bpf: Preserve inner map identity in callback frames

{
  "id": "9429599fbfe98109461807ddf9ebc8be2c0683ac922d57d1814278efde54450a",
  "url": "https://osv.dev/vulnerability/CVE-2026-98033",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "bpf: Preserve inner map identity in callback frames",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: bpf: Preserve inner map identity in callback frames Callback frame constructors initialize map-typed argument registers with __mark_reg_known_zero() and then restore map_ptr. This clears map_uid, which is the only field distinguishing inner maps that share an inner_map_meta template. When a timer callback invokes bpf_for_each_map_elem() on a second inner map, both the saved first map and the second map value can reach the nested callback as the same template with map_uid zero. bpf_timer_init() then accepts pairing the timer from the second map with the first map. The runtime records the first map in the timer without taking a reference. Freeing that map does not find the timer stored in the second map, so a later timer callback dereferences the freed map. Copy map_uid from the same caller register as map_ptr when constructing for-each, timer/workqueue, and task-work callback arguments. The existing identity check can then reject mismatched inner maps while allowing a callback value to be paired with its actual map.",
    "evidence": "osv:CVE-2026-98033",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.6.160",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.114",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.57",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.2.7",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-98033",
      "aliases": [
        "CVE-2026-98033"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "69c087ba6225b574afb6e505b72cb75242a3d844"
                },
                {
                  "fixed": "cf85e4f94d7feef8b3c4c90dbe2468595a48393b"
                },
                {
                  "fixed": "166221c52d3ca332f8699a854efca8e2704bb137"
                },
                {
                  "fixed": "08b534bafdd9de65b6374474a8fe719c90eb3b01"
                },
                {
                  "fixed": "66ff2eff093d2a0838f39c713eeb590bc0946c2a"
                },
                {
                  "fixed": "b90c5d770dad910fb89e6c1b15052a8a1e8db752"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98033.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.13.0"
                },
                {
                  "fixed": "6.6.160"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.114"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.57"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.2.7"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98033.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:24.871528725Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/08b534bafdd9de65b6374474a8fe719c90eb3b01",
        "https://git.kernel.org/stable/c/166221c52d3ca332f8699a854efca8e2704bb137",
        "https://git.kernel.org/stable/c/66ff2eff093d2a0838f39c713eeb590bc0946c2a",
        "https://git.kernel.org/stable/c/b90c5d770dad910fb89e6c1b15052a8a1e8db752",
        "https://git.kernel.org/stable/c/cf85e4f94d7feef8b3c4c90dbe2468595a48393b",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98033.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-98033",
        "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-2026-98033.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-98033",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 491601,
  "published_at": "2026-09-25T10:23:48.761+00:00"
}