791 ab
= audit_log_start(context
, GFP_KERNEL
, aux
->type
);
793 continue; /* audit_panic has been called */
797 struct audit_aux_data_ipcctl
*axi
= (void *)aux
;
799 " qbytes=%lx iuid=%u igid=%u mode=%x",
800 axi
->qbytes
, axi
->uid
, axi
->gid
, axi
->mode
);
803 case AUDIT_SOCKETCALL
: {
805 struct audit_aux_data_socketcall
*axs
= (void *)aux
;
806 audit_log_format(ab
, "nargs=%d", axs
->nargs
);
807 for (i
=0; i
<axs
->nargs
; i
++)
808 audit_log_format(ab
, " a%d=%lx", i
, axs
->args
[i
]);
811 case AUDIT_SOCKADDR
: {
812 struct audit_aux_data_sockaddr
*axs
= (void *)aux
;
814 audit_log_format(ab
, "saddr=");
815 audit_log_hex(ab
, axs
->a
, axs
->len
);
818 case AUDIT_AVC_PATH
: {
819 struct audit_aux_data_path
*axi
= (void *)aux
;
820 audit_log_d_path(ab
, "path=", axi
->dentry
, axi
->mnt
);
827 if (context
->pwd
&& context
->pwdmnt
) {
828 ab
= audit_log_start(context
, GFP_KERNEL
, AUDIT_CWD
);
830 audit_log_d_path(ab
, "cwd=", context
->pwd
, context
->pwdmnt
);
834 for (i
= 0; i
< context
->name_count
; i
++) {
835 ab
= audit_log_start(context
, GFP_KERNEL
, AUDIT_PATH
);
837 continue; /* audit_panic has been called */
839 audit_log_format(ab
, "item=%d", i
);
840 if (context
->names
[i
].name
) {
841 audit_log_format(ab
, " name=");
842 audit_log_untrustedstring(ab
, context
->names
[i
].name
);
844 audit_log_format(ab
, " flags=%x\n", context
->names
[i
].flags
);
846 if (context
->names
[i
].ino
!= (unsigned long)-1)
847 audit_log_format(ab
, " inode=%lu dev=%02x:%02x mode=%#o"
848 " ouid=%u ogid=%u rdev=%02x:%02x",
849 context
->names
[i
].ino
,
850 MAJOR(context
->names
[i
].dev
),
851 MINOR(context
->names
[i
].dev
),
852 context
->names
[i
].mode
,
853 context
->names
[i
].uid
,
854 context
->names
[i
].gid
,
855 MAJOR(context
->names
[i
].rdev
),
856 MINOR(context
->names
[i
].rdev
));
861 /* Free a per-task audit context. Called from copy_process and
862 * __put_task_struct. */
863 void audit_free(struct task_struct
*tsk
)
865 struct audit_context
*context
;
868 context
= audit_get_context(tsk
, 0, 0);
871 if (likely(!context
))
874 /* Check for system calls that do not go through the exit
875 * function (e.g., exit_group), then free context block. */
876 if (context
->in_syscall
&& context
->auditable
)
877 audit_log_exit(context
);
879 audit_free_context(context
);
882 /* Fill in audit context at syscall entry. This only happens if the
883 * audit context was created when the task was created and the state or
884 * filters demand the audit context be built. If the state from the
885 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
886 * then the record will be written at syscall exit time (otherwise, it
887 * will only be written if another part of the kernel requests that it
889 void audit_syscall_entry(struct task_struct
*tsk
, int arch
, int major
,
890 unsigned long a1
, unsigned long a2
,
891 unsigned long a3
, unsigned long a4
)
893 struct audit_context
*context
= tsk
->audit_context
;
894 enum audit_state state
;
898 /* This happens only on certain architectures that make system
899 * calls in kernel_thread via the entry.S interface, instead of
900 * with direct calls. (If you are porting to a new
901 * architecture, hitting this condition can indicate that you
902 * got the _exit/_leave calls backward in entry.S.)
906 * ppc64 yes (see arch/ppc64/kernel/misc.S)
908 * This also happens with vm86 emulation in a non-nested manner
909 * (entries without exits), so this case must be caught.
