RHSA-2016:1055 - Security Advisory

Topic

An update for kernel-rt is now available for Red Hat Enterprise MRG 2.5.

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

The following packages have been upgraded to a newer upstream version: kernel-rt (3.10.0-327.18.2). This version provides a number of bug fixes and enhancements, including:

• [scsi] bnx2fc: Fix FCP RSP residual parsing and remove explicit logouts
• [scsi] mpt3sas: Fix for Asynchronous completion of timedout IO and task abort of timedout IO
• [scsi] scsi_error: should not get sense for timeout IO in scsi error handler
• [scsi] Revert libiscsi: Reduce locking contention in fast path
• [mm] madvise: fix MADV_WILLNEED on shmem swapouts
• [cpufreq] intel_pstate: decrease number of "HWP enabled" messages and enable HWP per CPU
• [kernel] sched: Robustify topology setup
• [kernel] sched/fair: Disable tg load_avg/runnable_avg update for root_task_group
• [kernel] sched/fair: Move hot load_avg/runnable_avg into separate cacheline
• [ib] mlx5: Fix RC transport send queue overhead computation
• [fs] nfsd: fix clp->cl_revoked list deletion causing softlock in nfsd
• [fs] ceph: multiple updates

(BZ#1320168)

Security Fix(es):

• A flaw was found in the way the Linux kernel's ASN.1 DER decoder processed certain certificate files with tags of indefinite length. A local, unprivileged user could use a specially crafted X.509 certificate DER file to crash the system or, potentially, escalate their privileges on the system. (CVE-2016-0758, Important)

Red Hat would like to thank Philip Pettersson of Samsung for reporting this issue.

Bug Fix(es):

• The hotplug lock and the console semaphore could be acquired in an incorrect order, which could previously lead to a deadlock causing the system console to freeze. The underlying code has been adjusted to acquire the locks in the correct order, resolving the bug with the console. (BZ#1267425)

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

• MRG Realtime 2 x86_64

Fixes

• BZ - 1300257 - CVE-2016-0758 kernel: tags with indefinite length can corrupt pointers in asn1_find_indefinite_length()
• BZ - 1320168 - update the MRG 2.5.x 3.10 kernel-rt sources

CVEs

• CVE-2016-0758

References

• http://www.redhat.com/security/updates/classification/#normal