diff --git a/libc/malloc_debug/tests/backtrace_fake.cpp b/libc/malloc_debug/tests/backtrace_fake.cpp
new file mode 100644
index 0000000..32da696
--- /dev/null
+++ b/libc/malloc_debug/tests/backtrace_fake.cpp
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdint.h>
+
+#include <deque>
+#include <vector>
+#include <utility>
+
+#include "backtrace.h"
+#include "backtrace_fake.h"
+#include "debug_log.h"
+
+static std::deque<std::vector<uintptr_t>> g_fake_backtrace;
+
+void backtrace_fake_clear_all() {
+  g_fake_backtrace.clear();
+}
+
+void backtrace_fake_add(const std::vector<uintptr_t>& ips) {
+  g_fake_backtrace.push_back(ips);
+}
+
+void backtrace_startup() {
+}
+
+void backtrace_shutdown() {
+}
+
+size_t backtrace_get(uintptr_t* frames, size_t frame_num) {
+  if (frame_num == 0 || g_fake_backtrace.size() == 0) {
+    return 0;
+  }
+
+  size_t ips_size = g_fake_backtrace[0].size();
+  size_t total_frames = (frame_num < ips_size) ? frame_num : ips_size;
+  memcpy(frames, g_fake_backtrace[0].data(), sizeof(uintptr_t) * total_frames);
+  g_fake_backtrace.pop_front();
+  return total_frames;
+}
+
+void backtrace_log(uintptr_t* frames, size_t frame_count) {
+  for (size_t i = 0; i < frame_count; i++) {
+    error_log("  #%02zd pc %p", i, reinterpret_cast<void*>(frames[i]));
+  }
+}
diff --git a/libc/malloc_debug/tests/backtrace_fake.h b/libc/malloc_debug/tests/backtrace_fake.h
new file mode 100644
index 0000000..f2aa7a0
--- /dev/null
+++ b/libc/malloc_debug/tests/backtrace_fake.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MALLOC_DEBUG_TESTS_BACKTRACE_FAKE_H
+#define MALLOC_DEBUG_TESTS_BACKTRACE_FAKE_H
+
+#include <stdint.h>
+
+#include <vector>
+
+void backtrace_fake_clear_all();
+void backtrace_fake_add(const std::vector<uintptr_t>& ips);
+
+#endif // MALLOC_DEBUG_TESTS_BACKTRACE_FAKE_H
diff --git a/libc/malloc_debug/tests/libc_fake.cpp b/libc/malloc_debug/tests/libc_fake.cpp
new file mode 100644
index 0000000..45ace4d
--- /dev/null
+++ b/libc/malloc_debug/tests/libc_fake.cpp
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+extern "C" const char* getprogname() {
+  return "malloc_testing";
+}
diff --git a/libc/malloc_debug/tests/log_fake.cpp b/libc/malloc_debug/tests/log_fake.cpp
new file mode 100644
index 0000000..7350ea0
--- /dev/null
+++ b/libc/malloc_debug/tests/log_fake.cpp
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <stdarg.h>
+
+#include <string>
+
+#include <android-base/stringprintf.h>
+#include <log/log.h>
+#include <log/logger.h>
+
+// Forward declarations.
+class Backtrace;
+struct EventTagMap;
+struct AndroidLogEntry;
+
+std::string g_fake_log_buf;
+
+std::string g_fake_log_print;
+
+void resetLogs() {
+  g_fake_log_buf = "";
+  g_fake_log_print = "";
+}
+
+std::string getFakeLogBuf() {
+  return g_fake_log_buf;
+}
+
+std::string getFakeLogPrint() {
+  return g_fake_log_print;
+}
+
+extern "C" int __libc_format_log(int priority, const char* tag, const char* format, ...) {
+  g_fake_log_print += std::to_string(priority) + ' ';
+  g_fake_log_print += tag;
+  g_fake_log_print += ' ';
+
+  va_list ap;
+  va_start(ap, format);
+  android::base::StringAppendV(&g_fake_log_print, format, ap);
+  va_end(ap);
+
+  g_fake_log_print += '\n';
+
+  return 0;
+}
+
+extern "C" int __android_log_buf_write(int bufId, int prio, const char* tag, const char* msg) {
+  g_fake_log_buf += std::to_string(bufId) + ' ' + std::to_string(prio) + ' ';
+  g_fake_log_buf += tag;
+  g_fake_log_buf += ' ';
+  g_fake_log_buf += msg;
+  return 1;
+}
+
+extern "C" int __android_log_print(int prio, const char* tag, const char* fmt, ...) {
+  g_fake_log_print += std::to_string(prio) + ' ';
+  g_fake_log_print += tag;
+  g_fake_log_print += ' ';
+
+  va_list ap;
+  va_start(ap, fmt);
+  android::base::StringAppendV(&g_fake_log_print, fmt, ap);
+  va_end(ap);
+
+  g_fake_log_print += '\n';
+
+  return 1;
+}
+
+extern "C" log_id_t android_name_to_log_id(const char*) {
+  return LOG_ID_SYSTEM;
+}
+
+extern "C" struct logger_list* android_logger_list_open(log_id_t, int, unsigned int, pid_t) {
+  errno = EACCES;
+  return nullptr;
+}
+
+extern "C" int android_logger_list_read(struct logger_list*, struct log_msg*) {
+  return 0;
+}
+
+extern "C" EventTagMap* android_openEventTagMap(const char*) {
+  return nullptr;
+}
+
+extern "C" int android_log_processBinaryLogBuffer(
+    struct logger_entry*,
+    AndroidLogEntry*, const EventTagMap*, char*, int) {
+  return 0;
+}
+
+extern "C" void android_logger_list_free(struct logger_list*) {
+}
diff --git a/libc/malloc_debug/tests/log_fake.h b/libc/malloc_debug/tests/log_fake.h
new file mode 100644
index 0000000..1ea72f8
--- /dev/null
+++ b/libc/malloc_debug/tests/log_fake.h
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MALLOC_DEBUG_TESTS_LOG_FAKE_H
+#define MALLOC_DEBUG_TESTS_LOG_FAKE_H
+
+#include <string>
+
+void resetLogs();
+std::string getFakeLogBuf();
+std::string getFakeLogPrint();
+
+#endif // MALLOC_DEBUG_TESTS_LOG_FAKE_H
diff --git a/libc/malloc_debug/tests/malloc_debug_config_tests.cpp b/libc/malloc_debug/tests/malloc_debug_config_tests.cpp
new file mode 100644
index 0000000..ad25948
--- /dev/null
+++ b/libc/malloc_debug/tests/malloc_debug_config_tests.cpp
@@ -0,0 +1,380 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <limits.h>
+
+#include <memory>
+#include <string>
+
+#include <gtest/gtest.h>
+
+#include "Config.h"
+
+#include "log_fake.h"
+
+extern "C" int property_set(const char*, const char*);
+
+class MallocDebugConfigTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    resetLogs();
+  }
+
+  void TearDown() override {
+  }
+
+  std::unique_ptr<Config> config;
+
+  bool InitConfig(const char* property_value) {
+    config.reset(new Config);
+    property_set("libc.debug.malloc.options", property_value);
+    return config->SetFromProperties();
+  }
+};
+
+std::string usage_string(
+  "6 malloc_debug malloc debug options usage:\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   front_guard[=XX]\n"
+  "6 malloc_debug     Enables a front guard on all allocations. If XX is set\n"
+  "6 malloc_debug     it sets the number of bytes in the guard. The default is\n"
+  "6 malloc_debug     32 bytes.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   rear_guard[=XX]\n"
+  "6 malloc_debug     Enables a rear guard on all allocations. If XX is set\n"
+  "6 malloc_debug     it sets the number of bytes in the guard. The default is\n"
+  "6 malloc_debug     32 bytes.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   guard[=XX]\n"
+  "6 malloc_debug     Enables both a front guard and a rear guard on all allocations.\n"
+  "6 malloc_debug     If XX is set it sets the number of bytes in both guards.\n"
+  "6 malloc_debug     The default is 32 bytes.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   backtrace[=XX]\n"
+  "6 malloc_debug     Enable capturing the backtrace at the point of allocation.\n"
+  "6 malloc_debug     If XX is set it sets the number of backtrace frames.\n"
+  "6 malloc_debug     The default is 16 frames.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   backtrace_enable_on_signal[=XX]\n"
+  "6 malloc_debug     Enable capturing the backtrace at the point of allocation.\n"
+  "6 malloc_debug     The backtrace capture is not enabled until the process\n"
+  "6 malloc_debug     receives a signal. If XX is set it sets the number of backtrace\n"
+  "6 malloc_debug     frames. The default is 16 frames.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   fill_on_alloc[=XX]\n"
+  "6 malloc_debug     On first allocation, fill with the value 0xeb.\n"
