Linux Kernel NXP i.MX8 Streaming Cleanup Vulnerability in Media Driver

A vulnerability in the Linux kernel's media driver for NXP i.MX8 ISI has been addressed. The issue arose when streamon and streamoff calls were not balanced, such as when an application was exited with Ctrl+C during streaming. This imbalance prevented the m2m usage_count from reaching zero, causing the ISI channel to remain allocated and not be freed. Additionally, if the input line width exceeded 2K, a warning would be triggered, indicating a potential issue with the channel chaining process.

Impact

The vulnerability could lead to a resource leak, where the ISI channel remains allocated and is not properly freed, potentially causing issues with resource management and availability in applications using the driver.

Reproduction

To reproduce the issue, initiate a streaming session using the NXP i.MX8 ISI media driver. While the streaming is active, interrupt the application using Ctrl+C. This will create an imbalance between the streamon and streamoff calls, preventing the m2m usage_count from reaching zero and causing the ISI channel to remain allocated. If the input line width is set to more than 2K, a warning will be triggered, indicating that the channel chaining process has encountered an issue.

Remediation

The vulnerability has been fixed by adjusting the streaming preparation and cleanup processes. The updated driver now properly handles the streaming lifecycle, ensuring that resources are correctly allocated and freed. Instructions for applying the patch can be found in the Linux kernel stable tree.