From d6706c5ce4f82530134848b78be9420cf99dae66 Mon Sep 17 00:00:00 2001
From: Vlad Zahorodnii <vlad.zahorodnii@kde.org>
Date: Tue, 30 Aug 2022 12:56:23 +0300
Subject: [PATCH] wayland: Prevent sending xdg_output properties if wl_output
 is removed

If the wl_output has been removed, kwin can crash all Qt clients by
sending a wl_output.done event. Also, it makes no sense to send output
events after the corresponding output has been removed.

CCBUG: 451028
---
 src/wayland/output_interface.cpp       |  5 +++++
 src/wayland/output_interface.h         |  1 +
 src/wayland/xdgoutput_v1_interface.cpp | 14 ++++++++------
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/src/wayland/output_interface.cpp b/src/wayland/output_interface.cpp
index 64ca49a48c..9f06d37814 100644
--- a/src/wayland/output_interface.cpp
+++ b/src/wayland/output_interface.cpp
@@ -184,6 +184,11 @@ KWin::Output *OutputInterface::handle() const
     return d->handle;
 }
 
+bool OutputInterface::isRemoved() const
+{
+    return d->isGlobalRemoved();
+}
+
 void OutputInterface::remove()
 {
     if (d->isGlobalRemoved()) {
diff --git a/src/wayland/output_interface.h b/src/wayland/output_interface.h
index 8a5a58d13f..95f1c7b261 100644
--- a/src/wayland/output_interface.h
+++ b/src/wayland/output_interface.h
@@ -51,6 +51,7 @@ public:
     explicit OutputInterface(Display *display, KWin::Output *handle, QObject *parent = nullptr);
     ~OutputInterface() override;
 
+    bool isRemoved() const;
     void remove();
 
     KWin::Output *handle() const;
diff --git a/src/wayland/xdgoutput_v1_interface.cpp b/src/wayland/xdgoutput_v1_interface.cpp
index 2620782715..23e0eb2aa4 100644
--- a/src/wayland/xdgoutput_v1_interface.cpp
+++ b/src/wayland/xdgoutput_v1_interface.cpp
@@ -195,6 +195,10 @@ void XdgOutputV1InterfacePrivate::zxdg_output_v1_destroy(Resource *resource)
 
 void XdgOutputV1InterfacePrivate::zxdg_output_v1_bind_resource(Resource *resource)
 {
+    if (!output || output->isRemoved()) {
+        return;
+    }
+
     sendLogicalPosition(resource, pos);
     sendLogicalSize(resource, size);
     if (resource->version() >= ZXDG_OUTPUT_V1_NAME_SINCE_VERSION) {
@@ -212,7 +216,7 @@ void XdgOutputV1InterfacePrivate::zxdg_output_v1_bind_resource(Resource *resourc
 
 void XdgOutputV1InterfacePrivate::sendLogicalSize(Resource *resource, const QSize &size)
 {
-    if (!output) {
+    if (!output || output->isRemoved()) {
         return;
     }
     ClientConnection *connection = output->display()->getConnection(resource->client());
@@ -223,7 +227,7 @@ void XdgOutputV1InterfacePrivate::sendLogicalSize(Resource *resource, const QSiz
 
 void XdgOutputV1InterfacePrivate::sendLogicalPosition(Resource *resource, const QPoint &pos)
 {
-    if (!output) {
+    if (!output || output->isRemoved()) {
         return;
     }
     ClientConnection *connection = output->display()->getConnection(resource->client());
@@ -234,14 +238,12 @@ void XdgOutputV1InterfacePrivate::sendLogicalPosition(Resource *resource, const
 
 void XdgOutputV1InterfacePrivate::sendDone(Resource *resource)
 {
-    if (!doneOnce) {
+    if (!doneOnce || !output || output->isRemoved()) {
         return;
     }
 
     if (wl_resource_get_version(resource->handle) >= 3) {
-        if (output) {
-            output->done(resource->client());
-        }
+        output->done(resource->client());
     } else {
         send_done(resource->handle);
     }