accel/ethosu: fix IFM region index out-of-bounds in command stream parser

{
  "id": "79cd61d40d2a9235ef5a822931dd4a08cb2020a8539b39a1c461d52f8b1f08c0",
  "url": "https://osv.dev/vulnerability/CVE-2026-53172",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "accel/ethosu: fix IFM region index out-of-bounds in command stream parser",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: accel/ethosu: fix IFM region index out-of-bounds in command stream parser NPU_SET_IFM_REGION extracts the region index with param & 0x7f, giving a maximum value of 127. However region_size[] and output_region[] in struct ethosu_validated_cmdstream_info are both sized to NPU_BASEP_REGION_MAX (8), giving valid indices [0..7]. Every other region assignment in the same switch uses param & 0x7: NPU_SET_OFM_REGION: st.ofm.region = param & 0x7; NPU_SET_IFM2_REGION: st.ifm2.region = param & 0x7; NPU_SET_WEIGHT_REGION: st.weight[0].region = param & 0x7; NPU_SET_SCALE_REGION: st.scale[0].region = param & 0x7; The 0x7f mask on IFM is inconsistent and appears to be a typo. feat_matrix_length() and calc_sizes() use the region index directly as an array subscript into the kzalloc'd info struct: info->region_size[fm->region] = max(...); A userspace caller supplying NPU_SET_IFM_REGION with param > 7 causes a write up to 127*8 = 1016 bytes past the start of region_size[], corrupting adjacent kernel heap data. Fix by applying the same & 0x7 mask used by all other region assignments.",
    "evidence": "osv:CVE-2026-53172",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "7.0.13",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-53172",
      "aliases": [
        "CVE-2026-53172"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "5a5e9c0228e613f0ef2a58b9782d7c0ea8f1e58b"
                },
                {
                  "fixed": "ee7bed779def61ebff1b92b0e851f412176fa416"
                },
                {
                  "fixed": "00f547e0dfecf83014fb32bcba587c6b684c1362"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53172.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.0.13"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53172.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:37.866727438Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/00f547e0dfecf83014fb32bcba587c6b684c1362",
        "https://git.kernel.org/stable/c/ee7bed779def61ebff1b92b0e851f412176fa416",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53172.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-53172",
        "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/2026/53xxx/CVE-2026-53172.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-53172",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 505008,
  "published_at": "2026-06-25T08:38:50.056+00:00"
}