lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-Id: <200910111226.44828.elendil@planet.nl>
Date:	Sun, 11 Oct 2009 12:26:43 +0200
From:	Frans Pop <elendil@...net.nl>
To:	Olaf van der Spek <olafvdspek@...il.com>, netdev@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org
Subject: Re: Enable syn cookies by default

This question is better asked on the kernel network development list.
Original mail from Olaf below.

Cheers,
FJP

=================
Hi,

I'm forwarding Debian feature request #520668.

Could syn cookies be enabled by default?

AFAIK syn cookies only get send when the half-open TCP connection
queue is full. So stuff like window scaling should work fine in normal
situations.

Speaking of which:
When the half-open TCP connection queue is full and syn cookies are
enabled, you get a message like "kernel: possible SYN flooding on port
2710. Sending cookies."
However when syn cookies are disabled, you don't get any message (in
kern.log), although connections to your server are timing out.
Could such a message be added?
Maybe with a suggestion to increase the size of that queue or to
enable syn cookies.

Greetings,

Olaf

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=520668
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=520667
https://bugs.launchpad.net/ubuntu/+bug/57091
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