SimpleProxy Manual Review Findings

SPY-01M: Incorrect Implementation of Initialization

Type	Severity	Location
Logical Fault		SimpleProxy.sol:L25-L27

Description:

The SimpleProxy::constructor contains an invalid initialization methodology using delegatecall to self, resulting a "successful" call that does not initialize the contract.

Impact:

The flaw arises from the fact that when the constructor of the contract is being executed its code has not yet been stored on the blockchain. As such, a self-call of any kind (delegatecall / call / staticcall) will be performed to an address with no code thus succeeding while not executing any statement.

Example:

Copy
19/// @dev Initializes the proxy with an implementation specified by `_target`.
20/// @param _target Address of contract for proxy
21/// @param _initialCall Optional initial calldata
22constructor(address _target, bytes memory _initialCall) {
23  _setImplementation(_target);
24
25  if (_initialCall.length > 0) {
26    CallLib.delegateCallFunc(address(this), _initialCall);
27  }
28}

Recommendation:

We advise the code to perform a delegatecall instruction directly to the _target as otherwise the contract will not be initialized during deployment.

Alleviation (3dd3d7bf0c2693b2f9c23bacedfa420393f7ea84):

The contract now properly performs a delegatecall instruction to the intended _target of the proxy, initializing itself properly and alleviating this exhibit.