From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754227AbaHDRSi (ORCPT ); Mon, 4 Aug 2014 13:18:38 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:56448 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751692AbaHDQty (ORCPT ); Mon, 4 Aug 2014 12:49:54 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Johan Hovold" , "Mike Remski" Date: Mon, 04 Aug 2014 17:48:31 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 07/94] USB: ftdi_sio: fix null deref at port probe In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.62-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit aea1ae8760314e072bf1b773521e9de5d5dda10d upstream. Fix NULL-pointer dereference when probing an interface with no endpoints. These devices have two bulk endpoints per interface, but this avoids crashing the kernel if a user forces a non-FTDI device to be probed. Note that the iterator variable was made unsigned in order to avoid a maybe-uninitialized compiler warning for ep_desc after the loop. Fixes: 895f28badce9 ("USB: ftdi_sio: fix hi-speed device packet size calculation") Reported-by: Mike Remski Tested-by: Mike Remski Signed-off-by: Johan Hovold Signed-off-by: Ben Hutchings --- drivers/usb/serial/ftdi_sio.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/usb/serial/ftdi_sio.c +++ b/drivers/usb/serial/ftdi_sio.c @@ -1591,14 +1591,17 @@ static void ftdi_set_max_packet_size(str struct usb_device *udev = serial->dev; struct usb_interface *interface = serial->interface; - struct usb_endpoint_descriptor *ep_desc = &interface->cur_altsetting->endpoint[1].desc; + struct usb_endpoint_descriptor *ep_desc; unsigned num_endpoints; - int i; + unsigned i; num_endpoints = interface->cur_altsetting->desc.bNumEndpoints; dev_info(&udev->dev, "Number of endpoints %d\n", num_endpoints); + if (!num_endpoints) + return; + /* NOTE: some customers have programmed FT232R/FT245R devices * with an endpoint size of 0 - not good. In this case, we * want to override the endpoint descriptor setting and use a