Explain uworker unsafety in fuzz_task

src/clusterfuzz/_internal/bot/tasks/utasks/fuzz_task.py

@@ -1764,7 +1764,12 @@ def run(self):
 
     # Data bundle directories can also have testcases which are kept in-place
     # because of dependencies.
-    self.data_directory = setup.trusted_get_data_bundle_directory(self.fuzzer)
+    if self.uworker_input.setup_input.data_bundle_corpuses:
+      data_bundle = self.uworker_input.setup_input.data_bundle_corpuses[0]
+    else:
+      data_bundle = None
+    self.data_directory = setup.get_data_bundle_directory(
+        self.fuzzer, data_bundle)
     if not self.data_directory:
       logs.error(
           'Unable to setup data bundle %s.' % self.fuzzer.data_bundle_name)
@@ -1924,7 +1929,7 @@ def handle_fuzz_no_fuzz_target_selected(output):
                    output.uworker_input.uworker_env)
 
 
-def _make_session(uworker_input):
+def _make_session(uworker_input: uworker_msg_pb2.Input) -> FuzzingSession:
   test_timeout = environment.get_value('TEST_TIMEOUT')
   return FuzzingSession(
       uworker_input,

src/clusterfuzz/_internal/datastore/data_handler.py

@@ -19,6 +19,7 @@
 import re
 import shlex
 import time
+from typing import List
 
 from google.cloud import ndb
 
@@ -1600,7 +1601,8 @@ def get_testcase_variant(testcase_id, job_type):
 FUZZ_TARGET_UPDATE_FAIL_DELAY = 2
 
 
-def record_fuzz_target(engine_name, binary_name, job_type):
+def record_fuzz_target(engine_name: str, binary_name: str,
+                       job_type: str) -> data_types.FuzzTarget:
   """Records exsistence of fuzz target to the DB."""
   result = record_fuzz_targets(engine_name, [binary_name], job_type)[0]
 
@@ -1636,7 +1638,8 @@ def get_or_create_multi_entities_from_keys(mapping):
     retries=FUZZ_TARGET_UPDATE_FAIL_RETRIES,
     delay=FUZZ_TARGET_UPDATE_FAIL_DELAY,
     function='datastore.data_handler.record_fuzz_targets')
-def record_fuzz_targets(engine_name, binaries, job_type):
+def record_fuzz_targets(engine_name: str, binaries: List[str],
+                        job_type: str) -> List[data_types.FuzzTarget]:
   """Record existence of fuzz targets to the DB."""
   # TODO(metzman): All of this code assumes that fuzzing jobs are behaving
   # reasonably and won't try to DoS us by putting bogus fuzzers in the db.
@@ -1669,7 +1672,7 @@ def record_fuzz_targets(engine_name, binaries, job_type):
   jobs = get_or_create_multi_entities_from_keys(job_mapping)
 
   for job in jobs:
-    # TODO(metzman): Decide if we want to handle unused fuzzers differentlyo.
+    # TODO(metzman): Decide if we want to handle unused fuzzers differently.
     job.last_run = utils.utcnow()
 
   ndb_utils.put_multi(jobs)