LoongArch: Fix address space mismatch in kexec command line lookup

{
  "id": "c257ef6e2df9332ea6da40118823617295f29959c97facd46c9de41f56b3bf62",
  "url": "https://osv.dev/vulnerability/CVE-2026-68435",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "LoongArch: Fix address space mismatch in kexec command line lookup",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: LoongArch: Fix address space mismatch in kexec command line lookup When searching the loaded segments for the \"kexec\" command line marker, the kexec_load(2) path (file_mode == 0) passes the user-space segment buffer straight to strncmp() through a bogus (char __user *) cast. This dereferences a user pointer in kernel context, which is wrong and is flagged by sparse: arch/loongarch/kernel/machine_kexec.c:84:51: sparse: incorrect type in argument 2 (different address spaces) @@ expected char const * @@ got char [noderef] __user * Here copy the marker-sized prefix of each segment into a small on-stack buffer with copy_from_user() before comparing, and skip segments that fault. The subsequent copy_from_user() that stages the full command line into the safe area is left unchanged.",
    "evidence": "osv:CVE-2026-68435",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.1.191",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.160",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.114",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.42",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.6",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-68435",
      "aliases": [
        "CVE-2026-68435"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                  "introduced": "4a03b2ac06a5bcae29371866d9d11f5bfd4c9188"
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                {
                  "fixed": "742f2c0a64a7557495e831c3c112d92e308bd4ae"
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                {
                  "fixed": "3b71f51fa3a247921408879eab2ddee82da8a980"
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                {
                  "fixed": "eaa908d8d523b0ab75dab5ebd6662e70af5e5d7e"
                },
                {
                  "fixed": "a94d6726ec8680a2b0c453fc782a543f68a1ea06"
                },
                {
                  "fixed": "7a54e0cbaad4a5a09e7cc7a4f05d181048e98ca7"
                },
                {
                  "fixed": "485ed44db5694d8d2e5027f63ad608e705286f30"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68435.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
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                  "introduced": "6.1.0"
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              "type": "ECOSYSTEM",
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                  "introduced": "6.2.0"
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                  "fixed": "6.6.160"
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            {
              "type": "ECOSYSTEM",
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                {
                  "introduced": "6.7.0"
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                {
                  "fixed": "6.12.114"
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              "type": "ECOSYSTEM",
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                  "introduced": "6.13.0"
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            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
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                {
                  "fixed": "7.1.6"
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              ]
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          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68435.json"
          }
        }
      ],
      "modified": "2026-11-01T02:30:36.325003854Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/3b71f51fa3a247921408879eab2ddee82da8a980",
        "https://git.kernel.org/stable/c/485ed44db5694d8d2e5027f63ad608e705286f30",
        "https://git.kernel.org/stable/c/742f2c0a64a7557495e831c3c112d92e308bd4ae",
        "https://git.kernel.org/stable/c/7a54e0cbaad4a5a09e7cc7a4f05d181048e98ca7",
        "https://git.kernel.org/stable/c/a94d6726ec8680a2b0c453fc782a543f68a1ea06",
        "https://git.kernel.org/stable/c/eaa908d8d523b0ab75dab5ebd6662e70af5e5d7e",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68435.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-68435",
        "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/2026/68xxx/CVE-2026-68435.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-68435",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 489210,
  "published_at": "2026-08-12T00:07:23.359+00:00"
}