[PATCH] PPID filtering fix

On Thu, Sep 28, 2006 at 04:03:06PM -0400, Eric Paris wrote:
> After some looking I did not see a way to get into audit_log_exit
> without having set the ppid.  So I am dropping the set from there and
> only doing it at the beginning.
>
> Please comment/ack/nak as soon as possible.

Ehh...  That's one hell of an overhead to be had ;-/  Let's be lazy.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

kernel/auditsc.c

@@ -278,8 +278,11 @@ static int audit_filter_rules(struct task_struct *tsk,
 			result = audit_comparator(tsk->pid, f->op, f->val);
 			break;
 		case AUDIT_PPID:
-			if (ctx)
+			if (ctx) {
+				if (!ctx->ppid)
+					ctx->ppid = sys_getppid();
 				result = audit_comparator(ctx->ppid, f->op, f->val);
+			}
 			break;
 		case AUDIT_UID:
 			result = audit_comparator(tsk->uid, f->op, f->val);
@@ -795,7 +798,8 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
 
 	/* tsk == current */
 	context->pid = tsk->pid;
-	context->ppid = sys_getppid();	/* sic.  tsk == current in all cases */
+	if (!context->ppid)
+		context->ppid = sys_getppid();
 	context->uid = tsk->uid;
 	context->gid = tsk->gid;
 	context->euid = tsk->euid;
@@ -1137,6 +1141,7 @@ void audit_syscall_entry(int arch, int major,
 	context->ctime      = CURRENT_TIME;
 	context->in_syscall = 1;
 	context->auditable  = !!(state == AUDIT_RECORD_CONTEXT);
+	context->ppid       = 0;
 }
 
 /**