CVE-2026-31516

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> xfrm: prevent policy_hthresh.work from racing with netns teardown<br /> <br /> A XFRM_MSG_NEWSPDINFO request can queue the per-net work item<br /> policy_hthresh.work onto the system workqueue.<br /> <br /> The queued callback, xfrm_hash_rebuild(), retrieves the enclosing<br /> struct net via container_of(). If the net namespace is torn down<br /> before that work runs, the associated struct net may already have<br /> been freed, and xfrm_hash_rebuild() may then dereference stale memory.<br /> <br /> xfrm_policy_fini() already flushes policy_hash_work during teardown,<br /> but it does not synchronize policy_hthresh.work.<br /> <br /> Synchronize policy_hthresh.work in xfrm_policy_fini() as well, so the<br /> queued work cannot outlive the net namespace teardown and access a<br /> freed struct net.