{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "fd22aef8b47cfc068448df65c1183698b0abd815"
            },
            {
              "fixed": "3427d7ae38337066ce88b68302e285d344ab756b"
            },
            {
              "fixed": "9dcd4f5c99b491c37be90b0bd9988db48225fb75"
            },
            {
              "fixed": "9400efc76b42c751211974a25c91d2c19c65b01b"
            },
            {
              "fixed": "9fc75b71fdd38465c76c6f6a884cdd4ae3c72d90"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.12.0"
            },
            {
              "fixed": "6.12.92"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.34"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64112.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nrbd: eliminate a race in lock_dwork draining on unmap\n\nGiven how rbd_lock_add_request() and rbd_img_exclusive_lock() are\nwritten, lock_dwork may be (re)queued more than it's actually needed:\nfor example in case a new I/O request comes in while we are in the\nmiddle of rbd_acquire_lock() on behalf of another I/O request.  This is\nexpected and with rbd_release_lock() preemptively canceling lock_dwork\nis benign under normal operation.\n\nA more problematic example is maybe_kick_acquire():\n\n    if (have_requests || delayed_work_pending(\u0026rbd_dev-\u003elock_dwork)) {\n            dout(\"%s rbd_dev %p kicking lock_dwork\\n\", __func__, rbd_dev);\n            mod_delayed_work(rbd_dev-\u003etask_wq, \u0026rbd_dev-\u003elock_dwork, 0);\n    }\n\nIt's not unrealistic for lock_dwork to get canceled right after\ndelayed_work_pending() returns true and for mod_delayed_work() to\nrequeue it right there anyway.  This is a classic TOCTOU race.\n\nWhen it comes to unmapping the image, there is an implicit assumption\nof no self-initiated exclusive lock activity past the point of return\nfrom rbd_dev_image_unlock() which unlocks the lock if it happens to be\nheld.  This unlock is assumed to be final and lock_dwork (as well as\nall other exclusive lock tasks, really) isn't expected to get queued\nagain.  However, lock_dwork is canceled only in cancel_tasks_sync()\n(i.e. later in the unmap sequence) and on top of that the cancellation\ncan get in effect nullified by maybe_kick_acquire().  This may result\nin rbd_acquire_lock() executing after rbd_dev_device_release() and\nrbd_dev_image_release() run and free and/or reset a bunch of things.\nOne of the possible failure modes then is a violated\n\n    rbd_assert(rbd_image_format_valid(rbd_dev-\u003eimage_format));\n\nin rbd_dev_header_info() which is called via rbd_dev_refresh() from\nrbd_post_acquire_action().\n\nRedo exclusive lock task draining to provide saner semantics and try\nto meet the assumptions around rbd_dev_image_unlock().",
  "id": "CVE-2026-64112",
  "modified": "2026-08-14T03:51:38.054377156Z",
  "published": "2026-07-19T15:40:13.652Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3427d7ae38337066ce88b68302e285d344ab756b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9400efc76b42c751211974a25c91d2c19c65b01b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9dcd4f5c99b491c37be90b0bd9988db48225fb75"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9fc75b71fdd38465c76c6f6a884cdd4ae3c72d90"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64112.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64112"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "rbd: eliminate a race in lock_dwork draining on unmap"
}