{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/block/ublk_drv.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0460e09a614291f06c008443f47393c37b7358e7",
              "status": "affected",
              "version": "71f28f3136aff5890cd56de78abc673f8393cad9",
              "versionType": "git"
            },
            {
              "lessThan": "c258f5c4502c9667bccf5d76fa731ab9c96687c1",
              "status": "affected",
              "version": "71f28f3136aff5890cd56de78abc673f8393cad9",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/block/ublk_drv.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.0"
            },
            {
              "lessThan": "6.0",
              "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": "6.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19-rc2",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nublk: fix deadlock when reading partition table\n\nWhen one process(such as udev) opens ublk block device (e.g., to read\nthe partition table via bdev_open()), a deadlock[1] can occur:\n\n1. bdev_open() grabs disk-\u003eopen_mutex\n2. The process issues read I/O to ublk backend to read partition table\n3. In __ublk_complete_rq(), blk_update_request() or blk_mq_end_request()\n   runs bio-\u003ebi_end_io() callbacks\n4. If this triggers fput() on file descriptor of ublk block device, the\n   work may be deferred to current task\u0027s task work (see fput() implementation)\n5. This eventually calls blkdev_release() from the same context\n6. blkdev_release() tries to grab disk-\u003eopen_mutex again\n7. Deadlock: same task waiting for a mutex it already holds\n\nThe fix is to run blk_update_request() and blk_mq_end_request() with bottom\nhalves disabled. This forces blkdev_release() to run in kernel work-queue\ncontext instead of current task work context, and allows ublk server to make\nforward progress, and avoids the deadlock.\n\n[axboe: rewrite comment in ublk]"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-01-13T15:29:25.392Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/0460e09a614291f06c008443f47393c37b7358e7"
        },
        {
          "url": "https://git.kernel.org/stable/c/c258f5c4502c9667bccf5d76fa731ab9c96687c1"
        }
      ],
      "title": "ublk: fix deadlock when reading partition table",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-68823",
    "datePublished": "2026-01-13T15:29:25.392Z",
    "dateReserved": "2025-12-24T10:30:51.048Z",
    "dateUpdated": "2026-01-13T15:29:25.392Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-68823\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-01-13T16:16:04.660\",\"lastModified\":\"2026-01-13T16:16:04.660\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nublk: fix deadlock when reading partition table\\n\\nWhen one process(such as udev) opens ublk block device (e.g., to read\\nthe partition table via bdev_open()), a deadlock[1] can occur:\\n\\n1. bdev_open() grabs disk-\u003eopen_mutex\\n2. The process issues read I/O to ublk backend to read partition table\\n3. In __ublk_complete_rq(), blk_update_request() or blk_mq_end_request()\\n   runs bio-\u003ebi_end_io() callbacks\\n4. If this triggers fput() on file descriptor of ublk block device, the\\n   work may be deferred to current task\u0027s task work (see fput() implementation)\\n5. This eventually calls blkdev_release() from the same context\\n6. blkdev_release() tries to grab disk-\u003eopen_mutex again\\n7. Deadlock: same task waiting for a mutex it already holds\\n\\nThe fix is to run blk_update_request() and blk_mq_end_request() with bottom\\nhalves disabled. This forces blkdev_release() to run in kernel work-queue\\ncontext instead of current task work context, and allows ublk server to make\\nforward progress, and avoids the deadlock.\\n\\n[axboe: rewrite comment in ublk]\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0460e09a614291f06c008443f47393c37b7358e7\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c258f5c4502c9667bccf5d76fa731ab9c96687c1\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}