From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:60804 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1163411AbdAJNqC (ORCPT ); Tue, 10 Jan 2017 08:46:02 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold Subject: [PATCH 4.9 057/206] USB: serial: kobil_sct: fix NULL-deref in write Date: Tue, 10 Jan 2017 14:35:40 +0100 Message-Id: <20170110131505.153824298@linuxfoundation.org> In-Reply-To: <20170110131502.767555407@linuxfoundation.org> References: <20170110131502.767555407@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable 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: Greg Kroah-Hartman --- 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;