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CVE-2022-4994 (GCVE-0-2022-4994)

Vulnerability from cvelistv5 – Published: 2026-07-30 09:18 – Updated: 2026-07-30 09:18
VLAI
Title
KVM: x86: wean fast IN from emulator_pio_in
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: x86: wean fast IN from emulator_pio_in Use __emulator_pio_in() directly for fast PIO instead of bouncing through emulator_pio_in() now that __emulator_pio_in() fills "val" when handling in-kernel PIO. vcpu->arch.pio.count is guaranteed to be '0', so this a pure nop. emulator_pio_in_emulated is now the last caller of emulator_pio_in. No functional change intended.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 8370c3d08bd98576d97514eca29970e03767a5d1 , < dc7a4bfde507ffe1d8bef49aba1322f1d20c2cb3 (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.10
Unaffected: 0 , < 4.10 (semver)
Unaffected: 6.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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{
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          "programFiles": [
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            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
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                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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              "operator": "OR"
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: wean fast IN from emulator_pio_in\n\nUse __emulator_pio_in() directly for fast PIO instead of bouncing through\nemulator_pio_in() now that __emulator_pio_in() fills \"val\" when handling\nin-kernel PIO.  vcpu-\u003earch.pio.count is guaranteed to be \u00270\u0027, so this a\npure nop.\n\nemulator_pio_in_emulated is now the last caller of emulator_pio_in.\n\nNo functional change intended."
        }
      ],
      "providerMetadata": {
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        "shortName": "Linux"
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          "url": "https://git.kernel.org/stable/c/dc7a4bfde507ffe1d8bef49aba1322f1d20c2cb3"
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    "cveId": "CVE-2022-4994",
    "datePublished": "2026-07-30T09:18:06.591Z",
    "dateReserved": "2026-07-30T09:16:34.860Z",
    "dateUpdated": "2026-07-30T09:18:06.591Z",
    "state": "PUBLISHED"
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      "cve": "CVE-2022-4994",
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      "title": "kernel: KVM: x86: wean fast IN from emulator_pio_in",
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      "cve": "CVE-2022-4994",
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      "title": "SUSE CVE CVE-2022-4994",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2022-4994.json",
      "version": "8"
    }
  }
}



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