platform/x86/amd/pmc: Fix LPS0 and debugfs leaks when STB init fails

{
  "id": "b422ea2b90d0166eac55f6a1cb9e2cc6f871d94f73a69180a7a474748aa47553",
  "url": "https://osv.dev/vulnerability/CVE-2026-81015",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "platform/x86/amd/pmc: Fix LPS0 and debugfs leaks when STB init fails",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: platform/x86/amd/pmc: Fix LPS0 and debugfs leaks when STB init fails amd_pmc_probe() registers the LPS0 s2idle handler with acpi_register_lps0_dev() and creates the driver's debugfs directory before calling amd_stb_s2d_init(), which is the last step in probe that can fail. When amd_stb_s2d_init() fails (for example the S2D telemetry region cannot be ioremapped on a long-running system, or the SMU rejects the S2D setup) the error path only calls pci_dev_put() and returns. This leaves amd_pmc_s2idle_dev_ops on the global lps0_s2idle_devops_head list and leaks the debugfs directory, while the devm-managed resources backing the handler are torn down. Reloading the module then walks the corrupted list in acpi_register_lps0_dev() and hits: list_add corruption. next->prev should be prev, but was NULL. kernel BUG at lib/list_debug.c:29! acpi_register_lps0_dev+0x44/0x80 amd_pmc_probe+0x224/0x380 [amd_pmc] platform_probe+0x67/0x90 Even without a reload, the stale registration means the next s2idle transition calls into torn-down driver state. Unwind the debugfs directory and the LPS0 registration on the amd_stb_s2d_init() error path. acpi_unregister_lps0_dev() is safe to call unconditionally here: it is guarded on the same conditions as acpi_register_lps0_dev(), which is exactly what amd_pmc_remove() already relies on.",
    "evidence": "osv:CVE-2026-81015",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.18.50",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.2.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-81015",
      "aliases": [
        "CVE-2026-81015"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "49de59f69a76f538bfa5d0638a8c98d052546567"
                },
                {
                  "fixed": "d201c09c2428a4a8fd3bdcb032ae99f1e016458c"
                }
              ]
            },
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "83ad6974dd3bf34c080b3c08d36d02ebc3bd6da8"
                },
                {
                  "fixed": "bc9aa5fe21c3966c80647ed6574b94b863f23c62"
                },
                {
                  "fixed": "30e5f4d0cd0be655c800f10ae3e530391aa6c1b5"
                },
                {
                  "fixed": "76f650a76d6a36a4bee79d94db90a0e935a95477"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81015.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.14.0"
                },
                {
                  "fixed": "6.18.50"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.2.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81015.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:37.464642211Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/30e5f4d0cd0be655c800f10ae3e530391aa6c1b5",
        "https://git.kernel.org/stable/c/76f650a76d6a36a4bee79d94db90a0e935a95477",
        "https://git.kernel.org/stable/c/bc9aa5fe21c3966c80647ed6574b94b863f23c62",
        "https://git.kernel.org/stable/c/d201c09c2428a4a8fd3bdcb032ae99f1e016458c",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81015.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-81015",
        "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/2026/81xxx/CVE-2026-81015.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-81015",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 504910,
  "published_at": "2026-09-11T19:43:04.063+00:00"
}