Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751740AbdFAPtl (ORCPT ); Thu, 1 Jun 2017 11:49:41 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33813 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752380AbdFAPpW (ORCPT ); Thu, 1 Jun 2017 11:45:22 -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" , "Greg Kroah-Hartman" Date: Thu, 01 Jun 2017 16:43:16 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 181/212] USB: iowarrior: fix NULL-deref at probe In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 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 Content-Length: 1973 Lines: 54 3.16.44-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit b7321e81fc369abe353cf094d4f0dc2fe11ab95f upstream. Make sure to check for the required interrupt-in endpoint to avoid dereferencing a NULL-pointer should a malicious device lack such an endpoint. Note that a fairly recent change purported to fix this issue, but added an insufficient test on the number of endpoints only, a test which can now be removed. Fixes: 4ec0ef3a8212 ("USB: iowarrior: fix oops with malicious USB descriptors") Fixes: 946b960d13c1 ("USB: add driver for iowarrior devices.") Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/misc/iowarrior.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) --- a/drivers/usb/misc/iowarrior.c +++ b/drivers/usb/misc/iowarrior.c @@ -787,12 +787,6 @@ static int iowarrior_probe(struct usb_in iface_desc = interface->cur_altsetting; dev->product_id = le16_to_cpu(udev->descriptor.idProduct); - if (iface_desc->desc.bNumEndpoints < 1) { - dev_err(&interface->dev, "Invalid number of endpoints\n"); - retval = -EINVAL; - goto error; - } - /* set up the endpoint information */ for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { endpoint = &iface_desc->endpoint[i].desc; @@ -803,6 +797,13 @@ static int iowarrior_probe(struct usb_in /* this one will match for the IOWarrior56 only */ dev->int_out_endpoint = endpoint; } + + if (!dev->int_in_endpoint) { + dev_err(&interface->dev, "no interrupt-in endpoint found\n"); + retval = -ENODEV; + goto error; + } + /* we have to check the report_size often, so remember it in the endianness suitable for our machine */ dev->report_size = usb_endpoint_maxp(dev->int_in_endpoint); if ((dev->interface->cur_altsetting->desc.bInterfaceNumber == 0) &&