relative_pointer: handle inert pointer objects

Since 5e0ef70cc0 ("seat: Create inert objects for missing capabilities")
wlroots can create inert seat objects when the capability is currently missing
for the client but it had the capablity before. The client hoever will happily
handover the wl_pointer resource to the relative_pointer implementation,
creating a NULL pointer dereference when trying to access the seat_client which
is set to NULL for inert objects.

Since the protocol does not contain an error for such requests, we hand out an
relative_pointer handle with the seat set to NULL.
We also need to check whether there is an associated seat in
send_relative_motion and need to tweak the destroy notifier in case no seat is
available.

This way we can hand out a valid relative_pointer resource and don't crash the
compositor when trying to access an inert seat pointer resource in
relative_pointer.

Relevant WAYLAND_DEBUG=1 when testing a client and switching VT every second:
[2619872.442] wl_seat@30.capabilities(3)
[2619872.460]  -> wl_seat@30.get_pointer(new id wl_pointer@36)
[2619872.484] wl_data_device@25.selection(nil)
[2619872.504] zwp_primary_selection_device_v1@26.selection(nil)
[2619874.995] wl_seat@12.capabilities(3)
[2619875.035]  -> wl_compositor@5.create_surface(new id wl_surface@37)
[2619875.088]  -> wl_seat@12.get_pointer(new id wl_pointer@29)
[2619875.105]  -> zwp_relative_pointer_manager_v1@8.get_relative_pointer(new id zwp_relative_pointer_v1@27, wl_pointer@29)
[2619875.127]  -> wl_compositor@5.create_surface(new id wl_surface@35)
[2619875.139]  -> wl_seat@12.get_pointer(new id wl_pointer@43)
[2619981.180] wl_seat@12.capabilities(2)
[2619981.214]  -> zwp_relative_pointer_v1@27.destroy()
[2619981.226]  -> wl_pointer@29.release()
[2619981.236]  -> wl_surface@37.destroy()
[2619981.247]  -> wl_pointer@43.release()
[2619981.254]  -> wl_surface@35.destroy()
[2619981.262] wl_seat@12.capabilities(0)
[2619981.285]  -> wl_keyboard@33.release()
[2619987.316] wl_seat@30.capabilities(2)
[2619987.336]  -> wl_pointer@36.release()
[2619987.363] wl_seat@30.capabilities(0)
[2619987.371]  -> wl_keyboard@34.release()
[2621932.880] wl_display@1.delete_id(41)
[2621932.903] wl_display@1.delete_id(40)
[2621932.910] wl_display@1.delete_id(27)
[2621932.917] wl_display@1.delete_id(29)
[2621932.924] wl_display@1.delete_id(37)
[2621932.930] wl_display@1.delete_id(43)
[2621932.944] wl_display@1.delete_id(35)
[2621932.950] wl_display@1.delete_id(33)
[2621932.959] wl_seat@12.capabilities(2)
[2621932.976]  -> wl_seat@12.get_keyboard(new id wl_keyboard@33)
[2621936.875] wl_seat@12.capabilities(3)
[2621936.893]  -> wl_compositor@5.create_surface(new id wl_surface@35)
[2621936.931]  -> wl_seat@12.get_pointer(new id wl_pointer@43)
[2621936.945]  -> zwp_relative_pointer_manager_v1@8.get_relative_pointer(new id zwp_relative_pointer_v1@37, wl_pointer@43)
[2621936.965]  -> wl_compositor@5.create_surface(new id wl_surface@29)
[2621936.987]  -> wl_seat@12.get_pointer(new id wl_pointer@27)
[2621942.796] wl_data_device@25.selection(nil)
[2621942.817] zwp_primary_selection_device_v1@26.selection(nil)
[2621942.823] wl_seat@30.capabilities(2)
This commit is contained in:
Rouven Czerwinski 2022-05-27 20:47:34 +02:00 committed by Simon Ser
parent bb2946f737
commit 988fe5bda9
1 changed files with 10 additions and 6 deletions

View File

@ -117,9 +117,17 @@ static void relative_pointer_manager_v1_handle_get_relative_pointer(struct wl_cl
}
relative_pointer->resource = relative_pointer_resource;
relative_pointer->seat = seat_client->seat;
relative_pointer->pointer_resource = pointer;
if (seat_client) {
relative_pointer->seat = seat_client->seat;
wl_signal_add(&relative_pointer->seat->events.destroy,
&relative_pointer->seat_destroy);
relative_pointer->seat_destroy.notify = relative_pointer_handle_seat_destroy;
} else {
wl_list_init(&relative_pointer->seat_destroy.link);
}
wl_signal_init(&relative_pointer->events.destroy);
wl_resource_set_implementation(relative_pointer_resource, &relative_pointer_v1_impl,
@ -131,10 +139,6 @@ static void relative_pointer_manager_v1_handle_get_relative_pointer(struct wl_cl
wl_list_insert(&manager->relative_pointers,
&relative_pointer->link);
wl_signal_add(&relative_pointer->seat->events.destroy,
&relative_pointer->seat_destroy);
relative_pointer->seat_destroy.notify = relative_pointer_handle_seat_destroy;
wl_resource_add_destroy_listener(relative_pointer->pointer_resource,
&relative_pointer->pointer_destroy);
relative_pointer->pointer_destroy.notify = relative_pointer_handle_pointer_destroy;
@ -230,7 +234,7 @@ void wlr_relative_pointer_manager_v1_send_relative_motion(
wl_list_for_each(pointer, &manager->relative_pointers, link) {
struct wlr_seat_client *seat_client =
wlr_seat_client_from_pointer_resource(pointer->pointer_resource);
if (seat != pointer->seat || focused != seat_client) {
if (!pointer->seat || seat != pointer->seat || focused != seat_client) {
continue;
}