CVE-2026-98864 (GCVE-0-2026-98864)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:51 – Updated: 2026-10-19 09:26
VLAI
Title
sched_ext: Wait for SCX_OPSS_DISPATCHING before reenqueueing a task
Summary
In the Linux kernel, the following vulnerability has been resolved: sched_ext: Wait for SCX_OPSS_DISPATCHING before reenqueueing a task ebf1ccff79c4 ("sched_ext: Fix ops.dequeue() semantics") moved the final ops_state store in scx_dispatch_enqueue() after the DSQ unlock so that the custody update and ops.dequeue() precede it. A task can thus be found on a DSQ while still SCX_OPSS_DISPATCHING. The dequeue and core-sched pick paths wait for the state to clear in ops_dequeue() but the reenqueue paths don't. A reenqueue in that window runs ops.enqueue() and sets SCX_OPSS_QUEUED before the dispatch has completed. The dispatcher's final store then overwrites it with SCX_OPSS_NONE and finish_dispatch() drops every later dispatch of the task. Wait for SCX_OPSS_DISPATCHING to clear before dequeueing a task for reenqueue, the same way ops_dequeue() does.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6996 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: ebf1ccff79c43f860cbd2f9d6cfab9a462d0cb2d , < 43457bf6550044c40bd6d3fcdf9ea66f5a55d139 (git)
Affected: ebf1ccff79c43f860cbd2f9d6cfab9a462d0cb2d , < 7de9a6fb44eae4f05e68c805d58b9c618815adfa (git)
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Linux Linux Affected: 7.1
Unaffected: 0 , < 7.1 (semver)
Unaffected: 7.2.10 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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        }
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      "providerMetadata": {
        "dateUpdated": "2026-10-19T09:26:58.668Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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    "datePublished": "2026-10-18T15:51:25.532Z",
    "dateReserved": "2026-09-25T10:25:14.377Z",
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        ],
        "id": "CVE-2026-98864",
        "lastModified": "2026-10-19T10:19:50.473",
        "metrics": {},
        "published": "2026-10-18T16:17:40.877",
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        "vulnStatus": "Received"
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}



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