CVE-2025-40083 (GCVE-0-2025-40083)
Vulnerability from cvelistv5
Published
2025-10-29 13:37
Modified
2025-11-02 13:30
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_qfq: Fix null-deref in agg_dequeue To prevent a potential crash in agg_dequeue (net/sched/sch_qfq.c) when cl->qdisc->ops->peek(cl->qdisc) returns NULL, we check the return value before using it, similar to the existing approach in sch_hfsc.c. To avoid code duplication, the following changes are made: 1. Changed qdisc_warn_nonwc(include/net/pkt_sched.h) into a static inline function. 2. Moved qdisc_peek_len from net/sched/sch_hfsc.c to include/net/pkt_sched.h so that sch_qfq can reuse it. 3. Applied qdisc_peek_len in agg_dequeue to avoid crashing.
References
Impacted products
Vendor Product Version
Linux Linux Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
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{
  "containers": {
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      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/net/pkt_sched.h",
            "net/sched/sch_api.c",
            "net/sched/sch_hfsc.c",
            "net/sched/sch_qfq.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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          "programFiles": [
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            "net/sched/sch_hfsc.c",
            "net/sched/sch_qfq.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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              "version": "6.6.116",
              "versionType": "semver"
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              "version": "6.12.57",
              "versionType": "semver"
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              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.16",
              "versionType": "original_commit_for_fix"
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      ],
      "cpeApplicability": [
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              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_qfq: Fix null-deref in agg_dequeue\n\nTo prevent a potential crash in agg_dequeue (net/sched/sch_qfq.c)\nwhen cl-\u003eqdisc-\u003eops-\u003epeek(cl-\u003eqdisc) returns NULL, we check the return\nvalue before using it, similar to the existing approach in sch_hfsc.c.\n\nTo avoid code duplication, the following changes are made:\n\n1. Changed qdisc_warn_nonwc(include/net/pkt_sched.h) into a static\ninline function.\n\n2. Moved qdisc_peek_len from net/sched/sch_hfsc.c to\ninclude/net/pkt_sched.h so that sch_qfq can reuse it.\n\n3. Applied qdisc_peek_len in agg_dequeue to avoid crashing."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-11-02T13:30:42.936Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/6ffa9d66187188e3068b5a3895e6ae1ee34f9199"
        },
        {
          "url": "https://git.kernel.org/stable/c/6ff8e74c8f8a68ec07ef837b95425dfe900d060f"
        },
        {
          "url": "https://git.kernel.org/stable/c/dd831ac8221e691e9e918585b1003c7071df0379"
        }
      ],
      "title": "net/sched: sch_qfq: Fix null-deref in agg_dequeue",
      "x_generator": {
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  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-40083",
    "datePublished": "2025-10-29T13:37:01.868Z",
    "dateReserved": "2025-04-16T07:20:57.161Z",
    "dateUpdated": "2025-11-02T13:30:42.936Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-40083\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-10-29T14:15:54.900\",\"lastModified\":\"2025-11-02T14:15:35.870\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet/sched: sch_qfq: Fix null-deref in agg_dequeue\\n\\nTo prevent a potential crash in agg_dequeue (net/sched/sch_qfq.c)\\nwhen cl-\u003eqdisc-\u003eops-\u003epeek(cl-\u003eqdisc) returns NULL, we check the return\\nvalue before using it, similar to the existing approach in sch_hfsc.c.\\n\\nTo avoid code duplication, the following changes are made:\\n\\n1. Changed qdisc_warn_nonwc(include/net/pkt_sched.h) into a static\\ninline function.\\n\\n2. Moved qdisc_peek_len from net/sched/sch_hfsc.c to\\ninclude/net/pkt_sched.h so that sch_qfq can reuse it.\\n\\n3. Applied qdisc_peek_len in agg_dequeue to avoid crashing.\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/6ff8e74c8f8a68ec07ef837b95425dfe900d060f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/6ffa9d66187188e3068b5a3895e6ae1ee34f9199\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/dd831ac8221e691e9e918585b1003c7071df0379\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}


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