[L04] Prevent initialization of the Configurator implementation contr…

…act (#425)

This change should prevent anyone from being able to call initialize on the implementation contract of Configurator.

Addresses #378

contracts/Configurator.sol

@@ -42,6 +42,12 @@ contract Configurator is ConfiguratorStorage {
     error InvalidAddress();
     error Unauthorized();
 
+    /// @notice Constructs a new Configurator instance
+    constructor() {
+        // Set a high version to prevent the implementation contract from being initialized
+        version = type(uint256).max;
+    }
+
     /// @notice Initializes the storage for Configurator
     function initialize(address _governor, address _factory, Configuration calldata _config) public {
         if (version != 0) revert AlreadyInitialized();

test/configurator-test.ts

@@ -44,7 +44,7 @@ describe('configurator', function () {
 
     const configuratorAsProxy = configurator.attach(configuratorProxy.address);
     const txn = await wait(configuratorAsProxy.deploy()) as any;
-    const [ newCometAddress ] = txn.receipt.events.find(event => event.event === 'CometDeployed').args;
+    const [newCometAddress] = txn.receipt.events.find(event => event.event === 'CometDeployed').args;
 
     expect(event(txn, 0)).to.be.deep.equal({
       CometDeployed: {
@@ -104,6 +104,13 @@ describe('configurator', function () {
     await expect(configuratorAsProxy.initialize(governor.address, cometFactory.address, configuration)).to.be.revertedWith("custom error 'AlreadyInitialized()'");
   });
 
+  it('reverts if initializing the implementation contract', async () => {
+    const { governor, configurator, cometFactory } = await makeConfigurator();
+
+    let configuration = await configurator.getConfiguration();
+    await expect(configurator.initialize(governor.address, cometFactory.address, configuration)).to.be.revertedWith("custom error 'AlreadyInitialized()'");
+  });
+
   describe('configuration setters', function () {
     it('sets governor and deploys Comet with new configuration', async () => {
       const { configurator, configuratorProxy, proxyAdmin, comet, cometProxy, users: [alice] } = await makeConfigurator();