Vulnerability-Lookup

GHSA-MG62-WJ4P-3WQ4

Vulnerability from github – Published: 2026-05-27 15:33 – Updated: 2026-05-27 15:33

Details

In the Linux kernel, the following vulnerability has been resolved:

vfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex

vfio_cdx_set_msi_trigger() reads vdev->config_msi and operates on the vdev->cdx_irqs array based on its value, but provides no serialization against concurrent VFIO_DEVICE_SET_IRQS ioctls. Two callers can race such that one observes config_msi as set while another clears it and frees cdx_irqs via vfio_cdx_msi_disable(), resulting in a use-after-free of the cdx_irqs array.

Add a cdx_irqs_lock mutex to struct vfio_cdx_device and acquire it in vfio_cdx_set_msi_trigger(), which is the single chokepoint through which all updates to config_msi, cdx_irqs, and msi_count flow, covering both the ioctl path and the close-device cleanup path. This keeps the test of config_msi atomic with the subsequent enable, disable, or trigger operations.

Drop the pre-call !cdx_irqs test from vfio_cdx_irqs_cleanup() as part of this change: the optimization it provided is redundant with the !config_msi early-return inside vfio_cdx_msi_disable(), and leaving the test in place would be an unsynchronized read of state the new lock is meant to protect.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-46036"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-27T14:17:22Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex\n\nvfio_cdx_set_msi_trigger() reads vdev-\u003econfig_msi and operates on the\nvdev-\u003ecdx_irqs array based on its value, but provides no serialization\nagainst concurrent VFIO_DEVICE_SET_IRQS ioctls.  Two callers can race\nsuch that one observes config_msi as set while another clears it and\nfrees cdx_irqs via vfio_cdx_msi_disable(), resulting in a use-after-free\nof the cdx_irqs array.\n\nAdd a cdx_irqs_lock mutex to struct vfio_cdx_device and acquire it in\nvfio_cdx_set_msi_trigger(), which is the single chokepoint through\nwhich all updates to config_msi, cdx_irqs, and msi_count flow, covering\nboth the ioctl path and the close-device cleanup path.  This keeps the\ntest of config_msi atomic with the subsequent enable, disable, or\ntrigger operations.\n\nDrop the pre-call !cdx_irqs test from vfio_cdx_irqs_cleanup() as part\nof this change: the optimization it provided is redundant with the\n!config_msi early-return inside vfio_cdx_msi_disable(), and leaving the\ntest in place would be an unsynchronized read of state the new lock is\nmeant to protect.",
  "id": "GHSA-mg62-wj4p-3wq4",
  "modified": "2026-05-27T15:33:21Z",
  "published": "2026-05-27T15:33:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46036"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/670e8864b1a218d72f08db40d0103adf38fa1d9b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7530f34ec0ca1438d45a75dcb43183a1cc92eced"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7b436ade16cc81095d79b79f8efa3af0a4f5c5a2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ddf96e23c366c566283fce8377928851fa7f5e81"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-46036 (GCVE-0-2026-46036)

Vulnerability from cvelistv5 – Published: 2026-05-27 12:56 – Updated: 2026-05-27 12:56

Title

vfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex

Summary

In the Linux kernel, the following vulnerability has been resolved: vfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex vfio_cdx_set_msi_trigger() reads vdev->config_msi and operates on the vdev->cdx_irqs array based on its value, but provides no serialization against concurrent VFIO_DEVICE_SET_IRQS ioctls. Two callers can race such that one observes config_msi as set while another clears it and frees cdx_irqs via vfio_cdx_msi_disable(), resulting in a use-after-free of the cdx_irqs array. Add a cdx_irqs_lock mutex to struct vfio_cdx_device and acquire it in vfio_cdx_set_msi_trigger(), which is the single chokepoint through which all updates to config_msi, cdx_irqs, and msi_count flow, covering both the ioctl path and the close-device cleanup path. This keeps the test of config_msi atomic with the subsequent enable, disable, or trigger operations. Drop the pre-call !cdx_irqs test from vfio_cdx_irqs_cleanup() as part of this change: the optimization it provided is redundant with the !config_msi early-return inside vfio_cdx_msi_disable(), and leaving the test in place would be an unsynchronized read of state the new lock is meant to protect.

