This is a note to let you know that I've just added the patch titled
ipv4: fix sending of redirects
to the 3.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ipv4-fix-sending-of-redirects.patch
and it can be found in the queue-3.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From 9412e270cddca255cb5dc3e28d36fc8c32eaec95 Mon Sep 17 00:00:00 2001
From: Julian Anastasov <[email protected]>
Date: Mon, 8 Oct 2012 11:41:15 +0000
Subject: ipv4: fix sending of redirects
From: Julian Anastasov <[email protected]>
[ Upstream commit e81da0e113a1b7fc7449ae6213f65f89ccac6d06 ]
After "Cache input routes in fib_info nexthops" (commit
d2d68ba9fe) and "Elide fib_validate_source() completely when possible"
(commit 7a9bc9b81a) we can not send ICMP redirects. It seems we
should not cache the RTCF_DOREDIRECT flag in nh_rth_input because
the same fib_info can be used for traffic that is not redirected,
eg. from other input devices or from sources that are not in same subnet.
As result, we have to disable the caching of RTCF_DOREDIRECT
flag and to force source validation for the case when forwarding
traffic to the input device. If traffic comes from directly connected
source we allow redirection as it was done before both changes.
Avoid setting RTCF_DOREDIRECT if IN_DEV_TX_REDIRECTS
is disabled, this can avoid source address validation and to
help caching the routes.
After the change "Adjust semantics of rt->rt_gateway"
(commit f8126f1d51) we should make sure our ICMP_REDIR_HOST messages
contain daddr instead of 0.0.0.0 when target is directly connected.
Signed-off-by: Julian Anastasov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
net/ipv4/fib_frontend.c | 3 ++-
net/ipv4/route.c | 30 ++++++++++++++++--------------
2 files changed, 18 insertions(+), 15 deletions(-)
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -322,7 +322,8 @@ int fib_validate_source(struct sk_buff *
{
int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev);
- if (!r && !fib_num_tclassid_users(dev_net(dev))) {
+ if (!r && !fib_num_tclassid_users(dev_net(dev)) &&
+ (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) {
*itag = 0;
return 0;
}
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -802,7 +802,8 @@ void ip_rt_send_redirect(struct sk_buff
net = dev_net(rt->dst.dev);
peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
if (!peer) {
- icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
+ icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST,
+ rt_nexthop(rt, ip_hdr(skb)->daddr));
return;
}
@@ -827,7 +828,9 @@ void ip_rt_send_redirect(struct sk_buff
time_after(jiffies,
(peer->rate_last +
(ip_rt_redirect_load << peer->rate_tokens)))) {
- icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
+ __be32 gw = rt_nexthop(rt, ip_hdr(skb)->daddr);
+
+ icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, gw);
peer->rate_last = jiffies;
++peer->rate_tokens;
#ifdef CONFIG_IP_ROUTE_VERBOSE
@@ -835,7 +838,7 @@ void ip_rt_send_redirect(struct sk_buff
peer->rate_tokens == ip_rt_redirect_number)
net_warn_ratelimited("host %pI4/if%d ignores redirects
for %pI4 to %pI4\n",
&ip_hdr(skb)->saddr, inet_iif(skb),
- &ip_hdr(skb)->daddr,
&rt->rt_gateway);
+ &ip_hdr(skb)->daddr, &gw);
#endif
}
out_put_peer:
@@ -1445,10 +1448,13 @@ static int __mkroute_input(struct sk_buf
goto cleanup;
}
- if (out_dev == in_dev && err &&
+ do_cache = res->fi && !itag;
+ if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) &&
(IN_DEV_SHARED_MEDIA(out_dev) ||
- inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
+ inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) {
flags |= RTCF_DOREDIRECT;
+ do_cache = false;
+ }
if (skb->protocol != htons(ETH_P_IP)) {
/* Not IP (i.e. ARP). Do not create route, if it is
@@ -1465,15 +1471,11 @@ static int __mkroute_input(struct sk_buf
}
}
- do_cache = false;
- if (res->fi) {
- if (!itag) {
- rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
- if (rt_cache_valid(rth)) {
- skb_dst_set_noref(skb, &rth->dst);
- goto out;
- }
- do_cache = true;
+ if (do_cache) {
+ rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
+ if (rt_cache_valid(rth)) {
+ skb_dst_set_noref(skb, &rth->dst);
+ goto out;
}
}
Patches currently in stable-queue which might be from [email protected] are
queue-3.6/ipv4-fix-sending-of-redirects.patch
queue-3.6/ipvs-fix-arp-resolving-for-direct-routing-mode.patch
queue-3.6/ipv4-add-flowi_flag_known_nh.patch
queue-3.6/ipv4-fix-forwarding-for-strict-source-routes.patch
queue-3.6/ipv4-make-sure-nh_pcpu_rth_output-is-always-allocated.patch
queue-3.6/ipv4-introduce-rt_uses_gateway.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
