platform_system_sepolicy/private/vfio_handler.te

is_flag_enabled(RELEASE_AVF_ENABLE_DEVICE_ASSIGNMENT, `
    # vfio_handler is a helper service for VFIO tasks, like binding platform devices to VFIO driver.
    # vfio_handler is separate from virtualizationservice as VFIO tasks require root.
    type vfio_handler, domain, coredomain;
    type vfio_handler_exec, system_file_type, exec_type, file_type;

    # When init runs a file labelled with vfio_handler_exec, run it in the vfio_handler domain.
    init_daemon_domain(vfio_handler)

    # Let the vfio_handler domain register the vfio_handler_service with ServiceManager.
    add_service(vfio_handler, vfio_handler_service)

    # Let the vfio_handler domain use Binder.
    binder_use(vfio_handler)

    # Allow vfio_handler to check if VFIO is supported
    allow vfio_handler vfio_device:chr_file getattr;
    allow vfio_handler vfio_device:dir r_dir_perms;

    # Allow vfio_handler to bind/unbind platform devices
    allow vfio_handler sysfs:dir r_dir_perms;
    allow vfio_handler sysfs:file rw_file_perms;

    # Allow vfio_handler to write to VM DTBO via a file created by virtualizationservice.
    allow vfio_handler virtualizationservice:fd use;
    allow vfio_handler virtualizationservice_data_file:file write;

    # vfio_handler can only use fd from virtualizationservice, and cannot open files itself
    neverallow vfio_handler virtualizationservice_data_file:file { open create };

    # Allow vfio_handler to search /dev/block for accessing dtbo.img
    allow vfio_handler block_device:dir search;
    allow vfio_handler dtbo_block_device:blk_file r_file_perms;

    # Only vfio_handler can add vfio_handler_service
    neverallow { domain -vfio_handler } vfio_handler_service:service_manager add;
') # is_flag_enabled(RELEASE_AVF_ENABLE_DEVICE_ASSIGNMENT)