CVE-2026-98529

What it actually does

Runtime PM reference leak occurs in arizona_gpio_direction_out when a persistent GPIO line is switched from input to output and regmap_update_bits subsequently fails, leaving an acquired reference on the parent device that cannot be balanced by later direction_in calls.

Why it matters to the business

Repeated triggering of the error path may prevent the affected device from entering low-power states, leading to elevated power consumption, reduced battery life on embedded systems, and gradual degradation of system stability in Linux-based products using Arizona codecs.

How an attack unfolds

An attacker with local access would need to repeatedly invoke GPIO direction changes that hit the failing regmap_update_bits path to accumulate leaked references; the low EPSS and absence from KEV indicate this is unlikely to be weaponized in real-world attacks.

How to fix it

Apply the upstream kernel commit that drops the runtime PM reference on the update failure path; rebuild and deploy the fixed kernel image to all affected systems.

How to confirm the fix worked

Review the arizona_gpio_direction_out function to confirm the reference drop occurs on the regmap failure path; monitor kernel runtime PM usage counters before and after GPIO operations that previously failed.

Typical attack path

1. Obtain local code execution or user privileges on the target system
2. Trigger GPIO direction output operations on an Arizona-managed line that cause regmap_update_bits to fail
3. Repeat to accumulate leaked runtime PM references
4. Observe gradual power-management degradation

How to detect it

Search kernel logs and runtime PM debug output for repeated unbalanced reference warnings or increasing reference counts on Arizona parent devices; use ftrace or similar to trace arizona_gpio_direction_out failures.

What your security team should do

• Prioritize patching Linux kernels on devices using Arizona GPIO drivers within normal maintenance windows
• Monitor EPSS and KEV updates for any future elevation in exploitability
• Include the fixed kernel in the next scheduled OS image release for embedded products