Created attachment 1357407 [details]
File: backtrace

Created attachment 1357408 [details]
File: cgroup

Created attachment 1357409 [details]
File: core_backtrace

Created attachment 1357410 [details]
File: cpuinfo

Created attachment 1357411 [details]
File: dso_list

Created attachment 1357412 [details]
File: environ

Created attachment 1357413 [details]
File: exploitable

Created attachment 1357414 [details]
File: limits

Created attachment 1357415 [details]
File: maps

Created attachment 1357416 [details]
File: open_fds

Created attachment 1357417 [details]
File: proc_pid_status

Created attachment 1357418 [details]
File: var_log_messages

Thanks for the report. Is there any chance you could also upload the coredump somewhere? Thanks!

Created attachment 1357517 [details]
coredump gzipped

coredump file

I am reassigning this to GLib. Maybe udisks2 is doing something wrong, but it more looks like some issue in GLib itself. This is the relevant chunk from the backtrace:

Thread 1 (Thread 0x7f6d87dcf900 (LWP 1405)):
#0  0x00007f6d865794a5 in g_mutex_lock (mutex=mutex@entry=0x2020202020202020) at gthread-posix.c:1336
        _g_boolean_var_ = <optimized out>
#1  0x00007f6d86532478 in g_source_destroy_internal (source=0x560b174d0210, context=0x2020202020202020, have_lock=0) at gmain.c:1236
No locals.
#2  0x0000560b159a20b4 in main (argc=<optimized out>, argv=<optimized out>) at main.c:182
        error = 0x0
        opt_context = 0x560b174cff70
        ret = 0
        name_owner_id = 1
        sigint_source = 0x560b174d0210
        __func__ = "main"


and it happens after the following actions:

      guint sigint_id = g_unix_signal_add_full (G_PRIORITY_DEFAULT,
                                          SIGINT,
                                          on_sigint,
                                          NULL,  /* user_data */
                                          NULL); /* GDestroyNotify */
      if (sigint_id)
        sigint_source = g_main_context_find_source_by_id (NULL, sigint_id); 
      ...
      g_main_loop_run (loop);
      ...
      g_main_loop_quit (loop);  /* in the on_sigint() SIGINT handler */
      ...
      if (sigint_source)
        {
          if(! g_source_is_destroyed(sigint_source))
            {
182:          g_source_destroy (sigint_source);
            }
        }

The above looks to me like a correct code. But I'm no GLib expert so I have no idea when the default context is created and/or destroyed. However, the context's address 0x2020202020202020 looks really suspicious.

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