{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2021-47459",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: j1939: j1939_netdev_start(): fix UAF for rx_kref of j1939_priv\n\nIt will trigger UAF for rx_kref of j1939_priv as following.\n\n        cpu0                                    cpu1\nj1939_sk_bind(socket0, ndev0, ...)\nj1939_netdev_start\n                                        j1939_sk_bind(socket1, ndev0, ...)\n                                        j1939_netdev_start\nj1939_priv_set\n                                        j1939_priv_get_by_ndev_locked\nj1939_jsk_add\n.....\nj1939_netdev_stop\nkref_put_lock(&priv->rx_kref, ...)\n                                        kref_get(&priv->rx_kref, ...)\n                                        REFCOUNT_WARN(\"addition on 0;...\")\n\n====================================================\nrefcount_t: addition on 0; use-after-free.\nWARNING: CPU: 1 PID: 20874 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0\nRIP: 0010:refcount_warn_saturate+0x169/0x1e0\nCall Trace:\n j1939_netdev_start+0x68b/0x920\n j1939_sk_bind+0x426/0xeb0\n ? security_socket_bind+0x83/0xb0\n\nThe rx_kref's kref_get() and kref_put() should use j1939_netdev_lock to\nprotect."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "9d71dd0c7009",
                                            "version_value": "a0e47d2833b4"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.4",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "5.4",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.4.156",
                                                        "lessThanOrEqual": "5.4.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.10.76",
                                                        "lessThanOrEqual": "5.10.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.14.15",
                                                        "lessThanOrEqual": "5.14.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.15",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/a0e47d2833b4f65e6c799f28c6b636d36b8b936d",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/a0e47d2833b4f65e6c799f28c6b636d36b8b936d"
            },
            {
                "url": "https://git.kernel.org/stable/c/864e77771a24c877aaf53aee019f78619cbcd668",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/864e77771a24c877aaf53aee019f78619cbcd668"
            },
            {
                "url": "https://git.kernel.org/stable/c/6e8811707e2df0c6ba920f0cad3a3bca7b42132f",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/6e8811707e2df0c6ba920f0cad3a3bca7b42132f"
            },
            {
                "url": "https://git.kernel.org/stable/c/d9d52a3ebd284882f5562c88e55991add5d01586",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/d9d52a3ebd284882f5562c88e55991add5d01586"
            }
        ]
    },
    "generator": {
        "engine": "bippy-a5840b7849dd"
    }
}