github - ghsa-2948-3mj2-4gw2

GHSA-2948-3MJ2-4GW2

Vulnerability from github – Published: 2024-03-01 00:30 – Updated: 2024-12-10 18:31

Details

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

KVM: SVM: Use online_vcpus, not created_vcpus, to iterate over vCPUs

Use the kvm_for_each_vcpu() helper to iterate over vCPUs when encrypting VMSAs for SEV, which effectively switches to use online_vcpus instead of created_vcpus. This fixes a possible null-pointer dereference as created_vcpus does not guarantee a vCPU exists, since it is updated at the very beginning of KVM_CREATE_VCPU. created_vcpus exists to allow the bulk of vCPU creation to run in parallel, while still correctly restricting the max number of max vCPUs.

Severity ?

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47062"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
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    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-02-29T23:15:07Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SVM: Use online_vcpus, not created_vcpus, to iterate over vCPUs\n\nUse the kvm_for_each_vcpu() helper to iterate over vCPUs when encrypting\nVMSAs for SEV, which effectively switches to use online_vcpus instead of\ncreated_vcpus.  This fixes a possible null-pointer dereference as\ncreated_vcpus does not guarantee a vCPU exists, since it is updated at\nthe very beginning of KVM_CREATE_VCPU.  created_vcpus exists to allow the\nbulk of vCPU creation to run in parallel, while still correctly\nrestricting the max number of max vCPUs.",
  "id": "GHSA-2948-3mj2-4gw2",
  "modified": "2024-12-10T18:31:06Z",
  "published": "2024-03-01T00:30:28Z",
  "references": [
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      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47062"
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      "url": "https://git.kernel.org/stable/c/bd0cced2ae93195668f983d443f7f17e8efd24d2"
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  "severity": [
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      "type": "CVSS_V3"
    }
  ]
}

CVE-2021-47062 (GCVE-0-2021-47062)

Vulnerability from cvelistv5 – Published: 2024-02-29 22:37 – Updated: 2025-05-04 07:03

Summary

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Use online_vcpus, not created_vcpus, to iterate over vCPUs Use the kvm_for_each_vcpu() helper to iterate over vCPUs when encrypting VMSAs for SEV, which effectively switches to use online_vcpus instead of created_vcpus. This fixes a possible null-pointer dereference as created_vcpus does not guarantee a vCPU exists, since it is updated at the very beginning of KVM_CREATE_VCPU. created_vcpus exists to allow the bulk of vCPU creation to run in parallel, while still correctly restricting the max number of max vCPUs.

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/bd0cced2ae9319566…
	https://git.kernel.org/stable/c/ba7bf5d6336aa9c0d…
	https://git.kernel.org/stable/c/c36b16d29f3af5f32…

Impacted products

Vendor

Product

Version

Linux

Affected: ad73109ae7ec30d5bfb76be108e304f9f0af4829 , < bd0cced2ae93195668f983d443f7f17e8efd24d2 (git)
Affected: ad73109ae7ec30d5bfb76be108e304f9f0af4829 , < ba7bf5d6336aa9c0d977b161bfa420c56d46ee40 (git)
Affected: ad73109ae7ec30d5bfb76be108e304f9f0af4829 , < c36b16d29f3af5f32fc1b2a3401bf48f71cabee1 (git)

Linux

Affected: 5.11
Unaffected: 0 , < 5.11 (semver)
Unaffected: 5.11.21 , ≤ 5.11.* (semver)
Unaffected: 5.12.4 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)

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Sightings

Author	Source	Type	Date

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-2948-3MJ2-4GW2

CVE-2021-47062 (GCVE-0-2021-47062)

Tags

Sightings

Nomenclature