Commit d12d01d6 authored by Denis V. Lunev's avatar Denis V. Lunev Committed by David S. Miller
Browse files

[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: default avatarDenis V. Lunev <den@openvz.org>
Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4b3da706

include/net/net_namespace.h

+4 −0
Original line number Diff line number Diff line
@@ -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

net/packet/af_packet.c

+85 −46
Original line number Diff line number Diff line
@@ -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;

}

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