Comment 6 for bug 667269

I didn't specifically reproduce the problem, but the problem has happened, on its own.
There also happens to be a recent core file around.

    $ sudo find /var/log -type f | grep core | xargs sudo ls -al
    -rw------- 1 root root 1564672 2010-12-27 04:12 /var/log/samba/cores/winbindd/core

I then run `gdb winbindd`, "core core", and then "bt" for a backtrace:

Program terminated with signal 6, Aborted.
#0 0x00007f5862af1a75 in raise () from /lib/libc.so.6
(gdb) bt
#0 0x00007f5862af1a75 in raise () from /lib/libc.so.6
#1 0x00007f5862af55c0 in abort () from /lib/libc.so.6
#2 0x00007f5864f97430 in dump_core () at lib/fault.c:337
#3 0x00007f5864fa825e in smb_panic (why=<value optimized out>) at lib/util.c:1496
#4 0x00007f5864f9782d in fault_report (sig=11) at lib/fault.c:52
#5 sig_fault (sig=11) at lib/fault.c:75
#6 <signal handler called>
#7 get_cache (domain=0x0) at winbindd/winbindd_cache.c:139
#8 0x00007f5864f0a888 in resolve_username_to_alias (mem_ctx=<value optimized out>, domain=0x0, name=0x7f5866dadf70 "puneet.arora", alias=0x7fff22b0bb00)
    at winbindd/winbindd_cache.c:1019
#9 0x00007f5864efd016 in normalize_name_map (mem_ctx=0x7f5866d56530, domain=0x0, name=0x7f5866dadf70 "puneet.arora", normalized=0x7fff22b0bb00)
    at winbindd/winbindd_util.c:1442
#10 0x00007f5864efb6ef in fill_grent_mem_domusers (domain=0x7f5866db2d60, state=<value optimized out>, group_sid=0x7f5866d6eed0,
    group_name_type=<value optimized out>, num_gr_mem=<value optimized out>, gr_mem=<value optimized out>, gr_mem_len=0x7fff22b0beb8)
    at winbindd/winbindd_group.c:330
#11 fill_grent_mem (domain=0x7f5866db2d60, state=<value optimized out>, group_sid=0x7f5866d6eed0, group_name_type=<value optimized out>,
    num_gr_mem=<value optimized out>, gr_mem=<value optimized out>, gr_mem_len=0x7fff22b0beb8) at winbindd/winbindd_group.c:578
#12 0x00007f5864efba9f in getgrsid_sid2gid_recv (private_data=0x7f5866d6eeb0, success=<value optimized out>, gid=563) at winbindd/winbindd_group.c:866
#13 0x00007f5864ef4b98 in process_loop (argc=<value optimized out>, argv=<value optimized out>, envp=<value optimized out>) at winbindd/winbindd.c:1109
#14 main (argc=<value optimized out>, argv=<value optimized out>, envp=<value optimized out>) at winbindd/winbindd.c:1434

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