From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: Status of owner-socketlookup
Date: Wed, 27 Apr 2005 16:52:46 +0200
Message-ID: <426FA73E.3090605@trash.net>
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	<426F64C8.1070601@trash.net> <426FA44A.2010008@evtek.fi>
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To: Juha Heljoranta <juha.heljoranta@evtek.fi>
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Juha Heljoranta wrote:
> Ideas how to identify sending process are indeed needed. How about
> adding sender information (pid) into skb?

Well, it seems the whole concept of associating sockets with processes
is flawed, a socket can be owned by any number of processes, and even a
single packet can be created by multiple processes. For outgoing packets
it would be possible to store the pid in the skb and handle the unlikely
case of a packet created by multiple processes somehow, but for incoming
packets we really don't know which process is going to receive a packet
until it calls recvmsg(). This is too late for filtering with netfilter
because multiple references (device, conntrack, ..) need to be dropped
earlier.

Regards
Patrick