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Date: Thu, 29 Mar 2012 01:37:36 +0400
From: Cyrill Gorcunov <gorcunov@openvz.org>
To: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Oleg Nesterov <oleg@redhat.com>, "Serge E. Hallyn" <serge@hallyn.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Pavel Emelyanov <xemul@parallels.com>
Subject: Re: [rfc] fcntl: Add F_GETOWNER_UIDS option
Message-ID: <20120328213736.GM2204@moon>
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On Wed, Mar 28, 2012 at 04:30:44PM -0500, Serge Hallyn wrote:
> Quoting Oleg Nesterov (oleg@redhat.com):
> > On 03/28, Serge E. Hallyn wrote:
> > >
> > > If you want to
> > > just add the struct cred to the f_owner and do proper uid conversion,
> > > I'll support that too.  (Just grab a ref to the cred in
> > > fs/fcntl.c:f_modown(), and drop the ref in fs/file_table.c:__fput() ).
> > 
> > In this case f_owner.*uid should go away, I guess.
> 
> Yup.
> 
> Which I guess is all the more reason *not* to do this unless we end up
> not going with Eric's userns mapping patchset (which is unlikely).
> 
> > And sigio_perm()
> > should be unified with kill_ok_by_cred() somehow (modulo
> > security_file_send_sigiotask).
> > 
> > Right?
> 
> Maybe, but other differences include current being the signal sender in
> one and recipient in the other, and CAP_KILL being relevent in only
> one.

Hi Serge, thanks a lot for comments! Replying to prev email --
I've skipped cred part intentionally, I guess we need to wait
until Eric's patches hit LKML (if I understand all right) then
I'll expand the patch. I'll think a bit more tomorrow, ok?

	Cyrill