From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DE04DC004D2 for ; Sun, 30 Sep 2018 23:47:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96615206B7 for ; Sun, 30 Sep 2018 23:47:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 96615206B7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=vivier.eu Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726741AbeJAGWI (ORCPT ); Mon, 1 Oct 2018 02:22:08 -0400 Received: from mout.kundenserver.de ([212.227.126.133]:51561 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726454AbeJAGWI (ORCPT ); Mon, 1 Oct 2018 02:22:08 -0400 Received: from localhost.localdomain ([78.238.229.36]) by mrelayeu.kundenserver.de (mreue012 [212.227.15.167]) with ESMTPSA (Nemesis) id 1Mpkwn-1fNWi32jCn-00qDNg; Mon, 01 Oct 2018 01:46:38 +0200 Received: from localhost.localdomain ([78.238.229.36]) by mrelayeu.kundenserver.de (mreue012 [212.227.15.167]) with ESMTPSA (Nemesis) id 1Mpkwn-1fNWi32jCn-00qDNg; Mon, 01 Oct 2018 01:46:38 +0200 From: Laurent Vivier To: linux-kernel@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, James Bottomley , Alexander Viro , linux-api@vger.kernel.org, Eric Biederman , Dmitry Safonov , Andrei Vagin , containers@lists.linux-foundation.org, Laurent Vivier Subject: [RFC 0/2] ns: introduce binfmt_misc namespace Date: Mon, 1 Oct 2018 01:46:26 +0200 Message-Id: <20180930234628.25528-1-laurent@vivier.eu> X-Mailer: git-send-email 2.17.1 X-Provags-ID: V03:K1:h7ZxYlqTEwGJYfdXMNCiuyjy6YAGhrPsSxrUXkxn8T/t6ILN6LP s7gnsvWoHJSdzPezoVqUsffhxxMmD+wdeVWzCCsfpQUN3TAtFAt6WPHE4f5lH52K379PW/f P1cgFn86GCFODxGORI3ABnBh+LmwOK9zSvXAFOtTJO3T3hP2bTTer7uF48izV5oxXb2tELX GKyZBpG6ZjWUuxSVh9nxg== X-UI-Out-Filterresults: notjunk:1;V01:K0:isBErN8T5yc=:rtKtPzKW41OU46auNEcNaQ ZpG97vCA0KiXOtAeB4mtycVKJbZ1vKP5wtGrm+iyDXJLUIJqYsprFAq6YhKqnv/9HeLe7v4du jrNfZzNsB1HqlWJk3EjVz9tUE93PVKyb/zP/yq4jV6l+HdH5nSqz2KlfTlv3j1D+PwZPUevdN 47PvvGsWeQJKdgxG56wI1uMQPSAsC9HFJeW7OIWZ3sHHKKRrsirRLAWHRHlQbKACQbbvtmBjo 55y9wyb0VVltPPE5i5IAxDgIFPVAgsLteGDCwMyfEAH03ddM75ZyDwdvHakdFZPEGLPCgNWl9 fUrhIWd9sGK5gEHDUrVcWqGSUlzWs/7GlHolY4/tPALE4oFeRLAPtN9eJ9+5BUvd99cR+wTat TnSNbHGWQpZxMxutzNX5boD1e0DcnRkCv9KMf1DcxLe8T1A2Mb4+dppdKuw0Ks+OdGpgglegR unjNjyGwVtOcNKOYgoVDnqJ9/uc7cMij8Z3pzh4U/bLYIRamf0pX79DxKqQb0qi6/ZY13TYCt 2coMagvTuuO9Pa4wmbiAbj1CPpzHw11siUBKZFhRkahhus4h9OXQP3iGBp4uSYhzh8FnmBQ74 b1YKDzmqaSCmwZQy51qGCvuZelB97axzgIGt9r9r4ZcXWV6hLexiazheonf7fP7p1FdLQ/N3y nEBGx6mFYHmxJl3fg/bQvsZ3tFw2NZKqV5NOhZlgB4nu9AOBNZh7yn71I8adA5BB3tao= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This series introduces a new namespace for binfmt_misc. This allows to define a new interpreter for each new container. But the main goal is to be able to chroot to a directory using a binfmt_misc interpreter without being root. I have a modified version