Problem: nil pointer error with legacy tx format

CHANGELOG.md

@@ -78,6 +78,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (rpc) [#558](https://github.com/crypto-org-chain/ethermint/pull/558) New tracer in predecessors to trace balance correctly when `debug_traceTransaction`.
 * (rpc) [#559](https://github.com/crypto-org-chain/ethermint/pull/559) Use basefee of transaction height instead of minus one height when `debug_traceTransaction`.
 * (ante) [#560](https://github.com/crypto-org-chain/ethermint/pull/560) Check gasWanted only in checkTx mode.
+* (rpc) [#]() Fix nil pointer panic with legacy transaction format.
 
 ### Improvements
 

x/evm/types/eth.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 
 	errorsmod "cosmossdk.io/errors"
+	errortypes "github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	ethtypes "github.com/ethereum/go-ethereum/core/types"
 	"github.com/evmos/ethermint/types"
@@ -60,6 +61,9 @@ func (tx *EthereumTx) UnmarshalJSON(bz []byte) error {
 }
 
 func (tx EthereumTx) MarshalJSON() ([]byte, error) {
+	if tx.Transaction == nil {
+		return []byte("null"), nil
+	}
 	bz, err := tx.MarshalBinary()
 	if err != nil {
 		return nil, err
@@ -68,6 +72,10 @@ func (tx EthereumTx) MarshalJSON() ([]byte, error) {
 }
 
 func (tx EthereumTx) Validate() error {
+	if tx.Transaction == nil {
+		return errorsmod.Wrapf(errortypes.ErrInvalidRequest, "raw tx is missing")
+	}
+
 	// prevent txs with 0 gas to fill up the mempool
 	if tx.Gas() == 0 {
 		return errorsmod.Wrap(ErrInvalidGasLimit, "gas limit must not be zero")