| Message ID | 1452162413-4227-1-git-send-email-nicolas.dichtel@6wind.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Nicolas Dichtel <nicolas.dichtel@6wind.com> Date: Thu, 7 Jan 2016 11:26:53 +0100 > When a vxlan interface is created, the driver checks that there is not > another vxlan interface with the same properties. To do this, it checks > the existing vxlan udp socket. Since commit 1c51a9159dde, the creation of > the vxlan socket is done only when the interface is set up, thus it breaks > that test. > > Example: > $ ip l a vxlan10 type vxlan id 10 group 239.0.0.10 dev eth0 dstport 0 > $ ip l a vxlan11 type vxlan id 10 group 239.0.0.10 dev eth0 dstport 0 > $ ip -br l | grep vxlan > vxlan10 DOWN f2:55:1c:6a:fb:00 <BROADCAST,MULTICAST> > vxlan11 DOWN 7a:cb:b9:38:59:0d <BROADCAST,MULTICAST> > > Instead of checking sockets, let's loop over the vxlan iface list. > > Fixes: 1c51a9159dde ("vxlan: fix race caused by dropping rtnl_unlock") > Reported-by: Thomas Faivre <thomas.faivre@6wind.com> > Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Applied and queued up for -stable, thanks.
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index ba363cedef80..405a7b6cca25 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -2751,7 +2751,7 @@ static int vxlan_dev_configure(struct net *src_net, struct net_device *dev, struct vxlan_config *conf) { struct vxlan_net *vn = net_generic(src_net, vxlan_net_id); - struct vxlan_dev *vxlan = netdev_priv(dev); + struct vxlan_dev *vxlan = netdev_priv(dev), *tmp; struct vxlan_rdst *dst = &vxlan->default_dst; unsigned short needed_headroom = ETH_HLEN; int err; @@ -2817,9 +2817,15 @@ static int vxlan_dev_configure(struct net *src_net, struct net_device *dev, if (!vxlan->cfg.age_interval) vxlan->cfg.age_interval = FDB_AGE_DEFAULT; - if (vxlan_find_vni(src_net, conf->vni, use_ipv6 ? AF_INET6 : AF_INET, - vxlan->cfg.dst_port, vxlan->flags)) + list_for_each_entry(tmp, &vn->vxlan_list, next) { + if (tmp->cfg.vni == conf->vni && + (tmp->default_dst.remote_ip.sa.sa_family == AF_INET6 || + tmp->cfg.saddr.sa.sa_family == AF_INET6) == use_ipv6 && + tmp->cfg.dst_port == vxlan->cfg.dst_port && + (tmp->flags & VXLAN_F_RCV_FLAGS) == + (vxlan->flags & VXLAN_F_RCV_FLAGS)) return -EEXIST; + } dev->ethtool_ops = &vxlan_ethtool_ops;
When a vxlan interface is created, the driver checks that there is not another vxlan interface with the same properties. To do this, it checks the existing vxlan udp socket. Since commit 1c51a9159dde, the creation of the vxlan socket is done only when the interface is set up, thus it breaks that test. Example: $ ip l a vxlan10 type vxlan id 10 group 239.0.0.10 dev eth0 dstport 0 $ ip l a vxlan11 type vxlan id 10 group 239.0.0.10 dev eth0 dstport 0 $ ip -br l | grep vxlan vxlan10 DOWN f2:55:1c:6a:fb:00 <BROADCAST,MULTICAST> vxlan11 DOWN 7a:cb:b9:38:59:0d <BROADCAST,MULTICAST> Instead of checking sockets, let's loop over the vxlan iface list. Fixes: 1c51a9159dde ("vxlan: fix race caused by dropping rtnl_unlock") Reported-by: Thomas Faivre <thomas.faivre@6wind.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> --- drivers/net/vxlan.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)