linux-kernel - Re: Window scaling problem?

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] [thread-next>] [day] [month] [year] [list]

Date:	Sun, 10 Dec 2006 15:21:51 -0500 (EST)
From:	Cal Peake <cp@...olutedigital.net>
To:	Jan Engelhardt <jengelh@...ux01.gwdg.de>
cc:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: Window scaling problem?

On Sun, 10 Dec 2006, Jan Engelhardt wrote:

> for some reason unknown to me, some TCP connections just hang or get
> reset after some kilobytes have been transferred. I suppose it is a
> router with broken window scaling, but I can not say for sure from
> the tcpdump logs.

I observed the exact same behavior on a client's network not too long ago 
which used a Cyberguard firewall as a NAT gateway. I didn't have time to 
fully look into it but disabling TCP window scaling in Linux allowed me to 
work without problems.

> If anyone could take a look, I'd be grateful. Kernel currently
> running is 2.6.18.5, but I have seen this with 2.6.17 I was running
> two months ago too, so I do not suspect a kernel bug.

I saw this with kernels v2.6.16, v2.6.17, and v2.6.18. Windows XP however 
didn't seem to have any problems. So unless Windows doesn't have window 
scaling on by default (or uses a workaround) it could be a broken kernel.

Wish I could be more help...

  - C.

-- 
"There is nothing wrong with your television set. Do not attempt
    to adjust the picture. We are controlling transmission."
                    -- The Outer Limits

-
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/