CVE-2021-47181

What it actually does

Unchecked return value from platform_get_resource() allows a null pointer to be dereferenced in the musb tusb6010 USB driver, resulting in a kernel memory corruption condition.

Why it matters to the business

Systems may experience unexpected crashes or instability when certain USB hardware configurations are present, leading to downtime and potential data loss in affected Linux environments.

How an attack unfolds

An attacker with local access triggers the vulnerable code path by loading the driver under conditions where platform_get_resource fails to locate the expected resource, causing an immediate null dereference and kernel panic.

How to fix it

Apply the upstream kernel patch that adds the missing return-value check after platform_get_resource. Rebuild and deploy the updated kernel on all affected systems.

How to confirm the fix worked

Confirm the presence of the NULL check immediately following the platform_get_resource call in the tusb6010 driver source; test driver probe under simulated resource failure.

Typical attack path

1. Obtain local access to a Linux system using the affected musb tusb6010 driver
2. Trigger driver initialization or probe routine under resource allocation failure conditions
3. Cause platform_get_resource to return NULL
4. Execute the missing NULL check path leading to dereference and crash

How to detect it

Review kernel ring buffer and dmesg logs for oops traces referencing platform_get_resource or tusb6010; look for unexpected null pointer dereference events during USB driver initialization.

What your security team should do

• Prioritize kernel updates on any systems exposing the tusb6010 USB controller
• Monitor kernel logs for oops or null dereference traces involving musb or tusb6010
• Limit untrusted local access until patches are applied