Re: [PATCH xfstests 2/2] overlay: test chattr lower file in overlay

[Eryu Guan <eguan@redhat.com>]

On Thu, Sep 14, 2017 at 08:04:03PM +0800, zhangyi (F) wrote:
> chattr with [iap..] attributes open file for read-only and
> invoke ioctl(). If we chattr a lower file in overlay, it
> will get the lower file but not trigger copy-up, so ioctl()
> lead to modification of that lower file incorrectly. Add this
> test for this case.
> 
> Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
> ---
>  tests/overlay/040     | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++
>  tests/overlay/040.out |  2 ++
>  tests/overlay/group   |  1 +
>  3 files changed, 92 insertions(+)
>  create mode 100755 tests/overlay/040
>  create mode 100644 tests/overlay/040.out
> 
> diff --git a/tests/overlay/040 b/tests/overlay/040
> new file mode 100755
> index 0000000..4d0c7ef
> --- /dev/null
> +++ b/tests/overlay/040
> @@ -0,0 +1,89 @@
> +#! /bin/bash
> +# FS QA Test 040
> +#
> +# chattr with [iap..] attributes open file for read-only and
> +# invoke ioctl(). If we chattr a lower file in overlay, it
> +# will get the lower file but not trigger copy-up, so ioctl()
> +# lead to modification of that lower file.
> +#
> +# Upstream Commit 7c6893e3c9ab ("ovl: don't allow writing
> +# ioctl on lower layer") return EPERM for this case to avoid
> +# this issue.
> +#
> +#-----------------------------------------------------------------------
> +# Copyright (c) 2017 Huawei.  All Rights Reserved.
> +# Author: zhangyi (F) <yi.zhang@huawei.com>
> +#
> +# This program is free software; you can redistribute it and/or
> +# modify it under the terms of the GNU General Public License as
> +# published by the Free Software Foundation.
> +#
> +# This program is distributed in the hope that it would be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program; if not, write the Free Software Foundation,
> +# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
> +#-----------------------------------------------------------------------
> +#
> +
> +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 /
> +	$CHATTR_PROG -i $lowerdir/foo
> +	rm -f $tmp.*
> +}
> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +
> +# remove previous $seqres.full before test
> +rm -f $seqres.full
> +
> +# real QA test starts here
> +_supported_fs overlay
> +_supported_os Linux
> +_require_scratch
> +_require_chattr i
> +
> +# remove all files from previous runs
> +_scratch_mkfs
> +
> +# prepare lower test file
> +lowerdir=$OVL_BASE_SCRATCH_MNT/$OVL_LOWER
> +mkdir -p $lowerdir
> +touch $lowerdir/foo
> +
> +# mounting overlay
> +_scratch_mount
> +
> +# Try to add immutable attributes in overlay, it will
> +# open file for read-only and invoke ioctl(), it should not
> +# modify lower origin file.
> +$CHATTR_PROG +i $SCRATCH_MNT/foo > /dev/null 2>&1
> +
> +$UMOUNT_PROG $SCRATCH_MNT
> +
> +# touching origin file in lower, should succeed
> +touch $lowerdir/foo > /dev/null 2>&1
> +
> +if [ $? -ne 0 ]; then
> +        echo "Test Fail, immutable attributes is modified in lower."
> +fi

No need to check return value of 'touch', a bare 'touch $lowerdir/foo'
would work, if touch failed the error message would break the golden
image. I can fix it at commit time. Thanks for the tests!

Eryu

> +
> +# success, all done
> +echo "Silence is golden"
> +status=0
> +exit
> diff --git a/tests/overlay/040.out b/tests/overlay/040.out
> new file mode 100644
> index 0000000..9e3d4d9
> --- /dev/null
> +++ b/tests/overlay/040.out
> @@ -0,0 +1,2 @@
> +QA output created by 040
> +Silence is golden
> diff --git a/tests/overlay/group b/tests/overlay/group
> index 39177c4..4cd4af1 100644
> --- a/tests/overlay/group
> +++ b/tests/overlay/group
> @@ -42,3 +42,4 @@
>  037 auto quick mount
>  038 auto quick copyup
>  039 auto quick
> +040 auto quick
> -- 
> 2.5.0
> 
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