diff --git a/src/MESA_jump_layer.cpp b/src/MESA_jump_layer.cpp
index 34a05b1..8560061 100644
--- a/src/MESA_jump_layer.cpp
+++ b/src/MESA_jump_layer.cpp
@@ -1187,6 +1187,7 @@ static int vlan8021q_jump_to_layer(const char *raw_data,  int raw_layer_type, in
 		/* QinQ */
 		case ETH_P_8021Q:
 			snprintf(_g_mesa_jump_layer_last_error, PIPE_BUF, "vlan8021q_jump_to_layer(): multiple VLAN combine to one layer!");
+			skip_len = -1;
 			assert(0);
 		break;