Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933096AbdC1Nof (ORCPT ); Tue, 28 Mar 2017 09:44:35 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:59082 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753317AbdC1MfC (ORCPT ); Tue, 28 Mar 2017 08:35:02 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold Subject: [PATCH 4.4 29/76] USB: uss720: fix NULL-deref at probe Date: Tue, 28 Mar 2017 14:30:26 +0200 Message-Id: <20170328122601.155840292@linuxfoundation.org> X-Mailer: git-send-email 2.12.1 In-Reply-To: <20170328122559.966310440@linuxfoundation.org> References: <20170328122559.966310440@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1210 Lines: 41 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold 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: Greg Kroah-Hartman --- drivers/usb/misc/uss720.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/usb/misc/uss720.c +++ b/drivers/usb/misc/uss720.c @@ -711,6 +711,11 @@ static int uss720_probe(struct usb_inter interface = intf->cur_altsetting; + if (interface->desc.bNumEndpoints < 3) { + usb_put_dev(usbdev); + return -ENODEV; + } + /* * Allocate parport interface */