linux-kernel - [PATCH 3.16 075/133] driver core: bus: Fix a potential double free

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 22 Nov 2017 01:58:13 +0000
From:   Ben Hutchings <ben@...adent.org.uk>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:     akpm@...ux-foundation.org,
        "Christophe JAILLET" <christophe.jaillet@...adoo.fr>,
        "Greg Kroah-Hartman" <gregkh@...uxfoundation.org>
Subject: [PATCH 3.16 075/133] driver core: bus: Fix a potential double free

3.16.51-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Christophe JAILLET <christophe.jaillet@...adoo.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@...adoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 drivers/base/bus.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -722,7 +722,7 @@ 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);