Long Revert Strings

[code423n4]

Handle

ye0lde

Vulnerability details

Impact

Shortening revert strings to fit in 32 bytes will decrease deploy 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-ambire/blob/bc01af4df3f70d1629c4e22a72c19e6a814db70d/contracts/libs/SignatureValidatorV2.sol#L33 https://github.com/code-423n4/2021-10-ambire/blob/bc01af4df3f70d1629c4e22a72c19e6a814db70d/contracts/libs/SignatureValidatorV2.sol#L55 https://github.com/code-423n4/2021-10-ambire/blob/bc01af4df3f70d1629c4e22a72c19e6a814db70d/contracts/libs/SignatureValidatorV2.sol#L59 https://github.com/code-423n4/2021-10-ambire/blob/bc01af4df3f70d1629c4e22a72c19e6a814db70d/contracts/libs/SignatureValidatorV2.sol#L64 https://github.com/code-423n4/2021-10-ambire/blob/bc01af4df3f70d1629c4e22a72c19e6a814db70d/contracts/libs/SignatureValidatorV2.sol#L65

Tools Used

Visual Studio Code, Remix

Recommended Mitigation Steps

Shorten the revert strings to fit in 32 bytes.

[Ivshti]

resolved in https://github.com/AmbireTech/adex-protocol-eth/commit/4e7c214a360ee4b685424e90d9c881c2b87cb373

[GalloDaSballo]

Agree with the finding, brownie handles this via // dev comments, not sure if hardhat provides a similar alternative (that costs 0)

[GalloDaSballo]

The sponsor has applied the improvement by using shorter strings