Commit 0710a1a7 authored by Mickaël Salaün's avatar Mickaël Salaün Committed by David S. Miller
Browse files

selftests/harness: Merge TEST_F_FORK() into TEST_F() 



Replace Landlock-specific TEST_F_FORK() with an improved TEST_F() which
brings four related changes:

Run TEST_F()'s tests in a grandchild process to make it possible to
drop privileges and delegate teardown to the parent.

Compared to TEST_F_FORK(), simplify handling of the test grandchild
process thanks to vfork(2), and makes it generic (e.g. no explicit
conversion between exit code and _metadata).

Compared to TEST_F_FORK(), run teardown even when tests failed with an
assert thanks to commit 63e6b2a4 ("selftests/harness: Run TEARDOWN
for ASSERT failures").

Simplify the test harness code by removing the no_print and step fields
which are not used.  I added this feature just after I made
kselftest_harness.h more broadly available but this step counter
remained even though it wasn't needed after all. See commit 369130b6
("selftests: Enhance kselftest_harness.h to print which assert failed").

Replace spaces with tabs in one line of __TEST_F_IMPL().

Cc: Günther Noack <gnoack@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Will Drewry <wad@chromium.org>
Signed-off-by: default avatarMickaël Salaün <mic@digikod.net>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e7404865

tools/testing/selftests/kselftest_harness.h

+25 −31
Original line number Diff line number Diff line
@@ -95,14 +95,6 @@ 
 * E.g., #define TH_LOG_ENABLED 1

 *

 * If no definition is provided, logging is enabled by default.

 *

 * If there is no way to print an error message for the process running the

 * test (e.g. not allowed to write to stderr), it is still possible to get the

 * ASSERT_* number for which the test failed.  This behavior can be enabled by

 * writing `_metadata->no_print = true;` before the check sequence that is

 * unable to print.  When an error occur, instead of printing an error message

 * and calling `abort(3)`, the test process call `_exit(2)` with the assert

 * number as argument, which is then printed by the parent process.

 */

#define TH_LOG(fmt, ...) do { \

	if (TH_LOG_ENABLED) \
@@ -363,6 +355,11 @@ 
 * Defines a test that depends on a fixture (e.g., is part of a test case).

 * Very similar to TEST() except that *self* is the setup instance of fixture's

 * datatype exposed for use by the implementation.

 *

 * The @test_name code is run in a separate process sharing the same memory

 * (i.e. vfork), which means that the test process can update its privileges

 * without impacting the related FIXTURE_TEARDOWN() (e.g. to remove files from

 * a directory where write access was dropped).

 */

#define TEST_F(fixture_name, test_name) \

	__TEST_F_IMPL(fixture_name, test_name, -1, TEST_TIMEOUT_DEFAULT)
@@ -384,6 +381,7 @@ 
	{ \

		/* fixture data is alloced, setup, and torn down per call. */ \

		FIXTURE_DATA(fixture_name) self; \

		pid_t child = 1; \

		memset(&self, 0, sizeof(FIXTURE_DATA(fixture_name))); \

		if (setjmp(_metadata->env) == 0) { \

			fixture_name##_setup(_metadata, &self, variant->data); \
@@ -391,8 +389,20 @@ 
			if (!_metadata->passed || _metadata->skip) \

				return; \

			_metadata->setup_completed = true; \

			/* Use the same _metadata. */ \

			child = vfork(); \

			if (child == 0) { \

				fixture_name##_##test_name(_metadata, &self, variant->data); \

				_exit(0); \

			} \

			if (child < 0) { \

				ksft_print_msg("ERROR SPAWNING TEST GRANDCHILD\n"); \

				_metadata->passed = 0; \

			} \

		} \

		if (child == 0) \

			/* Child failed and updated the shared _metadata. */ \

			_exit(0); \

		if (_metadata->setup_completed) \

			fixture_name##_teardown(_metadata, &self, variant->data); \

		__test_check_assert(_metadata); \
@@ -694,18 +704,12 @@ 
	for (; _metadata->trigger; _metadata->trigger = \

			__bail(_assert, _metadata))



#define __INC_STEP(_metadata) \

	/* Keep "step" below 255 (which is used for "SKIP" reporting). */	\

	if (_metadata->passed && _metadata->step < 253) \

		_metadata->step++;



#define is_signed_type(var)       (!!(((__typeof__(var))(-1)) < (__typeof__(var))1))



