From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757950Ab0DVU12 (ORCPT ); Thu, 22 Apr 2010 16:27:28 -0400 Received: from kroah.org ([198.145.64.141]:59564 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757773Ab0DVT77 (ORCPT ); Thu, 22 Apr 2010 15:59:59 -0400 X-Mailbox-Line: From gregkh@kvm.kroah.org Thu Apr 22 12:54:08 2010 Message-Id: <20100422195407.957633020@kvm.kroah.org> User-Agent: quilt/0.48-4.4 Date: Thu, 22 Apr 2010 12:53:29 -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, Wu Fengguang , Yan Zheng Subject: [032/139] readahead: fix NULL filp dereference In-Reply-To: <20100422195715.GA25490@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.33-stable review patch. If anyone has any objections, please let us know. ------------------ From: Wu Fengguang commit 70655c06bd3f25111312d63985888112aed15ac5 upstream. btrfs relocate_file_extent_cluster() calls us with NULL filp: [ 4005.426805] BUG: unable to handle kernel NULL pointer dereference at 00000021 [ 4005.426818] IP: [] page_cache_sync_readahead+0x18/0x3e Signed-off-by: Wu Fengguang Cc: Yan Zheng Reported-by: Kirill A. Shutemov Tested-by: Kirill A. Shutemov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/readahead.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/readahead.c +++ b/mm/readahead.c @@ -502,7 +502,7 @@ void page_cache_sync_readahead(struct ad return; /* be dumb */ - if (filp->f_mode & FMODE_RANDOM) { + if (filp && (filp->f_mode & FMODE_RANDOM)) { force_page_cache_readahead(mapping, filp, offset, req_size); return; }