arm64: hibernate: mask DAIF before restoring hibernated kernel

{
  "id": "ea214405fed704c3ac9be5b0bfcfa4bca539927047b622a300b082f1412c513e",
  "url": "https://osv.dev/vulnerability/CVE-2026-93256",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "arm64: hibernate: mask DAIF before restoring hibernated kernel",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: arm64: hibernate: mask DAIF before restoring hibernated kernel The arm64 hibernate code manages the exception masking in an unsound way, leading to potential crashes and/or warnings during resume. When a hibernation image is saved in `swsusp_arch_suspend()`, all DAIF exceptions are masked (by virtue of `local_daif_save()`), and the suspended image is saved assuming that all DAIF exceptions will remain masked when the image is restored. When a hibernation image is resumed by `swsusp_arch_resume()`, only interrupts are masked (by virtue of `local_irq_disable()` in `resume_target_kernel()`). When pseudo-NMI is enabled the DAIF.IF bits will be clear, and regardless of pseudo-NMI the DAIF.DA bits will be clear. This means that there are two problems: (1) It is possible to take Debug, SError, or pseudo-NMI exceptions during the resume process. This is unsafe, as during the resume process both the old ane new kernels will tranisently be in an inconsistent state, and swsusp_arch_suspend_exit() won't retain an executable mapping of any exception vectors. Any exception taken here will be fatal and silent. (2) When re-entering the resumed kernel, some DAIF bits will be clear unexpectedly. This permits Debug, SError, or pseudo-NMI exceptions to be taken for a short period while the resumed kernel is not yet in a consistent state. This is detected by CONFIG_ARM64_DEBUG_PRIORITY_MASKING. Avoid these issues by masking all D",
    "evidence": "osv:CVE-2026-93256",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.10.270",
            "evidence": "/affected/1/ranges"
          },
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            "value": "5.15.221",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.188",
            "evidence": "/affected/1/ranges"
          },
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            "evidence": "/affected/1/ranges"
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          {
            "value": "6.12.110",
            "evidence": "/affected/1/ranges"
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          {
            "value": "6.18.52",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.2.6",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-93256",
      "aliases": [
        "CVE-2026-93256"
      ],
      "affected": [
        {
          "ranges": [
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              "type": "GIT",
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                {
                  "fixed": "099ad3edcef1d955d9f5d6aab16ae78ecdfd4cda"
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                {
                  "fixed": "716c41bd476334afb943308be9ff2142e34461b7"
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                  "fixed": "5370853041a3cb53a125b77528586278f64b378b"
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                  "fixed": "290c5b0c9fc0c61fb1c41421ed2394f955206ea0"
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                  "fixed": "012823494e20c3cce622982ebd3fd6971be39ad2"
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          }
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        {
          "ranges": [
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              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "4.7.0"
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                {
                  "fixed": "5.10.270"
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              "type": "ECOSYSTEM",
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
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          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93256.json"
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      ],
      "modified": "2026-10-28T02:30:38.511268127Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/012823494e20c3cce622982ebd3fd6971be39ad2",
        "https://git.kernel.org/stable/c/099ad3edcef1d955d9f5d6aab16ae78ecdfd4cda",
        "https://git.kernel.org/stable/c/290c5b0c9fc0c61fb1c41421ed2394f955206ea0",
        "https://git.kernel.org/stable/c/5370853041a3cb53a125b77528586278f64b378b",
        "https://git.kernel.org/stable/c/684bde100117931f4c51c644a95f42f2dab041bc",
        "https://git.kernel.org/stable/c/716c41bd476334afb943308be9ff2142e34461b7",
        "https://git.kernel.org/stable/c/c9c671e9ab87b639720db8f7f8648bdf0f3bc8ec",
        "https://git.kernel.org/stable/c/d736ace2c491623c9ab5e73744085e93e9ae3ebe",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93256.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-93256",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93256.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-93256",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 505925,
  "published_at": "2026-09-24T15:51:43.08+00:00"
}