Merge "Constrain cgroups access."

private/app_neverallows.te

@@ -274,3 +274,6 @@ neverallow all_untrusted_apps mediaextractor_update_service:service_manager find
 # This will go away in a future Android release
 neverallow { all_untrusted_apps -untrusted_app_25 } proc_tty_drivers:file r_file_perms;
 neverallow all_untrusted_apps proc_tty_drivers:file ~r_file_perms;
+
+# Untrusted apps are not allowed to use cgroups.
+neverallow all_untrusted_apps cgroup:file *;

private/priv_app.te

@@ -218,3 +218,6 @@ neverallow priv_app file_type:file link;
 # upon traceur to pass a file descriptor which they can then read
 neverallow priv_app trace_data_file:dir *;
 neverallow priv_app trace_data_file:file { no_w_file_perms open };
+
+# Do not allow priv_app access to cgroups.
+neverallow priv_app cgroup:file *;

private/system_app.te

@@ -122,6 +122,9 @@ allow system_app {
   proc_version
 }:file r_file_perms;
 
+# Settings app writes to /dev/stune/foreground/tasks.
+allow system_app cgroup:file w_file_perms;
+
 control_logd(system_app)
 read_runtime_log_tags(system_app)
 get_prop(system_app, device_logging_prop)

public/app.te

@@ -22,10 +22,6 @@ allow appdomain zygote_exec:file rx_file_perms;
 # Notify zygote of death;
 allow appdomain zygote:process sigchld;
 
-# Place process into foreground / background
-allow appdomain cgroup:dir { search write };
-allow appdomain cgroup:file rw_file_perms;
-
 # Read /data/dalvik-cache.
 allow appdomain dalvikcache_data_file:dir { search getattr };
 allow appdomain dalvikcache_data_file:file r_file_perms;

public/domain.te

@@ -258,9 +258,34 @@ allow domain selinuxfs:file getattr;
 allow domain sysfs:dir search;
 allow domain selinuxfs:filesystem getattr;
 
-# For /acct/uid/*/tasks.
-allow domain cgroup:dir { search write };
-allow domain cgroup:file w_file_perms;
+# Path resolution access in cgroups.
+allow domain cgroup:dir search;
+allow { coredomain -appdomain } cgroup:dir w_dir_perms;
+allow { coredomain -appdomain } cgroup:file w_file_perms;
+
+# TODO(b/110043362): Clean up cgroup access from app domains.
+allow {
+  # Can not use all_untrusted_apps macro here, so expanding inline.
+  # This list is essentially { appdomain -all_untrusted_apps -priv_app }
+  appdomain
+  -ephemeral_app
+  -isolated_app
+  -mediaprovider
+  -untrusted_app
+  -untrusted_app_25
+  -untrusted_app_27
+  -untrusted_app_all
+  -priv_app
+} cgroup:file w_file_perms;
+auditallow appdomain cgroup:file w_file_perms;
+
+# TODO(b/110043362): Clean up cgroup access from non-system domains.
+allow { domain -coredomain } cgroup:file w_file_perms;
+auditallow {
+  domain
+  -coredomain
+  -vendor_init
+} cgroup:file w_file_perms;
 
 # Almost all processes log tracing information to
 # /sys/kernel/debug/tracing/trace_marker

public/init.te

@@ -93,7 +93,7 @@ allow init sysfs:dir mounton;
 allow init tmpfs:dir create_dir_perms;
 allow init tmpfs:dir mounton;
 allow init cgroup:dir create_dir_perms;
-r_dir_file(init, cgroup)
+allow init cgroup:file rw_file_perms;
 allow init cpuctl_device:dir { create mounton };
 
 # /config

public/vendor_init.te

@@ -15,6 +15,7 @@ allow vendor_init rootfs:lnk_file { create unlink };
 
 # Create cgroups mount points in tmpfs and mount cgroups on them.
 allow vendor_init cgroup:dir create_dir_perms;
+allow vendor_init cgroup:file w_file_perms;
 
 # /config
 allow vendor_init configfs:dir mounton;