Liquidity Management

The function getPositionInfo() miscalculates the net value of a position due to incorrect handling of negative PnL (positionInfo.basePnlUsd). The flawed logic in the following snippet:

incorrectly casts negative PnL, potentially increasing the net value instead of reducing it. This happens because Solidity does not support negative numbers natively, and -positionInfo.basePnlUsd can wrap incorrectly when converted to an unsigned integer. As a result, traders with losses could appear to have more collateral than they actually do, preventing necessary liquidations. To add, the function does not cap net value to a safe upper limit, meaning that in cases where fees are not properly accounted for, positions may remain open despite being under-collateralized, leading to protocol insolvency.

Impact

Under-collateralized positions are incorrectly kept open, preventing necessary liquidations and exposing the protocol to potential bad debt accumulation.

Mitigation

Ensure proper subtraction of negative PnL by explicitly converting signed values before arithmetic operations and enforce an upper bound on net value to prevent manipulation.