Inconsistency in view functions can lead to users believing they’re due for more BKD rewards

[code423n4]

Lines of code

https://github.com/code-423n4/2022-05-backd/blob/2a5664d35cde5b036074edef3c1369b984d10010/protocol/contracts/tokenomics/AmmConvexGauge.sol#L107-L111
https://github.com/code-423n4/2022-05-backd/blob/2a5664d35cde5b036074edef3c1369b984d10010/protocol/contracts/tokenomics/AmmConvexGauge.sol#L129-L134

Vulnerability details

Impact

The view functions used for a user to check their claimable rewards vary in their implementation. This can cause users to believe they are due X amount but will receive Y.

Proof of Concept

If the inflationRecipient is set, then poolStakedIntegral will be incremented in claimableRewards() but not in any other function like allClaimableRewards() or poolCheckpoint().

If a user calls claimableRewards() after the inflationRepient has been set, claimableRewards() will return a larger value than allClaimableRewards() or the amount actually returned by claimRewards().

Tools Used

Manual review

Recommended Mitigation Steps

To make the logic consistent, claimableRewards() needs if (inflationRecipient == address(0)) added to it.

[GalloDaSballo]

The warden has identified an incorrect implementation in how rewards are shown, while no assets are at risk, the issue identified is a programming mistake that could cause further issues.

For this reason I agree with Medium Severity

[GalloDaSballo]

I'm still fairly conflicted on severity as the impact is going to be quite small, however at this time, because the "code is wrong", I still think Medium Severity to be valid