[NET]: Make AF_PACKET handle multiple network namespaces

This is done by making packet_sklist_lock and packet_sklist per
network namespace and adding an additional filter condition on
received packets to ensure they came from the proper network
namespace.

Changes from v1:
- prohibit to call inet_dgram_ops.ioctl in other than init_net

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 90802a6..4d0d634 100644 (file)
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -32,6 +32,10 @@ struct net {
        struct hlist_head       *dev_index_head;
 
        struct sock             *rtnl;                  /* rtnetlink socket */
+
+       /* List of all packet sockets. */
+       rwlock_t                packet_sklist_lock;
+       struct hlist_head       packet_sklist;
 };
 
 #ifdef CONFIG_NET

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 8a7807d..45e3cbc 100644 (file)
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -135,10 +135,6 @@ dev->hard_header == NULL (ll header is added by device, we cannot control it)
    packet classifier depends on it.
  */
 
-/* List of all packet sockets. */
-static HLIST_HEAD(packet_sklist);
-static DEFINE_RWLOCK(packet_sklist_lock);
-
 /* Private packet socket structures. */
 
 struct packet_mclist
@@ -246,9 +242,6 @@ static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,  struct
        struct sock *sk;
        struct sockaddr_pkt *spkt;
 
-       if (dev->nd_net != &init_net)
-               goto out;
-
        /*
         *      When we registered the protocol we saved the socket in the data
         *      field for just this event.
@@ -270,6 +263,9 @@ static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,  struct
        if (skb->pkt_type == PACKET_LOOPBACK)
                goto out;
 
+       if (dev->nd_net != sk->sk_net)
+               goto out;
+
        if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
                goto oom;
 
@@ -341,7 +337,7 @@ static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
         */
 
        saddr->spkt_device[13] = 0;
-       dev = dev_get_by_name(&init_net, saddr->spkt_device);
+       dev = dev_get_by_name(sk->sk_net, saddr->spkt_device);
        err = -ENODEV;
        if (dev == NULL)
                goto out_unlock;
@@ -449,15 +445,15 @@ static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet
        int skb_len = skb->len;
        unsigned int snaplen, res;
 
-       if (dev->nd_net != &init_net)
-               goto drop;
-
        if (skb->pkt_type == PACKET_LOOPBACK)
                goto drop;
 
        sk = pt->af_packet_priv;
        po = pkt_sk(sk);
 
+       if (dev->nd_net != sk->sk_net)
+               goto drop;
+
        skb->dev = dev;
 
        if (dev->header_ops) {
@@ -566,15 +562,15 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe
        struct sk_buff *copy_skb = NULL;
        struct timeval tv;
 
-       if (dev->nd_net != &init_net)
-               goto drop;
-
        if (skb->pkt_type == PACKET_LOOPBACK)
                goto drop;
 
        sk = pt->af_packet_priv;
        po = pkt_sk(sk);
 
+       if (dev->nd_net != sk->sk_net)
+               goto drop;
+
        if (dev->header_ops) {
                if (sk->sk_type != SOCK_DGRAM)
                        skb_push(skb, skb->data - skb_mac_header(skb));
@@ -732,7 +728,7 @@ static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
        }
 
 
-       dev = dev_get_by_index(&init_net, ifindex);
+       dev = dev_get_by_index(sk->sk_net, ifindex);
        err = -ENXIO;
        if (dev == NULL)
                goto out_unlock;
@@ -799,15 +795,17 @@ static int packet_release(struct socket *sock)
 {
        struct sock *sk = sock->sk;
        struct packet_sock *po;
+       struct net *net;
 
        if (!sk)
                return 0;
 
+       net = sk->sk_net;
        po = pkt_sk(sk);
 
-       write_lock_bh(&packet_sklist_lock);
+       write_lock_bh(&net->packet_sklist_lock);
        sk_del_node_init(sk);
-       write_unlock_bh(&packet_sklist_lock);
+       write_unlock_bh(&net->packet_sklist_lock);
 
        /*
         *      Unhook packet receive handler.
@@ -916,7 +914,7 @@ static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int add
                return -EINVAL;
        strlcpy(name,uaddr->sa_data,sizeof(name));
 
