XDZIBEC - XO-Incorrect type for rounding argument in scaleByBases function.

[sherlock-admin]

XDZIBEC

medium

XO-Incorrect type for rounding argument in scaleByBases function.

Summary

• The scaleByBases function expects the third argument to be a rounding mode. TheMathUpgradeable.Rounding type is an enum that represents the different rounding modes. The uint256 type can also be used to represent a rounding mode. The rounding argument in the scaleByBases function is of type MathUpgradeable.Rounding. However, the rounding argument should be of type uint256. This is because the mulDiv function expects the third argument to be a rounding mode. The uint256 type is compatible with the mulDiv function, and it can be used to represent a rounding mode.

  Vulnerability Detail

  /**
   * @notice Scale value by bases
   * @param sourceValue Value of the source to scale
   * @param sourceBase Base of the source, e.g., 1e18
   * @param targetBase Base of the target, e.g., 1e6
   * @param rounding Rounding mode that is `Up` or `Down`
   * @return Value of the target
   */
  function scaleByBases(
      uint256 sourceValue,
      uint256 sourceBase,
      uint256 targetBase,
      MathUpgradeable.Rounding rounding
  ) internal pure returns (uint256) {
      return sourceValue.mulDiv(targetBase, sourceBase, rounding);
  }
  }

• there is a vulnerability in thescaleByBases function, ThemulDiv function expects the first and third arguments to be the same type. the targetBase and sourceBase arguments are of type uint256, while the rounding argument is of type MathUpgradeable``.Rounding. This will cause a type error when the function is called. The correct type for the rounding argument is uint256. This is because the mulDiv function expects the third argument to be a rounding mode. The MathUpgradeable.Rounding type is an enum that represents the different rounding modes, the uint256 type can also be used to represent a rounding mode.

  Impact

• The vulnerability could cause the function to return incorrect results.

  Code Snippet

• https://github.com/sherlock-audit/2023-04-unitasprotocol/blob/main/Unitas-Protocol/src/utils/ScalingUtils.sol#L66C1-L82C2

  Tool used

Manual Review

Recommendation

• Change the type of the rounding argument to uint256, this will ensure that the mulDiv function can be called without any errors.