blob: c92830f8f5e41d963defbcfe6e755ff03b41efca [file] [log] [blame]
# Rules for all domains.
# Allow reaping by init.
allow domain init:process sigchld;
# Intra-domain accesses.
allow domain self:process {
fork
sigchld
sigkill
sigstop
signull
signal
getsched
setsched
getsession
getpgid
setpgid
getcap
setcap
getattr
setrlimit
};
allow domain self:fd use;
allow domain proc:dir r_dir_perms;
allow domain proc_net_type:dir search;
r_dir_file(domain, self)
allow domain self:{ fifo_file file } rw_file_perms;
allow domain self:unix_dgram_socket { create_socket_perms sendto };
allow domain self:unix_stream_socket { create_stream_socket_perms connectto };
# Inherit or receive open files from others.
allow domain init:fd use;
userdebug_or_eng(`
allow domain su:fd use;
allow domain su:unix_stream_socket { connectto getattr getopt read write shutdown };
allow domain su:unix_dgram_socket sendto;
allow { domain -init } su:binder { call transfer };
# Running something like "pm dump com.android.bluetooth" requires
# fifo writes
allow domain su:fifo_file { write getattr };
# allow "gdbserver --attach" to work for su.
allow domain su:process sigchld;
# Allow writing coredumps to /cores/*
allow domain coredump_file:file create_file_perms;
allow domain coredump_file:dir ra_dir_perms;
')
with_native_coverage(`
# Allow writing coverage information to /data/misc/trace
allow domain method_trace_data_file:dir create_dir_perms;
allow domain method_trace_data_file:file create_file_perms;
')
# Allow everyone to read aconfig flags
get_prop(domain, device_config_aconfig_flags_prop);
# Root fs.
allow domain tmpfs:dir { getattr search };
allow domain rootfs:dir search;
allow domain rootfs:lnk_file { read getattr };
# Device accesses.
allow domain device:dir search;
allow domain dev_type:lnk_file r_file_perms;
allow domain devpts:dir search;
allow domain dmabuf_heap_device:dir r_dir_perms;
allow domain socket_device:dir r_dir_perms;
allow domain owntty_device:chr_file rw_file_perms;
allow domain null_device:chr_file rw_file_perms;
allow domain zero_device:chr_file rw_file_perms;
# /dev/ashmem is being deprecated by means of constraining and eventually
# removing all "open" permissions. We preserve the other permissions.
allow domain ashmem_device:chr_file { getattr read ioctl lock map append write };
# This device is used by libcutils, which is accessible to everyone.
allow domain ashmem_libcutils_device:chr_file rw_file_perms;
# /dev/binder can be accessed by ... everyone! :)
allow { domain -hwservicemanager -vndservicemanager } binder_device:chr_file rw_file_perms;
get_prop({domain -hwservicemanager -vndservicemanager }, servicemanager_prop)
# Restrict binder ioctls to an allowlist. Additional ioctl commands may be
# added to individual domains, but this sets safe defaults for all processes.
allowxperm domain binder_device:chr_file ioctl { unpriv_binder_ioctls };
# /dev/binderfs needs to be accessed by everyone too!
allow domain binderfs:dir { getattr search };
allow domain binderfs_logs_proc:dir search;
allow domain binderfs_features:dir search;
allow domain binderfs_features:file r_file_perms;
allow { domain -servicemanager -vndservicemanager -isolated_app } hwbinder_device:chr_file rw_file_perms;
allow domain ptmx_device:chr_file rw_file_perms;
allow domain random_device:chr_file rw_file_perms;
allow domain proc_random:dir r_dir_perms;
allow domain proc_random:file r_file_perms;
allow domain properties_device:dir { search getattr };
allow domain properties_serial:file r_file_perms;
allow domain property_info:file r_file_perms;
# Let everyone read log properties, so that liblog can avoid sending unloggable
# messages to logd.
get_prop(domain, log_property_type)
dontaudit domain property_type:file audit_access;
allow domain property_contexts_file:file r_file_perms;
allow domain init:key search;
allow domain vold:key search;
# logd access
write_logd(domain)
# Directory/link file access for path resolution.
allow domain {
system_file
system_lib_file
system_seccomp_policy_file
system_security_cacerts_file
}:dir r_dir_perms;
allow domain system_file:lnk_file { getattr read };
# Global access to /system/etc/security/cacerts/*, /system/etc/seccomp_policy/*, /system/lib[64]/*,
# /(system|product|system_ext)/etc/(group|passwd), linker and its config.
allow domain system_seccomp_policy_file:file r_file_perms;
# cacerts are accessible from public Java API.
allow domain system_security_cacerts_file:file r_file_perms;
allow domain system_group_file:file r_file_perms;
allow domain system_passwd_file:file r_file_perms;
allow domain system_linker_exec:file { execute read open getattr map };
allow domain system_linker_config_file:file r_file_perms;
allow domain system_lib_file:file { execute read open getattr map };
# To allow following symlinks at /system/bin/linker, /system/lib/libc.so, etc.
allow domain system_linker_exec:lnk_file { read open getattr };
allow domain system_lib_file:lnk_file { read open getattr };
allow domain system_event_log_tags_file:file r_file_perms;
allow { appdomain coredomain } system_file:file { execute read open getattr map };
# Make sure system/vendor split doesn not affect non-treble
# devices
not_full_treble(`
allow domain system_file:file { execute read open getattr map };
allow domain vendor_file_type:dir { search getattr };
allow domain vendor_file_type:file { execute read open getattr map };
allow domain vendor_file_type:lnk_file { getattr read };
')
# All domains are allowed to open and read directories
# that contain HAL implementations (e.g. passthrough
# HALs require clients to have these permissions)
allow domain vendor_hal_file:dir r_dir_perms;
# Everyone can read and execute all same process HALs
allow domain same_process_hal_file:dir r_dir_perms;
allow {
domain
-coredomain # access is explicitly granted to individual coredomains
} same_process_hal_file:file { execute read open getattr map };
# Any process can load vndk-sp libraries, which are system libraries
# used by same process HALs
allow domain vndk_sp_file:dir r_dir_perms;
allow domain vndk_sp_file:file { execute read open getattr map };
# All domains get access to /vendor/etc
allow domain vendor_configs_file:dir r_dir_perms;
allow domain vendor_configs_file:file { read open getattr map };
full_treble_only(`
# Allow all domains to be able to follow /system/vendor and/or
# /vendor/odm symlinks.
allow domain vendor_file_type:lnk_file { getattr open read };
# This is required to be able to search & read /vendor/lib64
# in order to lookup vendor libraries. The execute permission
# for coredomains is granted *only* for same process HALs
allow domain vendor_file:dir { getattr search };
# Allow reading and executing out of /vendor to all vendor domains
allow { domain -coredomain } vendor_file_type:dir r_dir_perms;
allow { domain -coredomain } vendor_file_type:file { read open getattr execute map };
allow { domain -coredomain } vendor_file_type:lnk_file { getattr read };
')
# read and stat any sysfs symlinks
allow domain sysfs:lnk_file { getattr read };
# libc references /system/usr/share/zoneinfo for timezone related information.
# This directory is considered to be a VNDK-stable
allow domain { system_zoneinfo_file }:file r_file_perms;
allow domain { system_zoneinfo_file }:dir r_dir_perms;
# Lots of processes access current CPU information
r_dir_file(domain, sysfs_devices_system_cpu)
r_dir_file(domain, sysfs_usb);
# If kernel CONFIG_TRANSPARENT_HUGEPAGE is enabled, libjemalloc5 (statically
# included by libc) reads /sys/kernel/mm/transparent_hugepage/enabled.
allow domain sysfs_transparent_hugepage:dir search;
allow domain sysfs_transparent_hugepage:file r_file_perms;
# Allow search access, and sometimes getattr access, to various directories
# under /data. We are fairly lenient in allowing search access to top-level
# dirs that commonly need to be traversed to get access to the "real" files, as
# this greatly simplifies the policy and doesn't open up much attack surface.
not_full_treble(`
allow domain system_data_file:dir getattr;
')
allow { coredomain appdomain } system_data_file:dir getattr;
# Anything that accesses anything in /data needs search access to /data itself.
# This includes vendor components, as they need to access /data/vendor.
allow domain system_data_root_file:dir { search getattr } ;
# system_data_file is the default type for directories in /data. Anything
# accessing data files with a more specific type often has to traverse a
# system_data_file directory such as /data/misc to get there.
allow domain system_data_file:dir search;
# Anything that accesses files in /data/user (and /data/user_de, etc.) needs
# search access to these directories themselves. getattr access is sometimes
# needed too.
allow { coredomain appdomain } system_userdir_file:dir { search getattr };
# Anything that accesses files in /data/media needs search access to /data/media
# itself.
allow { coredomain appdomain } media_userdir_file:dir search;
# TODO restrict this to non-coredomain
allow domain vendor_userdir_file:dir { getattr search };
allow domain vendor_data_file:dir { getattr search };
# required by the dynamic linker
allow domain proc:lnk_file { getattr read };
# /proc/cpuinfo
allow domain proc_cpuinfo:file r_file_perms;
# /dev/cpu_variant:.*
allow domain dev_cpu_variant:file r_file_perms;
# profiling needs to read /proc/sys/kernel/perf_event_max_sample_rate
allow domain proc_perf:file r_file_perms;
# toybox loads libselinux which stats /sys/fs/selinux/
allow domain selinuxfs:dir search;
allow domain selinuxfs:file getattr;
allow domain sysfs:dir search;
allow domain selinuxfs:filesystem getattr;
# Almost all processes log tracing information to
# /sys/kernel/debug/tracing/trace_marker
# The reason behind this is documented in b/6513400
allow domain debugfs:dir search;
allow domain debugfs_tracing:dir search;
allow domain debugfs_tracing_debug:dir search;
allow domain debugfs_trace_marker:file w_file_perms;
