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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham 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 4C324C3A59B for ; Fri, 30 Aug 2019 16:42:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2865A2087F for ; Fri, 30 Aug 2019 16:42:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728324AbfH3Qmt (ORCPT ); Fri, 30 Aug 2019 12:42:49 -0400 Received: from outbound.smtp.vt.edu ([198.82.183.121]:45086 "EHLO omr1.cc.vt.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728246AbfH3Qms (ORCPT ); Fri, 30 Aug 2019 12:42:48 -0400 Received: from mr4.cc.vt.edu (mail.ipv6.vt.edu [IPv6:2607:b400:92:9:0:9d:8fcb:4116]) by omr1.cc.vt.edu (8.14.4/8.14.4) with ESMTP id x7UGglAQ012145 for ; Fri, 30 Aug 2019 12:42:47 -0400 Received: from mail-qk1-f198.google.com (mail-qk1-f198.google.com [209.85.222.198]) by mr4.cc.vt.edu (8.14.7/8.14.7) with ESMTP id x7UGggVe004889 for ; Fri, 30 Aug 2019 12:42:47 -0400 Received: by mail-qk1-f198.google.com with SMTP id o4so7932580qkg.11 for ; Fri, 30 Aug 2019 09:42:47 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:mime-version:date :message-id; bh=AMywH1n1mw6t5p5hLpZTz0Q6W8htDSaR2tsRwWJpbB4=; b=PSM0hXySuyUo6FKNwnQhhJFozdU56VrY6V6ER239OAV7JMKT1OdM1MCwcI+loqEOp8 qJs4u/Mt7Tn7rxya7cFPwwcIdsiDLEEfPp3bx0cglCAOdHHroNImF72JVdlBP6iv91uZ UmphT6fOkg+WyFuEOtCftm59BGtK1B5/LYNuIpiYmZritVbM/cLIBitRkQaGNP+aJS01 FY/lLLsUMUC4xum2pxwnnBm7PJUh3Ck0PYs8yc6JCZKDSI/qamnS7og1gUafdwQHX7LU 9EYocYUZTEB1NtLisrDNFisv43BU+pawdfqan2jd6he2QjI2b4iVtTOja/CrrYG71Ztt OInQ== X-Gm-Message-State: APjAAAWXxYDwc2O/UGhPmmJp7qzSm54HgTxjtLajvfmtSGZ+gkO4/g3+ 5/PATHZgLRXimSQKwZzUStlkPtPc1MXAV7bzcP1rMFtwLjhNGZoL2gfVXpOfcb6iRa7g84VSicT 9TezUP36NeYY2oSKRte/55IcQ0ZJVY32usPw= X-Received: by 2002:ac8:120c:: with SMTP id x12mr8899872qti.315.1567183361985; Fri, 30 Aug 2019 09:42:41 -0700 (PDT) X-Google-Smtp-Source: APXvYqwaY2l4b6tk1M6trceqg9AZjRhcMlNGwJvpCK2NExWnBnD86JM81kuWaQfA7O5TUsj17REnaA== X-Received: by 2002:ac8:120c:: with SMTP id x12mr8899847qti.315.1567183361693; Fri, 30 Aug 2019 09:42:41 -0700 (PDT) Received: from turing-police ([2601:5c0:c001:4340::ba0]) by smtp.gmail.com with ESMTPSA id f27sm2703076qkl.25.2019.08.30.09.42.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 Aug 2019 09:42:40 -0700 (PDT) From: "Valdis =?utf-8?Q?Kl=c4=93tnieks?=" X-Google-Original-From: "Valdis =?utf-8?Q?Kl=c4=93tnieks?=" X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: Greg Kroah-Hartman , Sasha Levin , Christoph Hellwig cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] drivers/staging/exfat - by default, prohibit mount of fat/vfat Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 30 Aug 2019 12:42:39 -0400 Message-ID: <245727.1567183359@turing-police> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Concerns have been raised about the exfat driver accidentally mounting fat/vfat file systems. Add an extra configure option to help prevent that. Suggested-by: Christoph Hellwig Signed-off-by: Valdis Kletnieks diff --git a/drivers/staging/exfat/Kconfig b/drivers/staging/exfat/Kconfig index 78b32aa2ca19..1df177b1dc72 100644 --- a/drivers/staging/exfat/Kconfig +++ b/drivers/staging/exfat/Kconfig @@ -4,6 +4,14 @@ config EXFAT_FS help This adds support for the exFAT file system. +config EXFAT_DONT_MOUNT_VFAT + bool "Prohibit mounting of fat/vfat filesysems by exFAT" + default y + help + By default, the exFAT driver will only mount exFAT filesystems, and refuse + to mount fat/vfat filesystems. Set this to 'n' to allow the exFAT driver + to mount these filesystems. + config EXFAT_DISCARD bool "enable discard support" depends on EXFAT_FS diff --git a/drivers/staging/exfat/exfat_super.c b/drivers/staging/exfat/exfat_super.c index 5b5c2ca8c9aa..7fdb5b8bc928 100644 --- a/drivers/staging/exfat/exfat_super.c +++ b/drivers/staging/exfat/exfat_super.c @@ -486,10 +486,16 @@ static int ffsMountVol(struct super_block *sb) break; if (i < 53) { +#ifdef CONFIG_EXFAT_DONT_MOUNT_VFAT + ret = -EINVAL; + printk(KERN_INFO "EXFAT: Attempted to mount VFAT filesystem\n"); + goto out; +#else if (GET16(p_pbr->bpb + 11)) /* num_fat_sectors */ ret = fat16_mount(sb, p_pbr); else ret = fat32_mount(sb, p_pbr); +#endif } else { ret = exfat_mount(sb, p_pbr); }