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Fencer Vulns
no cvss —

CVE-2022-50771 json

rcu: Fix __this_cpu_read() lockdep warning in rcu_force_quiescent_state()

published 2025-12-24 10 mo ago modified 2026-06-17 4 mo ago also EUVD-2022-55790

cvss
—
not scored
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

rcu: Fix __this_cpu_read() lockdep warning in rcu_force_quiescent_state()

Running rcutorture with non-zero fqs_duration module parameter in a kernel built with CONFIG_PREEMPTION=y results in the following splat:

BUG: using __this_cpu_read() in preemptible [00000000] code: rcu_torture_fqs/398 caller is __this_cpu_preempt_check+0x13/0x20 CPU: 3 PID: 398 Comm: rcu_torture_fqs Not tainted 6.0.0-rc1-yoctodev-standard+ Call Trace: <TASK> dump_stack_lvl+0x5b/0x86 dump_stack+0x10/0x16 check_preemption_disabled+0xe5/0xf0 __this_cpu_preempt_check+0x13/0x20 rcu_force_quiescent_state.part.0+0x1c/0x170 rcu_force_quiescent_state+0x1e/0x30 rcu_torture_fqs+0xca/0x160 ? rcu_torture_boost+0x430/0x430 kthread+0x192/0x1d0 ? kthread_complete_and_exit+0x30/0x30 ret_from_fork+0x22/0x30 </TASK>

The problem is that rcu_force_quiescent_state() uses __this_cpu_read() in preemptible code instead of the proper raw_cpu_read(). This commit therefore changes __this_cpu_read() to raw_cpu_read().

Patch / fix

  • Linux Linux 5.4.229, 5.10.163, 5.15.86, 6.0.16, 6.1.2, 6.2
  • linux Debian 14, Debian 13, Debian 12 6.1.4-1

debian advisories DEBIAN-CVE-2022-50771

  • linux Ubuntu 20.04 LTS 5.4.0-144.161
  • linux Ubuntu 22.04 LTS 5.15.0-69.76
  • linux-aws Ubuntu 20.04 LTS 5.4.0-1097.105
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1033.37
  • linux-gcp Ubuntu 20.04 LTS 5.4.0-1101.110
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1031.38
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1030.35
  • linux-ibm Ubuntu 20.04 LTS 5.4.0-1045.50

ubuntu advisories UBUNTU-CVE-2022-50771

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel RHEL 9 5.14.0-362.8.1.el9_3
  • rv RHEL 9 5.14.0-362.8.1.el9_3
  • perf RHEL 9 5.14.0-362.8.1.el9_3
  • rtla RHEL 9 5.14.0-362.8.1.el9_3
  • bpftool RHEL 9 7.2.0-362.8.1.el9_3
  • libperf RHEL 9 5.14.0-362.8.1.el9_3
  • kernel-rt RHEL 9 5.14.0-362.8.1.el9_3
  • kernel-64k RHEL 9 5.14.0-362.8.1.el9_3

red hat advisories RHSA-2023:6583

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2022-50771 updated cvss 5.5

kernel: rcu: Fix __this_cpu_read() lockdep warning in rcu_force_quiescent_state()

  • Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    affected: no fix available “Fix deferred”
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 10 kernel
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-08).

Affected products

  • Linux Linux

Classification

Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.