Description of problem:

[stef@stef test]$ sudo systemd-coredumpctl gdb sssd_be
           PID: 8710 (sssd_be)
           UID: 0 (root)
           GID: 0 (root)
        Signal: 11 (SEGV)
     Timestamp: Fr 2014-09-19 15:49:34 CEST (4min 58s ago)
  Command Line: /usr/libexec/sssd/sssd_be --domain ad.baseos.qe --debug-to-files
    Executable: /usr/libexec/sssd/sssd_be
 Control Group: /system.slice/sssd.service
          Unit: sssd.service
         Slice: system.slice
       Boot ID: b053136ee4c14238a140086f0168fc1c
    Machine ID: 69d27b356a94476da859461d3a3bc6fd
      Hostname: stef.ad.baseos.qe
      Coredump: /var/lib/systemd/coredump/core.sssd_be.0.b053136ee4c14238a140086f0168fc1c.8710.1411134574000000.xz
       Message: Process 8710 (sssd_be) of user 0 dumped core.
                
                Stack trace of thread 8710:
                #0  0x00007f3ea4240c69 be_nsupdate_create_ptr_msg (sssd_be)
                #1  0x00007f3e951ce5db sdap_dyndns_update_ptr_step (libsss_ldap_common.so)
                #2  0x00007f3e951ce7c8 sdap_dyndns_update_done (libsss_ldap_common.so)
                #3  0x00007f3ea423fedc be_nsupdate_done (sssd_be)
                #4  0x00007f3ea007f6a8 child_invoke_callback (libsss_child.so)
                #5  0x00007f3ea378c824 tevent_common_loop_immediate (libtevent.so.0)
                #6  0x00007f3ea379106e epoll_event_loop_once (libtevent.so.0)
                #7  0x00007f3ea378f787 std_event_loop_once (libtevent.so.0)
                #8  0x00007f3ea378bfed _tevent_loop_once (libtevent.so.0)
                #9  0x00007f3ea378c18b tevent_common_loop_wait (libtevent.so.0)
                #10 0x00007f3ea378f727 std_event_loop_wait (libtevent.so.0)
                #11 0x00007f3ea39c7913 server_loop (libsss_util.so)
                #12 0x00007f3ea4236613 main (sssd_be)
                #13 0x00007f3e9fad30e0 __libc_start_main (libc.so.6)
                #14 0x00007f3ea42366ca _start (sssd_be)

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Reading symbols from /usr/libexec/sssd/sssd_be...Reading symbols from /usr/lib/debug/usr/libexec/sssd/sssd_be.debug...done.
done.
[New LWP 8710]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Core was generated by `/usr/libexec/sssd/sssd_be --domain ad.baseos.qe --debug-to-files'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007f3ea4240c69 in nsupdate_msg_add_ptr (old_addresses=0x7f3ea53f17b0, remove_af=<optimized out>, ttl=3600, 
    hostname=0x7f3ea53ca860 "stef.ad.baseos.qe", addresses=0x7f3ea53f02c0, 
    update_msg=0x7f3ea53f35b0 "realm AD.BASEOS.QE\nupdate delete 7.f.5.e.2.2.e.f.f.f.1.d.9.1.2.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.d.f.ip6.arpa. in PTR\nsend\n") at src/providers/dp_dyndns.c:309
309	        switch(old_record->addr->ss_family) {
(gdb) bt
#0  0x00007f3ea4240c69 in nsupdate_msg_add_ptr (old_addresses=0x7f3ea53f17b0, remove_af=<optimized out>, ttl=3600, 
    hostname=0x7f3ea53ca860 "stef.ad.baseos.qe", addresses=0x7f3ea53f02c0, 
    update_msg=0x7f3ea53f35b0 "realm AD.BASEOS.QE\nupdate delete 7.f.5.e.2.2.e.f.f.f.1.d.9.1.2.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.d.f.ip6.arpa. in PTR\nsend\n") at src/providers/dp_dyndns.c:309
#1  be_nsupdate_create_ptr_msg (mem_ctx=mem_ctx@entry=0x7f3ea53eefa0, realm=<optimized out>, servername=<optimized out>, 
    hostname=0x7f3ea53ca860 "stef.ad.baseos.qe", ttl=3600, remove_af=<optimized out>, addresses=0x7f3ea53f02c0, old_addresses=0x7f3ea53f17b0, 
    _update_msg=0x7f3ea53ef000) at src/providers/dp_dyndns.c:507
#2  0x00007f3e951ce5db in sdap_dyndns_update_ptr_step (req=req@entry=0x7f3ea53eee10) at src/providers/ldap/sdap_dyndns.c:403
#3  0x00007f3e951ce7c8 in sdap_dyndns_update_done (subreq=0x0) at src/providers/ldap/sdap_dyndns.c:379
#4  0x00007f3ea423fedc in be_nsupdate_done (subreq=0x7f3ea53f7ce0) at src/providers/dp_dyndns.c:1057
#5  0x00007f3ea007f6a8 in child_invoke_callback (ev=<optimized out>, imm=<optimized out>, pvt=<optimized out>) at src/util/child_common.c:616
#6  0x00007f3ea378c824 in tevent_common_loop_immediate (ev=ev@entry=0x7f3ea5384670) at ../tevent_immediate.c:135
#7  0x00007f3ea379106e in epoll_event_loop_once (ev=0x7f3ea5384670, location=<optimized out>) at ../tevent_epoll.c:907
#8  0x00007f3ea378f787 in std_event_loop_once (ev=0x7f3ea5384670, location=0x7f3ea39dab18 "src/util/server.c:587") at ../tevent_standard.c:114
#9  0x00007f3ea378bfed in _tevent_loop_once (ev=ev@entry=0x7f3ea5384670, location=location@entry=0x7f3ea39dab18 "src/util/server.c:587")
    at ../tevent.c:530
#10 0x00007f3ea378c18b in tevent_common_loop_wait (ev=0x7f3ea5384670, location=0x7f3ea39dab18 "src/util/server.c:587") at ../tevent.c:634
#11 0x00007f3ea378f727 in std_event_loop_wait (ev=0x7f3ea5384670, location=0x7f3ea39dab18 "src/util/server.c:587") at ../tevent_standard.c:140
#12 0x00007f3ea39c7913 in server_loop (main_ctx=0x7f3ea5385a40) at src/util/server.c:587
#13 0x00007f3ea4236613 in main (argc=4, argv=<optimized out>) at src/providers/data_provider_be.c:2821
(gdb) p old_record
$1 = (struct sss_iface_addr *) 0x7f3ea53ee710
(gdb) p old_record->addr
$2 = (struct sockaddr_storage *) 0x80

Version-Release number of selected component (if applicable):

sssd-common-1.12.0-7.fc21.x86_64

How reproducible:

Right now it's easily reproducible, but only on one machine.

Steps to Reproduce:
1. realm join --user Bender-admin ad.baseos.qe
2. getent passwd Bender.QE

Actual results:

Crash and no output from getent.

Expected results:

Proper output from getent.