From patchwork Mon Oct 1 08:29:52 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anand Jain X-Patchwork-Id: 10621699 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 042A8188F for ; Mon, 1 Oct 2018 08:31:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E760129440 for ; Mon, 1 Oct 2018 08:30:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E5EAD2947E; Mon, 1 Oct 2018 08:30:59 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 556F729440 for ; Mon, 1 Oct 2018 08:30:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728847AbeJAPG5 (ORCPT ); Mon, 1 Oct 2018 11:06:57 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:39126 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728803AbeJAPG4 (ORCPT ); Mon, 1 Oct 2018 11:06:56 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w918T976101190; Mon, 1 Oct 2018 08:30:21 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id; s=corp-2018-07-02; bh=3EPdNsodAtSnq6j1kEExAyzsAbS+cjNLBG6Z2xU3mW0=; b=DcRXe/yK2ZLYlOOKm+0xJzOf8EJv6fA6jbf8dXIjWQdHz/UUvEyYi59DGEeVrEpRJ9Kv dMximF1eiejt+4P/hYYuwxc3ZL1OqWFgjHaCnKTatXgkxBLMFrV7M0RW23QuBnvnmvTZ tLa2i0uiLqOcLC3KQ5EiVbZ+dV7S9QotF+3vDdNtlFF/klmx42kBVghk1UcTSse0e0Lo hjsu83aaYrMJnypZ6qFSnyrjLRXMU+rTirYM78e7R6ckOouu0cOtOmdlFoWMGk5LLX6I wNhtktL82H8BpQVu7faL4EegyRJ7hoOjDOf0TJi36eZZ+Ytt35PUUxLv7GiNvecVMC3R 4A== Received: from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71]) by aserp2120.oracle.com with ESMTP id 2mt1bpnfc9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 01 Oct 2018 08:30:20 +0000 Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w918UJ7g005424 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 1 Oct 2018 08:30:19 GMT Received: from abhmp0004.oracle.com (abhmp0004.oracle.com [141.146.116.10]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id w918UJ9P006225; Mon, 1 Oct 2018 08:30:19 GMT Received: from tpasj.sg.oracle.com (/10.186.53.176) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 01 Oct 2018 01:30:19 -0700 From: Anand Jain To: fstests@vger.kernel.org Cc: linux-btrfs@vger.kernel.org Subject: [PATCH] verify hardening agaist duplicate fsid Date: Mon, 1 Oct 2018 16:29:52 +0800 Message-Id: <1538382592-1632-1-git-send-email-anand.jain@oracle.com> X-Mailer: git-send-email 1.8.3.1 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9032 signatures=668707 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810010087 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Its not that impossible to imagine that a device OR a btrfs image is been copied just by using the dd or the cp command. Which in case both the copies of the btrfs will have the same fsid. If on the system with automount enabled, the copied FS gets scanned. We have a known bug in btrfs, that we let the device path be changed after the device has been mounted. So using this loop hole the new copied device would appears as if its mounted immediately after its been copied. For example: Initially.. /dev/mmcblk0p4 is mounted as / lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT mmcblk0 179:0 0 29.2G 0 disk |-mmcblk0p4 179:4 0 4G 0 part / |-mmcblk0p2 179:2 0 500M 0 part /boot |-mmcblk0p3 179:3 0 256M 0 part [SWAP] `-mmcblk0p1 179:1 0 256M 0 part /boot/efi btrfs fi show Label: none uuid: 07892354-ddaa-4443-90ea-f76a06accaba Total devices 1 FS bytes used 1.40GiB devid 1 size 4.00GiB used 3.00GiB path /dev/mmcblk0p4 Copy mmcblk0 to sda dd if=/dev/mmcblk0 of=/dev/sda And immediately after the copy completes the change in the device superblock is notified which the automount scans using btrfs device scan and the new device sda becomes the