[PATCH 4.7 24/59] drm/vc4: Fix oops when userspace hands in a bad BO.

[Greg Kroah-Hartman]

4.7-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Anholt <eric@xxxxxxxxxx>

commit 552416c146fadc67cd9b53ef7adf88d3381c43a6 upstream.

We'd end up NULL pointer dereferencing because we didn't take the
error path out in the parent.  Fixes igt vc4_lookup_fail test.

Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
Fixes: d5b1a78a772f ("drm/vc4: Add support for drawing 3D frames.")
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/gpu/drm/vc4/vc4_gem.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/vc4/vc4_gem.c
+++ b/drivers/gpu/drm/vc4/vc4_gem.c
@@ -575,7 +575,7 @@ vc4_cl_lookup_bos(struct drm_device *dev
 
 fail:
 	drm_free_large(handles);
-	return 0;
+	return ret;
 }
 
 static int