# CVE-2026-31688

> Vulnerability · severity: **HIGH** (CVSS 7.8).

## Description

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

driver core: enforce device_lock for driver_match_device()

Currently, driver_match_device() is called from three sites. One site
(__device_attach_driver) holds device_lock(dev), but the other two
(bind_store and __driver_attach) do not. This inconsistency means that
bus match() callbacks are not guaranteed to be called with the lock
held.

Fix this by introducing driver_match_device_locked(), which guarantees
holding the device lock using a scoped guard. Replace the unlocked calls
in bind_store() and __driver_attach() with this new helper. Also add a
lock assertion to driver_match_device() to enforce this guarantee.

This consistency also fixes a known race condition. The driver_override
implementation relies on the device_lock, so the missing lock led to the
use-after-free (UAF) reported in Bugzilla for buses using this field.

Stress testing the two newly locked paths for 24 hours with
CONFIG_PROVE_LOCKING and CONFIG_LOCKDEP enabled showed no UAF recurrence
and no lockdep warnings.

## Key facts

- **CVE ID:** CVE-2026-31688
- **Published:** 2026-04-27
- **CVSS severity:** HIGH
- **CVSS base score:** 7.8
- **CWE codes:** CWE-416

## Affected products

- `linux:linux_kernel`

## Primary sources

- NIST NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31688

## Citation

> AI Analytics. CVE-2026-31688. Retrieved 2026-08-17 from https://api.ai-analytics.org/cve/CVE-2026-31688. Derived from NIST NVD. Licensed CC0.

---

*[Dataset catalog](https://api.ai-analytics.org/datasets/) · [AI Analytics](https://api.ai-analytics.org/) · CC0 1.0*