In the Linux kernel, the following vulnerability has been resolved: hwmon: (w83791d) Convert macros to functions to avoid TOCTOU The macro FAN_FROM_REG evaluates its arguments multiple times. When used in lockless contexts involving shared driver data, this leads to Time-of-Check to Time-of-Use (TOCTOU) race conditions, potentially causing divide-by-zero errors. Convert the macro to a static function. This guarantees that arguments are evaluated only once (pass-by-value), preventing the race conditions. Additionally, in store_fan_div, move the calculation of the minimum limit inside the update lock. This ensures that the read-modify-write sequence operates on consistent data. Adhere to the principle of minimal changes by only converting macros that evaluate arguments multiple times and are used in lockless contexts.

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

Vendors Products
Linux
  • Linux Kernel

No data.

No data.

References
Link Providers
https://git.kernel.org/stable/c/3dceb68f6ad33156032ef4da21a93d84059cca6d cve-icon cve-icon
https://git.kernel.org/stable/c/670d7ef945d3a84683594429aea6ab2cdfa5ceb4 cve-icon cve-icon
https://git.kernel.org/stable/c/a9fb6e8835a22f5796c1182ed612daed3fd273af cve-icon cve-icon
https://git.kernel.org/stable/c/bf5b03227f2e6d4360004886d268f9df8993ef8f cve-icon cve-icon
https://git.kernel.org/stable/c/c8cf0c2bdcccc6634b6915ff793b844e12436680 cve-icon cve-icon
https://git.kernel.org/stable/c/f2b579a0c37c0df19603d719894a942a295f634a cve-icon cve-icon
https://git.kernel.org/stable/c/f94800fbc26ccf7c81eb791707b038a57aa39a18 cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2026011412-CVE-2025-71111-1547@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2025-71111 cve-icon
https://www.cve.org/CVERecord?id=CVE-2025-71111 cve-icon
History

Mon, 19 Jan 2026 12:45:00 +0000

Type Values Removed Values Added
References

Thu, 15 Jan 2026 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low

Wed, 14 Jan 2026 15:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: hwmon: (w83791d) Convert macros to functions to avoid TOCTOU The macro FAN_FROM_REG evaluates its arguments multiple times. When used in lockless contexts involving shared driver data, this leads to Time-of-Check to Time-of-Use (TOCTOU) race conditions, potentially causing divide-by-zero errors. Convert the macro to a static function. This guarantees that arguments are evaluated only once (pass-by-value), preventing the race conditions. Additionally, in store_fan_div, move the calculation of the minimum limit inside the update lock. This ensures that the read-modify-write sequence operates on consistent data. Adhere to the principle of minimal changes by only converting macros that evaluate arguments multiple times and are used in lockless contexts.
Title hwmon: (w83791d) Convert macros to functions to avoid TOCTOU
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2026-01-14T15:05:58.649Z

Updated: 2026-01-19T12:20:13.246Z

Reserved: 2026-01-13T15:30:19.653Z

Link: CVE-2025-71111

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-01-14T15:16:00.193

Modified: 2026-01-19T13:16:18.260

Link: CVE-2025-71111

cve-icon Redhat

Severity : Low

Publid Date: 2026-01-14T00:00:00Z

Links: CVE-2025-71111 - Bugzilla