Vulnerability-Lookup

GHSA-JPH2-QVW9-VVWQ

Vulnerability from github – Published: 2026-05-06 12:30 – Updated: 2026-05-13 21:31

Details

In the Linux kernel, the following vulnerability has been resolved:

iommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode

PCIe endpoints with ATS enabled and passed through to userspace (e.g., QEMU, DPDK) can hard-lock the host when their link drops, either by surprise removal or by a link fault.

Commit 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected") adds pci_dev_is_disconnected() to devtlb_invalidation_with_pasid() so ATS invalidation is skipped only when the device is being safely removed, but it applies only when Intel IOMMU scalable mode is enabled.

With scalable mode disabled or unsupported, a system hard-lock occurs when a PCIe endpoint's link drops because the Intel IOMMU waits indefinitely for an ATS invalidation that cannot complete.

Call Trace: qi_submit_sync qi_flush_dev_iotlb __context_flush_dev_iotlb.part.0 domain_context_clear_one_cb pci_for_each_dma_alias device_block_translation blocking_domain_attach_dev iommu_deinit_device __iommu_group_remove_device iommu_release_device iommu_bus_notifier blocking_notifier_call_chain bus_notify device_del pci_remove_bus_device pci_stop_and_remove_bus_device pciehp_unconfigure_device pciehp_disable_slot pciehp_handle_presence_or_link_change pciehp_ist

Commit 81e921fd3216 ("iommu/vt-d: Fix NULL domain on device release") adds intel_pasid_teardown_sm_context() to intel_iommu_release_device(), which calls qi_flush_dev_iotlb() and can also hard-lock the system when a PCIe endpoint's link drops.

Call Trace: qi_submit_sync qi_flush_dev_iotlb __context_flush_dev_iotlb.part.0 intel_context_flush_no_pasid device_pasid_table_teardown pci_pasid_table_teardown pci_for_each_dma_alias intel_pasid_teardown_sm_context intel_iommu_release_device iommu_deinit_device __iommu_group_remove_device iommu_release_device iommu_bus_notifier blocking_notifier_call_chain bus_notify device_del pci_remove_bus_device pci_stop_and_remove_bus_device pciehp_unconfigure_device pciehp_disable_slot pciehp_handle_presence_or_link_change pciehp_ist

Sometimes the endpoint loses connection without a link-down event (e.g., due to a link fault); killing the process (virsh destroy) then hard-locks the host.

Call Trace: qi_submit_sync qi_flush_dev_iotlb __context_flush_dev_iotlb.part.0 domain_context_clear_one_cb pci_for_each_dma_alias device_block_translation blocking_domain_attach_dev __iommu_attach_device __iommu_device_set_domain __iommu_group_set_domain_internal iommu_detach_group vfio_iommu_type1_detach_group vfio_group_detach_container vfio_group_fops_release __fput

pci_dev_is_disconnected() only covers safe-removal paths; pci_device_is_present() tests accessibility by reading vendor/device IDs and internally calls pci_dev_is_disconnected(). On a ConnectX-5 (8 GT/s, x2) this costs ~70 µs.

Since __context_flush_dev_iotlb() is only called on {attach,release}_dev paths (not hot), add pci_device_is_present() there to skip inaccessible devices and avoid the hard-lock.

