2007-08-07 23:01:57

by Al Viro

Subject: [PATCH] fix oops in __audit_signal_info()

Check for audit_signals is misplaced and check for
audit_dummy_context() is missing; as the result, if we send
signal to auditd from task with NULL ->audit_context while
we have audit_signals != 0 we end up with an oops.

Signed-off-by: Al Viro <[email protected]>
---
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index a777d37..3401293 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1992,19 +1992,19 @@ int __audit_signal_info(int sig, struct task_struct *t)
extern uid_t audit_sig_uid;
extern u32 audit_sig_sid;

- if (audit_pid && t->tgid == audit_pid &&
- (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1)) {
- audit_sig_pid = tsk->pid;
- if (ctx)
- audit_sig_uid = ctx->loginuid;
- else
- audit_sig_uid = tsk->uid;
- selinux_get_task_sid(tsk, &audit_sig_sid);
+ if (audit_pid && t->tgid == audit_pid) {
+ if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1) {
+ audit_sig_pid = tsk->pid;
+ if (ctx)
+ audit_sig_uid = ctx->loginuid;
+ else
+ audit_sig_uid = tsk->uid;
+ selinux_get_task_sid(tsk, &audit_sig_sid);
+ }
+ if (!audit_signals || audit_dummy_context())
+ return 0;
}

- if (!audit_signals) /* audit_context checked in wrapper */
- return 0;
-
/* optimize the common case by putting first signal recipient directly
* in audit_context */
if (!ctx->target_pid) {

2007-08-08 01:24:45

by James Morris

Subject: Re: [PATCH] fix oops in __audit_signal_info()

On Wed, 8 Aug 2007, Al Viro wrote:

> Check for audit_signals is misplaced and check for
> audit_dummy_context() is missing; as the result, if we send
> signal to auditd from task with NULL ->audit_context while
> we have audit_signals != 0 we end up with an oops.
>
> Signed-off-by: Al Viro <[email protected]>

Acked-by: James Morris <[email protected]>



--
James Morris
<[email protected]>