From: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Tue, 26 Jul 2016 16:06:56 +0000 (+0300)
Subject: drm: Warn about negative sizes when calculating scale factor
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1e1a5f8f8c3a4b24b3fc0340880cf1e3949f4997;p=linux-beck.git

drm: Warn about negative sizes when calculating scale factor

Passing negative width/hight to scale factor calculations is not
legal. Let's WARN if that happens.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1469549224-1860-2-git-send-email-ville.syrjala@linux.intel.com
---

diff --git a/drivers/gpu/drm/drm_rect.c b/drivers/gpu/drm/drm_rect.c
index 4063f6e4ea9f..73e53a8d1b37 100644
--- a/drivers/gpu/drm/drm_rect.c
+++ b/drivers/gpu/drm/drm_rect.c
@@ -100,7 +100,7 @@ static int drm_calc_scale(int src, int dst)
 {
 	int scale = 0;
 
-	if (src < 0 || dst < 0)
+	if (WARN_ON(src < 0 || dst < 0))
 		return -EINVAL;
 
 	if (dst == 0)