nilfs2: reject CLEAN_SEGMENTS ioctl with out-of-range segment numbers

{
  "id": "6c5fa8298139083b493ea2b240fe2710f910561b0b14bc92b35f45cc9218f958",
  "url": "https://osv.dev/vulnerability/CVE-2026-64359",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "nilfs2: reject CLEAN_SEGMENTS ioctl with out-of-range segment numbers",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: nilfs2: reject CLEAN_SEGMENTS ioctl with out-of-range segment numbers Syzbot reported a hung task in nilfs_transaction_begin() where multiple tasks performing chmod() on a nilfs2 mount blocked for over 143 seconds waiting to acquire ns_segctor_sem for read: INFO: task syz.0.17:5918 blocked for more than 143 seconds. Call Trace: schedule+0x164/0x360 rwsem_down_read_slowpath+0x6d9/0x940 down_read+0x99/0x2e0 nilfs_transaction_begin+0x364/0x710 fs/nilfs2/segment.c:221 nilfs_setattr+0x124/0x2c0 fs/nilfs2/inode.c:921 notify_change+0xc1a/0xf40 chmod_common+0x273/0x4a0 do_fchmodat+0x12d/0x230 The writer holding ns_segctor_sem was a concurrent NILFS_IOCTL_CLEAN_SEGMENTS caller, stuck inside printk while emitting per-element warnings from nilfs_sufile_updatev(): __nilfs_msg+0x373/0x450 fs/nilfs2/super.c:78 nilfs_sufile_updatev+0x21c/0x6d0 fs/nilfs2/sufile.c:186 nilfs_sufile_freev fs/nilfs2/sufile.h:93 [inline] nilfs_free_segments fs/nilfs2/segment.c:1140 [inline] nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1261 [inline] nilfs_segctor_do_construct+0x1f55/0x76c0 nilfs_clean_segments+0x3bd/0xa50 nilfs_ioctl_clean_segments fs/nilfs2/ioctl.c:922 [inline] nilfs_ioctl+0x261f/0x2780 The root cause is that user-supplied segment numbers are not validated before nilfs_clean_segments() begins doing work; the range check on each segnum is performed deep inside the call chain by nilfs_sufile_updatev(), which emits a nilfs_warn(",
    "evidence": "osv:CVE-2026-64359",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.10.261",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.15.212",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.178",
            "evidence": "/affected/1/ranges"
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          {
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            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.96",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.39",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-64359",
      "aliases": [
        "CVE-2026-64359"
      ],
      "affected": [
        {
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              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                {
                  "fixed": "876c98e0fc65f071680c03c2e2ee3ef7ff9ca078"
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                {
                  "fixed": "39607452b1400c7bf748f15122df4d058b768c5b"
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                  "fixed": "286f77d002a337735c0846d7480a82d9cda2aa31"
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                {
                  "fixed": "0789f0a6710713254a08f3a7d2ecbb6d1cbcf0aa"
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                  "fixed": "223463c488b0554212a94de971ea538eb2805fc7"
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                  "fixed": "d26aef771b4f6923da9f89d6d5b70d8def5853de"
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                  "fixed": "0e7a690fe435f8d5ea3feb7c1d8d73ba7e8b8aa9"
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          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64359.json"
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              "type": "ECOSYSTEM",
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                  "introduced": "2.6.31"
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                  "fixed": "5.10.261"
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          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
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            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64359.json"
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      ],
      "modified": "2026-10-28T02:30:44.696165907Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/0789f0a6710713254a08f3a7d2ecbb6d1cbcf0aa",
        "https://git.kernel.org/stable/c/0e7a690fe435f8d5ea3feb7c1d8d73ba7e8b8aa9",
        "https://git.kernel.org/stable/c/223463c488b0554212a94de971ea538eb2805fc7",
        "https://git.kernel.org/stable/c/286f77d002a337735c0846d7480a82d9cda2aa31",
        "https://git.kernel.org/stable/c/39607452b1400c7bf748f15122df4d058b768c5b",
        "https://git.kernel.org/stable/c/3ed388ec3b8922383d1e2d4432d7bd4cbbf8364e",
        "https://git.kernel.org/stable/c/876c98e0fc65f071680c03c2e2ee3ef7ff9ca078",
        "https://git.kernel.org/stable/c/d26aef771b4f6923da9f89d6d5b70d8def5853de",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64359.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-64359",
        "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/2026/64xxx/CVE-2026-64359.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-64359",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 512554,
  "published_at": "2026-07-25T08:50:15.947+00:00"
}