# Linux lockdown mode offered coarse-grained definitions for access controls. In
# previous versions of the policy, the integrity permission was neverallowed.
# It was found that this permission mainly duplicates pre-existing rules in
# the policy (see b/285443587). Additionally, some access were found to be
# required (b/269377822). The access vector was removed from kernel 5.16
# onwards. Grant unconditional access, these rules should be removed from the
# policy once no kernel <5.16 are supported.
allow domain self:lockdown { confidentiality integrity };
# Filesystem access.
allow domain fs_type:filesystem getattr;
allow domain fs_type:dir getattr;
# Restrict all domains to an allowlist for common socket types. Additional
# ioctl commands may be added to individual domains, but this sets safe
# defaults for all processes. Note that granting this allowlist to domain does
# not grant the ioctl permission on these socket types. That must be granted
# separately.
allowxperm domain domain:{ icmp_socket rawip_socket tcp_socket udp_socket }
ioctl { unpriv_sock_ioctls unpriv_tty_ioctls };
# default allowlist for unix sockets.
allowxperm domain { domain pdx_channel_socket_type }:{ unix_dgram_socket unix_stream_socket }
ioctl unpriv_unix_sock_ioctls;
# Restrict PTYs to only allowed ioctls.
# Note that granting this allowlist to domain does
# not grant the wider ioctl permission. That must be granted
# separately.
allowxperm domain devpts:chr_file ioctl unpriv_tty_ioctls;
# All domains must clearly enumerate what ioctls they use
# on filesystem objects (plain files, directories, symbolic links,
# named pipes, and named sockets). We start off with a safe set.
allowxperm domain { file_type fs_type domain dev_type }:{ dir notdevfile_class_set blk_file } ioctl { FIOCLEX FIONCLEX };
# If a domain has ioctl access to tun_device, it must clearly enumerate the
# ioctls used. Safe defaults are listed below.
allowxperm domain tun_device:chr_file ioctl { FIOCLEX FIONCLEX };
# Allow a process to make a determination whether a file descriptor
# for a plain file or pipe (fifo_file) is a tty. Note that granting
# this allowlist to domain does not grant the ioctl permission to
# these files. That must be granted separately.
allowxperm domain { file_type fs_type }:file ioctl { TCGETS };
allowxperm domain domain:fifo_file ioctl { TCGETS };
# If a domain has access to perform an ioctl on a block device, allow these
# very common, benign ioctls
allowxperm domain dev_type:blk_file ioctl { BLKGETSIZE64 BLKSSZGET };
# Support sqlite F2FS specific optimizations
# ioctl permission on the specific file type is still required
# TODO: consider only compiling these rules if we know the
# /data partition is F2FS
allowxperm domain { file_type sdcard_type }:file ioctl {
F2FS_IOC_ABORT_VOLATILE_WRITE
F2FS_IOC_COMMIT_ATOMIC_WRITE
F2FS_IOC_GET_FEATURES
F2FS_IOC_GET_PIN_FILE
F2FS_IOC_SET_PIN_FILE
F2FS_IOC_START_ATOMIC_WRITE
};
# Workaround for policy compiler being too aggressive and removing hwservice_manager_type
# when it's not explicitly used in allow rules
allow { domain -domain } hwservice_manager_type:hwservice_manager { add find };
# Workaround for policy compiler being too aggressive and removing vndservice_manager_type
# when it's not explicitly used in allow rules
allow { domain -domain } vndservice_manager_type:service_manager { add find };
# Under ASAN, processes will try to read /data, as the sanitized libraries are there.
with_asan(`allow domain system_data_file:dir getattr;')
# Under ASAN, /system/asan.options needs to be globally accessible.
with_asan(`allow domain system_asan_options_file:file r_file_perms;')
# read APEX dir and stat any symlink pointing to APEXs.
allow domain apex_mnt_dir:dir { getattr search };
allow domain apex_mnt_dir:lnk_file r_file_perms;
# Allow reading /sys/kernel/mm/pgsize_migration/enabled
allow domain sysfs_pgsize_migration:dir search;
allow domain sysfs_pgsize_migration:file r_file_perms;
# Allow everyone to read media server-configurable flags, so that libstagefright can be
# configured using server-configurable flags
get_prop(domain, device_config_media_native_prop)
# Transition to crash_dump when /system/bin/crash_dump* is executed.
# This occurs when the process crashes.
# We do not apply this to the su domain to avoid interfering with
# tests (b/114136122)
domain_auto_trans({ domain userdebug_or_eng(`-su') }, crash_dump_exec, crash_dump);
allow domain crash_dump:process sigchld;
# Allow every process to check the heapprofd.enable properties to determine
# whether to load the heap profiling library. This does not necessarily enable
# heap profiling, as initialization will fail if it does not have the
# necessary SELinux permissions.
get_prop(domain, heapprofd_prop);
# See private/crash_dump.te
define(`dumpable_domain',`{
domain
-apexd
-bpfloader
-crash_dump
-crosvm # TODO(b/236672526): Remove exception for crosvm
-init
-kernel
-keystore
-llkd
-logd
-ueventd
-vendor_init
-vold
}')
# Allow heap profiling by heapprofd.
# Zygotes are excluded due to potential issues with holding open file
# descriptors or other state across forks. Other exclusions conflict with
# neverallows, and are not considered important to profile.
can_profile_heap({
dumpable_domain
-app_zygote
-hal_configstore_server
-logpersist
-recovery
-recovery_persist
-recovery_refresh
-webview_zygote
-zygote
})
# Allow profiling using perf_event_open by traced_perf.
can_profile_perf({
dumpable_domain
-app_zygote
-hal_configstore_server
-webview_zygote
-zygote
})
# Everyone can access the IncFS list of features.
r_dir_file(domain, sysfs_fs_incfs_features);
# Everyone can access the fuse list of features.
r_dir_file(domain, sysfs_fs_fuse_features);
# Path resolution access in cgroups.
allow domain cgroup:dir search;
allow { domain -appdomain -rs } cgroup:dir w_dir_perms;
allow { domain -appdomain -rs } cgroup:file w_file_perms;
allow domain cgroup_v2:dir search;
allow { domain -appdomain -rs } cgroup_v2:dir w_dir_perms;
allow { domain -appdomain -rs } cgroup_v2:file w_file_perms;
allow domain cgroup_rc_file:dir search;
allow domain cgroup_rc_file:file r_file_perms;
allow domain task_profiles_file:file r_file_perms;
allow domain task_profiles_api_file:file r_file_perms;
allow domain vendor_task_profiles_file:file r_file_perms;
# Allow all domains to read sys.use_memfd to determine
# if memfd support can be used if device supports it
get_prop(domain, use_memfd_prop);
# Read access to sdkextensions props
get_prop(domain, module_sdkextensions_prop)
# Read access to bq configuration values
get_prop(domain, bq_config_prop);
