RHBA-2011:0729 - Bug Fix Advisory

Topic

Updated net-snmp packages that resolve several issues are now available for Red
Hat Enterprise Linux 6.

Description

SNMP (Simple Network Management Protocol) is a protocol used for network
management. The NET-SNMP project includes various SNMP tools: an extensible
agent, an SNMP library, tools for requesting or setting information from
SNMP agents, tools for generating and handling SNMP traps and a version of
the netstat command which uses SNMP. This package contains the snmpd and
snmptrapd daemons, documentation, etc.

These updated net-snmp packages provide fixes for the following bugs:

• The IP-MIB::ipAddressTable did not support SNMP SET operation, which

enables adding or deleting rows in the IP address table. As a result IPv4
or IPv6 addresses on interfaces could neither be created or removed. The
updated packages enhance IP-MIB::ipAddressTable with these functions as
per RFC 4293 mandates. (BZ#616336, BZ#616764).

• Under certain conditions, and especially on networks with high traffic,

snmpd wrote a lot of "c64 32 bit check failed" and
"netsnmp_assert 1 == new_val->high failed" messages to the system log.
Although these messages are harmless and not indicative of a serious error,
they could potentially fill the system log quickly. This update suppresses
these spurious messages in favour of more meaningful and specific error
messages, which are written to the system log only once. (BZ#621664).

• The SNMP daemon did not properly handle netlink sockets when forking to

background and becoming a daemon. It could therefore not process incoming
notifications from kernel regarding changes in IP-MIB::ipAddressPrefixTable.
The updated package fixes the socket processing to ensure SNMP deamon
handles incoming kernel notifications and updates ipAddressPrefixTable in
runtime. (BZ#625262).

• The SNMP daemon did not detect and notify newly added or activated

interfaces in IPV6-MIB::627564ipv6IfTable. The updated package
properly refreshes the table when new interface appears. (BZ#627564).

• The implementation of BRIDGE-MIB was enhanced with Virtual LANs

(RFC 4363). (BZ#630157).

• The snmpwalk utility did not perform correct OID comparison and printed

additional objects when walking through an OID subtree. The updated
package fixed the OID comparison so that snmpwalk prints only the objects
from requested subtree. (BZ#636890).

• The SNMP daemon 'snmpd', returned incorrect value of either "0.1" or

1.3" for sysObjectID. This update fixes the value of this OID so it
returns the correct value, "1.3.6.1.4.1.8072.3.2.10".(BZ#641113)

• The Net-SNMP source RPM package failed to compile on machine incase of a

disabled IPv6 networking stack since the built-in test suite requires a
working IPv6. The updated package correctly recovers from a disabled IPv6
stack and compiles successfully. (BZ#657835).

• The problem was that in some cases SNMP daemon 'snmpd', wrongly retyped

pointers to integer data when processing SMUX packets resulting in a
freeze. The pointer operations were fixed in the updated package to avoid
snmpd freeze while processing SMUX packets. (BZ#665053).

• The snmpd daemon handled incorrectly internal list of SMUX registrations,

which could result in snmpd crash when processing SMUX messages. The
updated package fixes the list handling and does not crash when processing
SMUX messages. (BZ#672595).

• The snmpd daemon did not properly initialize it's structures for

IP-MIB::ipSystemStatsTable and IP-MIB::ipIfStatsTable properly. It returned
this error message "looks like a 64bit wrap, but prev!=new" to log if a
counter in these tables got larger than 32bits. The updated packages fixes
initialization of the tables and ensures that the aforementioned message
should not appear in snmpd log. (BZ#674757).

All users of net-snmp are advised to upgrade to these updated packages,
which resolve 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/kb/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension (for IBM z Systems) 6 s390x

Fixes

• BZ - 616336 - [TAHI] ipAddressTable doesn't support snmpset operation.
• BZ - 616764 - snmpset cannot create new row in ipAddressTable
• BZ - 625262 - [TAHI] snmpd returns "false" value of ipAddressPrefixAutonomousFlag for host
• BZ - 627564 - net-snmp does not report newly activated IPV6 interfaces
• BZ - 641113 - snmpd always returns an incorrect sysObjectID of ".1.3" or ".0.1"
• BZ - 657835 - IPv6 tests fail instead of being skipped
• BZ - 672595 - Segfault when starting snmpd

CVEs

(none)

References

(none)