QuickSwap and StellaSwap contest - asutorufos's results

A concentrated liquidity DEX with dynamic fees.

General Information

Platform: Code4rena

Start Date: 26/09/2022

Pot Size: $50,000 USDC

Total HM: 13

Participants: 113

Period: 5 days

Judge: 0xean

Total Solo HM: 6

Id: 166

League: ETH

QuickSwap and StellaSwap

Findings Distribution

Researcher Performance

Rank: 61/113

Findings: 2

Award: $76.06

🌟 Selected for report: 0

🚀 Solo Findings: 0

External Links

Code4rena Contest Page Github Contest Repository Github Findings Repository QuickSwap and StellaSwap

Findings Information

🌟 Selected for report: 0xNazgul

Also found by: 0x1f8b, 0x52, 0xDecorativePineapple, 0xSmartContract, 0xmatt, Aeros, Aymen0909, Bnke0x0, Chom, CodingNameKiki, Deivitto, DimitarDimitrov, IllIllI, JC, Jeiwan, Lambda, Matin, Migue, Mukund, Ocean_Sky, Olivierdem, RaymondFam, RockingMiles, Rolezn, Ruhum, Satyam_Sharma, Shinchan, Tomo, Trabajo_de_mates, V_B, Waze, __141345__, a12jmx, ajtra, asutorufos, aysha, brgltd, bulej93, carrotsmuggler, catchup, cccz, chrisdior4, cryptonue, cryptphi, d3e4, defsec, delfin454000, durianSausage, erictee, fatherOfBlocks, gogo, kaden, karanctf, ladboy233, lukris02, mahdikarimi, martin, mics, natzuu, oyc_109, p_crypt0, pedr02b2, rbserver, reassor, rotcivegaf, rvierdiiev, sikorico, slowmoses, sorrynotsorry, tnevler, trustindistrust

Awards

52.0364 USDC - $52.04

Labels

bug

QA (Quality Assurance)

External Links

Link to GitHub issue

Low Risk Issues

Missing checks for address(0x0) when assigning values to address state variables. https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/DataStorageOperator.sol#L33 https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/AlgebraFactory.sol#L54-L55

Cases: 3

If updating >0.8.0 REQUIRE() SHOULD BE USED FOR CHECKING ERROR CONDITIONS ON INPUTS AND RETURN VALUES WHILE ASSERT() SHOULD BE USED FOR INVARIANT CHECKING https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/DataStorage.sol#L190 If updating remaining gas will not be refunded incase of failure.

Cases: 1

Non-critical issues

CONSTANTS SHOULD BE DEFINED RATHER THAN USING MAGIC NUMBERS https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/DataStorageOperator.sol#L138
Use a more recent version of solidity Most of the version is around 0.7.6. Since the version is not updated there could be multiple issues of things breaking. Having newer versions could let you use things that could be deprecated now. Or better practice.
REQUIRE()/REVERT() STATEMENTS SHOULD HAVE DESCRIPTIVE REASON STRINGS https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/PriceMovementMath.sol#L52-L53 https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/PriceMovementMath.sol#L70-71 https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/PriceMovementMath.sol#L87 https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/DataStorageOperator.sol#L43 https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/AlgebraPool.sol#L55

Cases: 6

Findings Information

🌟 Selected for report: IllIllI

Also found by: 0x1f8b, 0x5rings, 0xNazgul, 0xRoxas, 0xSmartContract, 0xbepresent, 0xmatt, Aeros, Amithuddar, Awesome, Aymen0909, B2, Bnke0x0, ChristianKuri, CodingNameKiki, Deivitto, Diraco, Fitraldys, HardlyCodeMan, JC, Mukund, Noah3o6, Olivierdem, RaymondFam, ReyAdmirado, RockingMiles, Rolezn, Ruhum, Saintcode_, Shinchan, SnowMan, TomJ, Tomio, Tomo, V_B, Waze, __141345__, ajtra, asutorufos, aysha, beardofginger, bobirichman, brgltd, bulej93, c3phas, ch0bu, cryptonue, defsec, delfin454000, dharma09, durianSausage, emrekocak, erictee, fatherOfBlocks, francoHacker, gianganhnguyen, gogo, imare, kaden, karanctf, ladboy233, lukris02, m_Rassska, martin, medikko, mics, natzuu, oyc_109, peiw, rbserver, ret2basic, rotcivegaf, saian, shark, slowmoses, tnevler, trustindistrust, zeesaw, zishansami

Awards

24.0179 USDC - $24.02

Labels

bug

G (Gas Optimization)

External Links

Link to GitHub issue

Gas Optimizations

Array length should not be looked up in every iteration. It waste gas to read the length in each iteration of a for loop even if it is a memory or calldata array. 3 gas per read https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/DataStorage.sol#L307

1 instance.

USE CALLDATA INSTEAD OF MEMORY When a function with a memory array is called externally, the abi.decode() step has to use a for-loop to copy each index of the calldata to the memory index. Each iteration of this for-loop costs at least 60 gas (i.e. 60 * <mem_array>.length). Using calldata directly bypasses this loop.

https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/DataStorageOperator.sol#L90 1 instance of this.

3 INCREMENTS/DECREMENTS CAN BE UNCHECKED IN FOR-LOOP Consider wrapping an unchecked block here (around 25 gas per instance) https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/DataStorage.sol#L307

1 instance of this.

Default initialization One doesn't have to put i= 0 as the default would be uint/int is 0. https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/DataStorage.sol#L307 1 instance of this.
SPLITTING REQUIRE() STATEMENTS THAT USE && SAVES GAS - (SAVES 8 GAS PER &&) Instead of using the && operator in a single require statement to check multiple conditions,using multiple require statements with 1 condition per require statement will save 8 GAS per && https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/DataStorageOperator.sol#L46

https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/AlgebraPool.sol#L739

https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/AlgebraPool.sol#L743

3 instances of this.

Comparisons: != is more efficient that > in require (6 gas less) This != 0 cost less than compared to > 0 for uint in require statements. For uints the minimum value would be 0 and never a negative value. Since it cannot be a negative value, then the check > 0 is essentially checking that the value is not equal to 0 therefore >0 can be replaced with !=0 which saves gas.

https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/PriceMovementMath.sol#L52-L53

https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/AlgebraPool.sol#L224

https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/AlgebraPool.sol#L434

https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/AlgebraPool.sol#L469

https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/AlgebraPool.sol#L641

6 instances of this