From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <cl-vYTEC60ixJUAvxtiuMwx3w@public.gmane.org>
Subject: Re: [RFC] capabilities: Ambient capabilities
Date: Mon, 30 Mar 2015 10:05:58 -0500 (CDT)
Message-ID: <alpine.DEB.2.11.1503301003460.6781@gentwo.org>
References: <933931146caf5dac58379f50c017bff9f6c47661.1426183417.git.luto@kernel.org> <CAGXu5jKfvswdUMcrGbr6+wn1ME_JkySMvdNd0wvvHpbQ1C7HUg@mail.gmail.com> <CALQRfL7b8CjYgUnVy3jykNwv48fOc03T385RKo--cfv25YenBg@mail.gmail.com>
 <CAObL_7HgU-ekb7mJS7C=0=idfrzV6=CSqTrG2LvUgdDtvbJx_w@mail.gmail.com> <CALQRfL6HUGMfPtsqLcSed8G14Yqg27R8tpDnMZOKtvQE+rqX0A@mail.gmail.com> <CALCETrVz39pJmMAEFodBNA8cOZjd0xkH95EzMazY0MWJDtpYgg@mail.gmail.com> <CALQRfL5FGGUnK7+Ss=MSDGmxpAERTUjezardGnH3QouBwhbZ4A@mail.gmail.com>
 <CALCETrUGASa3Gp6cC1zdAahcS59DOdyLnTtgNX7t7FucMZLmoQ@mail.gmail.com> <CALQRfL6z2dEtPkWiuGydT0a+y4iWm2qw-cY0Rk9hA-K4gPw_qA@mail.gmail.com> <CALCETrWRHRVLotFs=Cpdr=7KjE7q52NdT62GxZg=xjv+LFZBqw@mail.gmail.com> <CALQRfL7AyadFcu9JqtC6FGnuuqY7zbnFAL81XnwBvn0o6c6UWQ@mail.gmail.com>
 <alpine.DEB.2.11.1503300754070.5031@gentwo.org> <CALCETrW9ckw=7-1JSyFkenhFu2_1MvVqjA+inOmsuuWemGaU0w@mail.gmail.com>
Content-Type: TEXT/PLAIN; charset=US-ASCII
Return-path: <linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
In-Reply-To: <CALCETrW9ckw=7-1JSyFkenhFu2_1MvVqjA+inOmsuuWemGaU0w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
To: Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>, Andrew Lutomirski <luto-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Ted Ts'o <tytso-3s7WtUTddSA@public.gmane.org>, Andrew Morton <akpm-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>, "Andrew G. Morgan" <morgan-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Linux API <linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Mimi Zohar <zohar-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>, Michael Kerrisk <mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Austin S Hemmelgarn <ahferroin7-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, linux-security-module <linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Aaron Jones <aaronmdjones-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Serge Hallyn <serge.hallyn-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>, LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Markku Savela <msa-kXoF896ld44xHbG02/KK1g@public.gmane.org>, Kees Cook <keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>, Jonathan Corbet <corbet-T1hC0tSOHrs@public.gmane.org>
List-Id: linux-api@vger.kernel.org

On Mon, 30 Mar 2015, Andy Lutomirski wrote:

> > Would this suffice? It puts the CAP_SETPCAP limitation back to how it
> > was in my earlier patch.
> I really don't like that variant.  CAP_SETPCAP is dangerous and so
> absurdly powerful that people really shouldn't hand it out.

According to

	man 7 capabilities

CAP_SETPCAP is required to setup securebits.

This hides the functionality behind yet another stage of security and
obscures this ability somewhat more?