Linux Kernel DWC3 USB EndTransfer ForceRM Bit Misuse Causing SMMU Fault
CVE-2026-90030 Published on September 16, 2026
usb: dwc3: clear forceRM when issuing EndTransfer
In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: clear forceRM when issuing EndTransfer
The forceRM bit of the DEPCMD register controls the behavior of the
EndTransfer command used to stop an active transfer. Older DWC3
programming guide revisions recommended setting forceRM=1 when
issuing EndTransfer. Newer programming guide revisions recommend
issuing EndTransfer with forceRM cleared.
With forceRM=1 on DWC_usb31 v2.00a and v2.10a controllers, a transfer
aborted through the ep_dequeue path was observed to remain active
after EndTransfer completion. A subsequent StartTransfer issued on the
same endpoint triggered writes associated with the aborted transfer.
This resulted in an SMMU fault because the transfer buffer had already
been unmapped during EndTransfer command-completion cleanup.
Using forceRM=0 eliminates the issue. Although older DWC3 programming
guide revisions recommended setting forceRM=1, no issues are known
from using forceRM=0. Clear forceRM when issuing EndTransfer to provide
consistent EndTransfer behavior and align with newer programming guide
recommendations.
Products Associated with CVE-2026-90030
Want to know whenever a new CVE is published for Linux Kernel? stack.watch will email you.
Affected Versions
Linux:- Version 1e43c86d84fb0503e82a143e017f35421498fc1a and below 0afe5c31612de3d18cc6d16e616da4a48ba1e5a2 is affected.
- Version 1e43c86d84fb0503e82a143e017f35421498fc1a and below e01408ee52fe5cb2d0b43f47f359336af2b6c316 is affected.
- Version 1e43c86d84fb0503e82a143e017f35421498fc1a and below b58e6200450d350314db0ecda7d6d1bde3281e80 is affected.
- Version ab99c4be945724b032cc55e05c6738fe1d84bf70 is affected.
- Version 6.6.37 and below 6.7 is affected.
- Version 6.9 is affected.
- Before 6.9 is unaffected.
- Version 6.18.51, <= 6.18.* is unaffected.
- Version 7.2.5, <= 7.2.* is unaffected.
- Version 7.3-rc2, <= * is unaffected.