{
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    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2021-47506",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix use-after-free due to delegation race\n\nA delegation break could arrive as soon as we've called vfs_setlease.  A\ndelegation break runs a callback which immediately (in\nnfsd4_cb_recall_prepare) adds the delegation to del_recall_lru.  If we\nthen exit nfs4_set_delegation without hashing the delegation, it will be\nfreed as soon as the callback is done with it, without ever being\nremoved from del_recall_lru.\n\nSymptoms show up later as use-after-free or list corruption warnings,\nusually in the laundromat thread.\n\nI suspect aba2072f4523 \"nfsd: grant read delegations to clients holding\nwrites\" made this bug easier to hit, but I looked as far back as v3.0\nand it looks to me it already had the same problem.  So I'm not sure\nwhere the bug was introduced; it may have been there from the beginning."
            }
        ]
    },
    "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": "1da177e4c3f4",
                                            "version_value": "04a8d07f3d58"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "4.4.296",
                                                        "lessThanOrEqual": "4.4.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "4.9.294",
                                                        "lessThanOrEqual": "4.9.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "4.14.259",
                                                        "lessThanOrEqual": "4.14.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "4.19.222",
                                                        "lessThanOrEqual": "4.19.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.4.168",
                                                        "lessThanOrEqual": "5.4.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.10.85",
                                                        "lessThanOrEqual": "5.10.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.15.8",
                                                        "lessThanOrEqual": "5.15.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.16",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
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        "reference_data": [
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                "url": "https://git.kernel.org/stable/c/04a8d07f3d58308b92630045560799a3faa3ebce",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/04a8d07f3d58308b92630045560799a3faa3ebce"
            },
            {
                "url": "https://git.kernel.org/stable/c/348714018139c39533c55661a0c7c990671396b4",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/348714018139c39533c55661a0c7c990671396b4"
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            {
                "url": "https://git.kernel.org/stable/c/33645d3e22720cac1e4548f8fef57bf0649536ee",
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                "name": "https://git.kernel.org/stable/c/33645d3e22720cac1e4548f8fef57bf0649536ee"
            },
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                "url": "https://git.kernel.org/stable/c/2becaa990b93cbd2928292c0b669d3abb6cf06d4",
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                "name": "https://git.kernel.org/stable/c/2becaa990b93cbd2928292c0b669d3abb6cf06d4"
            },
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                "name": "https://git.kernel.org/stable/c/e0759696de6851d7536efddfdd2dfed4c4df1f09"
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                "name": "https://git.kernel.org/stable/c/eeb0711801f5e19ef654371b627682aed3b11373"
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            },
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                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/548ec0805c399c65ed66c6641be467f717833ab5"
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