CVE-2024-56625

What it actually does

Incorrect use of gpiod_set_value() instead of gpiod_set_value_cansleep() in can_set_termination() triggers warnings and potential issues when the termination GPIO is connected via a sleeping bus such as I2C.

Why it matters to the business

Systems relying on CAN bus termination through GPIO expanders may experience kernel warnings or instability, increasing operational risk for automotive, industrial, or embedded deployments until patched.

How an attack unfolds

An attacker with local access or ability to trigger CAN interface configuration commands can cause the kernel to call the non-sleeping GPIO API on a sleeping GPIO, producing warnings; no remote code execution path is known.

How to fix it

Update the Linux kernel to commit faa0a1975a6fbce30616775216606eb8d6388ea1 or later; apply the corresponding stable or distribution kernel package that replaces gpiod_set_value() with gpiod_set_value_cansleep().

How to confirm the fix worked

Confirm the running kernel contains the fix by checking git commit or package version; test CAN termination configuration on hardware using I2C GPIO expanders and verify absence of the gpiolib warning.

Typical attack path

1. Gain local access or control over CAN interface configuration
2. Invoke ip link set or equivalent that calls can_set_termination()
3. Trigger warning path when GPIO resides behind I2C or similar sleeping controller

How to detect it

Search kernel logs for the gpiolib warning mentioning gpiod_set_value and can_set_termination; correlate with CAN interface configuration events.

What your security team should do

• Prioritize kernel updates on all systems exposing CAN interfaces with GPIO termination
• Review CAN device configurations for use of sleeping GPIOs before and after patching
• Monitor for related kernel warnings in production CAN deployments