CVE-2022-50582

Description

From CVE.org

In the Linux kernel, the following vulnerability has been resolved: regulator: core: Prevent integer underflow By using a ratio of delay to poll_enabled_time that is not integer time_remaining underflows and does not exit the loop as expected. As delay could be derived from DT and poll_enabled_time is defined in the driver this can easily happen. Use a signed iterator to make sure that the loop exits once the remaining time is negative.

Statement

The enable path used an unsigned int time_remaining. When the computed delay went negative, it underflowed and wrapped to a large positive value, preventing the loop from terminating and potentially stalling regulator enable (DoS on the code path, possibly during boot). The fix switches time_remaining to a signed int so the loop exits once the remaining time becomes negative. Privileged/local code (drivers or root via regulator controls) is typically required to reach this path.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.5N/AN/A
Attack VectorLocalN/AN/A
Attack ComplexityLowN/AN/A
Privileges RequiredLowN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityNoneN/AN/A
Integrity ImpactNoneN/AN/A
Availability ImpactHighN/AN/A

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Instability

This weakness will generally lead to undefined behavior and therefore crashes. In the case of overflows involving loop index variables, the likelihood of infinite loops is also high.

Integrity

Technical Impact: Modify Memory

If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.

Confidentiality,Availability,Access Control

Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism

This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.

Frequently Asked Questions

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