Synopsis: Important: kernel security and bug fix update
Issue Date: 2012-01-23
CVE Numbers: CVE-2012-0056
—
The kernel packages contain the Linux kernel, the core of any Linux
operating system.
This update fixes the following security issue:
* It was found that permissions were not checked properly in the Linux
kernel when handling the /proc/[pid]/mem writing functionality. A local,
unprivileged user could use this flaw to escalate their privileges. Refer
to Red Hat Knowledgebase article DOC-69129, linked to in the References,
for further information. (CVE-2012-0056, Important)
This update fixes the following bugs:
* The RHSA-2011:1849 kernel update introduced a bug in the Linux kernel
scheduler, causing a “WARNING: at kernel/sched.c:5915 thread_return”
message and a call trace to be logged. This message was harmless, and was
not due to any system malfunctions or adverse behavior. With this update,
the WARN_ON_ONCE() call in the scheduler that caused this harmless message
has been removed. (BZ#768288)
* The RHSA-2011:1530 kernel update introduced a regression in the way
the Linux kernel maps ELF headers for kernel modules into kernel memory.
If a third-party kernel module is compiled on a Red Hat Enterprise Linux
system with a kernel prior to RHSA-2011:1530, then loading that module on
a system with RHSA-2011:1530 kernel would result in corruption of one byte
in the memory reserved for the module. In some cases, this could prevent
the module from functioning correctly. (BZ#769595)
* On some SMP systems the tsc may erroneously be marked as unstable during
early system boot or while the system is under heavy load. A “Clocksource
tsc unstable” message was logged when this occurred. As a result the system
would switch to the slower access, but higher precision HPET clock.
The “tsc=reliable” kernel parameter is supposed to avoid this problem by
indicating that the system has a known good clock, however, the parameter
only affected run time checks. A fix has been put in to avoid the boot
time checks so that the TSC remains as the clock for the duration of
system runtime. (BZ#755867)
Users should upgrade to these updated packages, which contain backported
patches to correct these issues. The system must be rebooted for this
update to take effect.
—
SL6
x86_64
kernel-2.6.32-220.4.1.el6.x86_64.rpm
kernel-debug-2.6.32-220.4.1.el6.x86_64.rpm
kernel-debug-devel-2.6.32-220.4.1.el6.x86_64.rpm
kernel-devel-2.6.32-220.4.1.el6.x86_64.rpm
kernel-headers-2.6.32-220.4.1.el6.x86_64.rpm
perf-2.6.32-220.4.1.el6.x86_64.rpm
python-perf-2.6.32-220.4.1.el6.x86_64.rpm
i386
kernel-2.6.32-220.4.1.el6.i686.rpm
kernel-debug-2.6.32-220.4.1.el6.i686.rpm
kernel-debug-devel-2.6.32-220.4.1.el6.i686.rpm
kernel-devel-2.6.32-220.4.1.el6.i686.rpm
kernel-headers-2.6.32-220.4.1.el6.i686.rpm
perf-2.6.32-220.4.1.el6.i686.rpm
python-perf-2.6.32-220.4.1.el6.i686.rpm
noarch
kernel-doc-2.6.32-220.4.1.el6.noarch.rpm
kernel-firmware-2.6.32-220.4.1.el6.noarch.rpm
– Scientific Linux Development Team
