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// Copyright 2017 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/allocation.h"
#if V8_OS_POSIX
#include <setjmp.h>
#include <signal.h>
#include <unistd.h> // NOLINT
#endif // V8_OS_POSIX
#include "testing/gtest/include/gtest/gtest.h"
namespace v8 {
namespace internal {
// TODO(eholk): Add a windows version of permissions tests.
#if V8_OS_POSIX
namespace {
// These tests make sure the routines to allocate memory do so with the correct
// permissions.
//
// Unfortunately, there is no API to find the protection of a memory address,
// so instead we test permissions by installing a signal handler, probing a
// memory location and recovering from the fault.
//
// We don't test the execution permission because to do so we'd have to
// dynamically generate code and test if we can execute it.
class MemoryAllocationPermissionsTest : public ::testing::Test {
static void SignalHandler(int signal, siginfo_t* info, void*) {
siglongjmp(continuation_, 1);
}
struct sigaction old_action_;
// On Mac, sometimes we get SIGBUS instead of SIGSEGV.
#if V8_OS_MACOSX
struct sigaction old_bus_action_;
#endif
protected:
virtual void SetUp() {
struct sigaction action;
action.sa_sigaction = SignalHandler;
sigemptyset(&action.sa_mask);
action.sa_flags = SA_SIGINFO;
sigaction(SIGSEGV, &action, &old_action_);
#if V8_OS_MACOSX
sigaction(SIGBUS, &action, &old_bus_action_);
#endif
}
virtual void TearDown() {
// Be a good citizen and restore the old signal handler.
sigaction(SIGSEGV, &old_action_, nullptr);
#if V8_OS_MACOSX
sigaction(SIGBUS, &old_bus_action_, nullptr);
#endif
}
public:
static sigjmp_buf continuation_;
enum class MemoryAction { kRead, kWrite };
void ProbeMemory(volatile int* buffer, MemoryAction action,
bool should_succeed) {
const int save_sigs = 1;
if (!sigsetjmp(continuation_, save_sigs)) {
switch (action) {
case MemoryAction::kRead: {
// static_cast to remove the reference and force a memory read.
USE(static_cast<int>(*buffer));
break;
}
case MemoryAction::kWrite: {
*buffer = 0;
break;
}
}
if (should_succeed) {
SUCCEED();
} else {
FAIL();
}
return;
}
if (should_succeed) {
FAIL();
} else {
SUCCEED();
}
}
void TestPermissions(PageAllocator::Permission permission, bool can_read,
bool can_write) {
const size_t page_size = AllocatePageSize();
int* buffer = static_cast<int*>(
AllocatePages(nullptr, page_size, page_size, permission));
ProbeMemory(buffer, MemoryAction::kRead, can_read);
ProbeMemory(buffer, MemoryAction::kWrite, can_write);
CHECK(FreePages(buffer, page_size));
}
};
sigjmp_buf MemoryAllocationPermissionsTest::continuation_;
} // namespace
TEST_F(MemoryAllocationPermissionsTest, DoTest) {
TestPermissions(PageAllocator::Permission::kNoAccess, false, false);
TestPermissions(PageAllocator::Permission::kRead, true, false);
TestPermissions(PageAllocator::Permission::kReadWrite, true, true);
TestPermissions(PageAllocator::Permission::kReadWriteExecute, true, true);
TestPermissions(PageAllocator::Permission::kReadExecute, true, false);
}
#endif // V8_OS_POSIX
// Basic tests of allocation.
class AllocationTest : public ::testing::Test {};
TEST(AllocationTest, AllocateAndFree) {
size_t page_size = v8::internal::AllocatePageSize();
CHECK_NE(0, page_size);
// A large allocation, aligned at native allocation granularity.
const size_t kAllocationSize = 1 * v8::internal::MB;
void* mem_addr = v8::internal::AllocatePages(
v8::internal::GetRandomMmapAddr(), kAllocationSize, page_size,
PageAllocator::Permission::kReadWrite);
CHECK_NOT_NULL(mem_addr);
CHECK(v8::internal::FreePages(mem_addr, kAllocationSize));
// A large allocation, aligned significantly beyond native granularity.
const size_t kBigAlignment = 64 * v8::internal::MB;
void* aligned_mem_addr = v8::internal::AllocatePages(
AlignedAddress(v8::internal::GetRandomMmapAddr(), kBigAlignment),
kAllocationSize, kBigAlignment, PageAllocator::Permission::kReadWrite);
CHECK_NOT_NULL(aligned_mem_addr);
CHECK_EQ(aligned_mem_addr, AlignedAddress(aligned_mem_addr, kBigAlignment));
CHECK(v8::internal::FreePages(aligned_mem_addr, kAllocationSize));
}
TEST(AllocationTest, ReserveMemory) {
size_t page_size = v8::internal::AllocatePageSize();
const size_t kAllocationSize = 1 * v8::internal::MB;
void* mem_addr = v8::internal::AllocatePages(
v8::internal::GetRandomMmapAddr(), kAllocationSize, page_size,
PageAllocator::Permission::kReadWrite);
CHECK_NE(0, page_size);
CHECK_NOT_NULL(mem_addr);
size_t commit_size = v8::internal::CommitPageSize();
CHECK(v8::internal::SetPermissions(mem_addr, commit_size,
PageAllocator::Permission::kReadWrite));
// Check whether we can write to memory.
int* addr = static_cast<int*>(mem_addr);
addr[v8::internal::KB - 1] = 2;
CHECK(v8::internal::SetPermissions(mem_addr, commit_size,
PageAllocator::Permission::kNoAccess));
CHECK(v8::internal::FreePages(mem_addr, kAllocationSize));
}
} // namespace internal
} // namespace v8
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