# # System Server aka system_server spawned by zygote. # Most of the framework services run in this process. # type system_server, domain, domain_deprecated, mlstrustedsubject; # Define a type for tmpfs-backed ashmem regions. tmpfs_domain(system_server) # For art. allow system_server dalvikcache_data_file:file execute; allow system_server dalvikcache_data_file:dir r_dir_perms; # Enable system server to check the foreign dex usage markers. # We need search on top level directories so that we can get to the files allow system_server user_profile_data_file:dir search; allow system_server user_profile_data_file:file getattr; allow system_server user_profile_foreign_dex_data_file:dir { add_name open read write search remove_name }; allow system_server user_profile_foreign_dex_data_file:file { getattr rename unlink }; # /data/resource-cache allow system_server resourcecache_data_file:file r_file_perms; allow system_server resourcecache_data_file:dir r_dir_perms; # ptrace to processes in the same domain for debugging crashes. allow system_server self:process ptrace; # Child of the zygote. allow system_server zygote:fd use; allow system_server zygote:process sigchld; allow system_server zygote_tmpfs:file read; # May kill zygote on crashes. allow system_server zygote:process sigkill; # Read /system/bin/app_process. allow system_server zygote_exec:file r_file_perms; # Needed to close the zygote socket, which involves getopt / getattr allow system_server zygote:unix_stream_socket { getopt getattr }; # system server gets network and bluetooth permissions. net_domain(system_server) bluetooth_domain(system_server) # These are the capabilities assigned by the zygote to the # system server. allow system_server self:capability { ipc_lock kill net_admin net_bind_service net_broadcast net_raw sys_boot sys_nice sys_resource sys_time sys_tty_config }; wakelock_use(system_server) # Triggered by /proc/pid accesses, not allowed. dontaudit system_server self:capability sys_ptrace; # Trigger module auto-load. allow system_server kernel:system module_request; # Use netlink uevent sockets. allow system_server self:netlink_kobject_uevent_socket create_socket_perms; # Use generic netlink sockets. allow system_server self:netlink_socket create_socket_perms; allow system_server self:netlink_generic_socket create_socket_perms; # Use generic "sockets" where the address family is not known # to the kernel. allow system_server self:socket create_socket_perms; # Set and get routes directly via netlink. allow system_server self:netlink_route_socket nlmsg_write; # Kill apps. allow system_server { appdomain autoplay_app }:process { sigkill signal }; # Set scheduling info for apps. allow system_server { appdomain autoplay_app }:process { getsched setsched }; allow system_server audioserver:process { getsched setsched }; allow system_server cameraserver:process { getsched setsched }; allow system_server mediaserver:process { getsched setsched }; allow system_server bootanim:process { getsched setsched }; # Read /proc/pid data for all domains. This is used by ProcessCpuTracker # within system_server to keep track of memory and CPU usage for # all processes on the device. In addition, /proc/pid files access is needed # for dumping stack traces of native processes. r_dir_file(system_server, domain) # Read/Write to /proc/net/xt_qtaguid/ctrl and and /dev/xt_qtaguid. allow system_server qtaguid_proc:file rw_file_perms; allow system_server qtaguid_device:chr_file rw_file_perms; # Read /proc/uid_cputime/show_uid_stat. allow system_server proc_uid_cputime_showstat:file r_file_perms; # Write /proc/uid_cputime/remove_uid_range. allow system_server proc_uid_cputime_removeuid:file { w_file_perms getattr }; # Write to /proc/sysrq-trigger. allow system_server proc_sysrq:file rw_file_perms; # Read /sys/kernel/debug/wakeup_sources. allow system_server debugfs:file r_file_perms; # The DhcpClient and WifiWatchdog use packet_sockets allow system_server self:packet_socket create_socket_perms; # NetworkDiagnostics requires explicit bind() calls to ping sockets. These aren't actually the same # as raw sockets, but the kernel doesn't yet distinguish between the two. allow system_server node:rawip_socket node_bind; # 3rd party VPN clients require a tun_socket to be created allow system_server self:tun_socket create_socket_perms; # Notify init of death. allow system_server init:process sigchld; # Talk to init and various daemons via