1 /*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "src/tracing/ipc/posix_shared_memory.h"
18
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <stdio.h>
22 #include <string.h>
23 #include <sys/stat.h>
24 #include <unistd.h>
25
26 #include "perfetto/base/build_config.h"
27 #include "perfetto/ext/base/file_utils.h"
28 #include "perfetto/ext/base/scoped_file.h"
29 #include "perfetto/ext/base/temp_file.h"
30 #include "perfetto/ext/base/utils.h"
31 #include "src/base/test/test_task_runner.h"
32 #include "src/base/test/vm_test_utils.h"
33 #include "src/tracing/ipc/memfd.h"
34 #include "test/gtest_and_gmock.h"
35
36 namespace perfetto {
37 namespace {
38
IsFileDescriptorClosed(int fd)39 bool IsFileDescriptorClosed(int fd) {
40 return lseek(fd, 0, SEEK_CUR) == -1 && errno == EBADF;
41 }
42
TEST(PosixSharedMemoryTest,DestructorUnmapsMemory)43 TEST(PosixSharedMemoryTest, DestructorUnmapsMemory) {
44 PosixSharedMemory::Factory factory;
45 std::unique_ptr<SharedMemory> shm =
46 factory.CreateSharedMemory(base::kPageSize);
47 ASSERT_NE(shm.get(), nullptr);
48 void* const shm_start = shm->start();
49 const size_t shm_size = shm->size();
50 ASSERT_NE(nullptr, shm_start);
51 ASSERT_EQ(base::kPageSize, shm_size);
52
53 memcpy(shm_start, "test", 5);
54 ASSERT_TRUE(base::vm_test_utils::IsMapped(shm_start, shm_size));
55
56 shm.reset();
57 ASSERT_FALSE(base::vm_test_utils::IsMapped(shm_start, shm_size));
58 }
59
TEST(PosixSharedMemoryTest,DestructorClosesFD)60 TEST(PosixSharedMemoryTest, DestructorClosesFD) {
61 std::unique_ptr<PosixSharedMemory> shm =
62 PosixSharedMemory::Create(base::kPageSize);
63 ASSERT_NE(shm.get(), nullptr);
64 int fd = shm->fd();
65 ASSERT_GE(fd, 0);
66 ASSERT_EQ(static_cast<off_t>(base::kPageSize), lseek(fd, 0, SEEK_END));
67
68 shm.reset();
69 ASSERT_TRUE(IsFileDescriptorClosed(fd));
70 }
71
TEST(PosixSharedMemoryTest,AttachToFdWithoutSeals)72 TEST(PosixSharedMemoryTest, AttachToFdWithoutSeals) {
73 base::TempFile tmp_file = base::TempFile::CreateUnlinked();
74 const int fd_num = tmp_file.fd();
75 ASSERT_EQ(0, ftruncate(fd_num, base::kPageSize));
76 ASSERT_EQ(7, base::WriteAll(fd_num, "foobar", 7));
77
78 std::unique_ptr<PosixSharedMemory> shm = PosixSharedMemory::AttachToFd(
79 tmp_file.ReleaseFD(), /*require_seals_if_supported=*/false);
80 ASSERT_NE(shm.get(), nullptr);
81 void* const shm_start = shm->start();
82 const size_t shm_size = shm->size();
83 ASSERT_NE(nullptr, shm_start);
84 ASSERT_EQ(base::kPageSize, shm_size);
85 ASSERT_EQ(0, memcmp("foobar", shm_start, 7));
86
87 ASSERT_FALSE(IsFileDescriptorClosed(fd_num));
88
89 shm.reset();
90 ASSERT_TRUE(IsFileDescriptorClosed(fd_num));
91 ASSERT_FALSE(base::vm_test_utils::IsMapped(shm_start, shm_size));
92 }
93
TEST(PosixSharedMemoryTest,AttachToFdRequiresSeals)94 TEST(PosixSharedMemoryTest, AttachToFdRequiresSeals) {
95 base::TempFile tmp_file = base::TempFile::CreateUnlinked();
96 const int fd_num = tmp_file.fd();
97 ASSERT_EQ(0, ftruncate(fd_num, base::kPageSize));
98
99 std::unique_ptr<PosixSharedMemory> shm =
100 PosixSharedMemory::AttachToFd(tmp_file.ReleaseFD());
101
102 if (HasMemfdSupport()) {
103 EXPECT_EQ(shm.get(), nullptr);
104 } else {
105 ASSERT_NE(shm.get(), nullptr);
106 EXPECT_NE(shm->start(), nullptr);
107 }
108 }
109
TEST(PosixSharedMemoryTest,CreateAndMap)110 TEST(PosixSharedMemoryTest, CreateAndMap) {
111 std::unique_ptr<PosixSharedMemory> shm =
112 PosixSharedMemory::Create(base::kPageSize);
113 void* const shm_start = shm->start();
114 const size_t shm_size = shm->size();
115 ASSERT_NE(shm_start, nullptr);
116 ASSERT_EQ(shm_size, base::kPageSize);
117
118 memcpy(shm_start, "test", 5);
119 ASSERT_TRUE(base::vm_test_utils::IsMapped(shm_start, shm_size));
120
121 base::ScopedFile shm_fd2(dup(shm->fd()));
122 std::unique_ptr<PosixSharedMemory> shm2 =
123 PosixSharedMemory::AttachToFd(std::move(shm_fd2));
124 ASSERT_NE(shm2.get(), nullptr);
125 void* const shm2_start = shm2->start();
126 const size_t shm2_size = shm2->size();
127 ASSERT_NE(shm2_start, nullptr);
128 ASSERT_EQ(shm2_size, shm_size);
129
130 ASSERT_EQ(0, memcmp("test", shm2->start(), 5));
131 ASSERT_TRUE(base::vm_test_utils::IsMapped(shm2_start, shm2_size));
132
133 shm2.reset();
134 ASSERT_FALSE(base::vm_test_utils::IsMapped(shm2_start, shm2_size));
135 ASSERT_TRUE(base::vm_test_utils::IsMapped(shm_start, shm_size));
136
137 shm.reset();
138 ASSERT_FALSE(base::vm_test_utils::IsMapped(shm2_start, shm2_size));
139 ASSERT_FALSE(base::vm_test_utils::IsMapped(shm_start, shm_size));
140 }
141
142 } // namespace
143 } // namespace perfetto
144