sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf()

{
  "id": "f6eea421e887e76511e14227421ceed6f55615a558e199e96c5a5c64091d8c10",
  "url": "https://osv.dev/vulnerability/CVE-2024-35985",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf() It was possible to have pick_eevdf() return NULL, which then causes a NULL-deref. This turned out to be due to entity_eligible() returning falsely negative because of a s64 multiplcation overflow. Specifically, reweight_eevdf() computes the vlag without considering the limit placed upon vlag as update_entity_lag() does, and then the scaling multiplication (remember that weight is 20bit fixed point) can overflow. This then leads to the new vruntime being weird which then causes the above entity_eligible() to go side-ways and claim nothing is eligible. Thus limit the range of vlag accordingly. All this was quite rare, but fatal when it does happen.",
    "evidence": "osv:CVE-2024-35985",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.6.30",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.8.9",
            "evidence": "/affected/1/ranges"
          }
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        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2024-35985",
      "aliases": [
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            "ecosystem": "Linux"
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      ],
      "modified": "2026-10-28T02:30:27.490303495Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/06f27e6d7bf0abf54488259ef36bbf0e1fccb35c",
        "https://git.kernel.org/stable/c/1560d1f6eb6b398bddd80c16676776c0325fe5fe",
        "https://git.kernel.org/stable/c/470d347b14b0ecffa9b39cf8f644fa2351db3efb",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/35xxx/CVE-2024-35985.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2024-35985",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/35xxx/CVE-2024-35985.json"
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    "related_cves": [
      {
        "value": "CVE-2024-35985",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 493632,
  "published_at": "2024-05-20T09:47:52.389+00:00"
}