diff options
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index fe193e5..acdc4c9 100644 --- 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); @@ -1504,7 +1506,7 @@ static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) } #ifdef CONFIG_SYN_COOKIES - if (!th->rst && !th->syn && th->ack) + if (!th->syn) sk = cookie_v4_check(sk, skb, &(IPCB(skb)->opt)); #endif return sk; |
