Merge pull request #6136 from m-Peter/evm-dry-run-create2-bug

Add a buffer gas of "all but one 64th" for gas used on `EVM.dryRun`

fvm/evm/emulator/emulator.go

@@ -256,9 +256,21 @@ func (bl *BlockView) DryRunTransaction(
 	// return without commiting the state
 	txResult, err := proc.run(msg, tx.Hash(), 0, tx.Type())
 	if txResult.Successful() {
+		// As mentioned in https://github.com/ethereum/EIPs/blob/master/EIPS/eip-150.md#specification
+		// Define "all but one 64th" of N as N - floor(N / 64).
+		// If a call asks for more gas than the maximum allowed amount
+		// (i.e. the total amount of gas remaining in the parent after subtracting
+		// the gas cost of the call and memory expansion), do not return an OOG error;
+		// instead, if a call asks for more gas than all but one 64th of the maximum
+		// allowed amount, call with all but one 64th of the maximum allowed amount of
+		// gas (this is equivalent to a version of EIP-901 plus EIP-1142).
+		// CREATE only provides all but one 64th of the parent gas to the child call.
+		txResult.GasConsumed = AddOne64th(txResult.GasConsumed)
+
 		// Adding `gethParams.SstoreSentryGasEIP2200` is needed for this condition:
 		// https://github.com/onflow/go-ethereum/blob/master/core/vm/operations_acl.go#L29-L32
 		txResult.GasConsumed += gethParams.SstoreSentryGasEIP2200
+
 		// Take into account any gas refunds, which are calculated only after
 		// transaction execution.
 		txResult.GasConsumed += txResult.GasRefund
@@ -587,3 +599,8 @@ func (proc *procedure) run(
 	}
 	return &res, nil
 }
+
+func AddOne64th(n uint64) uint64 {
+	// NOTE: Go's integer division floors, but that is desirable here
+	return n + (n / 64)
+}

fvm/evm/evm_test.go

@@ -25,6 +25,7 @@ import (
 	"github.com/onflow/flow-go/fvm/crypto"
 	envMock "github.com/onflow/flow-go/fvm/environment/mock"
 	"github.com/onflow/flow-go/fvm/evm"
+	"github.com/onflow/flow-go/fvm/evm/emulator"
 	"github.com/onflow/flow-go/fvm/evm/stdlib"
 	"github.com/onflow/flow-go/fvm/evm/testutils"
 	. "github.com/onflow/flow-go/fvm/evm/testutils"
@@ -1534,9 +1535,10 @@ func TestDryRun(t *testing.T) {
 				// Make sure that gas consumed from `EVM.dryRun` is bigger
 				// than the actual gas consumption of the equivalent
 				// `EVM.run`.
+				totalGas := emulator.AddOne64th(res.GasConsumed) + gethParams.SstoreSentryGasEIP2200
 				require.Equal(
 					t,
-					res.GasConsumed+gethParams.SstoreSentryGasEIP2200,
+					totalGas,
 					dryRunResult.GasConsumed,
 				)
 			})
@@ -1667,9 +1669,10 @@ func TestDryRun(t *testing.T) {
 				// Make sure that gas consumed from `EVM.dryRun` is bigger
 				// than the actual gas consumption of the equivalent
 				// `EVM.run`.
+				totalGas := emulator.AddOne64th(res.GasConsumed) + gethParams.SstoreSentryGasEIP2200
 				require.Equal(
 					t,
-					res.GasConsumed+gethParams.SstoreSentryGasEIP2200,
+					totalGas,
 					dryRunResult.GasConsumed,
 				)
 			})
@@ -1798,9 +1801,10 @@ func TestDryRun(t *testing.T) {
 				// Make sure that gas consumed from `EVM.dryRun` is bigger
 				// than the actual gas consumption of the equivalent
 				// `EVM.run`.
+				totalGas := emulator.AddOne64th(res.GasConsumed) + gethParams.SstoreSentryGasEIP2200 + gethParams.SstoreClearsScheduleRefundEIP3529
 				require.Equal(
 					t,
-					res.GasConsumed+gethParams.SstoreSentryGasEIP2200+gethParams.SstoreClearsScheduleRefundEIP3529,
+					totalGas,
 					dryRunResult.GasConsumed,
 				)
 			})