First Flight #8: Math Master

Summary

Use of OR in MathMasters::mulWadUp overflow check results in overflow.

Vulnerability Details

The function checks for potential overflow in the context of fixed-point arithmetic by using the OR operator. However, the OR operator itself can cause an overflow. In this case, the first condition checks if y is non-zero and if x is greater than the maximum value divided by y. The second condition checks if x is non-zero.

Impact

In situations where x is 2 and y is 5.789e76, an overflow will occur.

Tools Used

Foundry:: Forge::Fuzz Test

Recommendations

Use a different method to check for potential overflow or do not check for x being non-zero. The equivalent function in solady, for example, does not check if x is non-zero in its overflow check.