tests/overlay/027

#! /bin/bash
# FS QA Test 027
#
# If underlying upper file is immutable, it should stays
# untouchable in the overlayfs mount.
#
# Kernel commit below fixed it.
# f2b20f6ee842 vfs: move permission checking into ...
#
# This reproducer was originally written by
#     Miklos Szeredi <mszeredi@redhat.com>
#
#-----------------------------------------------------------------------
# Copyright (c) 2017 Red Hat Inc.  All Rights Reserved.
#
# 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 $upperdir/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

# Modify as appropriate.
_supported_fs overlay
_supported_os Linux
_require_scratch
_require_chattr i

# Remove all files from previous tests
_scratch_mkfs

# Preparing immutable file
upperdir=$OVL_BASE_SCRATCH_MNT/$OVL_UPPER
mkdir -p $upperdir
touch $upperdir/foo
$CHATTR_PROG +i $upperdir/foo

# Mounting overlay
_scratch_mount

# Touching immutable file in overlay, should fail.
# Not filtering output here because of errno returned
# varies among kernel versions:
#   touch: setting times of 'foo': Operation not permitted
#   touch: cannot touch 'foo': Permission denied
if touch $SCRATCH_MNT/foo > /dev/null 2>&1 ; then
	echo "Test Fail, you can't change an immutable file"
else
	echo "Silence is golden"
fi

# success, all done
status=0
exit