# Allow all domains to check whether MTE is set to permissive mode.
get_prop(domain, permissive_mte_prop);
# Allow ART to be configurable via device_config properties
# (ART "runs" inside the app process), and MTE bootloader override to be
# observed by everything
get_prop(domain, device_config_memory_safety_native_boot_prop);
get_prop(domain, device_config_memory_safety_native_prop);
get_prop(domain, device_config_runtime_native_boot_prop);
get_prop(domain, device_config_runtime_native_prop);
# For now, everyone can access core property files
# Device specific properties are not granted by default
not_compatible_property(`
# DO NOT ADD ANY PROPERTIES HERE
get_prop(domain, core_property_type)
get_prop(domain, exported3_system_prop)
get_prop(domain, vendor_default_prop)
')
compatible_property_only(`
# DO NOT ADD ANY PROPERTIES HERE
get_prop({coredomain appdomain shell}, core_property_type)
get_prop({coredomain appdomain shell}, exported3_system_prop)
get_prop({coredomain appdomain shell}, exported_camera_prop)
get_prop({coredomain shell}, userspace_reboot_exported_prop)
get_prop({coredomain shell}, userspace_reboot_log_prop)
get_prop({coredomain shell}, userspace_reboot_test_prop)
get_prop({domain -coredomain -appdomain}, vendor_default_prop)
')
# Public readable properties
get_prop(domain, aaudio_config_prop)
get_prop(domain, apexd_select_prop)
get_prop(domain, arm64_memtag_prop)
get_prop(domain, bluetooth_config_prop)
get_prop(domain, bootloader_prop)
get_prop(domain, build_odm_prop)
get_prop(domain, build_prop)
get_prop(domain, build_vendor_prop)
get_prop(domain, debug_prop)
get_prop(domain, exported_config_prop)
get_prop(domain, exported_default_prop)
get_prop(domain, exported_dumpstate_prop)
get_prop(domain, exported_secure_prop)
get_prop(domain, exported_system_prop)
get_prop(domain, fingerprint_prop)
get_prop(domain, framework_status_prop)
get_prop(domain, gwp_asan_prop)
get_prop(domain, hal_instrumentation_prop)
get_prop(domain, hw_timeout_multiplier_prop)
get_prop(domain, init_service_status_prop)
get_prop(domain, libc_debug_prop)
get_prop(domain, locale_prop)
get_prop(domain, logd_prop)
get_prop(domain, mediadrm_config_prop)
get_prop(domain, property_service_version_prop)
get_prop(domain, soc_prop)
get_prop(domain, socket_hook_prop)
get_prop(domain, surfaceflinger_prop)
get_prop(domain, telephony_status_prop)
get_prop(domain, timezone_prop)
get_prop({domain -untrusted_app_all -isolated_app_all -ephemeral_app }, userdebug_or_eng_prop)
get_prop(domain, vendor_socket_hook_prop)
get_prop(domain, vndk_prop)
get_prop(domain, vold_status_prop)
get_prop(domain, vts_config_prop)
# Binder cache properties are world-readable
get_prop(domain, binder_cache_bluetooth_server_prop)
get_prop(domain, binder_cache_system_server_prop)
get_prop(domain, binder_cache_telephony_server_prop)
# Binderfs logs contain sensitive information about other processes.
neverallow {
domain
-init
-vendor_init
userdebug_or_eng(`-dumpstate')
userdebug_or_eng(`-system_server')
} binderfs_logs_transactions:file no_rw_file_perms;
# Binderfs transaction history is less sensitive than transactions, but it
# still contains global information about the system.
neverallow { domain -dumpstate -init -vendor_init -system_server } binderfs_logs_transaction_history:file no_rw_file_perms;
# Allow access to fsverity keyring.
allow domain kernel:key search;
# Allow access to keys in the fsverity keyring that were installed at boot.
allow domain fsverity_init:key search;
# For testing purposes, allow access to keys installed with su.
userdebug_or_eng(`
allow domain su:key search;
')
# Allow access to linkerconfig file
allow domain linkerconfig_file:dir search;
allow domain linkerconfig_file:file r_file_perms;
# Allow all processes to check for the existence of the boringssl_self_test_marker files.
allow domain boringssl_self_test_marker:dir search;
# Allow all processes to read the file_logger property that liblog uses to check if file_logger
# should be used.
get_prop(domain, log_file_logger_prop)
# Allow all processes to connect to PRNG seeder daemon.
unix_socket_connect(domain, prng_seeder, prng_seeder)
# Allow calls to system(3), popen(3), ...
allow {
domain
# Except domains that explicitly neverallow it.
-kernel
-init
-vendor_init
-app_zygote
-webview_zygote
-system_server
-artd
-dexopt_chroot_setup
-audioserver
-cameraserver
-mediadrmserver
-mediaextractor
-mediametrics
-mediaserver
-mediatuner
-mediatranscoding
-ueventd
-hal_audio_server
-hal_camera_server
-hal_cas_server
-hal_codec2_server
-hal_configstore_server
-hal_drm_server
-hal_omx_server
} {shell_exec toolbox_exec}:file rx_file_perms;
# Allow all to read from flag value boot snapshot storage files and general pb files
# The boot snapshot of storage files serves flag read traffic for all processes, thus
# needs to be readable by everybody.
r_dir_file(domain, aconfig_storage_metadata_file);
r_dir_file({ coredomain appdomain }, system_aconfig_storage_file);
r_dir_file({ coredomain appdomain }, aconfig_test_mission_files);
# processes needs to access storage file stored at /metadata/aconfig/boot, require search
# permission on /metadata dir
allow domain metadata_file:dir search;
###
### neverallow rules
###
# All ioctls on file-like objects (except chr_file and blk_file) and
# sockets must be restricted to an allowlist.
neverallowxperm * *:{ dir notdevfile_class_set socket_class_set blk_file } ioctl { 0 };
# b/68014825 and https://android-review.googlesource.com/516535
# rfc6093 says that processes should not use the TCP urgent mechanism
neverallowxperm domain domain:socket_class_set ioctl { SIOCATMARK };
# TIOCSTI is only ever used for exploits. Block it.
# b/33073072, b/7530569
# http://www.openwall.com/lists/oss-security/2016/09/26/14
neverallowxperm * devpts:chr_file ioctl TIOCSTI;
# Do not allow any domain other than init to create unlabeled files.
neverallow { domain -init -recovery } unlabeled:dir_file_class_set create;
# Limit device node creation to these allowed domains.
neverallow {
domain
-kernel
-init
-ueventd
-vold
} self:global_capability_class_set mknod;
# No process can map low memory (< CONFIG_LSM_MMAP_MIN_ADDR).
neverallow * self:memprotect mmap_zero;
# No domain needs mac_override as it is unused by SELinux.
neverallow * self:global_capability2_class_set mac_override;
# Disallow attempts to set contexts not defined in current policy
# This helps guarantee that unknown or dangerous contents will not ever
# be set.
neverallow * self:global_capability2_class_set mac_admin;
# Once the policy has been loaded there shall be none to modify the policy.
# It is sealed.
neverallow * kernel:security load_policy;
# Only init prior to switching context should be able to set enforcing mode.
# init starts in kernel domain and switches to init domain via setcon in
# the init.rc, so the setenforce occurs while still in kernel. After
# switching domains, there is never any need to setenforce again by init.
neverallow * kernel:security setenforce;
neverallow { domain -kernel } kernel:security setcheckreqprot;
# No booleans in AOSP policy, so no need to ever set them.
neverallow * kernel:security setbool;
# Adjusting the AVC cache threshold.
# Not presently allowed to anything in policy, but possibly something
# that could be set from init.rc.
neverallow { domain -init } kernel:security setsecparam;
# Only the kernel hwrng thread should be able to read from the HW RNG.
neverallow {
domain
-prng_seeder # PRNG seeder daemon periodically reseeds itself from HW RNG
-shell # For CTS, restricted to just getattr in shell.te
-ueventd # To create the /dev/hw_random file
} hw_random_device:chr_file *;
# b/78174219 b/64114943
neverallow {
domain
-shell # stat of /dev, getattr only
-ueventd
} keychord_device:chr_file *;
# Ensure that all entrypoint executables are in exec_type or postinstall_file.
neverallow * { file_type -exec_type -postinstall_file }:file entrypoint;
# The dynamic linker always calls access(2) on the path. Don't generate SElinux
# denials since the linker does not actually access the path in case the path
# does not exist or isn't accessible for the process.
dontaudit domain postinstall_mnt_dir:dir audit_access;
#Ensure that nothing in userspace can access /dev/port
neverallow {
domain
-shell # Shell user should not have any abilities outside of getattr
-ueventd
} port_device:chr_file *;
neverallow * port_device:chr_file ~{ create relabelto unlink setattr getattr };
# Only init should be able to configure kernel usermodehelpers or
# security-sensitive proc settings.
neverallow { domain -init } usermodehelper:file { append write };
neverallow { domain -init -ueventd } sysfs_usermodehelper:file { append write };
neverallow { domain -init -vendor_init } proc_security:file { append open read write };
# Init can't do anything with binder calls. If this neverallow rule is being
# triggered, it's probably due to a service with no SELinux domain.
neverallow * init:binder *;
neverallow * vendor_init:binder *;
# Binderfs logs contain sensitive information about other processes.
neverallow { domain -dumpstate -init -vendor_init userdebug_or_eng(`-domain') } { binderfs_logs binderfs_logs_proc }:file no_rw_file_perms;
neverallow { domain -dumpstate -init -vendor_init -system_server } binderfs_logs_stats:file no_rw_file_perms;
# Don't allow raw read/write/open access to block_device
# Rather force a relabel to a more specific type
neverallow { domain -kernel -init -recovery } block_device:blk_file { open read write };
# Do not allow renaming of block files or character files
# Ability to do so can lead to possible use in an exploit chain
# e.g. https://googleprojectzero.blogspot.com/2016/12/chrome-os-exploit-one-byte-overflow-and.html
neverallow * *:{ blk_file chr_file } rename;
