[NET]: Make rtnetlink infrastructure network namespace aware (v3)

[mv-sheeva.git] / net / core / rtnetlink.c

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 4edc3dac4ccdf98459918e5736bb6a708d378925..9efaf35934f4078552f8c6a39260a3832865ef68 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -60,7 +60,6 @@ struct rtnl_link
 };
 
 static DEFINE_MUTEX(rtnl_mutex);
-static struct sock *rtnl;
 
 void rtnl_lock(void)
 {
@@ -458,8 +457,9 @@ size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
        return ret;
 }
 
-int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
+int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, unsigned group, int echo)
 {
+       struct sock *rtnl = net->rtnl;
        int err = 0;
 
        NETLINK_CB(skb).dst_group = group;
@@ -471,14 +471,17 @@ int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
        return err;
 }
 
-int rtnl_unicast(struct sk_buff *skb, u32 pid)
+int rtnl_unicast(struct sk_buff *skb, struct net *net, u32 pid)
 {
+       struct sock *rtnl = net->rtnl;
+
        return nlmsg_unicast(rtnl, skb, pid);
 }
 
-int rtnl_notify(struct sk_buff *skb, u32 pid, u32 group,
+int rtnl_notify(struct sk_buff *skb, struct net *net, u32 pid, u32 group,
                struct nlmsghdr *nlh, gfp_t flags)
 {
+       struct sock *rtnl = net->rtnl;
        int report = 0;
 
        if (nlh)
@@ -487,8 +490,10 @@ int rtnl_notify(struct sk_buff *skb, u32 pid, u32 group,
        return nlmsg_notify(rtnl, skb, pid, group, report, flags);
 }
 
-void rtnl_set_sk_err(u32 group, int error)
+void rtnl_set_sk_err(struct net *net, u32 group, int error)
 {
+       struct sock *rtnl = net->rtnl;
+
        netlink_set_err(rtnl, 0, group, error);
 }
 
@@ -1201,7 +1206,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
                kfree_skb(nskb);
                goto errout;
        }
-       err = rtnl_unicast(nskb, NETLINK_CB(skb).pid);
+       err = rtnl_unicast(nskb, net, NETLINK_CB(skb).pid);
 errout:
        dev_put(dev);
 
@@ -1252,10 +1257,10 @@ void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
                kfree_skb(skb);
                goto errout;
        }
-       err = rtnl_notify(skb, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
+       err = rtnl_notify(skb, &init_net, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
 errout:
        if (err < 0)
-               rtnl_set_sk_err(RTNLGRP_LINK, err);
+               rtnl_set_sk_err(&init_net, RTNLGRP_LINK, err);
 }
 
 /* Protected by RTNL sempahore.  */
@@ -1266,6 +1271,7 @@ static int rtattr_max;
 
 static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
+       struct net *net = skb->sk->sk_net;
        rtnl_doit_func doit;
        int sz_idx, kind;
        int min_len;
@@ -1294,6 +1300,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                return -EPERM;
 
        if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
+               struct sock *rtnl;
                rtnl_dumpit_func dumpit;
 
                dumpit = rtnl_get_dumpit(family, type);
@@ -1301,6 +1308,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                        return -EOPNOTSUPP;
 
                __rtnl_unlock();
+               rtnl = net->rtnl;
                err = netlink_dump_start(rtnl, skb, nlh, dumpit, NULL);
                rtnl_lock();
                return err;
@@ -1373,6 +1381,40 @@ static struct notifier_block rtnetlink_dev_notifier = {
        .notifier_call  = rtnetlink_event,
 };
 
+
+static int rtnetlink_net_init(struct net *net)
+{
+       struct sock *sk;
+       sk = netlink_kernel_create(net, NETLINK_ROUTE, RTNLGRP_MAX,
+                                  rtnetlink_rcv, &rtnl_mutex, THIS_MODULE);
+       if (!sk)
+               return -ENOMEM;
+
+       /* Don't hold an extra reference on the namespace */
+       put_net(sk->sk_net);
+       net->rtnl = sk;
+       return 0;
+}
+
+static void rtnetlink_net_exit(struct net *net)
+{
+       struct sock *sk = net->rtnl;
+       if (sk) {
+               /* At the last minute lie and say this is a socket for the
+                * initial network namespace.  So the socket will be safe to
+                * free.
+                */
+               sk->sk_net = get_net(&init_net);
+               sock_put(sk);
+               net->rtnl = NULL;
+       }
+}
+
+static struct pernet_operations rtnetlink_net_ops = {
+       .init = rtnetlink_net_init,
+       .exit = rtnetlink_net_exit,
+};
+
 void __init rtnetlink_init(void)
 {
        int i;
@@ -1385,10 +1427,9 @@ void __init rtnetlink_init(void)
        if (!rta_buf)
                panic("rtnetlink_init: cannot allocate rta_buf\n");
 
-       rtnl = netlink_kernel_create(&init_net, NETLINK_ROUTE, RTNLGRP_MAX,
-                                    rtnetlink_rcv, &rtnl_mutex, THIS_MODULE);
-       if (rtnl == NULL)
+       if (register_pernet_subsys(&rtnetlink_net_ops))
                panic("rtnetlink_init: cannot initialize rtnetlink\n");
+
        netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
        register_netdevice_notifier(&rtnetlink_dev_notifier);