{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2021-47555",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-05-24T15:02:54.833Z",
        "datePublished": "2024-05-24T15:09:57.302Z",
        "dateUpdated": "2024-08-04T05:39:59.857Z"
    },
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                "shortName": "Linux",
                "dateUpdated": "2024-05-29T05:10:00.110Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: vlan: fix underflow for the real_dev refcnt\n\nInject error before dev_hold(real_dev) in register_vlan_dev(),\nand execute the following testcase:\n\nip link add dev dummy1 type dummy\nip link add name dummy1.100 link dummy1 type vlan id 100\nip link del dev dummy1\n\nWhen the dummy netdevice is removed, we will get a WARNING as following:\n\n=======================================================================\nrefcount_t: decrement hit 0; leaking memory.\nWARNING: CPU: 2 PID: 0 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0\n\nand an endless loop of:\n\n=======================================================================\nunregister_netdevice: waiting for dummy1 to become free. Usage count = -1073741824\n\nThat is because dev_put(real_dev) in vlan_dev_free() be called without\ndev_hold(real_dev) in register_vlan_dev(). It makes the refcnt of real_dev\nunderflow.\n\nMove the dev_hold(real_dev) to vlan_dev_init() which is the call-back of\nndo_init(). That makes dev_hold() and dev_put() for vlan's real_dev\nsymmetrical."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/8021q/vlan.c",
                        "net/8021q/vlan_dev.c"
                    ],
                    "versions": [
                        {
                            "version": "700602b662d7",
                            "lessThan": "5e44178864b3",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "e04a7a84bb77",
                            "lessThan": "6e800ee43218",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "21032425c36f",
                            "lessThan": "f7fc72a508cf",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "563bcbae3ba2",
                            "lessThan": "01d9cc2dea3f",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/8021q/vlan.c",
                        "net/8021q/vlan_dev.c"
                    ],
                    "versions": [
                        {
                            "version": "5.4.160",
                            "lessThan": "5.4.163",
                            "status": "affected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.10.80",
                            "lessThan": "5.10.83",
                            "status": "affected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.15.3",
                            "lessThan": "5.15.6",
                            "status": "affected",
                            "versionType": "custom"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/5e44178864b38dd70b877985abd7d86fdb95f27d"
                },
                {
                    "url": "https://git.kernel.org/stable/c/6e800ee43218a56acc93676bbb3d93b74779e555"
                },
                {
                    "url": "https://git.kernel.org/stable/c/f7fc72a508cf115c273a7a29350069def1041890"
                },
                {
                    "url": "https://git.kernel.org/stable/c/01d9cc2dea3fde3bad6d27f464eff463496e2b00"
                }
            ],
            "title": "net: vlan: fix underflow for the real_dev refcnt",
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                "engine": "bippy-a5840b7849dd"
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        },
        "adp": [
            {
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                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2021-47555",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "version": "2.0.3",
                                "timestamp": "2024-05-29T16:04:46.132423Z"
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                    "dateUpdated": "2024-06-04T17:14:50.900Z"
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                    "shortName": "CVE",
                    "dateUpdated": "2024-08-04T05:39:59.857Z"
                },
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://git.kernel.org/stable/c/5e44178864b38dd70b877985abd7d86fdb95f27d",
                        "tags": [
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