diff --git a/src/vnet/dev/api.c b/src/vnet/dev/api.c
index 260bc7b..72811f5 100644
--- a/src/vnet/dev/api.c
+++ b/src/vnet/dev/api.c
@@ -90,9 +90,10 @@
     }
   dev->description = dev_desc;
 
-  for (vnet_dev_arg_t *a = driver->registration->args;
-       a->type != VNET_DEV_ARG_END; a++)
-    vec_add1 (dev->args, *a);
+  if (driver->registration->args)
+    for (vnet_dev_arg_t *a = driver->registration->args;
+	 a->type != VNET_DEV_ARG_END; a++)
+      vec_add1 (dev->args, *a);
 
   if (args->args)
     {
diff --git a/src/vnet/dev/port.c b/src/vnet/dev/port.c
index b3f4035..0363ea4 100644
--- a/src/vnet/dev/port.c
+++ b/src/vnet/dev/port.c
@@ -267,8 +267,9 @@
   port->rx_node = *args->rx_node;
   port->tx_node = *args->tx_node;
 
-  for (vnet_dev_arg_t *a = args->port.args; a->type != VNET_DEV_ARG_END; a++)
-    vec_add1 (port->args, *a);
+  if (args->port.args)
+    for (vnet_dev_arg_t *a = args->port.args; a->type != VNET_DEV_ARG_END; a++)
+      vec_add1 (port->args, *a);
 
   /* defaults out of port attributes */
   port->max_rx_frame_size = args->port.attr.max_supported_rx_frame_size;