drm/ttm: make sure format string cannot leak in

While zone->name is currently hard coded, the call to kobject_init_and_add()
should follow the more defensive argument list usage (as already done in
other places in ttm_memory.c) where "%s" is used instead of directly passing
in a variable as a format string.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/ttm/ttm_memory.c

@@ -300,7 +300,8 @@ static int ttm_mem_init_highmem_zone(struct ttm_mem_global *glob,
 	zone->glob = glob;
 	glob->zone_highmem = zone;
 	ret = kobject_init_and_add(
-		&zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, zone->name);
+		&zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, "%s",
+		zone->name);
 	if (unlikely(ret != 0)) {
 		kobject_put(&zone->kobj);
 		return ret;