USB: serial: fix null-pointer dereferences on disconnect

[karo-tx-linux.git] / drivers / usb / serial / ftdi_sio.c

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 90ceef1776c34197c65fb58988e0fc5771184a35..d07fccf3bab5caa431dd5d77d3d552913a89ac9c 100644 (file)
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1886,24 +1886,22 @@ static void ftdi_dtr_rts(struct usb_serial_port *port, int on)
 {
        struct ftdi_private *priv = usb_get_serial_port_data(port);
 
-       mutex_lock(&port->serial->disc_mutex);
-       if (!port->serial->disconnected) {
-               /* Disable flow control */
-               if (!on && usb_control_msg(port->serial->dev,
+       /* Disable flow control */
+       if (!on) {
+               if (usb_control_msg(port->serial->dev,
                            usb_sndctrlpipe(port->serial->dev, 0),
                            FTDI_SIO_SET_FLOW_CTRL_REQUEST,
                            FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
                            0, priv->interface, NULL, 0,
                            WDR_TIMEOUT) < 0) {
-                           dev_err(&port->dev, "error from flowcontrol urb\n");
+                       dev_err(&port->dev, "error from flowcontrol urb\n");
                }
-               /* drop RTS and DTR */
-               if (on)
-                       set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
-               else
-                       clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
        }
-       mutex_unlock(&port->serial->disc_mutex);
+       /* drop RTS and DTR */
+       if (on)
+               set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
+       else
+               clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
 }
 
 /*