Important: kernel security, bug fix, and enhancement update

Topic

An update for kernel is now available for Red Hat Enterprise Linux 8.4 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 packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: fget: check that the fd still exists after getting a ref to it (CVE-2021-4083)
• kernel: cgroups v1 release_agent feature may allow privilege escalation (CVE-2022-0492)
• kernel: heap out of bounds write in nf_dup_netdev.c (CVE-2022-25636)

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 Fixes:

• Power10 PMU fix for PM_CYC/PM_INST_CMPL ( kernel/perf) (BZ#2040665)
• call traces and packet drops seen after changing mtu of ibmvnic interface. (ibmvnic/ P10/ Everglade) (BZ#2050679)
• zfcp: fix failed recovery on gone remote port, non-NPIV FCP dev (BZ#2050739)
• overlay mount fails with ELOOP (Too many levels of symbolic links) (BZ#2053030)
• Host unable to automatically add namespaces belonging to a new ANA group (BZ#2055466)
• scheduler updates and fixes [None8.4.0.z] (BZ#2056834)
• nf_reinject calls nf_queue_entry_free on an already freed entry->state (BZ#2061445)
• First Packet Latency impacted by mlx5 warning msg (BZ#2067992)
• openvswitch connection tracking sends incorrect flow key for some upcalls (BZ#2068477)
• Backport upstream rcu commits up to v5.10 (BZ#2069819)
• Packages have been upgraded to a later upstream version: kernel (4.18.0) (BZ#2036932)

Enhancement:

• zcrypt DD: Toleration for new IBM Z Crypto Hardware (BZ#2054097)

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 x86_64 - Extended Update Support 8.4 x86_64
• Red Hat Enterprise Linux Server - AUS 8.4 x86_64
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 8.4 s390x
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 8.4 ppc64le
• Red Hat Enterprise Linux Server - TUS 8.4 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.4 aarch64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.4 ppc64le
• Red Hat Enterprise Linux Server for x86_64 - Update Services for SAP Solutions 8.4 x86_64
• Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.4 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 8.4 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.4 aarch64

Fixes

• BZ - 2029923 - CVE-2021-4083 kernel: fget: check that the fd still exists after getting a ref to it
• BZ - 2051505 - CVE-2022-0492 kernel: cgroups v1 release_agent feature may allow privilege escalation
• BZ - 2056830 - CVE-2022-25636 kernel: heap out of bounds write in nf_dup_netdev.c

CVEs

• CVE-2021-4083
• CVE-2022-0492
• CVE-2022-25636

References

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