From 95cb5745983c222867cc9ac593aebb2ad67d72c0 Mon Sep 17 00:00:00 2001 From: Dmitry Popov Date: Tue, 29 Jul 2014 03:07:52 +0400 Subject: [PATCH] ip_tunnel(ipv4): fix tunnels with "local any remote $remote_ip" Ipv4 tunnels created with "local any remote $ip" didn't work properly since 7d442fab0 (ipv4: Cache dst in tunnels). 99% of packets sent via those tunnels had src addr = 0.0.0.0. That was because only dst_entry was cached, although fl4.saddr has to be cached too. Every time ip_tunnel_xmit used cached dst_entry (tunnel_rtable_get returned non-NULL), fl4.saddr was initialized with tnl_params->saddr (= 0 in our case), and wasn't changed until iptunnel_xmit(). This patch adds saddr to ip_tunnel->dst_cache, fixing this issue. Reported-by: Sergey Popov Signed-off-by: Dmitry Popov Signed-off-by: David S. Miller --- include/net/ip_tunnels.h | 1 + net/ipv4/ip_tunnel.c | 29 ++++++++++++++++++----------- 2 files changed, 19 insertions(+), 11 deletions(-) diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h index a4daf9eb8562..8dd8cab88b87 100644 --- a/include/net/ip_tunnels.h +++ b/include/net/ip_tunnels.h @@ -40,6 +40,7 @@ struct ip_tunnel_prl_entry { struct ip_tunnel_dst { struct dst_entry __rcu *dst; + __be32 saddr; }; struct ip_tunnel { diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 6f9de61dce5f..45920d928341 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -69,23 +69,25 @@ static unsigned int ip_tunnel_hash(__be32 key, __be32 remote) } static void __tunnel_dst_set(struct ip_tunnel_dst *idst, - struct dst_entry *dst) + struct dst_entry *dst, __be32 saddr) { struct dst_entry *old_dst; dst_clone(dst); old_dst = xchg((__force struct dst_entry **)&idst->dst, dst); dst_release(old_dst); + idst->saddr = saddr; } -static void tunnel_dst_set(struct ip_tunnel *t, struct dst_entry *dst) +static void tunnel_dst_set(struct ip_tunnel *t, + struct dst_entry *dst, __be32 saddr) { - __tunnel_dst_set(this_cpu_ptr(t->dst_cache), dst); + __tunnel_dst_set(this_cpu_ptr(t->dst_cache), dst, saddr); } static void tunnel_dst_reset(struct ip_tunnel *t) { - tunnel_dst_set(t, NULL); + tunnel_dst_set(t, NULL, 0); } void ip_tunnel_dst_reset_all(struct ip_tunnel *t) @@ -93,20 +95,25 @@ void ip_tunnel_dst_reset_all(struct ip_tunnel *t) int i; for_each_possible_cpu(i) - __tunnel_dst_set(per_cpu_ptr(t->dst_cache, i), NULL); + __tunnel_dst_set(per_cpu_ptr(t->dst_cache, i), NULL, 0); } EXPORT_SYMBOL(ip_tunnel_dst_reset_all); -static struct rtable *tunnel_rtable_get(struct ip_tunnel *t, u32 cookie) +static struct rtable *tunnel_rtable_get(struct ip_tunnel *t, + u32 cookie, __be32 *saddr) { + struct ip_tunnel_dst *idst; struct dst_entry *dst; rcu_read_lock(); - dst = rcu_dereference(this_cpu_ptr(t->dst_cache)->dst); + idst = this_cpu_ptr(t->dst_cache); + dst = rcu_dereference(idst->dst); if (dst && !atomic_inc_not_zero(&dst->__refcnt)) dst = NULL; if (dst) { - if (dst->obsolete && dst->ops->check(dst, cookie) == NULL) { + if (!dst->obsolete || dst->ops->check(dst, cookie)) { + *saddr = idst->saddr; + } else { tunnel_dst_reset(t); dst_release(dst); dst = NULL; @@ -367,7 +374,7 @@ static int ip_tunnel_bind_dev(struct net_device *dev) if (!IS_ERR(rt)) { tdev = rt->dst.dev; - tunnel_dst_set(tunnel, &rt->dst); + tunnel_dst_set(tunnel, &rt->dst, fl4.saddr); ip_rt_put(rt); } if (dev->type != ARPHRD_ETHER) @@ -610,7 +617,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, init_tunnel_flow(&fl4, protocol, dst, tnl_params->saddr, tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link); - rt = connected ? tunnel_rtable_get(tunnel, 0) : NULL; + rt = connected ? tunnel_rtable_get(tunnel, 0, &fl4.saddr) : NULL; if (!rt) { rt = ip_route_output_key(tunnel->net, &fl4); @@ -620,7 +627,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, goto tx_error; } if (connected) - tunnel_dst_set(tunnel, &rt->dst); + tunnel_dst_set(tunnel, &rt->dst, fl4.saddr); } if (rt->dst.dev == dev) {