CVE-2021-47140 (GCVE-0-2021-47140)

Vulnerability from cvelistv5 – Published: 2024-03-25 09:07 – Updated: 2026-05-11 13:48
VLAI?
Title
iommu/amd: Clear DMA ops when switching domain
Summary
In the Linux kernel, the following vulnerability has been resolved: iommu/amd: Clear DMA ops when switching domain Since commit 08a27c1c3ecf ("iommu: Add support to change default domain of an iommu group") a user can switch a device between IOMMU and direct DMA through sysfs. This doesn't work for AMD IOMMU at the moment because dev->dma_ops is not cleared when switching from a DMA to an identity IOMMU domain. The DMA layer thus attempts to use the dma-iommu ops on an identity domain, causing an oops: # echo 0000:00:05.0 > /sys/sys/bus/pci/drivers/e1000e/unbind # echo identity > /sys/bus/pci/devices/0000:00:05.0/iommu_group/type # echo 0000:00:05.0 > /sys/sys/bus/pci/drivers/e1000e/bind ... BUG: kernel NULL pointer dereference, address: 0000000000000028 ... Call Trace: iommu_dma_alloc e1000e_setup_tx_resources e1000e_open Since iommu_change_dev_def_domain() calls probe_finalize() again, clear the dma_ops there like Vt-d does.
Severity ?
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 08a27c1c3ecf5e1da193ce5f8fc97c3be16e75f0 , < f3f2cf46291a693eab21adb94171b0128c2a9ec1 (git)
Affected: 08a27c1c3ecf5e1da193ce5f8fc97c3be16e75f0 , < d6177a6556f853785867e2ec6d5b7f4906f0d809 (git)
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Linux Linux Affected: 5.11
Unaffected: 0 , < 5.11 (semver)
Unaffected: 5.12.9 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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    "vulnrichment": {
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      "cveMetadata": "{\"cveId\": \"CVE-2021-47140\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2024-12-19T07:35:59.477Z\", \"dateReserved\": \"2024-03-04T18:12:48.842Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2024-03-25T09:07:38.949Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}


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Taxonomy of the tags.




Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.