+  "6 malloc_debug     If XX is set it will only fill up to XX bytes of the\n"
+  "6 malloc_debug     allocation. The default is to fill the entire allocation.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   fill_on_free[=XX]\n"
+  "6 malloc_debug     On free, fill with the value 0xef. If XX is set it will\n"
+  "6 malloc_debug     only fill up to XX bytes of the allocation. The default is to\n"
+  "6 malloc_debug     fill the entire allocation.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   fill[=XX]\n"
+  "6 malloc_debug     On both first allocation free, fill with the value 0xeb on\n"
+  "6 malloc_debug     first allocation and the value 0xef. If XX is set, only fill\n"
+  "6 malloc_debug     up to XX bytes. The default is to fill the entire allocation.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   expand_alloc[=XX]\n"
+  "6 malloc_debug     Allocate an extra number of bytes for every allocation call.\n"
+  "6 malloc_debug     If XX is set, that is the number of bytes to expand the\n"
+  "6 malloc_debug     allocation by. The default is 16 bytes.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   free_track[=XX]\n"
+  "6 malloc_debug     When a pointer is freed, do not free the memory right away.\n"
+  "6 malloc_debug     Instead, keep XX of these allocations around and then verify\n"
+  "6 malloc_debug     that they have not been modified when the total number of freed\n"
+  "6 malloc_debug     allocations exceeds the XX amount. When the program terminates,\n"
+  "6 malloc_debug     the rest of these allocations are verified.\n"
+  "6 malloc_debug     The default is to record 100 allocations.\n"
+  "6 malloc_debug \n"
+  "6 malloc_debug   leak_track\n"
+  "6 malloc_debug     Enable the leak tracking of memory allocations.\n"
+);
+
+TEST_F(MallocDebugConfigTest, unknown_option) {
+
+  ASSERT_FALSE(InitConfig("unknown_option"));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string log_msg("6 malloc_debug malloc_testing: unknown option unknown_option\n");
+  ASSERT_STREQ((log_msg + usage_string).c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, unparseable_number) {
+  ASSERT_FALSE(InitConfig("backtrace=XXX"));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string log_msg("6 malloc_debug malloc_testing: bad value for option 'backtrace'\n");
+  ASSERT_STREQ((log_msg + usage_string).c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, illegal_value_zero) {
+  ASSERT_FALSE(InitConfig("backtrace=0"));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string log_msg("6 malloc_debug malloc_testing: bad value for option 'backtrace', value must be > 0: 0\n");
+  ASSERT_STREQ((log_msg + usage_string).c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, no_space) {
+  ASSERT_FALSE(InitConfig("backtrace=10front_guard"));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string log_msg(
+      "6 malloc_debug malloc_testing: bad value for option 'backtrace', "
+      "non space found after option: front_guard\n");
+  ASSERT_STREQ((log_msg + usage_string).c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, illegal_value_negative) {
+  ASSERT_FALSE(InitConfig("backtrace=-1"));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string log_msg("6 malloc_debug malloc_testing: bad value for option 'backtrace', value must be > 0: -1\n");
+  ASSERT_STREQ((log_msg + usage_string).c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, overflow) {
+  ASSERT_FALSE(InitConfig("backtrace=99999999999999999999"));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string log_msg(
+      "6 malloc_debug malloc_testing: bad value for option 'backtrace': "
+      "Math result not representable\n");
+  ASSERT_STREQ((log_msg + usage_string).c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, set_value_error) {
+  ASSERT_FALSE(InitConfig("leak_track=12"));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string log_msg(
+      "6 malloc_debug malloc_testing: value set for option 'leak_track' "
+      "which does not take a value\n");
+  ASSERT_STREQ((log_msg + usage_string).c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, space_before_equal) {
+  ASSERT_TRUE(InitConfig("backtrace  =10"));
+  ASSERT_EQ(BACKTRACE | TRACK_ALLOCS, config->options);
+  ASSERT_EQ(10U, config->backtrace_frames);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, space_after_equal) {
+  ASSERT_TRUE(InitConfig("backtrace=  10"));
+  ASSERT_EQ(BACKTRACE | TRACK_ALLOCS, config->options);
+  ASSERT_EQ(10U, config->backtrace_frames);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, extra_space) {
+  ASSERT_TRUE(InitConfig("   backtrace=64   "));
+  ASSERT_EQ(BACKTRACE | TRACK_ALLOCS, config->options);
+  ASSERT_EQ(64U, config->backtrace_frames);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, multiple_options) {
+  ASSERT_TRUE(InitConfig("  backtrace=64   front_guard=24"));
+  ASSERT_EQ(BACKTRACE | TRACK_ALLOCS | FRONT_GUARD, config->options);
+  ASSERT_EQ(64U, config->backtrace_frames);
+  ASSERT_EQ(24U, config->front_guard_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, front_guard) {
+  ASSERT_TRUE(InitConfig("front_guard=24"));
+  ASSERT_EQ(FRONT_GUARD, config->options);
+  ASSERT_EQ(24U, config->front_guard_bytes);
+
+  ASSERT_TRUE(InitConfig("front_guard"));
+  ASSERT_EQ(FRONT_GUARD, config->options);
+  ASSERT_EQ(32U, config->front_guard_bytes);
+
+  ASSERT_TRUE(InitConfig("front_guard=39"));
+  ASSERT_EQ(FRONT_GUARD, config->options);
+  ASSERT_EQ(40U, config->front_guard_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, rear_guard) {
+  ASSERT_TRUE(InitConfig("rear_guard=50"));
+  ASSERT_EQ(REAR_GUARD, config->options);
+  ASSERT_EQ(50U, config->rear_guard_bytes);
+
+  ASSERT_TRUE(InitConfig("rear_guard"));
+  ASSERT_EQ(REAR_GUARD, config->options);
+  ASSERT_EQ(32U, config->rear_guard_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, guard) {
+  ASSERT_TRUE(InitConfig("guard=32"));
+  ASSERT_EQ(FRONT_GUARD | REAR_GUARD, config->options);
+  ASSERT_EQ(32U, config->front_guard_bytes);
+  ASSERT_EQ(32U, config->rear_guard_bytes);
+
+  ASSERT_TRUE(InitConfig("guard"));
+  ASSERT_EQ(FRONT_GUARD | REAR_GUARD, config->options);
+  ASSERT_EQ(32U, config->front_guard_bytes);
+  ASSERT_EQ(32U, config->rear_guard_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, backtrace) {
+  ASSERT_TRUE(InitConfig("backtrace=64"));
+  ASSERT_EQ(BACKTRACE | TRACK_ALLOCS, config->options);
+  ASSERT_EQ(64U, config->backtrace_frames);
+
+  ASSERT_TRUE(InitConfig("backtrace"));
+  ASSERT_EQ(BACKTRACE | TRACK_ALLOCS, config->options);
+  ASSERT_EQ(16U, config->backtrace_frames);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, backtrace_enable_on_signal) {
+  ASSERT_TRUE(InitConfig("backtrace_enable_on_signal=64"));
+  ASSERT_EQ(BACKTRACE | TRACK_ALLOCS, config->options);
+  ASSERT_EQ(64U, config->backtrace_frames);
+
+  ASSERT_TRUE(InitConfig("backtrace_enable_on_signal"));
+  ASSERT_EQ(BACKTRACE | TRACK_ALLOCS, config->options);
+  ASSERT_EQ(16U, config->backtrace_frames);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, fill_on_alloc) {
+  ASSERT_TRUE(InitConfig("fill_on_alloc=64"));
+  ASSERT_EQ(FILL_ON_ALLOC, config->options);
+  ASSERT_EQ(64U, config->fill_on_alloc_bytes);
+
+  ASSERT_TRUE(InitConfig("fill_on_alloc"));
+  ASSERT_EQ(FILL_ON_ALLOC, config->options);
+  ASSERT_EQ(SIZE_MAX, config->fill_on_alloc_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, fill_on_free) {
+  ASSERT_TRUE(InitConfig("fill_on_free=64"));
+  ASSERT_EQ(FILL_ON_FREE, config->options);
