Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754350Ab3IXQvG (ORCPT ); Tue, 24 Sep 2013 12:51:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:8593 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753570Ab3IXQvE (ORCPT ); Tue, 24 Sep 2013 12:51:04 -0400 Date: Tue, 24 Sep 2013 18:44:42 +0200 From: Oleg Nesterov To: Richard Guy Briggs Cc: John Johansen , linux-kernel@vger.kernel.org Subject: Re: [PATCH] apparmor: remove the "task" arg from may_change_ptraced_domain() Message-ID: <20130924164442.GB4036@redhat.com> References: <20130916142035.GA26661@redhat.com> <20130923215214.GV13968@madcap2.tricolour.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130923215214.GV13968@madcap2.tricolour.ca> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 925 Lines: 30 On 09/23, Richard Guy Briggs wrote: > > On Mon, Sep 16, 2013 at 04:20:35PM +0200, Oleg Nesterov wrote: > > Unless task == current ptrace_parent(task) is not safe even under > > rcu_read_lock() and most of the current users are not right. > > Could you point to an explanation of this? If this task exits before rcu_read_lock() ->parent can point to the already freed/reused memory. (in the long term we should probably clear ->parent/real_parent/group_leader/more in __unhash_process(), but lets not discuss this right now ;) > (Did you send a patch to fix the selinux hook?) No, sorry, I was sick. Will do. > Acked-by: Richard Guy Briggs Thanks! Oleg. -- 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/