[PATCH] -V2 Allow ppid filtering on syscall auditing

[Alexander Viro]

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.
  
> @@ -1116,6 +1115,7 @@ void audit_syscall_entry(int arch, int m
>  
>  	context->arch	    = arch;
>  	context->major      = major;
> +	context->ppid       = sys_getppid();

Ehh...  That's one hell of an overhead to be had ;-/  How about this?

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index fb83c5c..fd77ce4 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -278,8 +278,11 @@ static int audit_filter_rules(struct tas
 			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_
 
 	/* 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;
@@ -1132,6 +1136,7 @@ #endif
 	context->ctime      = CURRENT_TIME;
 	context->in_syscall = 1;
 	context->auditable  = !!(state == AUDIT_RECORD_CONTEXT);
+	context->ppid       = 0;
 }
 
 /**