Allow dumpstate to snapshot traces and attach them to bug reports
Feature description: if a background trace is happening at the
time dumpstate is invoked, the tracing daemon will snapshot
the trace into a fixed path (/data/misc/perfetto-traces/bugreport/).
Dumpstate will attach the trace, if present, to the bugreport.
From a SELinux viewpoint this involves the following permissions:
- Allow dumpstate to exec+trans perfetto --save-for-bugreport
(this will just send an IPC to traced, which will save the trace).
- Allow dumpstate to list, read and unlink the trace file.
- Create a dedicated label for bugreport traces, to prevent that
dumpstate gets access to other traces not meant for bug reporting.
Note that this does NOT allow dumpstate to serialze arbitary traces.
Traces must be marked as "eligible for bugreport" upfront in the
trace config (which is not under dumpstate control), by
setting bugreport_score > 0.
Design doc: go/perfetto-betterbug
Bug: 170334305
Test: manual:
1. start a perfetto trace with bugreport_score > 0
2. adb shell dumpstate
3. check that the bugreport zip contains the trace
Change-Id: I259c3ee9d5be08d6b22c796b32875d7de703a230
diff --git a/private/traced.te b/private/traced.te
index 2410d7e..fcbe46d 100644
--- a/private/traced.te
+++ b/private/traced.te
@@ -28,6 +28,9 @@
# 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;
+# ... and /data/misc/perfetto-traces/bugreport*
+allow traced perfetto_traces_bugreport_data_file:file create_file_perms;
+allow traced perfetto_traces_bugreport_data_file:dir rw_dir_perms;
# Allow traceur to pass open file descriptors to traced, so traced can directly
# write into the output file without doing roundtrips over IPC.
@@ -82,6 +85,7 @@
neverallow traced {
data_file_type
-perfetto_traces_data_file
+ -perfetto_traces_bugreport_data_file
-system_data_file
-system_data_root_file
# TODO(b/72998741) Remove vendor_data_file exemption. Further restricted in a
@@ -97,6 +101,7 @@
data_file_type
-zoneinfo_data_file
-perfetto_traces_data_file
+ -perfetto_traces_bugreport_data_file
-trace_data_file
with_native_coverage(`-method_trace_data_file')
}:file ~write;