1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
9 #include <sys/resource.h>
14 #include "base/file_util.h"
15 #include "base/posix/eintr_wrapper.h"
16 #include "base/third_party/valgrind/valgrind.h"
17 #include "build/build_config.h"
18 #include "sandbox/linux/tests/unit_tests.h"
21 std::string TestFailedMessage(const std::string& msg) {
22 return msg.empty() ? std::string() : "Actual test failure: " + msg;
25 int GetSubProcessTimeoutTimeInSeconds() {
26 // 10s ought to be enough for anybody.
30 // Returns the number of threads of the current process or -1.
32 struct stat task_stat;
33 int task_d = stat("/proc/self/task", &task_stat);
34 // task_stat.st_nlink should be the number of tasks + 2 (accounting for
36 if (task_d != 0 || task_stat.st_nlink < 3)
38 const int num_threads = task_stat.st_nlink - 2;
46 extern bool kAllowForkWithThreads;
49 #if defined(OS_ANDROID)
56 bool IsArchitectureArm() {
57 #if defined(ARCH_CPU_ARM_FAMILY)
64 // TODO(jln): figure out why base/.../dynamic_annotations.h's
65 // RunningOnValgrind() cannot link.
66 bool IsRunningOnValgrind() { return RUNNING_ON_VALGRIND; }
68 static const int kExpectedValue = 42;
69 static const int kIgnoreThisTest = 43;
70 static const int kExitWithAssertionFailure = 1;
71 static const int kExitForTimeout = 2;
73 static void SigAlrmHandler(int) {
74 const char failure_message[] = "Timeout reached!\n";
75 // Make sure that we never block here.
76 if (!fcntl(2, F_SETFL, O_NONBLOCK)) {
77 ignore_result(write(2, failure_message, sizeof(failure_message) - 1));
79 _exit(kExitForTimeout);
82 // Set a timeout with a handler that will automatically fail the
84 static void SetProcessTimeout(int time_in_seconds) {
85 struct sigaction act = {};
86 act.sa_handler = SigAlrmHandler;
87 SANDBOX_ASSERT(sigemptyset(&act.sa_mask) == 0);
90 struct sigaction old_act;
91 SANDBOX_ASSERT(sigaction(SIGALRM, &act, &old_act) == 0);
93 // We don't implemenet signal chaining, so make sure that nothing else
94 // is expecting to handle SIGALRM.
95 SANDBOX_ASSERT((old_act.sa_flags & SA_SIGINFO) == 0);
96 SANDBOX_ASSERT(old_act.sa_handler == SIG_DFL);
98 SANDBOX_ASSERT(sigemptyset(&sigalrm_set) == 0);
99 SANDBOX_ASSERT(sigaddset(&sigalrm_set, SIGALRM) == 0);
100 SANDBOX_ASSERT(sigprocmask(SIG_UNBLOCK, &sigalrm_set, NULL) == 0);
101 SANDBOX_ASSERT(alarm(time_in_seconds) == 0); // There should be no previous
105 // Runs a test in a sub-process. This is necessary for most of the code
106 // in the BPF sandbox, as it potentially makes global state changes and as
107 // it also tends to raise fatal errors, if the code has been used in an
109 void UnitTests::RunTestInProcess(SandboxTestRunner* test_runner,
111 const void* death_aux) {
113 // We need to fork(), so we can't be multi-threaded, as threads could hold
115 int num_threads = CountThreads();
116 #if !defined(THREAD_SANITIZER)
117 const int kNumExpectedThreads = 1;
119 // Under TSAN, there is a special helper thread. It should be completely
120 // invisible to our testing, so we ignore it. It should be ok to fork()
121 // with this thread. It's currently buggy, but it's the best we can do until
122 // there is a way to delay the start of the thread
123 // (https://code.google.com/p/thread-sanitizer/issues/detail?id=19).
124 const int kNumExpectedThreads = 2;
127 // The kernel is at liberty to wake a thread id futex before updating /proc.
128 // If another test running in the same process has stopped a thread, it may
129 // appear as still running in /proc.
130 // We poll /proc, with an exponential back-off. At most, we'll sleep around
131 // 2^iterations nanoseconds in nanosleep().
132 if (!kAllowForkWithThreads) {
133 for (unsigned int iteration = 0; iteration < 30; iteration++) {
134 struct timespec ts = {0, 1L << iteration /* nanoseconds */};
135 PCHECK(0 == HANDLE_EINTR(nanosleep(&ts, &ts)));
136 num_threads = CountThreads();
137 if (kNumExpectedThreads == num_threads)
142 const std::string multiple_threads_error =
143 "Running sandbox tests with multiple threads "
144 "is not supported and will make the tests flaky.";
145 if (!kAllowForkWithThreads) {
146 ASSERT_EQ(kNumExpectedThreads, num_threads) << multiple_threads_error;
148 if (kNumExpectedThreads != num_threads)
149 LOG(ERROR) << multiple_threads_error;
153 ASSERT_EQ(0, pipe(fds));
154 // Check that our pipe is not on one of the standard file descriptor.
155 SANDBOX_ASSERT(fds[0] > 2 && fds[1] > 2);
158 ASSERT_LE(0, (pid = fork()));
161 // Redirect stderr to our pipe. This way, we can capture all error
162 // messages, if we decide we want to do so in our tests.
