# init is its own domain. type init, domain, mlstrustedsubject; # The init domain is entered by execing init. type init_exec, exec_type, file_type; # /dev/__null__ node created by init. allow init tmpfs:chr_file { create setattr unlink rw_file_perms }; # # init direct restorecon calls. # # /dev/kmsg allow init tmpfs:chr_file relabelfrom; allow init kmsg_device:chr_file { write relabelto }; # /dev/__properties__ allow init properties_device:dir relabelto; allow init properties_serial:file { write relabelto }; allow init property_type:file { create_file_perms relabelto }; # /dev/event-log-tags allow init device:file relabelfrom; allow init runtime_event_log_tags_file:file { open write setattr relabelto }; # /dev/socket allow init { device socket_device }:dir relabelto; # /dev/random, /dev/urandom allow init random_device:chr_file relabelto; # /dev/device-mapper, /dev/block(/.*)? allow init tmpfs:{ chr_file blk_file } relabelfrom; allow init tmpfs:blk_file getattr; allow init block_device:{ dir blk_file lnk_file } relabelto; allow init dm_device:{ chr_file blk_file } relabelto; allow init kernel:fd use; # restorecon for early mount device symlinks allow init tmpfs:lnk_file { getattr read relabelfrom }; allow init system_block_device:{ blk_file lnk_file } relabelto; # setrlimit allow init self:capability sys_resource; # Remove /dev/.booting, created before initial policy load or restorecon /dev. allow init tmpfs:file unlink; # Access pty created for fsck. allow init devpts:chr_file { read write open }; # Create /dev/fscklogs files. allow init fscklogs:file create_file_perms; # Access /dev/__null__ node created prior to initial policy load. allow init tmpfs:chr_file write; # Access /dev/console. allow init console_device:chr_file rw_file_perms; # Access /dev/tty0. allow init tty_device:chr_file rw_file_perms; # Call mount(2). allow init self:capability sys_admin; # Create and mount on directories in /. allow init rootfs:dir create_dir_perms; allow init { rootfs cache_file cgroup storage_file system_data_file system_file vendor_file postinstall_mnt_dir }:dir mounton; # Mount on /dev/usb-ffs/adb. allow init device:dir mounton; # Create and remove symlinks in /. allow init rootfs:lnk_file { create unlink }; # Mount debugfs on /sys/kernel/debug. allow init sysfs:dir mounton; # Create cgroups mount points in tmpfs and mount cgroups on them. allow init tmpfs:dir create_dir_perms; allow init tmpfs:dir mounton; allow init cgroup:dir create_dir_perms; r_dir_file(init, cgroup) allow init cpuctl_device:dir { create mounton }; # /config allow init configfs:dir mounton; allow init configfs:dir create_dir_perms; # Use tmpfs as /data, used for booting when /data is encrypted allow init tmpfs:dir relabelfrom; # Create directories under /dev/cpuctl after chowning it to system. allow init self:capability dac_override; # Set system clock. allow init self:capability sys_time; allow init self:capability { sys_rawio mknod }; # Mounting filesystems from block devices. allow init dev_type:blk_file r_file_perms; # Mounting filesystems. # Only allow relabelto for types used in context= mount options, # which should all be assigned the contextmount_type attribute. # This can be done in device-specific policy via type or typeattribute # declarations. allow init fs_type:filesystem ~relabelto; allow init unlabeled:filesystem ~relabelto; allow init contextmount_type:filesystem relabelto; # Allow read-only access to context= mounted filesystems. allow init contextmount_type:dir r_dir_perms; allow init contextmount_type:notdevfile_class_set r_file_perms; # restorecon /adb_keys or any other rootfs files and directories to a more # specific type. allow init rootfs:{ dir file } relabelfrom; # mkdir, symlink, write, rm/rmdir, chown/chmod, restorecon/restorecon_recursive from init.rc files. # chown/chmod require open+read+setattr required for open()+fchown/fchmod(). # system/core/init.rc requires at least cache_file and data_file_type. # init..rc files often include device-specific types, so # we just allow all file types except /system files here. allow init self:capability { chown fowner fsetid }; allow init { file_type -app_data_file -exec_type -misc_logd_file -system_app_data_file -system_file -vendor_file_type }:dir { create search getattr open read setattr ioctl }; allow init { file_type -app_data_file -exec_type -keystore_data_file -misc_logd_file -shell_data_file -system_app_data_file -system_file -vendor_file_type -vold_data_file }:dir { write add_name remove_name rmdir relabelfrom }; allow init { file_type -app_data_file -runtime_event_log_tags_file -exec_type -keystore_data_file -misc_logd_file -shell_data_file -system_app_data_file -system_file -vendor_file_type -vold_data_file }:file { create getattr open read write setattr relabelfrom unlink }; allow init { file_type -app_data_file -exec_type -keystore_data_file -misc_logd_file -shell_data_file -system_app_data_file -system_file -vendor_file_type -vold_data_file }:{ sock_file fifo_file } { create getattr open read setattr relabelfrom unlink }; allow init { file_type -app_data_file -exec_type -keystore_data_file -misc_logd_file -shell_data_file -system_app_data_file -system_file -vendor_file_type -vold_data_file }:lnk_file { create getattr setattr relabelfrom unlink }; allow init cache_file:lnk_file r_file_perms; allow init { file_type -system_file -vendor_file_type -exec_type }:dir_file_class_set relabelto; allow init { sysfs debugfs debugfs_tracing }:{ dir file lnk_file } { getattr relabelfrom }; allow init { sysfs_type debugfs_type }:{ dir file lnk_file } { relabelto getattr }; allow init dev_type:dir create_dir_perms; allow init dev_type:lnk_file create; # Disable tracing by writing to /sys/kernel/debug/tracing/tracing_on allow init tracing_shell_writable:file w_file_perms; # Setup and control wifi event tracing (see wifi-events.rc) allow init debugfs_tracing_instances:dir create_dir_perms; allow init debugfs_tracing_instances:file w_file_perms; allow init debugfs_wifi_tracing:file w_file_perms; # chown/chmod on pseudo files. allow init { fs_type -contextmount_type -sdcard_type -rootfs }:file { open read setattr }; allow init { fs_type -contextmount_type -sdcard_type -rootfs }:dir { open read setattr search }; # init should not be able to read or open generic devices # TODO: auditing to see if this can be deleted entirely allow init { dev_type -kmem_device -port_device -device }:chr_file { read open }; auditallow init { dev_type -alarm_device -ashmem_device -binder_device -console_device -device -devpts -dm_device -hwbinder_device -hw_random_device -keychord_device -kmem_device -kmsg_device -null_device -owntty_device -port_device -ptmx_device -random_device -zero_device }:chr_file { read open }; # chown/chmod on devices. allow init { dev_type -kmem_device -port_device }:chr_file setattr; # Unlabeled file access for upgrades from 4.2. allow init unlabeled:dir { create_dir_perms relabelfrom }; allow init unlabeled:notdevfile_class_set { create_file_perms relabelfrom }; # Any operation that can modify the kernel ring buffer, e.g. clear # or a read that consumes the messages that were read. allow init kernel:system syslog_mod; allow init self:capability2 syslog; # Set usermodehelpers and /proc security settings. allow init usermodehelper:file rw_file_perms; allow init proc_security:file rw_file_perms; # Write to /proc/sys/kernel/panic_on_oops. r_dir_file(init, proc) allow init proc:file w_file_perms; # Write to /proc/sys/net/ping_group_range and other /proc/sys/net files. r_dir_file(init, proc_net) allow init proc_net:file w_file_perms; allow init self:capability net_admin; # Write to /proc/sysrq-trigger. allow init proc_sysrq:file w_file_perms; # Read /proc/stat for bootchart. allow init proc_stat:file r_file_perms; # Reboot. allow init self:capability sys_boot; # Write to sysfs nodes. allow init sysfs_type:dir r_dir_perms; allow init sysfs_type:lnk_file read; allow init sysfs_type:file rw_file_perms; # Init will create /data/misc/logd when the property persist.logd.logpersistd is "logcatd". # Init will also walk through the directory as part of a recursive restorecon. allow init misc_logd_file:dir { add_name open create read getattr setattr search write }; allow init misc_logd_file:file { open create getattr setattr write }; # Support "adb shell stop" allow init self:capability kill; allow init domain:process { sigkill signal }; # Init creates keystore's directory on boot, and walks through # the directory as part of a recursive restorecon. allow init keystore_data_file:dir { open create read getattr setattr search }; allow init keystore_data_file:file { getattr }; # Init creates vold's directory on boot, and walks through # the directory as part of a recursive restorecon. allow init vold_data_file:dir { open create read getattr setattr search }; allow init vold_data_file:file { getattr }; # Init creates /data/local/tmp at boot allow init shell_data_file:dir { open create read getattr setattr search }; allow init shell_data_file:file { getattr }; # Set UID, GID, and adjust capability bounding set for services. allow init