A mechanism to identify/forbid/"rewrite" non-temporal instructions (and other)

src/trusted/validator/validation_pnacl_mode_test.cc

+/*
+   2  * Copyright (c) 2015 The Native Client Authors. All rights reserved.
+   3  * Use of this source code is governed by a BSD-style license that can be
+   4  * found in the LICENSE file.
+   5  */

[Petr Hosek, 2015/07/20 23:58:57]

Please remove the line numbers.

[ruiq, 2015/07/21 02:52:24]

Done.

+
+#include "gtest/gtest.h"
+
+#include "native_client/src/shared/platform/nacl_log.h"
+#include "native_client/src/shared/utils/types.h"
+#include "native_client/src/trusted/validator/ncvalidate.h"
+
+#define CODE_SIZE 32
+#define NOP 0x90
+
+
+class ValidationPnaclModeTests : public ::testing::Test {

[Petr Hosek, 2015/07/20 23:58:57]

Nit: Please use PNaCl, not Pnacl.

[ruiq, 2015/07/21 02:52:24]

Done.

+  protected:
+    NaClValidationMetadata *metadata_ptr;
+    const struct NaClValidatorInterface *validator;
+    NaClCPUFeatures *cpu_features;
+
+    unsigned char code_buffer[CODE_SIZE];
+
+    void SetUp() {
+      metadata_ptr = NULL;
+      validator = NaClCreateValidator();
+      cpu_features = (NaClCPUFeatures *) malloc(validator->CPUFeatureSize);
+      EXPECT_NE(cpu_features, (NaClCPUFeatures *) NULL);
+      memset(cpu_features, 0, validator->CPUFeatureSize);
+      validator->SetAllCPUFeatures(cpu_features);
+
+      memset(code_buffer, NOP, sizeof(code_buffer));
+    }
+
+    NaClValidationStatus Validate(int pnacl_mode) {
+      return validator->Validate(0, code_buffer, 32,
+          FALSE,  /* stubout_mode */
+          pnacl_mode,
+          FALSE,  /* readonly_test */
+          cpu_features,
+          metadata_ptr,
+          NULL);
+    }
+
+    void TearDown() {
+      free(cpu_features);
+    }
+};
+
+// mov %edi,%edi; movnti %rax,0x68(%r15,%rdi,1)
+const char* movnti_code = "\x89\xff\x49\x0f\xc3\x44\x3f\x68";
+
+TEST_F(ValidationPnaclModeTests, movnti_non_pnacl_mode) {
+  memcpy(code_buffer, movnti_code, 8);
+  NaClValidationStatus status = Validate(0);
+  // In non-pnacl mode: use the original validation rule, i.e., allow
+  // non-temporal writes. In future, we will do rewriting.
+  EXPECT_EQ(NaClValidationSucceeded, status);
+  // Code should not change.
+  EXPECT_EQ(0, memcmp(code_buffer, movnti_code, 8));
+}
+
+TEST_F(ValidationPnaclModeTests, movnti_pnacl_mode) {
+  memcpy(code_buffer, movnti_code, 8);
+  NaClValidationStatus status = Validate(1);
+  // In pnacl mode: forbid non-temporal writes.
+  EXPECT_EQ(NaClValidationFailed, status);
+  // Code should not change.
+  EXPECT_EQ(0, memcmp(code_buffer, movnti_code, 8));
+}
+
+int main(int argc, char *argv[]) {
+  // The IllegalInst test touches the log mutex deep inside the validator.
+  // This causes an SEH exception to be thrown on Windows if the mutex is not
+  // initialized.
+  // http://code.google.com/p/nativeclient/issues/detail?id=1696
+  NaClLogModuleInit();
+  testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}