From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Tue, 29 Aug 2017 19:23:49 +0000 (+0200)
Subject: driver core: bus: Fix a potential double free
X-Git-Tag: v4.12.12~28
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=af617519a8c23bf0065398b6d3ad503035cf4aac;p=thirdparty%2Fkernel%2Fstable.git

driver core: bus: Fix a potential double free

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>
---

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 6470eb8088f4f..e32a74eb28a3e 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -736,7 +736,7 @@ int bus_add_driver(struct device_driver *drv)
 
 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);