Commit 84f59370 authored Apr 03, 2008 by Denis V. Lunev Committed by David S. Miller Apr 03, 2008

[IPV6]: Fix refcounting for anycast dst entries.



Anycast DST entries allocated inside ipv6_dev_ac_inc are leaked when
network device is stopped without removing IPv6 addresses from it. The
bug has been observed in the reality on 2.6.18-rhel5 kernel.

In the above case addrconf_ifdown marks all entries as obsolete and
ip6_del_rt called from __ipv6_dev_ac_dec returns ENOENT. The
referrence is not dropped.

The fix is simple. DST entry should not keep referrence when stored in
the FIB6 tree.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent eb867579

net/ipv6/anycast.c

+2 −7

Original line number	Diff line number	Diff line
		@@ -334,9 +334,7 @@ int ipv6_dev_ac_inc(struct net_device dev, struct in6_addr addr)
		idev->ac_list = aca;
		write_unlock_bh(&idev->lock);

		dst_hold(&rt->u.dst);
		if (ip6_ins_rt(rt))
		dst_release(&rt->u.dst);
		ip6_ins_rt(rt);

		addrconf_join_solict(dev, &aca->aca_addr);

		@@ -378,10 +376,7 @@ int __ipv6_dev_ac_dec(struct inet6_dev idev, struct in6_addr addr)
		addrconf_leave_solict(idev, &aca->aca_addr);

		dst_hold(&aca->aca_rt->u.dst);
		if (ip6_del_rt(aca->aca_rt))
		dst_free(&aca->aca_rt->u.dst);
		else
		dst_release(&aca->aca_rt->u.dst);
		ip6_del_rt(aca->aca_rt);

		aca_put(aca);
		return 0;

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