sockets. unix_socket_connect(system_server, installd, installd) unix_socket_connect(system_server, lmkd, lmkd) unix_socket_connect(system_server, mtpd, mtp) unix_socket_connect(system_server, netd, netd) unix_socket_connect(system_server, vold, vold) unix_socket_connect(system_server, zygote, zygote) unix_socket_connect(system_server, gps, gpsd) unix_socket_connect(system_server, racoon, racoon) unix_socket_send(system_server, wpa, wpa) unix_socket_connect(system_server, uncrypt, uncrypt) # Communicate over a socket created by surfaceflinger. allow system_server surfaceflinger:unix_stream_socket { read write setopt }; # Perform Binder IPC. binder_use(system_server) binder_call(system_server, binderservicedomain) binder_call(system_server, gatekeeperd) binder_call(system_server, fingerprintd) binder_call(system_server, { appdomain autoplay_app }) binder_call(system_server, dumpstate) binder_call(system_server, netd) binder_service(system_server) # Ask debuggerd to dump backtraces for native stacks of interest. # # This is derived from the list that system server defines as interesting native processes # to dump during ANRs or watchdog aborts, defined in NATIVE_STACKS_OF_INTEREST in # frameworks/base/services/core/java/com/android/server/Watchdog.java. allow system_server { audioserver bluetooth cameraserver drmserver inputflinger mediacodec mediadrmserver mediaextractor mediaserver sdcardd surfaceflinger }:debuggerd dump_backtrace; # Use sockets received over binder from various services. allow system_server audioserver:tcp_socket rw_socket_perms; allow system_server audioserver:udp_socket rw_socket_perms; allow system_server mediaserver:tcp_socket rw_socket_perms; allow system_server mediaserver:udp_socket rw_socket_perms; # Use sockets received over binder from various services. allow system_server mediadrmserver:tcp_socket rw_socket_perms; allow system_server mediadrmserver:udp_socket rw_socket_perms; # Check SELinux permissions. selinux_check_access(system_server) # XXX Label sysfs files with a specific type? allow system_server sysfs:file rw_file_perms; allow system_server sysfs_nfc_power_writable:file rw_file_perms; allow system_server sysfs_devices_system_cpu:file w_file_perms; allow system_server sysfs_mac_address:file r_file_perms; allow system_server sysfs_thermal:dir search; allow system_server sysfs_thermal:file r_file_perms; # TODO: added to match above sysfs rule. Remove me? allow system_server sysfs_usb:file w_file_perms; # Access devices. allow system_server device:dir r_dir_perms; allow system_server mdns_socket:sock_file rw_file_perms; allow system_server alarm_device:chr_file rw_file_perms; allow system_server gpu_device:chr_file rw_file_perms; allow system_server iio_device:chr_file rw_file_perms; allow system_server input_device:dir r_dir_perms; allow system_server input_device:chr_file rw_file_perms; allow system_server radio_device:chr_file r_file_perms; allow system_server tty_device:chr_file rw_file_perms; allow system_server usbaccessory_device:chr_file rw_file_perms; allow system_server video_device:dir r_dir_perms; allow system_server video_device:chr_file rw_file_perms; allow system_server adbd_socket:sock_file rw_file_perms; allow system_server rtc_device:chr_file rw_file_perms; allow system_server audio_device:dir r_dir_perms; # write access needed for MIDI allow system_server audio_device:chr_file rw_file_perms; # tun device used for 3rd party vpn apps allow system_server tun_device:chr_file rw_file_perms; # Manage system data files. allow system_server system_data_file:dir create_dir_perms; allow system_server system_data_file:notdevfile_class_set create_file_perms; allow system_server keychain_data_file:dir create_dir_perms; allow system_server keychain_data_file:file create_file_perms; # Manage /data/app. allow system_server apk_data_file:dir create_dir_perms; allow system_server apk_data_file:file { create_file_perms link }; allow system_server apk_tmp_file:dir create_dir_perms; allow system_server apk_tmp_file:file create_file_perms; # Manage /data/app-private. allow system_server apk_private_data_file:dir create_dir_perms; allow system_server apk_private_data_file:file create_file_perms; allow system_server apk_private_tmp_file:dir create_dir_perms; allow system_server apk_private_tmp_file:file create_file_perms; # Manage files within asec containers. allow system_server asec_apk_file:dir create_dir_perms; allow system_server asec_apk_file:file create_file_perms; allow