+  ASSERT_EQ(64U, config->fill_on_free_bytes);
+
+  ASSERT_TRUE(InitConfig("fill_on_free"));
+  ASSERT_EQ(FILL_ON_FREE, config->options);
+  ASSERT_EQ(SIZE_MAX, config->fill_on_free_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, fill) {
+  ASSERT_TRUE(InitConfig("fill=64"));
+  ASSERT_EQ(FILL_ON_ALLOC | FILL_ON_FREE, config->options);
+  ASSERT_EQ(64U, config->fill_on_alloc_bytes);
+  ASSERT_EQ(64U, config->fill_on_free_bytes);
+
+  ASSERT_TRUE(InitConfig("fill"));
+  ASSERT_EQ(FILL_ON_ALLOC | FILL_ON_FREE, config->options);
+  ASSERT_EQ(SIZE_MAX, config->fill_on_alloc_bytes);
+  ASSERT_EQ(SIZE_MAX, config->fill_on_free_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, expand_alloc) {
+  ASSERT_TRUE(InitConfig("expand_alloc=1234"));
+  ASSERT_EQ(EXPAND_ALLOC, config->options);
+  ASSERT_EQ(1234U, config->expand_alloc_bytes);
+
+  ASSERT_TRUE(InitConfig("expand_alloc"));
+  ASSERT_EQ(EXPAND_ALLOC, config->options);
+  ASSERT_EQ(16U, config->expand_alloc_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, free_track) {
+  ASSERT_TRUE(InitConfig("free_track=1234"));
+  ASSERT_EQ(FREE_TRACK | FILL_ON_FREE, config->options);
+  ASSERT_EQ(1234U, config->free_track_allocations);
+  ASSERT_EQ(SIZE_MAX, config->fill_on_free_bytes);
+
+  ASSERT_TRUE(InitConfig("free_track"));
+  ASSERT_EQ(FREE_TRACK | FILL_ON_FREE, config->options);
+  ASSERT_EQ(100U, config->free_track_allocations);
+  ASSERT_EQ(SIZE_MAX, config->fill_on_free_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, free_track_and_fill_on_free) {
+  ASSERT_TRUE(InitConfig("free_track=1234 fill_on_free=32"));
+  ASSERT_EQ(FREE_TRACK | FILL_ON_FREE, config->options);
+  ASSERT_EQ(1234U, config->free_track_allocations);
+  ASSERT_EQ(32U, config->fill_on_free_bytes);
+
+  ASSERT_TRUE(InitConfig("free_track fill_on_free=60"));
+  ASSERT_EQ(FREE_TRACK | FILL_ON_FREE, config->options);
+  ASSERT_EQ(100U, config->free_track_allocations);
+  ASSERT_EQ(60U, config->fill_on_free_bytes);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, leak_track) {
+  ASSERT_TRUE(InitConfig("leak_track"));
+  ASSERT_EQ(LEAK_TRACK | TRACK_ALLOCS, config->options);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugConfigTest, leak_track_fail) {
+  ASSERT_FALSE(InitConfig("leak_track=100"));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string log_msg(
+      "6 malloc_debug malloc_testing: value set for option 'leak_track' "
+      "which does not take a value\n");
+  ASSERT_STREQ((log_msg + usage_string).c_str(), getFakeLogPrint().c_str());
+}
diff --git a/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp b/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp
new file mode 100644
index 0000000..0e8ca68
--- /dev/null
+++ b/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp
@@ -0,0 +1,1391 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <malloc.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/cdefs.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <algorithm>
+#include <vector>
+#include <utility>
+
+#include <gtest/gtest.h>
+
+#include <android-base/stringprintf.h>
+
+#include <private/bionic_macros.h>
+#include <private/bionic_malloc_dispatch.h>
+
+#include "malloc_debug.h"
+
+#include "log_fake.h"
+#include "backtrace_fake.h"
+
+__BEGIN_DECLS
+
+int property_set(const char*, const char*);
+bool debug_initialize(const MallocDispatch*, int*);
+void debug_finalize();
+
+void* debug_malloc(size_t);
+void debug_free(void*);
+void* debug_calloc(size_t, size_t);
+void* debug_realloc(void*, size_t);
+int debug_posix_memalign(void**, size_t, size_t);
+void* debug_memalign(size_t, size_t);
+size_t debug_malloc_usable_size(void*);
+void debug_get_malloc_leak_info(uint8_t**, size_t*, size_t*, size_t*, size_t*);
+void debug_free_malloc_leak_info(uint8_t*);
+
+struct mallinfo debug_mallinfo();
+
+#if defined(HAVE_DEPRECATED_MALLOC_FUNCS)
+void* debug_pvalloc(size_t);
+void* debug_valloc(size_t);
+#endif
+
+__END_DECLS
+
+constexpr char DIVIDER[] =
+    "6 malloc_debug *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n";
+
+constexpr uint32_t TRACK_HEADER = 0x2;
+constexpr uint32_t BACKTRACE_HEADER = 0x4;
+
+static size_t get_tag_offset(uint32_t flags = 0, size_t backtrace_frames = 0) {
+  size_t offset = BIONIC_ALIGN(sizeof(Header), sizeof(uintptr_t));
+  if (flags & TRACK_HEADER) {
+    offset += BIONIC_ALIGN(sizeof(TrackHeader), sizeof(uintptr_t));
+  }
+  if (flags & BACKTRACE_HEADER) {
+    offset += BIONIC_ALIGN(sizeof(BacktraceHeader) + sizeof(uintptr_t) * backtrace_frames - 1, sizeof(uintptr_t));
+    offset += BIONIC_ALIGN(sizeof(BacktraceHeader) + sizeof(uintptr_t) * backtrace_frames - 1, sizeof(uintptr_t));
+  }
+  return offset;
+}
+
+class MallocDebugTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    initialized = false;
+    resetLogs();
+    backtrace_fake_clear_all();
+  }
+
+  void TearDown() override {
+    if (initialized) {
+      debug_finalize();
+    }
+  }
+
+  void Init(const char* property_value) {
+    property_set("libc.debug.malloc.options", property_value);
+    zygote = 0;
+    ASSERT_TRUE(debug_initialize(&dispatch, &zygote));
+    initialized = true;
+  }
+
+  bool initialized;
+
+  int zygote;
+
+  static MallocDispatch dispatch;
+};
+
+MallocDispatch MallocDebugTest::dispatch = {
+  .calloc = calloc,
+  .free = free,
+  .mallinfo = mallinfo,
+  .malloc = malloc,
+  .malloc_usable_size = malloc_usable_size,
+  .memalign = memalign,
+  .posix_memalign = posix_memalign,
+  .realloc = realloc,
+};
+
+void VerifyAllocCalls() {
+  size_t alloc_size = 1024;
+
+  // Verify debug_malloc.
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(alloc_size));
+  ASSERT_TRUE(pointer != nullptr);
+  for (size_t i = 0; i < debug_malloc_usable_size(pointer); i++) {
+    ASSERT_EQ(0xeb, pointer[i]);
+  }
+  debug_free(pointer);
+
+  // Verify debug_calloc.
+  pointer = reinterpret_cast<uint8_t*>(debug_calloc(1, alloc_size));
+  ASSERT_TRUE(pointer != nullptr);
+  for (size_t i = 0; i < debug_malloc_usable_size(pointer); i++) {
+    ASSERT_EQ(0, pointer[i]) << "Failed at byte " << i;
+  }
+  debug_free(pointer);
+
+  pointer = reinterpret_cast<uint8_t*>(debug_memalign(128, alloc_size));
+  ASSERT_TRUE(pointer != nullptr);
+  for (size_t i = 0; i < debug_malloc_usable_size(pointer); i++) {
+    ASSERT_EQ(0xeb, pointer[i]) << "Failed at byte " << i;
+  }
+  debug_free(pointer);
+
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(nullptr, alloc_size));
+  ASSERT_TRUE(pointer != nullptr);
+  for (size_t i = 0; i < debug_malloc_usable_size(pointer); i++) {
+    ASSERT_EQ(0xeb, pointer[i]) << "Failed at byte " << i;
+  }
+  memset(pointer, 0xff, alloc_size);
+  // Increase the size, verify the extra length is initialized to 0xeb,
+  // but the rest is 0xff.
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(pointer, alloc_size * 2));
+  ASSERT_TRUE(pointer != nullptr);
+  for (size_t i = 0; i < alloc_size; i++) {
+    ASSERT_EQ(0xff, pointer[i]) << "Failed at byte " << i;
+  }
+  for (size_t i = alloc_size; i < debug_malloc_usable_size(pointer); i++) {
+    ASSERT_EQ(0xeb, pointer[i]) << "Failed at byte " << i;
+  }
+  memset(pointer, 0xff, debug_malloc_usable_size(pointer));
+  // Shrink the size and verify nothing changes.
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(pointer, alloc_size));
+  ASSERT_TRUE(pointer != nullptr);
+  for (size_t i = 0; i < debug_malloc_usable_size(pointer); i++) {
+    ASSERT_EQ(0xff, pointer[i]) << "Failed at byte " << i;
+  }
+  // This should free the pointer.
