qemu-e2k/tests/qemu-iotests/056
Eric Blake b66ff2c298 iotests: Specify explicit backing format where sensible
There are many existing qcow2 images that specify a backing file but
no format.  This has been the source of CVEs in the past, but has
become more prominent of a problem now that libvirt has switched to
-blockdev.  With older -drive, at least the probing was always done by
qemu (so the only risk of a changed format between successive boots of
a guest was if qemu was upgraded and probed differently).  But with
newer -blockdev, libvirt must specify a format; if libvirt guesses raw
where the image was formatted, this results in data corruption visible
to the guest; conversely, if libvirt guesses qcow2 where qemu was
using raw, this can result in potential security holes, so modern
libvirt instead refuses to use images without explicit backing format.

The change in libvirt to reject images without explicit backing format
has pointed out that a number of tools have been far too reliant on
probing in the past.  It's time to set a better example in our own
iotests of properly setting this parameter.

iotest calls to create, rebase, and convert are all impacted to some
degree.  It's a bit annoying that we are inconsistent on command line
- while all of those accept -o backing_file=...,backing_fmt=..., the
shortcuts are different: create and rebase have -b and -F, while
convert has -B but no -F.  (amend has no shortcuts, but the previous
patch just deprecated the use of amend to change backing chains).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200706203954.341758-9-eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-14 15:18:59 +02:00

343 lines
14 KiB
Python
Executable File

#!/usr/bin/env python3
#
# Tests for drive-backup
#
# Copyright (C) 2013 Red Hat, Inc.
#
# Based on 041.
#
# 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/>.
#
import time
import os
import iotests
from iotests import qemu_img, qemu_io, create_image
backing_img = os.path.join(iotests.test_dir, 'backing.img')
test_img = os.path.join(iotests.test_dir, 'test.img')
target_img = os.path.join(iotests.test_dir, 'target.img')
def img_create(img, fmt=iotests.imgfmt, size='64M', **kwargs):
fullname = os.path.join(iotests.test_dir, '%s.%s' % (img, fmt))
optargs = []
for k,v in kwargs.items():
optargs = optargs + ['-o', '%s=%s' % (k,v)]
args = ['create', '-f', fmt] + optargs + [fullname, size]
iotests.qemu_img(*args)
return fullname
def try_remove(img):
try:
os.remove(img)
except OSError:
pass
def io_write_patterns(img, patterns):
for pattern in patterns:
iotests.qemu_io('-c', 'write -P%s %s %s' % pattern, img)
class TestSyncModesNoneAndTop(iotests.QMPTestCase):
image_len = 64 * 1024 * 1024 # MB
def setUp(self):
create_image(backing_img, TestSyncModesNoneAndTop.image_len)
qemu_img('create', '-f', iotests.imgfmt,
'-o', 'backing_file=%s' % backing_img, '-F', 'raw', test_img)
qemu_io('-c', 'write -P0x41 0 512', test_img)
qemu_io('-c', 'write -P0xd5 1M 32k', test_img)
qemu_io('-c', 'write -P0xdc 32M 124k', test_img)
qemu_io('-c', 'write -P0xdc 67043328 64k', test_img)
self.vm = iotests.VM().add_drive(test_img)
self.vm.launch()
def tearDown(self):
self.vm.shutdown()
os.remove(test_img)
os.remove(backing_img)
try:
os.remove(target_img)
except OSError:
pass
def test_complete_top(self):
self.assert_no_active_block_jobs()
result = self.vm.qmp('drive-backup', device='drive0', sync='top',
format=iotests.imgfmt, target=target_img)
self.assert_qmp(result, 'return', {})
self.wait_until_completed(check_offset=False)
self.assert_no_active_block_jobs()
self.vm.shutdown()
self.assertTrue(iotests.compare_images(test_img, target_img),
'target image does not match source after backup')
def test_cancel_sync_none(self):
self.assert_no_active_block_jobs()
result = self.vm.qmp('drive-backup', device='drive0',
sync='none', target=target_img)
self.assert_qmp(result, 'return', {})
time.sleep(1)
self.vm.hmp_qemu_io('drive0', 'write -P0x5e 0 512')
self.vm.hmp_qemu_io('drive0', 'aio_flush')
