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  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31577.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnilfs2: fix NULL i_assoc_inode dereference in nilfs_mdt_save_to_shadow_map\n\nThe DAT inode's btree node cache (i_assoc_inode) is initialized lazily\nduring btree operations. However, nilfs_mdt_save_to_shadow_map()\nassumes i_assoc_inode is already initialized when copying dirty pages\nto the shadow map during GC.\n\nIf NILFS_IOCTL_CLEAN_SEGMENTS is called immediately after mount before\nany btree operation has occurred on the DAT inode, i_assoc_inode is\nNULL leading to a general protection fault.\n\nFix this by calling nilfs_attach_btree_node_cache() on the DAT inode\nin nilfs_dat_read() at mount time, ensuring i_assoc_inode is always\ninitialized before any GC operation can use it.",
  "id": "CVE-2026-31577",
  "modified": "2026-07-15T01:49:12.656022825Z",
  "published": "2026-04-24T14:42:08.879Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/41de342278ae025c99cc8d33648773f05e306cf1"
    },
    {
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      "url": "https://git.kernel.org/stable/c/449ec5fc99f45974525ba9eea16b6670c45cd363"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4a4e0328edd9e9755843787d28f16dd4165f8b48"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6637bbcfb59df5b732a79e5ab1a74886a0b93d59"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7318e3549518ce8f14776a489d86488d80d7e2c8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7902b1df1520a0880bcda7a3704cfacd17905a83"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/837c7a59fb58f81b0db33848357f6a5d0d1250ad"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/97fb7afec404912d967a7d4715f37742666b3084"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c36e206f302f1ddefed92d09ecbba070e1ae079e"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31577.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31577"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "nilfs2: fix NULL i_assoc_inode dereference in nilfs_mdt_save_to_shadow_map"
}