Long Revert Strings

[code423n4]

Handle

ye0lde

Vulnerability details

Impact

Shortening revert strings to fit in 32 bytes will decrease deployment time gas and will decrease runtime gas when the revert condition has been met.

Revert strings that are longer than 32 bytes require at least one additional mstore, along with additional overhead for computing memory offset, etc.

Proof of Concept

Revert strings > 32 bytes are here: https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/asset/AssetManager.sol#L44 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/asset/AssetManager.sol#L173 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/asset/AssetManager.sol#L236 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/asset/AssetManager.sol#L393 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/governance/UnionGovernor.sol#L143 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/MarketRegistry.sol#L25-L30 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/UToken.sol#L95-L100 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/UToken.sol#L116 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/UToken.sol#L398-L403 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/UToken.sol#L410 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/UToken.sol#L478-L480 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/UToken.sol#L625 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/UToken.sol#L685-L691 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/market/UToken.sol#L726 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/token/Comptroller.sol#L47 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/token/Comptroller.sol#L251 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/token/UnionToken.sol#L41 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/token/UnionToken.sol#L81 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/token/Whitelistable.sol#L21 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L70-L77 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L176 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L346 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L433 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L472 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L537-L549 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L621 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L659 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L705-L711 https://github.com/code-423n4/2021-10-union/blob/4176c366986e6d1a6b3f6ec0079ba547b040ac0f/contracts/user/UserManager.sol#L753

Tools Used

Visual Studio Code, Remix

Recommended Mitigation Steps

Shorten the revert strings to fit in 32 bytes.

[GalloDaSballo]

Agree with the finding, and appreciate the warden listing all occurrences

Personally would be happy with a no-fix as this is a one time payment to have a easy to understand error message on chain

That said, if the sponsor ever reaches gas limits, they know where to start cutting