From: WANG Cong <xiyou.wangcong@xxxxxxxxx> [ Upstream commit 7afb8886a05be68e376655539a064ec672de8a8e ] Ignacy reported that when eth0 is down and add a vlan device on top of it like: ip link add link eth0 name eth0.1 up type vlan id 1 We will get a refcount leak: unregister_netdevice: waiting for eth0.1 to become free. Usage count = 2 The problem is when rtnl_configure_link() fails in rtnl_newlink(), we simply call unregister_device(), but for stacked device like vlan, we almost do nothing when we unregister the upper device, more work is done when we unregister the lower device, so call its ->dellink(). Reported-by: Ignacy Gawedzki <ignacy.gawedzki@xxxxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- net/core/rtnetlink.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index dd5e727..71706b5 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2099,8 +2099,16 @@ replay: } } err = rtnl_configure_link(dev, ifm); - if (err < 0) - unregister_netdevice(dev); + if (err < 0) { + if (ops->newlink) { + LIST_HEAD(list_kill); + + ops->dellink(dev, &list_kill); + unregister_netdevice_many(&list_kill); + } else { + unregister_netdevice(dev); + } + } out: put_net(dest_net); return err; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html