Rich Smoke Cheetah - Lack of incentives to call bumpEarningPower for small rewards

[sherlock-admin3]

Rich Smoke Cheetah

Medium

Lack of incentives to call bumpEarningPower for small rewards

Summary

Since the tip that will be received in the bumpEarningPower function must be less or equal to the minimum between the unclaimed fees and the maxBumpTip, if the rewards are too small, there is a lack of incentives to call this function.

Vulnerability Detail

Here we can see that the tip that will be received in the bumpEarningPower must be less or equal to the minimum between the unclaimed fees and the maxBumpTip in the bumpEarningPower function.

    uint256 _unclaimedRewards = deposit.scaledUnclaimedRewardCheckpoint / SCALE_FACTOR;

    (uint256 _newEarningPower, bool _isQualifiedForBump) = earningPowerCalculator.getNewEarningPower(
      deposit.balance, deposit.owner, deposit.delegatee, deposit.earningPower
    );
    if (!_isQualifiedForBump || _newEarningPower == deposit.earningPower) {
      revert GovernanceStaker__Unqualified(_newEarningPower);
    }

    if (_newEarningPower > deposit.earningPower && _unclaimedRewards < _requestedTip) {
      revert GovernanceStaker__InsufficientUnclaimedRewards();
    }

    // Note: underflow causes a revert if the requested  tip is more than unclaimed rewards
    if (_newEarningPower < deposit.earningPower && (_unclaimedRewards - _requestedTip) < maxBumpTip)
    {
      revert GovernanceStaker__InsufficientUnclaimedRewards();
    }

Otherwise, the call will revert because of an underflow or a custom error. But if the reward is very small, then there is a clear lack of incentives to call this function.

Impact

Some deposits’ earning power will not be updated by bumpers, which can lead to problems in the protocol’s accounting.

Code Snippet

https://github.com/sherlock-audit/2024-11-tally/blob/main/staker/src/GovernanceStaker.sol#L483-L500

Tool used

Manual Review

Recommendation

In order to mitigate this issue, the protocol should implement a function that batches the protocol IDs in order to bump the earning power of many deposits at the same time and share the tip paid proportionally.