0.0
NA
CVE-2026-43319
spi: spidev: fix lock inversion between spi_lock and buf_lock
Description

In the Linux kernel, the following vulnerability has been resolved: spi: spidev: fix lock inversion between spi_lock and buf_lock The spidev driver previously used two mutexes, spi_lock and buf_lock, but acquired them in different orders depending on the code path: write()/read(): buf_lock -> spi_lock ioctl(): spi_lock -> buf_lock This AB-BA locking pattern triggers lockdep warnings and can cause real deadlocks: WARNING: possible circular locking dependency detected spidev_ioctl() -> mutex_lock(&spidev->buf_lock) spidev_sync_write() -> mutex_lock(&spidev->spi_lock) *** DEADLOCK *** The issue is reproducible with a simple userspace program that performs write() and SPI_IOC_WR_MAX_SPEED_HZ ioctl() calls from separate threads on the same spidev file descriptor. Fix this by simplifying the locking model and removing the lock inversion entirely. spidev_sync() no longer performs any locking, and all callers serialize access using spi_lock. buf_lock is removed since its functionality is fully covered by spi_lock, eliminating the possibility of lock ordering issues. This removes the lock inversion and prevents deadlocks without changing userspace ABI or behaviour.

INFO

Published Date :

May 8, 2026, 2:16 p.m.

Last Modified :

May 8, 2026, 2:16 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2026-43319 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Simplify locking model by removing buf_lock and unifying access via spi_lock.
  • Update the Linux kernel to resolve lock inversion issues.
  • Ensure all callers serialize access using spi_lock.
  • Remove the buf_lock from the spidev driver.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-43319 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-43319 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-43319 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-43319 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 08, 2026

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: spi: spidev: fix lock inversion between spi_lock and buf_lock The spidev driver previously used two mutexes, spi_lock and buf_lock, but acquired them in different orders depending on the code path: write()/read(): buf_lock -> spi_lock ioctl(): spi_lock -> buf_lock This AB-BA locking pattern triggers lockdep warnings and can cause real deadlocks: WARNING: possible circular locking dependency detected spidev_ioctl() -> mutex_lock(&spidev->buf_lock) spidev_sync_write() -> mutex_lock(&spidev->spi_lock) *** DEADLOCK *** The issue is reproducible with a simple userspace program that performs write() and SPI_IOC_WR_MAX_SPEED_HZ ioctl() calls from separate threads on the same spidev file descriptor. Fix this by simplifying the locking model and removing the lock inversion entirely. spidev_sync() no longer performs any locking, and all callers serialize access using spi_lock. buf_lock is removed since its functionality is fully covered by spi_lock, eliminating the possibility of lock ordering issues. This removes the lock inversion and prevents deadlocks without changing userspace ABI or behaviour.
    Added Reference https://git.kernel.org/stable/c/40534d19ed2afb880ecf202dab26a8e7a5808d16
    Added Reference https://git.kernel.org/stable/c/41ccfac7d302968a4f32b5f7b012d066c5f5cdf8
    Added Reference https://git.kernel.org/stable/c/e341e18215030af2136836b78508e0d798916df7
    Added Reference https://git.kernel.org/stable/c/f8431b8672231d378b03176fe74c95adfd3522cf
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.