net: drop bad gso csum_start and offset in virtio_net_hdr

{
  "id": "cf26edd19dec9c9abbcd9e3200ff1f9b9743d2aa7d62c8daabd25943104b7520",
  "url": "https://osv.dev/vulnerability/CVE-2024-43897",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "net: drop bad gso csum_start and offset in virtio_net_hdr",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: net: drop bad gso csum_start and offset in virtio_net_hdr Tighten csum_start and csum_offset checks in virtio_net_hdr_to_skb for GSO packets. The function already checks that a checksum requested with VIRTIO_NET_HDR_F_NEEDS_CSUM is in skb linear. But for GSO packets this might not hold for segs after segmentation. Syzkaller demonstrated to reach this warning in skb_checksum_help offset = skb_checksum_start_offset(skb); ret = -EINVAL; if (WARN_ON_ONCE(offset >= skb_headlen(skb))) By injecting a TSO packet: WARNING: CPU: 1 PID: 3539 at net/core/dev.c:3284 skb_checksum_help+0x3d0/0x5b0 ip_do_fragment+0x209/0x1b20 net/ipv4/ip_output.c:774 ip_finish_output_gso net/ipv4/ip_output.c:279 [inline] __ip_finish_output+0x2bd/0x4b0 net/ipv4/ip_output.c:301 iptunnel_xmit+0x50c/0x930 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x2296/0x2c70 net/ipv4/ip_tunnel.c:813 __gre_xmit net/ipv4/ip_gre.c:469 [inline] ipgre_xmit+0x759/0xa60 net/ipv4/ip_gre.c:661 __netdev_start_xmit include/linux/netdevice.h:4850 [inline] netdev_start_xmit include/linux/netdevice.h:4864 [inline] xmit_one net/core/dev.c:3595 [inline] dev_hard_start_xmit+0x261/0x8c0 net/core/dev.c:3611 __dev_queue_xmit+0x1b97/0x3c90 net/core/dev.c:4261 packet_snd net/packet/af_packet.c:3073 [inline] The geometry of the bad input packet at tcp_gso_segment: [ 52.003050][ T8403] skb len=12202 headroom=244 headlen=12093 tailroom=0 [ 52.003050][ T8403] mac=(168,24) mac_len=24 ",
    "evidence": "osv:CVE-2024-43897",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.167",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.107",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.46",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.10.5",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2024-43897",
      "aliases": [
        "CVE-2024-43897"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "27874ca77bd2b05a3779c7b3a5c75d8dd7f0b40f"
                },
                {
                  "fixed": "413e785a89f8bde0d4156a54b8ac2fa003c06756"
                }
              ]
            },
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "5b1997487a3f3373b0f580c8a20b56c1b64b0775"
                },
                {
                  "fixed": "f01c5e335fbb7fb612d40f14a3c02e2612a43d3b"
                }
              ]
            },
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "90d41ebe0cd4635f6410471efc1dd71b33e894cf"
                },
                {
                  "fixed": "6772c4868a8e7ad5305957cdb834ce881793acb7"
                }
              ]
            },
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "e9164903b8b303c34723177b02fe91e49e3c4cd7"
                },
                {
                  "fixed": "2edbb3e8838c672cd7e247e47989df9d03fc6668"
                }
              ]
            },
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "e269d79c7d35aa3808b1f3c1737d63dab504ddc8"
                },
                {
                  "fixed": "89add40066f9ed9abe5f7f886fe5789ff7e0c50e"
                }
              ]
            }
          ],
          "versions": [
            "v5.15.166",
            "v5.15.165",
            "v6.1.106",
            "v6.1.105",
            "v6.1.104",
            "v6.1.103",
            "v6.6.45",
            "v6.6.44",
            "v6.10.4",
            "v6.10.3"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-43897.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.15.165"
                },
                {
                  "fixed": "5.15.167"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.1.103"
                },
                {
                  "fixed": "6.1.107"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.6.44"
                },
                {
                  "fixed": "6.6.46"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.10.3"
                },
                {
                  "fixed": "6.10.5"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-43897.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:24.714739495Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2edbb3e8838c672cd7e247e47989df9d03fc6668",
        "https://git.kernel.org/stable/c/413e785a89f8bde0d4156a54b8ac2fa003c06756",
        "https://git.kernel.org/stable/c/6772c4868a8e7ad5305957cdb834ce881793acb7",
        "https://git.kernel.org/stable/c/89add40066f9ed9abe5f7f886fe5789ff7e0c50e",
        "https://git.kernel.org/stable/c/f01c5e335fbb7fb612d40f14a3c02e2612a43d3b",
        "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/43xxx/CVE-2024-43897.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2024-43897",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/43xxx/CVE-2024-43897.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2024-43897",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 490835,
  "published_at": "2024-08-26T10:10:53.972+00:00"
}