microdroid/system/private/traced.te

# SELinux policy for the traced daemon running inside Microdroid.
# For the host Android policy check system/sepolicy/private/traced.te
# So far, this is file contains a subset of rules defined for the host Android.

type traced, domain, coredomain;
type traced_exec, system_file_type, exec_type, file_type;
type traced_tmpfs, file_type;

# Allow init to exec traced daemon
init_daemon_domain(traced)

# Required for perfetto_produced macro
tmpfs_domain(traced)

# Allow to pass a file descriptor for the output trace from "perfetto" (the
# cmdline client) and other shell binaries to traced and let traced write
# directly into that (rather than returning the trace contents over the socket).
allow traced perfetto:fd use;
allow traced shell:fd use;
allow traced shell:fifo_file { read write };

# Allow the service to create new files within /data/misc/perfetto-traces.
allow traced perfetto_traces_data_file:file create_file_perms;
allow traced perfetto_traces_data_file:dir rw_dir_perms;

# Allow traced to use shared memory supplied by producers. Typically, traced
# (i.e. the tracing service) creates the shared memory used for data transfer
# from the producer. This rule allows an alternative scheme, where the producer
# creates the shared memory, that is then adopted by traced (after validating
# that it is appropriately sealed).
# This list has to replicate the tmpfs domains of all applicable domains that
# have perfetto_producer() macro applied to them.
# perfetto_tmpfs excluded as it should never need to use the producer-supplied
# shared memory scheme.
allow traced traced_probes_tmpfs:file { getattr map read write };


###
### Neverallow rules
###
### traced should NEVER do any of this

# Block device access.
neverallow traced dev_type:blk_file { read write };

# ptrace any other process
neverallow traced domain:process ptrace;

# Disallows access to /data files, still allowing to write to file descriptors
# passed through the socket.
neverallow traced {
  data_file_type
  -perfetto_traces_data_file
  # We need following 3 lines because allow rules for them are defined at the
  # domain/coredomain level.
  -system_data_file
  -system_data_root_file
  -vendor_data_file
}:dir *;

neverallow traced system_data_file:dir ~{ getattr search };
neverallow traced {
  data_file_type
  -perfetto_traces_data_file
}:file ~write;

# Only init is allowed to enter the traced domain via exec()
neverallow { domain -init } traced:process transition;
neverallow * traced:process dyntransition;