tcp: make sysctl_tcp_ecn namespace aware

As per suggestion from Eric Dumazet this patch makes tcp_ecn sysctl
namespace aware.  The reason behind this patch is to ease the testing
of ecn problems on the internet and allows applications to tune their
own use of ecn.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 3 deletions

diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index b236ef04914f..ef54377fb11c 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -232,7 +232,8 @@ static inline struct sock *get_cookie_sock(struct sock *sk, struct sk_buff *skb,
  *
  * return false if we decode an option that should not be.
  */
-bool cookie_check_timestamp(struct tcp_options_received *tcp_opt, bool *ecn_ok)
+bool cookie_check_timestamp(struct tcp_options_received *tcp_opt,
+                        struct net *net, bool *ecn_ok)
 {
         /* echoed timestamp, lowest bits contain options */
         u32 options = tcp_opt->rcv_tsecr & TSMASK;
@@ -247,7 +248,7 @@ bool cookie_check_timestamp(struct tcp_options_received *tcp_opt, bool *ecn_ok)
 
         tcp_opt->sack_ok = (options & (1 << 4)) ? TCP_SACK_SEEN : 0;
         *ecn_ok = (options >> 5) & 1;
-        if (*ecn_ok && !sysctl_tcp_ecn)
+        if (*ecn_ok && !net->ipv4.sysctl_tcp_ecn)
                 return false;
 
         if (tcp_opt->sack_ok && !sysctl_tcp_sack)
@@ -295,7 +296,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
         memset(&tcp_opt, 0, sizeof(tcp_opt));
         tcp_parse_options(skb, &tcp_opt, &hash_location, 0, NULL);
 
-        if (!cookie_check_timestamp(&tcp_opt, &ecn_ok))
+        if (!cookie_check_timestamp(&tcp_opt, sock_net(sk), &ecn_ok))
                 goto out;
 
         ret = NULL;