From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Lezcano <dlezcano-NmTC/0ZBporQT0dZR+AlfA@public.gmane.org>
Subject: netns : close all sockets at unshare ?
Date: Tue, 02 Oct 2007 23:45:24 +0200
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To: "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
Cc: Linux Containers <containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org>
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Hi,

I was looking at some cornercases and trying to figure out what happens 
if someone does:

1 - fd = socket(...)
2 - unshare(CLONE_NEWNET)
3 - bind(fd, ...) / listen(fd, ...)

There is here an interaction between two namespaces.
Trying to catch all these little tricky paths everywhere with the 
network namespace is painful, perhaps we should consider a more radical 
solution.

Shall we close all fd sockets when doing an unshare ? like a 
close-on-exec behavior ?