From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030511AbeBNOSN (ORCPT ); Wed, 14 Feb 2018 09:18:13 -0500 Received: from lilium.sigma-star.at ([109.75.188.150]:51704 "EHLO lilium.sigma-star.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030288AbeBNOSM (ORCPT ); Wed, 14 Feb 2018 09:18:12 -0500 From: Richard Weinberger To: Enrico Weigelt Cc: Aleksa Sarai , Linux Containers , "linux-kernel@vger.kernel.org" Subject: Re: plan9 semantics on Linux - mount namespaces Date: Wed, 14 Feb 2018 15:19:24 +0100 Message-ID: <2050418.Dl5pXkWGsk@blindfold> In-Reply-To: References: <0f058286-a432-379b-f559-f2fe713807ab@metux.net> <2658681.ustYaP9yci@blindfold> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Mittwoch, 14. Februar 2018, 15:03:55 CET schrieb Enrico Weigelt: > On 14.02.2018 13:53, Richard Weinberger wrote: > > It does what you ask it for. > Also see the --setgroups switch.> AFAICT > > --setgroups=deny is the new > default, then your command line should just> work. Maybe your unshare > tool is too old. > Also doesn't help: > > daemon@alphabox:~ unshare -U -r --setgroups=deny > unshare: can't open '/proc/self/setgroups': Permission denied Works here(tm). Can you debug it? Maybe we miss something obvious. > >> What I'd like to achieve is that processes can manipulate their private > >> >> namespace at will and mount other filesystems (primarily 9p and > fuse).>>>> For that, I need to get rid of setuid (and per-file caps) for > these>> private namespaces.> > > > This is exactly why we have the user namespace. > > In the user namespace you can create your own mount namespace and do > > (almost) whatever you want. > > What's the exact relation between user and mnt namespace ? > Why do I need an own user ns for private mnt ns ? (except for the suid > bit, which I wanna get rid of anyways). mount related system calls are root-only. Therefore you need the user namespace to become a root in your own little world. :) Thanks, //richard -- sigma star gmbh - Eduard-Bodem-Gasse 6 - 6020 Innsbruck - Austria ATU66964118 - FN 374287y