sched_ext: Preserve rq tracking across local DSQ dispatch

{
  "id": "97aba4e44488a5c463b5fedfb7c9d16be2d6cee0edd40d77d118e26b875abc0b",
  "url": "https://osv.dev/vulnerability/CVE-2026-68094",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "sched_ext: Preserve rq tracking across local DSQ dispatch",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: sched_ext: Preserve rq tracking across local DSQ dispatch dispatch_to_local_dsq() can run from scx_bpf_dsq_move_to_local() while ops.dispatch() has recorded the current rq. Moving a task to a local DSQ may switch to the source or destination rq before synchronously invoking ops.dequeue() through the following path: SCX_CALL_OP(dispatch, rq) ops.dispatch() scx_bpf_dsq_move_to_local() scx_flush_dispatch_buf() finish_dispatch() dispatch_to_local_dsq() scx_dispatch_enqueue() local_dsq_post_enq() call_task_dequeue() SCX_CALL_OP_TASK(dequeue, locked_rq, ...) The nested callback saves the recorded rq and restores it on return. If the rq tracking does not follow the lock switch, update_locked_rq() can trigger the following lockdep assertion while restoring an rq which is no longer held: WARNING: kernel/sched/sched.h:1641 at call_task_dequeue+0x160/0x170 Call Trace: scx_dispatch_enqueue+0x2b0/0x460 dispatch_to_local_dsq+0x138/0x230 scx_flush_dispatch_buf+0x1af/0x220 scx_bpf_dsq_move_to_local___v2+0xe2/0x1c0 bpf__sched_ext_ops_dispatch+0x4b/0xa7 do_pick_task_scx+0x3b6/0x910 __pick_next_task+0x105/0x1f0 __schedule+0x3e7/0x1980 Introduce switch_rq_lock() to update the tracking state together with each rq lock handoff. Use it in dispatch_to_local_dsq(), move_remote_task_to_local_dsq() and the in-balance paths of scx_dsq_move(), ensuring that scx_locked_rq() consistently refers to the rq whose lock is actually held through",
    "evidence": "osv:CVE-2026-68094",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "7.1.6",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-68094",
      "aliases": [
        "CVE-2026-68094"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "7fb39e4eb4c3db52e4707a6a1cd45362f7e803f5"
                },
                {
                  "fixed": "97c09c9f5739b8757ee29dabb0af30069137e286"
                },
                {
                  "fixed": "18d62044cda7a2b40f59d910659c0b0d6accad37"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68094.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "7.1.0"
                },
                {
                  "fixed": "7.1.6"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68094.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:24.124922348Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/18d62044cda7a2b40f59d910659c0b0d6accad37",
        "https://git.kernel.org/stable/c/97c09c9f5739b8757ee29dabb0af30069137e286",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68094.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-68094",
        "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/2026/68xxx/CVE-2026-68094.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-68094",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 490676,
  "published_at": "2026-08-10T11:58:07.086+00:00"
}