# CVE-2024-40975: platform/x86: x86-android-tablets: Unregister devices in reverse order

> A use-after-free vulnerability in the x86-android-tablets driver can cause a kernel warning and potential denial of service during device unregistration.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 12 Jul 2024
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2024-40975, DEBIAN-CVE-2024-40975, GHSA-g8xj-4vj8-qmx3, ROOT-OS-DEBIAN-11-CVE-2024-40975, ROOT-OS-DEBIAN-12-CVE-2024-40975, ROOT-OS-UBUNTU-2204-CVE-2024-40975, UBUNTU-CVE-2024-40975

## What is CVE-2024-40975?

CVE-2024-40975 is a medium-severity use after free vulnerability in Linux kernel, published on 12 Jul 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

platform/x86: x86-android-tablets: Unregister devices in reverse order

Not all subsystems support a device getting removed while there are
still consumers of the device with a reference to the device.

One example of this is the regulator subsystem. If a regulator gets
unregistered while there are still drivers holding a reference
a WARN() at drivers/regulator/core.c:5829 triggers, e.g.:

 WARNING: CPU: 1 PID: 1587 at drivers/regulator/core.c:5829 regulator_unregister
 Hardware name: Intel Corp. VALLEYVIEW C0 PLATFORM/BYT-T FFD8, BIOS BLADE_21.X64.0005.R00.1504101516 FFD8_X64_R_2015_04_10_1516 04/10/2015
 RIP: 0010:regulator_unregister
 Call Trace:
  <TASK>
  regulator_unregister
  devres_release_group
  i2c_device_remove
  device_release_driver_internal
  bus_remove_device
  device_del
  device_unregister
  x86_android_tablet_remove

On the Lenovo Yoga Tablet 2 series the bq24190 charger chip also provides
a 5V boost converter output for powering USB devices connected to the micro
USB port, the bq24190-charger driver exports this as a Vbus regulator.

On the 830 (8") and 1050 ("10") models this regulator is controlled by
a platform_device and x86_android_tablet_remove() removes platform_device-s
before i2c_clients so the consumer gets removed first.

But on the 1380 (13") model there is a lc824206xa micro-USB switch
connected over I2C and the extcon driver for that controls the regulator.
The bq24190 i2c-client *must* be registered first, because that creates
the regulator with the lc824206xa listed as its consumer. If the regulator
has not been registered yet the lc824206xa driver will end up getting
a dummy regulator.

Since in this case both the regulator provider and consumer are I2C
devices, the only way to ensure that the consumer is unregistered first
is to unregister the I2C devices in reverse order of in which they were
created.

For consistency and to avoid similar problems in the future change
x86_android_tablet_remove() to unregister all device types in reverse
order.

## Which versions are affected by CVE-2024-40975?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-40975?

Apply the vendor's patch.

## Is CVE-2024-40975 being exploited?

There is no known exploitation of CVE-2024-40975 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-40975 and fix it if it is affected.

What it is: CVE-2024-40975 is a medium-severity use after free vulnerability in Linux kernel, published on 12 Jul 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-40975 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-40975/ (Markdown: https://insights.sbomify.com/CVE-2024-40975/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-40975
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-40975
- OSV: https://osv.dev/vulnerability/CVE-2024-40975

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-40975/
Summaries are generated and may contain mistakes; the official description above is the record.