[PATCH] usb: typec: fix use after free in typec_register_port()

From: Wen Yang
Date: Tue Nov 26 2019 - 09:05:06 EST


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@xxxxxxxxxxxxxxxxx>
Cc: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: linux-usb@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/usb/typec/class.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index 7ece6ca..91d6227 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -1612,14 +1612,16 @@ 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);
--
1.8.3.1