XDEFI contest - Fitraldys's results

Handle

Fitraldys

Vulnerability details

Impact

expensive gas, because in the line https://github.com/XDeFi-tech/xdefi-distribution/blob/v1.0.0-beta.0/contracts/XDEFIDistributionHelper.sol#L23, the tokenids.length is save to a new variable to be used in the for loop, instead of call tokenids.length directly in the for loop

Proof of Concept

pragma solidity =0.8.7;

contract pikir {

    function putar1 (uint256 [] memory tokenIds) external view returns(uint256) {
        
        uint256 alltokens = tokenIds.length;
        uint256 hasil;

        for (uint256 i; i < alltokens; ++i){
            
            hasil += 1;

        }
        return hasil;

    }

}
//24714 gas

contract pikir2 {

    function putar1 (uint256 [] memory tokenIds) external view returns(uint256) {
    
        uint256 hasil;

        for (uint256 i; i < tokenIds.length; ++i){
            
            hasil += 1;

        }
        return hasil;

    }

}
//24710 gas

Tools Used

remix