robin: security: patch for CVE-2016-4482

Subject: [PATCH] USB: usbfs: fix potential infoleak in devio

The stack object "ci" has a total size of 8 bytes. Its last 3 bytes
are padding bytes which are not initialized and leaked to userland
via "copy_to_user".

Change-Id: I0e72b4f00bf253d472bfce2660e5370de99d0018
Reviewed-on: http://mcrd1-22-pc.corpnet.asus/code-review/master/249847


Reviewed-by: Steven Syu <steven_syu@asus.com>
Tested-by: Steven Syu <steven_syu@asus.com>
Reviewed-by: Carol_Jiang <carol_jiang@asus.com>

drivers/usb/core/devio.c

@@ -1105,10 +1105,11 @@ static int proc_getdriver(struct dev_state *ps, void __user *arg)
 
 static int proc_connectinfo(struct dev_state *ps, void __user *arg)
 {
-	struct usbdevfs_connectinfo ci = {
-		.devnum = ps->dev->devnum,
-		.slow = ps->dev->speed == USB_SPEED_LOW
-	};
+	struct usbdevfs_connectinfo ci;
+
+	memset(&ci, 0, sizeof(ci));
+	ci.devnum = ps->dev->devnum;
+	ci.slow = ps->dev->speed == USB_SPEED_LOW;
 
 	if (copy_to_user(arg, &ci, sizeof(ci)))
 		return -EFAULT;