typeattribute app_zygote coredomain; ###### ###### Policy below is different from regular zygote-spawned apps ###### # The app_zygote needs to be able to transition domains. typeattribute app_zygote mlstrustedsubject; # Allow access to temporary files, which is normally permitted through # a domain macro. tmpfs_domain(app_zygote); # Set the UID/GID of the process. # This will be further limited to a range of isolated UIDs with seccomp. allow app_zygote self:global_capability_class_set { setgid setuid }; # Drop capabilities from bounding set. allow app_zygote self:global_capability_class_set setpcap; # Switch SELinux context to isolated app domain. allow app_zygote self:process setcurrent; allow app_zygote isolated_app:process dyntransition; # For JIT allow app_zygote self:process execmem; # Allow app_zygote to stat the files that it opens. It must # be able to inspect them so that it can reopen them on fork # if necessary: b/30963384. allow app_zygote debugfs_trace_marker:file getattr; # get system_server process group allow app_zygote system_server:process getpgid; # Interaction between the app_zygote and its children. allow app_zygote isolated_app:process setpgid; # TODO (b/63631799) fix this access dontaudit app_zygote mnt_expand_file:dir getattr; # Get seapp_contexts allow app_zygote seapp_contexts_file:file r_file_perms; # Check validity of SELinux context before use. selinux_check_context(app_zygote) # Check SELinux permissions. selinux_check_access(app_zygote) ###### ###### Policy below is shared with regular zygote-spawned apps ###### # Child of zygote. allow app_zygote zygote:fd use; allow app_zygote zygote:process sigchld; # For ART (read /data/dalvik-cache). r_dir_file(app_zygote, dalvikcache_data_file); allow app_zygote dalvikcache_data_file:file execute; # Allow reading/executing installed binaries to enable preloading # application data allow app_zygote apk_data_file:dir r_dir_perms; allow app_zygote apk_data_file:file { r_file_perms execute }; # Allow app_zygote access to /vendor/overlay r_dir_file(app_zygote, vendor_overlay_file) allow app_zygote system_data_file:lnk_file r_file_perms; allow app_zygote system_data_file:file { getattr read map }; ##### ##### Neverallow ##### # Only permit transition to isolated_app. neverallow app_zygote { domain -isolated_app }:process dyntransition; # Only setcon() transitions, no exec() based transitions, except for crash_dump. neverallow app_zygote { domain -crash_dump }:process transition; # Must not exec() a program without changing domains. # Having said that, exec() above is not allowed. neverallow app_zygote *:file execute_no_trans; # The only way to enter this domain is for the zygote to fork a new # app_zygote child. neverallow { domain -zygote } app_zygote:process dyntransition; # Disallow write access to properties. neverallow app_zygote property_socket:sock_file write; neverallow app_zygote property_type:property_service set; # Should not have any access to non-app data files. neverallow app_zygote { bluetooth_data_file nfc_data_file radio_data_file shell_data_file }:file { rwx_file_perms }; neverallow app_zygote { service_manager_type -activity_service -ashmem_device_service -webviewupdate_service }:service_manager find; # Isolated apps should not be able to access the driver directly. neverallow app_zygote gpu_device:chr_file { rwx_file_perms }; # Do not allow app_zygote access to /cache. neverallow app_zygote cache_file:dir ~{ r_dir_perms }; neverallow app_zygote cache_file:file ~{ read getattr }; # Do not allow most socket access. This is socket_class_set, excluding unix_dgram_socket, # unix_stream_socket, and netlink_selinux_socket. neverallow app_zygote domain:{ socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket appletalk_socket netlink_route_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_audit_socket netlink_dnrt_socket netlink_kobject_uevent_socket tun_socket netlink_iscsi_socket netlink_fib_lookup_socket netlink_connector_socket netlink_netfilter_socket netlink_generic_socket netlink_scsitransport_socket netlink_rdma_socket netlink_crypto_socket sctp_socket icmp_socket ax25_socket ipx_socket netrom_socket atmpvc_socket x25_socket rose_socket decnet_socket atmsvc_socket rds_socket irda_socket pppox_socket llc_socket can_socket tipc_socket bluetooth_socket iucv_socket rxrpc_socket isdn_socket phonet_socket ieee802154_socket caif_socket alg_socket nfc_socket vsock_socket kcm_socket qipcrtr_socket smc_socket } *; # Only allow app_zygote to talk to the logd socket, and su/heapprofd on eng/userdebug # This is because cap_setuid/cap_setgid allow to forge uid/gid in SCM_CREDENTIALS. # Think twice before changing. neverallow app_zygote { domain -app_zygote -logd userdebug_or_eng(`-su') userdebug_or_eng(`-heapprofd') }:unix_dgram_socket *; neverallow app_zygote { domain -app_zygote userdebug_or_eng(`-su') userdebug_or_eng(`-heapprofd') }:unix_stream_socket *; # Never allow ptrace neverallow app_zygote *:process ptrace; # Do not allow access to Bluetooth-related system properties. # neverallow rules for Bluetooth-related data files are listed above. neverallow app_zygote { bluetooth_a2dp_offload_prop bluetooth_audio_hal_prop bluetooth_prop exported_bluetooth_prop }:file create_file_perms;