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(pointer, 0));
+  ASSERT_TRUE(pointer == nullptr);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, fill_generic) {
+  Init("fill");
+  VerifyAllocCalls();
+}
+
+TEST_F(MallocDebugTest, fill_on_alloc_generic) {
+  Init("fill_on_alloc");
+  VerifyAllocCalls();
+}
+
+TEST_F(MallocDebugTest, fill_on_alloc_partial) {
+  Init("fill_on_alloc=25");
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  for (size_t i = 0; i < 25; i++) {
+    ASSERT_EQ(0xeb, pointer[i]) << "Failed at byte " << i;
+  }
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, fill_on_free) {
+  Init("fill_on_free free_track");
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  size_t usable_size = debug_malloc_usable_size(pointer);
+  memset(pointer, 0, usable_size);
+  debug_free(pointer);
+
+  for (size_t i = 0; i < usable_size; i++) {
+    ASSERT_EQ(0xef, pointer[i]) << "Failed at byte " << i;
+  }
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, fill_on_free_partial) {
+  Init("fill_on_free=30 free_track");
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  size_t usable_size = debug_malloc_usable_size(pointer);
+  memset(pointer, 0, usable_size);
+  debug_free(pointer);
+
+  for (size_t i = 0; i < 30; i++) {
+    ASSERT_EQ(0xef, pointer[i]) << "Failed to fill on free at byte " << i;
+  }
+  for (size_t i = 30; i < usable_size; i++) {
+    ASSERT_EQ(0, pointer[i]) << "Filled too much on byte " << i;
+  }
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, free_track_partial) {
+  Init("fill_on_free=30 free_track");
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  size_t usable_size = debug_malloc_usable_size(pointer);
+  memset(pointer, 0, usable_size);
+  debug_free(pointer);
+
+  for (size_t i = 0; i < 30; i++) {
+    ASSERT_EQ(0xef, pointer[i]) << "Failed to fill on free at byte " << i;
+  }
+  for (size_t i = 30; i < usable_size; i++) {
+    ASSERT_EQ(0, pointer[i]) << "Filled too much on byte " << i;
+  }
+
+  debug_finalize();
+  initialized = false;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, all_options) {
+  Init("guard backtrace fill expand_alloc free_track leak_track");
+  VerifyAllocCalls();
+}
+
+TEST_F(MallocDebugTest, expand_alloc) {
+  Init("expand_alloc=1024");
+
+  void* pointer = debug_malloc(10);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_LE(1034U, debug_malloc_usable_size(pointer));
+  debug_free(pointer);
+
+  pointer = debug_calloc(1, 20);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_LE(1044U, debug_malloc_usable_size(pointer));
+  debug_free(pointer);
+
+  pointer = debug_memalign(128, 15);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_LE(1039U, debug_malloc_usable_size(pointer));
+  debug_free(pointer);
+
+  pointer = debug_realloc(nullptr, 30);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_LE(1054U, debug_malloc_usable_size(pointer));
+  pointer = debug_realloc(pointer, 100);
+  ASSERT_LE(1124U, debug_malloc_usable_size(pointer));
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, front_guard) {
+  Init("front_guard=32");
+
+  // Create a buffer for doing comparisons.
+  std::vector<uint8_t> buffer(32);
+  memset(buffer.data(), 0xaa, buffer.size());
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_TRUE(memcmp(buffer.data(), &pointer[-buffer.size()], buffer.size()) == 0);
+  memset(pointer, 0xff, 100);
+  debug_free(pointer);
+
+  // Loop through a bunch alignments.
+  for (size_t alignment = 1; alignment <= 256; alignment++) {
+    pointer = reinterpret_cast<uint8_t*>(debug_memalign(alignment, 100));
+    ASSERT_TRUE(pointer != nullptr);
+    ASSERT_TRUE(memcmp(buffer.data(), &pointer[-buffer.size()], buffer.size()) == 0);
+    size_t alignment_mask = alignment - 1;
+    if (!powerof2(alignment)) {
+      alignment_mask = BIONIC_ROUND_UP_POWER_OF_2(alignment) - 1;
+    }
+    ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(pointer) & alignment_mask);
+    memset(pointer, 0xff, 100);
+    debug_free(pointer);
+  }
+
+  pointer = reinterpret_cast<uint8_t*>(debug_calloc(1, 100));
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_TRUE(memcmp(buffer.data(), &pointer[-buffer.size()], buffer.size()) == 0);
+  for (size_t i = 0; i < 100; i++) {
+    ASSERT_EQ(0, pointer[i]) << "debug_calloc non-zero byte at " << i;
+  }
+  debug_free(pointer);
+
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(nullptr, 100));
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_TRUE(memcmp(buffer.data(), &pointer[-buffer.size()], buffer.size()) == 0);
+  memset(pointer, 0xff, 100);
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(pointer, 200));
+  ASSERT_TRUE(memcmp(buffer.data(), &pointer[-buffer.size()], buffer.size()) == 0);
+  memset(pointer, 0xff, 200);
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(pointer, 0));
+  ASSERT_TRUE(pointer == nullptr);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, realloc_memalign_memory) {
+  Init("rear_guard");
+
+  void* pointer = debug_memalign(1024, 100);
+  ASSERT_TRUE(pointer != nullptr);
+  memset(pointer, 0, 100);
+
+  pointer = debug_realloc(pointer, 1024);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(1024U, debug_malloc_usable_size(pointer));
+  memset(pointer, 0, 1024);
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, front_guard_corrupted) {
+  Init("front_guard=32");
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x1, 0x2, 0x3});
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  pointer[-32] = 0x00;
+  pointer[-15] = 0x02;
+  debug_free(pointer);
+
+  std::string expected_log(DIVIDER);
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ ALLOCATION %p SIZE 100 HAS A CORRUPTED FRONT GUARD\n", pointer);
+  expected_log += "6 malloc_debug   pointer[-32] = 0x00 (expected 0xaa)\n";
+  expected_log += "6 malloc_debug   pointer[-15] = 0x02 (expected 0xaa)\n";
+  expected_log += "6 malloc_debug Backtrace at time of failure:\n";
+  expected_log += "6 malloc_debug   #00 pc 0x1\n";
+  expected_log += "6 malloc_debug   #01 pc 0x2\n";
+  expected_log += "6 malloc_debug   #02 pc 0x3\n";
+  expected_log += DIVIDER;
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, rear_guard) {
+  Init("rear_guard=32");
+
+  // Create a buffer for doing comparisons.
+  std::vector<uint8_t> buffer(32);
+  memset(buffer.data(), 0xbb, buffer.size());
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(100U, debug_malloc_usable_size(pointer));
+  ASSERT_TRUE(memcmp(buffer.data(), &pointer[100], buffer.size()) == 0);
+  memset(pointer, 0xff, 100);
+  debug_free(pointer);
+
+  // Loop through a bunch alignments.
+  for (size_t alignment = 1; alignment <= 256; alignment++) {
+    pointer = reinterpret_cast<uint8_t*>(debug_memalign(alignment, 100));
+    ASSERT_TRUE(pointer != nullptr);
+    ASSERT_EQ(100U, debug_malloc_usable_size(pointer));
+    ASSERT_TRUE(memcmp(buffer.data(), &pointer[100], buffer.size()) == 0);
+    size_t alignment_mask = alignment - 1;
+    if (!powerof2(alignment)) {
+      alignment_mask = BIONIC_ROUND_UP_POWER_OF_2(alignment) - 1;
+    }
+    ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(pointer) & alignment_mask)
+        << "Failed at alignment " << alignment << " mask " << alignment_mask;
+    memset(pointer, 0xff, 100);
+    debug_free(pointer);
+  }
+
+  pointer = reinterpret_cast<uint8_t*>(debug_calloc(1, 100));
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(100U, debug_malloc_usable_size(pointer));
+  ASSERT_TRUE(memcmp(buffer.data(), &pointer[100], buffer.size()) == 0);
+  for (size_t i = 0; i < 100; i++) {
+    ASSERT_EQ(0, pointer[i]) << "debug_calloc non-zero byte at " << i;
+  }
+  debug_free(pointer);
+
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(nullptr, 100));
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_TRUE(memcmp(buffer.data(), &pointer[100], buffer.size()) == 0);
+  memset(pointer, 0xff, 100);
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(pointer, 200));
+  ASSERT_TRUE(memcmp(buffer.data(), &pointer[200], buffer.size()) == 0);
+  for (size_t i = 0; i < 100; i++) {
+    ASSERT_EQ(0xff, pointer[i]) << "debug_realloc not copied byte at " << i;
+  }
+  memset(pointer, 0xff, 200);
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(pointer, 0));
+  ASSERT_TRUE(pointer == nullptr);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, rear_guard_corrupted) {
+  Init("rear_guard=32");
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x100, 0x200, 0x300});
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  pointer[130] = 0xbf;
+  pointer[131] = 0x00;
+  debug_free(pointer);
+
+  std::string expected_log(DIVIDER);
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ ALLOCATION %p SIZE 100 HAS A CORRUPTED REAR GUARD\n", pointer);
+  expected_log += "6 malloc_debug   pointer[130] = 0xbf (expected 0xbb)\n";
+  expected_log += "6 malloc_debug   pointer[131] = 0x00 (expected 0xbb)\n";
+  expected_log += "6 malloc_debug Backtrace at time of failure:\n";
+  expected_log += "6 malloc_debug   #00 pc 0x100\n";
+  expected_log += "6 malloc_debug   #01 pc 0x200\n";
+  expected_log += "6 malloc_debug   #02 pc 0x300\n";
+  expected_log += DIVIDER;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, rear_guard_corrupted_after_realloc_shrink) {
+  Init("rear_guard=32");
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x100, 0x200, 0x300});
+
+  void* pointer = debug_malloc(200);
+  ASSERT_TRUE(pointer != nullptr);
+  memset(pointer, 0, 200);
+
+  uint8_t* pointer_shrink = reinterpret_cast<uint8_t*>(debug_realloc(pointer, 100));
+  pointer_shrink[130] = 0xbf;
+  pointer_shrink[131] = 0x00;
+  debug_free(pointer);
+
+  // When shrinking sizes, the same pointer should be returned.
