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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41955CA0FFC for ; Sat, 2 Sep 2023 08:20:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235362AbjIBIUC (ORCPT ); Sat, 2 Sep 2023 04:20:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229475AbjIBIUC (ORCPT ); Sat, 2 Sep 2023 04:20:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5FAC1CC for ; Sat, 2 Sep 2023 01:19:59 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B6BA1601CF for ; Sat, 2 Sep 2023 08:19:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C3E0DC433C7; Sat, 2 Sep 2023 08:19:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1693642798; bh=H0jZqmHxH11HljCzA78hnoFPkjwFhKanZixbXINjobs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rkWAQIBxh+9EERTp4a5XHaPfTjO6yHFovioiIz4JRZdC5nZbd4AZAWgpnVrOxiPje HJZHuq6I0x2SAN5cRKt6SNZfiV5RipnFdhuauEJKpsMjn9Hrg17mz4lSMhc/wtryfK JIrAhbfd7ZCu3Z2GB283X6ctWfFO5ugSAY5dqWX8= Date: Sat, 2 Sep 2023 10:19:55 +0200 From: Greg Kroah-Hartman To: Gao Xiang Cc: stable@vger.kernel.org, linux-erofs@lists.ozlabs.org, keltargw Subject: Re: [PATCH 6.5.y] erofs: ensure that the post-EOF tails are all zeroed Message-ID: <2023090247-consonant-hangnail-ef8c@gregkh> References: <20230831112959.99884-1-hsiangkao@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230831112959.99884-1-hsiangkao@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Thu, Aug 31, 2023 at 07:29:53PM +0800, Gao Xiang wrote: > commit e4c1cf523d820730a86cae2c6d55924833b6f7ac upstream. > > This was accidentally fixed up in commit e4c1cf523d82 but we can't > take the full change due to other dependancy issues, so here is just > the actual bugfix that is needed. > > [Background] > > keltargw reported an issue [1] that with mmaped I/Os, sometimes the > tail of the last page (after file ends) is not filled with zeroes. > > The root cause is that such tail page could be wrongly selected for > inplace I/Os so the zeroed part will then be filled with compressed > data instead of zeroes. > > A simple fix is to avoid doing inplace I/Os for such tail parts, > actually that was already fixed upstream in commit e4c1cf523d82 > ("erofs: tidy up z_erofs_do_read_page()") by accident. > > [1] https://lore.kernel.org/r/3ad8b469-25db-a297-21f9-75db2d6ad224@linux.alibaba.com > > Reported-by: keltargw > Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support") > Signed-off-by: Gao Xiang > --- > fs/erofs/zdata.c | 2 ++ > 1 file changed, 2 insertions(+) All now queued up, thanks. greg k-h