platform_system_sepolicy/public/crash_dump.te
Nick Kralevich 5e37271df8 Introduce system_file_type
system_file_type is a new attribute used to identify files which exist
on the /system partition. It's useful for allow rules in init, which are
based off of a blacklist of writable files. Additionally, it's useful
for constructing neverallow rules to prevent regressions.

Additionally, add commented out tests which enforce that all files on
the /system partition have the system_file_type attribute. These tests
will be uncommented in a future change after all the device-specific
policies are cleaned up.

Test: Device boots and no obvious problems.
Change-Id: Id9bae6625f042594c8eba74ca712abb09702c1e5
2018-09-27 12:52:09 -07:00

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2.2 KiB
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type crash_dump, domain;
type crash_dump_exec, system_file_type, exec_type, file_type;
# crash_dump might inherit CAP_SYS_PTRACE from a privileged process,
# which will result in an audit log even when it's allowed to trace.
dontaudit crash_dump self:global_capability_class_set { sys_ptrace };
userdebug_or_eng(`
allow crash_dump logd:process { ptrace signal sigchld sigstop sigkill };
# Let crash_dump write to /dev/kmsg_debug crashes that happen before logd comes up.
allow crash_dump kmsg_debug_device:chr_file { open append };
')
# Use inherited file descriptors
allow crash_dump domain:fd use;
# Read/write IPC pipes inherited from crashing processes.
allow crash_dump domain:fifo_file { read write };
# Append to pipes given to us by processes requesting dumps (e.g. dumpstate)
allow crash_dump domain:fifo_file { append };
r_dir_file(crash_dump, domain)
allow crash_dump exec_type:file r_file_perms;
# Read /data/dalvik-cache.
allow crash_dump dalvikcache_data_file:dir { search getattr };
allow crash_dump dalvikcache_data_file:file r_file_perms;
# Read APK files.
r_dir_file(crash_dump, apk_data_file);
# Read all /vendor
r_dir_file(crash_dump, { vendor_file same_process_hal_file })
# Talk to tombstoned
unix_socket_connect(crash_dump, tombstoned_crash, tombstoned)
# Talk to ActivityManager.
unix_socket_connect(crash_dump, system_ndebug, system_server)
# Append to ANR files.
allow crash_dump anr_data_file:file { append getattr };
# Append to tombstone files.
allow crash_dump tombstone_data_file:file { append getattr };
# crash_dump writes out logcat logs at the bottom of tombstones,
# which is super useful in some cases.
unix_socket_connect(crash_dump, logdr, logd)
# Crash dump is not intended to access the following data types. Since these
# are WAI, suppress the denials to clean up the logs.
dontaudit crash_dump {
core_data_file_type
vendor_file_type
}:dir search;
dontaudit crash_dump system_data_file:file read;
###
### neverallow assertions
###
# A domain transition must occur for crash_dump to get the privileges needed to trace the process.
# Do not allow the execution of crash_dump without a domain transition.
neverallow domain crash_dump_exec:file execute_no_trans;