Missing events for functions that change critical parameters

[hats-bug-reporter[bot]]

Github username: @0xRizwan Twitter username: 0xRizwann Submission hash (on-chain): 0x8ca67b814b3209a78984b00f8ba821415be5e76137ea723fe528c41bf662bb71 Severity: low

Description: Description

The onlyOwner functions that change critical parameters should emit events.

1) Events allow capturing the changed parameters so that off-chain tools/interfaces can register such changes with timelocks that allow users to evaluate them and consider if they would like to engage/exit based on how they perceive the changes as affecting the trustworthiness of the protocol or profitability of the implemented financial services.

2) The alternative of directly querying on-chain contract state for such changes is not considered practical for most users/usages.

3) Missing events do not promote transparency and if such changes immediately affect users’ perception of fairness or trustworthiness, they could exit the protocol causing a reduction in liquidity which could negatively impact protocol TVL and reputation.

In GaugeUpgradeable.sol contrcats, below are owner functions that do not emit any events in the contracts.

    function setDistribution(address _distribution) external onlyOwner {
        require(_distribution != address(0), "zero addr");
        require(_distribution != DISTRIBUTION, "same addr");
        DISTRIBUTION = _distribution;
    }

    ///@notice set distribution address (should be GaugeProxyL2)
    function setMerklGaugeMiddleman(address _newMerklGaugeMiddleman) external onlyOwner {
        require(_newMerklGaugeMiddleman != address(0));
        merklGaugeMiddleman = _newMerklGaugeMiddleman;
    }

    ///@notice set distribution address (should be GaugeProxyL2)
    function setIsDistributeEmissionToMerkle(bool _isDistributeEmissionToMerkle) external onlyOwner {
        if (_isDistributeEmissionToMerkle) {
            require(merklGaugeMiddleman != address(0));
        }
        isDistributeEmissionToMerkle = _isDistributeEmissionToMerkle;
    }

    ///@notice set gauge rewarder address
    function setGaugeRewarder(address _gaugeRewarder) external onlyOwner {
        require(_gaugeRewarder != gaugeRewarder, "same addr");
        gaugeRewarder = _gaugeRewarder;
    }

    ///@notice set feeVault address
    function setFeeVault(address _feeVault) external onlyOwner {
        require(_feeVault != address(0), "zero addr");
        require(_feeVault != feeVault, "same addr");
        feeVault = _feeVault;
    }

    ///@notice set new internal bribe contract (where to send fees)
    function setInternalBribe(address _int) external onlyOwner {
        require(_int >= address(0), "zero");
        internal_bribe = _int;
    }

and GaugeFactoryUpgradeable.sol

    function setMerklGaugeMiddleman(address _newMerklGaugeMiddleman) external onlyOwner {
        merklGaugeMiddleman = _newMerklGaugeMiddleman;
    }

Recommendation

Add events to all onlyOwner functions that change critical parameters.

NOTE: Issue applicable to all such instances in inscope contracts