Re: [GIT] Networking

On 2011.09.18 at 21:46 +0200, Eric Dumazet wrote:

Le dimanche 18 septembre 2011 à 21:23 +0200, Markus Trippelsdorf a
écrit :

quoted

On 2011.09.18 at 11:06 -0700, Linus Torvalds wrote:

quoted

2011/9/17 David Miller [off-list ref]:

quoted

dpward (2):
     net: Make flow cache namespace-aware
     net: Handle different key sizes between address families in flow cache

nhorman (1):
     net: don't clear IFF_XMIT_DST_RELEASE in ether_setup

rajan.aggarwal85@gmail.com (1):
     net/can/af_can.c: Change del_timer to del_timer_sync

Guys, if somebody has such a broken email setup that they don't even
show their own name, don't take patches from them.

If you cannot even set up email sanely, there is zero reason to
believe that the patch should be good. And if the patch is trivial and
you want to take it despite the source of the patch being crap, please
spend the five seconds to fix it up.

Proper names are part of the commit message. Don't make it look like
crap. I get ugly flashbacks to SVN or CVS when I see stuff like this.
Don't do it.

Plus commit 946cedccbd73874 breaks the build:

  LD      init/built-in.o
  LD      .tmp_vmlinux1
net/built-in.o:sysctl_net.c:function tcp_v4_conn_request: error: undefined reference to 'cookie_v4_init_sequence'
make: *** [.tmp_vmlinux1] Error 1

commit 946cedccbd7387488d2cee5da92cdfeb28d2e670
Author: Eric Dumazet [off-list ref]
Date:   Tue Aug 30 03:21:44 2011 +0000

    tcp: Change possible SYN flooding messages

    "Possible SYN flooding on port xxxx " messages can fill logs on servers.

    Change logic to log the message only once per listener, and add two new
    SNMP counters to track :

    TCPReqQFullDoCookies : number of times a SYNCOOKIE was replied to client

    TCPReqQFullDrop : number of times a SYN request was dropped because
    syncookies were not enabled.

    Based on a prior patch from Tom Herbert, and suggestions from David.

Oh well, trying to remove those ugly #ifdef was not so easy.
I'll cook a patch, thanks for the report

The following works for me:

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index c34f015..ef9dd55 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c

@@ -1264,7 +1264,9 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 	 * evidently real one.
 	 */
 	if (inet_csk_reqsk_queue_is_full(sk) && !isn) {
+#ifdef CONFIG_SYN_COOKIES
 		want_cookie = tcp_syn_flood_action(sk, skb, "TCP");
+#endif
 		if (!want_cookie)
 			goto drop;
 	}

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 3c9fa61..7ffc3b1 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c

@@ -1174,7 +1174,9 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 		goto drop;
 
 	if (inet_csk_reqsk_queue_is_full(sk) && !isn) {
+#ifdef CONFIG_SYN_COOKIES
 		want_cookie = tcp_syn_flood_action(sk, skb, "TCPv6");
+#endif
 		if (!want_cookie)
 			goto drop;
 	}

-- 
Markus