[cairo-commit] src/cairo-image-surface-inline.h

[Chris Wilson]

 src/cairo-image-surface-inline.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

New commits:
commit 558f0a5ab4a88937b8c212c13309d11cb1a101af
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Sat Sep 8 15:12:58 2012 +0100

    image: Check for an error surface before dereferencing the backend
    
    As the surface->backend will be NULL in such an error surface, and we
    may be legitimately doing boundary checks to reject the error surface.
    The alternative would be to set an explicit error surface backend.
    
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=54664
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

diff --git a/src/cairo-image-surface-inline.h b/src/cairo-image-surface-inline.h
index 4959107..743d5fd 100644
--- a/src/cairo-image-surface-inline.h
+++ b/src/cairo-image-surface-inline.h
@@ -73,7 +73,8 @@ _cairo_image_surface_is_clone (cairo_image_surface_t *image)
 static inline cairo_bool_t
 _cairo_surface_is_image (const cairo_surface_t *surface)
 {
-    return surface->backend->type == CAIRO_SURFACE_TYPE_IMAGE;
+    /* _cairo_surface_nil sets a NULL backend so be safe */
+    return surface->backend && surface->backend->type == CAIRO_SURFACE_TYPE_IMAGE;
 }
 
 /**