From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Cox Subject: Re: [RCF] [PATCH] unprivileged mount/umount Date: Fri, 13 May 2005 19:44:23 +0100 Message-ID: <1116009860.1444.497.camel@localhost.localdomain> References: <20050511170700.GC2141@mail.shareable.org> <1115840139.6248.181.camel@localhost> <20050511212810.GD5093@mail.shareable.org> <1115851333.6248.225.camel@localhost> <20050512010215.GB8457@mail.shareable.org> <20050512064514.GA12315@mail.shareable.org> <20050512151631.GA16310@mail.shareable.org> <1115946620.6248.299.camel@localhost> <1115969123.6248.336.camel@localhost> <1115974780.6248.346.camel@localhost> <1116003238.6248.367.camel@localhost> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Miklos Szeredi , jamie@shareable.org, ericvh@gmail.com, 7eggert@gmx.de, linux-fsdevel@vger.kernel.org, Linux Kernel Mailing List , smfrench@austin.rr.com, hch@infradead.org Return-path: Received: from clock-tower.bc.nu ([81.2.110.250]:61898 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S262478AbVEMSrI (ORCPT ); Fri, 13 May 2005 14:47:08 -0400 To: Ram In-Reply-To: <1116003238.6248.367.camel@localhost> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org > Right but this fix disallows fchdir into a directory belonging to > a different namespace. And hence would disallow the ability to > cross mount across namespaces. A helper can still pass file handles for you, you've changed the semantics a little (and I'm not clear if there is a need to) but I don't see it serves any fundamental purpose. Historical experience is that chroot exiting via fchdir is actually useful