tripleo-heat-templates/docker_config_scripts/tests/test_nova_statedir_ownership.py
Oliver Walsh 58624abf5f Improve nova statedir ownership logic
The nova_compute container kolla config is currently set to recursively change
the ownership of /var/lib/nova to nova:nova on startup.

This is necessary when upgrading from an non-container deployment to a
containerized deployment as the nova uids are not consistent across the host
and container image.

If the nova instancedir is an NFS mount then open filehandles are
broken and every VM using that NFS export fails with I/O errors.

This change re-implements the nova statedir ownership logic to target only the
files/directories controlled by nova.

Requires dist-git change: https://review.rdoproject.org/r/14734

Change-Id: I57d421feb6356d28002e77fb9bfa50a397758cbf
Closes-bug: 1778465
2018-07-09 17:07:30 +01:00

261 lines
9.5 KiB
Python

#
# Copyright 2018 Red Hat Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import contextlib
import mock
import six
import stat
from oslotest import base
from docker_config_scripts.nova_statedir_ownership import \
NovaStatedirOwnershipManager
from docker_config_scripts.nova_statedir_ownership import PathManager
# Real chown would require root, so in order to test this we need to fake
# all of the methods that interact with the filesystem
current_uid = 100
current_gid = 100
class FakeStatInfo(object):
def __init__(self, st_mode, st_uid, st_gid):
self.st_mode = st_mode
self.st_uid = st_uid
self.st_gid = st_gid
def get_ids(self):
return (self.st_uid, self.st_gid)
def generate_testtree1(nova_uid, nova_gid):
return {
'/var/lib/nova':
FakeStatInfo(st_mode=stat.S_IFDIR,
st_uid=nova_uid,
st_gid=nova_gid),
'/var/lib/nova/instances':
FakeStatInfo(st_mode=stat.S_IFDIR,
st_uid=nova_uid,
st_gid=nova_gid),
'/var/lib/nova/instances/foo':
FakeStatInfo(st_mode=stat.S_IFDIR,
st_uid=nova_uid,
st_gid=nova_gid),
'/var/lib/nova/instances/foo/bar':
FakeStatInfo(st_mode=stat.S_IFREG,
st_uid=0,
st_gid=0),
'/var/lib/nova/instances/foo/baz':
FakeStatInfo(st_mode=stat.S_IFREG,
st_uid=nova_uid,
st_gid=nova_gid),
'/var/lib/nova/instances/foo/abc':
FakeStatInfo(st_mode=stat.S_IFREG,
st_uid=0,
st_gid=nova_gid),
'/var/lib/nova/instances/foo/def':
FakeStatInfo(st_mode=stat.S_IFREG,
st_uid=nova_uid,
st_gid=0),
}
def generate_testtree2(marker_uid, marker_gid, *args, **kwargs):
tree = generate_testtree1(*args, **kwargs)
tree.update({
'/var/lib/nova/upgrade_marker':
FakeStatInfo(st_mode=stat.S_IFREG,
st_uid=marker_uid,
st_gid=marker_gid)
})
return tree
def generate_fake_stat(testtree):
def fake_stat(path):
return testtree.get(path)
return fake_stat
def generate_fake_chown(testtree):
def fake_chown(path, uid, gid):
if uid != -1:
testtree[path].st_uid = uid
if gid != -1:
testtree[path].st_gid = gid
return fake_chown
def generate_fake_exists(testtree):
def fake_exists(path):
return path in testtree
return fake_exists
def generate_fake_listdir(testtree):
def fake_listdir(path):
path_parts = path.split('/')
for entry in testtree:
entry_parts = entry.split('/')
if (entry_parts[:len(path_parts)] == path_parts and
len(entry_parts) == len(path_parts) + 1):
yield entry
return fake_listdir
def generate_fake_unlink(testtree):
def fake_unlink(path):
del testtree[path]
return fake_unlink
@contextlib.contextmanager
def fake_testtree(testtree):
fake_stat = generate_fake_stat(testtree)
fake_chown = generate_fake_chown(testtree)
fake_exists = generate_fake_exists(testtree)
fake_listdir = generate_fake_listdir(testtree)
fake_unlink = generate_fake_unlink(testtree)
with mock.patch('os.chown',
side_effect=fake_chown) as fake_chown:
with mock.patch('os.path.exists',
side_effect=fake_exists) as fake_exists:
with mock.patch('os.listdir',
side_effect=fake_listdir) as fake_listdir:
with mock.patch('pwd.getpwnam',
return_value=(0, 0, current_uid, current_gid)):
with mock.patch('os.stat',
