Handle

eriksal1217

Vulnerability details

Impact

Gas Optimization - This finding does not affect the contract negatively nor does it put funds or transactions at risk for the user. Optimizes the contract to use less gas

Proof of Concept

According to the Slither Analyzer documentation (https://github.com/crytic/slither/wiki/Detector-Documentation#public-function-that-could-be-declared-external), public functions that are never called by the contract itself should be declared as external to save gas. This allows the contract to read directly from the call data. Allows for gas savings if you change a function from public to external, as in the external functions you do not have the extra logic to copy the data to memory.

Code snippet:

accrueSherX(IERC20) should be declared external:

function accrueSherX(IERC20 _token) public {...} <------ Should be declared as external

(contracts/libraries/LibSherX.sol, lines #75-81)

accrueSherXWatsons() should be declared external:

function accrueSherXWatsons() public {...} <------ Should be declared as external

(contracts/libraries/LibSherX.sol, lines #83-86)

Console output (Slither Analyzer):

getUnactivatedStakersPoolBalance(IERC20) should be declared external:

PoolBase.getUnactivatedStakersPoolBalance(IERC20) (contracts/facets/PoolBase.sol#146-148)

getTotalUnmintedSherX(IERC20) should be declared external:

PoolBase.getTotalUnmintedSherX(IERC20) (contracts/facets/PoolBase.sol#170-173)

accruedDebt(bytes32,IERC20) should be declared external:

LibPool.accruedDebt(bytes32,IERC20) (contracts/libraries/LibPool.sol#31-34)

getTotalAccruedDebt(IERC20) should be declared external:

LibPool.getTotalAccruedDebt(IERC20) (contracts/libraries/LibPool.sol#36-39)

accrueSherX(IERC20) should be declared external:

LibSherX.accrueSherX(IERC20) (contracts/libraries/LibSherX.sol#75-81)

accrueSherXWatsons() should be declared external:

LibSherX.accrueSherXWatsons() (contracts/libraries/LibSherX.sol#83-86)

deposit() should be declared external:

AaveV2.deposit() (contracts/strategies/AaveV2.sol#75-81)

Reference: https://github.com/crytic/slither/wiki/Detector-Documentation#public-function-that-could-be-declared-external

Tools Used

Sherlock Contracts Solidity (v 0.7.4) Slither Analyzer (v 0.8.0)

Recommended Mitigation Steps

Clone repository for Sherlock Smart Contracts
Create a python virtual environment with a stable python version
Install Slither Analyzer on the python VEM
Run Slither against all contracts

code-423n4 / 2021-07-sherlock-findings

[LibSherX.sol] Functions that should be declared as external to save gas #54