typeattribute logd coredomain; init_daemon_domain(logd) # Access device logging gating property get_prop(logd, device_logging_prop) # logd is not allowed to write anywhere other than /data/misc/logd, and then # only on userdebug or eng builds neverallow logd { file_type -runtime_event_log_tags_file # shell_data_file access is needed to dump bugreports -shell_data_file userdebug_or_eng(`-coredump_file -misc_logd_file') with_native_coverage(`-method_trace_data_file') }:file { create write append }; # protect the event-log-tags file neverallow { domain -appdomain # covered below -bootstat -dumpstate -init -logd userdebug_or_eng(`-logpersist') -servicemanager -system_server -surfaceflinger -zygote } runtime_event_log_tags_file:file no_rw_file_perms; neverallow { appdomain -bluetooth -platform_app -priv_app -radio -shell userdebug_or_eng(`-su') -system_app } runtime_event_log_tags_file:file no_rw_file_perms; # Only binder communication between logd and system_server is allowed binder_use(logd) binder_service(logd) binder_call(logd, system_server) add_service(logd, logd_service) allow logd logcat_service:service_manager find; # Read access to pseudo filesystems. r_dir_file(logd, cgroup) r_dir_file(logd, cgroup_v2) r_dir_file(logd, proc_kmsg) r_dir_file(logd, proc_meminfo) allow logd self:global_capability_class_set { setuid setgid setpcap sys_nice audit_control }; allow logd self:global_capability2_class_set syslog; allow logd self:netlink_audit_socket { create_socket_perms_no_ioctl nlmsg_write }; allow logd kernel:system syslog_read; allow logd kmsg_device:chr_file { getattr w_file_perms }; allow logd system_data_file:{ file lnk_file } r_file_perms; allow logd packages_list_file:file r_file_perms; allow logd pstorefs:dir search; allow logd pstorefs:file r_file_perms; userdebug_or_eng(` # Access to /data/misc/logd/event-log-tags allow logd misc_logd_file:dir r_dir_perms; allow logd misc_logd_file:file rw_file_perms; ') allow logd runtime_event_log_tags_file:file rw_file_perms; r_dir_file(logd, domain) allow logd kernel:system syslog_mod; control_logd(logd) read_runtime_log_tags(logd) allow runtime_event_log_tags_file tmpfs:filesystem associate; # Typically harmlessly blindly trying to access via liblog # event tag mapping while in the untrusted_app domain. # Access for that domain is controlled and gated via the # event log tag service (albeit at a performance penalty, # expected to be locally cached). dontaudit domain runtime_event_log_tags_file:file { map open read }; # Logd sets defaults if certain properties are empty. set_prop(logd, logd_prop) ### ### Neverallow rules ### ### logd should NEVER do any of this # Block device access. neverallow logd dev_type:blk_file { read write }; # ptrace any other app neverallow logd domain:process ptrace; # ... and nobody may ptrace me (except on userdebug or eng builds) neverallow { domain userdebug_or_eng(`-crash_dump -llkd') } logd:process ptrace; # Write to /system. neverallow logd system_file_type:dir_file_class_set write; # Write to files in /data/data or system files on /data neverallow logd { app_data_file_type system_data_file packages_list_file -shell_data_file # for bugreports }:dir_file_class_set write; # Only init is allowed to enter the logd domain via exec() neverallow { domain -init } logd:process transition; neverallow * logd:process dyntransition; # protect the event-log-tags file neverallow { domain -init -logd } runtime_event_log_tags_file:file no_w_file_perms;