CVE-2021-47140
- Source
- https://cve.org/CVERecord?id=CVE-2021-47140
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47140.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2021-47140
- Downstream
- Published
- 2024-03-25T09:15:08Z
- Modified
- 2026-03-14T14:59:04Z
- Severity
-
- 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L CVSS Calculator
- Summary
- [none]
- Details
-
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.
- References
Affected packages
Git /
Database specific
source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47140.json"
unresolved_ranges
[
{
"events": [
{
"introduced": "5.11"
},
{
"fixed": "5.12.9"
}
]
},
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "5.13-rc1"
}
]
},
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "5.13-rc2"
}
]
},
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "5.13-rc3"
}
]
}
]