From mboxrd@z Thu Jan  1 00:00:00 1970
From: Henrik Nordstrom <hno@marasystems.com>
Subject: Re: Problem with sk_buff
Date: Fri, 7 Jun 2002 21:09:39 +0200
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To: "Damiano Bolzoni" <damiano.bolzoni@tin.it>,
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Damiano Bolzoni wrote:
> Hi people,
> I wrote a kernel module that uses netfilter. I'm interested on incoming IP
> packets that carry a TCP segment with SYN flag active. What I want to do is
> to know which socket has been created in order to handle that connection
> and I want to close it. sk_buff holds two pointer: struct sock* and struct
> socket* but they point to NULL.
> At this time I can test if the TCP segment has the SYN flag set but I can't
> close the socket...
> Anyone can help me?

This is too early in the packet processing path. The socket is not yet known. 
These fields is only valid on locally generated packets (outgoing/sent 
packets).

You will need to make a call into the TCP/IP kernel to look up the local 
socket.

Regards
Henrik