Bad data may be generated due to error returned during the execution of evm transaction

[summerpro]

System info: [Include Ethermint commit, operating system name, and other relevant details]

• development

Steps to reproduce:

1. An evm transaction is executed, and the evm.Create or evm.Call method is successfully executed, the "storage" data and "code" data in CommitStateDB have been modified.
2. Function "csdb.Finalise" failed to execute and return error, transaction execution failed
3. The data set to Store (Keeper) will be rolled back, but the "storage" data and "code" data from CommitStateDB will remain in CommitStateDB.
4. Then, the problem encountered is Similar to issue667，issue668

[summerpro]

solution 1

• We can create a new snapshot of CommitStateDB before executing the handler. If the handler fails to execute and returns an error, then the Keeper.CommitStateDB will be rolled back to the old state.

// NewHandler returns a handler for Ethermint type messages.
func NewHandler(k Keeper) sdk.Handler {
	return func(ctx sdk.Context, msg sdk.Msg) (result *sdk.Result, err error) {
		snapshotStateDB := k.CommitStateDB.Copy()
		ctx = ctx.WithEventManager(sdk.NewEventManager())
		switch msg := msg.(type) {
		case types.MsgEthereumTx:
			result, err = handleMsgEthereumTx(ctx, k, msg)
		case types.MsgEthermint:
			result, err = handleMsgEthermint(ctx, k, msg)
		default:
			return nil, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "unrecognized %s message type: %T", ModuleName, msg)
		}
		if err != nil {
			types.CopyCommitStateDB(snapshotStateDB, k.CommitStateDB)
		}
		return result, err
	}
}