CVE-2025-38535

/// Technical description

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

phy: tegra: xusb: Fix unbalanced regulator disable in UTMI PHY mode

When transitioning from USB_ROLE_DEVICE to USB_ROLE_NONE, the code

assumed that the regulator should be disabled. However, if the regulator

is marked as always-on, regulator_is_enabled() continues to return true,

leading to an incorrect attempt to disable a regulator which is not

enabled.

This can result in warnings such as:

[ 250.155624] WARNING: CPU: 1 PID: 7326 at drivers/regulator/core.c:3004

_regulator_disable+0xe4/0x1a0

[ 250.155652] unbalanced disables for VIN_SYS_5V0

To fix this, we move the regulator control logic into

tegra186_xusb_padctl_id_override() function since it's directly related

to the ID override state. The regulator is now only disabled when the role

transitions from USB_ROLE_HOST to USB_ROLE_NONE, by checking the VBUS_ID

register. This ensures that regulator enable/disable operations are

properly balanced and only occur wh

/// 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