Commit 46f5182d authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv6: make in6_dump_addrs() lockless 



in6_dump_addrs() is called with RCU protection.

There is no need holding idev->lock to iterate through unicast addresses.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f0a7da70

net/ipv6/addrconf.c

+5 −9
Original line number Diff line number Diff line
@@ -5271,23 +5271,22 @@ static int inet6_fill_ifacaddr(struct sk_buff *skb, 
}



/* called with rcu_read_lock() */

static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,

static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,

			  struct netlink_callback *cb, int s_ip_idx,

			  struct inet6_fill_args *fillargs)

{

	struct ifmcaddr6 *ifmca;

	struct ifacaddr6 *ifaca;

	const struct ifmcaddr6 *ifmca;

	const struct ifacaddr6 *ifaca;

	int ip_idx = 0;

	int err = 1;



	read_lock_bh(&idev->lock);

	switch (fillargs->type) {

	case UNICAST_ADDR: {

		struct inet6_ifaddr *ifa;

		const struct inet6_ifaddr *ifa;

		fillargs->event = RTM_NEWADDR;



		/* unicast address incl. temp addr */

		list_for_each_entry(ifa, &idev->addr_list, if_list) {

		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {

			if (ip_idx < s_ip_idx)

				goto next;

			err = inet6_fill_ifaddr(skb, ifa, fillargs);
@@ -5300,7 +5299,6 @@ static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb, 
		break;

	}

	case MULTICAST_ADDR:

		read_unlock_bh(&idev->lock);

		fillargs->event = RTM_GETMULTICAST;



		/* multicast address */
@@ -5313,7 +5311,6 @@ static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb, 
			if (err < 0)

				break;

		}

		read_lock_bh(&idev->lock);

		break;

	case ANYCAST_ADDR:

		fillargs->event = RTM_GETANYCAST;
@@ -5330,7 +5327,6 @@ static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb, 
	default:

		break;

	}

	read_unlock_bh(&idev->lock);

	cb->args[2] = ip_idx;

	return err;

}