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KVM: arm64: vgic: Fix race between LPI release and re-registration

Type: advisorySource: Official CVE List1 source record

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic: Fix race between LPI release and re-registration Fix a potential race between decrementing an LPI's reference count and evicting that structure from the LPI xarray. LPI structures are maintained in the VGIC LPI xarray (dist->lpi_xa). When the reference count of an LPI structure drops to zero, vgic_release_lpi_locked() removes the structure from the xarray and frees it under the xarray lock. However, the release of an LPI can race with a concurrent LPI re-registration with the same INTID via vgic_add_lpi() on another CPU, since the reference count drop and the xarray eviction are not performed in a single atomic step. This can happen e.g. if the guest issues a DISCARD while the LPI is still referenced from a vCPU's active-pending list (ap_list), and the same INTID is re-mapped via MAPTI. Particularly, vgic_release_lpi_locked() is called from two distinct paths: direct release via vgic_put_irq(), and deferred release via vgic_release_deleted_lpis(). During direct release, the issue can result in deleting a newly registered LPI from the xarray: CPU0 (Releasing LPI) CPU1 (Adding new LPI) ==================== ===================== vgic_put_irq() __vgic_put_irq() refcount_dec_and_test() vgic_add_lpi() xa_lock_irqsave() old_irq = xa_load(.., intid) vgic_try_get_irq_ref(old_irq) == false new IRQ inserted --> __xa_store(.., intid, ..) xa_unlock_irqrestore() xa_lock_irqsave(); vgic_release_lpi_locked(

Announced Group revision 1
Original source ↗

CVE-2026-74568

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: cve:CVE-2026-74568

Linux

Source reference: /containers/cna/affected/0/product

Affected versions
Not stated in this record
Fixed versions
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Prerequisites
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Linux

Source reference: /containers/cna/affected/1/product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a",
        "lessThan": "f8e5715a37378ea1a140ee1162fa441e149c5142",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a",
        "lessThan": "292e80a159aa88635bf668a7212cfdf526b8bd52",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a",
        "lessThan": "cbfe2b24a1ea9de35032dbdd100fdc700f5be92d",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "arch/arm64/kvm/vgic/vgic-its.c",
      "arch/arm64/kvm/vgic/vgic.c",
      "include/kvm/arm_vgic.h"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "6.17"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "6.17",
        "versionType": "semver"
      },
      {
        "status": "unaffected",
        "version": "6.18.57",
        "versionType": "semver",
        "lessThanOrEqual": "6.18.*"
      },
      {
        "status": "unaffected",
        "version": "7.1.8",
        "versionType": "semver",
        "lessThanOrEqual": "7.1.*"
      },
      {
        "status": "unaffected",
        "version": "7.2",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "arch/arm64/kvm/vgic/vgic-its.c",
      "arch/arm64/kvm/vgic/vgic.c",
      "include/kvm/arm_vgic.h"
    ],
    "defaultStatus": "affected"
  }
]
Related CVEs
CVE-2026-74568

Source reference: /cveMetadata/cveId

Publisher severity

critical

Source reference: /containers/cna/metrics

Event
#33209 · Revision 1
Added to Heist Feed
Publisher date
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