blob: f570ac21c907997e53fc93e977b520b867523efc [file] [log] [blame]
# Life begins with the kernel.
type kernel, domain, mlstrustedsubject;
allow kernel self:capability sys_nice;
# Run /init before we have switched domains.
allow kernel rootfs:file execute_no_trans;
# /dev/__null__ node created by init prior to policy load.
allow kernel tmpfs:chr_file rw_file_perms;
# setcon to init domain.
allow kernel self:process setcurrent;
allow kernel init:process dyntransition;
# cgroup filesystem initialization prior to setting the cgroup root directory label.
allow kernel unlabeled:dir search;
# Mount usbfs.
allow kernel usbfs:filesystem mount;
allow kernel usbfs:dir search;
# init direct restorecon calls prior to switching to init domain
# /dev and /dev/socket
allow kernel tmpfs:dir relabelfrom;
allow kernel { device socket_device }:dir relabelto;
# /dev/__properties__
allow kernel tmpfs:file relabelfrom;
allow kernel properties_device:file relabelto;
# /sys
allow kernel sysfs:{ dir file lnk_file } relabelfrom;
allow kernel sysfs_type:{ dir file lnk_file } relabelto;
allow kernel sysfs_type:dir r_dir_perms;
# Initial setenforce by init prior to switching to init domain.
# We use dontaudit instead of allow to prevent a kernel spawned userspace
# process from turning off SELinux once enabled.
dontaudit kernel self:security setenforce;
# Write to /proc/1/oom_adj prior to switching to init domain.
allow kernel self:capability sys_resource;
# Set checkreqprot by init.rc prior to switching to init domain.
allow kernel selinuxfs:file write;
allow kernel self:security setcheckreqprot;
# MTP sync (b/15835289)
# kernel thread "loop0", used by the loop block device, for ASECs (b/17158723)
allow kernel untrusted_app:fd use;
allow kernel sdcard_type:file { read write };
# Allow the kernel to read OBB files from app directories. (b/17428116)
# Kernel thread "loop0" reads a vold supplied file descriptor.
# Fixes CTS tests:
# * android.os.storage.cts.StorageManagerTest#testMountAndUnmountObbNormal
# * android.os.storage.cts.StorageManagerTest#testMountAndUnmountTwoObbs
allow kernel vold:fd use;
allow kernel app_data_file:file read;
allow kernel asec_image_file:file read;
###
### neverallow rules
###
# The initial task starts in the kernel domain (assigned via
# initial_sid_contexts), but nothing ever transitions to it.
neverallow domain kernel:process { transition dyntransition };
# The kernel domain is never entered via an exec, nor should it
# ever execute a program outside the rootfs without changing to another domain.
# If you encounter an execute_no_trans denial on the kernel domain, then
# possible causes include:
# - The program is a kernel usermodehelper. In this case, define a domain
# for the program and domain_auto_trans() to it.
# - You failed to setcon u:r:init:s0 in your init.rc and thus your init
# program was left in the kernel domain and is now trying to execute
# some other program. Fix your init.rc file.
# - You are running an exploit which switched to the init task credentials
# and is then trying to exec a shell or other program. You lose!
neverallow kernel { file_type fs_type -rootfs }:file { entrypoint execute_no_trans };