+  ASSERT_EQ(pointer, pointer_shrink);
+
+  std::string expected_log(DIVIDER);
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ ALLOCATION %p SIZE 100 HAS A CORRUPTED REAR GUARD\n", pointer);
+  expected_log += "6 malloc_debug   pointer[130] = 0xbf (expected 0xbb)\n";
+  expected_log += "6 malloc_debug   pointer[131] = 0x00 (expected 0xbb)\n";
+  expected_log += "6 malloc_debug Backtrace at time of failure:\n";
+  expected_log += "6 malloc_debug   #00 pc 0x100\n";
+  expected_log += "6 malloc_debug   #01 pc 0x200\n";
+  expected_log += "6 malloc_debug   #02 pc 0x300\n";
+  expected_log += DIVIDER;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, tag_corrupted) {
+  Init("rear_guard=32");
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xa, 0xb, 0xc});
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xaa, 0xbb, 0xcc});
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xaaa, 0xbbb, 0xccc});
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  uint8_t saved = pointer[-get_tag_offset()];
+  pointer[-get_tag_offset()] = 0x00;
+  ASSERT_EQ(0U, debug_malloc_usable_size(pointer));
+  ASSERT_TRUE(debug_realloc(pointer, 200) == nullptr);
+  debug_free(pointer);
+
+  // Fix the pointer and really free it.
+  pointer[-get_tag_offset()] = saved;
+  debug_free(pointer);
+
+  std::string expected_log(DIVIDER);
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ ALLOCATION %p HAS INVALID TAG 1ee7d000 (malloc_usable_size)\n",
+      pointer);
+  expected_log += "6 malloc_debug Backtrace at time of failure:\n";
+  expected_log += "6 malloc_debug   #00 pc 0xa\n";
+  expected_log += "6 malloc_debug   #01 pc 0xb\n";
+  expected_log += "6 malloc_debug   #02 pc 0xc\n";
+  expected_log += DIVIDER;
+
+  expected_log += DIVIDER;
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ ALLOCATION %p HAS INVALID TAG 1ee7d000 (realloc)\n",
+      pointer);
+  expected_log += "6 malloc_debug Backtrace at time of failure:\n";
+  expected_log += "6 malloc_debug   #00 pc 0xaa\n";
+  expected_log += "6 malloc_debug   #01 pc 0xbb\n";
+  expected_log += "6 malloc_debug   #02 pc 0xcc\n";
+  expected_log += DIVIDER;
+
+  expected_log += DIVIDER;
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ ALLOCATION %p HAS INVALID TAG 1ee7d000 (free)\n",
+      pointer);
+  expected_log += "6 malloc_debug Backtrace at time of failure:\n";
+  expected_log += "6 malloc_debug   #00 pc 0xaaa\n";
+  expected_log += "6 malloc_debug   #01 pc 0xbbb\n";
+  expected_log += "6 malloc_debug   #02 pc 0xccc\n";
+  expected_log += DIVIDER;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, leak_track_no_frees) {
+  Init("leak_track");
+
+  void* pointer1 = debug_malloc(200);
+  ASSERT_TRUE(pointer1 != nullptr);
+  memset(pointer1, 0, 200);
+
+  void* pointer2 = debug_malloc(128);
+  ASSERT_TRUE(pointer2 != nullptr);
+  memset(pointer2, 0, 128);
+
+  void* pointer3 = debug_malloc(1024);
+  ASSERT_TRUE(pointer3 != nullptr);
+  memset(pointer3, 0, 1024);
+
+  debug_finalize();
+  initialized = false;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string expected_log = android::base::StringPrintf(
+        "6 malloc_debug +++ malloc_testing leaked block of size 1024 at %p (leak 1 of 3)\n",
+      pointer3);
+  expected_log += android::base::StringPrintf(
+        "6 malloc_debug +++ malloc_testing leaked block of size 200 at %p (leak 2 of 3)\n",
+      pointer1);
+  expected_log += android::base::StringPrintf(
+        "6 malloc_debug +++ malloc_testing leaked block of size 128 at %p (leak 3 of 3)\n",
+      pointer2);
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, leak_track_no_frees_with_backtrace) {
+  Init("leak_track backtrace");
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x1000, 0x2000, 0x3000});
+
+  void* pointer1 = debug_malloc(100);
+  ASSERT_TRUE(pointer1 != nullptr);
+  memset(pointer1, 0, 100);
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xa000, 0xb000, 0xc000, 0xd000});
+
+  void* pointer2 = debug_malloc(128);
+  ASSERT_TRUE(pointer2 != nullptr);
+  memset(pointer2, 0, 128);
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xfe000, 0xde000, 0xce000, 0xbe000, 0xae000});
+
+  void* pointer3 = debug_malloc(1024);
+  ASSERT_TRUE(pointer3 != nullptr);
+  memset(pointer3, 0, 1024);
+
+  debug_finalize();
+  initialized = false;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string expected_log = android::base::StringPrintf(
+      "6 malloc_debug +++ malloc_testing leaked block of size 1024 at %p (leak 1 of 3)\n",
+      pointer3);
+  expected_log += "6 malloc_debug Backtrace at time of allocation:\n";
+  expected_log += "6 malloc_debug   #00 pc 0xfe000\n";
+  expected_log += "6 malloc_debug   #01 pc 0xde000\n";
+  expected_log += "6 malloc_debug   #02 pc 0xce000\n";
+  expected_log += "6 malloc_debug   #03 pc 0xbe000\n";
+  expected_log += "6 malloc_debug   #04 pc 0xae000\n";
+
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ malloc_testing leaked block of size 128 at %p (leak 2 of 3)\n",
+      pointer2);
+  expected_log += "6 malloc_debug Backtrace at time of allocation:\n";
+  expected_log += "6 malloc_debug   #00 pc 0xa000\n";
+  expected_log += "6 malloc_debug   #01 pc 0xb000\n";
+  expected_log += "6 malloc_debug   #02 pc 0xc000\n";
+  expected_log += "6 malloc_debug   #03 pc 0xd000\n";
+
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ malloc_testing leaked block of size 100 at %p (leak 3 of 3)\n",
+      pointer1);
+  expected_log += "6 malloc_debug Backtrace at time of allocation:\n";
+  expected_log += "6 malloc_debug   #00 pc 0x1000\n";
+  expected_log += "6 malloc_debug   #01 pc 0x2000\n";
+  expected_log += "6 malloc_debug   #02 pc 0x3000\n";
+
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, leak_track_frees) {
+  Init("leak_track");
+
+  void* pointer1 = debug_malloc(390);
+  ASSERT_TRUE(pointer1 != nullptr);
+  memset(pointer1, 0, 390);
+  debug_free(pointer1);
+
+  pointer1 = debug_malloc(100);
+  ASSERT_TRUE(pointer1 != nullptr);
+  memset(pointer1, 0, 100);
+
+  void* pointer2 = debug_malloc(250);
+  ASSERT_TRUE(pointer2 != nullptr);
+  memset(pointer2, 0, 250);
+  debug_free(pointer2);
+
+  pointer2 = debug_malloc(450);
+  ASSERT_TRUE(pointer2 != nullptr);
+  memset(pointer2, 0, 450);
+
+  void* pointer3 = debug_malloc(999);
+  ASSERT_TRUE(pointer3 != nullptr);
+  memset(pointer3, 0, 999);
+  debug_free(pointer2);
+
+  debug_finalize();
+  initialized = false;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string expected_log = android::base::StringPrintf(
+      "6 malloc_debug +++ malloc_testing leaked block of size 999 at %p (leak 1 of 2)\n",
+      pointer3);
+  expected_log += android::base::StringPrintf(
+      "6 malloc_debug +++ malloc_testing leaked block of size 100 at %p (leak 2 of 2)\n",
+      pointer1);
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, free_track) {
+  Init("free_track=5");
+
+  void* pointers[10];
+  for (size_t i = 0; i < sizeof(pointers) / sizeof(void*); i++) {
+    pointers[i] = debug_malloc(100 + i);
+    ASSERT_TRUE(pointers[i] != nullptr);
+    memset(pointers[i], 0, 100 + i);
+    debug_free(pointers[i]);
+  }
+
+  // Large allocations (> 4096) to verify large allocation checks.