163 SANDBOX_ASSERT(dup2(fds[1], 2) == 2);
164 SANDBOX_ASSERT(!close(fds[0]));
165 SANDBOX_ASSERT(!close(fds[1]));
167 // Don't set a timeout if running on Valgrind, since it's generally much
169 if (!IsRunningOnValgrind()) {
170 SetProcessTimeout(GetSubProcessTimeoutTimeInSeconds());
173 // Disable core files. They are not very useful for our individual test
175 struct rlimit no_core = {0};
176 setrlimit(RLIMIT_CORE, &no_core);
179 _exit(kExpectedValue);
183 std::vector<char> msg_buf;
186 // Make sure read() will never block as we'll use poll() to
187 // block with a timeout instead.
188 const int fcntl_ret = fcntl(fds[0], F_SETFL, O_NONBLOCK);
189 ASSERT_EQ(0, fcntl_ret);
190 struct pollfd poll_fd = {fds[0], POLLIN | POLLRDHUP, 0};
193 // We prefer the SIGALRM timeout to trigger in the child than this timeout
194 // so we double the common value here.
195 int poll_timeout = GetSubProcessTimeoutTimeInSeconds() * 2 * 1000;
196 while ((poll_ret = poll(&poll_fd, 1, poll_timeout) > 0)) {
197 const size_t kCapacity = 256;
198 const size_t len = msg_buf.size();
199 msg_buf.resize(len + kCapacity);
200 rc = HANDLE_EINTR(read(fds[0], &msg_buf[len], kCapacity));
201 msg_buf.resize(len + std::max(rc, static_cast<ssize_t>(0)));
205 ASSERT_NE(poll_ret, -1) << "poll() failed";
206 ASSERT_NE(poll_ret, 0) << "Timeout while reading child state";
208 std::string msg(msg_buf.begin(), msg_buf.end());
211 int waitpid_returned = HANDLE_EINTR(waitpid(pid, &status, 0));
212 ASSERT_EQ(pid, waitpid_returned) << TestFailedMessage(msg);
214 // At run-time, we sometimes decide that a test shouldn't actually
215 // run (e.g. when testing sandbox features on a kernel that doesn't
216 // have sandboxing support). When that happens, don't attempt to
217 // call the "death" function, as it might be looking for a
218 // death-test condition that would never have triggered.
219 if (!WIFEXITED(status) || WEXITSTATUS(status) != kIgnoreThisTest ||
221 // We use gtest's ASSERT_XXX() macros instead of the DeathCheck
222 // functions. This means, on failure, "return" is called. This
223 // only works correctly, if the call of the "death" callback is
224 // the very last thing in our function.
225 death(status, msg, death_aux);
229 void UnitTests::DeathSuccess(int status, const std::string& msg, const void*) {
230 std::string details(TestFailedMessage(msg));
232 bool subprocess_terminated_normally = WIFEXITED(status);
233 ASSERT_TRUE(subprocess_terminated_normally) << details;
234 int subprocess_exit_status = WEXITSTATUS(status);
235 ASSERT_EQ(kExpectedValue, subprocess_exit_status) << details;
236 bool subprocess_exited_but_printed_messages = !msg.empty();
237 EXPECT_FALSE(subprocess_exited_but_printed_messages) << details;
240 void UnitTests::DeathSuccessAllowNoise(int status,
241 const std::string& msg,
243 std::string details(TestFailedMessage(msg));
245 bool subprocess_terminated_normally = WIFEXITED(status);
246 ASSERT_TRUE(subprocess_terminated_normally) << details;
247 int subprocess_exit_status = WEXITSTATUS(status);
248 ASSERT_EQ(kExpectedValue, subprocess_exit_status) << details;
251 void UnitTests::DeathMessage(int status,
252 const std::string& msg,
254 std::string details(TestFailedMessage(msg));
255 const char* expected_msg = static_cast<const char*>(aux);
257 bool subprocess_terminated_normally = WIFEXITED(status);
258 ASSERT_TRUE(subprocess_terminated_normally) << details;
259 int subprocess_exit_status = WEXITSTATUS(status);
260 ASSERT_EQ(kExitWithAssertionFailure, subprocess_exit_status) << details;
261 bool subprocess_exited_without_matching_message =
262 msg.find(expected_msg) == std::string::npos;
263 EXPECT_FALSE(subprocess_exited_without_matching_message) << details;
266 void UnitTests::DeathExitCode(int status,
267 const std::string& msg,
269 int expected_exit_code = static_cast<int>(reinterpret_cast<intptr_t>(aux));
270 std::string details(TestFailedMessage(msg));
272 bool subprocess_terminated_normally = WIFEXITED(status);
273 ASSERT_TRUE(subprocess_terminated_normally) << details;
274 int subprocess_exit_status = WEXITSTATUS(status);
275 ASSERT_EQ(expected_exit_code, subprocess_exit_status) << details;
278 void UnitTests::DeathBySignal(int status,
279 const std::string& msg,
281 int expected_signo = static_cast<int>(reinterpret_cast<intptr_t>(aux));
282 std::string details(TestFailedMessage(msg));
284 bool subprocess_terminated_by_signal = WIFSIGNALED(status);
285 ASSERT_TRUE(subprocess_terminated_by_signal) << details;
286 int subprocess_signal_number = WTERMSIG(status);
287 ASSERT_EQ(expected_signo, subprocess_signal_number) << details;
290 void UnitTests::AssertionFailure(const char* expr, const char* file, int line) {
291 fprintf(stderr, "%s:%d:%s", file, line, expr);
293 _exit(kExitWithAssertionFailure);
296 void UnitTests::IgnoreThisTest() {
298 _exit(kIgnoreThisTest);