Commit 8723e1b4 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

inet: RCU changes in inetdev_by_index() 



Convert inetdev_by_index() to not increment in_dev refcount.

Callers hold RCU or RTNL, and should not decrement in_dev refcount.

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9e917dca

net/ipv4/devinet.c

+4 −3
Original line number Diff line number Diff line
@@ -403,6 +403,9 @@ static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa) 
	return inet_insert_ifa(ifa);

}



/* Caller must hold RCU or RTNL :

 * We dont take a reference on found in_device

 */

struct in_device *inetdev_by_index(struct net *net, int ifindex)

{

	struct net_device *dev;
@@ -411,7 +414,7 @@ struct in_device *inetdev_by_index(struct net *net, int ifindex) 
	rcu_read_lock();

	dev = dev_get_by_index_rcu(net, ifindex);

	if (dev)

		in_dev = in_dev_get(dev);

		in_dev = rcu_dereference_rtnl(dev->ip_ptr);

	rcu_read_unlock();

	return in_dev;

}
@@ -453,8 +456,6 @@ static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg 
		goto errout;

	}



	__in_dev_put(in_dev);



	for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;

	     ifap = &ifa->ifa_next) {

		if (tb[IFA_LOCAL] &&

net/ipv4/fib_semantics.c

+11 −14
Original line number Diff line number Diff line
@@ -590,32 +590,29 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, 
		if (!dev)

			goto out;

		dev_hold(dev);

		err = -ENETDOWN;

		if (!(dev->flags & IFF_UP))

			goto out;

		err = 0;

out:

		rcu_read_unlock();

		return err;

		err = (dev->flags & IFF_UP) ? 0 : -ENETDOWN;

	} else {

		struct in_device *in_dev;



		if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK))

			return -EINVAL;



		rcu_read_lock();

		err = -ENODEV;

		in_dev = inetdev_by_index(net, nh->nh_oif);

		if (in_dev == NULL)

			return -ENODEV;

		if (!(in_dev->dev->flags & IFF_UP)) {

			in_dev_put(in_dev);

			return -ENETDOWN;

		}

			goto out;

		err = -ENETDOWN;

		if (!(in_dev->dev->flags & IFF_UP))

			goto out;

		nh->nh_dev = in_dev->dev;

		dev_hold(nh->nh_dev);

		nh->nh_scope = RT_SCOPE_HOST;

		in_dev_put(in_dev);

		err = 0;

	}

	return 0;

out:

	rcu_read_unlock();

	return err;

}



static inline unsigned int fib_laddr_hashfn(__be32 val)

net/ipv4/igmp.c

+0 −2
Original line number Diff line number Diff line
@@ -1429,8 +1429,6 @@ static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr) 


	if (imr->imr_ifindex) {

		idev = inetdev_by_index(net, imr->imr_ifindex);

		if (idev)

			__in_dev_put(idev);

		return idev;

	}

	if (imr->imr_address.s_addr) {

net/ipv4/ip_gre.c

+1 −3
Original line number Diff line number Diff line
@@ -1245,10 +1245,8 @@ static int ipgre_close(struct net_device *dev) 
	if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {

		struct in_device *in_dev;

		in_dev = inetdev_by_index(dev_net(dev), t->mlink);

		if (in_dev) {

		if (in_dev)

			ip_mc_dec_group(in_dev, t->parms.iph.daddr);

			in_dev_put(in_dev);

		}

	}

	return 0;

}