From: Xiubo Li <Li.Xiubo@freescale.com>
Date: Mon, 10 Mar 2014 01:33:58 +0000 (+0800)
Subject: drm/fb-helper: Do the 'max_conn_count' zero check
X-Git-Tag: v3.15-rc1~51^2~50^2~1
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=04cfe97eb11c28848d14ba8c88124da31a9f881c;p=linux.git

drm/fb-helper: Do the 'max_conn_count' zero check

Since we cannot make sure the 'max_conn_count' will always be none
zero from the users, and then if max_conn_count equals to zero, the
kcalloc() will return ZERO_SIZE_PTR, which equals to ((void *)16).

So this patch fix this with just doing the 'max_conn_count' zero check
in the front of drm_fb_helper_init().

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
CC: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index e5208e072ac7..89382dce1d59 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -516,6 +516,9 @@ int drm_fb_helper_init(struct drm_device *dev,
 	struct drm_crtc *crtc;
 	int i;
 
+	if (!max_conn_count)
+		return -EINVAL;
+
 	fb_helper->dev = dev;
 
 	INIT_LIST_HEAD(&fb_helper->kernel_fb_list);