commit e2bfaf0751 does this:
g_hash_table_insert (cards,
g_udev_device_get_name (parent_device),
g_steal_pointer (&parent_device));
The problem is the g_steal_pointer call may happen before the
g_udev_device_get_name call leading to a crash.
This commit does the get_name call on an earlier line
https://bugzilla.gnome.org/show_bug.cgi?id=771442