CVE-2023-53612
Description
A NULL pointer dereference flaw was found in the Linux kernel's coretemp hardware monitoring driver in the platform device handling logic. A local privileged user who disables drivers_autoprobe for the platform bus can trigger this issue by initiating CPU hotplug operations, causing the driver to assume synchronous device binding when it does not occur. This results in a NULL pointer dereference leading to denial of service through a kernel crash or deadlock during suspend operations.
Statement
The coretemp driver uses an unconventional architecture where platform devices are dynamically created and destroyed from CPU hotplug notifiers. The code assumes that platform_device_add() will synchronously bind the driver and set drvdata before returning, but this assumption breaks when drivers_autoprobe is disabled for the platform bus. When hotplug events occur under these conditions, the driver dereferences uninitialized drvdata, causing a NULL pointer dereference. Additionally, the approach of managing platform devices from hotplug notifiers creates deadlock potential during system suspend and lockdep issues when other subsystems register CPU hotplug notifiers from platform bus notifiers.
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.1 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | High | Low | N/A |
| Privileges Required | High | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
NVD: 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
NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.
Integrity,Confidentiality
Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory
In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.
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