6.1 - RHSA-2015:1978

Problem Description:

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 Moderate 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.

2. Relevant releases/architectures:

Red Hat Enterprise Linux Client (v. 7) - noarch, x86_64 Red Hat Enterprise Linux Client Optional (v. 7) - x86_64 Red Hat Enterprise Linux ComputeNode (v. 7) - noarch, x86_64 Red Hat Enterprise Linux ComputeNode Optional (v. 7) - x86_64 Red Hat Enterprise Linux Server (v. 7) - noarch, ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Server Optional (v. 7) - ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Workstation (v. 7) - noarch, x86_64 Red Hat Enterprise Linux Workstation Optional (v. 7) - x86_64

3. Description:

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

* A flaw was found in the way the Linux kernel's VFS subsystem handled file system locks. A local, unprivileged user could use this flaw to trigger a deadlock in the kernel, causing a denial of service on the system. (CVE-2014-8559, Moderate)

* A buffer overflow flaw was found in the way the Linux kernel's virtio-net subsystem handled certain fraglists when the GRO (Generic Receive Offload) functionality was enabled in a bridged network configuration. An attacker on the local network could potentially use this flaw to crash the system, or, although unlikely, elevate their privileges on the system. (CVE-2015-5156, Moderate)

The CVE-2015-5156 issue was discovered by Jason Wang of Red Hat.

This update also fixes several bugs and adds one enhancement. Refer to the following Knowledgebase article for further information:

https://access.redhat.com/articles/2039563

All kernel users are advised to upgrade to these updated packages, which contain backported patches to correct these issues and add this enhancement. The system must be rebooted for this update to take effect.

4. Solution:

Before applying this update, make sure all previously released errata relevant to your system have been applied.

For details on how to apply this update, refer to:

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

5. Bugs fixed (https://bugzilla.redhat.com/):

1159313 - CVE-2014-8559 kernel: fs: deadlock due to incorrect usage of rename_lock 1243852 - CVE-2015-5156 kernel: buffer overflow with fraglist larger than MAX_SKB_FRAGS + 2 in virtio-net