ksmbd: safely discard unregistered deferred locks

{
  "id": "d4b4844bf7f53832cc8745505746abc6ccf37f08246e7d4e7acebb1d827a7d26",
  "url": "https://osv.dev/vulnerability/CVE-2026-90156",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "ksmbd: safely discard unregistered deferred locks",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: ksmbd: safely discard unregistered deferred locks When vfs_lock_file() defers a lock, smb2_lock() puts its ksmbd_lock on rollback_list before allocating and registering the asynchronous work. If either operation fails, rollback assumes that smb_lock->conn is initialized and dereferences NULL. The deferred file_lock also remains linked into the VFS blocked-lock state while it is freed. Keep the lock off rollback_list until async setup succeeds. On setup failures, explicitly unblock and wake the deferred lock before freeing it and its ksmbd wrapper.",
    "evidence": "osv:CVE-2026-90156",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.1.191",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.160",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.114",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.57",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.2.6",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-90156",
      "aliases": [
        "CVE-2026-90156"
      ],
      "affected": [
        {
          "ranges": [
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              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
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                  "fixed": "aaa51ac0d934cb4e2ab96e150fccc934e822009b"
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                {
                  "fixed": "ecdcfa15b3d799476c685cecd433ebefc93015c8"
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                {
                  "fixed": "77413400f083a959724de6f36348c9677ef9873a"
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                {
                  "fixed": "52b91bc5253bb83665f3ea70565d0b2487dae643"
                },
                {
                  "fixed": "d09af9a35ff7b77a950b507133d9092aadbfeff4"
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                {
                  "fixed": "054bcca4cd9f00719b01f7108b51a2168fb94f15"
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              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90156.json"
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        {
          "ranges": [
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              "type": "ECOSYSTEM",
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                  "introduced": "5.15.0"
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                  "fixed": "6.1.191"
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              "type": "ECOSYSTEM",
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                  "introduced": "6.2.0"
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                  "introduced": "6.7.0"
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90156.json"
          }
        }
      ],
      "modified": "2026-11-01T02:30:50.954192447Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/054bcca4cd9f00719b01f7108b51a2168fb94f15",
        "https://git.kernel.org/stable/c/52b91bc5253bb83665f3ea70565d0b2487dae643",
        "https://git.kernel.org/stable/c/77413400f083a959724de6f36348c9677ef9873a",
        "https://git.kernel.org/stable/c/aaa51ac0d934cb4e2ab96e150fccc934e822009b",
        "https://git.kernel.org/stable/c/d09af9a35ff7b77a950b507133d9092aadbfeff4",
        "https://git.kernel.org/stable/c/ecdcfa15b3d799476c685cecd433ebefc93015c8",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90156.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-90156",
        "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/2026/90xxx/CVE-2026-90156.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-90156",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 488322,
  "published_at": "2026-09-17T16:06:48.393+00:00"
}