self:capability { setuid setgid setpcap }; # For bootchart to read the /proc/$pid/cmdline file of each process, # we need to have following line to allow init to have access # to different domains. r_dir_file(init, domain) # Use setexeccon(), setfscreatecon(), and setsockcreatecon(). # setexec is for services with seclabel options. # setfscreate is for labeling directories and socket files. # setsockcreate is for labeling local/unix domain sockets. allow init self:process { setexec setfscreate setsockcreate }; # Get file context allow init file_contexts_file:file r_file_perms; # sepolicy access allow init sepolicy_file:file r_file_perms; # Perform SELinux access checks on setting properties. selinux_check_access(init) # Ask the kernel for the new context on services to label their sockets. allow init kernel:security compute_create; # Create sockets for the services. allow init domain:unix_stream_socket { create bind }; allow init domain:unix_dgram_socket { create bind }; # Create /data/property and files within it. allow init property_data_file:dir create_dir_perms; allow init property_data_file:file create_file_perms; # Set any property. allow init property_type:property_service set; # Send an SELinux userspace denial to the kernel audit subsystem, # so it can be picked up and processed by logd. These denials are # generated when an attempt to set a property is denied by policy. allow init self:netlink_audit_socket { create_socket_perms_no_ioctl nlmsg_relay }; allow init self:capability audit_write; # Run "ifup lo" to bring up the localhost interface allow init self:udp_socket { create ioctl }; # in addition to unpriv ioctls granted to all domains, init also needs: allowxperm init self:udp_socket ioctl SIOCSIFFLAGS; allow init self:capability net_raw; # This line seems suspect, as it should not really need to # set scheduling parameters for a kernel domain task. allow init kernel:process setsched; # swapon() needs write access to swap device # system/core/fs_mgr/fs_mgr.c - fs_mgr_swapon_all allow init swap_block_device:blk_file rw_file_perms; # Read from /dev/hw_random if present. # system/core/init/init.c - mix_hwrng_into_linux_rng_action allow init hw_random_device:chr_file r_file_perms; # Create and access /dev files without a specific type, # e.g. /dev/.coldboot_done, /dev/.booting # TODO: Move these files into their own type unless they are # only ever accessed by init. allow init device:file create_file_perms; # keychord configuration allow init self:capability sys_tty_config; allow init keychord_device:chr_file rw_file_perms; # Access device mapper for setting up dm-verity allow init dm_device:chr_file rw_file_perms; allow init dm_device:blk_file rw_file_perms; # Access metadata block device for storing dm-verity state allow init metadata_block_device:blk_file rw_file_perms; # Read /sys/fs/pstore/console-ramoops to detect restarts caused # by dm-verity detecting corrupted blocks allow init pstorefs:dir search; allow init pstorefs:file r_file_perms; allow init kernel:system syslog_read; # linux keyring configuration allow init init:key { write search setattr }; # Allow init to create /data/unencrypted allow init unencrypted_data_file:dir create_dir_perms; # Allow init to write to /proc/sys/vm/overcommit_memory allow init proc_overcommit_memory:file { write }; unix_socket_connect(init, vold, vold) # Raw writes to misc block device allow init misc_block_device:blk_file w_file_perms; r_dir_file(init, system_file) r_dir_file(init, vendor_file_type) allow init proc_meminfo:file r_file_perms; allow init system_data_file:file { getattr read }; allow init system_data_file:lnk_file r_file_perms; ### ### neverallow rules ### # The init domain is only entered via an exec based transition from the # kernel domain, never via setcon(). neverallow domain init:process dyntransition; neverallow { domain -kernel } init:process transition; neverallow init { file_type fs_type -init_exec }:file entrypoint; # Never read/follow symlinks created by shell or untrusted apps. neverallow init shell_data_file:lnk_file read; neverallow init app_data_file:lnk_file read; # init should never execute a program without changing to another domain. neverallow init { file_type fs_type }:file execute_no_trans; # Init never adds or uses services via service_manager. neverallow init service_manager_type:service_manager { add find }; neverallow init servicemanager:service_manager list; # Init should not be creating subdirectories in /data/local/tmp neverallow init shell_data_file:dir { write add_name remove_name };