s390/cio: fix out-of-bounds access on cio_ignore free

{
  "id": "29f676fb0184d8614b0a336f119f63db89bdf9ab9601b31d57fc8d25a2692e3e",
  "url": "https://osv.dev/vulnerability/CVE-2022-50307",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "s390/cio: fix out-of-bounds access on cio_ignore free",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: s390/cio: fix out-of-bounds access on cio_ignore free The channel-subsystem-driver scans for newly available devices whenever device-IDs are removed from the cio_ignore list using a command such as: echo free >/proc/cio_ignore Since an I/O device scan might interfer with running I/Os, commit 172da89ed0ea (\"s390/cio: avoid excessive path-verification requests\") introduced an optimization to exclude online devices from the scan. The newly added check for online devices incorrectly assumes that an I/O-subchannel's drvdata points to a struct io_subchannel_private. For devices that are bound to a non-default I/O subchannel driver, such as the vfio_ccw driver, this results in an out-of-bounds read access during each scan. Fix this by changing the scan logic to rely on a driver-independent online indication. For this we can use struct subchannel->config.ena, which is the driver's requested subchannel-enabled state. Since I/Os can only be started on enabled subchannels, this matches the intent of the original optimization of not scanning devices where I/O might be running.",
    "evidence": "osv:CVE-2022-50307",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.78",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.0.7",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2022-50307",
      "aliases": [
        "CVE-2022-50307"
      ],
      "affected": [
        {
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              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                {
                  "fixed": "0e501fd0f38e42304bfa0d46a812d93f80294a87"
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                {
                  "fixed": "106ab66cf5467726ca5ead51623043d37c06820a"
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                  "fixed": "1b6074112742f65ece71b0f299ca5a6a887d2db6"
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          ],
          "database_specific": {
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          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.15.0"
                },
                {
                  "fixed": "5.15.78"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.0.7"
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              ]
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          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-50307.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:36.040825127Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/0e501fd0f38e42304bfa0d46a812d93f80294a87",
        "https://git.kernel.org/stable/c/106ab66cf5467726ca5ead51623043d37c06820a",
        "https://git.kernel.org/stable/c/1b6074112742f65ece71b0f299ca5a6a887d2db6",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50307.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2022-50307",
        "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/2022/50xxx/CVE-2022-50307.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2022-50307",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 503156,
  "published_at": "2025-09-15T14:46:02.608+00:00"
}