Liquidity Management

GmxProxy.sol

Observation:
In both createOrder and settle, the execution fee is computed as the product of the estimated gas limit (obtained via getExecutionGasLimit) and tx.gasprice. Under EIP‑1559 and in volatile gas price environments, tx.gasprice can be manipulated or may not accurately reflect the actual fee dynamics (e.g. base fee versus priority fee).

Issue Path:
Relying solely on tx.gasprice may cause significant miscalculations in the required execution fee. If the fee is undercharged, the protocol might later encounter insufficient funds to cover the order’s execution; if overcharged, it may result in excess funds being locked or unnecessarily refunded. Over many orders, such discrepancies can erode fairness and may even be exploited if an attacker can influence gas price dynamics around order creation.

Recommendation:
Incorporate a fee calculation method that accounts for the EIP‑1559 fee mechanism—differentiating between base fee and priority fee—or use an on‑chain oracle for gas price reference. This would ensure that the calculated execution fee more accurately reflects the cost of execution under current network conditions.