{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/net/inet_frag.h",
            "include/net/ipv6_frag.h",
            "net/ipv4/inet_fragment.c",
            "net/ipv4/ip_fragment.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "c70df25214ac9b32b53e18e6ae3b8f073ffa6903",
              "status": "affected",
              "version": "d5dd88794a13c2f24cce31abad7a0a6c5e0ed2db",
              "versionType": "git"
            },
            {
              "lessThan": "006a5035b495dec008805df249f92c22c89c3d2e",
              "status": "affected",
              "version": "d5dd88794a13c2f24cce31abad7a0a6c5e0ed2db",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/net/inet_frag.h",
            "include/net/ipv6_frag.h",
            "net/ipv4/inet_fragment.c",
            "net/ipv4/ip_fragment.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.3"
            },
            {
              "lessThan": "5.3",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.19-rc2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.3",
                  "versionStartIncluding": "5.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19-rc2",
                  "versionStartIncluding": "5.3",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ninet: frags: flush pending skbs in fqdir_pre_exit()\n\nWe have been seeing occasional deadlocks on pernet_ops_rwsem since\nSeptember in NIPA. The stuck task was usually modprobe (often loading\na driver like ipvlan), trying to take the lock as a Writer.\nlockdep does not track readers for rwsems so the read wasn\u0027t obvious\nfrom the reports.\n\nOn closer inspection the Reader holding the lock was conntrack looping\nforever in nf_conntrack_cleanup_net_list(). Based on past experience\nwith occasional NIPA crashes I looked thru the tests which run before\nthe crash and noticed that the crash follows ip_defrag.sh. An immediate\nred flag. Scouring thru (de)fragmentation queues reveals skbs sitting\naround, holding conntrack references.\n\nThe problem is that since conntrack depends on nf_defrag_ipv6,\nnf_defrag_ipv6 will load first. Since nf_defrag_ipv6 loads first its\nnetns exit hooks run _after_ conntrack\u0027s netns exit hook.\n\nFlush all fragment queue SKBs during fqdir_pre_exit() to release\nconntrack references before conntrack cleanup runs. Also flush\nthe queues in timer expiry handlers when they discover fqdir-\u003edead\nis set, in case packet sneaks in while we\u0027re running the pre_exit\nflush.\n\nThe commit under Fixes is not exactly the culprit, but I think\npreviously the timer firing would eventually unblock the spinning\nconntrack."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-01-13T15:28:47.106Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/c70df25214ac9b32b53e18e6ae3b8f073ffa6903"
        },
        {
          "url": "https://git.kernel.org/stable/c/006a5035b495dec008805df249f92c22c89c3d2e"
        }
      ],
      "title": "inet: frags: flush pending skbs in fqdir_pre_exit()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-68768",
    "datePublished": "2026-01-13T15:28:47.106Z",
    "dateReserved": "2025-12-24T10:30:51.034Z",
    "dateUpdated": "2026-01-13T15:28:47.106Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-68768\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-01-13T16:15:56.247\",\"lastModified\":\"2026-01-14T16:26:00.933\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\ninet: frags: flush pending skbs in fqdir_pre_exit()\\n\\nWe have been seeing occasional deadlocks on pernet_ops_rwsem since\\nSeptember in NIPA. The stuck task was usually modprobe (often loading\\na driver like ipvlan), trying to take the lock as a Writer.\\nlockdep does not track readers for rwsems so the read wasn\u0027t obvious\\nfrom the reports.\\n\\nOn closer inspection the Reader holding the lock was conntrack looping\\nforever in nf_conntrack_cleanup_net_list(). Based on past experience\\nwith occasional NIPA crashes I looked thru the tests which run before\\nthe crash and noticed that the crash follows ip_defrag.sh. An immediate\\nred flag. Scouring thru (de)fragmentation queues reveals skbs sitting\\naround, holding conntrack references.\\n\\nThe problem is that since conntrack depends on nf_defrag_ipv6,\\nnf_defrag_ipv6 will load first. Since nf_defrag_ipv6 loads first its\\nnetns exit hooks run _after_ conntrack\u0027s netns exit hook.\\n\\nFlush all fragment queue SKBs during fqdir_pre_exit() to release\\nconntrack references before conntrack cleanup runs. Also flush\\nthe queues in timer expiry handlers when they discover fqdir-\u003edead\\nis set, in case packet sneaks in while we\u0027re running the pre_exit\\nflush.\\n\\nThe commit under Fixes is not exactly the culprit, but I think\\npreviously the timer firing would eventually unblock the spinning\\nconntrack.\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/006a5035b495dec008805df249f92c22c89c3d2e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c70df25214ac9b32b53e18e6ae3b8f073ffa6903\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}