# Don't allow raw read/write/open access to generic devices.
# Rather force a relabel to a more specific type.
neverallow domain device:chr_file { open read write };
# Files from cache should never be executed
neverallow domain { cache_file cache_backup_file cache_private_backup_file cache_recovery_file }:file execute;
# The test files and executables MUST not be accessible to any domain
neverallow { domain userdebug_or_eng(`-kernel') } nativetest_data_file:file_class_set no_w_file_perms;
neverallow domain nativetest_data_file:dir no_w_dir_perms;
neverallow { domain userdebug_or_eng(`-shell') } nativetest_data_file:file no_x_file_perms;
neverallow { domain -shell -init -adbd } shell_test_data_file:file_class_set no_w_file_perms;
neverallow { domain -shell -init -adbd } shell_test_data_file:dir no_w_dir_perms;
neverallow { domain -shell -init -adbd -heapprofd -crash_dump } shell_test_data_file:file *;
neverallow heapprofd shell_test_data_file:file { no_w_file_perms no_x_file_perms };
neverallow { domain -shell -init -adbd } shell_test_data_file:sock_file *;
# Only the init property service should write to /data/property and /dev/__properties__
neverallow { domain -init } property_data_file:dir no_w_dir_perms;
neverallow { domain -init } property_data_file:file { no_w_file_perms no_x_file_perms };
neverallow { domain -init } property_type:file { no_w_file_perms no_x_file_perms };
neverallow { domain -init } properties_device:file { no_w_file_perms no_x_file_perms };
neverallow { domain -init } properties_serial:file { no_w_file_perms no_x_file_perms };
# Nobody should be doing writes to /system & /vendor
# These partitions are intended to be read-only and must never be
# modified. Doing so would violate important Android security guarantees
# and invalidate dm-verity signatures.
neverallow {
domain
with_asan(`-asan_extract')
recovery_only(`userdebug_or_eng(`-fastbootd')')
} {
system_file_type
vendor_file_type
exec_type
}:dir_file_class_set { create write setattr relabelfrom append unlink link rename };
neverallow { domain -kernel with_asan(`-asan_extract') } { system_file_type vendor_file_type exec_type }:dir_file_class_set relabelto;
# Don't allow mounting on top of /system files or directories
neverallow * exec_type:dir_file_class_set mounton;
# Nothing should be writing to files in the rootfs.
neverallow * rootfs:file { create write setattr relabelto append unlink link rename };
# Restrict context mounts to specific types marked with
# the contextmount_type attribute.
neverallow * {fs_type -contextmount_type}:filesystem relabelto;
# Ensure that context mount types are not writable, to ensure that
# the write to /system restriction above is not bypassed via context=
# mount to another type.
neverallow * contextmount_type:dir_file_class_set
{ create setattr relabelfrom relabelto append link rename };
neverallow { domain recovery_only(`userdebug_or_eng(`-fastbootd')') } contextmount_type:dir_file_class_set { write unlink };
# Do not allow service_manager add for default service labels.
# Instead domains should use a more specific type such as
# system_app_service rather than the generic type.
# New service_types are defined in {,hw,vnd}service.te and new mappings
# from service name to service_type are defined in {,hw,vnd}service_contexts.
neverallow * default_android_service:service_manager *;
neverallow * default_android_vndservice:service_manager *;
neverallow * default_android_hwservice:hwservice_manager *;
# Looking up the base class/interface of all HwBinder services is a bad idea.
# hwservicemanager currently offer such lookups only to make it so that security
# decisions are expressed in SELinux policy. However, it's unclear whether this
# lookup has security implications. If it doesn't, hwservicemanager should be
# modified to not offer this lookup.
# This rule can be removed if hwservicemanager is modified to not permit these
# lookups.
neverallow * hidl_base_hwservice:hwservice_manager find;
# Require that domains explicitly label unknown properties, and do not allow
# anyone but init to modify unknown properties.
neverallow { domain -init -vendor_init } mmc_prop:property_service set;
neverallow { domain -init -vendor_init } vndk_prop:property_service set;
compatible_property_only(`
neverallow { domain -init } mmc_prop:property_service set;
neverallow { domain -init -vendor_init } exported_default_prop:property_service set;
neverallow { domain -init } exported_secure_prop:property_service set;
neverallow { domain -init -vendor_init } vendor_default_prop:property_service set;
neverallow { domain -init -vendor_init } storage_config_prop:property_service set;
neverallow { domain -init -vendor_init } hw_timeout_multiplier_prop:property_service set;
')
compatible_property_only(`
neverallow { domain -init -system_server -vendor_init } exported_pm_prop:property_service set;
neverallow { domain -coredomain -vendor_init } exported_pm_prop:file no_rw_file_perms;
')
# New "pm.dexopt." sysprops should be explicitly listed as exported_pm_prop.
neverallow { domain -init -dumpstate -vendor_init } future_pm_prop:property_service set;
neverallow { domain -init -dumpstate -vendor_init } future_pm_prop:file no_rw_file_perms;
# ART may introduce new sysprops. SELinux denials due to reading new sysprops on
# old platforms shouldn't be regarded as a problem.
dontaudit domain future_pm_prop:file read;
neverallow { domain -init } aac_drc_prop:property_service set;
neverallow { domain -init } build_prop:property_service set;
neverallow { domain -init } userdebug_or_eng_prop:property_service set;
# Do not allow reading device's serial number from system properties except form
# a few allowed domains.
neverallow {
domain
-adbd
-dumpstate
-fastbootd
-hal_camera_server
-hal_cas_server
-hal_drm_server
-hal_keymint_server
userdebug_or_eng(`-incidentd')
-init
-mediadrmserver
-mediaserver
-recovery
-shell
-system_server
-vendor_init
} serialno_prop:file r_file_perms;
neverallow {
domain
-init
-recovery
-system_server
-ueventd # Further restricted in ueventd.te
} frp_block_device:blk_file no_rw_file_perms;
# The metadata block device is set aside for device encryption and
# verified boot metadata. It may be reset at will and should not
# be used by other domains.
neverallow {
domain
-init
-recovery
-vold
-e2fs
-fsck
-fastbootd
-hal_fastboot_server
} metadata_block_device:blk_file { append link rename write open read ioctl lock };
# No domain other than recovery, update_engine and fastbootd can write to system partition(s).
neverallow {
domain
-fastbootd
userdebug_or_eng(`-fsck')
userdebug_or_eng(`-init')
-recovery
-update_engine
} system_block_device:blk_file { write append };
# Only (hw|vnd|)servicemanager should be able to register with binder as the context manager
neverallow { domain -servicemanager -hwservicemanager -vndservicemanager } *:binder set_context_mgr;
# The service managers are only allowed to access their own device node
neverallow servicemanager hwbinder_device:chr_file no_rw_file_perms;
neverallow servicemanager vndbinder_device:chr_file no_rw_file_perms;
neverallow hwservicemanager binder_device:chr_file no_rw_file_perms;
neverallow hwservicemanager vndbinder_device:chr_file no_rw_file_perms;
neverallow vndservicemanager binder_device:chr_file no_rw_file_perms;
neverallow vndservicemanager hwbinder_device:chr_file no_rw_file_perms;
full_treble_only(`
# Vendor apps are permited to use only stable public services. If they were to use arbitrary
# services which can change any time framework/core is updated, breakage is likely.
#
# Note, this same logic applies to untrusted apps, but neverallows for these are separate.
neverallow {
appdomain
-coredomain
} {
service_manager_type
-app_api_service
-ephemeral_app_api_service
-hal_service_type # see app_neverallows.te
-apc_service
-audioserver_service # TODO(b/36783122) remove exemptions below once app_api_service is fixed
-cameraserver_service
-drmserver_service
-credstore_service
-keystore_maintenance_service
-keystore_service
-legacykeystore_service
-mediadrmserver_service
-mediaextractor_service
-mediametrics_service
-mediaserver_service
-nfc_service
-radio_service
-virtual_touchpad_service
-vr_manager_service
userdebug_or_eng(`-hal_face_service')
}:service_manager find;
')
# On full TREBLE devices, only vendor components, shell, and su can use VendorBinder.
full_treble_only(`
neverallow {
coredomain
-shell
userdebug_or_eng(`-su')
-ueventd # uevent is granted create for this device, but we still neverallow I/O below
} vndbinder_device:chr_file rw_file_perms;
')
full_treble_only(`
neverallow ueventd vndbinder_device:chr_file { read write append ioctl };
')
full_treble_only(`
neverallow {
coredomain
-shell
userdebug_or_eng(`-su')
} vndservice_manager_type:service_manager *;
')
full_treble_only(`
neverallow {
coredomain
-shell
userdebug_or_eng(`-su')
} vndservicemanager:binder *;
')
