Fix ARM64 UBSan pointer overflow in GetConstSegmentForCode - #294
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Fix ARM64 UBSan pointer overflow in GetConstSegmentForCode#294aravinth-kanesh wants to merge 1 commit into
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Cast the divisor to POLYSIGNED so a negative offset is not promoted to unsigned before the division. Without the cast, offset / sizeof(PolyWord) converts the negative offset to a large unsigned value, and the resulting pointer addition overflows (UBSan: addition of unsigned offset overflowed). Fixes polyml#271.
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Fixes #271.
Casts the divisor to POLYSIGNED so the negative offset isn't promoted to unsigned before the division. Without the cast, offset / sizeof(PolyWord) converts the negative offset to a large unsigned value and the resulting pointer addition overflows (UBSan: addition of unsigned offset overflowed).
Validated locally - both reproducers in #271 no longer trigger the UBSan violation.