side_effect=fake_stat) as fake_stat:
with mock.patch(
'os.unlink',
side_effect=fake_unlink
) as fake_unlink:
yield (fake_chown,
fake_exists,
fake_listdir,
fake_stat,
fake_unlink)
def assert_ids(testtree, path, uid, gid):
statinfo = testtree[path]
assert (uid, gid) == (statinfo.st_uid, statinfo.st_gid), \
"{}: expected {}:{} actual {}:{}".format(
path, uid, gid, statinfo.st_uid, statinfo.st_gid
)
class PathManagerCase(base.BaseTestCase):
def test_file(self):
testtree = generate_testtree1(current_uid, current_gid)
with fake_testtree(testtree):
pathinfo = PathManager('/var/lib/nova/instances/foo/baz')
self.assertTrue(pathinfo.has_owner(current_uid, current_gid))
self.assertTrue(pathinfo.has_either(current_uid, 0))
self.assertTrue(pathinfo.has_either(0, current_gid))
self.assertFalse(pathinfo.is_dir)
self.assertEqual(str(pathinfo), 'uid: {} gid: {} path: {}'.format(
current_uid, current_gid, '/var/lib/nova/instances/foo/baz'
))
def test_dir(self):
testtree = generate_testtree1(current_uid, current_gid)
with fake_testtree(testtree):
pathinfo = PathManager('/var/lib/nova')
self.assertTrue(pathinfo.has_owner(current_uid, current_gid))
self.assertTrue(pathinfo.has_either(current_uid, 0))
self.assertTrue(pathinfo.has_either(0, current_gid))
self.assertTrue(pathinfo.is_dir)
self.assertEqual(str(pathinfo), 'uid: {} gid: {} path: {}'.format(
current_uid, current_gid, '/var/lib/nova/'
))
def test_chown(self):
testtree = generate_testtree1(current_uid, current_gid)
with fake_testtree(testtree):
pathinfo = PathManager('/var/lib/nova/instances/foo/baz')
self.assertTrue(pathinfo.has_owner(current_uid, current_gid))
pathinfo.chown(current_uid+1, current_gid)
assert_ids(testtree, pathinfo.path, current_uid+1, current_gid)
def test_chgrp(self):
testtree = generate_testtree1(current_uid, current_gid)
with fake_testtree(testtree):
pathinfo = PathManager('/var/lib/nova/instances/foo/baz')
self.assertTrue(pathinfo.has_owner(current_uid, current_gid))
pathinfo.chown(current_uid, current_gid+1)
assert_ids(testtree, pathinfo.path, current_uid, current_gid+1)
def test_chown_chgrp(self):
testtree = generate_testtree1(current_uid, current_gid)
with fake_testtree(testtree):
pathinfo = PathManager('/var/lib/nova/instances/foo/baz')
self.assertTrue(pathinfo.has_owner(current_uid, current_gid))
pathinfo.chown(current_uid+1, current_gid+1)
assert_ids(testtree, pathinfo.path, current_uid+1, current_gid+1)
class NovaStatedirOwnershipManagerTestCase(base.BaseTestCase):
def test_no_upgrade_marker(self):
testtree = generate_testtree1(current_uid, current_gid)
with fake_testtree(testtree) as (fake_chown, _, _, _, _):
NovaStatedirOwnershipManager('/var/lib/nova').run()
fake_chown.assert_not_called()
def test_upgrade_marker_no_id_change(self):
testtree = generate_testtree2(current_uid,
current_gid,
current_uid,
current_gid)
with fake_testtree(testtree) as (fake_chown, _, _, _, fake_unlink):
NovaStatedirOwnershipManager('/var/lib/nova').run()
fake_chown.assert_not_called()
fake_unlink.assert_called_with('/var/lib/nova/upgrade_marker')
def test_upgrade_marker_id_change(self):
other_uid = current_uid + 1
other_gid = current_gid + 1
testtree = generate_testtree2(other_uid,
other_gid,
other_uid,
other_gid)
# Determine which paths should change uid/gid
expected_changes = {}
for k, v in six.iteritems(testtree):
if k == '/var/lib/nova/upgrade_marker':
# Ignore the marker, it should be deleted
continue
if v.st_uid == other_uid or v.st_gid == other_gid:
expected_changes[k] = (
current_uid if v.st_uid == other_uid else v.st_uid,
current_gid if v.st_gid == other_gid else v.st_gid
)
with fake_testtree(testtree) as (_, _, _, _, fake_unlink):
NovaStatedirOwnershipManager('/var/lib/nova').run()
for fn, expected in six.iteritems(expected_changes):
assert_ids(testtree, fn, expected[0], expected[1])
fake_unlink.assert_called_with('/var/lib/nova/upgrade_marker')