ipvs: fix the checksum validations

{
  "id": "d91feb24654cd6dc8fc86508d0b19f444f80c9f8564c66318ea2faf673cf5e53",
  "url": "https://osv.dev/vulnerability/CVE-2026-80901",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "ipvs: fix the checksum validations",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: ipvs: fix the checksum validations ip_vs_in_icmp_v6() is missing checksum validation for ICMPv6 packets from clients. In fact, as for TCP/UDP we should validate the checksum for ICMP packets only when we mangle the packets on MASQ or on reply for tunnel. Also, Sashiko points out that handle_response_icmp() being common for IPv4 and IPv6 is missing the pseudo-header calculation while validating ICMPv6 messages from real servers which is a problem if checksum is not validated by the hardware. Fix the problems by creating ip_vs_checksum_common_check() helper and use it for TCP/UDP/ICMP both for IPv4 and IPv6. Rely on the nf_checksum() for validating the ICMP messages but use it also for TCP and UDP. Use correct IP offset for IP_VS_DBG_RL_PKT for TCP/UDP/SCTP. IPVS packets (TCP/UDP/SCTP/ICMP) do not need checksum validation on LOCAL_OUT (local clients or local real servers) and on FORWARD (traffic from servers on LAN). Do it only on LOCAL_IN, in case nf_checksum() is not called on PRE_ROUTING. Also, ip_vs_checksum_complete() can be marked static.",
    "evidence": "osv:CVE-2026-80901",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.1.183",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.151",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.103",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.44",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.8",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-80901",
      "aliases": [
        "CVE-2026-80901"
      ],
      "affected": [
        {
          "ranges": [
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              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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                  "fixed": "9cbe2c0fdb71904ee929b1851cdc1c73341a03c0"
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                {
                  "fixed": "00eb23829fd08df1b5e057cb6b625996a70e7e65"
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                {
                  "fixed": "5558a85add073215b298f3e044ff9a6d86d714ae"
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          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80901.json"
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80901.json"
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        }
      ],
      "modified": "2026-10-28T02:30:50.904550446Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/00eb23829fd08df1b5e057cb6b625996a70e7e65",
        "https://git.kernel.org/stable/c/5558a85add073215b298f3e044ff9a6d86d714ae",
        "https://git.kernel.org/stable/c/9cbe2c0fdb71904ee929b1851cdc1c73341a03c0",
        "https://git.kernel.org/stable/c/b3869d9b54e76dff64118dee4c8fd9302fcd5171",
        "https://git.kernel.org/stable/c/d418d73acf8be62744dc47359dfdde8c2148845d",
        "https://git.kernel.org/stable/c/e876b75b9020a97bbdc79721e7fc749024891c65",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80901.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-80901",
        "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/2026/80xxx/CVE-2026-80901.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-80901",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 519521,
  "published_at": "2026-09-04T17:11:15.78+00:00"
}