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Red Hat 6.2 RHSA-2016:2132-01 Important Memory Management Risk

red hat
Calendar Grey November 1, 2016
Scroller Redhat
Crucial patch released for Ubuntu's core system tackling resource allocation and addressing vulnerabilities inherent in the Linux environment.
An update for kernel is now available for Red Hat Enterprise Linux 6.2 Advanced Update Support

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

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

The system must be rebooted for this update to take effect.

Summary

The kernel packages contain the Linux kernel, the core of any Linux operating system.
Security Fix(es):
* A race condition was found in the way the Linux kernel's memory subsystem handled the copy-on-write (COW) breakage of private read-only memory mappings. An unprivileged, local user could use this flaw to gain write access to otherwise read-only memory mappings and thus increase their privileges on the system. (CVE-2016-5195, Important)
Red Hat would like to thank Phil Oester for reporting this issue.
Bug Fix(es):
* Previously, the BUG_ON() signal appeared in the fs_clear_inode() function where the nfs_have_writebacks() function reported a positive value for nfs_inode->npages. As a consequence, a kernel panic occurred. The provided patch performs a serialization by holding the inode i_lock over the check of PagePrivate and locking the request, which fixes this bug. (BZ#1365157)

Topics%20covered

Topics Covered

security advisory Red Hat bug fix important kernel memory management exploit risk

References

https://access.redhat.com/security/cve/CVE-2016-5195 https://access.redhat.com/security/updates/classification#important

Package List

Red Hat Enterprise Linux Server AUS (v. 6.2):
Source: kernel-2.6.32-220.68.1.el6.src.rpm
noarch: kernel-doc-2.6.32-220.68.1.el6.noarch.rpm kernel-firmware-2.6.32-220.68.1.el6.noarch.rpm
x86_64: kernel-2.6.32-220.68.1.el6.x86_64.rpm kernel-debug-2.6.32-220.68.1.el6.x86_64.rpm kernel-debug-debuginfo-2.6.32-220.68.1.el6.x86_64.rpm kernel-debug-devel-2.6.32-220.68.1.el6.x86_64.rpm kernel-debuginfo-2.6.32-220.68.1.el6.x86_64.rpm kernel-debuginfo-common-x86_64-2.6.32-220.68.1.el6.x86_64.rpm kernel-devel-2.6.32-220.68.1.el6.x86_64.rpm kernel-headers-2.6.32-220.68.1.el6.x86_64.rpm perf-2.6.32-220.68.1.el6.x86_64.rpm perf-debuginfo-2.6.32-220.68.1.el6.x86_64.rpm python-perf-debuginfo-2.6.32-220.68.1.el6.x86_64.rpm
Red Hat Enterprise Linux Server Optional AUS (v. 6.2):
Source: kernel-2.6.32-220.68.1.el6.src.rpm
x86_64: kernel-debug-debuginfo-2.6.32-220.68.1.el6.x86_64.rpm kernel-debuginfo-2.6.32-220.68.1.el6.x86_64.rpm kernel-debuginfo-common-x86_64-2.6.32-220.68.1.el6.x86_64.rpm perf-debuginfo-2.6.32-220.68.1.el6.x86_64.rpm python-perf-2.6.32-220.68.1.el6.x86_64.rpm python-perf-debuginfo-2.6.32-220.68.1.el6.x86_64.rpm
These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from https://access.redhat.com/security/team/key


Severity
important
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2016:2132-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2016:2132.html
Issue date: 2016-11-01

Topic

An update for kernel is now available for Red Hat Enterprise Linux 6.2Advanced Update Support.Red Hat Product Security has rated this update as having a security impactof Important. A Common Vulnerability Scoring System (CVSS) base score,which gives a detailed severity rating, is available for each vulnerabilityfrom the CVE link(s) in the References section.

Topics%20covered

Topics Covered

security advisory Red Hat bug fix important kernel memory management exploit risk

Relevant Releases Architectures

Red Hat Enterprise Linux Server AUS (v. 6.2) - noarch, x86_64

Red Hat Enterprise Linux Server Optional AUS (v. 6.2) - x86_64

Bugs Fixed

1384344 - CVE-2016-5195 kernel: mm: privilege escalation via MAP_PRIVATE COW breakage

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