CVE-2026-89519

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: sched_ext: Replace SCX_RQ_BAL_KEEP with a dispatch verdict return SCX_RQ_BAL_KEEP tells the pick to keep running the previous task, a leftover from when balancing and picking were separate operations. An rq-level flag only works while dispatches and picks pair up one to one, which core scheduling breaks: selections interleave through dispatch's lock drops and a pick can consume a stale flag, keeping a task that has since been dequeued. Fixing core scheduling support requires the decision to travel with the dispatch that made it. Make scx_dispatch_sched() and balance_one() return an explicit verdict instead and drop the flag's plumbing from the tools autogen enum headers. Also factor the pick-side invocation, its follow-up queueing and the post-dispatch checks out of do_pick_task_scx() into dispatch_pick(). No functional changes intended. v2: Drop the SCX_RQ_BAL_KEEP plumbing from the tools autogen enum headers as well (Andrea).

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-09-11 20:19:34.533000

Last modified

2026-10-19 09:17:46.333000

View original CVE JSON

{
  "id": "CVE-2026-89519",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:34.533",
  "lastModified": "2026-10-19T09:17:46.333",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Replace SCX_RQ_BAL_KEEP with a dispatch verdict return\n\nSCX_RQ_BAL_KEEP tells the pick to keep running the previous task, a leftover\nfrom when balancing and picking were separate operations. An rq-level flag\nonly works while dispatches and picks pair up one to one, which core\nscheduling breaks: selections interleave through dispatch's lock drops and a\npick can consume a stale flag, keeping a task that has since been dequeued.\nFixing core scheduling support requires the decision to travel with the\ndispatch that made it. Make scx_dispatch_sched() and balance_one() return an\nexplicit verdict instead and drop the flag's plumbing from the tools autogen\nenum headers.\n\nAlso factor the pick-side invocation, its follow-up queueing and the\npost-dispatch checks out of do_pick_task_scx() into dispatch_pick(). No\nfunctional changes intended.\n\nv2: Drop the SCX_RQ_BAL_KEEP plumbing from the tools autogen enum headers\n    as well (Andrea)."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "kernel/sched/ext/ext.c",
            "kernel/sched/sched.h",
            "tools/sched_ext/include/scx/enum_defs.autogen.h",
            "tools/sched_ext/include/scx/enums.autogen.bpf.h",
            "tools/sched_ext/include/scx/enums.autogen.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "4c95380701f58b8112f0b891de8d160e4199e19d",
              "lessThan": "6f1d3bfe54430f8d54e0530a27f2ecbf8466576e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4c95380701f58b8112f0b891de8d160e4199e19d",
              "lessThan": "ffaab58d217581cb75353168f8812a16e10463fc",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "kernel/sched/ext/ext.c",
            "kernel/sched/sched.h",
            "tools/sched_ext/include/scx/enum_defs.autogen.h",
            "tools/sched_ext/include/scx/enums.autogen.bpf.h",
            "tools/sched_ext/include/scx/enums.autogen.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.19",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.19",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/6f1d3bfe54430f8d54e0530a27f2ecbf8466576e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ffaab58d217581cb75353168f8812a16e10463fc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}