Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759896AbcDJTDQ (ORCPT ); Sun, 10 Apr 2016 15:03:16 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:53193 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756718AbcDJS6z (ORCPT ); Sun, 10 Apr 2016 14:58:55 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oliver Neukum , Johan Hovold Subject: [PATCH 4.4 058/210] USB: mct_u232: add sanity checking in probe Date: Sun, 10 Apr 2016 11:34:39 -0700 Message-Id: <20160410183528.711301668@linuxfoundation.org> X-Mailer: git-send-email 2.8.0 In-Reply-To: <20160410183526.651820045@linuxfoundation.org> References: <20160410183526.651820045@linuxfoundation.org> User-Agent: quilt/0.64 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: 1404 Lines: 48 4.4-stable 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 --- 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);