anya - Redundant Type Casting in calcUnrealisedDebt Function

[sherlock-admin]

anya

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Redundant Type Casting in calcUnrealisedDebt Function

Summary

The calcUnrealisedDebt function performs calculations using uint256 variables but declares its return type as uint128. While it casts the final result to uint128 using SafeCastLib.safeCastTo128, this conversion is unnecessary due to the function's declared return type. This redundancy creates an extra step and might potentially cause confusion.

Vulnerability Detail

• Redundant Type Casting: The function already specifies a return type of uint128, indicating its intention to return a value within that range. The additional call to SafeCastLib.safeCastTo128 serves no purpose as the compiler would automatically perform the required casting.
• Potential Confusion: The presence of the casting function might lead developers or readers to believe that the calculations internally use uint256 and require special handling for potential overflow.

Impact

• Reduced code clarity and readability.
• Slight impact on gas consumption due to the unnecessary function call.
• Potential misinterpretation of the function's behavior.

Code Snippet

https://github.com/sherlock-audit/2023-12-arcadia/blob/main/lending-v2/src/LendingPool.sol#L718-L736

Tool used

Manual Review

Recommendation

• Remove Unnecessary Casting: Eliminate the SafeCastLib.safeCastTo128 call as it's redundant and not required based on the declared return type.
• Set the return type to uint128

[sherlock-admin2]

1 comment(s) were left on this issue during the judging contest.

takarez commented:

invalid

[nevillehuang]

Invalid, design decision to cap to unrealisedDebt to uint128 so no issue here, safe cast is there as a safety check.