CVE intelligence and bounded remediation

CVE-2021-47205 — Linux Linux Kernel security vulnerability

Medium CVSS 5.5

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.

Severity
Medium
CVSS
5.5 (3.1)
Published
2024-04-10
CISA KEV
Not currently listed
Ecosystem
linux/kernel
Weaknesses
CWE-401

Affected products

  • linux / linux_kernel

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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