# On full TREBLE devices, socket communications between core components and vendor components are
# not permitted.
# Most general rules first, more specific rules below.
# Core domains are not permitted to initiate communications to vendor domain sockets.
# We are not restricting the use of already established sockets because it is fine for a process
# to obtain an already established socket via some public/official/stable API and then exchange
# data with its peer over that socket. The wire format in this scenario is dicatated by the API
# and thus does not break the core-vendor separation.
full_treble_only(`
neverallow_establish_socket_comms({
coredomain
-init
-adbd
}, {
domain
-coredomain
-socket_between_core_and_vendor_violators
});
')
# Vendor domains are not permitted to initiate create/open sockets owned by core domains
full_treble_only(`
neverallow {
domain
-coredomain
-appdomain # appdomain restrictions below
-data_between_core_and_vendor_violators # b/70393317
-socket_between_core_and_vendor_violators
-vendor_init
} {
coredomain_socket
core_data_file_type
unlabeled # used only by core domains
}:sock_file ~{ append getattr ioctl read write };
')
full_treble_only(`
neverallow {
appdomain
-coredomain
} {
coredomain_socket
unlabeled # used only by core domains
core_data_file_type
-app_data_file
-privapp_data_file
-pdx_endpoint_socket_type # used by VR layer
-pdx_channel_socket_type # used by VR layer
}:sock_file ~{ append getattr ioctl read write };
')
# Core domains are not permitted to create/open sockets owned by vendor domains
full_treble_only(`
neverallow {
coredomain
-init
-ueventd
-socket_between_core_and_vendor_violators
} {
file_type
dev_type
-coredomain_socket
-core_data_file_type
-app_data_file_type
-unlabeled
}:sock_file ~{ append getattr ioctl read write };
')
# On TREBLE devices, vendor and system components are only allowed to share
# files by passing open FDs over hwbinder. Ban all directory access and all file
# accesses other than what can be applied to an open FD such as
# ioctl/stat/read/write/append. This is enforced by segregating /data.
# Vendor domains may directly access file in /data/vendor by path, but may only
# access files outside of /data/vendor via an open FD passed over hwbinder.
# Likewise, core domains may only directly access files outside /data/vendor by
# path and files in /data/vendor by open FD.
full_treble_only(`
# only coredomains may only access core_data_file_type, particularly not
# /data/vendor
neverallow {
coredomain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-data_between_core_and_vendor_violators
-init
-vold_prepare_subdirs
} {
data_file_type
-core_data_file_type
-app_data_file_type
}:file_class_set ~{ append getattr ioctl read write map };
')
full_treble_only(`
neverallow {
coredomain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-data_between_core_and_vendor_violators
-init
-vold_prepare_subdirs
} {
data_file_type
-core_data_file_type
-app_data_file_type
# TODO(b/72998741) Remove exemption. Further restricted in a subsequent
# neverallow. Currently only getattr and search are allowed.
-vendor_data_file
}:dir *;
')
full_treble_only(`
# vendor domains may only access files in /data/vendor, never core_data_file_types
neverallow {
domain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-coredomain
-data_between_core_and_vendor_violators # TODO(b/34980020) Remove once all violators have been cleaned up
-vendor_init
} {
core_data_file_type
with_native_coverage(`-method_trace_data_file')
}:file_class_set ~{ append getattr ioctl read write map };
neverallow {
vendor_init
-data_between_core_and_vendor_violators
} {
core_data_file_type
-unencrypted_data_file
with_native_coverage(`-method_trace_data_file')
}:file_class_set ~{ append getattr ioctl read write map };
# vendor init needs to be able to read unencrypted_data_file to create directories with FBE.
# The vendor init binary lives on the system partition so there is not a concern with stability.
neverallow vendor_init unencrypted_data_file:file ~r_file_perms;
')
full_treble_only(`
# vendor domains may only access dirs in /data/vendor, never core_data_file_types
neverallow {
domain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-coredomain
-data_between_core_and_vendor_violators
-vendor_init
} {
core_data_file_type
-system_data_file # default label for files on /data. Covered below...
-system_data_root_file
-vendor_userdir_file
-vendor_data_file
with_native_coverage(`-method_trace_data_file')
}:dir *;
neverallow {
vendor_init
-data_between_core_and_vendor_violators
} {
core_data_file_type
-unencrypted_data_file
-system_data_file
-system_data_root_file
-vendor_userdir_file
-vendor_data_file
with_native_coverage(`-method_trace_data_file')
}:dir *;
# vendor init needs to be able to read unencrypted_data_file to create directories with FBE.
# The vendor init binary lives on the system partition so there is not a concern with stability.
neverallow vendor_init unencrypted_data_file:dir ~search;
')
full_treble_only(`
# vendor domains may only access dirs in /data/vendor, never core_data_file_types
neverallow {
domain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-coredomain
-data_between_core_and_vendor_violators # TODO(b/34980020) Remove once all violators have been cleaned up
} {
system_data_file # default label for files on /data. Covered below
}:dir ~{ getattr search };
')
full_treble_only(`
# coredomains may not access dirs in /data/vendor.
neverallow {
coredomain
-data_between_core_and_vendor_violators # TODO(b/34980020) Remove once all violators have been cleaned up
-init
-vold # vold creates per-user storage for both system and vendor
-vold_prepare_subdirs
} {
vendor_data_file # default label for files on /data. Covered below
}:dir ~{ getattr search };
')
full_treble_only(`
# coredomains may not access dirs in /data/vendor.
neverallow {
coredomain
-data_between_core_and_vendor_violators # TODO(b/34980020) Remove once all violators have been cleaned up
-init
} {
vendor_data_file # default label for files on /data/vendor{,_ce,_de}.
}:file_class_set ~{ append getattr ioctl read write map };
')
full_treble_only(`
# Non-vendor domains are not allowed to file execute shell
# from vendor
neverallow {
coredomain
-init
-shell
-ueventd
} vendor_shell_exec:file { execute execute_no_trans };
')
full_treble_only(`
# Do not allow vendor components to execute files from system
# except for the ones allowed here.
neverallow {
domain
-coredomain
-appdomain
-vendor_executes_system_violators
-vendor_init
} {
system_file_type
-system_lib_file
-system_linker_exec
-crash_dump_exec
-netutils_wrapper_exec
userdebug_or_eng(`-tcpdump_exec')
# Vendor components still can invoke shell commands via /system/bin/sh
-shell_exec
-toolbox_exec
}:file { entrypoint execute execute_no_trans };
')
full_treble_only(`
# Do not allow coredomain to access entrypoint for files other
# than system_file_type and postinstall_file
neverallow coredomain {
file_type
-system_file_type
-postinstall_file
}:file entrypoint;
# Do not allow domains other than coredomain to access entrypoint
# for anything but vendor_file_type and init_exec for vendor_init.
neverallow { domain -coredomain } {
file_type
-vendor_file_type
-init_exec
}:file entrypoint;
')
full_treble_only(`
# Do not allow system components to execute files from vendor
# except for the ones allowed here.
neverallow {
coredomain
-init
-shell
-system_executes_vendor_violators
-ueventd
} {
vendor_file_type
-same_process_hal_file
-vndk_sp_file
-vendor_app_file
-vendor_public_framework_file
-vendor_public_lib_file
}:file execute;
')
full_treble_only(`
neverallow {
coredomain
-shell
-system_executes_vendor_violators
} {
vendor_file_type
-same_process_hal_file
}:file execute_no_trans;
')
full_treble_only(`
# Do not allow vendor components access to /system files except for the
# ones allowed here.
neverallow {
domain
-appdomain
-coredomain
-vendor_executes_system_violators
# vendor_init needs access to init_exec for domain transition. vendor_init
# neverallows are covered in public/vendor_init.te
-vendor_init
} {
system_file_type
-crash_dump_exec
-file_contexts_file
-netutils_wrapper_exec
-property_contexts_file
-system_event_log_tags_file
-system_group_file
-system_lib_file
with_asan(`-system_asan_options_file')
-system_linker_exec
-system_linker_config_file
-system_passwd_file
-system_seccomp_policy_file
-system_security_cacerts_file
-system_zoneinfo_file
-task_profiles_api_file
-task_profiles_file
userdebug_or_eng(`-tcpdump_exec')
# Vendor components still can invoke shell commands via /system/bin/sh
-shell_exec
-toolbox_exec
}:file *;
')
# Only system_server should be able to send commands via the zygote socket
neverallow { domain -zygote -system_server } zygote:unix_stream_socket connectto;
neverallow { domain -system_server } zygote_socket:sock_file write;
neverallow { domain -system_server -webview_zygote -app_zygote } webview_zygote:unix_stream_socket connectto;
neverallow { domain -system_server } webview_zygote:sock_file write;
neverallow { domain -system_server } app_zygote:sock_file write;
neverallow domain tombstoned_crash_socket:unix_stream_socket connectto;
# Never allow anyone except dumpstate, incidentd, or the system server to connect or write to
# the tombstoned intercept socket.
neverallow { domain -dumpstate -incidentd -system_server } tombstoned_intercept_socket:sock_file write;
neverallow { domain -dumpstate -incidentd -system_server } tombstoned_intercept_socket:unix_stream_socket connectto;
# Never allow anyone but system_server to read heapdumps in /data/system/heapdump.
neverallow { domain -init -system_server } heapdump_data_file:file read;
# Android does not support System V IPCs.
#
# The reason for this is due to the fact that, by design, they lead to global
# kernel resource leakage.
#
# For example, there is no way to automatically release a SysV semaphore
# allocated in the kernel when:
#
# - a buggy or malicious process exits
# - a non-buggy and non-malicious process crashes or is explicitly killed.
#
# Killing processes automatically to make room for new ones is an
# important part of Android's application lifecycle implementation. This means
# that, even assuming only non-buggy and non-malicious code, it is very likely
# that over time, the kernel global tables used to implement SysV IPCs will fill
# up.
neverallow * *:{ shm sem msg msgq } *;
