Important: kernel security and bug fix 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: Small table perturb size in the TCP source port generation algorithm can lead to information leak (CVE-2022-1012)
• kernel: race condition in perf_event_open leads to privilege escalation (CVE-2022-1729)
• kernel: a use-after-free write in the netfilter subsystem can lead to privilege escalation to root (CVE-2022-32250)
• kernel: cgroup: Use open-time creds and namespace for migration perm checks (CVE-2021-4197)
• kernel: Race condition in races in sk_peer_pid and sk_peer_cred accesses (CVE-2021-4203)
• kernel: the copy-on-write implementation can grant unintended write access because of a race condition in a THP mapcount check (CVE-2020-29368)

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):

• Failed to reboot after crash trigger (BZ#2060747)
• conntrack entries linger around after test (BZ#2066357)
• Enable nested virtualization (BZ#2079070)
• slub corruption during LPM of hnv interface (BZ#2081251)
• sleeping function called from invalid context at kernel/locking/spinlock_rt.c:35 (BZ#2082091)
• Backport request of "genirq: use rcu in kstat_irqs_usr()" (BZ#2083309)
• ethtool -L may cause system to hang (BZ#2083323)
• For isolated CPUs (with nohz_full enabled for isolated CPUs) CPU utilization statistics are not getting reflected continuously (BZ#2084139)
• Affinity broken due to vector space exhaustion (BZ#2084647)
• kernel memory leak while freeing nested actions (BZ#2086597)
• sync rhel-8.6 with upstream 5.13 through 5.16 fixes and improvements (BZ#2088037)
• Kernel panic possibly when cleaning namespace on pod deletion (BZ#2089539)
• Softirq hrtimers are being placed on the per-CPU softirq clocks on isolcpu’s. (BZ#2090485)
• fix missed wake-ups in rq_qos_throttle try two (BZ#2092076)
• NFS4 client experiencing IO outages while sending duplicate SYNs and erroneous RSTs during connection reestablishment (BZ#2094334)
• using __this_cpu_read() in preemptible [00000000] code: kworker/u66:1/937154 (BZ#2095775)
• Need some changes in RHEL8.x kernels. (BZ#2096932)

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 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 - 1903244 - CVE-2020-29368 kernel: the copy-on-write implementation can grant unintended write access because of a race condition in a THP mapcount check
• BZ - 2035652 - CVE-2021-4197 kernel: cgroup: Use open-time creds and namespace for migration perm checks
• BZ - 2036934 - CVE-2021-4203 kernel: Race condition in races in sk_peer_pid and sk_peer_cred accesses
• BZ - 2064604 - CVE-2022-1012 kernel: Small table perturb size in the TCP source port generation algorithm can lead to information leak
• BZ - 2086753 - CVE-2022-1729 kernel: race condition in perf_event_open leads to privilege escalation
• BZ - 2092427 - CVE-2022-32250 kernel: a use-after-free write in the netfilter subsystem can lead to privilege escalation to root

CVEs

• CVE-2020-29368
• CVE-2021-4197
• CVE-2021-4203
• CVE-2022-1012
• CVE-2022-1729
• CVE-2022-32250

References

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