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CVE-2026-98010

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net/sched: drr: clamp quantum in change class drr_change_class() rejects explicit quantum==0 but falls back to psched_mtu() with no floor. With a crafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1 (or a zero psched_mtu on a headerless device) makes the deficit-refill loop spin under the qdisc lock. Add clamp_t(u32, quantum, 256, 1<<20) after the zero reject and on the fallback path. The explicit-zero reject is preserved. Conditions to recreate the bug: CONFIG_NET_SCH_DRR=y. Requires CAP_NET_ADMIN (namespace-local via unshare -Urn suffices). tc qdisc add dev dummy0 root drr tc class add dev dummy0 parent 1: classid 1:1 drr quantum 1

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-25 11:17:29.320000
Last modified
2026-10-19 10:17:52.400000
View original CVE JSON
{
  "id": "CVE-2026-98010",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-25T11:17:29.320",
  "lastModified": "2026-10-19T10:17:52.400",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: drr: clamp quantum in change class\n\ndrr_change_class() rejects explicit quantum==0 but falls back to\npsched_mtu() with no floor. With a crafted size table qdisc_pkt_len\nreaches ~2 GiB, so quantum=1 (or a zero psched_mtu on a headerless\ndevice) makes the deficit-refill loop spin under the qdisc lock.\n\nAdd clamp_t(u32, quantum, 256, 1<<20) after the zero reject and on the\nfallback path. The explicit-zero reject is preserved.\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_DRR=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root drr\n  tc class add dev dummy0 parent 1: classid 1:1 drr quantum 1"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/sched/sch_drr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "13d2a1d2b032de08d7dcab6a1edcd47802681f96",
              "lessThan": "e2297bbf9cf6ece86f1d1f8c683517a994990f9e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13d2a1d2b032de08d7dcab6a1edcd47802681f96",
              "lessThan": "560794ee6e040b6e1c4ac2b3c8909f341a4596ee",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13d2a1d2b032de08d7dcab6a1edcd47802681f96",
              "lessThan": "23fea7e6736b2e1c6f6f2f05cccf33d36834da73",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13d2a1d2b032de08d7dcab6a1edcd47802681f96",
              "lessThan": "b464affe9f9dfe41ac48930c376e3fb8596651b0",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13d2a1d2b032de08d7dcab6a1edcd47802681f96",
              "lessThan": "dc8b374214ef5bba4882bbd95b361e42555cfc0d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13d2a1d2b032de08d7dcab6a1edcd47802681f96",
              "lessThan": "d43cded350fe1218493ad3d37a276aff14108ae6",
              "versionType": "git",
              "status": "affected"
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            {
              "version": "13d2a1d2b032de08d7dcab6a1edcd47802681f96",
              "lessThan": "8f756ae1c87414ce9cc21b30e6e4c036d6e9e80b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13d2a1d2b032de08d7dcab6a1edcd47802681f96",
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              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/sched/sch_drr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2.6.29",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "2.6.29",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.271",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.222",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.189",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.158",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.111",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.53",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.7",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/23fea7e6736b2e1c6f6f2f05cccf33d36834da73",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/560794ee6e040b6e1c4ac2b3c8909f341a4596ee",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8382abec0f1568d0a5590d75a3df92f23fcf5196",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
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      "url": "https://git.kernel.org/stable/c/8f756ae1c87414ce9cc21b30e6e4c036d6e9e80b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b464affe9f9dfe41ac48930c376e3fb8596651b0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d43cded350fe1218493ad3d37a276aff14108ae6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/dc8b374214ef5bba4882bbd95b361e42555cfc0d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e2297bbf9cf6ece86f1d1f8c683517a994990f9e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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  ]
}