From: Olaf Kirch <okir@suse.de>
Subject: xprt_bindresvport
Date: Wed, 8 Dec 2004 09:58:48 +0100
Message-ID: <20041208085848.GB12215@suse.de>
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To: nfs@lists.sourceforge.net
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Hi,

the current xprt_bindresvport implementation will search for a privileged
port by counting down from 800 to 0. I think this is a bug, because it
will potentially interfere with services trying to bind to low ports as
well. The bindresvport implementation in glibc picks from the 600-1023
range.

I also think it would be good to start at a "random" port. Otherwise,
when you reboot, the server may still have a TCB for the old connection
and send you an ACK probe when you try to connect (if all goes well), and
the client's TCP stack will RST and fail the connect. If things go
not-so-well you have a packet filter somewhere inbetween that eats the
ACK probe because its connection tracking engine thinks the connection
is in half-open and shouldn't see any SYN-less ACKs yet.

Olaf
-- 
Olaf Kirch     | Things that make Monday morning interesting, #2:
okir@suse.de   |        "We have 8,000 NFS mount points, why do we keep
---------------+ 	 running out of privileged ports?"


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