UBUNTU-CVE-2026-90130: Medium severity ubuntu/linux-hwe-edge vulnerability
In the Linux kernel, the following vulnerability has been resolved: vdpasim: fix cleanup after worker creation failure vdpasimcreate() leaves vdpasim->worker as an ERRPTR when kthreadrunworker() fails. The error path then drops the device reference, which releases the partially initialized simulator. vdpasimfree() unconditionally passes the worker pointer to kthreaddestroyworker(), so the ERRPTR is dereferenced and can trigger a general protection fault. Store the worker error, clear the pointer, and only clean up the worker when it was successfully initialized. Also make the release path tolerate partially initialized objects by guarding virtqueue and IOTLB cleanup, since the same release path can be reached from other initialization failures. I found this bug myself, though the patch was written with AI assistance.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42~24.04.1 - Upgrade
Upgrade
ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1~24.04.1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-42.42 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1016.17 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1016.18 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1015.16 - Upgrade
Upgrade
ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1 - Compensating control
Update the vDPA simulator release and cleanup paths to tolerate partially initialized objects: store the kthread_run_worker() error, clear vdpasim->worker, call kthread_destroy_worker() only when the worker was successfully initialized, and guard virtqueue and IOTLB cleanup.
Event History
Frequently Asked Questions
What condition is required to trigger the failure?
The failure requires creation of a vDPA simulator worker to fail after vdpasim_create() has begun initialization. In the affected error path, the worker pointer remains an ERR_PTR and is later passed to kthread_destroy_worker().
What is the practical impact if the condition is triggered?
Dereferencing the invalid worker pointer can trigger a general protection fault. The release path can also be reached from other initialization failures, which is why cleanup of virtqueue and IOTLB objects is guarded by the fix.
Which Ubuntu kernel packages are listed as affected?
The listed packages are ubuntu/linux-riscv, ubuntu/linux-realtime, ubuntu/linux-azure, ubuntu/linux-gcp, ubuntu/linux-azure-fde, ubuntu/linux-gke, ubuntu/linux-hwe-edge, and ubuntu/linux-gkeop.