# Verify that the original contents exist in the target image.
event = self.cancel_and_wait()
self.assert_qmp(event, 'data/type', 'backup')
self.vm.shutdown()
time.sleep(1)
self.assertEqual(-1, qemu_io('-c', 'read -P0x41 0 512', target_img).find("verification failed"))
class TestBeforeWriteNotifier(iotests.QMPTestCase):
def setUp(self):
self.vm = iotests.VM().add_drive_raw("file=blkdebug::null-co://,id=drive0,align=65536,driver=blkdebug")
self.vm.launch()
def tearDown(self):
self.vm.shutdown()
os.remove(target_img)
def test_before_write_notifier(self):
self.vm.pause_drive("drive0")
result = self.vm.qmp('drive-backup', device='drive0',
sync='full', target=target_img,
format="file", speed=1)
self.assert_qmp(result, 'return', {})
result = self.vm.qmp('block-job-pause', device="drive0")
self.assert_qmp(result, 'return', {})
# Speed is low enough that this must be an uncopied range, which will
# trigger the before write notifier
self.vm.hmp_qemu_io('drive0', 'aio_write -P 1 512512 512')
self.vm.resume_drive("drive0")
result = self.vm.qmp('block-job-resume', device="drive0")
self.assert_qmp(result, 'return', {})
event = self.cancel_and_wait()
self.assert_qmp(event, 'data/type', 'backup')
class BackupTest(iotests.QMPTestCase):
def setUp(self):
self.vm = iotests.VM()
self.test_img = img_create('test')
self.dest_img = img_create('dest')
self.dest_img2 = img_create('dest2')
self.ref_img = img_create('ref')
self.vm.add_drive(self.test_img)
self.vm.launch()
def tearDown(self):
self.vm.shutdown()
try_remove(self.test_img)
try_remove(self.dest_img)
try_remove(self.dest_img2)
try_remove(self.ref_img)
def hmp_io_writes(self, drive, patterns):
for pattern in patterns:
self.vm.hmp_qemu_io(drive, 'write -P%s %s %s' % pattern)
self.vm.hmp_qemu_io(drive, 'flush')
def qmp_backup_and_wait(self, cmd='drive-backup', serror=None,
aerror=None, **kwargs):
if not self.qmp_backup(cmd, serror, **kwargs):
return False
return self.qmp_backup_wait(kwargs['device'], aerror)
def qmp_backup(self, cmd='drive-backup',
error=None, **kwargs):
self.assertTrue('device' in kwargs)
res = self.vm.qmp(cmd, **kwargs)
if error:
self.assert_qmp(res, 'error/desc', error)
return False
self.assert_qmp(res, 'return', {})
return True
def qmp_backup_wait(self, device, error=None):
event = self.vm.event_wait(name="BLOCK_JOB_COMPLETED",
match={'data': {'device': device}})
self.assertNotEqual(event, None)
try:
failure = self.dictpath(event, 'data/error')
except AssertionError:
# Backup succeeded.
self.assert_qmp(event, 'data/offset', event['data']['len'])
return True
else:
# Failure.
self.assert_qmp(event, 'data/error', qerror)
return False
def test_overlapping_writes(self):
# Write something to back up
self.hmp_io_writes('drive0', [('42', '0M', '2M')])
# Create a reference backup
self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
sync='full', target=self.ref_img,
auto_dismiss=False)
res = self.vm.qmp('block-job-dismiss', id='drive0')
self.assert_qmp(res, 'return', {})
