When I try to edit a particular Wi-Fi connection I get a segfault.

(gdb) r
Starting program: /usr/bin/gnome-control-center
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff05ff6c0 (LWP 1746643)]
[New Thread 0x7fffefdfe6c0 (LWP 1746644)]
[New Thread 0x7fffef5fd6c0 (LWP 1746645)]
[Thread 0x7fffef5fd6c0 (LWP 1746645) exited]
[New Thread 0x7fffef5fd6c0 (LWP 1746652)]
[New Thread 0x7fffec8be6c0 (LWP 1746653)]
[New Thread 0x7fffd6bff6c0 (LWP 1746654)]
[New Thread 0x7fffd63fe6c0 (LWP 1746655)]
[Thread 0x7fffd63fe6c0 (LWP 1746655) exited]
[Thread 0x7fffd6bff6c0 (LWP 1746654) exited]
[Thread 0x7fffec8be6c0 (LWP 1746653) exited]
[Thread 0x7fffef5fd6c0 (LWP 1746652) exited]
[New Thread 0x7fffef5fd6c0 (LWP 1746657)]
[New Thread 0x7fffd63fe6c0 (LWP 1746658)]
[New Thread 0x7fffd6bff6c0 (LWP 1746659)]
[New Thread 0x7fffec8be6c0 (LWP 1746660)]
[New Thread 0x7fffedfcf6c0 (LWP 1746661)]
[New Thread 0x7fffed7556c0 (LWP 1746662)]
[New Thread 0x7fffd5bfd6c0 (LWP 1746664)]
[New Thread 0x7fffd53fc6c0 (LWP 1746665)]
[New Thread 0x7fffd4bfb6c0 (LWP 1746669)]
[New Thread 0x7fffc57ff6c0 (LWP 1746670)]
[New Thread 0x7fffc4ffe6c0 (LWP 1746671)]
[New Thread 0x7fffa7fff6c0 (LWP 1746672)]
[New Thread 0x7fffa77fe6c0 (LWP 1746673)]
[New Thread 0x7fffa6ffd6c0 (LWP 1746674)]
[New Thread 0x7fffa67fc6c0 (LWP 1746675)]
[New Thread 0x7fffa5ffb6c0 (LWP 1746676)]
[New Thread 0x7fffa57fa6c0 (LWP 1746677)]
[New Thread 0x7fffa4ff96c0 (LWP 1746681)]
[New Thread 0x7fff87fff6c0 (LWP 1746682)]
[Thread 0x7fffa4ff96c0 (LWP 1746681) exited]
[New Thread 0x7fffa4ff96c0 (LWP 1746683)]
[New Thread 0x7fff877fe6c0 (LWP 1746684)]
[Thread 0x7fff87fff6c0 (LWP 1746682) exited]
[Thread 0x7fffa4ff96c0 (LWP 1746683) exited]
[Thread 0x7fff877fe6c0 (LWP 1746684) exited]
[New Thread 0x7fff877fe6c0 (LWP 1746685)]
[Thread 0x7fff877fe6c0 (LWP 1746685) exited]
[New Thread 0x7fff877fe6c0 (LWP 1746686)]
[Thread 0x7fff877fe6c0 (LWP 1746686) exited]
[Thread 0x7fffc4ffe6c0 (LWP 1746671) exited]
[Thread 0x7fffa67fc6c0 (LWP 1746675) exited]
[Thread 0x7fffa77fe6c0 (LWP 1746673) exited]
[Thread 0x7fffa6ffd6c0 (LWP 1746674) exited]
[Thread 0x7fffa7fff6c0 (LWP 1746672) exited]
[Thread 0x7fffd4bfb6c0 (LWP 1746669) exited]
[Thread 0x7fffd53fc6c0 (LWP 1746665) exited]
[Thread 0x7fffc57ff6c0 (LWP 1746670) exited]
[Thread 0x7fffa5ffb6c0 (LWP 1746676) exited]
[New Thread 0x7fffa5ffb6c0 (LWP 1746725)]
[New Thread 0x7fffc57ff6c0 (LWP 1746726)]
[New Thread 0x7fffd53fc6c0 (LWP 1746727)]
[Thread 0x7fffc57ff6c0 (LWP 1746726) exited]
[Thread 0x7fffd53fc6c0 (LWP 1746727) exited]
[New Thread 0x7fffd53fc6c0 (LWP 1746731)]