of unshare at: git@github.com:vivier/util-linux.git branch unshare-chroot with some new options to unshare binfmt_misc namespace and to chroot to a directory. If you have a directory /chroot/powerpc/jessie containing debian for powerpc binaries and a qemu-ppc interpreter, you can do for instance: $ uname -a Linux fedora28-wor-2 4.19.0-rc5+ #18 SMP Mon Oct 1 00:32:34 CEST 2018 x86_64 x86_64 x86_64 GNU/Linux $ ./unshare --map-root-user --fork --pid \ --load-binfmt ":qemu-ppc:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x14:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/qemu-ppc:OC" \ --root=/chroot/powerpc/jessie /bin/bash -l Linux fedora28-wor-2 4.19.0-rc5+ #18 SMP Mon Oct 1 00:32:34 CEST 2018 ppc GNU/Linux uid=0(root) gid=0(root) groups=0(root),65534(nogroup) total 5940 drwxr-xr-x. 2 nobody nogroup 4096 Aug 12 00:58 bin drwxr-xr-x. 2 nobody nogroup 4096 Jun 17 20:26 boot drwxr-xr-x. 4 nobody nogroup 4096 Aug 12 00:08 dev drwxr-xr-x. 42 nobody nogroup 4096 Sep 28 07:25 etc drwxr-xr-x. 3 nobody nogroup 4096 Sep 28 07:25 home drwxr-xr-x. 9 nobody nogroup 4096 Aug 12 00:58 lib drwxr-xr-x. 2 nobody nogroup 4096 Aug 12 00:08 media drwxr-xr-x. 2 nobody nogroup 4096 Aug 12 00:08 mnt drwxr-xr-x. 3 nobody nogroup 4096 Aug 12 13:09 opt dr-xr-xr-x. 143 nobody nogroup 0 Sep 30 23:02 proc -rwxr-xr-x. 1 nobody nogroup 6009712 Sep 28 07:22 qemu-ppc drwx------. 3 nobody nogroup 4096 Aug 12 12:54 root drwxr-xr-x. 3 nobody nogroup 4096 Aug 12 00:08 run drwxr-xr-x. 2 nobody nogroup 4096 Aug 12 00:58 sbin drwxr-xr-x. 2 nobody nogroup 4096 Aug 12 00:08 srv drwxr-xr-x. 2 nobody nogroup 4096 Apr 6 2015 sys drwxrwxrwt. 2 nobody nogroup 4096 Sep 28 10:31 tmp drwxr-xr-x. 10 nobody nogroup 4096 Aug 12 00:08 usr drwxr-xr-x. 11 nobody nogroup 4096 Aug 12 00:08 var If you want to use the qemu binary provided by your distro, you can use --load-binfmt ":qemu-ppc:M::\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x14:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/bin/qemu-ppc-static:OCF" With the 'F' flag, qemu-ppc-static will be then loaded from the main root filesystem before switching to the chroot. Laurent Vivier (2): ns: introduce binfmt_misc namespace binfmt_misc: move data to binfmt_namespace fs/binfmt_misc.c | 50 +++++----- fs/proc/namespaces.c | 3 + include/linux/binfmt_namespace.h | 63 ++++++++++++ include/linux/nsproxy.h | 2 + include/linux/proc_ns.h | 2 + include/linux/user_namespace.h | 1 + include/uapi/linux/sched.h | 1 + init/Kconfig | 8 ++ kernel/Makefile | 1 + kernel/binfmt_namespace.c | 164 +++++++++++++++++++++++++++++++ kernel/fork.c | 3 +- kernel/nsproxy.c | 18 +++- 12 files changed, 289 insertions(+), 27 deletions(-) create mode 100644 include/linux/binfmt_namespace.h create mode 100644 kernel/binfmt_namespace.c -- 2.17.1