Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756656AbXJBNdv (ORCPT ); Tue, 2 Oct 2007 09:33:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752170AbXJBNdn (ORCPT ); Tue, 2 Oct 2007 09:33:43 -0400 Received: from wine.ocn.ne.jp ([122.1.235.145]:59583 "EHLO smtp.wine.ocn.ne.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751213AbXJBNdm (ORCPT ); Tue, 2 Oct 2007 09:33:42 -0400 To: jmorris@namei.org Cc: linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, chrisw@sous-sol.org Subject: Re: [TOMOYO 14/15](repost) LSM expansion for TOMOYO Linux. From: Tetsuo Handa References: <4701F285.5000206@nttdata.co.jp> <4701F5CC.7040209@nttdata.co.jp> In-Reply-To: Message-Id: <200710022233.ICD81749.LJFFHOtOSVOFQM@I-love.SAKURA.ne.jp> X-Mailer: Winbiff [Version 2.50 PL2] X-Accept-Language: ja,en Date: Tue, 2 Oct 2007 22:33:40 +0900 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1221 Lines: 30 Hello. James Morris wrote: > Why do you need racy unlocked versions, in addition to the existing > security_task_kill() hook which is called safely via > check_kill_permission() ? TOMOYO Linux provides "delayed enforcing mode" which allows administrator judge interactively for requests that violated policy. Sometimes, especially after updating software packages, irregular behavior arise. So, the administrator prepares for such irregular behavior by invoking "ccs-queryd" userland program. The "ccs-queryd" prints the contents of policy violation and asks the administrator whether to grant the request that violated policy. This can reduce the possibility of "restarting process failed due to permission denied". Thus, security_task_kill() which is called with tasklist_lock held is not what TOMOYO Linux wants. I know this approach is racy, but TOMOYO Linux wants these unlocked versions to avoid failure due to permission denial caused by MAC's policy. Regards. - 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/