{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-80925",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-26T14:34:25.802Z",
        "datePublished": "2026-09-09T16:19:44.748Z",
        "dateUpdated": "2026-10-19T08:45:09.219Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-19T08:45:09.219Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvlan: fix skb_under_panic and races when toggling HW VLAN offload\n\nToggling hardware VLAN TX offload (NETIF_F_HW_VLAN_CTAG_TX or\nNETIF_F_HW_VLAN_STAG_TX) on a lower device invokes vlan_transfer_features(),\nwhich dynamically changed vlandev->hard_header_len.\n\nThis causes two issues:\n1. Lockless TX paths (e.g. packet_snd in af_packet.c, ip6_finish_output2)\n   read dev->hard_header_len without holding RTNL lock. Mutating\n   hard_header_len dynamically under RTNL creates a data race where upper\n   layers reserve insufficient headroom based on a stale hard_header_len,\n   resulting in skb_under_panic when vlan_dev_hard_header() is called.\n2. In addition, vlan_transfer_features() updated hard_header_len without\n   updating header_ops, causing a mismatch between allocated headroom\n   and header creation.\n\nAlways setting dev->hard_header_len = real_dev->hard_header_len and\ndev->needed_headroom = real_dev->needed_headroom + VLAN_HLEN unconditionally\nensures:\n- dev->hard_header_len remains 100% static and immutable at real_dev->hard_header_len,\n  eliminating all dynamic runtime updates and data races on hard_header_len.\n- Upper layers allocating skbs via LL_RESERVED_SPACE() will always reserve\n  sufficient headroom for software VLAN tag insertion (real_dev->hard_header_len +\n  real_dev->needed_headroom + VLAN_HLEN).\n- vlandev inherits real_dev->needed_tailroom so underlying trailer/padding/ICV\n  requirements are honored.\n- AF_PACKET SOCK_RAW network header offsets remain correctly aligned at\n  real_dev->hard_header_len.\n- vlan_header_ops is used unconditionally.\n\nNote to stable teams: Make sure to backport these commits:\n\ne16e960d55a4 (\"ipvlan: inherit needed_headroom and needed_tailroom from phy_dev\")\ncef51860becd (\"macvlan: inherit needed_headroom and needed_tailroom from lowerdev\")"
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/8021q/vlan_dev.c"
                    ],
                    "versions": [
                        {
                            "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                            "lessThan": "b38d7a4bc9c17e1d437696da25f9fbc286614d9d",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                            "lessThan": "b30fe4de285b9bdaf9508740191f69f7cd83b8fa",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                            "lessThan": "1517d1996b5236fe69eccd9d253f725e06996eb1",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                            "lessThan": "a29f3b884ba50217e6f50414f568073221e2bb07",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                            "lessThan": "447cbe95ebb95392b5d8f6a01c0556826919ce23",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/8021q/vlan_dev.c"
                    ],
                    "versions": [
                        {
                            "version": "2.6.12",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "2.6.12",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.158",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.111",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.51",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.3",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.12",
                                    "versionEndExcluding": "6.6.158"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.12",
                                    "versionEndExcluding": "6.12.111"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.12",
                                    "versionEndExcluding": "6.18.51"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.12",
                                    "versionEndExcluding": "7.2.3"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.12",
                                    "versionEndExcluding": "7.3"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/b38d7a4bc9c17e1d437696da25f9fbc286614d9d"
                },
                {
                    "url": "https://git.kernel.org/stable/c/b30fe4de285b9bdaf9508740191f69f7cd83b8fa"
                },
                {
                    "url": "https://git.kernel.org/stable/c/1517d1996b5236fe69eccd9d253f725e06996eb1"
                },
                {
                    "url": "https://git.kernel.org/stable/c/a29f3b884ba50217e6f50414f568073221e2bb07"
                },
                {
                    "url": "https://git.kernel.org/stable/c/447cbe95ebb95392b5d8f6a01c0556826919ce23"
                }
            ],
            "title": "vlan: fix skb_under_panic and races when toggling HW VLAN offload",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}