In the Linux kernel, the following vulnerability has been resolved:
iommu/amd: Put PCI device after handling PPR faults
iommu_call_iopf_notifier() looks up the requester with
pci_get_domain_bus_and_slot(), which returns a PCI device with its
reference count incremented.
Neither the successful iommu_report_device_fault() path nor the abort
path drops that reference, so every handled PPR request leaks a PCI
device reference.
This is the same ownership rule that was fixed for the old iommu_v2
ppr_notifier() path by commit 6cf0981c2233 (“iommu/amd: Fix pci device
refcount leak in ppr_notifier()”), but iommu_call_iopf_notifier() was
added later as a separate PPR/IOPF notifier path.
Drop the PCI device reference after handling the PPR entry.
