CVE-2024-36970

What it actually does

Race condition in iwlwifi module loading after the LED merge can cause deadlock when worker threads are exhausted, preventing completion of dependent work.

Why it matters to the business

Systems with multiple iwlwifi radios may experience kernel deadlocks leading to hangs or degraded wireless operation, increasing downtime risk especially in high-density deployments.

How an attack unfolds

An attacker with local access or ability to influence module loading under load can trigger the deadlock by exhausting worker threads, blocking completion of the iwlwifi initialization path.

How to fix it

Upgrade to Linux kernel 6.9.2 or later, or apply commit d20013259539e2fde2deeac85354851097afdf9e in stable trees; ensure request_module_nowait is used for iwlwifi.

How to confirm the fix worked

Confirm kernel version is 6.9.2+, verify the iwlwifi load path uses request_module_nowait, and test under high radio count and worker load conditions.

Typical attack path

1. Gain local execution context on affected kernel
2. Trigger repeated or concurrent iwlwifi module load requests
3. Exhaust worker thread pool via the regression introduced in 6.9
4. Cause deadlock preventing module load completion

How to detect it

Review kernel logs for iwlwifi module load stalls, worker thread exhaustion messages, or deadlock traces around the LED merge changes; check for presence of older 6.9 kernels with iwlwifi.

What your security team should do

• Prioritize upgrade of all Linux systems running kernels 6.9 to 6.9.2 or newer
• Monitor for wireless driver initialization failures in logs
• Test wireless functionality on multi-radio hardware after patching