CVE-2025-40239

In the Linux kernel, the following vulnerability has been resolved:

net: phy: micrel: always set shared->phydev for LAN8814

Currently, during the LAN8814 PTP probe shared->phydev is only set if PTP clock gets actually set, otherwise the function will return before setting it.

This is an issue as shared->phydev is unconditionally being used when IRQ is being handled, especially in lan8814_gpio_process_cap and since it was not set it will cause a NULL pointer exception and crash the kernel.

So, simply always set shared->phydev to avoid the NULL pointer exception.

The change hardens the LAN8814 PTP probe path by always initializing shared->phydev so that IRQ handlers cannot dereference NULL if PTP clock registration fails. Impact is limited to systems with the LAN8814 PHY and results in a local kernel crash (DoS).

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.