dpll: fix NULL deref in dpll_device_ops() during teardown race

{
  "id": "056e5474579f44ac43c265388b46bcc91433a5cc2cec3aedd2c3d4effd9a1ba4",
  "url": "https://osv.dev/vulnerability/CVE-2026-90144",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "dpll: fix NULL deref in dpll_device_ops() during teardown race",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: dpll: fix NULL deref in dpll_device_ops() during teardown race When the last owner of a dpll device unregisters while a foreign driver still holds a pin on it via dpll_pin_on_pin_register(), the dpll object stays alive with an empty registration list. A pin notification queued before the unregister (e.g. ice reacting to zl3073x_i2c removal) then walks pin->dpll_refs into dpll_device_ops(), which trips the WARN_ON and dereferences the missing registration. dpll_lock cannot help because the notification work was queued before the unregistering driver took the lock. Treat the empty registration list as a legitimate transient state. Make dpll_priv() and dpll_device_ops() return NULL in that case and make every pin netlink path that resolves a device from a pin skip such dplls. dpll_cmd_pin_get_one() picks a ref with a live registration and returns -ENODEV when there is none, the pin dumpit skips such a pin instead of aborting the dump, dpll_msg_add_pin_dplls() and the frequency, esync, reference sync and phase adjust set paths skip dead refs, and dpll_pin_parent_device_set() validates the parent with dpll_device_get_by_id(). dpll_pin_register() is the last caller that dereferenced the device ops without a check, so move its frequency monitor validation under dpll_lock and tolerate a missing registration there as well. The empty registration list is equivalent to a cleared DPLL_REGISTERED mark, both transitions ha",
    "evidence": "osv:CVE-2026-90144",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "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-2026-90144",
      "aliases": [
        "CVE-2026-90144"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "9431063ad323ac864750aeba4d304389bc42ca4e"
                },
                {
                  "fixed": "7d9661d6ef60bee705a3bb220dc59f10d9155c31"
                },
                {
                  "fixed": "d39da3ff8d39c31761bf1698bc02a5a206722136"
                },
                {
                  "fixed": "fdbf04e3e01a872d0ef2149f846f1a3e3cb54f5b"
                },
                {
                  "fixed": "33f016b23a219fe034213849b51436b8e79df251"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90144.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.114"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.57"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.2.6"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90144.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:28.026713865Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/33f016b23a219fe034213849b51436b8e79df251",
        "https://git.kernel.org/stable/c/7d9661d6ef60bee705a3bb220dc59f10d9155c31",
        "https://git.kernel.org/stable/c/d39da3ff8d39c31761bf1698bc02a5a206722136",
        "https://git.kernel.org/stable/c/fdbf04e3e01a872d0ef2149f846f1a3e3cb54f5b",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90144.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-90144",
        "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-2026-90144.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-90144",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 494874,
  "published_at": "2026-09-17T16:06:40.413+00:00"
}