Linux Kernel OCXL Double Free Vulnerability in AFU Info Release Handling

A double free vulnerability has been identified in the Linux kernel's OCXL (OpenCAPI Express Layer) component. The issue arises in the 'ocxl_file_register_afuinfo_release' function, which is called during device unregistration when the reference count of 'info->dev' is zero. This situation creates an unnecessary double free condition, as 'ocxl_afu_put()' and 'kfree()' are called redundantly. The vulnerability has been addressed by modifying the error handling path to include a call to 'free_minor()' before returning, preventing the double free scenario.

Impact

Exploitation of this vulnerability could lead to memory corruption issues, commonly associated with double free vulnerabilities, which can be exploited to execute arbitrary code or cause a denial of service by crashing the system.