On Wed, Jul 04, 2012 at 06:08:59AM -0600, Eric Blake wrote: > [adding gnulib] > > On 07/04/2012 02:45 AM, Daniel P. Berrange wrote: > > >>> ==6825== > >>> ==6825== Invalid read of size 4 > >>> ==6825== at 0xA57E4B9: base64_encode (in /usr/lib/x86_64-linux-gnu/libroken.so.18.1.0) > >>> ==6825== by 0x10DDBC98: base64_encode_alloc (base64.c:140) > > >>> > >>> This one is very interesting. It shows that the 'base64_encode' function > >>> is doing an out-of-bounds read. More tellingly though is that it is > >>> reporting 'base64_encode' function is in a wierd library: > >>> > >>> /usr/lib/x86_64-linux-gnu/libroken.so.18.1. > >>> > >>> If this were normal, we should expect to see that function present > >>> in 'base64.c' since this function code is provided by gnulib itself. > >>> > >>> So something else libvirt is linking to, directly or indirectly > >>> is using libroken.so which also has a 'base64_encode'symbol > >>> defined. This is overriding gnulib's symbol of the same name. > >>> > >>> I'm willing to bet the API contract of this libroken.so base64_encode. > >>> differs from GNULIBS, with crashtastic results > >>> > > >> The library is libroken18-heimdal under Ubuntu 12.04: > >> http://packages.ubuntu.com/precise/libroken18-heimdal > >> > >> When installing ubuntu-virt-server libraries like gnutls depend on > >> this library. > >> > > > I expect that this is an internal symbol from libroken.so which > > they leak into the public namespace. > > > > > It sounds like we might need to have a workaround in gnulib to > > avoid this problem. With other cases where gnulib replaces existing > > symbols they use some magic such that the gnulib replacement gets > > prefixed with 'rpl_'. > > Yuck. Gnulib can't really probe at configure time whether an > application will link against a shared library that drags in namespace > pollution, so I don't see how to automate any 'rpl_' renaming in gnulib > directly. It would be possible to blindly rename the gnulib functions, > but that's an interface change that would affect all clients of the > gnulib base64 module. > > I'm wondering if it is better for libvirt to just #define base64_encode > to a different name in config.h. Yeah, that's sort of what I was imagining we could do in base64.h in fact. If its better to just do it in libvirt config.h, then we can do that too Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :| -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list