Platform: Code4rena
Start Date: 10/02/2022
Pot Size: $30,000 USDC
Total HM: 5
Participants: 24
Period: 3 days
Judge: harleythedog
Total Solo HM: 3
Id: 86
League: ETH
Rank: 20/24
Findings: 1
Award: $90.00
🌟 Selected for report: 0
🚀 Solo Findings: 0
🌟 Selected for report: pauliax
Also found by: 0x1f8b, Dravee, GreyArt, Omik, ShippooorDAO, Tomio, bobi, cmichel, csanuragjain, defsec, gzeon, kenta, kenzo, m_smirnova2020, rfa, robee, sirhashalot, ye0lde
90.0012 USDC - $90.00
The functions use prefix increaments (i ++) instead of postfix increaments (++ i). Prefix increaments are cheaper than postfix increaments.
https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/OperatorResolver.sol#L40 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/OperatorResolver.sol#L60 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/OperatorResolver.sol#L75 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L103 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L113 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L213 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L273 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L291 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L327 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L369 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L581 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedRecords.sol#L196 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L126 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L148 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L165 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L261 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L280 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L318 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/abstracts/MixinOperatorResolver.sol#L36 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/abstracts/MixinOperatorResolver.sol#L55
for (uint256 i = 0; i < namesLength; i++) {
Manual analysis
Change all prefix increaments to postfix increaments where it doesn't affects the functionality.
For loop indices across the contract functions use explicit 0 initializations which are not required because the default value of uints is 0. Removing this explicit unnecessary initialization will save a little gas.
https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/OperatorResolver.sol#L40 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/OperatorResolver.sol#L60 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/OperatorResolver.sol#L75 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L103 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L113 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L153 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L213 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L273 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L291 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L327 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L369 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedRecords.sol#L196 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L318
for (uint256 i = 0; i < namesLength; i++) {
Remix
Remove unnecessary initialization of loop index variable
Reading array length at each iteration of the loop takes 6 gas (3 for mload and 3 to place memory_offset) in the stack. Caching the array length in the stack saves around 3 gas per iteration.
https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L261 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/FeeSplitter.sol#L318
function findShareholder(address _account) external view returns (uint256) { for (uint256 i = 0; i < shareholders.length; i++) { if (shareholders[i].account == _account) return i; } revert("FS: SHAREHOLDER_NOT_FOUND"); }
Manual
Caching len = shareholders.length and using the len instead will save gas.
For the arithmetic operations that will never over/underflow, using the unchecked directive (Solidity v0.8 has default overflow/underflow checks) can save some gas from the unnecessary internal over/underflow checks.
Manual analysis
Consider using 'unchecked' where it is safe to do so.
Where possible, use equivalent function parameters or local variables in event emits instead of state variables to prevent expensive SLOADs. Post-Berlin, SLOADs on state variables accessed first-time in a transaction increased from 800 gas to 2100, which is a 2.5x increase.
function setMaxHoldingsCount(uint256 _maxHoldingsCount) external onlyOwner { require(_maxHoldingsCount != 0, "NRC: INVALID_MAX_HOLDINGS"); maxHoldingsCount = _maxHoldingsCount; emit MaxHoldingsChanges(maxHoldingsCount); }
Manual analysis
Revert strings that are longer than 32 bytes require at least one additional mstore, along with additional overhead for computing memory offset, etc.
https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/NestedFactory.sol#L444 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/operators/ZeroEx/ZeroExOperator.sol#L36 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/operators/ZeroEx/ZeroExOperator.sol#L37 https://github.com/code-423n4/2022-02-nested/blob/fe6f9ef7783c3c84798c8ab5fc58085a55cebcfc/contracts/abstracts/OwnableProxyDelegation.sol#L56
require(amounts[1] <= _amountToSpend, "NestedFactory::_safeSubmitOrder: Overspent");
Manual analysis
Shorten the revert strings to fit in 32 bytes.
#0 - adrien-supizet
2022-02-15T11:34:25Z
1, 2, 3, 4 -> disputed, already acknowledged during the first audit 5 -> disputed, after applying the change, I see no difference 6 -> confirmed
#1 - harleythedogC4
2022-03-13T04:09:37Z
My personal judgments:
#2 - harleythedogC4
2022-03-13T06:17:05Z
Now, here is the methodology I used for calculating a score for each gas report. I first assigned each submission to be either small-optimization (1 point), medium-optimization (5 points) or large-optimization (10 points), depending on how useful the optimization is. The score of a gas report is the sum of these points, divided by the maximum number of points achieved by a gas report. This maximum number was 10 points, achieved by #67.
The number of points achieved by this report is 2 points. Thus the final score of this gas report is (2/10)*100 = 20.