re-order shift/compare in FastHuf to prevent undefined shift overflow #819
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… warning Signed-off-by: Peter Hillman <peterh@wetafx.co.nz>
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… warning (AcademySoftwareFoundation#819) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> Co-authored-by: Cary Phillips <cary@ilm.com> Signed-off-by: Peter Hillman <peterh@wetafx.co.nz>
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…tests (#875) * ignore unused bits in B44 mode detection Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * apply #832: use unsigned values in shift to prevent undefined behavior Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * apply #818: compute Huf codelengths using 64 bit to prevent shift overflow Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * apply #817: double-check unpackedBuffer created in DWA uncompress Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * apply #820: suppress sanitizer warnings when writing invalid enums Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * apply #825: Avoid overflow in calculateNumTiles when size=MAX_INT Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * apply #826: restrict maximum tile size to INT_MAX byte limit Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * apply #827: lighter weight reading of Luma-only images via RgbaInputFile Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * refactor channel filling in InputFile API with tiled source Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * handle edge-case of empty framebuffer Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * apply #829: fix buffer overflow check in PIZ decompression Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * Use Int64 in dataWindowForTile to prevent integer overflow (#831) * Use Int64 in dataWindowForTile to prevent integer overflow Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * use signed 64 bit instead for dataWindow calculation Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> Co-authored-by: Cary Phillips <cary@ilm.com> Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * prevent overflow in hufUncompress if nBits is large (#836) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * add sanity check for reading multipart files with no parts (#840) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * reduce B44 _tmpBufferSize (was allocating two bytes per byte) (#843) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * check for valid Huf code lengths (#849) * check for valid Huf code lengths * test non-fast huf decoder in testHuf Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * check 1 part files with 'nonimage' bit have type attribute (#860) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> Co-authored-by: Cary Phillips <cary@ilm.com> Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * Fix overflow computing deeptile sample table size (#861) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * re-order shift/compare in FastHuf to prevent undefined shift overflow warning (#819) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> Co-authored-by: Cary Phillips <cary@ilm.com> Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * more elegant exception handling in exrmaketiled (#841) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * check EXRAllocAligned succeeded to allocate ScanlineInputFile lineBuffers (#844) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * test channels are DCT compressed before DWA decompression (#845) Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> * Merge ABI-compatible changes from #842 Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> Co-authored-by: Cary Phillips <cary@ilm.com>
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UndefinedBehaviorSanitizer warns at
bufferBack = bufferBack << numBitswhen numBits is too large, as that is an undefined operation. In practice this is safe becausebufferBackwas guaranteed to be set to zero in a subsequent check.This change reorders operations to prevent the shift being computed in this case, which prevents the warning.
Signed-off-by: Peter Hillman peterh@wetafx.co.nz