-
Notifications
You must be signed in to change notification settings - Fork 616
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
re-order shift/compare in FastHuf to prevent undefined shift overflow #819
re-order shift/compare in FastHuf to prevent undefined shift overflow #819
Conversation
… warning Signed-off-by: Peter Hillman <peterh@wetafx.co.nz>
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
LGTM.
If this was inspired by an ozz-fuzz issue, can you add a reference to it in the comments here, for tracking purposes? |
|
… 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>
…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>
UndefinedBehaviorSanitizer warns at
bufferBack = bufferBack << numBits
when numBits is too large, as that is an undefined operation. In practice this is safe becausebufferBack
was 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