Bug#818037: vorbis-tools: vcut always(?) segfaults

[Martin Steghöfer]

tags 818037 + pending
thanks


Frank Heckenbach wrote:
> Sorry for the brief description, but for what I can tell, that's
> really it. I tried various cases, and vcut always seems to just
> segfault. Here's one example:
>
> % head -c 500000 /dev/zero | oggenc -Q -r -o 1.ogg -
> % vcut 1.ogg 2.ogg 3.ogg +1
> Processing: Cutting at 1,000000 seconds
> Segmentation fault
>
> Tried on both i386 and amd64.
>
> It did work correctly under squeeze and wheezy.

Thanks for the report!

I debugged it and found the problem. It was a simple indexing problem 
that seemed to have slipped away during quite some time because of a 
lucky memory layout: The pointer resulting from the wrong indexing 
points to the stack and therefore to valid memory (in terms of memory 
management), unless the block is too big. Now the memory layout has 
changed for some reason (GCC 5?), therefore we read a different value as 
block size, the block is too big for the stack and we get the 
segmentation faults.

The patch is in the git repository.

Cheers,
Martin