Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752451AbaFERO4 (ORCPT ); Thu, 5 Jun 2014 13:14:56 -0400 Received: from mail-oa0-f53.google.com ([209.85.219.53]:36973 "EHLO mail-oa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751872AbaFEROx (ORCPT ); Thu, 5 Jun 2014 13:14:53 -0400 MIME-Version: 1.0 In-Reply-To: <1401975635-6162-1-git-send-email-drysdale@google.com> References: <1401975635-6162-1-git-send-email-drysdale@google.com> Date: Thu, 5 Jun 2014 10:14:52 -0700 X-Google-Sender-Auth: XRIXWnpz9N8r5L6GQ6jFM6t2EK4 Message-ID: Subject: Re: [PATCHv4 RESEND 0/3] syscalls,x86: Add execveat() system call From: Kees Cook To: David Drysdale Cc: Alexander Viro , Meredydd Luff , LKML , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Andrew Morton , Arnd Bergmann , "x86@kernel.org" , linux-arch@vger.kernel.org, linux-api@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 5, 2014 at 6:40 AM, David Drysdale wrote: > Resending, adding cc:linux-api. > > Also, it may help to add a little more background -- this patch is > needed as a (small) part of implementing Capsicum in the Linux kernel. > > Capsicum is a security framework that has been present in FreeBSD since > version 9.0 (Jan 2012), and is based on concepts from object-capability > security [1]. > > One of the features of Capsicum is capability mode, which locks down > access to global namespaces such as the filesystem hierarchy. In > capability mode, /proc is thus inaccessible and so fexecve(3) doesn't > work -- hence the need for a kernel-space alternative. > > [1] http://www.cl.cam.ac.uk/research/security/capsicum/papers/2010usenix-security-capsicum-website.pdf Thanks for reposting! I think it'd be quite helpful to have this available for very tightly confined sandboxes. And in a larger sense, Capsicum itself is an interesting way to do programmatic isolation. -Kees -- Kees Cook Chrome OS Security -- 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/