Important CentOS kernel Security Update


kernel-3.10.0-327.3.1.el7.src.rpm, kernel-3.10.0-327.3.1.el7.x86_64.rpm, kernel-abi-whitelists-3.10.0-327.3.1.el7.noarch.rpm, kernel-debug-3.10.0-327.3.1.el7.x86_64.rpm, kernel-debug-devel-3.10.0-327.3.1.el7.x86_64.rpm, kernel-devel-3.10.0-327.3.1.el7.x86_64.rpm, kernel-doc-3.10.0-327.3.1.el7.noarch.rpm, kernel-headers-3.10.0-327.3.1.el7.x86_64.rpm, kernel-tools-3.10.0-327.3.1.el7.x86_64.rpm, kernel-tools-libs-3.10.0-327.3.1.el7.x86_64.rpm, kernel-tools-libs-devel-3.10.0-327.3.1.el7.x86_64.rpm, perf-3.10.0-327.3.1.el7.x86_64.rpm, python-perf-3.10.0-327.3.1.el7.x86_64.rpm,
2018-01-18 11:11
2017-07-27 19:10
2017-04-01 19:09
2017-01-05 20:13


Updated kernel packages that fix two security issues, several bugs, and add
one enhancement are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security 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.

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

* It was found that the x86 ISA (Instruction Set Architecture) is prone to
a denial of service attack inside a virtualized environment in the form of
an infinite loop in the microcode due to the way (sequential) delivering of
benign exceptions such as #AC (alignment check exception) and #DB (debug
exception) is handled. A privileged user inside a guest could use these
flaws to create denial of service conditions on the host kernel.
(CVE-2015-5307, CVE-2015-8104, Important)

Red Hat would like to thank Ben Serebrin of Google Inc. for reporting the
CVE-2015-5307 issue.

This update also fixes the following bugs:

* On Intel Xeon v5 platforms, the processor frequency was always tied to
the highest possible frequency. Switching p-states on these client
platforms failed. This update sets the idle frequency, busy frequency, and
processor frequency values by determining the range and adjusting the
minimal and maximal percent limit values. Now, switching p-states on the
aforementioned client platforms proceeds successfully. (BZ#1273926)

* Due to a validation error of in-kernel memory-mapped I/O (MMIO) tracing,
a VM became previously unresponsive when connected to Red Hat Enterprise
Virtualization Hypervisor. The provided patch fixes this bug by dropping
the check in MMIO handler, and a VM continues running as expected.

* Due to retry-able command errors, the NVMe driver previously leaked I/O
descriptors and DMA mappings. As a consequence, the kernel could become
unresponsive during the hot-unplug operation if a driver was removed.
This update fixes the driver memory leak bug on command retries, and the
kernel no longer hangs in this situation. (BZ#1279792)

* The hybrid_dma_data() function was not initialized before use, which
caused an invalid memory access when hot-plugging a PCI card. As a
consequence, a kernel oops occurred. The provided patch makes sure
hybrid_dma_data() is initialized before use, and the kernel oops no longer
occurs in this situation. (BZ#1279793)

* When running PowerPC (PPC) KVM guests and the host was experiencing a lot
of page faults, for example because it was running low on memory, the host
sometimes triggered an incorrect kind of interrupt in the guest: a data
storage exception instead of a data segment exception. This caused a kernel
panic of the PPC KVM guest. With this update, the host kernel synthesizes a
segment fault if the corresponding Segment Lookaside Buffer (SLB) lookup
fails, which prevents the kernel panic from occurring. (BZ#1281423)

* The kernel accessed an incorrect area of the khugepaged process causing
Logical Partitioning (LPAR) to become unresponsive, and an oops occurred in
medlp5. The backported upstream patch prevents an LPAR hang, and the oops
no longer occurs. (BZ#1281424)

* When the sctp module was loaded and a route to an association endpoint
was removed after receiving an Out-of-The-Blue (OOTB) chunk but before
incrementing the "dropped because of missing route" SNMP statistic, a Null
Pointer Dereference kernel panic previously occurred. This update fixes the
race condition between OOTB response and route removal. (BZ#1281426)

* The cpuscaling test of the certification test suite previously failed due
to a rounding bug in the intel-pstate driver. This bug has been fixed and
the cpuscaling test now passes. (BZ#1281491)

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.
Please see

Am I vulnerable?

The constraints below list the versions that this vulnerability is patched in, and versions that are unaffected. If a patch is ready but unrealeased, then it is pending.

Or, you can just let us figure it out for you! Appcanary continously monitor your installed packages, and tell you if any of them are vulnerable.

Sign up for monitoring

Affected package information

Release Package Patched in
7 kernel kernel-3.10.0-327.3.1.el7.src.rpm
kernel kernel-3.10.0-327.3.1.el7.x86_64.rpm
kernel-abi-whitelists kernel-abi-whitelists-3.10.0-327.3.1.el7.noarch.rpm
kernel-debug kernel-debug-3.10.0-327.3.1.el7.x86_64.rpm
kernel-debug-devel kernel-debug-devel-3.10.0-327.3.1.el7.x86_64.rpm
kernel-devel kernel-devel-3.10.0-327.3.1.el7.x86_64.rpm
kernel-doc kernel-doc-3.10.0-327.3.1.el7.noarch.rpm
kernel-headers kernel-headers-3.10.0-327.3.1.el7.x86_64.rpm
kernel-tools kernel-tools-3.10.0-327.3.1.el7.x86_64.rpm
kernel-tools-libs kernel-tools-libs-3.10.0-327.3.1.el7.x86_64.rpm
kernel-tools-libs-devel kernel-tools-libs-devel-3.10.0-327.3.1.el7.x86_64.rpm
perf perf-3.10.0-327.3.1.el7.x86_64.rpm
python-perf python-perf-3.10.0-327.3.1.el7.x86_64.rpm