[klauspost]

Enable disabled length check on SnappyConverter.Convert that could result in out-of-bounds reads buffer reads - or in case or re-use return values from the previous run.

Reported by @mfazrinizar

Summary by CodeRabbit

• Bug Fixes

  • Improved handling of malformed Snappy data with invalid literal lengths.
  • Corrupt compressed blocks are now rejected reliably instead of potentially reading leftover data.

• Tests

  • Added regression coverage for malformed blocks that declare more data than is available.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 7dc8f856-c356-452f-a607-5875178f4aee

📥 Commits

Reviewing files that changed from the base of the PR and between e29d4d3 and 837c4da.

📒 Files selected for processing (2)

• zstd/snappy.go
• zstd/snappy_test.go

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📝 Walkthrough

Walkthrough

Snappy literal decoding now validates that declared literal data fits within the remaining input. A regression test verifies malformed blocks return ErrSnappyCorrupt when a shared converter could otherwise encounter stale buffer data.

Changes

Snappy literal validation

Layer / File(s)	Summary
Validate literal bounds and malformed-block handling zstd/snappy.go, zstd/snappy_test.go	decodeSnappy rejects literal lengths exceeding the remaining input, and TestSnappy_ConvertMalformedLiteralStale verifies the converter returns ErrSnappyCorrupt for malformed blocks.

Estimated code review effort: 2 (Simple) | ~10 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly matches the main change: adding validation around SnappyConverter literal handling.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch prevent-oob-reads

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