Skip to content
Heist/ feed
Unrated

KVM: SEV: Forcefully invalidate SNP VMSA if its backing gmem page is zapped

Type: advisorySource: Official CVE List1 source record

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Forcefully invalidate SNP VMSA if its backing gmem page is zapped Wire up a gmem_invalidate_range() call for SNP VMs, and use it to force vCPUs to reload/recheck their guest-provided VMSA if the backing gmem page is being invalidated, e.g. is being PUNCH_HOLE'd. Use the same core logic to handle invalidations as VMX does for the APIC-access page, as the two concepts are nearly identical: shove the physical address of a page into the vCPU's control structure: 1. Snapshot the invalidation sequence counter 2. Grab the pfn (from guest_memfd in this case) 3. Acquire mmu_lock for read 4. Re-request reload if retry is needed, otherwise commit the change. Note, the re-request action in #4 is necessary as KVM's retry logic is fuzzy, i.e. can get false positives. If the guest_memfd page has been dropped, at some point a subsequent reload will fail to get a PFN from guest_memfd, and KVM will fail KVM_RUN. If the retry was due to a false positive, KVM will retry until there are no relevant MMU notifier events (and will retry in the "outer" loop, i.e. will drop locks and resched as needed). Note #2! Take care to invalidate the VMSA when a relevant memslot is DELETED or MOVED, as invalidations in response to PUNCH_HOLE are predicated on memslot bindings (KVM doesn't know what GFN range(s) to invalidate without a binding). And more importantly, the VMSA mapping requires a memslot, i.e. must be invalidated if its m

Announced Source revision 1
Original source ↗

CVE-2026-90040

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-2026-90040

Linux

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

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

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": "e366f92ea99e1961fbad5e2110900e9f4fcb249b",
        "lessThan": "ef4dee4640c6adc3051401399b0788135e77d50b",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "e366f92ea99e1961fbad5e2110900e9f4fcb249b",
        "lessThan": "2640cc26ed0dd1bf6ec2f6852a60e494093db3e5",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "e366f92ea99e1961fbad5e2110900e9f4fcb249b",
        "lessThan": "d1a3c216233413f57f5341a9b878b7e2dde7e785",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "arch/x86/include/asm/kvm-x86-ops.h",
      "arch/x86/include/asm/kvm_host.h",
      "arch/x86/kvm/mmu/mmu.c",
      "arch/x86/kvm/svm/sev.c",
      "arch/x86/kvm/svm/svm.c",
      "arch/x86/kvm/svm/svm.h",
      "arch/x86/kvm/x86.c",
      "include/linux/kvm_host.h",
      "virt/kvm/guest_memfd.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "6.11"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "6.11",
        "versionType": "semver"
      },
      {
        "status": "unaffected",
        "version": "6.18.57",
        "versionType": "semver",
        "lessThanOrEqual": "6.18.*"
      },
      {
        "status": "unaffected",
        "version": "7.2.5",
        "versionType": "semver",
        "lessThanOrEqual": "7.2.*"
      },
      {
        "status": "unaffected",
        "version": "7.3",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "arch/x86/include/asm/kvm-x86-ops.h",
      "arch/x86/include/asm/kvm_host.h",
      "arch/x86/kvm/mmu/mmu.c",
      "arch/x86/kvm/svm/sev.c",
      "arch/x86/kvm/svm/svm.c",
      "arch/x86/kvm/svm/svm.h",
      "arch/x86/kvm/x86.c",
      "include/linux/kvm_host.h",
      "virt/kvm/guest_memfd.c"
    ],
    "defaultStatus": "affected"
  }
]
Related CVEs
CVE-2026-90040

Source reference: /cveMetadata/cveId

Publisher severity

No explicit severity was provided.

Event
#36466 · Revision 1
Added to Heist Feed
Publisher date
Read the original announcement