Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964882AbVIMQvN (ORCPT ); Tue, 13 Sep 2005 12:51:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964884AbVIMQvN (ORCPT ); Tue, 13 Sep 2005 12:51:13 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:32946 "EHLO ZenIV.linux.org.uk") by vger.kernel.org with ESMTP id S964882AbVIMQvL (ORCPT ); Tue, 13 Sep 2005 12:51:11 -0400 Date: Tue, 13 Sep 2005 17:51:02 +0100 From: Al Viro To: Linus Torvalds Cc: Sripathi Kodi , Andrew Morton , linux-kernel@vger.kernel.org, patrics@interia.pl, Ingo Molnar , Roland McGrath Subject: Re: [PATCH 2.6.13.1] Patch for invisible threads Message-ID: <20050913165102.GR25261@ZenIV.linux.org.uk> References: <4325BEF3.2070901@in.ibm.com> <20050912134954.7bbd15b2.akpm@osdl.org> <4326CFE2.6000908@in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1222 Lines: 31 On Tue, Sep 13, 2005 at 07:53:40AM -0700, Linus Torvalds wrote: > So this patch is _wrong_. Definitely. > I think the problem is "proc_check_root()", which just refuses to do a lot > of things without a fs. Many of those things are unnecessary, afaik - we > should allow it. But allowing it means that some other paths may need more > checking.. > > So you can _try_ to just make proc_check_root() return 0 when > proc_root_link() returns an error... I very much doubt the correctness of that. The real problem here is obvious: it's about permissions on /proc//task. That's where the things go wrong - we use proc_permission() for it and we have group leader as associated task. Note that stuff _in_ proc//task will keep working just fine, if we manage to get to it - there we have other threads as associated tasks, so everything works as it should. What we need is to decide what kind of access control do we really want on /proc//task. That's it. - 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/