From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Weimer <fweimer@bfk.de>
Subject: Re: e1000 driver and samba
Date: Tue, 18 Sep 2007 15:39:59 +0200
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Cc: Bill Fink <billfink@mindspring.com>,
	"Brandeburg, Jesse" <jesse.brandeburg@intel.com>,
	"L F" <lfabio.linux@gmail.com>,
	"Kok, Auke-jan H" <auke-jan.h.kok@intel.com>,
	"James Chapman" <jchapman@katalix.com>, <netdev@vger.kernel.org>
To: Urs Thuermann <urs@isnogud.escape.de>
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* Urs Thuermann:

> How can a corrupted frame pass the TCP checksum check?

The TCP/IP checksums are extremely weak.  If the corruption is due to
defective SRAM or something like that, it's likely that it causes an
error pattern which is 16-bit-aligned.  And an even number of
16-bit-aligned bit flips is not detected by the TCP checksum. 8-(

Actually, nobody should use TCP without application-level checksums
for that reason.  But of course, there is HTTP.

--=20
=46lorian Weimer                <fweimer@bfk.de>
BFK edv-consulting GmbH       http://www.bfk.de/
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