L2Sender reinit fix

[maurelian]

Description

Fixes an issue which would allow for a single messages to be replayed twice by intercepting an upgrade.

This is addressed in two ways:

• Do not over the xDomainMsgSender if it is not the default value.
• Added another check that successfulMessages for the message is still false after the
  external call.

Exploit Description

To perform the exploit, the following steps must be taken by the attacker:

1. Wait for a signed upgrade transaction.
2. Once the signed upgrade transaction is available, front-run by running it inside a
   withdrawal transaction.
3. The attacker's withdrawal payload will call their own contract which would run the
   upgrade transaction and then re-enter relayMessage() with their own same
   withdrawal message.
4. The reentrancy will succeed since xDomainMsgSender has been reset by the upgrade.

The attacker must also satisfy the following with their withdrawal message:

1. It must be a failed withdrawal so they can re-enter relayMessage(). A fresh withdrawal
   cannot reenter as it checks failedMessages[versionedHash] is true.
2. It must have a value set. The amount for value is the amount that they will able to
   drain from the contract.

[semgrep-app]

Semgrep found 1 writable-filesystem-service finding:

• indexer/docker-compose.yml: L120

Service 'backend-goerli' is running with a writable root filesystem. This may allow malicious applications to download and run additional payloads, or modify container files. If an application inside a container has to save something temporarily consider using a tmpfs. Add 'read_only: true' to this service to prevent this.

_{Ignore this finding from writable-filesystem-service.}

Semgrep found 1 no-new-privileges finding:

• indexer/docker-compose.yml: L120

Service 'backend-goerli' allows for privilege escalation via setuid or setgid binaries. Add 'no-new-privileges:true' in 'security_opt' to prevent this.

_{Ignore this finding from no-new-privileges.}

[codecov]

Codecov Report

Attention: 5 lines in your changes are missing coverage. Please review.

Comparison is base (8b197bc) 34.52% compared to head (3f9d045) 25.67%.
Report is 95 commits behind head on develop.

❗ Current head 3f9d045 differs from pull request most recent head f80e4b9. Consider uploading reports for the commit f80e4b9 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #8797      +/-   ##
===========================================
- Coverage    34.52%   25.67%   -8.86%     
===========================================
  Files          167      119      -48     
  Lines         7171     4892    -2279     
  Branches      1214     1066     -148     
===========================================
- Hits          2476     1256    -1220     
+ Misses        4545     3530    -1015     
+ Partials       150      106      -44     

Flag	Coverage Δ
cannon-go-tests	?
chain-mon-tests	27.14% <ø> (ø)
common-ts-tests	?
contracts-bedrock-tests	20.20% <0.00%> (+0.11%)	⬆️
contracts-ts-tests	12.25% <ø> (ø)
core-utils-tests	?
sdk-next-tests	42.18% <ø> (ø)
sdk-tests	42.18% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...ontracts-bedrock/src/L1/L1CrossDomainMessenger.sol	0.00% <ø> (ø)
...ontracts-bedrock/src/L2/L2CrossDomainMessenger.sol	0.00% <ø> (ø)
...ckages/contracts-bedrock/src/L1/OptimismPortal.sol	0.00% <0.00%> (ø)
...cts-bedrock/src/universal/CrossDomainMessenger.sol	0.00% <0.00%> (ø)

... and 51 files with indirect coverage changes

[tynes]

Do we also need the same fix in the optimism portal?

[maurelian]

Do we also need the same fix in the optimism portal?

It's not critical, because we write the withdraw to the mapping before sending, but we should make the fix anyways.

optimism/packages/contracts-bedrock/src/L1/OptimismPortal.sol

Lines 319 to 320 in 18097d2

	// Mark the withdrawal as finalized so it can't be replayed.
	finalizedWithdrawals[withdrawalHash] = true;

I will add that to this PR.

[semgrep-app]

Semgrep found 7 sol-style-notice-over-dev-natspec findings:

• packages/contracts-bedrock/src/dispute/interfaces/IOutputBisectionGame.sol: L57, L38, L12
• packages/contracts-bedrock/src/dispute/interfaces/IBondManager.sol: L48, L41, L36, L28

Prefer @notice over @dev in natspec comments

_{Ignore this finding from sol-style-notice-over-dev-natspec.}

Semgrep found 1 no-printf-in-responsewriter finding:

• op-exporter/main.go: L83

Detected 'printf' or similar in 'http.ResponseWriter.write()'. This bypasses HTML escaping that prevents cross-site scripting vulnerabilities. Instead, use the 'html/template' package to render data to users.

_{Ignore this finding from no-printf-in-responsewriter.}

Semgrep found 1 no-direct-write-to-responsewriter finding:

• op-exporter/main.go: L83

Detected directly writing or similar in 'http.ResponseWriter.write()'. This bypasses HTML escaping that prevents cross-site scripting vulnerabilities. Instead, use the 'html/template' package and render data using 'template.Execute()'.

_{Ignore this finding from no-direct-write-to-responsewriter.}

Semgrep found 1 use-tls finding:

• op-exporter/main.go: L138

Found an HTTP server without TLS. Use 'http.ListenAndServeTLS' instead. See https://golang.org/pkg/net/http/#ListenAndServeTLS for more information.

_{Ignore this finding from use-tls.}

Semgrep found 1 context-todo finding:

• op-exporter/main.go: L156

Consider to use well-defined context

_{Ignore this finding from context-todo.}

Semgrep found 1 use-fprintf-not-write-fsprint finding:

• op-exporter/main.go: L83

use fmt.Fprintf(w, { "healthy": "%t", "version": "%s" }, health.healthy, *health.version) instead of fmt.Sprintf and []byte conversion

_{Ignore this finding from use-fprintf-not-write-fsprint.}

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Commits

Files that changed from the base of the PR and between 19c79fe and f80e4b9.

Walkthrough

The recent updates to the contracts involve incrementing semantic version constants, enhancing initialization checks, and adding reentrancy protection. The L1CrossDomainMessenger and L2CrossDomainMessenger contracts have their versions updated, reflecting new features or fixes. The OptimismPortal contract introduces a default sender initialization. The universal CrossDomainMessenger contract adds reentrancy guards. Test contracts are updated to include checks for reentrancy vulnerabilities during initialization and message relaying.

Changes

File Path	Change Summary
.../L1/L1CrossDomainMessenger.sol .../L2/L2CrossDomainMessenger.sol	Updated semantic version constants.
.../L1/OptimismPortal.sol	Version bumped from "2.3.0" to "2.4.0"; added default l2Sender initialization.
.../universal/CrossDomainMessenger.sol	Enhanced reentrancy protection and conditional xDomainMsgSender initialization.
.../test/L1/L1CrossDomainMessenger.t.sol	Added tests for reentrancy vulnerability.

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[semgrep-app]

Semgrep found 1 sol-style-notice-over-dev-natspec finding:

• packages/contracts-bedrock/src/dispute/interfaces/IFaultDisputeGame.sol: L12

Prefer @notice over @dev in natspec comments

_{Ignore this finding from sol-style-notice-over-dev-natspec.}