zstd: Fix back-referenced offset #793
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Since we expand backwards early, we may be in a situation where best.s+2 has already been indexed. This will result in picking up a 0 or negative offset, which leads to corrupted data. Skip this check if best.s is less than or equal to s-2. Regression from #784 (not released)
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Caught 15 minutes after this PR was opened on https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=57460 |
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This PR contains the following updates: | Package | Type | Update | Change | |---|---|---|---| | [github.com/klauspost/compress](https://togithub.com/klauspost/compress) | indirect | patch | `v1.16.3` -> `v1.16.5` | --- ### Release Notes <details> <summary>klauspost/compress</summary> ### [`v1.16.5`](https://togithub.com/klauspost/compress/releases/tag/v1.16.5) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.4...v1.16.5) #### What's Changed - zstd: readByte needs to use io.ReadFull by [@​jnoxon](https://togithub.com/jnoxon) in [klauspost/compress#802 - gzip: Fix WriterTo after initial read by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#804 #### New Contributors - [@​jnoxon](https://togithub.com/jnoxon) made their first contribution in [klauspost/compress#802 **Full Changelog**: klauspost/compress@v1.16.4...v1.16.5 ### [`v1.16.4`](https://togithub.com/klauspost/compress/releases/tag/v1.16.4) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.3...v1.16.4) #### What's Changed - s2: Fix huge block overflow by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#779 - s2: Allow CustomEncoder fallback by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#780 - zstd: Fix amd64 not always detecting corrupt data by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#785 - zstd: Improve zstd best efficiency by [@​klauspost](https://togithub.com/klauspost) and [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#784 - zstd: Make load(32|64)32 safer and smaller by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#788 - zstd: Fix quick reject on long backmatches by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#787 - zstd: Revert table size change by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#789 - zstd: Respect WithAllLitEntropyCompression by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#792 - zstd: Fix back-referenced offset by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#793 - zstd: Load source value at start of loop by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#794 - zstd: Shorten checksum code by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#795 - zstd: Fix fallback on incompressible block by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#798 - gzhttp: Suppport ResponseWriter Unwrap() in gzhttp handler by [@​jgimenez](https://togithub.com/jgimenez) in [klauspost/compress#799 #### New Contributors - [@​jgimenez](https://togithub.com/jgimenez) made their first contribution in [klauspost/compress#799 **Full Changelog**: klauspost/compress@v1.16.3...v1.16.4 </details> --- ### Configuration 📅 **Schedule**: Branch creation - "before 3am on the first day of the month" (UTC), Automerge - At any time (no schedule defined). 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this PR and you won't be reminded about this update again. --- - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box --- This PR has been generated by [Renovate Bot](https://togithub.com/renovatebot/renovate). <!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzNS42Ni4zIiwidXBkYXRlZEluVmVyIjoiMzUuNjYuMyIsInRhcmdldEJyYW5jaCI6Im1haW4ifQ==-->
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) This PR contains the following updates: | Package | Type | Update | Change | |---|---|---|---| | [github.com/klauspost/compress](https://togithub.com/klauspost/compress) | indirect | patch | `v1.16.0` -> `v1.16.6` | --- ### Release Notes <details> <summary>klauspost/compress (github.com/klauspost/compress)</summary> ### [`v1.16.6`](https://togithub.com/klauspost/compress/releases/tag/v1.16.6) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.5...v1.16.6) #### What's Changed - zstd: correctly ignore WithEncoderPadding(1) by [@​ianlancetaylor](https://togithub.com/ianlancetaylor) in [klauspost/compress#806 - gzhttp: Handle informational headers by [@​rtribotte](https://togithub.com/rtribotte) in [klauspost/compress#815 - zstd: Add amd64 match length assembly by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#824 - s2: Improve Better compression slightly by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#663 - s2: Clean up matchlen assembly by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#825 #### New Contributors - [@​rtribotte](https://togithub.com/rtribotte) made their first contribution in [klauspost/compress#815 - [@​dveeden](https://togithub.com/dveeden) made their first contribution in [klauspost/compress#816 **Full Changelog**: klauspost/compress@v1.16.5...v1.16.6 ### [`v1.16.5`](https://togithub.com/klauspost/compress/releases/tag/v1.16.5) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.4...v1.16.5) #### What's Changed - zstd: readByte needs to use io.ReadFull by [@​jnoxon](https://togithub.com/jnoxon) in [klauspost/compress#802 - gzip: Fix WriterTo after initial read by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#804 #### New Contributors - [@​jnoxon](https://togithub.com/jnoxon) made their first contribution in [klauspost/compress#802 **Full Changelog**: klauspost/compress@v1.16.4...v1.16.5 ### [`v1.16.4`](https://togithub.com/klauspost/compress/releases/tag/v1.16.4) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.3...v1.16.4) #### What's Changed - s2: Fix huge block overflow by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#779 - s2: Allow CustomEncoder fallback by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#780 - zstd: Fix amd64 not always detecting corrupt data by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#785 - zstd: Improve zstd best efficiency by [@​klauspost](https://togithub.com/klauspost) and [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#784 - zstd: Make load(32|64)32 safer and smaller by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#788 - zstd: Fix quick reject on long backmatches by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#787 - zstd: Revert table size change by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#789 - zstd: Respect WithAllLitEntropyCompression by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#792 - zstd: Fix back-referenced offset by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#793 - zstd: Load source value at start of loop by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#794 - zstd: Shorten checksum code by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#795 - zstd: Fix fallback on incompressible block by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#798 - gzhttp: Suppport ResponseWriter Unwrap() in gzhttp handler by [@​jgimenez](https://togithub.com/jgimenez) in [klauspost/compress#799 #### New Contributors - [@​jgimenez](https://togithub.com/jgimenez) made their first contribution in [klauspost/compress#799 **Full Changelog**: klauspost/compress@v1.16.3...v1.16.4 ### [`v1.16.3`](https://togithub.com/klauspost/compress/releases/tag/v1.16.3) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.2...v1.16.3) **Full Changelog**: klauspost/compress@v1.16.2...v1.16.3 ### [`v1.16.2`](https://togithub.com/klauspost/compress/releases/tag/v1.16.2) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.1...v1.16.2) #### What's Changed - Fix Goreleaser permissions by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#777 **Full Changelog**: klauspost/compress@v1.16.1...v1.16.2 ### [`v1.16.1`](https://togithub.com/klauspost/compress/releases/tag/v1.16.1) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.0...v1.16.1) #### What's Changed - zstd: Speed up + improve best encoder by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#776 - s2: Add Intel LZ4s converter by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#766 - gzhttp: Add BREACH mitigation by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#762 - gzhttp: Remove a few unneeded allocs by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#768 - gzhttp: Fix crypto/rand.Read usage by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#770 - gzhttp: Use SHA256 as paranoid option by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#769 - gzhttp: Use strings for randomJitter to skip a copy by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#767 - zstd: Fix ineffective block size check by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#771 - zstd: Check FSE init values by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#772 - zstd: Report EOF from byteBuf.readBig by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#773 - huff0: Speed up compress1xDo by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#774 - tests: Remove fuzz printing by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#775 - tests: Add CICD Fuzz testing by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#763 - ci: set minimal permissions to GitHub Workflows by [@​diogoteles08](https://togithub.com/diogoteles08) in [klauspost/compress#765 #### New Contributors - [@​diogoteles08](https://togithub.com/diogoteles08) made their first contribution in [klauspost/compress#765 **Full Changelog**: klauspost/compress@v1.16.0...v1.16.1 </details> --- ### Configuration 📅 **Schedule**: