CVE-2025-38537

/// Technical description

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

net: phy: Don't register LEDs for genphy

If a PHY has no driver, the genphy driver is probed/removed directly in

phy_attach/detach. If the PHY's ofnode has an "leds" subnode, then the

LEDs will be (un)registered when probing/removing the genphy driver.

This could occur if the leds are for a non-generic driver that isn't

loaded for whatever reason. Synchronously removing the PHY device in

phy_detach leads to the following deadlock:

rtnl_lock()

ndo_close()

...

phy_detach()

phy_remove()

phy_leds_unregister()

led_classdev_unregister()

led_trigger_set()

netdev_trigger_deactivate()

unregister_netdevice_notifier()

rtnl_lock()

There is a corresponding deadlock on the open/register side of things

(and that one is reported by lockdep), but it requires a race while this

one is det

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References