microdroid/sepolicy/system/private/kernel.te

typeattribute kernel coredomain;

domain_auto_trans(kernel, init_exec, init)
domain_auto_trans(kernel, snapuserd_exec, snapuserd)

# Allow the kernel to read otapreopt_chroot's file descriptors and files under
# /postinstall, as it uses apexd logic to mount APEX packages in /postinstall/apex.
allow kernel otapreopt_chroot:fd use;
allow kernel postinstall_file:file read;

# The following sections are for the transition period during a Virtual A/B
# OTA. Once sepolicy is loaded, snapuserd must be re-launched in the correct
# context, and with properly labelled devices. This must be done before
# enabling enforcement, eg, in permissive mode while still in the kernel
# context.
allow kernel tmpfs:blk_file { getattr relabelfrom };
allow kernel tmpfs:chr_file { getattr relabelfrom };
allow kernel tmpfs:lnk_file { getattr relabelfrom };
allow kernel tmpfs:dir { open read relabelfrom };

allow kernel block_device:blk_file relabelto;
allow kernel block_device:lnk_file relabelto;
allow kernel dm_device:chr_file relabelto;
allow kernel dm_device:blk_file relabelto;
allow kernel dm_user_device:dir { read open search relabelto };
allow kernel dm_user_device:chr_file relabelto;
allow kernel kmsg_device:chr_file relabelto;
allow kernel null_device:chr_file relabelto;
allow kernel random_device:chr_file relabelto;
allow kernel snapuserd_exec:file relabelto;
allow kernel vd_device:blk_file read;

allow kernel kmsg_device:chr_file write;
allow kernel gsid:fd use;

# apkdmverity attaches a loop device to idsig file
# and the loop device is used by zipfuse later.
# This requires kernel to use the fd opened by apkdmverity.
allow kernel apkdmverity:fd use;