From 2fca9c3f7d359d730b93f456a034b6c809a47930 Mon Sep 17 00:00:00 2001
From: Erik Zhang <erik@neo.org>
Date: Wed, 4 Aug 2021 17:57:50 +0800
Subject: [PATCH] Allow calls from deployed contracts only

---
 src/neo/SmartContract/Native/GasToken.cs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/neo/SmartContract/Native/GasToken.cs b/src/neo/SmartContract/Native/GasToken.cs
index 39690c7df8..9cfc5c1ede 100644
--- a/src/neo/SmartContract/Native/GasToken.cs
+++ b/src/neo/SmartContract/Native/GasToken.cs
@@ -41,6 +41,8 @@ internal override async ContractTask OnPersist(ApplicationEngine engine)
         private async ContractTask Refuel(ApplicationEngine engine, UInt160 account, long amount)
         {
             if (amount <= 0) throw new ArgumentOutOfRangeException(nameof(amount));
+            if (ContractManagement.GetContract(engine.Snapshot, engine.CallingScriptHash) is null)
+                throw new InvalidOperationException();
             if (!engine.CheckWitnessInternal(account)) throw new InvalidOperationException();
             engine.Refuel(amount);
             await Burn(engine, account, amount);