UBUNTU-CVE-2026-43319: Medium severity ubuntu/linux-hwe-edge vulnerability

Q: Who is exposed to this issue?

Systems using the affected Ubuntu kernel packages and the spidev driver are exposed when userspace can access the same spidev file descriptor from concurrent threads.

Q: What is required to trigger the deadlock?

A local userspace program must perform write() or read() operations and SPI_IOC_WR_MAX_SPEED_HZ ioctl() calls concurrently from separate threads on the same spidev file descriptor. The issue requires high privileges according to the supplied severity vector.

Q: What is the impact if the issue is triggered?

The conflicting lock acquisition order can cause a real kernel-side deadlock, resulting in loss of availability. The supplied vector indicates no confidentiality or integrity impact.

Q: How can I determine whether this is occurring?

Kernel lockdep output may report a possible circular locking dependency involving spidev_ioctl(), spidev_sync_write(), spidev->buf_lock, and spidev->spi_lock. Affected workloads may also hang while concurrently issuing spidev reads or writes and speed-setting ioctls.

Published May 8, 2026

Updated

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

Affected Software

149 affected componentsFixes available

ubuntu/linux-hwe-edge*

ubuntu/linux-aws-5.0*

ubuntu/linux-aws-5.3*

ubuntu/linux-azure*

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-5.3*

ubuntu/linux-gke-4.15*

ubuntu/linux-gke-5.4*

ubuntu/linux-gkeop-5.4*

ubuntu/linux-hwe*

ubuntu/linux-hwe-edge*

ubuntu/linux-oem*

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.8*

ubuntu/linux-gke*

ubuntu/linux-gke-5.15*

ubuntu/linux-gkeop*

ubuntu/linux-gkeop-5.15*

ubuntu/linux-hwe-5.11*

ubuntu/linux-hwe-5.13*

ubuntu/linux-hwe-5.8*

ubuntu/linux-intel-5.13*

ubuntu/linux-oem-5.10*

ubuntu/linux-oem-5.13*

ubuntu/linux-oem-5.6*

ubuntu/linux-oracle-5.11*

ubuntu/linux-oracle-5.13*

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.8*

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-aws-6.8<6.8.0-1060.63~22.04.1

6.8.0-1060.63~22.04.1

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-6.8<6.8.0-1063.71~22.04.1

6.8.0-1063.71~22.04.1

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-azure-fde-6.8<6.8.0-1062.69~22.04.1

6.8.0-1062.69~22.04.1

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-gcp-6.8<6.8.0-1063.69~22.04.1

6.8.0-1063.69~22.04.1

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-hwe-6.8<6.8.0-136.136~22.04.1

6.8.0-136.136~22.04.1

ubuntu/linux-ibm-6.8<6.8.0-1060.61~22.04.1

6.8.0-1060.61~22.04.1

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-lowlatency-hwe-6.8<6.8.0-134.134.1~22.04.1

6.8.0-134.134.1~22.04.1

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-6.8<6.8.0-1058.61~22.04.1

6.8.0-1058.61~22.04.1

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle-6.5*

ubuntu/linux-oracle-6.8<6.8.0-1057.58~22.04.1

6.8.0-1057.58~22.04.1

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-riscv-6.8<6.8.0-134.134~22.04.1

6.8.0-134.134~22.04.1

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-realtime-6.8<6.8.1-1055.56~22.04.1

