Description
In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus) Fix passing events to regulator core Sashiko reports: Commit 754bd2b4a084 ("hwmon: (pmbus/core) Protect regulator operations with mutex") introduced a worker to batch regulator events over time using atomic_or(). The delayed worker then passes the combined bitmask unmodified to regulator_notifier_call_chain(). The core regulator subsystem's regulator_handle_critical() function evaluates the event parameter using a strict switch statement. If multiple distinct faults occur before the worker runs (e.g., REGULATOR_EVENT_UNDER_VOLTAGE | REGULATOR_EVENT_OVER_CURRENT), the combined bitmask fails to match any case. This leaves the reason as NULL and completely bypasses the critical hw_protection_trigger(). Fix the problem by passing events bit by bit to the regulator event handler.
References5
- git.kernel.org/stable/c/2106bf4056858fcce3624e0c51f6fee4d41d3f2f
- git.kernel.org/stable/c/489291b6b56978cc50d34e8e13f9636ea296ba8a
- git.kernel.org/stable/c/48fe43666950efefb7ac5fbdc012c1b3604096bf
- git.kernel.org/stable/c/9ef7dacd44216bf5ea05c8aef49eba4d145f4047
- git.kernel.org/stable/c/b0ff6b6ae9c5183ef701ece7016698bde5a5bfba
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - EPSS — exploit probability
- 0% percentile: 8 · as of 11 November 2026
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