mounted root device. lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 1 14.9G 0 disk |-sda4 8:4 1 4G 0 part / |-sda2 8:2 1 500M 0 part |-sda3 8:3 1 256M 0 part `-sda1 8:1 1 256M 0 part mmcblk0 179:0 0 29.2G 0 disk |-mmcblk0p4 179:4 0 4G 0 part |-mmcblk0p2 179:2 0 500M 0 part /boot |-mmcblk0p3 179:3 0 256M 0 part [SWAP] `-mmcblk0p1 179:1 0 256M 0 part /boot/efi btrfs fi show / Label: none uuid: 07892354-ddaa-4443-90ea-f76a06accaba Total devices 1 FS bytes used 1.40GiB devid 1 size 4.00GiB used 3.00GiB path /dev/sda4 The bug is quite nasty that you can't either unmount /dev/sda4 or /dev/mmcblk0p4. And the problem does not get solved until you take the sda out of the system on to another system to change its fsid using the 'btrfstune -u' command. Signed-off-by: Anand Jain --- tests/btrfs/173 | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++ tests/btrfs/173.out | 5 ++++ tests/btrfs/group | 1 + 3 files changed, 76 insertions(+) create mode 100755 tests/btrfs/173 create mode 100644 tests/btrfs/173.out diff --git a/tests/btrfs/173 b/tests/btrfs/173 new file mode 100755 index 000000000000..c644b07d6f5b --- /dev/null +++ b/tests/btrfs/173 @@ -0,0 +1,70 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2018 Oracle. All Rights Reserved. +# +# FS QA Test 173 +# +# Fuzzy test for FS image duplication. +# +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +here=`pwd` +tmp=/tmp/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +_cleanup() +{ + cd / + rm -f $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# remove previous $seqres.full before test +rm -f $seqres.full + +# real QA test starts here + +# Modify as appropriate. +_supported_fs btrfs +_supported_os Linux +_require_scratch_dev_pool 2 +_scratch_dev_pool_get 2 + +dev_foo=$(echo $SCRATCH_DEV_POOL | awk '{print $1}' | rev | cut -d"/" -f1 | rev) +dev_bar=$(echo $SCRATCH_DEV_POOL | awk '{print $2}' | rev | cut -d"/" -f1 | rev) + +_mkfs_dev /dev/$dev_foo +_mount /dev/$dev_foo $SCRATCH_MNT + +echo mount before btrfs image clone | tee -a $seqres.full +findmnt /dev/$dev_foo | grep -v TARGET | awk '{print $1" "$2}' | \ + sed -e "s/$dev_foo/dev_foo/g" | _filter_scratch | tee -a $seqres.full +findmnt /dev/$dev_bar | grep -v TARGET | awk '{print $1" "$2}' | \ + sed -e "s/$dev_bar/dev_bar/g" | _filter_scratch | tee -a $seqres.full + +for sb_bytenr in 65536 67108864 +do + echo -n "dd status=none if=/dev/$dev_foo of=/dev/$dev_bar bs=1 "\ + "seek=$sb_bytenr skip=$sb_bytenr count=4096" >> $seqres.full + dd status=none if=/dev/$dev_foo of=/dev/$dev_bar bs=1 seek=$sb_bytenr \ + skip=$sb_bytenr count=4096 >> $seqres.full 2>&1 + echo ..:$? >> $seqres.full +done + +echo mount after btrfs image clone | tee -a $seqres.full +findmnt /dev/$dev_foo | grep -v TARGET | awk '{print $1" "$2}' | \ + sed -e "s/$dev_foo/dev_foo/g" | _filter_scratch | tee -a $seqres.full +findmnt /dev/$dev_bar | grep -v TARGET | awk '{print $1" "$2}' | \ + sed -e "s/$dev_bar/dev_bar/g" | _filter_scratch | tee -a $seqres.full + +_scratch_dev_pool_put + +# success, all done +status=0 +exit diff --git a/tests/btrfs/173.out b/tests/btrfs/173.out new file mode 100644 index 000000000000..a2ef7a26f4b9 --- /dev/null +++ b/tests/btrfs/173.out @@ -0,0 +1,5 @@ +QA output created by 173 +mount before btrfs image clone +SCRATCH_MNT /dev/dev_foo +mount after btrfs image clone +SCRATCH_MNT /dev/dev_foo diff --git a/tests/btrfs/group b/tests/btrfs/group index 45782565c3b7..b2f1393f3e97 100644 --- a/tests/btrfs/group +++ b/tests/btrfs/group @@ -175,3 +175,4 @@ 170 auto quick snapshot 171 auto quick qgroup 172 auto quick punch +173 volume