# Now to the test backup: We simulate the following guest
# writes:
# (1) [1M + 64k, 1M + 128k): Afterwards, everything in that
# area should be in the target image, and we must not copy
# it again (because the source image has changed now)
# (64k is the job's cluster size)
# (2) [1M, 2M): The backup job must not get overeager. It
# must copy [1M, 1M + 64k) and [1M + 128k, 2M) separately,
# but not the area in between.
self.qmp_backup(device='drive0', format=iotests.imgfmt, sync='full',
target=self.dest_img, speed=1, auto_dismiss=False)
self.hmp_io_writes('drive0', [('23', '%ik' % (1024 + 64), '64k'),
('66', '1M', '1M')])
# Let the job complete
res = self.vm.qmp('block-job-set-speed', device='drive0', speed=0)
self.assert_qmp(res, 'return', {})
self.qmp_backup_wait('drive0')
res = self.vm.qmp('block-job-dismiss', id='drive0')
self.assert_qmp(res, 'return', {})
self.assertTrue(iotests.compare_images(self.ref_img, self.dest_img),
'target image does not match reference image')
def test_dismiss_false(self):
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
sync='full', target=self.dest_img,
auto_dismiss=True)
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
def test_dismiss_true(self):
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
sync='full', target=self.dest_img,
auto_dismiss=False)
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return[0]/status', 'concluded')
res = self.vm.qmp('block-job-dismiss', id='drive0')
self.assert_qmp(res, 'return', {})
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
def test_dismiss_bad_id(self):
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
res = self.vm.qmp('block-job-dismiss', id='foobar')
self.assert_qmp(res, 'error/class', 'DeviceNotActive')
def test_dismiss_collision(self):
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
sync='full', target=self.dest_img,
auto_dismiss=False)
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return[0]/status', 'concluded')
# Leave zombie job un-dismissed, observe a failure:
res = self.qmp_backup_and_wait(serror="Job ID 'drive0' already in use",
device='drive0', format=iotests.imgfmt,
sync='full', target=self.dest_img2,
auto_dismiss=False)
self.assertEqual(res, False)
# OK, dismiss the zombie.
res = self.vm.qmp('block-job-dismiss', id='drive0')
self.assert_qmp(res, 'return', {})
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
# Ensure it's really gone.
self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
sync='full', target=self.dest_img2,
auto_dismiss=False)
def dismissal_failure(self, dismissal_opt):
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
# Give blkdebug something to chew on
self.hmp_io_writes('drive0',
(('0x9a', 0, 512),
('0x55', '8M', '352k'),
('0x78', '15872k', '1M')))
# Add destination node via blkdebug
res = self.vm.qmp('blockdev-add',
node_name='target0',
driver=iotests.imgfmt,
file={
'driver': 'blkdebug',
'image': {
'driver': 'file',
'filename': self.dest_img
},
'inject-error': [{
'event': 'write_aio',
'errno': 5,
'immediately': False,
'once': True
}],
})
self.assert_qmp(res, 'return', {})
res = self.qmp_backup(cmd='blockdev-backup',
device='drive0', target='target0',
on_target_error='stop',
sync='full',
auto_dismiss=dismissal_opt)
self.assertTrue(res)
event = self.vm.event_wait(name="BLOCK_JOB_ERROR",
match={'data': {'device': 'drive0'}})
self.assertNotEqual(event, None)
# OK, job should be wedged
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return[0]/status', 'paused')
res = self.vm.qmp('block-job-dismiss', id='drive0')
self.assert_qmp(res, 'error/desc',
"Job 'drive0' in state 'paused' cannot accept"
" command verb 'dismiss'")
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return[0]/status', 'paused')
# OK, unstick job and move forward.
res = self.vm.qmp('block-job-resume', device='drive0')
self.assert_qmp(res, 'return', {})
# And now we need to wait for it to conclude;
res = self.qmp_backup_wait(device='drive0')
self.assertTrue(res)
if not dismissal_opt:
# Job should now be languishing:
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return[0]/status', 'concluded')
res = self.vm.qmp('block-job-dismiss', id='drive0')
self.assert_qmp(res, 'return', {})
res = self.vm.qmp('query-block-jobs')
self.assert_qmp(res, 'return', [])
def test_dismiss_premature(self):
self.dismissal_failure(False)
def test_dismiss_erroneous(self):
self.dismissal_failure(True)
if __name__ == '__main__':
iotests.main(supported_fmts=['qcow2', 'qed'],
supported_protocols=['file'])