From ba93fcd30f124fb134d7b99eb1c6a719d04163c5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michel=20D=C3=A4nzer?= <mdaenzer@redhat.com>
Date: Fri, 3 May 2024 18:17:41 +0200
Subject: [PATCH] wayland/subsurface: Make sure siblings are actually
 sub-surfaces

Without this check, is_sibling could spuriously return TRUE when neither
surface passed in was actually a sub-surface.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3737>
---
 src/wayland/meta-wayland-subsurface.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/wayland/meta-wayland-subsurface.c b/src/wayland/meta-wayland-subsurface.c
index 4f2ae6df6..acfc7f8b9 100644
--- a/src/wayland/meta-wayland-subsurface.c
+++ b/src/wayland/meta-wayland-subsurface.c
@@ -104,6 +104,7 @@ is_sibling (MetaWaylandSurface *surface,
             MetaWaylandSurface *sibling)
 {
   return surface != sibling &&
+         surface->committed_state.parent &&
          surface->committed_state.parent == sibling->committed_state.parent;
 }