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.
Metrics
Affected Vendors & Products
References
History
Wed, 19 Mar 2025 16:45:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Linux
Linux linux Kernel |
|
CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:* |
|
Vendors & Products |
Linux
Linux linux Kernel |
Thu, 07 Nov 2024 17:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Metrics |
cvssV3_1
|
cvssV3_1
|

Status: PUBLISHED
Assigner: Linux
Published: 2024-03-25T09:07:38.949Z
Updated: 2024-12-19T07:35:59.477Z
Reserved: 2024-03-04T18:12:48.842Z
Link: CVE-2021-47140

Updated: 2024-08-04T05:24:39.961Z

Status : Analyzed
Published: 2024-03-25T09:15:08.740
Modified: 2025-03-19T16:28:16.000
Link: CVE-2021-47140
