CVE-2025-39859

Description

In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog The ptp_ocp_detach() only shuts down the watchdog timer if it is pending. However, if the timer handler is already running, the timer_delete_sync() is not called. This leads to race conditions where the devlink that contains the ptp_ocp is deallocated while the timer handler is still accessing it, resulting in use-after-free bugs. The following details one of the race scenarios. (thread 1) | (thread 2) ptp_ocp_remove() | ptp_ocp_detach() | ptp_ocp_watchdog() if (timer_pending(&bp->watchdog))| bp = timer_container_of() timer_delete_sync() | | devlink_free(devlink) //free | | bp-> //use Resolve this by unconditionally calling timer_delete_sync() to ensure the timer is reliably deactivated, preventing any access after free.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

References

• https://git.kernel.org/stable/c/e2a6eabe5304a789b7d40ce2576cd80154255e51 ↗
• https://git.kernel.org/stable/c/aad70bdfc8244616e48c434310cab241a3f17781 ↗
• https://git.kernel.org/stable/c/f10d3c7267ac7387a5129d5506c3c5f2460cfd9b ↗
• https://git.kernel.org/stable/c/8bf935cf789872350b04c1a6468b0a509f67afb2 ↗