drm/amdgpu: Skip KFD mapping clear before initialization

{
  "id": "c00c5029b192b5167357ff3838299649dcd4fa16f96d822e9cd0900c68403267",
  "url": "https://osv.dev/vulnerability/CVE-2026-98178",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "drm/amdgpu: Skip KFD mapping clear before initialization",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Skip KFD mapping clear before initialization amdgpu_amdkfd_clear_kfd_mapping() assumes that a non-NULL kfd_dev has a fully populated node array. This is not true when KFD device initialization fails after probe. For example, kgd2kfd_device_init() sets num_nodes before checking PCIe atomics support. On Polaris systems without the required atomics, it returns before allocating nodes[0], but the kfd_dev remains attached to the amdgpu device. A later GPU reset then dereferences nodes[0]->id. Require the authoritative KFD initialization flag before walking the node array, matching the existing KFD reset and teardown paths. (cherry picked from commit 4ac1835823c47903fbb278bbf474773c46f59edc)",
    "evidence": "osv:CVE-2026-98178",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "7.2.8",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-98178",
      "aliases": [
        "CVE-2026-98178"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                {
                  "fixed": "157d3f1db7e7e6f320daa221fae84a4c13555b6f"
                },
                {
                  "fixed": "7f9caa70aef0950e06d395ca0035831214d88187"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98178.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "7.2.0"
                },
                {
                  "fixed": "7.2.8"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98178.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:38.045194082Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/157d3f1db7e7e6f320daa221fae84a4c13555b6f",
        "https://git.kernel.org/stable/c/7f9caa70aef0950e06d395ca0035831214d88187",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98178.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-98178",
        "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/2026/98xxx/CVE-2026-98178.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-98178",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 505472,
  "published_at": "2026-10-06T08:44:21.602+00:00"
}