Commit fd5c0027 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv6: avoid dev_hold()/dev_put() in rawv6_bind() 



Using RCU helps not touching device refcount in rawv6_bind()

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 18294ad1

net/ipv6/raw.c

+11 −12
Original line number Diff line number Diff line
@@ -249,7 +249,7 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 


	/* Raw sockets are IPv6 only */

	if (addr_type == IPV6_ADDR_MAPPED)

		return(-EADDRNOTAVAIL);

		return -EADDRNOTAVAIL;



	lock_sock(sk);
@@ -257,6 +257,7 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 
	if (sk->sk_state != TCP_CLOSE)

		goto out;



	rcu_read_lock();

	/* Check if the address belongs to the host. */

	if (addr_type != IPV6_ADDR_ANY) {

		struct net_device *dev = NULL;
@@ -272,13 +273,13 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 


			/* Binding to link-local address requires an interface */

			if (!sk->sk_bound_dev_if)

				goto out;

				goto out_unlock;



			dev = dev_get_by_index(sock_net(sk), sk->sk_bound_dev_if);

			if (!dev) {

			err = -ENODEV;

				goto out;

			}

			dev = dev_get_by_index_rcu(sock_net(sk),

						   sk->sk_bound_dev_if);

			if (!dev)

				goto out_unlock;

		}



		/* ipv4 addr of the socket is invalid.  Only the
@@ -289,13 +290,9 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 
			err = -EADDRNOTAVAIL;

			if (!ipv6_chk_addr(sock_net(sk), &addr->sin6_addr,

					   dev, 0)) {

				if (dev)

					dev_put(dev);

				goto out;

				goto out_unlock;

			}

		}

		if (dev)

			dev_put(dev);

	}



	inet->inet_rcv_saddr = inet->inet_saddr = v4addr;
@@ -303,6 +300,8 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 
	if (!(addr_type & IPV6_ADDR_MULTICAST))

		ipv6_addr_copy(&np->saddr, &addr->sin6_addr);

	err = 0;

out_unlock:

	rcu_read_unlock();

out:

	release_sock(sk);

	return err;