[PATCH v1] selftests: Enhance kselftest_harness.h to print which assert failed
From: MickaÃl SalaÃn
Date: Sun Aug 06 2017 - 19:24:34 EST
When a test process is not able to write to TH_LOG_STREAM, this step
mechanism enable to print the assert number which triggered the failure.
This can be enabled by setting _metadata->no_print to true at the
beginning of the test sequence.
Update the seccomp-bpf test to return 0 if a test succeeded.
This feature is needed for the Landlock tests.
Signed-off-by: MickaÃl SalaÃn <mic@xxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Will Drewry <wad@xxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/CAGXu5j+D-FP8Kt9unNOqKrQJP4DYTpmgkJxWykZyrYiVPz3Y3Q@xxxxxxxxxxxxxx
---
Changes since the patch from the Landlock series:
* add the step counter in assert/expect macros and use _metadata to
enable the counter (suggested by Kees Cook)
* only count asserts
* add documentation
---
tools/testing/selftests/kselftest_harness.h | 39 +++++++++++++++++++++++----
tools/testing/selftests/seccomp/seccomp_bpf.c | 2 +-
2 files changed, 35 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index c56f72e07cd7..e81bd28bdd89 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -51,6 +51,9 @@
#define __KSELFTEST_HARNESS_H
#define _GNU_SOURCE
+#include <asm/types.h>
+#include <errno.h>
+#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
@@ -84,6 +87,14 @@
* 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) \
@@ -555,12 +566,18 @@
* return while still providing an optional block to the API consumer.
*/
#define OPTIONAL_HANDLER(_assert) \
- for (; _metadata->trigger; _metadata->trigger = __bail(_assert))
+ for (; _metadata->trigger; _metadata->trigger = \
+ __bail(_assert, _metadata->no_print, _metadata->step))
+
+#define __INC_STEP(_metadata) \
+ if (_metadata->passed && _metadata->step < 255) \
+ _metadata->step++;
#define __EXPECT(_expected, _seen, _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)) { \
unsigned long long __exp_print = (uintptr_t)__exp; \
unsigned long long __seen_print = (uintptr_t)__seen; \
@@ -576,6 +593,7 @@
#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; \
@@ -590,6 +608,8 @@ struct __test_metadata {
int termsig;
int passed;
int trigger; /* extra handler after the evaluation */
+ __u8 step;
+ bool no_print; /* manual trigger when TH_LOG_STREAM is not available */
struct __test_metadata *prev, *next;
};
@@ -634,10 +654,13 @@ static inline void __register_test(struct __test_metadata *t)
}
}
-static inline int __bail(int for_realz)
+static inline int __bail(int for_realz, bool no_print, __u8 step)
{
- if (for_realz)
+ if (for_realz) {
+ if (no_print)
+ _exit(step);
abort();
+ }
return 0;
}
@@ -655,18 +678,24 @@ void __run_test(struct __test_metadata *t)
t->passed = 0;
} else if (child_pid == 0) {
t->fn(t);
- _exit(t->passed);
+ /* return the step that failed or 0 */
+ _exit(t->passed ? 0 : t->step);
} else {
/* TODO(wad) add timeout support. */
waitpid(child_pid, &status, 0);
if (WIFEXITED(status)) {
- t->passed = t->termsig == -1 ? WEXITSTATUS(status) : 0;
+ t->passed = t->termsig == -1 ? !WEXITSTATUS(status) : 0;
if (t->termsig != -1) {
fprintf(TH_LOG_STREAM,
"%s: Test exited normally "
"instead of by signal (code: %d)\n",
t->name,
WEXITSTATUS(status));
+ } else if (!t->passed) {
+ fprintf(TH_LOG_STREAM,
+ "%s: Test failed at step #%d\n",
+ t->name,
+ WEXITSTATUS(status));
}
} else if (WIFSIGNALED(status)) {
t->passed = 0;
diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 73f5ea6778ce..4d6f92a9df6b 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -107,7 +107,7 @@ TEST(mode_strict_support)
ASSERT_EQ(0, ret) {
TH_LOG("Kernel does not support CONFIG_SECCOMP");
}
- syscall(__NR_exit, 1);
+ syscall(__NR_exit, 0);
}
TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL)
--
2.13.3