{
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    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2021-47556",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nethtool: ioctl: fix potential NULL deref in ethtool_set_coalesce()\n\nethtool_set_coalesce() now uses both the .get_coalesce() and\n.set_coalesce() callbacks. But the check for their availability is\nbuggy, so changing the coalesce settings on a device where the driver\nprovides only _one_ of the callbacks results in a NULL pointer\ndereference instead of an -EOPNOTSUPP.\n\nFix the condition so that the availability of both callbacks is\nensured. This also matches the netlink code.\n\nNote that reproducing this requires some effort - it only affects the\nlegacy ioctl path, and needs a specific combination of driver options:\n- have .get_coalesce() and .coalesce_supported but no\n .set_coalesce(), or\n- have .set_coalesce() but no .get_coalesce(). Here eg. ethtool doesn't\n  cause the crash as it first attempts to call ethtool_get_coalesce()\n  and bails out on error."
            }
        ]
    },
    "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": "f3ccfda19319",
                                            "version_value": "abfdd9e2f0f9"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.15",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "5.15",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.15.6",
                                                        "lessThanOrEqual": "5.15.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.16",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
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    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/abfdd9e2f0f9699015d72317f74154d3e53664e6",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/abfdd9e2f0f9699015d72317f74154d3e53664e6"
            },
            {
                "url": "https://git.kernel.org/stable/c/0276af2176c78771da7f311621a25d7608045827",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/0276af2176c78771da7f311621a25d7608045827"
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