Issued:
2018-01-25
Updated:
2018-01-25

RHSA-2018:0152 - Important: kernel-rt security and bug fix update

Synopsis

Important: kernel-rt security and bug fix update

Type/Severity

Security Advisory Important

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.

Security Fix(es):

  • A flaw was found in the Linux kernel's key management system where it was possible for an attacker to escalate privileges or crash the machine. If a user key gets negatively instantiated, an error code is cached in the payload area. A negatively instantiated key may be then be positively instantiated by updating it with valid data. However, the ->update key type method must be aware that the error code may be there. (CVE-2015-8539, Important)

  • It was found that fanout_add() in 'net/packet/af_packet.c' in the Linux kernel, before version 4.13.6, allows local users to gain privileges via crafted system calls that trigger mishandling of packet_fanout data structures, because of a race condition (involving fanout_add and packet_do_bind) that leads to a use-after-free bug. (CVE-2017-15649, Important)

  • A vulnerability was found in the Linux kernel where the keyctl_set_reqkey_keyring() function leaks the thread keyring. This allows an unprivileged local user to exhaust kernel memory and thus cause a DoS. (CVE-2017-7472, Moderate)

Red Hat would like to thank Dmitry Vyukov of Google engineering for reporting CVE-2015-8539.

Bug Fix(es):

  • The kernel-rt packages have been upgraded to 3.10.0-693.15.1 source tree, which provides a number of bug fixes over the previous version. (BZ#1519506)

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.

Affected Products

ProductVersionArch
Red Hat Enterprise Linux for Real Time7x86_64
Red Hat Enterprise Linux for Real Time for x86_64 - Extended Life Cycle Support7x86_64
Red Hat Enterprise Linux for Real Time for NFV7x86_64

Updated Packages

  • kernel-rt-doc-3.10.0-693.17.1.rt56.636.el7.noarch.rpm
  • kernel-rt-kvm-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-trace-debuginfo-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-debug-kvm-debuginfo-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-devel-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-kvm-debuginfo-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-trace-kvm-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-trace-kvm-debuginfo-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-trace-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-debug-kvm-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-debug-devel-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-debug-debuginfo-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-debuginfo-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-debuginfo-common-x86_64-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-trace-devel-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-debug-3.10.0-693.17.1.rt56.636.el7.x86_64.rpm
  • kernel-rt-3.10.0-693.17.1.rt56.636.el7.src.rpm

Fixes

CVEs

References

Additional information