[PATCH 4.9 14/32] driver core: bus: Fix a potential double free

Greg Kroah-Hartman
2017-09-08T13:24:13Z

From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

commit 0f9b011d3321ca1079c7a46c18cb1956fbdb7bcb upstream.

The .release function of driver_ktype is 'driver_release()'.
This function frees the container_of this kobject.

So, this memory must not be freed explicitly in the error handling path of
'bus_add_driver()'. Otherwise a double free will occur.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/base/bus.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -736,7 +736,7 @@ int bus_add_driver(struct device_driver

out_unregister:
kobject_put(&priv->kobj);
- kfree(drv->p);
+ /* drv->p is freed in driver_release() */
drv->p = NULL;
out_put_bus:
bus_put(bus);