Vulnerability-Lookup

GHSA-M978-F9GM-GJ2J

Vulnerability from github – Published: 2026-05-28 12:30 – Updated: 2026-05-28 12:30

Details

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

KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()

Two bugs exist in the vCPU initialisation path:

If a check fails after hyp_pin_shared_mem() succeeds, the cleanup path jumps to 'unlock' without calling unpin_host_vcpu() or unpin_host_sve_state(), permanently leaking pin references on the host vCPU and SVE state pages.

Extract a register_hyp_vcpu() helper that performs the checks and the store. When register_hyp_vcpu() returns an error, call unpin_host_vcpu() and unpin_host_sve_state() inline before falling through to the existing 'unlock' label.

register_hyp_vcpu() publishes the new vCPU pointer into 'hyp_vm->vcpus[]' with a bare store, allowing a concurrent caller of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU object.

Ensure the store uses smp_store_release() and the load uses smp_load_acquire(). While 'vm_table_lock' currently serialises the store and the load, these barriers ensure the reader sees the fully initialised 'hyp_vcpu' object even if there were a lockless path or if the lock's own ordering guarantees were insufficient for nested object initialization.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-46147"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-28T10:16:30Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()\n\nTwo bugs exist in the vCPU initialisation path:\n\n1. If a check fails after hyp_pin_shared_mem() succeeds, the cleanup\n   path jumps to \u0027unlock\u0027 without calling unpin_host_vcpu() or\n   unpin_host_sve_state(), permanently leaking pin references on the\n   host vCPU and SVE state pages.\n\n   Extract a register_hyp_vcpu() helper that performs the checks and\n   the store. When register_hyp_vcpu() returns an error, call\n   unpin_host_vcpu() and unpin_host_sve_state() inline before falling\n   through to the existing \u0027unlock\u0027 label.\n\n2. register_hyp_vcpu() publishes the new vCPU pointer into\n   \u0027hyp_vm-\u003evcpus[]\u0027 with a bare store, allowing a concurrent caller\n   of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU\n   object.\n\n   Ensure the store uses smp_store_release() and the load uses\n   smp_load_acquire(). While \u0027vm_table_lock\u0027 currently serialises the\n   store and the load, these barriers ensure the reader sees the fully\n   initialised \u0027hyp_vcpu\u0027 object even if there were a lockless path or\n   if the lock\u0027s own ordering guarantees were insufficient for nested\n   object initialization.",
  "id": "GHSA-m978-f9gm-gj2j",
  "modified": "2026-05-28T12:30:30Z",
  "published": "2026-05-28T12:30:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46147"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6d69c0ed978f7f0efd053fc98390f25ab77c1aea"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/73b9c1e5da84cd69b1a86e374e450817cd051371"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7d3c27b54253cda91dc4d2c1bfc109c490837ab9"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-46147 (GCVE-0-2026-46147)

Vulnerability from cvelistv5 – Published: 2026-05-28 09:36 – Updated: 2026-05-28 09:36

Title

KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()

Summary

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu() Two bugs exist in the vCPU initialisation path: 1. If a check fails after hyp_pin_shared_mem() succeeds, the cleanup path jumps to 'unlock' without calling unpin_host_vcpu() or unpin_host_sve_state(), permanently leaking pin references on the host vCPU and SVE state pages. Extract a register_hyp_vcpu() helper that performs the checks and the store. When register_hyp_vcpu() returns an error, call unpin_host_vcpu() and unpin_host_sve_state() inline before falling through to the existing 'unlock' label. 2. register_hyp_vcpu() publishes the new vCPU pointer into 'hyp_vm->vcpus[]' with a bare store, allowing a concurrent caller of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU object. Ensure the store uses smp_store_release() and the load uses smp_load_acquire(). While 'vm_table_lock' currently serialises the store and the load, these barriers ensure the reader sees the fully initialised 'hyp_vcpu' object even if there were a lockless path or if the lock's own ordering guarantees were insufficient for nested object initialization.

Severity

No CVSS data available.

Assigner

Linux

References

3 references

URL	Tags
https://git.kernel.org/stable/c/7d3c27b54253cda91…
https://git.kernel.org/stable/c/6d69c0ed978f7f0ef…
https://git.kernel.org/stable/c/73b9c1e5da84cd69b…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 7d3c27b54253cda91dc4d2c1bfc109c490837ab9 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 6d69c0ed978f7f0efd053fc98390f25ab77c1aea (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 73b9c1e5da84cd69b1a86e374e450817cd051371 (git) Affected: 0 , < 6.18.30 (semver) Affected: 0 , < 7.0.7 (semver)
Linux	Linux	Unaffected: 6.18.30 , ≤ 6.18.* (semver) Unaffected: 7.0.7 , ≤ 7.0.* (semver) Unaffected: 7.1-rc2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/arm64/kvm/hyp/nvhe/pkvm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7d3c27b54253cda91dc4d2c1bfc109c490837ab9",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "6d69c0ed978f7f0efd053fc98390f25ab77c1aea",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "73b9c1e5da84cd69b1a86e374e450817cd051371",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "6.18.30",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThan": "7.0.7",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/arm64/kvm/hyp/nvhe/pkvm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.30",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1-rc2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.30",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1-rc2",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()\n\nTwo bugs exist in the vCPU initialisation path:\n\n1. If a check fails after hyp_pin_shared_mem() succeeds, the cleanup\n   path jumps to \u0027unlock\u0027 without calling unpin_host_vcpu() or\n   unpin_host_sve_state(), permanently leaking pin references on the\n   host vCPU and SVE state pages.\n\n   Extract a register_hyp_vcpu() helper that performs the checks and\n   the store. When register_hyp_vcpu() returns an error, call\n   unpin_host_vcpu() and unpin_host_sve_state() inline before falling\n   through to the existing \u0027unlock\u0027 label.\n\n2. register_hyp_vcpu() publishes the new vCPU pointer into\n   \u0027hyp_vm-\u003evcpus[]\u0027 with a bare store, allowing a concurrent caller\n   of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU\n   object.\n\n   Ensure the store uses smp_store_release() and the load uses\n   smp_load_acquire(). While \u0027vm_table_lock\u0027 currently serialises the\n   store and the load, these barriers ensure the reader sees the fully\n   initialised \u0027hyp_vcpu\u0027 object even if there were a lockless path or\n   if the lock\u0027s own ordering guarantees were insufficient for nested\n   object initialization."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-28T09:36:03.892Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/7d3c27b54253cda91dc4d2c1bfc109c490837ab9"
        },
        {
          "url": "https://git.kernel.org/stable/c/6d69c0ed978f7f0efd053fc98390f25ab77c1aea"
        },
        {
          "url": "https://git.kernel.org/stable/c/73b9c1e5da84cd69b1a86e374e450817cd051371"
        }
      ],
      "title": "KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-46147",
    "datePublished": "2026-05-28T09:36:03.892Z",
    "dateReserved": "2026-05-13T15:03:33.101Z",
    "dateUpdated": "2026-05-28T09:36:03.892Z",
    "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-M978-F9GM-GJ2J

CVE-2026-46147 (GCVE-0-2026-46147)

Tags

Sightings

Nomenclature