[FFmpeg-devel] [PATCH] mpegtsenc: fix free of adts when not using AAC

[Chris Kennedy]

On Wed, Oct 19, 2011 at 4:10 PM, Michael Niedermayer <michaelni at gmx.at>wrote:

> On Wed, Oct 19, 2011 at 12:12:25AM -0500, Chris Kennedy wrote:
> > On Tue, Oct 18, 2011 at 8:05 PM, Michael Niedermayer <michaelni at gmx.at
> >wrote:
> >
> > > On Wed, Oct 12, 2011 at 09:59:44PM -0500, Chris Kennedy wrote:
> > > > On Wed, Oct 12, 2011 at 10:18:22PM +0000, Carl Eugen Hoyos wrote:
> > > > > Chris Kennedy <bitbytebit <at> gmail.com> writes:
> > > > >
> > > > > Please upload the sample that triggers the segfault for you.
> > > >
> > > > It's actually from a live stream from a clearQAM mpegts broadcast,
> > > > so unfortunately has been impossible to get a file that triggers it.
> > > > It's rare, once every week, and when it happens backtraces always
> > > > point into libavformat somewhere from either the write trailer
> > > > function or read frame function.  Here's the two backtraces I've
> > > > gotten, always seems to be when closing an output context and opening
> > > > a new one for mpegts.
> > >
> > > if you cannot upload a sample then maybe running the stuff under
> > > valgrind might point more clearly to the cause
> > >
> > >
> > This is what it does under valgrind:  This is the write frame one that
> > happens, reading clearQAM HD signals over udp and from clearQAM cards.
> >  There's also a av_read_frame issue too that seems to be either the
> mpegts
> > parser doing something odd or somehow the input context streams changing.
> >  Often times from what I can tell basically when the stream is very
> > 'corrupted' then these cause the input context to get confused (thinking
> the
> > audio codec or settings suddenly change, they don't, and new streams keep
> > appearing).  Then output wise as below, it seems suddenly the packet
> buffer
> > has some frames possibly that have a fully negative large stream index
> value
> > and those cause a crash from trying to reference  a stream with them as
> the
> > index.  So just seems like the whole internal system is being somewhat
> > thrashed by the mpegts packets, admittedly from a probably bad input
> > clearQAM signal.
>
> I tried to fix the issue valgrind pointed too, please test and report
> if the change fixed it or if theres some issue left
>
>
Reporting back that your patch has fixed this issue entirely.  Demuxing is
now able to handle mpegts that was giving segfaults and double free's every
8 to 12 hours before.  Thanks for getting this to work!

Thanks,
Chris


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