syncookies: make v4/v6 synflood warning behaviour the same

both syn_flood_warning functions print a message, but
ipv4 version only prints a warning if CONFIG_SYN_COOKIES=y.

Make the v4 one behave like the v6 one.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 202cf09..a13f881 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -793,19 +793,20 @@ static void tcp_v4_reqsk_destructor(struct request_sock *req)
        kfree(inet_rsk(req)->opt);
 }
 
-#ifdef CONFIG_SYN_COOKIES
-static void syn_flood_warning(struct sk_buff *skb)
+static void syn_flood_warning(const struct sk_buff *skb)
 {
-       static unsigned long warntime;
+       const char *msg;
 
-       if (time_after(jiffies, (warntime + HZ * 60))) {
-               warntime = jiffies;
-               printk(KERN_INFO
-                      "possible SYN flooding on port %d. Sending cookies.\n",
-                      ntohs(tcp_hdr(skb)->dest));
-       }
-}
+#ifdef CONFIG_SYN_COOKIES
+       if (sysctl_tcp_syncookies)
+               msg = "Sending cookies";
+       else
 #endif
+               msg = "Dropping request";
+
+       pr_info("TCP: Possible SYN flooding on port %d. %s.\n",
+                               ntohs(tcp_hdr(skb)->dest), msg);
+}
 
 /*
  * Save and compile IPv4 options into the request_sock if needed.
@@ -1243,6 +1244,8 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
         * evidently real one.
         */
        if (inet_csk_reqsk_queue_is_full(sk) && !isn) {
+               if (net_ratelimit())
+                       syn_flood_warning(skb);
 #ifdef CONFIG_SYN_COOKIES
                if (sysctl_tcp_syncookies) {
                        want_cookie = 1;
@@ -1328,7 +1331,6 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 
        if (want_cookie) {
 #ifdef CONFIG_SYN_COOKIES
-               syn_flood_warning(skb);
                req->cookie_ts = tmp_opt.tstamp_ok;
 #endif
                isn = cookie_v4_init_sequence(sk, skb, &req->mss);