Branch creation - 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This PR contains the following updates: | Package | Type | Update | Change | |---|---|---|---| | [github.com/klauspost/compress](https://togithub.com/klauspost/compress) | indirect | minor | `v1.15.15` -> `v1.16.7` | --- ### Release Notes <details> <summary>klauspost/compress (github.com/klauspost/compress)</summary> ### [`v1.16.7`](https://togithub.com/klauspost/compress/releases/tag/v1.16.7) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.6...v1.16.7) #### What's Changed - zstd: Fix default level first dictionary encode by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#829 - docs: Fix typo in security advisory URL by [@​vcabbage](https://togithub.com/vcabbage) in [klauspost/compress#830 - s2: add GetBufferCapacity() method by [@​GiedriusS](https://togithub.com/GiedriusS) in [klauspost/compress#832 #### New Contributors - [@​vcabbage](https://togithub.com/vcabbage) made their first contribution in [klauspost/compress#830 - [@​GiedriusS](https://togithub.com/GiedriusS) made their first contribution in [klauspost/compress#832 **Full Changelog**: klauspost/compress@v1.16.6...v1.16.7 ### [`v1.16.6`](https://togithub.com/klauspost/compress/releases/tag/v1.16.6) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.5...v1.16.6) #### What's Changed - zstd: correctly ignore WithEncoderPadding(1) by [@​ianlancetaylor](https://togithub.com/ianlancetaylor) in [klauspost/compress#806 - gzhttp: Handle informational headers by [@​rtribotte](https://togithub.com/rtribotte) in [klauspost/compress#815 - zstd: Add amd64 match length assembly by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#824 - s2: Improve Better compression slightly by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#663 - s2: Clean up matchlen assembly by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#825 #### New Contributors - [@​rtribotte](https://togithub.com/rtribotte) made their first contribution in [klauspost/compress#815 - [@​dveeden](https://togithub.com/dveeden) made their first contribution in [klauspost/compress#816 **Full Changelog**: klauspost/compress@v1.16.5...v1.16.6 ### [`v1.16.5`](https://togithub.com/klauspost/compress/releases/tag/v1.16.5) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.4...v1.16.5) #### What's Changed - zstd: readByte needs to use io.ReadFull by [@​jnoxon](https://togithub.com/jnoxon) in [klauspost/compress#802 - gzip: Fix WriterTo after initial read by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#804 #### New Contributors - [@​jnoxon](https://togithub.com/jnoxon) made their first contribution in [klauspost/compress#802 **Full Changelog**: klauspost/compress@v1.16.4...v1.16.5 ### [`v1.16.4`](https://togithub.com/klauspost/compress/releases/tag/v1.16.4) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.3...v1.16.4) #### What's Changed - s2: Fix huge block overflow by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#779 - s2: Allow CustomEncoder fallback by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#780 - zstd: Fix amd64 not always detecting corrupt data by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#785 - zstd: Improve zstd best efficiency by [@​klauspost](https://togithub.com/klauspost) and [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#784 - zstd: Make load(32|64)32 safer and smaller by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#788 - zstd: Fix quick reject on long backmatches by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#787 - zstd: Revert table size change by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#789 - zstd: Respect WithAllLitEntropyCompression by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#792 - zstd: Fix back-referenced offset by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#793 - zstd: Load source value at start of loop by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#794 - zstd: Shorten checksum code by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#795 - zstd: Fix fallback on incompressible block by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#798 - gzhttp: Suppport ResponseWriter Unwrap() in gzhttp handler by [@​jgimenez](https://togithub.com/jgimenez) in [klauspost/compress#799 #### New Contributors - [@​jgimenez](https://togithub.com/jgimenez) made their first contribution in [klauspost/compress#799 **Full Changelog**: klauspost/compress@v1.16.3...v1.16.4 ### [`v1.16.3`](https://togithub.com/klauspost/compress/releases/tag/v1.16.3) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.2...v1.16.3) **Full Changelog**: klauspost/compress@v1.16.2...v1.16.3 ### [`v1.16.2`](https://togithub.com/klauspost/compress/releases/tag/v1.16.2) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.1...v1.16.2) #### What's Changed - Fix