0xmuxyz - `safeApprove()` function deprecated is used in multiple lines

[sherlock-admin]

0xmuxyz

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safeApprove() function deprecated is used in multiple lines

Summary

• safeApprove() function deprecated is used in multiple lines.

Vulnerability Detail

• safeApprove() function has been deprecated by OpenZeppelin team: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2268
  • However, safeApprove() deprecated is still used in the multiple lines in this repo.

Impact

• Using this deprecated-function may lead to unexpected-behavior of smart contracts which this deprecated-function is used in the future.

Code Snippet

• safeApprove()function deprecated is used in the following lines in this repo:
  • https://github.com/sherlock-audit/2022-11-sense/blob/main/contracts/src/AutoRoller.sol#L132-L136
  • https://github.com/sherlock-audit/2022-11-sense/blob/main/contracts/src/AutoRoller.sol#L179-L180
  • https://github.com/sherlock-audit/2022-11-sense/blob/main/contracts/src/RollerPeriphery.sol#L101

Tool used

• Manual Review

Recommendation

• Instead of using safeApprove() function, safeIncreaseAllowance() function and safeDecreaseAllowance() function should be used. https://docs.openzeppelin.com/contracts/4.x/api/token/erc20#SafeERC20-safeApprove-contract-IERC20-address-uint256-