Severity

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-43161"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-06T12:16:34Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode\n\nPCIe endpoints with ATS enabled and passed through to userspace\n(e.g., QEMU, DPDK) can hard-lock the host when their link drops,\neither by surprise removal or by a link fault.\n\nCommit 4fc82cd907ac (\"iommu/vt-d: Don\u0027t issue ATS Invalidation\nrequest when device is disconnected\") adds pci_dev_is_disconnected()\nto devtlb_invalidation_with_pasid() so ATS invalidation is skipped\nonly when the device is being safely removed, but it applies only\nwhen Intel IOMMU scalable mode is enabled.\n\nWith scalable mode disabled or unsupported, a system hard-lock\noccurs when a PCIe endpoint\u0027s link drops because the Intel IOMMU\nwaits indefinitely for an ATS invalidation that cannot complete.\n\nCall Trace:\n qi_submit_sync\n qi_flush_dev_iotlb\n __context_flush_dev_iotlb.part.0\n domain_context_clear_one_cb\n pci_for_each_dma_alias\n device_block_translation\n blocking_domain_attach_dev\n iommu_deinit_device\n __iommu_group_remove_device\n iommu_release_device\n iommu_bus_notifier\n blocking_notifier_call_chain\n bus_notify\n device_del\n pci_remove_bus_device\n pci_stop_and_remove_bus_device\n pciehp_unconfigure_device\n pciehp_disable_slot\n pciehp_handle_presence_or_link_change\n pciehp_ist\n\nCommit 81e921fd3216 (\"iommu/vt-d: Fix NULL domain on device release\")\nadds intel_pasid_teardown_sm_context() to intel_iommu_release_device(),\nwhich calls qi_flush_dev_iotlb() and can also hard-lock the system\nwhen a PCIe endpoint\u0027s link drops.\n\nCall Trace:\n qi_submit_sync\n qi_flush_dev_iotlb\n __context_flush_dev_iotlb.part.0\n intel_context_flush_no_pasid\n device_pasid_table_teardown\n pci_pasid_table_teardown\n pci_for_each_dma_alias\n intel_pasid_teardown_sm_context\n intel_iommu_release_device\n iommu_deinit_device\n __iommu_group_remove_device\n iommu_release_device\n iommu_bus_notifier\n blocking_notifier_call_chain\n bus_notify\n device_del\n pci_remove_bus_device\n pci_stop_and_remove_bus_device\n pciehp_unconfigure_device\n pciehp_disable_slot\n pciehp_handle_presence_or_link_change\n pciehp_ist\n\nSometimes the endpoint loses connection without a link-down event\n(e.g., due to a link fault); killing the process (virsh destroy)\nthen hard-locks the host.\n\nCall Trace:\n qi_submit_sync\n qi_flush_dev_iotlb\n __context_flush_dev_iotlb.part.0\n domain_context_clear_one_cb\n pci_for_each_dma_alias\n device_block_translation\n blocking_domain_attach_dev\n __iommu_attach_device\n __iommu_device_set_domain\n __iommu_group_set_domain_internal\n iommu_detach_group\n vfio_iommu_type1_detach_group\n vfio_group_detach_container\n vfio_group_fops_release\n __fput\n\npci_dev_is_disconnected() only covers safe-removal paths;\npci_device_is_present() tests accessibility by reading\nvendor/device IDs and internally calls pci_dev_is_disconnected().\nOn a ConnectX-5 (8 GT/s, x2) this costs ~70 \u00b5s.\n\nSince __context_flush_dev_iotlb() is only called on\n{attach,release}_dev paths (not hot), add pci_device_is_present()\nthere to skip inaccessible devices and avoid the hard-lock.",
  "id": "GHSA-jph2-qvw9-vvwq",
  "modified": "2026-05-13T21:31:58Z",
  "published": "2026-05-06T12:30:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43161"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/42662d19839f34735b718129ea200e3734b07e50"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/48b3f08e68b29a79527869cdde7298ca2a9b9646"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bc0490ad9edf5c6f98e39fbbee2877b85261a5ae"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e70d5feb10c5ba2bbf7ca400b8f39a2f82d653e8"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-43161 (GCVE-0-2026-43161)

Vulnerability from cvelistv5 – Published: 2026-05-06 11:27 – Updated: 2026-05-23 16:06

