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CVE-2026-89568

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: kho: fix size calculation in kho_preserved_memory_reserve() kho_preserved_memory_reserve() calculates the size of a preservation by doing 1 << (order + PAGE_SHIFT). Since the '1' is a 32-bit integer, it can only be shifted by 31. That is, it will only work for preservations up to 2 GiB. Larger preservations will trigger undefined behaviour. While preservations larger than 2 GiB can't be obtained via folios currently, they can be obtained via kho_preserve_pages(). For example, memblock reserve_mem uses kho_preserve_pages(). Reservations larger than 2 GiB are valid and will trigger this bug if properly aligned. Fix it by using 1UL for shifting.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-11 20:19:40.810000
Last modified
2026-10-19 09:17:52.640000
View original CVE JSON
{
  "id": "CVE-2026-89568",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:40.810",
  "lastModified": "2026-10-19T09:17:52.640",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkho: fix size calculation in kho_preserved_memory_reserve()\n\nkho_preserved_memory_reserve() calculates the size of a preservation by\ndoing 1 << (order + PAGE_SHIFT). Since the '1' is a 32-bit integer, it\ncan only be shifted by 31. That is, it will only work for preservations\nup to 2 GiB. Larger preservations will trigger undefined behaviour.\n\nWhile preservations larger than 2 GiB can't be obtained via folios\ncurrently, they can be obtained via kho_preserve_pages().\n\nFor example, memblock reserve_mem uses kho_preserve_pages().\nReservations larger than 2 GiB are valid and will trigger this bug if\nproperly aligned.\n\nFix it by using 1UL for shifting."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "kernel/liveupdate/kexec_handover.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "fc33e4b44b2717feba2f6f07ce7943a96499c9ec",
              "lessThan": "0692a8fdf0222af130c8ea97426f1c3bf3814905",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "fc33e4b44b2717feba2f6f07ce7943a96499c9ec",
              "lessThan": "42a6f03cf352eb6e6dbeef95e75e686f4cdb9bd1",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "fc33e4b44b2717feba2f6f07ce7943a96499c9ec",
              "lessThan": "3a0b8fa2eb36afc88b62a95f33f0c77c71fa5ded",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "kernel/liveupdate/kexec_handover.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.16",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.16",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.57",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0692a8fdf0222af130c8ea97426f1c3bf3814905",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3a0b8fa2eb36afc88b62a95f33f0c77c71fa5ded",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/42a6f03cf352eb6e6dbeef95e75e686f4cdb9bd1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}