From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: Q: check_unsafe_exec() races (Was: [PATCH 2/4] fix setuid
	sometimes doesn't)
Date: Sun, 29 Mar 2009 05:14:12 +0100
Message-ID: <20090329041412.GG28946@ZenIV.linux.org.uk>
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Cc: Hugh Dickins <hugh@veritas.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Joe Malicki <jmalicki@metacarta.com>,
	Michael Itz <mitz@metacarta.com>,
	Kenneth Baker <bakerk@metacarta.com>,
	Chris Wright <chrisw@sous-sol.org>,
	David Howells <dhowells@redhat.com>,
	Alexey Dobriyan <adobriyan@gmail.com>,
	Greg Kroah-Hartman <gregkh@suse.de>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
To: Oleg Nesterov <oleg@redhat.com>
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On Sun, Mar 29, 2009 at 05:10:22AM +0100, Al Viro wrote:

> Frankly, I don't think we really care.  Note that having several sub-threads
> and doing execve() in one of them will kill the rest, so you really want
> to do some kind of synchronization

in userland, that is

> to get something similar to reasonable
> behaviour anyway.