[stable-only][cve] Check VMDK create-type against an allowed list

NOTE(sbauza): Stable policy allows us to proactively merge a backport without waiting for the parent patch to be merged (exception to rule #4 in [1]. Marking [stable-only] in order to silence nova-tox-validate-backport

[1] https://docs.openstack.org/project-team-guide/stable-branches.html#appropriate-fixes

Related-Bug: #1996188
Change-Id: I5a399f1d3d702bfb76c067893e9c924904c8c360
This commit is contained in:
Dan Smith 2022-11-10 09:55:48 -08:00 committed by Sylvain Bauza
parent c9de185ea1
commit 6e8ed78470
3 changed files with 86 additions and 0 deletions

View File

@ -1015,6 +1015,15 @@ Related options:
* ``[scheduler]query_placement_for_image_type_support`` - enables
filtering computes based on supported image types, which is required
to be enabled for this to take effect.
"""),
cfg.ListOpt('vmdk_allowed_types',
default=['streamOptimized', 'monolithicSparse'],
help="""
A list of strings describing allowed VMDK "create-type" subformats
that will be allowed. This is recommended to only include
single-file-with-sparse-header variants to avoid potential host file
exposure due to processing named extents. If this list is empty, then no
form of VMDK image will be allowed.
"""),
cfg.BoolOpt('packing_host_numa_cells_allocation_strategy',
default=False,

View File

@ -16,6 +16,8 @@ import os
from unittest import mock
from oslo_concurrency import processutils
from oslo_serialization import jsonutils
from oslo_utils import imageutils
from nova.compute import utils as compute_utils
from nova import exception
@ -135,3 +137,47 @@ class QemuTestCase(test.NoDBTestCase):
'-O', 'out_format', '-f', 'in_format', 'source', 'dest')
mock_disk_op_sema.__enter__.assert_called_once()
self.assertTupleEqual(expected, mock_execute.call_args[0])
def test_convert_image_vmdk_allowed_list_checking(self):
info = {'format': 'vmdk',
'format-specific': {
'type': 'vmdk',
'data': {
'create-type': 'monolithicFlat',
}}}
# If the format is not in the allowed list, we should get an error
self.assertRaises(exception.ImageUnacceptable,
images.check_vmdk_image, 'foo',
imageutils.QemuImgInfo(jsonutils.dumps(info),
format='json'))
# With the format in the allowed list, no error
self.flags(vmdk_allowed_types=['streamOptimized', 'monolithicFlat',
'monolithicSparse'],
group='compute')
images.check_vmdk_image('foo',
imageutils.QemuImgInfo(jsonutils.dumps(info),
format='json'))
# With an empty list, allow nothing
self.flags(vmdk_allowed_types=[], group='compute')
self.assertRaises(exception.ImageUnacceptable,
images.check_vmdk_image, 'foo',
imageutils.QemuImgInfo(jsonutils.dumps(info),
format='json'))
@mock.patch.object(images, 'fetch')
@mock.patch('nova.privsep.qemu.unprivileged_qemu_img_info')
def test_fetch_checks_vmdk_rules(self, mock_info, mock_fetch):
info = {'format': 'vmdk',
'format-specific': {
'type': 'vmdk',
'data': {
'create-type': 'monolithicFlat',
}}}
mock_info.return_value = jsonutils.dumps(info)
with mock.patch('os.path.exists', return_value=True):
e = self.assertRaises(exception.ImageUnacceptable,
images.fetch_to_raw, None, 'foo', 'anypath')
self.assertIn('Invalid VMDK create-type specified', str(e))

View File

@ -110,6 +110,34 @@ def get_info(context, image_href):
return IMAGE_API.get(context, image_href)
def check_vmdk_image(image_id, data):
# Check some rules about VMDK files. Specifically we want to make
# sure that the "create-type" of the image is one that we allow.
# Some types of VMDK files can reference files outside the disk
# image and we do not want to allow those for obvious reasons.
types = CONF.compute.vmdk_allowed_types
if not len(types):
LOG.warning('Refusing to allow VMDK image as vmdk_allowed_'
'types is empty')
msg = _('Invalid VMDK create-type specified')
raise exception.ImageUnacceptable(image_id=image_id, reason=msg)
try:
create_type = data.format_specific['data']['create-type']
except KeyError:
msg = _('Unable to determine VMDK create-type')
raise exception.ImageUnacceptable(image_id=image_id, reason=msg)
if create_type not in CONF.compute.vmdk_allowed_types:
LOG.warning('Refusing to process VMDK file with create-type of %r '
'which is not in allowed set of: %s', create_type,
','.join(CONF.compute.vmdk_allowed_types))
msg = _('Invalid VMDK create-type specified')
raise exception.ImageUnacceptable(image_id=image_id, reason=msg)
def fetch_to_raw(context, image_href, path, trusted_certs=None):
path_tmp = "%s.part" % path
fetch(context, image_href, path_tmp, trusted_certs)
@ -129,6 +157,9 @@ def fetch_to_raw(context, image_href, path, trusted_certs=None):
reason=(_("fmt=%(fmt)s backed by: %(backing_file)s") %
{'fmt': fmt, 'backing_file': backing_file}))
if fmt == 'vmdk':
check_vmdk_image(image_href, data)
if fmt != "raw" and CONF.force_raw_images:
staged = "%s.converted" % path
LOG.debug("%s was %s, converting to raw", image_href, fmt)