cbcvebase.
CVE-2021-47140
published 2024-03-25

CVE-2021-47140: In the Linux kernel, the following vulnerability has been resolved: iommu/amd: Clear DMA ops when switching domain Since commit 08a27c1c3ecf ("iommu: Add…

PriorityP426medium5.3CVSS 3.1
AVNACLPRNUINSUCNINAL
EPSS
0.60%
45.5th percentile
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.

Affected

9 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.14.6-1 (bookworm)linux 5.14.6-1 (bookworm)
linuxlinux
linuxlinux>= 08a27c1c3ecf5e1da193ce5f8fc97c3be16e75f0 < f3f2cf46291a693eab21adb94171b0128c2a9ec1f3f2cf46291a693eab21adb94171b0128c2a9ec1
linuxlinux>= 08a27c1c3ecf5e1da193ce5f8fc97c3be16e75f0 < d6177a6556f853785867e2ec6d5b7f4906f0d809d6177a6556f853785867e2ec6d5b7f4906f0d809
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 5.11 < 5.12.95.12.9

CVSS provenance

nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
osv5.3MEDIUM
vendor_debian5.3MEDIUM
vendor_redhat5.3MEDIUM
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