When a VPN connection can't be activated we have to unexport and
dispose it. Commit f2182fbf9b ("core: don't emit double
PropertiesChanged signal for new active connections") removed the call
to nm_exported_object_unexport() in case of failure because the active
connection already gets unreferenced on failure.
However, an exported object can't be disposed until it's explicitly
unexported because GDBus code keeps a reference to it. The result was
that the active connection was kept alive and exported, but without
explicit references to it. As soon as the connection was unexported,
it was also automatically disposed, causing issues like:
(src/nm-exported-object.c:1025):dispose: code should not be reached
#0 _g_log_abort () at /lib64/libglib-2.0.so.0
#1 g_logv () at /lib64/libglib-2.0.so.0
#2 g_log () at /lib64/libglib-2.0.so.0
#3 g_warn_message () at /lib64/libglib-2.0.so.0
#4 dispose (object=0xaaf110) at src/nm-exported-object.c:1025
#5 dispose (object=0xaaf110) at src/nm-active-connection.c:1246
#6 dispose (object=0xaaf110) at src/vpn/nm-vpn-connection.c:2642
#7 g_object_unref () at /lib64/libgobject-2.0.so.0
#8 registration_data_free () at /lib64/libgio-2.0.so.0
#9 g_hash_table_remove_internal () at /lib64/libglib-2.0.so.0
#10 g_dbus_object_manager_server_unexport_unlocked () at /lib64/libgio-2.0.so.0
#11 g_dbus_object_manager_server_unexport () at /lib64/libgio-2.0.so.0
#12 nm_bus_manager_unregister_object (self=0x9069e0, object=object@entry=0xaaf110) at src/nm-bus-manager.c:858
#13 nm_exported_object_unexport (self=0xaaf110) at src/nm-exported-object.c:714
#14 _settings_connection_removed (connection=<optimized out>, user_data=0xaaf110) at src/nm-active-connection.c:184
#15 g_closure_invoke () at /lib64/libgobject-2.0.so.0
#16 signal_emit_unlocked_R () at /lib64/libgobject-2.0.so.0
#17 g_signal_emit_valist () at /lib64/libgobject-2.0.so.0
#18 g_signal_emit_by_name () at /lib64/libgobject-2.0.so.0
#19 nm_settings_connection_signal_remove (self=self@entry=0x9e4a80, allow_reuse=allow_reuse@entry=0) at src/settings/nm-settings-connection.c:2085
#20 do_delete (self=0x9e4a80, callback=0x58106a <con_delete_cb>, user_data=0xa84fa0) at src/settings/nm-settings-connection.c:768
#21 do_delete (connection=0x9e4a80, callback=0x58106a <con_delete_cb>, user_data=0xa84fa0) at src/settings/plugins/keyfile/nms-keyfile-connection.c:127
#22 nm_settings_connection_delete (self=self@entry=0x9e4a80, callback=callback@entry=0x58106a <con_delete_cb>, user_data=0xa84fa0) at src/settings/nm-settings-connection.c:694
#23 delete_auth_cb (self=self@entry=0x9e4a80, context=context@entry=0x7fffd80131e0, subject=0x91fb40, error=<optimized out>, data=data@entry=0x0) at src/settings/nm-settings-connection.c:1879
#24 pk_auth_cb (chain=0x7fffd00024a0, chain_error=<optimized out>, context=0x7fffd80131e0, user_data=<optimized out>) at src/settings/nm-settings-connection.c:1351
#25 auth_chain_finish (user_data=0x7fffd00024a0) at src/nm-auth-utils.c:92
#26 g_idle_dispatch () at /lib64/libglib-2.0.so.0
Restore the unexport upon failure to fix this.
Fixes: f2182fbf9bhttps://bugzilla.redhat.com/show_bug.cgi?id=1440077