911 if (context
->in_syscall
) {
912 struct audit_context
*newctx
;
914 #if defined(__NR_vm86) && defined(__NR_vm86old)
915 /* vm86 mode should only be entered once */
916 if (major
== __NR_vm86
|| major
== __NR_vm86old
)
921 "audit(:%d) pid=%d in syscall=%d;"
922 " entering syscall=%d\n",
923 context
->serial
, tsk
->pid
, context
->major
, major
);
925 newctx
= audit_alloc_context(context
->state
);
927 newctx
->previous
= context
;
929 tsk
->audit_context
= newctx
;
931 /* If we can't alloc a new context, the best we
932 * can do is to leak memory (any pending putname
933 * will be lost). The only other alternative is
934 * to abandon auditing. */
935 audit_zero_context(context
, context
->state
);
938 BUG_ON(context
->in_syscall
|| context
->name_count
);
943 context
->arch
= arch
;
944 context
->major
= major
;
945 context
->argv
[0] = a1
;
946 context
->argv
[1] = a2
;
947 context
->argv
[2] = a3
;
948 context
->argv
[3] = a4
;
950 state
= context
->state
;
951 if (state
== AUDIT_SETUP_CONTEXT
|| state
== AUDIT_BUILD_CONTEXT
)
952 state
= audit_filter_syscall(tsk
, context
, &audit_filter_list
[AUDIT_FILTER_ENTRY
]);
953 if (likely(state
== AUDIT_DISABLED
))
956 context
->serial
= audit_serial();
957 context
->ctime
= CURRENT_TIME
;
958 context
->in_syscall
= 1;
959 context
->auditable
= !!(state
== AUDIT_RECORD_CONTEXT
);
962 /* Tear down after system call. If the audit context has been marked as
963 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
964 * filtering, or because some other part of the kernel write an audit
965 * message), then write out the syscall information. In call cases,
966 * free the names stored from getname(). */
967 void audit_syscall_exit(struct task_struct
*tsk
, int valid
, long return_code
)
969 struct audit_context
*context
;
971 get_task_struct(tsk
);
973 context
= audit_get_context(tsk
, valid
, return_code
);
976 /* Not having a context here is ok, since the parent may have
977 * called __put_task_struct. */
978 if (likely(!context
))
981 if (context
->in_syscall
&& context
->auditable
)
982 audit_log_exit(context
);
984 context
->in_syscall
= 0;
985 context
->auditable
= 0;
987 if (context
->previous
) {
988 struct audit_context
*new_context
= context
->previous
;
989 context
->previous
= NULL
;
990 audit_free_context(context
);
991 tsk
->audit_context
= new_context
;
993 audit_free_names(context
);
994 audit_free_aux(context
);
995 audit_zero_context(context
, context
->state
);
996 tsk
->audit_context
= context
;
998 put_task_struct(tsk
);
1001 /* Add a name to the list. Called from fs/namei.c:getname(). */
1002 void audit_getname(const char *name
)
1004 struct audit_context
*context
= current
->audit_context
;
1006 if (!context
|| IS_ERR(name
) || !name
)
1009 if (!context
->in_syscall
) {
1010 #if AUDIT_DEBUG == 2
1011 printk(KERN_ERR
"%s:%d(:%d): ignoring getname(%p)\n",
1012 __FILE__
, __LINE__
, context
->serial
, name
);
1017 BUG_ON(context
->name_count
>= AUDIT_NAMES
);
1018 context
->names
[context
->name_count
].name
= name
;
1019 context
->names
[context
->name_count
].ino
= (unsigned long)-1;
1020 ++context
->name_count
;
1021 if (!context
->pwd
) {
1022 read_lock(¤t
->fs
->lock
);
1023 context
->pwd
= dget(current
->fs
->pwd
);
1024 context
->pwdmnt
= mntget(current
->fs
->pwdmnt
);
1025 read_unlock(¤t
->fs
->lock
);
1030 /* Intercept a putname request. Called from
1031 * include/linux/fs.h:putname(). If we have stored the name from
1032 * getname in the audit context, then we delay the putname until syscall
1034 void audit_putname(const char *name
)
1036 struct audit_context
*context
= current
->audit_context
;
1039 if (!context
->in_syscall
) {
1040 #if AUDIT_DEBUG == 2
1041 printk(KERN_ERR
"%s:%d(:%d): __putname(%p)\n",
1042 __FILE__
, __LINE__
, context
->serial
, name
);
1043 if (context
->name_count
) {
1045 for (i
= 0; i
< context
->name_count
; i
++)
1046 printk(KERN_ERR
"name[%d] = %p = %s\n", i
,
1047 context
->names
[i
].name
,
1048 context
->names
[i
].name
);
1055 ++context
->put_count
;
1056 if (context
->put_count
> context
->name_count
) {
1057 printk(KERN_ERR
"%s:%d(:%d): major=%d"
1058 " in_syscall=%d putname(%p) name_count=%d"
