Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: xfrm: avoid lock inversion in nat keepalive work nat_keepalive_work() walks the state table while xfrm_state_walk() holds net->xfrm.xfrm_state_lock. Its callback then acquires x->lock, which conflicts with the delete path taking the same locks in reverse order via xfrm_state_delete() and __xfrm_state_delete(). This creates an AB-BA deadlock that is reported by lockdep when a NAT keepalive worker races with SA deletion. Fix this by splitting the keepalive walk into two phases. First, collect the candidate states while the walk holds xfrm_state_lock and take a reference on each state. Then, after the walk completes, process each collected state and acquire x->lock without nesting it under xfrm_state_lock.
References
- https://git.kernel.org/stable/c/5c86c895d1cac81a71ead3005084c6265cf6a7a5
- https://git.kernel.org/stable/c/763fe700b7c58ad64fe5202c5638848244dd4127
- https://git.kernel.org/stable/c/89ef3a2e1e4682ab82b0455ce113f8c39fb9e50d
- https://git.kernel.org/stable/c/a9fa05b7a1246797748d15771052639e0d3cabf1
- https://git.kernel.org/stable/c/ea09210462316e5235a25eccb11ad0708d86615e
FAQ
What is CVE-2026-80845?
CVE-2026-80845 is a documented vulnerability. In the Linux kernel, the following vulnerability has been resolved: xfrm: avoid lock inversion in nat keepalive work nat_keepalive_work() walks the state table while xfrm_state_walk() holds net->xfr...
How severe is CVE-2026-80845?
CVSS scoring is not yet available for CVE-2026-80845. Check NVD for updates.
Is there a patch for CVE-2026-80845?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.