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    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2021-47556",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-05-24T15:02:54.833Z",
        "datePublished": "2024-05-24T15:09:57.983Z",
        "dateUpdated": "2026-05-11T13:56:54.697Z"
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                    "lang": "en",
                    "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."
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                    "vendor": "Linux",
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                    "url": "https://git.kernel.org/stable/c/0276af2176c78771da7f311621a25d7608045827"
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