1061 context
->serial
, context
->major
,
1062 context
->in_syscall
, name
, context
->name_count
,
1063 context
->put_count
);
1070 /* Store the inode and device from a lookup. Called from
1071 * fs/namei.c:path_lookup(). */
1072 void audit_inode(const char *name
, const struct inode
*inode
, unsigned flags
)
1075 struct audit_context
*context
= current
->audit_context
;
1077 if (!context
->in_syscall
)
1079 if (context
->name_count
1080 && context
->names
[context
->name_count
-1].name
1081 && context
->names
[context
->name_count
-1].name
== name
)
1082 idx
= context
->name_count
- 1;
1083 else if (context
->name_count
> 1
1084 && context
->names
[context
->name_count
-2].name
1085 && context
->names
[context
->name_count
-2].name
== name
)
1086 idx
= context
->name_count
- 2;
1088 /* FIXME: how much do we care about inodes that have no
1089 * associated name? */
1090 if (context
->name_count
>= AUDIT_NAMES
- AUDIT_NAMES_RESERVED
)
1092 idx
= context
->name_count
++;
1093 context
->names
[idx
].name
= NULL
;
1095 ++context
->ino_count
;
1098 context
->names
[idx
].flags
= flags
;
1099 context
->names
[idx
].ino
= inode
->i_ino
;
1100 context
->names
[idx
].dev
= inode
->i_sb
->s_dev
;
1101 context
->names
[idx
].mode
= inode
->i_mode
;
1102 context
->names
[idx
].uid
= inode
->i_uid
;
1103 context
->names
[idx
].gid
= inode
->i_gid
;
1104 context
->names
[idx
].rdev
= inode
->i_rdev
;
1107 void auditsc_get_stamp(struct audit_context
*ctx
,
1108 struct timespec
*t
, unsigned int *serial
)
1110 t
->tv_sec
= ctx
->ctime
.tv_sec
;
1111 t
->tv_nsec
= ctx
->ctime
.tv_nsec
;
1112 *serial
= ctx
->serial
;
1116 int audit_set_loginuid(struct task_struct
*task
, uid_t loginuid
)
1118 if (task
->audit_context
) {
1119 struct audit_buffer
*ab
;
1121 ab
= audit_log_start(NULL
, GFP_KERNEL
, AUDIT_LOGIN
);
1123 audit_log_format(ab
, "login pid=%d uid=%u "
1124 "old auid=%u new auid=%u",
1125 task
->pid
, task
->uid
,
1126 task
->audit_context
->loginuid
, loginuid
);
1129 task
->audit_context
->loginuid
= loginuid
;
1134 uid_t
audit_get_loginuid(struct audit_context
*ctx
)
1136 return ctx
? ctx
->loginuid
: -1;
1139 int audit_ipc_perms(unsigned long qbytes
, uid_t uid
, gid_t gid
, mode_t mode
)
1141 struct audit_aux_data_ipcctl
*ax
;
1142 struct audit_context
*context
= current
->audit_context
;
1144 if (likely(!context
))
1147 ax
= kmalloc(sizeof(*ax
), GFP_KERNEL
);
1151 ax
->qbytes
= qbytes
;
1156 ax
->d
.type
= AUDIT_IPC
;
1157 ax
->d
.next
= context
->aux
;
1158 context
->aux
= (void *)ax
;
1162 int audit_socketcall(int nargs
, unsigned long *args
)
1164 struct audit_aux_data_socketcall
*ax
;
1165 struct audit_context
*context
= current
->audit_context
;
1167 if (likely(!context
))
1170 ax
= kmalloc(sizeof(*ax
) + nargs
* sizeof(unsigned long), GFP_KERNEL
);
1175 memcpy(ax
->args
, args
, nargs
* sizeof(unsigned long));
1177 ax
->d
.type
= AUDIT_SOCKETCALL
;
1178 ax
->d
.next
= context
->aux
;
1179 context
->aux
= (void *)ax
;
1183 int audit_sockaddr(int len
, void *a
)
1185 struct audit_aux_data_sockaddr
*ax
;
1186 struct audit_context
*context
= current
->audit_context
;
1188 if (likely(!context
))
1191 ax
= kmalloc(sizeof(*ax
) + len
, GFP_KERNEL
);
1196 memcpy(ax
->a
, a
, len
);
1198 ax
->d
.type
= AUDIT_SOCKADDR
;
1199 ax
->d
.next
= context
->aux
;
1200 context
->aux
= (void *)ax
;
1204 int audit_avc_path(struct dentry
*dentry
, struct vfsmount
*mnt
)
1206 struct audit_aux_data_path
*ax
;
1207 struct audit_context
*context
= current
->audit_context
;
1209 if (likely(!context
))
1212 ax
= kmalloc(sizeof(*ax
), GFP_ATOMIC
);
1216 ax
->dentry
= dget(dentry
);
1217 ax
->mnt
= mntget(mnt
);
1219 ax
->d
.type
= AUDIT_AVC_PATH
;
1220 ax
->d
.next
= context
->aux
;
1221 context
->aux
= (void *)ax
;
1225 void audit_signal_info(int sig
, struct task_struct
*t
)
1227 extern pid_t audit_sig_pid
;
1228 extern uid_t audit_sig_uid
;
1230 if (unlikely(audit_pid
&& t
->pid
== audit_pid
)) {
1231 if (sig
== SIGTERM
|| sig
== SIGHUP
) {
1232 struct audit_context
*ctx
= current
->audit_context
;
1233 audit_sig_pid
= current
->pid
;
1235 audit_sig_uid
= ctx
->loginuid
;
1237 audit_sig_uid
= current
->uid
;