From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Benc Subject: Re: [PATCH net-next 3/3] vxlan: allow multiple VXLANs with same VNI for IPv6 link-local addresses Date: Tue, 14 Mar 2017 16:28:15 +0100 Message-ID: <20170314162815.7aae9e94@griffin> References: <5c74248483272110d0ca249b80b943b0ceb0b610.1489184335.git.mschiffer@universe-factory.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: davem@davemloft.net, hannes@stressinduktion.org, pshelar@ovn.org, aduyck@mirantis.com, roopa@cumulusnetworks.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: Matthias Schiffer Return-path: In-Reply-To: <5c74248483272110d0ca249b80b943b0ceb0b610.1489184335.git.mschiffer@universe-factory.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, 10 Mar 2017 23:39:44 +0100, Matthias Schiffer wrote: > @@ -233,17 +234,30 @@ static struct vxlan_dev *vxlan_vs_find_vni(struct vxlan_sock *vs, __be32 vni) > vni = 0; > > hlist_for_each_entry_rcu(vxlan, vni_head(vs, vni), hlist) { > - if (vxlan->default_dst.remote_vni == vni) > - return vxlan; > + if (vxlan->default_dst.remote_vni != vni) > + continue; > + > + if (IS_ENABLED(CONFIG_IPV6)) { > + const struct vxlan_config *cfg = &vxlan->cfg; > + > + if (cfg->remote_ifindex != 0 && > + cfg->remote_ifindex != ifindex && > + cfg->saddr.sa.sa_family == AF_INET6 && > + (ipv6_addr_type(&cfg->saddr.sin6.sin6_addr) & > + IPV6_ADDR_LINKLOCAL)) Calculating this (especially ipv6_addr_type) on every received packet looks unnecessarily expensive. Just store the fact the the local address is link-local in a flag during config. And compare the flag first before considering remote_ifindex. This is especially important for lwtunnels which can have anything in the saddr and remote_ifindex, yet those fields are ignored and the vni 0 entry has to be returned. It also means that the link-local flag must not be set for lwtunnels. > +#if IS_ENABLED(CONFIG_IPV6) > + if (conf->remote_ifindex != tmp->cfg.remote_ifindex && > + conf->saddr.sa.sa_family == AF_INET6 && > + tmp->cfg.saddr.sa.sa_family == AF_INET6 && > + (ipv6_addr_type(&conf->saddr.sin6.sin6_addr) & > + IPV6_ADDR_LINKLOCAL) && > + (ipv6_addr_type(&tmp->cfg.saddr.sin6.sin6_addr) & > + IPV6_ADDR_LINKLOCAL)) > + continue; > +#endif In patch 1, you're checking for either source and destination address being link-local, while here you're consider only those that have both addresses link-local. Wouldn't it be better to plainly reject configuration that has one address link-local but not the other one? Jiri