Commit dcbc0ae4 authored by Johan Hovold's avatar Johan Hovold
Browse files

USB: serial: digi_acceleport: add chars_in_buffer locking 



Both the dp_write_urb_in_use flag and dp_out_buf_len counter should be
accessed while holding the driver port lock. Add the missing locking to
chars_in_buffer and clean up the implementation somewhat by using a
common exit path.

Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
parent 3aed3af2

drivers/usb/serial/digi_acceleport.c

+11 −9
Original line number Diff line number Diff line
@@ -1044,17 +1044,19 @@ static unsigned int digi_chars_in_buffer(struct tty_struct *tty) 
{

	struct usb_serial_port *port = tty->driver_data;

	struct digi_port *priv = usb_get_serial_port_data(port);

	unsigned long flags;

	unsigned int chars;



	if (priv->dp_write_urb_in_use) {

		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",

			priv->dp_port_num, port->bulk_out_size - 2);

		return port->bulk_out_size - 2;

	} else {

		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",

			priv->dp_port_num, priv->dp_out_buf_len);

		return priv->dp_out_buf_len;

	}

	spin_lock_irqsave(&priv->dp_port_lock, flags);

	if (priv->dp_write_urb_in_use)

		chars = port->bulk_out_size - 2;

	else

		chars = priv->dp_out_buf_len;

	spin_unlock_irqrestore(&priv->dp_port_lock, flags);



	dev_dbg(&port->dev, "%s: port=%d, chars=%d\n", __func__,

			priv->dp_port_num, chars);

	return chars;

}



static void digi_dtr_rts(struct usb_serial_port *port, int on)