Title

iommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode

Summary

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode PCIe endpoints with ATS enabled and passed through to userspace (e.g., QEMU, DPDK) can hard-lock the host when their link drops, either by surprise removal or by a link fault. Commit 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected") adds pci_dev_is_disconnected() to devtlb_invalidation_with_pasid() so ATS invalidation is skipped only when the device is being safely removed, but it applies only when Intel IOMMU scalable mode is enabled. With scalable mode disabled or unsupported, a system hard-lock occurs when a PCIe endpoint's link drops because the Intel IOMMU waits indefinitely for an ATS invalidation that cannot complete. Call Trace: qi_submit_sync qi_flush_dev_iotlb __context_flush_dev_iotlb.part.0 domain_context_clear_one_cb pci_for_each_dma_alias device_block_translation blocking_domain_attach_dev iommu_deinit_device __iommu_group_remove_device iommu_release_device iommu_bus_notifier blocking_notifier_call_chain bus_notify device_del pci_remove_bus_device pci_stop_and_remove_bus_device pciehp_unconfigure_device pciehp_disable_slot pciehp_handle_presence_or_link_change pciehp_ist Commit 81e921fd3216 ("iommu/vt-d: Fix NULL domain on device release") adds intel_pasid_teardown_sm_context() to intel_iommu_release_device(), which calls qi_flush_dev_iotlb() and can also hard-lock the system when a PCIe endpoint's link drops. Call Trace: qi_submit_sync qi_flush_dev_iotlb __context_flush_dev_iotlb.part.0 intel_context_flush_no_pasid device_pasid_table_teardown pci_pasid_table_teardown pci_for_each_dma_alias intel_pasid_teardown_sm_context intel_iommu_release_device iommu_deinit_device __iommu_group_remove_device iommu_release_device iommu_bus_notifier blocking_notifier_call_chain bus_notify device_del pci_remove_bus_device pci_stop_and_remove_bus_device pciehp_unconfigure_device pciehp_disable_slot pciehp_handle_presence_or_link_change pciehp_ist Sometimes the endpoint loses connection without a link-down event (e.g., due to a link fault); killing the process (virsh destroy) then hard-locks the host. Call Trace: qi_submit_sync qi_flush_dev_iotlb __context_flush_dev_iotlb.part.0 domain_context_clear_one_cb pci_for_each_dma_alias device_block_translation blocking_domain_attach_dev __iommu_attach_device __iommu_device_set_domain __iommu_group_set_domain_internal iommu_detach_group vfio_iommu_type1_detach_group vfio_group_detach_container vfio_group_fops_release __fput pci_dev_is_disconnected() only covers safe-removal paths; pci_device_is_present() tests accessibility by reading vendor/device IDs and internally calls pci_dev_is_disconnected(). On a ConnectX-5 (8 GT/s, x2) this costs ~70 µs. Since __context_flush_dev_iotlb() is only called on {attach,release}_dev paths (not hot), add pci_device_is_present() there to skip inaccessible devices and avoid the hard-lock.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/48b3f08e68b29a795…
https://git.kernel.org/stable/c/e70d5feb10c5ba2bb…
https://git.kernel.org/stable/c/bc0490ad9edf5c6f9…
https://git.kernel.org/stable/c/42662d19839f34735…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 37764b952e1b39053defc7ebe5dcd8c4e3e78de9 , < 48b3f08e68b29a79527869cdde7298ca2a9b9646 (git) Affected: 37764b952e1b39053defc7ebe5dcd8c4e3e78de9 , < e70d5feb10c5ba2bbf7ca400b8f39a2f82d653e8 (git) Affected: 37764b952e1b39053defc7ebe5dcd8c4e3e78de9 , < bc0490ad9edf5c6f98e39fbbee2877b85261a5ae (git) Affected: 37764b952e1b39053defc7ebe5dcd8c4e3e78de9 , < 42662d19839f34735b718129ea200e3734b07e50 (git) Affected: 99301a53a1378f8863ac7850b9589f997bb0e125 (git) Affected: 948ec6d003280d49aca49b366aa5cb140f87434d (git) Affected: 5.12.19 , < 5.13 (semver) Affected: 5.13.4 , < 5.14 (semver)
Linux	Linux	Affected: 5.14 Unaffected: 0 , < 5.14 (semver) Unaffected: 6.12.77 , ≤ 6.12.* (semver) Unaffected: 6.18.17 , ≤ 6.18.* (semver) Unaffected: 6.19.6 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/iommu/intel/pasid.c"
          ],
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          "vendor": "Linux",
          "versions": [
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              "lessThan": "48b3f08e68b29a79527869cdde7298ca2a9b9646",
              "status": "affected",
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              "versionType": "git"
            },
            {
              "lessThan": "e70d5feb10c5ba2bbf7ca400b8f39a2f82d653e8",
              "status": "affected",
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            {
              "status": "affected",
