Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757195AbYFQR7U (ORCPT ); Tue, 17 Jun 2008 13:59:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758466AbYFQR7F (ORCPT ); Tue, 17 Jun 2008 13:59:05 -0400 Received: from qb-out-0506.google.com ([72.14.204.224]:43750 "EHLO qb-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755786AbYFQR7D (ORCPT ); Tue, 17 Jun 2008 13:59:03 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=Dgdh+YK/zm8EfzctYU2CPOBjENqZSgVoUkHb3d6k32SiWB3rUNftVwkIb3QGa5GohD SbKmD1XcaryfEp8rxp98NtiwO5pKEV7xRMwpYa6HC8XxBNoxd6GbcPfthum9VvUvV9co FGG7qlgh2uXKTiZuciAh1PGJosnY4LXdEh9XI= Message-ID: Date: Tue, 17 Jun 2008 19:59:00 +0200 From: "Michael Kerrisk" To: "Andrea Arcangeli" Subject: Re: PR_SET_SECCOMP and PR_GET_SECCOMP doc (and bug?) Cc: Valdis.Kletnieks@vt.edu, "Ivana Varekova" , lkml , linux-man@vger.kernel.org In-Reply-To: <20080617173411.GC28087@duo.random> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <48565951.40603@gmail.com> <20080616162543.GA9552@duo.random> <18697.1213719134@turing-police.cc.vt.edu> <20080617173411.GC28087@duo.random> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1875 Lines: 38 On Tue, Jun 17, 2008 at 7:34 PM, Andrea Arcangeli wrote: > On Tue, Jun 17, 2008 at 12:12:14PM -0400, Valdis.Kletnieks@vt.edu wrote: >> On Tue, 17 Jun 2008 15:32:29 +0200, Michael Kerrisk said: >> > On Mon, Jun 16, 2008 at 6:25 PM, Andrea Arcangeli wrote: >> > > On Mon, Jun 16, 2008 at 02:15:13PM +0200, Michael Kerrisk wrote: >> >> > >> PR_GET_SECCOMP (since Linux 2.6.23) >> > >> Return the secure computing mode of the calling thread. >> > >> Not very useful: if the caller is not in secure computing >> > >> mode, this operation returns 0; if the caller is in secure >> > >> computing mode, then the prctl() call will cause a SIGKILL >> > >> signal to be sent to the process. This operation is only >> > >> available if the kernel is configured with CONFIG_SECCOMP >> > >> enabled. >> >> Would it make sense to change the text to read "Not very useful for the >> current implementation of mode=1" and/or add that it may be useful for > > Yes, makes sense to me ;). I've made a change something like you suggest, Valdis. But I'm still not really convinced that it will be useful in the future. The problem is that as things stand, we would *never* be able to safely make the prctl(PR_GET_SECCOMP) call, since there is a chance (if mode is 1) that we would be killed by SIGKILL. -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ man-pages online: http://www.kernel.org/doc/man-pages/online_pages.html Found a bug? http://www.kernel.org/doc/man-pages/reporting_bugs.html -- 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/