[PATCH v3 7/7] kunit: Add tests for fault

From: Mickaël Salaün
Date: Tue Mar 19 2024 - 06:55:19 EST


Add a test case to check NULL pointer dereference and make sure it would
result as a failed test.

The full kunit_fault test suite is marked as skipped when run on UML
because it would result to a kernel panic.

Tested with:
/tools/testing/kunit/kunit.py run --arch x86_64 kunit_fault
/tools/testing/kunit/kunit.py run --arch arm64 \
--cross_compile=aarch64-linux-gnu- kunit_fault

Cc: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
Cc: Rae Moar <rmoar@xxxxxxxxxx>
Cc: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: David Gow <davidgow@xxxxxxxxxx>
Signed-off-by: Mickaël Salaün <mic@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240319104857.70783-8-mic@xxxxxxxxxxx
---

Changes since v2:
* Add David's Reviewed-by.

Changes since v1:
* Remove the rodata and const test cases for now.
* Replace CONFIG_X86 check with !CONFIG_UML, and remove the "_x86"
references.
---
lib/kunit/kunit-test.c | 45 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 44 insertions(+), 1 deletion(-)

diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c
index f7980ef236a3..0fdca5fffaec 100644
--- a/lib/kunit/kunit-test.c
+++ b/lib/kunit/kunit-test.c
@@ -109,6 +109,48 @@ static struct kunit_suite kunit_try_catch_test_suite = {
.test_cases = kunit_try_catch_test_cases,
};

+#ifndef CONFIG_UML
+
+static void kunit_test_null_dereference(void *data)
+{
+ struct kunit *test = data;
+ int *null = NULL;
+
+ *null = 0;
+
+ KUNIT_FAIL(test, "This line should never be reached\n");
+}
+
+static void kunit_test_fault_null_dereference(struct kunit *test)
+{
+ struct kunit_try_catch_test_context *ctx = test->priv;
+ struct kunit_try_catch *try_catch = ctx->try_catch;
+
+ kunit_try_catch_init(try_catch,
+ test,
+ kunit_test_null_dereference,
+ kunit_test_catch);
+ kunit_try_catch_run(try_catch, test);
+
+ KUNIT_EXPECT_EQ(test, try_catch->try_result, -EINTR);
+ KUNIT_EXPECT_TRUE(test, ctx->function_called);
+}
+
+#endif /* !CONFIG_UML */
+
+static struct kunit_case kunit_fault_test_cases[] = {
+#ifndef CONFIG_UML
+ KUNIT_CASE(kunit_test_fault_null_dereference),
+#endif /* !CONFIG_UML */
+ {}
+};
+
+static struct kunit_suite kunit_fault_test_suite = {
+ .name = "kunit_fault",
+ .init = kunit_try_catch_test_init,
+ .test_cases = kunit_fault_test_cases,
+};
+
/*
* Context for testing test managed resources
* is_resource_initialized is used to test arbitrary resources
@@ -826,6 +868,7 @@ static struct kunit_suite kunit_current_test_suite = {

kunit_test_suites(&kunit_try_catch_test_suite, &kunit_resource_test_suite,
&kunit_log_test_suite, &kunit_status_test_suite,
- &kunit_current_test_suite, &kunit_device_test_suite);
+ &kunit_current_test_suite, &kunit_device_test_suite,
+ &kunit_fault_test_suite);

MODULE_LICENSE("GPL v2");
--
2.44.0