Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937567AbdCJN5e (ORCPT ); Fri, 10 Mar 2017 08:57:34 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42912 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933122AbdCJLv6 (ORCPT ); Fri, 10 Mar 2017 06:51:58 -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 3.16 162/370] USB: serial: kobil_sct: fix NULL-deref in write 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: 1691 Lines: 57 3.16.42-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 21ce57840243c7b70fbc1ebd3dceeb70bb6e9e09 upstream. Fix NULL-pointer dereference in write() should the device lack the expected interrupt-out endpoint: Unable to handle kernel NULL pointer dereference at virtual address 00000054 ... PC is at kobil_write+0x144/0x2a0 [kobil_sct] Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold Signed-off-by: Ben Hutchings --- drivers/usb/serial/kobil_sct.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/drivers/usb/serial/kobil_sct.c +++ b/drivers/usb/serial/kobil_sct.c @@ -51,6 +51,7 @@ /* Function prototypes */ +static int kobil_attach(struct usb_serial *serial); static int kobil_port_probe(struct usb_serial_port *probe); static int kobil_port_remove(struct usb_serial_port *probe); static int kobil_open(struct tty_struct *tty, struct usb_serial_port *port); @@ -86,6 +87,7 @@ static struct usb_serial_driver kobil_de .description = "KOBIL USB smart card terminal", .id_table = id_table, .num_ports = 1, + .attach = kobil_attach, .port_probe = kobil_port_probe, .port_remove = kobil_port_remove, .ioctl = kobil_ioctl, @@ -113,6 +115,16 @@ struct kobil_private { }; +static int kobil_attach(struct usb_serial *serial) +{ + if (serial->num_interrupt_out < serial->num_ports) { + dev_err(&serial->interface->dev, "missing interrupt-out endpoint\n"); + return -ENODEV; + } + + return 0; +} + static int kobil_port_probe(struct usb_serial_port *port) { struct usb_serial *serial = port->serial;