From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gao feng Subject: [PATCH V2] ipv6: Fix problem with expired dst cache Date: Mon, 27 Feb 2012 14:36:45 +0800 Message-ID: <1330324605-26617-1-git-send-email-gaofeng@cn.fujitsu.com> References: <1330064404-24763-1-git-send-email-gaofeng@cn.fujitsu.com> Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com, Gao feng To: davem@davemloft.net Return-path: Received: from cn.fujitsu.com ([222.73.24.84]:55343 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750811Ab2B0Gfx (ORCPT ); Mon, 27 Feb 2012 01:35:53 -0500 In-Reply-To: <1330064404-24763-1-git-send-email-gaofeng@cn.fujitsu.com> Sender: netdev-owner@vger.kernel.org List-ID: If the ipv6 dst cache which copy from the dst generated by ICMPV6 RA packet. this dst cache will not check expire because it has no RTF_EXPIRES flag. So this dst cache will always be used until the dst gc run. Change the struct dst_entry,add a union contains new pointer from and expires. When rt6_info.rt6i_flags has no RTF_EXPIRES flag,the dst.expires has no use. we can use this field to point to where the dst cache copy from. The dst.from is only used in IPV6. In func rt6_check_expired check if rt6_info.dst.from is expired. In func ip6_rt_copy only set dst.from when the ort has flag RTF_ADDRCONF and RTF_DEFAULT. Signed-off-by: Gao feng --- include/net/dst.h | 11 ++++++++++- net/ipv6/route.c | 22 +++++++++++++++++++--- 2 files changed, 29 insertions(+), 4 deletions(-) diff --git a/include/net/dst.h b/include/net/dst.h index 344c8dd..eae92f9 100644 --- a/include/net/dst.h +++ b/include/net/dst.h @@ -35,7 +35,16 @@ struct dst_entry { struct net_device *dev; struct dst_ops *ops; unsigned long _metrics; - unsigned long expires; + + union { + unsigned long expires; + /* + *from is used only for dst cache witch copy form + *the dst generated by ipv6 RA. + */ + void *from; + }; + struct dst_entry *path; struct neighbour __rcu *_neighbour; #ifdef CONFIG_XFRM diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 8c2e3ab..cd365fe 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -316,8 +316,18 @@ static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, static __inline__ int rt6_check_expired(const struct rt6_info *rt) { - return (rt->rt6i_flags & RTF_EXPIRES) && - time_after(jiffies, rt->dst.expires); + struct rt6_info *ort = NULL; + + if (rt->rt6i_flags & RTF_EXPIRES) { + if (time_after(jiffies, rt->dst.expires)) + return 1; + } else if (rt->dst.from) { + ort = (struct rt6_info *) rt->dst.from; + return (ort->rt6i_flags & RTF_EXPIRES) && + time_after(jiffies, ort->dst.expires); + } + + return 0; } static inline int rt6_need_strict(const struct in6_addr *daddr) @@ -608,6 +618,7 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, if (rt) { if (!addrconf_finite_timeout(lifetime)) { + rt->dst.expires = 0; rt->rt6i_flags &= ~RTF_EXPIRES; } else { rt->dst.expires = jiffies + HZ * lifetime; @@ -1799,7 +1810,12 @@ static struct rt6_info *ip6_rt_copy(const struct rt6_info *ort, if (rt->rt6i_idev) in6_dev_hold(rt->rt6i_idev); rt->dst.lastuse = jiffies; - rt->dst.expires = 0; + + if ((ort->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == + (RTF_ADDRCONF | RTF_DEFAULT)) + rt->dst.from = (void *)ort; + else + rt->dst.expires = 0; rt->rt6i_gateway = ort->rt6i_gateway; rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES; -- 1.7.5.4