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gin / v8_platform_page_allocator_unittest.cc [blame]
// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif
#include "gin/v8_platform_page_allocator.h"
#include "base/cpu.h"
#include "build/build_config.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "v8/include/v8-platform.h"
// includes for Branch Target Instruction tests
#if defined(ARCH_CPU_ARM64) && (OS_LINUX || OS_ANDROID)
// BTI is only available for AArch64, relevant platform are Android and Linux
#include "partition_alloc/arm_bti_test_functions.h"
#include "partition_alloc/page_allocator_constants.h"
#if BUILDFLAG(IS_POSIX)
#include <signal.h>
#include "testing/gtest/include/gtest/gtest-death-test.h"
#endif
#endif // defined(ARCH_CPU_ARM64) && (OS_LINUX || OS_ANDROID)
namespace gin {
TEST(V8PlatformPageAllocatorTest, VerifyGetPageConfig) {
auto page_allocator = gin::PageAllocator();
EXPECT_EQ(page_allocator.GetPageConfigPermissionsForTesting(
v8::PageAllocator::kNoAccess),
partition_alloc::PageAccessibilityConfiguration::kInaccessible);
EXPECT_EQ(page_allocator.GetPageConfigPermissionsForTesting(
v8::PageAllocator::kRead),
partition_alloc::PageAccessibilityConfiguration::kRead);
EXPECT_EQ(page_allocator.GetPageConfigPermissionsForTesting(
v8::PageAllocator::kReadWrite),
partition_alloc::PageAccessibilityConfiguration::kReadWrite);
#if defined(__ARM_FEATURE_BTI_DEFAULT)
EXPECT_EQ(
page_allocator.GetPageConfigPermissionsForTesting(
v8::PageAllocator::kReadExecute),
base::CPU::GetInstanceNoAllocation().has_bti()
? partition_alloc::PageAccessibilityConfiguration::
kReadExecuteProtected
: partition_alloc::PageAccessibilityConfiguration::kReadExecute);
EXPECT_EQ(
page_allocator.GetPageConfigPermissionsForTesting(
v8::PageAllocator::kReadWriteExecute),
base::CPU::GetInstanceNoAllocation().has_bti()
? partition_alloc::PageAccessibilityConfiguration::
kReadWriteExecuteProtected
: partition_alloc::PageAccessibilityConfiguration::kReadWriteExecute);
#else
EXPECT_EQ(page_allocator.GetPageConfigPermissionsForTesting(
v8::PageAllocator::kReadExecute),
partition_alloc::PageAccessibilityConfiguration::kReadExecute);
EXPECT_EQ(page_allocator.GetPageConfigPermissionsForTesting(
v8::PageAllocator::kReadWriteExecute),
partition_alloc::PageAccessibilityConfiguration::kReadWriteExecute);
#endif
EXPECT_EQ(page_allocator.GetPageConfigPermissionsForTesting(
v8::PageAllocator::kNoAccessWillJitLater),
partition_alloc::PageAccessibilityConfiguration::
kInaccessibleWillJitLater);
}
#if defined(ARCH_CPU_ARM64) && (OS_LINUX || OS_ANDROID)
#ifdef GTEST_HAS_DEATH_TEST
using BTITestFunction = int64_t (*)(int64_t);
using V8PlatformPageAllocatorBTIDeathTest =
::testing::TestWithParam<v8::PageAllocator::Permission>;
TEST_P(V8PlatformPageAllocatorBTIDeathTest, VerifyExecutablePagesAreProtected) {
const v8::PageAllocator::Permission permission_to_test = GetParam();
auto page_allocator = gin::PageAllocator();
auto const memory_size =
partition_alloc::internal::PageAllocationGranularity();
auto const memory_alignment =
partition_alloc::internal::PageAllocationGranularity();
// Next, map some read-write memory and copy some test helper functions there.
char* const buffer = reinterpret_cast<char*>(page_allocator.AllocatePages(
nullptr, memory_size, memory_alignment,
v8::PageAllocator::Permission::kReadWriteExecute));
ptrdiff_t const function_range =
reinterpret_cast<char*>(arm_bti_test_function_end) -
reinterpret_cast<char*>(arm_bti_test_function);
ptrdiff_t const invalid_offset =
reinterpret_cast<char*>(arm_bti_test_function_invalid_offset) -
reinterpret_cast<char*>(arm_bti_test_function);
// ensure alignment to 4 bytes required by function call convention
EXPECT_EQ(0u, ((uint64_t)buffer) % 4);
EXPECT_EQ(0u, ((uint64_t)function_range) % 4);
EXPECT_EQ(0u, ((uint64_t)invalid_offset) % 4);
memcpy(buffer, reinterpret_cast<void*>(arm_bti_test_function),
function_range);
// Next re-protect the page to the permission level to test
page_allocator.SetPermissions(buffer, memory_size, permission_to_test);
// Attempt to call a function with BTI landing pad.
BTITestFunction const bti_enabled_fn =
reinterpret_cast<BTITestFunction>(buffer);
// bti_enabled_fn must return 18, no matter if BTI is actually enabled or not.
EXPECT_EQ(bti_enabled_fn(15), 18);
// Next, attempt to call a function without BTI landing pad.
BTITestFunction const bti_invalid_fn =
reinterpret_cast<BTITestFunction>(buffer + invalid_offset);
// Expectation for behaviour of bti_invalid_fn depends on the capabilities of
// the actual CPU we are running on. The code that were are trying to execute
// is assembly code and always has BTI enabled.
if (base::CPU::GetInstanceNoAllocation().has_bti()) {
#if BUILDFLAG(IS_POSIX) // signal handling is available on POSIX compliant
// systems only
EXPECT_EXIT({ bti_invalid_fn(15); }, testing::KilledBySignal(SIGILL),
""); // Should crash with SIGILL.
#endif // BUILDFLAG(IS_POSIX)
} else {
EXPECT_EQ(bti_invalid_fn(15), 17);
}
page_allocator.FreePages(buffer, memory_size);
}
INSTANTIATE_TEST_SUITE_P(
,
V8PlatformPageAllocatorBTIDeathTest,
testing::Values(v8::PageAllocator::Permission::kReadExecute,
v8::PageAllocator::Permission::kReadWriteExecute));
#endif // GTEST_HAS_DEATH_TEST
#endif // if defined(ARCH_CPU_ARM64) && (OS_LINUX || OS_ANDROID)
} // namespace gin