From 8067bb8c1d3599e137dee445d65b64db90ebc6f5 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Sun, 7 Jan 2018 12:45:09 +0200 Subject: ipv6: Ignore dead routes during lookup Currently, dead routes are only present in the routing tables in case the 'ignore_routes_with_linkdown' sysctl is set. Otherwise, they are flushed. Subsequent patches are going to remove the reliance on this sysctl and make IPv6 more consistent with IPv4. Before this is done, we need to make sure dead routes are skipped during route lookup, so as to not cause packet loss. Signed-off-by: Ido Schimmel Acked-by: David Ahern Signed-off-by: David S. Miller --- net/ipv6/route.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) (limited to 'net/ipv6/route.c') diff --git a/net/ipv6/route.c b/net/ipv6/route.c index f980f904d6ea..c00156805bf0 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -474,6 +474,8 @@ static struct rt6_info *rt6_multipath_select(struct rt6_info *match, if (route_choosen == 0) { struct inet6_dev *idev = sibling->rt6i_idev; + if (sibling->rt6i_nh_flags & RTNH_F_DEAD) + break; if (sibling->rt6i_nh_flags & RTNH_F_LINKDOWN && idev->cnf.ignore_routes_with_linkdown) break; @@ -499,12 +501,15 @@ static inline struct rt6_info *rt6_device_match(struct net *net, struct rt6_info *local = NULL; struct rt6_info *sprt; - if (!oif && ipv6_addr_any(saddr)) - goto out; + if (!oif && ipv6_addr_any(saddr) && !(rt->rt6i_nh_flags & RTNH_F_DEAD)) + return rt; for (sprt = rt; sprt; sprt = rcu_dereference(sprt->rt6_next)) { struct net_device *dev = sprt->dst.dev; + if (sprt->rt6i_nh_flags & RTNH_F_DEAD) + continue; + if (oif) { if (dev->ifindex == oif) return sprt; @@ -533,8 +538,8 @@ static inline struct rt6_info *rt6_device_match(struct net *net, if (flags & RT6_LOOKUP_F_IFACE) return net->ipv6.ip6_null_entry; } -out: - return rt; + + return rt->rt6i_nh_flags & RTNH_F_DEAD ? net->ipv6.ip6_null_entry : rt; } #ifdef CONFIG_IPV6_ROUTER_PREF @@ -680,6 +685,9 @@ static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict, bool match_do_rr = false; struct inet6_dev *idev = rt->rt6i_idev; + if (rt->rt6i_nh_flags & RTNH_F_DEAD) + goto out; + if (idev->cnf.ignore_routes_with_linkdown && rt->rt6i_nh_flags & RTNH_F_LINKDOWN && !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE)) @@ -2153,6 +2161,8 @@ static struct rt6_info *__ip6_route_redirect(struct net *net, fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); restart: for_each_fib6_node_rt_rcu(fn) { + if (rt->rt6i_nh_flags & RTNH_F_DEAD) + continue; if (rt6_check_expired(rt)) continue; if (rt->dst.error) -- cgit v1.2.3