avaxAssignedHighWater is set wrongly in MinipoolManager.sol

[code423n4]

Lines of code

https://github.com/code-423n4/2022-12-gogopool/blob/aec9928d8bdce8a5a4efe45f54c39d4fc7313731/contracts/contract/MinipoolManager.sol#L373-L375

Vulnerability details

Impact

Detailed description of the impact of this finding.
avaxAssignedHighWater is set wrongly in MinipoolManager.sol at L373, particularly when the minipool was created via recreateMinipool().

Proof of Concept

Provide direct links to all referenced code in GitHub. Add screenshots, logs, or any other relevant proof that illustrates the concept.
According to the documentation of avaxAssignedHighWater at L26 of Staking.sol， ”staker.item.avaxAssignedHighWater = Highest amt of liquid staker funds assigned during a GGP rewards cycle“.
However, avaxAssignedHighWater is set wrongly in MinipoolManager.sol at L373 below:

if (staking.getAVAXAssignedHighWater(owner) < staking.getAVAXAssigned(owner)) {
			staking.increaseAVAXAssignedHighWater(owner, avaxLiquidStakerAmt);
}

It is wrong because instead of replacing the avaxAssignedHighWater with a larger value of avaxAssigned, it adds avaxLiquidStakerAmt on top of the existing avaxAssignedHighWater , which is inconsistent with the definition.
In particular, when this minipool was created via recreateMinipool(), the new avaxLiquidStakerAmt is a compound value which contains the original avaxLiquidStakerAmt ALREADY. The original avaxLiquidStakerAmt will be added AGAIN in this case, which is wrong. Therefore, the safest way is to assign the larger avaxAssigned, based on the definition to be 100% correct.

Tools Used

Remix

Recommended Mitigation Steps

We can fix it with the following code, which will replace the existing avaxAssignedHighWater with the current larger value of avaxAssigned using function resetAVAXAssignedHighWater.

if (staking.getAVAXAssignedHighWater(owner) < staking.getAVAXAssigned(owner)) {
			staking.resetAVAXAssignedHighWater(owner);
}

[c4-judge]

GalloDaSballo marked the issue as duplicate of #566

[c4-judge]

GalloDaSballo marked the issue as satisfactory