ueventd: add tests for setegid()/setfscreatecon() and threads
setegid() and setfscreatecon() on Android both operate on a per-thread
basis, not a per-process basis.
Ueventd may take advantage of this in the future, so this CL
introduces tests that ensure that this functionality remains
consistent.
Bug: 63441941
Test: newly added unit tests
Change-Id: I8b1c62cc322b6fe44b748550a4cea8658d9efd88
diff --git a/init/Android.bp b/init/Android.bp
index fce424e..47578ea 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -153,6 +153,7 @@
"init_test.cpp",
"property_service_test.cpp",
"service_test.cpp",
+ "ueventd_test.cpp",
"util_test.cpp",
],
shared_libs: [
diff --git a/init/ueventd_test.cpp b/init/ueventd_test.cpp
new file mode 100644
index 0000000..86d7055
--- /dev/null
+++ b/init/ueventd_test.cpp
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <linux/futex.h>
+#include <pthread.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <string>
+#include <thread>
+#include <vector>
+
+#include <android-base/file.h>
+#include <android-base/scopeguard.h>
+#include <android-base/test_utils.h>
+#include <gtest/gtest.h>
+#include <selinux/selinux.h>
+
+using namespace std::string_literals;
+
+template <typename T, typename F>
+void WriteFromMultipleThreads(std::vector<std::pair<std::string, T>>& files_and_parameters,
+ F function) {
+ auto num_threads = files_and_parameters.size();
+ pthread_barrier_t barrier;
+ pthread_barrier_init(&barrier, nullptr, num_threads);
+ auto barrier_destroy =
+ android::base::make_scope_guard([&barrier]() { pthread_barrier_destroy(&barrier); });
+
+ auto make_thread_function = [&function, &barrier](const auto& file, const auto& parameter) {
+ return [&]() {
+ function(parameter);
+ pthread_barrier_wait(&barrier);
+ android::base::WriteStringToFile("<empty>", file);
+ };
+ };
+
+ std::vector<std::thread> threads;
+ // TODO(b/63712782): Structured bindings + templated containers are broken in clang :(
+ // for (const auto& [file, parameter] : files_and_parameters) {
+ for (const auto& pair : files_and_parameters) {
+ const auto& file = pair.first;
+ const auto& parameter = pair.second;
+ threads.emplace_back(std::thread(make_thread_function(file, parameter)));
+ }
+
+ for (auto& thread : threads) {
+ thread.join();
+ }
+}
+
+TEST(ueventd, setegid_IsPerThread) {
+ if (getuid() != 0) return;
+
+ TemporaryDir dir;
+
+ gid_t gid = 0;
+ std::vector<std::pair<std::string, gid_t>> files_and_gids;
+ std::generate_n(std::back_inserter(files_and_gids), 100, [&gid, &dir]() {
+ gid++;
+ return std::pair(dir.path + "/gid_"s + std::to_string(gid), gid);
+ });
+
+ WriteFromMultipleThreads(files_and_gids, [](gid_t gid) { EXPECT_EQ(0, setegid(gid)); });
+
+ for (const auto& [file, expected_gid] : files_and_gids) {
+ struct stat info;
+ EXPECT_EQ(0, stat(file.c_str(), &info));
+ EXPECT_EQ(expected_gid, info.st_gid);
+ }
+}
+
+TEST(ueventd, setfscreatecon_IsPerThread) {
+ if (getuid() != 0) return;
+
+ const char* const contexts[] = {
+ "u:object_r:audio_device:s0",
+ "u:object_r:sensors_device:s0",
+ "u:object_r:video_device:s0"
+ "u:object_r:zero_device:s0",
+ };
+
+ TemporaryDir dir;
+ std::vector<std::pair<std::string, std::string>> files_and_contexts;
+ for (const char* context : contexts) {
+ files_and_contexts.emplace_back(dir.path + "/context_"s + context, context);
+ }
+
+ WriteFromMultipleThreads(files_and_contexts, [](const std::string& context) {
+ EXPECT_EQ(0, setfscreatecon(context.c_str()));
+ });
+
+ for (const auto& [file, expected_context] : files_and_contexts) {
+ char* file_context;
+ EXPECT_GT(getfilecon(file.c_str(), &file_context), 0);
+ EXPECT_EQ(expected_context, file_context);
+ freecon(file_context);
+ }
+}