UnratedFix available

md: wait for behind writes before destroying bitmap

Type: advisorySources: OSV

In the Linux kernel, the following vulnerability has been resolved: md: wait for behind writes before destroying bitmap __md_stop() destroyed the bitmap before calling mddev_detach(). That made mddev_detach() skip bitmap_ops->wait_behind_writes(), because the bitmap was already disconnected from mddev. This was still safe for the legacy bitmap because bitmap_destroy() waits for behind writes itself. llbitmap keeps that wait in its ->wait_behind_writes() operation instead, while ->destroy() tears down the llbitmap storage. With the old ordering, RAID1 behind-write completions could still run after llbitmap storage had been freed. Call mddev_detach() before md_bitmap_destroy() so the common detach path can wait for behind writes while the bitmap is still alive. Only destroy the bitmap after those users are gone.

Products: Kernel
Affected versions: Not specified
Fixed versions: 6.18.52, 7.2.6
CVEs: CVE-2026-90278
Confirmed fixed CVEs: Not specified
Updated in this feed: 8 Nov 2026, 01:38 UTC · Revision 1

Source evidence

md: wait for behind writes before destroying bitmap

core-osv · Original source

Published 17 Sept 2026, 16:08 UTC

osv:CVE-2026-90278

Kernel

Fixed versions: 6.18.52, 7.2.6

Complete source record

{
  "id": "74d78b91f2b6f9b4499f636ff0b6b40e1f8e2e6d74057ebce490eeed04766267",
  "url": "https://osv.dev/vulnerability/CVE-2026-90278",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "md: wait for behind writes before destroying bitmap",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: md: wait for behind writes before destroying bitmap __md_stop() destroyed the bitmap before calling mddev_detach(). That made mddev_detach() skip bitmap_ops->wait_behind_writes(), because the bitmap was already disconnected from mddev. This was still safe for the legacy bitmap because bitmap_destroy() waits for behind writes itself. llbitmap keeps that wait in its ->wait_behind_writes() operation instead, while ->destroy() tears down the llbitmap storage. With the old ordering, RAID1 behind-write completions could still run after llbitmap storage had been freed. Call mddev_detach() before md_bitmap_destroy() so the common detach path can wait for behind writes while the bitmap is still alive. Only destroy the bitmap after those users are gone.",
    "evidence": "osv:CVE-2026-90278",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
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            "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",
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      "aliases": [
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              "type": "ECOSYSTEM",
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                  "introduced": "6.18.0"
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            {
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                {
                  "fixed": "7.2.6"
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          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90278.json"
          }
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      ],
      "modified": "2026-10-28T02:30:52.526273615Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2a79365b2278f16e163e4024086105693b421601",
        "https://git.kernel.org/stable/c/4224dccd325a9380e8edfb66aad8bb5771c94222",
        "https://git.kernel.org/stable/c/73881ff7a75913f919a1ce9d9571bfaab8e8588d",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90278.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-90278",
        "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/2026/90xxx/CVE-2026-90278.json"
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    },
    "related_cves": [
      {
        "value": "CVE-2026-90278",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 521420,
  "published_at": "2026-09-17T16:08:09.992+00:00"
}