Limit Refuel to 1 GAS

src/neo/SmartContract/ApplicationEngine.cs

@@ -27,6 +27,7 @@ public partial class ApplicationEngine : ExecutionEngine
         /// The maximum cost that can be spent when a contract is executed in test mode.
         /// </summary>
         public const long TestModeGas = 20_00000000;
+        private const long MAX_REFUEL = 1_00000000;
 
         /// <summary>
         /// Triggered when a contract calls System.Runtime.Notify.
@@ -41,6 +42,7 @@ public partial class ApplicationEngine : ExecutionEngine
         private static IApplicationEngineProvider applicationEngineProvider;
         private static Dictionary<uint, InteropDescriptor> services;
         private long gas_amount;
+        private long gas_refuel = 0;
         private List<NotifyEventArgs> notifications;
         private List<IDisposable> disposables;
         private readonly Dictionary<UInt160, int> invocationCounter = new();
@@ -160,6 +162,9 @@ internal void Refuel(long gas)
         {
             checked
             {
+                gas_refuel += gas;
+                if (gas_refuel > MAX_REFUEL)
+                    throw new InvalidOperationException();
                 gas_amount += gas;
             }
         }

src/neo/SmartContract/Native/GasToken.cs

@@ -40,7 +40,7 @@ internal override async ContractTask OnPersist(ApplicationEngine engine)
         [ContractMethod(CpuFee = 1 << 15, RequiredCallFlags = CallFlags.States | CallFlags.AllowNotify)]
         private async ContractTask Refuel(ApplicationEngine engine, UInt160 account, long amount)
         {
-            if (amount < 0) throw new ArgumentOutOfRangeException(nameof(amount));
+            if (amount <= 0) throw new ArgumentOutOfRangeException(nameof(amount));
             if (!engine.CheckWitnessInternal(account)) throw new InvalidOperationException();
             await Burn(engine, account, amount);
             engine.Refuel(amount);