From: Elina Pasheva <epasheva@xxxxxxxxxxxxxxxxxx> A crash has been reported with sierra driver on disconnect with Ubuntu/Lucid distribution based on kernel-2.6.32. The cause of the crash was determined as "NULL tty pointer was being referenced" and the NULL pointer was passed by sierra_indat_callback(). This patch modifies sierra_indat_callback() function to check for NULL tty structure pointer. This modification prevents a crash from happening when the device is disconnected. This patch fixes the bug reported in Launchpad: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/511157 Signed-off-by: Elina Pasheva <epasheva@xxxxxxxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx> --- drivers/usb/serial/sierra.c | 19 +++++++++++-------- 1 files changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/usb/serial/sierra.c b/drivers/usb/serial/sierra.c index 6aeea40..fcec466 100644 --- a/drivers/usb/serial/sierra.c +++ b/drivers/usb/serial/sierra.c @@ -594,14 +594,17 @@ static void sierra_indat_callback(struct urb *urb) } else { if (urb->actual_length) { tty = tty_port_tty_get(&port->port); - - tty_buffer_request_room(tty, urb->actual_length); - tty_insert_flip_string(tty, data, urb->actual_length); - tty_flip_buffer_push(tty); - - tty_kref_put(tty); - usb_serial_debug_data(debug, &port->dev, __func__, - urb->actual_length, data); + if (tty) { + tty_buffer_request_room(tty, + urb->actual_length); + tty_insert_flip_string(tty, data, + urb->actual_length); + tty_flip_buffer_push(tty); + + tty_kref_put(tty); + usb_serial_debug_data(debug, &port->dev, + __func__, urb->actual_length, data); + } } else { dev_dbg(&port->dev, "%s: empty read urb" " received\n", __func__); -- 1.7.0.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
