From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755323Ab1B1QhP (ORCPT ); Mon, 28 Feb 2011 11:37:15 -0500 Received: from kroah.org ([198.145.64.141]:41238 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755226Ab1B1QhI (ORCPT ); Mon, 28 Feb 2011 11:37:08 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Mon Feb 28 08:24:07 2011 Message-Id: <20110228162407.149097235@clark.kroah.org> User-Agent: quilt/0.48-11.2 Date: Mon, 28 Feb 2011 08:22:36 -0800 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, Tetsuo Handa , David Howells Subject: [15/68] CRED: Fix kernel panic upon security_file_alloc() failure. In-Reply-To: <20110228163502.GA27221@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Tetsuo Handa commit 78d2978874e4e10e97dfd4fd79db45bdc0748550 upstream. In get_empty_filp() since 2.6.29, file_free(f) is called with f->f_cred == NULL when security_file_alloc() returned an error. As a result, kernel will panic() due to put_cred(NULL) call within RCU callback. Fix this bug by assigning f->f_cred before calling security_file_alloc(). Signed-off-by: Tetsuo Handa Signed-off-by: David Howells Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/file_table.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/file_table.c +++ b/fs/file_table.c @@ -121,13 +121,13 @@ struct file *get_empty_filp(void) goto fail; percpu_counter_inc(&nr_files); + f->f_cred = get_cred(cred); if (security_file_alloc(f)) goto fail_sec; INIT_LIST_HEAD(&f->f_u.fu_list); atomic_long_set(&f->f_count, 1); rwlock_init(&f->f_owner.lock); - f->f_cred = get_cred(cred); spin_lock_init(&f->f_lock); eventpoll_init_file(f); /* f->f_version: 0 */