Important: kernel-rt security and bug fix update

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 9.0 Extended Update Support.

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):

• kernel: KVM: cmpxchg_gpte can write to pfns outside the userspace region (CVE-2022-1158)
• kernel: openvswitch: integer underflow leads to out-of-bounds write in reserve_sfa_size() (CVE-2022-2639)
• kernel: watch queue race condition can lead to privilege escalation (CVE-2022-2959)
• kernel: nfsd buffer overflow by RPC message over TCP with garbage data (CVE-2022-43945)
• hw: cpu: incomplete clean-up of multi-core shared buffers (aka SBDR) (CVE-2022-21123)
• hw: cpu: incomplete clean-up of microarchitectural fill buffers (aka SBDS) (CVE-2022-21125)
• hw: cpu: incomplete clean-up in specific special register write operations (aka DRPW) (CVE-2022-21166)
• hw: cpu: AMD: RetBleed Arbitrary Speculative Code Execution with Return Instructions (CVE-2022-23816, CVE-2022-29900)
• hw: cpu: AMD: Branch Type Confusion (non-retbleed) (CVE-2022-23825)
• hw: cpu: Intel: Post-barrier Return Stack Buffer Predictions (CVE-2022-26373)
• hw: cpu: Intel: RetBleed Arbitrary Speculative Code Execution with Return Instructions (CVE-2022-29901)

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):

• kernel-rt: update RT source tree to the latest RHEL-9.0.z5 Batch (BZ#2137580)
• [DELL EMC 9.0-RT BUG] System is not booting into RT Kernel with perc12 [kernel-rt] (BZ#2139864)

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 for Real Time for x86_64 - 4 years of updates 9.0 x86_64
• Red Hat Enterprise Linux for Real Time for NFV for x86_64 - 4 years of updates 9.0 x86_64

Fixes

• BZ - 2069793 - CVE-2022-1158 kernel: KVM: cmpxchg_gpte can write to pfns outside the userspace region
• BZ - 2084479 - CVE-2022-2639 kernel: openvswitch: integer underflow leads to out-of-bounds write in reserve_sfa_size()
• BZ - 2090226 - CVE-2022-23816 CVE-2022-29900 hw: cpu: AMD: RetBleed Arbitrary Speculative Code Execution with Return Instructions
• BZ - 2090237 - CVE-2022-21123 hw: cpu: incomplete clean-up of multi-core shared buffers (aka SBDR)
• BZ - 2090240 - CVE-2022-21125 hw: cpu: incomplete clean-up of microarchitectural fill buffers (aka SBDS)
• BZ - 2090241 - CVE-2022-21166 hw: cpu: incomplete clean-up in specific special register write operations (aka DRPW)
• BZ - 2103148 - CVE-2022-29901 hw: cpu: Intel: RetBleed Arbitrary Speculative Code Execution with Return Instructions
• BZ - 2103153 - CVE-2022-23825 hw: cpu: AMD: Branch Type Confusion (non-retbleed)
• BZ - 2103681 - CVE-2022-2959 kernel: watch queue race condition can lead to privilege escalation
• BZ - 2115065 - CVE-2022-26373 hw: cpu: Intel: Post-barrier Return Stack Buffer Predictions
• BZ - 2141752 - CVE-2022-43945 kernel: nfsd buffer overflow by RPC message over TCP with garbage data

CVEs

• CVE-2022-1158
• CVE-2022-2639
• CVE-2022-2959
• CVE-2022-21123
• CVE-2022-21125
• CVE-2022-21166
• CVE-2022-23816
• CVE-2022-23825
• CVE-2022-26373
• CVE-2022-29900
• CVE-2022-29901
• CVE-2022-43945

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/solutions/6971358