QuantAMM

Summary

The condition for updating the intermediateGradientStates mapping in the QuantAMMGradientBasedRule::_setGradient function is incorrect, leading to unintended behavior in subsequent calls.

Vulnerability Details

In the QuantAMMGradientBasedRule::_setGradient function, the logic to update the intermediateGradientStates[poolAddress] array relies on the condition:

QuantAMMGradientBasedRule::_setGradient function:

This condition is problematic because the length of the intermediateGradientStates[poolAddress] array after updating is calculated as .
For example:

• If _initialValues.length == 8, the resulting intermediateGradientStates[poolAddress].length will be 4.

• When _setGradient is called again, the condition _initialValues.length == storeLength (i.e., _initialValues.length == 4) is expected to pass. However, this condition fails because _initialValues.length should remain consistent with the original number of assets (_numberOfAssets) rather than shrinking after each update.

Impact

This incorrect condition results in the inability to correctly set new gradient values in subsequent calls.

Recommendations

Update the condition to ensure that it verifies the relationship between _initialValues.length and storeLength correctly.