(gnome-control-center:1746640): Gtk-CRITICAL **: 15:42:13.238: gtk_file_chooser_set_file: assertion 'GTK_IS_FILE_CHOOSER (chooser)' failed

(gnome-control-center:1746640): Gtk-CRITICAL **: 15:42:13.404: gtk_file_chooser_set_file: assertion 'GTK_IS_FILE_CHOOSER (chooser)' failed
[New Thread 0x7fffc57ff6c0 (LWP 1746733)]
[New Thread 0x7fffd4bfb6c0 (LWP 1746734)]
[New Thread 0x7fffa7fff6c0 (LWP 1746735)]
[New Thread 0x7fffa77fe6c0 (LWP 1746736)]
[New Thread 0x7fffa6ffd6c0 (LWP 1746737)]
[New Thread 0x7fffa67fc6c0 (LWP 1746738)]
[New Thread 0x7fffa4ff96c0 (LWP 1746739)]
[New Thread 0x7fff87fff6c0 (LWP 1746740)]
[New Thread 0x7fff877fe6c0 (LWP 1746750)]
[Thread 0x7fffd4bfb6c0 (LWP 1746734) exited]
[Thread 0x7fffa6ffd6c0 (LWP 1746737) exited]
[Thread 0x7fffa77fe6c0 (LWP 1746736) exited]
[Thread 0x7fff87fff6c0 (LWP 1746740) exited]
[Thread 0x7fffa4ff96c0 (LWP 1746739) exited]
[Thread 0x7fffa67fc6c0 (LWP 1746738) exited]
[Thread 0x7fffed7556c0 (LWP 1746662) exited]
[Thread 0x7fffa7fff6c0 (LWP 1746735) exited]
[Thread 0x7fffd53fc6c0 (LWP 1746731) exited]

(gnome-control-center:1746640): Gtk-WARNING **: 15:42:15.216: A floating object was finalized. This means that someone
called g_object_unref() on an object that had only a floating
reference; the initial floating reference is not owned by anyone
and must be removed with g_object_ref_sink().

(gnome-control-center:1746640): Gtk-WARNING **: 15:42:15.220: A floating object was finalized. This means that someone
called g_object_unref() on an object that had only a floating
reference; the initial floating reference is not owned by anyone
and must be removed with g_object_ref_sink().

(gnome-control-center:1746640): Gtk-WARNING **: 15:42:15.221: A floating object was finalized. This means that someone
called g_object_unref() on an object that had only a floating
reference; the initial floating reference is not owned by anyone
and must be removed with g_object_ref_sink().

(gnome-control-center:1746640): Gtk-WARNING **: 15:42:15.222: A floating object was finalized. This means that someone
called g_object_unref() on an object that had only a floating
reference; the initial floating reference is not owned by anyone
and must be removed with g_object_ref_sink().

(gnome-control-center:1746640): Gtk-WARNING **: 15:42:15.224: A floating object was finalized. This means that someone
called g_object_unref() on an object that had only a floating
reference; the initial floating reference is not owned by anyone
and must be removed with g_object_ref_sink().

(gnome-control-center:1746640): Gtk-WARNING **: 15:42:15.226: A floating object was finalized. This means that someone
called g_object_unref() on an object that had only a floating
reference; the initial floating reference is not owned by anyone
and must be removed with g_object_ref_sink().
[Thread 0x7fffa5ffb6c0 (LWP 1746725) exited]
[New Thread 0x7fffa5ffb6c0 (LWP 1746751)]
[New Thread 0x7fffd53fc6c0 (LWP 1746753)]
[New Thread 0x7fffa7fff6c0 (LWP 1746754)]
[New Thread 0x7fffed7556c0 (LWP 1746755)]
[Thread 0x7fffa7fff6c0 (LWP 1746754) exited]
[Thread 0x7fffed7556c0 (LWP 1746755) exited]
[New Thread 0x7fffed7556c0 (LWP 1746756)]
[New Thread 0x7fffa7fff6c0 (LWP 1746757)]
[Thread 0x7fffed7556c0 (LWP 1746756) exited]
[Thread 0x7fffa7fff6c0 (LWP 1746757) exited]
[New Thread 0x7fffa7fff6c0 (LWP 1746759)]

