From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: [PATCH] peer_pid checking in ip_queue
Date: Wed, 24 Mar 2004 01:47:47 +0100
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Cc: Pablo Neira <pablo@eurodev.net>,  netfilter-devel@lists.netfilter.org,
 Harald Welte <laforge@netfilter.org>
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To: Henrik Nordstrom <hno@marasystems.com>
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Henrik Nordstrom wrote:
> On Tue, 23 Mar 2004, Patrick McHardy wrote:
> 
> 
>>It can happen if peer_pid is checked outside the locked section on one
>>CPU and changed on another at the same time. I don't consider it
>>important, as the exact point in time at which the first packet will be
>>received is non-deterministic for userspace anyway.
> 
> 
> What about when the user program closes? How bad it is to have read the 
> pid and then there is no userspace there?

It's no problem, netlink_unicast checks for existance of the socket,
which will be gone with the reader. If no socket is found it returns
-ECONNREFUSED.

Regards
Patrick


> 
> Regards
> Henrik
>