{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-36478",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnull_blk: fix null-ptr-dereference while configuring 'power' and 'submit_queues'\n\nWriting 'power' and 'submit_queues' concurrently will trigger kernel\npanic:\n\nTest script:\n\nmodprobe null_blk nr_devices=0\nmkdir -p /sys/kernel/config/nullb/nullb0\nwhile true; do echo 1 > submit_queues; echo 4 > submit_queues; done &\nwhile true; do echo 1 > power; echo 0 > power; done\n\nTest result:\n\nBUG: kernel NULL pointer dereference, address: 0000000000000148\nOops: 0000 [#1] PREEMPT SMP\nRIP: 0010:__lock_acquire+0x41d/0x28f0\nCall Trace:\n <TASK>\n lock_acquire+0x121/0x450\n down_write+0x5f/0x1d0\n simple_recursive_removal+0x12f/0x5c0\n blk_mq_debugfs_unregister_hctxs+0x7c/0x100\n blk_mq_update_nr_hw_queues+0x4a3/0x720\n nullb_update_nr_hw_queues+0x71/0xf0 [null_blk]\n nullb_device_submit_queues_store+0x79/0xf0 [null_blk]\n configfs_write_iter+0x119/0x1e0\n vfs_write+0x326/0x730\n ksys_write+0x74/0x150\n\nThis is because del_gendisk() can concurrent with\nblk_mq_update_nr_hw_queues():\n\nnullb_device_power_store\tnullb_apply_submit_queues\n null_del_dev\n del_gendisk\n\t\t\t\t nullb_update_nr_hw_queues\n\t\t\t\t  if (!dev->nullb)\n\t\t\t\t  // still set while gendisk is deleted\n\t\t\t\t   return 0\n\t\t\t\t  blk_mq_update_nr_hw_queues\n dev->nullb = NULL\n\nFix this problem by resuing the global mutex to protect\nnullb_device_power_store() and nullb_update_nr_hw_queues() from configfs."
            }
        ]
    },
    "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": "45919fbfe1c4",
                                            "version_value": "aaadb755f2d6"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.5",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "5.5",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.6.55",
                                                        "lessThanOrEqual": "6.6.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.9.4",
                                                        "lessThanOrEqual": "6.9.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.10",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/aaadb755f2d684f715a6eb85cb7243aa0c67dfa9",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/aaadb755f2d684f715a6eb85cb7243aa0c67dfa9"
            },
            {
                "url": "https://git.kernel.org/stable/c/5d0495473ee4c1d041b5a917f10446a22c047f47",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/5d0495473ee4c1d041b5a917f10446a22c047f47"
            },
            {
                "url": "https://git.kernel.org/stable/c/a2db328b0839312c169eb42746ec46fc1ab53ed2",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/a2db328b0839312c169eb42746ec46fc1ab53ed2"
            }
        ]
    },
    "generator": {
        "engine": "bippy-c9c4e1df01b2"
    }
}