Only account for execution gas in sanity checks (#250)

Author: hazim-j

internal/testutils/opmock.go

@@ -19,7 +19,7 @@ var (
 		"maxFeePerGas":         "0xa862145e",
 		"maxPriorityFeePerGas": "0xa8621440",
 		"paymasterAndData":     "0x",
-		"preVerificationGas":   "0xc869",
+		"preVerificationGas":   "0xc539",
 		"signature":            "0xa925dcc5e5131636e244d4405334c25f034ebdd85c0cb12e8cdb13c15249c2d466d0bade18e2cafd3513497f7f968dcbb63e519acd9b76dcae7acd61f11aa8421b",
 	}
 	MockByteCode = common.Hex2Bytes("6080604052")

pkg/modules/checks/gas.go

@@ -4,12 +4,24 @@ import (
 	"fmt"
 	"math/big"
 
+	"github.com/stackup-wallet/stackup-bundler/pkg/gas"
 	"github.com/stackup-wallet/stackup-bundler/pkg/userop"
 )
 
 // ValidateGasAvailable checks that the max available gas is less than the batch gas limit.
 func ValidateGasAvailable(op *userop.UserOperation, maxBatchGasLimit *big.Int) error {
-	if op.GetMaxGasAvailable().Cmp(maxBatchGasLimit) > 0 {
+	// This calculation ensures that we are only checking the gas used for execution. In rollups, the PVG also
+	// includes the L1 callData cost. If the L1 gas component spikes, it can cause the PVG value of legit ops
+	// to be greater than the maxBatchGasLimit. For non-rollups, the results would be the same as just calling
+	// op.GetMaxGasAvailable().
+	static, err := gas.NewDefaultOverhead().CalcPreVerificationGas(op)
+	if err != nil {
+		return err
+	}
+	mgl := big.NewInt(0).Sub(op.GetMaxGasAvailable(), op.PreVerificationGas)
+	mga := big.NewInt(0).Add(mgl, static)
+
+	if mga.Cmp(maxBatchGasLimit) > 0 {
 		return fmt.Errorf("gasLimit: exceeds maxBatchGasLimit of %s", maxBatchGasLimit.String())
 	}