usb: typec: fix use after free in typec_register_port()

commit 5c388abefda0d92355714010c0199055c57ab6c7 upstream.

We can't use "port->sw" and/or "port->mux" after it has been freed.

Fixes: 23481121c81d ("usb: typec: class: Don't use port parent for getting mux handles")
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Cc: stable <stable@vger.kernel.org>
Cc: linux-usb@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191126140452.14048-1-wenyang@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index a18285a990a88e52770e14841c36ba618ea0ed61..78fc5fa963c3288285c410cad7075372ff5bf10c 100644 (file)
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -1604,14 +1604,16 @@ struct typec_port *typec_register_port(struct device *parent,
 
        port->sw = typec_switch_get(&port->dev);
        if (IS_ERR(port->sw)) {
+               ret = PTR_ERR(port->sw);
                put_device(&port->dev);
-               return ERR_CAST(port->sw);
+               return ERR_PTR(ret);
        }
 
        port->mux = typec_mux_get(&port->dev, NULL);
        if (IS_ERR(port->mux)) {
+               ret = PTR_ERR(port->mux);
                put_device(&port->dev);
-               return ERR_CAST(port->mux);
+               return ERR_PTR(ret);
        }
 
        ret = device_add(&port->dev);