fix: clamp numMasksInChunk to prevent heap-buffer-overflow in EmbeddingExtractor#398
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Alex-Wengg merged 1 commit intoFluidInference:mainfrom Mar 19, 2026
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…ngExtractor When audio.count > 160,000 samples (>10s at 16kHz), the numMasksInChunk formula `(firstMask.count * audio.count + 80_000) / 160_000` produces a value larger than firstMask.count. This causes vDSP_mmov in fillMaskBufferOptimized() to read past the mask buffer allocation. For example, with maskCount=100 and 20s audio (320k samples): buggy: (100 * 320000 + 80000) / 160000 = 200 — 2x overread fixed: min(200, 100) = 100 The fix clamps numMasksInChunk to firstMask.count with min(). Bug introduced in v0.8.0 (PR FluidInference#191, 2025-11-26). Affects v0.8.0–v0.12.4. Detected via AddressSanitizer: READ of size 3456 from 2388-byte buffer. Includes regression tests validating the formula and vDSP_mmov bounds. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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When audio.count > 160,000 samples (>10s at 16kHz), the numMasksInChunk formula
(firstMask.count * audio.count + 80_000) / 160_000produces a value larger than firstMask.count. This causes vDSP_mmov in fillMaskBufferOptimized() to read past the mask buffer allocation.For example, with maskCount=100 and 20s audio (320k samples):
buggy: (100 * 320000 + 80000) / 160000 = 200 — 2x overread
fixed: min(200, 100) = 100
The fix clamps numMasksInChunk to firstMask.count with min().
Bug introduced in v0.8.0 (PR #191, 2025-11-26). Affects v0.8.0–v0.12.4. Detected via AddressSanitizer: READ of size 3456 from 2388-byte buffer.
Includes regression tests validating the formula and vDSP_mmov bounds.