Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755299Ab3JJL5U (ORCPT ); Thu, 10 Oct 2013 07:57:20 -0400 Received: from mail-qa0-f54.google.com ([209.85.216.54]:34849 "EHLO mail-qa0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754221Ab3JJL5Q (ORCPT ); Thu, 10 Oct 2013 07:57:16 -0400 MIME-Version: 1.0 X-Originating-IP: [86.59.245.170] In-Reply-To: <87vc15mjuw.fsf@xmission.com> References: <8761v7h2pt.fsf@tw-ebiederman.twitter.com> <87li281wx6.fsf_-_@xmission.com> <87a9ioo37a.fsf_-_@xmission.com> <20131007043919.GB10284@mail.hallyn.com> <87vc191sf2.fsf@xmission.com> <87d2ngyb02.fsf@xmission.com> <20131008160601.GJ14242@tucsk.piliscsaba.szeredi.hu> <20131008161135.GK14242@tucsk.piliscsaba.szeredi.hu> <87li23trll.fsf@tw-ebiederman.twitter.com> <87vc15mjuw.fsf@xmission.com> Date: Thu, 10 Oct 2013 13:57:15 +0200 Message-ID: Subject: Re: [RFC][PATCH 4/3] vfs: Allow rmdir to remove mounts in all but the current mount namespace From: Miklos Szeredi To: "Eric W. Biederman" Cc: Andy Lutomirski , "Serge E. Hallyn" , Al Viro , Linux-Fsdevel , Kernel Mailing List , Rob Landley , Linus Torvalds Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1187 Lines: 32 On Thu, Oct 10, 2013 at 1:43 PM, Eric W. Biederman wrote: > I have been weighing the pros and the cons of this. > > At this point the most practical path I can see is to block unlink, > rename, and rmdir if there is a mount in the local namespace. > > At the very least that makes very limited additions to what applications > can depend on from the vfs, and even more importantly that can be ready > by 3.13. > > Furthermore it removes the nasty need for filesystems to lie to the vfs, > and removes the nasty DOS that non-local mountpoints are. Agreed 100%. > Miklos if you as the fuse maintainer aren't worried about network > filesystems, and multiple namespaces I won't worry either. Especially > since modern versions of fuse aren't affected. I think the above conditions (local mount blocks unlink/rename) are enough to prevent most of the problems, of which there aren't many in any case. Thanks, Miklos -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/