UBUNTU-CVE-2026-90309: High severity ubuntu/linux-hwe-edge vulnerability
In the Linux kernel, the following vulnerability has been resolved: RDMA/erdma: Hold CQ references when processing EQ events EQ handlers look up CQs from dev->cqxa and invoke CQ completion or error callbacks outside the xarray lock. erdmadestroycq() can erase the CQ from the xarray and free its queue buffer and doorbell record while a previously scheduled EQ handler is still using the CQ. Add a CQ refcount and take a reference under the xarray lock with refcountincnotzero(). Remove the CQ from the xarray before dropping the destroy-path reference, then wait for in-flight EQ users before releasing CQ resources.
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
Add a CQ reference count; take a reference with refcount_inc_not_zero() while holding the xarray lock before processing EQ events. Remove the CQ from the xarray before dropping the destroy-path reference, then wait for in-flight EQ users to finish before freeing the CQ queue buffer, doorbell record, and other CQ resources.
Event History
Frequently Asked Questions
Which Ubuntu kernel package variants are identified as affected?
The affected software list includes 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.
What level of access does an attacker need?
Exploitation requires local access and low privileges. No user interaction is required.