This is a note to let you know that I've just added the patch titled
macvlan: Fix one possible double free
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
macvlan-fix-one-possible-double-free.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Wed Feb 28 16:13:29 CET 2018
From: Gao Feng <gfree.wind@xxxxxxxxxxx>
Date: Tue, 26 Dec 2017 21:44:32 +0800
Subject: macvlan: Fix one possible double free
From: Gao Feng <gfree.wind@xxxxxxxxxxx>
[ Upstream commit d02fd6e7d2933ede6478a15f9e4ce8a93845824e ]
Because the macvlan_uninit would free the macvlan port, so there is one
double free case in macvlan_common_newlink. When the macvlan port is just
created, then register_netdevice or netdev_upper_dev_link failed and they
would invoke macvlan_uninit. Then it would reach the macvlan_port_destroy
which triggers the double free.
Signed-off-by: Gao Feng <gfree.wind@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/macvlan.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -1377,9 +1377,14 @@ int macvlan_common_newlink(struct net *s
return 0;
unregister_netdev:
+ /* macvlan_uninit would free the macvlan port */
unregister_netdevice(dev);
+ return err;
destroy_macvlan_port:
- if (create)
+ /* the macvlan port may be freed by macvlan_uninit when fail to register.
+ * so we destroy the macvlan port only when it's valid.
+ */
+ if (create && macvlan_port_get_rtnl(dev))
macvlan_port_destroy(port->dev);
return err;
}
Patches currently in stable-queue which might be from gfree.wind@xxxxxxxxxxx are
queue-4.9/macvlan-fix-one-possible-double-free.patch