Severity

No CVSS data available.

Assigner

Linux

References

4 references

URL	Tags
https://git.kernel.org/stable/c/ddf96e23c366c5662…
https://git.kernel.org/stable/c/7b436ade16cc81095…
https://git.kernel.org/stable/c/7530f34ec0ca1438d…
https://git.kernel.org/stable/c/670e8864b1a218d72…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 848e447e000c41894ff931dc7c004fd42c8840f8 , < ddf96e23c366c566283fce8377928851fa7f5e81 (git) Affected: 848e447e000c41894ff931dc7c004fd42c8840f8 , < 7b436ade16cc81095d79b79f8efa3af0a4f5c5a2 (git) Affected: 848e447e000c41894ff931dc7c004fd42c8840f8 , < 7530f34ec0ca1438d45a75dcb43183a1cc92eced (git) Affected: 848e447e000c41894ff931dc7c004fd42c8840f8 , < 670e8864b1a218d72f08db40d0103adf38fa1d9b (git)
Linux	Linux	Affected: 6.10 Unaffected: 0 , < 6.10 (semver) Unaffected: 6.12.86 , ≤ 6.12.* (semver) Unaffected: 6.18.27 , ≤ 6.18.* (semver) Unaffected: 7.0.4 , ≤ 7.0.* (semver) Unaffected: 7.1-rc1 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/vfio/cdx/intr.c",
            "drivers/vfio/cdx/main.c",
            "drivers/vfio/cdx/private.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
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              "status": "affected",
              "version": "848e447e000c41894ff931dc7c004fd42c8840f8",
              "versionType": "git"
            },
            {
              "lessThan": "7b436ade16cc81095d79b79f8efa3af0a4f5c5a2",
              "status": "affected",
              "version": "848e447e000c41894ff931dc7c004fd42c8840f8",
              "versionType": "git"
            },
            {
              "lessThan": "7530f34ec0ca1438d45a75dcb43183a1cc92eced",
              "status": "affected",
              "version": "848e447e000c41894ff931dc7c004fd42c8840f8",
              "versionType": "git"
            },
            {
              "lessThan": "670e8864b1a218d72f08db40d0103adf38fa1d9b",
              "status": "affected",
              "version": "848e447e000c41894ff931dc7c004fd42c8840f8",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/vfio/cdx/intr.c",
            "drivers/vfio/cdx/main.c",
            "drivers/vfio/cdx/private.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.10"
            },
            {
              "lessThan": "6.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.86",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.27",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.86",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.27",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex\n\nvfio_cdx_set_msi_trigger() reads vdev-\u003econfig_msi and operates on the\nvdev-\u003ecdx_irqs array based on its value, but provides no serialization\nagainst concurrent VFIO_DEVICE_SET_IRQS ioctls.  Two callers can race\nsuch that one observes config_msi as set while another clears it and\nfrees cdx_irqs via vfio_cdx_msi_disable(), resulting in a use-after-free\nof the cdx_irqs array.\n\nAdd a cdx_irqs_lock mutex to struct vfio_cdx_device and acquire it in\nvfio_cdx_set_msi_trigger(), which is the single chokepoint through\nwhich all updates to config_msi, cdx_irqs, and msi_count flow, covering\nboth the ioctl path and the close-device cleanup path.  This keeps the\ntest of config_msi atomic with the subsequent enable, disable, or\ntrigger operations.\n\nDrop the pre-call !cdx_irqs test from vfio_cdx_irqs_cleanup() as part\nof this change: the optimization it provided is redundant with the\n!config_msi early-return inside vfio_cdx_msi_disable(), and leaving the\ntest in place would be an unsynchronized read of state the new lock is\nmeant to protect."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-27T12:56:46.381Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
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        },
        {
          "url": "https://git.kernel.org/stable/c/670e8864b1a218d72f08db40d0103adf38fa1d9b"
        }
      ],
      "title": "vfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-46036",
    "datePublished": "2026-05-27T12:56:46.381Z",
    "dateReserved": "2026-05-13T15:03:33.093Z",
    "dateUpdated": "2026-05-27T12:56:46.381Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-MG62-WJ4P-3WQ4

CVE-2026-46036 (GCVE-0-2026-46036)

Tags

Sightings

Nomenclature