tcp: tcp_syn_flood_action() can be static

After commit 1fb6f159fd21 ("tcp: add tcp_conn_request"),
tcp_syn_flood_action() is no longer used from IPv6.

We can make it static, by moving it above tcp_conn_request()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 29 insertions, 31 deletions

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 42690daa924e..963303fb96ae 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -529,8 +529,6 @@ int tcp_write_wakeup(struct sock *);
 void tcp_send_fin(struct sock *sk);
 void tcp_send_active_reset(struct sock *sk, gfp_t priority);
 int tcp_send_synack(struct sock *);
-bool tcp_syn_flood_action(struct sock *sk, const struct sk_buff *skb,
-                          const char *proto);
 void tcp_push_one(struct sock *, unsigned int mss_now);
 void tcp_send_ack(struct sock *sk);
 void tcp_send_delayed_ack(struct sock *sk);
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 023196f7ec37..18b80e8bc533 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5987,6 +5987,35 @@ struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
 }
 EXPORT_SYMBOL(inet_reqsk_alloc);
 
+/*
+ * Return true if a syncookie should be sent
+ */
+static bool tcp_syn_flood_action(struct sock *sk,
+                                 const struct sk_buff *skb,
+                                 const char *proto)
+{
+        const char *msg = "Dropping request";
+        bool want_cookie = false;
+        struct listen_sock *lopt;
+
+#ifdef CONFIG_SYN_COOKIES
+        if (sysctl_tcp_syncookies) {
+                msg = "Sending cookies";
+                want_cookie = true;
+                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDOCOOKIES);
+        } else
+#endif
+                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDROP);
+
+        lopt = inet_csk(sk)->icsk_accept_queue.listen_opt;
+        if (!lopt->synflood_warned && sysctl_tcp_syncookies != 2) {
+                lopt->synflood_warned = 1;
+                pr_info("%s: Possible SYN flooding on port %d. %s.  Check SNMP counters.\n",
+                        proto, ntohs(tcp_hdr(skb)->dest), msg);
+        }
+        return want_cookie;
+}
+
 int tcp_conn_request(struct request_sock_ops *rsk_ops,
                      const struct tcp_request_sock_ops *af_ops,
                      struct sock *sk, struct sk_buff *skb)
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index e073517b2cc7..5aababa20a21 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -856,35 +856,6 @@ static void tcp_v4_reqsk_destructor(struct request_sock *req)
         kfree(inet_rsk(req)->opt);
 }
 
-/*
- * Return true if a syncookie should be sent
- */
-bool tcp_syn_flood_action(struct sock *sk,
-                         const struct sk_buff *skb,
-                         const char *proto)
-{
-        const char *msg = "Dropping request";
-        bool want_cookie = false;
-        struct listen_sock *lopt;
-
-#ifdef CONFIG_SYN_COOKIES
-        if (sysctl_tcp_syncookies) {
-                msg = "Sending cookies";
-                want_cookie = true;
-                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDOCOOKIES);
-        } else
-#endif
-                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDROP);
-
-        lopt = inet_csk(sk)->icsk_accept_queue.listen_opt;
-        if (!lopt->synflood_warned && sysctl_tcp_syncookies != 2) {
-                lopt->synflood_warned = 1;
-                pr_info("%s: Possible SYN flooding on port %d. %s.  Check SNMP counters.\n",
-                        proto, ntohs(tcp_hdr(skb)->dest), msg);
-        }
-        return want_cookie;
-}
-EXPORT_SYMBOL(tcp_syn_flood_action);
 
 #ifdef CONFIG_TCP_MD5SIG
 /*