tg3 in 2.6.12-rc6 and Cisco PIX SMTP fixup

From: Lars Roland
Date: Thu Jun 16 2005 - 07:46:43 EST


I am testing kernel 2.6.12-rc6 on a 6 IBM 335 servers. The NICs are
gigabit broadcom. If I use the tg3 driver then each of the servers are
unable to communicate with a Cisco PIX using SMTP fixup, the
connection simply get cut:

telnet xx.x.xx.xx 25
Connected to
Escape character is '^]'.
mail to: <test@xxxxxxxx>
Connection closed by foreign host.

Using tcpdump does not give me any clue as to what goes wrong, the
connection is simply lost so I am suspecting some kind of TX/RX mess
up. If I instead use the tg3 driver in kernel (or the official
broadcom bcm5700 driver (version 8.1.55) with kernel 2.6.12-rc6) then
I get:

telnet 25
Connected to
Escape character is '^]'.
220 ***************
mail to: <test@xxxxxxxx>
250 ok
Connection closed by foreign host.

So are there any differences in the tg3 driver between and
2.6.12-rc6 that would cause this kind of behaviour ?.

I know that SMTP fixup is mostly a poorly implemented Sendmail
security fix left over from the pre ESMTP era that cripples SMTP
connectivity without offering any real
security advantages. So the best thing would be to turn it off, but
given that I do not control the firewall and the admin refuses to
change it because he believes it to be a security risk then I am
looking for another solution (still hoping that it is not shifting
NICs in all my servers).


Lars Roland
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