[Samba] Internal Error: Signal 11 in winbindd log when authenticating against AD

[Dave Bundus]

After upgrading to freeradius 2.2.9 and winbindd 4.1.6 on Ubuntu 14:03 I
began receiving the below messages in the winbindd log.  These messages did
not happen when testing under a low volume of requests, but now in
production I am receiving approximately 100 of these messages per hour.
The same error message occurs on 3 servers sharing the same configuration.

After the message is posted to the log.  Successful logins immediately
resume. This error has not kept a user from logging in.  The AD servers I
am authenticating against are running server 2012 R2

INTERNAL ERROR: Signal 11 in pid 4569 (4.1.6-Ubuntu)
Please read the Trouble-Shooting section of the Samba HOWTO
[2015/12/06 15:22:01.936253,  0] ../lib/util/fault.c:75(fault_report)
===============================================================
[2015/12/06 15:22:01.936329,  0] ../source3/lib/util.c:785(smb_panic_s3)
PANIC (pid 4569): internal error
[2015/12/06 15:22:01.936943,  0] ../source3/lib/util.c:896(log_stack_trace)
 BACKTRACE: 22 stack frames:
 #0 /usr/lib/i386-linux-gnu/libsmbconf.so.0(log_stack_trace+0x29)
[0xb6cc6a39]
 #1 /usr/lib/i386-linux-gnu/libsmbconf.so.0(smb_panic_s3+0x28) [0xb6cc6b38]
 #2 /usr/lib/i386-linux-gnu/libsamba-util.so.0(smb_panic+0x3a) [0xb75d42ba]
 #3 /usr/lib/i386-linux-gnu/libsamba-util.so.0(+0x1a551) [0xb75d4551]
 #4 [0xb761dc8c]
 #5
/usr/lib/i386-linux-gnu/samba/liblibcli_netlogon3.so.0(rpccli_netlogon_sam_network_logon+0x13d)
[0xb72a0f1d]
 #6 /usr/sbin/winbindd(+0x36327) [0xb7677327]
 #7 /usr/sbin/winbindd(winbindd_dual_pam_auth_crap+0x423) [0xb767b753]
 #8 /usr/sbin/winbindd(+0x51c7d) [0xb7692c7d]
 #9 /usr/lib/i386-linux-gnu/libtevent.so.0(+0x8516) [0xb6b34516]
 #10 /usr/lib/i386-linux-gnu/libtevent.so.0(+0x676e) [0xb6b3276e]
 #11 /usr/lib/i386-linux-gnu/libtevent.so.0(_tevent_loop_once+0xa0)
[0xb6b2eca0]
 #12 /usr/sbin/winbindd(+0x546b1) [0xb76956b1]
 #13 /usr/sbin/winbindd(+0x54edd) [0xb7695edd]
 #14 /usr/lib/i386-linux-gnu/libtevent.so.0(+0x38e2) [0xb6b2f8e2]
  #15
/usr/lib/i386-linux-gnu/libtevent.so.0(tevent_common_loop_immediate+0xe8)
[0xb6b2f578]
  #16 /usr/lib/i386-linux-gnu/libtevent.so.0(+0x82b5) [0xb6b342b5]
  #17 /usr/lib/i386-linux-gnu/libtevent.so.0(+0x676e) [0xb6b3276e]
  #18 /usr/lib/i386-linux-gnu/libtevent.so.0(_tevent_loop_once+0xa0)
[0xb6b2eca0]
  #19 /usr/sbin/winbindd(main+0xd23) [0xb765b783]
  #20 /lib/i386-linux-gnu/libc.so.6(__libc_start_main+0xf3) [0xb6996a83]
  #21 /usr/sbin/winbindd(+0x1b005) [0xb765c005]
[2015/12/06 15:22:01.937950,  0] ../source3/lib/util.c:797(smb_panic_s3)
   smb_panic(): calling panic action [/usr/share/samba/panic-action 4569]
: [2015/12/06 15:22:01.940773,  0] ../source3/lib/util.c:805(smb_panic_s3)
:   smb_panic(): action returned status 0
[2015/12/06 15:22:01.940921,  0] ../source3/lib/dumpcore.c:317(dump_core)
dumping core in /var/log/samba/cores/winbindd