(gnome-control-center:1746640): Gtk-CRITICAL **: 15:42:31.249: gtk_file_chooser_set_file: assertion 'GTK_IS_FILE_CHOOSER (chooser)' failed
[New Thread 0x7fffed7556c0 (LWP 1746772)]

(gnome-control-center:1746640): Gtk-CRITICAL **: 15:42:31.308: gtk_file_chooser_set_file: assertion 'GTK_IS_FILE_CHOOSER (chooser)' failed

(gnome-control-center:1746640): Gtk-CRITICAL **: 15:42:31.369: gtk_file_chooser_set_file: assertion 'GTK_IS_FILE_CHOOSER (chooser)' failed
[New Thread 0x7fffa77fe6c0 (LWP 1746775)]
[New Thread 0x7fffa6ffd6c0 (LWP 1746776)]
[New Thread 0x7fffa67fc6c0 (LWP 1746777)]
[Thread 0x7fffa6ffd6c0 (LWP 1746776) exited]
[Thread 0x7fffa67fc6c0 (LWP 1746777) exited]
Gtk-Message: 15:42:31.489: GtkDialog mapped without a transient parent. This is discouraged.

Thread 1 "gnome-control-c" received signal SIGSEGV, Segmentation fault.
0x00007ffff7da3774 in g_type_check_instance_cast (type_instance=0x5757575757575757,
    iface_type=93824998173968) at ../../../gobject/gtype.c:4122
4122	../../../gobject/gtype.c: No such file or directory.

