iommu/vt-d: Avoid format string leaks into iommu_device_create

This makes sure it won't be possible to accidentally leak format
strings into iommu device names. Current name allocations are safe,
but this makes the "%s" explicit.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/dmar.c

@@ -1068,7 +1068,7 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd)
 	if (intel_iommu_enabled)
 		iommu->iommu_dev = iommu_device_create(NULL, iommu,
 						       intel_iommu_groups,
-						       iommu->name);
+						       "%s", iommu->name);
 
 	return 0;
 

drivers/iommu/intel-iommu.c

@@ -4533,7 +4533,7 @@ int __init intel_iommu_init(void)
 	for_each_active_iommu(iommu, drhd)
 		iommu->iommu_dev = iommu_device_create(NULL, iommu,
 						       intel_iommu_groups,
-						       iommu->name);
+						       "%s", iommu->name);
 
 	bus_set_iommu(&pci_bus_type, &intel_iommu_ops);
 	bus_register_notifier(&pci_bus_type, &device_nb);