[FFmpeg-devel] libavutil/imgutils: UBSan nullptr-with-offset in av_image_fill_pointer

[Michael Niedermayer]

On Wed, Jul 01, 2020 at 11:14:13AM -0700, Brian Kim wrote:
> While running under Clang's UndefinedBehaviorSanitizer, I found a few
> places where av_image_fill_pointers is called before buffers for the image
> are allocated, so ptr is passed in as NULL.
> 
> This leads to (currently harmless) UB when the plane sizes are added to the
> null pointer, so I was wondering if there was interest in avoiding it?
> 
> I've attached a patch to expose some extra utilities and avoid passing in
> the null pointer, but is this an appropriate way to work around it?

how can these cases be reproduced ?

thx

[...]
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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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