From bcb4802127f075b01187f92ff01f3695a9ea79d6 Mon Sep 17 00:00:00 2001
From: Pablo Carranza Velez <pablo@edgeandnode.com>
Date: Fri, 21 Oct 2022 13:51:53 -0300
Subject: [PATCH] fix: ensure l2Counterpart is nonzero (C4 M-201)

---
 contracts/gateway/L1GraphTokenGateway.sol | 1 +
 1 file changed, 1 insertion(+)

diff --git a/contracts/gateway/L1GraphTokenGateway.sol b/contracts/gateway/L1GraphTokenGateway.sol
index fbcbcf724..3fcb08a94 100644
--- a/contracts/gateway/L1GraphTokenGateway.sol
+++ b/contracts/gateway/L1GraphTokenGateway.sol
@@ -72,6 +72,7 @@ contract L1GraphTokenGateway is GraphTokenGateway, L1ArbitrumMessenger {
      */
     modifier onlyL2Counterpart() {
         require(inbox != address(0), "INBOX_NOT_SET");
+        require(l2Counterpart != address(0), "L2_COUNTERPART_NOT_SET");
 
         // a message coming from the counterpart gateway was executed by the bridge
         IBridge bridge = IInbox(inbox).bridge();