RHSA-2019:2900 - Security Advisory

Topic

An update for kernel is now available for Red Hat Enterprise Linux 7.3 Advanced Update Support, Red Hat Enterprise Linux 7.3 Telco Extended Update Support, and Red Hat Enterprise Linux 7.3 Update Services for SAP Solutions.

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

Security Fix(es):

• A buffer overflow flaw was found in the way Linux kernel's vhost functionality that translates virtqueue buffers to IOVs, logged the buffer descriptors during migration. A privileged guest user able to pass descriptors with invalid length to the host when migration is underway, could use this flaw to increase their privileges on the host. (CVE-2019-14835)
• kernel: hw: Spectre SWAPGS gadget vulnerability (CVE-2019-1125)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• fs deadlock when a memory allocation waits on page writeback in NOFS context (BZ#1729105)
• fragmented packets timing out (BZ#1729410)
• kernel build: speed up debuginfo extraction (BZ#1731461)
• use "make -jN" for modules_install (BZ#1735080)
• shmem: consider shm_mnt as a long-term mount (BZ#1737375)
• Backport TCP follow-up for small buffers (BZ#1739126)

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

• Red Hat Enterprise Linux Server - AUS 7.3 x86_64
• Red Hat Enterprise Linux Server - TUS 7.3 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.3 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.3 x86_64

Fixes

• BZ - 1724389 - CVE-2019-1125 kernel: hw: Spectre SWAPGS gadget vulnerability
• BZ - 1750727 - CVE-2019-14835 kernel: vhost-net: guest to host kernel escape during migration

CVEs

• CVE-2019-1125
• CVE-2019-14835

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/articles/4329821
• https://access.redhat.com/security/vulnerabilities/kernel-vhost