From 805c899589001c443f20414319a2dc29b60c3c3f Mon Sep 17 00:00:00 2001
From: Vlad Zahorodnii <vlad.zahorodnii@kde.org>
Date: Sun, 7 May 2023 16:24:05 +0300
Subject: [PATCH] wayland: Validate serial of wl_pointer.set_cursor

---
 src/wayland/pointer_interface.cpp | 4 ++++
 src/wayland/pointer_interface_p.h | 1 +
 2 files changed, 5 insertions(+)

diff --git a/src/wayland/pointer_interface.cpp b/src/wayland/pointer_interface.cpp
index 7bc394e4c6..7312f28183 100644
--- a/src/wayland/pointer_interface.cpp
+++ b/src/wayland/pointer_interface.cpp
@@ -62,6 +62,9 @@ void PointerInterfacePrivate::pointer_set_cursor(Resource *resource, uint32_t se
         qCDebug(KWIN_CORE, "Denied set_cursor request from unfocused client");
         return;
     }
+    if (focusedSerial != serial) {
+        return;
+    }
 
     if (surface_resource) {
         surface = SurfaceInterface::get(surface_resource);
@@ -159,6 +162,7 @@ void PointerInterface::sendEnter(SurfaceInterface *surface, const QPointF &posit
     }
 
     d->focusedSurface = surface;
+    d->focusedSerial = serial;
     d->destroyConnection = connect(d->focusedSurface, &SurfaceInterface::aboutToBeDestroyed, this, [this]() {
         d->sendLeave(d->seat->display()->nextSerial());
         d->sendFrame();
diff --git a/src/wayland/pointer_interface_p.h b/src/wayland/pointer_interface_p.h
index 8817a88e7e..c7783d3ce5 100644
--- a/src/wayland/pointer_interface_p.h
+++ b/src/wayland/pointer_interface_p.h
@@ -36,6 +36,7 @@ public:
     PointerInterface *q;
     SeatInterface *seat;
     SurfaceInterface *focusedSurface = nullptr;
+    quint32 focusedSerial = 0;
     QMetaObject::Connection destroyConnection;
     std::unique_ptr<Cursor> cursor;
     std::unique_ptr<RelativePointerV1Interface> relativePointersV1;