From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 27 Aug 2002 03:50:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 27 Aug 2002 03:50:10 -0400 Received: from tapu.f00f.org ([66.60.186.129]:25515 "EHLO tapu.f00f.org") by vger.kernel.org with ESMTP id ; Tue, 27 Aug 2002 03:50:09 -0400 Date: Tue, 27 Aug 2002 00:54:26 -0700 From: Chris Wedgwood To: Alan Cox Cc: Thunder from the hill , Zheng Jian-Ming , linux-kernel@vger.kernel.org Subject: Re: problems with changing UID/GID Message-ID: <20020827075426.GA6696@tapu.f00f.org> References: <1030382219.1751.14.camel@irongate.swansea.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1030382219.1751.14.camel@irongate.swansea.linux.org.uk> User-Agent: Mutt/1.4i X-No-Archive: Yes Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 26, 2002 at 06:16:59PM +0100, Alan Cox wrote: It changes the whole semantics of every security test in Linux, and breaks most of them totally. Our syscalls know the uid is constant during the call Could we not (eventually) have CLONE_CREDs and then lock using task->cred->lock or whatever? Or might there be cases where this will deadlock? It does mean set[eu]id will have to wait of other threads and IO to complete... no matter how long that takes, but other than might it be reasonable? --cw