-       dev = dev_get_by_name(&init_net, name);
+       dev = dev_get_by_name(sk->sk_net, name);
        if (dev) {
                err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
                dev_put(dev);
@@ -943,7 +941,7 @@ static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len
 
        if (sll->sll_ifindex) {
                err = -ENODEV;
-               dev = dev_get_by_index(&init_net, sll->sll_ifindex);
+               dev = dev_get_by_index(sk->sk_net, sll->sll_ifindex);
                if (dev == NULL)
                        goto out;
        }
@@ -972,9 +970,6 @@ static int packet_create(struct net *net, struct socket *sock, int protocol)
        __be16 proto = (__force __be16)protocol; /* weird, but documented */
        int err;
 
-       if (net != &init_net)
-               return -EAFNOSUPPORT;
-
        if (!capable(CAP_NET_RAW))
                return -EPERM;
        if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
@@ -1020,9 +1015,9 @@ static int packet_create(struct net *net, struct socket *sock, int protocol)
                po->running = 1;
        }
 
-       write_lock_bh(&packet_sklist_lock);
-       sk_add_node(sk, &packet_sklist);
-       write_unlock_bh(&packet_sklist_lock);
+       write_lock_bh(&net->packet_sklist_lock);
+       sk_add_node(sk, &net->packet_sklist);
+       write_unlock_bh(&net->packet_sklist_lock);
        return(0);
 out:
        return err;
@@ -1140,7 +1135,7 @@ static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
                return -EOPNOTSUPP;
 
        uaddr->sa_family = AF_PACKET;
-       dev = dev_get_by_index(&init_net, pkt_sk(sk)->ifindex);
+       dev = dev_get_by_index(sk->sk_net, pkt_sk(sk)->ifindex);
        if (dev) {
                strlcpy(uaddr->sa_data, dev->name, 15);
                dev_put(dev);
@@ -1165,7 +1160,7 @@ static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
        sll->sll_family = AF_PACKET;
        sll->sll_ifindex = po->ifindex;
        sll->sll_protocol = po->num;
-       dev = dev_get_by_index(&init_net, po->ifindex);
+       dev = dev_get_by_index(sk->sk_net, po->ifindex);
        if (dev) {
                sll->sll_hatype = dev->type;
                sll->sll_halen = dev->addr_len;
@@ -1217,7 +1212,7 @@ static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
        rtnl_lock();
 
        err = -ENODEV;
-       dev = __dev_get_by_index(&init_net, mreq->mr_ifindex);
+       dev = __dev_get_by_index(sk->sk_net, mreq->mr_ifindex);
        if (!dev)
                goto done;
 
@@ -1271,7 +1266,7 @@ static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
                        if (--ml->count == 0) {
                                struct net_device *dev;
                                *mlp = ml->next;
-                               dev = dev_get_by_index(&init_net, ml->ifindex);
+                               dev = dev_get_by_index(sk->sk_net, ml->ifindex);
                                if (dev) {
                                        packet_dev_mc(dev, ml, -1);
                                        dev_put(dev);
@@ -1299,7 +1294,7 @@ static void packet_flush_mclist(struct sock *sk)
                struct net_device *dev;
 
                po->mclist = ml->next;
-               if ((dev = dev_get_by_index(&init_net, ml->ifindex)) != NULL) {
+               if ((dev = dev_get_by_index(sk->sk_net, ml->ifindex)) != NULL) {
                        packet_dev_mc(dev, ml, -1);
                        dev_put(dev);
                }
@@ -1455,12 +1450,10 @@ static int packet_notifier(struct notifier_block *this, unsigned long msg, void
        struct sock *sk;
        struct hlist_node *node;
        struct net_device *dev = data;
+       struct net *net = dev->nd_net;
 
-       if (dev->nd_net != &init_net)
-               return NOTIFY_DONE;
-
-       read_lock(&packet_sklist_lock);
-       sk_for_each(sk, node, &packet_sklist) {
+       read_lock(&net->packet_sklist_lock);
+       sk_for_each(sk, node, &net->packet_sklist) {
                struct packet_sock *po = pkt_sk(sk);
 
                switch (msg) {
@@ -1499,7 +1492,7 @@ static int packet_notifier(struct notifier_block *this, unsigned long msg, void
                        break;
                }
        }
-       read_unlock(&packet_sklist_lock);
+       read_unlock(&net->packet_sklist_lock);
        return NOTIFY_DONE;
 }
 
