CVE-2026-31516 (GCVE-0-2026-31516)
Vulnerability from cvelistv5
Published
2026-04-22 13:54
Modified
2026-10-19 18:45
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: xfrm: prevent policy_hthresh.work from racing with netns teardown A XFRM_MSG_NEWSPDINFO request can queue the per-net work item policy_hthresh.work onto the system workqueue. The queued callback, xfrm_hash_rebuild(), retrieves the enclosing struct net via container_of(). If the net namespace is torn down before that work runs, the associated struct net may already have been freed, and xfrm_hash_rebuild() may then dereference stale memory. xfrm_policy_fini() already flushes policy_hash_work during teardown, but it does not synchronize policy_hthresh.work. Synchronize policy_hthresh.work in xfrm_policy_fini() as well, so the queued work cannot outlive the net namespace teardown and access a freed struct net.
References
Impacted products
Vendor Product Version
Linux Linux Version: 880a6fab8f6ba5b5abe59ea68533202ddea1012c
Version: 880a6fab8f6ba5b5abe59ea68533202ddea1012c
Version: 880a6fab8f6ba5b5abe59ea68533202ddea1012c
Version: 880a6fab8f6ba5b5abe59ea68533202ddea1012c
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