Subject:    [PATCH v2] mct_u232: sanity checking in probe

From:       Oliver Neukum <oneukum@suse.com>

Date:       2016-03-21 13:14:37

An attack using the lack of sanity checking in probe

is known. This patch checks for the existance of a

second port.

CVE-2016-3136

Signed-off-by: Oliver Neukum <ONeukum@suse.com>

CC: stable@vger.kernel.org

v1 - add sanity check for presence of a second port

v2 - add sanity check for an interrupt endpoint

---

 drivers/usb/serial/mct_u232.c | 4 ++++

 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/serial/mct_u232.c b/drivers/usb/serial/mct_u232.c

index 4446b8d..3e64538 100644

--- a/drivers/usb/serial/mct_u232.c

+++ b/drivers/usb/serial/mct_u232.c

@@ -378,6 +378,10 @@ static int mct_u232_port_probe(struct usb_serial_port *port)

 {

 	struct mct_u232_private *priv;

+	/* check first to simplify error handling */

+	if (!port->serial->port[1] || !port->serial->port[1]->interrupt_in_urb)

+		return -ENODEV;

+

 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);

 	if (!priv)

 		return -ENOMEM;

-- 

2.1.4