Re: Linux not seeing ACK on FIN|ACK packets

Taral (taral@cyberjunkie.com)
Mon, 29 Mar 1999 18:44:44 -0600 (EST)


This message is in MIME format. The first part should be readable text,
while the remaining parts are likely unreadable without MIME-aware tools.
Send mail to mime@docserver.cac.washington.edu for more info.

--8323328-381863815-922754684=:463
Content-Type: TEXT/PLAIN; charset=US-ASCII

On Mon, 29 Mar 1999, Pete Wyckoff wrote:

> Yes, please do repost. If possible, can you add a "how to reproduce"
> formula so I (and others) can play around with it with debugging on in
> the kernel? It could be something that only happens under some odd
> timing conditions between you and your popper, though. Having it show
> up between two boxes of which you have control would be ideal, though
> possibly not going to happen.

Okay. After much agonizing and rebooting (I don't think I've ever rebooted
as much as for kernel debugging, even in <gasp> Windows), I found the
problem. Attached are the patch and the tcpdump which exhibits the faulty
behavior.

Taral

--8323328-381863815-922754684=:463
Content-Type: TEXT/PLAIN; charset=US-ASCII; name="tcp_input.c.fin.patch"
Content-Transfer-Encoding: BASE64
Content-ID: <Pine.LNX.4.10.9903291844440.463@taral.dobiecenter.com>
Content-Description:
Content-Disposition: attachment; filename="tcp_input.c.fin.patch"
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--8323328-381863815-922754684=:463
Content-Type: TEXT/PLAIN; charset=US-ASCII; name="tcp_broken.txt"
Content-Transfer-Encoding: BASE64
Content-ID: <Pine.LNX.4.10.9903291844441.463@taral.dobiecenter.com>
Content-Description:
Content-Disposition: attachment; filename="tcp_broken.txt"
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--8323328-381863815-922754684=:463--

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/