# Do not mount on top of symlinks, fifos, or sockets.
# Feature parity with Chromium LSM.
neverallow * { file_type fs_type dev_type }:{ lnk_file fifo_file sock_file } mounton;
# Nobody should be able to execute su on user builds.
# On userdebug/eng builds, only dumpstate, shell, and
# su itself execute su.
neverallow { domain userdebug_or_eng(`-dumpstate -shell -su') } su_exec:file no_x_file_perms;
# Do not allow the introduction of new execmod rules. Text relocations
# and modification of executable pages are unsafe.
# The only exceptions are for NDK text relocations associated with
# https://code.google.com/p/android/issues/detail?id=23203
# which, long term, need to go away.
neverallow * {
file_type
-apk_data_file
-app_data_file
-asec_public_file
}:file execmod;
# Do not allow making the stack or heap executable.
# We would also like to minimize execmem but it seems to be
# required by some device-specific service domains.
neverallow * self:process { execstack execheap };
# Do not allow the introduction of new execmod rules. Text relocations
# and modification of executable pages are unsafe.
neverallow { domain -untrusted_app_25 -untrusted_app_27 } file_type:file execmod;
# Ensure that all types assigned to processes are included
# in the domain attribute, so that all allow and neverallow rules
# written on domain are applied to all processes.
# This is achieved by ensuring that it is impossible to transition
# from a domain to a non-domain type and vice versa.
# TODO - rework this: neverallow domain ~domain:process { transition dyntransition };
neverallow ~domain domain:process { transition dyntransition };
#
# Only system_app and system_server should be creating or writing
# their files. The proper way to share files is to setup
# type transitions to a more specific type or assigning a type
# to its parent directory via a file_contexts entry.
# Example type transition:
# mydomain.te:file_type_auto_trans(mydomain, system_data_file, new_file_type)
#
neverallow {
domain
-system_server
-system_app
-init
-toolbox # TODO(b/141108496) We want to remove toolbox
-installd # for relabelfrom and unlink, check for this in explicit neverallow
-vold_prepare_subdirs # For unlink
with_asan(`-asan_extract')
} system_data_file:file no_w_file_perms;
# do not grant anything greater than r_file_perms and relabelfrom unlink
# to installd
neverallow installd system_data_file:file ~{ r_file_perms relabelfrom unlink };
#
# Only these domains should transition to shell domain. This domain is
# permissible for the "shell user". If you need a process to exec a shell
# script with differing privilege, define a domain and set up a transition.
#
neverallow {
domain
-adbd
-init
-runas
-zygote
} shell:process { transition dyntransition };
# Only domains spawned from zygote, runas and simpleperf_app_runner may have
# the appdomain attribute. simpleperf is excluded as a domain transitioned to
# when running an app-scoped profiling session.
neverallow { domain -simpleperf_app_runner -runas -app_zygote -webview_zygote -zygote } {
appdomain -shell -simpleperf userdebug_or_eng(`-su')
}:process { transition dyntransition };
# Minimize read access to shell- or app-writable symlinks.
# This is to prevent malicious symlink attacks.
neverallow {
domain
-appdomain
-artd
-installd
} { app_data_file privapp_data_file }:lnk_file read;
neverallow {
domain
-shell
userdebug_or_eng(`-uncrypt')
-installd
} shell_data_file:lnk_file read;
# servicemanager and vndservicemanager are the only processes which handle the
# service_manager list request
neverallow * ~{
servicemanager
vndservicemanager
}:service_manager list;
# hwservicemanager is the only process which handles hw list requests
neverallow * ~{
hwservicemanager
}:hwservice_manager list;
# only service_manager_types can be added to service_manager
# TODO - rework this: neverallow * ~service_manager_type:service_manager { add find };
# Prevent assigning non property types to properties
# TODO - rework this: neverallow * ~property_type:property_service set;
# Domain types should never be assigned to any files other
# than the /proc/pid files associated with a process. The
# executable file used to enter a domain should be labeled
# with its own _exec type, not with the domain type.
# Conventionally, this looks something like:
# $ cat mydaemon.te
# type mydaemon, domain;
# type mydaemon_exec, exec_type, file_type;
# init_daemon_domain(mydaemon)
# $ grep mydaemon file_contexts
# /system/bin/mydaemon -- u:object_r:mydaemon_exec:s0
neverallow * domain:file { execute execute_no_trans entrypoint };
# Do not allow access to the generic debugfs label. This is too broad.
# Instead, if access to part of debugfs is desired, it should have a
# more specific label.
# TODO: fix dumpstate
neverallow { domain -init -vendor_init -dumpstate } debugfs:{ file lnk_file } no_rw_file_perms;
# Do not allow executable files in debugfs.
neverallow domain debugfs_type:file { execute execute_no_trans };
# Don't allow access to the FUSE control filesystem, except to vold and init's
neverallow { domain -vold -init -vendor_init } fusectlfs:file no_rw_file_perms;
# Profiles contain untrusted data and profman parses that. We should only run
# it from installd and artd forked processes.
neverallow {
domain
-installd
-profman
-artd
} profman_exec:file no_x_file_perms;
# Enforce restrictions on kernel module origin.
# Do not allow kernel module loading except from system,
# vendor, boot, and system_dlkm partitions.
# TODO(b/218951883): Remove usage of system and rootfs as origin
neverallow * ~{ system_file_type vendor_file_type rootfs system_dlkm_file_type }:system module_load;
# Only allow filesystem caps to be set at build time. Runtime changes
# to filesystem capabilities are not permitted.
neverallow * self:global_capability_class_set setfcap;
# Enforce AT_SECURE for executing crash_dump.
neverallow domain crash_dump:process noatsecure;
# Do not permit non-core domains to register HwBinder services which are
# guaranteed to be provided by core domains only.
neverallow ~coredomain coredomain_hwservice:hwservice_manager add;
# Do not permit the registeration of HwBinder services which are guaranteed to
# be passthrough only (i.e., run in the process of their clients instead of a
# separate server process).
neverallow * same_process_hwservice:hwservice_manager add;
# If an already existing file is opened with O_CREAT, the kernel might generate
# a false report of a create denial. Silence these denials and make sure that
# inappropriate permissions are not granted.
# These filesystems don't allow files or directories to be created, so the permission
# to do so should never be granted.
neverallow domain {
proc_type
sysfs_type
}:dir { add_name create link remove_name rename reparent rmdir write };
# cgroupfs directories can be created, but not files within them.
neverallow domain cgroup:file create;
neverallow domain cgroup_v2:file create;
dontaudit domain proc_type:dir write;
dontaudit domain sysfs_type:dir write;
dontaudit domain cgroup:file create;
dontaudit domain cgroup_v2:file create;
# These are only needed in permissive mode - in enforcing mode the
# directory write check fails and so these are never attempted.
userdebug_or_eng(`
dontaudit domain proc_type:dir add_name;
dontaudit domain sysfs_type:dir add_name;
dontaudit domain proc_type:file create;
dontaudit domain sysfs_type:file create;
')
# Platform must not have access to /mnt/vendor.
neverallow {
coredomain
-init
-ueventd
-vold
-system_writes_mnt_vendor_violators
} mnt_vendor_file:dir *;
# Only apps are allowed access to vendor public libraries.
full_treble_only(`
neverallow {
coredomain
-appdomain
} {vendor_public_framework_file vendor_public_lib_file}:file { execute execute_no_trans };
')
# Vendor domian must not have access to /mnt/product.
neverallow {
domain
-coredomain
} mnt_product_file:dir *;
# Platform must not have access to sysfs_batteryinfo, but should do it via health HAL
full_treble_only(`
neverallow {
coredomain
-shell
# For access to block device information under /sys/class/block.
-apexd
# Read sysfs block device information.
-init
# Generate uevents for health info
-ueventd
# Recovery uses health HAL passthrough implementation.
-recovery
# Charger uses health HAL passthrough implementation.
-charger
# TODO(b/110891300): remove this exception
-incidentd
} sysfs_batteryinfo:file { open read };
')
neverallow {
domain
-hal_codec2_server
-hal_omx_server
} hal_codec2_hwservice:hwservice_manager add;
# Only apps targetting < Q are allowed to open /dev/ashmem directly.
# Apps must use ASharedMemory NDK API. Native code must use libcutils API.
neverallow {
domain
-ephemeral_app # We don't distinguish ephemeral apps based on target API.
