mirror_qemu/tests/qemu-iotests/tests/file-io-error

#!/usr/bin/env bash
# group: rw
#
# Produce an I/O error in file-posix, and hope that it is not catastrophic.
# Regression test for: https://bugzilla.redhat.com/show_bug.cgi?id=2234374
#
# Copyright (C) 2023 Red Hat, Inc.
#
# 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; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will 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, see <http://www.gnu.org/licenses/>.
#

seq=$(basename "$0")
echo "QA output created by $seq"

status=1	# failure is the default!

_cleanup()
{
    _cleanup_qemu
    rm -f "$TEST_DIR/fuse-export"
}
trap "_cleanup; exit \$status" 0 1 2 3 15

# get standard environment, filters and checks
. ../common.rc
. ../common.filter
. ../common.qemu

# Format-agnostic (we do not use any), but we do test the file protocol
_supported_proto file
_require_drivers blkdebug null-co

if [ "$IMGOPTSSYNTAX" = "true" ]; then
    # We need `$QEMU_IO -f file` to work; IMGOPTSSYNTAX uses --image-opts,
    # breaking -f.
    _unsupported_fmt $IMGFMT
fi

# This is a regression test of a bug in which flie-posix would access zone
# information in case of an I/O error even when there is no zone information,
# resulting in a division by zero.
# To reproduce the problem, we need to trigger an I/O error inside of
# file-posix, which can be done (rootless) by providing a FUSE export that
# presents only errors when accessed.

_launch_qemu
_send_qemu_cmd $QEMU_HANDLE \
    "{'execute': 'qmp_capabilities'}" \
    'return'

_send_qemu_cmd $QEMU_HANDLE \
    "{'execute': 'blockdev-add',
      'arguments': {
          'driver': 'blkdebug',
          'node-name': 'node0',
          'inject-error': [{'event': 'none'}],
          'image': {
              'driver': 'null-co'
          }
      }}" \
    'return'

# FUSE mountpoint must exist and be a regular file
touch "$TEST_DIR/fuse-export"

# The grep -v to filter fusermount's (benign) error when /etc/fuse.conf does
# not contain user_allow_other and the subsequent check for missing FUSE support
# have both been taken from iotest 308.
output=$(_send_qemu_cmd $QEMU_HANDLE \
    "{'execute': 'block-export-add',
      'arguments': {
          'id': 'exp0',
          'type': 'fuse',
          'node-name': 'node0',
          'mountpoint': '$TEST_DIR/fuse-export',
          'writable': true
      }}" \
    'return' \
    | grep -v 'option allow_other only allowed if')

if echo "$output" | grep -q "Parameter 'type' does not accept value 'fuse'"; then
    _notrun 'No FUSE support'
fi
echo "$output"

echo
# This should fail, but gracefully, i.e. just print an I/O error, not crash.
$QEMU_IO -f file -c 'write 0 64M' "$TEST_DIR/fuse-export" | _filter_qemu_io
echo

capture_events=BLOCK_EXPORT_DELETED _send_qemu_cmd $QEMU_HANDLE \
    "{'execute': 'block-export-del',
      'arguments': {'id': 'exp0'}}" \
    'return'

_wait_event $QEMU_HANDLE \
    'BLOCK_EXPORT_DELETED'

_send_qemu_cmd $QEMU_HANDLE \
    "{'execute': 'blockdev-del',
      'arguments': {'node-name': 'node0'}}" \
    'return'

# success, all done
echo "*** done"
rm -f $seq.full
status=0