Important: kernel-rt security and bug fix update

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 8.

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: a use-after-free in cls_route filter implementation may lead to privilege escalation (CVE-2022-2588)
• kernel: information leak in scsi_ioctl() (CVE-2022-0494)
• Kernel: A kernel-info-leak issue in pfkey_register (CVE-2022-1353)
• 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: 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):

• [rhel8-rt] BUG: using __this_cpu_add() in preemptible [00000000] - caller is __mod_memcg_lruvec_state+0x69/0x1c0 (BZ#2122600)
• The latest RHEL 8.6.z4 kernel changes need to be merged into the RT source tree to keep source parity between the two kernels. (BZ#2125396)

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 8 x86_64
• Red Hat Enterprise Linux for Real Time for NFV 8 x86_64

Fixes

• BZ - 2039448 - CVE-2022-0494 kernel: information leak in scsi_ioctl()
• BZ - 2066819 - CVE-2022-1353 Kernel: A kernel-info-leak issue in pfkey_register
• BZ - 2090226 - CVE-2022-23816 CVE-2022-29900 hw: cpu: AMD: RetBleed Arbitrary Speculative Code Execution with Return Instructions
• 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 - 2114849 - CVE-2022-2588 kernel: a use-after-free in cls_route filter implementation may lead to privilege escalation

CVEs

• CVE-2022-0494
• CVE-2022-1353
• CVE-2022-2588
• CVE-2022-23816
• CVE-2022-23825
• CVE-2022-29900
• CVE-2022-29901

References

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