mm/damon/core: disallow non-power of two min_region_sz on damon_start()

{
  "id": "fd88e7b26b16cfc9e77b8a1bbcc5d28af99b4b0a444f86a9cf2d74c68e8f45a1",
  "url": "https://osv.dev/vulnerability/CVE-2026-52905",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "mm/damon/core: disallow non-power of two min_region_sz on damon_start()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: mm/damon/core: disallow non-power of two min_region_sz on damon_start() Commit d8f867fa0825 (\"mm/damon: add damon_ctx->min_sz_region\") introduced a bug that allows unaligned DAMON region address ranges. Commit c80f46ac228b (\"mm/damon/core: disallow non-power of two min_region_sz\") fixed it, but only for damon_commit_ctx() use case. Still, DAMON sysfs interface can emit non-power of two min_region_sz via damon_start(). Fix the path by adding the is_power_of_2() check on damon_start(). The issue was discovered by sashiko [1].",
    "evidence": "osv:CVE-2026-52905",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.18.30",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.0.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-52905",
      "aliases": [
        "CVE-2026-52905"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "d8f867fa0825fb3e358457566d7326d8aab2406a"
                },
                {
                  "fixed": "1de2db19a6028abe7d905875922faef5b873de67"
                },
                {
                  "fixed": "89b6226b6c2a4add3939f361653a47c212d6ab75"
                },
                {
                  "fixed": "95093e5cb4c5b50a5b1a4b79f2942b62744bd66a"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52905.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.18.0"
                },
                {
                  "fixed": "6.18.30"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.0.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52905.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:51.531703705Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1de2db19a6028abe7d905875922faef5b873de67",
        "https://git.kernel.org/stable/c/89b6226b6c2a4add3939f361653a47c212d6ab75",
        "https://git.kernel.org/stable/c/95093e5cb4c5b50a5b1a4b79f2942b62744bd66a",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52905.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-52905",
        "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/2026/52xxx/CVE-2026-52905.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-52905",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 520146,
  "published_at": "2026-06-09T12:36:02.516+00:00"
}