Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756030AbdGLA6P (ORCPT ); Tue, 11 Jul 2017 20:58:15 -0400 Received: from galahad.ideasonboard.com ([185.26.127.97]:60241 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753681AbdGLA6N (ORCPT ); Tue, 11 Jul 2017 20:58:13 -0400 From: Laurent Pinchart To: Guenter Roeck Cc: Richard Simmons , Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Robb Glasser Subject: Re: [PATCH v2] [media] uvcvideo: Prevent heap overflow in uvc driver Date: Wed, 12 Jul 2017 03:58:15 +0300 Message-ID: <2146699.kzif97nFig@avalon> User-Agent: KMail/4.14.10 (Linux/4.9.34-gentoo; KDE/4.14.32; x86_64; ; ) In-Reply-To: <1498839716-31918-1-git-send-email-linux@roeck-us.net> References: <1498839716-31918-1-git-send-email-linux@roeck-us.net> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1695 Lines: 55 Hi Guenter, Thank you for the patch and sorry for the late reply. On Friday 30 Jun 2017 09:21:56 Guenter Roeck wrote: > The size of uvc_control_mapping is user controlled leading to a > potential heap overflow in the uvc driver. This adds a check to verify > the user provided size fits within the bounds of the defined buffer > size. > > Originally-from: Richard Simmons > Signed-off-by: Guenter Roeck This looks good to me. Reviewed-by: Laurent Pinchart and taken in my tree for v4.14 with a Cc: stable@vger.kernel.org tag to get it backported to stable kernels. > --- > Fixes CVE-2017-0627. > > v2: Combination of v1 with the fix suggested by Richard Simmons > Perform validation after uvc_ctrl_fill_xu_info() > Take into account that ctrl->info.size is in bytes > Also validate mapping->size > > drivers/media/usb/uvc/uvc_ctrl.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/media/usb/uvc/uvc_ctrl.c > b/drivers/media/usb/uvc/uvc_ctrl.c index c2ee6e39fd0c..d3e3164f43fd 100644 > --- a/drivers/media/usb/uvc/uvc_ctrl.c > +++ b/drivers/media/usb/uvc/uvc_ctrl.c > @@ -2002,6 +2002,13 @@ int uvc_ctrl_add_mapping(struct uvc_video_chain > *chain, goto done; > } > > + /* validate that the user provided bit-size and offset is valid */ > + if (mapping->size > 32 || > + mapping->offset + mapping->size > ctrl->info.size * 8) { > + ret = -EINVAL; > + goto done; > + } > + > list_for_each_entry(map, &ctrl->info.mappings, list) { > if (mapping->id == map->id) { > uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', " -- Regards, Laurent Pinchart