Fee Calculation Rounding Down Reduces Protocol Revenue in `UpliftOnlyExample`
Summary
The UpliftOnlyExample contract uses a rounding method in the fee calculation that may result in slightly reduced fee collection for the protocol. The use of mulDown in calculating fees rounds down the result, potentially leading to a small loss in revenue over time.
Vulnerability Details
The mulDown function rounds the result down to the nearest integer, discarding any fractional part of the fee. This rounding method can lead to the protocol collecting slightly less in fees than it would if the calculation were exact.
Impact
Over numerous transactions, the rounding down can accumulate to a non-trivial amount of lost fees, especially if the fee percentage is small and transaction volumes are high.
Tools Used
Manual Review
Recommendations
Consider the use of mulUp to capture fractional fees and maximize fee revenue.
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Informational or Gas / Admin is trusted / Pool creation is trusted / User mistake / Suppositions
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