cvelist/2021/47xxx/CVE-2021-47107.json

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        "ID": "CVE-2021-47107",
        "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 READDIR buffer overflow\n\nIf a client sends a READDIR count argument that is too small (say,\nzero), then the buffer size calculation in the new init_dirlist\nhelper functions results in an underflow, allowing the XDR stream\nfunctions to write beyond the actual buffer.\n\nThis calculation has always been suspect. NFSD has never sanity-\nchecked the READDIR count argument, but the old entry encoders\nmanaged the problem correctly.\n\nWith the commits below, entry encoding changed, exposing the\nunderflow to the pointer arithmetic in xdr_reserve_space().\n\nModern NFS clients attempt to retrieve as much data as possible\nfor each READDIR request. Also, we have no unit tests that\nexercise the behavior of READDIR at the lower bound of @count\nvalues. Thus this case was missed during testing."
            }
        ]
    },
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                    {
                        "lang": "eng",
                        "value": "n/a"
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        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
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                                            "version_affected": "<",
                                            "version_name": "37aa5e640222",
                                            "version_value": "9e291a6a28d3"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "7f87fc2d34d4",
                                            "version_value": "eabc0aab98e5"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.13",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "5.13",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "5.15.12",
                                                        "lessThanOrEqual": "5.15.*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "5.16",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
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                                                "defaultStatus": "affected"
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                        ]
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    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/9e291a6a28d32545ed2fd959a8165144d1724df1",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/9e291a6a28d32545ed2fd959a8165144d1724df1"
            },
            {
                "url": "https://git.kernel.org/stable/c/eabc0aab98e5218ceecd82069b0d6fdfff5ee885",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/eabc0aab98e5218ceecd82069b0d6fdfff5ee885"
            },
            {
                "url": "https://git.kernel.org/stable/c/53b1119a6e5028b125f431a0116ba73510d82a72",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/53b1119a6e5028b125f431a0116ba73510d82a72"
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