CVE-2026-43091 (GCVE-0-2026-43091)

Vulnerability from cvelistv5 – Published: 2026-05-06 07:40 – Updated: 2026-05-06 07:40
VLAI?
Title
xfrm: Wait for RCU readers during policy netns exit
Summary
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.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < b66920a3348c0f63ba18365248fa21fbf0b3a937 (git)
Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 438b1f668ad58f46ce699bb48e4698a7839e3f9e (git)
Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 3733fce2871c9bca9dd18a1a23b1432ea215a094 (git)
Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 33a3149dd81a1e2f52b80ee1e0fc380b39f3d028 (git)
Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 069daad4f2ae9c5c108131995529d5f02392c446 (git)
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    Linux Linux Affected: 4.9
Unaffected: 0 , < 4.9 (semver)
Unaffected: 6.6.136 , ≤ 6.6.* (semver)
Unaffected: 6.12.83 , ≤ 6.12.* (semver)
Unaffected: 6.18.24 , ≤ 6.18.* (semver)
Unaffected: 6.19.14 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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{
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          "programFiles": [
            "net/xfrm/xfrm_policy.c"
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: Wait for RCU readers during policy netns exit\n\nxfrm_policy_fini() frees the policy_bydst hash tables after flushing the\npolicy work items and deleting all policies, but it does not wait for\nconcurrent RCU readers to leave their read-side critical sections first.\n\nThe policy_bydst tables are published via rcu_assign_pointer() and are\nlooked up through rcu_dereference_check(), so netns teardown must also\nwait for an RCU grace period before freeing the table memory.\n\nFix this by adding synchronize_rcu() before freeing the policy hash tables."
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      "providerMetadata": {
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        "shortName": "Linux"
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      "title": "xfrm: Wait for RCU readers during policy netns exit",
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    "cveId": "CVE-2026-43091",
    "datePublished": "2026-05-06T07:40:23.955Z",
    "dateReserved": "2026-05-01T14:12:55.984Z",
    "dateUpdated": "2026-05-06T07:40:23.955Z",
    "state": "PUBLISHED"
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  }
}


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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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