+  void* pointer = debug_malloc(8192);
+  ASSERT_TRUE(pointer != nullptr);
+  memset(pointer, 0, 8192);
+  debug_free(pointer);
+
+  pointer = debug_malloc(9000);
+  ASSERT_TRUE(pointer != nullptr);
+  memset(pointer, 0, 9000);
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, free_track_use_after_free) {
+  Init("free_track=5");
+
+  uint8_t* pointers[5];
+  for (size_t i = 0; i < sizeof(pointers) / sizeof(void*); i++) {
+    pointers[i] = reinterpret_cast<uint8_t*>(debug_malloc(100 + i));
+    ASSERT_TRUE(pointers[i] != nullptr);
+    memset(pointers[i], 0, 100 + i);
+    debug_free(pointers[i]);
+  }
+
+  // Stomp on the data.
+  pointers[0][20] = 0xaf;
+  pointers[0][99] = 0x12;
+
+  pointers[3][3] = 0x34;
+
+  // Large allocations (> 4096) to verify large allocation checks.
+  uint8_t* pointer1_large = reinterpret_cast<uint8_t*>(debug_malloc(8192));
+  ASSERT_TRUE(pointer1_large != nullptr);
+  memset(pointer1_large, 0, 8192);
+  debug_free(pointer1_large);
+
+  pointer1_large[4095] = 0x90;
+  pointer1_large[4100] = 0x56;
+  pointer1_large[8191] = 0x89;
+
+  uint8_t* pointer2_large = reinterpret_cast<uint8_t*>(debug_malloc(9000));
+  ASSERT_TRUE(pointer2_large != nullptr);
+  memset(pointer2_large, 0, 9000);
+  debug_free(pointer2_large);
+
+  pointer2_large[8200] = 0x78;
+
+  // Do a bunch of alloc and free to verify the above frees are checked.
+  for (size_t i = 0; i < 10; i++) {
+    void* flush_pointer = debug_malloc(100+i);
+    ASSERT_TRUE(flush_pointer != nullptr);
+    memset(flush_pointer, 0, 100 + i);
+    debug_free(flush_pointer);
+  }
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string expected_log(DIVIDER);
+  expected_log += android::base::StringPrintf("6 malloc_debug +++ ALLOCATION %p USED AFTER FREE\n", pointers[0]);
+  expected_log += "6 malloc_debug   pointer[20] = 0xaf (expected 0xef)\n";
+  expected_log += "6 malloc_debug   pointer[99] = 0x12 (expected 0xef)\n";
+  expected_log += DIVIDER;
+  expected_log += DIVIDER;
+  expected_log += android::base::StringPrintf("6 malloc_debug +++ ALLOCATION %p USED AFTER FREE\n", pointers[3]);
+  expected_log += "6 malloc_debug   pointer[3] = 0x34 (expected 0xef)\n";
+  expected_log += DIVIDER;
+  expected_log += DIVIDER;
+  expected_log += android::base::StringPrintf("6 malloc_debug +++ ALLOCATION %p USED AFTER FREE\n", pointer1_large);
+  expected_log += "6 malloc_debug   pointer[4095] = 0x90 (expected 0xef)\n";
+  expected_log += "6 malloc_debug   pointer[4100] = 0x56 (expected 0xef)\n";
+  expected_log += "6 malloc_debug   pointer[8191] = 0x89 (expected 0xef)\n";
+  expected_log += DIVIDER;
+  expected_log += DIVIDER;
+  expected_log += android::base::StringPrintf("6 malloc_debug +++ ALLOCATION %p USED AFTER FREE\n", pointer2_large);
+  expected_log += "6 malloc_debug   pointer[8200] = 0x78 (expected 0xef)\n";
+  expected_log += DIVIDER;
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, free_track_use_after_free_finalize) {
+  Init("free_track=100");
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(100));
+  ASSERT_TRUE(pointer != nullptr);
+  memset(pointer, 0, 100);
+  debug_free(pointer);
+
+  pointer[56] = 0x91;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+
+  debug_finalize();
+  initialized = false;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string expected_log(DIVIDER);
+  expected_log += android::base::StringPrintf("6 malloc_debug +++ ALLOCATION %p USED AFTER FREE\n", pointer);
+  expected_log += "6 malloc_debug   pointer[56] = 0x91 (expected 0xef)\n";
+  expected_log += DIVIDER;
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, free_track_use_after_free_with_backtrace) {
+  Init("free_track=100 backtrace");
+
+  // Alloc backtrace.
+  backtrace_fake_add(std::vector<uintptr_t> {0xf0, 0xe, 0xd});
+  // Free backtrace.
+  backtrace_fake_add(std::vector<uintptr_t> {0xfa, 0xeb, 0xdc});
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(200));
+  ASSERT_TRUE(pointer != nullptr);
+  memset(pointer, 0, 200);
+  debug_free(pointer);
+
+  pointer[101] = 0xab;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+
+  debug_finalize();
+  initialized = false;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string expected_log(DIVIDER);
+  expected_log += android::base::StringPrintf("6 malloc_debug +++ ALLOCATION %p USED AFTER FREE\n", pointer);
+  expected_log += "6 malloc_debug   pointer[101] = 0xab (expected 0xef)\n";
+  expected_log += "6 malloc_debug Backtrace at time of free:\n";
+  expected_log += "6 malloc_debug   #00 pc 0xfa\n";
+  expected_log += "6 malloc_debug   #01 pc 0xeb\n";
+  expected_log += "6 malloc_debug   #02 pc 0xdc\n";
+  expected_log += DIVIDER;
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, get_malloc_leak_info_invalid) {
+  Init("fill");
+
+  uint8_t* info;
+  size_t overall_size;
+  size_t info_size;
+  size_t total_memory;
+  size_t backtrace_size;
+
+  std::string expected_log("6 malloc_debug get_malloc_leak_info: At least one invalid parameter.\n");
+
+  debug_get_malloc_leak_info(nullptr, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+
+  resetLogs();
+  debug_get_malloc_leak_info(&info, nullptr, &info_size, &total_memory, &backtrace_size);
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+
+  resetLogs();
+  debug_get_malloc_leak_info(&info, &overall_size, nullptr, &total_memory, &backtrace_size);
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+
+  resetLogs();
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, nullptr, &backtrace_size);
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+
+  resetLogs();
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, nullptr);
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, get_malloc_leak_info_not_enabled) {
+  Init("fill");
+
+  uint8_t* info;
+  size_t overall_size;
+  size_t info_size;
+  size_t total_memory;
+  size_t backtrace_size;
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  std::string expected_log(
+      "6 malloc_debug get_malloc_leak_info: Allocations not being tracked, to enable "
+      "set the option 'backtrace'.\n");
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+struct InfoEntry {
+  size_t size;
+  size_t num_frames;
+  uintptr_t frames[0];
+} __attribute__((packed));
+
+TEST_F(MallocDebugTest, get_malloc_leak_info_empty) {
+  Init("backtrace");
+
+  uint8_t* info;
+  size_t overall_size;
+  size_t info_size;
+  size_t total_memory;
+  size_t backtrace_size;
+
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_TRUE(info == nullptr);
+  ASSERT_EQ(0U, overall_size);
+  ASSERT_EQ(0U, info_size);
+  ASSERT_EQ(0U, total_memory);
+  ASSERT_EQ(0U, backtrace_size);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, get_malloc_leak_info_single) {
+  Init("backtrace");
+
+  // Create the expected info buffer.
+  size_t individual_size = 2 * sizeof(size_t) + 16 * sizeof(uintptr_t);
+  std::vector<uint8_t> expected_info(individual_size);
+  memset(expected_info.data(), 0, individual_size);
+
+  InfoEntry* entry = reinterpret_cast<InfoEntry*>(expected_info.data());
+  entry->size = 200;
+  entry->num_frames = 3;
+  entry->frames[0] = 0xf;
+  entry->frames[1] = 0xe;
+  entry->frames[2] = 0xd;
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xf, 0xe, 0xd});
+
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(entry->size));
+  ASSERT_TRUE(pointer != nullptr);
+  memset(pointer, 0, entry->size);
+
+  uint8_t* info;
+  size_t overall_size;
+  size_t info_size;
+  size_t total_memory;
+  size_t backtrace_size;
+
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_TRUE(info != nullptr);
+  ASSERT_EQ(individual_size, overall_size);
+  ASSERT_EQ(individual_size, info_size);
+  ASSERT_EQ(200U, total_memory);
+  ASSERT_EQ(16U, backtrace_size);
+  ASSERT_TRUE(memcmp(expected_info.data(), info, overall_size) == 0);
+
+  debug_free_malloc_leak_info(info);
+
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, get_malloc_leak_info_multi) {
+  Init("backtrace=16");
+
+  // Create the expected info buffer.
+  size_t individual_size = 2 * sizeof(size_t) + 16 * sizeof(uintptr_t);
+  std::vector<uint8_t> expected_info(individual_size * 3);
+  memset(expected_info.data(), 0, individual_size * 3);
+
+  InfoEntry* entry0 = reinterpret_cast<InfoEntry*>(expected_info.data());
+  InfoEntry* entry1 = reinterpret_cast<InfoEntry*>(
+      reinterpret_cast<uintptr_t>(entry0) + individual_size);
+  InfoEntry* entry2 = reinterpret_cast<InfoEntry*>(
+      reinterpret_cast<uintptr_t>(entry1) + individual_size);
+
+  // These values will be in the reverse order that we create.
