[PATCH for_v23 14/16] selftests/x86/sgx: Add test of vDSO with basic exit handler

[Sean Christopherson <sean.j.christopherson@intel.com>]

Add a test to verify that nothing explodes when using an exit handler to
control the flow of the vDSO.

Suggested-by: Suggested-by: Cedric Xing <cedric.xing@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
 tools/testing/selftests/x86/sgx/main.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/tools/testing/selftests/x86/sgx/main.c b/tools/testing/selftests/x86/sgx/main.c
index 2676570493f2..ae1822b10c6f 100644
--- a/tools/testing/selftests/x86/sgx/main.c
+++ b/tools/testing/selftests/x86/sgx/main.c
@@ -329,6 +329,31 @@ static void test_vdso_no_exit_handler(struct sgx_secs *secs)
 	ASSERT_EQ(exception.leaf, ENCLU_EENTER);
 }
 
+static int basic_exit_handler(long rdi, long rsi, long rdx, int ret,
+			      long r8, long r9, void *tcs, long ursp,
+			      struct sgx_enclave_exception *e)
+{
+	ASSERT_EQ(ret, 0);
+	return 0;
+}
+
+/*
+ * Test the vDSO API, __vdso_sgx_enter_enclave(), with an exit handler.
+ */
+static void test_vdso_with_exit_handler(struct sgx_secs *secs)
+{
+	struct sgx_enclave_exception exception;
+	uint64_t result = 0;
+	long ret;
+
+	memset(&exception, 0, sizeof(exception));
+
+	ret = sgx_call((void *)&MAGIC, &result, 0, 0, 0, 0, (void *)secs->base,
+		       &exception, basic_exit_handler);
+	ASSERT_EQ(ret, 0);
+	ASSERT_EQ(result, MAGIC);
+}
+
 int main(int argc, char *argv[], char *envp[])
 {
 	struct sgx_sigstruct sigstruct;
@@ -356,6 +381,7 @@ int main(int argc, char *argv[], char *envp[])
 	encl_build(&secs, bin, bin_size, &sigstruct);
 
 	test_vdso_no_exit_handler(&secs);
+	test_vdso_with_exit_handler(&secs);
 
 	printf("All tests passed!\n");
 	exit(0);
-- 
2.22.0