USB: serial: cyberjack: fix NULL-deref at open

Fix NULL-pointer dereference when clearing halt at open should the device
lack a bulk-out endpoint.

Unable to handle kernel NULL pointer dereference at virtual address 00000030
...
PC is at cyberjack_open+0x40/0x9c [cyberjack]

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/usb/serial/cyberjack.c b/drivers/usb/serial/cyberjack.c
index 5f17a3b9916d..80260b08398b 100644
--- a/drivers/usb/serial/cyberjack.c
+++ b/drivers/usb/serial/cyberjack.c
@@ -50,6 +50,7 @@
 #define CYBERJACK_PRODUCT_ID    0x0100
 
 /* Function prototypes */
+static int cyberjack_attach(struct usb_serial *serial);
 static int cyberjack_port_probe(struct usb_serial_port *port);
 static int cyberjack_port_remove(struct usb_serial_port *port);
 static int  cyberjack_open(struct tty_struct *tty,
@@ -77,6 +78,7 @@ static struct usb_serial_driver cyberjack_device = {
         .description =          "Reiner SCT Cyberjack USB card reader",
         .id_table =             id_table,
         .num_ports =            1,
+        .attach =               cyberjack_attach,
         .port_probe =           cyberjack_port_probe,
         .port_remove =          cyberjack_port_remove,
         .open =                 cyberjack_open,
@@ -100,6 +102,14 @@ struct cyberjack_private {
         short           wrsent;         /* Data already sent */
 };
 
+static int cyberjack_attach(struct usb_serial *serial)
+{
+        if (serial->num_bulk_out < serial->num_ports)
+                return -ENODEV;
+
+        return 0;
+}
+
 static int cyberjack_port_probe(struct usb_serial_port *port)
 {
         struct cyberjack_private *priv;