lockFor() in BkdLocker don't check that user is not 0x0 and if user by mistake call this function with value 0x0 s/he is going to lose his funds.

[code423n4]

Lines of code

https://github.com/code-423n4/2022-05-backd/blob/2a5664d35cde5b036074edef3c1369b984d10010/protocol/contracts/BkdLocker.sol#L227-L232

Vulnerability details

Impact

function lockFor() in BkdLocker is supposed to lock 'msg.senderfunds and increaseuseraddress funds but if anyone one calls it with0x0` address by mistake then his funds will be locked forever.

Proof of Concept

This is lockFor() code in BkdLocker:

    function lockFor(address user, uint256 amount) public override {
        govToken.safeTransferFrom(msg.sender, address(this), amount);
        _userCheckpoint(user, amount, balances[user] + amount);
        totalLocked += amount;
        emit Locked(user, amount);
    }

As you can see there is no check that user is not 0x0. code calls _userCheckpoint() which will increase 0x0 balances in the contract and there is no check in _userCheckpoint() either and user can lose all his funds just by one simple mistake.

Tools Used

VIM

Recommended Mitigation Steps

check that user is not 0x0 in lcokFor

[chase-manning]

Think this is more of a QA issue

[GalloDaSballo]

Per industry standard, non-zero checks are Low Severity, for this reason I will confirm the finding and downgrade to Low