CVE-2026-43091

Description

In the Linux kernel, the following vulnerability has been resolved: xfrm: Wait for RCU readers during policy netns exit xfrm_policy_fini() frees the policy_bydst hash tables after flushing the policy work items and deleting all policies, but it does not wait for concurrent RCU readers to leave their read-side critical sections first. The policy_bydst tables are published via rcu_assign_pointer() and are looked up through rcu_dereference_check(), so netns teardown must also wait for an RCU grace period before freeing the table memory. Fix this by adding synchronize_rcu() before freeing the policy hash tables.

References

• https://git.kernel.org/stable/c/069daad4f2ae9c5c108131995529d5f02392c446
• https://git.kernel.org/stable/c/33a3149dd81a1e2f52b80ee1e0fc380b39f3d028
• https://git.kernel.org/stable/c/3733fce2871c9bca9dd18a1a23b1432ea215a094
• https://git.kernel.org/stable/c/438b1f668ad58f46ce699bb48e4698a7839e3f9e
• https://git.kernel.org/stable/c/b66920a3348c0f63ba18365248fa21fbf0b3a937