fix: prevent panic when reading empty WAL index file (#737)#912
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mattisonchao merged 1 commit intomainfrom Feb 26, 2026
Merged
fix: prevent panic when reading empty WAL index file (#737)#912mattisonchao merged 1 commit intomainfrom
mattisonchao merged 1 commit intomainfrom
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When the .idxx index file is empty (0 bytes), ReadIndex() would panic with "slice bounds out of range [4:0]" when trying to read the CRC at offset 0. This fix adds a length check before reading the index. If the file is shorter than the header size (4 bytes), it returns ErrDataCorrupted instead of panicking, allowing the caller to rebuild the index from the txn file. Added tests: - TestV2_ReadEmptyIndex: verifies empty file handling - TestV2_ReadShortIndex: verifies short file (<4 bytes) handling Fixes #737
mattisonchao
approved these changes
Feb 26, 2026
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Problem
When the .idxx index file is empty (0 bytes),
ReadIndex()would panic withslice bounds out of range [4:0]when trying to read the CRC at offset 0.Stack trace from #737:
Solution
Added a length check before reading the index. If the file is shorter than the header size (4 bytes), it returns
ErrDataCorruptedinstead of panicking, allowing the caller (readonly_segment.go) to rebuild the index from the txn file.Changes
oxiad/dataserver/wal/codec/v2.go: Added length check inReadIndex()oxiad/dataserver/wal/codec/v2_test.go: Added tests for empty and short index filesTest Plan
Both tests pass:
TestV2_ReadEmptyIndex: verifies empty file (0 bytes) returnsErrDataCorruptedTestV2_ReadShortIndex: verifies short file (<4 bytes) returnsErrDataCorruptedFixes #737