rtld segfaults [Was Re: Process stuck in vmmaps on 8.0-BETA1]

On Mon, Jul 13, 2009 at 08:44:48PM +1000, John Marshall wrote:
> On Sat, 11 Jul 2009, 15:42 +0300, Kostik Belousov wrote:
> > On Sat, Jul 11, 2009 at 07:10:50PM +1000, John Marshall wrote:
> > > On Fri, 10 Jul 2009, 16:24 +0300, Kostik Belousov wrote:
> > > >
> > > > Thank you, I see what is going on. Please, try the following patch.
> > > 
> > > Thank you Kostik,
> > > 
> > > I applied your patch to vm_map.c and rebuilt the kernel.  Now the
> > > process crashes instead - but I think it is getting beyond the point
> > > where it was hanging.
> > > 
> > > I rebuilt ntpd on the patched kernel and it still produces this crash.
> > 
> > This is obviously different issue. Besiddes, backtrace does not make
> > much sense.
> > 
> > You need to rebuild and install lib/libc, lib/libthr and
> > libexec/rtld-elf with debugging symbols. Easiest way to do this is to
> > enter into each listed src/ subdirectory and do
> > 	make obj
> > 	make clean
> > 	make depend
> > 	make all install DEBUG_FLAGS=-g
> > and then start ntpd again and get the backtrace, might by "bt full" will
> > be more informative.
> 
> Thank you for the help.  This is what I saw after following your
> instructions...
> 
> (gdb) bt full
> #0  memset () at /usr/src/lib/libc/i386/string/memset.S:78
> No locals.
> #1  0x00006000 in ?? ()
> No symbol table info available.
> #2  0x28085c9b in map_object (fd=6, 
>     path=0x280c0080 "/usr/local/lib/nss_winbind.so.1", sb=0xbfbfdbac)
>     at /usr/src/libexec/rtld-elf/map_object.c:196
> 	obj = Variable "obj" is not available.
> Current language:  auto; currently asm
> 
> > BTW, do you use NIS ?
> 
> Yes, and I also have winbind.  If I remove winbind from
> /etc/nsswitch.conf then ntpd runs happily.  I suspect that this might be
> related to the GSSAPI authentication not working for sshd.  I shall now
> turn my attention to that problem.
> 
> Thank you for your help in resolving the initial vmmaps problem - and
> for your patch to vm_map.c.  I think we've progressed far enough beyond
> that problem to close this thread.
This still seems to be a system bug, but now in the rtld.

I need two things:
1. ktrace/kdump output for ntpd start that causes the process to crash;
2. readelf -a /usr/local/lib/nss_winbind.so.1
(both may be large enough, so that it is better to put it somewhere on
web server).