Security Advisory Important: kernel-rt security and bug fix update

Advisory: RHSA-2012:0333-1
Type: Security Advisory
Severity: Important
Issued on: 2012-02-23
Last updated on: 2012-02-23
Affected Products: Red Hat Enterprise MRG v2 for Red Hat Enterprise Linux (version 6)
CVEs ( CVE-2011-2918


Updated kernel-rt packages that fix multiple security issues and various
bugs are now available for Red Hat Enterprise MRG 2.1.

The Red Hat Security Response Team has rated this update as having
important security impact. Common Vulnerability Scoring System (CVSS) base
scores, which give detailed severity ratings, are available for each
vulnerability from the CVE links in the References section.

These packages contain the Linux kernel.

Security fixes:

* SG_IO ioctl SCSI requests on partitions or LVM volumes could be passed to
the underlying block device, allowing a privileged user to bypass
restrictions and gain read and write access (and be able to issue other
SCSI commands) to the entire block device. (CVE-2011-4127, Important)

* A local, unprivileged user could use an integer overflow flaw in
drm_mode_dirtyfb_ioctl() to cause a denial of service or escalate their
privileges. (CVE-2012-0044, Important)

* A local, unprivileged user could use a flaw in the Performance Events
implementation to cause a denial of service. (CVE-2011-2918, Moderate)

* A local, unprivileged user could use flaws in the XFS file system
implementation to cause a denial of service or escalate their privileges by
mounting a specially-crafted disk. (CVE-2011-4077, CVE-2012-0038, Moderate)

* A local, unprivileged user could use a flaw in the Out of Memory (OOM)
killer to monopolize memory, have their process skipped by the OOM killer,
or cause other tasks to be terminated. (CVE-2011-4097, Moderate)

* A local, unprivileged user could use a flaw in the key management
facility to cause a denial of service. (CVE-2011-4110, Moderate)

* A malicious Network File System version 4 (NFSv4) server could return a
crafted reply to a GETACL request, causing a denial of service on the
client. (CVE-2011-4131, Moderate)

* A local attacker could use a flaw in the Journaling Block Device (JBD) to
crash the system by mounting a specially-crafted ext3 or ext4 disk.
(CVE-2011-4132, Moderate)

* A flaw in igmp_heard_query() could allow an attacker, who is able to send
certain IGMP (Internet Group Management Protocol) packets to a target
system, to cause a denial of service. (CVE-2012-0207, Moderate)

* If lock contention during signal sending occurred when in a software
interrupt handler that is using the per-CPU debug stack, the task could be
scheduled out on the realtime kernel, possibly leading to debug stack
corruption. A local, unprivileged user could use this flaw to cause a
denial of service. (CVE-2012-0810, Moderate)

Red Hat would like to thank Chen Haogang for reporting CVE-2012-0044;
Wang Xi for reporting CVE-2012-0038; Shubham Goyal for reporting
CVE-2011-4097; Andy Adamson for reporting CVE-2011-4131; and Simon McVittie
for reporting CVE-2012-0207.

Bug fixes:

* When a sleeping task, waiting on a futex (fast userspace mutex), tried to
get the spin_lock(hb->lock) RT-mutex, if the owner of the futex released
the lock, the sleeping task was put on a futex proxy lock. Consequently,
the sleeping task was blocked on two locks and eventually terminated in the
BUG_ON() function. With this update, the WAKEUP_INPROGRESS pseudo-lock has
been added to be used as a proxy lock. This pseudo-lock tells the sleeping
task that it is being woken up so that the task no longer tries to get the
second lock. Now, the futex code works as expected and sleeping tasks no
longer crash in the described scenario. (BZ#784733)

* When the CONFIG_CRYPTO_FIPS configuration option was disabled, some
services such as sshd and ipsec, while working properly, returned warning
messages regarding this missing option during start up. With this update,
CONFIG_CRYPTO_FIPS has been enabled and no warning messages are now
returned in the described scenario. (BZ#786145)

* Previously, when a read operation on a loop device failed, the data
successfully read from the device was not cleared and could eventually
leak. This bug has been fixed and all data are now properly cleared in the
described scenario. (BZ#761420)

* Due to an assembler-sourced object, the perf utility (from the perf-rt
package) for AMD64 and Intel 64 architectures contained an executable
stack. This update adds the ".note.GNU-stack" section definition to the
bench/mem-memcpy-x86-64-asm.S component of perf, with all flags disabled,
and perf no longer contains an executable stack, thus fixing this bug.


Users should upgrade to these updated packages, which correct these
issues. The system must be rebooted for this update to take effect.

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

To install kernel packages manually, use "rpm -ivh [package]". Do not
use "rpm -Uvh" as that will remove the running kernel binaries from
your system. You may use "rpm -e" to remove old kernels after
determining that the new kernel functions properly on your system.

