{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "bf630c40164162ba1d3933c2f5e3397d083e0948"
            },
            {
              "fixed": "888363d74c3b5d32e2accf217add70f8b38e0e2b"
            },
            {
              "fixed": "9e820a6becdd955a04adbedfd767253a47eedd9e"
            },
            {
              "fixed": "1a116222acdcc1bc1a8350727ae6f28907d44594"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.15.0"
            },
            {
              "fixed": "6.18.57"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98986.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnamespace: remove the fsnotify marks of a mount namespace in process context\n\nmnt_ns_release() drops the last passive reference of a mount namespace\nand removes its fanotify marks via fsnotify_mntns_delete(). That takes\nthe mutex of every group with a mark on the namespace and the spinlock\nof the connector. Fine from process context. But mnt_ns_tree_remove()\nhands the reference the namespace was allocated with to call_rcu() and\nso the marks are removed from the RCU softirq:\n\n  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:623\n  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/3\n   __mutex_lock+0x113/0x24b0\n   fsnotify_destroy_marks+0x11b/0x3d0\n   mnt_ns_release_rcu+0x57/0xa0\n   rcu_core+0x6b6/0x1e40\n\nand lockdep complains about the connector lock being taken from softirq\ncontext. A fanotify group with a FAN_MARK_MNTNS mark on the mount\nnamespace of another task is all that's needed. Root in a user\nnamespace can do that for a mount namespace it owns. The task exits and\nthe namespace is freed with the mark still on it.\n\nRemove the marks in free_mnt_ns() before the namespace is handed to RCU.\nThat runs in process context once the last active reference is gone. A\nmark is added through a file descriptor to the namespace which holds an\nactive reference so no mark can show up after that.",
  "id": "CVE-2026-98986",
  "modified": "2026-10-28T02:30:58.771828544Z",
  "published": "2026-10-23T12:20:04.966Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1a116222acdcc1bc1a8350727ae6f28907d44594"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/888363d74c3b5d32e2accf217add70f8b38e0e2b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9e820a6becdd955a04adbedfd767253a47eedd9e"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98986.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98986"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.2",
  "summary": "namespace: remove the fsnotify marks of a mount namespace in process context"
}