Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751497AbcCHWl0 (ORCPT ); Tue, 8 Mar 2016 17:41:26 -0500 Received: from h2.hallyn.com ([78.46.35.8]:49342 "EHLO h2.hallyn.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751246AbcCHWlT (ORCPT ); Tue, 8 Mar 2016 17:41:19 -0500 Date: Tue, 8 Mar 2016 16:41:16 -0600 From: "Serge E. Hallyn" To: Andy Lutomirski Cc: Serge Hallyn , Kees Cook , Colin Walters , Linux Containers , "linux-kernel@vger.kernel.org" , Seth Forshee , "Eric W. Biederman" , Stephane Graber Subject: Re: Thoughts on tightening up user namespace creation Message-ID: <20160308224116.GA17693@mail.hallyn.com> References: <20160308060657.GA3565@mail.hallyn.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1032 Lines: 23 Quoting Andy Lutomirski (luto@amacapital.net): > On Mar 7, 2016 10:06 PM, "Serge E. Hallyn" wrote: > > > > On Mon, Mar 07, 2016 at 09:15:25PM -0800, Andy Lutomirski wrote: > > > - Ubuntu requires CAP_SYS_ADMIN > > > > No, it does not. It has temporarily re-added a sysctl which can enable > > that behavior, but it's not set by default. The reason for providing it > > is not a distrust of user namespaces in general, but because we're enabling > > some bleeding edge patches which haven't been accepted upstream yet. Once > > they're accepted upstream I expect that patch to be dropped again, unless > > it has gone upstream. > > > > Debian does afaik still have a version of a patch I'd originally written > > before user namespaces were upstream which defaulted unprivileged userns > > cloning to off. Did you mean Debian here? > > I meant Ubuntu 14.04, which I tested, possibly poorly. Weird, 14.04 with the default kernel (3.13.0-79-generic #123-Ubuntu) doesn't have the sysctl at all. -serge