RHSA-2015:1680 - Security Advisory

Topic

Updated openstack-neutron packages that fix one security issue are now
available for Red Hat Enterprise Linux OpenStack Platform 6.0

Red Hat Product Security has rated this update as having a Moderate security
impact. A Common Vulnerability Scoring System (CVSS) base score, which
gives a detailed severity rating, is available from the CVE link in the
References section.

Description

OpenStack Networking (Neutron) is a pluggable, scalable, and API-driven
system that provisions networking services to virtual machines. Its main
function is to manage connectivity to and from virtual machines.

A Denial of Service flaw was found in the L2 agent when using the IPTables
firewall driver. By submitting an address pair that will be rejected as
invalid by the ipset tool, an attacker may cause the agent to crash.
(CVE-2015-3221)

Red Hat would like to thank the OpenStack upstream for reporting this
issue. Upstream acknowledges Darragh O'Reilly (HP) as the original reporter.

Additionally, the packages address the following issues:

• Neutron failed to load multiple configuration files. The Puppet recipe

hard-coded the --config-file parameter to a set list of configuration files
and additional files were not loaded, even if specified. This fix creates a
new Neutron configuration directory, /etc/neutron/conf.d, and any .conf
files in that directory are loaded by Puppet and applied to all services.
(BZ#1188480)

• When configuring load balancer as a service, the Neutron configuration

used no group as the default system user group. This group does not exist
in the default Red Hat Enterprise Linux 7 configuration, which caused the
virtual IP address creation to fail with the error "cannot find group id
for 'nogroup'." (BZ#1208002)

• Log rotation was set to one week for Neutron, but that could allow the

log file to grow to be very large before rotating. The default log rotation
policy has been updated to include a size limit of 10MB as well as a time
limit to rotate daily. (BZ#1212442)

• Previously, dnsmasq did not save lease information in persistent storage.

When it was restarted, the lease information was lost. This behavior
resulted from removing the '--dhcp-script' option as part of fixing
BZ#1202392. As a result, instances were stuck in the network boot process
for a long period of time. In addition, NACK messages were noted in the
dnsmasq log. This update removes the authoritative option, so that NAKs are
not sent in response to DHCPREQUESTs to other servers. This change is
expected to prevent dnsmasq from NAKing clients renewing leases issued
before it was restarted/rescheduled. DHCPNAK messages should no longer be
found in the log files. (BZ#1227635)

• Conflict tags were included in the python-neutron package spec that

resulted in Neutron unnecessarily blocking the python-oslo-db package.
These conflicts have been removed from the spec, so the python-oslo-db
package can be successfully installed. (BZ#1250056)

All openstack-neutron users are advised to upgrade to these updated
packages, which contain backported patches to correct these issues.

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the
Red Hat Network to apply this update are available at
https://access.redhat.com/articles/11258

Affected Products

• Red Hat OpenStack 6.0 x86_64

Fixes

• BZ - 1208002 - LBASS VIP creation fails because system group "nogroup" doesn't exist
• BZ - 1227635 - DHCPNAK after neutron-dhcp-agent restart
• BZ - 1232284 - CVE-2015-3221 openstack-neutron: L2 agent DoS through incorrect allowed address pairs
• BZ - 1250056 - neutron unnecessarily blocks python-oslo-db >= 1.1.0

CVEs

• CVE-2015-3221

References

• https://access.redhat.com/security/updates/classification/#moderate