Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754573AbdDJPuh (ORCPT ); Mon, 10 Apr 2017 11:50:37 -0400 Received: from mx2.suse.de ([195.135.220.15]:38171 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754463AbdDJPee (ORCPT ); Mon, 10 Apr 2017 11:34:34 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Johan Hovold , Jiri Slaby Subject: [PATCH 3.12 085/142] USB: uss720: fix NULL-deref at probe Date: Mon, 10 Apr 2017 17:32:46 +0200 Message-Id: <54e9ccc3d461030fd987d8e3734287ed3c897425.1491838390.git.jslaby@suse.cz> X-Mailer: git-send-email 2.12.2 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1312 Lines: 43 From: Johan Hovold 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit f259ca3eed6e4b79ac3d5c5c9fb259fb46e86217 upstream. Make sure to check the number of endpoints to avoid dereferencing a NULL-pointer or accessing memory beyond the endpoint array should a malicious device lack the expected endpoints. Note that the endpoint access that causes the NULL-deref is currently only used for debugging purposes during probe so the oops only happens when dynamic debugging is enabled. This means the driver could be rewritten to continue to accept device with only two endpoints, should such devices exist. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold Signed-off-by: Jiri Slaby --- drivers/usb/misc/uss720.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/usb/misc/uss720.c b/drivers/usb/misc/uss720.c index 40ef40affe83..3cb05eb5f1df 100644 --- a/drivers/usb/misc/uss720.c +++ b/drivers/usb/misc/uss720.c @@ -715,6 +715,11 @@ static int uss720_probe(struct usb_interface *intf, interface = intf->cur_altsetting; + if (interface->desc.bNumEndpoints < 3) { + usb_put_dev(usbdev); + return -ENODEV; + } + /* * Allocate parport interface */ -- 2.12.2