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>

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index f0161d6..2c5a3e4 100644 (file)
--- 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;