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FKIE_CVE-2026-68455

Vulnerability from fkie_nvd - Published: 2026-08-15 06:17 - Updated: 2026-08-17 06:17
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: liveupdate: validate session type before performing operation The sessions ioctls are not applicable to all session types. PRESERVE_FD is only applicable to outgoing sessions. RETRIEVE_FD and FINISH are only valid for incoming session. Calling a incoming ioctl on an outgoing session is invalid and can cause file handlers to run into unexpected errors. For example, a user can create a (outgoing) session, preserve a memfd, and then immediately do a retrieve without doing a kexec in between. This would result in memfd's retrieve handler to run. The handlers expects to be called from a post-kexec context, and will try to do a kho_restore_vmalloc() or kho_restore_folio() to try and restore memory. KHO catches this (thanks to KHO_PAGE_MAGIC) and returns an error, but since this is considered an internal error and KHO throws out a bunch of WARN()s. Associate a type with each ioctl op and validate the type in luo_session_ioctl() before dispatching the ioctl handler to make sure the op is being called for the right session type.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3dc8a46d08a8a060d4128e9f497060b8d03c1595
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/507e3b479f9c6d85135eb5e1a77fb3fddb259ad8
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/liveupdate/luo_session.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "3dc8a46d08a8a060d4128e9f497060b8d03c1595",
              "status": "affected",
              "version": "16cec0d265219f14a7fcebcc43aeb69205adba56",
              "versionType": "git"
            },
            {
              "lessThan": "507e3b479f9c6d85135eb5e1a77fb3fddb259ad8",
              "status": "affected",
              "version": "16cec0d265219f14a7fcebcc43aeb69205adba56",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/liveupdate/luo_session.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
            {
              "lessThan": "6.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nliveupdate: validate session type before performing operation\n\nThe sessions ioctls are not applicable to all session types. PRESERVE_FD\nis only applicable to outgoing sessions. RETRIEVE_FD and FINISH are only\nvalid for incoming session. Calling a incoming ioctl on an outgoing\nsession is invalid and can cause file handlers to run into unexpected\nerrors.\n\nFor example, a user can create a (outgoing) session, preserve a memfd,\nand then immediately do a retrieve without doing a kexec in between.\nThis would result in memfd\u0027s retrieve handler to run. The handlers\nexpects to be called from a post-kexec context, and will try to do a\nkho_restore_vmalloc() or kho_restore_folio() to try and restore memory.\n\nKHO catches this (thanks to KHO_PAGE_MAGIC) and returns an error, but\nsince this is considered an internal error and KHO throws out a bunch of\nWARN()s.\n\nAssociate a type with each ioctl op and validate the type in\nluo_session_ioctl() before dispatching the ioctl handler to make sure\nthe op is being called for the right session type."
    }
  ],
  "id": "CVE-2026-68455",
  "lastModified": "2026-08-17T06:17:54.670",
  "metrics": {},
  "published": "2026-08-15T06:17:17.160",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3dc8a46d08a8a060d4128e9f497060b8d03c1595"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/507e3b479f9c6d85135eb5e1a77fb3fddb259ad8"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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