5 files changed, 23 insertions, 4 deletions
diff --git a/src/compositor/extensions/qwaylandxdgdecorationv1.cpp b/src/compositor/extensions/qwaylandxdgdecorationv1.cpp
index cea8cfe18..6ece73b8e 100644
--- a/src/compositor/extensions/qwaylandxdgdecorationv1.cpp
+++ b/src/compositor/extensions/qwaylandxdgdecorationv1.cpp
@@ -192,10 +192,15 @@ QWaylandXdgToplevelDecorationV1::QWaylandXdgToplevelDecorationV1(QWaylandXdgTopl
     Q_ASSERT(toplevel);
     auto *toplevelPrivate = QWaylandXdgToplevelPrivate::get(toplevel);
     Q_ASSERT(!toplevelPrivate->m_decoration);
-    toplevelPrivate->m_decoration.reset(this);
+    toplevelPrivate->m_decoration = this;
     sendConfigure(manager->preferredMode());
 }
 
+QWaylandXdgToplevelDecorationV1::~QWaylandXdgToplevelDecorationV1()
+{
+    QWaylandXdgToplevelPrivate::get(m_toplevel)->m_decoration = nullptr;
+}
+
 void QWaylandXdgToplevelDecorationV1::sendConfigure(QWaylandXdgToplevelDecorationV1::DecorationMode mode)
 {
     if (configuredMode() == mode)
@@ -220,8 +225,7 @@ void QWaylandXdgToplevelDecorationV1::sendConfigure(QWaylandXdgToplevelDecoratio
 void QWaylandXdgToplevelDecorationV1::zxdg_toplevel_decoration_v1_destroy_resource(Resource *resource)
 {
     Q_UNUSED(resource);
-    auto *toplevelPrivate = QWaylandXdgToplevelPrivate::get(m_toplevel);
-    toplevelPrivate->m_decoration.reset();
+    delete this;
 }
 
 void QWaylandXdgToplevelDecorationV1::zxdg_toplevel_decoration_v1_destroy(Resource *resource)
diff --git a/src/compositor/extensions/qwaylandxdgdecorationv1_p.h b/src/compositor/extensions/qwaylandxdgdecorationv1_p.h
index 4c6c46334..3d181a919 100644
--- a/src/compositor/extensions/qwaylandxdgdecorationv1_p.h
+++ b/src/compositor/extensions/qwaylandxdgdecorationv1_p.h
@@ -83,6 +83,7 @@ public:
     explicit QWaylandXdgToplevelDecorationV1(QWaylandXdgToplevel *toplevel,
                                              QWaylandXdgDecorationManagerV1 *manager,
                                              wl_client *client, int id);
+    ~QWaylandXdgToplevelDecorationV1() override;
 
     DecorationMode configuredMode() const { return m_configuredMode; }
     void sendConfigure(DecorationMode mode);
diff --git a/src/compositor/extensions/qwaylandxdgshell.cpp b/src/compositor/extensions/qwaylandxdgshell.cpp
index eaa443e87..ce6add3de 100644
--- a/src/compositor/extensions/qwaylandxdgshell.cpp
+++ b/src/compositor/extensions/qwaylandxdgshell.cpp
@@ -731,6 +731,16 @@ QWaylandXdgToplevel::QWaylandXdgToplevel(QWaylandXdgSurface *xdgSurface, QWaylan
     sendConfigure({0, 0}, states);
 }
 
+QWaylandXdgToplevel::~QWaylandXdgToplevel()
+{
+    Q_D(QWaylandXdgToplevel);
+    // Usually, the decoration is destroyed by the client (according to the protocol),
+    // but if the client misbehaves, or is shut down, we need to clean up here.
+    if (Q_UNLIKELY(d->m_decoration))
+        wl_resource_destroy(d->m_decoration->resource()->handle);
+    Q_ASSERT(!d->m_decoration);
+}
+
 /*!
  * \qmlproperty XdgToplevel QtWaylandCompositor::XdgToplevel::parentToplevel
  *
@@ -1331,6 +1341,9 @@ void QWaylandXdgToplevelPrivate::xdg_toplevel_destroy_resource(QtWaylandServer::
 
 void QWaylandXdgToplevelPrivate::xdg_toplevel_destroy(QtWaylandServer::xdg_toplevel::Resource *resource)
 {
+    if (Q_UNLIKELY(m_decoration))
+        qWarning() << "Client error: xdg_toplevel destroyed before its decoration object";
+
     wl_resource_destroy(resource->handle);
     //TODO: Should the xdg surface be desroyed as well? Or is it allowed to recreate a new toplevel for it?
 }
diff --git a/src/compositor/extensions/qwaylandxdgshell.h b/src/compositor/extensions/qwaylandxdgshell.h
index 2b6f63564..aec6193a7 100644
--- a/src/compositor/extensions/qwaylandxdgshell.h
+++ b/src/compositor/extensions/qwaylandxdgshell.h
@@ -170,6 +170,7 @@ public:
     Q_ENUM(DecorationMode)
 
     explicit QWaylandXdgToplevel(QWaylandXdgSurface *xdgSurface, QWaylandResource &resource);
+    ~QWaylandXdgToplevel() override;
 
     QWaylandXdgToplevel *parentToplevel() const;
 
diff --git a/src/compositor/extensions/qwaylandxdgshell_p.h b/src/compositor/extensions/qwaylandxdgshell_p.h
index e87bb17f0..5ef8bde3d 100644
--- a/src/compositor/extensions/qwaylandxdgshell_p.h
+++ b/src/compositor/extensions/qwaylandxdgshell_p.h
@@ -178,7 +178,7 @@ public:
     QString m_appId;
     QSize m_maxSize;
     QSize m_minSize = {0, 0};
-    QScopedPointer<QWaylandXdgToplevelDecorationV1> m_decoration;
+    QWaylandXdgToplevelDecorationV1 *m_decoration = nullptr;
 
     static QWaylandSurfaceRole s_role;
 };