(gdb) where
#0  0x00007ffff7da3774 in g_type_check_instance_cast (type_instance=0x5757575757575757,
    iface_type=93824998173968) at ../../../gobject/gtype.c:4122
#1  0x00005555556b3b5f in private_key_picker_helper (self=self@entry=0x555558581f40,
    filename=filename@entry=0x55555a712eb0 "/etc/ssl/private/fragarach-host.key",
    changed=changed@entry=1) at ../panels/network/wireless-security/eap-method-tls.c:252
#2  0x00005555556b3d64 in private_key_picker_file_set_cb (chooser=<optimized out>,
    user_data=0x555558581f40) at ../panels/network/wireless-security/eap-method-tls.c:297
#3  0x00007ffff7d803b0 in g_closure_invoke (closure=0x55555a4f7130,
    return_value=return_value@entry=0x0, n_param_values=2,
    param_values=param_values@entry=0x7fffffffd030,
    invocation_hint=invocation_hint@entry=0x7fffffffcfb0) at ../../../gobject/gclosure.c:832
#4  0x00007ffff7d93076 in signal_emit_unlocked_R (node=node@entry=0x555555898e50,
    detail=detail@entry=1366, instance=instance@entry=0x555559bad4d0,
    emission_return=emission_return@entry=0x0,
    instance_and_params=instance_and_params@entry=0x7fffffffd030) at ../../../gobject/gsignal.c:3796
#5  0x00007ffff7d99bf5 in g_signal_emit_valist (instance=<optimized out>, signal_id=<optimized out>,
    detail=<optimized out>, var_args=var_args@entry=0x7fffffffd1d0) at ../../../gobject/gsignal.c:3549
#6  0x00007ffff7d99dbf in g_signal_emit (instance=instance@entry=0x555559bad4d0,
    signal_id=<optimized out>, detail=<optimized out>) at ../../../gobject/gsignal.c:3606
#7  0x00007ffff7d840f4 in g_object_dispatch_properties_changed (object=0x555559bad4d0,
    n_pspecs=<optimized out>, pspecs=<optimized out>) at ../../../gobject/gobject.c:1428
#8  0x00007ffff7d87027 in g_object_notify_by_spec_internal (pspec=<optimized out>,
    object=0x555559bad4d0) at ../../../gobject/gobject.c:1544
#9  g_object_notify_by_pspec (object=0x555559bad4d0, pspec=<optimized out>)
    at ../../../gobject/gobject.c:1650
#10 0x00005555556b6b40 in ws_file_chooser_button_set_file (file=0x55555a6ea440, self=<optimized out>)
    at ../panels/network/wireless-security/ws-file-chooser-button.c:224
#11 0x00005555556b4674 in update_secrets (method=<optimized out>, connection=<optimized out>)
    at ../panels/network/wireless-security/eap-method-tls.c:384
#12 0x00005555556b4cf0 in eap_method_tls_new (connection=connection@entry=0x555555e52bd0)
    at ../panels/network/wireless-security/eap-method-tls.c:545
#13 0x00005555556ad004 in ws_dynamic_wep_new (connection=0x555555e52bd0)
    at ../panels/network/wireless-security/ws-dynamic-wep.c:219
#14 0x00005555556a8ae9 in finish_setup (self=0x555555cce860)
    at ../panels/network/connection-editor/ce-page-security.c:331
#15 0x00007ffff7d803b0 in g_closure_invoke (closure=0x55555a06d980,
    return_value=return_value@entry=0x0, n_param_values=2,
    param_values=param_values@entry=0x7fffffffd640,
    invocation_hint=invocation_hint@entry=0x7fffffffd5c0) at ../../../gobject/gclosure.c:832
#16 0x00007ffff7d93076 in signal_emit_unlocked_R (node=node@entry=0x5555581520b0,
    detail=detail@entry=0, instance=instance@entry=0x555555cce860,
    emission_return=emission_return@entry=0x0,
    instance_and_params=instance_and_params@entry=0x7fffffffd640) at ../../../gobject/gsignal.c:3796
#17 0x00007ffff7d99bf5 in g_signal_emit_valist (instance=<optimized out>, signal_id=<optimized out>,
    detail=<optimized out>, var_args=var_args@entry=0x7fffffffd7e0) at ../../../gobject/gsignal.c:3549
#18 0x00007ffff7d99dbf in g_signal_emit (instance=instance@entry=0x555555cce860,
    signal_id=<optimized out>, detail=detail@entry=0) at ../../../gobject/gsignal.c:3606
#19 0x000055555569d79c in emit_initialized (error=0x0, self=0x555555cce860)
    at ../panels/network/connection-editor/ce-page.c:100
#20 ce_page_complete_init (self=0x555555cce860, connection=0x555555e52bd0,
    setting_name=0x5555556fb1b1 "802-1x", secrets=secrets@entry=0x555559adf200, error=<optimized out>)
    at ../panels/network/connection-editor/ce-page.c:150
#21 0x000055555569e822 in get_secrets_cb (source_object=0x7fffb80a3c70, res=<optimized out>,
    user_data=0x55555a0831b0) at /usr/include/glib-2.0/glib/gmem.h:226
#22 0x00007ffff7e78c93 in g_task_return_now (task=task@entry=0x55555847b6f0)
    at ../../../gio/gtask.c:1232
#23 0x00007ffff7e78cc9 in complete_in_idle_cb (task=0x55555847b6f0) at ../../../gio/gtask.c:1246
#24 0x00007ffff7c8667f in g_main_dispatch (context=0x5555558a4f00) at ../../../glib/gmain.c:3454
#25 g_main_context_dispatch (context=context@entry=0x5555558a4f00) at ../../../glib/gmain.c:4172
#26 0x00007ffff7c86a38 in g_main_context_iterate (context=context@entry=0x5555558a4f00,
    block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../../../glib/gmain.c:4248
#27 0x00007ffff7c86acc in g_main_context_iteration (context=context@entry=0x5555558a4f00,
    may_block=may_block@entry=1) at ../../../glib/gmain.c:4313
#28 0x00007ffff7ea665d in g_application_run (application=0x5555558a0110, argc=argc@entry=1,
    argv=argv@entry=0x7fffffffdbe8) at ../../../gio/gapplication.c:2573
#29 0x00005555555b2e41 in main (argc=1, argv=0x7fffffffdbe8) at ../shell/main.c:60