Goreleaser permissions by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#777 **Full Changelog**: klauspost/compress@v1.16.1...v1.16.2 ### [`v1.16.1`](https://togithub.com/klauspost/compress/releases/tag/v1.16.1) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.16.0...v1.16.1) #### What's Changed - zstd: Speed up + improve best encoder by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#776 - s2: Add Intel LZ4s converter by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#766 - gzhttp: Add BREACH mitigation by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#762 - gzhttp: Remove a few unneeded allocs by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#768 - gzhttp: Fix crypto/rand.Read usage by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#770 - gzhttp: Use SHA256 as paranoid option by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#769 - gzhttp: Use strings for randomJitter to skip a copy by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#767 - zstd: Fix ineffective block size check by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#771 - zstd: Check FSE init values by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#772 - zstd: Report EOF from byteBuf.readBig by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#773 - huff0: Speed up compress1xDo by [@​greatroar](https://togithub.com/greatroar) in [klauspost/compress#774 - tests: Remove fuzz printing by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#775 - tests: Add CICD Fuzz testing by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#763 - ci: set minimal permissions to GitHub Workflows by [@​diogoteles08](https://togithub.com/diogoteles08) in [klauspost/compress#765 #### New Contributors - [@​diogoteles08](https://togithub.com/diogoteles08) made their first contribution in [klauspost/compress#765 **Full Changelog**: klauspost/compress@v1.16.0...v1.16.1 ### [`v1.16.0`](https://togithub.com/klauspost/compress/releases/tag/v1.16.0) [Compare Source](https://togithub.com/klauspost/compress/compare/v1.15.15...v1.16.0) #### What's Changed - s2: Add Dictionary support by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#685 - s2: Add Compression Size Estimate by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#752 - s2: Add support for custom stream encoder by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#755 - s2: Add LZ4 block converter by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#748 - s2: Support io.ReaderAt in ReadSeeker by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#747 - s2c/s2sx: Use concurrent decoding by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#746 - tests: Upgrade to Go 1.20 by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#749 - Update all (command) dependencies by [@​klauspost](https://togithub.com/klauspost) in [klauspost/compress#758 **Full Changelog**: klauspost/compress@v1.15.15...v1.16.0 </details> --- ### Configuration 📅 **Schedule**: Branch creation - "before 4am on the first day of the month" (UTC), Automerge - At any time (no schedule defined). 🚦 **Automerge**: Disabled by config. 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Regression from #784 and followup #793 Fixes #875 A 0 offset backreference was possible when "improve" was successful twice in a row in the "skipBeginning" part, only finding 2 (previously unmatches) length 4 matches, but where start offset decreased by 2 in both cases. This would result in output where the end offset would equal to the next 's', thereby doing a self-reference. Add a general check in "improve" and just reject these. Will also guard against similar issues in the future. This also hints at some potentially suboptimal hash indexing - but I will take that improvement separately. Fuzz test set updated.
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* zstd: Fix corrupted output in "best" Regression from #784 and followup #793 Fixes #875 A 0 offset backreference was possible when "improve" was successful twice in a row in the "skipBeginning" part, only finding 2 (previously unmatches) length 4 matches, but where start offset decreased by 2 in both cases. This would result in output where the end offset would equal to the next 's', thereby doing a self-reference. Add a general check in "improve" and just reject these. Will also guard against similar issues in the future. This also hints at some potentially suboptimal hash indexing - but I will take that improvement separately. Fuzz test set updated.
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Since we expand backwards early, we may be in a situation where best.s+2 has already been indexed.
This will result in picking up a 0 or negative offset, which leads to corrupted data.
Skip this check if best.s is less than or equal to s-2.
Regression from #784 (not released)