Fix deadly-signal crash in CSV segmenter (#718)#718
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Summary:
The CSV segmenter crashed (fatal assertion) when processing input with high token density (e.g., many consecutive separators). The root cause was twofold:
1. `maxNumTokens` was calculated as `min(byteSize, chunkByteSizeMax)`, assuming at most 1 token per byte. But consecutive separators produce 2 tokens per byte (empty field + separator), causing the lexer to exhaust the token buffer before consuming enough bytes.
2. When the token buffer was exhausted mid-chunk, the segmenter's internal consistency checks fired with `logicError`, which triggers a fatal assertion in `ZL_E_create_va` ("Logic errors should never actually be generated").
Fix:
- Increase `maxNumTokens` to `2 * chunkSize + 1` to handle worst-case token density
- Change `logicError` to `node_invalid_input` for defense-in-depth, so any remaining edge cases produce a clean error instead of a crash
Reviewed By: Victor-C-Zhang
Differential Revision: D103001388
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Summary:
The CSV segmenter crashed (fatal assertion) when processing input with high token density (e.g., many consecutive separators). The root cause was twofold:
1. `maxNumTokens` was calculated as `min(byteSize, chunkByteSizeMax)`, assuming at most 1 token per byte. But consecutive separators produce 2 tokens per byte (empty field + separator), causing the lexer to exhaust the token buffer before consuming enough bytes.
2. When the token buffer was exhausted mid-chunk, the segmenter's internal consistency checks fired with `logicError`, which triggers a fatal assertion in `ZL_E_create_va` ("Logic errors should never actually be generated").
Fix:
- Increase `maxNumTokens` to `2 * chunkSize + 1` to handle worst-case token density
- Change `logicError` to `node_invalid_input` for defense-in-depth, so any remaining edge cases produce a clean error instead of a crash
Reviewed By: Victor-C-Zhang
Differential Revision: D103001388
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Summary:
The CSV segmenter crashed (fatal assertion) when processing input with high token density (e.g., many consecutive separators). The root cause was twofold:
1. `maxNumTokens` was calculated as `min(byteSize, chunkByteSizeMax)`, assuming at most 1 token per byte. But consecutive separators produce 2 tokens per byte (empty field + separator), causing the lexer to exhaust the token buffer before consuming enough bytes.
2. When the token buffer was exhausted mid-chunk, the segmenter's internal consistency checks fired with `logicError`, which triggers a fatal assertion in `ZL_E_create_va` ("Logic errors should never actually be generated").
Fix:
- Increase `maxNumTokens` to `2 * chunkSize + 1` to handle worst-case token density
Reviewed By: Victor-C-Zhang
Differential Revision: D103001388
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Summary:
The CSV segmenter crashed (fatal assertion) when processing input with high token density (e.g., many consecutive separators). The root cause was twofold:
1. `maxNumTokens` was calculated as `min(byteSize, chunkByteSizeMax)`, assuming at most 1 token per byte. But consecutive separators produce 2 tokens per byte (empty field + separator), causing the lexer to exhaust the token buffer before consuming enough bytes.
2. When the token buffer was exhausted mid-chunk, the segmenter's internal consistency checks fired with `logicError`, which triggers a fatal assertion in `ZL_E_create_va` ("Logic errors should never actually be generated").
Fix:
- Increase `maxNumTokens` to `2 * chunkSize + 1` to handle worst-case token density
Reviewed By: Victor-C-Zhang
Differential Revision: D103001388
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This pull request has been merged in 6959466. |
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Summary:
The CSV segmenter crashed (fatal assertion) when processing input with high token density (e.g., many consecutive separators). The root cause was twofold:
maxNumTokenswas calculated asmin(byteSize, chunkByteSizeMax), assuming at most 1 token per byte. But consecutive separators produce 2 tokens per byte (empty field + separator), causing the lexer to exhaust the token buffer before consuming enough bytes.When the token buffer was exhausted mid-chunk, the segmenter's internal consistency checks fired with
logicError, which triggers a fatal assertion inZL_E_create_va("Logic errors should never actually be generated").Fix:
maxNumTokensto2 * chunkSize + 1to handle worst-case token densityReviewed By: Victor-C-Zhang
Differential Revision: D103001388