From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 934F0C54FD0 for ; Mon, 27 Apr 2020 02:27:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F742206DD for ; Mon, 27 Apr 2020 02:27:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726413AbgD0C1Q (ORCPT ); Sun, 26 Apr 2020 22:27:16 -0400 Received: from mail104.syd.optusnet.com.au ([211.29.132.246]:44773 "EHLO mail104.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726296AbgD0C1Q (ORCPT ); Sun, 26 Apr 2020 22:27:16 -0400 Received: from dread.disaster.area (pa49-195-157-175.pa.nsw.optusnet.com.au [49.195.157.175]) by mail104.syd.optusnet.com.au (Postfix) with ESMTPS id B80CF82167F; Mon, 27 Apr 2020 12:27:10 +1000 (AEST) Received: from dave by dread.disaster.area with local (Exim 4.92.3) (envelope-from ) id 1jStUD-0001QJ-Af; Mon, 27 Apr 2020 12:27:09 +1000 Date: Mon, 27 Apr 2020 12:27:09 +1000 From: Dave Chinner To: Matthew Wilcox Cc: Guoqing Jiang , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, hch@infradead.org, Mike Marshall , Martin Brandenburg , devel@lists.orangefs.org Subject: Re: [RFC PATCH 8/9] orangefs: use set/clear_fs_page_private Message-ID: <20200427022709.GC2005@dread.disaster.area> References: <20200426214925.10970-1-guoqing.jiang@cloud.ionos.com> <20200426214925.10970-9-guoqing.jiang@cloud.ionos.com> <20200426222455.GB2005@dread.disaster.area> <20200427001234.GB29705@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200427001234.GB29705@bombadil.infradead.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.3 cv=X6os11be c=1 sm=1 tr=0 a=ONQRW0k9raierNYdzxQi9Q==:117 a=ONQRW0k9raierNYdzxQi9Q==:17 a=kj9zAlcOel0A:10 a=cl8xLZFz6L8A:10 a=7-415B0cAAAA:8 a=_ZLPnNw1jSjQLjkGmAoA:9 a=CjuIK1q_8ugA:10 a=igBNqPyMv6gA:10 a=biEYGPWJfzWAr4FL6Ov7:22 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Apr 26, 2020 at 05:12:34PM -0700, Matthew Wilcox wrote: > On Mon, Apr 27, 2020 at 08:24:55AM +1000, Dave Chinner wrote: > > > @@ -460,17 +456,13 @@ static void orangefs_invalidatepage(struct page *page, > > > > > > if (offset == 0 && length == PAGE_SIZE) { > > > kfree((struct orangefs_write_range *)page_private(page)); > > > - set_page_private(page, 0); > > > - ClearPagePrivate(page); > > > - put_page(page); > > > + clear_fs_page_private(page); > > > > Ditto: > > wr = clear_fs_page_private(page); > > kfree(wr); > > You don't want to be as succinct as the btrfs change you suggested? > > kfree(clear_fs_page_private(page)); That could be done, yes. I was really just trying to point out the use after free that was occurring here rather than write compact code... Cheers, Dave. -- Dave Chinner david@fromorbit.com