CVE-2022-3111

What it actually does

Missing call to free WM8350_IRQ_CHG_FAST_RDY in free_charger_irq() after registration in wm8350_init_charger() leaves a dangling IRQ handler registration, enabling memory corruption via use-after-free or resource leak on affected power supply drivers.

Why it matters to the business

Local denial-of-service or system instability on Linux systems using the wm8350 power management chip, potentially requiring reboots or causing unexpected downtime in embedded or server environments; low urgency given four-year age and minimal exploitation signals.

How an attack unfolds

A local attacker with low privileges loads or triggers the wm8350_power driver, causes the charger initialization path to register the IRQ, then triggers module unload or error paths that invoke the incomplete free function, resulting in a dangling reference that can be abused for kernel memory corruption.

How to fix it

Upgrade the Linux kernel to a version containing the fix for the missing IRQ free (post-5.16-rc6 releases) and rebuild any custom kernels with the corrected wm8350_power.c driver.

How to confirm the fix worked

Confirm kernel source contains paired free for WM8350_IRQ_CHG_FAST_RDY in free_charger_irq(); verify running kernel version is newer than 5.16-rc6 and test driver load/unload cycles for clean IRQ release.

Typical attack path

1. Obtain local shell on target Linux system
2. Trigger wm8350 charger initialization via hardware or module load
3. Force driver unload or error path to execute incomplete IRQ free
4. Leverage resulting dangling IRQ reference for memory corruption or crash

How to detect it

Review kernel logs for IRQ-related warnings or oops during wm8350 module load/unload; inspect dmesg and /var/log/kern.log for charger IRQ registration errors on systems with wm8350 hardware.

What your security team should do

• Prioritize kernel upgrades on systems exposing the wm8350 driver
• Audit custom kernels and embedded images for the incomplete free_charger_irq function
• Monitor for local privilege escalation attempts on affected hosts