CVE-2025-38535
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.17%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 when actually transitioning to/from host mode.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.17% probability · 6th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel · debian/debian linux
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/1bb85b5c2bd43b687c3d54eb6328917f90dd38fcPatch
- https://git.kernel.org/stable/c/5367cdeb75cb6c687ca468450bceb2602ab239d8Patch
- https://git.kernel.org/stable/c/cdcb0ffd6448f6be898956913a42bd08e59fb2aePatch
- https://git.kernel.org/stable/c/ceb645ac6ce052609ee5c8f819a80e8881789b04Patch
- https://git.kernel.org/stable/c/cefc1caee9dd06c69e2d807edc5949b329f52b22Patch
- https://git.kernel.org/stable/c/eaa420339658615d26c1cc95cd6cf720b9aebfcaPatch
- https://git.kernel.org/stable/c/ec7f98ff05f0649af0adeb4808c7ba23d6111ef9Patch
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.htmlMailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.