[PATCH 22/37] drm: Reject fbs w/o format info in drm_framebuffer_init()

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Any framebuffer that doesn't have proper format information when
drm_framebuffer_init() is called is a bug. Let's warn and return
an error to avoid oopsing the kernel later due to dereferencing the
NULL fb->format pointer.

Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Suggested-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/drm_framebuffer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index f397565d3c20..892976d974e5 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -631,7 +631,7 @@ int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
 {
 	int ret;
 
-	if (WARN_ON_ONCE(fb->dev != dev))
+	if (WARN_ON_ONCE(fb->dev != dev || !fb->format))
 		return -EINVAL;
 
 	INIT_LIST_HEAD(&fb->filp_head);
-- 
2.7.4