iommu/vt-d: Fix UAF on sva unbind with pending IOPFs

{
  "id": "8fd2ad4163f81e0f0714963ce368ec8d1bc7584a3a4960ce7f436f295822be48",
  "url": "https://osv.dev/vulnerability/CVE-2025-38594",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "iommu/vt-d: Fix UAF on sva unbind with pending IOPFs",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix UAF on sva unbind with pending IOPFs Commit 17fce9d2336d (\"iommu/vt-d: Put iopf enablement in domain attach path\") disables IOPF on device by removing the device from its IOMMU's IOPF queue when the last IOPF-capable domain is detached from the device. Unfortunately, it did this in a wrong place where there are still pending IOPFs. As a result, a use-after-free error is potentially triggered and eventually a kernel panic with a kernel trace similar to the following: refcount_t: underflow; use-after-free. WARNING: CPU: 3 PID: 313 at lib/refcount.c:28 refcount_warn_saturate+0xd8/0xe0 Workqueue: iopf_queue/dmar0-iopfq iommu_sva_handle_iopf Call Trace: iopf_free_group+0xe/0x20 process_one_work+0x197/0x3d0 worker_thread+0x23a/0x350 ? rescuer_thread+0x4a0/0x4a0 kthread+0xf8/0x230 ? finish_task_switch.isra.0+0x81/0x260 ? kthreads_online_cpu+0x110/0x110 ? kthreads_online_cpu+0x110/0x110 ret_from_fork+0x13b/0x170 ? kthreads_online_cpu+0x110/0x110 ret_from_fork_asm+0x11/0x20 ---[ end trace 0000000000000000 ]--- The intel_pasid_tear_down_entry() function is responsible for blocking hardware from generating new page faults and flushing all in-flight ones. Therefore, moving iopf_for_domain_remove() after this function should resolve this.",
    "evidence": "osv:CVE-2025-38594",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.16.1",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2025-38594",
      "aliases": [
        "CVE-2025-38594"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                  "introduced": "17fce9d2336d952b95474248303e5e7d9777f2e0"
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                {
                  "fixed": "c68332b7ee893292bba6e87d31ef2080c066c65d"
                },
                {
                  "fixed": "f0b9d31c6edd50a6207489cd1bd4ddac814b9cd2"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-38594.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.16.0"
                },
                {
                  "fixed": "6.16.1"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-38594.json"
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        }
      ],
      "modified": "2026-10-28T02:30:51.559168217Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/c68332b7ee893292bba6e87d31ef2080c066c65d",
        "https://git.kernel.org/stable/c/f0b9d31c6edd50a6207489cd1bd4ddac814b9cd2",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/38xxx/CVE-2025-38594.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-38594",
        "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/2025/38xxx/CVE-2025-38594.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-38594",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 520124,
  "published_at": "2025-08-19T17:03:19.689+00:00"
}