unit test

x/evm/ante/fee.go

@@ -48,7 +48,7 @@ func (fc EVMFeeCheckDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate b
 		return ctx, sdkerrors.ErrInsufficientFee
 	}
 	if txData.GetGasTipCap().Sign() < 0 {
-		return ctx, sdkerrors.Wrapf(sdkerrors.ErrInvalidRequest, "gas tip cap cannot be negative: %s", txData.GetGasTipCap())
+		return ctx, sdkerrors.Wrapf(sdkerrors.ErrInvalidRequest, "gas fee cap cannot be negative")
 	}
 
 	// if EVM version is Cancun or later, and the transaction contains at least one blob, we need to

x/evm/ante/fee_test.go

@@ -112,6 +112,24 @@ func TestEVMFeeCheckDecorator(t *testing.T) {
 		return ctx, nil
 	})
 	require.NotNil(t, err)
+
+	// should fail because of negative gas tip cap
+	txData.GasTipCap = big.NewInt(-1)
+	txData.GasFeeCap = big.NewInt(10000000000000)
+	tx, err = ethtypes.SignTx(ethtypes.NewTx(&txData), signer, key)
+	require.Nil(t, err)
+	typedTx = newDynamicFeeTxWithoutValidation(tx)
+	msg, err = types.NewMsgEVMTransaction(typedTx)
+	require.Nil(t, err)
+	ctx, err = preprocessor.AnteHandle(ctx, mockTx{msgs: []sdk.Msg{msg}}, false, func(ctx sdk.Context, _ sdk.Tx, _ bool) (sdk.Context, error) {
+		return ctx, nil
+	})
+	require.Nil(t, err)
+	_, err = handler.AnteHandle(ctx, mockTx{msgs: []sdk.Msg{msg}}, false, func(ctx sdk.Context, _ sdk.Tx, _ bool) (sdk.Context, error) {
+		return ctx, nil
+	})
+	require.NotNil(t, err)
+	require.Contains(t, err.Error(), "gas fee cap cannot be negative")
 }
 
 func TestCalculatePriorityScenarios(t *testing.T) {
@@ -227,3 +245,22 @@ func TestCalculatePriorityScenarios(t *testing.T) {
 		})
 	}
 }
+
+func newDynamicFeeTxWithoutValidation(tx *ethtypes.Transaction) *ethtx.DynamicFeeTx {
+	txData := &ethtx.DynamicFeeTx{
+		Nonce:    tx.Nonce(),
+		Data:     tx.Data(),
+		GasLimit: tx.Gas(),
+	}
+
+	v, r, s := tx.RawSignatureValues()
+	ethtx.SetConvertIfPresent(tx.To(), func(to *common.Address) string { return to.Hex() }, txData.SetTo)
+	ethtx.SetConvertIfPresent(tx.Value(), sdk.NewIntFromBigInt, txData.SetAmount)
+	ethtx.SetConvertIfPresent(tx.GasFeeCap(), sdk.NewIntFromBigInt, txData.SetGasFeeCap)
+	ethtx.SetConvertIfPresent(tx.GasTipCap(), sdk.NewIntFromBigInt, txData.SetGasTipCap)
+	al := tx.AccessList()
+	ethtx.SetConvertIfPresent(&al, ethtx.NewAccessList, txData.SetAccesses)
+
+	txData.SetSignatureValues(tx.ChainId(), v, r, s)
+	return txData
+}

x/evm/types/codec.go

@@ -94,10 +94,6 @@ func UnpackTxData(any *codectypes.Any) (ethtx.TxData, error) {
 		dtx := ethtx.DynamicFeeTx{}
 		if proto.Unmarshal(any.Value, &dtx) == nil {
 			// value is a dynamic fee tx
-			// check gas tip cap non-negative
-			if dtx.GasTipCap.Sign() < 0 {
-				return nil, fmt.Errorf("gas tip cap cannot be negative: %s", dtx.GasTipCap)
-			}
 			return &dtx, nil
 		}
 		btx := ethtx.BlobTx{}