Dock crash may crash Gala

[lenemter]

What Happened?

When using elementary/dock#361 dock may crash and for some reason gala crashes as well

Steps to Reproduce

1. Install Workspace switcher dock#361
2. Open file chooser portal through ASHPD Demo
3. Dock crashes
4. Gala crashes

Expected Behavior

Dock crash shouldn't affect Gala

OS Version

8.x (Circe)

Session Type

Secure Session (Wayland)

Software Version

Compiled from git

Log Output

Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007972ea16c48d in meta_window_get_display (window=0x0) at ../src/core/window.c:6554
6554	  return window->display;
[Current thread is 1 (Thread 0x7972e7c19fc0 (LWP 9433))]
(gdb) bt
#0  0x00007972ea16c48d in meta_window_get_display (window=0x0) at ../src/core/window.c:6554
#1  0x00007972ea15e431 in backend_from_window (window=0x0) at ../src/core/window.c:246
#2  0x00007972ea16d90a in window_has_pointer_wayland (window=0x0) at ../src/core/window.c:7395
#3  0x00007972ea16d9b2 in meta_window_has_pointer (window=0x0) at ../src/core/window.c:7406
#4  0x00005b03d849f341 in _gala_hide_tracker___lambda79_ (self=0x5b040bfa17c0) at ../src/ShellClients/HideTracker.vala:69
#5  0x00005b03d849f391 in __gala_hide_tracker___lambda79__meta_cursor_tracker_position_invalidated (_sender=0x5b040adcd260, self=0x5b040bfa17c0)
    at ../src/ShellClients/HideTracker.vala:67
#6  0x00007972ea9d36bd in ??? () at /lib/x86_64-linux-gnu/libgobject-2.0.so.0
#7  0x00007972ea9d37c1 in g_signal_emit_valist () at /lib/x86_64-linux-gnu/libgobject-2.0.so.0
#8  0x00007972ea9d3883 in g_signal_emit () at /lib/x86_64-linux-gnu/libgobject-2.0.so.0
#9  0x00007972ea0cb12a in meta_cursor_tracker_invalidate_position (tracker=0x5b040adcd260) at ../src/backends/meta-cursor-tracker.c:460
#10 0x00007972ea13828b in meta_display_handle_event (display=0x5b040ae1f3d0, event=0x7972680029a0, event_actor=0x5b040bf91bb0)
    at ../src/core/events.c:355
#11 0x00007972ea138651 in event_callback (event=0x7972680029a0, event_actor=0x5b040bf91bb0, data=0x5b040ae1f3d0) at ../src/core/events.c:485
#12 0x00007972e9f350bf in _clutter_event_process_filters (event=0x7972680029a0, event_actor=0x5b040bf91bb0)
    at ../clutter/clutter/clutter-event.c:1302
#13 0x00007972e9f5cc36 in clutter_stage_handle_event (stage=0x5b040af24450, event=0x7972680029a0) at ../clutter/clutter/clutter-main.c:530
#14 0x00007972ea0ba364 in dispatch_clutter_event (backend=0x5b040aa70de0) at ../src/backends/meta-backend.c:1137
#15 0x00007972ea0ba449 in clutter_source_dispatch (source=0x5b040ad12f70, callback=0x0, user_data=0x0) at ../src/backends/meta-backend.c:1181
#16 0x00007972eaa5e5b5 in ??? () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#17 0x00007972eaabd717 in ??? () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#18 0x00007972eaa5ef77 in g_main_loop_run () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007972ea145341 in meta_context_run_main_loop (context=0x5b040aa62400, error=0x7ffc2fe5b7f0) at ../src/core/meta-context.c:554
#20 0x00005b03d84377ed in gala_main (args=0x7ffc2fe5be48, args_length1=1) at ../src/Main.vala:88
#21 0x00005b03d84379d8 in main (argc=1, argv=0x7ffc2fe5be48) at ../src/Main.vala:29
(gdb)

Hardware Info

No response

[leolost2605]

Is there currently a way to consistently reproduce this? Can you tell me the dock and or #2265 commit where this happened?
Because while we can easily prevent this with a null guard, I'd like to do a bit more investigation since how I read the code this shouldn't happen but I'm obviously missing something...

[lenemter]

Found a reliable way to reproduce this:

1. Open a workspace with a terminal window with it
2. Place the window in a way that hides the dock
3. Trigger the dock using barrier
4. While animating execute killall io.elementary.dock in opened terminal window