Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751296AbWHISQI (ORCPT ); Wed, 9 Aug 2006 14:16:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751295AbWHISQI (ORCPT ); Wed, 9 Aug 2006 14:16:08 -0400 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:5576 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S1751292AbWHISQG (ORCPT ); Wed, 9 Aug 2006 14:16:06 -0400 Subject: Re: [RFC/PATCH] revoke/frevoke system calls V2 From: Alan Cox To: Edgar Toernig Cc: Pekka Enberg , Pavel Machek , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, akpm@osdl.org, viro@zeniv.linux.org.uk, tytso@mit.edu, tigran@veritas.com In-Reply-To: <20060809200019.0bd5eecd.froese@gmx.de> References: <20060805122936.GC5417@ucw.cz> <20060807101745.61f21826.froese@gmx.de> <84144f020608070251j2e14e909v8a18f62db85ff3d4@mail.gmail.com> <20060807224144.3bb64ac4.froese@gmx.de> <1155040157.5729.34.camel@localhost.localdomain> <20060809104155.48ad3c77.froese@gmx.de> <1155120128.5729.143.camel@localhost.localdomain> <20060809200019.0bd5eecd.froese@gmx.de> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Wed, 09 Aug 2006 19:35:48 +0100 Message-Id: <1155148549.5729.249.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.6.2 (2.6.2-1.fc5.5) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1007 Lines: 21 Ar Mer, 2006-08-09 am 20:00 +0200, ysgrifennodd Edgar Toernig: > And killing them is not OK? "fuser -km /dev/cdrom" already covers both > cases, mounted somewhere and opened for special access. fuser is quite easy to race, it doesn't handle all sorts of corner cases like namespaces either. Its a crude blunt instrument that sometimes works and is very slow. > Sorry if I sound a little bit anal. IMO, a generic revoke is a pretty > sharp sword which is given to ordinary users and I have a very uneasy > feeling. They can dig in the innards of other people's processes - a > clean headshot by root is something different ... I can see your concern about arbitary files, but I'm not sure it holds simply because the tricks already exist via other methods. - 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/