Updated packages

Red Hat Enterprise MRG v2 for Red Hat Enterprise Linux (version 6)

File outdated by:  RHSA-2017:1647
    MD5: 9a7ed06dd3031d7154294ae669f783cb
SHA-256: 9ca701403fabdee895989127dc891f87f0f3a677b53b23ccc68c75466a81db35
File outdated by:  RHSA-2017:1647
    MD5: 0492b05d922d1b548da61b338b6517a0
SHA-256: 25bd215b3be24258448742cadafacb9fa436be30efe20ca17c7afb1c055e32f7
File outdated by:  RHSA-2017:1647
    MD5: df9db6bdbf065149ddeaf0ce5ab65c29
SHA-256: 419d565e358c8c4aa14e4e5b544e1bf188fd6f35c7c00b288cea099cef4077f1
File outdated by:  RHSA-2017:1647
    MD5: 79191942bc48be45c816d58978f0276d
SHA-256: fe258c6926511531be5bc3193910294afb3c3819446871e09feaa013eef3be78
File outdated by:  RHSA-2017:1647
    MD5: 0f633ce5895407c683ed460907096a93
SHA-256: 035bc1086876fe8991ed3681cd30fab969102f458ceb48c714ee23d3177d805d
File outdated by:  RHSA-2017:1647
    MD5: 72fd74c951bea5535d996b55b0d2a1ba
SHA-256: 979743cdf91dd5352b4c8a8c6cadbf42d9ff6f80537c517717d5b8aef08dd60c
File outdated by:  RHSA-2017:1647
    MD5: 7d9bd055045b5516094c3a660c605cfc
SHA-256: 9797e3b5972541452f5c8a26202911d4f56ab637721fefbb59124cc7ec159425
File outdated by:  RHSA-2017:1647
    MD5: 2133ead3b852dd3e3405b06516376cc7
SHA-256: 7ed59f0a5f5983c7fcb83fe28bca182997184ce36cc5470c5cc403618881208e
File outdated by:  RHSA-2017:1647
    MD5: 7424826c9eb068d02876d0b3ed3c580a
SHA-256: 7db6f403f8a7fe41eca9acafd1992e5f01344b7edb1f1b1e66e21000a5457fd6
File outdated by:  RHSA-2017:1647
    MD5: b5755103825b4e090db172756ffd50d5
SHA-256: 8e78d92a99e961a8fc62638e34897dcef2adb191be0b548a5399f8520f4b1939
File outdated by:  RHSA-2017:1647
    MD5: ef70e24bad7def427ed0fdb36fd04111
SHA-256: ac4652d68653db62e09ee89ad8a42001b945c99cf36e01fb4d530868e0b0baba
File outdated by:  RHSA-2017:1647
    MD5: df062da900c895809ceee9c0fa6c6395
SHA-256: 705f4e37219ff9bf2cd7de775ae57ff65dd5f46fd2d47e380cdc79d41a83b063
File outdated by:  RHSA-2017:1647
    MD5: 2c49ed38712240d2191fee7d6ad50ed3
SHA-256: 9a4d15ba26ed0bd49c21c48df1768ba80b059510f20247fb38fd80955b9597ce
File outdated by:  RHSA-2017:1647
    MD5: 9b8ebc184f7dc7f1d1c4dd06dde5c330
SHA-256: a3db1ac8bdcac4c9fb8a48c2b25f3474e930f055d428affa19cd2a17de5b6c81
File outdated by:  RHSA-2017:1647
    MD5: f7db4f2d2be956786df17f179ebb3b2e
SHA-256: 0753eb13a70a76a09cd6bcb9d28100b3a779121d8ce03b85f499cf9fad06b545
File outdated by:  RHSA-2017:1647
    MD5: dd785ecf7788d75768d60bb8f9d061b6
SHA-256: 5eef289ee41e5c00de401456e1f58861eb19667c5a7e33171757b6770012f981
(The unlinked packages above are only available from the Red Hat Network)

Bugs fixed (see bugzilla for more information)

730706 - CVE-2011-2918 kernel: perf: Fix software event overflow
747106 - CVE-2011-4131 kernel: nfs4_getfacl decoding kernel oops
749156 - CVE-2011-4077 kernel: xfs: potential buffer overflow in xfs_readlink()
750399 - CVE-2011-4097 kernel: oom_badness() integer overflow
751297 - CVE-2011-4110 kernel: keys: NULL pointer deref in the user-defined key type
752375 - CVE-2011-4127 kernel: possible privilege escalation via SG_IO ioctl
753341 - CVE-2011-4132 kernel: jbd/jbd2: invalid value of first log block leads to oops
772867 - CVE-2012-0207 kernel: igmp: Avoid zero delay when receiving odd mixture of IGMP queries
772894 - CVE-2012-0044 kernel: drm: integer overflow in drm_mode_dirtyfb_ioctl()
773280 - CVE-2012-0038 kernel: xfs heap overflow
784733 - BUG at kernel/rtmutex.c:472 MRG 2.1 3.0.9-rt26.45.el6rt.x86_64 kernel
786145 - missing /proc/sys/crypto/fips_enabled in 3.0.9 causes openssh errors
794557 - CVE-2012-0810 kernel-rt: stack corruption when task gets scheduled out using the debug stack


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