[Bug 48927] Heap buffer underflow in TiffFrameDecode_ReadTile when decoding 1x1 4bpp RGBA image

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=48927

Dmitry Timoshkov  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #2 from Dmitry Timoshkov  ---
(In reply to Thomas Faber from comment #1)
> Created attachment 66888 [details]
> Possible fix
>
> Attaching a possible fix (line numbers may not match but context should).
>
> I'm not sure of the proper process for updating someone else's patch in
> Staging. Happy to follow it if preferred, or someone can just fix it
> directly.

While the compiler usually should be able to optimize this code it's always
preferable to use '& 1' instead of '%2'.

Does using simple
if (!(This->decode_info.tile_width & 1))
help?