1 files changed, 11 insertions, 7 deletions

diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index cf8924f9a2cc..a6d1c75a1c89 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -499,7 +499,7 @@ static void visor_read_bulk_callback(struct urb *urb)
         int status = urb->status;
         struct tty_struct *tty;
         int result;
-        int available_room;
+        int available_room = 0;
 
         dbg("%s - port %d", __func__, port->number);
 
@@ -512,13 +512,17 @@ static void visor_read_bulk_callback(struct urb *urb)
         usb_serial_debug_data(debug, &port->dev, __func__,
                                                 urb->actual_length, data);
 
-        tty = port->port.tty;
-        if (tty && urb->actual_length) {
-                available_room = tty_buffer_request_room(tty,
+        if (urb->actual_length) {
+                tty = tty_port_tty_get(&port->port);
+                if (tty) {
+                        available_room = tty_buffer_request_room(tty,
                                                         urb->actual_length);
-                if (available_room) {
-                        tty_insert_flip_string(tty, data, available_room);
-                        tty_flip_buffer_push(tty);
+                        if (available_room) {
+                                tty_insert_flip_string(tty, data,
+                                                        available_room);
+                                tty_flip_buffer_push(tty);
+                        }
+                        tty_kref_put(tty);
                 }
                 spin_lock(&priv->lock);
                 priv->bytes_in += available_room;