ipv4: Namespaceify tcp_fastopen knob

Different namespace application might require enable TCP Fast Open
feature independently of the host.

This patch series continues making more of the TCP Fast Open related
sysctl knobs be per net-namespace.

Reported-by: Luca BRUNO <lucab@debian.org>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 6 deletions

diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c
index e3c33220c418..31b08ec38cb8 100644
--- a/net/ipv4/tcp_fastopen.c
+++ b/net/ipv4/tcp_fastopen.c
@@ -9,8 +9,6 @@
 #include <net/inetpeer.h>
 #include <net/tcp.h>
 
-int sysctl_tcp_fastopen __read_mostly = TFO_CLIENT_ENABLE;
-
 struct tcp_fastopen_context __rcu *tcp_fastopen_ctx;
 
 static DEFINE_SPINLOCK(tcp_fastopen_ctx_lock);
@@ -279,21 +277,22 @@ struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb,
                               struct request_sock *req,
                               struct tcp_fastopen_cookie *foc)
 {
-        struct tcp_fastopen_cookie valid_foc = { .len = -1 };
         bool syn_data = TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq + 1;
+        int tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen;
+        struct tcp_fastopen_cookie valid_foc = { .len = -1 };
         struct sock *child;
 
         if (foc->len == 0) /* Client requests a cookie */
                 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENCOOKIEREQD);
 
-        if (!((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) &&
+        if (!((tcp_fastopen & TFO_SERVER_ENABLE) &&
               (syn_data || foc->len >= 0) &&
               tcp_fastopen_queue_check(sk))) {
                 foc->len = -1;
                 return NULL;
         }
 
-        if (syn_data && (sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_REQD))
+        if (syn_data && (tcp_fastopen & TFO_SERVER_COOKIE_NOT_REQD))
                 goto fastopen;
 
         if (foc->len >= 0 &&  /* Client presents or requests a cookie */
@@ -347,7 +346,7 @@ bool tcp_fastopen_cookie_check(struct sock *sk, u16 *mss,
                 return false;
         }
 
-        if (sysctl_tcp_fastopen & TFO_CLIENT_NO_COOKIE) {
+        if (sock_net(sk)->ipv4.sysctl_tcp_fastopen & TFO_CLIENT_NO_COOKIE) {
                 cookie->len = -1;
                 return true;
         }