+  entry2->size = 500;
+  entry2->num_frames = 4;
+  entry2->frames[0] = 0xf;
+  entry2->frames[1] = 0xe;
+  entry2->frames[2] = 0xd;
+  entry2->frames[3] = 0xc;
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xf, 0xe, 0xd, 0xc});
+
+  uint8_t* pointers[3];
+
+  pointers[0] = reinterpret_cast<uint8_t*>(debug_malloc(entry2->size));
+  ASSERT_TRUE(pointers[0] != nullptr);
+  memset(pointers[0], 0, entry2->size);
+
+  entry1->size = 4100;
+  entry1->num_frames = 16;
+  for (size_t i = 0; i < 16; i++) {
+    entry1->frames[i] = 0xbc000 + i;
+  }
+
+  backtrace_fake_add(
+      std::vector<uintptr_t> {0xbc000, 0xbc001, 0xbc002, 0xbc003, 0xbc004, 0xbc005,
+                              0xbc006, 0xbc007, 0xbc008, 0xbc009, 0xbc00a, 0xbc00b,
+                              0xbc00c, 0xbc00d, 0xbc00e, 0xbc00f, 0xffff});
+
+  pointers[1] = reinterpret_cast<uint8_t*>(debug_malloc(entry1->size));
+  ASSERT_TRUE(pointers[1] != nullptr);
+  memset(pointers[1], 0, entry1->size);
+
+  entry0->size = 9000;
+  entry0->num_frames = 1;
+
+  entry0->frames[0] = 0x104;
+  backtrace_fake_add(std::vector<uintptr_t> {0x104});
+
+  pointers[2] = reinterpret_cast<uint8_t*>(debug_malloc(entry0->size));
+  ASSERT_TRUE(pointers[2] != nullptr);
+  memset(pointers[2], 0, entry0->size);
+
+  uint8_t* info;
+  size_t overall_size;
+  size_t info_size;
+  size_t total_memory;
+  size_t backtrace_size;
+
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_TRUE(info != nullptr);
+  ASSERT_EQ(individual_size * 3, overall_size);
+  ASSERT_EQ(individual_size, info_size);
+  ASSERT_EQ(500U + 4100U + 9000U, total_memory);
+  ASSERT_EQ(16U, backtrace_size);
+  ASSERT_TRUE(memcmp(expected_info.data(), info, overall_size) == 0);
+
+  debug_free_malloc_leak_info(info);
+
+  debug_free(pointers[0]);
+  debug_free(pointers[1]);
+  debug_free(pointers[2]);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, get_malloc_leak_info_multi_skip_empty_backtrace) {
+  Init("backtrace=16");
+
+  // Create the expected info buffer.
+  size_t individual_size = 2 * sizeof(size_t) + 16 * sizeof(uintptr_t);
+  std::vector<uint8_t> expected_info(individual_size * 2);
+  memset(expected_info.data(), 0, individual_size * 2);
+
+  InfoEntry* entry0 = reinterpret_cast<InfoEntry*>(expected_info.data());
+  InfoEntry* entry1 = reinterpret_cast<InfoEntry*>(
+      reinterpret_cast<uintptr_t>(entry0) + individual_size);
+
+  // These values will be in the reverse order that we create.
+  entry1->size = 500;
+  entry1->num_frames = 4;
+  entry1->frames[0] = 0xf;
+  entry1->frames[1] = 0xe;
+  entry1->frames[2] = 0xd;
+  entry1->frames[3] = 0xc;
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xf, 0xe, 0xd, 0xc});
+
+  uint8_t* pointers[3];
+
+  pointers[0] = reinterpret_cast<uint8_t*>(debug_malloc(entry1->size));
+  ASSERT_TRUE(pointers[0] != nullptr);
+  memset(pointers[0], 0, entry1->size);
+
+  entry0->size = 4100;
+  entry0->num_frames = 16;
+  for (size_t i = 0; i < 16; i++) {
+    entry0->frames[i] = 0xbc000 + i;
+  }
+
+  backtrace_fake_add(
+      std::vector<uintptr_t> {0xbc000, 0xbc001, 0xbc002, 0xbc003, 0xbc004, 0xbc005,
+                              0xbc006, 0xbc007, 0xbc008, 0xbc009, 0xbc00a, 0xbc00b,
+                              0xbc00c, 0xbc00d, 0xbc00e, 0xbc00f, 0xffff});
+
+  pointers[1] = reinterpret_cast<uint8_t*>(debug_malloc(entry0->size));
+  ASSERT_TRUE(pointers[1] != nullptr);
+  memset(pointers[1], 0, entry0->size);
+
+  pointers[2] = reinterpret_cast<uint8_t*>(debug_malloc(10000));
+  ASSERT_TRUE(pointers[2] != nullptr);
+  memset(pointers[2], 0, 10000);
+
+  uint8_t* info;
+  size_t overall_size;
+  size_t info_size;
+  size_t total_memory;
+  size_t backtrace_size;
+
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_TRUE(info != nullptr);
+  ASSERT_EQ(individual_size * 2, overall_size);
+  ASSERT_EQ(individual_size, info_size);
+  ASSERT_EQ(500U + 4100U, total_memory);
+  ASSERT_EQ(16U, backtrace_size);
+  ASSERT_TRUE(memcmp(expected_info.data(), info, overall_size) == 0);
+
+  debug_free_malloc_leak_info(info);
+
+  debug_free(pointers[0]);
+  debug_free(pointers[1]);
+  debug_free(pointers[2]);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, realloc_usable_size) {
+  Init("front_guard");
+
+  // Verify that if the usable size > size of alloc, that realloc
+  // copies the bytes in the usable size not just the size.
+  // This assumes that an allocation of size 1 returns usable size > 1.
+  // If this isn't true, this test is not going to do anything.
+  uint8_t* pointer = reinterpret_cast<uint8_t*>(debug_malloc(1));
+  ASSERT_TRUE(pointer != nullptr);
+  size_t usable_size = debug_malloc_usable_size(pointer);
+  memset(pointer, 0xaa, usable_size);
+  pointer = reinterpret_cast<uint8_t*>(debug_realloc(pointer, usable_size + 10));
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_LE(usable_size + 10, debug_malloc_usable_size(pointer));
+  for (size_t i = 0; i < usable_size; i++) {
+    ASSERT_EQ(0xaa, pointer[i]) << "Failed compare at byte " << i;
+  }
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, backtrace_enable_on_signal) {
+  Init("backtrace_enable_on_signal=20");
+
+  size_t individual_size = 2 * sizeof(size_t) + 20 * sizeof(uintptr_t);
+
+  backtrace_fake_add(std::vector<uintptr_t> {0xbc000, 0xecd00, 0x12000});
+  backtrace_fake_add(std::vector<uintptr_t> {0x100, 0x200, 0x300, 0x400});
+  backtrace_fake_add(std::vector<uintptr_t> {0x500, 0xa00, 0xb00});
+
+  // First allocation should not actually attempt to get the backtrace.
+  void* pointer = debug_malloc(10);
+  ASSERT_TRUE(pointer != nullptr);
+
+  uint8_t* info;
+  size_t overall_size;
+  size_t info_size;
+  size_t total_memory;
+  size_t backtrace_size;
+
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_TRUE(info == nullptr);
+  ASSERT_EQ(0U, overall_size);
+  ASSERT_EQ(0U, info_size);
+  ASSERT_EQ(0U, total_memory);
+  ASSERT_EQ(0U, backtrace_size);
+  debug_free(pointer);
+
+  debug_free_malloc_leak_info(info);
+
+  // Send the signal to enable.
+  ASSERT_TRUE(kill(getpid(), SIGRTMIN + 10) == 0);
+  sleep(1);
+
+  pointer = debug_malloc(100);
+  ASSERT_TRUE(pointer != nullptr);
+
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_TRUE(info != nullptr);
+  ASSERT_EQ(individual_size, overall_size);
+  ASSERT_EQ(individual_size, info_size);
+  ASSERT_EQ(100U, total_memory);
+  ASSERT_EQ(20U, backtrace_size);
+  uintptr_t* ips = reinterpret_cast<uintptr_t*>(&info[2 * sizeof(size_t)]);
+  ASSERT_EQ(0xbc000U, ips[0]);
+  ASSERT_EQ(0xecd00U, ips[1]);
+  ASSERT_EQ(0x12000U, ips[2]);
+  for (size_t i = 3; i < 20; i++) {
+    ASSERT_EQ(0U, ips[i]);
+  }
+
+  debug_free(pointer);
+
+  debug_free_malloc_leak_info(info);
+
+  // Send the signal to disable.
