Golom contest - luckypanda's results

There are redundant lines of codes in validateOrder. In line 177, there is a require(signaturesigner == o.signer, 'invalid signature'); where it will throw an error if signaturesigner is not equal to o.signer and following that there is an if condition where if signaturesigner is not equal to o.signer it will return something. This lines of codes won't be called because when signaturesigner != o.signer it will throw an error in require and won't reach the if condition.

https://github.com/code-423n4/2022-07-golom/blob/e5efa8f9d6dda92a90b8b2c4902320acf0c26816/contracts/core/GolomTrader.sol#L177-L180

        require(signaturesigner == o.signer, 'invalid signature');
        if (signaturesigner != o.signer) {
            return (0, hashStruct, 0);
        }

Solution:

• Delete the if conditional part because it's redundant. The validateOrder will looks like this:

   function validateOrder(Order calldata o)
        public
        view
        returns (
            uint256,
            bytes32,
            uint256
        )
    {
        // match signature
        bytes32 hashStruct = _hashOrder(o);
        bytes32 hash = keccak256(abi.encodePacked('\x19\x01', EIP712_DOMAIN_TYPEHASH, hashStruct));
        address signaturesigner = ecrecover(hash, o.v, o.r, o.s);
        require(signaturesigner == o.signer, 'invalid signature');
        if (signaturesigner != o.signer) {
            return (0, hashStruct, 0);
        }
        //deadline
        if (block.timestamp > o.deadline) {
            return (1, hashStruct, 0);
        }
        // not cancelled by nonce or by hash
        if (o.nonce != nonces[o.signer]) {
            return (2, hashStruct, 0);
        }
        if (filled[hashStruct] >= o.tokenAmt) {
            // handles erc1155
            return (2, hashStruct, 0);
        }
        return (3, hashStruct, o.tokenAmt - filled[hashStruct]);
    }