--- a/sys/netgraph/fec/ng_fec.c
+++ b/sys/netgraph/fec/ng_fec.c
@@ -273,8 +273,9 @@ ng_fec_get_unit(int *unit)
 		if (newarray == NULL)
 			return (ENOMEM);
-		bcopy(ng_fec_units, newarray,
-		    ng_fec_units_len * sizeof(*ng_fec_units));
+		if (ng_fec_units != NULL)
+			bcopy(ng_fec_units, newarray,
+			    ng_fec_units_len * sizeof(*ng_fec_units));
 		for (i = ng_fec_units_len; i < newlen; i++)
 			newarray[i] = ~0;
 		if (ng_fec_units != NULL)