From 6c97c325ff6d8442b0c168cdb5fd0a4b4ba0340e Mon Sep 17 00:00:00 2001
From: Xin LI <delphij@FreeBSD.org>
Date: Mon, 30 Jun 2008 15:21:42 +0000
Subject: [PATCH] Avoid NULL deference.

Reviewed by:	ivoras
---
 sys/geom/virstor/g_virstor.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sys/geom/virstor/g_virstor.c b/sys/geom/virstor/g_virstor.c
index dfbe5c6aae3b..1de3d5ae28e4 100644
--- a/sys/geom/virstor/g_virstor.c
+++ b/sys/geom/virstor/g_virstor.c
@@ -225,6 +225,11 @@ virstor_ctl_stop(struct gctl_req *req, struct g_class *cp)
 
 		sprintf(param, "arg%d", i);
 		name = gctl_get_asciiparam(req, param);
+		if (name == NULL) {
+			gctl_error(req, "No 'arg%d' argument", i);
+			g_topology_unlock();
+			return;
+		}
 		sc = virstor_find_geom(cp, name);
 		LOG_MSG(LVL_INFO, "Stopping %s by the userland command",
 		    sc->geom->name);