-untrusted_app_25
-untrusted_app_27
} ashmem_device:chr_file open;
neverallow { domain -traced_probes -init -vendor_init } debugfs_tracing_printk_formats:file *;
# No domains other than a select few can access the misc_block_device. This
# block device is reserved for OTA use.
# Do not assert this rule on userdebug/eng builds, due to some devices using
# this partition for testing purposes.
neverallow {
domain
userdebug_or_eng(`-domain') # exclude debuggable builds
-fastbootd
-hal_bootctl_server
-init
-uncrypt
-update_engine
-vendor_init
-vendor_misc_writer
-vold
-recovery
-ueventd
-mtectrl
-misctrl
-kcmdlinectrl
} misc_block_device:blk_file { append link relabelfrom rename write open read ioctl lock };
# Limit ability to ptrace or read sensitive /proc/pid files of processes
# with other UIDs to these allowlisted domains.
neverallow {
domain
-vold
userdebug_or_eng(`-llkd')
-dumpstate
userdebug_or_eng(`-incidentd')
userdebug_or_eng(`-profcollectd')
userdebug_or_eng(`-simpleperf_boot')
-storaged
-system_server
} self:global_capability_class_set sys_ptrace;
# Limit ability to generate hardware unique device ID attestations to priv_apps
neverallow { domain -priv_app -gmscore_app } *:keystore2_key gen_unique_id;
neverallow { domain -system_server } *:keystore2_key use_dev_id;
neverallow { domain -system_server } keystore:keystore2 { clear_ns lock reset unlock };
neverallow {
domain
-init
-vendor_init
userdebug_or_eng(`-domain')
} debugfs_tracing_debug:file no_rw_file_perms;
# System_server owns dropbox data, and init creates/restorecons the directory
# Disallow direct access by other processes.
neverallow {
domain
-init
-system_server
userdebug_or_eng(`-dumpstate')
} dropbox_data_file:dir *;
neverallow {
domain
-init
-system_server
userdebug_or_eng(`-dumpstate')
} dropbox_data_file:file ~{ getattr read };
###
# Services should respect app sandboxes
neverallow {
domain
-appdomain
-artd # compile secondary dex files
-installd # creation of sandbox
} {
privapp_data_file
app_data_file
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `storage_area_content_file')
}:dir_file_class_set { create unlink };
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `
neverallow {
domain
-artd # compile secondary dex files
-installd # creation of sandbox
-vold_prepare_subdirs # creation of storage area directories
} {storage_area_app_dir storage_area_dir }:dir { create unlink };
')
# Only the following processes should be directly accessing private app
# directories.
neverallow {
domain
-adbd
-appdomain
-app_zygote
-artd # compile secondary dex files
-dexoptanalyzer
-installd
-profman
-rs # spawned by appdomain, so carryover the exception above
-runas
-system_server
-zygote
} {
privapp_data_file
app_data_file
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `storage_area_content_file')
}:dir *;
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `
neverallow {
domain
-appdomain
-app_zygote
-artd # compile secondary dex files
-installd
-rs # spawned by appdomain, so carryover the exception above
-system_server
-vold # encryption of storage area directories
-vold_prepare_subdirs # creation of storage area directories
-zygote
} { storage_area_dir storage_area_app_dir }:dir *;
')
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `
# only vold and installd can access the storage area key files
# (and init, in case of a recursive restorecon)
neverallow {
domain
-init
-vold
-vold_prepare_subdirs
-installd
} { storage_area_key_file }:dir_file_class_set *;
')
# Only apps should be modifying app data. installd is exempted for
# restorecon and package install/uninstall.
neverallow {
domain
-appdomain
-artd # compile secondary dex files
-installd
-rs # spawned by appdomain, so carryover the exception above
} {
privapp_data_file
app_data_file
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `storage_area_content_file')
}:dir ~r_dir_perms;
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `
neverallow {
domain
-appdomain
-artd # compile secondary dex files
-installd
-rs # spawned by appdomain, so carryover the exception above
-vold_prepare_subdirs # creation of storage area directories
} { storage_area_dir storage_area_app_dir }:dir ~r_dir_perms;
')
neverallow {
domain
-appdomain
-app_zygote
-artd # compile secondary dex files
-installd
-rs # spawned by appdomain, so carryover the exception above
} {
privapp_data_file
app_data_file
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `storage_area_content_file')
}:file_class_set open;
neverallow {
domain
-appdomain
-artd # compile secondary dex files
-installd # creation of sandbox
} {
privapp_data_file
app_data_file
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `storage_area_content_file')
}:dir_file_class_set { create unlink };
neverallow {
domain
-artd # compile secondary dex files
-installd
} {
privapp_data_file
app_data_file
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `storage_area_content_file')
}:dir_file_class_set { relabelfrom relabelto };
is_flag_enabled(RELEASE_UNLOCKED_STORAGE_API, `
neverallow {
domain
-artd # compile secondary dex files
-installd
-vold_prepare_subdirs
} { storage_area_dir storage_area_app_dir }:dir { relabelfrom relabelto };
')
# The staging directory contains APEX and APK files. It is important to ensure
# that these files cannot be accessed by other domains to ensure that the files
# do not change between system_server staging the files and apexd processing
# the files.
neverallow {
domain
-init
-system_server
-apexd
-installd
-priv_app
-virtualizationmanager
} staging_data_file:dir *;
neverallow {
domain
-init
-system_app
-system_server
-apexd
-adbd
-kernel
-installd
-priv_app
-shell
-virtualizationmanager
-crosvm
} staging_data_file:file *;
neverallow { domain -init -system_server -installd} staging_data_file:dir no_w_dir_perms;
# apexd needs the link and unlink permissions, so list every `no_w_file_perms`
# except for `link` and `unlink`.
neverallow { domain -init -system_server } staging_data_file:file
{ append create relabelfrom rename setattr write no_x_file_perms };
neverallow {
domain
-appdomain # for oemfs
-bootanim # for oemfs
-recovery # for /tmp/update_binary in tmpfs
} { fs_type -rootfs }:file execute;
#
# Assert that, to the extent possible, we're not loading executable content from
# outside the rootfs or /system partition except for a few allowlisted domains.
# Executable files loaded from /data is a persistence vector
# we want to avoid. See
# https://bugs.chromium.org/p/project-zero/issues/detail?id=955 for example.
#
neverallow {
domain
-appdomain
with_asan(`-asan_extract')
-shell
userdebug_or_eng(`-su')
-system_server_startup # for memfd backed executable regions
-app_zygote
-webview_zygote
-zygote
userdebug_or_eng(`-mediaextractor')
userdebug_or_eng(`-mediaswcodec')
} {
file_type
-system_file_type
-system_lib_file
-system_linker_exec
-vendor_file_type
-exec_type
-postinstall_file
}:file execute;
# Only init is allowed to write cgroup.rc file
neverallow {
domain
-init
-vendor_init
} cgroup_rc_file:file no_w_file_perms;
# Only authorized processes should be writing to files in /data/dalvik-cache
neverallow {
domain
-init # TODO: limit init to relabelfrom for files
-zygote
-installd
-postinstall_dexopt
-cppreopts
-dex2oat
-otapreopt_slot
-artd
} dalvikcache_data_file:file no_w_file_perms;
neverallow {
domain
-init
-installd
-postinstall_dexopt
-cppreopts
-dex2oat
-zygote
-otapreopt_slot
-artd
} dalvikcache_data_file:dir no_w_dir_perms;
# Only authorized processes should be writing to /data/misc/apexdata/com.android.art as it
# contains boot class path and system server AOT artifacts following an ART APEX Mainline update.
neverallow {
domain
# art-related processes
-composd
-compos_fd_server
-odrefresh
-odsign
# others
-apexd
-init
-vold_prepare_subdirs
} apex_art_data_file:file no_w_file_perms;
neverallow {
domain
# art-related processes
-composd
-compos_fd_server
-odrefresh
-odsign
# others
-apexd
-init
-vold_prepare_subdirs
} apex_art_data_file:dir no_w_dir_perms;
# Protect most domains from executing arbitrary content from /data.
neverallow {
domain
-appdomain
} {
data_file_type
-apex_art_data_file
-dalvikcache_data_file
-system_data_file # shared libs in apks
-apk_data_file
}:file no_x_file_perms;
# Minimize dac_override and dac_read_search.
# Instead of granting them it is usually better to add the domain to
# a Unix group or change the permissions of a file.
define(`dac_override_allowed', `{
apexd
artd
dnsmasq
dumpstate
init
installd
userdebug_or_eng(`llkd')
lmkd
migrate_legacy_obb_data
netd
postinstall_dexopt
recovery
rss_hwm_reset
sdcardd
tee
ueventd
uncrypt
vendor_init
vold
vold_prepare_subdirs
zygote
}')
neverallow ~dac_override_allowed self:global_capability_class_set dac_override;
# Since the kernel checks dac_read_search before dac_override, domains that
# have dac_override should also have dac_read_search to eliminate spurious
# denials. Some domains have dac_read_search without having dac_override, so
# this list should be a superset of the one above.
neverallow ~{
dac_override_allowed
traced_perf
traced_probes
heapprofd
} self:global_capability_class_set dac_read_search;
