{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2021-47242",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-04-10T18:59:19.532Z",
        "datePublished": "2024-05-21T14:19:41.665Z",
        "dateUpdated": "2024-08-04T05:32:07.921Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2024-05-29T05:04:32.551Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix soft lookup in subflow_error_report()\n\nMaxim reported a soft lookup in subflow_error_report():\n\n watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:0]\n RIP: 0010:native_queued_spin_lock_slowpath\n RSP: 0018:ffffa859c0003bc0 EFLAGS: 00000202\n RAX: 0000000000000101 RBX: 0000000000000001 RCX: 0000000000000000\n RDX: ffff9195c2772d88 RSI: 0000000000000000 RDI: ffff9195c2772d88\n RBP: ffff9195c2772d00 R08: 00000000000067b0 R09: c6e31da9eb1e44f4\n R10: ffff9195ef379700 R11: ffff9195edb50710 R12: ffff9195c2772d88\n R13: ffff9195f500e3d0 R14: ffff9195ef379700 R15: ffff9195ef379700\n FS:  0000000000000000(0000) GS:ffff91961f400000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000000c000407000 CR3: 0000000002988000 CR4: 00000000000006f0\n Call Trace:\n  <IRQ>\n _raw_spin_lock_bh\n subflow_error_report\n mptcp_subflow_data_available\n __mptcp_move_skbs_from_subflow\n mptcp_data_ready\n tcp_data_queue\n tcp_rcv_established\n tcp_v4_do_rcv\n tcp_v4_rcv\n ip_protocol_deliver_rcu\n ip_local_deliver_finish\n __netif_receive_skb_one_core\n netif_receive_skb\n rtl8139_poll 8139too\n __napi_poll\n net_rx_action\n __do_softirq\n __irq_exit_rcu\n common_interrupt\n  </IRQ>\n\nThe calling function - mptcp_subflow_data_available() - can be invoked\nfrom different contexts:\n- plain ssk socket lock\n- ssk socket lock + mptcp_data_lock\n- ssk socket lock + mptcp_data_lock + msk socket lock.\n\nSince subflow_error_report() tries to acquire the mptcp_data_lock, the\nlatter two call chains will cause soft lookup.\n\nThis change addresses the issue moving the error reporting call to\nouter functions, where the held locks list is known and the we can\nacquire only the needed one."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/mptcp/protocol.c",
                        "net/mptcp/subflow.c"
                    ],
                    "versions": [
                        {
                            "version": "15cc10453398",
                            "lessThan": "27ef25c72373",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "15cc10453398",
                            "lessThan": "499ada507336",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/mptcp/protocol.c",
                        "net/mptcp/subflow.c"
                    ],
                    "versions": [
                        {
                            "version": "5.12",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.12",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.12.13",
                            "lessThanOrEqual": "5.12.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.13",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/27ef25c72373222aaa5fe7b5cd890ae9cfb89a8d"
                },
                {
                    "url": "https://git.kernel.org/stable/c/499ada5073361c631f2a3c4a8aed44d53b6f82ec"
                }
            ],
            "title": "mptcp: fix soft lookup in subflow_error_report()",
            "x_generator": {
                "engine": "bippy-a5840b7849dd"
            }
        },
        "adp": [
            {
                "problemTypes": [
                    {
                        "descriptions": [
                            {
                                "type": "CWE",
                                "cweId": "CWE-667",
                                "lang": "en",
                                "description": "CWE-667 Improper Locking"
                            }
                        ]
                    }
                ],
                "affected": [
                    {
                        "vendor": "linux",
                        "product": "linux_kernel",
                        "cpes": [
                            "cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*"
                        ],
                        "defaultStatus": "unknown",
                        "versions": [
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                                "version": "15cc10453398",
                                "status": "affected",
                                "lessThan": "27ef25c72373",
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                            }
                        ]
                    },
                    {
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                        "product": "linux_kernel",
                        "cpes": [
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                        ],
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                        "versions": [
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                        ],
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                        "defaultStatus": "unknown",
                        "versions": [
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                                "version": "0",
                                "status": "unaffected",
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                                "versionType": "custom"
                            }
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                    },
                    {
                        "vendor": "linux",
                        "product": "linux_kernel",
                        "cpes": [
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                        ],
                        "defaultStatus": "unknown",
                        "versions": [
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                                "version": "5.13",
                                "status": "unaffected"
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                                "status": "unaffected",
                                "lessThanOrEqual": "5.13",
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                            }
                        ]
                    }
                ],
                "metrics": [
                    {
                        "cvssV3_1": {
                            "scope": "UNCHANGED",
                            "version": "3.1",
                            "baseScore": 7.8,
                            "attackVector": "LOCAL",
                            "baseSeverity": "HIGH",
                            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                            "integrityImpact": "HIGH",
                            "userInteraction": "REQUIRED",
                            "attackComplexity": "LOW",
                            "availabilityImpact": "HIGH",
                            "privilegesRequired": "NONE",
                            "confidentialityImpact": "HIGH"
                        }
                    },
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2024-06-06T19:00:17.036073Z",
                                "id": "CVE-2021-47242",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2024-07-07T19:44:05.240Z"
                }
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                    "orgId": "af854a3a-2127-422b-91ae-364da2661108",
                    "shortName": "CVE",
                    "dateUpdated": "2024-08-04T05:32:07.921Z"
                },
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://git.kernel.org/stable/c/27ef25c72373222aaa5fe7b5cd890ae9cfb89a8d",
                        "tags": [
                            "x_transferred"
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                    {
                        "url": "https://git.kernel.org/stable/c/499ada5073361c631f2a3c4a8aed44d53b6f82ec",
                        "tags": [
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}