[MPlayer-dev-eng] mplayer -pie and libbluray

[Reimar Döffinger]

On Wed, Aug 15, 2012 at 07:45:59PM +0200, Alexander Roalter wrote:
> On 08/15/2012 07:14 PM, Reimar Döffinger wrote:
> >Hello,
> >
> >On Wed, Aug 15, 2012 at 11:51:29AM +0200, Alexander Roalter wrote:
> >>When I compile a recent mplayer (on x86_64) and start with br://1, I
> >>get a segfault in libbluray, because a strdup called there doesn't
> >>deliver a valid result.
> >
> >I disabled it again by default, as Ivan reminded me there is another
> >issue open...
> >Can you in any way help debug this?
> >I am running Debian unstable x86_64 and it works just fine (I've used this
> >patch since about March without any issues...).
> 
> I'm using a rather old-ish Opensuse 11.2.
> 
> If you point me in some direction (what to look for, e.g. loader,
> libraries etc.) I can certainly help. Did you also run libbluray?
> Perhaps it is something specific to that lib...

Yes, I tried playing a bluray, with both br:// and bd:// just to be sure.
I can't know for sure it hit the code-path that caused your issue.
Something like a backtrace of the crash and/or strdup and what the
pointer value looks like or so might help.
Maybe some kind of minimal reproduction case, like
char *a(void){ return strdup("test") };
compiled to a .so and a normal program compiled as PIE linking
against it to see if that also triggers the issue?
Or maybe figure out how address randomization is configured on your
system? Maybe changing that will determine if there is a problem or not?
However I can't really understand why it would work in valgrind,
except that I'd guess it ends up not using address randomization.