Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965099AbdCJN77 (ORCPT ); Fri, 10 Mar 2017 08:59:59 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42442 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933223AbdCJLvo (ORCPT ); Fri, 10 Mar 2017 06:51:44 -0500 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" Date: Fri, 10 Mar 2017 11:46:22 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 170/370] USB: serial: oti6858: fix NULL-deref at open 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: 2052 Lines: 65 3.16.42-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 5afeef2366db14587b65558bbfd5a067542e07fb upstream. Fix NULL-pointer dereference in open() should the device lack the expected endpoints: Unable to handle kernel NULL pointer dereference at virtual address 00000030 ... PC is at oti6858_open+0x30/0x1d0 [oti6858] Note that a missing interrupt-in endpoint would have caused open() to fail. Fixes: 49cdee0ed0fc ("USB: oti6858 usb-serial driver (in Nokia CA-42 cable)") Signed-off-by: Johan Hovold Signed-off-by: Ben Hutchings --- drivers/usb/serial/oti6858.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) --- a/drivers/usb/serial/oti6858.c +++ b/drivers/usb/serial/oti6858.c @@ -134,6 +134,7 @@ static int oti6858_chars_in_buffer(struc static int oti6858_tiocmget(struct tty_struct *tty); static int oti6858_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear); +static int oti6858_attach(struct usb_serial *serial); static int oti6858_port_probe(struct usb_serial_port *port); static int oti6858_port_remove(struct usb_serial_port *port); @@ -158,6 +159,7 @@ static struct usb_serial_driver oti6858_ .write_bulk_callback = oti6858_write_bulk_callback, .write_room = oti6858_write_room, .chars_in_buffer = oti6858_chars_in_buffer, + .attach = oti6858_attach, .port_probe = oti6858_port_probe, .port_remove = oti6858_port_remove, }; @@ -324,6 +326,20 @@ static void send_data(struct work_struct usb_serial_port_softint(port); } +static int oti6858_attach(struct usb_serial *serial) +{ + unsigned char num_ports = serial->num_ports; + + if (serial->num_bulk_in < num_ports || + serial->num_bulk_out < num_ports || + serial->num_interrupt_in < num_ports) { + dev_err(&serial->interface->dev, "missing endpoints\n"); + return -ENODEV; + } + + return 0; +} + static int oti6858_port_probe(struct usb_serial_port *port) { struct oti6858_private *priv;