Stupid filters, and valid Linux kernel driver symbols...

Stupid filters, and valid Linux kernel driver symbols...

[Matti Aarnio]

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  The attached text is an extract from an error report about several
subscribers, as those people ISPs/corporations run rather simple-minded
message content filters.

  No doubt you have received your share of triple alphabet denoted
messages about "services" some purvouers want to draw your attention
into.  Unfortunately (for the Adaptec driver config symbol name)
the  AIC7NNN (lets use "wrong" character here to avoid scanners)
is considered by weak quality scanners to be the very same as "NNN",
which usually is a signature feature in such messages.

To understand this, you need to consider how you would detect when the
"NNN" is stand-alone, and when it is just part of some other string.
See  "man perlre"  for "\w" and "\W" patterns.

Similar kind of content scanner pattern mistakes creep up weekly,
if not daily.  Sometimes forbidden words lie inside other longer
words, sometimes I can't figure out why systems complain about some
messages.


Some people have asked us (me and DaveM) of why we don't run fully
automatic list management (instead of ancient Majordomo 1.x), e.g.
a bounce leads into immediate unsubscription.  Think about that..

/Matti Aarnio

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FAILED:
  Diagnostic texts:
      <<- MAIL From:<linux-kernel-owner@vger.kernel.org>
     ->> 250 Command MAIL OK
     <<- RCPT To:<andreashappe@subdimension.com> NOTIFY=FAILURE ORCPT=rfc822;andreashappe@subdimension.com
     ->> 250 Command RCPT User found OK
     <<- DATA
     ->> 354 Command DATA Start mail input; end with <CRLF>.<CRLF>
     <<- .
     ->> 570 MFilter (line 20: content exception)
FAILED:
  Diagnostic texts:
      <<- MAIL From:<linux-kernel-owner@vger.kernel.org> BODY=8BITMIME SIZE=2153
     ->> 250 2.1.0 <linux-kernel-owner@vger.kernel.org>... Sender ok
     <<- RCPT To:<evan@theunixman.com> NOTIFY=FAILURE ORCPT=rfc822;evan@theunixman.com
     ->> 250 2.1.5 <evan@theunixman.com>... Recipient ok
     <<- DATA
     ->> 354 Enter mail, end with "." on a line by itself
     <<- .
     ->> 550 5.7.1 Go away spammer
FAILED:
  Diagnostic texts:
      <<- MAIL From:<linux-kernel-owner@vger.kernel.org> BODY=8BITMIME SIZE=2153
     ->> 250 2.0.0 linux-kernel-owner@vger.kernel.org OK
     <<- RCPT To:<adderd@wmol.com> NOTIFY=FAILURE ORCPT=rfc822;adderd@wmol.com
     ->> 250 2.0.0 adderd@wmol.com OK
     <<- DATA
     ->> 354 Ready for data
     <<- .
     ->> 554 Filtered out by Filter 0 because "Subject" = "Re: AIC7XXX 6.2.5 driver"

Following is copy of the message headers. Original message content may
be in subsequent parts of this MESSAGE/DELIVERY-STATUS structure.

Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id <S292384AbSBUN7j>; Thu, 21 Feb 2002 08:59:39 -0500
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	id 16dtkE-0003ru-00; Thu, 21 Feb 2002 14:58:46 +0100
Date:	Thu, 21 Feb 2002 14:58:46 +0100
From:	Jens Axboe <axboe@suse.de>
To:	Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc:	Carlo Scarfoglio <scarfoglio@arpacoop.it>,
	linux-kernel@vger.kernel.org, "Justin T. Gibbs" <gibbs@scsiguy.com>
Subject: Re: AIC7XXX 6.2.5 driver
Message-ID: <20020221135846.GA14634@suse.de>
References: <20020221075253.GH2654@suse.de> <E16dtmv-0006z2-00@the-village.bc.nu>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <E16dtmv-0006z2-00@the-village.bc.nu>
Sender:	linux-kernel-owner@vger.kernel.org
Precedence: bulk
X-Mailing-List:	linux-kernel@vger.kernel.org

Re: XXX in AIC7XXX (Let them filter this)

[Richard B. Johnson]

On Thu, 21 Feb 2002, Matti Aarnio wrote:

>   The attached text is an extract from an error report about several
> subscribers, as those people ISPs/corporations run rather simple-minded
> message content filters.
> 
>   No doubt you have received your share of triple alphabet denoted
> messages about "services" some purvouers want to draw your attention
> into.  Unfortunately (for the Adaptec driver config symbol name)
> the  AIC7NNN (lets use "wrong" character here to avoid scanners)
> is considered by weak quality scanners to be the very same as "NNN",
> which usually is a signature feature in such messages.

This is exSEXUALy why EXPLICIT POROGRAPHIC filters can't work.

Cheers,
Dick Johnson

Penguin : Linux version 2.4.1 on an i686 machine (797.90 BogoMips).
Grep-bait: plutonium Cuba President assassination killed Iran Honduras 
nitrate tritium toluene ammonium subway 747 pits iodine critical nuclear
congress attack CIA 9/11 WTC 767