netfilter: iptables: Fix null-ptr-deref in iptable_nat_table_init().

{
  "id": "27ed4125c09bca3ba675495d95340be4160b0c8d3f55a0047b4a4c323c3d3971",
  "url": "https://osv.dev/vulnerability/CVE-2024-42270",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "netfilter: iptables: Fix null-ptr-deref in iptable_nat_table_init().",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: netfilter: iptables: Fix null-ptr-deref in iptable_nat_table_init(). We had a report that iptables-restore sometimes triggered null-ptr-deref at boot time. [0] The problem is that iptable_nat_table_init() is exposed to user space before the kernel fully initialises netns. In the small race window, a user could call iptable_nat_table_init() that accesses net_generic(net, iptable_nat_net_id), which is available only after registering iptable_nat_net_ops. Let's call register_pernet_subsys() before xt_register_template(). [0]: bpfilter: Loaded bpfilter_umh pid 11702 Started bpfilter BUG: kernel NULL pointer dereference, address: 0000000000000013 PF: supervisor write access in kernel mode PF: error_code(0x0002) - not-present page PGD 0 P4D 0 PREEMPT SMP NOPTI CPU: 2 PID: 11879 Comm: iptables-restor Not tainted 6.1.92-99.174.amzn2023.x86_64 #1 Hardware name: Amazon EC2 c6i.4xlarge/, BIOS 1.0 10/16/2017 RIP: 0010:iptable_nat_table_init (net/ipv4/netfilter/iptable_nat.c:87 net/ipv4/netfilter/iptable_nat.c:121) iptable_nat Code: 10 4c 89 f6 48 89 ef e8 0b 19 bb ff 41 89 c4 85 c0 75 38 41 83 c7 01 49 83 c6 28 41 83 ff 04 75 dc 48 8b 44 24 08 48 8b 0c 24 <48> 89 08 4c 89 ef e8 a2 3b a2 cf 48 83 c4 10 44 89 e0 5b 5d 41 5c RSP: 0018:ffffbef902843cd0 EFLAGS: 00010246 RAX: 0000000000000013 RBX: ffff9f4b052caa20 RCX: ffff9f4b20988d80 RDX: 0000000000000000 RSI: 0000000000000064 RDI: ffffffffc04201c0 RBP: ffff9f4b29394000 R08:",
    "evidence": "osv:CVE-2024-42270",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.165",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.104",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.45",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.10.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2024-42270",
      "aliases": [
        "CVE-2024-42270"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "fdacd57c79b79a03c7ca88f706ad9fb7b46831c1"
                },
                {
                  "fixed": "b98ddb65fa1674b0e6b52de8af9103b63f51b643"
                },
                {
                  "fixed": "95590a4929027769af35b153645c0ab6fd22b29b"
                },
                {
                  "fixed": "70014b73d7539fcbb6b4ff5f37368d7241d8e626"
                },
                {
                  "fixed": "08ed888b69a22647153fe2bec55b7cd0a46102cc"
                },
                {
                  "fixed": "5830aa863981d43560748aa93589c0695191d95d"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-42270.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.15.0"
                },
                {
                  "fixed": "5.15.165"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.1.104"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.6.45"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.10.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-42270.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:34.241964365Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/08ed888b69a22647153fe2bec55b7cd0a46102cc",
        "https://git.kernel.org/stable/c/5830aa863981d43560748aa93589c0695191d95d",
        "https://git.kernel.org/stable/c/70014b73d7539fcbb6b4ff5f37368d7241d8e626",
        "https://git.kernel.org/stable/c/95590a4929027769af35b153645c0ab6fd22b29b",
        "https://git.kernel.org/stable/c/b98ddb65fa1674b0e6b52de8af9103b63f51b643",
        "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/42xxx/CVE-2024-42270.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2024-42270",
        "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/2024/42xxx/CVE-2024-42270.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2024-42270",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 501244,
  "published_at": "2024-08-17T08:54:25.178+00:00"
}