UPSTREAM: USB: mct_u232: add sanity checking in probe
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
BUG: 28242610
Signed-off-by: Oliver Neukum <ONeukum@suse.com>
[johan: add error message ]
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Badhri Jagan Sridharan <Badhri@google.com>
Change-Id: I284ad648c2087c34a098d67e0cc6d948a568413c
(cherry picked from commit 0cd0c38fa2cef1cad28a2a9ecf9a60cff4cd4038)
diff --git a/drivers/usb/serial/mct_u232.c b/drivers/usb/serial/mct_u232.c
index fd707d6..89726f7 100644
--- a/drivers/usb/serial/mct_u232.c
+++ b/drivers/usb/serial/mct_u232.c
@@ -376,14 +376,21 @@
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);
