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Bump cld2 to fix MSan use-of-uninitialized-value in detectLanguage#104257
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`CLD2::ScriptScanner` had two paths that read one byte past the input buffer when a consumed UTF-8 character ended exactly at `byte_length_`. With a `ColumnString` whose trailing padding bytes are uninitialized, this tripped MSan in `detectLanguageMixed` (and the other `detectLanguage*` functions) and showed up as flaky failures of the `function_prop_fuzzer` unit test on master. Patched in `ClickHouse/cld2#3`. Add a stateless test that exercises the boundary, including the inputs reported on the issue. Closes ClickHouse#103765 Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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CLD2::ScriptScannerhad two paths that read one byte past the input buffer when a consumed UTF-8 character ended exactly atbyte_length_. With aColumnStringwhose trailing padding bytes are uninitialized, this tripped MSan indetectLanguageMixed(and the otherdetectLanguage*functions) and showed up as flaky failures of thefunction_prop_fuzzerunit test on master.Patched in ClickHouse/cld2#3 — guards the lookahead in
GetOneScriptSpanand the post-loop back-up inGetOneTextSpanagainsttake == byte_length_.Reproduced and confirmed fixed against an MSan build:
Closes #103765
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Changelog entry (a user-readable short description of the changes that goes into CHANGELOG.md):
Fix
MemorySanitizer: use-of-uninitialized-valueindetectLanguage*functions when the input contains a UTF-8 character ending exactly at the buffer boundary.Documentation entry for user-facing changes
Version info
26.5.1.381