Linux Kernel BPF Soft Lockup Vulnerability in 64KB Page AArch64 Kernels

A vulnerability in the Linux kernel's BPF implementation can lead to a segmentation fault and soft lockup on AArch64 kernels with 64KB page size. This issue arises in arena_htab tests, where the function arena_map_free() calls apply_to_existing_page_range() with an unaligned address, causing the system to enter a soft lockup state. The problem does not occur with 4KB pages on AArch64.

Impact

Exploitation of this vulnerability causes a soft lockup, where the system becomes unresponsive due to a process consuming excessive CPU resources.

Remediation

The vulnerability has been fixed in the official Linux Git repository. Users should upgrade to the latest version.