@@ -1547,6 +1540,8 @@ static int packet_ioctl(struct socket *sock, unsigned int cmd,
                case SIOCGIFDSTADDR:
                case SIOCSIFDSTADDR:
                case SIOCSIFFLAGS:
+                       if (sk->sk_net != &init_net)
+                               return -ENOIOCTLCMD;
                        return inet_dgram_ops.ioctl(sock, cmd, arg);
 #endif
 
@@ -1862,12 +1857,12 @@ static struct notifier_block packet_netdev_notifier = {
 };
 
 #ifdef CONFIG_PROC_FS
-static inline struct sock *packet_seq_idx(loff_t off)
+static inline struct sock *packet_seq_idx(struct net *net, loff_t off)
 {
        struct sock *s;
        struct hlist_node *node;
 
-       sk_for_each(s, node, &packet_sklist) {
+       sk_for_each(s, node, &net->packet_sklist) {
                if (!off--)
                        return s;
        }
@@ -1876,21 +1871,24 @@ static inline struct sock *packet_seq_idx(loff_t off)
 
 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
 {
-       read_lock(&packet_sklist_lock);
-       return *pos ? packet_seq_idx(*pos - 1) : SEQ_START_TOKEN;
+       struct net *net = seq->private;
+       read_lock(&net->packet_sklist_lock);
+       return *pos ? packet_seq_idx(net, *pos - 1) : SEQ_START_TOKEN;
 }
 
 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
+       struct net *net = seq->private;
        ++*pos;
        return  (v == SEQ_START_TOKEN)
-               ? sk_head(&packet_sklist)
+               ? sk_head(&net->packet_sklist)
                : sk_next((struct sock*)v) ;
 }
 
 static void packet_seq_stop(struct seq_file *seq, void *v)
 {
-       read_unlock(&packet_sklist_lock);
+       struct net *net = seq->private;
+       read_unlock(&net->packet_sklist_lock);
 }
 
 static int packet_seq_show(struct seq_file *seq, void *v)
@@ -1926,7 +1924,26 @@ static const struct seq_operations packet_seq_ops = {
 
 static int packet_seq_open(struct inode *inode, struct file *file)
 {
-       return seq_open(file, &packet_seq_ops);
+       struct seq_file *seq;
+       int res;
+       res = seq_open(file, &packet_seq_ops);
+       if (!res) {
+               seq = file->private_data;
+               seq->private = get_proc_net(inode);
+               if (!seq->private) {
+                       seq_release(inode, file);
+                       res = -ENXIO;
+               }
+       }
+       return res;
+}
+
+static int packet_seq_release(struct inode *inode, struct file *file)
+{
+       struct seq_file *seq=  file->private_data;
+       struct net *net = seq->private;
+       put_net(net);
+       return seq_release(inode, file);
 }
 
 static const struct file_operations packet_seq_fops = {
@@ -1934,15 +1951,37 @@ static const struct file_operations packet_seq_fops = {
        .open           = packet_seq_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
-       .release        = seq_release,
+       .release        = packet_seq_release,
 };
 
 #endif
 
+static int packet_net_init(struct net *net)
+{
+       rwlock_init(&net->packet_sklist_lock);
+       INIT_HLIST_HEAD(&net->packet_sklist);
+
+       if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
+               return -ENOMEM;
+
+       return 0;
+}
+
+static void packet_net_exit(struct net *net)
+{
+       proc_net_remove(net, "packet");
+}
+
+static struct pernet_operations packet_net_ops = {
+       .init = packet_net_init,
+       .exit = packet_net_exit,
+};
+
+
 static void __exit packet_exit(void)
 {
-       proc_net_remove(&init_net, "packet");
        unregister_netdevice_notifier(&packet_netdev_notifier);
+       unregister_pernet_subsys(&packet_net_ops);
        sock_unregister(PF_PACKET);
        proto_unregister(&packet_proto);
 }
@@ -1955,8 +1994,8 @@ static int __init packet_init(void)
                goto out;
 
        sock_register(&packet_family_ops);
+       register_pernet_subsys(&packet_net_ops);
        register_netdevice_notifier(&packet_netdev_notifier);
-       proc_net_fops_create(&init_net, "packet", 0, &packet_seq_fops);
 out:
        return rc;
 }