system_server asec_public_file:file create_file_perms; # Manage /data/anr. allow system_server anr_data_file:dir create_dir_perms; allow system_server anr_data_file:file create_file_perms; # Manage /data/backup. allow system_server backup_data_file:dir create_dir_perms; allow system_server backup_data_file:file create_file_perms; # Write to /data/system/heapdump allow system_server heapdump_data_file:dir rw_dir_perms; allow system_server heapdump_data_file:file create_file_perms; # Manage /data/misc/adb. allow system_server adb_keys_file:dir create_dir_perms; allow system_server adb_keys_file:file create_file_perms; # Manage /data/misc/sms. # TODO: Split into a separate type? allow system_server radio_data_file:dir create_dir_perms; allow system_server radio_data_file:file create_file_perms; # Manage /data/misc/systemkeys. allow system_server systemkeys_data_file:dir create_dir_perms; allow system_server systemkeys_data_file:file create_file_perms; # Access /data/tombstones. allow system_server tombstone_data_file:dir r_dir_perms; allow system_server tombstone_data_file:file r_file_perms; # Manage /data/misc/vpn. allow system_server vpn_data_file:dir create_dir_perms; allow system_server vpn_data_file:file create_file_perms; # Manage /data/misc/wifi. allow system_server wifi_data_file:dir create_dir_perms; allow system_server wifi_data_file:file create_file_perms; # Manage /data/misc/zoneinfo. allow system_server zoneinfo_data_file:dir create_dir_perms; allow system_server zoneinfo_data_file:file create_file_perms; # Walk /data/data subdirectories. # Types extracted from seapp_contexts type= fields. allow system_server { system_app_data_file bluetooth_data_file nfc_data_file radio_data_file shell_data_file app_data_file autoplay_data_file }:dir { getattr read search }; # Also permit for unlabeled /data/data subdirectories and # for unlabeled asec containers on upgrades from 4.2. allow system_server unlabeled:dir r_dir_perms; # Read pkg.apk file before it has been relabeled by vold. allow system_server unlabeled:file r_file_perms; # Populate com.android.providers.settings/databases/settings.db. allow system_server system_app_data_file:dir create_dir_perms; allow system_server system_app_data_file:file create_file_perms; # Receive and use open app data files passed over binder IPC. # Types extracted from seapp_contexts type= fields. allow system_server { system_app_data_file bluetooth_data_file nfc_data_file radio_data_file shell_data_file app_data_file }:file { getattr read write }; # Receive and use open /data/media files passed over binder IPC. allow system_server media_rw_data_file:file { getattr read write }; # Read /file_contexts and /data/security/file_contexts security_access_policy(system_server) # Relabel apk files. allow system_server { apk_tmp_file apk_private_tmp_file }:{ dir file } { relabelfrom relabelto }; allow system_server { apk_data_file apk_private_data_file }:{ dir file } { relabelfrom relabelto }; # Relabel wallpaper. allow system_server system_data_file:file relabelfrom; allow system_server wallpaper_file:file relabelto; allow system_server wallpaper_file:file { rw_file_perms rename unlink }; # Backup of wallpaper imagery uses temporary hard links to avoid data churn allow system_server { system_data_file wallpaper_file }:file link; # ShortcutManager icons allow system_server system_data_file:dir relabelfrom; allow system_server shortcut_manager_icons:dir { create_dir_perms relabelto }; allow system_server shortcut_manager_icons:file create_file_perms; # Manage ringtones. allow system_server ringtone_file:dir { create_dir_perms relabelto }; allow system_server ringtone_file:file create_file_perms; # Relabel icon file. allow system_server icon_file:file relabelto; allow system_server icon_file:file { rw_file_perms unlink }; # FingerprintService.java does a restorecon of the directory /data/system/users/[0-9]+/fpdata(/.