cvelist/2021/46xxx/CVE-2021-46942.json

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    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2021-46942",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: fix shared sqpoll cancellation hangs\n\n[  736.982891] INFO: task iou-sqp-4294:4295 blocked for more than 122 seconds.\n[  736.982897] Call Trace:\n[  736.982901]  schedule+0x68/0xe0\n[  736.982903]  io_uring_cancel_sqpoll+0xdb/0x110\n[  736.982908]  io_sqpoll_cancel_cb+0x24/0x30\n[  736.982911]  io_run_task_work_head+0x28/0x50\n[  736.982913]  io_sq_thread+0x4e3/0x720\n\nWe call io_uring_cancel_sqpoll() one by one for each ctx either in\nsq_thread() itself or via task works, and it's intended to cancel all\nrequests of a specified context. However the function uses per-task\ncounters to track the number of inflight requests, so it counts more\nrequests than available via currect io_uring ctx and goes to sleep for\nthem to appear (e.g. from IRQ), that will never happen.\n\nCancel a bit more than before, i.e. all ctxs that share sqpoll\nand continue to use shared counters. Don't forget that we should not\nremove ctx from the list before running that task_work sqpoll-cancel,\notherwise the function wouldn't be able to find the context and will\nhang."
            }
        ]
    },
    "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": "37d1e2e3642e",
                                            "version_value": "cb5e0b3d0f99"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.12",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "5.12",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "5.12.3",
                                                        "lessThanOrEqual": "5.12.*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "5.13",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
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    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/cb5e0b3d0f993a6268c1a2c7ede2f9aa0c17ef68",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/cb5e0b3d0f993a6268c1a2c7ede2f9aa0c17ef68"
            },
            {
                "url": "https://git.kernel.org/stable/c/734551df6f9bedfbefcd113ede665945e9de0b99",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/734551df6f9bedfbefcd113ede665945e9de0b99"
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