In the Linux kernel, the following vulnerability has been resolved:
iommu/s390: Implement blocking domain
This fixes a crash when surprise hot-unplugging a PCI device. This crash happens because during hot-unplug _iommugroupsetdomainnofail() attaching the default domain fails when the platform no longer recognizes the device as it has already been removed and we end up with a NULL domain pointer and UAF. This is exactly the case referred to in the second comment in _iommudeviceset_domain() and just as stated there if we can instead attach the blocking domain the UAF is prevented as this can handle the already removed device. Implement the blocking domain to use this handling. With this change, the crash is fixed but we still hit a warning attempting to change DMA ownership on a blocked device.