[FFmpeg-devel] [PATCH 1/4] avcodec/rtv1: Check if the minimal size is available in decode_rtv1()

[Paul B Mahol]

On 9/22/23, Michael Niedermayer <michael at niedermayer.cc> wrote:
> On Fri, Sep 22, 2023 at 09:32:47PM +0200, Paul B Mahol wrote:
>> On 9/22/23, Michael Niedermayer <michael at niedermayer.cc> wrote:
>> > On Thu, Jul 27, 2023 at 01:59:13AM +0200, Michael Niedermayer wrote:
>> >> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
>> >> ---
>> >>  libavcodec/rtv1.c | 6 +++++-
>> >>  1 file changed, 5 insertions(+), 1 deletion(-)
>> >
>> > will apply 1-3 of this patchset
>>
>> Are you sure this does not break decoding?
>
> Well, its a loop over 4x4 blocks, a 16bit "skip" run so the minimum
> check looks correct.
> There are 2 end of bitstream checks for early exit but they look like
> error handling not some normal exit as they leave the frame uninitialized
>

FFmpeg default initialization code for AVFrame's buffers does it
twice, so they are always zeroed or previous values of previous
buffers in pool.

> Do you have some files so i can double check this is not breaking anything

Search trac tickets.

> ?
>
> thx
>
> [...]
> --
> Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
>
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>