Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754880AbcD0AEX (ORCPT ); Tue, 26 Apr 2016 20:04:23 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:40143 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754055AbcDZXOE (ORCPT ); Tue, 26 Apr 2016 19:14:04 -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, "Greg Kroah-Hartman" , "Johan Hovold" , "Oliver Neukum" , "Oliver Neukum" Date: Wed, 27 Apr 2016 01:02:21 +0200 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 155/217] USB: mct_u232: add sanity checking in probe In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8426:ae4:c500:9cba:69ae:962d:6167 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: 1451 Lines: 47 3.16.35-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Neukum commit 4e9a0b05257f29cf4b75f3209243ed71614d062e upstream. An attack using the lack of sanity checking in probe is known. This patch checks for the existence of a second port. CVE-2016-3136 Signed-off-by: Oliver Neukum [johan: add error message ] Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/serial/mct_u232.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/drivers/usb/serial/mct_u232.c +++ b/drivers/usb/serial/mct_u232.c @@ -376,14 +376,21 @@ static void mct_u232_msr_to_state(struct static int mct_u232_port_probe(struct usb_serial_port *port) { + struct usb_serial *serial = port->serial; struct mct_u232_private *priv; + /* check first to simplify error handling */ + if (!serial->port[1] || !serial->port[1]->interrupt_in_urb) { + dev_err(&port->dev, "expected endpoint missing\n"); + return -ENODEV; + } + priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; /* Use second interrupt-in endpoint for reading. */ - priv->read_urb = port->serial->port[1]->interrupt_in_urb; + priv->read_urb = serial->port[1]->interrupt_in_urb; priv->read_urb->context = port; spin_lock_init(&priv->lock);