Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932072AbbKQRGF (ORCPT ); Tue, 17 Nov 2015 12:06:05 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:51471 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751966AbbKQRGB (ORCPT ); Tue, 17 Nov 2015 12:06:01 -0500 Date: Tue, 17 Nov 2015 17:05:56 +0000 From: Al Viro To: Seth Forshee Cc: "Eric W. Biederman" , linux-bcache@vger.kernel.org, dm-devel@redhat.com, linux-raid@vger.kernel.org, linux-mtd@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@tycho.nsa.gov, Serge Hallyn , Andy Lutomirski , linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 0/7] User namespace mount updates Message-ID: <20151117170556.GV22011@ZenIV.linux.org.uk> References: <1447778351-118699-1-git-send-email-seth.forshee@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1447778351-118699-1-git-send-email-seth.forshee@canonical.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1270 Lines: 27 On Tue, Nov 17, 2015 at 10:39:03AM -0600, Seth Forshee wrote: > Hi Eric, > > Here's another update to my patches for user namespace mounts, based on > your for-testing branch. These patches add safeguards necessary to allow > unprivileged mounts and update SELinux and Smack to safely handle > device-backed mounts from unprivileged users. > > The v2 posting received very little in the way of feedback, so changes > are minimal. I've made a trivial style change to the Smack changes at > Casey's request, and I've added Stephen's ack for the SELinux changes. Would you mind explaining which filesystem types do you plan to allow? SELinux and the rest of Linux S&M bunch do fuck-all for attacks via handcrafted fs image fed to the code in fs driver that does not expect a given kind of inconsistencies. As it is, validation of on-disk metadata is not particularly strong; what's more, protection against concurrent malicious *changes* of fs image (via direct writes by root) is simply inexistent. So what is that about? -- 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/