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=-0.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 09599C11F68 for ; Fri, 2 Jul 2021 13:29:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DF750613B4 for ; Fri, 2 Jul 2021 13:29:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232562AbhGBNc1 (ORCPT ); Fri, 2 Jul 2021 09:32:27 -0400 Received: from mout.gmx.net ([212.227.17.21]:54057 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230509AbhGBNc1 (ORCPT ); Fri, 2 Jul 2021 09:32:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1625232593; bh=0pPKDkUz1pPYTbB6hfJBMjr/11P2VHRbeLmqegK3/zY=; h=X-UI-Sender-Class:To:Cc:From:Subject:Date; b=SrET+NU6ZEKMOPDSL8b8swtsX0gRlQ/sh7aWRSATa72XC9pyxymAYz1ssd+eW+QmY 5LcCalVOoJBwTwOHmloiXe46pUh03sfSKOal+bTkEsMY6WpOPUvuqAQAK5AJOqE3HP TrGopGUmXW/WoXOwHzEfXsOGcA/AJusn7Enc3E2c= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [192.168.1.252] ([5.166.175.171]) by mail.gmx.net (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1MPXhK-1lcoXT1q2E-00McmL; Fri, 02 Jul 2021 15:29:53 +0200 To: linux-kernel@vger.kernel.org Cc: leah.rumancik@gmail.com From: "Artem S. Tashkinov" Subject: Re: [PATCH v4] ext4: wipe ext4_dir_entry2 upon file deletion Message-ID: Date: Fri, 2 Jul 2021 13:29:52 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:q/axTz+LtqflhB2k9qjeeIKnYaHhNyy6itvePialiEp4WZ8/Joe plzqCxqQYRmMBfKfRc8ukGehOCH3mQ1ugLm/2pr0VS0uNn0uVWGlb5VRbDVJofi0fnRNEJ5 xlRD7V9QqL3GWvoYXBIt5u9BC6RIFV2XFuLVFBdBXZHYZk59u+YneyZRTmiXX5pgbnnP0k0 7V0mDa64s7e28Bw11SKFw== X-UI-Out-Filterresults: notjunk:1;V03:K0:tU17AUReTxE=:Gk/MaCzY8Py6el0yGNhUiR 7aOTY71eUXIdnkC+pzoKfl51Ms7GdOPtfczgGzbSQ6O2tuQBFGKdAbjOBHHbsGwERWcsNNqVm OyL2pMaZPi61ko4FjyrtrD2KvnbXjdu97n+jcg5khnr/5/OAu1TMPuEKCDgmm9okBNrRph0zR tt+rSSSoVGbBb/Q8cT+eR5/ReOZYVU36NjXWvaRnUHIHUI5yrSgUyMPQHRCMc5LTiz9xhuJLj ibzPIuY08IrM1pANjgLZ90Sm7LXrelJK4OmljWmTJT/ByB0yHwB89Edh5yaueTmPtK6s1IHn/ W2Bp3q0aJ7E5aX3TQnWNEmL3MIbqU8M0GTkR3SpsG7pjF+vBi8g/qzpAUNRzqyCsIe/PRiQfe uM0WCEttjE9s/W/GFZwXQBXyIVkeHFsF570Shyit5eqqWsTBmYcOJuXj3B3WJgyQsBla4k3ps OGO41XXG2BMODPuj1j5UWmkRmekRXXPZ3em8SvDuX7E7w7+DiiBbMUuWH/kX2c9klZS199+4F DuvgphWGQf51UgI/JB1BFNQbrcV8x3ZrxFExZvIU2dxf3fvBpBnUEFMRHwFO1XM1Piu+o9phw TwRJJM+5GMHZ7MXzTYLpTQSu7UwQ6yyWZhOPM/ABoJ9YrPyLkhRTiFrxTIgfhsEJ/LUB34+4X lf6o8pNfkq8hv8flsumA3DJ1Weioko/OwWNRO6gXm95yN3DwatGgG434WKiu6aeZALXG344aZ 2NE9pa3DJuXKi6VaV53em18AfsJimDgNAC1Qbd/V6tpSiLR7hhu9in1252UuKHpRfpiDiGz5O 3xOu5QaJcRXzTjZPufqgDnk94exj1fLxDT/YJgZxs4JtYoS5ZAd4X45Z/7wi3hlZ/UOED1jmi WWtjk7dcJDKHxIiwrtBkRvsLanPeMPADtxjJ8ppPcL0fEplBsEvJTz7OU/GxUIra3HuMm3SEz m0uTgQZdDmDeD6ozpo31tqCdGuilPGElgoCANngj1DEVwFcXhKJI6WTYDgAbaoFlqDf4jW2xf w7ZdlOf4yIDv8lITxOU4vXB12ZNA02CuBJXd274Kzp5E5fxAYSaIN0y1/gDvLaKokaphYah8U 4TgEYWxtaihkYfOhkXemKxVWyUJVmkoixwU Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I'm curious about the nature of this feature. Does it make restoring accidentally deleted files more difficult or even impossible? OK, data remains but the patch description makes it sound like all the metadata is being wiped completely. > Upon file deletion, zero out all fields in ext4_dir_entry2 > besides rec_len. In case sensitive data is stored in filenames, > this ensures no potentially sensitive data is left in the directory > entry upon deletion. Also, wipe these fields upon moving a directory > entry during the conversion to an htree and when splitting htree > nodes. If it's the case, is it possible to make this new security feature user configurable? I'm OK with it being on by default but I'd be glad if there were a mount option to disable it. Best regards, Artem