block, bfq: Fix division by zero error on zero wsum

{
  "id": "13270d32819db9878a9da4be96148d4d33155253d2517979d60c8359ec55be8d",
  "url": "https://osv.dev/vulnerability/CVE-2023-54242",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "block, bfq: Fix division by zero error on zero wsum",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: block, bfq: Fix division by zero error on zero wsum When the weighted sum is zero the calculation of limit causes a division by zero error. Fix this by continuing to the next level. This was discovered by running as root: stress-ng --ioprio 0 Fixes divison by error oops: [ 521.450556] divide error: 0000 [#1] SMP NOPTI [ 521.450766] CPU: 2 PID: 2684464 Comm: stress-ng-iopri Not tainted 6.2.1-1280.native #1 [ 521.451117] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.1-0-g3208b098f51a-prebuilt.qemu.org 04/01/2014 [ 521.451627] RIP: 0010:bfqq_request_over_limit+0x207/0x400 [ 521.451875] Code: 01 48 8d 0c c8 74 0b 48 8b 82 98 00 00 00 48 8d 0c c8 8b 85 34 ff ff ff 48 89 ca 41 0f af 41 50 48 d1 ea 48 98 48 01 d0 31 d2 <48> f7 f1 41 39 41 48 89 85 34 ff ff ff 0f 8c 7b 01 00 00 49 8b 44 [ 521.452699] RSP: 0018:ffffb1af84eb3948 EFLAGS: 00010046 [ 521.452938] RAX: 000000000000003c RBX: 0000000000000000 RCX: 0000000000000000 [ 521.453262] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb1af84eb3978 [ 521.453584] RBP: ffffb1af84eb3a30 R08: 0000000000000001 R09: ffff8f88ab8a4ba0 [ 521.453905] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8f88ab8a4b18 [ 521.454224] R13: ffff8f8699093000 R14: 0000000000000001 R15: ffffb1af84eb3970 [ 521.454549] FS: 00005640b6b0b580(0000) GS:ffff8f88b3880000(0000) knlGS:0000000000000000 [ 521.454912] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 521.45",
    "evidence": "osv:CVE-2023-54242",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.1.30",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.3.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2023-54242",
      "aliases": [
        "CVE-2023-54242"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "76f1df88bbc2f984eb0418cc90de0a8384e63604"
                },
                {
                  "fixed": "1655cfc85250a224b0d9486c8136baeea33b9b5c"
                },
                {
                  "fixed": "c0346a59d719461248c6dc6f21c9e55ef836b66f"
                },
                {
                  "fixed": "e53413f8deedf738a6782cc14cc00bd5852ccf18"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-54242.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.17.0"
                },
                {
                  "fixed": "6.1.30"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.3.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-54242.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:52.946376529Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1655cfc85250a224b0d9486c8136baeea33b9b5c",
        "https://git.kernel.org/stable/c/c0346a59d719461248c6dc6f21c9e55ef836b66f",
        "https://git.kernel.org/stable/c/e53413f8deedf738a6782cc14cc00bd5852ccf18",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/54xxx/CVE-2023-54242.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-54242",
        "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/2023/54xxx/CVE-2023-54242.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-54242",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 521852,
  "published_at": "2025-12-30T12:11:30.503+00:00"
}