{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.113-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.2.9-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  fs/ntfs3: use d_instantiate_new() in ntfs_create_inode() and murder syzbot's \"WARNING in do_new_mount\" saga  ntfs_create_inode() creates a new inode via ntfs_new_inode(). It hashes it with insert_inode_locked() and so it's marked as I_NEW until unlock_new_inode().  ntfs 3 calls d_instantiate() in between though... Since the dentry was already hashed by the lookup before the create any path walk finds it without touching the parent's i_rwsem and so can lock the inode.  If the inode is a directory unlock_new_inode() calls lockdep_annotate_inode_mutex_key() and marks i_rwsem with the i_mutex_dir_key class.  That resets the count and the owner of a lock somebody else may already hold by now...  syzbot has been spamming us with the same godforsaken bug    \"WARNING in do_new_mount\"  since 2023. I can't take it anymore so I went looking. Afaict, syzbot's executor chdirs into a freshly mounted ntfs3 image, creates a directory and then mounts some pseudofs on it. Everytime the mkdir() takes longer than syzbot waits mount() runs concurrently:    mkdir(\"./sys\")                        mount(NULL, \"./sys\", \"sysfs\")   ntfs_create_inode()     d_instantiate()                                         user_path_at() finds the dentry                                         do_lock_mount()                                           inode_lock(inode)                                           namespace_lock()     unlock_new_inode()       lockdep_annotate_inode_mutex_key()         init_rwsem(\u0026inode-\u003ei_rwsem)                                         unlock_mount()                                           inode_unlock(inode)  The mount side then releases a lock that according to the rwsem nobody holds:    DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) \u0026\u0026 ...):   count = 0x0, magic = 0xffff888043a854e8, owner = 0x0,   curr 0xffff888000244880, list empty   WARNING: CPU: 0 PID: 5346 at kernel/locking/rwsem.c:1368 __up_write   Call Trace:    inode_unlock include/linux/fs.h:877 [inline]    unlock_mount fs/namespace.c:2892 [inline]    do_new_mount_fc fs/namespace.c:3828 [inline]    do_new_mount+0x777/0xa40 fs/namespace.c:3887  On PREEMPT_RT the same thing shows up as    DEBUG_LOCKS_WARN_ON(rt_mutex_owner(lock) != current)   WARNING: kernel/locking/rtmutex_common.h:193 at rt_mutex_slowunlock  The up_write() underflows the reset count. A following inode_lock() on that directory then never returns. A path walk into the new directory racing with the mkdir() corrupts the lock the same way via inode_lock_shared() in lookup_slow().  Switch to d_instantiate_new() and drop the trailing unlock_new_inode(). All error paths bail out before that point with I_NEW still set and keep using discard_new_inode().  May we never see this fscking bug report again.",
  "id": "DEBIAN-CVE-2026-98539",
  "modified": "2026-10-19T04:47:37.648711272Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-98539"
    }
  ],
  "upstream": [
    "CVE-2026-98539"
  ]
}