From: Wei Wang <wei...@google.com>
When ICMPV6_PKT_TOOBIG message is received by a connected UDP socket,
the new mtu value is not properly updated in the dst_entry associated
with the socket.
This leads to the issue that the mtu value returned by getsockopt(sockfd,
IPPROTO_IPV6, IPV6_MTU, ...) is wrong.
The fix is to update sk->sk_dst_cache and other corresponding fields
when a new routing cache is allocated for the new pmtu in UDP connected
socket case.
Signed-off-by: Wei Wang <wei...@google.com>
---
include/net/ip6_route.h | 4 ++--
net/ipv6/ah6.c | 2 +-
net/ipv6/esp6.c | 2 +-
net/ipv6/icmp.c | 2 +-
net/ipv6/ip6_vti.c | 2 +-
net/ipv6/ipcomp6.c | 2 +-
net/ipv6/route.c | 21 +++++++++------------
7 files changed, 16 insertions(+), 19 deletions(-)
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 295d291..2b147a8 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -115,8 +115,8 @@ void rt6_purge_dflt_routers(struct net *net);
int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
const struct in6_addr *gwaddr);
-void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
- u32 mark);
+void ip6_update_pmtu(struct net *net, struct sock *sk, struct sk_buff *skb,
+ __be32 mtu, int oif, u32 mark);
void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark);
void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 0630a4d5..2c926ec 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -664,7 +664,7 @@ static int ah6_err(struct sk_buff *skb, struct
inet6_skb_parm *opt,
if (type == NDISC_REDIRECT)
ip6_redirect(skb, net, skb->dev->ifindex, 0);
else
- ip6_update_pmtu(skb, net, info, 0, 0);
+ ip6_update_pmtu(net, NULL, skb, info, 0, 0);
xfrm_state_put(x);
return 0;
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 060a60b..b74847a 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -476,7 +476,7 @@ static int esp6_err(struct sk_buff *skb, struct
inet6_skb_parm *opt,
if (type == NDISC_REDIRECT)
ip6_redirect(skb, net, skb->dev->ifindex, 0);
else
- ip6_update_pmtu(skb, net, info, 0, 0);
+ ip6_update_pmtu(net, NULL, skb, info, 0, 0);
xfrm_state_put(x);
return 0;
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 0a37ddc..03816f5 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -92,7 +92,7 @@ static void icmpv6_err(struct sk_buff *skb, struct
inet6_skb_parm *opt,
struct net *net = dev_net(skb->dev);
if (type == ICMPV6_PKT_TOOBIG)
- ip6_update_pmtu(skb, net, info, 0, 0);
+ ip6_update_pmtu(net, NULL, skb, info, 0, 0);
else if (type == NDISC_REDIRECT)
ip6_redirect(skb, net, skb->dev->ifindex, 0);
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index d90a11f..fa873ca 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -599,7 +599,7 @@ static int vti6_err(struct sk_buff *skb, struct
inet6_skb_parm *opt,
if (type == NDISC_REDIRECT)
ip6_redirect(skb, net, skb->dev->ifindex, 0);
else
- ip6_update_pmtu(skb, net, info, 0, 0);
+ ip6_update_pmtu(net, NULL, skb, info, 0, 0);
xfrm_state_put(x);
return 0;
diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c
index 1b9316e..c07a5ac 100644
--- a/net/ipv6/ipcomp6.c
+++ b/net/ipv6/ipcomp6.c
@@ -76,7 +76,7 @@ static int ipcomp6_err(struct sk_buff *skb, struct
inet6_skb_parm *opt,
if (type == NDISC_REDIRECT)
ip6_redirect(skb, net, skb->dev->ifindex, 0);
else
- ip6_update_pmtu(skb, net, info, 0, 0);
+ ip6_update_pmtu(net, NULL, skb, info, 0, 0);
xfrm_state_put(x);
return 0;
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ed44663..8f6a5f1 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1346,7 +1346,7 @@ static bool rt6_cache_allowed_for_pmtu(const struct
rt6_info *rt)
(rt->rt6i_flags & RTF_PCPU || rt->rt6i_node);
}
-static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
+static void __ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
const struct ipv6hdr *iph, u32 mtu)
{
struct rt6_info *rt6 = (struct rt6_info *)dst;
@@ -1377,12 +1377,8 @@ static void __ip6_rt_update_pmtu(struct dst_entry *dst,
const struct sock *sk,
nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
if (nrt6) {
rt6_do_update_pmtu(nrt6, mtu);
-
- /* ip6_ins_rt(nrt6) will bump the
- * rt6->rt6i_node->fn_sernum
- * which will fail the next rt6_check() and
- * invalidate the sk->sk_dst_cache.
- */
+ if (sk)
+ ip6_dst_store(sk, &nrt6->dst, daddr, saddr);
ip6_ins_rt(nrt6);
}
}
@@ -1394,8 +1390,8 @@ static void ip6_rt_update_pmtu(struct dst_entry *dst,
struct sock *sk,
__ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
}
-void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
- int oif, u32 mark)
+void ip6_update_pmtu(struct net *net, struct sock *sk,
+ struct sk_buff *skb, __be32 mtu, int oif, u32 mark)
{
const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
struct dst_entry *dst;
@@ -1410,15 +1406,16 @@ void ip6_update_pmtu(struct sk_buff *skb, struct net
*net, __be32 mtu,
dst = ip6_route_output(net, NULL, &fl6);
if (!dst->error)
- __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
+ __ip6_rt_update_pmtu(dst, sk, iph, ntohl(mtu));
dst_release(dst);
}
EXPORT_SYMBOL_GPL(ip6_update_pmtu);
void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
{
- ip6_update_pmtu(skb, sock_net(sk), mtu,
- sk->sk_bound_dev_if, sk->sk_mark);
+ ip6_update_pmtu(sock_net(sk),
+ (sk->sk_state != TCP_ESTABLISHED) ? NULL : sk,
+ skb, mtu, sk->sk_bound_dev_if, sk->sk_mark);
}
EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
--
2.7.0.rc3.207.g0ac5344