# Limit what domains can mount filesystems or change their mount flags.
# sdcard_type (including vfat and exfat) and fusefs_type are exempt as a larger
# set of domains need this capability, including device-specific domains.
neverallow {
domain
-apexd
-dexopt_chroot_setup
recovery_only(`-fastbootd')
-init
-kernel
-otapreopt_chroot
-recovery
-update_engine
-vold
-zygote
} { fs_type
-sdcard_type
-fusefs_type
}:filesystem { mount remount relabelfrom relabelto };
enforce_debugfs_restriction(`
neverallow {
domain userdebug_or_eng(`-init')
} { debugfs_type -debugfs_tracing_debug }:filesystem { mount remount relabelfrom relabelto };
')
# Limit raw I/O to these allowlisted domains. Do not apply to debug builds.
neverallow {
domain
userdebug_or_eng(`-domain')
-kernel
-gsid
-init
-recovery
-ueventd
-uncrypt
-tee
-hal_bootctl_server
-fastbootd
} self:global_capability_class_set sys_rawio;
# Limit directory operations that doesn't need to do app data isolation.
neverallow {
domain
-fsck
-init
-installd
-zygote
} mirror_data_file:dir *;
# This property is being removed. Remove remaining access.
neverallow { domain -init -system_server -vendor_init } net_dns_prop:property_service set;
neverallow { domain -dumpstate -init -system_server -vendor_init } net_dns_prop:file read;
# Only core domains are allowed to access package_manager properties
neverallow { domain -init -system_server } pm_prop:property_service set;
neverallow { domain -coredomain } pm_prop:file no_rw_file_perms;
# Do not allow reading the last boot timestamp from system properties
neverallow { domain -init -system_server -dumpstate } firstboot_prop:file r_file_perms;
# Allow ART to set its config properties in its oneshot boot service, in
# addition to the common init and vendor_init access.
neverallow { domain -art_boot -init -vendor_init } dalvik_config_prop:property_service set;
# Kprobes should only be used by adb root
neverallow { domain -init -vendor_init } debugfs_kprobes:file *;
# On TREBLE devices, most coredomains should not access vendor_files.
# TODO(b/71553434): Remove exceptions here.
full_treble_only(`
neverallow {
coredomain
-appdomain
-bootanim
-crash_dump
-heapprofd
userdebug_or_eng(`-profcollectd')
-init
-kernel
userdebug_or_eng(`-simpleperf_boot')
-traced_perf
-ueventd
} vendor_file:file { no_w_file_perms no_x_file_perms open };
')
# Vendor domains are not permitted to initiate communications to core domain sockets
full_treble_only(`
neverallow_establish_socket_comms({
domain
-coredomain
-appdomain
-socket_between_core_and_vendor_violators
}, {
coredomain
-logd # Logging by writing to logd Unix domain socket is public API
-netd # netdomain needs this
-mdnsd # netdomain needs this
-prng_seeder # Any process using libcrypto needs this
userdebug_or_eng(`-su') # communications with su are permitted only on userdebug or eng builds
-init
-tombstoned # linker to tombstoned
-heapprofd
-traced
-traced_perf
});
')
full_treble_only(`
# Do not allow system components access to /vendor files except for the
# ones allowed here.
neverallow {
coredomain
# TODO(b/37168747): clean up fwk access to /vendor
-crash_dump
-crosvm # loads vendor-specific disk images
-init # starts vendor executables
-kernel # loads /vendor/firmware
-heapprofd
userdebug_or_eng(`-profcollectd')
-shell
userdebug_or_eng(`-simpleperf_boot')
-system_executes_vendor_violators
-traced_perf # library/binary access for symbolization
-ueventd # reads /vendor/ueventd.rc
-vold # loads incremental fs driver
} {
vendor_file_type
-same_process_hal_file
-vendor_app_file
-vendor_apex_file
-vendor_apex_metadata_file
-vendor_boot_ota_file
-vendor_configs_file
-vendor_microdroid_file
-vendor_service_contexts_file
-vendor_framework_file
-vendor_idc_file
-vendor_keychars_file
-vendor_keylayout_file
-vendor_overlay_file
-vendor_public_framework_file
-vendor_public_lib_file
-vendor_task_profiles_file
-vendor_uuid_mapping_config_file
-vndk_sp_file
-vendor_aconfig_storage_file
}:file *;
')
# mlsvendorcompat is only for compatibility support for older vendor
# images, and should not be granted to any domain in current policy.
# (Every domain is allowed self:fork, so this will trigger if the
# intsersection of domain & mlsvendorcompat is not empty.)
neverallow domain mlsvendorcompat:process fork;
# Only init and otapreopt_chroot should be mounting filesystems on locations
# labeled system or vendor (/product and /vendor respectively).
neverallow { domain -dexopt_chroot_setup -init -otapreopt_chroot } { system_file_type vendor_file_type }:dir_file_class_set mounton;
# Only allow init and vendor_init to read/write mm_events properties
# NOTE: dumpstate is allowed to read any system property
neverallow {
domain
-init
-vendor_init
-dumpstate
} mm_events_config_prop:file no_rw_file_perms;
# Allow the tracing daemon and callstack sampler to use kallsyms to symbolize
# kernel traces. Addresses are not disclosed, they are repalced with symbol
# names (if available). Traces don't disclose KASLR.
neverallow {
domain
-init
userdebug_or_eng(`-profcollectd')
-vendor_init
userdebug_or_eng(`-simpleperf_boot')
-traced_probes
-traced_perf
} proc_kallsyms:file { open read };
# debugfs_kcov type is not included in this neverallow statement since the KCOV
# tool uses it for kernel fuzzing.
# vendor_modprobe is also exempted since the kernel modules it loads may create
# debugfs files in its context.
enforce_debugfs_restriction(`
neverallow {
domain
-vendor_modprobe
userdebug_or_eng(`
-init
-hal_dumpstate
-incidentd
')
} { debugfs_type
userdebug_or_eng(`-debugfs_kcov')
-tracefs_type
}:file no_rw_file_perms;
')
# Restrict write access to etm sysfs interface.
neverallow { domain -ueventd -vendor_init } sysfs_devices_cs_etm:file no_w_file_perms;
# Restrict CAP_PERFMON.
neverallow {
domain
-init
-vendor_modprobe
userdebug_or_eng(`-simpleperf_boot')
-kernel
-uprobestats
} self:capability2 perfmon;
# Restrict direct access to shell owned files. The /data/local/tmp directory is
# untrustworthy, and non-allowed domains should not be trusting any content in
# those directories. We allow shell files to be passed around by file
# descriptor, but not directly opened.
# artd doesn't need to access /data/local/tmp, but it needs to access
# /data/{user,user_de}/<user-id>/com.android.shell/... for compiling secondary
# dex files.
neverallow {
domain
-adbd
-appdomain
-artd
-dumpstate
-installd
userdebug_or_eng(`-aconfigd')
userdebug_or_eng(`-uncrypt')
userdebug_or_eng(`-virtualizationmanager')
userdebug_or_eng(`-virtualizationservice')
userdebug_or_eng(`-crosvm')
} shell_data_file:file open;
# In addition to the symlink reading restrictions above, restrict
# write access to shell owned directories. The /data/local/tmp
# directory is untrustworthy, and non-allowed domains should
# not be trusting any content in those directories.
# artd doesn't need to access /data/local/tmp, but it needs to access
# /data/{user,user_de}/<user-id>/com.android.shell/... for compiling secondary
# dex files.
neverallow {
domain
-adbd
-artd
-dumpstate
-installd
-init
-shell
-vold
} shell_data_file:dir no_w_dir_perms;
neverallow {
domain
-adbd
-appdomain
-artd
-dumpstate
-init
-installd
-simpleperf_app_runner
-system_server # why?
userdebug_or_eng(`-uncrypt')
} shell_data_file:dir open;
neverallow {
domain
-adbd
-appdomain
-artd
-dumpstate
-init
-installd
-simpleperf_app_runner
-system_server # why?
userdebug_or_eng(`-aconfigd')
userdebug_or_eng(`-uncrypt')
userdebug_or_eng(`-virtualizationmanager')
userdebug_or_eng(`-crosvm')
} shell_data_file:dir search;
# respect system_app sandboxes
neverallow {
domain
-appdomain
-artd # compile secondary dex files
-system_server #populate com.android.providers.settings/databases/settings.db.
-installd # creation of app sandbox
-traced_probes # resolve inodes for i/o tracing.
# only needs open and read, the rest is neverallow in
# traced_probes.te.
} system_app_data_file:dir_file_class_set { create unlink open };
neverallow {
isolated_app_all
ephemeral_app
priv_app
sdk_sandbox_all
untrusted_app_all
} system_app_data_file:dir_file_class_set { create unlink open };
neverallow { domain -init } mtectrl:process { dyntransition transition };
neverallow { domain -init } kcmdlinectrl:process { dyntransition transition };
# For now, don't allow processes other than gmscore to access /data/misc_ce/<userid>/checkin
neverallow { domain -gmscore_app -init -vold_prepare_subdirs } checkin_data_file:{dir file} *;
# Do not allow write access to aconfig flag value files except init and aconfigd
neverallow { domain -init -aconfigd -system_server } aconfig_storage_metadata_file:dir no_w_dir_perms;
neverallow { domain -init -aconfigd -system_server } aconfig_storage_metadata_file:file no_w_file_perms;
neverallow { domain -dexopt_chroot_setup -init } proc:{ file dir } mounton;
neverallow { domain -dexopt_chroot_setup -init -zygote } proc_type:{ file dir } mounton;
# Only init/vendor are allowed to write sysfs_pgsize_migration;
# ueventd needs write access to all sysfs files.
neverallow { domain -init -vendor_init -ueventd } sysfs_pgsize_migration:file no_w_file_perms;
# We need to be able to rely on vsock labels, so disallow changing them.
neverallow domain *:vsock_socket { relabelfrom relabelto };