*)? allow system_server system_data_file:dir relabelfrom; # Property Service write set_prop(system_server, system_prop) set_prop(system_server, safemode_prop) set_prop(system_server, dhcp_prop) set_prop(system_server, net_radio_prop) set_prop(system_server, system_radio_prop) set_prop(system_server, debug_prop) set_prop(system_server, powerctl_prop) set_prop(system_server, fingerprint_prop) set_prop(system_server, device_logging_prop) userdebug_or_eng(`set_prop(system_server, wifi_log_prop)') # ctl interface set_prop(system_server, ctl_default_prop) set_prop(system_server, ctl_bugreport_prop) # cppreopt property set_prop(system_server, cppreopt_prop) # Create a socket for receiving info from wpa. type_transition system_server wifi_data_file:sock_file system_wpa_socket; type_transition system_server wpa_socket:sock_file system_wpa_socket; allow system_server wpa_socket:dir rw_dir_perms; allow system_server system_wpa_socket:sock_file create_file_perms; # Remove sockets created by wpa_supplicant allow system_server wpa_socket:sock_file unlink; # Create a socket for connections from debuggerd. type_transition system_server system_data_file:sock_file system_ndebug_socket "ndebugsocket"; allow system_server system_ndebug_socket:sock_file create_file_perms; # Manage cache files. allow system_server { cache_file cache_recovery_file }:dir { relabelfrom create_dir_perms }; allow system_server { cache_file cache_recovery_file }:file { relabelfrom create_file_perms }; allow system_server { cache_file cache_recovery_file }:fifo_file create_file_perms; # Run system programs, e.g. dexopt. allow system_server system_file:file x_file_perms; # LocationManager(e.g, GPS) needs to read and write # to uart driver and ctrl proc entry allow system_server gps_device:chr_file rw_file_perms; allow system_server gps_control:file rw_file_perms; # Allow system_server to use app-created sockets and pipes. allow system_server { appdomain autoplay_app }:{ tcp_socket udp_socket } { getattr getopt setopt read write shutdown }; allow system_server { appdomain autoplay_app }:{ fifo_file unix_stream_socket } { getattr read write }; # Allow abstract socket connection allow system_server rild:unix_stream_socket connectto; # BackupManagerService needs to manipulate backup data files allow system_server cache_backup_file:dir rw_dir_perms; allow system_server cache_backup_file:file create_file_perms; # LocalTransport works inside /cache/backup allow system_server cache_private_backup_file:dir create_dir_perms; allow system_server cache_private_backup_file:file create_file_perms; # Allow system to talk to usb device allow system_server usb_device:chr_file rw_file_perms; allow system_server usb_device:dir r_dir_perms; # Allow system to talk to sensors allow system_server sensors_device:chr_file rw_file_perms; # Read from HW RNG (needed by EntropyMixer). allow system_server hw_random_device:chr_file r_file_perms; # Read and delete files under /dev/fscklogs. r_dir_file(system_server, fscklogs) allow system_server fscklogs:dir { write remove_name }; allow system_server fscklogs:file unlink; # logd access, system_server inherit logd write socket # (urge is to deprecate this long term) allow system_server zygote:unix_dgram_socket write; # Read from log daemon. read_logd(system_server) # Be consistent with DAC permissions. Allow system_server to write to # /sys/module/lowmemorykiller/parameters/adj # /sys/module/lowmemorykiller/parameters/minfree allow system_server sysfs_lowmemorykiller:file { getattr w_file_perms }; # Read /sys/fs/pstore/console-ramoops # Don't worry about overly broad permissions for now, as there's # only one file in /sys/fs/pstore allow system_server pstorefs:dir r_dir_perms; allow system_server pstorefs:file r_file_perms; # /sys access allow system_server sysfs_zram:dir search; allow system_server sysfs_zram:file r_file_perms; allow system_server audioserver_service:service_manager find; allow system_server cameraserver_service:service_manager find; allow system_server drmserver_service:service_manager find; allow system_server batteryproperties_service:service_manager find; allow system_server keystore_service:service_manager find; allow system_server gatekeeper_service:service_manager find; allow system_server fingerprintd_service:service_manager find; allow system_server mediaserver_service:service_manager find; allow system_server mediaextractor_service:service_manager find; allow system_server mediacodec_service:service_manager find; allow system_server mediadrmserver_service:service_manager find; allow system_server netd_service:service_manager find; allow system_server nfc_service:service_manager find; allow system_server radio_service:service_manager find; allow system_server system_server_service:service_manager { add find }; allow system_server surfaceflinger_service:service_manager find; allow system_server keystore:keystore_key { get_state get insert delete exist list reset password lock unlock is_empty sign verify grant duplicate