Bug#677035: libavcodec52: SEGV when encoding video

[g.bonacci at libero.it]

On Mon, Jun 11, 2012 at 12:05:05PM +0200, Reinhard Tartler wrote:
> 
> In order to check if that bug has already been fixed upstream, could
> you please install the libavcodec-extra-53 package from backports.org
> and check if the segmentation fault still occurs?
> 

I've just tried libav-tools 4:0.8-2~bpo60+1 and libavcodec53 segfaults too, so
perhaps the problem is present upstream.

After my submission, I've noticed that it crashes with horizontal sizes
626, 632, and 852, but not with sizes 624 and 640.

Coupled with the name of the top-of-stack function (sad16_sse2), that suggests
a workaround: use horizontal sizes that are multiples of 16.

Although I've had no time to examine the code (and I'm no expert in assembly)
I guess that the problem might be caused by a wrongly aligned or sized buffer.

Regards,
	g