USDT is not supported because of approval mechanism

[code423n4]

Lines of code

https://github.com/code-423n4/2022-12-tigris/blob/main/contracts/Trading.sol#L807

Vulnerability details

Impact

When using the approval mechanism in USDT, the approval must be set to 0 before it is updated.
https://etherscan.io/address/0xdac17f958d2ee523a2206206994597c13d831ec7#code

require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));

When _tigAsset is USDT, _handleCloseFees() should first approve(0) and then re-approve, in order to solve the problem that the user has operated before

Proof of Concept

        IStable(_tigAsset).mintFor(address(this), _daoFeesPaid);
        IStable(_tigAsset).approve(address(gov), type(uint).max);
        gov.distribute(_tigAsset, _daoFeesPaid);

Tools Used

vscode

Recommended Mitigation Steps

Set the allowance to 0 before setting it to the new value.

[c4-judge]

GalloDaSballo marked the issue as duplicate of #198

[c4-judge]

GalloDaSballo marked the issue as satisfactory