Linux Kernel Memory Management Vulnerability in split_large_buddy() Function

A vulnerability in the Linux kernel's memory management code can lead to a null pointer dereference. This issue arises in the split_large_buddy() function, where the pfn_to_page() function may be called on a page frame number (PFN) that does not exist. This situation can occur in specific scenarios, such as freeing the highest page block in the last memory section, particularly with CONFIG_SPARSEMEM enabled and CONFIG_SPARSEMEM_EXTREME disabled. The problem was identified through code inspection.

Impact

Exploitation of this vulnerability can lead to a null pointer dereference, causing a kernel crash.

Remediation

The vulnerability has been fixed in the Linux kernel. Users should upgrade to the latest stable version.