{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "441244d4273a8037b265fd254dfdaca5fa736ee2"
            },
            {
              "fixed": "6debde9e3e6ae21dcca75837b4247b13ca4ea2b8"
            },
            {
              "fixed": "3674f780f47d2906b5a0f7199b66973067bdfeca"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89546.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: close backchannel before destroying callback service\n\nA backchannel receive can complete a request while the NFS callback\nservice is being torn down.  xprt_complete_bc_request() removes the\nrequest from bc_pa_list, drops bc_alloc_count, marks the request in use,\nand then asks xprt_enqueue_bc_request() to hand it to the callback\nservice.\n\nIf teardown has already cleared xprt-\u003ebc_serv, xprt_enqueue_bc_request()\ncurrently returns without enqueueing or freeing the committed request.\nThe xprt_get() taken on entry is leaked as well.  If the producer wins\nthe race before bc_serv is cleared, it can also enqueue onto sv_cb_list\nafter nfs_callback_down() has stopped the callback threads, leaving the\nrequest linked to a svc_serv that is about to be freed.\n\nClose the producer side before callback threads are stopped.  Add\nxprt_svc_shutdown_bc() to clear xprt-\u003ebc_serv under bc_pa_lock, and call\nit on callback shutdown and callback-start failure before stopping the\nservice threads.  Requests that lose the NULL transition in\nxprt_enqueue_bc_request() are released through the normal backchannel\nfree path after balancing bc_slot_count.  Finally, drain any remaining\nsv_cb_list requests after the callback threads have stopped and before\nsvc_destroy() frees the service.",
  "id": "CVE-2026-89546",
  "modified": "2026-09-15T03:30:48.337302238Z",
  "published": "2026-09-11T19:44:21.898Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3674f780f47d2906b5a0f7199b66973067bdfeca"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6debde9e3e6ae21dcca75837b4247b13ca4ea2b8"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89546.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89546"
    },
    {
      "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:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "SUNRPC: close backchannel before destroying callback service"
}