Synopsis

Important: kernel security and bug fix update

Type/Severity

Security Advisory: Important

Topic

Updated kernel packages that fix one security issue and three bugs are now
available for Red Hat Enterprise Linux 6.4 Advanced Update Support.

Red Hat Product Security has rated this update as having Important 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

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

• A use-after-free flaw was found in the way the Linux kernel's SCTP
  implementation handled authentication key reference counting during INIT
  collisions. A remote attacker could use this flaw to crash the system or,
  potentially, escalate their privileges on the system. (CVE-2015-1421,
  Important)
  

This issue was discovered by Sun Baoliang of Red Hat.

This update also fixes the following bugs:

• When ARP is disabled on an interface with an ARP entry for a neighbor
  host present in the ARP cache, letting the cached entry expire and
  attempting to communicate with that neighbor host could cause the host MAC
  address to not be resolved correctly after ARP is enabled again on the
  interface. With the following workaround, the entry is not expired and the
  described scenario works correctly:
  

1) Add the maximum number of ARP entries you expect for your configuration
to the proc/sys/net/ipv4/neigh/default/gc_thresh file.

2) Ensure that relevant IP addresses are put in the ARP cache when the
system boots, for example by executing the following two commands:

ping [IP address] -c 1
ifconfig ethX -arp

(BZ#1207350)

• Previously, the open() system call in some cases failed with an EBUSY
  error if the opened file was also being renamed at the same time. With this
  update, the kernel automatically retries open() when this failure occurs,
  and if the retry is not successful either, open() now fails with an ESTALE
  error. (BZ#1207813)
  
• Previously, a race condition occurred in the build_id_cache__add_s()
  function, which could truncate system files. A patch has been provided to
  fix this bug, and system files are no longer truncated in the
  aforementioned scenario. (BZ#1210591)
  

All kernel users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. The system must be
rebooted for this update to take effect.

Solution

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

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server - AUS 6.4 x86_64

Fixes

• BZ - 1196581 - CVE-2015-1421 kernel: net: slab corruption from use after free on INIT collisions

CVEs

• CVE-2015-1421

References

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

Red Hat Enterprise Linux Server - AUS 6.4

SRPM
kernel-2.6.32-358.61.1.el6.src.rpm	SHA-256: 7948fc5a9aaba411be8405bb07776e4143602ebf819347713d66292c28482042
x86_64
kernel-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 322ba78ea50359346211b4a9df238096fb6dcf0f2933fdc5d3aeae551bc3286e
kernel-debug-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 89edf8b69ff916ff2d8c8def694d84da0d11560c3f15b886a8582602bb5306b7
kernel-debug-debuginfo-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 21e751ec4150330574780cd1f3be4acfce2ba494f97a1af585f5756a7ad1b5eb
kernel-debug-debuginfo-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 21e751ec4150330574780cd1f3be4acfce2ba494f97a1af585f5756a7ad1b5eb
kernel-debug-devel-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: f445db26fc69d721da42838a12822260b2169b6fdcc99db11d5dcccdd0fd23a4
kernel-debuginfo-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: ef8239402d011dbe0622f56ceadb37bddc96f9bb0517998ed781b84591f6eb97
kernel-debuginfo-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: ef8239402d011dbe0622f56ceadb37bddc96f9bb0517998ed781b84591f6eb97
kernel-debuginfo-common-x86_64-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 41c91b2056974ce58d7d9ec8b37180d0835ac2c71b19ca336607939c4b3cb39a
kernel-debuginfo-common-x86_64-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 41c91b2056974ce58d7d9ec8b37180d0835ac2c71b19ca336607939c4b3cb39a
kernel-devel-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: c4357105aa1d8818e561002b077a5073fca09940fca9206a0bc20897d49a869d
kernel-doc-2.6.32-358.61.1.el6.noarch.rpm	SHA-256: a9795db7e7308caac65b2943a04d4f5d11d0a5a715dde28163636a35225a0144
kernel-firmware-2.6.32-358.61.1.el6.noarch.rpm	SHA-256: cd3679019bd5e097bcb3ceb6bdfe3a8099dd10f3fcfa733852ded1744e7c39a5
kernel-headers-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: d463f1a9b5bf1e30b9479c82f241ada4848224b811b97a1c0f05d6665ad33eb1
perf-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 23de97827bbb265b943e505aab0324173f44e660a194a0b7e84fc26eb8ab1f5a
perf-debuginfo-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 396a8c157ff0c8ddc360e158388cbbd2b36c8eba233f472220da6dc750628e39
perf-debuginfo-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 396a8c157ff0c8ddc360e158388cbbd2b36c8eba233f472220da6dc750628e39
python-perf-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: d6f1609086fa973c0df73b7cf07b46d1c3abdc49858598286d96f1c7ff42a7ad
python-perf-debuginfo-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 9f876b9a5529e3e6c5b53b7886be46e79ba23a4c7aed72817a3dbac0fc8bc99f
python-perf-debuginfo-2.6.32-358.61.1.el6.x86_64.rpm	SHA-256: 9f876b9a5529e3e6c5b53b7886be46e79ba23a4c7aed72817a3dbac0fc8bc99f