Inverse Finance contest - Rahoz's results

L. Market allow IOA not in BorrowController.contractAllowlist to deposit

When a IOA not allow to borrow, it still can deposit but can't do anything So they have to call withdraw. Consider to block deposit from IOA which not in BorrowController.contractAllowlist

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L258-L260

Recommended Mitigation Steps

Should block deposit from unallowed IOA to Market

L. Missing Sanity Checks

There are some functions that miss sanity checks on arguments

Proof of Concept

gov, lender, pauseGuardian, escrowImplementation https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L61 operator https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L29 dbr,dola,gov,chair,supplyCeiling https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L36 replenishmentPriceBps,name,symbol,operator https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L30 operator https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L13 token,beneficiary https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/GovTokenEscrow.sol#L30 xINV https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L34 token,beneficiary https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L44 token https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/SimpleERC20Escrow.sol#L25

Recommended Mitigation Steps

Should add sanity check

N. SHOULD ADD MODIFIER

In Fed contract we have some functions require only governance/chair role can call To make code more simplier to read and reduce duplicate code, we should add modifier

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L49 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L58 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L67 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L76 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L87 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L104

Recommended Mitigation Steps

modifier onlyGov {
    require(msg.sender == gov, "Only gov can call this function");
    _;
}
modifier onlyChair {
    require(msg.sender == chair, "Only chair can call this function");
    _;
}

N. SHOULD CHECK OLD VALUE MUST DIFFERENT WITH NEW

Should require new value must be diffent with current value

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L44 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L61 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L118 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L124 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L130 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L136 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L142 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L149 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L161 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L172 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L183 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L194 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L48 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L57 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L66 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L75 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L53 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L62 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L81 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L90 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L99 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L26 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L32 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L38

N. Code Duplicate

Oracle.getPrice and Oracle.viewPrice have some parts duplicated.

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L79-L89 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L93-L104

Recommended Mitigation Steps

Consider to create internal functions

N. FUNCTION ORDER

Functions should be ordered following the Solidity conventions. Link: https://docs.soliditylang.org/en/v0.8.15/style-guide.html#order-of-functions

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/main/src/Market.sol https://github.com/code-423n4/2022-10-inverse/blob/main/src/Oracle.sol https://github.com/code-423n4/2022-10-inverse/blob/main/src/Fed.sol https://github.com/code-423n4/2022-10-inverse/blob/main/src/DBR.sol https://github.com/code-423n4/2022-10-inverse/blob/main/src/BorrowController.sol https://github.com/code-423n4/2022-10-inverse/blob/main/src/escrows/INVEscrow.sol

N. Missing event emit

Should emit events after write functions to make tracking process better.

Proof of Concept

Market https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L118 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L124 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L130 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L136 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L142 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L149 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L161 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L172 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L183 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L194 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L203 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L212 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L520 Fed https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L48 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L57 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L66 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L75 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L131 DBR https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L53 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L62 BorrowController https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L26 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L32 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L38 Oracle https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L44 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L53 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L61 GovTokenEscrow https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/GovTokenEscrow.sol#L43 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/GovTokenEscrow.sol#L66 INVEscrow https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L59 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L79 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L90 SimpleERC20Escrow https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/SimpleERC20Escrow.sol#L36

Should check credit before update debts

If borrower credit is lower than new borrow amount + debts[borrower], it should be reverted before update the storage debts[borrower]

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L395-L396

Recommended Mitigation Steps

function borrowInternal(address borrower, address to, uint amount) internal {
    require(!borrowPaused, "Borrowing is paused");
    if(borrowController != IBorrowController(address(0))) {
        require(borrowController.borrowAllowed(msg.sender, borrower, amount), "Denied by borrow controller");
    }
    uint credit = getCreditLimitInternal(borrower);
    require(credit >= debts[borrower] + amount, "Exceeded credit limit");
		debts[borrower] += amount;
    totalDebt += amount;
    dbr.onBorrow(borrower, amount);
    dola.transfer(to, amount);
    emit Borrow(borrower, amount);
}

Can use internal function instead of public

Market.depositAndBorrow and Market.repayAndWithdraw do call public function inside, it can save gas by call the internal functions of each.

