---
id: CVE-2025-38535
title: 'phy: tegra: xusb: Fix unbalanced regulator disable in UTMI PHY mode'
summary: |-
  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 shoul…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 <
    ceb645ac6ce052609ee5c8f819a80e8881789b04
  - >-
    Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 <
    cdcb0ffd6448f6be898956913a42bd08e59fb2ae
  - >-
    Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 <
    1bb85b5c2bd43b687c3d54eb6328917f90dd38fc
  - >-
    Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 <
    5367cdeb75cb6c687ca468450bceb2602ab239d8
  - >-
    Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 <
    ec7f98ff05f0649af0adeb4808c7ba23d6111ef9
  - >-
    Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 <
    eaa420339658615d26c1cc95cd6cf720b9aebfca
  - >-
    Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 <
    cefc1caee9dd06c69e2d807edc5949b329f52b22
  - Linux 5.7
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T21:03:21.360319Z'
published: '2025-08-16'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T21:12:45.841Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-38535'
references:
  - url: 'https://git.kernel.org/stable/c/ceb645ac6ce052609ee5c8f819a80e8881789b04'
  - url: 'https://git.kernel.org/stable/c/cdcb0ffd6448f6be898956913a42bd08e59fb2ae'
  - url: 'https://git.kernel.org/stable/c/1bb85b5c2bd43b687c3d54eb6328917f90dd38fc'
  - url: 'https://git.kernel.org/stable/c/5367cdeb75cb6c687ca468450bceb2602ab239d8'
  - url: 'https://git.kernel.org/stable/c/ec7f98ff05f0649af0adeb4808c7ba23d6111ef9'
  - url: 'https://git.kernel.org/stable/c/eaa420339658615d26c1cc95cd6cf720b9aebfca'
  - url: 'https://git.kernel.org/stable/c/cefc1caee9dd06c69e2d807edc5949b329f52b22'
tags:
  - cve.org
epss: 0.00185
epssPercentile: 0.08119
ingestedAt: '2026-11-05T22:38:31.987Z'
---

## Overview

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 when actually transitioning to/from host
mode.

## Affected

- `Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 < ceb645ac6ce052609ee5c8f819a80e8881789b04`
- `Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 < cdcb0ffd6448f6be898956913a42bd08e59fb2ae`
- `Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 < 1bb85b5c2bd43b687c3d54eb6328917f90dd38fc`
- `Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 < 5367cdeb75cb6c687ca468450bceb2602ab239d8`
- `Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 < ec7f98ff05f0649af0adeb4808c7ba23d6111ef9`
- `Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 < eaa420339658615d26c1cc95cd6cf720b9aebfca`
- `Linux >= 49d46e3c7e597e8b00c6fc16e6fd7a92044f4371 < cefc1caee9dd06c69e2d807edc5949b329f52b22`
- `Linux 5.7`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.