6.8.1-1055.56~22.04.1

ubuntu/linux<6.8.0-134.134

6.8.0-134.134

ubuntu/linux-aws<6.8.0-1060.63

6.8.0-1060.63

ubuntu/linux-aws-6.14*

ubuntu/linux-aws-6.17*

ubuntu/linux-azure<6.8.0-1063.71

6.8.0-1063.71

ubuntu/linux-azure-6.11*

ubuntu/linux-azure-6.14*

ubuntu/linux-azure-6.17*

ubuntu/linux-azure-fde<6.8.0-1062.69

6.8.0-1062.69

ubuntu/linux-azure-fde-6.14*

ubuntu/linux-azure-nvidia<6.8.0-1039.42

6.8.0-1039.42

ubuntu/linux-azure-nvidia-6.14*

ubuntu/linux-gcp<6.8.0-1063.69

6.8.0-1063.69

ubuntu/linux-gcp-6.11*

ubuntu/linux-gcp-6.14*

ubuntu/linux-gke<6.8.0-1058.64

6.8.0-1058.64

ubuntu/linux-gkeop<6.8.0-1045.48

6.8.0-1045.48

ubuntu/linux-hwe-6.11*

ubuntu/linux-hwe-6.14*

ubuntu/linux-hwe-6.17*

ubuntu/linux-ibm<6.8.0-1060.61

6.8.0-1060.61

ubuntu/linux-lowlatency<6.8.0-134.134.1

6.8.0-134.134.1

ubuntu/linux-lowlatency-hwe-6.11*

ubuntu/linux-nvidia<6.8.0-1058.61

6.8.0-1058.61

ubuntu/linux-nvidia-6.11*

ubuntu/linux-nvidia-6.17*

ubuntu/linux-nvidia-lowlatency<6.8.0-1058.61.1

6.8.0-1058.61.1

ubuntu/linux-nvidia-tegra<6.8.0-1029.30

6.8.0-1029.30

ubuntu/linux-oem-6.11*

ubuntu/linux-oem-6.14*

ubuntu/linux-oem-6.17*

ubuntu/linux-oem-6.8*

ubuntu/linux-oracle<6.8.0-1057.58

6.8.0-1057.58

ubuntu/linux-oracle-6.14*

ubuntu/linux-oracle-6.17*

ubuntu/linux-raspi<6.8.0-1060.64

6.8.0-1060.64

ubuntu/linux-raspi-realtime*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-6.14*

ubuntu/linux-riscv-6.17*

ubuntu/linux-xilinx<6.8.0-1032.33

6.8.0-1032.33

ubuntu/linux-bluefield<6.8.0-1026.30

6.8.0-1026.30

ubuntu/linux-raspi-realtime<6.8.0-2049.50

6.8.0-2049.50

ubuntu/linux-realtime<6.8.1-1055.56

6.8.1-1055.56

ubuntu/linux-realtime-6.14*

ubuntu/linux-realtime-6.17*

ubuntu/linux-aws-fips<6.8.0-1060.63+fips1

6.8.0-1060.63+fips1

ubuntu/linux-azure-fips<6.8.0-1062.69+fips1

6.8.0-1062.69+fips1

ubuntu/linux-fips<6.8.0-134.134+fips1

6.8.0-134.134+fips1

ubuntu/linux-gcp-fips<6.8.0-1063.69+fips1

6.8.0-1063.69+fips1

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-azure*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp*

ubuntu/linux-oracle*

ubuntu/linux-raspi*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1060.63~22.04.1
Upgrade
Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1063.71~22.04.1
Upgrade
Upgrade ubuntu/linux-azure-fde-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1062.69~22.04.1
Upgrade
Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1063.69~22.04.1
Upgrade
Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-136.136~22.04.1
Upgrade
Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1060.61~22.04.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-134.134.1~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1058.61~22.04.1
Upgrade
Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1057.58~22.04.1
Upgrade
Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-134.134~22.04.1
Upgrade
Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.1-1055.56~22.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 6.8.0-134.134
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 6.8.0-1060.63
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 6.8.0-1063.71
Upgrade
Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 6.8.0-1062.69
Upgrade
Upgrade ubuntu/linux-azure-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 6.8.0-1063.69
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 6.8.0-1058.64
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 6.8.0-1045.48
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 6.8.0-1060.61
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-134.134.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1058.61
Upgrade
Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-1058.61.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 6.8.0-1029.30
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 6.8.0-1057.58
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 6.8.0-1060.64
Upgrade
Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.
Fixed in 6.8.0-1032.33
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 6.8.0-1026.30
Upgrade
Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.
Fixed in 6.8.0-2049.50
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 6.8.1-1055.56
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1060.63+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1062.69+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-134.134+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1063.69+fips1
Compensating control
In the Linux kernel spidev driver, remove buf_lock, make spi_lock the sole lock protecting the affected operations, ensure all callers serialize access using spi_lock, and have spidev_sync() perform no locking.

Event History

May 8, 2026

CVE Published

via OSV·02:16 PM

Data Sourced

via OSV·02:16 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

Who is exposed to this issue?

Systems using the affected Ubuntu kernel packages and the spidev driver are exposed when userspace can access the same spidev file descriptor from concurrent threads.

What is required to trigger the deadlock?

A local userspace program must perform write() or read() operations and SPI_IOC_WR_MAX_SPEED_HZ ioctl() calls concurrently from separate threads on the same spidev file descriptor. The issue requires high privileges according to the supplied severity vector.

What is the impact if the issue is triggered?

The conflicting lock acquisition order can cause a real kernel-side deadlock, resulting in loss of availability. The supplied vector indicates no confidentiality or integrity impact.

How can I determine whether this is occurring?

Kernel lockdep output may report a possible circular locking dependency involving spidev_ioctl(), spidev_sync_write(), spidev->buf_lock, and spidev->spi_lock. Affected workloads may also hang while concurrently issuing spidev reads or writes and speed-setting ioctls.

UBUNTU-CVE-2026-43319: Medium severity ubuntu/linux-hwe-edge vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

Who is exposed to this issue?

What is required to trigger the deadlock?

What is the impact if the issue is triggered?

How can I determine whether this is occurring?

Company

Resources

Contact

Frequently Asked Questions

Who is exposed to this issue?

What is required to trigger the deadlock?

What is the impact if the issue is triggered?

How can I determine whether this is occurring?