From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932237Ab1HCXdl (ORCPT ); Wed, 3 Aug 2011 19:33:41 -0400 Received: from cantor2.suse.de ([195.135.220.15]:34212 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756322Ab1HCXbC (ORCPT ); Wed, 3 Aug 2011 19:31:02 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Aug 3 15:12:53 2011 Message-Id: <20110803221253.336284856@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 03 Aug 2011 15:01:52 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, John Johansen Subject: [092/102] AppArmor: Fix reference to rcu protected pointer outside of rcu_read_lock In-Reply-To: <20110803221345.GA10346@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let us know. ------------------ From: John Johansen commit 04fdc099f9c80c7775dbac388fc97e156d4d47e7 upstream. The pointer returned from tracehook_tracer_task() is only valid inside the rcu_read_lock. However the tracer pointer obtained is being passed to aa_may_ptrace outside of the rcu_read_lock critical section. Mover the aa_may_ptrace test into the rcu_read_lock critical section, to fix this. Kernels affected: 2.6.36 - 3.0 Reported-by: Oleg Nesterov Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman --- security/apparmor/domain.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -73,7 +73,6 @@ static int may_change_ptraced_domain(str cred = get_task_cred(tracer); tracerp = aa_cred_profile(cred); } - rcu_read_unlock(); /* not ptraced */ if (!tracer || unconfined(tracerp)) @@ -82,6 +81,7 @@ static int may_change_ptraced_domain(str error = aa_may_ptrace(tracer, tracerp, to_profile, PTRACE_MODE_ATTACH); out: + rcu_read_unlock(); if (cred) put_cred(cred);