CVE-2026-43319
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-667
- Record status
- Modified
Affected
- Linux Kernel < 6.12.75
- Linux Kernel < 6.18.16
- Linux Kernel < 6.19.6
- Linux Kernel 7.0
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Fix and advisories
- https://git.kernel.org/stable/c/40534d19ed2afb880ecf202dab26a8e7a5808d16
- https://git.kernel.org/stable/c/41ccfac7d302968a4f32b5f7b012d066c5f5cdf8
- https://git.kernel.org/stable/c/e341e18215030af2136836b78508e0d798916df7
- https://git.kernel.org/stable/c/f8431b8672231d378b03176fe74c95adfd3522cf
References
- https://git.kernel.org/stable/c/40534d19ed2afb880ecf202dab26a8e7a5808d16
- https://git.kernel.org/stable/c/41ccfac7d302968a4f32b5f7b012d066c5f5cdf8
- https://git.kernel.org/stable/c/e341e18215030af2136836b78508e0d798916df7
- https://git.kernel.org/stable/c/f8431b8672231d378b03176fe74c95adfd3522cf
- https://git.kernel.org/stable/c/fabfed1afe273717ea33b8aee46b767360edbb80