#define __EXPECT(_expected, _expected_str, _seen, _seen_str, _t, _assert) do { \

	/* Avoid multiple evaluation of the cases */ \

	__typeof__(_expected) __exp = (_expected); \

	__typeof__(_seen) __seen = (_seen); \

	if (_assert) __INC_STEP(_metadata); \

	if (!(__exp _t __seen)) { \

		/* Report with actual signedness to avoid weird output. */ \

		switch (is_signed_type(__exp) * 2 + is_signed_type(__seen)) { \
@@ -751,7 +755,6 @@ 
#define __EXPECT_STR(_expected, _seen, _t, _assert) do { \

	const char *__exp = (_expected); \

	const char *__seen = (_seen); \

	if (_assert) __INC_STEP(_metadata); \

	if (!(strcmp(__exp, __seen) _t 0))  { \

		__TH_LOG("Expected '%s' %s '%s'.", __exp, #_t, __seen); \

		_metadata->passed = 0; \
@@ -837,8 +840,6 @@ struct __test_metadata { 
	int trigger; /* extra handler after the evaluation */

	int timeout;	/* seconds to wait for test timeout */

	bool timed_out;	/* did this test timeout instead of exiting? */

	__u8 step;

	bool no_print; /* manual trigger when TH_LOG_STREAM is not available */

	bool aborted;	/* stopped test due to failed ASSERT */

	bool setup_completed; /* did setup finish? */

	jmp_buf env;	/* for exiting out of test early */
@@ -873,12 +874,9 @@ static inline int __bail(int for_realz, struct __test_metadata *t) 


static inline void __test_check_assert(struct __test_metadata *t)

{

	if (t->aborted) {

		if (t->no_print)

			_exit(t->step);

	if (t->aborted)

		abort();

}

}



struct __test_metadata *__active_test;

static void __timeout_handler(int sig, siginfo_t *info, void *ucontext)
@@ -954,13 +952,12 @@ void __wait_for_test(struct __test_metadata *t) 
			case 0:

				t->passed = 1;

				break;

			/* Other failure, assume step report. */

			/* Failure */

			default:

				t->passed = 0;

				fprintf(TH_LOG_STREAM,

					"# %s: Test failed at step #%d\n",

					t->name,

					WEXITSTATUS(status));

					"# %s: Test failed\n",

					t->name);

			}

		}

	} else if (WIFSIGNALED(status)) {
@@ -1114,8 +1111,6 @@ void __run_test(struct __fixture_metadata *f, 
	t->passed = 1;

	t->skip = 0;

	t->trigger = 0;

	t->step = 1;

	t->no_print = 0;

	memset(t->results->reason, 0, sizeof(t->results->reason));



	ksft_print_msg(" RUN           %s%s%s.%s ...\n",
@@ -1137,8 +1132,7 @@ void __run_test(struct __fixture_metadata *f, 
		/* Pass is exit 0 */

		if (t->passed)

			_exit(0);

		/* Something else happened, report the step. */

		_exit(t->step);

		_exit(1);

	} else {

		__wait_for_test(t);

	}

tools/testing/selftests/landlock/common.h

+2 −60
Original line number Diff line number Diff line
@@ -23,66 +23,8 @@ 
#define __maybe_unused __attribute__((__unused__))

#endif



/*

 * TEST_F_FORK() is useful when a test drop privileges but the corresponding

 * FIXTURE_TEARDOWN() requires them (e.g. to remove files from a directory

 * where write actions are denied).  For convenience, FIXTURE_TEARDOWN() is

 * also called when the test failed, but not when FIXTURE_SETUP() failed.  For

 * this to be possible, we must not call abort() but instead exit smoothly

 * (hence the step print).

 */

/* clang-format off */

#define TEST_F_FORK(fixture_name, test_name) \

	static void fixture_name##_##test_name##_child( \

		struct __test_metadata *_metadata, \

		FIXTURE_DATA(fixture_name) *self, \

		const FIXTURE_VARIANT(fixture_name) *variant); \

	__TEST_F_IMPL(fixture_name, test_name, -1, TEST_TIMEOUT_DEFAULT) \

	{ \

		int status; \

		const pid_t child = fork(); \

		if (child < 0) \

			abort(); \

		if (child == 0) { \

			_metadata->no_print = 1; \

			fixture_name##_##test_name##_child(_metadata, self, variant); \

			if (_metadata->skip) \

				_exit(255); \

			if (_metadata->passed) \

				_exit(0); \

			_exit(_metadata->step); \

		} \

		if (child != waitpid(child, &status, 0)) \

			abort(); \

		if (WIFSIGNALED(status) || !WIFEXITED(status)) { \

			_metadata->passed = 0; \

			_metadata->step = 1; \

			return; \

		} \

		switch (WEXITSTATUS(status)) { \

		case 0: \

			_metadata->passed = 1; \

			break; \

		case 255: \

			_metadata->passed = 1; \

			_metadata->skip = 1; \

			break; \

		default: \

			_metadata->passed = 0; \

			_metadata->step = WEXITSTATUS(status); \

			break; \

		} \

	} \

	static void fixture_name##_##test_name##_child( \

		struct __test_metadata __attribute__((unused)) *_metadata, \

		FIXTURE_DATA(fixture_name) __attribute__((unused)) *self, \

		const FIXTURE_VARIANT(fixture_name) \

			__attribute__((unused)) *variant)

/* clang-format on */



/* Makes backporting easier. */

#undef TEST_F

#define TEST_F(fixture_name, test_name) TEST_F_FORK(fixture_name, test_name)

/* TEST_F_FORK() should not be used for new tests. */

#define TEST_F_FORK(fixture_name, test_name) TEST_F(fixture_name, test_name)



#ifndef landlock_create_ruleset

static inline int