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IiqDecoder: bounds-check row in bad-pixel defect handling - #994
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LebedevRI merged 2 commits intoOct 8, 2026
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PR darktable-org#965 added a bounds check for `col` in the bad-column path of correctSensorDefects(), but the bad-pixel path (case 129) in the same switch validates `col` and not `row`. An attacker-controlled row value (up to 65535) flows via mBadPixelPositions into transferBadPixelsToMap, which writes mBadPixelMap[(pitch * pos_y) + (pos_x >> 3)] guarded only by asserts — a heap OOB write in release builds.
LebedevRI
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Oct 8, 2026
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Done: moved the bounds check into |
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@kalt2212 thank you! |
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Summary
Fixes a heap-buffer-overflow WRITE in the IIQ decoder's bad-pixel defect handling.
Details
PR #965 ("bounds-check col before correctBadColumn") covered the bad-column path but missed the bad-pixel path (
case 129) in the same switch ofcorrectSensorDefects(). Both are fed by the same attacker-controlled tag (IIQ 0x400 "Sensor Defects"). The code validatescolbut notrow(uint16_t, up to 65535).The unchecked
rowflows viamBadPixelPositionsintotransferBadPixelsToMap()(RawImage.cpp), which writesmBadPixelMap[(pitch * pos_y) + (pos_x >> 3)]guarded only byasserts — a heap OOB write in release builds, abort/DoS with asserts. Reachable by default (interpolateBadPixels=true).PoC with ASan: exact sink replica,
row=65535→ SEGV on WRITE.Testing
ASan PoC confirms the OOB write before the fix; clean after.
AI tool use disclosure: AI was used in part for code audit and patch drafting.