{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2023-53531",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2023-53531",
    "idYear": 2023,
    "status": "PUBLISHED",
    "publishedAt": "2025-10-01T11:46:15.949Z",
    "updatedAt": "2026-08-05T09:14:38.269Z",
    "importedAt": "2026-10-24T01:57:03.413Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "null_blk: fix poll request timeout handling",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnull_blk: fix poll request timeout handling\n\nWhen doing io_uring benchmark on /dev/nullb0, it's easy to crash the\nkernel if poll requests timeout triggered, as reported by David. [1]\n\nBUG: kernel NULL pointer dereference, address: 0000000000000008\nWorkqueue: kblockd blk_mq_timeout_work\nRIP: 0010:null_timeout_rq+0x4e/0x91\nCall Trace:\n ? null_timeout_rq+0x4e/0x91\n blk_mq_handle_expired+0x31/0x4b\n bt_iter+0x68/0x84\n ? bt_tags_iter+0x81/0x81\n __sbitmap_for_each_set.constprop.0+0xb0/0xf2\n ? __blk_mq_complete_request_remote+0xf/0xf\n bt_for_each+0x46/0x64\n ? __blk_mq_complete_request_remote+0xf/0xf\n ? percpu_ref_get_many+0xc/0x2a\n blk_mq_queue_tag_busy_iter+0x14d/0x18e\n blk_mq_timeout_work+0x95/0x127\n process_one_work+0x185/0x263\n worker_thread+0x1b5/0x227\n\nThis is indeed a race problem between null_timeout_rq() and null_poll().\n\nnull_poll()\t\t\t\tnull_timeout_rq()\n  spin_lock(&nq->poll_lock)\n  list_splice_init(&nq->poll_list, &list)\n  spin_unlock(&nq->poll_lock)\n\n  while (!list_empty(&list))\n    req = list_first_entry()\n    list_del_init()\n    ...\n    blk_mq_add_to_batch()\n    // req->rq_next = NULL\n\t\t\t\t\tspin_lock(&nq->poll_lock)\n\n\t\t\t\t\t// rq->queuelist->next == NULL\n\t\t\t\t\tlist_del_init(&rq->queuelist)\n\n\t\t\t\t\tspin_unlock(&nq->poll_lock)\n\nFix these problems by setting requests state to MQ_RQ_COMPLETE under\nnq->poll_lock protection, in which null_timeout_rq() can safely detect\nthis race and early return.\n\nNote this patch just fix the kernel panic when request timeout happen.\n\n[1] https://lore.kernel.org/all/3893581.1691785261@warthog.procyon.org.uk/",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0a593fbbc245a85940ed34caa3aa1e4cb060c54b",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a0b4a0666beacfe8add9c71d8922475541dbae73"
            },
            {
              "version": "0a593fbbc245a85940ed34caa3aa1e4cb060c54b",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a7cb2e709f2927cc3c76781df3e45de2381b3b9d"
            },
            {
              "version": "0a593fbbc245a85940ed34caa3aa1e4cb060c54b",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5a26e45edb4690d58406178b5a9ea4c6dcf2c105"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.16",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.16"
            },
            {
              "version": "6.1.54",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.5.4",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.5.*"
            },
            {
              "version": "6.6",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}