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L267-L270 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L546-L549

Recommended Mitigation Steps

Call internal function to save JUMP step

function depositAndBorrow(uint amountDeposit, uint amountBorrow) public {
    deposit(msg.sender, amountDeposit);
		borrowInternal(msg.sender, msg.sender, amountBorrow);
}
function repayAndWithdraw(uint repayAmount, uint withdrawAmount) public {
    repay(msg.sender, repayAmount);
    withdrawInternal(msg.sender, msg.sender, withdrawAmount);
}

Return should go before query debt

DBR.accrueDueTokens do accrue due DBR of user, if same block.timestamp then do nothing. So we can check valid time first, then query debt of user.

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L285

Recommended Mitigation Steps

Should return first, if not return then we can query debt

function accrueDueTokens(address user) public {
    if(lastUpdated[user] == block.timestamp) return;
		uint debt = debts[user];
    uint accrued = (block.timestamp - lastUpdated[user]) * debt / 365 days;
    dueTokensAccrued[user] += accrued;
    totalDueTokensAccrued += accrued;
    lastUpdated[user] = block.timestamp;
    emit Transfer(user, address(0), accrued);
}

Functions Visibility

There are public functions that can be external for consistency and gas saving

Proof of Concept

Market https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L118 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L578 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L124 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L130 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L136 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L142 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L149 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L172 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L183 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L194 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L203 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L212 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L267 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L370 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L422 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L486 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L520 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L546 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L591 Oracle https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L44 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L53 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L61 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L66 Fed https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L48 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L57 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L66 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L75 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L86 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L103 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L131 DBR https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L53 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L62 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L70 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L81 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L90 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L99 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L109 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L146 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L158 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L170 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L188 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L215 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L258 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L300 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L313 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L325 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L340 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L349 BorrowController https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L26 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L32 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L38 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L46 GovTokenEscrow https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/GovTokenEscrow.sol#L30 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/GovTokenEscrow.sol#L43 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/GovTokenEscrow.sol#L52 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/GovTokenEscrow.sol#L66 INVEscrow https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L44 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L59 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L70 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L79 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/INVEscrow.sol#L90 SimpleERC20Escrow https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/SimpleERC20Escrow.sol#L25 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/SimpleERC20Escrow.sol#L36 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/escrows/SimpleERC20Escrow.sol#L45

Don’t compare boolean expressions to boolean literals

We dont need to compare boolean expressions to boolean literals

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L89 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L350

Add unchecked {} for subtractions where the operands cannot underflow because of a previous

Since we already check it cannot underflow, we can use unchecked for save gas

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L362 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L379 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L534-L535 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L110-L111 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L124 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L111 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L124 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L137 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L172 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L196 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L374

USE ASSEMBLY FOR SIMPLE SETTERS

Where it does not affect readability, using assembly allows to save gas not only on deployment, but also on function calls.

Proof of Concept

https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L44 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L53 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Oracle.sol#L61 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L118 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L124 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L130 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L136 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L142 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L149 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L161 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L172 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L183 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Market.sol#L194 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L48 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L57 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L66 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/Fed.sol#L75 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L53 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L62 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L81 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L90 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/DBR.sol#L99 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L26 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L32 https://github.com/code-423n4/2022-10-inverse/blob/3e81f0f5908ea99b36e6ab72f13488bbfe622183/src/BorrowController.sol#L38

Recommended Mitigation Steps

This is the case for instance for simple Pending Operator setters. Oracle

function setPendingOperator(address newOperator_) public onlyOperator { 
	assembly {
    sstore(pendingOperator.slot, newOperator_)
  }
}