clear_uid add_auth user_changed }; # Allow system server to search and write to the persistent factory reset # protection partition. This block device does not get wiped in a factory reset. allow system_server block_device:dir search; allow system_server frp_block_device:blk_file rw_file_perms; # Clean up old cgroups allow system_server cgroup:dir { remove_name rmdir }; # /oem access r_dir_file(system_server, oemfs) # Allow resolving per-user storage symlinks allow system_server { mnt_user_file storage_file }:dir { getattr search }; allow system_server { mnt_user_file storage_file }:lnk_file { getattr read }; # Allow statfs() on storage devices, which happens fast enough that # we shouldn't be killed during unsafe removal allow system_server sdcard_type:dir { getattr search }; # Traverse into expanded storage allow system_server mnt_expand_file:dir r_dir_perms; # Allow system process to relabel the fingerprint directory after mkdir # and delete the directory and files when no longer needed allow system_server fingerprintd_data_file:dir { r_dir_perms remove_name rmdir relabelto write }; allow system_server fingerprintd_data_file:file { getattr unlink }; # Allow system process to read network MAC address allow system_server sysfs_mac_address:file r_file_perms; userdebug_or_eng(` # Allow system server to create and write method traces in /data/misc/trace. allow system_server method_trace_data_file:dir w_dir_perms; allow system_server method_trace_data_file:file { create w_file_perms }; # Allow system server to read dmesg allow system_server kernel:system syslog_read; ') # For AppFuse. allow system_server vold:fd use; allow system_server fuse_device:chr_file { read write ioctl getattr }; # For configuring sdcardfs allow system_server configfs:dir { create_dir_perms }; allow system_server configfs:file { getattr open unlink write }; # Connect to adbd and use a socket transferred from it. # Used for e.g. jdwp. allow system_server adbd:unix_stream_socket connectto; allow system_server adbd:fd use; allow system_server adbd:unix_stream_socket { getattr getopt ioctl read write shutdown }; # Access to /data/media. # This should be removed if sdcardfs is modified to alter the secontext for its # accesses to the underlying FS. allow system_server media_rw_data_file:dir search; # Allow invoking tools like "timeout" allow system_server toolbox_exec:file rx_file_perms; # Postinstall # # For OTA dexopt, allow calls coming from postinstall. binder_call(system_server, postinstall) allow system_server postinstall:fifo_file write; allow system_server update_engine:fd use; allow system_server update_engine:fifo_file write; # Access to /data/preloads allow system_server preloads_data_file:file { r_file_perms unlink }; allow system_server preloads_data_file:dir { r_dir_perms write remove_name rmdir }; ### ### Neverallow rules ### ### system_server should NEVER do any of this # Do not allow opening files from external storage as unsafe ejection # could cause the kernel to kill the system_server. neverallow system_server sdcard_type:dir { open read write }; neverallow system_server sdcard_type:file rw_file_perms; # system server should never be opening zygote spawned app data # files directly. Rather, they should always be passed via a # file descriptor. # Types extracted from seapp_contexts type= fields, excluding # those types that system_server needs to open directly. neverallow system_server { bluetooth_data_file nfc_data_file shell_data_file app_data_file }:file open; # system_server should never be executing dex2oat. This is either # a bug (for example, bug 16317188), or represents an attempt by # system server to dynamically load a dex file, something we do not # want to allow. neverallow system_server dex2oat_exec:file no_x_file_perms; # system_server should never execute anything from /data except for /data/dalvik-cache files. neverallow system_server { data_file_type -dalvikcache_data_file #mapping with PROT_EXEC }:file no_x_file_perms; # The only block device system_server should be accessing is # the frp_block_device. This helps avoid a system_server to root # escalation by writing to raw block devices. neverallow system_server { dev_type -frp_block_device }:blk_file no_rw_file_perms; # system_server should never use JIT functionality neverallow system_server self:process execmem; neverallow system_server ashmem_device:chr_file execute; neverallow system_server system_server_tmpfs:file execute;