CVE-2026-98942 affecting package kernel 6.6.157.1-1

{
  "id": "c8134e267d0d5f9027cf163a66080bf164afd50ac790c3dc8fcba31fdbe576e3",
  "url": "https://osv.dev/vulnerability/AZL-110735",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-98942 affecting package kernel 6.6.157.1-1",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: sched_ext: Build the cid tables privately and publish them with RCU The cid tables are visible to the cid kfuncs while being modified: the first enable publishes the global pointers before filling them, ops.init_cids() overrides rewrite them in place, and re-enables rebuild them in place. A racing TRACING or SYSCALL program can read unfilled entries, including uninitialized memory in the kmalloc'd tables, or torn topo updates. Tie the tables' lifetimes to the root sched instead: each root enable builds a fresh set privately and publishes the per-table __rcu globals once the layout is final, and root disable unpublishes and RCU-frees the set. A non-NULL global is now always a fully built table which stays valid for the reader's RCU read section, and lookups stay two loads. Kfuncs treat NULL as no-mapping, also after the scheduler exits instead of reporting the stale last mapping. The cid kfuncs are available whether the root scheduler is cid-form or cpu-form, the latter to allow gradual migration to cids. Every root therefore builds and publishes a default mapping. Every reader must either be gated on scheduler liveness or NULL-check inside an RCU read section. Fix the two kfuncs that were neither: scx_bpf_this_cid() read the table with no RCU or preemption protection and scx_bpf_task_cid() relied on KF_RCU, which doesn't put a sleepable program in an RCU read section. The hotplug callbacks are instead seriali",
    "evidence": "osv:AZL-110735",
    "products": [
      {
        "name": {
          "value": "kernel",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "AZL-110735",
      "aliases": [
        "AZL-110735"
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "6.6.157.1-1"
                }
              ]
            }
          ],
          "package": {
            "name": "kernel",
            "purl": "pkg:rpm/azure-linux/kernel",
            "ecosystem": "Azure Linux:3"
          },
          "database_specific": {
            "source": "https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-110735.json"
          }
        }
      ],
      "modified": "2026-10-26T05:32:42Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-98942"
      ],
      "references": [
        "https://nvd.nist.gov/vuln/detail/CVE-2026-98942"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-98942",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 446724,
  "published_at": "2026-10-23T13:17:15+00:00"
}