serial: pch_uart: fix tty-kref leak in dma-rx path

Fix tty_kref leak when tty_buffer_request room fails in dma-rx path.

Note that the tty ref isn't really needed anymore, but as the leak has
always been there, fixing it before removing should makes it easier to
backport the fix.

Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index f0161d6ccc5c..2c5a3e4a17db 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -685,11 +685,12 @@ static int dma_push_rx(struct eg20t_port *priv, int size)
                 dev_warn(port->dev, "Rx overrun: dropping %u bytes\n",
                          size - room);
         if (!room)
-                return room;
+                goto out;
 
         tty_insert_flip_string(tport, sg_virt(&priv->sg_rx), size);
 
         port->icount.rx += room;
+out:
         tty_kref_put(tty);
 
         return room;