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 3727FC433EF for ; Wed, 9 Feb 2022 15:59:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236407AbiBIP7t (ORCPT ); Wed, 9 Feb 2022 10:59:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236398AbiBIP7t (ORCPT ); Wed, 9 Feb 2022 10:59:49 -0500 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 47F40C0613C9 for ; Wed, 9 Feb 2022 07:59:52 -0800 (PST) Received: by mail-wr1-x429.google.com with SMTP id s18so4853180wrv.7 for ; Wed, 09 Feb 2022 07:59:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=Wf8pBHPnIbwBS8l1ga7IlePPb2NVs+dEhjuVljUBPL0=; b=uoZQFZFTh4MWC1dtmAROvUGhJHmAVYXfRYOAWo8gKyK62YWvPbxBb/FtR7u0hgWHM+ pIHKzcAPIBus0KV7+mL3D5j14qeOkWhNlhbJ27iaSBhTl/LjI4HHKacQLeaP0W27kYi4 S3IY7DwzPAuE8oLpegUUjChlpPOLw2uSQqJ+5BKLAuffbk7cd8egzMzWrTEY9KtgoRa8 lhCJFlR9ZXDT3UoxC0gXTD0HcsmKfyMcum4z3NXlytG7Avl6gstXNUE/R3zGzn6Ti6rI nfSuSby+RBkqpUK/2NHWt/I4qhdA9CqPByEjJEcUJtu45v7exquNrCxUmMMhRNRl4LwZ 9QKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=Wf8pBHPnIbwBS8l1ga7IlePPb2NVs+dEhjuVljUBPL0=; b=6A5PZlwcJL7ZI65z6pq0J9puv5+7bbH1JuGR4DeIGX/V8If/IOtjw40ZuFI7w8mwuo uhmOa3kWg9aV0B9j4MIIiDSw9fdRu0Am0QW44somqJ38omLmlygCaET2p28D13xqGpVW 68PrduIUupH/w7drxxC4isXq3zqZWcogQSkYTrJ54KvhmAhDxVvjCQ5eDjhblNYFDet2 xg2qA0lagWbosQ8UCOAEIfp/Iw9KOn0sFIAuTpOLACcAS+npsVx8wHV6mxG95wX7vUL8 OUjH9UCD+/DpV2/BcGvcmDXFJ4efe/LuSAvdeUEWI0qvRzSJ3I63iTCdikPGNyLPUKW+ m/7A== X-Gm-Message-State: AOAM533AJo7+j2hka6/wSI2Hikam/P6APdPYwqh8JiK+gzCz65glzEbI WN7zR/GCd56EtpRBwROcIj8Fhg== X-Google-Smtp-Source: ABdhPJzrsU/yGaq1wonWpTsPZOGFI2x3Kw84cs8UYaEe/84fhhkIxX9wA9KdK4C49JCW0SYDnFQlaw== X-Received: by 2002:a05:6000:1548:: with SMTP id 8mr2519928wry.504.1644422390765; Wed, 09 Feb 2022 07:59:50 -0800 (PST) Received: from google.com (cpc155339-bagu17-2-0-cust87.1-3.cable.virginm.net. [86.27.177.88]) by smtp.gmail.com with ESMTPSA id g22sm5098170wmh.7.2022.02.09.07.59.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Feb 2022 07:59:50 -0800 (PST) Date: Wed, 9 Feb 2022 15:59:48 +0000 From: Lee Jones To: Christoph Hellwig Cc: linux-kernel@vger.kernel.org, Stable , Dave Chinner , Goldwyn Rodrigues , "Darrick J . Wong" , Bob Peterson , Damien Le Moal , Theodore Ts'o , Andreas Gruenbacher , Ritesh Harjani , Johannes Thumshirn , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, cluster-devel@redhat.com, syzbot+0ed9f769264276638893@syzkaller.appspotmail.com Subject: Re: [PATCH 1/1] Revert "iomap: fall back to buffered writes for invalidation failures" Message-ID: References: <20220209085243.3136536-1-lee.jones@linaro.org> <20220209150904.GA22025@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220209150904.GA22025@lst.de> Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Wed, 09 Feb 2022, Christoph Hellwig wrote: > On Wed, Feb 09, 2022 at 08:52:43AM +0000, Lee Jones wrote: > > This reverts commit 60263d5889e6dc5987dc51b801be4955ff2e4aa7. > > > > Reverting since this commit opens a potential avenue for abuse. > > > > The C-reproducer and more information can be found at the link below. > > > > With this patch applied, I can no longer get the repro to trigger. > > Well, maybe you should actually debug and try to understand what is > going on before blindly reverting random commits. That is not a reasonable suggestion. Requesting that someone becomes an area expert on a huge and complex subject such as file systems (various) in order to fix your broken code is not rational. If you'd like to use the PoC provided as a basis to test your own solution, then go right ahead. However, as it stands this API should be considered to contain security risk and should be patched as quickly as can be mustered. Reversion of the offending commit seems to be the fastest method to achieve that currently. -- Lee Jones [李琼斯] Principal Technical Lead - Developer Services Linaro.org │ Open source software for Arm SoCs Follow Linaro: Facebook | Twitter | Blog