RHSA-2009:1455 - Security Advisory

Topic

Updated kernel packages that fix one security issue and several bugs are
now available for Red Hat Enterprise Linux 5.

This update has been rated as having moderate security impact by the Red
Hat Security Response Team.

[Updated 23rd February 2010]
This update adds references to two KBase articles that includes greater
detail regarding some bug fixes that could not be fully documented in the
errata note properly.

Description

The kernel packages contain the Linux kernel, the core of any Linux
operating system.

Security fix:

• a NULL pointer dereference flaw was found in the Multiple Devices (md)

driver in the Linux kernel. If the "suspend_lo" or "suspend_hi" file on the
sysfs file system ("/sys/") is modified when the disk array is inactive, it
could lead to a local denial of service or privilege escalation. Note: By
default, only the root user can write to the files noted above.
(CVE-2009-2849, Moderate)

Bug fixes:

• a bug in nlm_lookup_host() could lead to un-reclaimed file system locks,

resulting in umount failing & NFS service relocation issues for clusters.
(BZ#517967)

• a bug in the sky2 driver prevented the phy from being reset properly on

some hardware when it hung, preventing a link from coming back up.
(BZ#517976)

• disabling MSI-X for qla2xxx also disabled MSI interrupts. (BZ#519782)
• performance issues with reads when using the qlge driver on PowerPC

systems. A system hang could also occur during reboot. (BZ#519783)

• unreliable time keeping for Red Hat Enterprise Linux virtual machines.

The KVM pvclock code is now used to detect/correct lost ticks. (BZ#520685)

• /proc/cpuinfo was missing flags for new features in supported processors,

possibly preventing the operating system & applications from getting the
best performance. (BZ#520686)

• reading/writing with a serial loopback device on a certain IBM system did

not work unless booted with "pnpacpi=off". (BZ#520905)

• mlx4_core failed to load on systems with more than 32 CPUs. (BZ#520906)
• on big-endian platforms, interfaces using the mlx4_en driver & Large

Receive Offload (LRO) did not handle VLAN traffic properly (a segmentation
fault in the VLAN stack in the kernel occurred). (BZ#520908)

• due to a lock being held for a long time, some systems may have

experienced "BUG: soft lockup" messages under heavy load. (BZ#520919)

• incorrect APIC timer calibration may have caused a system hang during

boot, as well as the system time becoming faster or slower. A warning is
now provided. (BZ#521238)

• a Fibre Channel device re-scan via 'echo "---" > /sys/class/scsi_host/

host[x]/scan' may not complete after hot adding a drive, leading to soft
lockups ("BUG: soft lockup detected"). (BZ#521239)

• the Broadcom BCM5761 network device could not to be initialized

properly; therefore, the associated interface could not obtain an IP
address via DHCP or be assigned one manually. (BZ#521241)

• when a process attempted to read from a page that had first been accessed

by writing to part of it (via write(2)), the NFS client needed to flush the
modified portion of the page out to the server, & then read the entire page
back in. This flush caused performance issues. (BZ#521244)

• a kernel panic when using bnx2x devices & LRO in a bridge. A warning is

now provided to disable LRO in these situations. (BZ#522636)

• the scsi_dh_rdac driver was updated to recognize the Sun StorageTek

Flexline 380. (BZ#523237)

• in FIPS mode, random number generators are required to not return the

first block of random data they generate, but rather save it to seed the
repetition check. This update brings the random number generator into
conformance. (BZ#523289)

• an option to disable/enable the use of the first random block is now

provided to bring ansi_cprng into compliance with FIPS-140 continuous test
requirements. (BZ#523290)

• running the SAP Linux Certification Suite in a KVM guest caused severe

SAP kernel errors, causing it to exit. (BZ#524150)

• attempting to 'online' a CPU for a KVM guest via sysfs caused a system

crash. (BZ#524151)

• when using KVM, pvclock returned bogus wallclock values. (BZ#524152)
• the clock could go backwards when using the vsyscall infrastructure.

(BZ#524527)

See References for KBase links re BZ#519782 & BZ#520906.

Users should upgrade to these updated packages, which contain backported
patches to correct these issues. Reboot the system for this update to take
effect.

Solution

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

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.4 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 5.4 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.4 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 517967 - Bug in lockd prevents a locks being freed. [rhel-5.4.z]
• BZ - 517976 - [RHEL 5] sky2 eth0: receiver hang detected [rhel-5.4.z]
• BZ - 518132 - CVE-2009-2849 kernel: md: NULL pointer deref when accessing suspend_* sysfs attributes
• BZ - 519782 - [QLogic 5.5 bug] qla2xxx - allow use of MSI when MSI-X disabled. [rhel-5.4.z]
• BZ - 519783 - [QLogic 5.5 bug] qlge - fix hangs and read perfromance [rhel-5.4.z]
• BZ - 520685 - use KVM pvclock code to detect/correct lost ticks [rhel-5.4.z]
• BZ - 520686 - bare-metal and xen: /proc/cpuinfo does not list all CPU flags presented by CPU [rhel-5.4.z]
• BZ - 520905 - Serial ports don't function on 4838-310 without pnpacpi=off boot option [rhel-5.4.z]
• BZ - 520906 - mlx4_core fails to load on systems with32 cores [rhel-5.4.z]
• BZ - 520908 - TCP traffic for VLAN interfaces fails over mlx4_en parent interface. [rhel-5.4.z]
• BZ - 520919 - BUG: soft lockup - CPU#5 stuck for 10s at .context_struct_compute_av+0x214/0x39c [rhel-5.4.z]
• BZ - 521238 - [RHEL 5] Hang on boot due to wrong APIC timer calibration [rhel-5.4.z]
• BZ - 521239 - scsi_transport_fc: fc_user_scan can loop forever, needs mutex with rport list changes [rhel-5.4.z]
• BZ - 521241 - 5.4 alpha: Broadcom 5761 NIC does not work [rhel-5.4.z]
• BZ - 521244 - Read/Write NFS I/O performance degraded by FLUSH_STABLE page flushing [rhel-5.4.z]
• BZ - 522636 - bridge: Fix LRO crash with tun (tun_chr_read()) [rhel-5.4.z]
• BZ - 523237 - Add kernel (scsi_dh_rdac) support for Sun 6540 storage arrays. [rhel-5.4.z]
• BZ - 523289 - [FIP140-2] the first n- bit block generated after power-up, initialization, or reset shall not be used [rhel-5.4.z]
• BZ - 523290 - [FIPS140-2] Provide option to disable/enable use of the first random block [rhel-5.4.z]
• BZ - 524150 - Can't override KVM clock in a KVM guest with -165 kernel to triage SAP DB create failure [rhel-5.4.z]
• BZ - 524151 - cpu1 didn't come online in a kvm i686 guest [rhel-5.4.z]
• BZ - 524152 - pvclock return bogus wallclock values [rhel-5.4.z]
• BZ - 524527 - RHEV : SAP SLCS 2.3 fails during install/import in a RHEV-H/KVM guest with PV KVM clock [rhel-5.4.z]

CVEs

• CVE-2009-2849

References

• http://www.redhat.com/security/updates/classification/#moderate
• http://kbase.redhat.com/faq/docs/DOC-24774
• http://kbase.redhat.com/faq/docs/DOC-24773