[NETNS]: Process ARP in the context of the correct namespace.

Get namespace from a device and pass it to the routing engine. Enable
ARP packet processing and device notifiers after that.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 14 deletions

diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index efe01df8fc0e..6d90ec524212 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -242,7 +242,7 @@ static int arp_constructor(struct neighbour *neigh)
                 return -EINVAL;
         }
 
-        neigh->type = inet_addr_type(&init_net, addr);
+        neigh->type = inet_addr_type(dev->nd_net, addr);
 
         parms = in_dev->arp_parms;
         __neigh_parms_put(neigh->parms);
@@ -341,14 +341,14 @@ static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb)
         switch (IN_DEV_ARP_ANNOUNCE(in_dev)) {
         default:
         case 0:         /* By default announce any local IP */
-                if (skb && inet_addr_type(&init_net, ip_hdr(skb)->saddr) == RTN_LOCAL)
+                if (skb && inet_addr_type(dev->nd_net, ip_hdr(skb)->saddr) == RTN_LOCAL)
                         saddr = ip_hdr(skb)->saddr;
                 break;
         case 1:         /* Restrict announcements of saddr in same subnet */
                 if (!skb)
                         break;
                 saddr = ip_hdr(skb)->saddr;
-                if (inet_addr_type(&init_net, saddr) == RTN_LOCAL) {
+                if (inet_addr_type(dev->nd_net, saddr) == RTN_LOCAL) {
                         /* saddr should be known to target */
                         if (inet_addr_onlink(in_dev, target, saddr))
                                 break;
@@ -424,7 +424,7 @@ static int arp_filter(__be32 sip, __be32 tip, struct net_device *dev)
         int flag = 0;
         /*unsigned long now; */
 
-        if (ip_route_output_key(&init_net, &rt, &fl) < 0)
+        if (ip_route_output_key(dev->nd_net, &rt, &fl) < 0)
                 return 1;
         if (rt->u.dst.dev != dev) {
                 NET_INC_STATS_BH(LINUX_MIB_ARPFILTER);
@@ -477,7 +477,7 @@ int arp_find(unsigned char *haddr, struct sk_buff *skb)
 
         paddr = skb->rtable->rt_gateway;
 
-        if (arp_set_predefined(inet_addr_type(&init_net, paddr), haddr, paddr, dev))
+        if (arp_set_predefined(inet_addr_type(dev->nd_net, paddr), haddr, paddr, dev))
                 return 0;
 
         n = __neigh_lookup(&arp_tbl, &paddr, dev, 1);
@@ -709,6 +709,7 @@ static int arp_process(struct sk_buff *skb)
         u16 dev_type = dev->type;
         int addr_type;
         struct neighbour *n;
+        struct net *net = dev->nd_net;
 
         /* arp_rcv below verifies the ARP header and verifies the device
          * is ARP'able.
@@ -804,7 +805,7 @@ static int arp_process(struct sk_buff *skb)
         /* Special case: IPv4 duplicate address detection packet (RFC2131) */
         if (sip == 0) {
                 if (arp->ar_op == htons(ARPOP_REQUEST) &&
-                    inet_addr_type(&init_net, tip) == RTN_LOCAL &&
+                    inet_addr_type(net, tip) == RTN_LOCAL &&
                     !arp_ignore(in_dev, sip, tip))
                         arp_send(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha,
                                  dev->dev_addr, sha);
@@ -834,7 +835,7 @@ static int arp_process(struct sk_buff *skb)
                         goto out;
                 } else if (IN_DEV_FORWARD(in_dev)) {
                             if (addr_type == RTN_UNICAST  && rt->u.dst.dev != dev &&
-                             (arp_fwd_proxy(in_dev, rt) || pneigh_lookup(&arp_tbl, &init_net, &tip, dev, 0))) {
+                             (arp_fwd_proxy(in_dev, rt) || pneigh_lookup(&arp_tbl, net, &tip, dev, 0))) {
                                 n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
                                 if (n)
                                         neigh_release(n);
@@ -864,7 +865,7 @@ static int arp_process(struct sk_buff *skb)
                  */
                 if (n == NULL &&
                     arp->ar_op == htons(ARPOP_REPLY) &&
-                    inet_addr_type(&init_net, sip) == RTN_UNICAST)
+                    inet_addr_type(net, sip) == RTN_UNICAST)
                         n = __neigh_lookup(&arp_tbl, &sip, dev, 1);
         }
 
@@ -911,9 +912,6 @@ static int arp_rcv(struct sk_buff *skb, struct net_device *dev,
 {
         struct arphdr *arp;
 
-        if (dev->nd_net != &init_net)
-                goto freeskb;
-
         /* ARP header, plus 2 device addresses, plus 2 IP addresses.  */
         if (!pskb_may_pull(skb, arp_hdr_len(dev)))
                 goto freeskb;
@@ -1198,9 +1196,6 @@ static int arp_netdev_event(struct notifier_block *this, unsigned long event, vo
 {
         struct net_device *dev = ptr;
 
-        if (dev->nd_net != &init_net)
-                return NOTIFY_DONE;
-
         switch (event) {
         case NETDEV_CHANGEADDR:
                 neigh_changeaddr(&arp_tbl, dev);