+  ASSERT_TRUE(kill(getpid(), SIGRTMIN + 10) == 0);
+  sleep(1);
+
+  pointer = debug_malloc(200);
+  ASSERT_TRUE(pointer != nullptr);
+
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_TRUE(info == nullptr);
+  ASSERT_EQ(0U, overall_size);
+  ASSERT_EQ(0U, info_size);
+  ASSERT_EQ(0U, total_memory);
+  ASSERT_EQ(0U, backtrace_size);
+
+  debug_free(pointer);
+
+  debug_free_malloc_leak_info(info);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  std::string expected_log = android::base::StringPrintf(
+      "4 malloc_debug malloc_testing: Run: 'kill -%d %d' to enable backtracing.\n",
+      SIGRTMIN + 10, getpid());
+  ASSERT_STREQ(expected_log.c_str(), getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, overflow) {
+  Init("guard fill_on_free");
+
+  void* pointer = debug_malloc(SIZE_MAX);
+  ASSERT_TRUE(pointer == nullptr);
+  ASSERT_EQ(ENOMEM, errno);
+
+  pointer = debug_calloc(1, SIZE_MAX);
+  ASSERT_TRUE(pointer == nullptr);
+  ASSERT_EQ(ENOMEM, errno);
+
+  pointer = debug_calloc(SIZE_MAX, 1);
+  ASSERT_TRUE(pointer == nullptr);
+  ASSERT_EQ(ENOMEM, errno);
+
+  pointer = debug_calloc(SIZE_MAX/100, 100);
+  ASSERT_TRUE(pointer == nullptr);
+  ASSERT_EQ(ENOMEM, errno);
+
+  pointer = debug_calloc(100, SIZE_MAX/100);
+  ASSERT_TRUE(pointer == nullptr);
+  ASSERT_EQ(ENOMEM, errno);
+
+  pointer = debug_realloc(nullptr, SIZE_MAX);
+  ASSERT_TRUE(pointer == nullptr);
+  ASSERT_EQ(ENOMEM, errno);
+
+  pointer = debug_malloc(100);
+  ASSERT_TRUE(pointer != nullptr);
+  memset(pointer, 0xd0, 100);
+
+  void* realloc_pointer = debug_realloc(pointer, SIZE_MAX);
+  ASSERT_TRUE(realloc_pointer == nullptr);
+  // Verify the pointer was not freed.
+  for (size_t i = 0; i < 100; i++) {
+    ASSERT_EQ(0xd0, reinterpret_cast<uint8_t*>(pointer)[i]) << "Failed checking byte " << i;
+  }
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+static void VerifyZygoteSet(size_t memory_bytes) {
+  size_t expected_info_size = 2 * sizeof(size_t) + 16 * sizeof(uintptr_t);
+  std::vector<uint8_t> expected_info(expected_info_size);
+  memset(expected_info.data(), 0, expected_info_size);
+  InfoEntry* entry = reinterpret_cast<InfoEntry*>(expected_info.data());
+  entry->size = memory_bytes | (1U << 31);
+  entry->num_frames = 1;
+  entry->frames[0] = 0x1;
+
+  uint8_t* info;
+  size_t overall_size;
+  size_t info_size;
+  size_t total_memory;
+  size_t backtrace_size;
+
+  debug_get_malloc_leak_info(&info, &overall_size, &info_size, &total_memory, &backtrace_size);
+  ASSERT_EQ(expected_info_size, overall_size);
+  ASSERT_EQ(expected_info_size, info_size);
+  ASSERT_EQ(memory_bytes, total_memory);
+  ASSERT_EQ(16U, backtrace_size);
+  ASSERT_TRUE(memcmp(info, expected_info.data(), expected_info_size) == 0);
+
+  debug_free_malloc_leak_info(info);
+}
+
+TEST_F(MallocDebugTest, zygote_set) {
+  // Set all of the options.
+  Init("guard fill backtrace leak_track free_track=2");
+
+  zygote = 1;
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x1});
+
+  void* pointer = debug_malloc(100);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(100U, debug_malloc_usable_size(pointer));
+  memset(pointer, 0, 100);
+  VerifyZygoteSet(100);
+  debug_free(pointer);
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x1});
+  pointer = debug_calloc(10, 20);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(200U, debug_malloc_usable_size(pointer));
+  VerifyZygoteSet(200);
+  debug_free(pointer);
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x1});
+  pointer = debug_memalign(128, 300);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(300U, debug_malloc_usable_size(pointer));
+  memset(pointer, 0, 300);
+  VerifyZygoteSet(300);
+  debug_free(pointer);
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x1});
+  pointer = debug_malloc(500);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(500U, debug_malloc_usable_size(pointer));
+  memset(pointer, 0, 500);
+  VerifyZygoteSet(500);
+
+  backtrace_fake_add(std::vector<uintptr_t> {0x1});
+  pointer = debug_realloc(pointer, 300);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(300U, debug_malloc_usable_size(pointer));
+  VerifyZygoteSet(300);
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, max_size) {
+  Init("guard");
+
+  void* pointer = debug_malloc(1U << 31);
+  ASSERT_TRUE(pointer == nullptr);
+
+  pointer = debug_calloc(1, 1U << 31);
+  ASSERT_TRUE(pointer == nullptr);
+
+  pointer = debug_calloc(1U << 31, 1);
+  ASSERT_TRUE(pointer == nullptr);
+
+  pointer = debug_memalign(16, 1U << 31);
+  ASSERT_TRUE(pointer == nullptr);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, debug_mallinfo) {
+  Init("guard");
+
+  void* pointer = debug_malloc(150);
+  ASSERT_TRUE(pointer != nullptr);
+
+  struct mallinfo mi = debug_mallinfo();
+  EXPECT_NE(0U, mi.uordblks);
+
+  debug_free(pointer);
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+TEST_F(MallocDebugTest, debug_posix_memalign) {
+  Init("guard");
+
+  void* pointer;
+  ASSERT_EQ(0, debug_posix_memalign(&pointer, 32, 300));
+  ASSERT_TRUE(pointer != nullptr);
+  debug_free(pointer);
+
+  ASSERT_EQ(EINVAL, debug_posix_memalign(&pointer, 11, 300));
+
+  ASSERT_EQ(ENOMEM, debug_posix_memalign(&pointer, 16, SIZE_MAX));
+
+  ASSERT_STREQ("", getFakeLogBuf().c_str());
+  ASSERT_STREQ("", getFakeLogPrint().c_str());
+}
+
+#if defined(HAVE_DEPRECATED_MALLOC_FUNCS)
+TEST_F(MallocDebugTest, debug_pvalloc) {
+  Init("guard");
+
+  size_t pagesize = getpagesize();
+  void* pointer = debug_pvalloc(1);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(pagesize, debug_malloc_usable_size(pointer));
+  uintptr_t value = reinterpret_cast<uintptr_t>(pointer) & (pagesize - 1);
+  ASSERT_EQ(0U, value);
+  debug_free(pointer);
+}
+
+TEST_F(MallocDebugTest, debug_valloc) {
+  Init("guard");
+
+  size_t pagesize = getpagesize();
+  void* pointer = debug_valloc(100);
+  ASSERT_TRUE(pointer != nullptr);
+  ASSERT_EQ(100U, debug_malloc_usable_size(pointer));
+  uintptr_t value = reinterpret_cast<uintptr_t>(pointer) & (pagesize - 1);
+  ASSERT_EQ(0U, value);
+  debug_free(pointer);
+}
+#endif
diff --git a/libc/malloc_debug/tests/property_fake.cpp b/libc/malloc_debug/tests/property_fake.cpp
new file mode 100644
index 0000000..d9f0ad8
--- /dev/null
+++ b/libc/malloc_debug/tests/property_fake.cpp
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <string.h>
+
+#include <string>
+#include <unordered_map>
+
+#include <sys/system_properties.h>
+
+std::unordered_map<std::string, std::string> g_properties;
+
+extern "C" int property_set(const char* name, const char* value) {
+  if (g_properties.count(name) != 0) {
+    g_properties.erase(name);
+  }
+  g_properties[name] = value;
+  return 0;
+}
+
+extern "C" int property_get(const char* key, char* value, const char* default_value) {
+  if (g_properties.count(key) == 0) {
+    if (default_value == nullptr) {
+      return 0;
+    }
+    strncpy(value, default_value, PROP_VALUE_MAX-1);
+  } else {
+    strncpy(value, g_properties[key].c_str(), PROP_VALUE_MAX-1);
+  }
+  value[PROP_VALUE_MAX-1] = '\0';
+  return strlen(value);
+}
+
+extern "C" int __system_property_get(const char* key, char* value) {
+  if (g_properties.count(key) == 0) {
+    return 0;
+  } else {
+    strncpy(value, g_properties[key].c_str(), PROP_VALUE_MAX-1);
+  }
+  value[PROP_VALUE_MAX-1] = '\0';
+  return strlen(value);
+}