CVE-2026-98561: nfp: hold IPsec RX state under the XArray lock
In the Linux kernel, the following vulnerability has been resolved:
nfp: hold IPsec RX state under the XArray lock
nfpnetipsecrx() drops the XArray lock before taking a reference to the xfrmstate it found. The delete path can erase the entry and drop the last state reference in that interval. RX can then try to increment a zero refcount after the state has been queued for destruction.
The driver queues firmware invalidation asynchronously; the delete path does not wait for the command to complete or drain pending RX processing.
The XFRM garbage collector waits for an RCU grace period before freeing the state. That delays reclamation but does not make acquiring a reference from zero valid.
Take the xfrmstate reference before releasing the XArray lock so xaerase() cannot run between lookup and reference acquisition.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.159.1-1 - Upgrade
Upgrade
azurelinux/kernelto a version that resolves this vulnerability.Fixed in 6.6.159.1-1 - 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
Event History
Frequently Asked Questions
Which systems are exposed to this race condition?
Systems using the Linux kernel's nfp driver with IPsec receive processing are exposed. The race involves an IPsec xfrm_state found through the driver's XArray during receive handling.
What conditions are needed to trigger the issue?
Receive processing must look up an IPsec state while a concurrent delete path erases that entry and drops its final reference. The vulnerable interval occurs after the XArray lock is released but before RX acquires the xfrm_state reference.
Does delayed XFRM garbage collection prevent the problem?
No. The RCU grace period delays freeing the state, but it does not make it valid for RX processing to increment a reference count that has already reached zero.
What change resolves the race?
The fix acquires the xfrm_state reference before releasing the XArray lock. This prevents the delete path from erasing the entry between state lookup and reference acquisition.