dpaa2-switch: validate num_ifs to prevent out-of-bounds write

{
  "id": "9541483dc90e3e977cacda510b6ed3eb3ee86bd2d111e12725c97798c113cd93",
  "url": "https://osv.dev/vulnerability/CVE-2026-43205",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "dpaa2-switch: validate num_ifs to prevent out-of-bounds write",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: dpaa2-switch: validate num_ifs to prevent out-of-bounds write The driver obtains sw_attr.num_ifs from firmware via dpsw_get_attributes() but never validates it against DPSW_MAX_IF (64). This value controls iteration in dpaa2_switch_fdb_get_flood_cfg(), which writes port indices into the fixed-size cfg->if_id[DPSW_MAX_IF] array. When firmware reports num_ifs >= 64, the loop can write past the array bounds. Add a bound check for num_ifs in dpaa2_switch_init(). dpaa2_switch_fdb_get_flood_cfg() appends the control interface (port num_ifs) after all matched ports. When num_ifs == DPSW_MAX_IF and all ports match the flood filter, the loop fills all 64 slots and the control interface write overflows by one entry. The check uses >= because num_ifs == DPSW_MAX_IF is also functionally broken. build_if_id_bitmap() silently drops any ID >= 64: if (id[i] < DPSW_MAX_IF) bmap[id[i] / 64] |= ...",
    "evidence": "osv:CVE-2026-43205",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.202",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.165",
            "evidence": "/affected/1/ranges"
          },
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            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.75",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.16",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.19.6",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-43205",
      "aliases": [
        "CVE-2026-43205"
      ],
      "affected": [
        {
          "ranges": [
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              "type": "GIT",
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                  "fixed": "a26dda3bae469c8e4e1b1993ad33dafa32d0fc28"
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                {
                  "fixed": "a3034a8d56174dd6464c46823438f25797910a8d"
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                {
                  "fixed": "b690635d4719214892855b79ce018d4b1672ac96"
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                {
                  "fixed": "8b841fd529db9faf8bc678d429d4bf4e98b10900"
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                {
                  "fixed": "89764cf44544e943230f5e03b8c40a90da26537c"
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                {
                  "fixed": "c18493f750208eb4ff1198fc5a02786b8b2d70a6"
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                {
                  "fixed": "8a5752c6dcc085a3bfc78589925182e4e98468c5"
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              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-43205.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
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                  "introduced": "5.13.0"
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                  "introduced": "5.16.0"
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                  "introduced": "6.2.0"
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            {
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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-2026-43205.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:34.067881720Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/89764cf44544e943230f5e03b8c40a90da26537c",
        "https://git.kernel.org/stable/c/8a5752c6dcc085a3bfc78589925182e4e98468c5",
        "https://git.kernel.org/stable/c/8b841fd529db9faf8bc678d429d4bf4e98b10900",
        "https://git.kernel.org/stable/c/a26dda3bae469c8e4e1b1993ad33dafa32d0fc28",
        "https://git.kernel.org/stable/c/a3034a8d56174dd6464c46823438f25797910a8d",
        "https://git.kernel.org/stable/c/b690635d4719214892855b79ce018d4b1672ac96",
        "https://git.kernel.org/stable/c/c18493f750208eb4ff1198fc5a02786b8b2d70a6",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43205.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-43205",
        "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/2026/43xxx/CVE-2026-43205.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-43205",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 501215,
  "published_at": "2026-05-06T11:28:10.27+00:00"
}