vxlan: fix nonfunctional neigh_reduce()

[~andy/linux] / drivers / net / vxlan.c

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index a7eb3f28db6c614cff6c1dff9043f62971c91e86..1236812c7be69975487e7956c24d39718997ec2b 100644 (file)
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1342,15 +1342,103 @@ out:
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
+
+static struct sk_buff *vxlan_na_create(struct sk_buff *request,
+       struct neighbour *n, bool isrouter)
+{
+       struct net_device *dev = request->dev;
+       struct sk_buff *reply;
+       struct nd_msg *ns, *na;
+       struct ipv6hdr *pip6;
+       u8 *daddr;
+       int na_olen = 8; /* opt hdr + ETH_ALEN for target */
+       int ns_olen;
+       int i, len;
+
+       if (dev == NULL)
+               return NULL;
+
+       len = LL_RESERVED_SPACE(dev) + sizeof(struct ipv6hdr) +
+               sizeof(*na) + na_olen + dev->needed_tailroom;
+       reply = alloc_skb(len, GFP_ATOMIC);
+       if (reply == NULL)
+               return NULL;
+
+       reply->protocol = htons(ETH_P_IPV6);
+       reply->dev = dev;
+       skb_reserve(reply, LL_RESERVED_SPACE(request->dev));
+       skb_push(reply, sizeof(struct ethhdr));
+       skb_set_mac_header(reply, 0);
+
+       ns = (struct nd_msg *)skb_transport_header(request);
+
+       daddr = eth_hdr(request)->h_source;
+       ns_olen = request->len - skb_transport_offset(request) - sizeof(*ns);
+       for (i = 0; i < ns_olen-1; i += (ns->opt[i+1]<<3)) {
+               if (ns->opt[i] == ND_OPT_SOURCE_LL_ADDR) {
+                       daddr = ns->opt + i + sizeof(struct nd_opt_hdr);
+                       break;
+               }
+       }
+
+       /* Ethernet header */
+       ether_addr_copy(eth_hdr(reply)->h_dest, daddr);
+       ether_addr_copy(eth_hdr(reply)->h_source, n->ha);
+       eth_hdr(reply)->h_proto = htons(ETH_P_IPV6);
+       reply->protocol = htons(ETH_P_IPV6);
+
+       skb_pull(reply, sizeof(struct ethhdr));
+       skb_set_network_header(reply, 0);
+       skb_put(reply, sizeof(struct ipv6hdr));
+
+       /* IPv6 header */
+
+       pip6 = ipv6_hdr(reply);
+       memset(pip6, 0, sizeof(struct ipv6hdr));
+       pip6->version = 6;
+       pip6->priority = ipv6_hdr(request)->priority;
+       pip6->nexthdr = IPPROTO_ICMPV6;
+       pip6->hop_limit = 255;
+       pip6->daddr = ipv6_hdr(request)->saddr;
+       pip6->saddr = *(struct in6_addr *)n->primary_key;
+
+       skb_pull(reply, sizeof(struct ipv6hdr));
+       skb_set_transport_header(reply, 0);
+
+       na = (struct nd_msg *)skb_put(reply, sizeof(*na) + na_olen);
+
+       /* Neighbor Advertisement */
+       memset(na, 0, sizeof(*na)+na_olen);
+       na->icmph.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
+       na->icmph.icmp6_router = isrouter;
+       na->icmph.icmp6_override = 1;
+       na->icmph.icmp6_solicited = 1;
+       na->target = ns->target;
+       ether_addr_copy(&na->opt[2], n->ha);
+       na->opt[0] = ND_OPT_TARGET_LL_ADDR;
+       na->opt[1] = na_olen >> 3;
+
+       na->icmph.icmp6_cksum = csum_ipv6_magic(&pip6->saddr,
+               &pip6->daddr, sizeof(*na)+na_olen, IPPROTO_ICMPV6,
+               csum_partial(na, sizeof(*na)+na_olen, 0));
+
+       pip6->payload_len = htons(sizeof(*na)+na_olen);
+
+       skb_push(reply, sizeof(struct ipv6hdr));
+
+       reply->ip_summed = CHECKSUM_UNNECESSARY;
+
+       return reply;
+}
+
 static int neigh_reduce(struct net_device *dev, struct sk_buff *skb)
 {
        struct vxlan_dev *vxlan = netdev_priv(dev);
-       struct neighbour *n;
-       union vxlan_addr ipa;
+       struct nd_msg *msg;
        const struct ipv6hdr *iphdr;
        const struct in6_addr *saddr, *daddr;
-       struct nd_msg *msg;
-       struct inet6_dev *in6_dev = NULL;
+       struct neighbour *n;
+       struct inet6_dev *in6_dev;
 
        in6_dev = __in6_dev_get(dev);
        if (!in6_dev)
@@ -1363,19 +1451,20 @@ static int neigh_reduce(struct net_device *dev, struct sk_buff *skb)
        saddr = &iphdr->saddr;
        daddr = &iphdr->daddr;
 
-       if (ipv6_addr_loopback(daddr) ||
-           ipv6_addr_is_multicast(daddr))
-               goto out;
-
        msg = (struct nd_msg *)skb_transport_header(skb);
        if (msg->icmph.icmp6_code != 0 ||
            msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION)
                goto out;
 
-       n = neigh_lookup(ipv6_stub->nd_tbl, daddr, dev);
+       if (ipv6_addr_loopback(daddr) ||
+           ipv6_addr_is_multicast(&msg->target))
+               goto out;
+
+       n = neigh_lookup(ipv6_stub->nd_tbl, &msg->target, dev);
 
        if (n) {
                struct vxlan_fdb *f;
+               struct sk_buff *reply;
 
                if (!(n->nud_state & NUD_CONNECTED)) {
                        neigh_release(n);
@@ -1389,13 +1478,23 @@ static int neigh_reduce(struct net_device *dev, struct sk_buff *skb)
                        goto out;
                }
 
-               ipv6_stub->ndisc_send_na(dev, n, saddr, &msg->target,
-                                        !!in6_dev->cnf.forwarding,
-                                        true, false, false);
+               reply = vxlan_na_create(skb, n,
+                                       !!(f ? f->flags & NTF_ROUTER : 0));
+
                neigh_release(n);
+
+               if (reply == NULL)
+                       goto out;
+
+               if (netif_rx_ni(reply) == NET_RX_DROP)
+                       dev->stats.rx_dropped++;
+
        } else if (vxlan->flags & VXLAN_F_L3MISS) {
-               ipa.sin6.sin6_addr = *daddr;
-               ipa.sa.sa_family = AF_INET6;
+               union vxlan_addr ipa = {
+                       .sin6.sin6_addr = msg->target,
+                       .sa.sa_family = AF_INET6,
+               };
+
                vxlan_ip_miss(dev, &ipa);
        }