From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266481AbUHUPBP (ORCPT ); Sat, 21 Aug 2004 11:01:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266477AbUHUPBP (ORCPT ); Sat, 21 Aug 2004 11:01:15 -0400 Received: from mail5.ewetel.de ([212.6.122.32]:25508 "EHLO mail5.ewetel.de") by vger.kernel.org with ESMTP id S266481AbUHUPBM (ORCPT ); Sat, 21 Aug 2004 11:01:12 -0400 To: Joerg Schilling Cc: linux-kernel@vger.kernel.org Subject: Re: PATCH: cdrecord: avoiding scsi device numbering for ide devices In-Reply-To: <2vDtS-bq-19@gated-at.bofh.it> References: <2ptdY-42Y-55@gated-at.bofh.it> <2uPdM-380-11@gated-at.bofh.it> <2uUwL-6VP-11@gated-at.bofh.it> <2uWfh-8jo-29@gated-at.bofh.it> <2uXl0-Gt-27@gated-at.bofh.it> <2vge2-63k-15@gated-at.bofh.it> <2vgQF-6Ai-39@gated-at.bofh.it> <2vipq-7O8-15@gated-at.bofh.it> <2vj2b-8md-9@gated-at.bofh.it> <2vDtS-bq-19@gated-at.bofh.it> Date: Sat, 21 Aug 2004 17:01:03 +0200 Message-Id: From: Pascal Schmidt X-CheckCompat: OK Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 21 Aug 2004 14:50:08 +0200, you wrote in linux.kernel: > If the owners and permissions of the filesystem have been set up correctly, > then there is no security problem. The previous Linux implementation allowed users with *read* access to the device to send arbitrary SG_IO commands. Giving read permission to normal users is quite common, to allow them to run isosize or play their freshly burned SVCDs with mplayer. It violated the principle of least surprise that a user can screw the device without even having write permission. Yes, it breaks user-space programs, and yes, the kernel is to blame for its previous behavior, not user-space. However, now we need to get on, and going back to the previous behavior, which because the discussion is now a well-known security hole, is not an option. -- Ciao, Pascal