From: Petar Penkov <ppenkov@google.com>
Date: Mon, 29 Jul 2019 09:59:13 -0700
Subject: tcp: tcp_syn_flood_action read port from socket
Patch-mainline: v5.4-rc1
Git-commit: 965112785e4bd4355262c6c5a32ea8f349adb401
References: bsc#1154353
This allows us to call this function before an SKB has been
allocated.
Signed-off-by: Petar Penkov <ppenkov@google.com>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
net/ipv4/tcp_input.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -6422,9 +6422,7 @@ EXPORT_SYMBOL(inet_reqsk_alloc);
/*
* Return true if a syncookie should be sent
*/
-static bool tcp_syn_flood_action(const struct sock *sk,
- const struct sk_buff *skb,
- const char *proto)
+static bool tcp_syn_flood_action(const struct sock *sk, const char *proto)
{
struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue;
const char *msg = "Dropping request";
@@ -6444,7 +6442,7 @@ static bool tcp_syn_flood_action(const s
net->ipv4.sysctl_tcp_syncookies != 2 &&
xchg(&queue->synflood_warned, 1) == 0)
net_info_ratelimited("%s: Possible SYN flooding on port %d. %s. Check SNMP counters.\n",
- proto, ntohs(tcp_hdr(skb)->dest), msg);
+ proto, sk->sk_num, msg);
return want_cookie;
}
@@ -6487,7 +6485,7 @@ int tcp_conn_request(struct request_sock
*/
if ((net->ipv4.sysctl_tcp_syncookies == 2 ||
inet_csk_reqsk_queue_is_full(sk)) && !isn) {
- want_cookie = tcp_syn_flood_action(sk, skb, rsk_ops->slab_name);
+ want_cookie = tcp_syn_flood_action(sk, rsk_ops->slab_name);
if (!want_cookie)
goto drop;
}