fix: cherry-pick 1515 to release/0.9: Error backfilling in case of same tx have multiples bridges

[joanestebanr]

cherry-pick from v0.8.x #1515

🔄 Changes Summary

• 💎 In case of filling a row that to_address is NULL is also updated
• 🐞backfill process is reading wrongly field DestinationAddress and OriginAddress of bridge table that produce an error extracting from_address, txn_sender and to_address

🛡️Security

• Bump github.com/ethereum/go-ethereum to fix vulnerability GO-2026-4511:

- Vulnerability #1: GO-2026-4511
    Go Ethereum Improperly Validates the ECIES Public Key in RLPx Handshake in
    github.com/ethereum/go-ethereum
  More info: https://pkg.go.dev/vuln/GO-2026-4511
  Module: github.com/ethereum/go-ethereum
    Found in: github.com/ethereum/go-ethereum@v1.16.7
    Fixed in: github.com/ethereum/go-ethereum@v1.16.9

• Closes bug: Fails to backfill some bridges in mainnet (v0.8.1) #1514

Adaptations

• Fix bridgesync/backfill_tx_sender_test.go that insert DestinationAddress and OriginAddress as string

[joanestebanr]

@claude

[claude]

Claude finished @joanestebanr's task in 1m 32s —— View job

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Code Review Complete ✅

Todo List

• Read changed files to understand the modifications
• Analyze backfill logic changes in backfill_tx_sender.go
• Review test changes in backfill_tx_sender_test.go
• Verify go-ethereum security update
• Check for potential bugs and security issues
• Assess code quality and best practices
• Provide structured feedback with priority levels

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🚀 What's New

This PR cherry-picks critical fixes from #1515 to the release/0.9 branch, addressing backfill process errors when reading bridge table fields and updating the to_address field. Additionally, it bumps go-ethereum to fix a security vulnerability.

🐛 Bug Fixes

• Fixed backfill process incorrectly reading DestinationAddress and OriginAddress fields from the bridge table (removed incorrect ,address meddler tags)
• Fixed backfill to update to_address field when it's NULL
• Fixed RecordUpdate struct to include ToAddr field for proper 3-field updates

📋 Config Updates

None

⚠️ Breaking Changes

None

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Review Feedback

🟢 Code Quality - Good Overall

The changes successfully address the stated issues. The core fixes are:

1. Meddler Tag Fix (bridgesync/backfill_tx_sender.go:127,129): Removed incorrect ,address tags from OriginAddress and DestinationAddress fields. These were causing the backfill process to read wrong data from the database.

2. Three-Field Update (bridgesync/backfill_tx_sender.go:142,321,340,348,384): Added ToAddr field to RecordUpdate struct and updated the bulk update SQL to handle to_address using COALESCE pattern, ensuring NULL values are filled.

3. Comprehensive Test Coverage (bridgesync/backfill_tx_sender_test.go): The test file has been significantly expanded with better edge case coverage, including tests for NULL handling, empty string handling, and various failure scenarios.

🔴 Security - go-ethereum Bump (REQUIRED)

✅ Properly Addressed: The PR correctly bumps github.com/ethereum/go-ethereum from v1.16.7 to v1.16.9 to fix vulnerability GO-2026-4511 (ECIES public key validation issue in RLPx handshake). This is a critical security fix.

🟡 Observations & Minor Suggestions

1. SQL UPDATE Pattern (bridgesync/backfill_tx_sender.go:382-384):

   UPDATE %s
   SET
       txn_sender = COALESCE(NULLIF(txn_sender, ''), ?),
       from_address = COALESCE(NULLIF(from_address, ''), ?),
       to_address = COALESCE(NULLIF(to_address, ''), ?)
   WHERE block_num = ? AND block_pos = ?;

   The COALESCE(NULLIF(field, ''), ?) pattern is clever - it only updates fields that are NULL or empty string, preserving existing non-empty values. This is the correct approach for backfilling missing data.

2. Test Quality Improvement: The test refactoring is excellent. New helper functions (newTestBridge, setup, insertBlock, insertBridge) make tests much more readable and maintainable. The comprehensive test cases in TestBackfillTxnSender_getRecordsNeedingBackfill_Cases thoroughly cover edge cases.

3. Meddler Tag Consistency: After the fix, OriginAddress and DestinationAddress now use the default meddler address codec (just meddler:"origin_address") instead of the explicit ,address tag. This is consistent with other address fields in the codebase like FromAddress and TxnSender.

🟢 Code Style & Best Practices

• ✅ Follows Go naming conventions
• ✅ Proper error wrapping with context
• ✅ Good use of testify require (not assert) as per CLAUDE.md guidelines
• ✅ Comprehensive test coverage including edge cases, context cancellation, and large batches
• ✅ Comments updated to reflect the new 3-field extraction

No Security Concerns Beyond the Fixed Vulnerability

The backfill logic properly handles:

• Context cancellation throughout the worker pool
• Transaction rollback on errors
• No SQL injection (uses parameterized queries)
• Proper resource cleanup with deferred closes

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Summary

This is a solid cherry-pick that addresses real bugs in the backfill process:

1. Root cause: The ,address meddler tags on OriginAddress and DestinationAddress were causing incorrect data extraction
2. Impact: Backfill process couldn't properly extract from_address, txn_sender, and to_address
3. Fix: Remove incorrect meddler tags + add ToAddr to the update flow + comprehensive tests

The security bump for go-ethereum is critical and properly implemented. The test improvements significantly enhance code reliability. I recommend approval for merge to release/0.9.

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
88.9% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud