diff mbox series

[2/2] selftests/sgx: Add SGX selftest augment_via_eaccept_long

Message ID 20220815233900.11225-2-jarkko@kernel.org
State New
Headers show
Series None | expand

Commit Message

Jarkko Sakkinen Aug. 15, 2022, 11:39 p.m. UTC
From: Vijay Dhanraj <vijay.dhanraj@intel.com>

Add a new test case which is same as augment_via_eaccept but adds a
larger number of EPC pages to stress test EAUG via EACCEPT.

Signed-off-by: Vijay Dhanraj <vijay.dhanraj@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
I removed Githubisms (hyphens), added missing subsystem tag, and
cleaned up the commit message a bit.
 tools/testing/selftests/sgx/load.c      |   5 +-
 tools/testing/selftests/sgx/main.c      | 120 +++++++++++++++++++++++-
 tools/testing/selftests/sgx/main.h      |   3 +-
 tools/testing/selftests/sgx/sigstruct.c |   2 +-
 4 files changed, 125 insertions(+), 5 deletions(-)

Comments

Jarkko Sakkinen Aug. 25, 2022, 1:28 a.m. UTC | #1
On Wed, Aug 17, 2022 at 03:39:36PM +0000, Dhanraj, Vijay wrote:
> 
> 
> > -----Original Message-----
> > From: Jarkko Sakkinen <jarkko@kernel.org>
> > Sent: Wednesday, August 17, 2022 7:39 AM
> > To: Dhanraj, Vijay <vijay.dhanraj@intel.com>
> > Cc: Chatre, Reinette <reinette.chatre@intel.com>; Dave Hansen
> > <dave.hansen@linux.intel.com>; linux-sgx@vger.kernel.org; Shuah Khan
> > <shuah@kernel.org>; open list:KERNEL SELFTEST FRAMEWORK <linux-
> > kselftest@vger.kernel.org>; open list <linux-kernel@vger.kernel.org>
> > Subject: Re: [PATCH 2/2] selftests/sgx: Add SGX selftest
> > augment_via_eaccept_long
> > 
> > On Wed, Aug 17, 2022 at 01:27:38AM +0000, Dhanraj, Vijay wrote:
> > > I think changing it to "int i" will cause a buffer overflow with
> > > edmm_size being 8GB.
> > 
> > Hmm.. 'i' iterates segments. Amd I missing something?
> > 
> > BR, Jarkko
> 
> It is also used when iterating over pages to eaccept. This might cause an issue.
> 
> 	for (i = 0; i < edmm_size; i += 4096) {
> 		eaccept_op.epc_addr = (uint64_t)(addr + i);
> 
> Regards, Vijay

Ah got it, thanks.

BR, Jarkko
diff mbox series

Patch

diff --git a/tools/testing/selftests/sgx/load.c b/tools/testing/selftests/sgx/load.c
index 94bdeac1cf04..7de1b15c90b1 100644
--- a/tools/testing/selftests/sgx/load.c
+++ b/tools/testing/selftests/sgx/load.c
@@ -171,7 +171,8 @@  uint64_t encl_get_entry(struct encl *encl, const char *symbol)
 	return 0;
 }
 
-bool encl_load(const char *path, struct encl *encl, unsigned long heap_size)
+bool encl_load(const char *path, struct encl *encl, unsigned long heap_size,
+			   unsigned long edmm_size)
 {
 	const char device_path[] = "/dev/sgx_enclave";
 	struct encl_segment *seg;
@@ -300,7 +301,7 @@  bool encl_load(const char *path, struct encl *encl, unsigned long heap_size)
 
 	encl->src_size = encl->segment_tbl[j].offset + encl->segment_tbl[j].size;
 
-	for (encl->encl_size = 4096; encl->encl_size < encl->src_size; )
+	for (encl->encl_size = 4096; encl->encl_size < encl->src_size + edmm_size;)
 		encl->encl_size <<= 1;
 
 	return true;
diff --git a/tools/testing/selftests/sgx/main.c b/tools/testing/selftests/sgx/main.c
index 9820b3809c69..65e79682f75e 100644
--- a/tools/testing/selftests/sgx/main.c
+++ b/tools/testing/selftests/sgx/main.c
@@ -25,6 +25,8 @@  static const uint64_t MAGIC = 0x1122334455667788ULL;
 static const uint64_t MAGIC2 = 0x8877665544332211ULL;
 vdso_sgx_enter_enclave_t vdso_sgx_enter_enclave;
 
+static const unsigned long edmm_size = 8589934592; //8G
+
 /*
  * Security Information (SECINFO) data structure needed by a few SGX
  * instructions (eg. ENCLU[EACCEPT] and ENCLU[EMODPE]) holds meta-data
@@ -183,7 +185,7 @@  static bool setup_test_encl(unsigned long heap_size, struct encl *encl,
 	unsigned int i;
 	void *addr;
 
-	if (!encl_load("test_encl.elf", encl, heap_size)) {
+	if (!encl_load("test_encl.elf", encl, heap_size, edmm_size)) {
 		encl_delete(encl);
 		TH_LOG("Failed to load the test enclave.");
 		return false;
@@ -1210,6 +1212,122 @@  TEST_F(enclave, augment_via_eaccept)
 	munmap(addr, PAGE_SIZE);
 }
 
+/*
+ * Test for the addition of large number of pages to an initialized enclave via
+ * a pre-emptive run of EACCEPT on page to be added.
+ */
+#define TIMEOUT_LONG 900 /* seconds */
+TEST_F_TIMEOUT(enclave, augment_via_eaccept_long, TIMEOUT_LONG)
+{
+	struct encl_op_get_from_addr get_addr_op;
+	struct encl_op_put_to_addr put_addr_op;
+	struct encl_op_eaccept eaccept_op;
+	size_t total_size = 0;
+	void *addr;
+	unsigned long i;
+
+	if (!sgx2_supported())
+		SKIP(return, "SGX2 not supported");
+
+	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;
+
+	for (i = 0; i < self->encl.nr_segments; i++) {
+		struct encl_segment *seg = &self->encl.segment_tbl[i];
+
+		total_size += seg->size;
+		TH_LOG("test enclave: total_size = %ld, seg->size = %ld", total_size, seg->size);
+	}
+
+	/*
+	 * Actual enclave size is expected to be larger than the loaded
+	 * test enclave since enclave size must be a power of 2 in bytes while
+	 * test_encl does not consume it all.
+	 */
+	EXPECT_LT(total_size + edmm_size, self->encl.encl_size);
+
+	/*
+	 * mmap() a page at end of existing enclave to be used for dynamic
+	 * EPC page.
+	 *
+	 * Kernel will allow new mapping using any permissions if it
+	 * falls into the enclave's address range but not backed
+	 * by existing enclave pages.
+	 */
+	TH_LOG("mmaping pages at end of enclave...");
+	addr = mmap((void *)self->encl.encl_base + total_size, edmm_size,
+			PROT_READ | PROT_WRITE | PROT_EXEC, MAP_SHARED | MAP_FIXED,
+			self->encl.fd, 0);
+	EXPECT_NE(addr, MAP_FAILED);
+
+	self->run.exception_vector = 0;
+	self->run.exception_error_code = 0;
+	self->run.exception_addr = 0;
+
+	/*
+	 * Run EACCEPT on new page to trigger the #PF->EAUG->EACCEPT(again
+	 * without a #PF). All should be transparent to userspace.
+	 */
+	TH_LOG("Entering enclave to run EACCEPT for each page of %zd bytes may take a while ...",
+			edmm_size);
+	eaccept_op.flags = SGX_SECINFO_R | SGX_SECINFO_W | SGX_SECINFO_REG | SGX_SECINFO_PENDING;
+	eaccept_op.ret = 0;
+	eaccept_op.header.type = ENCL_OP_EACCEPT;
+
+	for (i = 0; i < edmm_size; i += 4096) {
+		eaccept_op.epc_addr = (uint64_t)(addr + i);
+
+		EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);
+		if (self->run.exception_vector == 14 &&
+			self->run.exception_error_code == 4 &&
+			self->run.exception_addr == self->encl.encl_base) {
+			munmap(addr, edmm_size);
+			SKIP(return, "Kernel does not support adding pages to initialized enclave");
+		}
+
+		EXPECT_EQ(self->run.exception_vector, 0);
+		EXPECT_EQ(self->run.exception_error_code, 0);
+		EXPECT_EQ(self->run.exception_addr, 0);
+		ASSERT_EQ(eaccept_op.ret, 0);
+		ASSERT_EQ(self->run.function, EEXIT);
+	}
+
+	/*
+	 * New page should be accessible from within enclave - attempt to
+	 * write to it.
+	 */
+	put_addr_op.value = MAGIC;
+	put_addr_op.addr = (unsigned long)addr;
+	put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;
+
+	EXPECT_EQ(ENCL_CALL(&put_addr_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);
+
+	/*
+	 * Read memory from newly added page that was just written to,
+	 * confirming that data previously written (MAGIC) is present.
+	 */
+	get_addr_op.value = 0;
+	get_addr_op.addr = (unsigned long)addr;
+	get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;
+
+	EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);
+
+	EXPECT_EQ(get_addr_op.value, MAGIC);
+	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);
+
+	munmap(addr, edmm_size);
+}
+
 /*
  * SGX2 page type modification test in two phases:
  * Phase 1:
diff --git a/tools/testing/selftests/sgx/main.h b/tools/testing/selftests/sgx/main.h
index fc585be97e2f..fe5d39ac0e1e 100644
--- a/tools/testing/selftests/sgx/main.h
+++ b/tools/testing/selftests/sgx/main.h
@@ -35,7 +35,8 @@  extern unsigned char sign_key[];
 extern unsigned char sign_key_end[];
 
 void encl_delete(struct encl *ctx);
-bool encl_load(const char *path, struct encl *encl, unsigned long heap_size);
+bool encl_load(const char *path, struct encl *encl, unsigned long heap_size,
+			   unsigned long edmm_size);
 bool encl_measure(struct encl *encl);
 bool encl_build(struct encl *encl);
 uint64_t encl_get_entry(struct encl *encl, const char *symbol);
diff --git a/tools/testing/selftests/sgx/sigstruct.c b/tools/testing/selftests/sgx/sigstruct.c
index 50c5ab1aa6fa..6000cf0e4975 100644
--- a/tools/testing/selftests/sgx/sigstruct.c
+++ b/tools/testing/selftests/sgx/sigstruct.c
@@ -343,7 +343,7 @@  bool encl_measure(struct encl *encl)
 	if (!ctx)
 		goto err;
 
-	if (!mrenclave_ecreate(ctx, encl->src_size))
+	if (!mrenclave_ecreate(ctx, encl->encl_size))
 		goto err;
 
 	for (i = 0; i < encl->nr_segments; i++) {