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Fencer Vulns
medium 5.5

CVE-2021-47205 json

clk: sunxi-ng: Unregister clocks/resets when unbinding

published 2024-04-10 2 y ago modified 2026-06-17 4 mo ago also EUVD-2021-33853

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 9%
public exploits
0
none known

Summary

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

clk: sunxi-ng: Unregister clocks/resets when unbinding

Currently, unbinding a CCU driver unmaps the device's MMIO region, while leaving its clocks/resets and their providers registered. This can cause a page fault later when some clock operation tries to perform MMIO. Fix this by separating the CCU initialization from the memory allocation, and then using a devres callback to unregister the clocks and resets.

This also fixes a memory leak of the `struct ccu_reset`, and uses the correct owner (the specific platform driver) for the clocks and resets.

Early OF clock providers are never unregistered, and limited error handling is possible, so they are mostly unchanged. The error reporting is made more consistent by moving the message inside of_sunxi_ccu_probe.

Patch / fix

  • Linux Linux 5.15.5, 5.16
  • linux Debian 14, Debian 13, Debian 12 5.15.5-1

debian advisories DEBIAN-CVE-2021-47205

  • kernel-syms SLES for SAP 12 SP5, SLES 12 SP5 4.12.14-122.216.1
  • kernel-source SLES for SAP 12 SP5, SLES 12 SP5 4.12.14-122.216.1
  • kernel-default SLES for SAP 12 SP5, SLES 12 SP5, SLE Workstation Extension 12 SP5 +2 more 4.12.14-122.216.1
  • kernel-obs-build SLE Software Development Kit 12 SP5 4.12.14-122.216.1
  • kernel-rt SLE Micro 5.5, Real Time Module 15 SP5, openSUSE Leap 15.5 5.14.21-150500.13.52.1
  • kernel-syms-rt Real Time Module 15 SP5, openSUSE Leap 15.5 5.14.21-150500.13.52.1
  • kernel-rt_debug Real Time Module 15 SP5, openSUSE Leap 15.5 5.14.21-150500.13.52.1
  • kernel-source-rt SLE Micro 5.5, Real Time Module 15 SP5, openSUSE Leap 15.5 5.14.21-150500.13.52.1

suse advisories SUSE-SU-2024:1870-1SUSE-SU-2024:1663-1SUSE-SU-2024:1659-1SUSE-SU-2024:1647-1SUSE-SU-2024:1646-1SUSE-SU-2024:1644-1

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-2021-47205 updated cvss 6.0

kernel: clk: sunxi-ng: Unregister clocks/resets when unbinding

  • 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 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
    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

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.20% chance of exploitation in the next 30 days, higher than 9% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Linux Linux

Classification

Weakness
  • CWE-401 Missing Release of Memory after Effective Lifetime
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.