--- a/sys/dev/disk/dm/dm_dev.c
+++ b/sys/dev/disk/dm/dm_dev.c
@@ -365,7 +365,7 @@
 	if (name)
 		strlcpy(dmv->name, name, sizeof(dmv->name));
 	if (uuid)
-		strncpy(dmv->uuid, uuid, sizeof(dmv->uuid));
+		strlcpy(dmv->uuid, uuid, sizeof(dmv->uuid));
 
 	return dmv;
 }