ConnectorRegistry Manual Review Findings

CRY-01M: Potential Failure of Graceful Function

Type	Severity	Location
Language Specific		ConnectorRegistry.sol:L132

Description:

The ConnectorRegistry::hasConnector function, in contrast to the ConnectorRegistry::connectorOf function, will gracefully handle the absence of a connector by yielding false instead of reverting.

A case exists whereby the function may inadvertently revert instead of yielding false; in case the customRegistries implementation satisfies the ICustomConnectorRegistry::connectorOf function selector but does not yield an argument, the overall transaction will revert due to an uncaught decoding error.

Impact:

The ConnectorRegistry::hasConnector function may ultimately revert even though its implementation approach indicates that it should not.

Example:

Copy
124function hasConnector(address target) external view returns (bool) {
125    if (connectors_[target] != address(0)) {
126        return true;
127    }
128
129    uint256 length = customRegistries.length;
130    for (uint256 i; i != length;) {
131        if (address(customRegistries[i]) != address(0)) {
132            try customRegistries[i].connectorOf(target) returns (
133                address _connector
134            ) {
135                if (_connector != address(0)) {
136                    return true;
137                }
138            } catch {
139                // Ignore
140            }
141
142            unchecked {
143                ++i;
144            }
145        }
146    }
147
148    return false;
149}

Recommendation:

We advise the system to either acknowledge this risk or perform a safer call to the ICustomConnectorRegistry::connectorOf function by evaluating whether the returned payload is 32 bytes in length and thus permits the decoding of the associated address argument.

Alleviation (6ab7af3bb495b817ffec469255ea679b1813eecb):

The code was updated per the latter of our two recommendations, introducing a low-level staticcall whose result is manually handled by evaluating whether the call is successful and the yielded payload is 32 bytes in length. As such, we consider this exhibit fully alleviated.