Use-After-Free Vulnerability in Linux Kernel Affects PTP OCP Functionality

CVE-2025-39859

What is CVE-2025-39859?

A use-after-free vulnerability has been identified in the PTP OCP implementation within the Linux kernel. This issue arises when the ptp_ocp_detach() function shuts down the watchdog timer only if it is pending. If, however, the timer handler is already executing while the relevant device link is deallocated, it results in race conditions that lead to use-after-free scenarios. The vulnerability can cause serious stability issues as access to freed memory can occur when the timer handler continues to reference deallocated resources. The flaw has been addressed by ensuring that the timer is unconditionally deleted, which prevents such accesses after deallocation.

References