Index: samba/source/smbd/service.c
===================================================================
--- samba/source/smbd/service.c.orig
+++ samba/source/smbd/service.c
@@ -836,6 +836,15 @@ static connection_struct *make_connectio
 				      get_current_username(),
 				      current_user_info.domain,
 				      s, sizeof(s));
+
+		if (strlen(s) == 0) {
+			DEBUG(6, ("service [%s] did not resolve to a path\n",
+				    lp_servicename(snum)));
+			conn_free(conn);
+			*status = NT_STATUS_BAD_NETWORK_NAME;
+			return NULL;
+		}
+
 		set_conn_connectpath(conn,s);
 		DEBUG(3,("Connect path is '%s' for service [%s]\n",s,
 			 lp_servicename(snum)));