ElasticSwap contest - OriDabush's results

Handle

OriDabush

Vulnerability details

Exchange.sol (removeLiquidity())

In Exchange.sol, in the removeLiquidity() function, you can use unchecked in order to save the gas wasting on overflow checks (you did the needed checks before).

New code suggestion:

unchecked {
    if (quoteTokenQtyToReturn > internalBalances.quoteTokenReserveQty) {
        internalBalances.quoteTokenReserveQty = 0;
    } else {
        internalBalances.quoteTokenReserveQty -= quoteTokenQtyToReturn;
    }
}

Handle

OriDabush

Vulnerability details

Mathlib.sol (calculateAddQuoteTokenLiquidityQuantities())

In the calculateAddQuoteTokenLiquidityQuantities() function, the return line is unnecessary, because those variables are returned anyway (it will save gas if you'll remove the return line.)

return (quoteTokenQty, liquidityTokenQty); // remove this line to save gas

Handle

OriDabush

Vulnerability details

Exchange.sol (isNotExpired())

The function isNotExpired() in the Exchange contract can be inlined in order to save the gas wasted on the function call. You can just use the calculation inside the function instead of calling the function, this will save the gas wasting on the function call.

Handle

OriDabush

Vulnerability details

Exchange.sol (removeLiquidity())

In the removeLiquidity() function in the Exchange contract, you can call totalSupply() once instead of calculating it twice (to save the gas wasting on the second function call).

old code:

    require(this.totalSupply() > 0, "Exchange: INSUFFICIENT_LIQUIDITY");
    // ...
    uint256 totalSupplyOfLiquidityTokens = this.totalSupply();

new code:

    uint256 totalSupplyOfLiquidityTokens = this.totalSupply();
    require(totalSupplyOfLiquidityTokens > 0, "Exchange: INSUFFICIENT_LIQUIDITY");
    // ...