nilfs2: fix BUG in nilfs_copy_dirty_pages() on dirty state mismatch

{
  "id": "7fe6a9a84c8fefe64ee5b4ea82562637a1d3af7ba5c01a5040a1ecb523011c50",
  "url": "https://osv.dev/vulnerability/CVE-2026-90418",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "nilfs2: fix BUG in nilfs_copy_dirty_pages() on dirty state mismatch",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix BUG in nilfs_copy_dirty_pages() on dirty state mismatch Syzbot reported a kernel BUG triggered within nilfs_copy_dirty_pages(), which copies dirty DAT file folios/pages to its shadow page cache. The BUG occurs when a retrieved dirty folio/page unexpectedly loses its 'dirty' status. This issue arises because, since the commit referenced below, the 'dirty' flag of a folio/page can be cleared asynchronously after the filesystem detects metadata corruption and transitions to read-only mode. Resolve the issue by returning an -EROFS error if the filesystem has transitioned to read-only mode. Also change the behavior to issue a kernel warning only once instead of triggering a kernel BUG when this unexpected 'dirty' state is detected while the filesystem is not in read-only mode.",
    "evidence": "osv:CVE-2026-90418",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.1.191",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.157",
            "evidence": "/affected/1/ranges"
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          {
            "value": "6.12.110",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.52",
            "evidence": "/affected/1/ranges"
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          {
            "value": "7.2.6",
            "evidence": "/affected/1/ranges"
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    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-90418",
      "aliases": [
        "CVE-2026-90418"
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      "affected": [
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
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          "database_specific": {
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      ],
      "modified": "2026-11-01T02:30:24.881030602Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/3904fb0ee741ebbbc27ec8f50a9bb6cd31e8af05",
        "https://git.kernel.org/stable/c/4e1f21e7540b25d83f86b50780836ed7d2afcc93",
        "https://git.kernel.org/stable/c/5166a21b12f549774f2983fa86d2526ea9e66ace",
        "https://git.kernel.org/stable/c/66f4ad3ce158902e5f98afea93189972ed8750c2",
        "https://git.kernel.org/stable/c/6879c603a8d07af82da83768cc2342a11bd444e5",
        "https://git.kernel.org/stable/c/f181155baf0c93a74ebe804c6cecbe970e78ee9e",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90418.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-90418",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
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    "related_cves": [
      {
        "value": "CVE-2026-90418",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 498780,
  "published_at": "2026-09-17T16:09:43.223+00:00"
}