openstack
/
neutron
Code Issues Proposed changes

Add locks for setting iptables rules in l3 and metadata agents 

Router_info class and metadata agent's driver are using same
instance of the iptables manager class and it could happend that
sometimes e.g. nat rule which packets send to 169.254.169.254:80
redirects to the port 9697 so haproxy can process them, can be missed as
they will be overwritten by the Router_info class manipulating other
rules in the same 'nat' rules list.

This patch fixed that by adding lock for methods which are changing
rules in iptables_manager's nat table in both router_info and
the metadata agent's driver.

Closes-Bug: #1920778
Change-Id: Ic3a324c0e608c7afc4b15dbc8becd33b75ee78f6
(cherry picked from commit af3c1b8442)
This commit is contained in:
Slawek Kaplonski 2021-03-24 12:02:14 +01:00
parent 5858f6c502
commit 51163ffa46
1 changed files with 22 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
neutron/agent/metadata/driver.py
View File

@ -33,6 +33,7 @@ from neutron.agent.l3 import namespaces
from neutron.agent.linux import external_process
from neutron.agent.linux import ip_lib
from neutron.agent.linux import utils as linux_utils
from neutron.common import coordination
from neutron.common import utils as common_utils
@ -307,26 +308,10 @@ class MetadataDriver(object):
def after_router_added(resource, event, l3_agent, **kwargs):
router = kwargs['router']
proxy = l3_agent.metadata_driver
ipv6_enabled = netutils.is_ipv6_enabled()
for c, r in proxy.metadata_filter_rules(proxy.metadata_port,
proxy.metadata_access_mark):
router.iptables_manager.ipv4['filter'].add_rule(c, r)
if ipv6_enabled:
for c, r in proxy.metadata_filter_rules(proxy.metadata_port,
proxy.metadata_access_mark):
router.iptables_manager.ipv6['filter'].add_rule(c, r)
for c, r in proxy.metadata_nat_rules(proxy.metadata_port):
router.iptables_manager.ipv4['nat'].add_rule(c, r)
if ipv6_enabled:
for c, r in proxy.metadata_nat_rules(
proxy.metadata_port,
metadata_address=(constants.METADATA_V6_IP + '/128')):
router.iptables_manager.ipv6['nat'].add_rule(c, r)
router.iptables_manager.apply()
apply_metadata_nat_rules(router, proxy)
if not isinstance(router, ha_router.HaRouter):
spawn_kwargs = {}
if ipv6_enabled:
if netutils.is_ipv6_enabled():
spawn_kwargs['bind_address'] = '::'
proxy.spawn_monitored_metadata_proxy(
l3_agent.process_monitor,
@ -362,3 +347,22 @@ def before_router_removed(resource, event, l3_agent, payload=None):
router.router['id'],
l3_agent.conf,
router.ns_name)
@coordination.synchronized('router-lock-ns-{router.ns_name}')
def apply_metadata_nat_rules(router, proxy):
for c, r in proxy.metadata_filter_rules(proxy.metadata_port,
proxy.metadata_access_mark):
router.iptables_manager.ipv4['filter'].add_rule(c, r)
if netutils.is_ipv6_enabled():
for c, r in proxy.metadata_filter_rules(proxy.metadata_port,
proxy.metadata_access_mark):
router.iptables_manager.ipv6['filter'].add_rule(c, r)
for c, r in proxy.metadata_nat_rules(proxy.metadata_port):
router.iptables_manager.ipv4['nat'].add_rule(c, r)
if netutils.is_ipv6_enabled():
for c, r in proxy.metadata_nat_rules(
proxy.metadata_port,
metadata_address=(constants.METADATA_V6_IP + '/128')):
router.iptables_manager.ipv6['nat'].add_rule(c, r)
router.iptables_manager.apply()