[PATCH V2 15/15] selftests/sgx: Add test for multiple TCS entry

From: Reinette Chatre
Date: Thu Oct 28 2021 - 16:38:18 EST


Each thread executing in an enclave is associated with a Thread Control
Structure (TCS). The SGX test enclave contains two hardcoded TCS, thus
supporting two threads in the enclave.

Add a test to ensure it is possible to enter enclave at both entrypoints.

Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
Acked-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
Changes since V1:
- Add Jarkko and Dave's signatures.

tools/testing/selftests/sgx/defines.h | 1 +
tools/testing/selftests/sgx/main.c | 32 +++++++++++++++++++++++++
tools/testing/selftests/sgx/test_encl.c | 6 +++++
3 files changed, 39 insertions(+)

diff --git a/tools/testing/selftests/sgx/defines.h b/tools/testing/selftests/sgx/defines.h
index 0bbda6f0c7d3..02d775789ea7 100644
--- a/tools/testing/selftests/sgx/defines.h
+++ b/tools/testing/selftests/sgx/defines.h
@@ -23,6 +23,7 @@ enum encl_op_type {
ENCL_OP_GET_FROM_BUFFER,
ENCL_OP_PUT_TO_ADDRESS,
ENCL_OP_GET_FROM_ADDRESS,
+ ENCL_OP_NOP,
ENCL_OP_MAX,
};

diff --git a/tools/testing/selftests/sgx/main.c b/tools/testing/selftests/sgx/main.c
index 9efb619e0393..a86796d70a7b 100644
--- a/tools/testing/selftests/sgx/main.c
+++ b/tools/testing/selftests/sgx/main.c
@@ -448,6 +448,38 @@ TEST_F(enclave, clobbered_vdso_and_user_function)
EXPECT_EQ(self->run.user_data, 0);
}

+/*
+ * Sanity check that it is possible to enter either of the two hardcoded TCS
+ */
+TEST_F(enclave, tcs_entry)
+{
+ struct encl_op_header op;
+
+ ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));
+
+ memset(&self->run, 0, sizeof(self->run));
+ self->run.tcs = self->encl.encl_base;
+
+ op.type = ENCL_OP_NOP;
+
+ EXPECT_EQ(ENCL_CALL(&op, &self->run, true), 0);
+
+ EXPECT_EEXIT(&self->run);
+ EXPECT_EQ(self->run.exception_vector, 0);
+ EXPECT_EQ(self->run.exception_error_code, 0);
+ EXPECT_EQ(self->run.exception_addr, 0);
+
+ /* Move to the next TCS. */
+ self->run.tcs = self->encl.encl_base + PAGE_SIZE;
+
+ EXPECT_EQ(ENCL_CALL(&op, &self->run, true), 0);
+
+ EXPECT_EEXIT(&self->run);
+ EXPECT_EQ(self->run.exception_vector, 0);
+ EXPECT_EQ(self->run.exception_error_code, 0);
+ EXPECT_EQ(self->run.exception_addr, 0);
+}
+
/*
* Second page of .data segment is used to test changing PTE permissions.
* This spans the local encl_buffer within the test enclave.
diff --git a/tools/testing/selftests/sgx/test_encl.c b/tools/testing/selftests/sgx/test_encl.c
index 5d86e3e6456a..4fca01cfd898 100644
--- a/tools/testing/selftests/sgx/test_encl.c
+++ b/tools/testing/selftests/sgx/test_encl.c
@@ -49,6 +49,11 @@ static void do_encl_op_get_from_addr(void *_op)
memcpy(&op->value, (void *)op->addr, 8);
}

+static void do_encl_op_nop(void *_op)
+{
+
+}
+
void encl_body(void *rdi, void *rsi)
{
const void (*encl_op_array[ENCL_OP_MAX])(void *) = {
@@ -56,6 +61,7 @@ void encl_body(void *rdi, void *rsi)
do_encl_op_get_from_buf,
do_encl_op_put_to_addr,
do_encl_op_get_from_addr,
+ do_encl_op_nop,
};

struct encl_op_header *op = (struct encl_op_header *)rdi;
--
2.25.1