              "version": "99301a53a1378f8863ac7850b9589f997bb0e125",
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              "status": "unaffected",
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              "versionType": "semver"
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              "status": "unaffected",
              "version": "6.12.77",
              "versionType": "semver"
            },
            {
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              "status": "unaffected",
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              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
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                  "vulnerable": true
                },
                {
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode\n\nPCIe endpoints with ATS enabled and passed through to userspace\n(e.g., QEMU, DPDK) can hard-lock the host when their link drops,\neither by surprise removal or by a link fault.\n\nCommit 4fc82cd907ac (\"iommu/vt-d: Don\u0027t issue ATS Invalidation\nrequest when device is disconnected\") adds pci_dev_is_disconnected()\nto devtlb_invalidation_with_pasid() so ATS invalidation is skipped\nonly when the device is being safely removed, but it applies only\nwhen Intel IOMMU scalable mode is enabled.\n\nWith scalable mode disabled or unsupported, a system hard-lock\noccurs when a PCIe endpoint\u0027s link drops because the Intel IOMMU\nwaits indefinitely for an ATS invalidation that cannot complete.\n\nCall Trace:\n qi_submit_sync\n qi_flush_dev_iotlb\n __context_flush_dev_iotlb.part.0\n domain_context_clear_one_cb\n pci_for_each_dma_alias\n device_block_translation\n blocking_domain_attach_dev\n iommu_deinit_device\n __iommu_group_remove_device\n iommu_release_device\n iommu_bus_notifier\n blocking_notifier_call_chain\n bus_notify\n device_del\n pci_remove_bus_device\n pci_stop_and_remove_bus_device\n pciehp_unconfigure_device\n pciehp_disable_slot\n pciehp_handle_presence_or_link_change\n pciehp_ist\n\nCommit 81e921fd3216 (\"iommu/vt-d: Fix NULL domain on device release\")\nadds intel_pasid_teardown_sm_context() to intel_iommu_release_device(),\nwhich calls qi_flush_dev_iotlb() and can also hard-lock the system\nwhen a PCIe endpoint\u0027s link drops.\n\nCall Trace:\n qi_submit_sync\n qi_flush_dev_iotlb\n __context_flush_dev_iotlb.part.0\n intel_context_flush_no_pasid\n device_pasid_table_teardown\n pci_pasid_table_teardown\n pci_for_each_dma_alias\n intel_pasid_teardown_sm_context\n intel_iommu_release_device\n iommu_deinit_device\n __iommu_group_remove_device\n iommu_release_device\n iommu_bus_notifier\n blocking_notifier_call_chain\n bus_notify\n device_del\n pci_remove_bus_device\n pci_stop_and_remove_bus_device\n pciehp_unconfigure_device\n pciehp_disable_slot\n pciehp_handle_presence_or_link_change\n pciehp_ist\n\nSometimes the endpoint loses connection without a link-down event\n(e.g., due to a link fault); killing the process (virsh destroy)\nthen hard-locks the host.\n\nCall Trace:\n qi_submit_sync\n qi_flush_dev_iotlb\n __context_flush_dev_iotlb.part.0\n domain_context_clear_one_cb\n pci_for_each_dma_alias\n device_block_translation\n blocking_domain_attach_dev\n __iommu_attach_device\n __iommu_device_set_domain\n __iommu_group_set_domain_internal\n iommu_detach_group\n vfio_iommu_type1_detach_group\n vfio_group_detach_container\n vfio_group_fops_release\n __fput\n\npci_dev_is_disconnected() only covers safe-removal paths;\npci_device_is_present() tests accessibility by reading\nvendor/device IDs and internally calls pci_dev_is_disconnected().\nOn a ConnectX-5 (8 GT/s, x2) this costs ~70 \u00b5s.\n\nSince __context_flush_dev_iotlb() is only called on\n{attach,release}_dev paths (not hot), add pci_device_is_present()\nthere to skip inaccessible devices and avoid the hard-lock."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-23T16:06:27.637Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/48b3f08e68b29a79527869cdde7298ca2a9b9646"
        },
        {
          "url": "https://git.kernel.org/stable/c/e70d5feb10c5ba2bbf7ca400b8f39a2f82d653e8"
        },
        {
          "url": "https://git.kernel.org/stable/c/bc0490ad9edf5c6f98e39fbbee2877b85261a5ae"
        },
        {
          "url": "https://git.kernel.org/stable/c/42662d19839f34735b718129ea200e3734b07e50"
        }
      ],
      "title": "iommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43161",
    "datePublished": "2026-05-06T11:27:39.881Z",
    "dateReserved": "2026-05-01T14:12:55.990Z",
    "dateUpdated": "2026-05-23T16:06:27.637Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.