[FFmpeg-devel] [PATCH 12/19] avcodec/mpegvideo_enc: Don't segfault on unorthodox mpeg_quant

Michael Niedermayer michael at niedermayer.cc
Thu Apr 8 00:05:27 EEST 2021


On Tue, Apr 06, 2021 at 11:55:09PM +0200, Andreas Rheinhardt wrote:
> The (deprecated) field AVCodecContext.mpeg_quant has no range
> restriction; MpegEncContext.mpeg_quant is restricted to 0..1.
> If the former is set, the latter is overwritten with it without
> checking the range. This can trigger an av_assert2() with the MPEG-4
> encoder when writing said field.
> 
> Fix this by just setting MpegEncContext.mpeg_quant to 1 if
> AVCodecContext.mpeg_quant is set.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
> This can not be triggered if one only sets options via the dictionary in
> avcodec_open2(); one needs to set it directly in the AVCodecContext or
> use the private class of AVCodecContext.

I tend toward checking mpeg_quant to be valid in init somewhere but this
here is fine too or in addition

thx

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Modern terrorism, a quick summary: Need oil, start war with country that
has oil, kill hundread thousand in war. Let country fall into chaos,
be surprised about raise of fundamantalists. Drop more bombs, kill more
people, be surprised about them taking revenge and drop even more bombs
and strip your own citizens of their rights and freedoms. to be continued
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 195 bytes
Desc: not available
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20210407/27f41c7e/attachment.sig>


More information about the ffmpeg-devel mailing list