diff --git a/src/wayland/surface_interface.cpp b/src/wayland/surface_interface.cpp
index a3d8b0ac14..081d901889 100644
--- a/src/wayland/surface_interface.cpp
+++ b/src/wayland/surface_interface.cpp
@@ -720,7 +720,7 @@ OutputInterface::Transform SurfaceInterface::bufferTransform() const
     return d->current.bufferTransform;
 }
 
-ClientBuffer *SurfaceInterface::buffer()
+ClientBuffer *SurfaceInterface::buffer() const
 {
     return d->bufferRef;
 }
diff --git a/src/wayland/surface_interface.h b/src/wayland/surface_interface.h
index 75603fd00d..ed9743bc8d 100644
--- a/src/wayland/surface_interface.h
+++ b/src/wayland/surface_interface.h
@@ -178,7 +178,7 @@ public:
     /**
      * @returns the current ClientBuffer, might be @c nullptr.
      */
-    ClientBuffer *buffer();
+    ClientBuffer *buffer() const;
     QPoint offset() const;
     /**
      * Returns the current size of the surface, in surface coordinates.