compositor: Fix crash when accessing null pointer

This patch adds a null check before accessing the return value of
ds_subsurface_from_surface().

The return value of ds_subsurface_from_surface() can be null even though
the ds_surface_is_subsurface() returns true. That's the case when the
subsurface has been destroyed.

Change-Id: I40fd3910cd980d31823e8ba8fe3f4210fc52b515

diff --git a/src/bin/e_compositor.c b/src/bin/e_compositor.c
index 6ae74fd..1b05ee0 100644 (file)
--- a/src/bin/e_compositor.c
+++ b/src/bin/e_compositor.c
@@ -1105,11 +1105,13 @@ _e_subsurface_from_ds_subsurface(struct ds_subsurface *ds_subsurface)
 static E_Subsurface *
 _e_subsurface_from_surface(E_Surface *surface)
 {
-   if (!ds_surface_is_subsurface(surface->ds_surface))
+   struct ds_surface *ds_subsurface;
+
+   ds_subsurface = ds_subsurface_from_surface(surface->ds_surface);
+   if (!ds_subsurface)
      return NULL;
 
-   return _e_subsurface_from_ds_subsurface(
-      ds_subsurface_from_surface(surface->ds_surface));
+   return _e_subsurface_from_ds_subsurface(ds_subsurface);
 }
 
 static E_Subsurface *